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1.
BMC Oral Health ; 23(1): 1002, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097978

RESUMO

BACKGROUND: The study on oral health-related quality of life (OHRQoL) of disabled patients is rare but critical for welfare of patients. The aim of this study was to examine the effect of fixed implants in edentulous areas on OHRQoL in Korean disabled patients. METHODS: The OHRQoL of 63 disabled individuals was evaluated using the Oral Health Impact Profile (OHIP)-14 questionnaires and studied by potential affecting variables such as age, sex, disability severity, and time of disability acquisition. Wilcoxon-signed rank tests were used to examine the OHIP-14 scores for those who had pre/post-fixed implants. Multiple linear regression analysis was used to examine the relationships between factors and OHIP-14 scores before and after implants. A partial correlation analysis was also performed to determine which variables influenced OHIP-14 scores before and after treatment. The Mann-Whitney test was employed for sex and time of disability acquisition analysis (α = 0.05). RESULTS: Significant improvement was found in OHIP-14 post-implant treatment scores (P < .001). After implant treatment, the severity of disability produced significantly different results (P = .009). Pearson's correlation coefficient between severity of disability and pre/post-implant OHIP-14 scores was 0.265 (P = .030). After controlling for severity of disability, the results showed older patients had lower OHIP-14 scores (P = .032). No differences were found for sex or time of disability acquisition (congenital vs. acquired). CONCLUSIONS: Fixed implant treatment improved OHRQoL for disabled patients, and the severity of disability was positively correlated with improvement of OHRQoL. For patients with a similar level of disability, the OHRQoL decreased with age.


Assuntos
Implantes Dentários , Qualidade de Vida , Humanos , Estudos Retrospectivos , Saúde Bucal , Inquéritos e Questionários
2.
Korean J Radiol ; 24(8): 807-820, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37500581

RESUMO

OBJECTIVE: To assess whether computed tomography (CT) conversion across different scan parameters and manufacturers using a routable generative adversarial network (RouteGAN) can improve the accuracy and variability in quantifying interstitial lung disease (ILD) using a deep learning-based automated software. MATERIALS AND METHODS: This study included patients with ILD who underwent thin-section CT. Unmatched CT images obtained using scanners from four manufacturers (vendors A-D), standard- or low-radiation doses, and sharp or medium kernels were classified into groups 1-7 according to acquisition conditions. CT images in groups 2-7 were converted into the target CT style (Group 1: vendor A, standard dose, and sharp kernel) using a RouteGAN. ILD was quantified on original and converted CT images using a deep learning-based software (Aview, Coreline Soft). The accuracy of quantification was analyzed using the dice similarity coefficient (DSC) and pixel-wise overlap accuracy metrics against manual quantification by a radiologist. Five radiologists evaluated quantification accuracy using a 10-point visual scoring system. RESULTS: Three hundred and fifty CT slices from 150 patients (mean age: 67.6 ± 10.7 years; 56 females) were included. The overlap accuracies for quantifying total abnormalities in groups 2-7 improved after CT conversion (original vs. converted: 0.63 vs. 0.68 for DSC, 0.66 vs. 0.70 for pixel-wise recall, and 0.68 vs. 0.73 for pixel-wise precision; P < 0.002 for all). The DSCs of fibrosis score, honeycombing, and reticulation significantly increased after CT conversion (0.32 vs. 0.64, 0.19 vs. 0.47, and 0.23 vs. 0.54, P < 0.002 for all), whereas those of ground-glass opacity, consolidation, and emphysema did not change significantly or decreased slightly. The radiologists' scores were significantly higher (P < 0.001) and less variable on converted CT. CONCLUSION: CT conversion using a RouteGAN can improve the accuracy and variability of CT images obtained using different scan parameters and manufacturers in deep learning-based quantification of ILD.


