1
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Gray V, Toolan DTW, Dowland S, Allardice JR, Weir MP, Zhang Z, Xiao J, Klimash A, Winkel JF, Holland EK, Fregoso GM, Anthony JE, Bronstein H, Friend R, Ryan AJ, Jones RAL, Greenham NC, Rao A. Ligand-Directed Self-Assembly of Organic-Semiconductor/Quantum-Dot Blend Films Enables Efficient Triplet Exciton-Photon Conversion. J Am Chem Soc 2024; 146:7763-7770. [PMID: 38456418 PMCID: PMC10958494 DOI: 10.1021/jacs.4c00125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 03/09/2024]
Abstract
Blends comprising organic semiconductors and inorganic quantum dots (QDs) are relevant for many optoelectronic applications and devices. However, the individual components in organic-QD blends have a strong tendency to aggregate and phase-separate during film processing, compromising both their structural and electronic properties. Here, we demonstrate a QD surface engineering approach using electronically active, highly soluble semiconductor ligands that are matched to the organic semiconductor host material to achieve well-dispersed inorganic-organic blend films, as characterized by X-ray and neutron scattering, and electron microscopies. This approach preserves the electronic properties of the organic and QD phases and also creates an optimized interface between them. We exemplify this in two emerging applications, singlet-fission-based photon multiplication (SF-PM) and triplet-triplet annihilation-based photon upconversion (TTA-UC). Steady-state and time-resolved optical spectroscopy shows that triplet excitons can be transferred with near unity efficiently across the organic-inorganic interface, while the organic films maintain efficient SF (190% yield) in the organic phase. By changing the relative energy between organic and inorganic components, yellow upconverted emission is observed upon 790 nm NIR excitation. Overall, we provide a highly versatile approach to overcome longstanding challenges in the blending of organic semiconductors with QDs that have relevance for many optical and optoelectronic applications.
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Affiliation(s)
- Victor Gray
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K.
- Department
of Chemistry, Ångström Laboratory, Uppsala University, Box 532, SE-751 20 Uppsala, Sweden
| | - Daniel T. W. Toolan
- Department
of Chemistry, The University of Sheffield, Sheffield S3 7HF, U.K.
- Department
of Materials, The University of Manchester, Engineering Building A, Booth Street
East, Manchester M13 9PL, U.K.
| | - Simon Dowland
- Cambridge
Photon Technology, J.
J. Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Jesse R. Allardice
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Michael P. Weir
- School of
Physics and Astronomy, The University of
Nottingham, University Park, Nottingham NG7 2RD, U.K.
| | - Zhilong Zhang
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - James Xiao
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Anastasia Klimash
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield
Road, Cambridge CB2 1EW, U.K.
| | - Jurjen F. Winkel
- Cambridge
Photon Technology, J.
J. Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Emma K. Holland
- Center
for Applied Energy Research, University
of Kentucky, Research Park Drive, Lexington, Kentucky 40511, United States
| | - Garrett M. Fregoso
- Center
for Applied Energy Research, University
of Kentucky, Research Park Drive, Lexington, Kentucky 40511, United States
| | - John E. Anthony
- Center
for Applied Energy Research, University
of Kentucky, Research Park Drive, Lexington, Kentucky 40511, United States
| | - Hugo Bronstein
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield
Road, Cambridge CB2 1EW, U.K.
| | - Richard Friend
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Anthony J. Ryan
- Department
of Chemistry, The University of Sheffield, Sheffield S3 7HF, U.K.
| | - Richard A. L. Jones
- John
Owens Building, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
| | - Neil C. Greenham
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Akshay Rao
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K.
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2
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Purdy M, Budden P, Fallon K, Gannett CN, Abruña HD, Zeng W, Friend R, Musser AJ, Bronstein H. Re-Thinking Dimer Design Principles with Indolonaphthyridine Intramolecular Singlet Fission. Chemistry 2023; 29:e202301547. [PMID: 37377132 DOI: 10.1002/chem.202301547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/27/2023] [Accepted: 06/27/2023] [Indexed: 06/29/2023]
Abstract
Singlet fission is a phenomenon that could significantly improve the efficiency of photovoltaic devices. Indolonaphthyridine thiophene (INDT) is a photostable singlet fission material that could potentially be utilised in singlet fission-based photovoltaic devices. This study investigates the intramolecular singlet fission (i-SF) mechanism of INDT dimers linked via para-phenyl, meta-phenyl and fluorene bridging groups. Using ultra-fast spectroscopy the highest rate of singlet fission is found in the para-phenyl linked dimer. Quantum calculations show the para-phenyl linker encourages enhanced monomer electronic coupling. Increased rates of singlet fission were also observed in the higher polarity o-dichlorobenzene, relative to toluene, indicating that charge-transfer states have a role in mediating the process. The mechanistic picture of polarisable singlet fission materials, such as INDT, extends beyond the traditional mechanistic landscape.
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Affiliation(s)
- Michael Purdy
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Peter Budden
- Department of Physics, University of Cambridge, Cavendish Laboratory, Cambridge, CB3 0HE, UK
| | - Kealan Fallon
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Cara N Gannett
- Department of Chemistry & Chemical Biology, Cornell University, Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Héctor D Abruña
- Department of Chemistry & Chemical Biology, Cornell University, Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Weixuan Zeng
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Richard Friend
- Department of Physics, University of Cambridge, Cavendish Laboratory, Cambridge, CB3 0HE, UK
| | - Andrew J Musser
- Department of Chemistry & Chemical Biology, Cornell University, Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Hugo Bronstein
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
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3
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Purdy M, Walton JR, Fallon KJ, Toolan DTW, Budden P, Zeng W, Corpinot MK, Bučar DK, van Turnhout L, Friend R, Rao A, Bronstein H. Aza-Cibalackrot: Turning on Singlet Fission Through Crystal Engineering. J Am Chem Soc 2023; 145:10712-10720. [PMID: 37133417 DOI: 10.1021/jacs.3c00971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Singlet fission is a photophysical process that provides a pathway for more efficient harvesting of solar energy in photovoltaic devices. The design of singlet fission candidates is non-trivial and requires careful optimization of two key criteria: (1) correct energetic alignment and (2) appropriate intermolecular coupling. Meanwhile, this optimization must not come at the cost of molecular stability or feasibility for device applications. Cibalackrot is a historic and stable organic dye which, although it has been suggested to have ideal energetics, does not undergo singlet fission due to large interchromophore distances, as suggested by single crystal analysis. Thus, while the energetic alignment is satisfactory, the molecule does not have the desired intermolecular coupling. Herein, we improve this characteristic through molecular engineering with the first synthesis of an aza-cibalackrot and show, using ultrafast transient spectroscopy, that singlet fission is successfully "turned on."
