Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：媒体融合发展是传媒领域一场重大而深刻的变革。传统媒体和新兴媒体融合发展,离不开先进技术和先进技术平台的引领和驱动,笔者单位在媒体融合发展思想的指导下,建设了适合通讯社业务的全媒体采编发平台,该平台提供了图片处理、音视频快编等在线工具,能够满足大部分采编人员的需要,但针对专业的图片、音视频采编人员,就需要与第三方专业化生产工具进行融合,进一步借力提升自身平台的融媒体加工能力。
Subjects: Library Science，Information Science >> Library Science submitted time 2023-10-08 Cooperative journals: 《知识管理论坛》
Abstract： [Purpose/significance] Based on the feedforward back-propagation artificial neural network, the paper puts forward the evaluation method of WeChat Official Account information dissemination in finance and economics university library, it aims to provide reference for the operation and popularization of the WeChat Official Account of financial university library. [Method/process] According to the characteristics of the information dissemination of the WeChat Official Account in financial university library, starting from the elements and links in the process of information dissemination, this paper constructs an evaluation index system of information dissemination effect from five dimensions: dissemination subject, dissemination content, information carrier, dissemination skill and dissemination object. By collecting the relevant data of Wechat public number of 30 financial and Economic University libraries, the evaluation index system is based on the feedforward BP neural network model. [Result/conclusion] Based on the feedforward BP Neural network, the paper put forward the evaluation method of WeChat Official Account information dissemination effect in financial university library. Then, through empirical research, it was proved that the evaluation method has a good effect on the evaluation of the propagation effect of WeChat, and according to the evaluation results, the countermeasures and suggestions were put forward to promote the communication effect of the WeChat Official Account in finance and economics University library.
Subjects: Library Science，Information Science >> Library Science submitted time 2023-08-27 Cooperative journals: 《图书情报工作》
Abstract： [Purpose/significance] This study aims to explore the differences between collaborative mode and individual mode of information search on search experience and search interaction, trying to understand the characteristics of collaborative information search from various angles.[Method/process] The experiment is designed based on books interactive retrieval platform (CLEF-Social Book Search). Sixteen independent and eighteen collaborative participants are recruited to the laboratory to complete different types of book search tasks. Users' interactions with the system during search are recorded through the backend server; while their search experience is recorded by questionnaires completed before and after the search. In data analysis, users' interactions and search experience are compared between two search modes.[Result/conclusion] (1) Search experience:Compared with individual searchers, collaborative searchers have better evaluation on experiment system function and higher evaluation on aesthetics, durability, novelty of the system, and participate in the search more intently. However, collaborative searcher felt a bit more frustrated and mentally taxing than individual searchers. (2) Search strategies:Compared with individual searchers, collaborative searchers make more decisions in the goal-oriented task, especially the decision of removing books from bookbag, which indicates collaborative searchers need to sort the books in the later stage. In the open-ended task, collaborative searchers spend more time before each decision than individual searchers, which is probably because of collaborative searcher's higher level of focus and participatory. This study helps understand about collaborative search through comparison with individual search, which may provide inspiration for collaborative search system design.
Subjects: Library Science，Information Science >> Library Science submitted time 2023-08-26 Cooperative journals: 《图书情报工作》
Abstract： [Purpose/significance] It is of great importance to grasp the current status, hotspots, and frontiers of research on knowledge service mode for understanding knowledge service activities and effectively guiding knowledge service practices.[Method/process] Based on defining knowledge service and knowledge service mode, this paper systematically reviews the research status of knowledge service mode through keyword frequency statistics and co-appearance network analysis. Then, through content analysis, this paper explores and discusses the research hotspots and frontiers of knowledge service mode from four elements of knowledge service.[Result/conclusion] The present research shows an increasing trend at home and abroad, and has several differences between them. Current research hotspots are discussions on innovation-oriented, user-oriented, technology-oriented and domain-oriented knowledge service modes. Future research frontiers will be knowledge service mode in open innovation,knowledge service innovation mode with design thinking, knowledge management mode under big data environment and the application of knowledge service mode in the field of healthcare.
