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Mapping and understanding degradation of alpine wetlands in the northern Maloti-Drakensberg, southern Africa

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Journal of Mountain Science 2024年第9期21卷 2956-2966页

作者： johan van TOL Department of Soil Crop and Climate SciencesUniversity of the Free StateBloemfontein 9300South Africa

The alpine terrestrials of the Maloti-Drakensberg in southern Africa play crucial roles in ecosystem functions and livelihoods,yet they face escalating degradation from various factors including overgrazing and climate *** study employs advanced Digital Soil Mapping(DSM)techniques coupled with remote sensing to map and assess wetland coverage and degradation in the northern *** model achieved high accuracies of 96%and 92%for training and validation data,respectively,with Kappa statistics of 0.91 and 0.83,marking a pioneering automated attempt at wetland mapping in this *** attributes such as terrain wetness index(TWI)and valley depth(VD)exhibit significant positive correlations with wetland coverage and erosion gully density,Channel Network Depth and slope were negative *** density analysis revealed terrain attributes as dominant factors driving degradation,highlighting the need to consider catchment-specific susceptibility to *** challenge traditional assumptions which mainly attribute wetland degradation to external forces such as livestock overgrazing,ice rate activity and climate *** sensitivity map produced could serve as a basis for Integrated Catchment Management(ICM)projects,facilitating tailored conservation *** research should expand on this work to include other highland areas,explore additional covariates,and categorize wetlands based on hydroperiod and sensitivity to *** comprehensive study underscores the potential of DSM and remote sensing in accurately assessing and managing wetland ecosystems,crucial for sustainable resource management in alpine regions.

关键词： Digital Soil Mapping Gully density Integrated catchment management Remote sensing Wetland degradation

Relating estimates of wood properties of birch to stem form, age and species

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Journal of Forestry Research 2024年第3期35卷 1-11页

作者： Grace Jones Maria Ulan Mateusz Liziniewicz johan Lindeberg Stergios Adamopoulos Teagasc Forestry Development Department Ashtown Research CentreDublin 15 D15DY05Ireland Research Institutes of Sweden(RISE) GoteborgSweden The Forest Research Institute of Sweden(Skogforsk) Ekebo 225026890SvalovSweden Department of Forestry and Wood Technology Linnaeus University35195VaxjoSweden Department of Forest Biomaterials and Technology Swedish University of Agricultural SciencesBox 700875007 UppsalaSweden

Birch has long suffered from a lack of active forest management,leading many researchers to use mate-rial without a detailed management *** collected from three birch(Betula pendula Roth,*** 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 *** sites were genetics trials established in the same *** 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 *** seemed likely that wood density was negatively related to ring width for both birch *** models had slight improvements if site and species were included,but only the youngest site with trees at age 15 had both birch *** 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.

关键词： Acoustic velocity Non-destructive testing Predictive models Regression analysis Wood density

Thermal Property Enhancement of a Novel Shape-Stabilized Sodium Acetate Trihydrate-Acetamide/Expanded Graphite-Based Composite Phase Change Material

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Journal of Thermal Science 2024年第4期33卷 1564-1576页

作者： AN Zhoujian hOU Wenjie DU Xiaoze hUANG Zhongzheng MOMBEKI PEA hamir johan ZhANG Dong LIU Xiaomin College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou730050China Key Laboratory of Multi-supply System with Solar Energy and Biomass of Gansu Province Lanzhou730050China Gansu Natural Energy Research Institute Lanzhou730046China

Phase change materials(PCMs)are a kind of highly efficient thermal storage materials which have a bright application prospect in many fields such as energy conservation in buildings,waste heat recovery,battery thermal management and so *** inorganic hydrated salt PCMs have received increasing attention from researchers due to their advantages of being inexpensive and ***,inorganic hydrated salt PCMs are still limited by the aspects of inappropriate phase change temperature,liquid phase leakage,large supercooling and severe phase separation in the application *** this work,sodium acetate trihydrate was selected as the basic inorganic PCM,and a novel shape-stabilized composite phase change material(CPCM)with good thermal properties was prepared by adding various functional *** first,the sodium acetate trihydrate-acetamide binary mixture was prepared and the melting point was adjusted using *** the binary mixture was incorporated into expanded graphite to synthesize a novel shape-stabilized *** thermophysical properties of the resultant shape-stabilized CPCM were systematically *** microscopic morphology and chemical structure of the obtained shape-stabilized CPCM were characterized and *** experiment results pointed out that acetamide could effectively lower the melting point of sodium acetate *** obtained shape-stabilized CPCM modified with additional 18%(mass fraction)acetamide and 12%(mass fraction)expanded graphite exhibited good shape stability and thermophysical characteristics:a low supercooling degree of 1.75℃and an appropriate melting temperature of 40.77℃were obtained;the latent heat of 151.64 kJ/kg and thermal conductivity of 1.411 W/(m·K)were also ***,after 50accelerated melting-freezing cycles,the obtained shape-stabilized CPCM represented good thermal reliability.