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Affiliation(s)
- Michael Purdy
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Rd, Cambridge CB2 1EW, U.K
| | - Jessica R Walton
- Department of Physics, Cavendish Laboratory, JJ Thomson Avenue, Cambridge CB3 0HE, U.K
| | - Kealan J Fallon
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Rd, Cambridge CB2 1EW, U.K
| | - Daniel T W Toolan
- Department of Chemistry, University of Sheffield, Dainton Building, Brook Hill, Sheffield S3 7HF, U.K
| | - Peter Budden
- Department of Physics, Cavendish Laboratory, JJ Thomson Avenue, Cambridge CB3 0HE, U.K
| | - Weixuan Zeng
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Rd, Cambridge CB2 1EW, U.K
| | - Merina K Corpinot
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
| | - Dejan-Krešimir Bučar
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
| | - Lars van Turnhout
- Department of Physics, Cavendish Laboratory, JJ Thomson Avenue, Cambridge CB3 0HE, U.K
| | - Richard Friend
- Department of Physics, Cavendish Laboratory, JJ Thomson Avenue, Cambridge CB3 0HE, U.K
| | - Akshay Rao
- Department of Physics, Cavendish Laboratory, JJ Thomson Avenue, Cambridge CB3 0HE, U.K
| | - Hugo Bronstein
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Rd, Cambridge CB2 1EW, U.K
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4
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Ganugula R, Nuthalapati NK, Dwivedi S, Zou D, Arora M, Friend R, Sheikh-Hamad D, Basu R, Kumar MNVR. Nanocurcumin combined with insulin alleviates diabetic kidney disease through P38/P53 signaling axis. J Control Release 2023; 353:621-633. [PMID: 36503070 PMCID: PMC9904426 DOI: 10.1016/j.jconrel.2022.12.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 11/30/2022] [Accepted: 12/05/2022] [Indexed: 12/15/2022]
Abstract
Treatments for diabetic kidney disease (DKD) mainly focus on managing hyperglycemia and hypertension, but emerging evidence suggests that inflammation also plays a role in the pathogenesis of DKD. This 10-week study evaluated the efficacy of daily oral nanoparticulate-curcumin (nCUR) together with long-acting insulin (INS) to treat DKD in a rodent model. Diabetic rats were dosed with unformulated CUR alone, nCUR alone or together with INS, or INS alone. The progression of diabetes was reflected by increases in plasma fructosamine, blood urea nitrogen, creatinine, bilirubin, ALP, and decrease in albumin and globulins. These aberrancies were remedied by nCUR+INS or INS but not by CUR or nCUR. Kidney histopathological results revealed additional abnormalities characteristic of DKD, such as basement membrane thickening, tubular atrophy, and podocyte cytoskeletal impairment. nCUR and nCUR+INS mitigated these lesions, while CUR and INS alone were far less effective, if not ineffective. To elucidate how our treatments modulated inflammatory signaling in the liver and kidney, we identified hyperactivation of P38 (MAPK) and P53 with INS and CUR, whereas nCUR and nCUR+INS deactivated both targets. Similarly, the latter interventions led to significant downregulation of renal NLRP3, IL-1β, NF-ĸB, Casp3, and MAPK8 mRNA, indicating a normalization of inflammasome and apoptotic pathways. Thus, we show therapies that reduce both hyperglycemia and inflammation may offer better management of diabetes and its complications.
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Affiliation(s)
- Raghu Ganugula
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, AL, USA; College of Community Health Sciences, The University of Alabama, Tuscaloosa, AL, USA; Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA; Alabama Life Research Institute, The University of Alabama, Tuscaloosa, AL, USA
| | - Nikhil K Nuthalapati
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, AL, USA; College of Community Health Sciences, The University of Alabama, Tuscaloosa, AL, USA
| | - Subhash Dwivedi
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, AL, USA; College of Community Health Sciences, The University of Alabama, Tuscaloosa, AL, USA
| | - Dianxiong Zou
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, AL, USA; College of Community Health Sciences, The University of Alabama, Tuscaloosa, AL, USA
| | - Meenakshi Arora
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, AL, USA; College of Community Health Sciences, The University of Alabama, Tuscaloosa, AL, USA; Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA; Alabama Life Research Institute, The University of Alabama, Tuscaloosa, AL, USA
| | - Richard Friend
- College of Community Health Sciences, The University of Alabama, Tuscaloosa, AL, USA
| | - David Sheikh-Hamad
- Division of Nephrology and Selzman Institute for Kidney Health, Department of Medicine, Baylor College of Medicine, Houston, TX, USA; Center for Translational Research on Inflammatory Diseases, Michael E. Debakey Veterans Affairs Medical Center, Houston, TX, USA
| | - Rita Basu
- Division of Endocrinology, Center of Diabetes Technology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - M N V Ravi Kumar
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, AL, USA; College of Community Health Sciences, The University of Alabama, Tuscaloosa, AL, USA; Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA; Alabama Life Research Institute, The University of Alabama, Tuscaloosa, AL, USA; Department of Pharmaceutical Sciences, Irma Lerma Rangel College of Pharmacy, Texas A&M University, College Station, TX, USA; Chemical and Biological Engineering, University of Alabama, Tuscaloosa, AL, USA; Nephrology Research and Training Center, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA; Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA.
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5
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Fallon K, Sawhney N, Toolan DTW, Sharma A, Zeng W, Montanaro S, Leventis A, Dowland S, Millington O, Congrave D, Bond A, Friend R, Rao A, Bronstein H. Quantitative Singlet Fission in Solution-Processable Dithienohexatrienes. J Am Chem Soc 2022; 144:23516-23521. [PMID: 36575926 PMCID: PMC9801381 DOI: 10.1021/jacs.2c10254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Indexed: 12/29/2022]
Abstract
Singlet fission (SF) is a promising strategy to overcome thermalization losses and enhance the efficiency of single junction photovoltaics (PVs). The development of this field has been strongly material-limited, with a paucity of materials able to undergo SF. Rarer still are examples that can produce excitons of sufficient energy to be coupled to silicon PVs (>1.1 eV). Herein, we examine a series of a short-chain polyene, dithienohexatriene (DTH), with tailored material properties and triplet (T1) energy levels greater than 1.1 eV. We find that these highly soluble materials can be easily spin-cast to create thin films of high crystallinity that exhibit ultrafast singlet fission with near perfect triplet yields of up to 192%. We believe that these materials are the first solution-processable singlet fission materials with quantitative triplet formation and energy levels appropriate for use in conjunction with silicon PVs.
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Affiliation(s)
- Kealan
J. Fallon
- Department
of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K.
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, U.K.
| | - Nipun Sawhney
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, U.K.
| | - Daniel T. W. Toolan
- Department
of Chemistry, University of Sheffield, Dainton Building, Brook Hill, Sheffield S3 7HF, U.K.
| | - Ashish Sharma
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, U.K.
| | - Weixuan Zeng
- Department
of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K.
| | | | - Anastasia Leventis
- Department
of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K.
| | - Simon Dowland
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, U.K.
| | - Oliver Millington
- Department
of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K.
| | - Daniel Congrave
- Department
of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K.
| | - Andrew Bond
- Department
of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K.
| | - Richard Friend
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, U.K.
| | - Akshay Rao
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, U.K.
| | - Hugo Bronstein
- Department
of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K.
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, U.K.
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6
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Dwivedi S, Gottipati A, Ganugula R, Arora M, Friend R, Osburne R, Rodrigues-Hoffman A, Basu R, Pan HL, Kumar MNVR. Oral Nanocurcumin Alone or in Combination with Insulin Alleviates STZ-Induced Diabetic Neuropathy in Rats. Mol Pharm 2022; 19:4612-4624. [PMID: 36106748 PMCID: PMC9972482 DOI: 10.1021/acs.molpharmaceut.2c00465] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Diabetes mellitus (DM), a multifaceted metabolic disorder if not managed properly leads to secondary complications. Diabetic peripheral neuropathy (DPN) is one such complication caused by nerve damage that cannot be reversed but can be delayed. Recently, diabetes patients are using dietary supplements, although there remains a general skepticism about this practice. Curcumin (CUR), one such supplement can help prevent underlying low-grade inflammation in diabetes, but it is plagued by poor oral bioavailability. To better understand the role of bioavailability in clinical outcomes, we have tested double-headed nanosystems containing curcumin (nCUR) on DPN. Because CUR does not influence glucose levels, we have also tested the effects of nCUR combined with long-acting subcutaneous insulin (INS). nCUR with or without INS alleviates DPN at two times lower dose than unformulated CUR, as indicated by qualitative and quantitative analysis of the hind paw, sciatic nerve, spleen, and L4-6 spinal cord. In addition, nCUR and nCUR+INS preserve hind paw nerve axons as evident by the Bielschowsky silver stain and intraepidermal nerve fibers (IENF) density measured by immunofluorescence. The mechanistic studies further corroborated the results, where nCUR or nCUR+INS showed a significant decrease in TUNEL positive cells, mRNA expression of NLRP3, IL-1β, and macrophage infiltration while preserving nestin and NF200 expression in the sciatic nerve. Together, the data confirms that CUR bioavailability is proportional to clinical outcomes and INS alone may not be one of the solutions for DM. This study highlights the potential of nCUR with or without INS in alleviating DPN and warrants further investigation.
