In this paper, the contents and various forms of Cd, Cu, Zn and Pb in the sediments of the Xiangjiang River have been investigated. The presentation of this paper focuses on the various forms and characteristics of th...In this paper, the contents and various forms of Cd, Cu, Zn and Pb in the sediments of the Xiangjiang River have been investigated. The presentation of this paper focuses on the various forms and characteristics of the heavy metals in the column sediments at Xiawan Port of Zhuzhou, which has been severely polluted by a metallurgical plant.The forms of the heavy metals discussed in this paper are: The concentration of the exchangeable forms of Cd, Cu, Zn and Pb, in the forms of carbonates and Fe/ Mn oxide in water, the combination of Cu with organic matter and form, and the proportion of the residue form at each section have been studied.展开更多
Unsafe abortions constitute a public health problem. It is one of the causes of maternal mortality in the world and particularly in developing countries. Despite the progress made, maternal mortality remains high in C...Unsafe abortions constitute a public health problem. It is one of the causes of maternal mortality in the world and particularly in developing countries. Despite the progress made, maternal mortality remains high in Cameroon. The scarcity and disparity of data on abortions lead to a lack of strong evidence to advocate to decision-makers on the extent of the problems associated with abortions in Cameroon. Our objective is to estimate the rates of mortalities and complications related to unsafe abortions, as well as the difficulties of accessing safe abortions in Cameroon. We will carry out a systematic and meta-analytical review in the biomedical databases MEDLINE (Pubmed), Google Scholar and African Journal Online (AJOL) concerning unsafe abortions and/or difficulties in accessing safe abortions in Cameroon, without date or language restriction. Gray literature will be also consulted. Two authors will simultaneously select the studies and data extraction will be done using a Google Form. Proportions will be estimated on a random-effect model. The I<sup>2</sup> and Q statistics will be used to assess the extent of heterogeneity across the studies. The outcome of both the quantitative and qualitative parts of the study will be commented. Death and morbidity due to abortions can be prevented. A concerted multidisciplinary and multicentric action would be essential.展开更多
目的整体评价清浊祛毒丸治疗慢性前列腺炎的临床疗效以及安全性,为临床应用提供科学依据。方法检索Web of science、PubMed、中国知网、万方和维普数据库,搜集自清浊祛毒丸上市(2002年)至2020年10月已发表的关于清浊祛毒丸治疗慢性前列...目的整体评价清浊祛毒丸治疗慢性前列腺炎的临床疗效以及安全性,为临床应用提供科学依据。方法检索Web of science、PubMed、中国知网、万方和维普数据库,搜集自清浊祛毒丸上市(2002年)至2020年10月已发表的关于清浊祛毒丸治疗慢性前列腺炎的临床随机对照试验。由2名研究人员根据纳入和排除标准独立完成文献的筛选、资料提取及质量评价工作。分析两组结果的总有效率、NIH-CPSI评分和不良反应发生率。结果最终纳入6篇随机对照试验,共679例患者。两组的总有效率:[RR=1.22,95%CI(1.05,1.42),P=0.008];NIH-CPSI评分:[MD=-3.29,95%CI(-6.11,-0.48),P=0.02];不良反应发生率:[RR=1.08,95%CI(0.65,1.78),P=0.76]。结论清浊祛毒丸参与干预的试验组比对照组总有效率高、NIP-CPSI评分降低更明显,且较为安全。展开更多
The two-photon state with spatial entanglement is an essential resource for testing fundamental laws of quantum mechanics and various quantum applications.Its creation typically relies on spontaneous parametric downco...The two-photon state with spatial entanglement is an essential resource for testing fundamental laws of quantum mechanics and various quantum applications.Its creation typically relies on spontaneous parametric downconversion in bulky nonlinear crystals where the tunability of spatial entanglement is limited.Here,we predict that ultrathin nonlinear lithium niobate metasurfaces can generate and diversely tune spatially entangled photon pairs.The spatial properties of photons including the emission pattern,rate,and degree of spatial entanglement are analyzed theoretically with the coupled mode theory and Schmidt decomposition method.We show that by leveraging the strong angular dispersion of the metasurface,the degree of spatial entanglement quantified by the Schmidt number can be decreased or increased by changing the pump laser wavelength and a Gaussian beam size.This flexibility can facilitate diverse quantum applications of entangled photon states generated from nonlinear metasurfaces.展开更多
