期刊文献+
共找到374篇文章
< 1 2 19 >
每页显示 20 50 100
Moving away from home:Early life movements and space use in juvenile Montagu's Harriers(Circus pygargus)from central Italy
1
作者 Giampiero Sammuri Guido Alari Esposito +4 位作者 Giuseppe Anselmi Francesco Pezzo Vincenzo Rizzo Pinna Andrea Sforzi Flavio Monti 《Avian Research》 2025年第2期251-263,共13页
Assessing individual differences and variability in animal movement patterns is essential to improve our understanding of the evolution and ontogeny of migratory strategies.In long-distance migratory species,fledged j... Assessing individual differences and variability in animal movement patterns is essential to improve our understanding of the evolution and ontogeny of migratory strategies.In long-distance migratory species,fledged juveniles often rely on an extremely restricted time span to learn the essential skills for survival and to prepare for migration,possibly the most risky phase of their lives.Collecting detailed information on the dynamics of the movements during the crucial pre-migratory phase is hence essential to understand the solutions developed by migratory species in different environmental contexts.Here,we used high-resolution GPS/GSM transmitters to collect information on the movement ecology of seven juvenile Montagu's Harriers(Circus pygargus)born in central Italy,investigating their early life stages,namely the post-fledging dependence period(PFDP)and the pre-migratory phase(PMP),until autumn migration.After fledging,individuals showed high variability(both in space and time)in home range size,daily distances covered(6.88±11.44 km/day),distance from the nest(1.45±2.8 km)and PFDP length(23.3±5.3 days).Residence time at the natal site significantly decreased,while time interval between revists in the natal area significantly increased,as the PFDP progressed.During the PMP,explored areas and distance from the nest(max value up to 320.8 km)varied among individuals,despite daily distances covered(27±40 km/day)and time allocation between traveling(60.7%)and foraging(39.3%)were similar across individuals.The PMP lasted 38±14 days.Land cover composition of foraging locations was mostly represented by agricultural lands(~78.2%),though habitat use differed among individuals.More than 76%of such locations were outside protected areas.This individual-based tracking study represents a novel approach that improves previous knowledge based on field studies on the early life stages of the Montagu's Harrier.High inter-individual variability in movement patterns,broad-range exploratory movements and foraging locations outside the protected area network make the application of standard conservation measures difficult,raising concerns about the long-term preservation of this vulnerable migratory species in Italy. 展开更多
关键词 Dispersal Habitat use Migration Post-fledging dependence period Protected areas RAPTOR
在线阅读 下载PDF
GGE analysis and stability of traits in tomato cultivars grown under organic farming conditions: A two-year study
2
作者 Pasquale Tripodi Salvador Soler +7 位作者 Gabriele Campanelli María RFigàs Cristina Casanova Elena Soler Sara Sestili Aldo Bertone Teodoro Cardi Jaime Prohens 《Horticultural Plant Journal》 2025年第2期721-736,共16页
The increasing conversion of agricultural land to organic farming requires the development of specifically adapted cultivars.So far,in tomato there is lack of research for selection of germplasm suitable for sustainab... The increasing conversion of agricultural land to organic farming requires the development of specifically adapted cultivars.So far,in tomato there is lack of research for selection of germplasm suitable for sustainable agroecosystems.In this study,we investigated the genotypic and environmental factors affecting the variation of plant,fruits,and root traits in 39 tomato genotypes grown under organic farming conditions.Four independent experiments were conducted in Italy and Spain across two consecutive seasons in 2019 and 2020.For all traits,the factorial linear regression model to estimate the main effects of genotype(G),location(L),year of cultivation(Y)and their interactions,revealed highly significant(P<0.001)variations,with the G factor being largely predominant for most traits.The implementation of the“which-won-where”,“mean performance versus stability”and“discriminative vs representativeness”patterns in the GGE(Genotype plus Genotype by Environment interaction)analysis,allowed the identification of superior cultivars with high stability across the testing environments.Genomic characterization with 30890 high quality SNPs from dd RADseq genotyping analysis,revealed that a specific cluster of cherry tomato accessions were low performing in terms of yield and fruit weight,on the contrary,showed a high content of soluble solids,which in agreement with GGE analysis.Results of this study provide a framework for the potential use of this locally adapted tomato germplasm to address the needs of more sustainable agriculture. 展开更多