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Affiliation(s)
- Subhash Dwivedi
- College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- Alabama Life Research Institute, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
| | - Anuhya Gottipati
- College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- Alabama Life Research Institute, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
| | - Raghu Ganugula
- College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- Alabama Life Research Institute, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
| | - Meenakshi Arora
- College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- Alabama Life Research Institute, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
| | - Richard Friend
- College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
| | - Robert Osburne
- College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
| | - Aline Rodrigues-Hoffman
- Department of Comparative, Diagnostic & Population Medicine, College of Veterinary Medicine, University of Florida, 2015 SW 16th Avenue, Gainesville, Florida32611-7011, United States
| | - Rita Basu
- Division of Endocrinology, Center of Diabetes Technology, University of Virginia School of Medicine, Charlottesville, Virginia22908, United States
| | - Hui-Lin Pan
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas77030, United States
| | - M N V Ravi Kumar
- College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- The Center for Convergent Bioscience and Medicine (CCBM), The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- Alabama Life Research Institute, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- Chemical and Biological Engineering, University of Alabama, Tuscaloosa, Alabama35487-0166, United States
- Department of Pharmaceutical Sciences, Irma Lerma Rangel College of Pharmacy, Texas A&M University, College Station, Texas77843, United States
- Nephrology Research and Training Center, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama35401, United States
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, Alabama35401, United States
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7
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Schwarz C, Procaccianti C, Costa L, Brini R, Friend R, Caivano G, Sadafi H, Mussche C, Schwenck N, Hahn M, Murgia X, Bianco F. Differential Performance and Lung Deposition of Levofloxacin with Different Nebulisers Used in Cystic Fibrosis. Int J Mol Sci 2022; 23:ijms23179597. [PMID: 36076992 PMCID: PMC9455972 DOI: 10.3390/ijms23179597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/15/2022] [Accepted: 08/19/2022] [Indexed: 11/16/2022] Open
Abstract
We compared the performance and levofloxacin (Quinsair) lung deposition of three nebulisers commonly used in CF (I-Neb Advance, eFlow rapid, and LC Plus) with the approved nebuliser Zirela. The delivered dose, delivery rate, and aerosol particle size distribution (APSD) for each device were determined using the methods described in the Pharmacopeia. High-resolution computed tomography scans obtained from seven adult patients with mild CF were used to generate computer-aided, three-dimensional models of their airway tree to assess lung deposition using functional respiratory imaging (FRI). The eFlow rapid and the LC Plus showed poor delivery efficiencies due to their high residual volumes. The I-Neb, which only delivers aerosols during the inspiratory phase, achieved the highest aerosol delivery efficiency. However, the I-Neb showed the largest particle size and lowest delivery rate (2.9 mg/min), which were respectively associated with a high extrathoracic deposition and extremely long nebulisation times (>20 min). Zirela showed the best performance considering delivery efficiency (159.6 mg out of a nominal dose of 240 mg), delivery rate (43.5 mg/min), and lung deposition (20% of the nominal dose), requiring less than 5 min to deliver a full dose of levofloxacin. The present study supports the use of drug-specific nebulisers and discourages the off-label use of general-purpose devices with the present levofloxacin formulation since subtherapeutic lung doses and long nebulisation times may compromise treatment efficacy and adherence.
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Affiliation(s)
- Carsten Schwarz
- Division Cystic Fibrosis, CF Center Westbrandenburg, Campus Potsdam, Clinic Westbrandenburg, 14467 Potsdam, Germany
| | | | - Laura Costa
- Global Medical Affairs, Chiesi Farmaceutici S.p.A., 43122 Parma, Italy
| | - Riccardo Brini
- Global Technical Development, Chiesi Ltd., Chippenham SN14 0AB, UK
| | - Richard Friend
- Global Technical Development, Chiesi Ltd., Chippenham SN14 0AB, UK
| | - Grazia Caivano
- Global Technical Development, Chiesi Farmaceutici S.p.A., 43122 Parma, Italy
| | | | | | | | | | | | - Federico Bianco
- Global Medical Affairs, Chiesi Farmaceutici S.p.A., 43122 Parma, Italy
- Correspondence:
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8
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McCourt E, Harper N, Butnoris M, Friend R, Dekker K, Ayre J, Tai B, Pelecanos A, Stowasser D, Coombes I, Dunn T, Donovan P. The effect of Computerised Physician Order Entry on prescribing errors: an interrupted time-series study at a secondary referral hospital in Australia. Int J Med Inform 2022; 165:104829. [DOI: 10.1016/j.ijmedinf.2022.104829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 06/08/2022] [Accepted: 06/30/2022] [Indexed: 10/17/2022]
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9
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Rabbani MMG, Cotton M, Friend R. Climate change and non-migration - exploring the role of place relations in rural and coastal Bangladesh. Popul Environ 2022; 44:99-122. [PMID: 35615058 PMCID: PMC9123852 DOI: 10.1007/s11111-022-00402-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
Of growing research and policy interest are the experiences of people living under conditions of climate change-induced environmental stress, which either are unable to migrate (sometimes described as a 'trapped population') or are seemingly unwilling to do so (sometimes described as the 'voluntarily immobile'). This paper problematises and expands upon these binary categories: examining the complex dimensionality of non-migration as a form of place relations, explored through qualitative study of rural and coastal Bangladeshi communities. Through 60 semi-structured interviews of individuals from four communities in the Kalapara region, the analysis proffers four qualitatively derived and inter-related dimensions of voluntary and involuntary non-migration framed as a form of place relations. These four dimensions concern the following: (1) livelihood opportunities, (2) place obduracy, (3) risk perceptions, and (4) social-structural constraints, with the interplay between these elements explaining diverse non-migratory experiences. In our analysis, 'place obduracy' is introduced as a concept to describe the differential speed of environmental change and socio-cultural adaptation responses to explain non-migratory experiences. Our discussion provides insight into how to best support non-migrant people's adaptive capacity in the face of growing climate emergency.
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Affiliation(s)
| | - Matthew Cotton
- School of Social Sciences, Humanities and Law, Teesside University, Middlesbrough, UK
| | - Richard Friend
- Department of Environment and Geography, University of York, York, UK
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10
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Pandya R, Chen RYS, Gu Q, Gorman J, Auras F, Sung J, Friend R, Kukura P, Schnedermann C, Rao A. Femtosecond Transient Absorption Microscopy of Singlet Exciton Motion in Side-Chain Engineered Perylene-Diimide Thin Films. J Phys Chem A 2020; 124:2721-2730. [PMID: 32130861 PMCID: PMC7132576 DOI: 10.1021/acs.jpca.0c00346] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 03/04/2020] [Indexed: 12/21/2022]
Abstract
We present a statistical analysis of femtosecond transient absorption microscopy applied to four different organic semiconductor thin films based on perylene-diimide (PDI). By achieving a temporal resolution of 12 fs with simultaneous sub-10 nm spatial precision, we directly probe the underlying exciton transport characteristics within 3 ps after photoexcitation free of model assumptions. Our study reveals sub-picosecond coherent exciton transport (12-45 cm2 s-1) followed by a diffusive phase of exciton transport (3-17 cm2 s-1). A comparison between the different films suggests that the exciton transport in the studied materials is intricately linked to their nanoscale morphology, with PDI films that form large crystalline domains exhibiting the largest diffusion coefficients and transport lengths. Our study demonstrates the advantages of directly studying ultrafast transport properties at the nanometer length scale and highlights the need to examine nanoscale morphology when investigating exciton transport in organic as well as inorganic semiconductors.