Subjects: Library Science，Information Science >> Library Science submitted time 2023-08-26 Cooperative journals: 《图书情报工作》
Abstract： [Purpose/significance] In view of the realistic problems of cultural heritage institutions' user service channel blocking,insufficient contact with target users,low utilization rate of collection resources existing in libraries, museums and archives, based on "Internet + traditional collection information service", this paper explores the feasibility of online to offline service mode.[Method/process]The paper uses literature review to analyze the drawback of traditional mode,and O2O mode's application in the field of LAM theoretically, illustrates the present situation of internal cultural heritage institutions' application of O2O service method, puts forward traditional collection O2O information service mode, explains its connotation, elements and forms, and discusses the practical operation and service process.[Result/conclusion]Cultural heritage institutions are adapting to the changes in digital age. The traditional collection O2O information service mode accords with this tendency,and is helpful to user service development and transformation of LAM.
Subjects: Library Science，Information Science >> Information Science submitted time 2023-04-01 Cooperative journals: 《图书情报工作》
Abstract： [Purpose/significance] Requirement has always been the key to improve service quality and level. Exploring effective knowledge service mode from the perspective of client requirement is of great significance to guarantee the knowledge service quality and improve the service level and influence of think tanks. [Method/process] Through literature review, this paper summarized the types of client requirements for think-tank knowledge service and the knowledge service modes of think tanks. Then a questionnaire survey was used to collect data from two client groups, including government employees and the public. This paper analyzed the clients’ cognition degree, intensity of requirements and service mode selection intention for think tank knowledge services, and analyzed the relationships between client requirements and knowledge service modes of think tanks through partial least squares regression model. [Result/conclusion] The cognition degree of government employees to think tank knowledge service is significantly higher than that of the public. And government employees have a better understanding of party and government think tanks, while the public has a better understanding of university think tanks. The intensity of clients’ requirements for the knowledge services of think tanks from high to low are talent support, policy research, decision-making consultation and public opinion propaganda. Clients’ willingness to choose different knowledge service modes of think tanks is, from high to low, open media, open publication, offline communication and internal cooperation. Moreover, clients’ requirements for various knowledge service modes have a significant positive impact on the different knowledge service modes of think tanks.
Subjects: Library Science，Information Science >> Information Science submitted time 2023-04-01 Cooperative journals: 《图书情报工作》
Abstract： [Purpose/significance] To further improve the theory of information needs, and optimize network health information service, this paper analyzed the motivation and topic of college students' health information needs in public health emergencies. [Method/process] In this paper, public health emergencies within the scope of China in early 2020 were taken as the context and self-reported information needs of search users were taken as the analysis object. This paper adopted the method of content analysis, open coding and association rules to analyze distribution, evolution and correlation. [Result/conclusion] The study found that college students' health information needs in public health emergencies are balanced by individual and social motivation; the study found that the topic of health information needs in public health emergencies focused on epidemic situation and trend, disease prevention, etiology pathology and diagnosis, government behavior and social phenomena; with the evolution of public health emergencies, the focus topics of health information needs changes steadily; the motivation and topics are significantly correlated; epidemic situation and trend, social phenomena and government behavior are driven by social motivation, while individual motivation mainly drives disease prevention, etiology, pathology and diagnosis.