关键词 Genotype by environment TOMATO Organic farming Field trials BREEDING
在线阅读 下载PDF
Microstructural Evolution of Rapidly Solidified Ni-Cu Alloys
3
作者 QU Shuwei LI Zejun +4 位作者 WANG Hongfu TIAN Xiaoguang QIAN Zhike LI Ruiqin YAO Wei 《Journal of Wuhan University of Technology(Materials Science)》 2025年第6期1759-1765,共7页
This study systematically investigated the microstructural evolution of binary Ni-Cu alloys(Cu55Ni45,Cu60Ni40,and Ni65Cu35)under deep undercooling conditions.The controlled rapid solidification experiments combined wi... This study systematically investigated the microstructural evolution of binary Ni-Cu alloys(Cu55Ni45,Cu60Ni40,and Ni65Cu35)under deep undercooling conditions.The controlled rapid solidification experiments combined with optical microscopy and electron backscatter diffraction(EBSD)analysis demonstrate that increasing undercooling(ΔT)can induce a consistent sequence of microstructural transitions:coarse dendrites,fine equiaxed grains(first refinement),oriented fine dendrites,and fine equiaxed grains(second refinement).Two distinct grain refinement events are identified,with critical undercooling thresholds(ΔT)dependent on composition:increasing Cu content increases the critical undercoolingΔT*required for the second refinement(Cu55Ni45:227 K;Cu60Ni40:217 K;Ni65Cu35:200 K).The BCT(Bridgman Crystal Growth)model quantitatively elucidates this behavior,revealing a shift from solute-diffusion-dominated growth at low undercooling to thermally dominated diffusion at high undercooling(ΔT).Crucially,refined grains at high undercooling exhibit smaller sizes(10μm)and higher uniformity than those at low undercooling(20μm).These findings provide fundamental insights into non-equilibrium solidification mechanisms and establish a foundation for designing high-performance Ni-Cu alloys via deep undercooling processing. 展开更多
关键词 deep undercooling Ni-Cu alloys microstructural evolution grain refinement BCT model rapid solidification
原文传递
Integrating Academic Research Methodologies like Participatory Action Research(PAR)into Design Thinking:A Framework for Group Housing Design
4
作者 Tadiboina Samantha Kumar Ramesh Srikonda 《Journal of World Architecture》 2025年第2期117-133,共17页
The integration of academic research methodologies into design thinking processes presents a transformative approach to addressing complex challenges in group housing,fostering inclusive,sustainable,and user-centered ... The integration of academic research methodologies into design thinking processes presents a transformative approach to addressing complex challenges in group housing,fostering inclusive,sustainable,and user-centered solutions.This research explores how methodologies such as Participatory Action Research,post-occupancy evaluations,and Research through Design can be systematically embedded within design thinking to bridge the gap between academic rigor and empathy-driven,iterative design practices.By synthesizing these paradigms,the study proposes a framework for group housing design that prioritizes co-design processes,empathy-based data collection,and participatory evaluation,while emphasizing adaptability through sociocultural insights and user feedback.Case studies analysis demonstrate the effectiveness of flexible,community-driven design,while emerging technologies like IoT-enabled cohousing signal new opportunities for innovation.Challenges,including scalability,long-term validation,and reconciling user autonomy with professional expertise,are critically analyzed.Ultimately,this research advances a hybrid methodology to redefine the conceptualization,implementation,and assessment of group housing,offering actionable pathways to achieve affordable,inclusive,and context-sensitive housing solutions. 展开更多
