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Spungen AM, Dematt EJ, Biswas K, Jones KM, Mi Z, Snodgrass AJ, Morin K, Asselin PK, Cirnigliaro CM, Kirshblum S, Gorman PH, Goetz LL, Stenson K, White KT, Hon A, Sabharwal S, Kiratli BJ, Ota D, Bennett B, Berman JE, Castillo D, Lee KK, Eddy BW, Henzel MK, Trbovich M, Holmes SA, Skelton F, Priebe M, Kornfeld SL, Huang GD, Bauman WA. Exoskeletal-Assisted Walking in Veterans With Paralysis: A Randomized Clinical Trial. JAMA Netw Open 2024; 7:e2431501. [PMID: 39230903 PMCID: PMC11375472 DOI: 10.1001/jamanetworkopen.2024.31501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 06/24/2024] [Indexed: 09/05/2024] Open
Abstract
Importance Robotic exoskeletons leverage technology that assists people with spinal cord injury (SCI) to walk. The efficacy of home and community exoskeletal use has not been studied in a randomized clinical trial (RCT). Objective To examine whether use of a wheelchair plus an exoskeleton compared with use of only a wheelchair led to clinically meaningful net improvements in patient-reported outcomes for mental and physical health. Design, Setting, and Participants This RCT of veterans with SCI was conducted at 15 Veterans Affairs medical centers in the US from September 6, 2016, to September 27, 2021. Data analysis was performed from March 10, 2022, to June 20, 2024. Interventions Participants were randomized (1:1) to standard of care (SOC) wheelchair use or SOC plus at-will use of a US Food and Drug Administration (FDA)-cleared exoskeletal-assisted walking (EAW) device for 4 months in the home and community. Main Outcomes and Measures Two primary outcomes were studied: 4.0-point or greater improvement in the mental component summary score on the Veterans RAND 36-Item Health Survey (MCS/VR-36) and 10% improvement in the total T score of the Spinal Cord Injury-Quality of Life (SCI-QOL) physical and medical health domain and reported as the proportion who achieved clinically meaningful changes. The primary outcomes were measured at baseline, post randomization after advanced EAW training sessions, and at 2 months and 4 months (primary end point) in the intervention period. Device usage, reasons for not using, and adverse events were collected. Results A total of 161 veterans with SCI were randomized to the EAW (n = 78) or SOC (n = 83) group; 151 (94%) were male, the median age was 47 (IQR, 35-56) years, and median time since SCI was 7.3 (IQR, 0.5 to 46.5) years. The difference in proportion of successes between the EAW and SOC groups on the MCS/VR-36 (12 of 78 [15.4%] vs 14 of 83 [16.9%]; relative risk, 0.91; 95% CI, 0.45-1.85) and SCI-QOL physical and medical health domain (10 of 78 [12.8%] vs 11 of 83 [13.3%]; relative risk, 0.97; 95% CI, 0.44-2.15) was not statistically different. Device use was lower than expected (mean [SD] distance, 1.53 [0.02] miles per month), primarily due to the FDA-mandated companion being unavailable 43.9% of the time (177 of 403 instances). Two EAW-related foot fractures and 9 unrelated fractures (mostly during wheelchair transfers) were reported. Conclusions and Relevance In this RCT of veterans with SCI, the lack of improved outcomes with EAW device use may have been related to the relatively low device usage. Solutions for companion requirements and user-friendly technological adaptations should be considered for improved personal use of these devices. Trial Registration ClinicalTrials.gov Identifier: NCT02658656.
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Gikandi A, Tran D, Mi Z, DeMatt E, Quin JA, Kinlay S, Biswas K, Zenati MA. Superior Outcomes of Dual-Arterial Coronary Artery Bypass Grafting Are Maintained in the Veterans Health Administration. J Surg Res 2024; 301:240-246. [PMID: 38970871 DOI: 10.1016/j.jss.2024.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 05/13/2024] [Accepted: 06/16/2024] [Indexed: 07/08/2024]
Abstract
INTRODUCTION Controversy surrounds the long-term clinical benefit of coronary artery bypass grafting (CABG) using dual arterial grafts (DAGs) compared to single arterial grafts (SAGs). We investigated outcomes of DAG, using single internal thoracic artery and radial artery (DAG-RA) or bilateral internal thoracic artery grafts (DAG-BITA), compared to SAG, using the left internal thoracic artery and saphenous vein grafts, in the U.S. Veterans Health Administration (VA). METHODS We conducted a cross-sectional study of U.S. Veterans undergoing isolated on-pump CABG between 2005 and 2015 at 44 VA medical centers. The primary composite outcome was first occurrence of a major adverse cardiac and cerebrovascular event (MACCE), comprised of death from any cause, myocardial infarction, stroke, or repeat revascularization. RESULTS Among 25,969 Veterans undergoing isolated CABG, 1261 (4.9%) underwent DAG (66.8% DAG-RA and 33.2% DAG-BITA). Over a 5-y follow-up, DAG was associated with lower rates of all-cause death (adjusted hazard ratio [AHR] 0.70, 95% confidence interval [CI] 0.58-0.85), MACCE (AHR 0.80, 95% CI 0.71-0.91), and stroke (AHR 0.74, 95% CI 0.57-0.96) versus SAG. DAG-BITA was associated with lower rates of all-cause death (AHR 0.52, 95% CI 0.35-0.77) and MACCE (AHR 0.66, 95% CI 0.51-0.84) than SAG, while DAG-RA was associated with lower rates of all-cause death (AHR 0.79, 95% CI 0.64-0.99). CONCLUSIONS In the VA, DAG was associated with improved long-term MACCE outcomes compared to SAG. These results suggest that the practice of DAG in the VA benefits Veterans and should be promoted further.
