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CEACAM1源性荧光多肽底物Site 84对MMP-2、-7、-9、-12酶活性检测的研究
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作者 万雯 叶雨佳 +5 位作者 杨晓娜 杨理宏 王华炜 董玲 陈丽星 孟照辉 《昆明医科大学学报》 2025年第2期9-16,共8页
目的探索CEACAM1源性多肽合成的荧光底物Site 84对MMP-2,-7,-9,-12酶活性的检测,并进一步探索荧光多肽底物Site 84在区分同属于MMPs明胶酶谱中MMP-2和MMP-9的应用。方法采用荧光酶学法观察荧光多肽底物Site 84对MMP-2,-7,-9,-12酶活性... 目的探索CEACAM1源性多肽合成的荧光底物Site 84对MMP-2,-7,-9,-12酶活性的检测,并进一步探索荧光多肽底物Site 84在区分同属于MMPs明胶酶谱中MMP-2和MMP-9的应用。方法采用荧光酶学法观察荧光多肽底物Site 84对MMP-2,-7,-9,-12酶活性的检测;进一步观察底物Site 84对明胶酶谱中MMP-2和MMP-9酶活性的敏感性和特异性;获得底物Site 84与MMP-2的酶促反应的动力学参数Km、Kcat。结果以Site 84为底物,获得MMP-12、-7、-2的酶活力曲线,但未获得MMP-9的酶活力曲线;此外,以Site 84为底物,可特异性检测明胶酶谱中MMP-2的酶活性,其可检测低浓度(0.6μM)MMP-2的酶活性,然而对高浓度(6μM)MMP-9未见明显酶促反应;最后,MMP-2和底物Site 84的酶促反应动力学参数:Km=315μM,Kcat/Km=2565/MS。结论以CEACAM1源性底物Site 84作为新型的荧光多肽底物,可获得MMP-12、-7、-2的酶活力曲线,且可特异性检测MMPs明胶酶谱中MMP-2的酶活性。 展开更多
关键词 site 84 荧光多肽底物 酶活性 明胶酶 CEACAM1源性
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Revisiting Active Sites for Nitrogen Reduction Reaction on 2D Materials Supported Metal Atoms: A Theoretical Investigation
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作者 Mingxin Qin Wenhua Zhang 《Chinese Journal of Chemical Physics》 2025年第3期311-322,I0025-I0036,I0109,共25页
Single atom catalysts supported by two-dimensional(2D)materials,including graphene,g-C_(3)N_(4),and graphdiyne,ex-hibit promising electrocatalytic nitrogen reduction reaction(NRR)activity.Nevertheless,sometimes theore... Single atom catalysts supported by two-dimensional(2D)materials,including graphene,g-C_(3)N_(4),and graphdiyne,ex-hibit promising electrocatalytic nitrogen reduction reaction(NRR)activity.Nevertheless,sometimes theoretical works failed to predict the high activity of NRR of single atom cat-alysts,especially for Fe,Co,Mn,Cu,Ru.In this work,based on DFT calculations,it is suggested that dual-atom sites on N doped graphene(M_(2)@N-graphene)rather than single-atom sites are more likely to be the active sites for NRR.Notably,Fe_(2)@N_(3),Co_(2)@N_(2),Mn_(2)@N_(2),Cu_(2)@N_(1),and Ru_(2)@N_(3)endow the best catalytic activity with corresponding limiting potentials of-0.26,-0.18,-0.17,-0.39,and-0.30 V,re-spectively.Furthermore,on g-C_(3)N_(4)and graphdiyne,triple-atom sites(TAS,M_(3))such as Ru_(3)(Co_(3))@g-C_(3)N_(4)and Ru_(3)(Rh_(3))@graphdiyne are expected to exhibit higher stability and NRR catalytic performance than single-atom sites(SAS)and dual-atom sites(DAS),with corresponding limiting potentials of-0.28,-0.48,-0.24,and-0.23 V.The calculated results with the corresponding experimental potentials indicate that the origin of superior NRR ac-tivity observed in experiments may be contributed by M_(2)or M_(3)on 2D materials.This study provides an in-depth investigation into real active NRR sites of metal atoms supported on 2D materials and contributes to the design of effective NRR catalysts. 展开更多
关键词 Single-atom catalysts Dual-atom sites Density functional theory Electrocat-alytic nitrogen reduction Active sites
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Functional macrocyclic arenes with active binding sites inside cavity for biomimetic molecular recognition
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作者 Xixian Sun Shengke Li +1 位作者 Ruibing Wang Leyong Wang 《Chinese Chemical Letters》 2025年第4期1-2,共2页
Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active... Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active sites inside the cavity of macrocyclic arenes to better mimic molecular recognition of bioreceptors and enzymes.The editorial aims to enlighten scientists in this field when they develop novel macrocycles for molecular recognition, supramolecular assembly, and applications. 展开更多
关键词 supramolecular assembly orthogonal interactions introducing active sites active binding sites macrocyclic arenes molecular recognition orthogonal interactions small molecules biomimetic molecular recognition
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A two-scale framework for mapping site productivity of Eucalyptus globulus Labill.plantations in northern Spain in the context of climate change and using spatially explicit environmental variables as predictors
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作者 Iyan Teijido-Murias Carlos A.Lopez-Sanchez +4 位作者 Pilar Garcia-Manteca Juan Daniel Garcia Villabrille Alberto Rojo-Alboreca Federico Ruiz Marcos Barrio-Anta 《Forest Ecosystems》 2025年第5期877-893,共17页
This research aimed to obtain accurate estimates of the productivity of eucalyptus plantations under different climate change scenarios without the need for additional fieldwork.Thus,we used tree growth data from 1,10... This research aimed to obtain accurate estimates of the productivity of eucalyptus plantations under different climate change scenarios without the need for additional fieldwork.Thus,we used tree growth data from 1,102research plots,existing spatially continuous environmental data,and the random forest(RF) algorithm to construct raster-based models.We constructed models to predict site index(SI) at landscape scale(250m·pixel^(-1)),which is useful for planning purposes and for analyzing the effect of climate change on productivity,and at forest plot scale(resolutions of 10,25,50,and 100 