关键词 Design thinking Academic research methodologies Group housing Participatory Action Research(PAR) Co-Design Sustainable housing User-centered design
在线阅读 下载PDF
Automated Brain Tumor Classification from Magnetic Resonance Images Using Fine-Tuned Efficient Net-B6 with Bayesian Optimization Approach
5
作者 Sarfaraz Abdul Sattar Natha Mohammad Siraj +2 位作者 Majid Altamimi Adamali Shah Maqsood Mahmud 《Computer Modeling in Engineering & Sciences》 2025年第12期4179-4201,共23页
A brain tumor is a disease in which abnormal cells form a tumor in the brain.They are rare and can take many forms,making them difficult to treat,and the survival rate of affected patients is low.Magnetic resonance im... A brain tumor is a disease in which abnormal cells form a tumor in the brain.They are rare and can take many forms,making them difficult to treat,and the survival rate of affected patients is low.Magnetic resonance imaging(MRI)is a crucial tool for diagnosing and localizing brain tumors.However,themanual interpretation of MRI images is tedious and prone to error.As artificial intelligence advances rapidly,DL techniques are increasingly used in medical imaging to accurately detect and diagnose brain tumors.In this study,we introduce a deep convolutional neural network(DCNN)framework for brain tumor classification that uses EfficientNet-B6 as the backbone architecture and adds additional layers.The model achieved an accuracy of 99.10%on the public Brain Tumor MRI datasets,and we performed an ablation study to determine the optimal batch size,optimizer,loss function,and learning rate to maximize the accuracy and robustness of the model,followed by K-Fold cross-validation and testing the model on an independent dataset,and tuning Hyperparameters with Bayesian Optimization to further enhance the performance.When comparing our model to other deep learning(DL)models such as VGG19,MobileNetv2,ResNet50,InceptionV3,and DenseNet201,aswell as variants of the EfficientNetmodel(B1–B7),the results showthat our proposedmodel outperforms all othermodels.Our investigational results demonstrate superiority in terms of precision,recall/sensitivity,accuracy,specificity,and F1-score.Such innovations can potentially enhance clinical decision-making and patient treatment in neurooncological settings. 展开更多
关键词 Brain tumor classification convolutional neural network magnetic resonance imaging deep learning Bayesian optimization
在线阅读 下载PDF
Evolutionary adaptations in the limb morphology of tropidurid lizards in response to sandy environments
6
作者 María J.Tulli Ken S.Toyama 《Current Zoology》 2025年第5期581-592,共12页
Different habitat types exert particular challenges to ecological performance,ultimately having a strong influence on the evolution of morphology.Although it is well known that external morphology can evolve under the... Different habitat types exert particular challenges to ecological performance,ultimately having a strong influence on the evolution of morphology.Although it is well known that external morphology can evolve under the selective pressure of habitat structure,the evolutionary response of internal morphological traits remains vastly unexplored.Here,we test for morphological divergence between arenicolous and nonarenicolous species in a clade of tropidurid lizards,considering external morphological proportions and limb muscle dimensions.We found that arenicolous species seem to have evolved internal and external morphological adaptations that separate them from other habitat specialists.Moreover,comparative analyses suggested that the traits that differed the most between arenicolous and nonarenicolous lizards might have evolved divergently towards different optima.Additionally,the axis of higher morphological divergence between arenicolous and nonarenicolous species represented an important proportion of the morphological diversity within our sample,indicating that the hypothetical adaptive divergence of internal and external traits has contributed significantly to phenotypic diversity.Our results show that evolutionary associations between morphology and habitat use can be detected on both external body proportions and muscle morphology.Moreover,they highlight the emergent importance of internal anatomical traits in ecomorphological studies,especially when such traits are directly involved in determining functional performance. 展开更多
