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Deep Global Multiple-Scale and Local Patches Attention Dual-Branch Network for Pose-Invariant Facial Expression Recognition
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作者 Chaoji Liu Xingqiao Liu +1 位作者 Chong Chen Kang Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期405-440,共36页
Pose-invariant facial expression recognition(FER)is an active but challenging research topic in computer vision.Especially with the involvement of diverse observation angles,FER makes the training parameter models inc... Pose-invariant facial expression recognition(FER)is an active but challenging research topic in computer vision.Especially with the involvement of diverse observation angles,FER makes the training parameter models inconsistent from one view to another.This study develops a deep global multiple-scale and local patches attention(GMS-LPA)dual-branch network for pose-invariant FER to weaken the influence of pose variation and selfocclusion on recognition accuracy.In this research,the designed GMS-LPA network contains four main parts,i.e.,the feature extraction module,the global multiple-scale(GMS)module,the local patches attention(LPA)module,and the model-level fusion model.The feature extraction module is designed to extract and normalize texture information to the same size.The GMS model can extract deep global features with different receptive fields,releasing the sensitivity of deeper convolution layers to pose-variant and self-occlusion.The LPA module is built to force the network to focus on local salient features,which can lower the effect of pose variation and self-occlusion on recognition results.Subsequently,the extracted features are fused with a model-level strategy to improve recognition accuracy.Extensive experimentswere conducted on four public databases,and the recognition results demonstrated the feasibility and validity of the proposed methods. 展开更多
关键词 Pose-invariant FER global multiple-scale(GMS) local patches attention(LPA) model-level fusion
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Formation and ecological response of sand patches in the protection system of Shapotou section of the Baotou-Lanzhou railway,China
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作者 DUN Yaoquan QU Jianjun +4 位作者 KANG Wenyan LI Minlan LIU Bin WANG Tao SHAO Mei 《Journal of Arid Land》 SCIE CSCD 2024年第2期298-313,共16页
The development of bare patches typically signifies a process of ecosystem degradation.Within the protection system of Shapotou section of the Baotou-Lanzhou railway,the extensive emergence of bare sand patches poses ... The development of bare patches typically signifies a process of ecosystem degradation.Within the protection system of Shapotou section of the Baotou-Lanzhou railway,the extensive emergence of bare sand patches poses a threat to both stability and sustainability.However,there is limited knowledge regarding the morphology,dynamic changes,and ecological responses associated with these sand patches.Therefore,we analyzed the formation and development process of sand patches within the protection system and its effects on herbaceous vegetation growth and soil nutrients through field observation,survey,and indoor analysis methods.The results showed that sand patch development can be divided into three stages,i.e.,formation,expansion,and stabilization,which correspond to the initial,actively developing,and semi-fixed sand patches,respectively.The average dimensions of all sand patch erosional areas were found to be 7.72 m in length,3.91 m in width,and 0.32 m in depth.The actively developing sand patches were the largest,and the initial sand patches were the smallest.Throughout the stage of formation and expansion,the herbaceous community composition changed,and the plant density decreased by more than 50.95%.Moreover,the coverage and height of herbaceous plants decreased in the erosional area and slightly increased in the depositional lobe;and the fine particles and nutrients of soils in the erosional area and depositional lobe showed a decreasing trend.In the stabilization phases of sand patches,the area from the inlet to the bottom of sand patches becomes initially covered with crusts.Vegetation and 0-2 cm surface soil condition improved in the erosional area,but this improvement was not yet evident in the depositional lobe.Factors such as disturbance,climate change,and surface resistance to erosion exert notable influences on the formation and dynamics of sand patches.The results can provide evidence for the future treatment of sand patches and the management of the protection system of Shapotou section of the Baotou-Lanzhou railway. 展开更多