m-pixel^(-1)),which is essential for predicting plantation yields.All models explained~50% of site index variability,as is usual in this type of study.We found that the different spatial resolutions of predictor variables did not affect the amount of variability explained.This finding may be due to two opposing effects on the explained variability at finer scales:a positive effect,as finer scales enable capture of microscale landform variability through a high-resolution digital elevation model(DEM),and a negative effect due to the introduction of "noise" when downscaling the climatic and lithological information from coarser scales.Elevation and the climatic variables(mainly temperature) were the most important predictor variables:For every 100 m-increase in elevation,the productivity decreased by on average 0.3-0.9 m of site index(1-1.3 m^(3)·ha^(-1)·year^(-1) of maximum mean annual increment in volume) and for each degree-Celsiusincrease in annual mean temperature,productivity increased by about 2.2 m in site index(3 m^(3)·ha^(-1)·year^(-1)of maximum mean annual increment in volume).Due to the forecasted increase in temperatures under climate change,productivity is expected to increase significantly in Eucalyptus globulus plantations in northern Spain in the coming decades,by between 1.68% and 3.38% of the current average site index under the most pessimistic climate change scenario and between 1.79% and 2.48% of the current average site index for the moderate scenario.We conclude that currently available spatially continuous environmental data can be used to develop accurate raster data models for predicting site productivity for E.globulus without the need for fieldwork.The spatially explicit maps produced in the study provide support to forest planners,forest managers,private landowners and politicians,enabling well-founded decisions to be made regarding selection of the best sites for afforestation and providing accurate yield predictions for the plantations. 展开更多
关键词 Tasmanian blue gum site quality site index(SI) Spatial resolution Random forest(RF) Climate change
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Tuning Oxygen Vacancies by Construction of a SiO_(2)@TiO_(2) Core-Shell Composite Structure for Boosting Photocatalytic CO_(2) Reduction Towards CH_(4)
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作者 Jinshuo Li Chi Cao +5 位作者 Xiaoyu Zhang Huahua Dong Mengfei Wang Lin Zhang Zihao Xing Wensheng Yang 《Carbon Energy》 2025年第4期62-73,共12页
Controlled photocatalytic conversion of CO_(2) into premium fuel such as methane(CH4)offers a sustainable pathway towards a carbon energy cycle.However,the photocatalytic efficiency and selectivity are still unsatisfa... Controlled photocatalytic conversion of CO_(2) into premium fuel such as methane(CH4)offers a sustainable pathway towards a carbon energy cycle.However,the photocatalytic efficiency and selectivity are still unsatisfactory due to the limited availability of active sites on the current photocatalysts.To resolve this issue,the design of oxygen vacancies(OVs)in metal-oxide semiconductors is an effective option.Herein,in situ deposition of TiO_(2) onto SiO_(2) nanospheres to construct a SiO_(2)@TiO_(2) core-shell structure was performed to modulate the oxygen vacancy concentrations.Meanwhile,charge redistribution led to the formation of abundant OV-regulated Ti-Ti(Ti-OV-Ti)dual sites.It is revealed that Ti-OV-Ti dual sites served as the key active site for capturing the photogenerated electrons during light-driven CO_(2) reduction reaction(CO_(2)RR).Such electron-rich active sites enabled efficient CO_(2) adsorption and activation,thus lowering the energy barrier associated with the rate-determining step.More importantly,the formation of a highly stable*CHO intermediate at Ti-OV-Ti dual sites energetically favored the reaction pathway towards the production of CH4 rather than CO,thereby facilitating the selective product of CH_(4).As a result,SiO_(2)@TiO_(2)-50 with an optimized oxygen vacancy concentration of 9.0% showed a remarkable selectivity(90.32%)for CH_(4) production with a rate of 13.21μmol g^(-1) h^(-1),which is 17.38-fold higher than that of pristine TiO_(2).This study provides a new avenue for engineering superior photocatalysts through a rational methodology towards selective reduction of CO_(2). 展开更多
关键词 oxygen vacancy photocatalytic CO_(2)methanation SiO_(2)@TiO_(2)core-shell composite structure Ti-OV-Ti dual sites
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Selenate-based heterojunction with cobalt-nickel paired site for electrocatalytic oxidation of 5-hydroxymethylfurfural coupling water splitting to produce hydrogen 被引量:1
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作者 Zhengru Yang Jia Hui +4 位作者 Wangxi Fan Pengcheng Liu Chunyong Zhang Shuang Dong Zhou Yang 《Journal of Energy Chemistry》 2025年第2期156-162,I0005,共8页