Subjects: Psychology >> Social Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： I3 model, which is also known as “I-cubed model”, has shaped a theoretical framework for explaining individual behavior, which argues that all behaviors emerge from a combination of instigation, impellance and inhibition. Each factor can change independently of the other two. The structure of I3 model is a comprehensive model of 12 paths consisting of three factors (instigation, impellance, and inhibition), a mediator (behavioral proclivity), and an outcome (behavior). The 12 paths predict the individual behavior mechanism in specific contexts by describing 18 problems, such as aggressive behaviors, eating behaviors, etc. As a theoretical framework for behavior research, Finkel and other researchers verified and supported the theory with empirical studies on a large number of studies over the past 10 years, which suggests that the theory is consistent with the data. In addition, in terms of the self-consistent nature of the model system, the I3 model has certain rationality, compatibility, and unique value compared with other classical theories and behavior models. First, the I3 model is compatible with the Planned Behavior Theory and Dual-Process Theory. In this sense, Finkel demonstrates the rationality of constructing I3 model by referring to the behavioral tendency of the Planned Behavior Theory and the behavior reaction of the Dual-Process Theory. Second, the I3 model has its own peculiarities as well as its superficial similarities with general behavioral models such as the "S-O-R'' model. Overall, Finkel tries to combine the research results and theoretical viewpoints under various mediating and regulating research paradigms to establish a grand theoretical system of human behavior. Third, in the same way, Finkel specifically analyzes the similarities and differences of I3 model with General Aggression Model and Goal Conflict Model in explaining the attack behavior and feeding behavior, thus revealing the uniqueness of I3 model. However, this model has the following problems: (1) From the perspective of the entire research system, this model is only a scientific theory and has not yet reached the level of a metatheory. (2) From the perspective of theoretical guidance, the model does not clearly explain the boundary conditions and scope of the theory, and does not consider the sources of other research questions. Although various main effects and interaction tests have been examined, it is still a data-driven test, and it does not reveal the actual interaction mechanism of these three forces; (3) From the practical application, the I3 model only focuses the individual behaviors, such as eating behaviors and aggressive behaviors, few researchers explore other individual behaviors and social behaviors, such as prosocial behaviors, learning behaviors, etc. There are also certain flaws in the interpretation of some specific behaviors and the explanation of some specific behaviors also has certain defects. Consequently, it is necessary to broaden the field of behavioral research on the I3 model in the future, not only to analyze the subtypes of the behavior and the types of behavior in different scenarios but also to explore the tendency and intention of the individual behavior; Secondly, we should apply the I3 model according to local condition, which needs to determine the type and quantity of factors combined with specific research problems, so as to achieve the results we want; Last but not least, we should integrate I3 model with other theories, and further explore the boundary conditions of I3 model. In summary, I3 model improves explanatory power of behavior theory to various behavior types and meets the current concern regarding behavioral research, such as behavior nudge and network behavior, and enriches theoretical support and theoretical framework for behavioral analysis.
Subjects: Psychology >> Social Psychology submitted time 2023-03-27 Cooperative journals: 《心理学报》
Abstract： With the development of science, the internet has become an indispensable tool in college students' study and daily life. However, online aggressive behavior has become a much more serious problem for college students in recent few years. It is necessary to find out which factors have significant effects on online aggressive behavior of college students. According to the previous researches, the violent exposure was found to be able to predict aggressive behavior significantly. In addition, some theorists also have confirmed that ruminative responses and aggressive behavior are strongly related. However, as a special form of aggressive behavior, there was little research focused on online aggressive behavior and violent exposure. So the purposes of the present study is to explore the relationship between violent exposure, ruminative responses, internet moral and online aggressive behavior as well as the mechanism the effect of violent exposure on online aggressive behavior of college students.A total sample of 1000 college students from some universities was selected, with 326 males and 508 females, the average age was 20.74-year-old. All subjects were gathered in the class and finished the questionnaires within about 30 minutes. The questionnaires included the Violent Exposure Questionnaire (VEQ), Online Aggressive Behavior Scale (OABS), Ruminative Responses Scale (RSS), and the Internet Moral Questionnaire (IMQ). Data was collected and analyzed with SPSS 24.0, Amos 21.0 and Mplus 7.4, and the bias-corrected percentile Bootstrap method was used to analyze the role of ruminative responses and internet moral between violent exposure and college students' online aggressive behavior. A single factor analysis was calculated to test the common method variance. Results showed that the study was in-existent common method variance.The results show that: (1)The relationships between each pair of violent exposure, ruminative responses, internet moral and online aggressive behavior are correlated significantly and positively, the correlation coefficient ranges 0.07 from 0.96 (p < 0.01); (2)The structural equation model (SEM) reveals that the data fits the theoretical model well (c 2/df = 2.45, CFI = 0.99, TLI = 0.98, SRMR = 0.03, RMSEA = 0.04). (3) Violent exposure has a significant direct effect on online aggressive behavior (β = 0.29, p < 0.01); Violent exposure has a significant direct effect on ruminative responses (β = 0.23, p < 0.01); Ruminative responses has a significant direct effect on online aggressive behavior (β = 0.17, p < 0.01); Internet moral has a significant direct effect on online aggressive behavior (β = -0.17, p < 0.01); Interaction has a significant direct effect on online aggressive behavior (β = -0.17, p < 0.01). (4)Violent exposure has a significant indirect effect on online aggressive behavior through ruminative responses, and the confidence interval of 95% is [0.025, 0.061]; (5) Internet moral moderates the relation between violent exposure and online aggressive behavior of college students, that is, there is a significant positive relation between violent exposure and online aggressive behavior under the low internet moral level, however, there is a non-significant relation between violent exposure and online aggressive behavior under the high internet moral level. It is concluded that in the structural equation model of violent exposure on online aggressive behavior of college students, ruminative responses plays a partial mediating role and internet moral moderates the direct effect. These findings suggest some measures of prevention and treatment for college students’ online aggressive behavior should be taken. Schools and families should set up a good core self-evaluation system in order to help them improve their moral level and eradicate online aggressive behavior.