关键词 railway protection system sand patch MORPHOLOGY vegetation characteristic soil property
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Unveiling the adaptation strategies of woody plants in remnant forest patches to spatiotemporal urban expansion through leaf trait networks
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作者 Mengping Jian Jingyi Yang 《Forest Ecosystems》 SCIE CSCD 2024年第2期247-254,共8页
Background:With the expansion of urban areas,the remnants of forested areas play a crucial role in preserving biodiversity in urban environments.This study aimed to explore the impact of spatiotemporal urban expansion... Background:With the expansion of urban areas,the remnants of forested areas play a crucial role in preserving biodiversity in urban environments.This study aimed to explore the impact of spatiotemporal urban expansion on the networks of leaf traits in woody plants within remnant forest patches,thereby enhancing our understanding of plant adaptive strategies and contributing to the conservation of urban biodiversity.Methods:Our study examined woody plants within 120 sample plots across 15 remnant forest patches in Guiyang,China.We constructed leaf trait networks (LTNs) based on 26 anatomical,structural,and compositional leaf traits and assessed the effects of the spatiotemporal dynamics of urban expansion on these LTNs.Results and conclusions:Our results indicate that shrubs within these patches have greater average path lengths and diameters than trees.With increasing urban expansion intensity,we observed a rise in the edge density of the LTN-shrubs.Additionally,modularity within the networks of shrubs decreased as road density and urban expansion intensity increased,and increases in the average path length and average clustering coefficient for shrubs were observed with a rise in the composite terrain complexity index.Notably,patches subjected to‘leapfrog’expansion exhibited greater average patch length and diameter than those experiencing edge growth.Stomatal traits were found to have high degree centrality within these networks,signifying their substantial contribution to multiple functions.In urban remnant forests,shrubs bolster their resilience to variable environmental pressures by augmenting the complexity of their leaf trait networks. 展开更多
关键词 Urban remnant forest patch Woody plant Leaf trait network Plant adaptation strategy Spatiotemporal urban expansion
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Observing eddy dye patches induced by shear instabilities in the surf zone on a plane beach
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作者 Chunping Ren Nannan Fu +2 位作者 Chong Yu Yuchuan Bai Kezhao Fang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期15-29,共15页
The effects of surf zone eddy generated by alongshore currents on the deformation and transport of dye are still poorly understood,and related tracer release experiments are lacking.Therefore,a tracer release laborato... The effects of surf zone eddy generated by alongshore currents on the deformation and transport of dye are still poorly understood,and related tracer release experiments are lacking.Therefore,a tracer release laboratory experiment was conducted under monochromatic,unidirectional incident waves with a large incident angle(30°)on a plane beach with a 1:100 slope in a large wave basin.A charge-coupled device suspended above the basin recorded the dye patch image.The evolution of eddy dye patch was observed and the transport and diffusion were analyzed based on the collected images.Subsequently,a linear instability numerical model was adopted to calculate the perturbation velocity field at the initial stage.The observation and image processing results show that surf zone eddy patches occurred and were separated from the original dye patches.Our numerical analysis results demonstrate that the structure of the perturbation velocity field is consistent with the experimental observations,and that the ejection of eddy patches shoreward or offshore may be ascribed to the double vortex. 展开更多
关键词 surf zone tracer release experiment evolution of eddy patch shear instability of alongshore currents
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一种基于图像patches分割的自监督生成对抗模型
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作者 陈才扣 高俊 《软件导刊》 2023年第4期142-147,共6页