It is very appealing that 5-hydroxymethylfurfural(HMF)is electrocatalytical oxidized as 2,5-furandicarboxylic acid(FDCA)linking to non-classical cathodic hydrogen(H_(2))production.However,the electrocatalysts for elec... It is very appealing that 5-hydroxymethylfurfural(HMF)is electrocatalytical oxidized as 2,5-furandicarboxylic acid(FDCA)linking to non-classical cathodic hydrogen(H_(2))production.However,the electrocatalysts for electrocatalytic HMF oxidative reaction(e-HMFOR)have been facing low Faradaic efficiency(FE)and high water splitting voltage.Herein,we propose a strategy of the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction by constructing a Co-Ni paired site,where the Co site is in charge of adsorbing for HMF while the electrons are transferred to the Ni site,thus giving the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction superior electrocata lytic performances for e-HMFOR and water splitting.By optimizing conditions,the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction has high conversion of 99.7%,high selectivity of 99.9%,and high FE of 98.4%at 1.3 V,as well as low cell voltage of 1.31 V at 10 mA cm^(-2)in 1 M KOH+0.1 M HMF.This study offers a potential insight for e-HMFOR to high value-added FDCA coupling water splitting to produce H_(2)in an economical manner. 展开更多
关键词 e-HMFOR FDCA Co-Ni paired site HETEROJUNCTION Hydrogen evolution
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Regulation Active Sites of Porous GaN Crystal Via Mn_(3)O_(4)Nanosheets for Advanced High Temperature Energy Storage 被引量:1
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作者 Songyang Lv Shouzhi Wang +7 位作者 Qirui Zhang Lin Xu Ge Tian Jiaoxian Yu Guodong Wang Lili Li Xiangang Xu Lei Zhang 《Energy & Environmental Materials》 2025年第3期112-121,共10页
Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and in... Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and inadequate energy densities are bottlenecks to its practical application.Herein,the self-supported GaN/Mn_(3)O_(4) integrated electrode is developed for both energy harvesting and storage under the high temperature environment.The experimental and theoretical calculations results reveal that such integrated structures with Mn-N heterointerface bring abundant active sites and reconstruct low-energy barrier channels for efficient charge transferring,reasonably optimizing the ions adsorption ability and strengthening the structural stability.Consequently,the assembled GaN based supercapacitors deliver the power density of 34.0 mW cm^(-2) with capacitance retention of 81.3%after 10000 cycles at 130℃.This work innovatively correlates the centimeter scale GaN single crystal with ideal theoretical capacity Mn_(3)O_(4) and provides an effective avenue for the follow-up energy storage applications of the wide bandgap semiconductor. 展开更多
关键词 active sites density functional theory gallium nitride crystal high temperature SUPERCAPACITORS
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Synergistic sites over the Zn_(x)ZrO catalyst for targeted cleavage of the C-H bonds of ethane in tandem with CO_(2)activation 被引量:1
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作者 Wenjun Qiang Duohua Liao +6 位作者 Maolin Wang Lingzhen Zeng Weiqi Li Xuedong Ma Liang Yang Shuang Li Ding Ma 《Chinese Journal of Catalysis》 2025年第3期272-284,共13页
The CO_(2)-assisted oxidative dehydrogenation of ethane(CO_(2)-ODHE)provides a promising way to produce ethylene and utilize CO_(2).Simultaneous upgrading of ethane into the high value-added chemical products and the ... The CO_(2)-assisted oxidative dehydrogenation of ethane(CO_(2)-ODHE)provides a promising way to produce ethylene and utilize CO_(2).Simultaneous upgrading of ethane into the high value-added chemical products and the reduction of greenhouse gas CO_(2)emissions could be achieved.However,the targeted breaking of the C-C/C-H bonds of ethane is still a challenge for the designed catalysts.In this paper,ZnO-doped ZrO_(2)bifunctional catalysts(Zn_(x)ZrO)with different Zn/Zr molar ratios were prepared by the deposition-precipitation method,and the functions of various sites for CO_(2)-ODHE reaction were revealed by in situ characterizations and ethane pulse experiment:the medium-strength acidic Zn-O-Zr sites are responsible for the purposefully cracking of ethane C-H bonds to ethylene,while the more oxygen vacancies(OV)created by the introduction of Zn^(2+)are responsible for the efficient activation C=O bonds of CO_(2),thus promoting the RWGS reaction.In addition,the Zn0.2ZrO catalyst demonstrated excellent catalytic performances,with C_(2)H_(6)conversion,C_(2)H_(4)yield,and CO_(2)conversion about 19.1%,10.5%,and 10.6%within 5 h,respectively(600℃,GHSV=3000 mL/(g·h)).Especially,the initial ethylene space-time yield of 355.5μmol/(min·g)was obtained under 6000 mL/(g·h);Finally,the tandem reaction mechanism of ethane dehydrogenation and RWGS was revealed. 展开更多
关键词 Zn-O-Zr site Oxygen vacancies CO_(2) Ethylene space-time yield Tandem reaction
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Standardized framework for assessing soil quality at antimony smelting site by considering microbial-induced resilience and heavy metal contamination 被引量:1
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作者 Shasha Jiang Xiaoyu Deng +6 位作者 Liyuan Ma Hongmei Wang Xingjie Wang Liang Feng Feng Zhu Shengguo Xue Arif Mohammad 《Journal of Environmental Sciences》 2025年第2期306-320,共15页
