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1.
Small ; : e2403292, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958094

RESUMO

Antimony selenide (Sb2Se3) has sparked significant interest in high-efficiency photovoltaic applications due to its advantageous material and optoelectronic properties. In recent years, there has been considerable development in this area. Nonetheless, defects and suboptimal [hk0] crystal orientation expressively limit further device efficiency enhancement. This study used Zinc (Zn) to adjust the interfacial energy band and strengthen carrier transport. For the first time, it is discovered that the diffusion of Zn in the cadmium sulfide (CdS) buffer layer can affect the crystalline orientation of the Sb2Se3 thin films in the superstrate structure. The effect of Zn diffusion on the morphology of Sb2Se3 thin films with CdxZn1-xS buffer layer has been investigated in detail. Additionally, Zn doping promotes forming Sb2Se3 thin films with the desired [hk1] orientation, resulting in denser and larger grain sizes which will eventually regulate the defect density. Finally, based on the energy band structure and high-quality Sb2Se3 thin films, this study achieves a champion power conversion efficiency (PCE) of 8.76%, with a VOC of 458 mV, a JSC of 28.13 mA cm-2, and an FF of 67.85%. Overall, this study explores the growth mechanism of Sb2Se3 thin films, which can lead to further improvements in the efficiency of Sb2Se3 solar cells.

2.
J Phys Chem Lett ; 15(9): 2301-2310, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38386516

RESUMO

The brain's function can be dynamically reconfigured through a unified neuron-synapse architecture, enabling task-adaptive network-level topology for energy-efficient learning and inferencing. Here, we demonstrate an organic neuristor utilizing a ferroelectric-electrolyte dielectric interface. This neuristor enables tunable short- to long-term plasticity and reconfigurable logic-in-memory functions by controlling the interfacial interaction between electrolyte ions and ferroelectric dipoles. Notably, the short-term plasticity of the organic neuristor allows for power-efficient reservoir computing in edge-computing scenarios, exhibiting impressive recognition accuracy, including images (90.6%) and acoustic signals (97.7%). For high-performance computing tasks, the neuristor based on long-term plasticity and logic-in-memory operations can construct all of the hardware circuits of a binarized neural network (BNN) within a unified framework. The BNN demonstrates excellent noise tolerance, achieving high recognition accuracies of 99.2% and 86.4% on the MNIST and CIFAR-10 data sets, respectively. Consequently, our research sheds light on the development of power-efficient artificial intelligence systems.

3.
Adv Sci (Weinh) ; 10(31): e2304246, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37691096

RESUMO

The efficiency of antimony selenide (Sb2 Se3 ) solar cells is still limited by significant interface and deep-level defects, in addition to carrier recombination at the back contact surface. This paper investigates the use of lithium (Li) ions as dopant for Sb2 Se3 films, using lithium hydroxide (LiOH) as a dopant medium. Surprisingly, the LiOH solution not only reacts at the back surface of the Sb2 Se3 film but also penetrate inside the film along the (Sb4 Se6 )n molecular chain. First, the Li ions modify the grain boundary's carrier type and create an electric field between p-type grain interiors and n-type grain boundary. Second, a gradient band structure is formed along the vertical direction with the diffusion of Li ions. Third, carrier collection and transport are improved at the surface between Sb2 Se3 and the Au layer due to the reaction between the film and alkaline solution. Additionally, the diffusion of Li ions increases the crystallinity, orientation, surface evenness, and optical electricity. Ultimately, the efficiency of Sb2 Se3 solar cells is improved to 7.57% due to the enhanced carrier extraction, transport, and collection, as well as the reduction of carrier recombination and deep defect density. This efficiency is also a record for CdS/Sb2 Se3 solar cells fabricated by rapid thermal evaporation.

4.
J Obstet Gynaecol Res ; 48(11): 2926-2934, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36054651

RESUMO

OBJECTIVE: To review of our hospital's experiences in transvaginal natural orifice transluminal endoscopic surgery (vNOTES) and challenges we encountered in performance of the procedure, so as to provide help to medical institutions who are preparing to carry out vNOTES. METHODS: We retrospectively analyzed the data of all patients receiving vNOTES in our hospital from April 2018 to May 2021. Data we collected cover the general characteristics, perioperative outcomes, and complications of the patients. RESULTS: A total of 1147 patients underwent vNOTES in the past 3 years at our hospital. The total numbers of adnexal surgery, myomectomy, hysterectomy, pelvic floor reconstruction surgery, and malignant tumor surgery performed via vNOTES were 902, 98, 82, 51, and 14, respectively. Eighteen patients were converted to transabdominal laparoscopic surgery. A total of 38 patients had complications according to Clavien-Dindo classification, and the total complication rate was 3.31%. Among these cases of complications, 27 were Grade I, 4 were Grade II, and 7 were Grade III. No complications of Grade IV or V were reported. CONCLUSION: The application of vNOTES is safe and feasible for most gynecological surgeries. Moreover, hospitals with traditional laparoscopic equipment are advised to try this technique as there is no need to purchase additional expensive equipment. However, since vNOTES represents a novel approach, the long-term complications and efficacy associated with this technique are pending to be verified through large-scale prospective multicenter randomized controlled studies.