Assuntos
Enfisema , Doenças Pulmonares Intersticiais , Enfisema Pulmonar , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Pulmão/diagnóstico por imagem
3.
Talanta ; 260: 124590, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37146455

RESUMO

Dopamine (DA) is a crucial neurotransmitter involved in the hormonal, nervous, and vascular systems being considered as an index to diagnose neurodegenerative diseases, including Parkinson's and Alzheimer's disease. Herein, we demonstrate the quantitative sensing of DA using the peak shift in surface-enhanced Raman scattering (SERS) of 4-mercaptophenylboronic acid (4-MPBA), resulting from the concentration of DA. To enable the signal enhancement of Raman scattering, Ag nanostructure was built with one-step gas-flow sputtering. 4-MPBA was then introduced using vapor-based deposition, acting as a reporter molecule for bonding with DA. The gradual peak-shift from 1075.6 cm-1 to 1084.7 cm-1 was observed with the increasing concentration of DA from 1 pM to 100nM. The numerical simulation revealed that DA bonding induced a constrained vibrational mode corresponding to 1084.7 cm-1 instead of a C-S-coupled C-ring in-plane bending mode of 4-MPBA corresponding to 1075.6 cm-1. Proposed SERS sensors depicted reliable DA detection in human serum and good selectivity against other analytes, including glucose, creatinine, and uric acid.


Assuntos
Dopamina , Nanopartículas Metálicas , Humanos , Análise Espectral Raman/métodos , Nanopartículas Metálicas/química , Glucose
4.
Front Pharmacol ; 13: 1033341, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386230

RESUMO

Retinopathy of prematurity (ROP), a vascular disease characterized by abnormal vessel development in the retina, has become a primary cause of blindness in children around the world. ROP can be developed during two different phases: vessel loss and vessel proliferation. Once preterm infants with immature retinal vessel growth are exposed to high level of oxygen inside the incubator, vessel loss can occur. When infants are exposed to room air, they may experience the proliferation of vessels in the retina. Although multiple factors are reported to be involved in the pathogenesis of ROP, including vaso-endothelial growth factors (VEGFs) and hypoxia-inducible factors, the pathogenesis of ROP is not completely understood. Although laser therapy and pharmacologic agents, such as anti-VEGF agents, have been commonly used to treat ROP, the incidence of ROP is rapidly rising. Given that current therapies can be invasive and long-term effects are not fully known, the search for novel therapeutic targets with less destructive properties needs to be considered. Within the last decade, the field of noncoding RNA therapy has shown potential as next-generation therapy to treat diverse diseases. In this review, we introduce various noncoding RNAs regulating ROP and discuss their role as potential therapeutic targets in ROP.

5.
Materials (Basel) ; 15(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36295331

RESUMO

Using a thermal evaporator, various porous Cu films were deposited according to the deposition pressure. CuO films were formed by post heat treatment in the air. Changes in morphological and structural characteristics of films were analyzed using field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). Relative density and porosity were quantitatively calculated. CuO films with various pores ranging from 39.4 to 95.2% were successfully manufactured and were applied as gas sensors for H2S detection on interdigitated electrode (IDE) substrate. Resistance change was monitored at 325 °C and an increase in porosity of the film improved the sensor performance. The CuO-10 gas sensor with a high porosity of 95.2% showed a relatively high response (2.7) and a fast recovery time (514 s) for H2S 1.5 ppm. It is confirmed that the porosity of the CuO detection layer had a significant effect on response and recovery time.

6.
Phys Med Biol ; 67(21)2022 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-36162401

RESUMO

Objective.To unify the style of computed tomography (CT) images from multiple sources, we propose a novel multi-domain image translation network to convert CT images from different scan parameters and manufacturers by simply changing a routing vector.Approach.Unlike the existing multi-domain translation techniques, our method is based on a shared encoder and a routable decoder architecture to maximize the expressivity and conditioning power of the network.Main results.Experimental results show that the proposed CT image conversion can minimize the variation of image characteristics caused by imaging parameters, reconstruction algorithms, and hardware designs. Quantitative results and clinical evaluation from radiologists also show that our method can provide accurate translation results.Significance.Quantitative evaluation of CT images from multi-site or longitudinal studies has been a difficult problem due to the image variation depending on CT scan parameters and manufacturers. The proposed method can be utilized to address this for the quantitative analysis of multi-domain CT images.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos
7.
ACS Appl Mater Interfaces ; 14(36): 41629-41639, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36043945

