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Improving the nutritional values of yellow mealworm Tenebrio molitor(Coleoptera: Tenebrionidae) larvae as an animal feed ingredient: a review 被引量:1
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作者 Linggawastu Syahrulawal Magnhild Oust Torske +2 位作者 Rumakanta Sapkota Geir Næss Prabhat Khanal 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期35-52,共18页
Yellow mealworm larvae(YML;Tenebrio molitor) are considered as a valuable insect species for animal feed due to their high nutritional values and ability to grow under different substrates and rearing conditions. Adva... Yellow mealworm larvae(YML;Tenebrio molitor) are considered as a valuable insect species for animal feed due to their high nutritional values and ability to grow under different substrates and rearing conditions. Advances in the understanding of entomophagy and animal nutrition over the past decades have propelled research areas toward testing multiple aspects of YML to exploit them better as animal feed sources. This review aims to summarize various approaches that could be exploited to maximize the nutritional values of YML as an animal feed ingredient. In addition, YML has the potential to be used as an antimicrobial or bioactive agent to improve animal health and immune function in production animals. The dynamics of the nutritional profile of YML can be influenced by multiple factors and should be taken into account when attempting to optimize the nutrient contents of YML as an animal feed ingredient. Specifically, the use of novel land-based and aquatic feeding resources, probiotics, and the exploitation of larval gut microbiomes as novel strategies can assist to maximize the nutritional potential of YML. Selection of relevant feed supplies, optimization of ambient conditions, the introduction of novel genetic selection procedures, and implementation of effective post-harvest processing may be required in the future to commercialize mealworm production. Furthermore, the use of appropriate agricultural practices and technological improvements within the mealworm production sector should be aimed at achieving both economic and environmental sustainability. The issues highlighted in this review could pave the way for future approaches to improve the nutritional value of YML. 展开更多
关键词 Alternative protein source Feed application Nutritional value Yellow mealworm
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On the Role of Security in the System of Personal Values:Are Conservatives Prioritizing Security?
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作者 Ingwer Borg 《Macro Management & Public Policies》 2023年第2期1-13,共13页
Security is a value contained in most theories of personal values.Yet,while the relations among the most basic values are clear and reliable,the role of security in the system of values remains ambiguous.People strivi... Security is a value contained in most theories of personal values.Yet,while the relations among the most basic values are clear and reliable,the role of security in the system of values remains ambiguous.People striving for security are often also striving for tradition and conformity but sometimes they are focusing more on other values(such as health values,for example).Based on eight representative surveys(N=24,000)in several German cities between 1998 and 2022,the author shows that when measuring security without suggesting a particular meaning of this notion,security takes a relatively central position within the system of values and their components(shown by multidimensional scaling,MDS).People striving for security also emphasize the importance of law and order,working hard,and having a good family life as guiding principles in their lives.Conformity is not that important for them,and having an exciting life is even negatively correlated.Age has little impact on the MDS structure of values and their components,even though people exhibit substantial changes in the relative weights they assign to many values as they get older. 展开更多
关键词 Personal values SECURITY Value circle Age GENDER Multidimensional scaling
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A Study on the Explainability of Thyroid Cancer Prediction:SHAP Values and Association-Rule Based Feature Integration Framework
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作者 Sujithra Sankar S.Sathyalakshmi 《Computers, Materials & Continua》 SCIE EI 2024年第5期3111-3138,共28页
In the era of advanced machine learning techniques,the development of accurate predictive models for complex medical conditions,such as thyroid cancer,has shown remarkable progress.Accurate predictivemodels for thyroi... In the era of advanced machine learning techniques,the development of accurate predictive models for complex medical conditions,such as thyroid cancer,has shown remarkable progress.Accurate predictivemodels for thyroid cancer enhance early detection,improve resource allocation,and reduce overtreatment.However,the widespread adoption of these models in clinical practice demands predictive performance along with interpretability and transparency.This paper proposes a novel association-rule based feature-integratedmachine learning model which shows better classification and prediction accuracy than present state-of-the-artmodels.Our study also focuses on the application of SHapley Additive exPlanations(SHAP)values