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McGonagle K, Dematt EJ, Mi Z, Biswas K, Schroeck FR. Non-Muscle Invasive Bladder Cancer: Many More Patients Die With It Than Of It. Bladder Cancer 2024; 10:113-117. [PMID: 39131873 PMCID: PMC11308635 DOI: 10.3233/blc-230099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 04/06/2024] [Indexed: 08/13/2024]
Abstract
BACKGROUND The National Cancer Institute SEER Program regularly publishes bladder-cancer specific survival statistics. However, this data is for all bladder cancers, and information for non-muscle invasive bladder cancer (NMIBC) is difficult to obtain. OBJECTIVE To quantify 5-year overall and bladder cancer-specific survival in a cohort of Department of Veterans Affairs (VA) patients diagnosed with NMIBC. METHODS We identified VA patients diagnosed with NMIBC who underwent a transurethral resection from 2003-2013. The patient demographics and Charlson Comorbidity Index were categorized. We acquired the patients' date of death from the Veterans Health Administration's Death Ascertainment File and their cause of death from the Mortality Data Repository. We calculated Kaplan Meier estimates of survival. RESULTS A total of 27,008 patients were included; median age was 69 and almost all were male (99%). The median comorbidity score was 4. The most prevalent comorbidity indicators included Chronic Pulmonary Disease (48%), cancer other than Bladder (41%), and diabetes (40%). This cohort was found to have a 5-year overall survival of 68% (99% CI 67% -69%) and a 5-year bladder cancer-specific survival of 93% (99% CI 92% -94%). CONCLUSIONS The 5-year bladder cancer-specific survival in patients diagnosed with non-muscle invasive bladder cancer is substantially higher than the 5-year overall survival. This difference may be related to the severity and number of comorbidities that patients in this population must manage. This warrants further research into the necessity of currently recommended high-intensity cancer surveillance for individuals with NMIBC.
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Beresford TP, Ronan PJ, Taub J, Learned B, Mi Z, Anderson M. Working Toward a Gold Standard: The Severity of Ethanol Withdrawal Scale (SEWS) Versus the Clinical Institute Withdrawal Assessment Alcohol Scale (CIWA-Ar). Alcohol Alcohol 2023; 58:324-328. [PMID: 36935201 PMCID: PMC10168711 DOI: 10.1093/alcalc/agad016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 02/14/2023] [Accepted: 02/14/2023] [Indexed: 03/21/2023] Open
Abstract
AIM Proving the Severity of Ethanol Withdrawal Scale (SEWS) significantly reduces Alcohol Withdrawal Syndrome (AWS) treatment Time on Medication Protocol (TOMP). METHOD Head-to-head Quality Assurance outcome compared separate cohorts of SEWS or Clinical Institute Withdrawal Assessment Alcohol Scale, Revised (CIWA-Ar) data using Student's t and Wilcoxon tests. RESULTS SEWS-driven treatment (n = 244) reduced TOMP to 2.2 days versus 3.4 days for CIWA-Ar (n = 137); P < 0.0001. CONCLUSION The SEWS is the superior measure of AWS symptoms.
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Kougias P, Mi Z, Zhan M, Carson JL, Dosluoglu H, Nelson P, Sarosi GA, Arya S, Norman LE, Sharath S, Scrymgeour A, Ollison J, Calais LA, Biswas K. Transfusion trigger after operations in high cardiac risk patients (TOP) trial protocol. Protocol for a multicenter randomized controlled transfusion strategy trial. Contemp Clin Trials 2023; 126:107095. [PMID: 36690072 DOI: 10.1016/j.cct.2023.107095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 01/13/2023] [Accepted: 01/17/2023] [Indexed: 01/22/2023]
Abstract
BACKGROUND There is substantial uncertainty regarding the effects of restrictive postoperative transfusion among patients who have underlying cardiovascular disease. The TOP Trial's objective is to compare adverse outcomes between liberal and restrictive transfusion strategies in patients undergoing vascular and general surgery operations, and with a high risk of postoperative cardiac events. METHODS A two-arm, single-blinded, randomized controlled superiority trial will be used across 15 Veterans Affairs hospitals with expected enrollment of 1520 participants. Postoperative transfusions in the liberal arm commence when Hb is <10 g/ dL and continue until Hb is greater than or equal to 10 g/dL. In the restrictive arm, transfusions begin when Hb is <7 g/dL and continue until Hb is greater than or equal to 7 g/dL. Study duration is estimated to be 5 years including a 3-month start-up period and 4 years of recruitment. Each randomized participant will be followed for 90 days after randomization with a mortality assessment at 1 year. RESULTS The primary outcome is a composite endpoint of all-cause mortality, myocardial infarction (MI), coronary revascularization, acute renal failure, or stroke occurring up to 90-days after randomization. Events rates will be compared between restrictive and liberal transfusion groups. CONCLUSIONS The TOP Trial is uniquely positioned to provide high quality evidence comparing transfusion strategies among patients with high cardiac risk. Results will clarify the effect of postoperative transfusion strategies on adverse outcomes and inform postoperative management algorithms. TRIAL REGISTRATION http://clinicaltrials.gov identifier: NCT03229941.