关键词： sodium acetate trihydrate melting point modification agent expanded graphite shape stability thermal conductivity enhancement

Exploring well-being disparities between urban and rural areas:A case study in the Stavropol Territory,Russia

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Regional Sustainability 2024年第1期5卷 80-92页

作者： Anastasia ChAPLITSKAYA Wim hEIJMAN johan van OPhEM Agricultural Economics and Rural Policy Group Wageningen University and ResearchWageningen6700 ABNetherlands Department of Foreign Languages Stavropol State Agrarian UniversityStavropol355017Russia Department of Economics Faculty of Economics and ManagementCzech University of Life SciencesPrague16500Czech Urban Economics Group Wageningen University and ResearchWageningen6700 ABNetherlands

Rural areas are crucial for a country’s sustainable *** strategies are needed to develop rural areas to improve the well-being of rural population and generate new job *** is especially important in countries where agricultural production accounts for a significant share of the gross product,such as *** this study,we identified the key indicators of satisfaction and differences between rural and urban citizens based on their social,economic,and environmental backgrounds,and determined whether there are well-being disparities between rural and urban areas in the Stavropol Territory,*** collected primary data through a survey based on the European Social Survey framework to investigate the potential differences between rural and urban *** computing the regional well-being index using principal component analysis,we found that there was no statistically significant difference in well-being between rural and urban *** of key indicators showed that rural residents felt psychologically more comfortable and safer,assessed their family relationships better,and adhered more to traditions and ***,urban residents showed better economic and social conditions(e.g.,infrastructures,medical care,education,and Internet access).The results of this study imply that we can better understand the local needs,advantages,and unique qualities,thereby gaining insight into the effectiveness of government ***-makers and local authorities can consider targeted interventions based on the findings of this study and strive to enhance the well-being of both urban and rural residents.

关键词： Well-being Sustainable development Rural areas Urban areas Principal component analysis(PCA) Russia

New indices to balanceα-diversity against tree size inequality

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Journal of Forestry Research 2024年第1期35卷 229-237页

作者： Li Zhang Brady K.Quinn Cang hui Meng Lian johan Gielis Jie Gao Peijian Shi College of Ecology and Environment Bamboo Research InstituteNanjing Forestry University159 Longpan RoadNanjing 210037People’s Republic of China Fisheries and Oceans Canada Andrews Biological Station125 Marine Science DriveSt.AndrewsNB E5B 0E4Canada Department of Mathematical Sciences Centre for Invasion BiologyStellenbosch UniversityMatieland 7602South Africa Mathematical and Physical Biosciences African Institute for Mathematical SciencesCape Town 7945South Africa Department of Biosciences Engineering University of AntwerpB-2020 AntwerpBelgium College of Life Science Xinjiang Normal University102 Xinyi RoadUrumqi 830054People’s Republic of China

The number and composition of species in a community can be quantified withα-diversity indices,including species richness(R),Simpson’s index(D),and the Shannon-Wiener index(h΄).In forest communities,there are large variations in tree size among species and individu-als of the same species,which result in differences in eco-logical processes and ecosystem ***,tree size inequality(TSI)has been largely neglected in studies using the available diversity *** TSI in the diameter at breast height(DBh)data for each of 99920 m×20 m forest census quadrats was quantified using the Gini index(GI),a measure of the inequality of size *** generalized performance equation was used to describe the rotated and right-shifted Lorenz curve of the cumulative proportion of DBh and the cumulative proportion of number of trees per *** also examined the relationships ofα-diversity indices with the GI using correlation *** generalized performance equation effectively described the rotated and right-shifted Lorenz curve of DBh distributions,with most root-mean-square errors(990 out of 999 quadrats)beingh of threeα-diversity indices(i.e.,R,D,and h’)and the ***,the total abundance of trees in each quadrat did not significantly influence the *** means that the TSI increased with increasing spe-cies ***,two new indices are proposed that can balanceα-diversity against the extent of TSI in the com-munity:(1−GI)×D,and(1−GI)×h’.These new indices were significantly correlated with the original D and h΄,and did not increase the extent of variation within each group of *** study presents a useful tool for quantifying both species diversity and the variation in tree sizes in forest communities,especially in the face of cumulative species loss under global climate change.