近年来,通过将基于角度旋转的自监督模型引入到生成对抗网络中,一定程度上缓解了生成对抗模型稳定性不足与模式坍塌问题。但是,这种自监督模型基于全局信息对比,缺乏局部相关性,模型特征提取能力不足,导致生成图片的全局相似度较高而像... 近年来,通过将基于角度旋转的自监督模型引入到生成对抗网络中,一定程度上缓解了生成对抗模型稳定性不足与模式坍塌问题。但是,这种自监督模型基于全局信息对比,缺乏局部相关性,模型特征提取能力不足,导致生成图片的全局相似度较高而像素精度不足。因此,提出一种新型自监督生成对抗模型,将图像块(patches)引入到传统的角度旋转自监督模型中,通过对图像进行分块,将局部图像与整体图像作为输入,在旋转角度判别器的基础上新增位置判别器,在提高模型全局相似性的同时,增强了局部特征相关性。在CIFAR-10与STL-10数据集上进行测试,实验结果表明,基于图像patches分割的自监督生成模型比角度旋转自监督模型的效果更好。 展开更多
关键词 深度学习 自监督学习 生成对抗模型 patches
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Divergent responses of Picea crassifolia Kom.in different forest patches to climate change in the northeastern Tibetan Plateau
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作者 Zhongtong Peng Qifeng Mo +5 位作者 Liangjun Zhu Qingao Lu Jiaqing Cai Mingming Guo Kun Xu Yuandong Zhang 《Forest Ecosystems》 SCIE CSCD 2023年第6期752-762,共11页
Global climate changes have significantly affected tree growth and forest structures and functions in some arid and semi-arid regions,which are becoming warmer and wetter.Due to natural factors such as climate and ter... Global climate changes have significantly affected tree growth and forest structures and functions in some arid and semi-arid regions,which are becoming warmer and wetter.Due to natural factors such as climate and terrain,some tree species may form different forest patches at the edges of their distribution areas.However,how forest patches of various sizes respond to climate change is unclear.In this study,we collected 203 tree cores from six different sizes of forest patches at the edge of the distribution area of Picea crassifolia Kom.in the northeast Tibetan Plateau.And we used the dendrochronology method to study the response of tree growth and resilience in different forest patches to climate change from 1961 to 2020.We simultaneously measured the contents of nonstructural carbohydrates(NSC),total nitrogen and total phosphorus of tree needles.Our results showed that the growth of trees in small-and medium-size forest patches(0.8–18.6 ha)has increased significantly.The early growing season(May–July)minimum temperature was the most important climate factor driving the growth of small-and medium-sized patch trees.The early growing season maximum temperature was the most important climate factor that inhibited the growth of trees in the largest patches(362.8 ha).The growth of individual trees in medium forest patches was better and the correlation with annual minimum temperature,maximum temperature,precipitation,actual evapotranspiration,and palmer drought severity index was stronger.The higher NSC content,stronger photosynthesis,and higher nitrogen utilization efficiency in leaves might be one of the reasons for the better growth of trees in moderate forest patches.In extreme drought years,as the forest patch area increased,the overall trend of tree growth resistance showed a unimodal pattern,with the highest at a forest patch area of 7.1 ha,while the overall trend of tree growth recovery was opposite.Therefore,we should strengthen the management of trees in large forest patches to cope with climate change. 展开更多
关键词 Climate change Picea crassifolia Kom Forest patches Tree growth RESILIENCE
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利用GPS对磁暴期间极区TEC变化与极区碎片(Polar Patches)的研究 被引量:13
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作者 孟泱 王泽民 +1 位作者 鄂栋臣 蔡红涛 《地球物理学报》 SCIE EI CSCD 北大核心 2008年第1期17-24,共8页
利用2004年11月6-10日磁暴发生期间南极区域内的中国中山站GPS常年跟踪站(ZHON)和国际GPS服务站(CAS1,MCM4,SYOG,MAW1)的GPS观测数据,计算了可观测卫星传播路径上的TEC和ROT值,进而依据TEC的波动频率和幅度推估出极区碎片的个数,分... 利用2004年11月6-10日磁暴发生期间南极区域内的中国中山站GPS常年跟踪站(ZHON)和国际GPS服务站(CAS1,MCM4,SYOG,MAW1)的GPS观测数据,计算了可观测卫星传播路径上的TEC和ROT值,进而依据TEC的波动频率和幅度推估出极区碎片的个数,分析了极区磁暴期间电离层响应及其极区碎片特性.最终所得TEC和ROT结果与极区地磁场Dst和Kp指数信息相吻合,如实地反映了磁暴事件和极区碎片的出现.本文所做工作在国内尚未开展,因此所用方法和结论为将来这一方向的研究提供了一定的参考. 展开更多
关键词 磁暴 极区碎片(polar patches) GPS TEC ROT
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弓形虫复合粘膜疫苗滴鼻免疫小鼠诱导的Peyer's patches持续性细胞免疫应答 被引量:2
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作者 孟晓丽 殷国荣 +3 位作者 张建红 刘红丽 申金雁 李珀 《中国病原生物学杂志》 CSCD 2008年第1期27-30,共4页
目的以可溶性速殖子抗原(soluble tachyzoite antigen,STAg)和霍乱毒素(choleratoxin,CT)佐剂制备的弓形虫复合粘膜疫苗滴鼻免疫小鼠,观察肠粘膜诱导部位Peyer’s patches(PP)的细胞免疫应答及持续时间,探讨其免疫机制。方法B... 目的以可溶性速殖子抗原(soluble tachyzoite antigen,STAg)和霍乱毒素(choleratoxin,CT)佐剂制备的弓形虫复合粘膜疫苗滴鼻免疫小鼠,观察肠粘膜诱导部位Peyer’s patches(PP)的细胞免疫应答及持续时间,探讨其免疫机制。方法BALB/c小鼠96只,随机分为实验组和对照组,实验组以STAg(20μg/只)为抗原,CT(1/μg/只)为佐剂滴鼻免疫,对照组PBS滴鼻。滴鼻2次(间隔2周)后,每组6只小鼠分别于第1、2、3、4、6、8、10、12周处死。计数PP个数,制备PP淋巴细胞悬液,计数并涂片;免疫细胞化学法检测CD4^+、CD8^+T细胞亚群。结果实验期间两组小鼠PP数目均无明显变化;实验组免疫后PP淋巴细胞数量明显增生,第2周达高峰,第1、2、3周显著高于对照组(P〈0.05),其中以CD4^+T细胞增生为主,第1周~第8周高于对照组(P〈0.01),CD8^+T细胞第1周~第4周显著增高(P〈0.01),CD4^+/CD8^+比值无显著变化(P〉0.05)。结论弓形虫复合粘膜疫苗滴鼻免疫BALB/c小鼠可有效诱导肠PP部位持续性的免疫应答,从而激活肠粘膜效应部位淋巴细胞的抗弓形虫感染作用。 展开更多
