Subjects: Geosciences >> Geography submitted time 2024-03-01 Cooperative journals: 《干旱区研究》
Abstract： Vegetation carbon use efficiency (CUE) can objectively reflect the efficiency of vegetation insequestering atmospheric carbon and the response of vegetation to climate change. Using MOD17, land use, andmeteorological data, this study applied methods, such as the Hurst exponent, correlation analysis, and sensitivityanalysis to explore the spatiotemporal variability of vegetation CUE and its sensitivity to climate factors in theShaanxi section of the Yellow River Basin from 2001 to 2021. The results showed that (1) From 2001 to 2021,the gross primary productivity, net primary productivity (NPP), and vegetation CUE in the Shaanxi section of theYellow River Basin exhibited an increasing trend, with an average CUE value of 0.51. (2) The study area wasonly 14.21% of the region, exhibiting a decreasing trend. The high-value areas of vegetation CUE are primarilyconcentrated in the windbreak and sand-fixation areas and the Grain for Green Project areas of northern Shaanxi.The areas where vegetation CUE indicated a decreasing trend accounted for 59.96%, most of which transitionedfrom an increasing trend to a decreasing trend. (3) Overall, temperature and precipitation correlated negativelywith vegetation CUE, but the relationship with precipitation is more significant. Regions with positivecorrelations with temperature and precipitation are distributed in northern Shaanxi’s windbreak and sand-fixationareas. Sensitivity analysis of temperature and precipitation showed that the threshold values were 10 °C and 500mm, respectively. When the temperature is below 10 °C and the precipitation is below 500 mm, the vegetationCUE increases with increasing temperature and precipitation. The relationship between vegetation CUE andclimate factors is more significant and sensitive in arid areas, such as the conversion of farmland to forests andwindbreak and sand-fixation areas in northern Shaanxi.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： In order to better participate in the international digital development, it is crucial to investigate the internal digital governance pattern of various countries and clarify their internal generation logic on the basis of recognizing the current situation. This work makes a comparative study of the internal digital governance patterns in China, the United States and European Union from the perspective of digital ecology, attempts to clarify their respective digital ecological development models, and analyzes the relationship between the development models and their digital regulation systems. The study found that the United States has formed a development model taking the lead in all aspects and a regulation system centered on encouraging innovation. The diversified development model of EU member countries has affected the EU to form a regulation system centered on market construction. China’s development model shows the characteristics of being application#2;driven, and the regulation system takes development and security as the dual core. Based on this, the study puts forward suggestions on how to optimize and adjust China’s digital regulation system, as well as transform and upgrade its digital ecological development model.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： To promote the high-quality development of new-type think tanks with Chinese characteristics, better serve the national governance system, and advance the modernization of China’s system and capacity of governance, it is necessary to improve the ability of think tanks to organize and manage tasks, and it is important to explore and establish project management paradigms that adapt to the characteristics of think tank research. Under the double helix structure theory, this study deeply analyzes the characteristics of think tank research and project management from the perspective of a professional think tank management team, based on understanding of think tank research characteristics and project management experience. This study proposes suggestions to improve the organization and management capacities of think tanks.