The meniscus plays an important role in the biomechanical function of the knee joint,but knee osteoarthritis(OA)deteriorates the mechanical properties of the meniscus.Thus understanding the mechanical behaviour of the...The meniscus plays an important role in the biomechanical function of the knee joint,but knee osteoarthritis(OA)deteriorates the mechanical properties of the meniscus.Thus understanding the mechanical behaviour of the OA meniscus is very important.This study aimed to assess the quasi-static nonlinear mechanical behaviours of the three zones of the OA meniscus by a proposed meso-indentation method,and further to investigate its nonlinear mechanical responses under the stance.Four pairs of menisci were harvested from OA patients during total knee arthroplasty.One pair of the menisci was first used for the histological analysis.Binocular fringe projection technology was then employed to reconstruct the morphology of the other three pairs of the menisci.Subsequently,a meso-indentation method was proposed to characterize the nonlinear behaviors of the meniscus zones,moreover,the hyperelastic model(HEM)together with the Hertz’s elastic model(EM)was used to fit the indentation force-depth curves of the meniscus zones.Furthermore,the fitted HEM and EM materials parameters were used to simulate the mechanical response of the meniscus in the stance by two simplified meniscus models.The results showed that the type III collagen widely existed in the OA menisci,and the red-white zone exhibited the best mechanical performance,and the 3-term Mooney-Rivlin model was the best descriptor for the nonlinear mechanical characterization of the three zones.Moreover,the stress or strain distributions of the simplified meniscus models differed significantly between the HEM and EM under the stance,and the EM underestimated the mechanical behaviours of the meniscus.The current work generally provides a novel testing method to study the nonlinear mechanical behaviour of soft biological materials,and is specifically helpful to understand the nonlinear mechanical behaviour of the OA meniscus for which the HEM should be used in the meniscus-related biomechanical studies.展开更多
提出了一种基于卷积神经网络的物品矢量检测识别方法:ACDet(self-attention and concatenation based detector),旨在解决照度变化下密集无序药品包装轮廓的高效检测问题。该方法采用组合图像增强技术提升模型学习物品外观特征的能力,...提出了一种基于卷积神经网络的物品矢量检测识别方法:ACDet(self-attention and concatenation based detector),旨在解决照度变化下密集无序药品包装轮廓的高效检测问题。该方法采用组合图像增强技术提升模型学习物品外观特征的能力,对计算模块C2F-A(C2F with attention)采用多条梯度流输出来进行多维度的强化自我注意力增强,包括特征维度和空间维度。设计的WConcat(weighted concatenation)模块可以对不同层次的特征图进行加权拼接并捕捉更关键的特征图,从而使网络具备更好的认知能力。在医药案例数据集(cancer pathological and pharmaceutical dataset,CPPD)实验中实现了81.0%的mAP(mean average precision),79.5%的Smoot hmAP,平均领先其他YOLO(you only look once)架构的模型5.5%~16.6%,在公开数据集平均领先0.7%~6.9%。同时,零样本测试中复核成功率达到99.9%。研究结果显示,ACDet能克服复杂检测场景难题,实现网络鲁棒性提升及轻量化,为工业智能化生产提供了技术支持。展开更多
文摘In this paper, the contents and various forms of Cd, Cu, Zn and Pb in the sediments of the Xiangjiang River have been investigated. The presentation of this paper focuses on the various forms and characteristics of the heavy metals in the column sediments at Xiawan Port of Zhuzhou, which has been severely polluted by a metallurgical plant.The forms of the heavy metals discussed in this paper are: The concentration of the exchangeable forms of Cd, Cu, Zn and Pb, in the forms of carbonates and Fe/ Mn oxide in water, the combination of Cu with organic matter and form, and the proportion of the residue form at each section have been studied.
文摘Unsafe abortions constitute a public health problem. It is one of the causes of maternal mortality in the world and particularly in developing countries. Despite the progress made, maternal mortality remains high in Cameroon. The scarcity and disparity of data on abortions lead to a lack of strong evidence to advocate to decision-makers on the extent of the problems associated with abortions in Cameroon. Our objective is to estimate the rates of mortalities and complications related to unsafe abortions, as well as the difficulties of accessing safe abortions in Cameroon. We will carry out a systematic and meta-analytical review in the biomedical databases MEDLINE (Pubmed), Google Scholar and African Journal Online (AJOL) concerning unsafe abortions and/or difficulties in accessing safe abortions in Cameroon, without date or language restriction. Gray literature will be also consulted. Two authors will simultaneously select the studies and data extraction will be done using a Google Form. Proportions will be estimated on a random-effect model. The I<sup>2</sup> and Q statistics will be used to assess the extent of heterogeneity across the studies. The outcome of both the quantitative and qualitative parts of the study will be commented. Death and morbidity due to abortions can be prevented. A concerted multidisciplinary and multicentric action would be essential.