Antimony smelting activities damage the soil and vegetation surroundings while generating economic value.However,no standardizedmethods are available to diagnose the extent of soil degradation at antimony smelting sit... Antimony smelting activities damage the soil and vegetation surroundings while generating economic value.However,no standardizedmethods are available to diagnose the extent of soil degradation at antimony smelting sites.This study developed a standardized framework for assessing soil quality by consideringmicrobial-induced resilience and heavymetal contamination at Xikuangshan antimony smelting site.The soil resilience index(SRI)and soil contamination index(SCI)were calculated byMinimum Data Set and geo-accumulation model,respectively.After standardized by a multi-criteria quantitative procedure of modified Nemerow’s pollution index(NPI),the integrated assessment of soil quality index(SQI),which is the minimumof SRINPI and SCINPI,was achieved.The results showed that Sb and As were the prominent metal(loid)pollutants,and significant correlations between SQI and SRI indicated that the poor soil quality was mainly caused by the low level of soil resilience.The primary limiting factors of SRI were Fungi in high andmiddle contaminated areas,and Skermanella in low contaminated area,suggesting that the weak soil resilience was caused by low specific microbial abundances.Microbial regulation and phytoremediation are greatly required to improve the soil quality at antimony smelting sites from the perspectives of pollution control and resilience improvement.This study improves our understanding of ecological effects of antimony smelting sites and provides a theoretical basis for ecological restoration and sustainable development of mining areas. 展开更多
关键词 Antimony smelting site Soil resilience index(SRI) Soil contamination index(SCI) MICROORGANISMS Nemerow’s pollution index(NPI)
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Prediction of RNA m6A Methylation Sites in Multiple Tissues Based on Dual-branch Residual Network
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作者 GUO Xiao-Tian GAO Wei +2 位作者 CHEN Dan LI Hui-Min TAN Xue-Wen 《生物化学与生物物理进展》 北大核心 2025年第11期2900-2915,共16页
Objective N6-methyladenosine(m6A),the most prevalent epigenetic modification in eukaryotic RNA,plays a pivotal role in regulating cellular differentiation and developmental processes,with its dysregulation implicated ... Objective N6-methyladenosine(m6A),the most prevalent epigenetic modification in eukaryotic RNA,plays a pivotal role in regulating cellular differentiation and developmental processes,with its dysregulation implicated in diverse pathological conditions.Accurate prediction of m6A sites is critical for elucidating their regulatory mechanisms and informing drug development.However,traditional experimental methods are time-consuming and costly.Although various computational approaches have been proposed,challenges remain in feature learning,predictive accuracy,and generalization.Here,we present m6A-PSRA,a dual-branch residual-network-based predictor that fully exploits RNA sequence information to enhance prediction performance and model generalization.Methods m6A-PSRA adopts a parallel dual-branch network architecture to comprehensively extract RNA sequence features via two independent pathways.The first branch applies one-hot encoding to transform the RNA sequence into a numerical matrix while strictly preserving positional information and sequence continuity.This ensures that the biological context conveyed by nucleotide order is retained.A bidirectional long short-term memory network(BiLSTM)then processes the encoded matrix,capturing both forward and backward dependencies between bases to resolve contextual correlations.The second branch employs a k-mer tokenization strategy(k=3),decomposing the sequence into overlapping 3-mer subsequences to capture local sequence patterns.A pre-trained Doc2vec model maps these subsequences into fixeddimensional vectors,reducing feature dimensionality while extracting latent global semantic information via context learning.Both branches integrate residual networks(ResNet)and a self-attention mechanism:ResNet mitigates vanishing gradients through skip connections,preserving feature integrity,while self-attention adaptively assigns weights to focus on sequence regions most relevant to methylation prediction.This synergy enhances both feature learning and generalization capability.Results Across 11 tissues from humans,mice,and rats,m6A-PSRA consistently outperformed existing methods in accuracy(ACC)and area under the curve(AUC),achieving>90%ACC and>95%AUC in every tissue tested,indicating strong cross-species and cross-tissue adaptability.Validation on independent datasets—including three human cell lines(MOLM1,HEK293,A549)and a long-sequence dataset(m6A_IND,1001 nt)—confirmed stable performance across varied biological contexts and sequence lengths.Ablation studies demonstrated that the dual-branch architecture,residual network,and self-attention mechanism each contribute critically to performance,with their combination reducing interference between pathways.Motif analysis revealed an enrichment of m6A sites in guanine(G)and cytosine(C),consistent with known regulatory patterns,supporting the model’s biological plausibility.Conclusion m6A-PSRA effectively captures RNA sequence features,achieving high prediction accuracy and robust generalization across tissues and species,providing an efficient computational tool for m6A methylation site prediction. 展开更多
