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1.
Chem Commun (Camb) ; 60(51): 6556-6559, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38845407

RESUMO

Herein, a novel strategy is presented for the photoinduced decarboxylative and dehydrogenative cross-coupling of a wide range of α-fluoroacrylic acids with hydrogermanes. This methodology provides an efficient and robust approach for producing various germylated monofluoroalkenes with excellent stereoselectivity within a brief photoirradiation period. The feasibility of this reaction has been demonstrated through gram-scale reaction, conversion of germylated monofluoroalkenes, and modification of complex organic molecules.

2.
Heliyon ; 8(12): e12351, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36582705

RESUMO

Delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) is a disease with an incomplete pathological mechanism, long treatment time, and uncertain factors affecting the therapeutic effect. This study explored prognostic factors for DEACMP patients treated with hyperbaric oxygen therapy (HBOT) in 15 hospitals in China. The findings might provide a theoretical basis for further improving the prognosis of DEACMP patients. In this study, data from 330 patients with DEACMP who were admitted to HBOT centers of 15 hospitals in Hunan Province (China) from June 2015 to June 2020 were retrospectively analyzed, and their medical records related to disease prognosis were collected and followed up by telephone. Univariate and multivariate analyses were used to identify independent risk factors for the prognosis of DEACMP patients after HBOT. Univariate analysis revealed 11 possible prognostic factors. Consistent with univariate analysis, multivariate analysis found that underlying diseases (Odds radio(OR) = 2.886, P = 0.048), hypermyotonia (OR = 5.2558, P = 0.008), and HBOT pressure no less Than 2.3 atm absolute (ATA) ((OR = 7.812, P = 0.004) were identified as independent prognostic factors among 20 variables for poor prognosis of DEACMP patients treated with HBOT in the study. This multicenter retrospective analysis revealed that the adverse prognostic markers for DEACMP patients treated with HBOT might be underlying diseases, hypermyotonia, and an HBOT pressure of 2.3 ATA or higher.

3.
IEEE Trans Neural Netw Learn Syst ; 32(8): 3677-3689, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32857699

RESUMO

Ordinal regression (OR) is one of the most important machine learning tasks. The kernel method is a major technique to achieve nonlinear OR. However, traditional kernel OR solvers are inefficient due to increased complexity introduced by multiple ordinal thresholds as well as the cost of kernel computation. Doubly stochastic gradient (DSG) is a very efficient and scalable kernel learning algorithm that combines random feature approximation with stochastic functional optimization. However, the theory and algorithm of DSG can only support optimization tasks within the unique reproducing kernel Hilbert space (RKHS), which is not suitable for OR problems where the multiple ordinal thresholds usually lead to multiple RKHSs. To address this problem, we construct a kernel whose RKHS can contain the decision function with multiple thresholds. Based on this new kernel, we further propose a novel DSG-like algorithm, DSGOR. In each iteration of DSGOR, we update the decision functional as well as the function bias with appropriately set learning rates for each. Our theoretic analysis shows that DSGOR can achieve O(1/t) convergence rate, which is as good as DSG, even though dealing with a much harder problem. Extensive experimental results demonstrate that our algorithm is much more efficient than traditional kernel OR solvers, especially on large-scale problems.

4.
Artigo em Inglês | MEDLINE | ID: mdl-30332846

RESUMO

With regional socio-economic development and increasing population, the structure and function of terrestrial ecosystem environments on the earth's surface have changed markedly. Ecological shelter zone reconstruction (ESZR) is an ecosystem restoration and conservation project, which aims to ensure the safety of the ecological environments of-regions and basins. We selected the upper reaches of the Yangtze River (from Yibin to Chongqing) as the study area and determined the connotation of ESZR. At the same time, the planning scope and construction content of the ecological barrier in this specific region have been preliminarily explored. Meanwhile, a set of related planning methods was proposed, the ecological effects of which were quantitatively assessed and confirmed through the calculation of ESVs. Compared with the conditions in 2005, the study showed that the value of the services of the whole ecosystem augmented significantly under the slope classification, increasing by 103.23%. At the same time, the land use pattern has been optimized, and the vegetation coverage has been enhanced. The ESZR can effectively improve the ecosystem service function of slope land (mainly slope > 25°) and the regional ecological environment, solve the rocky desertification of the study area and provide an effective decision in relation to supporting regional green sustainable development.


Assuntos
Conservação dos Recursos Naturais , Desenvolvimento Econômico , Ecossistema , China , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Rios
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