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Nickols NG, Mi Z, DeMatt E, Biswas K, Clise CE, Huggins JT, Maraka S, Ambrogini E, Mirsaeidi MS, Levin ER, Becker DJ, Makarov DV, Adorno Febles V, Belligund PM, Al-Ajam M, Muthiah MP, Montgomery RB, Robinson KW, Wong YN, Bedimo RJ, Villareal RC, Aguayo SM, Schoen MW, Goetz MB, Graber CJ, Bhattacharya D, Soo Hoo G, Orshansky G, Norman LE, Tran S, Ghayouri L, Tsai S, Geelhoed M, Rettig MB. Effect of Androgen Suppression on Clinical Outcomes in Hospitalized Men With COVID-19: The HITCH Randomized Clinical Trial. JAMA Netw Open 2022; 5:e227852. [PMID: 35438754 PMCID: PMC9020208 DOI: 10.1001/jamanetworkopen.2022.7852] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
IMPORTANCE SARS-CoV-2 entry requires the TMPRSS2 cell surface protease. Antiandrogen therapies reduce expression of TMPRSS2. OBJECTIVE To determine if temporary androgen suppression induced by degarelix improves clinical outcomes of inpatients hospitalized with COVID-19. DESIGN, SETTING, AND PARTICIPANTS The Hormonal Intervention for the Treatment in Veterans With COVID-19 Requiring Hospitalization (HITCH) phase 2, placebo-controlled, double-blind, randomized clinical trial compared efficacy of degarelix plus standard care vs placebo plus standard care on clinical outcomes in men hospitalized with COVID-19 but not requiring invasive mechanical ventilation. Inpatients were enrolled at 14 Department of Veterans Affairs hospitals from July 22, 2020, to April 8, 2021. Data were analyzed from August 9 to October 15, 2021. INTERVENTIONS Patients stratified by age, history of hypertension, and disease severity were centrally randomized 2:1 to degarelix, (1-time subcutaneous dose of 240 mg) or a saline placebo. Standard care included but was not limited to supplemental oxygen, antibiotics, vasopressor support, peritoneal dialysis or hemodialysis, intravenous fluids, remdesivir, convalescent plasma, and dexamethasone. MAIN OUTCOMES AND MEASURES The composite primary end point was mortality, ongoing need for hospitalization, or requirement for mechanical ventilation at day 15 after randomization. Secondary end points were time to clinical improvement, inpatient mortality, length of hospitalization, duration of mechanical ventilation, time to achieve a temperature within reference range, maximum severity of COVID-19, and the composite end point at 30 days. RESULTS The trial was stopped for futility after the planned interim analysis, at which time there were 96 evaluable patients, including 62 patients randomized to the degarelix group and 34 patients in the placebo group, out of 198 initially planned. The median (range) age was 70.5 (48-85) years. Common comorbidities included chronic obstructive pulmonary disorder (15 patients [15.6%]), hypertension (75 patients [78.1%]), cardiovascular disease (27 patients [28.1%]), asthma (12 patients [12.5%]), diabetes (49 patients [51.0%]), and chronic respiratory failure requiring supplemental oxygen at baseline prior to COVID-19 (9 patients [9.4%]). For the primary end point, there was no significant difference between the degarelix and placebo groups (19 patients [30.6%] vs 9 patients [26.5%]; P = .67). Similarly, no differences were observed between degarelix and placebo groups in any secondary end points, including inpatient mortality (11 patients [17.7%] vs 6 patients [17.6%]) or all-cause mortality (11 patients [17.7%] vs 7 patents [20.6%]). There were no differences between degarelix and placebo groups in the overall rates of adverse events (13 patients [21.0%] vs 8 patients [23.5%) and serious adverse events (19 patients [30.6%] vs 13 patients [32.4%]), nor unexpected safety concerns. CONCLUSIONS AND RELEVANCE In this randomized clinical trial of androgen suppression vs placebo and usual care for men hospitalized with COVID-19, degarelix did not result in amelioration of COVID-19 severity. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT04397718.
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Nickols NG, Goetz MB, Graber CJ, Bhattacharya D, Soo Hoo G, Might M, Goldstein DB, Wang X, Ramoni R, Myrie K, Tran S, Ghayouri L, Tsai S, Geelhoed M, Makarov D, Becker DJ, Tsay JC, Diamond M, George A, Al-Ajam M, Belligund P, Montgomery RB, Mostaghel EA, Sulpizio C, Mi Z, Dematt E, Tadalan J, Norman LE, Briones D, Clise CE, Taylor ZW, Huminik JR, Biswas K, Rettig MB. Hormonal intervention for the treatment of veterans with COVID-19 requiring hospitalization (HITCH): a multicenter, phase 2 randomized controlled trial of best supportive care vs best supportive care plus degarelix: study protocol for a randomized controlled trial. Trials 2021; 22:431. [PMID: 34225789 PMCID: PMC8256647 DOI: 10.1186/s13063-021-05389-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 06/21/2021] [Indexed: 12/03/2022] Open
Abstract
Background Therapeutic targeting of host-cell factors required for SARS-CoV-2 entry is an alternative strategy to ameliorate COVID-19 severity. SARS-CoV-2 entry into lung epithelium requires the TMPRSS2 cell surface protease. Pre-clinical and correlative data in humans suggest that anti-androgenic therapies can reduce the expression of TMPRSS2 on lung epithelium. Accordingly, we hypothesize that therapeutic targeting of androgen receptor signaling via degarelix, a luteinizing hormone-releasing hormone (LHRH) antagonist, will suppress COVID-19 infection and ameliorate symptom severity. Methods This is a randomized phase 2, placebo-controlled, double-blind clinical trial in 198 patients to compare efficacy of degarelix plus best supportive care versus placebo plus best supportive care on improving the clinical outcomes of male Veterans who have been hospitalized due to COVID-19. Enrolled patients must have documented infection with SARS-CoV-2 based on a positive reverse transcriptase polymerase chain reaction result performed on a nasopharyngeal swab and have a severity of illness of level 3–5 (hospitalized but not requiring invasive mechanical ventilation). Patients stratified by age, history of hypertension, and severity are centrally randomized 2:1 (degarelix: placebo). The composite