Subjects: Psychology >> Social Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： In recent years, researchers have begun to study the causes of depression from the perspective of social identity (The Social Identity Approach). These studies suggested two broad categories: single-multiple and static-dynamic. Single-multiple refers to whether researchers focus on the degree of individual identification with a particular group or the number of groups that individuals identify with when examining social identity. Static-dynamic focuses on an individual's identity at a specific time or an identity change before and after life transitions (such as further education, immigration, and others). Therefore, the investigation of social identity can be divided into four situations: static single (identity degree), dynamic single (identity importance), static multiple (identity group number), and dynamic multiple (identity change). They had a positive effect on depression overall. However, the importance of identity in stigmatized groups and its loss in changes worsen depression. Regarding mediating mechanisms, researchers believe that social identity can alleviate depression by satisfying needs. Furthermore, it can reduce it by changing individuals' cognition and behavior. These mediating factors can be divided into three aspects: need, cognition, and behavior.Regarding theoretical explanation, Haslam et al. (2009) were the first to propose using the social identity perspective to explain mental health phenomena explicitly. They regarded this field as an important research trend. Four theories have been proposed to explain the relationship between social identity and depression. First, the Social Cure proposes that the psychological resources associated with group identity have a protective effect on individual mental health. Second, the Social Identity Model of Depression is the first to define it from a social identity perspective, proposing four key psychological resources (meaning, social influence, social support, and belonging) for depression. Third, the Social Identity Model of Identity Change shifts to a dynamic perspective, arguing that social identity continuity and gain pathway plays an essential role in life change. Finally, the hierarchical interaction model emphasizes that social identity has different levels, and these have various underlying psychological mechanisms.Future research should be carried out from three aspects. (1) In the deep influence mechanism of social identity on depression, we should examine whether it increases an individual's interpersonal support and sense of belonging. However, more importantly, we should examine whether the meaning (target, significance, and values) and influence (such as group norms) are beneficial to physical and mental health. When the group's meaning and influence are detrimental to an individual's physical and mental health, social support and a sense of belonging can increase this detrimental effect, leading to increased depression. (2) Use empirical research to test the moderating factors proposed by previous theoretical explanations from three aspects: individual, group, and intergroup. Examples include group type (category/interaction group), normative content (positive/negative), identity compatibility, and the role of group performance. (3) Construct an agency-communion model of social identity affecting depression. This model could simultaneously explain the four pathways of social identity's influence on depression, simplifying psychological resources into agency (meaning and social influence) and communion (social support and sense of belonging). Their mediating effects correspond one-to-one with the four situations of social identity. The model proposes the moderating role of the content of agency psychological resources, such as the meaning and social influence are detrimental to individual physical and mental health, the performance of group "failures," and the conflict of multiple identities.
submitted time 2023-03-25 Cooperative journals: 《心理科学进展》
Abstract： In recent years, researchers have begun to study the causes of depression from the perspective of social identity (The Social Identity Approach). These studies suggested two broad categories: single-multiple and static-dynamic. Single-multiple refers to whether researchers focus on the degree of individual identification with a particular group or the number of groups that individuals identify with when examining social identity. Static-dynamic focuses on an individual's identity at a specific time or an identity change before and after life transitions (such as further education, immigration, and others). Therefore, the investigation of social identity can be divided into four situations: static single (identity degree), dynamic single (identity importance), static multiple (identity group number), and dynamic multiple (identity change). They had a positive effect on depression overall. However, the importance of identity in stigmatized groups and its loss in changes worsen depression. Regarding mediating mechanisms, researchers believe that social identity can alleviate depression by satisfying needs. Furthermore, it can reduce it by changing individuals' cognition and behavior. These mediating factors can be divided into three aspects: need, cognition, and behavior.Regarding theoretical explanation, Haslam et al. (2009) were the first to propose using the social identity perspective to explain mental health phenomena explicitly. They regarded this field as an important research trend. Four theories have been proposed to explain the relationship between social identity and depression. First, the Social Cure proposes that the psychological resources associated with group identity have a protective effect on individual mental health. Second, the Social Identity Model of Depression is the first to define it from a social identity perspective, proposing four key psychological resources (meaning, social influence, social support, and belonging) for depression. Third, the Social Identity Model of Identity Change shifts to a dynamic perspective, arguing that social identity continuity and gain pathway plays an essential role in life change. Finally, the hierarchical interaction model emphasizes that social identity has different levels, and these have various underlying psychological mechanisms.Future research should be carried out from three aspects. (1) In the deep influence mechanism of social identity on depression, we should examine whether it increases an individual's interpersonal support and sense of belonging. However, more importantly, we should examine whether the meaning (target, significance, and values) and influence (such as group norms) are beneficial to physical and mental health. When the group's meaning and influence are detrimental to an individual's physical and mental health, social support and a sense of belonging can increase this detrimental effect, leading to increased depression. (2) Use empirical research to test the moderating factors proposed by previous theoretical explanations from three aspects: individual, group, and intergroup. Examples include group type (category/interaction group), normative content (positive/negative), identity compatibility, and the role of group performance. (3) Construct an agency-communion model of social identity affecting depression. This model could simultaneously explain the four pathways of social identity's influence on depression, simplifying psychological resources into agency (meaning and social influence) and communion (social support and sense of belonging). Their mediating effects correspond one-to-one with the four situations of social identity. The model proposes the moderating role of the content of agency psychological resources, such as the meaning and social influence are detrimental to individual physical and mental health, the performance of group "failures," and the conflict of multiple identities.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-18 Cooperative journals: 《材料研究学报》
Abstract： Luminescent phosphors GdVO4: Eu3 + was prepared in solutions with different pH values by hydrothermal synthesis route using Gd2O3, NH4VO3 and Eu2O3 as precursors, and cetyl trimethyl ammonium bromide (CTAB) as surfactant. The synthesized products were characterized in terms of morphology, structure and luminescent performance by means of XRD, SEM, TEM, and PL. The results show that in an acid solution with pH=1, the size of synthesized GdVO4: Eu3 + crystal grains is of micron scale; in a solution with pH=4 , their size shrinks to nano-scale; it turned out well-dispersed nano-flakes of about 50 nm in solution with pH=7; besides, in solution with pH=10, a certain amount of impurity Gd(OH)3 was detected by XRD for the synthesized GdVO4: Eu3+ crystal grains. On the other hand, the surfactant affected obviously the final morphology of the synthesized GdVO4: Eu3 + crystal grains in terms of changes in the crystal growth direction and the aggregation shape, correspondingly, the luminescent properties were affected by grain size and crystallinity. It turned out that square GdVO4: Eu3+ nano-crystals with well crystallinity represented the optimal emission performance. But it is noted that the aggregation effect may weaken the luminescent property of the products.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2020-09-28 Cooperative journals: 《计算机应用研究》