关键词 N6-methyladenosine site Doc2vec BiLSTM dual-branch residual network self-attention
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Active sites and impact of preparation pH on the Cu/ZnO/ZrO_(2) catalysts for methanol production via CO_(2) hydrogenation
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作者 MENG Xinyue SUN Shangcong +1 位作者 CAO Shuo PENG Bo 《燃料化学学报(中英文)》 北大核心 2025年第11期1569-1582,共14页
Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active... Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active centers influencing the rate of both methanol and CO formation.The particle size and the interaction between Cu and the support materials are influenced by the coprecipitation conditions,let alone that the mechanistic divergence remains unclear.In this work,a series of Cu/ZnO/ZrO_(2) catalysts were prepared via co-precipitation at different pH value and systematically characterized.The structure has been correlated with kinetic results to establish the structure-performance relationship.Kinetic analysis demonstrates that methanol synthesis follows a single-site Langmuir-Hinshelwood(L-H)mechanism,i.e.,Cu serves as the active site where CO_(2) and H_(2) competitively adsorb and react to form methanol.In contrast,CO formation proceeds via a dual-site L-H mechanism,where CO_(2) adsorbs onto ZnO and H_(2) onto Cu,with the reaction occurring at the Cu/ZnO interface.Therefore,for the direct formation of methanol,solely reducing the particle size of Cu would not be beneficial. 展开更多
关键词 CO_(2)hydrogenation methanol synthesis active sites KINETICS
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Assessment of Floristic Diversity at Two Protected Sites on the Outskirts of Sena Oura National Park, Chad
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作者 Robert Tchingonta Maxime Banoin +1 位作者 Koussou Mian-Oudanang Sougnabe Pabame 《Agricultural Sciences》 2025年第1期178-192,共15页
Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highli... Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highlight the floristic diversity of the herbaceous and woody vegetation on these sites in the offing to know the ability of charge into UBT that most support the park peripheral. It took place on two experimental sites on a natural course in two villages: Wazetelan and Massang. The approach used for the study was a survey using the systematic sampling method and a 30 m × 30 m plot. The survey consisted in listing all the taxa in a floristically homogeneous plot, each assigned the Braun-Blanquet dominance abundance coefficient. These surveys revealed a floristic richness of 73 species, 58 genera, including 46 herbaceous and 26 woody species. The Shannon result gives H1' = 0.12 bit for herbaceous species and H2' = 0.44 bit for woody species, meaning that the herbaceous and woody populations of all the surveys have a very low species diversity, as H' < 3 according to the Shannon index assessment threshold. Herbaceous species are divided into 13 families and 33 genera. The most represented families are Fabaceae (27.3%) and Poaceae (21.9%). Most of the other families (1.3%) have only one species, if any. Herbaceous species are divided into 33 genera grouped into 13 families. The most represented families are Fabaces (16 species), 34%, and Poaceae (12 species), 26%. The 26 woody species, most of which come from itinerant surveys, are distributed across 24 genera and 12 families, the most important of which is Fabaceae with 09 species (34.6%). This floristic assessment, in terms of quantity and quality, has enabled us to estimate the carrying capacity of the two pastoral enclaves in Dari and Goumadji cantons, and to guide the government’s actions with regard to rangeland management. 展开更多
关键词 Floristic Diversity Protected sites PERIPHERY Area Producty CHAD
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Probabilistic Site Investigation Optimization of Gassy Soils Based on Conditional Random Field and Monte Carlo Simulation
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作者 Shaolin Ding 《World Journal of Engineering and Technology》 2025年第1期1-11,共11页
Gassy soils are distributed in relatively shallow layers the Quaternary deposit in Hangzhou Bay area. The shallow gassy soils significantly affect the construction of underground projects. Proper characterization of s... Gassy soils are distributed in relatively shallow layers the Quaternary deposit in Hangzhou Bay area. The shallow gassy soils significantly affect the construction of underground projects. Proper characterization of spatial distribution of shallow gassy soils is indispensable prior to construction of underground projects in the area. Due to the costly conditions required in the site investigation for gassy soils, only a limited number of gas pressure data can be obtained in engineering practice, which leads to the uncertainty in characterizing spatial distribution of gassy soils. Determining the number of boreholes for investigating gassy soils and their corresponding locations is pivotal to reducing construction risk induced by gassy soils. However, this primarily relies on the engineering experience in the current site investigation practice. This study develops a probabilistic site investigation optimization method for planning investigation schemes (including the number and locations of boreholes) of gassy soils based on the conditional random field and Monte Carlo simulation. The proposed method aims to provide an optimal investigation scheme before the site investigation based on prior knowledge. Finally, the proposed approach is illustrated using a case study. 展开更多