文摘目的整体评价清浊祛毒丸治疗慢性前列腺炎的临床疗效以及安全性,为临床应用提供科学依据。方法检索Web of science、PubMed、中国知网、万方和维普数据库,搜集自清浊祛毒丸上市(2002年)至2020年10月已发表的关于清浊祛毒丸治疗慢性前列腺炎的临床随机对照试验。由2名研究人员根据纳入和排除标准独立完成文献的筛选、资料提取及质量评价工作。分析两组结果的总有效率、NIH-CPSI评分和不良反应发生率。结果最终纳入6篇随机对照试验,共679例患者。两组的总有效率:[RR=1.22,95%CI(1.05,1.42),P=0.008];NIH-CPSI评分:[MD=-3.29,95%CI(-6.11,-0.48),P=0.02];不良反应发生率:[RR=1.08,95%CI(0.65,1.78),P=0.76]。结论清浊祛毒丸参与干预的试验组比对照组总有效率高、NIP-CPSI评分降低更明显,且较为安全。
基金supported by the Australian Research Council(DP190101559,CE200100010).
文摘The two-photon state with spatial entanglement is an essential resource for testing fundamental laws of quantum mechanics and various quantum applications.Its creation typically relies on spontaneous parametric downconversion in bulky nonlinear crystals where the tunability of spatial entanglement is limited.Here,we predict that ultrathin nonlinear lithium niobate metasurfaces can generate and diversely tune spatially entangled photon pairs.The spatial properties of photons including the emission pattern,rate,and degree of spatial entanglement are analyzed theoretically with the coupled mode theory and Schmidt decomposition method.We show that by leveraging the strong angular dispersion of the metasurface,the degree of spatial entanglement quantified by the Schmidt number can be decreased or increased by changing the pump laser wavelength and a Gaussian beam size.This flexibility can facilitate diverse quantum applications of entangled photon states generated from nonlinear metasurfaces.
基金supported by the National Nature Science Foundation of China(Grant Nos.32171307,12372307,12172089,61821002 and 82102567)the Basic Research Plan Natural Science Foundation of Jiangsu Province(Grant No.BK20232023)+1 种基金the Nature Science Foundation of Jiangsu Province(Grant No.BK20200144)the Postgraduate Research and Practice Innovation Program of Jiangsu Province(Grant No.5007032303).
文摘The meniscus plays an important role in the biomechanical function of the knee joint,but knee osteoarthritis(OA)deteriorates the mechanical properties of the meniscus.Thus understanding the mechanical behaviour of the OA meniscus is very important.This study aimed to assess the quasi-static nonlinear mechanical behaviours of the three zones of the OA meniscus by a proposed meso-indentation method,and further to investigate its nonlinear mechanical responses under the stance.Four pairs of menisci were harvested from OA patients during total knee arthroplasty.One pair of the menisci was first used for the histological analysis.Binocular fringe projection technology was then employed to reconstruct the morphology of the other three pairs of the menisci.Subsequently,a meso-indentation method was proposed to characterize the nonlinear behaviors of the meniscus zones,moreover,the hyperelastic model(HEM)together with the Hertz’s elastic model(EM)was used to fit the indentation force-depth curves of the meniscus zones.Furthermore,the fitted HEM and EM materials parameters were used to simulate the mechanical response of the meniscus in the stance by two simplified meniscus models.The results showed that the type III collagen widely existed in the OA menisci,and the red-white zone exhibited the best mechanical performance,and the 3-term Mooney-Rivlin model was the best descriptor for the nonlinear mechanical characterization of the three zones.Moreover,the stress or strain distributions of the simplified meniscus models differed significantly between the HEM and EM under the stance,and the EM underestimated the mechanical behaviours of the meniscus.The current work generally provides a novel testing method to study the nonlinear mechanical behaviour of soft biological materials,and is specifically helpful to understand the nonlinear mechanical behaviour of the OA meniscus for which the HEM should be used in the meniscus-related biomechanical studies.
文摘提出了一种基于卷积神经网络的物品矢量检测识别方法:ACDet(self-attention and concatenation based detector),旨在解决照度变化下密集无序药品包装轮廓的高效检测问题。该方法采用组合图像增强技术提升模型学习物品外观特征的能力,对计算模块C2F-A(C2F with attention)采用多条梯度流输出来进行多维度的强化自我注意力增强,包括特征维度和空间维度。设计的WConcat(weighted concatenation)模块可以对不同层次的特征图进行加权拼接并捕捉更关键的特征图,从而使网络具备更好的认知能力。在医药案例数据集(cancer pathological and pharmaceutical dataset,CPPD)实验中实现了81.0%的mAP(mean average precision),79.5%的Smoot hmAP,平均领先其他YOLO(you only look once)架构的模型5.5%~16.6%,在公开数据集平均领先0.7%~6.9%。同时,零样本测试中复核成功率达到99.9%。研究结果显示,ACDet能克服复杂检测场景难题,实现网络鲁棒性提升及轻量化,为工业智能化生产提供了技术支持。