Assuntos
Laparoscopia , Cirurgia Endoscópica por Orifício Natural , Criança , Feminino , Humanos , Estudos Retrospectivos , Estudos Prospectivos , Cirurgia Endoscópica por Orifício Natural/métodos , Histerectomia/métodos , Laparoscopia/métodos , Hospitais , Vagina/cirurgia
5.
Int Urogynecol J ; 33(7): 1917-1925, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34213602

RESUMO

INTRODUCTION AND HYPOTHESIS: Hysteropreservation and hysterectomy for uterine prolapse have been compared in several randomized controlled trials (RCTs), as the best treatment has not been definitively determined. This study aimed to summarize the available evidence in RCTs of hysteropreservation versus hysterectomy. METHODS: We performed electronic searches in the PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure databases for eligible RCTs from inception to June 2020. The relative risks (RRs) and weighted mean differences (WMDs) with corresponding 95% confidence intervals (CIs) were calculated for categorical and continuous variables using random-effects models. RESULTS: Twelve RCTs involving 1177 patients were selected for meta-analysis. There were no significant differences between hysteropreservation and hysterectomy for the incidences of recurrence (RR, 0.55; 95% CI, 0.26-1.19; P = 0.130) and reoperation (RR, 1.15; 95% CI, 0.56-2.37; P = 0.705). Moreover, neither hysteropreservation nor hysterectomy had any significant effect on the risk of constipation (RR, 0.72; 95% CI, 0.15-3.46; P = 0.681), voiding dysfunction (RR, 0.99; 95% CI, 0.54-1.84; P = 0.981), intraoperative bleeding (RR, 0.35; 95% CI, 0.05-2.26; P = 0.271), upper leg dullness (RR, 0.70; 95% CI, 0.15-3.17; P = 0.643), dyspareunia (RR, 1.47; 95% CI, 0.69-3.13; P = 0.317), and wound infection (RR, 1.38; 95% CI, 0.24-7.80; P = 0.714). Furthermore, hysteropreservation was associated with less intraoperative blood loss (WMD, -25.68; 95% CI, -44.39 to -6.96; P = 0.007), shorter duration of surgery (WMD, -11.30; 95% CI, -19.04 to -3.55; P = 0.004), and shorter duration of hospitalization (WMD, -0.63; 95% CI, -1.10 to -0.16; P = 0.009) compared with hysterectomy. CONCLUSION: This study found that both hysteropreservation and hysterectomy have similar effects on recurrence and reoperation rates, while hysteropreservation was superior to hysterectomy in reducing intraoperative blood loss and shortening the duration of surgery and hospitalization.


Assuntos
Dispareunia , Prolapso Uterino , Perda Sanguínea Cirúrgica , Dispareunia/cirurgia , Feminino , Humanos , Histerectomia/efeitos adversos , Reoperação , Prolapso Uterino/cirurgia
6.
J Sep Sci ; 44(20): 3777-3788, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34418299

RESUMO

A combinative method using high-performance liquid chromatography-electrochemical detection for fingerprinting and quantitative analysis was developed and successfully applied for the quality evaluation of Lophatherum gracile Brongn leaves collected from 21 geographical locations in China. In the fingerprint analysis, 18 common peaks were observed among the 21 samples, and 10 peaks were identified. Simultaneous quantification of the 10 components was conducted to interpret the variations in these compounds among the L. gracile Brongn leaves originating from different geographical locations. The correlation between the chromatograms and the antioxidant activities of the samples was further studied. The results indicated a linear correlation between the antioxidant activity and the total common peak areas of the fingerprints obtained by high-performance liquid chromatography-electrochemical detection. Importantly, it was found that high-performance liquid chromatography-electrochemical detection fingerprinting can not only determine the quantities of individual components present in such samples but also evaluate the antioxidant activities of the samples. The developed method is a valuable reference for the further study and development of L. gracile Brongn.