as a powerful tool for explaining thyroid cancer prediction models.In the proposed method,the association-rule based feature integration framework identifies frequently occurring attribute combinations in the dataset.The original dataset is used in trainingmachine learning models,and further used in generating SHAP values fromthesemodels.In the next phase,the dataset is integrated with the dominant feature sets identified through association-rule based analysis.This new integrated dataset is used in re-training the machine learning models.The new SHAP values generated from these models help in validating the contributions of feature sets in predicting malignancy.The conventional machine learning models lack interpretability,which can hinder their integration into clinical decision-making systems.In this study,the SHAP values are introduced along with association-rule based feature integration as a comprehensive framework for understanding the contributions of feature sets inmodelling the predictions.The study discusses the importance of reliable predictive models for early diagnosis of thyroid cancer,and a validation framework of explainability.The proposed model shows an accuracy of 93.48%.Performance metrics such as precision,recall,F1-score,and the area under the receiver operating characteristic(AUROC)are also higher than the baseline models.The results of the proposed model help us identify the dominant feature sets that impact thyroid cancer classification and prediction.The features{calcification}and{shape}consistently emerged as the top-ranked features associated with thyroid malignancy,in both association-rule based interestingnessmetric values and SHAPmethods.The paper highlights the potential of the rule-based integrated models with SHAP in bridging the gap between the machine learning predictions and the interpretability of this prediction which is required for real-world medical applications. 展开更多
关键词 Explainable AI machine learning clinical decision support systems thyroid cancer association-rule based framework SHAP values classification and prediction
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Effect of FeSi additive in dual-chamber sample cup on thermal analysis characteristic values and vermiculating rate of compacted graphite iron
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作者 De-quan Shi Ze-yu Liu +1 位作者 Gui-li Gao Yi-cheng Feng 《China Foundry》 SCIE EI CAS CSCD 2024年第1期91-100,共10页
Thermal analysis plays a key role in the online inspection of molten iron quality.Different solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements af... Thermal analysis plays a key role in the online inspection of molten iron quality.Different solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements affecting the solidification of molten iron.In this study,FeSi75 was added in one chamber of the dual-chamber sample cup,and the influences of FeSi75 additive on the characteristic values of thermal analysis curves and vermiculating rate were investigated.The results show that with the increase of FeSi75,the start temperature of austenite formation TALfirstly decreases and then increases,but the start temperature of eutectic growth TSEF,the lowest eutectic temperature TEU,temperature at maximum eutectic reaction rate TEM,and highest eutectic temperature TERkeep always an increase.The temperature at final solidification point TEShas little change.The FeSi75 additive has different influences on the vermiculating rate of molten iron with different vermiculation,and the vermiculating rate increases for lower vermiculation molten iron while decreases for higher one.According to the thermal analysis curves obtained by a dual-chamber sample cup with 0.30wt.%FeSi75 additive in one chamber,the vermiculating rate of molten iron can be evaluated by comparing the characteristic values of these curves.The time differenceΔtERcorresponding to the highest eutectic temperature TERhas a closer relationship with the vermiculating rate,and a parabolic regression curve between the time differenceΔtERand vermiculating rateηhas been obtained within the range of 65%to 95%,which is suitable for the qualified melt. 展开更多
关键词 FeSi75 additive characteristic value vermiculating rate thermal analysis compacted graphite iron
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A New Solution to Intrusion Detection Systems Based on Improved Federated-Learning Chain
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作者 Chunhui Li Hua Jiang 《Computers, Materials & Continua》 SCIE EI 2024年第6期4491-4512,共22页
In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of enterprises.With systems spanning various sectors of enterprises geographically dispersed... In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of enterprises.With systems spanning various sectors of enterprises geographically dispersed,the necessity for seamless information exchange has surged significantly.The existing cross-domain solutions are challenged by such issues as insufficient security,high communication overhead,and a lack of effective update mechanisms,rendering them less feasible for prolonged application on resource-limited devices.This study proposes a new cross-domain collaboration scheme based on federated chains to streamline the server-side workload.Within this framework,individual nodes solely engage in training local data and subsequently amalgamate the final model employing a federated learning algorithm to uphold enterprise systems with efficiency and security.To curtail the resource utilization of blockchains and deter malicious nodes,a node administration module predicated on the workload paradigm is introduced,enabling the release of surplus resources in response to variations in a node’s contribution metric.Upon encountering an intrusion,the system triggers an alert and logs the characteristics of the breach,facilitating a comprehensive global update across all nodes for collective defense.Experimental results across multiple scenarios have verified the security and effectiveness of the proposed solution,with no loss of its recognition accuracy. 展开更多