关键词 body shape ECOMORPHOLOGY muscles sand substrates Tropiduridae
原文传递
Geophysical data denoising using dictionary learning method with Ramanujan sums for oil and minerals exploration
7
作者 Lakshmi Kuruguntla Mamatha Bandaru +3 位作者 Dokku Tejaswi Anup Kumar Mandpura Sravan Kumar Sikhakoli Vineela Chandra Dodda 《Artificial Intelligence in Geosciences》 2025年第2期374-383,共10页
Denoising is an important preprocessing step in seismic exploration that improves the signal-to-noise ratio(SNR)and helps identify oil and minerals.Dictionary learning(DL)is a promising method for noise attenuation.Th... Denoising is an important preprocessing step in seismic exploration that improves the signal-to-noise ratio(SNR)and helps identify oil and minerals.Dictionary learning(DL)is a promising method for noise attenuation.The DL extracts sparse features from noisy seismic data using over-complete dictionaries and performs denoising based on a threshold.However,the choice of threshold in DL greatly impacts the denoising results and the improvement in output SNR.Ramanujan’s sum(s)(RS)is a signal processing tool that exhibits derivative behavior and finds applications in edge detection and noise estimation of signals.Hence,we propose a novel DL method with threshold estimation based on RS to improve the output SNR.In this work,we estimate the noise variance of seismic data based on RS and use it as a threshold value for the DL method to perform denoising.We analyze the results of the proposed work on synthetically generated and field data sets.We perform simulations on noisy seismic data across a wide range of SNR values and tabulate the denoised results using the performance metrics SNR and mean squared error.The results indicate that the proposed method provides superior SNR and reduced mean squared error compared to MAD,SURE-based,and adaptive soft-thresholding techniques. 展开更多
关键词 Seismic denoising Ramanujan sum Dictionary learning 2D seismic data
在线阅读 下载PDF
Banana Peel and Beyond:Transforming Agricultural Waste into Eco-Friendly,Biodegradable Plastics
8
作者 Nageswara Rao Lakkimsetty Lakshmi Jayanthi Juturi +5 位作者 Amarender Reddy Kommula Clement Varaprasad Karu Naladi Ram Babu Dadapeer Doddamani G.Kavitha Rakesh Namdeti 《Journal of Environmental & Earth Sciences》 2025年第5期17-29,共13页
The management of agricultural wastes is essential for resource conservation and environmental sustainability.Due to escalating worries regarding plastic pollution and the surging expenses linked to petroleum-based pl... The management of agricultural wastes is essential for resource conservation and environmental sustainability.Due to escalating worries regarding plastic pollution and the surging expenses linked to petroleum-based plastics,there has been a notable transition towards the creation of biodegradable alternatives sourced from natural materials.Biofibres and bioplastics,especially those derived from agricultural waste,have garnered significant attention for their prospective uses in food packaging,biomedical sciences,and sustainable manufacturing.This study examines the viability of employing banana peel as a natural and environmentally sustainable raw material for the production of biodegradable bioplastic sheets.Due to its abundant polysaccharides and lignocellulosic fibers,banana peel presents advantageous structural and mechanical characteristics for bioplastic manufacturing.Experimental findings demonstrate that bioplastic derived from banana peels has enhanced biodegradability and environmental compatibility relative to traditional synthetic plastics,positioning it as a feasible alternative to mitigate the worldwide plastic waste epidemic.An optimal formulation was constructed using Design Expert software,comprising 55.38 g of banana peel,27.63 g of fish scales,and 20 g of chitosan powder.This formulation improves the film’s tensile strength,flexibility,and degradation rate,ensuring its efficacy in industrial applications including food packaging and molding.The study’s results highlight the promise of bioplastics made from banana peels as an economical and sustainable alternative,decreasing dependence on petroleum-based plastics and alleviating environmental pollution. 展开更多
关键词 Biodegradable Plastics Banana Peel Fish Scale CHITOSAN Design Expert Software