Subjects: Psychology >> Social Psychology submitted time 2023-03-27 Cooperative journals: 《心理学报》
Abstract： Upward social comparison is common in workplaces, and many studies have identified its downsides, such as negative emotions and dysfunctional behaviors. However, a few studies have revealed positive effects, such as learning from comparison targets. These conflicting results suggest that the mechanism underlying the effect of upward social comparison in workplaces remains unclear. Furthermore, most research is based on social comparison theory, whereas few studies have explored upward social comparison through a cognitive lens. To fill these research gaps, we drew on the cognitive appraisal theory of stress to investigate upward social comparison in the workplace and determine how and when it yields (mal) adaptive behavioral outcomes. We used a multi-wave, round-robin design to collect data. 270 employees from 65 teams agreed to participate. At Time 1, 270 employees were invited to assess their workplace upward social comparison, performance-prove goal orientation, social comparison orientation, learning goal orientation, and demographics. 251 employees provided valid responses (response rate = 93%). Two weeks after Time 1, 251 employees were invited to evaluate their challenge and threat appraisals, and 240 employees provided valid responses (response rate = 95.6%). Two weeks after Time 2, 240 employees were invited to report their learning behaviors towards their coworkers, and meanwhile, employees were invited their received social undermining from coworkers. 240 valid responses were received (response rate = 100%). Finally, 720 dyads from 240 employees from 60 teams were used to test our proposed model. Given that the dyads nested in employees and then employees nested within teams, we tested our hypothesis by multilevel social relations model. To test the conditional indirect effects, a Monte Carlo simulation with 20, 000 replications was used to generate the 95% Monte Carlo confidence intervals in R 3.5. The results showed that employees with low levels of performance-prove goal orientation tended to appraise upward social comparison as a challenge, which prompts learning from the comparison targets. However, employees with high levels of performance-prove goal orientation tended to appraise upward social comparison as a threat, motivating them to socially undermine the comparison targets. Our study provides theoretical and practical implications. We reveal the double-edged effects of workplace upward social comparison on subsequent learning behaviors and social undermining through a cognitive rather than emotional lens. Our findings demonstrate how and why workplace upward social comparison drives employees to develop two distinct behavioral responses, from a novel theoretical perspective—the cognitive appraisal theory of stress. Finally, the performance-prove goal orientation determines the effects of workplace upward social comparison. Furthermore, our findings offer important practical implications to managers and policymakers.
Subjects: Mathematics >> Control and Optimization. submitted time 2023-01-27
Abstract： This paper deals with the uniform exponential stabilities (UESs) of two hybrid control systems consisting of wave equation and a second-order ordinary differential equation. Linear feedback law and local viscosity, and nonlinear feedback law and interior anti-damping are considered, respectively. Firstly, the hybrid system is reduced to a first order port-Hamiltonian system with dynamical boundary conditions and the resulting systems are then discretized by average central-difference scheme. Secondly, the UES of the discrete system is obtained without prior knowledge on the exponential stability of continuous system. The frequency domain characterization of UES for a family of contractive semigroups and discrete multiplier method are utilized to verify main results, respectively. Finally, the convergence analysis of the numerical approximation scheme is performed by the Trotter-Kato Theorem. Most interestingly, the exponential stability of the continuous system is derived by the convergence of energy and UES and this is a new idea to investigate the exponential stability of some complicate systems. The effectiveness of the numerical approximating scheme is verified by numerical simulation.