关键词 Gassy Soils site Investigation UNCERTAINTY Conditional Random Field Monte Carlo Simulation
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Analysis of Two Irrigation Water Pumping Systems on the Taddis Valley Site: Solar Kit and Motor Pump Unit (GMP) in Tahoua (Niger)
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作者 Yerima Bako Djibo Aboubacar Guero Yadji Bori Haoua 《World Journal of Engineering and Technology》 2025年第1期39-48,共10页
The study was carried out in the Tahoua region at the market gardening sites of the Taddis 1 and 2 valley. Small-scale pumping irrigation is one of the most interesting uses of solar energy. The objective of this stud... The study was carried out in the Tahoua region at the market gardening sites of the Taddis 1 and 2 valley. Small-scale pumping irrigation is one of the most interesting uses of solar energy. The objective of this study is to carry out a comparative analysis of two dewatering pumping systems (Solar Kit and GMP) for water mobilization on a certain number of criteria such as sustainable use, economic aspect and performance. To achieve this, the adapted methodology consisted first of all in the development of a data collection tool in the field. Then flow measurements, estimation of fuel consumption, pressure height, etc., were carried out. Thus, the data collection involved a sample of 120 irrigators who had to use the two (2) types of pumping systems. The collected data were analyzed and processed with appropriate software. The results of the study show that the two pumping systems studied have strengths and constraints. Thus, the solar pumping system has a significant investment cost, very low maintenance and a low operating cost. On the other hand, the system with a generator has a relatively low investment cost (25 to 30 times less than solar), but a relatively high operating, upkeep and maintenance cost. He adds that these assets and constraints must be taken into consideration when an investment is made. This study shows that 74% of producers use GMP compared to 26% who use the Solar Kit. But in practice, the Solar Kit is more reliable for producers from the point of view of planted area, environmental management and investment costs, supply of fuel and lubricant. These results indicate better performance of the solar pumping system compared to GMP at the study sites. 展开更多
关键词 Market Gardening sites Pumping Systems Solar Kit GMP Taddis and Tahoua Valley
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Prevalence and Risk Factors for Surgical Site Infection Following Cesarean Section in a Tertiary Care Hospital
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作者 Nafisa Ahamed Md. Alimur Reza +3 位作者 Kakali Saha Rabeya Khanom Shovana Talukder Arifa Akram 《Open Journal of Obstetrics and Gynecology》 2025年第2期261-271,共11页
Background: Cesarean sections have become increasingly prevalent in both developed and developing nations. Nevertheless, postoperative complications, including surgical site infections (SSIs), remain a substantial con... Background: Cesarean sections have become increasingly prevalent in both developed and developing nations. Nevertheless, postoperative complications, including surgical site infections (SSIs), remain a substantial concern that contributes to heightened morbidity and mortality. This study is designed to evaluate the frequency and key determining factors associated with surgical site infections following cesarean section procedures in a tertiary care hospital in Bangladesh. Materials and Methods: This observational cross-sectional study, conducted at the Gynecology Department of Dhaka Medical College Hospital, involved 100 patients aged 15 - 45 who had cesarean deliveries. Data was collected during hospitalization and post-discharge and analyzed to determine the prevalence and relationship between socio-demographic characteristics and surgical site infection. Results: Among the study participants, 14% developed surgical site infections following cesarean operations. More than half of these patients were under the age of 25, with a mean age of 24.45 ± 4.44 years. Surgical site infections were more prevalent in individuals over 30 years old (P-value Conclusion: Post-cesarean surgical site infections are notably prevalent among the participants in this study. Several risk factors have been identified, including age, body mass index (BMI), socioeconomic status, anemia, preterm delivery, personal hygiene practices, regular menstrual cycles, and adherence to antenatal check-ups. The implementation of an effective awareness program, coupled with updated antibiotic protocols, is crucial for significantly reducing the incidence of these infections. 展开更多