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Affiliation(s)
- Raj Pandya
- Department
of Physics, Cavendish Laboratory, University
of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Richard Y. S. Chen
- Department
of Physics, Cavendish Laboratory, University
of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Qifei Gu
- Department
of Physics, Cavendish Laboratory, University
of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Jeffrey Gorman
- Department
of Physics, Cavendish Laboratory, University
of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Florian Auras
- Department
of Physics, Cavendish Laboratory, University
of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Jooyoung Sung
- Department
of Physics, Cavendish Laboratory, University
of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Richard Friend
- Department
of Physics, Cavendish Laboratory, University
of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Philipp Kukura
- Physical
and Theoretical Chemistry Laboratory, Oxford
University, South Parks Road, Oxford OX1 3QZ, U.K.
| | - Christoph Schnedermann
- Department
of Physics, Cavendish Laboratory, University
of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K.
| | - Akshay Rao
- Department
of Physics, Cavendish Laboratory, University
of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K.
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11
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Kim VO, Broch K, Belova V, Chen YS, Gerlach A, Schreiber F, Tamura H, Della Valle RG, D'Avino G, Salzmann I, Beljonne D, Rao A, Friend R. Singlet exciton fission via an intermolecular charge transfer state in coevaporated pentacene-perfluoropentacene thin films. J Chem Phys 2019; 151:164706. [PMID: 31675857 DOI: 10.1063/1.5130400] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Singlet exciton fission is a spin-allowed process in organic semiconductors by which one absorbed photon generates two triplet excitons. Theory predicts that singlet fission is mediated by intermolecular charge-transfer states in solid-state materials with appropriate singlet-triplet energy spacing, but direct evidence for the involvement of such states in the process has not been provided yet. Here, we report on the observation of subpicosecond singlet fission in mixed films of pentacene and perfluoropentacene. By combining transient spectroscopy measurements to nonadiabatic quantum-dynamics simulations, we show that direct excitation in the charge-transfer absorption band of the mixed films leads to the formation of triplet excitons, unambiguously proving that they act as intermediate states in the fission process.
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Affiliation(s)
- Vincent O Kim
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Katharina Broch
- Fritz Haber Institute of the Max Planck Society, Department of Physical Chemistry, Faradayweg, 4-614195 Berlin, Germany
| | - Valentina Belova
- Eberhard-Karls Universität Tübingen, Institut für Angewandte Physik, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Y S Chen
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Alexander Gerlach
- Eberhard-Karls Universität Tübingen, Institut für Angewandte Physik, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Frank Schreiber
- Eberhard-Karls Universität Tübingen, Institut für Angewandte Physik, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Hiroyuki Tamura
- Department of Chemical System Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Raffaele Guido Della Valle
- Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna and INSTM-UdR Bologna, Viale Risorgimento 4, 40136 Bologna, Italy
| | - Gabriele D'Avino
- Institut Néel, CNRS and Grenoble Alpes University, F-38042 Grenoble, France
| | - Ingo Salzmann
- Department of Physics, Department of Chemistry and Biochemistry, Centre for Research in Molecular Modeling (CERMM), Centre for NanoScience Research (CeNSR), Concordia University, 7141 Sherbrooke St. West, Montreal, Quebec H4B 1R6, Canada
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, Department of Chemistry, Université de Mons, Place du Parc 20, 7000 Mons, Belgium
| | - Akshay Rao
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Richard Friend
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
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12
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Ahmad S, Sadhanala A, Hoye RLZ, Andrei V, Modarres MH, Zhao B, Rongé J, Friend R, De Volder M. Triple-Cation-Based Perovskite Photocathodes with AZO Protective Layer for Hydrogen Production Applications. ACS Appl Mater Interfaces 2019; 11:23198-23206. [PMID: 31252465 DOI: 10.1021/acsami.9b04963] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Metal halide perovskites are actively pursued as photoelectrodes to drive solar fuel synthesis. However, currently, these photocathodes suffer from limited stability in water, which hampers their practical application. Here, we report a high-performance solution-processable photocathode composed of cesium formamidinium methylammonium triple-cation lead halide perovskite protected by an Al-doped ZnO (AZO) layer combined with a Field's metal encapsulation. Careful selection of charge transport layers resulted in an improvement in photocurrent, fill factor, device stability and reproducibility. The dead pixels count reduced from 25 to 6% for the devices with an AZO layer, and in photocathodes with an AZO layer the photocurrent density increased by almost 20% to 14.3 mA cm-2. In addition, we observed a 5-fold increase in the device lifetime for photocathodes with AZO, which reached up to 18 h before complete failure. Finally, the photocathodes are fabricated using low-cost and scalable methods, which have promise to become compatible with standard solution-based processes.
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Affiliation(s)
- Shahab Ahmad
- Centre for Nanoscience and Nanotechnology , Jamia Millia Islamia (A Central University) , New Delhi 110025 , India
- Institute for Manufacturing, Department of Engineering , University of Cambridge , Cambridge CB3 0FS , United Kingdom
| | - Aditya Sadhanala
- Cavendish Laboratory , University of Cambridge , JJ Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - Robert L Z Hoye
- Cavendish Laboratory , University of Cambridge , JJ Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - Virgil Andrei
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , United Kingdom
| | - Mohammad Hadi Modarres
- Institute for Manufacturing, Department of Engineering , University of Cambridge , Cambridge CB3 0FS , United Kingdom
| | - Baodan Zhao
- Cavendish Laboratory , University of Cambridge , JJ Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - Jan Rongé
- Centre for Surface Chemistry and Catalysis , KU Leuven , Leuven B-3001 , Belgium
| | - Richard Friend
- Cavendish Laboratory , University of Cambridge , JJ Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - Michael De Volder
- Institute for Manufacturing, Department of Engineering , University of Cambridge , Cambridge CB3 0FS , United Kingdom
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13
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Gregg A, Tutek J, Leatherwood MD, Crawford W, Friend R, Crowther M, McKinney R. Systematic Review of Community Paramedicine and EMS Mobile Integrated Health Care Interventions in the United States. Popul Health Manag 2019; 22:213-222. [PMID: 30614761 DOI: 10.1089/pop.2018.0114] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Emergency medical services (EMS) in the United States are frequently used for nonurgent medical needs. Use of 911 and the emergency department (ED) for primary care-treatable conditions is expensive, inefficient, and undesirable for patients and providers. The objective is to describe the outcomes from community paramedicine (CP) and mobile integrated health care (MIH) interventions related to the Quadruple Aim. Three electronic databases were searched for peer-review literature on CP-MIH interventions in the United States. Eight articles reporting data from 7 interventions were included. Four studies reported high levels of patient satisfaction, and only 3 measured health outcomes. No study reported provider satisfaction measures. Reducing ED and inpatient utilization were the most common study outcomes, and programs generally were successful at reducing utilization. With reduced utilization, costs should be reduced; however, most studies did not quantify savings. Future studies should conduct economic analyses that not only compare the intervention to traditional EMS services, but also measure potential cost savings to the EMS agencies running the intervention. Most cost savings from reduced utilization will be to insurance companies and patients, but more efficient use of EMS agencies' resources could lead to cost savings that could offset intervention implementation costs. The other 3 aims (health, patient satisfaction, and provider satisfaction) were reported inconsistently in these studies and need to be addressed further. Given the small number of heterogeneous studies reviewed, the potential for CP-MIH interventions to comprehensively address the Quadruple Aim is still unclear, and more research on these programs is needed.
