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Latitudinal gradients of biodiversity and ecosystem services in protected and non-protected oak forest areas can inform climate smart conservation
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作者 Anders Forsman Johanna Sunde +1 位作者 Romana Salis Markus Franzen 《Geography and Sustainability》 CSCD 2024年第4期647-659,共13页
Adaptive governance of areas set aside for future protection of biodiversity,sustainable production,and recreation requires knowledge about whether and how effects of area protection are modulated by climate change an... Adaptive governance of areas set aside for future protection of biodiversity,sustainable production,and recreation requires knowledge about whether and how effects of area protection are modulated by climate change and redistribution of species.To investigate this,we compare biodiversity of plants(assessed using vegetation plots)and arthropods(collected with Malaise traps,analyzed using metabarcoding)and productivity(tree growth,determined using dendrochronology)in protected and non-protected oak(Quercus spp.)forests along a latitudinal gradient(55.6°N–60.8°N)in Sweden.We also compare historical,recent and projected future climate in the region.In contrast to established global latitudinal diversity gradients,species richness of plants and arthropods increased northwards,possibly reflecting recent climate-induced community redistributions,but neither was higher in protected than in non-protected areas,nor associated with contemporary ground temperature.Species composition of arthropods also did not differ between protected and non-protected areas.Arthropod biomass increased with latitude,suggesting that the magnitude of cascading effects mediated via their roles as pollinators,herbivores,and prey for other trophic levels,varies geographically and will change with a moving climate.Annual growth rate of oaks(an ecosystem service in the form of biomass increase and carbon sequestration)was independent of latitude and did not differ between protected and non-protected areas.Our findings question the efficacy of contemporary designation and management of protected oak forests,and emphasize that development and implementation of modified climate smart conservation strategies is needed to safeguard ecosystem functioning,biodiversity,and recreational values of protected forest areas against future challenges. 展开更多
关键词 Biological diversity Conservation biology Decision making Forest ecosystems Global warming Species-richness gradients
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Relating estimates of wood properties of birch to stem form, age and species
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作者 Grace Jones Maria Ulan +2 位作者 Mateusz Liziniewicz Johan Lindeberg Stergios Adamopoulos 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期1-11,共11页
Birch has long suffered from a lack of active forest management,leading many researchers to use mate-rial without a detailed management history.Data collected from three birch(Betula pendula Roth,B.pubescens Ehrh.)sit... Birch has long suffered from a lack of active forest management,leading many researchers to use mate-rial without a detailed management history.Data collected from three birch(Betula pendula Roth,B.pubescens Ehrh.)sites in southern Sweden were analyzed using regression analysis to detect any trends or differences in wood proper-ties that could be explained by stand history,tree age and stem form.All sites were genetics trials established in the same way.Estimates of acoustic velocity(AV)from non-destructive testing(NDT)and predicted AV had a higher correlation if data was pooled across sites and other stem form factors were considered.A subsample of stems had radial profiles of X-ray wood density and ring width by year created,and wood density was related to ring number from the pith and ring width.It seemed likely that wood density was negatively related to ring width for both birch species.Linear models had slight improvements if site and species were included,but only the youngest site with trees at age 15 had both birch species.This paper indicated that NDT values need to be considered separately,and any predictive models will likely be improved if they are specific to the site and birch species measured. 展开更多
关键词 Acoustic velocity Non-destructive testing Predictive models Regression analysis Wood density
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Refinement of Adaptive Dynamical Simulation of Quantum Mechanical Double Slit Interference Phenomenon
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作者 Tadashi Ando Andrei Khrennikov Ichiro Yamato 《Journal of Modern Physics》 2024年第3期239-249,共11页