primary endpoint is mortality, ongoing need for hospitalization, or requirement for mechanical ventilation at 15 after randomization. Important secondary endpoints include time to clinical improvement, inpatient mortality, length of hospitalization, duration of mechanical ventilation, time to achieve a normal temperature, and the maximum severity of COVID-19 illness. Exploratory analyses aim to assess the association of cytokines, viral load, and various comorbidities with outcome. In addition, TMPRSS2 expression in target tissue and development of anti-viral antibodies will also be investigated. Discussion In this trial, we repurpose the FDA approved LHRH antagonist degarelix, commonly used for prostate cancer, to suppress TMPRSS2, a host cell surface protease required for SARS-CoV-2 cell entry. The objective is to determine if temporary androgen suppression with a single dose of degarelix improves the clinical outcomes of patients hospitalized due to COVID-19. Trial registration ClinicalTrials.gov NCT04397718. Registered on May 21, 2020
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Mi Z, Sun Z, Huang Z, Zhao P, Li Q, Tian P. Engineering CRISPR interference system to enhance the production of pyrroloquinoline quinone in Klebsiella pneumonia. Lett Appl Microbiol 2020; 71:242-250. [PMID: 32394472 DOI: 10.1111/lam.13311] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 05/05/2020] [Accepted: 05/05/2020] [Indexed: 11/28/2022]
Abstract
Pyrroloquinoline quinone (PQQ) is a cofactor of glucose dehydrogenase (GDH) and thus participates in glucose utilization. In Klebsiella pneumoniae, glucose utilization involves PQQ-dependent direct oxidation pathway (DOP) and phosphoenolpyruvate-dependent transport system (PTS). It is challenging to overproduce PQQ, as its biosynthesis remains unclear. Here, we report that PQQ production can be enhanced by stimulating the metabolic demand for it. First, we developed CRISPR interference (CRISPRi) system to block PTS and thereby intensify DOP. In shake-flask cultivation, the strain with CRISPRi system (simultaneously inhibiting four PTS-related genes) produced 225·65 nmol l-1 PQQ, which was 2·14 times that of wild type. In parallel, an exogenous soluble glucose dehydrogenase (sGDH) was overexpressed in K. pneumoniae. In the shake-flask cultivation, this sGDH-overexpressing strain accumulated 140·05 nmol l-1 PQQ, which was 1·33 times that of wild type. To combine the above two strategies, we engineered a strain harbouring both CRISPRi vector and sGDH-overexpressing vector. In the shake-flask cultivation, this two-plasmid strain generated 287·01 nmol l-1 PQQ, which was 2·72 times that of wild type. In bioreactor cultivation, this two-plasmid strain produced 2206·1 nmol l-1 PQQ in 57 h, which was 7·69 times that in shake-flask cultivation. These results indicate that PQQ production can be enhanced by intensifying DOP, as the apo-enzyme GDH is intrinsically coupled with cofactor PQQ. This study provides a strategy for the production of cofactors whose biosynthesis mechanisms remain ambiguous. SIGNIFICANCE AND IMPACT OF THE STUDY: Pyrroloquinoline quinone (PQQ) is an economically important chemical, which typically serves as a cofactor of glucose dehydrogenase (GDH) and thus participates in glucose metabolism. Klebsiella pneumoniae can naturally synthesize PQQ, but current yield constrains its commercialization. In this study, the PQQ level was improved by stimulating metabolic demand for PQQ, instead of overexpressing PQQ synthetic genes, as the synthetic mechanism remains ambiguous.
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Pandey A, Shin WJ, Liu X, Mi Z. Effect of electron blocking layer on the efficiency of AlGaN mid-ultraviolet light emitting diodes. OPTICS EXPRESS 2019; 27:A738-A745. [PMID: 31252850 DOI: 10.1364/oe.27.00a738] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 04/09/2019] [Indexed: 06/09/2023]
Abstract
The performance of AlGaN-based mid and deep ultraviolet light emitting diodes (LEDs) is severely limited by electron overflow and by the poor hole injection into the device active region. We have studied the effect of various electron blocking layers on the performance of AlGaN LEDs operating at ~280 nm. It is observed that, compared to conventional p-type electron blocking layer, the incorporation of an n-type AlN/AlGaN superlattice electron blocking layer before the active region can significantly improve the device performance by reducing electron overflow without compromising hole injection. Direct on-wafer measurement showed an external quantum efficiency ~4.4% and wall-plug efficiency ~2.8% by optimizing the design of n-type AlN/AlGaN superlattice electron blocking layer, which is nearly a factor of five to ten times better than identical devices but with the incorporation of a conventional p-type electron blocking layer.
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Sadaf SM, Ra YH, Zhao S, Szkopek T, Mi Z. Structural and electrical characterization of monolithic core-double shell n-GaN/Al/p-AlGaN nanowire heterostructures grown by molecular beam epitaxy. NANOSCALE 2019; 11:3888-3895. [PMID: 30758042 DOI: 10.1039/c9nr00081j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We have studied the epitaxy and structural characterization of monolithic n-GaN/Al/p-AlGaN nanowire heterostructures. It is found that high quality, nearly defect free, full shell epitaxial Al can be grown in situ on Al(Ga)N nanowires and vice versa. Detailed scanning transmission electron microscopy (STEM), high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) suggest that the Al (111) plane maintains an epitaxial relationship with Al(Ga)N (0001) in the nanowire growth direction. Full ultraviolet composition range (340 nm-210 nm) Al/Al(Ga)N core-double shell nanowire backward diode characteristics were investigated. We have demonstrated a monolithic n++-GaN/Al/p++-Al(Ga)N nanowire backward diode, wherein an epitaxial Al layer serves as the tunnel junction. Such an Al(Ga)N-based n-p-n nanowire backward diode exhibits record low resistivity (<1.5 × 10-4Ω cm2) and a low turn-on voltage of ∼2.7 V.