RESUMO

For surface-enhanced Raman spectroscopy (SERS) sensing of small molecules in the presence of living cells, biofouling and blocking of plasmonic centers are key challenges. Here, we have developed a mesoporous Au (AuM) film coated with a Ag nanoparticles (NPs) as a plasmonic sensor (AuM@Ag) to analyze aromatic thiols, which is an example of a small molecule, in the presence of a living cell strain (e.g., MDA-MB-231) as a model living system. The resulting AuM@Ag provides 0.1 nM sensitivity and high reproducibility for thiols sensing. Simultaneously, the AuM@Ag film filters large biomolecules, preventing Raman signals from overlapping produced by large biomolecules. After analysis, the AuM@Ag film undergoes recycling by the full dissolution of the Ag-thiol layer and removal of thiols from AuM. Furthermore, fresh AgNPs are formed for further SERS analysis, which circumvents the Ag oxidation issue. The ease of the AgNPs deposition allows up to 12 cycles of on-demand recycling and sensing even after utilization as a sensor in multicomponent media without enhancement and sensitivity loss. The reported mesoporous film with surface filtering ability and prominent recycling procedure promises to offer a new strategy for the detection of various small molecules in the presence of living cells.


Assuntos
Nanopartículas Metálicas , Prata , Ouro/química , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Prata/química , Análise Espectral Raman/métodos , Compostos de Sulfidrila/química
8.
Clin Exp Emerg Med ; 9(3): 238-245, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36039600

RESUMO

OBJECTIVE: Since onsite education is difficult due to the COVID-19 pandemic, official development assistance (ODA) projects have implemented online training of trainers (ToT) for emergency medical experts and staff. This study aims to share and discuss the ToT experience and its results in Uzbekistan. METHODS: We trained emergency medical advanced course instructors through online ToT among emergency medical service experts in Uzbekistan as a part of an ODA project. After the ToT, instructors were selected based on written tests, video monitoring of practice, and simulation performance. They operated the emergency medical course including lectures, practices, and simulations for 5 days. We tested the trainees through written tests before and after the course. They were surveyed regarding the course contents, its relevance, and their satisfaction with the course. RESULTS: Six instructors were selected after the online ToT program. They educated 68 emergency medical workers through the three training courses. The total score of the pretest was 129.2±34.8, and the posttest score was 170.8±31.2, which was significantly higher (P<0.05). The satisfaction calculated by adding the values of survey items for this curriculum was 28.0 (interquartile range, 26.0-30.0), and there was no statistical difference regarding trainee satisfaction between the three courses (P=0.148). CONCLUSION: Instructors trained by online ToT programs could provide an in-person emergency medical advanced course.

9.
Mikrochim Acta ; 189(8): 288, 2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35879508

RESUMO

A controllable method for fabricating flexible surface-enhanced Raman scattering (SERS) substrates is demonstrated by depositing silver onto a flexible nanopillar array film. The flexible nanopillar array film was cost-effectively prepared by replicating an anodic aluminum oxide (AAO) template with UV-curable polyurethane acrylate (PUA) over a large area. Then, the deposition of silver was done by an Ar-assisted thermal evaporation. In the deposition process, the partial pressure of Ar was optimized because it has a significant influence on the SERS intensity through the microstructural changes of silver deposited on PUA nanopillars. In addition, the increase in the nanopillar diameter and height enhanced the SERS intensity obtained at 785-nm excitation because of the increased number of hot spots. However, the agglomeration of Ag-deposited nanopillars, which is caused by high aspect ratios, negatively affected the SERS performance in terms of intensity and standard deviation. The optimized Ag-deposited nanopillar array film with nanopillar diameters and heights of 80 nm and 200 nm exhibited excellent SERS sensitivity and signal reproducibility with stable mechanical flexibility. For application in food and biomedical analysis, it was used for detecting saccharin and peptide and showed a good linear relationship between the SERS intensity and concentration. These findings demonstrate the suitability of our method for the controllable fabrication and optimization of flexible SERS substrates with high sensitivity and reproducibility.