We applied adaptive dynamics to double slit interference phenomenon using particle model and obtained partial successful results in our previous report. The patterns qualitatively corresponded well with experiments. S... We applied adaptive dynamics to double slit interference phenomenon using particle model and obtained partial successful results in our previous report. The patterns qualitatively corresponded well with experiments. Several properties such as concave single slit pattern and large influence of slight displacement of the emission position were different from the experimental results. In this study we tried other slit conditions and obtained consistent patterns with experiments. We do not claim that the adaptive dynamics is the principle of quantum mechanics, but the present results support the probability of adaptive dynamics as the candidate of the basis of quantum mechanics. We discuss the advantages of the adaptive dynamical view for foundations of quantum mechanics. 展开更多
关键词 Double Slit Interference Adaptive Dynamics Quantum Mechanics Particle Model Simulation
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湘中安化黑色页岩土壤玉米的元素地球化学分析 被引量:4
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作者 杨克苏 彭渤 +4 位作者 刘茜 余昌训 唐晓燕 谢淑容 谭长银 《矿物岩石地球化学通报》 CAS CSCD 北大核心 2012年第3期236-248,共13页
利用等离子质谱(ICP-MS)等分析技术,对产于安化东坪、烟溪黑色页岩土壤上的玉米进行元素地球化学分析。结果表明:尽管东坪、烟溪黑色页岩土壤重金属元素富集的程度及其元素组合特征明显不同,但生长在其上的玉米有相似的主量元素和重金... 利用等离子质谱(ICP-MS)等分析技术,对产于安化东坪、烟溪黑色页岩土壤上的玉米进行元素地球化学分析。结果表明:尽管东坪、烟溪黑色页岩土壤重金属元素富集的程度及其元素组合特征明显不同,但生长在其上的玉米有相似的主量元素和重金属元素的富集特征。玉米中Cd、Cr、Sc、Tl、Zn等重金属相对富集,以Cd的富集尤为明显;而Ba、Co、Cu、Fe、Mo、Ni、Pb、Sb、U、V等重金属相对亏损。黑色页岩土壤重金属污染的环境地球化学效应表现为Sc、Cr、Cd、Tl等生物毒性重金属元素在玉米中富集,而Ba、V、Co、Ni、Mo、Rb、Sr等生物必需微量金属在玉米中亏损。 展开更多
关键词 重金属 玉米 黑色页岩主壤 湘申
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湘江下游入湖河段河床沉积物人为源重金属比例的估算 被引量:5
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作者 全美杰 彭渤 +6 位作者 鲍志诚 张仁 徐婧喆 肖敏 谢淑容 唐晓燕 余昌训 《东华理工大学学报(自然科学版)》 CAS 2013年第2期152-160,共9页
以湘江下游河床沉积物元素和Pb同位素地球化学分析结果为基础,利用元素分析法和Pb同位素比值法对沉积物中人为源重金属比例进行定量计算。元素分析法估算得到重金属Bi,Cu,Pb,Zn,Cd,Mn,Sn,Sb等的人为源比例依次为92%~97%,50%~70%,77%~... 以湘江下游河床沉积物元素和Pb同位素地球化学分析结果为基础,利用元素分析法和Pb同位素比值法对沉积物中人为源重金属比例进行定量计算。元素分析法估算得到重金属Bi,Cu,Pb,Zn,Cd,Mn,Sn,Sb等的人为源比例依次为92%~97%,50%~70%,77%~85%,58%~85%,89%~98%,60%~82%,85%~93%,78%~89%。铅同位素比值法估算得到沉积物中人为源Pb的比例在58%~60%之间,较元素分析法计算得到的人为源铅低25%~29%。依铅同位素法估算结果对元素分析法估算结果进行校正,得到重金属Bi,Cu,Pb,Zn,Cd,Mn,Sn,Sb等的人为源比例平均值依次为69%~73%、37%~53%、58%~64%、44%~64%、67%~73%、45%~61%、63%~70%、58%~67%。 展开更多
关键词 人为源重金属比例 元素分析法 Pb同位素法 沉积物重金属污染 湘江
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湘西柑子坪黑色页岩土壤地球化学分析
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作者 徐婧喆 彭渤 +7 位作者 杨广 余昌训 唐晓燕 谭长银 谢淑容 鲍志诚 全美杰 肖敏 《矿物学报》 CAS CSCD 北大核心 2011年第S1期724-725,共2页
近年来,黑色页岩风化的地球化学研究受到学界的重视。这是因为富含有机质和硫化物矿物(主要为黄铁矿)的黑色页岩暴露地表极易被风化分解,淋滤释出重金属元素(Littke et al.,1991;Peucker-Ehrenbrink,2000;Peng et al.,2004),而影响地表... 近年来,黑色页岩风化的地球化学研究受到学界的重视。这是因为富含有机质和硫化物矿物(主要为黄铁矿)的黑色页岩暴露地表极易被风化分解,淋滤释出重金属元素(Littke et al.,1991;Peucker-Ehrenbrink,2000;Peng et al.,2004),而影响地表(水、土壤)环境(Peng et al.,2004;彭渤等,2005)。由于黑色页岩成岩物源条件、沉积环境等方面的差异,使得不同地区。 展开更多
关键词 黑色页岩 重金属元素 土壤样品 地球化学分析 地球化学特征 黄铁矿 地球化学研究 有机质 表层土壤 硫化物矿物
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Effects of rice straw on the cell viability, photosynthesis, and growth of Microcystis aeruginosa 被引量:5
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作者 苏文 Johannes A.HAGSTR?M +2 位作者 贾育红 卢亚萍 孔繁翔 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第1期120-129,共10页
Rice straw is supposed to be an environment-friendly biomaterial for inhibiting the growth of harmful blooms of the cyanobacterium Microcystis aeruginosa. However, its potential mechanism is not well known. To explore... Rice straw is supposed to be an environment-friendly biomaterial for inhibiting the growth of harmful blooms of the cyanobacterium Microcystis aeruginosa. However, its potential mechanism is not well known. To explore this mechanism, the growth, cell viability(esterase activity, membrane potential, and membrane integrity), photosynthesis, and cell size of M. aeruginosa were determined using fl ow cytometry and Phyto-PAM after exposure to rice straw extracts(RSE). The results show that doses from 2.0 to 10.0 g/L of RSE effi ciently inhibited the alga for 15 days, while the physiologic and morphologic responses of the cyanobacteria were time-dependent. RSE interfered with the cell membrane potential, cell size, and in vivo chlorophyll- a fl uorescence on the fi rst day. After 7 days of exposure, RSE was transported into the cytosol, which disrupted enzyme activity and photosynthesis. The cyanobacteria then started to repair its physiology(enzyme activity, photosynthesis) and remained viable, suggesting that rice straw act as an algistatic agent. 展开更多