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Le BH, Liu X, Tran NH, Zhao S, Mi Z. An electrically injected AlGaN nanowire defect-free photonic crystal ultraviolet laser. OPTICS EXPRESS 2019; 27:5843-5850. [PMID: 30876179 DOI: 10.1364/oe.27.005843] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 11/09/2018] [Indexed: 06/09/2023]
Abstract
We report on the demonstration of an electrically injected AlGaN nanowire photonic crystal laser that can operate in the ultraviolet spectral range. The nanowire heterostructures were grown on sapphire substrate using a site-controlled selective area growth process. By exploiting the topological high-Q resonance of a defect-free nanowire photonic crystal, we have demonstrated electrically pumped lasers that can operate at 369.5 nm with a relatively low threshold current density of ~2.1 kA/cm2 under continuous wave operation at room-temperature. This work provides a promising approach for achieving low threshold semiconductor laser diodes operating in the UV spectral range that were previously difficult.
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Meuret S, Solà Garcia M, Coenen T, Kieft E, Zeijlemaker H, Lätzel M, Christiansen S, Woo SY, Ra YH, Mi Z, Polman A. Complementary cathodoluminescence lifetime imaging configurations in a scanning electron microscope. Ultramicroscopy 2018; 197:28-38. [PMID: 30476703 DOI: 10.1016/j.ultramic.2018.11.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Revised: 11/09/2018] [Accepted: 11/13/2018] [Indexed: 11/29/2022]
Abstract
Cathodoluminescence (CL) spectroscopy provides a powerful way to characterize optical properties of materials with deep-subwavelength spatial resolution. While CL imaging to obtain optical spectra is a well-developed technology, imaging CL lifetimes with nanoscale resolution has only been explored in a few studies. In this paper we compare three different time-resolved CL techniques and compare their characteristics. Two configurations are based on the acquisition of CL decay traces using a pulsed electron beam that is generated either with an ultra-fast beam blanker, which is placed in the electron column, or by photoemission from a laser-driven electron cathode. The third configuration uses measurements of the autocorrelation function g(2) of the CL signal using either a continuous or a pulsed electron beam. The three techniques are compared in terms of complexity of implementation, spatial and temporal resolution, and measurement accuracy as a function of electron dose. A single sample of InGaN/GaN quantum wells is investigated to enable a direct comparison of lifetime measurement characteristics of the three techniques. The g(2)-based method provides decay measurements at the best spatial resolution, as it leaves the electron column configuration unaffected. The pulsed-beam methods provide better detail on the temporal excitation and decay dynamics. The ultra-fast blanker configuration delivers electron pulses as short as 30 ps at 5 keV and 250 ps at 30 keV. The repetition rate can be chosen arbitrarily up to 80 MHz and requires a conjugate plane geometry in the electron column that reduces the spatial resolution in our microscope. The photoemission configuration, pumped with 250 fs 257 nm pulses at a repetition rate from 10 kHz to 25 MHz, allows creation of electron pulses down to a few ps, with some loss in spatial resolution.
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Yesavage JA, Fairchild JK, Mi Z, Biswas K, Davis-Karim A, Phibbs CS, Forman SD, Thase M, Williams LM, Etkin A, O’Hara R, Georgette G, Beale T, Huang GD, Noda A, George MS. Effect of Repetitive Transcranial Magnetic Stimulation on Treatment-Resistant Major Depression in US Veterans: A Randomized Clinical Trial. JAMA Psychiatry 2018; 75:884-893. [PMID: 29955803 PMCID: PMC6142912 DOI: 10.1001/jamapsychiatry.2018.1483] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
IMPORTANCE Treatment-resistant major depression (TRMD) in veterans is a major clinical challenge given the high risk for suicidality in these patients. Repetitive transcranial magnetic stimulation (rTMS) offers the potential for a novel treatment modality for these veterans. OBJECTIVE To determine the efficacy of rTMS in the treatment of TRMD in veterans. DESIGN, SETTING, AND PARTICIPANTS A double-blind, sham-controlled randomized clinical trial was conducted from September 1, 2012, to December 31, 2016, in 9 Veterans Affairs medical centers. A total of 164 veterans with TRD participated. INTERVENTIONS Participants were randomized to either left prefrontal rTMS treatment (10 Hz, 120% motor threshold, 4000 pulses/session) or to sham (control) rTMS treatment for up to 30 treatment sessions. MAIN OUTCOMES AND MEASURES The primary dependent measure of the intention-to-treat analysis was remission rate (Hamilton Rating Scale for Depression score ≤10, indicating that depression is in remission and not a clinically significant burden), and secondary analyses were conducted on other indices of posttraumatic stress disorder, depression, hopelessness, suicidality, and quality of life. RESULTS The 164 participants had a mean (SD) age of 55.2 (12.4) years, 132 (80.5%) were men, and 126 (76.8%) were of white race. Of these, 81 were randomized to receive active rTMS and 83 to receive sham. For the primary analysis of remission, there was no significant effect of treatment (odds ratio, 1.16; 95% CI, 0.59-2.26; P = .67). At the end of the acute treatment phase, 33 of 81 (40.7%) of those in the active treatment group achieved remission of depressive symptoms compared with 31 of 83 (37.4%) of those in the sham treatment group. Overall, 64 of 164 (39.0%) of the participants achieved remission. CONCLUSIONS AND RELEVANCE A total of 39.0% of the veterans who participated in this trial experienced clinically significant improvement resulting in remission of depressive symptoms; however, there was no evidence of difference in remission rates between the active and sham treatments. These findings may reflect the importance of close clinical surveillance, rigorous monitoring of concomitant medication, and regular interaction with clinic staff in bringing about significant improvement in this treatment-resistant population. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT01191333.