Assuntos
Prata , Análise Espectral Raman , Acrilatos , Poliuretanos , Reprodutibilidade dos Testes , Prata/química , Análise Espectral Raman/métodos
10.
Clin Exp Emerg Med ; 9(2): 114-119, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35843611

RESUMO

OBJECTIVE: We aimed to investigate the characteristics of frequent emergency department (ED) users in Korea. METHODS: We analyzed the Korea Health Panel Study data of a sampled population from the 2005 Population Census of Korea data, and adults (age ≥18 years) who visited the ED at least once a year between 2014 and 2017 were included in the study. People who visited three or more times a year were classified as frequent users. We compared demographic, socioeconomic, and health-related factors between nonfrequent and frequent users. We used a multivariable logistic regression analysis to determine factors related to frequent ED visits. We also compared the characteristics of ED use in both nonfrequent and frequent users. RESULTS: A total of 5,090 panels were included, comprising 6,853 visits. Frequent users were 333 (6.5% of all panels), and their ED visits were 1,364 (19.9% of all ED visits). In the multivariable regression analysis, medical aid coverage (adjusted odds ratio [aOR] of the National Health Service coverage, 0.55; 95% confidence interval [CI], 0.40-0.75), unemployment (aOR of employment, 0.72; 95% CI, 0.56-0.91), prior ward admission in a year (aOR, 2.14; 95% CI, 1.67-2.75), and frequent outpatient department use (aOR, 1.72; 95% CI, 1.35-2.20) were associated with frequent use. Moreover, frequent users visited the ED of public hospitals more often than than nonfrequent users (19.2% vs. 9.8%). Medical problems rather than injury/poisoning were the more common reasons for visiting the ED (84.5% vs. 71.2%). CONCLUSION: We found that frequent ED users were likely to be those with socioeconomic disadvantage or with high demand for medical service. Based on this study, further studies on interventions to reduce frequent ED use are required for better ED services.

11.
Small ; 18(25): e2107182, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35570326

RESUMO

This article reviews recent fabrication methods for surface-enhanced Raman spectroscopy (SERS) substrates with a focus on advanced nanoarchitecture based on noble metals with special nanospaces (round tips, gaps, and porous spaces), nanolayered 2D materials, including hybridization with metallic nanostructures (NSs), and the contemporary repertoire of nanoarchitecturing with organic molecules. The use of SERS for multidisciplinary applications has been extensively investigated because the considerably enhanced signal intensity enables the detection of a very small number of molecules with molecular fingerprints. Nanoarchitecture strategies for the design of new NSs play a vital role in developing SERS substrates. In this review, recent achievements with respect to the special morphology of metallic NSs are discussed, and future directions are outlined for the development of available NSs with reproducible preparation and well-controlled nanoarchitecture. Nanolayered 2D materials are proposed for SERS applications as an alternative to the noble metals. The modern solutions to existing limitations for their applications are described together with the state-of-the-art in bio/environmental SERS sensing using 2D materials-based composites. To complement the existing toolbox of plasmonic inorganic NSs, hybridization with organic molecules is proposed to improve the stability of NSs and selectivity of SERS sensing by hybridizing with small or large organic molecules.


Assuntos
Nanoestruturas , Análise Espectral Raman , Nanoestruturas/química , Análise Espectral Raman/métodos
12.
Biosens Bioelectron ; 180: 113109, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33677356

RESUMO

Here, we present a new family of hierarchical porous hybrid materials as an innovative tool for ultrasensitive and selective sensing of enantiomeric drugs in complex biosamples via chiral surface-enhanced Raman spectroscopy (SERS). Hierarchical porous hybrid films were prepared by the combination of mesoporous plasmonic Au films and microporous homochiral metal-organic frameworks (HMOFs). The proposed hierarchical porous substrates enable extremely low limit of detection values (10-12 M) for pseudoephedrine in undiluted blood plasma due to dual enhancement mechanisms (physical enhancement by the mesoporous Au nanostructures and chemical enhancement by HMOF), chemical recognition by HMOF, and a discriminant function for bio-samples containing large biomolecules, such as blood components. We demonstrate the effect of each component (mesoporous Au and microporous AlaZnCl (HMOF)) on the analytical performance for sensing. The growth of AlaZnCl leads to an increase in the SERS signal (by around 17 times), while the use of mesoporous Au leads to an increase in the signal (by up to 40%). In the presence of a complex biomatrix (blood serum or plasma), the hybrid hierarchical porous substrate provides control over the transport of the molecules inside the pores and prevents blood protein infiltration, provoking competition with existing plasmonic materials at the limit of detection and enantioselectivity in the presence of a multicomponent biomatrix.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Ouro , Plasma , Pseudoefedrina , Estereoisomerismo
13.
Sensors (Basel) ; 21(2)2021 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-33477265