Assuntos
Antioxidantes/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Técnicas Eletroquímicas , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Poaceae/química , Antioxidantes/análise , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/análise , Compostos Fitoquímicos/análise , Picratos/antagonistas & inibidores , Extratos Vegetais/análise , Ácidos Sulfônicos/antagonistas & inibidores
7.
ACS Appl Mater Interfaces ; 13(17): 20336-20348, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33900063

RESUMO

A novel chemiresistive-type sensor for detecting sub-ppm NO2 has been fabricated using AuPt bimetal-decorated SnSe2 microflowers, which was synthesized by the hydrothermal treatment followed by in situ chemical reduction of the bimetal precursors on the surface of the petals of the microflowers. The as-prepared sensor registers a superior performance in detection of sub-ppm concentration of NO2. Functionalized by the AuPt bimetal, the SnSe2 microflower-based sensor shows a response of approximately 4.62 to 8 ppm NO2 at 130 °C. It is significantly higher than those of the sensors using the pristine SnSe2 (∼2.29) and the modified SnSe2 samples by a single metal, either Au (∼3.03) or Pt (∼3.97). The sensor demonstrates excellent long-term stability, signal repeatability, and selectivity to some typical interfering gaseous species including ammonia, acetone, formaldehyde, ethanol, methanol, benzene, CO2, SO2, and CO. The remarkable improvement of the sensitive characteristics could be induced by the electronic and chemical sensitization and the synergistic effect of the AuPt bimetal. Density functional theory (DFT) is implemented to calculate the adsorption states of NO2 on the sensing materials and thus to possibly reveal the sensing mechanism. The significantly enhanced response of the SnSe2-based sensor decorated with AuPt bimetallic nanoparticles has been found to be possibly caused by the orbital hybridization of O, Au, and Pt atoms leading to the redistribution of electrons, which is beneficial for NO2 molecules to obtain more electrons from the composite material.

8.
ACS Appl Mater Interfaces ; 11(32): 29029-29040, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31313913

RESUMO

Mesoporous ZnSe/ZnO heterojunctions were prepared by the in situ thermal oxidation of ZnSe at elevated temperatures in air. The partial replacement of selenium by oxygen in the ZnSe nanoflakes led to a highly porous microstructure with 8.2 nm mesopores distributed fairly uniformly within the formed heterojunction sample. The as-fabricated mesoporous ZnSe/ZnO heterojunction-based sensor exhibits an approximately 7.3-fold significantly higher response than those of both pristine ZnO- and ZnSe-based sensors when exposed to 8 ppm NO2 at 200 °C. This sensor also demonstrates excellent selectivity for methanol, ethanol, acetone, benzene, methylbenzene, ammonia, and formaldehyde. The significantly enhanced response of the ZnSe/ZnO-based sensor is due to the mesoporous microstructure during thermal oxidation of ZnSe to ZnO, yielding more active sites and the accumulation of electrons in the ZnO nanocrystals transferred between ZnSe/ZnO interfaces.

9.
Nanomaterials (Basel) ; 8(10)2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30347667

RESUMO

Two-dimensional (2D) nanomaterials have attracted a large amount of attention regarding gas sensing applications, because of their high surface-to-volume ratio and unique chemical or physical gas adsorption capabilities. As an important research method, theoretical calculations have been massively applied in predicting the potentially excellent gas sensing properties of these 2D nanomaterials. In this review, we discuss the contributions of theoretical calculations in the study of the gas sensing properties of 2D nanomaterials. Firstly, we elaborate on the gas sensing mechanisms of 2D layered nanomaterials, such as the traditional charge transfer mechanism, and a standard for distinguishing between physical and chemical adsorption, from the perspective of theoretical calculations. Then, we describe how to conduct a theoretical analysis to explain or predict the gas sensing properties of 2D nanomaterials. Thirdly, we discuss three important methods that have been applied in order to improve the gas sensing properties, that is, defect functionalization (vacancy, edge, grain boundary, and doping), heterojunctions, and electric fields. Among these strategies, theoretical calculations play a very important role in explaining the mechanisms underlying the enhanced gas sensing properties. Finally, we summarize both the advantages and limitations of the theoretical calculations, and present perspectives for further research on the 2D nanomaterials-based gas sensors.