Peer Review Status:
Awaiting Review
Subjects: Psychology >> Management Psychology submitted time 2022-10-25
Abstract： Upward social comparison is common in workplaces, and many studies have identified its downsides, such as negative emotions and dysfunctional behaviors. However, a few studies have revealed positive effects, such as learning from comparison targets. These conflicting results suggest that the mechanism underlying the effect of upward social comparison in workplaces remains unclear. Furthermore, most research is based on social comparison theory, whereas few studies have explored upward social comparison through a cognitive lens. To fill these research gaps, we drew on the cognitive appraisal theory of stress to investigate upward social comparison in the workplace and determine how and when it yields (mal)adaptive behavioral outcomes. We used a multi-wave, round-robin design to collect data. 270 employees from 65 teams agreed to participate. At Time 1, 270 employees were invited to assess their workplace upward social comparison, performance-prove goal orientation, social comparison orientation, learning goal orientation, and demographics. 251 employees provided valid responses (response rate = 93%). Two weeks after Time 1, 251 employees were invited to evaluate their challenge and threat appraisals, and 240 employees provided valid responses (response rate = 95.6%). Two weeks after Time 2, 240 employees were invited to report their learning behaviors towards their coworkers, and meanwhile, employees were invited their received social undermining from coworkers. 240 valid responses were received (response rate = 100%). Finally, 720 dyads from 240 employees from 60 teams were used to test our proposed model. Given that the dyads nested in employees and then employees nested within teams, we tested our hypothesis by multilevel social relations model. To test the conditional indirect effects, a Monte Carlo simulation with 20,000 replications was used to generate the 95% Monte Carlo confidence intervals in R 3.5. The results showed that employees with low levels of performance-proving goal orientation tended to appraise upward social comparison as a challenge, which prompts learning from the comparison targets. However, employees with high levels of performance-proving goal orientation tended to appraise upward social comparison as a threat, motivating them to socially undermine the comparison targets. Our study provides theoretical and practical implications. We reveal the double-edged effects of workplace upward social comparison on subsequent learning behaviors and social undermining through a cognitive rather than emotional lens. Our findings demonstrate how and why workplace upward social comparison drives employees to develop two distinct behavioral responses, from a novel theoretical perspective—the cognitive appraisal theory of stress. Finally, the performance-proving goal orientation determines the effects of workplace upward social comparison. Furthermore, our findings offer important practical implications to managers and policymakers.
Subjects: Biology >> Botany >> Applied botany submitted time 2021-04-29 Cooperative journals: 《广西植物》
Abstract： Solanum diphyllum is a kind of small shrub from Solanaceae, little is known about its Cd tolerance ability in the existed researches so far. In order to investigate the physiological responses, growth responses and Cd tolerance characteristics of S. diphyllum seedlings, we conducted a hydroponic experiment with 160 μM Cd stress to determine the indexes of growth (taproot, height, stem diameter, leaf number, biomass, and root to shoot ratio), tolerance ability, Cd content, Cd accumulation characteristics, SOD activity, osmotic adjustment substances (MDA, free proline and soluble sugar), and photosynthetic pigment (Chlorophyll a, Chlorophyll b and carotenoid) in different stress time (0, 0.5, 1, 3, 7, 19 d). The results showed that: compared with controls, Cd had no significant effect on the growth of S. diphyllum seedlings when stress time is 0-3 d, but obvious Cd toxicity was aggravated with the prolonging of Cd stress time (3-19 d). During the period of experiment, Cd stress reduced the total biomass of S. diphyllum seedlings by 13.28%-62.40%, root suffered the most serious biomass damage among different plant tissues. The maximum Cd accumulation of the whole plant was 60.14 μg·plant-1, for root and shoot the maximum Cd accumulation were 43.49 μg·plant-1 and 16.65 μg·plant-1 respectively, Cd accumulation of shoots accounted for 15.46%-35.24% of the whole plant. MDA content of S. diphyllum seedlings increased with increasing stress time, the maximum increase of MDA content in roots was 5.25 times than that of control. SOD activity, the content of free proline and soluble sugars, as well as photosynthetic pigments content showed a trend of increased in the beginning and then decreased. Tolerance index (TI) showed a different tendency, it decreased with increasing time, the minimum value of S. diphyllum seedlings during the whole period of experiment was 0.64. The above results showed that S. diphyllum seedlings have a certain degree of tolerance to high concentration of Cd stress (160 μM), which suggests it is a potential Cd tolerance plant. The osmotic adjustment and root retention might be the main methods of S. diphyllum seedlings to alleviated toxicity to plant growth caused by Cd. This research provides a theoretical basis for finding suitable phytoremediation materials.