RESUMO

Metal-oxide sensors, detect gas through the reaction of surface oxygen molecules with target gases, are promising for the detection of toxic pollutant gases, combustible gases, and organic vapors; however, their sensitivity, selectivity, and long-term stability limit practical applications. Porous structure for increasing surface area, adding catalyst, and altering the operation temperature are proposed for enhancing the sensitivity and selectivity. Although humidity can significantly affect the property and stability of the sensors, studies focusing on the long-term stability of gas sensors are scarce. To reduce the effects of humidity, 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane (PFOTS) was coated on a porous SnO2 film. The interconnected SnO2 nanowires improved the high surface area, and the PFOTS coating provided superhydrophobicity at water contact angle of 159°and perfect water vapor repellency inside E-SEM. The superhydrophobic porous morphology was maintained under relative humidity of 99% and operating temperature of 300 °C. The CO gas sensing of 5, 20, and 50 ppm were obtained with linearity at various humidity. Flame detection was also achieved with practical high humidity conditions. These results suggest the simple way for reliable sensing of nanostructured metal-oxide gas sensors with high sensitivity and long-term stability even in highly humid environments.

14.
Biosensors (Basel) ; 10(9)2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32872302

RESUMO

Lactic acid plays an important role as a biochemical indicator for sports medicine and clinical diagnosis. The detection of lactic acid in sweat is a promising technique without any intrusive inconvenience or risk of infection. In this study, we present a selective nonenzymatic amperometric detection method for lactic acid in human sweat utilizing a multi-wall carbon nanotube (MWCNT)-polypyrrole core-shell nanowire. Because polypyrrole is a p-type conducting polymer, onto which anions are exclusively doped, leading to charge transfer, it offers selective detection for lactate anions at a specific potential, while being inert to the neutral and cationic species contained in human sweat. A chronoamperometric study reveals good sensing performance for lactic acid with a high sensitivity of 2.9 µA mM-1 cm-2 and detection limit of 51 µM. Furthermore, the MWCNT-polypyrrole nanowire exhibits excellent selectivity for lactic acid over interfering species, such as sodium chloride, glucose, urea, and riboflavin, which coexist with lactic acid in sweat. Finally, a nonenzymatic amperometric sensor for the selective detection of lactic acid in human sweat is demonstrated on commercial flexible electrodes. The results demonstrate the potential applications of the MWCNT-polypyrrole core-shell nanowire as a nonenzymatic amperometric lactate sensor.


Assuntos
Técnicas Biossensoriais , Ácido Láctico/análise , Suor/química , Técnicas Eletroquímicas , Humanos , Nanotubos de Carbono , Nanofios
15.
Nat Protoc ; 15(9): 2980-3008, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32839575

RESUMO

High-surface-area mesoporous materials expose abundant functional sites for improved performance in applications such as gas storage/separation, catalysis, and sensing. Recently, soft templates composed of amphiphilic surfactants and block copolymers have been used to introduce mesoporosity in various materials, including metals, metal oxides and carbonaceous compounds. In particular, mesoporous metals are attractive in electrocatalysis because their porous networks expose numerous unsaturated atoms on high-index facets that are highly active in catalysis. In this protocol, we describe how to create mesoporous metal films composed of gold, palladium, or platinum using block copolymer micelle templates. The amphiphilic block copolymer micelles are the sacrificial templates and generate uniform structures with tunable pore sizes in electrodeposited metal films. The procedure describes the electrodeposition in detail, including parameters such as micelle diameters, deposition potentials, and deposition times to ensure reproducibility. The micelle diameters can be controlled by swelling the micelles with different solvent mixtures or by using block copolymer micelles with different molecular weights. The deposition potentials and deposition times allow further control of the mesoporous structure and its thickness, respectively. Procedures for example applications are included: glucose oxidation, ethanol oxidation and methanol oxidation reactions. The synthetic methods for preparation of mesoporous metal films will take ~4 h; the subsequent electrochemical tests will take ~5 h for glucose sensing and ~3 h for alcohol oxidation reaction.


