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1.
Int Ophthalmol ; 44(1): 304, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954136

RESUMO

PURPOSE: Our study aims to evaluate the surgical outcomes and clinical features of retinal detachment (RD) cases treated with segmental scleral buckling (SB), elucidating the role of segmental SB as a vital option in specific situations during the current era. METHODS: We retrospectively reviewed 128 eyes with primary rhegmatogenous RD that underwent segmental scleral buckling between November 2008 and December 2020. Clinical features and success rates were recorded and analyzed. RESULTS: A total of 128 eyes were included. The patient's ages ranged from 12 to 72 years, with a median age of 45. Most of the eyes were phakic (97%). Regarding the type of break, 47% were holes, and flap tears were found in 68 cases (53%). The break locations were superior-temporal (54%), inferior-temporal (31%), superior-nasal (9.5%), and inferior-nasal (5.5%). The length of the SB applied ranged from 3.5 to 8.0 clock hours, with a median of 6.0. Primary success was achieved in 121 eyes, and recurrence occurred in 7 eyes. All recurrent RD cases reattached after undergoing secondary VT. The causes of failure included 2 break reopens, 1 missed break, and 4 eyes with proliferative vitreoretinopathy. The single-surgery anatomic success (SSAS) rate for segmental SB was 94.5%. The final success rate was 100%. CONCLUSIONS: For phakic, low complexity retinal detachment in our study, segmental scleral buckling emerges as a surgical option with a high primary success rate and a lower incidence of complications.


Assuntos
Descolamento Retiniano , Recurvamento da Esclera , Acuidade Visual , Humanos , Recurvamento da Esclera/métodos , Descolamento Retiniano/cirurgia , Descolamento Retiniano/diagnóstico , Estudos Retrospectivos , Masculino , Feminino , Adulto , Criança , Adolescente , Pessoa de Meia-Idade , Adulto Jovem , Idoso , Seguimentos , Resultado do Tratamento
2.
J Am Chem Soc ; 146(13): 9434-9443, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38507716

RESUMO

Electrocatalytic synthesis of hydrogen peroxide (H2O2) in acidic media is an efficient and eco-friendly approach to produce inherently stable H2O2, but limited by the lack of selective and stable catalysts under industrial-relevant current densities. Herein, we report a diatomic cobalt catalyst for two-electron oxygen reduction to efficiently produce H2O2 at 50-400 mA cm-2 in acid. Electrode kinetics study shows a >95% selectivity for two-electron oxygen reduction on the diatomic cobalt sites. In a flow cell device, a record-high production rate of 11.72 mol gcat-1 h-1 and exceptional long-term stability (100 h) are realized under high current densities. In situ spectroscopic studies and theoretical calculations reveal that introducing a second metal into the coordination sphere of the cobalt site can optimize the binding strength of key H2O2 intermediates due to the downshifted d-band center of cobalt. We also demonstrate the feasibility of processing municipal plastic wastes through decentralized H2O2 production.

3.
J Am Chem Soc ; 145(8): 4819-4827, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36790150

RESUMO

Heterogeneous catalysts containing diatomic sites are often hypothesized to have distinctive reactivity due to synergistic effects, but there are limited approaches that enable the convenient production of diatomic catalysts (DACs) with diverse metal combinations. Here, we present a general synthetic strategy for constructing a DAC library across a wide spectrum of homonuclear (Fe2, Co2, Ni2, Cu2, Mn2, and Pd2) and heteronuclear (Fe-Cu, Fe-Ni, Cu-Mn, and Cu-Co) bimetal centers. This strategy is based on an encapsulation-pyrolysis approach, wherein a porous material-encapsulated macrocyclic complex mediates the structure of DACs by preserving the main body of the molecular framework during pyrolysis. We take the oxygen reduction reaction (ORR) as an example to show that this DAC library can provide great opportunities for electrocatalyst development by unlocking an unconventional reaction pathway. Among all investigated sites, Fe-Cu diatomic sites possess exceptional high durability for ORR because the Fe-Cu pairs can steer elementary steps in the catalytic cycle and suppress the troublesome Fenton-like reactions.

4.
Angew Chem Int Ed Engl ; 62(4): e202214516, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36420958

RESUMO

Single crystal surfaces with highly coordinated sites very often hold high specific activities toward oxygen reduction reaction (ORR) and others. Transposing their high specific activity to practical high-surface-area electrocatalysts remains challenging. Here, ultrathin Pt(100) alloy surface is constructed via epitaxial growth. The surface shows 3.1-6.9 % compressive strain and bulk-like characteristics as demonstrated by site-probe reactions and different spectroscopies. Its ORR activity exceeds that of bulk Pt3 Ni(100) and Pt(111) and presents a 19-fold increase in specific activity and a 13-fold increase in mass activity relative to commercial Pt/C. Moreover, the electrochemically active surface area (ECSA) is increased by 4-fold compared to traditional thin films (e.g. NSTF), which makes the catalyst more tolerant to voltage loss at high current densities under fuel cell operation. This work broadens the family of extended surface catalysts and highlights the knowledge-driven approach in the development of advanced electrocatalysts.