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-11-20 Cooperative journals: 《干旱区地理》
Abstract：利用1960—2018年锡林河流域周边13个气象站的逐日气象资料，采用世界粮农组织（Food and Agriculture Organization of the United Nations，FAO）推荐的Penman-Monteith公式计算各气象站多年潜在蒸散发量及相对湿润度指数。通过利用主成分分析、相关分析和偏相关分析，探讨了锡林河流域潜在蒸散发、地表干湿状况多年变化规律；分析了影响潜在蒸散发的主要气象因子及各气象要素间的相互作用；着重讨论了锡林河流域潜在蒸散发的周期变化及其与相对湿润度指数、各气象要素的相互作用。结果表明：流域近59 a潜在蒸散发整体呈现增长趋势，且上升趋势显著，存在显著增加—减小交替的多尺度时频变化特征和多主周期变化规律；各气象要素中潜在蒸散发对温度的响应较大，平均风速次之；平均相对湿度受到潜在蒸散发的影响较大，降水次之。整个流域环境有不显著的变湿润趋势。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-07-20 Cooperative journals: 《干旱区研究》
Abstract：以锡林河流域内及周边13个国家气象站逐日气象观测数据为基础，采用标准化降水蒸散指数（SPEI），借助Mann-Kendall与Mann Whitney Pettitt突变检验、非参数统计检验以及重标极差R/S分析法，深入剖析锡林河地区多年干旱演变趋势及未来干旱预测。结果表明；锡林河地区干旱突变开始于20世纪90年代；近60 a来，SPEI表现出显著减小趋势，上游减小趋势较中下游段小，中下游段为旱情多发带，下游西北端是干旱存在的危险区域。在未来，流域旱情将有所缓解，但冬季旱情有持续加重的可能，应加强干旱监测。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-11 Cooperative journals: 《干旱区研究》
Abstract：为了验证SRM（snowmelt-runoff model）融雪径流模型在寒旱区草原流域的适用性，在阐述模型结构、参数意义的基础上，结合锡林河流域上游2014—2016年融雪期（3—5月）的MODIS积雪覆盖数据及实测气象、水文资料，采用WinSRM 1.10版本对2014—2016年锡林河上游年融雪期的径流进行模拟，结果发现：SRM模型可以较好地反映锡林河融雪期径流变化趋势，有效捕捉融雪径流洪峰到达日期及洪峰流量。对模型进行精度评价，得出3 a模拟值的拟合优度确定系数（R2）与体积差（DV）均优于世界气象组织公布的模型模拟精度均值。所以，SRM融雪径流模型在锡林河流域上游具有较好的适用性，这对合理利用草原冰雪水资源具有重要意义。
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-06-19 Cooperative journals: 《计算机应用研究》
Abstract： Text similarity calculation is a significant part with great research value in the field of NLP (Natural Language Processing) . The calculation of text similarity with LDA (Latent Dirichlet Allocation) model takes into account the semantic features, but it has the disadvantages of a large number of words, unconformity of the semantics of words, and the inability to dig and exploit the inter-domain differences inherent in texts of different categories. This paper proposes WMF_LDA topic model (Word Merging and Filtering_LDA) . This model maps domain words and synonyms, and filters the words based on POS. Finally, LDA theme is used on the processed result. Experiments show that this method greatly reduces the amount of words during modeling, reduces the time consumption of the modeling process, and improves the speed of the final text clustering. And compared with other text similarity methods, the method proposed in this paper also has a certain degree of improvement in accuracy.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the effects of treadmill exercise on central hemodynamics in patients with coronary artery disease. Methods Sixty-eight consecutive patients below 60 years of age with the diagnosis of coronary artery disease (CAD) between July, 2013 and April, 2014 underwent treadmill exercise test following the standard Bruce protocol. Ninety-seven individuals without CAD served as the control group. Central hemodynamics of the subjects, including the central aortic blood pressure (cSBP), augmentation index (AI) and augmentation pressure (AP), were examined before and after the exercise. Results cSBP increased significantly after acute exercise in both groups (P<0.001). Immediately after treadmill exercise, AI showed no significant changes in CAD patients (P=0.561) but decreased significantly in the control subjects (P<0.001). AI before exercise and cSBP after exercise were significantly higher in CAD group than in the control group (P=0.009 and 0.009, respectively). Stepwise regression analysis showed that the maximal heart rate after exercise was the main factor that affected cSBP increment in CAD group (P=0.012), and the occurrence of ischemia after exercise was associated with a lower cSBP increment (P=0.048). Conclusion AI does not decrease significantly after acute exercise in patients with CAD, suggesting that AI is closely associated with coronary artery blood perfusion after exercise and may serve as a potential target for improving ischemic threshold during rehabilitation of the patients.
