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Elsayed MH, Abdellah M, Alhakemy AZ, Mekhemer IMA, Aboubakr AEA, Chen BH, Sabbah A, Lin KH, Chiu WS, Lin SJ, Chu CY, Lu CH, Yang SD, Mohamed MG, Kuo SW, Hung CH, Chen LC, Chen KH, Chou HH. Overcoming small-bandgap charge recombination in visible and NIR-light-driven hydrogen evolution by engineering the polymer photocatalyst structure. Nat Commun 2024; 15:707. [PMID: 38267492 PMCID: PMC10808228 DOI: 10.1038/s41467-024-45085-6] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 01/15/2024] [Indexed: 01/26/2024] Open
Abstract
Designing an organic polymer photocatalyst for efficient hydrogen evolution with visible and near-infrared (NIR) light activity is still a major challenge. Unlike the common behavior of gradually increasing the charge recombination while shrinking the bandgap, we present here a series of polymer nanoparticles (Pdots) based on ITIC and BTIC units with different π-linkers between the acceptor-donor-acceptor (A-D-A) repeated moieties of the polymer. These polymers act as an efficient single polymer photocatalyst for H2 evolution under both visible and NIR light, without combining or hybridizing with other materials. Importantly, the difluorothiophene (ThF) π-linker facilitates the charge transfer between acceptors of different repeated moieties (A-D-A-(π-Linker)-A-D-A), leading to the enhancement of charge separation between D and A. As a result, the PITIC-ThF Pdots exhibit superior hydrogen evolution rates of 279 µmol/h and 20.5 µmol/h with visible (>420 nm) and NIR (>780 nm) light irradiation, respectively. Furthermore, PITIC-ThF Pdots exhibit a promising apparent quantum yield (AQY) at 700 nm (4.76%).
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Affiliation(s)
- Mohamed Hammad Elsayed
- Department of Chemistry, Faculty of Science, Al-Azhar University, Nasr City, 11884, Cairo, Egypt
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
- Center for Condensed Matter Sciences, National Taiwan University, Taipei, 10617, Taiwan
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Mohamed Abdellah
- Department of Chemistry, United Arab Emirates University, Al Ain, P.O. Box 15551, United Arab Emirates
- Department of Chemistry, Qena Faculty of Science, South Valley University, 83523, Qena, Egypt
- Chemical Physics and NanoLund, Lund University, 22100, Lund, Sweden
| | - Ahmed Zaki Alhakemy
- Chemistry Department, Faculty of Science, Al-Azhar University, Assiut, 71542, Egypt
| | - Islam M A Mekhemer
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Ahmed Esmail A Aboubakr
- Sustainable Chemical Science and Technology, Taiwan International Graduate Program, Taipei, Taiwan
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu, 30010, Taiwan
- Institute of Chemistry, Academia Sinica, 128 Sec 2 Academia Rd., Nankang, Taipei, 11529, Taiwan
| | - Bo-Han Chen
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Amr Sabbah
- Center for Condensed Matter Sciences, National Taiwan University, Taipei, 10617, Taiwan
- Center of Atomic Initiative for New Materials, National Taiwan University, Taipei, 10617, Taiwan
| | - Kun-Han Lin
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Wen-Sheng Chiu
- Department of Chemical Engineering, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Sheng-Jie Lin
- Department of Chemical Engineering, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Che-Yi Chu
- Department of Chemical Engineering, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Chih-Hsuan Lu
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Shang-Da Yang
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Mohamed Gamal Mohamed
- Department of Materials and Optoelectronic Science, Center for Functional Polymers and Supramolecular Materials, National Sun Yat-Sen University, Kaohsiung 804, Kaohsiung, Taiwan
| | - Shiao-Wei Kuo
- Department of Materials and Optoelectronic Science, Center for Functional Polymers and Supramolecular Materials, National Sun Yat-Sen University, Kaohsiung 804, Kaohsiung, Taiwan
| | - Chen-Hsiung Hung
- Institute of Chemistry, Academia Sinica, 128 Sec 2 Academia Rd., Nankang, Taipei, 11529, Taiwan
| | - Li-Chyong Chen
- Center for Condensed Matter Sciences, National Taiwan University, Taipei, 10617, Taiwan
- Center of Atomic Initiative for New Materials, National Taiwan University, Taipei, 10617, Taiwan
- Department of Physics, National Taiwan University, Taipei, 10617, Taiwan
| | - Kuei-Hsien Chen
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
- Center for Condensed Matter Sciences, National Taiwan University, Taipei, 10617, Taiwan
| | - Ho-Hsiu Chou
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, 300044, Taiwan.