关键词 esterase activity membrane potential Phyto-PAM rice straw MICROCYSTIS flow cytometry
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Automatic Classification of Swedish Metadata Using Dewey Decimal Classification:A Comparison of Approaches 被引量:2
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作者 Koraljka Golub Johan Hagelback Anders Ardo 《Journal of Data and Information Science》 CSCD 2020年第1期18-38,共21页
Purpose:With more and more digital collections of various information resources becoming available,also increasing is the challenge of assigning subject index terms and classes from quality knowledge organization syst... Purpose:With more and more digital collections of various information resources becoming available,also increasing is the challenge of assigning subject index terms and classes from quality knowledge organization systems.While the ultimate purpose is to understand the value of automatically produced Dewey Decimal Classification(DDC)classes for Swedish digital collections,the paper aims to evaluate the performance of six machine learning algorithms as well as a string-matching algorithm based on characteristics of DDC.Design/methodology/approach:State-of-the-art machine learning algorithms require at least 1,000 training examples per class.The complete data set at the time of research involved 143,838 records which had to be reduced to top three hierarchical levels of DDC in order to provide sufficient training data(totaling 802 classes in the training and testing sample,out of 14,413 classes at all levels).Findings:Evaluation shows that Support Vector Machine with linear kernel outperforms other machine learning algorithms as well as the string-matching algorithm on average;the string-matching algorithm outperforms machine learning for specific classes when characteristics of DDC are most suitable for the task.Word embeddings combined with different types of neural networks(simple linear network,standard neural network,1 D convolutional neural network,and recurrent neural network)produced worse results than Support Vector Machine,but reach close results,with the benefit of a smaller representation size.Impact of features in machine learning shows that using keywords or combining titles and keywords gives better results than using only titles as input.Stemming only marginally improves the results.Removed stop-words reduced accuracy in most cases,while removing less frequent words increased it marginally.The greatest impact is produced by the number of training examples:81.90%accuracy on the training set is achieved when at least 1,000 records per class are available in the training set,and 66.13%when too few records(often less than A Comparison of Approaches100 per class)on which to train are available—and these hold only for top 3 hierarchical levels(803 instead of 14,413 classes).Research limitations:Having to reduce the number of hierarchical levels to top three levels of DDC because of the lack of training data for all classes,skews the results so that they work in experimental conditions but barely for end users in operational retrieval systems.Practical implications:In conclusion,for operative information retrieval systems applying purely automatic DDC does not work,either using machine learning(because of the lack of training data for the large number of DDC classes)or using string-matching algorithm(because DDC characteristics perform well for automatic classification only in a small number of classes).Over time,more training examples may become available,and DDC may be enriched with synonyms in order to enhance accuracy of automatic classification which may also benefit information retrieval performance based on DDC.In order for quality information services to reach the objective of highest possible precision and recall,automatic classification should never be implemented on its own;instead,machine-aided indexing that combines the efficiency of automatic suggestions with quality of human decisions at the final stage should be the way for the future.Originality/value:The study explored machine learning on a large classification system of over 14,000 classes which is used in operational information retrieval systems.Due to lack of sufficient training data across the entire set of classes,an approach complementing machine learning,that of string matching,was applied.This combination should be explored further since it provides the potential for real-life applications with large target classification systems. 展开更多
关键词 LIBRIS Dewey Decimal Classification Automatic classification Machine learning Support Vector Machine Multinomial Naive Bayes Simple linear network Standard neural network 1D convolutional neural network Recurrent neural network Word embeddings String matching