在线阅读 下载PDF
Digital Twins and Cyber-Physical Systems:A New Frontier in Computer Modeling
9
作者 Vidyalakshmi G S Gopikrishnan +2 位作者 Wadii Boulila Anis Koubaa Gautam Srivastava 《Computer Modeling in Engineering & Sciences》 2025年第4期51-113,共63页
Cyber-Physical Systems(CPS)represent an integration of computational and physical elements,revolutionizing industries by enabling real-time monitoring,control,and optimization.A complementary technology,Digital Twin(D... Cyber-Physical Systems(CPS)represent an integration of computational and physical elements,revolutionizing industries by enabling real-time monitoring,control,and optimization.A complementary technology,Digital Twin(DT),acts as a virtual replica of physical assets or processes,facilitating better decision making through simulations and predictive analytics.CPS and DT underpin the evolution of Industry 4.0 by bridging the physical and digital domains.This survey explores their synergy,highlighting how DT enriches CPS with dynamic modeling,realtime data integration,and advanced simulation capabilities.The layered architecture of DTs within CPS is examined,showcasing the enabling technologies and tools vital for seamless integration.The study addresses key challenges in CPS modeling,such as concurrency and communication,and underscores the importance of DT in overcoming these obstacles.Applications in various sectors are analyzed,including smart manufacturing,healthcare,and urban planning,emphasizing the transformative potential of CPS-DT integration.In addition,the review identifies gaps in existing methodologies and proposes future research directions to develop comprehensive,scalable,and secure CPSDT systems.By synthesizing insights fromthe current literature and presenting a taxonomy of CPS and DT,this survey serves as a foundational reference for academics and practitioners.The findings stress the need for unified frameworks that align CPS and DT with emerging technologies,fostering innovation and efficiency in the digital transformation era. 展开更多
关键词 Cyber physical systems digital twin efficiency Industry 4.0 robustness and intelligence
在线阅读 下载PDF
Bias characteristics of cloud diurnal variation in the FGOALS-f3-L model
10
作者 Hongtao Yang Guoxing Chen +1 位作者 Qing Bao Bian He 《Atmospheric and Oceanic Science Letters》 2025年第6期65-70,共6页
Cloud diurnal variation is crucial for regulating cloud radiative effects and atmospheric dynamics.However,it is often overlooked in the evaluation and development of climate models.Thus,this study aims to investigate... Cloud diurnal variation is crucial for regulating cloud radiative effects and atmospheric dynamics.However,it is often overlooked in the evaluation and development of climate models.Thus,this study aims to investigate the daily mean(CFR)and diurnal variation(CDV)of cloud fraction across high-,middle-,low-level,and total clouds in the FGOALS-f3-L general circulation model.The bias of total CDV is decomposed into the model biases in CFRs and CDVs of clouds at all three levels.Results indicate that the model generally underestimates low-level cloud fraction during the daytime and high-/middle-level cloud fraction at nighttime.The simulation biases of low clouds,especially their CDV biases,dominate the bias of total CDV.Compensation effects exist among the bias decompositions,where the negative contributions of underestimated daytime low-level cloud fraction are partially offset by the opposing contributions from biases in high-/middle-level clouds.Meanwhile,the bias contributions have notable land–ocean differences and region-dependent characteristics,consistent with the model biases in these variables.Additionally,the study estimates the influences of CFR and CDV biases on the bias of shortwave cloud radiative effects.It reveals that the impacts of CDV biases can reach half of those from CFR biases,highlighting the importance of accurate CDV representation in climate models. 展开更多
关键词 Cloud fraction Diurnal variation Climate model Model bias dissection Shortwave cloud radiative effects
在线阅读 下载PDF
Bone marrow mesenchymal stem cell-loaded HAMA hydrogel within highly bionic nerve guidance conduits for peripheral nerve regeneration
11
作者 Chao Li Li-Fang Zhu +3 位作者 Ming-Wei Chang Hao Li Shiheng Liu Baolin Wang 《Bio-Design and Manufacturing》 2025年第6期976-993,I0028-I0031,共22页