关键词 Cross-domain collaboration blockchain federated learning contribution value node management release slack resources
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Spatio-temporal evolution and topographic gradient effect of land use and ecosystem service value in the Lhasa River Basin
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作者 ZHOU Jianwei FENG Bin +8 位作者 WU Hua XU Tong CHEN Linna ZHAO Xinyong GUO Qiyun LI Jiatong ZHANG Chenguang ZHU Kangcheng KONG Yuzhong 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2059-2074,共16页
The Lhasa River Basin forms an essential human settlement area in the southern part of the Qinghai-Tibet Plateau.This study employed ecosystem service value(ESV)evaluation model,terrain gradient grading,and Geodetecto... The Lhasa River Basin forms an essential human settlement area in the southern part of the Qinghai-Tibet Plateau.This study employed ecosystem service value(ESV)evaluation model,terrain gradient grading,and Geodetector to analyze land use and ESV in the Lhasa River Basin from 1985 to 2020.The findings reveal that:(1)From 1985 to 2020,grassland was the dominant land use.There was a trend of grassland reduction and the expansion of other land types.(2)ESV has increased over the research period(with a total increase of 0.84%),with higher values in the southeast and lower values in the northwest.Grassland contributed the most to ESV,and climate regulation and hydrological regulation were the ecosystem services that contribute the most to ESV.(3)Natural factors like NDVI and altitude,as well as economic factors like population density and distance from roads,influenced the spatial differentiation of ESV,the explanatory power of NDVI reached up to 0.47.The interaction between factors had a greater impact than individual factors.These research results can provide theoretical support for national spatial planning and ecological environment protection in the Lhasa River Basin and other similar areas. 展开更多
关键词 Ecosystem services value Land use Terrain gradient effect Lhasa River Basin Driving factors
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Spatiotemporal Variability and Environmental Controls of Temperature Sensitivity of Ecosystem Respiration across the Tibetan Plateau
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作者 Danrui SHENG Xianhong MENG +8 位作者 Shaoying WANG Zhaoguo LI Lunyu SHANG Hao CHEN Lin ZHAO Mingshan DENG Hanlin NIU Pengfei XU Xiaohu WEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1821-1842,共22页
Warming-induced carbon loss via ecosystem respiration(R_(e))is probably intensifying in the alpine grassland ecosystem of the Tibetan Plateau owing to more accelerated warming and the higher temperature sensitivity of... Warming-induced carbon loss via ecosystem respiration(R_(e))is probably intensifying in the alpine grassland ecosystem of the Tibetan Plateau owing to more accelerated warming and the higher temperature sensitivity of R_(e)(Q_(10)).However,little is known about the patterns and controlling factors of Q_(10)on the plateau,impeding the comprehension of the intensity of terrestrial carbon-climate feedbacks for these sensitive and vulnerable ecosystems.Here,we synthesized and analyzed multiyear observations from 14 sites to systematically compare the spatiotemporal variations of Q_(10)values in diverse climate zones and ecosystems,and further explore the relationships between Q_(10)and environmental factors.Moreover,structural equation modeling was utilized to identify the direct and indirect factors predicting Q_(10)values during the annual,growing,and non-growing seasons.The results indicated that the estimated Q_(10)values were strongly dependent on temperature,generally,with the average Q_(10)during different time periods increasing with air temperature and soil temperature at different measurement depths(5 cm,10 cm,20 cm).The Q_(10)values differentiated among ecosystems and climatic zones,with warming-induced Q_(10)declines being stronger in colder regions than elsewhere based on spatial patterns.NDVI was the most cardinal factor in predicting annual Q_(10)values,significantly and positively correlated with Q_(10).Soil temperature(Ts)was identified as the other powerful predictor for Q_(10),and the negative Q_(10)-Ts relationship demonstrates a larger terrestrial carbon loss potentiality in colder than in warmer regions in response to global warming.Note that the interpretations of the effect of soil moisture on Q_(10)were complicated,reflected in a significant positive relationship between Q_(10)and soil moisture during the growing season and a strong quadratic correlation between the two during the annual and non-growing season.These findings are conducive to improving our understanding of alpine grassland ecosystem carbon-climate feedbacks under warming climates. 展开更多