10.
J Insect Physiol ; 59(10): 1065-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23973817

RESUMO

The fig tree, Ficus curtipes, hosts an obligate pollinating wasp, an undescribed Eupristina sp., but can also be pollinated by two inquiline (living in the burrow, nest, gall, or other habitation of another animal) wasps, Diaziella yangi and an undescribed Lipothymus sp. The two inquilines are unable to independently induce galls and depend on the galls induced by the obligate pollinator for reproduction and, therefore, normally enter receptive F. curtipes figs colonised by the obligate pollinators. However, sometimes the inquilines also enter figs that are not colonised by the pollinators, despite consequent reproductive failure. It is still unknown which signal(s) the inquilines use in entering the colonised and non-colonised figs. We conducted behavioural experiments to investigate several possible signals utilised by the inquilines in entering their host receptive figs. Our investigation showed that both inquiline species enter the receptive F. curtipes figs in response to the body odours of the obligate wasps and one of the main compounds emitted by the figs, 6-methyl-5-hepten-2-one. The compound was not found in the pollinator body odours, suggesting that the two inquiline wasps can utilise two signals to enter their host figs, which is significant for the evolution of the fig-fig wasp system. These inquilines could evolve to become mutualists of the figs if they evolve the ability to independently gall fig flowers; there is, however, another possibility that a monoecious Ficus species hosting such inquilines may evolve into a dioecious one if these inquilines cannot evolve the above-mentioned ability. Additionally, this finding provides evidence for the evolution of chemical communication between plants and insects.


Assuntos
Ficus/fisiologia , Heptanol/análogos & derivados , Cetonas , Simbiose , Vespas/fisiologia , Animais , Evolução Biológica , Sinais (Psicologia) , Feminino
11.
J Steroid Biochem Mol Biol ; 113(3-5): 177-81, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19150652

RESUMO

Gossypol has been proven to be a very effective male contraceptive. However, clinical trials showed that the major side effect of gossypol was hypokalemia. Gossypol occurs naturally as enantiomeric mixtures of (+)-gossypol and (-)-gossypol. The (-)-gossypol is found to be the active component of antifertility. 11beta-Hydroxysteroid dehydrogenase 2 (11betaHSD2) has been demonstrated to be a mineralocorticoid receptor (MR) protector by inactivating active glucocorticoids including corticosterone (CORT) in rats, and therefore mutation or suppression of 11betaHSD2 causes hypokalemia and hypertension. In the present study, the potency of gossypol enantiomers was tested for the inhibition of 11betaHSD1 and 2 in rat and human. Both (+) and (-)-gossypols showed a potent inhibition of 11betaHSD2 with the half maximal inhibitory concentration (IC(50)) of 0.61 and 1.33 microM for (+) and (-)-gossypols, respectively in rats and 1.05 and 1.90 microM for (+) and (-)-gossypols, respectively in human. The potency of gossypol to inhibit 11betaHSD1 was far less; the IC(50) was > or =100 microM for racemic gossypol. The gossypol-induced hypokalemia is likely associated with its potent inhibition of kidney 11betaHSD2.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 2/antagonistas & inibidores , Gossipol/química , Gossipol/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , 11-beta-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , 11-beta-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Carbenoxolona/metabolismo , Anticoncepcionais Masculinos/química , Anticoncepcionais Masculinos/metabolismo , Anticoncepcionais Masculinos/farmacologia , Relação Dose-Resposta a Droga , Gossipol/farmacologia , Humanos , Hipertensão/induzido quimicamente , Hipopotassemia/induzido quimicamente , Rim/efeitos dos fármacos , Rim/enzimologia , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Ratos , Ratos Sprague-Dawley , Estereoisomerismo
12.
Chemosphere ; 71(9): 1774-80, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18334265

RESUMO

The photolysis of simulating low concentration of hydrogen sulfide malodorous gas was studied under UV irradiation emitted by self-made microwave discharge electrodeless lamps (i.e. microwave UV electrodeless mercury lamp (185/253.7 nm) and iodine lamp (178.3/180.1/183/184.4/187.6/206.2 nm)). Experiments results showed that the removal efficiency (eta H2S) of hydrogen sulfide was decreased with increasing initial H2S concentration and increased slightly with gas residence time; H2S removal efficiency was decreased dramatically with enlarged pipe diameter. Under the experimental conditions with pipe diameter of 36 mm, gas flow rate of 0.42 standard l s(-1), eta H2S was 52% with initial H2S concentration of 19.5 mg m(-3) by microwave mercury lamp, the absolute removal amount (ARA) was 4.30 microg s(-1), and energy yield (EY) was 77.3 mg kW h(-1); eta H2S was 56% with initial H2S concentration of 18.9 mg m(-3) by microwave iodine lamp, the ARA was 4.48 microg s(-1), and the EY was 80.5mg kW h(-1). The main photolysis product was confirmed to be SO4(2-) with IC.