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Impacts of silicon on biogeochemical cycles of carbon and nutrients in croplands 被引量:2
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作者 LI Zi-chuan SONG Zhao-liang +5 位作者 YANG Xiao-min SONG A-lin YU Chang-xun WANG Tao XIA Shao-pan LIANG Yong-chao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第10期2182-2195,共14页
Crop harvesting and residue removal from croplands often result in imbalanced biogeochemical cycles of carbon and nutrients in croplands, putting forward an austere challenge to sustainable agricultural production. As... Crop harvesting and residue removal from croplands often result in imbalanced biogeochemical cycles of carbon and nutrients in croplands, putting forward an austere challenge to sustainable agricultural production. As a beneficial element, silicon(Si) has multiple eco-physiological functions, which could help crops to acclimatize their unfavorable habitats. Although many studies have reported that the application of Si can alleviate multiple abiotic and biotic stresses and increase biomass accumulation, the effects of Si on carbon immobilization and nutrients uptake into plants in croplands have not yet been explored. This review focused on Si-associated regulation of plant carbon accumulation, lignin biosynthesis, and nutrients uptake, which are important for biogeochemical cycles of carbon and nutrients in croplands. The tradeoff analysis indicates that the supply of bioavailable Si can enhance plant net photosynthetic rate and biomass carbon production(especially root biomass input to soil organic carbon pool), but reduce shoot lignin biosynthesis. Besides, the application of Si could improve uptake of most nutrients under deficient conditions, but restricts excess uptake when they are supplied in surplus amounts. Nevertheless, Si application to crops may enhance the uptake of nitrogen and iron when they are supplied in deficient to luxurious amounts, while potassium uptake enhanced by Si application is often involved in alleviating salt stress and inhibiting excess sodium uptake in plants. More importantly, the amount of Si accumulated in plant positively correlates with nutrients release during the decay of crop biomass, but negatively correlates with straw decomposability due to the reduced lignin synthesis. The Si-mediated plant growth and litter decomposition collectively suggest that Si cycling in croplands plays important roles in biogeochemical cycles of carbon and nutrients. Hence, scientific Si management in croplands will be helpful for maintaining sustainable development of agriculture. 展开更多
关键词 SILICON CROPLAND biogeochemical cycle biomass carbon NUTRIENT
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Estimation of a basal area growth model for individual trees in uneven-aged Caspian mixed species forests 被引量:1
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作者 Zohreh Mohammadi Soleiman Mohammadi Limaei +1 位作者 Peter Lohmander Leif Olsson 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1205-1214,共10页
The aim of this study was to estimate a basal area growth model for individual trees in uneven-aged Caspian forests.A survey was conducted in order to find a natural forest without any harvesting activities,a so call... The aim of this study was to estimate a basal area growth model for individual trees in uneven-aged Caspian forests.A survey was conducted in order to find a natural forest without any harvesting activities,a so called 'untouched forest' and an area was selected from the Iranian Caspian forest.Three sample plots in the same aspect and of the same forest type were selected.In each plot,total tree height,diameter at breast height,distance of neighbor trees and azimuth were measured.Thirty trees were selected and drilled with increment borer to determine the increment model.Regression analysis was used to estimate the growth model.Results show that,for individual trees,there is a significant nonlinear relationship between the annual basal area increment,as the dependent variable,and the basal area.The results also show that the basal area of competing trees has a positive influence on growth.That the increment is higher with more competing neighboring trees is possibly because plots with higher volume per hectare and more competition,most likely also have higher site index or better soil or better site productivity than the plot with lower volume per hectare. 展开更多
关键词 Basal area increment Diameter growth Regression analysis Caspian forests
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Why Open Government Data? The Case of a Swedish Municipality 被引量:1