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Wang Z, Mi Z, Wang H, Sun L, Yu G, Fu X, Wang C, Bao F, Yue Z, Zhao Q, Wang N, Cheng X, Liu H, Zhang F. Discovery of 4 exonic and 1 intergenic novel susceptibility loci for leprosy. Clin Genet 2018; 94:259-263. [PMID: 29722023 DOI: 10.1111/cge.13376] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 04/26/2018] [Accepted: 05/01/2018] [Indexed: 12/13/2022]
Abstract
Seven new risk coding variants have been identified through an exome-wide association study (EWAS), which studied the contributions of protein-coding variants to leprosy susceptibility. But some potential susceptibility loci were not studied in the previous EWAS study because of the project consideration. Seventeen unstudied potential susceptibility loci of the previous EWAS were validated in 3169 cases and 9814 controls in this study. Four disease-associated exonic loci were identified: rs671 in ALDH2 (P = 2.0 × 10-20 , odds ratio [OR] = 1.35), rs13259978 in SLC7A2 (P = 1.74 × 10-8 , OR = 1.28), rs925368 in GIT2 (P = 9.18 × 10-17 , OR = 1.44), and rs75680863 in TCN2 (P = 8.37 × 10-21 , OR = 0.74). Potentially implicating ZFP36L1 as a new susceptibility gene, 1 intergenic single nucleotide polymorphism (SNP), rs1465788 (P = 7.81 × 10-6 , OR = 0.88), was also suggested to be associated with leprosy. A luciferase reporter assay showed that the rs1465788 risk allele notably decreased the transcription activity of the flanking sequence. These findings suggest the possible involvement of lipid metabolism, NF-κB homeostasis and macrophage antimicrobial pathways in leprosy pathogenesis.
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Mi Z, Biswas K, Fairchild JK, Davis-Karim A, Phibbs CS, Forman SD, Thase M, Georgette G, Beale T, Pittman D, McNerney MW, Rosen A, Huang GD, George M, Noda A, Yesavage JA. Repetitive transcranial magnetic stimulation (rTMS) for treatment-resistant major depression (TRMD) Veteran patients: study protocol for a randomized controlled trial. Trials 2017; 18:409. [PMID: 28865495 PMCID: PMC5581925 DOI: 10.1186/s13063-017-2125-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 08/02/2017] [Indexed: 01/29/2023] Open
Abstract
Background Evaluation of repetitive transcranial magnetic stimulation (rTMS) for treatment-resistant major depression (TRMD) in Veterans offers unique clinical trial challenges. Here we describe a randomized, double-blinded, intent-to-treat, two-arm, superiority parallel design, a multicenter study funded by the Cooperative Studies Program (CSP No. 556) of the US Department of Veterans Affairs. Methods We recruited medical providers with clinical expertise in treating TRMD at nine Veterans Affairs (VA) medical centers as the trial local investigators. We plan to enroll 360 Veterans diagnosed with TRMD at the nine VA medical centers over a 3-year period. We will randomize participants into a double-blinded clinical trial to left prefrontal rTMS treatment or to sham (control) rTMS treatment (180 participants each group) for up to 30 treatment sessions. All participants will meet Diagnostic and statistical manual of mental disorders, 4thedition (DSM-IV) criteria for major depression and will have failed at least two prior pharmacological interventions. In contrast with other rTMS clinical trials, we will not exclude Veterans with posttraumatic stress disorder (PTSD) or history of substance abuse and we will obtain detailed history regarding these disorders. Furthermore, we will maintain participants on stable anti-depressant medication throughout the trial. We will evaluate all participants on a wide variety of potential predictors of treatment response including cognitive, psychological and functional parameters. Discussion The primary dependent measure will be remission rate (Hamilton Rating Scale for Depression (HRSD24) ≤ 10), and secondary analyses will be conducted on other indices. Comparisons between the rTMS and the sham groups will be made at the end of the acute treatment phase to test the primary hypothesis. The unique challenges to performing such a large technically challenging clinical trial with Veterans and potential avenues for improvement of the design in future trials will be described. Trial registration ClinicalTrials.gov, NCT01191333. Registered on 26 August 2010. This report is based on the protocol version 4.6 amended in February 2016. All items from the World Health Organization Trial Registration Data Set are listed in Appendix A. Electronic supplementary material The online version of this article (doi:10.1186/s13063-017-2125-y) contains supplementary material, which is available to authorized users.
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Sadaf SM, Zhao S, Wu Y, Ra YH, Liu X, Vanka S, Mi Z. An AlGaN Core-Shell Tunnel Junction Nanowire Light-Emitting Diode Operating in the Ultraviolet-C Band. NANO LETTERS 2017; 17:1212-1218. [PMID: 28081598 DOI: 10.1021/acs.nanolett.6b05002] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
To date, semiconductor light emitting diodes (LEDs) operating in the deep ultraviolet (UV) spectral range exhibit very low efficiency due to the presence of large densities of defects and extremely inefficient p-type conduction of conventional AlGaN quantum well heterostructures. We have demonstrated that such critical issues can be potentially addressed by using nearly defect-free AlGaN tunnel junction core-shell nanowire heterostructures. The core-shell nanowire arrays exhibit high photoluminescence efficiency (∼80%) in the UV-C band at room temperature. With the incorporation of an epitaxial Al tunnel junction, the p-(Al)GaN contact-free nanowire deep UV LEDs showed nearly one order of magnitude reduction in the device resistance, compared to the conventional nanowire p-i-n device. The unpackaged Al tunnel junction deep UV LEDs exhibit an output power >8 mW and a peak external quantum efficiency ∼0.4%, which are nearly one to two orders of magnitude higher than previously reported AlGaN nanowire devices. Detailed studies further suggest that the maximum achievable efficiency is limited by electron overflow and poor light extraction efficiency due to the TM polarized emission.