关键词 Surgical site Infection (SSI) Cesarean Section Risk Factors
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Integrated single-cell transcriptomic map of pig kidney cells across various periods and anatomical sites
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作者 Tian-Xiong Yao Na Li Lu-Sheng Huang 《Zoological Research》 2025年第2期469-482,共14页
The kidney is essential for maintaining fluid,electrolyte,and metabolite homeostasis,and for regulating blood pressure.The pig serves as a valuable biomedical model for human renal physiology,offering insights across ... The kidney is essential for maintaining fluid,electrolyte,and metabolite homeostasis,and for regulating blood pressure.The pig serves as a valuable biomedical model for human renal physiology,offering insights across different physiological states.In this study,single-cell RNA sequencing was used to profile 138469 cells from 12 pig kidney samples collected during the embryonic(E),fattening(F),and pregnancy(P)periods,identifying 29 cell types.Proximal tubule(PT)cells exhibited elevated expression of metabolism-related transcription factors(TFs),including GPD1,ACAA1,and AGMAT,with validation across multiple individuals,periods,and species.Fluorescence homologous double-labeling of paraffin sections further confirmed the expression of ACAA1 and AGMAT in PT cells.Comparative analysis of pig and human kidneys revealed a high degree of similarity among corresponding cell types.Analysis of cell-type heterogeneity highlighted the diversity of thick ascending limb(TAL)cells,identifying a TAL subpopulation related to immune function.Additionally,the functional heterogeneity of kidney-resident macrophages(KRM)was explored across different anatomical sites.In the renal medulla,KRM were implicated in phagocytosis and leukocyte activation,whereas in the renal pelvis,they functioned as ligands,recruiting neutrophils with bactericidal activity to the renal pelvis to combat urinary tract infections. 展开更多
关键词 PIG Kidney Single-cell RNA sequencing PERIODS Anatomical sites
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Nurses’levels of knowledge and practice regarding preoperative hair removal and prevention of surgical site infection
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作者 Hatice Hilal Cangi Akcan Senay Karadag Arli 《Frontiers of Nursing》 2025年第3期355-363,共9页
Objective:To evaluate nurses’levels of knowledge and practice regarding preoperative hair removal and prevention of surgical site infection(SSI).Methods:The descriptive and cross-sectional research was conducted betw... Objective:To evaluate nurses’levels of knowledge and practice regarding preoperative hair removal and prevention of surgical site infection(SSI).Methods:The descriptive and cross-sectional research was conducted between February 2023 and May 2023 in a public hospital in northern Turkey with 123 nurses who agreed to participate in the study.Results:The results showed that 64.2%of the nurses thought that preoperative hair removal should be done by shaving with a razor,74%thought that hair removal should be performed the night before the operation,and 70.7%thought that the patient/patient’s relative should perform preoperative hair removal.Conclusions:This study found that nurses’levels of knowledge and practice regarding preoperative hair removal and prevention of SSI were not at the desired level.Following current resources and improving their levels of knowledge and practices are considered to be important for nurses. 展开更多
关键词 hair removal NURSE PREOPERATIVE skin preparation surgical site infection
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Container size and site quality affect survival and early growth performance of New Zealand native tree species
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作者 David Pessanha Siqueira Craig Ford +3 位作者 Alexander Lloyd Donald White Guillermo Salvatierra Heidi Dungey 《Journal of Forestry Research》 2025年第4期149-157,共9页
As part of the global effort to mitigate climate change effects, New Zealand’s Climate Change Commission has recommended the establishment of 300,000 ha of native trees across the country by 2035. To achieve this goa... As part of the global effort to mitigate climate change effects, New Zealand’s Climate Change Commission has recommended the establishment of 300,000 ha of native trees across the country by 2035. To achieve this goal, significant improvement in seedling production and field establishment is needed. Across New Zealand, there is a trade-off between seedling size and early seedling establishment success;plants grown in large pots are more resistant to weeds, pests and frost;however, they are more expensive and take longer to grow. We tested this trade-off between cost and establishment success by raising seedlings of twelve key native species in three container grade sizes: small, large, and revegetation grade, and tracking their success across five sites around Rotorua, in the Central North Island of New Zealand. After two-year post-planting, we found that high-quality sites and larger container systems tended to promote higher survival and faster early growth (plant height and root collar diameter). Some species, such as Kunzea ericoides and Leptospermum scoparium, survived and grew well (> 75%) even when raised in small container sizes. Other species such as Sophora microphylla had very low survival (< 25%) even when raised in revegetation container grade sizes. If the quality of the planting site is high, the container size seems to be less important for most species. Other species such as Aristotelia serrata, Cordyline australis, Plagianthus regius and Podocarpus totara appear to depend more on site quality. In conclusion, nursery container systems for raising New Zealand native plants should be chosen based on the biology of the species, nursery management practices, quality of the planting site, and a balance between cost and benefit for each situation. 展开更多
