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1.
Opt Express ; 31(26): 44603-44610, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38178527

RESUMO

In this paper, we report for the first time on an all-multimode fiber spatiotemporal mode-locked figure-eight laser operating at 1.0 µm. This laser utilizes a multimode gain fiber and a nonlinear amplifying loop mirror mechanism. It can generate mode-locked noise-like pulses at different central wavelengths. Additionally, we observed the presence of a multi-soliton state within the cavity by reducing intracavity gain. This study contributes to a broader investigation of various pulse phenomena in spatiotemporal mode-locked lasers and provides valuable insights into further exploring the evolution of spatiotemporal dynamics in such systems.

2.
Glob Chang Biol ; 29(13): 3723-3746, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37026556

RESUMO

Climate has critical roles in the origin, pathogenesis and transmission of infectious zoonotic diseases. However, large-scale epidemiologic trend and specific response pattern of zoonotic diseases under future climate scenarios are poorly understood. Here, we projected the distribution shifts of transmission risks of main zoonotic diseases under climate change in China. First, we shaped the global habitat distribution of main host animals for three representative zoonotic diseases (2, 6, and 12 hosts for dengue, hemorrhagic fever, and plague, respectively) with 253,049 occurrence records using maximum entropy (Maxent) modeling. Meanwhile, we predicted the risk distribution of the above three diseases with 197,098 disease incidence records from 2004 to 2017 in China using an integrated Maxent modeling approach. The comparative analysis showed that there exist highly coincident niche distributions between habitat distribution of hosts and risk distribution of diseases, indicating that the integrated Maxent modeling is accurate and effective for predicting the potential risk of zoonotic diseases. On this basis, we further projected the current and future transmission risks of 11 main zoonotic diseases under four representative concentration pathways (RCPs) (RCP2.6, RCP4.5, RCP6.0, and RCP8.5) in 2050 and 2070 in China using the above integrated Maxent modeling with 1,001,416 disease incidence records. We found that Central China, Southeast China, and South China are concentrated regions with high transmission risks for main zoonotic diseases. More specifically, zoonotic diseases had diverse shift patterns of transmission risks including increase, decrease, and unstable. Further correlation analysis indicated that these patterns of shifts were highly correlated with global warming and precipitation increase. Our results revealed how specific zoonotic diseases respond in a changing climate, thereby calling for effective administration and prevention strategies. Furthermore, these results will shed light on guiding future epidemiologic prediction of emerging infectious diseases under global climate change.


Assuntos
Epidemias , Zoonoses , Animais , Incidência , Zoonoses/epidemiologia , Ecossistema , Mudança Climática , China/epidemiologia
3.
Alcohol Alcohol ; 58(1): 13-22, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36208184

RESUMO

AIMS: Behavior couples therapy (BCT) is widely considered to be effective in the treatment of substance use disorders. However, the effect size of BCT in different outcome measures, and at different time points requires further study to prove it. METHODS: Systematic searches were performed in various databases. Ultimately, we identified 12 studies, involving 19 randomized controlled trials. We used Hedges' g as the effect size, and all pooled analyses were performed using random-effects models. RESULTS: After treatment, BCT was superior to control conditions (either an active or inactive control group) in frequency of substance use (g = 0.17), substance use consequences (g = -0.28) and relationship satisfaction (g = 0.45). After a 12-month follow-up, BCT remained superior to control conditions in frequency of substance use (g = 0.32), substance use consequences (g = -0.34) and relationship satisfaction (g = 0.31). In addition, BCT was more effective in reducing the frequency of substance use than individual-based treatment (IBT) (g = 0.23). There was no significant relationship between the effect size of BCT and publication year (t = 0.92, P = 0.372), percentage of females (t = -0.02, P = 0.987) or the number of treatment sessions (t = -0.52, P = 0.609). CONCLUSIONS: BCT was superior to the control conditions in all three outcome measures after treatment and at follow-up, and showed a relatively large effect size for relationship satisfaction. Moreover, BCT was superior to IBT in reducing the frequency of substance use.