Assuntos
Ouro/química , Paládio/química , Platina/química , Álcoois/química , Catálise , Técnicas de Química Sintética , Eletroquímica , Interações Hidrofóbicas e Hidrofílicas , Micelas , Modelos Moleculares , Conformação Molecular , Oxirredução , Polímeros/química
16.
Open Access Emerg Med ; 12: 19-26, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104110

RESUMO

INTRODUCTION: There are several medical elective programs for low-income countries especially in medically vulnerable places. The Hospital Central de Quelimane (HCQ) is a regional hospital in Quelimane, capital city of the province of Zambezia in Mozambique. The HCQ serves as a regional base hospital for urgent and severe patients. METHODS: Four emergency medicine (EM) residents participated in our 2017-2018 rotational program for HCQ, to share medical knowledge with the local medical doctors and support the demands of medical equipment skills and educational programs. We determined the current capabilities of HCQ and designed a rotational program in accordance with the demands in the following areas: resuscitation, trauma, critical care, and radiology. We also introduced continuous education programs and administrative methods for future development of education. RESULTS: Throughout the four rotations of our EM residents, we conducted daily education and several practical lessons based on the demands of the local doctors and equipment operation. The educational program was administered by an educational administrator who was responsible for updating the medical and technical knowledge of doctors. With our programs, the doctors of HCQ were able to perform resuscitation and critical protocols, including manipulating equipment such as mechanical ventilator and defibrillator. CONCLUSION: The rotation program by the four residents was successful, in terms of sharing medical knowledge and equipment management, and filling gaps identified in the operation of a modern hospital.

17.
Molecules ; 25(4)2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32059446

RESUMO

An amorphous Si (a-Si) solar cell with a back reflector composed of zinc oxide (ZnO) and silver (Ag) is potentially the most plausible and flexible solar cell if a graphite sheet is used as the substrate. Graphite supplies lightness, conductivity and flexibility to devices. When a graphite sheet is used as the substrate, carbon can diffuse into the Ag layer in the subsequent p-i-n process at 200-400 °C. To prevent this, we added an oxide layer as a carbon diffusion barrier between the carbon substrate and the back reflector. For the carbon diffusion barrier, silicon oxide (SiO2) or tin oxide (SnOx) was used. We evaluated the thermal stability of the back reflector of a carbon substrate using secondary-ion mass spectrometry (SIMS) to analyze the carbon diffusion barrier material. We confirmed the deposition characteristics, reflectance and prevention of carbon diffusion with and without the barrier. Finally, the structures were incorporated into the solar cell and their performances compared. The results showed that the back reflectors that were connected to a carbon diffusion barrier presented better performance, and the reflector with an SnOx layer presented the best performance.


Assuntos
Carbono/química , Fontes de Energia Elétrica , Grafite/química , Energia Solar , Difusão , Condutividade Elétrica , Óxidos , Dióxido de Silício/química , Prata/química , Luz Solar , Óxido de Zinco/química
18.
Data Brief ; 28: 104897, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31872012

RESUMO

Hydrogen-air proton exchange membrane fuel cells (PEMFC) have been drawn considerable attention as one of clean energy sources for transportation applications. To achieve the long lifetime of PEMFC for the transportation application, it is required to reduce the loss of electrochemical surface area which is known to result from dissolution of Pt nanoparticles and the size change of nanoparticle. Herein, we decorated Au on commercial Pt/C catalyst with various ratio of Au: Pt in a range of 2 to 0.33: 1 using a chemical reduction method with trisodium citrate. X-ray Diffraction (XRD) result clearly shows that the Au are well deposited on the surface of Pt/C catalysts. The electrochemical surface areas of catalyst are assessed as a function of Au concentration potential cycling in accelerated degradation tests. Furthermore, the oxygen reduction reaction (ORR) activity of Au-Pt/C is also estimated in comparison with that of commercial Pt/C using a single cell operation. X-ray photoelectron spectroscopy analysis shows that Au incorporation on Pt/C changes electron density of Pt surface and, consequently more reductive because of difference in work function between Au and Pt. Finally, we provide a series of dataset on the effect of Au on the surface of Pt/C catalyst to stabilize the electrochemical surface area.