Nerve guidance conduits(NGCs)effectively support and guide the regeneration of injured nerves.However,traditional NGCs often lack essential growth factors and fail to create a biomimetic microenvironment conducive to ... Nerve guidance conduits(NGCs)effectively support and guide the regeneration of injured nerves.However,traditional NGCs often lack essential growth factors and fail to create a biomimetic microenvironment conducive to nerve regrowth.This study develops a highly bionic nerve guidance conduit(HB-NGC)using hybrid high-voltage electrotechnologies that integrate electrospinning with electrohydrodynamic(EHD)printing.The outer layer consists of electrospun polycaprolactone fibers loaded with carboxyl-multi-walled carbon nanotubes,while the inner layer is composed of highly aligned polycaprolactone fibers created by EHD printing.The tubular core of the HB-NGC is filled with hyaluronic acid methacryloyl(HAMA)hydrogel encapsulating bone marrow mesenchymal stem cells(BMSCs).This highly biomimetic NGC is conductive,capable of guiding axon growth,and sustainably releases growth factors,effectively mimicking the structure,function,and characteristics of natural peripheral nerves.Its distinctive architectural layers provide an exceptional bionic microenvironment by restoring physical pathways,facilitating electrical signal conduction,and supplying an extracellular matrix(ECM)environment enriched with essential growth factors.Additionally,the HB-NGC’s morphology,along with its physicochemical and mechanical properties,effectively bridges the gap between severed nerve ends.In vivo animal studies validate the HB-NGC’s effectiveness,highlighting its significant potential to enhance peripheral nerve regeneration. 展开更多
关键词 BIONIC Bone marrow mesenchymal stem cells(BMSCs) Hyaluronic acid methacryloyl(HAMA)hydrogel Long distance Peripheral nerve regeneration
暂未订购
Lightweight Residual Multi-Head Convolution with Channel Attention(ResMHCNN)for End-to-End Classification of Medical Images
12
作者 Sudhakar Tummala Sajjad Hussain Chauhdary +3 位作者 Vikash Singh Roshan Kumar Seifedine Kadry Jungeun Kim 《Computer Modeling in Engineering & Sciences》 2025年第9期3585-3605,共21页
Lightweight deep learning models are increasingly required in resource-constrained environments such as mobile devices and the Internet of Medical Things(IoMT).Multi-head convolution with channel attention can facilit... Lightweight deep learning models are increasingly required in resource-constrained environments such as mobile devices and the Internet of Medical Things(IoMT).Multi-head convolution with channel attention can facilitate learning activations relevant to different kernel sizes within a multi-head convolutional layer.Therefore,this study investigates the capability of novel lightweight models incorporating residual multi-head convolution with channel attention(ResMHCNN)blocks to classify medical images.We introduced three novel lightweight deep learning models(BT-Net,LCC-Net,and BC-Net)utilizing the ResMHCNN block as their backbone.These models were crossvalidated and tested on three publicly available medical image datasets:a brain tumor dataset from Figshare consisting of T1-weighted magnetic resonance imaging slices of meningioma,glioma,and pituitary tumors;the LC25000 dataset,which includes microscopic images of lung and colon cancers;and the BreaKHis dataset,containing benign and malignant breast microscopic images.The lightweight models achieved accuracies of 96.9%for 3-class brain tumor classification using BT-Net,and 99.7%for 5-class lung and colon cancer classification using LCC-Net.For 2-class breast cancer classification,BC-Net achieved an accuracy of 96.7%.The parameter counts for the proposed lightweight models—LCC-Net,BC-Net,and BT-Net—are 0.528,0.226,and 1.154 million,respectively.The presented lightweight models,featuring ResMHCNN blocks,may be effectively employed for accurate medical image classification.In the future,these models might be tested for viability in resource-constrained systems such as mobile devices and IoMT platforms. 展开更多
关键词 Lightweight models brain tumor breast cancer lung cancer colon cancer multi-head CNN
在线阅读 下载PDF
Solar-powered photothermal-photocatalytic synergistic platform for simultaneous seawater desalination and antibiotic pollutant degradation
13