关键词 carbon cycle eddy covariance measurements ecosystem respiration Q_(10)value Tibetan Plateau climate change
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How Sense of Ritual in Tourism Impacts Tourists’Co-Creation of Tourism Experience Values:A Study Based on the Theory of Value Co-Creation
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作者 Yi Min Zhang Guangyu Sun Genjin 《Contemporary Social Sciences》 2024年第2期67-84,共18页
Establishing a sense of ritual within tourism consumption scenarios offers tourists the opportunity for interactive engagement.Drawing upon the value co-creation theory,this study constructed an influence mechanism mo... Establishing a sense of ritual within tourism consumption scenarios offers tourists the opportunity for interactive engagement.Drawing upon the value co-creation theory,this study constructed an influence mechanism model to examine tourists'active engagement in the process of co-creating tourism experience values.It employed Partial Least Squares Structural Equation Modeling(PLS-SEM)to empirically test the proposed hypotheses.The findings demonstrate that the model constructed in the present study exhibits robust reliability,validity,and explanatory power.The perception of the sense of ritual in tourism exerts a significant positive influence on tourists’co-creation of tourism experience values,thereby significantly enhancing both the communitas and flow experienced by tourists during their travels.Moreover,such communitas and flow can mediate the influence of the sense of ritual in tourism on tourists’co-creation of tourism experience values.This study contributes to advancing the current research on tourists’co-creation of tourism experience values and the sense of ritual in tourism,thereby providing theoretical foundations for cultivating a sense of ritual within tourism consumption scenarios. 展开更多
关键词 sense of ritual in tourism tourists’co-creation of tourism experience values theory of value co-creation theory of Interaction Ritual Chains
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Multi-scenario Simulation of the Impact of Land Use Change on the Ecosystem Service Value in the Suzhou-Wuxi-Changzhou Metropolitan Area,China
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作者 WANG Bin HU Chunguang ZHANG Yushuo 《Chinese Geographical Science》 SCIE CSCD 2024年第1期79-92,共14页
As the most economically developed metropolitan area in China’s Yangtze River Delta,the rapid changing land use patterns of Suzhou-Wuxi-Changzhou(Su-Xi-Chang) metropolitan area have profound impacts on the ecosystem ... As the most economically developed metropolitan area in China’s Yangtze River Delta,the rapid changing land use patterns of Suzhou-Wuxi-Changzhou(Su-Xi-Chang) metropolitan area have profound impacts on the ecosystem service value(ESV).Based on the patterns of land use change and the ESV change in Su-Xi-Chang metropolitan area from 2000 to 2020,we set up four scenarios:natural development scenario,urban development scenario,arable land protection scenario and ecological protection scenario,and simulated the impact of land use changes on the ESV in these scenarios.The results showed that:1) the area of built-up land in the Su-XiChang metropolitan area increased significantly from 2000 to 2020,and the area of other types of land decreased.Arable land underwent the highest transfer-out area,and was primarily converted into built-up land.The total ESV of Su-Xi-Chang metropolitan area increased initially then declined from 2000–2020,and the value of almost all individual ecosystem services decreased.2) Population density,GDP per area,night lighting intensity,and road network density can negatively impact the ESV.3) The total ESV loss under the natural development and urban development scenarios was high,and the expansion of the built-up land and the drastic shrinkage of the arable land contributed to the ESV decline under both scenarios.The total ESV under arable land protection and ecological protection scenarios increases,and therefore these scenarios are suitable for future land use optimization in Su-Xi-Chang.This study could provide a certain reference for land use planning and allocation,and offer guidance for the rational allocation of land resources. 展开更多
关键词 multiple scenarios land use simulation ecosystem service value(ESV) Patch-Generating Land Use Simulation(PLUS)model Suzhou-Wuxi-Changzhou(Su-Xi-Chang)metropolitan area
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Community Perception of Riparian Corridors Ecosystem Services and Implications for Environmental Education in Upper Oueme Catchment in Benin, West Africa
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作者 Socrate Mercator Dossou Kinnoumè Serge Adomou +1 位作者 Gérard Nounagnon Gouwakinnou Thierry Dèhouégnon Houéhanou 《Open Journal of Ecology》 2024年第2期125-147,共23页