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作者 Koraljka Golub Arwid Lund 《Journal of Data and Information Science》 CSCD 2021年第1期120-138,共19页
Purpose: The purpose of this exploratory study is to provide modern local governments with potential use cases for their open data, in order to help inform related future policies and decision-making. The concrete con... Purpose: The purpose of this exploratory study is to provide modern local governments with potential use cases for their open data, in order to help inform related future policies and decision-making. The concrete context was that of the Vaxjo municipality located in southeastern Sweden.Design/methodology/approach: The methodology was two-fold: 1) a survey of potential end users(n=151) from a local university;and, 2) analysis of survey results using a theoretical model regarding local strategies for implementing open government data.Findings: Most datasets predicted to be useful were on: sustainability and environment;preschool and school;municipality and politics. The use context given is primarily research and development, informing policies and decision making;but also education, informing personal choices, informing citizens and creating services based on open data. Not the least, the need for educating target user groups on data literacy emerged. A tentative pattern comprising a technical perspective on open data and a social perspective on open government was identified. Research limitations: In line with available funding, the nature of the study was exploratory and implemented as an anonymous web-based survey of employees and students at the local university. Further research involving(qualitative) surveys with all stakeholders would allow for creating a more complete picture of the matter. Practical implications: The study determines potential use cases and use contexts for open government data, in order to help inform related future policies and decision-making.Originality/value: Modern local governments, and especially in Sweden, are faced with a challenge of how to make their data open, how to learn about which types of data will be most relevant for their end users and what will be different societal purposes. The paper contributes to knowledge that modern local governments can resort to when it comes to attitudes of local citizens to open government data in the context of an open government data perspective. 展开更多
关键词 Open data E-GOVERNMENT Open government
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A Semi-Supervised Approach for Aspect Category Detection and Aspect Term Extraction from Opinionated Text 被引量:1
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作者 Bishrul Haq Sher Muhammad Daudpota +2 位作者 Ali Shariq Imran Zenun Kastrati Waheed Noor 《Computers, Materials & Continua》 SCIE EI 2023年第10期115-137,共23页
The Internet has become one of the significant sources for sharing information and expressing users’opinions about products and their interests with the associated aspects.It is essential to learn about product revie... The Internet has become one of the significant sources for sharing information and expressing users’opinions about products and their interests with the associated aspects.It is essential to learn about product reviews;however,to react to such reviews,extracting aspects of the entity to which these reviews belong is equally important.Aspect-based Sentiment Analysis(ABSA)refers to aspects extracted from an opinionated text.The literature proposes different approaches for ABSA;however,most research is focused on supervised approaches,which require labeled datasets with manual sentiment polarity labeling and aspect tagging.This study proposes a semisupervised approach with minimal human supervision to extract aspect terms by detecting the aspect categories.Hence,the study deals with two main sub-tasks in ABSA,named Aspect Category Detection(ACD)and Aspect Term Extraction(ATE).In the first sub-task,aspects categories are extracted using topic modeling and filtered by an oracle further,and it is fed to zero-shot learning as the prompts and the augmented text.The predicted categories are the input to find similar phrases curated with extracting meaningful phrases(e.g.,Nouns,Proper Nouns,NER(Named Entity Recognition)entities)to detect the aspect terms.The study sets a baseline accuracy for two main sub-tasks in ABSA on the Multi-Aspect Multi-Sentiment(MAMS)dataset along with SemEval-2014 Task 4 subtask 1 to show that the proposed approach helps detect aspect terms via aspect categories. 展开更多
关键词 Natural language processing sentiment analysis aspect-based sentiment analysis topic-modeling POS tagging zero-shot learning