Subjects: Biology >> Zoology submitted time 2017-10-10 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究棕榈油替代大豆油对吉富罗非鱼幼鱼生长性能、肌肉组成和血清生化指标的影响。选用初始体重为8.80 g的吉富罗非鱼幼鱼600尾，随机分为5组，每组3个重复，每重复40尾。5组试验鱼分别投喂以棕榈油替代基础饲料中0（对照）、25%、50%、75%、100%大豆油的5种等氮（31.60%）等脂（9.30%）饲料，分别记为G0、G25、G50、G75、G100。试验期为56 d。结果表明：1）棕榈油替代不同比例的大豆油对罗非鱼幼鱼的终末体重、增重率、特定生长率、饲料系数和存活率均无显著影响（P＞0.05）。2）与G0组相比，各棕榈油组（G25、G50、G75、G100组）罗非鱼幼鱼的肥满度、脏体比、肝体比以及肌肉水分、粗蛋白质、粗脂肪、粗灰分含量无显著变化（P＞0.05）；G50组肌肉粗脂肪含量显著高于G100组（P＜0.05）。3）棕榈油替代不同比例的大豆油对罗非鱼幼鱼血清胆固醇、甘油三酯、低密度脂蛋白胆固醇和总蛋白含量的影响不显著（P＞0.05）。与G0组相比，G50、G100组血清高密度脂蛋白胆固醇含量，G25、G50组血清谷丙转氨酶活性及G50、G75组血清谷草转氨酶活性显著降低（P＜0.05）。由此得出，以生长性能为评价指标，吉富罗非鱼幼鱼饲料中的大豆油可全部被棕榈油替代；棕榈油替代大豆油比例超过50%时，显著影响吉富罗非鱼幼鱼肌肉粗脂肪含量、部分血清生化指标。
Subjects: Biology >> Zoology submitted time 2017-10-10 Cooperative journals: 《动物营养学报》
Abstract：本研究旨在探讨饲料中不同维生素D含量对鲈鱼幼鱼生长性能和钙磷代谢的影响。以初始体重为（2.26±0.03） g的鲈鱼幼鱼为试验对象，随机分为6组（每组3个重复，每个重复15尾鱼），饲喂维生素D含量实测值分别为34.2、219.4、393.8、775.9、1 534.1和3 091.2 IU/kg的等氮等能饲料，进行9周的养殖试验。结果表明：1）当饲料中维生素D含量在34.2~393.8 IU/kg时，鲈鱼的增重率随着饲料中维生素D含量的升高显著上升（P0.05）。同样，鲈鱼的特定生长率、饲料效率和蛋白质效率均表现出与增重率相似的变化趋势。2）饲料中维生素D含量显著影响了鱼体粗灰分、钙和磷含量，脊椎骨、鳃盖骨和鳞片粗灰分含量以及脊椎骨钙和磷含量（P0.05）。3）饲料中维生素D含量对鲈鱼血清碱性磷酸酶活性及羟脯氨酸、钙离子和无机磷含量均有显著影响（P<0.05）。4）饲料中维生素D含量显著影响了鲈鱼肝体指数及肝脏脂肪和维生素D含量（P<0.05）。随着饲料中维生素D含量的升高，肝脏维生素D含量呈现升高的趋势，并在饲料中维生素D含量达到1 534.1 IU/kg时变化趋于平稳。以增重率为评价指标，采用折线模型分析得出鲈鱼幼鱼获得最大生长时对饲料中维生素D的需求量为431.0 IU/kg。以肝脏维生素D含量为评价指标，采用二次曲线模型分析得出鲈鱼幼鱼获得最大肝脏维生素D沉积量时对饲料中维生素D的需求量为2 444.4 IU/kg。
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