作者 Liuyan Zhu Wenwen He +11 位作者 Yaru Dang Zeying Jin Dong Cao Heng Zhang Wei Song Yun Bai Ting Shi Lin Zhu Jialin Kang Lu Han Ningning Cao Zhen Yu 《Nano Research》 2025年第12期185-197,共13页
The intensifying global issues of freshwater scarcity and antibiotic contamination,especially in coastal environments,present interconnected threats to both ecosystems and public health.Addressing these issues demands... The intensifying global issues of freshwater scarcity and antibiotic contamination,especially in coastal environments,present interconnected threats to both ecosystems and public health.Addressing these issues demands innovative solutions that synergistically enhance energy efficiency,promote sustainability,and deliver multifunctional benefits.In this study,we present a solar-driven photothermalphotocatalytic synergistic platform(SPSP)constructed from a PF/Co_(3)O_(4)/CNTs@O-ANF composite(PCCO),engineered to achieve simultaneous seawater desalination and antibiotic degradation.The strategically designed 3D hierarchical architecture combines broadband solar absorption,interfacial hydrophobic regulation,and catalytic heterojunction engineering,enabling an elevated water evaporation rate of 1.75 kg·m^(-2)·h^(–1) and efficient degradation of over 98%of tetracycline(TC)across three operational cycles.Outdoor field tests confirmed the system’s operational robustness,producing 6.82 kg·m^(–2)·day^(–1) of purified water.Comprehensive water quality analyses further verified the removal of more than 99%of dissolved salts and organic contaminants,with the collected water exhibiting a neutral pH and complete absence of residual antibiotic activity.More importantly,the purified water facilitated robust growth of Brassica rapa,resulting in a 210% increase in biomass relative to plants irrigated with contaminated water,thereby demonstrating both ecological safety and agricultural applicability.Collectively,this SPSP technology represents a substantial advancement in sustainable water treatment,offering an integrated,energy-efficient solution for producing clean water and effectively remedying antibiotics. 展开更多
关键词 solar-driven evaporation PHOTOCATALYTIC seawater desalination tetracycline(TC) water remediation
原文传递
Management of sessile oak(Quercus petraea(Matt.)Liebl.),a major forest species in Europe
14
作者 Valeriu‑Norocel Nicolescu Torsten Vor +19 位作者 Robert Brus Martina Đodan Sanja Perić Vilém Podrázský Siniša Andrašev Evgeni Tsavkov Sezgin Ayan Cengiz Yücedağ Pande Trajkov Dana Dina Kolevska Cornelia Buzatu‑Goanță Michal Pástor Vladimír Mačejovský Juraj Modranský Marcin Klisz Wojciech Gil Vasyl Lavnyy Palle Madsen Nicola La Porta Debbie Bartlett 《Journal of Forestry Research》 2025年第5期23-59,共37页
Sessile oak(Quercus petraea(Matt.)Liebl.)is widely distributed across most of Europe particularly the hills and lower mountain ranges,so is considered“the oak of the mountains”.This species grows on a wide variety o... Sessile oak(Quercus petraea(Matt.)Liebl.)is widely distributed across most of Europe particularly the hills and lower mountain ranges,so is considered“the oak of the mountains”.This species grows on a wide variety of soils and at altitudes ranging from sea level to 2200 m,especially in Atlantic and sub-Mediterranean climates,and it is sensitive to low winter temperatures,early and late frosts,as well as high summer temperatures.Sessile oak forms both pure and mixed stands especially with broadleaves such as European beech,European hornbeam,small-leaved lime and Acer spp.These form the understorey of sessile oak stands,promoting the natural shedding of lower branches of the oak and protecting the trunk against epicormic branches.Sessile oak is a long-lived,light-demanding and wind-firm species,owing to its taproot and heart-shaped root system.Its timber,one of the most valuable in Europe,is important for fur-niture-making(both solid wood and veneer),construction,barrels,railway sleepers,and is also used as fuelwood.It is one of the few major tree species in Europe that is regener-ated by seed(naturally or artificially)and by stump shoots in high forest,coppice-with-standards and coppice forests.Sessile oak forests are treated in both regular and irregular systems involving silvicultural techniques such as uniform shelterwood,group shelterwood,irregular shelterwood,irregular high forest,coppice-with-standards