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The Health and Well-Being among Children with Diabetes and Low HbA1c—A Qualitative Study in Sweden 被引量:1
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作者 Lena Lendahls Ingrid Edvardsson 《Health》 2018年第5期551-564,共14页
Aims and objectives: To examine health and well-being, as well as the need for support among children and parents where the child has T1DM with low HbA1c (Introduction: Studies have shown that children with diabetes t... Aims and objectives: To examine health and well-being, as well as the need for support among children and parents where the child has T1DM with low HbA1c (Introduction: Studies have shown that children with diabetes type 1 (T1DM) rate their lives as worse than healthy peer ratings. In Sweden, views have been expressed that children, as well as their parents, feel pressurized by the diabetes teams to achieve low HbA1c values, which can lead to poorer mental health for the family. Design: A qualitative study. Methods: A consecutive sample of 11 children and their parents (one father, ten mothers) was interviewed together but individually guided by a semi structured interview guide. Interviews were analyzed using thematic content analysis. Results: Four main categories were consistent across children and their parents;1) attitude to the illness, 2) sadness about diabetes, 3) the importance of the social network, and 4) the importance of the diabetes team. Worries about hyperglycemia were more prominent than worries about hypoglycemia in both children and parents. A distinguishing feature of the interviewed children was that they were responsible, strict and targeted. Many of them were competitive and took part in various sports, even at a very advanced level. Conclusions: This study shows that children with low HbA1c values experience good health and good well-being. Family support, good planning, and high acceptance of their illness contributed to this. 展开更多
关键词 DIABETES CHILDREN HEALTH WELL-BEING LOW HBA1C Qualitative Study
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Limited Focus on the Use of Health Care by Elderly Migrants——A Literature Review 被引量:3
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作者 Katarina Hjelm Bjorn Albin 《Open Journal of Nursing》 2014年第6期465-473,共9页
Our premise for this literature review is the global demographic change caused by the world’s population living longer and becoming older, and extensive international migration leading to multicultural societies. Inc... Our premise for this literature review is the global demographic change caused by the world’s population living longer and becoming older, and extensive international migration leading to multicultural societies. Increasing age leads to health problems, often long-term or chronic, requiring investments in health care. Worse health and dissimilarities in pattern of morbidity/ mortality have been found in foreign-compared to Swedish-born persons, so it is reasonable to assume that this affects use of health care. The exploratory review focuses on elderly migrants’ (>65 years) use of healthcare. The databases Pub Med, EBSCO, CINAHL and ERIC were searched in 2000-2013. A limited number of studies were found;few had a comparative approach, most were from the USA, and focused on migrants from the former Soviet Union or countries in South-East Asia. A range of factors were identified that influence patterns of health care use: language fluency, ability to communicate, self-reported health status, prevalence of chronic disease, physical distance from care provision, availability of transport to reach care, cost of care, the health insurance system, cultural norms and values regarding different forms of care, level of education, and length of residence in the host country. Most studies treated health care from a general perspective and collected data from community and hospital settings, without analysing usage separately. Some studies indicated elderly migrants making use of health care less than other groups but the pattern is not unambiguous: other studies show that there is an overuse of health care. It is therefore difficult to show any particular pattern, or possible differences in use, regarding community versus in-patient care. Studies focusing on migrants’ actual use of health care are few and further research is needed, especially because elderly people form the largest group of users of health care and will be even larger in the future. 展开更多
关键词 Ageing ELDERLY MIGRANTS CONSUMPTION UTILISATION Health Care Health Resources
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Intensive Care Nurses’Experiences of Caring for Intubated Patients under Light Sedation:A Qualitative Study 被引量:1