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Pensado A, Chiu WS, Cordery SF, Rantou E, Bunge AL, Delgado-Charro MB, Guy RH. Stratum Corneum Sampling to Assess Bioequivalence between Topical Acyclovir Products. Pharm Res 2019; 36:180. [PMID: 31728737 PMCID: PMC6856025 DOI: 10.1007/s11095-019-2707-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 09/20/2019] [Accepted: 09/20/2019] [Indexed: 11/01/2022]
Abstract
PURPOSE To examine the potential of stratum corneum (SC) sampling via tape-stripping in humans to assess bioequivalence of topical acyclovir drug products, and to explore the potential value of alternative metrics of local skin bioavailability calculable from SC sampling experiments. METHODS Three acyclovir creams were considered in two separate studies in which drug amounts in the SC after uptake and clearance periods were measured and used to assess bioequivalence. In each study, a "reference" formulation (evaluated twice) was compared to the "test" in 10 subjects. Each application site was replicated to achieve greater statistical power with fewer volunteers. RESULTS SC sampling revealed similarities and differences between products consistent with results from other surrogate bioequivalence measures, including dermal open-flow microperfusion experiments. Further analysis of the tape-stripping data permitted acyclovir flux into the viable skin to be deduced and drug concentration in that 'compartment' to be estimated. CONCLUSIONS Acyclovir quantities determined in the SC, following a single-time point uptake and clearance protocol, can be judiciously used both to objectively compare product performance in vivo and to assess delivery of the active into skin tissue below the barrier, thereby permitting local concentrations at or near to the site of action to be determined.
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Affiliation(s)
- A Pensado
- Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - W S Chiu
- Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - S F Cordery
- Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - E Rantou
- Office of Biostatistics, Office of Translational Sciences, Center for Drug Evaluation and Research, United States Food and Drug Administration, White Oak Campus, Silver Spring, MD, USA
| | - A L Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO, USA
| | - M B Delgado-Charro
- Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - R H Guy
- Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
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Cordery SF, Pensado A, Chiu WS, Shehab MZ, Bunge AL, Delgado-Charro MB, Guy RH. Topical bioavailability of diclofenac from locally-acting, dermatological formulations. Int J Pharm 2017; 529:55-64. [PMID: 28636892 PMCID: PMC5557682 DOI: 10.1016/j.ijpharm.2017.06.063] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [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: 05/07/2017] [Revised: 06/13/2017] [Accepted: 06/16/2017] [Indexed: 11/17/2022]
Abstract
Assessment of the bioavailability of topically applied drugs designed to act within or beneath the skin is a challenging objective. A number of different, but potentially complementary, techniques are under evaluation. The objective of this work was to evaluate in vitro skin penetration and stratum corneum tape-stripping in vivo as tools with which to measure topical diclofenac bioavailability from three approved and commercialized products (two gels and one solution). Drug uptake into, and its subsequent clearance from, the stratum corneum of human volunteers was used to estimate the input rate of diclofenac into the viable skin layers. This flux was compared to that measured across excised porcine skin in conventional diffusion cells. Both techniques clearly demonstrated (a) the superiority in terms of drug delivery from the solution, and (b) that the two gels performed similarly. There was qualitative and, importantly, quantitative agreement between the in vitro and in vivo measurements of drug flux into and beyond the viable skin. Evidence is therefore presented to support an in vivo - in vitro correlation between methods to assess topical drug bioavailability. The potential value of the stratum corneum tape-stripping technique to quantify drug delivery into (epi)dermal and subcutaneous tissue beneath the barrier is demonstrated.
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Affiliation(s)
- S F Cordery
- Department of Pharmacy & Pharmacology, University of Bath, Bath, UK
| | - A Pensado
- Department of Pharmacy & Pharmacology, University of Bath, Bath, UK
| | - W S Chiu
- Department of Pharmacy & Pharmacology, University of Bath, Bath, UK
| | - M Z Shehab
- Department of Pharmacy & Pharmacology, University of Bath, Bath, UK
| | - A L Bunge
- Chemical and Biological Engineering, Colorado School of Mines, Golden, CO, USA
| | | | - R H Guy
- Department of Pharmacy & Pharmacology, University of Bath, Bath, UK.