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Novitzky D, Mi Z, Videla LA, Collins JF, Cooper DKC. Thyroid hormone therapy and procurement of livers from brain-dead donors. Endocr Res 2016; 41:270-3. [PMID: 26853445 DOI: 10.3109/07435800.2015.1111902] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Hormonal therapy to brain-dead potential organ donors remains controversial. A retrospective study was carried out of hormonal therapy on procurement of organs in 63,593 donors in whom information on T3/T4 therapy was available. In 40,124 donors, T3/T4 and all other hormonal therapy was recorded. The percentages of all organs procured, except livers, were greater in T3/T4-treated donors. Nevertheless, if T3/T4 therapy had been administered to the donor, liver transplantation was associated with significantly increased graft and recipient survival at 1 month and 12 months. The potential reasons for the lack of effect of T3/T4 therapy on the number of livers procured are discussed.
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Novitzky D, Mi Z, Videla LA, Collins JF, Cooper DKC. Hormone resuscitation therapy for brain-dead donors - is insulin beneficial or detrimental? Clin Transplant 2016; 30:754-9. [DOI: 10.1111/ctr.12742] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2016] [Indexed: 01/23/2023]
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Sadaf SM, Ra YH, Szkopek T, Mi Z. Monolithically Integrated Metal/Semiconductor Tunnel Junction Nanowire Light-Emitting Diodes. NANO LETTERS 2016; 16:1076-1080. [PMID: 26812264 DOI: 10.1021/acs.nanolett.5b04215] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We have demonstrated for the first time an n(++)-GaN/Al/p(++)-GaN backward diode, wherein an epitaxial Al layer serves as the tunnel junction. The resulting p-contact free InGaN/GaN nanowire light-emitting diodes (LEDs) exhibited a low turn-on voltage (∼2.9 V), reduced resistance, and enhanced power, compared to nanowire LEDs without the use of Al tunnel junction or with the incorporation of an n(++)-GaN/p(++)-GaN tunnel junction. This unique Al tunnel junction overcomes some of the critical issues related to conventional GaN-based tunnel junction designs, including stress relaxation, wide depletion region, and light absorption, and holds tremendous promise for realizing low-resistivity, high-brightness III-nitride nanowire LEDs in the visible and deep ultraviolet spectral range. Moreover, the demonstration of monolithic integration of metal and semiconductor nanowire heterojunctions provides a seamless platform for realizing a broad range of multifunctional nanoscale electronic and photonic devices.
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Zhao S, Woo SY, Bugnet M, Liu X, Kang J, Botton GA, Mi Z. Three-Dimensional Quantum Confinement of Charge Carriers in Self-Organized AlGaN Nanowires: A Viable Route to Electrically Injected Deep Ultraviolet Lasers. NANO LETTERS 2015; 15:7801-7. [PMID: 26539880 DOI: 10.1021/acs.nanolett.5b02133] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
We report on the molecular beam epitaxial growth and structural characterization of self-organized AlGaN nanowire arrays on Si substrate with high luminescence efficiency emission in the deep ultraviolet (UV) wavelength range. It is found that, with increasing Al concentration, atomic-scale compositional modulations can be realized, leading to three-dimensional quantum confinement of charge carriers. By further exploiting the Anderson localization of light, we have demonstrated, for the first time, electrically injected AlGaN lasers in the deep UV band operating at room temperature. The laser operates at ∼289 nm and exhibits a threshold of 300 A/cm(2), which is significantly smaller compared to the previously reported electrically injected AlGaN multiple quantum well lasers.
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AlOtaibi B, Fan S, Vanka S, Kibria MG, Mi Z. A Metal-Nitride Nanowire Dual-Photoelectrode Device for Unassisted Solar-to-Hydrogen Conversion under Parallel Illumination. NANO LETTERS 2015; 15:6821-6828. [PMID: 26360182 DOI: 10.1021/acs.nanolett.5b02671] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A dual-photoelectrode device, consisting of a photoanode and photocathode with complementary energy bandgaps, has long been perceived as an ideal scheme for achieving high efficiency, unassisted solar-driven water splitting. Previously reported 2-photon tandem devices, however, generally exhibit an extremely low efficiency (<0.1%), which has been largely limited by the incompatibility between the two photoelectrode materials. Here we show that the use of metal-nitride nanowire photoelectrodes, together with the scheme of parallel illumination by splitting the solar spectrum spatially and spectrally, can break the efficiency bottleneck of conventional 2-photon tandem devices. We have first investigated a dual-photoelectrode device consisting of a GaN nanowire photoanode and an InGaN nanowire photocathode, which exhibited an open circuit potential of 1.3 V and nearly 20-fold enhancement in the power conversion efficiency under visible light illumination (400-600 nm), compared to the individual photoelectrodes in 1 mol/L HBr. We have further demonstrated a dual-photoelectrode device consisting of parallel-connected metal-nitride nanowire photoanodes and a Si/InGaN nanowire photocathode, which can perform unassisted, direct solar-to-hydrogen conversion. A power conversion efficiency of 2% was measured under AM1.5G 1 sun illumination.