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作者 Kajsa Backlund Karoline Persson Emina Hadziabdic 《Open Journal of Nursing》 2018年第7期473-484,共12页
Introduction: Previous studies have shown that a light sedation level is beneficial for intubated patients in the Intensive care unit (ICU). Aim: This study aimed to describe intensive care nurses’ experiences of car... Introduction: Previous studies have shown that a light sedation level is beneficial for intubated patients in the Intensive care unit (ICU). Aim: This study aimed to describe intensive care nurses’ experiences of caring for intubated patients under light sedation. Methods: This study was an explorative descriptive qualitative study. Data were collected from 12 intensive care nurses by three focus group interviews and analyzed using qualitative content analysis. Findings: Five categories emerged from the data: 1) the importance of verbal communication and the nurses’ presence, 2) feelings of frustration and heavy workload, 3) assessment of patients’ pain and anxiety, 4) the nurses’ desire for the development of guidelines, and 5) being inspired by the care. Conclusion: The study found that intensive care nurses were positive towards light sedation care but the organization of care did not support them as the patients cared for with light sedation treatments demanded their physical presence at patients’ bed site. 展开更多
关键词 Intensive Care Nurse Light Sedation Experiences CARING Focus Groups Qualitative Content Analysis
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Phenotype manipulation influences microhabitat choice in pygmy grasshoppers
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作者 Lena WENNERSTEN Einat KARPESTAM Anders FORSMAN 《Current Zoology》 SCIE CAS CSCD 2012年第3期392-400,共9页
The matching habitat choice hypothesis posits that individuals actively choose those microhabitats that best match their specific phenotype to maximize fitness. Despite the profound implications, matching habitat choi... The matching habitat choice hypothesis posits that individuals actively choose those microhabitats that best match their specific phenotype to maximize fitness. Despite the profound implications, matching habitat choice has not been unequivo- cally demonstrated. We conducted two experiments to examine the impact of pigmentation pattern in the color polymorphic pygmy grasshopper Tetrix subulata on habitat choice in a laboratory thermal mosaic arena. We found no behavioral differences in the thermal mosaic among pygmy grasshoppers belonging to either pale, intermediate or dark natural color morphs. However, af- ter manipulating the grasshoppers' phenotype, the utilization through time of warmer and colder parts of the arena was different for black-painted and white-painted individuals. White-painted individuals used warmer parts of the arena, at least during the ini- tial stage of the experiment. We conclude that microhabitat choice represents a form of behavioural plasticity. Thus, even if the choice itself is flexible and not genetically determined, it can still lead to spatial genetic structure in the population because the phenotypes themselves may be genetically mediated [Current Zoology 58 (3): 392--400, 2012]. 展开更多
关键词 Behavioral plasticity Color polymorphism Integrated phenotypes Microhabitat use TETRIX THERMOREGULATION
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The effect of climate factors on the size of forest wildfires(case study:Prague-East district,Czech Republic)
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作者 Zohreh Mohammadi Peter Lohmander +3 位作者 Jan Kašpar Roman Berčák Jaroslav Holuša Robert Marušák 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第4期1291-1300,共10页
This paper presents a new approach to identifying the climate variables that influence the size of the area burned by forest wildfires.Multiple linear regression was used in combination with nonlinear variable transfo... This paper presents a new approach to identifying the climate variables that influence the size of the area burned by forest wildfires.Multiple linear regression was used in combination with nonlinear variable transformations to determine relevant nonlinear forest wildfire size functions.Data from the Prague-East District of the Czech Republic was used for model derivation.Individual burned forest area was hypothesized as a function of water vapor pressure,air temperature and wind speed.Wind speed was added to enhance predictions of the size of forest wildfires,and further improvements to the utility of prediction methods were added to the regression equation.The results show that if the air temperature increases,it may contain less water and the fuel will become drier.The size of the burned area then increases.If the relative humidity in the air increases and the wind speed decreases,the size of the burned area is reduced.Our model suggests that changes in the climate factors caused by ongoing climate change could cause significant changes in the size of wildfire in forests. 展开更多