19.
West J Emerg Med ; 20(6): 903-909, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31738717

RESUMO

INTRODUCTION: Low- and middle-income countries (LMICs) have a large percentage of global mortality and morbidity rates from non-communicable diseases, including trauma. The establishment and development of emergency care systems is crucial for addressing this problem. Defining gaps in the resources and capacity to provide emergency healthcare in LMICs is essential for proper design and operation of ECS (emergency care services) reinforcement programs. Myanmar has particular challenges with road access for providing timely emergency medical care, and a shortage of trained health workers. To examine the ECS capacity in Myanmar, we used the Emergency Care Assessment Tool (ECAT), which features newly developed tools for assessing sentinel conditions and signal functions (key interventions to address morbidity and mortality) in emergency care facilities. METHODS: ECAT is composed of six emergent sentinel conditions and corresponding signal functions. We surveyed a total of nine hospitals in five states in Myanmar. A constructed survey sheet was delivered by e-mail, and follow-up interviews were conducted via messenger to clarify ambiguous answers. RESULTS: We categorized the nine participating institutions according to predefined criteria: four basic-level hospitals; four intermediate-level; and one advanced-level hospital. All basic hospitals were weak in trauma care, and two of 12 signal functions were unavailable. Half of the intermediate hospitals showed weakness in trauma care, as well as critical care such as shock management. Only half had a separate triage area for patients. In contrast, all signal functions and resources listed in ECAT were available in the advanced-level hospital. CONCLUSION: Basic-level facilities in Myanmar were shown to be suboptimal in trauma management, with critical care also inadequate in intermediate facilities. To reinforce signal functions in Myanmar health facilities, stakeholders should consider expanding critical functions in selected lower-level health facilities. A larger scale survey would provide more comprehensive data to improve emergency care in Myanmar.


Assuntos
Atenção à Saúde/estatística & dados numéricos , Serviços Médicos de Emergência/normas , Serviço Hospitalar de Emergência , Hospitais/normas , Estudos Transversais , Serviços Médicos de Emergência/estatística & dados numéricos , Serviço Hospitalar de Emergência/normas , Necessidades e Demandas de Serviços de Saúde , Hospitais/estatística & dados numéricos , Humanos , Mianmar , Indicadores de Qualidade em Assistência à Saúde
20.
Clin Exp Emerg Med ; 6(4): 356-361, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31910508

RESUMO

OBJECTIVE: Smart glasses can provide sonographers with real-time ultrasound images. In the present study, we aimed to evaluate the utility of smart-glasses for ultrasound-guided peripheral venous access. METHODS: In this randomized, crossover-design, simulation study, 12 participants were recruited from the emergency department residents at a university hospital. Each participant attempted ultrasound-guided peripheral venous access on a pediatric phantom at intervals of 5 days with (glasses group) or without (non-glasses group) the use of smart glasses. In the glasses group, participants confirmed the ultrasound image through the lens of the smart glasses. In the non-glasses group, participants confirmed the ultrasound image through the display viewer located next to the phantom. Procedure time was regarded as the primary outcome, while secondary outcomes included the number of head movements for the participant, number of skin punctures, number of needle redirections, and subjective difficulty. RESULTS: No significant differences in procedural time were observed between the groups (non-glasses group: median time, 15.5 seconds; interquartile range [IQR], 10.3 to 27.3 seconds; glasses group: median time, 19.0 seconds; IQR, 14.3 to 39.3 seconds; P=0.58). The number of head movements was lower in the glasses group than in the non-glasses group (glasses group: median, 0; IQR, 0 to 0; non-glasses group: median, 4; IQR, 3 to 5; P<0.01). No significant differences in the number of skin punctures or needle restrictions were observed between the groups. CONCLUSION: Our results indicate that smart-glasses may aid in ensuring ultrasound-guided peripheral venous access by reducing head movements.

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