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Affiliation(s)
- Abbey Gregg
- 1 Institute for Rural Health Research, College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama
| | - Joshua Tutek
- 2 Department of Psychology, College of Arts and Sciences, The University of Alabama, Tuscaloosa, Alabama
| | - Matthew D Leatherwood
- 3 Department of Kinesiology, College of Education, The University of Alabama, Moore Hall, Tuscaloosa, Alabama
| | - William Crawford
- 1 Institute for Rural Health Research, College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama
- 4 Office of EMS, Alabama Department of Public Health, Montgomery, Alabama
| | - Richard Friend
- 5 Department of Family, Internal, and Rural Medicine and College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama
| | - Martha Crowther
- 1 Institute for Rural Health Research, College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama
- 5 Department of Family, Internal, and Rural Medicine and College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama
| | - Robert McKinney
- 6 Department of Psychiatry and Behavioral Health, College of Community Health Sciences, The University of Alabama, Tuscaloosa, Alabama
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14
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Lombeck F, Marx F, Strassel K, Kunz S, Lienert C, Komber H, Friend R, Sommer M. To branch or not to branch: C–H selectivity of thiophene-based donor–acceptor–donor monomers in direct arylation polycondensation exemplified by PCDTBT. Polym Chem 2017. [DOI: 10.1039/c7py00879a] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The possibility for unselective C–H activation of a thiophene-based, donor–acceptor–donor monomer during direct arylation polycondensation is investigated.
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Affiliation(s)
- Florian Lombeck
- Makromolekulare Chemie
- Universität Freiburg
- 79104 Freiburg
- Germany
- Optoelectronics Group
| | - Franziska Marx
- Makromolekulare Chemie
- Universität Freiburg
- 79104 Freiburg
- Germany
| | - Karen Strassel
- Makromolekulare Chemie
- Universität Freiburg
- 79104 Freiburg
- Germany
| | - Susanna Kunz
- Makromolekulare Chemie
- Universität Freiburg
- 79104 Freiburg
- Germany
| | | | - Hartmut Komber
- Leibniz-Institut für Polymerforschung Dresden e.V
- 01069 Dresden
- Germany
| | - Richard Friend
- Optoelectronics Group
- Cavendish Laboratory
- J.J. Thomson Avenue
- University of Cambridge
- Cambridge CB3 0HE
| | - Michael Sommer
- Makromolekulare Chemie
- Universität Freiburg
- 79104 Freiburg
- Germany
- Freiburger Materialforschungszentrum
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15
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Mukhopadhyay T, Puttaraju B, Senanayak SP, Sadhanala A, Friend R, Faber HA, Anthopoulos TD, Salzner U, Meyer A, Patil S. Air-Stable n-channel Diketopyrrolopyrrole-Diketopyrrolopyrrole Oligomers for High Performance Ambipolar Organic Transistors. ACS Appl Mater Interfaces 2016; 8:25415-25427. [PMID: 27592516 DOI: 10.1021/acsami.6b08453] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
n-channel organic semiconductors are prone to oxidation upon exposed to ambient conditions. Herein, we report design and synthesis of diketopyrrolopyrrole (DPP)-based oligomers for ambipolar organic thin-film transistors (OFETs) with excellent air and bias stability at ambient conditions. The cyclic voltammetry measurements reveal exceptional electrochemical stability during the redox cycle of oligomers. Structural properties including aggregation, crystallinity, and morphology in thin film were investigated by UV-visible spectroscopy, atomic force microscopy (AFM), thin-film X-ray diffraction (XRD), and grazing incidence small-angle X-ray scattering (GISAXS) measurements. AFM reveals morphological changes induced by different processing conditions whereas GISAXS measurements show an increase in the population of face-on oriented crystallites in films subjected to a combination of solvent and thermal treatments. These measurements also highlight the significance of chalcogen atom from sulfur to selenium on the photophysical, optical, electronic, and solid-state properties of DPP-DPP oligomers. Charge carrier mobilities of the oligomers were investigated by fabricating top-gate bottom-contact (TG-BC) thin-film transistors by annealing the thin films under various conditions. Combined solvent and thermal annealing of DPP-DPP oligomer thin films results in consistent electron mobilities as high as ∼0.2 cm(2) V(-1) s(-1) with an on/off ratio exceeding 10(4). Field-effect behavior was retained for up to ∼4 weeks, which illustrates remarkable air and bias stability. This work paves the way toward the development of n-channel DPP-DPP-based oligomers exhibiting retention of field-effect behavior with superior stability at ambient conditions.
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Affiliation(s)
- Tushita Mukhopadhyay
- Solid State and Structural Chemistry Unit, Indian Institute of Science , Bangalore 560012, India
| | - Boregowda Puttaraju
- Solid State and Structural Chemistry Unit, Indian Institute of Science , Bangalore 560012, India
| | - Satyaprasad P Senanayak
- Cavendish Laboratory, Department of Physics, University of Cambridge , Cambridge CB3 0HE, United Kingdom
| | - Aditya Sadhanala
- Cavendish Laboratory, Department of Physics, University of Cambridge , Cambridge CB3 0HE, United Kingdom
| | - Richard Friend
- Cavendish Laboratory, Department of Physics, University of Cambridge , Cambridge CB3 0HE, United Kingdom
| | - Hendrik A Faber
- Department of Physics and Centre for Plastic Electronics, Blackett Laboratory, Imperial College London , London 7W72BW, United Kingdom
| | - Thomas D Anthopoulos
- Department of Physics and Centre for Plastic Electronics, Blackett Laboratory, Imperial College London , London 7W72BW, United Kingdom
| | - Ulrike Salzner
- Department of Chemistry, Bilkent University , 06800 Bilkent/Ankara, Turkey
| | - Andreas Meyer
- Institut für Physikalische Chemie, Universität Hamburg , 20148 Hamburg, Germany
| | - Satish Patil
- Solid State and Structural Chemistry Unit, Indian Institute of Science , Bangalore 560012, India
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16
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17
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Underhill AE, Clark RA, Clemenson PI, Friend R, Allen M, Marsden I, Kobayashi A, Kobayashi H. Molecular Conductors Based on Complex Metal Anions. PHOSPHORUS SULFUR 2006. [DOI: 10.1080/10426509208045853] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- A. E. Underhill
- a Department of Chemistry , University of Wales , Bangor , U.K
| | - R. A. Clark
- a Department of Chemistry , University of Wales , Bangor , U.K
| | - P. I. Clemenson
- a Department of Chemistry , University of Wales , Bangor , U.K
| | - R. Friend
- b Cavendish Laboratory, University of Cambridge , Madingley, Road, Cambridge , U.K
| | - M. Allen
- b Cavendish Laboratory, University of Cambridge , Madingley, Road, Cambridge , U.K
| | - I. Marsden
- b Cavendish Laboratory, University of Cambridge , Madingley, Road, Cambridge , U.K
| | - A. Kobayashi
- c Department of Chemistry , Faculty of Science, University of Tokyo , Bunkyo-ku, Tokyo , 113 , Japan
| | - H. Kobayashi
- d Department of Chemistry , Faculty of Science, Toho University , Miyama 2-2-1, Funabashi, Chiba , 274 , Japan
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18
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Yim KH, Friend R, Kim JS. Anisotropic optical properties in electroluminescent conjugated polymers based on grazing angle photoluminescence measurements. J Chem Phys 2006; 124:184706. [PMID: 16709130 DOI: 10.1063/1.2198539] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Grazing angle photoluminescence (GPL) originates from a waveguided light emitted at grazing angle to the substrate due to the total internal reflections, and the light emission is polarized with enhanced intensity at selective mode wavelength. GPL measurements reveal the optical anisotropy of luminescent conjugated polymers, in particular, the alignment of emitting dipoles from which emission occurs, in contrast to spectroscopic ellipsometry measurements that give the anisotropy in the absorption. Based on the GPL emission intensities and spectra, we investigate the anisotropic optical properties in electroluminescent poly(9,9'-di-n-octylfluorene-alt-benzothiadiazole) (F8BT) conjugated polymer thin films of different molecular weights (M(n) = 9-255 kg/mol), both in the pristine and annealed states. The optical anisotropy in F8BT films generally increases with molecular weight, suggesting that higher molecular weight polymers with longer chains are more likely to lie in-plane to the substrate. Upon annealing, high molecular weight F8BT films show even a higher degree of anisotropy, in contrast to low molecular weight F8BT films that become more isotropic. Annealing causes the polymer chains to rearrange and adopt a configuration in which the interchain exciton migration to better ordered low energy (LE) emissive states is strongly suppressed. We observe that the emissive states in F8BT are strongly affected by the local polymer chain arrangement, producing the less ordered high energy (HE) emissive states near the substrate interface where there is a higher degree of chain disorder and the LE states in the bulk of the film. When spin coated onto a quartz substrate precoated with a poly(styrenesulfonate)-doped poly(3,4-ethylenedioxythiophene) (PEDOT:PSS) layer, films of F8BT show severe luminescence quenching near the PEDOT:PSS interface for both the LE and HE emissive states, but a selective quenching of the LE states in the bulk of the film. These observations have important implications for fabricating efficient electronic devices using conjugated polymers as an active material, since the performance of these devices will strongly depend on anisotropic optical properties of electroluminescent conjugated polymers.