关键词 弓形虫 粘膜疫苗 滴鼻免疫 可溶性速殖子抗原 霍乱毒素 Peyer’s patches
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Epidural Blood Patches Performed with Miethke Sensor Reservoir for Continuous Intracranial Pressure Monitoring
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作者 Nishant J. Modi Prem P. Darji +1 位作者 Yan C. Magram Iman A. Rabizadeh 《Case Reports in Clinical Medicine》 2023年第1期9-13,共5页
An epidural blood patch (EBP) is a procedure performed by injecting autologous blood into a patient’s epidural space, usually at the site of a suspected CSF leak. It is typically performed in patients with characteri... An epidural blood patch (EBP) is a procedure performed by injecting autologous blood into a patient’s epidural space, usually at the site of a suspected CSF leak. It is typically performed in patients with characteristic postural headaches due to low intracranial pressure. We report a case of a young female with an implanted Miethke Sensor Reservoir, which was used for continuous intracranial pressure (ICP) monitoring during a two-level epidural blood patch. ICP increased only with thoracic injection, suggesting thoracic EBP may have greater efficacy than lumbar EBP in treating SIH and PDPH when the site of CSF leak is unknown. 展开更多
关键词 Epidural Blood Patch Intracranial Pressure Monitoring Spontaneous Intracranial Hypotension Post Dural Puncture Headache Pain Management
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Zingiber cassumunar blended patches for skin application:Formulation,physicochemical properties,and in vitro studies 被引量:1
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作者 Jirapornchai Suksaeree Laksana Charoenchai +4 位作者 Fameera Madaka Chaowalit Monton Apirak Sakunpak Tossaton Charoonratana Wiwat Pichayakorn 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2015年第4期341-349,共9页
Our work was to study the preparation,physicochemical characterization,and in vitro characteristic of Zingiber cassumunar blended patches.The Z.cassumunar blended patches incorporating Z.cassumunar Roxb.also known as ... Our work was to study the preparation,physicochemical characterization,and in vitro characteristic of Zingiber cassumunar blended patches.The Z.cassumunar blended patches incorporating Z.cassumunar Roxb.also known as Plai were prepared from chitosan and polyvinyl alcohol with glycerin as plasticizer.They were prepared by adding all ingredients in a beaker and homogeneously mixing them.Then,they were transferred into Petri-dish and dried in hot air oven.The hydrophilic nature of the Z.cassumunar blended patches was confirmed by the moisture uptake,swelling ratio,erosion,and porosity values.The FTIR,DSC,XRD,and SEM studies showed revealed blended patches with amorphous region that was homogeneously smooth and compact in both surface and cross section dimensions.They exhibited controlled the release behavior of(E)-4-(30,40-dimethoxyphenyl)but-3-en-lol(compound D)that is the main active compound in Z.cassumunar for anti-inflammation activity.However,in in vitro skin permeation study,the compound D was accumulated in newborn pig skin more than in the receptor medium.Thus,the blended patches showed the suitable entrapment and controlled release of compound D.Accordingly,we have demonstrated that such chitosan and polyvinyl alcohol formulated patches might be developed for medical use. 展开更多
关键词 CHITOSAN Polyvinyl alcohol Z.cassumunar patches Blended patches Skin application
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Formulation of unidirectional release buccal patches of carbamazepine and study of permeation through porcine buccal mucosa 被引量:1
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作者 Parthasarathy Govindasamy Bhaskar Reddy Kesavan Jayaveera Korlakunta Narasimha 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第12期995-1002,共8页
Objective:To achieve transbuccal release of carbamazepine by loading in unidirectional release mucoadhesive buccal patches.Methods:Buccal patches of carbamazepine with unidirectional drug release were prepared using h... Objective:To achieve transbuccal release of carbamazepine by loading in unidirectional release mucoadhesive buccal patches.Methods:Buccal patches of carbamazepine with unidirectional drug release were prepared using hydroxypropyl methyl cellulose,polyvinyl alcohol,polyvinyl pyrrolidone and ethyl cellulose by solvent casting method.Water impermeable backing layer(Pidilite?Biaxially-oriented polypropylene film)of patches provided unidirectional drug release.They were evaluated for thickness,mass uniformity,surface pH and folding endurance.Six formulations FA2,FA8,FA10,FBI,FB14 