Abstract： In order to solve the problem that the residual network can not extract image information well and the segmentation effect is poor in semantic segmentation, this paper proposed a joint feature pyramid model (JFP) to integrate the output features of the residual network, and then further extract the features in combination with the atrous spatial pyramid pooling module (ASPP) . In the decoding part, this paper applied a simple decoding structure to recover the image size to complete the semantic segmentation This paper also used attention module as the auxiliary semantic segmentation network to assist the training of the neural network. This method trains the network in the Pascal VOC 2012 data set and the enhanced Pascal VOC 2012 data set respectively, and tests it on the verification set of Pascal VOC 2012. The average ratio of intersection and Union (Miou) is 78.55% and 80.14% respectively, which shows that proposed method has good semantic segmentation performance.
Subjects: Biology >> Botany >> Applied botany submitted time 2020-08-03 Cooperative journals: 《广西植物》
Abstract：牡丹干燥根皮自古以来就有入药的传统，尤其在中药和民族药中被广泛使用。为了阐明牡丹组植物在古籍中的记载情况和民族药中的利用现状，该文对中国八部经典医学古籍、37 部地方志和民族药传统知识进行整理，采用民族植物学编目方法，对牡丹组植物在古籍和民族药中的入药种类、地理分布、入药部位、炮制方法和功效等相关传统知识进行考证和分析研究。结果表明：古籍中记载的牡丹组植物种类被考证为 2 种，分别为牡丹（Paeonia suffruticosa）和滇牡丹（Paeonia delavayi），有 14 种炮制方法和 18 类功效；现有 9 个民族药使用 4 种牡丹组植物入药，为牡丹（P. suffruticosa）、滇牡丹（P. delavayi）、紫斑牡丹（Paeonia rockii）和四川牡丹（Paeonia decomposita）；在古籍和民族药中，牡丹（P. suffruticosa）入药的频率高于其他品种；古籍以根、丹皮和花入药与民族药记载相一致，入药部位以根和丹皮的使用频率最高。芍药属牡丹组植物有治疗糖尿病、高血压、肺炎、急性高烧、乌头中毒、急性阑尾炎、中风、癫疾、炭疽、安神和润泽肌肤等多种药用、保健和护肤功效，为该类植物资源的研发提供了知识原型和应用基础研究。
Subjects: Geosciences >> Geography submitted time 2020-06-12 Cooperative journals: 《干旱区地理》
Abstract： 本研究采用人为起火的方法，通过对比敦煌西湖荒漠湿地干扰区域和未干扰区域火后第一年芦苇群落特征的变化，探讨内陆荒漠湿地植被对火干扰的响应机制。了解火干扰对内陆荒漠湿地芦苇群落特征的影响。结果表明: 火干扰能够延长植物青绿期，促进了植被的个体发育；火干扰对草本层植被盖度、高度均有显著的负面影响，而对密度有显著的正面影响，对灌木层植被群落盖度、高度及密度均有正面影响，但影响不明显；火干扰后植物群落Shannon-Wiener多样性指数H′、Simpson多样性指数D和Simpson优势度指数C均减少，而Margalef物种丰富度指数Ma和Pielou均匀度指数J均增加；火干扰致使草本层植物群落多样性指数与研究区植物群落总体多样性指数变化趋势一致，致使灌木层物种H′、D和J指数均减少，而Ma和C指数均增加；火干扰致使植物群落地上总的生物量降低，主要使灌木层生物量降低，而使草本层生物量有所增加。
Subjects: Psychology >> Cognitive Psychology submitted time 2019-03-12
Abstract： Phonograms are comprised of a semantic radical and a phonetic radical. The semantic radical usually implies the meaning of a character, while the phonetic radical offers a phonetic clue for the pronunciation of a character. Prior research has indicated that semantic and phonetic radicals each play an important role in phonogram cognition. However, the way in which the 2 kinds of radicals combine to influence both phonogram recognition and the activation process remains a controversial topic. Neighborhood size is one of the most important characteristics of radicals. The differences induced by the neighborhood size of radicals are called neighborhood effects. Prior studies employed various methods to investigate the roles of semantic and phonetic radicals on phonogram recognition and discovered that phonetic radicals have an advantage in phonogram processing. They also found that the neighborhood size of semantic radicals regulated the relative contributions of semantic and phonetic radicals. However, most of these researchers investigated the roles of semantic and phonetic radicals respectively. Only a few investigators have focused on the comprehensive role of semantic and phonetic radicals in character processing. This study attempted to investigate the comprehensive effect of semantic and phonetic radicals on phonogram recognition. Participants’ brain responses were recorded using event-related brain potentials. Four types of characters were selected: HH (phonogram comprised of a high-frequency semantic radical and a high-frequency phonetic radical), HL (phonogram comprised of a high-frequency semantic radical and a low-frequency phonetic radical), LL (phonogram comprised of a low-frequency semantic radical and a low-frequency phonetic radical), and LH (phonogram comprised of a low-frequency semantic radical and a high-frequency phonetic radical). A lexical decision task was adopted; the frequency of the entire character and the number of strokes were equivalent for all groups. The results showed that, for characters with high-frequency semantic radicals (HH and HL), the characters with high-frequency phonetic radicals (HH) elicited a larger P200 waveform component than the characters with low-frequency phonetic radicals (HL). However, for characters with low-frequency semantic radicals (LH and LL), there was no significant difference between the characters with high-frequency phonetic radicals (LH) and those with low-frequency phonetic radicals (LL). Characters with high-frequency phonetic radicals (HH and LH) elicited a larger N400 component than those with low-frequency phonetic radicals (HL and LL), and the N400 differences induced by the neighborhood size of phonetic radicals with high-frequency semantic radicals (HH and HL) were larger than those induced by characters with low-frequency semantic radicals (LH and LL). These results indicate that in the early stage of phonogram recognition, the neighborhood effect of phonetic radicals is regulated by the neighborhood size of semantic radicals. In the late stage of phonogram recognition, the higher the frequency of phonetic radicals, the stronger the semantic activation degree of the character. In general, the neighborhood size of phonetic radicals was found to affect vocabulary accessibility. However, the effect of the neighborhood size of phonetic radicals is regulated by the neighborhood size of semantic radicals. "