关键词 Climatic variables Burned forest area Climate change Multiple linear regression
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Water Repellency of Cellulosic Fibrous Mats Impregnated with Organic Solutions Based on Recycled Polystyrene
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作者 Dafni Foti Costas Passialis +1 位作者 Elias Voulgaridis Stergios Adamopoulos 《Journal of Renewable Materials》 SCIE EI 2021年第1期85-96,共12页
Recycled polystyrene in combination with paraffin wax,alkyd resin,and gum rosin were used as components in formulations to investigate their water repellency when applied to cellulosic filter paper substrates.Polystyr... Recycled polystyrene in combination with paraffin wax,alkyd resin,and gum rosin were used as components in formulations to investigate their water repellency when applied to cellulosic filter paper substrates.Polystyrene was used in concentration of 5,10,15 and 20%,alkyd resin and gum rosin of 5%each and paraffin wax of 0.5%.Totally,twenty four water repellent solutions were prepared.Water repellency was evaluated in terms of water absorption of the cellulosic fibrous mats.The relations between retention of solid substances of the formulations and grammage and water absorption of filter paper samples were also determined.The results showed that all the water repellent formulations exhibited a degree of water repellency.Water absorption decreased by increasing the polystyrene concentration in the solution and polystyrene retention by the impregnated filter paper samples.The incorporation of 0.5%paraffin wax improved the hydrophobicity of treated samples.The best of the three water repellent formulations including paraffin wax was found to be the“polystyrene+gum rosin+paraffin wax”solution followed by the“polystyrene+alkyd resin+paraffin wax”and“polystyrene+paraffin wax”solution.The inclusion of 5%gum rosin in polystyrene solutions compared to that of 0.5%paraffin wax was found more effective in almost all cases. 展开更多
关键词 Water repellents POLYSTYRENE gum rosin alkyd resin paraffin wax water absorption
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A basal area increment model for individual trees in mixed continuous cover forests in Iranian Caspian forests
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作者 Nishtman Hatami Peter Lohmander +1 位作者 Mohammad Hadi Moayeri Soleiman Mohammadi Limaei 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第1期99-106,共8页
The aim of this study was to develop and test a new basal area growth model in mixed species continuous cover forests in northern Iran.Weanalyzed 421 core samples from 6 main species in the forest area to develop our ... The aim of this study was to develop and test a new basal area growth model in mixed species continuous cover forests in northern Iran.Weanalyzed 421 core samples from 6 main species in the forest area to develop our growth model.In each plot,we measured variables such as total tree height(m),diameter at breast height(DBH)(cm)and basal area of larger trees as cumulative basal areas of trees(GCUM)ofDBH[5 cm.The empirical data were analyzed using regression analysis.There was a statistically significant nonlinear function between the annual basal area increment,as the dependent variable,and the basal area of the individual trees and competition as explanatory variables.Reference area from the largest trees,was circular plot with area of 0.1 ha.GCUM was estimated for trees of DBH>5 cm.Furthermore,we investigated the dependencies of diameter growth of different species on stand density at different levels of competition,and diameter development of individual trees through time.The results indicate that competition caused by larger neighborhood trees has a negative effect on growth.In addition,the maximum diameter increment is affected by competition level.Therefore,the maximum diameter increment of species occurs when the trees are about 35–40 cm in dense-forest(40 to 0 m^2 per ha)and when the trees are about 60 to 70 cm in very dense forest(60 to 0 m^2 per ha)which is more likely to Caspian natural forests with high level density due to uneven-aged composition of stands. 展开更多
关键词 Individual-tree model Iranian Caspian forests Continuous cover forestry Mixed stands Uneven-aged management
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