and FB16(folding endurance above 250)were evaluated further for swelling studies,ex vivo mucoadhesive strength,ex vivo mucoadhesion time,in vitro drug release,ex vivo permeation,accelerated stability studies and FTIR and XRD spectral studies.Results:The ex vivo mucoadhesion time of patches ranged between 109 min(FA10)to 126 min(FB14).The ex vivo mucoadhesive force was in the range of 0.278 lo 0.479 kg/m/s.The in vitro drug release studies revealed that formulation FA8 released 84%and FB16 released 99.01%of drug in140 min.Conclusions:The prepared unidirectional buccal patches of carbamazepine provided a maximum drug release within specified mucoadhesion period and it indicates a potential alternative drug delivery system for systemic denvery of carbamazepine. 展开更多
关键词 BUCCAL patches CARBAMAZEPINE MUCOADHESION Biaxially-oriented polypropylene films PORCINE BUCCAL MUCOSA
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Infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems of Inner Mongolia, China 被引量:1
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作者 ZHANG Si-yi LI Xiao-yan +1 位作者 PENG Hai-ying ZHANG Zhi-hua 《地球环境学报》 2012年第6期1117-1125,共9页
Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patch... Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems.The dye coverage,uniform infiltration depth,maximum infiltration depth,total stained area and heterogeneous infiltration stained area were measured by two indices,the maximum infiltration depth index(MIDI)and heterogeneous infiltration index(HII),which were calculated by processing dye-stained photos.The MIDI and HII of soil under shrubs were 1.41±0.14 and 0.29±0.068,respectively,and larger than those of grass soil,1.26±0.14 and0.20±0.076.Using the MIDI,HII,field soil moisture and rainfall data,the infiltration depth and heterogeneous infiltration amount for 26 nature rainfall events were calculated.The results imply that water can infiltrate to a deeper layer beneath shrub canopy than beneath grass patches and that more water infiltration occurs beneath shrub canopy than beneath grass patches.These results are of prime importance for arid and semiarid ecosystems with a limited water supply due to high evaporation and low precipitation. 展开更多
关键词 Infiltration pattern dye-tracing SHRUB grass patches typical steppe ecosystems
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Aboveground Woody Biomass, Carbon Stocks Potential in Selected Tropical Forest Patches of Tripura, Northeast India 被引量:1
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作者 Koushik Majumdar Bal Krishan Choudhary Badal Kumar Datta 《Open Journal of Ecology》 2016年第10期598-612,共15页
To estimate woody plant biomass stocks in different patches of forest ecosystems, total 20, 500 × 10 m (0.5 ha) sized line transects were laid in a protected area of Tripura, Northeast India. Overall, 9160 indivi... To estimate woody plant biomass stocks in different patches of forest ecosystems, total 20, 500 × 10 m (0.5 ha) sized line transects were laid in a protected area of Tripura, Northeast India. Overall, 9160 individuals were measured at ≥10 cm diameter at breast height (dbh) in 10 ha sampled area. Estimation of biomass suggested that highest coefficient for allometric relationships between density and biomass in 10 dbh classes was observed in bamboo brakes (R<sup>2</sup> = 0.90) than lowest for semi evergreen patch (R<sup>2</sup> = 0.48). The stock of carbon (C) was differ significantly along the forest patches (F = 7.01, df = 3.19;p < 0.01). Most of biomass stock (69.38%) was accumulated in lower dbh class (<30 cm) and only 23% of biomass was estimated at higher dbh classes (> 70 cm). Range of biomass stock (37.85 - 85.58 Mg ha<sup>-</sup><sup>1</sup>) was low, compared to other tropical forest ecosystems in India, which implies that the proper management is required to monitor regional ecosystem C pool. 展开更多
关键词 Woody Biomass Potential Carbon Storage Tropical Forest patches Tripura
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Influences of pika and simulated grazing disturbances on bare patches of alpine meadow in the Yellow River Source Zone
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作者 LI Jie-xia LI Xi-lai +3 位作者 GAO Jay SHI Yan MA Ge-liang Ka-zhao-cai-rang 《Journal of Mountain Science》 SCIE CSCD 2021年第5期1307-1320,共14页