The assessment of the local community perception of the value of riparian corridors is relevant to understand their attitude towards the conservation of such ecosystem. We conducted a semi-structured survey on the per... The assessment of the local community perception of the value of riparian corridors is relevant to understand their attitude towards the conservation of such ecosystem. We conducted a semi-structured survey on the perception and importance attributed to the ecosystem services (ESs) provided by riparian corridors in 368 households across 70 villages located in a buffer zone of 5 km of servitude around the permanent rivers of the Upper Oueme watershed in Benin. We found that local communities easily reported provisioning and cultural ESs than regulating and supporting ones, indicating their misunderstanding of the main role of riparian corridor. Moreover, the supply of cropping areas was perceived as the most important ES. Educated respondents and high-income households had more knowledge of regulating ESs and supporting ESs, respectively. Overall, the highly perceived importance of the provision of cropping areas indicates a potential risk of agricultural encroachment of riparian corridors. We suggest the consideration of the current local perception of riparian corridor’s role in designing a sound environmental education aiming at the change of local population’s perception. This perception shift will promote a sustainable management of the riparian corridors. 展开更多
关键词 Local Knowledge Direct Use Value Soil Formation Migration Importance Value BENIN
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A Study on the Values and Strategies of English Picture Book Reading for Improving Pupils’ English Reading Literacy
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作者 MAI Yuxuan 《Sino-US English Teaching》 2024年第3期120-126,共7页
Reading is one of the core skills in English learning.It is indispensable for EFL learners to develop good English reading literacy in primary schools.English picture books are consistent with pupils’cognitive and th... Reading is one of the core skills in English learning.It is indispensable for EFL learners to develop good English reading literacy in primary schools.English picture books are consistent with pupils’cognitive and thinking modes,which is valuable to improve their English reading literacy.However,at present,most Chinese pupils have some problems in English reading.The paper aims at analyzing the current problems in Chinese pupils’English reading and digging out the values and strategies of English picture book reading,so as to stimulate their reading interests,cultivate their intercultural awareness,and improve their English reading literacy. 展开更多
关键词 English reading literacy English picture book reading values STRATEGIES
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Sustainability Assessment of Banana (Musa spp.) Yield Gap Reduction through Value Chain Development Interventions in Smallholder Farming Systems in Manicaland, Zimbabwe
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作者 Mthintwa Tawanda Hove Hlamalani Ngwenya Johan Van Niekerk 《Agricultural Sciences》 2024年第8期962-992,共31页
This study evaluated the effectiveness of donor supported agricultural value chain development projects in sustainably narrowing yield gaps for banana smallholder farmer producers in Manicaland, Zimbabwe. The study us... This study evaluated the effectiveness of donor supported agricultural value chain development projects in sustainably narrowing yield gaps for banana smallholder farmer producers in Manicaland, Zimbabwe. The study used a mixed methods research design that relied on farmers records for the quantitative analysis and focus group discussion and in-depth interviews for key experts for the qualitative aspects. A mix of regression analysis, t-tests, Pearsons’s correlation and analysis of variance statistical methods were used for the quantitative analysis while thematic response analysis was used for the qualitative engagements. The findings showed that by the end of the activity, the project had successfully narrowed the banana yield gaps to 18.66 tons per hectare working with a potential yield base of 40 tons. However, 5 years after the project closure the yield gap had fallen to 24.7 tons indicating a lack of sustainability of yield gap reduction. However, the yield gap slump does not override the fact that farmers on average were still able to sell approximately 5 tons per every 6 months after 5 years from the project closure which is beyond any poverty threshold. This suggests genuine upward economic mobility. Additionally, in analyzing what factors had the greatest influence on yield gap reduction, the access to fertilizer ranked highest where genetics, irrigation and improved agronomy followed in that respective order. The study further showed that farmers who receive value chain development support whilst at an already commercialized state tend to maintain productivity thresholds higher in comparison to those who are at a pre commercial state. This is evidenced by the fact that the pre commercial farmers had a yield reduction of 30.83 percent after 5 years of the project closure whereas the former realized a productivity growth of 7.84%. In conclusion, whilst the intervention was successful in transitioning farmers out of poverty, more investment should be made towards transitioning smallholder farmers to integrated soil fertility management practices and improvement of agronomic efficiency through stronger on field collaboration between research institutions, the government and development institutions. 展开更多
关键词 Yield Gap Value Chain Development Soil Health Varietal Replacement Rate Sustainability and Economic Mobility
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Spatiotemporal Evolution of Ecosystem Service Value in Caohai National Nature Reserve