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Abstract
Sustained carrying could result in muscular fatigue of the upper limb. Ten male and ten female subjects were recruited for measurements of isometric arm strength before and during carrying a load for a period of 4 minutes. Two levels of load of carrying were tested for each of the male and female subjects. Exponential function based predictive equations for the isometric arm strength were established. The mean absolute deviations of these models in predicting the isometric arm strength were in the range of 3.24 to 17.34 N. Regression analyses between the subjective ratings of upper limb fatigue and force change index (FCI) for the carrying were also performed. The results indicated that the subjective rating of muscular fatigue may be estimated by multiplying the FCI with a constant. The FCI may, therefore, be adopted as an index to assess muscular fatigue for two-handed carrying tasks.
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Affiliation(s)
- Kai Way Li
- Department of Industrial Management, Chung Hua University, Hsin-Chu, Taiwan
| | - Wen-Sheng Chiu
- Ph.D Program of Technology Management, Chung Hua University, Hsin-Chu, Taiwan
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Wang CH, Chang CC, Liang YM, Shih CM, Chiu WS, Tseng P, Hung DL, Tzeng OJL, Muggleton NG, Juan CH. Open vs. closed skill sports and the modulation of inhibitory control. PLoS One 2013; 8:e55773. [PMID: 23418458 PMCID: PMC3572130 DOI: 10.1371/journal.pone.0055773] [Citation(s) in RCA: 134] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 01/04/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Inhibitory control, or the ability to suppress planned but inappropriate prepotent actions in the current environment, plays an important role in the control of human performance. Evidence from empirical studies utilizing a sport-specific design has shown that athletes have superior inhibitory control. However, less is known about whether this superiority might (1) still be seen in a general cognitive task without a sport-related context; (2) be modulated differentially by different sporting expertise (e.g., tennis versus swimming). METHODOLOGY/PRINCIPAL FINDINGS Here we compared inhibitory control across tennis players, swimmers and sedentary non-athletic controls using a stop-signal task without a sport-specific design. Our primary finding showed that tennis players had shorter stop-signal reaction times (SSRTs) when compared to swimmers and sedentary controls, whereas no difference was found between swimmers and sedentary controls. Importantly, this effect was further confirmed after considering potential confounding factors (e.g., BMI, training experience, estimated levels of physical activity and VO2max), indicative of better ability to inhibit unrequired responses in tennis players. CONCLUSIONS/SIGNIFICANCE This suggests that fundamental inhibitory control in athletes can benefit from open skill training. Sport with both physical and cognitive demands may provide a potential clinical intervention for those who have difficulties in inhibitory control.
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Affiliation(s)
- Chun-Hao Wang
- Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan
- Institute of Cognitive Neuroscience, National Central University, Jhongli, Taiwan
| | - Che-Chien Chang
- Office of Physical Education, National Central University, Jhongli, Taiwan
| | - Yen-Ming Liang
- Office of Physical Education, National Central University, Jhongli, Taiwan
| | - Chun-Ming Shih
- Institute of Cognitive Neuroscience, National Central University, Jhongli, Taiwan
- Graduate School of Human Sexuality, Shu-Te University, Kaoshiung, Taiwan
| | - Wen-Sheng Chiu
- Office of Physical Education, National Central University, Jhongli, Taiwan
| | - Philip Tseng
- Institute of Cognitive Neuroscience, National Central University, Jhongli, Taiwan
| | - Daisy L. Hung
- Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan
- Institute of Cognitive Neuroscience, National Central University, Jhongli, Taiwan
- Laboratories for Cognitive Neuroscience, National Yang-Ming University, Taipei, Taiwan
| | - Ovid J. L. Tzeng
- Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan
- Institute of Cognitive Neuroscience, National Central University, Jhongli, Taiwan
- Laboratories for Cognitive Neuroscience, National Yang-Ming University, Taipei, Taiwan
- Institute of Linguistics, Academia Sinica, Taipei, Taiwan
| | - Neil G. Muggleton
- Institute of Cognitive Neuroscience, National Central University, Jhongli, Taiwan
- Laboratories for Cognitive Neuroscience, National Yang-Ming University, Taipei, Taiwan
- Institute of Cognitive Neuroscience, University College of London, London, United Kingdom
| | - Chi-Hung Juan
- Institute of Cognitive Neuroscience, National Central University, Jhongli, Taiwan
- Laboratories for Cognitive Neuroscience, National Yang-Ming University, Taipei, Taiwan
- * E-mail:
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O'Brien KD, Pineda C, Chiu WS, Bowen R, Deeg MA. Glycosylphosphatidylinositol-specific phospholipase D is expressed by macrophages in human atherosclerosis and colocalizes with oxidation epitopes. Circulation 1999; 99:2876-82. [PMID: 10359731 DOI: 10.1161/01.cir.99.22.2876] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) may play an important role in inflammation, because it can hydrolyze the GPI anchors of several inflammatory membrane proteins (eg, CD106, CD55, and CD59) and its hydrolytic products upregulate macrophage cytokine expression (eg, interleukin-1 and tumor necrosis factor-alpha). Because of its potential regulatory role in inflammatory reactions, we hypothesized that GPI-PLD might be expressed in atherosclerosis. METHODS AND RESULTS Immunohistochemistry using human GPI-PLD-specific rabbit polyclonal antiserum was performed on a total of 83 nonatherosclerotic and atherosclerotic human coronary arteries from 23 patients. Macrophages, smooth muscle cells, apoA-I, and oxidation epitopes also were identified immunohistochemically. Cell-associated GPI-PLD was detected in 95% of atherosclerotic segments, primarily on a subset of macrophages. Extracellular GPI-PLD was present in only 30% of atherosclerotic segments and localized to regions with extracellular apoA-I. In contrast, GPI-PLD was not detected in nonatherosclerotic segments. Expression of GPI-PLD mRNA by human macrophages was confirmed in vitro by reverse transcription/polymerase chain reaction. Further studies demonstrated that GPI-PLD-positive plaque macrophages contained oxidation epitopes, suggesting a link between oxidant stress and GPI-PLD expression. This possibility was supported by studies in which exposure of a macrophage cell line to H2O2 led to a 50+/-3% increase in steady-state GPI-PLD mRNA levels. CONCLUSIONS Collectively, these results suggest that oxidative processes may regulate GPI-PLD expression and suggest a role for GPI-PLD in inflammation and in the pathogenesis of atherosclerosis.
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Affiliation(s)
- K D O'Brien
- Division of Cardiology, Department of Medicine, University of Washington, Seattle, USA.
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Chiu WS, Nguyen D. Pacemaker lead extraction in pacemaker endocarditis with lead vegetation: usefulness of transesophageal echocardiography. Can J Cardiol 1998; 14:87-9. [PMID: 9487279] [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: 02/06/2023] Open
Abstract
While pacemaker endocarditis is rare, it is a complication that mandates removal of the permanent pacemaker system, including the electrode lead. Many modes of lead removal have been used. The choice of method is determined largely by lead type and chronicity (i.e., risk of substantial adhesions, hence, lead tip mobility). Patient selection has been based on general preoperative risk assessment. It is proposed that the presence of lead vegetation be considered in the decision-making process. Vegetation can be diagnosed by preoperative echocardiography, especially with clinical suspicion of embolism. Transesophageal echocardiography appears to be particularly sensitive. If vegetation is detected, open heart surgery should be strongly considered for lead removal as opposed to dilator sheath counter traction. The latter method risks shearing off the vegetation, which may result in septic--even massive--pulmonary embolus.
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Affiliation(s)
- W S Chiu
- Department of Internal Medicine, Montreal General Hospital/McGill University, Quebec
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D'Arcy TJ, Hughes SW, Chiu WS, Clark T, Milner AD, Saunders J, Maxwell D. Estimation of fetal lung volume using enhanced 3-dimensional ultrasound: a new method and first result. Br J Obstet Gynaecol 1996; 103:1015-20. [PMID: 8863701 DOI: 10.1111/j.1471-0528.1996.tb09553.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To measure fetal lung volume using a computer based, enhanced, 3-dimensional ultrasound imaging system. DESIGN An observational study. SETTING The Fetal Medicine Unit at Guys Hospital, London. PARTICIPANTS Twenty healthy women with a singleton pregnancy between 24 and 36 weeks of gestation were scanned on one occasion during pregnancy using an ultrasound based 3-dimensional imaging system. All delivered at term with weights above the 10th centile for gestation. RESULTS Total lung volume increased exponentially with gestational age. Right lung volume measured consistently greater than left lung volume. CONCLUSIONS The use of this new enhanced 3-dimensional imaging system allows for estimations of fetal lung volume. Preliminary data confirm that fetal lung volume, measured by a computerised 3-dimensional ultrasound imaging system increased exponentially with gestational age. The use of this system has obvious application in the further study of lung growth in utero and possible clinical application in disease states where fetal lung growth may be impaired.