关键词： Diameter at breast height(DBh) Gini index Shannon-Wiener index Simpson’s index Quadrat Tree size

Editorial for Special Issue on Artificial Intelligence for Art

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Machine Intelligence Research 2024年第1期21卷 1-3页

作者： Luntian Mou Feng Gao Zijin Li Jiaying Liu hongxun Yao johan F.hoorn Beijing University of Technology China Peking University China Central Conservatory of Music China harbin Institute of Technology China The hong Kong Polytechnic University China

As an innovative engine for digital content generation,AI-generated content(AIGC)has drawn more and more attention from academic fields as well as *** in the area of art creation,AI has demonstrated its great potential and gained increasing *** are greatly impressed by AI painting,composing,writing,virtual hosting,fashion,and ***,AI is also becoming capable of understanding art,evaluating the aesthetic value of art,and protecting the copyright of art as *** has not only exhibited creativity to some extent,but also served as an enabling tool to discover the principles underneath creativity and imagination,which are traditional challenges for neuroscience,cognitive science,and *** all these promising features of AI for art,we still have to face the many challenges such as the explainability of generative models and the copyright issues of AI art works.

关键词： gained becoming spite

Expression changes of mi RNA-regulated genes associated with the formation of the leafy head in cabbage

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horticultural Plant Journal 2024年第4期10卷 1007-1019页

作者： Jorge Aleman-Baez Jose Fernando Acevedo-Zamora johan Bucher Chengcheng Cai Roeland E.Voorrips Guusje Bonnema Plant Breeding Wageningen University and ResearchWageningenThe Netherlands

The vegetative development of cabbage(Brassica oleracea ***)passes through seedling,rosette,folding and heading *** that form the rosette are large and mostly *** the following developmental stages,the plants produce leaves that curve inward to produce the leafy *** microRNAs and their target genes have been described participating in leaf development and leaf *** aim of this study is to investigate the role of miRNA-regulated genes in the transition from the rosette to the heading *** compared the mi RNA and gene abundances between emerging rosette and heading *** remove transcripts(miRNAs and genes)whose regulation was most likely associated with plant age rather than the change from rosette to heading stage,we utilized a non-heading collard green(*** ***)morphotype as *** resulted in 33 DEMs and 1998 DEGs with likely roles in the transition from rosette to heading stage in *** these 1998 DEGs,we found enriched GO terms related to DNA-binding transcription factor activity,transcription regulator activity,iron ion binding,and *** predicted the target genes of these 33 DEMs and focused on the subset that was differentially expressed(1998DEGs)between rosette and heading stage leaves to construct mi RNA-target gene interaction *** main finding is a role for miR396b-5p targeting two Arabidopsis thaliana orthologues of GROWTh REGULATING FACTORs 3(GRF3)and 4(GRF4)in pointed cabbage head formation.

关键词： Brassica oleracea var.capitata RNA sequencing miRNA-target gene network leafy head formation

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声子晶体中的三维量子霍尔效应

Science Bulletin 2024年第14期69卷 2149-2150页

作者：郑立洋 johan Christensen School of Science Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China IMDEA Materials Institute Getafe 28906Spain

At low temperatures,when a semiconductor hosts a two-dimensional electron gas(2DEG)and is subjected to a strong magnetic field,the hall resistance exhibits quantization to integer multiples of h/e2with remarkable precision(h is Planck’s constant and e is the elementary charge).The phenomenon,soon recognized as the quantum hall effect(QhE),emerged as a groundbreaking discovery in condensed matter physics[1,2],stimulating exploration into new research *** discovery paved the way for the investigation of topological states of matter,leading to unforeseen theoretical insights and practical applications.

关键词：量子霍尔效应 integer elementary

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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Agricultural Sciences 2024年第8期15卷 962-992页

作者： Mthintwa Tawanda hove hlamalani Ngwenya johan Van Niekerk Faculty of Agriculture and Natural Sciences Center of Sustainable Agriculture Extension and Rural Development University of the Free State Bloemfontein South Africa

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 to

关键词： Yield Gap Value Chain Development Soil health Varietal Replacement Rate Sustainability and Economic Mobility