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作者 Denghong HUANG Zhenzhen ZHANG Jintong REN 《Meteorological and Environmental Research》 2024年第2期14-21,共8页
Wetland ecosystems are important regulators of global climate change.Studying the spatiotemporal changes and driving mechanisms of their ecosystem service values(ESV)is beneficial for the sustainable development of we... Wetland ecosystems are important regulators of global climate change.Studying the spatiotemporal changes and driving mechanisms of their ecosystem service values(ESV)is beneficial for the sustainable development of wetlands.This paper uses the equivalent factor method,based on land use changes,to reveal the spatiotemporal evolution of the ecosystem service value in the Caohai National Nature Reserve(CNNR).The results show the following:①from 2000 to 2020,there was a significant decrease in the core zone s arable land area,with an increase in forest and water areas.Construction land mainly increased in the experimental area,and the grassland area showed a fluctuating change of first increasing and then decreasing;②in 2000,2010,and 2020,the ecosystem service value of the study area was 302 million,296 million,and 325 million yuan,respectively,showing a trend of fluctuating growth,with the value of wetland ecosystems playing a dominant role;③regulatory services are the main contributors to the ecosystem service value in the study area,with a contribution rate of 60%.Hydrological regulation is the ecosystem function with the highest value in wetland ecosystem services,contributing more than 35%to the ESV in all three periods;④in terms of spatial distribution,the core zone s ecosystem service value is dominant.Looking at the total ecosystem service value of the region,the core zone>the experimental area>the buffer zone.In terms of ESV per unit area,the core zone(89000 yuan/hm^(2))is significantly higher than the buffer zone(39100 yuan/hm^(2))and the experimental area(15800 yuan/hm^(2)).The study can provide a basis for research and spatial management of ecosystem services in wetland ecosystems and nature reserves. 展开更多
关键词 Ecosystem service value(ESV) Equivalent factor method Land use change Wetland ecosystem CNNR
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Exploration of Curriculum Ideology and Politics Integrating Medical Humanities Cultivation Model to Enhance Medical Core Values
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作者 Wenjuan Ni Ranhao Li +1 位作者 Yaqing Guo Wei Wang 《Journal of Contemporary Educational Research》 2024年第5期1-7,共7页
Purpose:To explore the application effect of the cultivation mode of Curriculum Ideology and Political Integration of Medical Humanities to enhance the core values of medicine in the clinical internship stage of medic... Purpose:To explore the application effect of the cultivation mode of Curriculum Ideology and Political Integration of Medical Humanities to enhance the core values of medicine in the clinical internship stage of medical students.Methods:Students in the clinical internship stage of the First Affiliated Hospital of Baotou Medical College were selected,and a total of 156 students in one random class in each grade were taken as the observation group and received the integration cultivation mode;148 students were taken as the control group and employed the traditional mode.The teaching effect of interns in the two groups was analyzed.Results:The teaching performance of students in both groups after clinical internship teaching was improved compared with that before admission;the teaching performance,teaching effect,teaching evaluation,and teaching satisfaction of the observation group were higher than that of the control group.Conclusion:The integration of the medical humanities training model with curriculum ideology and politics in the clinical internship of medical students is conducive to the improvement of teaching performance,teaching evaluation,teaching satisfaction of teachers and students,and the development and improvement of core values of medical students,which is of good value for teaching application. 展开更多
关键词 Curriculum ideology and politics Medical humanities Medical students Core values Clinical internship
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Approximation Maintenance When Adding a Conditional Value in Set-Valued Ordered Decision Systems
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作者 Xiaoyu Wang Yuebin Su 《Open Journal of Applied Sciences》 2024年第2期411-424,共14页
The integration of set-valued ordered rough set models and incremental learning signify a progressive advancement of conventional rough set theory, with the objective of tackling the heterogeneity and ongoing transfor... The integration of set-valued ordered rough set models and incremental learning signify a progressive advancement of conventional rough set theory, with the objective of tackling the heterogeneity and ongoing transformations in information systems. In set-valued ordered decision systems, when changes occur in the attribute value domain, such as adding conditional values, it may result in changes in the preference relation between objects, indirectly leading to changes in approximations. In this paper, we effectively addressed the issue of updating approximations that arose from adding conditional values in set-valued ordered