Assuntos
Terapia de Casal , Transtornos Relacionados ao Uso de Substâncias , Feminino , Humanos , Terapia Comportamental , Avaliação de Resultados em Cuidados de Saúde , Transtornos Relacionados ao Uso de Substâncias/terapia
4.
Psychiatry Res ; 317: 114861, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36179591

RESUMO

This meta-analysis mainly examined the effect size of exposure and response prevention (ERP) for obsessive-compulsive disorder (OCD) when compared with different control conditions, and the difference in the efficacy of different variants of ERP in the treatment of OCD. Thirty studies were included, involving 39 randomized controlled trials with 1793 participants, from 30 studies up to January 18, 2022. Hedge's g was calculated using random-effects models. The results showed that ERP had a definite effect on OCD (g = 0.37), and its effect was significant when the control condition was placebo (g = 0.97) or drug (g = 0.59). However, ERP did not show statistical differences with other therapies in improving OCD (g = -0.07). In addition, we found that both therapist and self-controlled exposure (at the same time as the therapist controls, self-control is exercised after the therapy session) and total response prevention can better improve OCD symptoms. In addition, compared with the control group, ERP reduced depression (g = 0.15) and anxiety symptoms (g = 0.23) in patients with OCD. Meta-regression results showed that the longer the length of sessions, the better the treatment effect (t = 2.41, p = 0.022).


Assuntos
Terapia Implosiva , Transtorno Obsessivo-Compulsivo , Humanos , Resultado do Tratamento , Transtorno Obsessivo-Compulsivo/terapia , Transtorno Obsessivo-Compulsivo/diagnóstico , Terapia Implosiva/métodos , Ansiedade
5.
Sci Rep ; 11(1): 940, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441823

RESUMO

A novel planar distributed three-beam electron gun with narrow beam separations is designed based on grids loaded sheet beam method. The dimensions of the three-beam gun in the y-O-z plane are determined using our basic theoretical design method developed for sheet beam gun. The results show that the profile of focusing electrode in the y-O-z plane is related to the beam width in the x-O-z plane. Then, the characteristics and parameters of three-beam array formation with their stability are analyzed thoroughly by adjustment of control grids in the x-O-z plane. Each of the beamlet obtained is with a small axial deviation of the two transverse waists. Based on the theoretical analysis and simulations, the planar three-beam electron gun is constructed with the beam voltage of 22 kV and the current of 3 [Formula: see text] 0.15 A. The average radius of 0.08 mm at each beam waist is obtained with the compression factor of 4 for the 0.18 mm beam tunnel radius. The beam waist can be achieved at about 4.4 mm away from the cathode with the axis separation about 0.46 mm for each of beamlet. Thus, the design method can be generally used to construct such type of narrow beam separation and planar distributed multiple beam electron gun for the miniaturization and integrated vacuum electron devices in millimeter wave and terahertz band.

6.
Sci Rep ; 10(1): 20159, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33214669

RESUMO

This paper presents design, fabrication and cold test of an ultra-wide band travelling wave tube (TWT) with planar alignment multiple pencil beams. The fundamental double-mode of staggered double vane slow wave structure (SDV-SWS) rather than the only one mode are put forward and adopted to match with the same electron beam to increase the bandwidth greatly. Simultaneous planar alignment multiple pencil beam tunnels are designed to improve interaction impedance and then to enhance output power, gain, efficiency, growth rate. The transmission performance of a two-stage 51-period SDV-TWT in G-band with structure attenuator between two sections shows that it indeed has an ultra-wideband performance from 81 to 110 GHz. By using computer numerical control machining, the SDV-SWS was manufactured and a detailed cold test was conducted. Good agreement is found at the wide band, where S21 is above - 5 dB and S11 is below - 10 dB. 3D PIC simulations with double-mode multiple-beam SDV-TWT within total length of 70 mm show that it can get a nearly 2120 W peak output power, a 42.5 dB corresponding gain and a 10.7% electron efficiency at 94 GHz with a 22.1 kV beam voltage and a 3 × 0.15A beam current. The 3 dB bandwidth of our double-mode SDV-TWT can achieve about 29 GHz.

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