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Affiliation(s)
- Keng-Hoong Yim
- Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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20
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Griffin KW, Friend R, Kaell AT, Bennett RS. Distress and disease status among patients with rheumatoid arthritis: roles of coping styles and perceived responses from support providers. Ann Behav Med 2001; 23:133-8. [PMID: 11394555 DOI: 10.1207/s15324796abm2302_8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Previous research has shown that social support can have a beneficial impact on coping processes and psychological adjustment in patients with rheumatoid arthritis (RA). The association of individual coping styles and perceived responses from others to one's pain episodes with patients 'distress and disease status over time was investigated. The sample consisted of 42 middle-aged patients with RA who were predominantly White (98%), female (64%), and married (88%). Participants completed surveys and their rheumatologist completed clinical assessments of patient disease status at 2 time points over a 9-month period. Although punishing responses from others (e.g., getting irritated or angry when the patient is in pain) were perceived as relatively infrequent, they were associated with a patient coping style of focusing on and venting of negative emotion as well as elevated negative affect (NA). Findings also indicated that those who perceived punishing responses from close others and coped by venting negative emotions reported increased NA over time and were rated by their rheumatologist as having more severe RA disease status over time. Implications for psychosocial intervention and directions for future research are discussed.
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Affiliation(s)
- K W Griffin
- Department of Public Health, Weill Medical College of Cornell University, New York, NY 10021, USA.
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21
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Leake R, Friend R, Wadhwa N. Improving adjustment to chronic illness through strategic self-presentation: an experimental study on a renal dialysis unit. Health Psychol 1999. [PMID: 9925046 DOI: 10.1037//0278-6133.18.1.54] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Laboratory studies show that strategic self-presentations strongly influence private self-evaluations. The present study experimentally manipulated self-presentations of dialysis patients' coping skills in order to influence their adjustment. In all, 42 renal dialysis patients matched for diabetes, gender, and dialysis years were randomly assigned to 3 conditions; adjustment was assessed at baseline, post-intervention, and 1 month follow-up. Patients in a self-presentation condition selectively presented themselves as successful copers in a videotaped interview, ostensibly as part of a training program for new patients. Patients in a problem disclosure condition discussed problems with managing their illness. Control group patients viewed a medical videotape about adjusting to dialysis. Patients in the self-presentation condition reported better adjustment, fewer physical symptoms, and more coping skills 1 month later, compared with patients in the other 2 conditions. In addition, coping skills were shown to mediate the relationship between strategic self-presentation and adjustment.
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Affiliation(s)
- R Leake
- Department of Psychology, State University of New York at Stony Brook, 11794-2500, USA
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22
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Leake R, Friend R, Wadhwa N. Improving adjustment to chronic illness through strategic self-presentation: an experimental study on a renal dialysis unit. Health Psychol 1999; 18:54-62. [PMID: 9925046 DOI: 10.1037/0278-6133.18.1.54] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Laboratory studies show that strategic self-presentations strongly influence private self-evaluations. The present study experimentally manipulated self-presentations of dialysis patients' coping skills in order to influence their adjustment. In all, 42 renal dialysis patients matched for diabetes, gender, and dialysis years were randomly assigned to 3 conditions; adjustment was assessed at baseline, post-intervention, and 1 month follow-up. Patients in a self-presentation condition selectively presented themselves as successful copers in a videotaped interview, ostensibly as part of a training program for new patients. Patients in a problem disclosure condition discussed problems with managing their illness. Control group patients viewed a medical videotape about adjusting to dialysis. Patients in the self-presentation condition reported better adjustment, fewer physical symptoms, and more coping skills 1 month later, compared with patients in the other 2 conditions. In addition, coping skills were shown to mediate the relationship between strategic self-presentation and adjustment.
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Affiliation(s)
- R Leake
- Department of Psychology, State University of New York at Stony Brook, 11794-2500, USA
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23
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Friend R, Hatchett L, Schneider MS, Wadhwa NK. A comparison of attributions, health beliefs, and negative emotions as predictors of fluid adherence in renal dialysis patients: a prospective analysis. Ann Behav Med 1998; 19:344-7. [PMID: 9706360 DOI: 10.1007/bf02895152] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Excessive fluid intake in hemodialysis patients can lead to serious cardiovascular complications. However, previous studies have not investigated factors that affect fluid adherence over time. The influence of three sets of factors--attributions, health beliefs, and negative emotions--was examined to determine their influence on changes in fluid adherence over time. We assessed patient's fluid-intake changes across two time periods, as well as their absolute level. The results indicated that attributions, while predicting absolute fluid adherence, did not predict changes in fluid adherence. On the other hand, health beliefs predicted changes in fluid adherence but not absolute levels. Negative emotions predicted neither absolute nor changes in fluid adherence. It is suggested that attributions are more responsible for maintenance and control of stable fluid adherence levels, while health beliefs are more responsible for motivational factors related to changes in fluid adherence over time.
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Affiliation(s)
- R Friend
- Department of Psychology, State University of New York, Stony Brook 11794-2500, USA
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Friend R, Hatchett L, Wadhwa NK, Suh H. Serum albumin and depression in end-stage renal disease. Adv Perit Dial 1997; 13:155-7. [PMID: 9360672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The purpose of our study was to determine whether albumin influenced patients' depression or whether depression influenced patients' albumin. Patients from a tertiary care university medical hospital were assessed for both serum albumin and depression [Beck Depression Inventory (BDI)] at two time points separated by 6 months. Data were collected for 72 patients (43 male, 29 female; mean age 54 years). The sample consisted of 32 hemodialysis and 40 peritoneal dialysis patients. The outcome measures were changes in depression and albumin over time. Regression analysis indicated that all three Time 1 measures of BDI, BDICOG (BDI cognitive), and BDISOM (BDI somatic) significantly predicted decreases in albumin from Time 1 to Time 2 (beta = -0.22, p < 0.002; beta = -0.17, p < 0.015; beta = -0.23, p < 0.002, respectively). However, Time 1 measures of albumin did not predict changes in BDI, BDICOG, or BDISOM (beta = -0.04, p < 0.738; beta = -0.08, p < 0.375; beta = -0.07, p < 0.618, respectively). Thus depression at Time 1 predicted decreases in albumin from Time 1 to Time 2. The reverse effect that albumin influences depression from Time 1 to Time 2 was not found. In conclusion, this study suggests that depression influences the nutritional status indicated by albumin levels. Thus poor nutritional status may mediate the relation between depression and mortality in end-stage renal disease (ESRD).