decision systems. Firstly, we classified the research objects into two categories: objects with changes in conditional values and objects without changes, and then conducted theoretical studies on updating approximations for these two categories, presenting approximation update theories for adding conditional values. Subsequently, we presented incremental algorithms corresponding to approximation update theories. We demonstrated the feasibility of the proposed incremental update method with numerical examples and showed that our incremental algorithm outperformed the static algorithm. Ultimately, by comparing experimental results on different datasets, it is evident that the incremental algorithm efficiently reduced processing time. In conclusion, this study offered a promising strategy to address the challenges of set-valued ordered decision systems in dynamic environments. 展开更多
关键词 Information systems Rough Set Attribute Value Incremental Method
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Changes in Grassland Ecosystem Service Values in the Three-River Headwaters Region,China 被引量:3
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作者 赖敏 吴绍洪 +1 位作者 尹云鹤 潘韬 《Agricultural Science & Technology》 CAS 2013年第4期654-660,共7页
[Method] This study aimed to assess the changes in grassland ecosystem Service values in the Three-River Headwaters Region of China, the source of the Yangtze, Yellow (Huang He) and Lantsang (Mekong) rivers. [Meth... [Method] This study aimed to assess the changes in grassland ecosystem Service values in the Three-River Headwaters Region of China, the source of the Yangtze, Yellow (Huang He) and Lantsang (Mekong) rivers. [Method] Biophysical values of four services were monetized within the region, including water regulation, air quality regulation, climate regulation and soil conservation. [Result] The total ESVs were 884.97×10^8 Yuan, 1 302.06×10^8 Yuan and 1 299.49×10^8 Yuan in 2000, 2005 and 2008, respectively. The amount of value per unit area experienced a steep increase from 2000 to 2005(18.10×10^4 Yuan/km2), and then remained almost unchanged from 2005 to 2008 (-0.31×10^4 Yuan/km2). The ESV tended to decline from the southeastern to the northwestern. ESV in the eastern and central part increased faster than that in the south-central and western part of the TRHR from 2000 to 2008. It could be seen that the ecosystem condition of grassland in the TRHR improved signifi- cantly over the study period of 2000-2008. [Conelusion] The results provided good information to assess the effectiveness of current ecological protection measures in the TRHR and support regional sustainable management policies. 展开更多
关键词 Grassland ecosystem Ecosystem service value (ESV) VALUATION The Three-River Headwaters Region (TRHR)
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Using a Spatial Convolution Method to Estimate Ecosystem Services Values at Regional Level: a Case Study in Northeast China 被引量:1
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作者 何英彬 唐华俊 +4 位作者 陈佑启 姚艳敏 杨鹏 李建平 辛晓平 《Journal of Landscape Research》 2010年第7期1-6,共6页
Since the introduction of the concept, studies on valuation of ecosystem services have been overwhelming, in cognizance of its great significance. In this article, the authors took Northeast China as the study area an... Since the introduction of the concept, studies on valuation of ecosystem services have been overwhelming, in cognizance of its great significance. In this article, the authors took Northeast China as the study area and applied the published coefficients for the world by Costanza to calculate the ecosystem services values through a spatial convolution method. The convolution analysis was done with a square processor with 5×5 neighborhood cells. The results showed that the ecosystem services value for the study area in the year 2003 was US$44 990 million which is US$89 million less than the value without operation, and the main contributions for that decrease were from water bodies, wetlands and estuaries. It is expected that this article can attract more interest to explore this field adopting geographic methods. 展开更多
关键词 ECOsystem services values GEOGRAPHICAL SPATIAL convolution method Estimation SPATIAL HETEROGENEITY BIOMES
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Forest Ecosystem Services and Their Values in Beijing 被引量:21
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作者 XIE Gaodi LI Wenhua +6 位作者 XIAO Yu ZHANG Biao LU Chunxia AN Kai WANG Jixing XU Kang WANG Jinzeng 《Chinese Geographical Science》 SCIE CSCD 2010年第1期51-58,共8页
As the most important ecosystem in Beijing, the forest supports a lot of ecosystem services to local and around communities, which plays a key role in the maintenance of urban ecological security.However, the valuatio... As the most important ecosystem in Beijing, the forest supports a lot of ecosystem services to local and around communities, which plays a key role in the maintenance of urban ecological security.However, the valuation on the forest ecosystem services based on regional scale could not provide precise and reasonable values for forestry sector management.In this study, we estimated the magnitudes and economic values of the forest ecosystem services in Beijing at sublot level.The economic value of forest ecosystem services in Beijing was estimated to be 19 339.71×10 6 yuan(RMB) in 2004.Among all the ecosystem services indicators we estimated in this study, only fruit, timber and part of the recreation(which only include the tourism income from the forest parks and scenic areas, but not include that from other forest types) were measured in the social economic system.As estimated in this study, more than 82.19% of the economic value of forest ecosystem services could not be measured in the socio-economic statistical system.The importance of forest ecosystem services in Beijing to human welfare was underestimated by the socio-economic system.Therefore, the policies about the eco-compensation of forest ecosystem services should be established to maintain the sustainable supply of the forest ecosystem services in Beijing. 展开更多