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2019-01-03 Cooperative journals: 《计算机应用研究》
Abstract： Degraded document images have various degradation factors, such as page stains, ink bleed-through, and background texture. We propose a novel document image binarization algorithm based on background estimation and U-Net. The algorithm first performs image contrast enhancement, and estimates the document background via morphological closing operations. We then adopt a fully convolutional network, namely the U-Net, to extract the foreground text from the document background. Finally, the global optimal thresholding method is used to obtain the resulting binary image. The proposed technique has been extensively evaluated over the recent DIBCO benchmark datasets. Experimental results show that our proposed method outperforms other state-of-the-art document image binarization algorithms in terms of F-measure, pseudo F-measure, PSNR and DRD, with 5.58%、2.47%、0.86dB and 1.19%.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To explore the risk factors of ventilator-associated pneumonia (VAP) in patients admitted in an intensive care unit (ICU) for pulmonary tuberculosis (TB). Methods The clinical data of 143 patients admitted in the ICU at our center between January, 2014 and June, 2015 were reviewed. The patients with VAP and those without VAP were analyzed for risk factors of VAP in the setting of an ICU for pulmonary TB and compared for the duration of ventilation and hospital stay. Results The patients with pulmonary TB showed a significantly higher incidence of VAP in the ICU than those without TB. Univariate analysis suggested that the occurrence of VAP was significantly correlated with the duration of mechanical ventilation, invasive examination, pulmonary tuberculosis, lung structure changes, use of multiple antibiotics, diabetes, tracheal incision, indwelling gastric tube, APACHE II score, and coma (P<0.05). Multivariate logistic regression analysis showed that pulmonary TB, duration of mechanical ventilation, APACHE II score, invasive operation, and use of multiple antibiotics were independent risk factors for VAP (P<0.05). The patients who developed VAP had a prolonged duration of mechanical ventilation and ICU stay (P<0.05). Conclusion Patients admitted in tuberculosis ICU are exposed to a high risk of VAP with a high mortality rate as the result of multiple interacting risk factors. Pulmonary TB, prolonged mechanical ventilation, an APACHE II score >15, invasive operation, and use of multiple antibiotics are all independent risk factors for VAP in tuberculosis ICU.
Subjects: Biology >> Bioengineering submitted time 2017-07-24 Cooperative journals: 《中国生物工程杂志》
Abstract： Objective: This study focuses on the influence of overexpression of β-glucosidase regulator BglR on beta-glucosidase activities in Myceliophthora thermophila ATCC42464 by cloning bglr gene and constructing Mtbglr overexpression vector. Methods: The SLIC was adopted to construct Mtbglr overexpression vector and the promoter of MtPpdc and terminator of MtTpdc was used for overexpress bglr gene. The gene expression and β-glucosidase activities were observed by protoplast transformation, real-time quantitative PCR and enzymatic determination. Results: The bglr gene was overexpressed in M. thermophila successfully. The result showed that the β-glucosidase activity and secreted protein concentration of transformant strain Mt8 were 1.7 and 1.9 fold higher, respectively, than that of wild type WT. Conclusion: The expression of bglr increased the β-glucosidase activity in Myceliophthora thermophila under the inducing condition, which laid the theoretical foundation for the regulation of β-glucosidase gene of thermophilic fungi.
Subjects: Biology >> Bioengineering submitted time 2017-07-24 Cooperative journals: 《中国生物工程杂志》
Abstract：古紫质4(Archaerhodopsin 4, aR4)是新近发现的古生菌Halobacterium species xz515红膜上唯一的光敏视黄醛蛋白，具有和细菌视紫红质(Bacteriorhodopsin, bR)相似的质子泵功能，但在中性pH条件下，其质子释放和摄取顺序与bR相反。针对质子供体天冬氨酸97(Aspartic acid 97, D97)对aR4光循环、特别是对质子释放摄取顺序和菌株ATP生成率的影响，采用基因定点突变技术，构建了aR4的单突变体D97N，以及相对应的bR单突变体D96N。采用紫外-可见吸收光谱和闪光动力学光谱技术初步研究突变对视黄醛键合区、光反应中间态M态和O态、质子泵功能以及菌株ATP生成率的影响。结果表明，D97N突变对视黄醛紫外-可见光吸收波长没有太大影响，但造成M态衰减时间的显著延长、质子泵功能的消失以及菌株ATP的生成率大幅降低。与bR中的D96作用相比，D97对aR4质子功能的影响有所不同，这可能与D97所处的一个更为疏水性的胞外侧环境有关。
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