Bare patches in alpine meadow are the main manifestation of its degradation.The change of bare patches in an alpine meadow in the Yellow River Source Zone during 2018-2019 was studied in relation to the disturbances c... Bare patches in alpine meadow are the main manifestation of its degradation.The change of bare patches in an alpine meadow in the Yellow River Source Zone during 2018-2019 was studied in relation to the disturbances caused by plateau pika(Ochotona curzoniae)population and simulated grazing via artificial mowing both independently and interactively.The disturbance was set at three levels of high,medium and no disturbance(control group).Bare patches were mapped by from unmanned aerial vehicle(UAV)images with fine resolution of 1 cm obtained in August 2018 and August 2019 in ArcGIS.The results showed that the total area of bare patches decreased by 112.05 m2 in sub-plots devoid of pika disturbance but increased by 126.37 m2 in other subplots.The highest rate of increase is 89.02%.The individual effect of pika exceeds the joint effect of pika and mowing disturbances.The sole effect of mowing is lower than the joint effect of pika disturbance and intensive mowing,but higher than the joint influence of pika disturbance and moderate mowing.Strong pika disturbance(14 per sub-plot)caused the influence of mowing from moderate to intensive to increase by five-fold.The area of bare patches treated with moderate mowing and no pika disturbance decreased at the highest pace(-37.22%).Intensive mowing and medium density pikas(100 pikas/ha)are considered the thresholds at which the bare patches start to expand.Even if the meadow is mowed at the medium and high intensity,the area of bare patches can be significantly reduced if plateau pika population is controlled to a low level.ANOVA analysis and longterm macro-scale satellite-derived results reveal that pika disturbance is more important in causing the bare patches to change than simulated grazing.Therefore,it is more important to control the number of pikas than to reduce grazing intensity to prevent the expansion of bare patches in the degraded alpine meadow in the study area. 展开更多
关键词 Bare patches simulated grazing Pika disturbance Interactive influence UAV Yellow River Source Zone
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The Dual-Polarized Staggered Stacked Patches Antenna
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作者 Xinyu Cao Jinling Zhang +1 位作者 Hongzhen Yang Hourong Li 《China Communications》 SCIE CSCD 2021年第12期208-218,共11页
A new dual-polarized staggered and stacked patches antenna with wide impedance band-width and high isolation is proposed.The antenna consists of two groups of radiation patches,in 7 layers,and uses the orthogonal adja... A new dual-polarized staggered and stacked patches antenna with wide impedance band-width and high isolation is proposed.The antenna consists of two groups of radiation patches,in 7 layers,and uses the orthogonal adjacent coupling structure on staggered layer to excite a pair of linear polarization modes.Thanks to the staggered feeder mode,it has increased the isolation performance be-tween ports and compressed the transverse size of the antenna.As a result of the combination of staggered stack-up between the patches and the stepped gradient shape of the main radiating patches,it has effectively expanded the impedance bandwidth of the antenna.The proposed antenna is simulated,fabricated and measured.The staggered feeding structure effectively reduces the cross-sectional area of the antenna,and greatly improves the isolation between feeding ports.The measurement results show that the impedance bandwidths for vertical and horizontal polarization modes are 40.2%(638-960 MHz)and 40.0%(645-968 MHz)respectively when the return loss is lower than-10 dB,and the isolation between feeding ports is better than-30 dB.Meanwhile,the antenna has a stable and symmetrical radiation pattern across the working band,therefore making it suitable to be used as antenna and antenna array element of mobile wireless communication base stations. 展开更多
关键词 staggered stacked patches wide impedance bandwidth high isolation
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The Influence of HIF-1α Expression on Apoptosis and Number of T Lymphocyte in Peyer’s Patches after Burn with Delayed Fluid Resuscitation in Rats at Plateau
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作者 Cheng Zhang Yi Liu +1 位作者 Ming Ma Shifan Zhang 《Surgical Science》 2016年第9期390-399,共10页