关键词 FOREST ecosystem service economic value BEIJING
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Estimates of loss in ecosystem service values of Songnen plain from 1980 to 2000 被引量:13
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作者 WANGZongmin ZHANGBai +2 位作者 ZHANGShuqin SONGKaishan DUANHongtao 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期80-86,共7页
Ecosystem services are premises for human beings to exist and develop in the world, and it is of importance to study effects of land use change on ecosystem functions. Songnen plain, located in Northeast China, is one... Ecosystem services are premises for human beings to exist and develop in the world, and it is of importance to study effects of land use change on ecosystem functions. Songnen plain, located in Northeast China, is one of the national key bases for agricultural production. Because there were remarkable variations in land use in recent years, it can supply specific foundation for protection and restoration of regional eco-environment to explore changes in its values of ecosystem services. This study aims to qualify long-term changes in land use of Songnen plain from 1980 to 2000, and to explore the impact of land use change on ecosystem services. With 2-period land use data using RS and GIS, this paper analyzed changes in land use and in ecosystem service values using the ecosystem service value coefficients (VC) put forward by Costanza et al. Results showed that from 1980 to 2000, area of rangeland, water area and wetlands and area of cropland decreased, but urban area and unused land increased. Due to cropland's comparatively low VC and comparatively high VC of wetlands and water area, increment in cultivated land could not offset the total decrement in regional ecosystem service values because of the decrease in area of wetlands and water area. Meanwhile, city sprawl has also led to loss of ecological values. Total ecosystem service values of the study area reduced dramatically, from 34,926.10×106$ to 31,744.54×106$ in the period 1980-2000. This represents a 9.11% net decline in annual value of ecosystem services in the study area. 展开更多
关键词 ecological values land use change ecosystem service Songnen plain
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Responses of Spatial-temporal Variation of Karst Ecosystem Service Values to Landscape Pattern in Northwest of Guangxi,China 被引量:6
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作者 ZHANG Mingyang WANG Kelin +1 位作者 LIU Huiyu ZHANG Chunhua 《Chinese Geographical Science》 SCIE CSCD 2011年第4期446-453,共8页
The responses of spatiotemporal variation of ecosystem service values (ESVs) to landscape pattern from 1985 to 2005 in a typical Karst area of the northwest Guangxi Zhuang Autonomous Region,China,were examined us-ing ... The responses of spatiotemporal variation of ecosystem service values (ESVs) to landscape pattern from 1985 to 2005 in a typical Karst area of the northwest Guangxi Zhuang Autonomous Region,China,were examined us-ing remote sensing and geographic information system techniques in this paper.The total ecosystem service values de-clined significantly from 1985 to 1990,and then increased slowly from 1990 to 2005,almost equaled to the 1985 level.The ecosystem service values tended to decline from the west to the east and from mountainous regions to peak-cluster depression areas in 1985,1990,2000 and 2005 respectively.During the period from 1985 to 2005,the ecosystem ser-vice values have increased in the middle and eastern parts of the study area.Landscape pattern indices,such as total area,largest patch index,contagion,aggregative index,effective mesh and proportion of like adjacencies,are significantly correlated with ecosystem service values.This suggests that ecosystem service values tend to increase with the growth of patch area and patch connectivity.However,there are negative correlations between ecosystem service values and landscape pattern indices,such as division index and patch richness.It indicates that ecosystem service values decrease with patch fragmentation and patch size shrinkage.The ecosystem conditions in the typical Karst area have been improved because of the control measures of rocky desertification.It is important to protect key landscape types,such as woodland,shrub and grassland,and to increase patch size and connectivity to avoid further fragmentation.Furthermore,it is necessary to reduce disturbances to ensure the growth of ecosystem service values and to facilitate the sustainable development in this region. 展开更多
关键词 landscape pattern ecosystem service values (ESVs) landscape indices KARST GUANGXI
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