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Zhao S, Djavid M, Mi Z. Surface Emitting, High Efficiency Near-Vacuum Ultraviolet Light Source with Aluminum Nitride Nanowires Monolithically Grown on Silicon. NANO LETTERS 2015; 15:7006-7009. [PMID: 26375576 DOI: 10.1021/acs.nanolett.5b03040] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
To date, it has remained challenging to realize electrically injected light sources in the vacuum ultraviolet wavelength range (∼200 nm or shorter), which are important for a broad range of applications, including sensing, surface treatment, and photochemical analysis. In this Letter, we have demonstrated such a light source with molecular beam epitaxially grown aluminum nitride (AlN) nanowires on low cost, large area Si substrate. Detailed angle dependent electroluminescence studies suggest that, albeit the light is TM polarized, the dominant light emission direction is from the nanowire top surface, that is, along the c axis, due to the strong light scattering effect. Such an efficient surface emitting device was not previously possible using conventional c-plane AlN planar structures. The AlN nanowire LEDs exhibit an extremely large electrical efficiency (>85%), which is nearly ten times higher than the previously reported AlN planar devices. Our detailed studies further suggest that the performance of AlN nanowire LEDs is predominantly limited by electron overflow. This study provides important insight on the fundamental emission characteristics of AlN nanowire LEDs and also offers a viable path to realize an efficient surface emitting near-vacuum ultraviolet light source through direct electrical injection.
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Sadaf SM, Ra YH, Nguyen HPT, Djavid M, Mi Z. Alternating-Current InGaN/GaN Tunnel Junction Nanowire White-Light Emitting Diodes. NANO LETTERS 2015; 15:6696-701. [PMID: 26384135 DOI: 10.1021/acs.nanolett.5b02515] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The current LED lighting technology relies on the use of a driver to convert alternating current (AC) to low-voltage direct current (DC) power, a resistive p-GaN contact layer to inject positive charge carriers (holes) for blue light emission, and rare-earth doped phosphors to down-convert blue photons into green/red light, which have been identified as some of the major factors limiting the device efficiency, light quality, and cost. Here, we show that multiple-active region phosphor-free InGaN nanowire white LEDs connected through a polarization engineered tunnel junction can fundamentally address the afore-described challenges. Such a p-GaN contact-free LED offers the benefit of carrier regeneration, leading to enhanced light intensity and reduced efficiency droop. Moreover, through the monolithic integration of p-GaN up and p-GaN down nanowire LED structures on the same substrate, we have demonstrated, for the first time, AC operated LEDs on a Si platform, which can operate efficiently in both polarities (positive and negative) of applied voltage.
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Kibria MG, Chowdhury FA, Trudeau ML, Guo H, Mi Z. Dye-sensitized InGaN nanowire arrays for efficient hydrogen production under visible light irradiation. NANOTECHNOLOGY 2015; 26:285401. [PMID: 26120103 DOI: 10.1088/0957-4484/26/28/285401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Solar water splitting is a key sustainable energy technology for clean, storable and renewable source of energy in the future. Here we report that Merocyanine-540 dye-sensitized and Rh nanoparticle-decorated molecular beam epitaxially grown In0.25Ga0.75N nanowire arrays have produced hydrogen from ethylenediaminetetraacetic acid (EDTA) and acetonitrile mixture solution under green, yellow and orange solar spectra (up to 610 nm) for the first time. An apparent quantum efficiency of 0.3% is demonstrated for wavelengths 525-600 nm, providing a viable approach to harness deep-visible and near-infrared solar energy for efficient and stable water splitting.
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Novitzky D, Mi Z, Collins JF, Cooper DKC. Increased Procurement of Thoracic Donor Organs After Thyroid Hormone Therapy. Semin Thorac Cardiovasc Surg 2015; 27:123-32. [PMID: 26686437 DOI: 10.1053/j.semtcvs.2015.06.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2015] [Indexed: 12/17/2022]
Abstract
Hormonal therapy to the brain-dead organ donor can include thyroid hormone (triiodothyronine [T3] or levothyroxine [T4]), antidiuretic hormone, corticosteroids, or insulin. There has been a controversy on whether thyroid hormone enables more organs to be procured. Data on 63,593 donors of hearts and lungs (2000-2009) were retrospectively reviewed. Documentation on T3/T4 was available in all donors (study 1), and in 40,124 details of all 4 hormones were recorded (study 2). In this cohort, group A (23,022) received T3/T4 and group B (17,102) no T3/T4. Univariate analyses and multiple regressions were performed. Posttransplant graft and recipient survival at 1 and 12 months were compared. In study 1, 30,962 donors received T3/T4, with 36.59% providing a heart and 20.05% providing 1 or both lungs. Of the 32,631 donors who did not receive T3/T4, only 29.62% provided a heart and 14.61% provided lungs, an increase of 6.97% hearts and 5.44% lungs from T3/T4-treated donors (both P < 0.0001). In study 2, 34.99% of group A provided a heart and 20.99% provided lungs. In group B only 25.76% provided a heart and 15.09% provided lungs, an increase of 9.23% (hearts) and 5.90% (lungs), respectively, in group A (both P < 0.0001). The results of multiple regression analyses indicated a beneficial effect of T3/T4 on heart (P < 0.0001) and lung (P < 0.0001) procurement independent of other factors. T3/T4 therapy to the donor was associated with either improved posttransplant graft and recipient survival or no difference in survival. T3/T4 therapy results in more transplantable hearts and lungs, with no detriment to posttransplant graft or recipient survival.
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