Objective: To research the expression of hypoxia inducible factor-1 alpha (HIF-1 alpha) on the apoptosis and number of T lymphocyte in Peyer’s patches after severe burn on plateau in rats. Methods: Wistar rats (n = 1... Objective: To research the expression of hypoxia inducible factor-1 alpha (HIF-1 alpha) on the apoptosis and number of T lymphocyte in Peyer’s patches after severe burn on plateau in rats. Methods: Wistar rats (n = 130) were subjected to deep thickness burn injury (30% TBSA, III degree), at two different altitudes. 60 of them were given delayed fluid resuscitation (DFR, n = 30 at each altitude) 6 h after burn at different altitude;60 of them were carried out immediate fluid resuscitation (IFR, n = 30 at each altitude);10 rats were subjected to 37°C warm water as sham burn (SG, n = 10). The Peyer’s patches were harvested from the ileum of rats at different time point after burn respectively. The expression of HIF-1 alpha, CD3(+) and the apoptosis and number of T lymphocyte in Peyer’s patches were detected by tissue microarray technology and immunohistochemistry. Results: The apoptosis was higher in DFR group than that in IFR group. The increase in HIF-1 alpha expression was observed mainly on cell nucleus in T lymphocytes. The expression levels of HIF-1 alpha in Peyer’s patches were much higher in DFR group and IFR group than those in SG, and they were higher at high altitude (3848 metres) than those at lower altitude (1517 metres), and also higher in DFR group compared with IFR group (all P < 0.05). The expression levels of CD3<sup>+</sup> in Peyer’s patches were much lower in DFR group and IFR group than those in sham group, and the lowest value appeared at 12 hours after burn (all P < 0.05). Conclusion: High expression of HIF-1 alpha may induce the apoptosis of T lymphocytes in Peyer’s patches after severe burn with delayed fluid resuscitation in rats at plateau. 展开更多
关键词 Delayed Fluid Resuscitation Peyer’s patches APOPTOSIS HIF-1Α BURN PLATEAU
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Utility of cooling patches to prevent hand-foot syndrome caused by pegylated liposomal doxorubicin in breast cancer patients 被引量:6
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作者 Yan-Fu Zheng Xin Fu +2 位作者 Xiao-Xu Wang Xiao-Jing Sun Xiao-Dan He 《World Journal of Clinical Cases》 SCIE 2021年第33期10075-10087,共13页
BACKGROUND Pegylated liposomal doxorubicin(PLD)uses the hydrophilic layer of liposomes to reach the sweat on the skin surface or accumulate in the sweat glands,producing toxic free radicals and oxidative damage,result... BACKGROUND Pegylated liposomal doxorubicin(PLD)uses the hydrophilic layer of liposomes to reach the sweat on the skin surface or accumulate in the sweat glands,producing toxic free radicals and oxidative damage,resulting in hand-foot syndrome(HFS).Regional cooling can induce vasoconstriction to reduce the release of drugs in the limbs and reduce the accumulation of drugs in sweat glands;thus,decreasing the incidence and severity of HFS.AIM To study the efficacy of cooling patches to prevent HFS caused by PLD in the short-term.METHODS This is a retrospective cohort study.Female breast cancer patients(n=101)who were treated with PLD in two breast wards at our department from February 2020 to February 2021 were enrolled in the study and were randomly divided into the cooling group(51 patients)and the control group(50 patients).Patients in the control group only received routine care,while the patients in the cooling group applied cooling patches,based on routine care,to the palm and back of the hands 15 min before chemotherapy infusion for 10 h.All patients took a corresponding dose of dexamethasone orally one day before chemotherapy,on the day of chemotherapy,and one day after chemotherapy.SPSS23.0 version was used to analyze the data in this study.The occurrence and severity of HFS was analyzed by the Mann-Whitney U test,and scores were analyzed by the Student’s t test or Wilcoxon rank-sum test.A P value<0.05 was regarded as statistically significant.RESULTS In this study,neither group of patients developed Grade 3 HFS.In the control group,the incidence of Grade 1 HFS and Grade 2 HFS was 38%and 2%,respectively.However,in the cooling group,only one person developed Grade 1 HFS(2%),and none of the patients developed Grade 2 HFS.These findings showed that cooling patches can effectively reduce the frequency and severity of HFS(P<0.0001)in the short-term.Before the fourth chemotherapy cycle,although general self-efficacy scale scores in the cooling group were low,they were still significantly higher than those in the control group(17.22±5.16 vs 19.63±6.42,P=0.041).Compared with the control group,the mean Hand-Foot Skin Reaction and Quality of Life Questionnaire score in the cooling group was significantly lower(18.08±7.01 vs 14.20±7.39,P=0.008).CONCLUSION Cooling patches can effectively reduce the frequency and severity of HFS caused by PLD in the short-term.In addition,it may help delay the decline in patients’self-efficacy. 展开更多