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Affiliation(s)
- T J D'Arcy
- Department of Obstetrics and Gynaecology, Guys and St. Thomas' Hospital Trust, London, UK
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Hughes SW, D'Arcy TJ, Maxwell DJ, Saunders JE, Ruff CF, Chiu WS, Sheppard RJ. Application of a new discreet form of Gauss' theorem for measuring volume. Phys Med Biol 1996; 41:1809-21. [PMID: 8884913 DOI: 10.1088/0031-9155/41/9/016] [Citation(s) in RCA: 26] [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: 02/02/2023]
Abstract
Volume measurements are useful in many branches of science and medicine. They are usually accomplished by acquiring a sequence of cross sectional images through the object using an appropriate scanning modality, for example x-ray computed tomography (CT), magnetic resonance (MR) or ultrasound (US). In the cases of CT and MR, a dividing cubes algorithm can be used to describe the surface as a triangle mesh. However, such algorithms are not suitable for US data, especially when the image sequence is multiplanar (as it usually is). This problem may be overcome by manually tracing regions of interest (ROIs) on the registered multiplanar images and connecting the points into a triangular mesh. In this paper we describe and evaluate a new discreet form of Gauss' theorem which enables the calculation of the volume of any enclosed surface described by a triangular mesh. The volume is calculated by summing the vector product of the centroid, area and normal of each surface triangle. The algorithm was tested on computer-generated objects, US-scanned balloons, livers and kidneys and CT-scanned clay rocks. The results, expressed as the mean percentage difference +/- one standard deviation were 1.2 +/- 2.3, 5.5 +/- 4.7, 3.0 +/- 3.2 and -1.2 +/- 3.2% for balloons, livers, kidneys and rocks respectively. The results compare favourably with other volume estimation methods such as planimetry and tetrahedral decomposition.
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Affiliation(s)
- S W Hughes
- Department of Medical Physics, Guy's and St Thomas' Hospital, London, UK
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Chiu WS, Shadle CH, Carter JN. Quantitative measures of the palate using enhanced electropalatography. Eur J Disord Commun 1995; 30:149-160. [PMID: 7492846 DOI: 10.3109/13682829509082526] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Electropalatography (EPG) is a useful tool for investigating tongue dynamics in experimental phonetic research and speech therapy. However, data provided by EPG are a two-dimensional representation in which all absolute positional information is lost. This paper presents an enhanced EPG (eEPG) system which uses digitised palate shape data to display the tongue-palate contact pattern in three dimensions. The palate shapes are obtained using a colour-encoded structured light three-dimensional digitisation system. The three-dimensional palate shape is displayed on a Silicon Graphics workstation as a surface made up of polygons represented by a quadrilateral mesh. EPG contact patterns are superimposed on to the three-dimensional palate shape by displaying the relevant polygons in a different colour. By using this system, differences in shape between individual palates, apparent on visual inspection of the actual palates, are also apparent in the image on screen. Further, methods have been devised for computing absolute distances along paths lying on the palate surface. Combining this with calibrated palate shape data allows accurate measurements to be made between contact locations on the palate. These have been validated with manual measurements. In addition, vocal tract areas in the oral cavity have been estimated by using the absolute measurements on the palate for a given contact pattern, and assuming a flat tongue profile in the uncontacted area.
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Affiliation(s)
- W S Chiu
- Department of Electronics and Computer Science, University of Southampton, UK
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Abstract
We report nine cases of neuropathy occurring after renal transplantation, seven of them femoral and two lateral femoral cutaneous. The average time of onset of symptoms is 2.2 days after surgery. Quadriceps weakness, hypoesthesia, and abnormal results of EMG and nerve conduction studies are common and occur on the same side as the operation. The symptoms usually resolve within weeks, but motor and sensory changes can persist. The lesion is thought to be secondary to compression caused by a hematoma at the operative site.
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Abstract
A syndrome of retroperitoneal hemorrhage during anticoagulant therapy associated with nerve involvement in femoral nerve or lumbar plexus is described. Twenty-one cases were collected from the English-language literature, and five new cases were added for review and analysis. In these 26 cases spontaneous hemorrhage occurred under iliopsoas fascia in the retroperitoneal space. The clinical picture, involved nerves, laboratory findings of coagulation studies, anemia, and the outcome of these cases are summarized and discussed. Retroperitoneal space may contain a large quantity of internal hemorrhage. Irreversible damage of lumbar plexus or femoral nerve may result from entrapment of nerves in the hematoma. Laboratory coagulation studies may guide effective administration of anticoagulant therapy and minimize hemorrhagic complication, but they will not eliminate the risk of hemorrhage completely.
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