Assuntos
Sulfeto de Hidrogênio/química , Micro-Ondas , Raios Ultravioleta , Fotoquímica
13.
Huan Jing Ke Xue ; 28(7): 1627-31, 2007 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17891980

RESUMO

The photolysis of simulating carbon disulfide malodorous gas was studied under UV irradiation emitted by microwave electrodeless lamps. Experiments results show that the photolysis of carbon disulfide is determined by the initial concentration, residence time and gas humidity. When air velocity is 0.2 m/s, initial concentration is about 100 mg/m3, and gas humidity is about 40%, the conversion ratio of carbon disulfide can reach to 75% with microwave electrodeless mercury lamp and 50% with microwave electrodeless iodine lamp. The mechanism of carbon disulfide photolysis was further studied. It is concluded that the photolysis of carbon disulfide is probably a collective action of direct photolysis and *OH radical oxidation.


Assuntos
Poluentes Atmosféricos/química , Dissulfeto de Carbono/química , Micro-Ondas , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/efeitos da radiação , Dissulfeto de Carbono/análise , Dissulfeto de Carbono/efeitos da radiação , Eletrodos , Fotólise
14.
Space Med Med Eng (Beijing) ; 16(3): 231-4, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12934620

RESUMO

Based on the principle of thermal physiology, especially on the effect of the ambient temperature on head-neck skin temperatures, the paper discussed some general problems about detecting the suspected patient of SARS from large number of transferring people in public place according to the head-neck skin temperature during recently fight against SARS. Therefore several suggestions about how to improve and ensure the effectiveness and security of such detection were put forward.


Assuntos
Controle de Doenças Transmissíveis/métodos , Programas de Rastreamento/métodos , Síndrome Respiratória Aguda Grave/diagnóstico , Temperatura Cutânea , Cabeça , Humanos , Programas de Rastreamento/instrumentação , Pescoço , Termômetros
15.
Space Med Med Eng (Beijing) ; 15(2): 93-7, 2002 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12068890

RESUMO

OBJECTIVE: To study effect of simulated weightlessness on non-evaporative heat dissipation from different parts of the human body. METHOD: Body surface temperature distribution of five subjects was measured under -6 degrees head down bedrest for 7 d with HR-II infrared thermography. Non-evaporative heat dissipation was calculated with the heat exchange equations based on surface temperature. RESULT: The temperature difference between torso and extremities increased during bed rest, and the largest was 6.7 degrees C higher than the control on the 3rd day of bed rest. The part of non-evaporative heat dissipation from the torso increased about 6% and that from head-neck increased 2%. At the same time, the parts of heat dissipation from the upper and lower extremities decreased about 3% and 5% respectively. CONCLUSION: The parts of non-evaporative heat dissipation from different areas of the human body changed during simulated weightlessness. This result provided a basis for the flow distribution design of liquid cooling garment of EVA suit.


Assuntos
Repouso em Cama , Regulação da Temperatura Corporal/fisiologia , Temperatura Cutânea/fisiologia , Trajes Espaciais , Simulação de Ausência de Peso , Braço , Atividade Extraespaçonave , Cabeça , Decúbito Inclinado com Rebaixamento da Cabeça , Temperatura Alta , Humanos , Perna (Membro) , Termografia , Tórax
16.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 9(4): 368-371, 2001 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-12578582

RESUMO

For exploring pathogenesis of pyrimidine 5'-nucleotidase (P5'N) deficiency, a quantitative assay method for human erythrocyte pyrimidine 5'-nucleotidase was established. The specific substrate uridine monophosphate (UMP) of P5'N was used as ligand. The UPM-ADH-Sepharose 4B affinity column was prepared. P5'N of human erythrocyte was purified by ammonium sulfate fractionation and precipitation, ion chromatography and affinity chromatography. Rabbit anti-human P5'N antibody was acquired by immunizing rabbits with purified P5'N. Using rabbit anti-human antibody as the coated anti-body and HRP-rabbit anti-human antibody as demonstrated anti-body, the double antitody sandwich ELISA for quantitative assay of human erythrocyte P5'N was established after square rank trial, antigen blocked trial and antigen substituted test. Results showed that the titer of rabbit anti-human erythrocyte was 1:4 and the sensitivity of double antibody sandwich ELISA was 5 ng/ml. Its blocking rate was more than 95% and the rate of substitution less than 30%. The content of P5'N was (71.77 + 10.98) ng/mg NHP in normal human erythrocyte. A new ELISA method for quantitative determination of human erythrocyte P5'N was first established. It not only had high specificity and sensitivity but also could assay the minimun content of P5'N as 5 - 20 ng/ml. It could be a suitable method for large sample in clinics.

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