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Affiliation(s)
- R Friend
- Department of Psychology, State University of New York at Stony Brook, USA
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Abstract
Chronic illness places considerable burdens on patients and their interpersonal relations with families. In this study, patients' perceptions of family and medical staff expectations regarding responsibility for care and routine functions were examined. The authors hypothesized that a patient's perceived inability to meet others' expectations about coping with illness would lead to poorer adjustment. Forty-two chronically ill patients were assessed prospectively for perceptions of others' expectations, social support, and psychological adjustment. Findings confirmed that expectations predicted subsequent decreases in psychological adjustment over a 3-month period, even when social support was controlled. A test of the reverse hypothesis showed that poorly adjusted patients did not misperceive others' expectations. Theoretical interpretations of the findings and their relation to social support research are discussed.
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Affiliation(s)
- L Hatchett
- Department of Psychology, State University of New York at Stony Brook 11794-2500, USA
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Abstract
Chronic illness places considerable burdens on patients and their interpersonal relations with families. In this study, patients' perceptions of family and medical staff expectations regarding responsibility for care and routine functions were examined. The authors hypothesized that a patient's perceived inability to meet others' expectations about coping with illness would lead to poorer adjustment. Forty-two chronically ill patients were assessed prospectively for perceptions of others' expectations, social support, and psychological adjustment. Findings confirmed that expectations predicted subsequent decreases in psychological adjustment over a 3-month period, even when social support was controlled. A test of the reverse hypothesis showed that poorly adjusted patients did not misperceive others' expectations. Theoretical interpretations of the findings and their relation to social support research are discussed.
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Affiliation(s)
- L Hatchett
- Department of Psychology, State University of New York at Stony Brook 11794-2500, USA
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Wadhwa NK, Friend R, Gaus V, Taylor KL, Schneider MS. Weight reduction and fluid intake in an obese and fluid noncompliant ESRD patient. Clin Nephrol 1996; 45:320-4. [PMID: 8738664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
This case study describes the application of a behavioral weight reduction program to an obese ESRD patient who was also fluid noncompliant. The major purpose of the study was to determine whether the behavioral weight reduction program could be successfully applied to a hemodialysis patient, and if so, what effect reduced caloric intake would have on fluid intake. Based on animal and human studies showing a strong relation between eating and drinking, it was expected that body weight reduction would be accompanied by reduced fluid intake. On the other hand, an alternative psychological hypothesis suggested that increased fluid intake might be substituted for reduced food intake. The results of the weight reduction program indicated that a successful weight reduction of 42 lbs was maintained over an 18-month follow-up period. However, fluid intake increased during periods when caloric intake was reduced. Overall, the results indicated that behavioral weight reduction programs can be successfully applied to weight reduction in obese hemodialysis patients but that ways to avoid increased fluid intake need to be carefully addressed by such programs.
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Affiliation(s)
- N K Wadhwa
- Department of Internal Medicine, State University of New York at Stony Brook 11794-8152, USA
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Edelman R, Eitel P, Wadhwa NK, Friend R, Suh H, Howell N, Cabralda T, Jao E, Aprile-Forlenza S. Accuracy or bias in nurses' ratings of patient compliance: a comparison of treatment modality. Perit Dial Int 1996; 16:321-5. [PMID: 8761549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
OBJECTIVE The study examined the accuracy of nurses' assessments of patient compliance and identified factors influencing these assessments, including possible biases. DESIGN Nurses' assessments of compliance, lab serum levels of dietary compliance, and interdialytic weight gain (IWG) were collected and compared to each other. End-stage renal disease (ESRD) patients on peritoneal dialysis (PD) and hemodialysis (HD) were compared on these measures and their compliance. SETTING The study was conducted at the tertiary care university hospital at Stony Brook. PATIENTS Data were collected for 62 ESRD patients (38 male, 24 female; mean age 54 years). The sample consisted of 26 HD and 36 PD patients. INTERVENTIONS Nurses rated patients' compliance with fluid restrictions (HD patients only) and overall dietary compliance, as well as individual indicators of compliance including protein, potassium, and phosphorus compliance on a 7-point rating scale. Interdialytic weight gain, dietary (serum BUN and K levels), and medication compliance were recorded from charts for a 3-month period for each patient. MAIN OUTCOME MEASURES The main outcome measures were the correlations between nurses' ratings of compliance and medical compliance data and the regression coefficients, which indicate the relative importance of each of the factors that nurses use to make their compliance ratings. RESULTS Nurses' ratings for patients in both treatment modalities were highly correlated with the medical data for measures of fluid (r = 0.66, p < 0.001), potassium (r = 0.36, p < 0.01), and phosphorus (r = 0.36, p < 0.01). A regression analysis indicates that potassium (beta = 0.48, p < 0.001), phosphorus (beta = 0.19, p < 0.05), and protein (beta = 0.31, p < 0.01) all significantly contributed to nurses' assessments of patients' overall compliance. However, nurses' ratings of education levels for patients in both treatment modalities were not associated with phosphorus (r = 0.07, p < 0.61), protein (r = 0.18, p < 0.23), or potassium (r = 0.03, p < 0.85) measures. Finally, regressions revealed that nurses used personal knowledge of the patients when rating noncompliant patients (beta = 0.49, p < 0.05) but not when rating compliant patients (beta = 0.05, p < 0.75). CONCLUSIONS Nurses rely heavily on medical records to rate patients' compliance and to make accurate assessments. Nurses also use several individual indicators (lab values and IWG) to rate overall dietary compliance, suggesting a thorough assessment. While assessments are not biased by personal factors such as nurses' perceptions of patients' education levels, nurses do rely on personal knowledge when rating noncompliant patients.
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Affiliation(s)
- R Edelman
- Department of Psychology, SUNY at Stony Brook, USA
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Abstract
Perceived, but not actual, control over the treatment has been consistently related to better adjustment in chronic illness. This study examined the relationship between actual control over treatment and severity of illness and their influence on depression in a chronically ill population of end-stage renal disease (ESRD) patients. The authors hypothesized that as severity of illness increases, the burden of control over treatment would increase depression. Severity of illness and depression were assessed for 98 ESRD patients. Control over treatment was represented by whether dialysis patients were self-administering treatment (high control) or were receiving treatment from the medical staff (low control). Results indicated that for the most severely ill patients, high control over treatment resulted in poorer adjustment. Furthermore, this effect was due in part to how illness interferes with social relationships in seriously ill, self-care patients.
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Affiliation(s)
- P Eitel
- Department of Psychology, State University of New York at Stony Brook 11794-2500, USA
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30
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Abstract
Perceived, but not actual, control over the treatment has been consistently related to better adjustment in chronic illness. This study examined the relationship between actual control over treatment and severity of illness and their influence on depression in a chronically ill population of end-stage renal disease (ESRD) patients. The authors hypothesized that as severity of illness increases, the burden of control over treatment would increase depression. Severity of illness and depression were assessed for 98 ESRD patients. Control over treatment was represented by whether dialysis patients were self-administering treatment (high control) or were receiving treatment from the medical staff (low control). Results indicated that for the most severely ill patients, high control over treatment resulted in poorer adjustment. Furthermore, this effect was due in part to how illness interferes with social relationships in seriously ill, self-care patients.