5.
Opt Express ; 28(25): 38184-38195, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33379636

RESUMO

In this study, AlGaInP red light emitting diodes with sizes ranging from 5 to 50 micrometers were fabricated and characterized. The atomic layer deposition technology is applied to coat a layer of silicon dioxide for passivation and protection. The top emission area is covered by ITO layer to maximize the optical output. From the optical measurement, the linewidth and emission peaks shift very little among different current levels (from 30 to 150 A/cm2). High current level lifetests are performed and a 15 µm ALD device can last 27 hours of continuous operation at 100 A/cm2 before their diode junction failed. A much shorter lifetime of 5.32 hours was obtained when the driving current is raised to 400 A/cm2. When the same condition was applied to 15 µm PECVD devices, 25 hours and 4.33 hours are registered for 100 A/cm2 and 400 A/cm2 tests, respectively. The cross-sectional SEM reveals the voids, defects, and dark lines developed during the aging tests, and most of them are caused by top contact failure. The surface layers of ITO and SiO2 were melted and the dark lines which were originated from the top surface propagated through the device and led to the eventual failure of the diode. The optical intensity degradation slopes of different sizes of devices indicate a large device can last longer in this accelerated aging test. The efficiencies of the devices are also evaluated by the ABC model and the fitted bimolecular coefficient ranges from 1.35 to 3.40×10-10 cm3/s.

6.
Australas Phys Eng Sci Med ; 37(4): 665-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25217964

RESUMO

The ability of human memory declines due to normal aging and cognitive diseases, which means that everyone will eventually be affected by this problem. Fortunately, memory ability can be improved by training, and early detection and treatment can even actively prevent serious memory loss. Based on this principle, we aimed to identify a method for estimating the memory ability in order to slow the progression of memory loss. Numerous studies have found that coupling between the theta and gamma bands (also referred to as theta-gamma synchronization) reflect memory processes, with this being more pronounced when maintaining working memory. This study measured the extent of theta-gamma synchronization, and used a wavelet transform to observe the activity in the theta and gamma bands during a visuospatial memory task. The findings showed that there was a pronounced change during the encoding and retrieval phases of a working-memory task, and a significant correlation between the rate of correct responses and the synchronization index in the parietal brain area. We propose that the extent of theta-gamma synchronization can be used to estimate the working-memory ability. The further application of theta-gamma synchronization in both clinical and home situations may be expected in the future.


Assuntos
Sincronização de Fases em Eletroencefalografia/fisiologia , Ritmo Gama/fisiologia , Rememoração Mental/fisiologia , Percepção Espacial/fisiologia , Memória Espacial/fisiologia , Ritmo Teta/fisiologia , Adulto , Algoritmos , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Reconhecimento Automatizado de Padrão/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise e Desempenho de Tarefas , Análise de Ondaletas
7.
Asia Pac J Clin Nutr ; 17 Suppl 1: 95-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18296311

RESUMO

In knowledge-based economies, nutrition concepts evolve with advances in agriculture. As people around the world become more health conscious, national health becomes one of the main directives for agricultural policies, including that of functional foods and their global markets. This article evaluates the development of the functional food industry in Taiwan and other countries through analysis of R&D capacity and bibliometrics. It attempts to identify future trends in nutrition with technology foresight research. Taiwan has a wide variety of indigenous herbal plants, although its functional food related literature is not large compared with some other Asian countries. However, there are quality papers on the immunologic functions of edible plants Globally there is much interest in edible plants with antioxidant activity and those phyto-nutrients which might help reduce the burden of chronic illness as well as in the nutrigenomics that will lead to the design of foods with these properties. To make the most of available agricultural resources, countries like Taiwan should relate agricultural development to the nutritional status of their populations. This strategy will add significant value to global agriculture.


Assuntos
Agricultura/métodos , Nutrigenômica , Fenômenos Fisiológicos da Nutrição/fisiologia , Plantas Comestíveis , Agricultura/normas , Animais , Alimentos Orgânicos , Humanos , Fenômenos Fisiológicos da Nutrição/genética , Valor Nutritivo , Plantas Geneticamente Modificadas , Taiwan
8.
J Pharmacol Sci ; 99(1): 68-76, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16127242

RESUMO

The aim of the present study was to determine whether the possible occurrence of renal ischemia and damage during heatstroke can be suppressed by prior administration of L-N6-(1-iminoethyl) lysine (L-NIL), a selective inducible nitric oxide synthase (iNOS) inhibitor. Urethane-anesthetized rats were exposed to heat stress (43 degrees C) to induce heatstroke. Control rats were exposed to 24 degrees C. Mean arterial pressure and renal blood flow after the onset of heatstroke both were significantly lower in vehicle-treated heatstroke rats than in normothermic controls. However, both the body temperature and renal damage scores were greater in vehicle-treated heatstroke rats compared with normothermic controls. Plasma nitric oxide (NO), creatinine, and blood urea nitrogen (BUN), as well as the renal immunoreactivity of iNOS and peroxynitrite all were significantly higher in vehicle-treated heatstroke rats compared with their normothermic controls. Pretreatment with L-NIL (3 mg/kg, administered intravenously and immediately at the onset of heat stress) significantly attenuated heatstroke-induced hyperthermia, arterial hypotension, renal ischemia and damage, increased renal levels of immunoreactivity of iNOS and peroxynitrite, and increased plasma levels of NO, creatinine, and BUN. Accordingly, pretreatment with L-NIL significantly improved survival during heatstroke. The results suggest that selective inhibition of iNOS-dependent NO and peroxynitrite formation protects against renal ischemia and damage during heatstroke by reducing hyperthermia and arterial hypotension.


Assuntos
Golpe de Calor/tratamento farmacológico , Isquemia/prevenção & controle , Rim/irrigação sanguínea , Lisina/análogos & derivados , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Animais , Pressão Sanguínea/efeitos dos fármacos , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Febre/prevenção & controle , Frequência Cardíaca/efeitos dos fármacos , Golpe de Calor/etiologia , Golpe de Calor/patologia , Hipotensão/prevenção & controle , Isquemia/etiologia , Isquemia/patologia , Rim/patologia , Lisina/farmacologia , Masculino , Óxido Nítrico/sangue , Ácido Peroxinitroso/metabolismo , Ratos , Ratos Sprague-Dawley , Circulação Renal/efeitos dos fármacos , Fatores de Tempo
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