关键词 Seedling production Containerised seedlings AFFORESTATION Degraded areas site quality
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RLsite:Integrating 3D-CNN and BiLSTM for RNA-ligand binding site prediction
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作者 Yan Zou Lang Yang +1 位作者 Yanhui Liu Yuyu Feng 《Chinese Physics B》 2025年第8期100-113,共14页
Accurate identification of RNA-ligand binding sites is essential for elucidating RNA function and advancing structurebased drug discovery.Here,we present RLsite,a novel deep learning framework that integrates energy-,... Accurate identification of RNA-ligand binding sites is essential for elucidating RNA function and advancing structurebased drug discovery.Here,we present RLsite,a novel deep learning framework that integrates energy-,structure-and sequence-based features to predict nucleotide-level binding sites with high accuracy.RLsite leverages energy-based threedimensional representations,obtained from atomic probe interactions using a pre-trained ITScore-NL potential,and models their contextual features through a 3D convolutional neural network(3D-CNN)augmented with self-attention.In parallel,structure-based features,including network properties,Laplacian norm,and solvent-accessible surface area,together with sequence-based evolutionary constraint scores,are mapped along the RNA sequence and used as sequential descriptors.These descriptors are modeled using a bidirectional long short-term memory(BiLSTM)network enhanced with multihead self-attention.By effectively fusing these complementary modalities,RLsite achieves robust and precise binding site prediction.Extensive evaluations across four diverse RNA-ligand benchmark datasets demonstrate that RLsite consistently outperforms state-of-the-art methods in terms of precision,recall,Matthews correlation coefficient(MCC),area under the curve(AUC),and overall robustness.Notably,on a particularly challenging test set composed of RNA structures containing junctions,RLsite surpasses the second-best method by 7.3%in precision,3.4%in recall,7.5%in MCC,and 10.8%in AUC,highlighting its potential as a powerful tool for RNA-targeted molecular design. 展开更多
关键词 RNA-ligand binding sites prediction deep learning self-attention
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Proximity electronic effect of adjacent Ni Site enhances compatibility of hydrogenation and deoxygenation over Cu Site to boost nitrate electroreduction to ammonia
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作者 Xue-Feng Cheng Qing Liu +5 位作者 Qi-Meng Sun Huilong Dong Dong-Yun Chen Ying Zheng Qing-Feng Xu Jian-Mei Lu 《Chinese Journal of Catalysis》 2025年第3期285-298,共14页
Electrocatalytic conversion of nitrate to ammonia(NITRR)can simultaneously achieve the removal of nitrate and the synthesis of value-added ammonia,a promising candidate to replace Haber-Bosch process with low carbon d... Electrocatalytic conversion of nitrate to ammonia(NITRR)can simultaneously achieve the removal of nitrate and the synthesis of value-added ammonia,a promising candidate to replace Haber-Bosch process with low carbon dioxide emissions.However,high hydrogenation energy barrier for*NO intermediates and insufficient supply of active hydrogen cause slow hydrogenation process,and further result in low efficiency of nitrate conversion and ammonia synthesis.Herein,a series of tandem catalysts,one-dimensional coordination polymers(1D CCPs)with dual sites are synthesized and obtained 190.4 mg h^(-1)mgcat^(-1)ammonia production rate with Faradaic efficiency of 97.16%,outperforming to the most of recent reported catalysts.The catalytic performances are well-maintained even after a long-term stability test of 1200 h,laying the foundation for practical applications.Density functional theory results reveal that the stationary adsorbed*NO on Ni site induced proximity electronic effect could reduce the energy barrier for hydrogenation of*NO intermediates over Cu site.In addition,the Ni site in the dual sites 1D CCPs is conducive to generating active hydrogen,providing rich proton source to boost the hydrogenation of*NO,and further enhancing the compatibility of deoxygenation and hydrogenation process.Our work paves a new insight into the mechanism of NITRR process and will inspire more research interests in exploring the proximity electronic effect in catalytic process. 展开更多
关键词 ELECTROCATALYSIS Ammonia synthesis Nitrate reduction Proximity electronic effect Dual sites
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