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Affiliation(s)
- P Eitel
- Department of Psychology, State University of New York at Stony Brook 11794-2500, USA
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Abstract
The validity of a recently developed measure of disease severity, the End-stage Renal Disease Severity Index (Craven et al. 1991) was examined in haemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) patients (total N = 82). Scores on the ESRD Severity Index were compared with three commonly identified components of disease severity: physiological indices of severity, functional status, and psychological burden of illness. For the entire group of subjects, scores on the ESRD Severity Index were negatively associated with functional ability and positively related to physiological severity. ESRD Severity Index scores showed a weaker relationship with psychological burden of illness which depended in part on treatment mode. Disease severity scores were positively related to depression in CAPD patients but not in HD patients. These findings suggest that the ESRD Severity Index is a valuable research tool with construct validity.
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Affiliation(s)
- K W Griffin
- Department of Psychology, State University of New York at Stony Brook 11794-2500, USA
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McCullough JP, McCune KJ, Kaye AL, Braith JA, Friend R, Roberts WC, Belyea-Caldwell S, Norris SL, Hampton C. One-year prospective replication study of an untreated sample of community dysthymia subjects. J Nerv Ment Dis 1994; 182:396-401. [PMID: 8021639 DOI: 10.1097/00005053-199407000-00005] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This study replicates an earlier naturalistic-prospective investigation of nontreatment, community DSM-III-R dysthymia subjects. Major goals were to determine spontaneous remission rates and monitor the stability of psychosocial functioning levels over time. Twenty-four dysthymia subjects were followed for 1 year. Three remissions (13%) were diagnosed at the final interview. At a 4-year diagnostic follow-up contact with the remitters only, one remitter had relapsed and two remained in remission. Subjects were monitored for depressive symptom intensity, personality functioning, general medical distress, cognitive functioning, coping stylistics, interpersonal functioning, quality of their social support resources, and general family functioning. Stable levels of psychosocial functioning were maintained across all measures over the 1-year period. Current psychometric findings confirm the conclusions of the earlier nontreatment prospective study that dysthymia is a chronic mood disorder with stable psychosocial features and is unlikely to remit spontaneously over time.
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Affiliation(s)
- J P McCullough
- Department of Psychology, Virginia Commonwealth University, Richmond 23284-2018
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McCullough JP, McCune KJ, Kaye AL, Braith JA, Friend R, Roberts WC, Belyea-Caldwell S, Norris SL, Hampton C. Comparison of a community dysthymia sample at screening with a matched group of nondepressed community controls. J Nerv Ment Dis 1994; 182:402-7. [PMID: 8021640 DOI: 10.1097/00005053-199407000-00006] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The primary goal of the study was to compare the psychosocial functioning of an untreated, community sample of DSM-III-R dysthymia subjects (N = 24) at screening to that of a matched sample of community nondepressed volunteers (N = 18) with no lifetime or current history of axis I disorders. Subjects were compared across a number of psychosocial indices. The dysthymics were found to be less sociable (introversion) and clinically high on neuroticism-instability, external in regard to their causal attributions, less stable for positive uncontrollable events and more stable and global for negative uncontrollable events, relying more on coping strategies such as wishful thinking and self-blame, more interpersonally submissive and hostile, and to have a poorer social support-resource network. In addition, the dysthymics reported more family dysfunction and a higher rate of negative major life events.
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Affiliation(s)
- J P McCullough
- Department of Psychology, Virginia Commonwealth University, Richmond 23284-2018
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Abstract
The present study examined how environmental demands, stress, and positive and negative affect were related to health practices. College undergraduates (N = 79) completed measures of stress, mood, and health practices during periods of low and high academic demands. Positive affect was positively related to exercise, nutrition, self-care practices, and overall health practices at two measurement points. Levels of stress (daily hassles, perceived stress, academic stress) increased over time, but increases in daily hassles and perceived stress were unrelated to health practices. Increases in academic demands completed in the previous week were associated with improvements in nutrition and self-care practices, greater drug avoidance, and greater overall health practices. This pattern indicates that a "rebound effect" may occur after high demand periods, during which individuals engage in more health-promoting activities. The results also suggest that the determinants of positive health practices may differ from those of negative health practices.
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Affiliation(s)
- K W Griffin
- Department of Psychology, State University of New York at Stony Brook 11794-2500
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Schneider MS, Friend R, Whitaker P, Wadhwa NK. Fluid noncompliance and symptomatology in end-stage renal disease: Cognitive and emotional variables. Health Psychol 1991; 10:209-15. [PMID: 1879393 DOI: 10.1037/0278-6133.10.3.209] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Fluid noncompliance in patients with end-stage renal disease (ESRD) is a widespread problem with severe consequences for health. In addition, ESRD patients report considerable stress in relation to their illness and dialysis treatment. The present study examined the role of cognitive and emotional variables in fluid noncompliance, symptomatology, and stress. Fifty hemodialysis patients were assessed (a) on the cognitive variables of locus of control, self-evaluations of their past compliance, and self-efficacy to resist fluid intake and (b) on the emotional variables of depression, anger, and anxiety. Results showed that cognitive variables accounted for fluid noncompliance and predicted future adherence. Patients high in negative emotions complied equally as well as patients low in negative emotions but were found to report substantially more symptomatology and distress associated with their treatment. The implications of these findings for treatment of ESRD patients and future research are discussed.
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Affiliation(s)
- M S Schneider
- Department of Psychology, State University of New York, Stony Brook, 11794-2500
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36
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Abstract
The relationship of Cook Medley hostility scores (Ho) to blood pressure and heart rate reactivity was examined in 56 women and 56 men. Stress was elicited by an unsolvable anagram task that was described as easily solvable. Both men and women scoring high on Ho had greater blood pressure responses to the task. Those scoring high on Ho also reported more anger in response to the tasks, but anger was not associated with blood pressure reactivity. It was concluded that situations evoking suspiciousness and mistrust rather than anger may be necessary to elicit increased blood pressure reactivity among high Ho subjects.
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Affiliation(s)
- G Weidner
- Department of Psychology, State University of New York, Stony Brook 11794-2500
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37
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Friend R. Making multilayered samples. Nature 1988. [DOI: 10.1038/331118a0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
All 126 End-Stage Renal Disease (ESRD) patients who entered dialysis between 1971 and 1981 at the Harlem Hospital Center, New York City, were separated into those who had participated in a patient support group and those who had not done so. Patients who engaged in the group activities survived considerably longer than non-participants. Family history of renal disease, psychiatric illness, blood urea nitrogen (BUN), and creatinine were also related to survival, but, education, religion, marital status, and age were not. When 13 psychosocial and physiological covariates were controlled for in a Cox proportional hazard analysis, the group participation effect remained substantial.
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Schneider MS, Friend R, Whitaker P, Wadhwa NK. Fluid noncompliance and symptomatology in end-stage renal disease: cognitive and emotional variables. Psychol Health 1991. [PMID: 1879393 DOI: 10.1037//0278-6133.10.3.209] [Citation(s) in RCA: 10] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Fluid noncompliance in patients with end-stage renal disease (ESRD) is a widespread problem with severe consequences for health. In addition, ESRD patients report considerable stress in relation to their illness and dialysis treatment. The present study examined the role of cognitive and emotional variables in fluid noncompliance, symptomatology, and stress. Fifty hemodialysis patients were assessed (a) on the cognitive variables of locus of control, self-evaluations of their past compliance, and self-efficacy to resist fluid intake and (b) on the emotional variables of depression, anger, and anxiety. Results showed that cognitive variables accounted for fluid noncompliance and predicted future adherence. Patients high in negative emotions complied equally as well as patients low in negative emotions but were found to report substantially more symptomatology and distress associated with their treatment. The implications of these findings for treatment of ESRD patients and future research are discussed.
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Affiliation(s)
- M S Schneider
- Department of Psychology, State University of New York, Stony Brook, 11794-2500
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