关键词 The cooling patch Hand-foot syndrome Pegylated liposomal doxorubicin Breast cancer Self efficacy Quality of life
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Domain Decomposition for Wavelet Single Layer on Geometries with Patches 被引量:3
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作者 Maharavo Randrianarivony 《Applied Mathematics》 2016年第15期1798-1823,共27页
We focus on the single layer formulation which provides an integral equation of the first kind that is very badly conditioned. The condition number of the unpreconditioned system increases exponentially with the multi... We focus on the single layer formulation which provides an integral equation of the first kind that is very badly conditioned. The condition number of the unpreconditioned system increases exponentially with the multiscale levels. A remedy utilizing overlapping domain decompositions applied to the Boundary Element Method by means of wavelets is examined. The width of the overlapping of the subdomains plays an important role in the estimation of the eigenvalues as well as the condition number of the additive domain decomposition operator. We examine the convergence analysis of the domain decomposition method which depends on the wavelet levels and on the size of the subdomain overlaps. Our theoretical results related to the additive Schwarz method are corroborated by numerical outputs. 展开更多
关键词 WAVELET Single Layer PATCH Domain Decomposition Convergence Graph Partitioning Condition Number
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Analytical Polarizable Continuum Model for Wavelets on NURBS Patches 被引量:1
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作者 Maharavo Randrianarivony 《Applied Mathematics》 2017年第8期1045-1073,共29页
This article concerns the application of wavelet techniques on molecular surfaces constituted of four-sided patches. The Polarizable Continuum Model, which is governed by the Poisson-Boltzmann equation, is treated by ... This article concerns the application of wavelet techniques on molecular surfaces constituted of four-sided patches. The Polarizable Continuum Model, which is governed by the Poisson-Boltzmann equation, is treated by means of boundary integral equations. The media inside and outside the molecular surface consist respectively of the solute and the solvent. For a given electrically charged molecule, the principal unknown is the electrostatic solvation energy when the permittivity is specified. The wavelet basis functions are constructed on the unit square which are subsequently mapped onto the patches that are assumed to be isotropically shaped and to admit similar surface areas. The initial transmission problem is recast as an integral equation in term of both the single and the double layers. Domain decomposition preconditioner serves as acceleration of the linear solver of the single layer which is badly conditioned. 展开更多
关键词 Polarizable CONTINUUM Model Wavelet POISSON-BOLTZMANN PATCH Electrostatic SOLVATION Energy
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Multiwavelet Boundary Element Method for Cavities Admitting Many NURBS Patches 被引量:2
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作者 Maharavo Randrianarivony 《Modeling and Numerical Simulation of Material Science》 2016年第4期69-93,共25页
We consider the modeling and simulation by means of multiwavelets on many patches. Our focus is on molecular surfaces which are represented in the form of Solvent Excluded Surfaces that are featured by smooth blending... We consider the modeling and simulation by means of multiwavelets on many patches. Our focus is on molecular surfaces which are represented in the form of Solvent Excluded Surfaces that are featured by smooth blendings between the constituting atoms. The wavelet bases are constructed on the unit square which maps bijectively onto the patches embedded in the space. The cavity which designates the surface bounding a molecular model is acquired from the nuclei coordinates and the Van-der-Waals radii. We use multi-wavelets for which the wavelet basis functions are organized hierarchically on several levels. Our assembly of the linear system is accomplished by using a hierarchical tree which enables the treatment of large molecules admitting thousands of patches. Along with the patch construction, some wavelet simulation outcomes which are applied to realistic patches are reported. 展开更多
关键词 Wavelet Patch NURBS Connolly Modeling
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