and simple coppice.Young naturally regenerated stands are managed by weeding,release cutting and cleaning-respacing,keeping the stands quite dense for good natural pruning.Plantations are based on(1)2-4-year old bare-root or container-grown seedlings produced in nurseries using seeds from genetic resources,seed stands and seed orchards.The density of sessile oak plantations(mostly in rows,but also in clusters)is usually between 4000 and 6000 ind.ha^(−1).Sessile oak silviculture of mature stands includes crown thinning,focus-ing on final crop trees(usually a maximum of 100 ind.ha^(−1))and targeting the production of large-diameter and high quality trees at long rotation ages(mostly over 120 years,sometimes 250-300 years).In different parts of Europe,conversion of simple coppices and coppice-with-standards to high forests is continuing.Even though manage-ment of sessile oak forests is very intensive and expensive,requiring active human intervention,the importance of this species in future European forests will increase in the con-text of climate change due to its high resistance to distur-bance,superior drought tolerance and heat stress resistance. 展开更多
关键词 Sessile oak Ecological requirements Timber VULNERABILITIES MANAGEMENT
在线阅读 下载PDF
高压处理对牛肉肌红蛋白及颜色变化的影响 被引量:86
15
作者 马汉军 周光宏 +1 位作者 徐幸莲 D.A.Ledward 《食品科学》 EI CAS CSCD 北大核心 2004年第12期36-39,共4页
室温下不同压力(200、400、600和800MPa),20min处理对绞碎牛肉颜色及肌红蛋白的影响进行了研究。结果显示:随压力的上升,L值增加、a值下降,肌肉逐渐失去红色变为灰棕色。同时,肌红蛋白总量显著降低,高铁肌红蛋白的比例在压力400MPa以上... 室温下不同压力(200、400、600和800MPa),20min处理对绞碎牛肉颜色及肌红蛋白的影响进行了研究。结果显示:随压力的上升,L值增加、a值下降,肌肉逐渐失去红色变为灰棕色。同时,肌红蛋白总量显著降低,高铁肌红蛋白的比例在压力400MPa以上时显著增加。真空包装不能减轻压力导致的变色,而添加亚硝酸钠能对色泽起到稳定作用。压力处理导致色泽变化的原因可能是由于二价铁的肌红蛋白氧化成三价铁的高铁肌红蛋白、球蛋白的变性及结构的变化所致,可通过处理前腌制形成亚硝基肌红蛋白来稳定色泽。 展开更多
关键词 高压处理 牛肉 肌红蛋白 颜色
在线阅读 下载PDF
乌司他丁对双侧全膝关节置换术后患者炎性反应和急慢性疼痛的影响 被引量:7
16
作者 唐帅 徐仲煌 +4 位作者 杨宏 任立英 钱文伟 翁习生 黄宇光 《基础医学与临床》 CSCD 北大核心 2014年第4期514-518,共5页
目的观察乌司他丁对充气式止血带下接受双侧全膝关节置换术(TKA)的患者的围术期炎性反应、术后急性疼痛和慢性疼痛、以及膝关节功能康复速度的影响。方法在大腿止血带下接受双侧TKA的患者40例,随机分为对照组(C组)和试验组(U组),U组静... 目的观察乌司他丁对充气式止血带下接受双侧全膝关节置换术(TKA)的患者的围术期炎性反应、术后急性疼痛和慢性疼痛、以及膝关节功能康复速度的影响。方法在大腿止血带下接受双侧TKA的患者40例,随机分为对照组(C组)和试验组(U组),U组静脉给予乌司他丁。所有患者全身麻醉、术后镇痛和功能康复方案均相同。在不同时间点用酶联免疫吸附(ELISA)法测定IL-6、TNF-α和IL-10浓度,观察静息和活动时VAS疼痛的评分,阿片类药消耗量,膝关节主动屈膝角度和持续被动运动角度及步行30 m所需时间。结果两组患者的一般情况没有差异。U组的部分时间点的炎性因子水平低于C组(P<0.05)。U组术后4 h的静息疼痛评分和舒芬太尼用量显著低于C组(P<0.05)。术后各时间点的功能康复指标均无差异。结论乌司他丁可以减轻围术期炎性反应,降低术后早期的静息疼痛评分,减少阿片类药物用量。 展开更多
关键词 全膝关节置换术 乌司他丁 炎性反应 术后急性疼痛 功能康复
暂未订购
中国花生小核心种质与ICRISAT微核心种质的SSR遗传多样性比较 被引量:20
17
作者 姜慧芳 任小平 +6 位作者 张晓杰 黄家权 雷永 晏立英 廖伯寿 Hari D UPADHYAYA Corley C HOLBROOK 《作物学报》 CAS CSCD 北大核心 2010年第7期1084-1091,共8页
明确花生种质资源的遗传多样性和分布规律,对于发掘优良种质资源,选配优良亲本,拓宽育成品种的遗传基础具有重要意义。核心种质为种质资源的研究、评价和鉴定带来了方便。本研究从206对SSR引物中筛选26对引物对我国花生小核心种质和ICRI... 明确花生种质资源的遗传多样性和分布规律,对于发掘优良种质资源,选配优良亲本,拓宽育成品种的遗传基础具有重要意义。核心种质为种质资源的研究、评价和鉴定带来了方便。本研究从206对SSR引物中筛选26对引物对我国花生小核心种质和ICRISAT微核心种质共466份资源进行了遗传多样性分析,相似系数为0.49~0.99,鉴定出遗传差异最大的种质L2刚果(中国花生资源)与ICG12625(ICRISAT资源),相似系数为0.49。分析结果表明,多粒型花生的多态性信息量(0.761)和遗传多样性指数(0.97~1.11)均最大(平均相似系数最小,0.73~0.76),其次是普通型花生。中国花生种质资源与ICRISAT资源存在较大差异,尤其是ICRISAT的赤道型材料ICG12625,与中国花生资源的差异最大。相似系数和遗传多样性指数的分析结果均表明,我国花生种质资源的遗传多样性比ICRISAT资源丰富。 展开更多
关键词 花生 核心种质 SSR 遗传多样性
在线阅读 下载PDF
利用核心种质发掘及评价花生抗黄曲霉资源 被引量:7
18
作者 姜慧芳 任小平 +5 位作者 王圣玉 张晓杰 黄家权 廖伯寿 Corley C HOLBROOKA Hari D UPADHYAYA 《作物学报》 CAS CSCD 北大核心 2010年第3期428-434,共7页
黄曲霉菌极大地限制全世界的花生生产和产业发展,且生产上抗性品种较少,我国花生育种和生产中的抗性资源缺乏,迫切需要发掘抗黄曲霉种质。本研究以中国花生核心种质561份和ICRISAT微核心种质155份为材料,鉴定了黄曲霉侵染和产毒抗性,发... 黄曲霉菌极大地限制全世界的花生生产和产业发展,且生产上抗性品种较少,我国花生育种和生产中的抗性资源缺乏,迫切需要发掘抗黄曲霉种质。本研究以中国花生核心种质561份和ICRISAT微核心种质155份为材料,鉴定了黄曲霉侵染和产毒抗性,发掘出抗黄曲霉侵染和产毒种质各8份,包括具优良农艺性状的抗黄曲霉产毒种质51002-6。鉴定结果表明,ICRISAT花生微核心种质中抗黄曲霉侵染和产毒种质的频率高于中国花生核心种质;普通型花生资源中抗黄曲霉侵染种质的频率较高,龙生型资源中抗黄曲霉产毒种质的频率较高。根据SSR分析,鉴定出与生产上推广应用的优良品种中花5号、中花6号、中花12和远杂9102遗传距离较远的抗黄曲霉产毒种质ICG12625和抗侵染种质ICG4750,拓宽了我国花生品种改良的遗传基础。根据抗病基因产物的NBS类型保守域设计简并引物对抗黄曲霉种质的DNA进行PCR扩增、克隆、测序和分析,获得了1条RGA片段。 展开更多
关键词 花生核心种质 抗黄曲霉资源 农艺性状 SSR遗传多样性 RGA
在线阅读 下载PDF
SARS继发曲菌感染死亡1例临床病理学观察 被引量:2
19
作者 王慧君 丁彦青 +11 位作者 徐军 杨磊 张文丽 李欣 耿舰 申洪 蔡俊杰 李学锋 康伟 吴正蓉 赵菲 钟南山 《诊断病理学杂志》 CSCD 2003年第3期129-132,i039,共5页
目的 探讨重症急性呼吸综合征 (SARS)的死因和病变特征。方法 常规HE染色 ,组织化学Macchiavello法、MSB、网状纤维、PAS染色法进行观察。结果 SARS增生修复期改变 ;继发性肺曲菌病伴双肺广泛化脓性炎 ,严重的肺组织破坏 ,肺水肿 ,... 目的 探讨重症急性呼吸综合征 (SARS)的死因和病变特征。方法 常规HE染色 ,组织化学Macchiavello法、MSB、网状纤维、PAS染色法进行观察。结果 SARS增生修复期改变 ;继发性肺曲菌病伴双肺广泛化脓性炎 ,严重的肺组织破坏 ,肺水肿 ,肺出血 ,气管、支气管、小支气管血液吸入 ;霉菌性败血症伴全身器官播散性、多发性曲菌性脓肿、局部组织坏死及出血伴纤维素性坏死性血管炎、血栓及霉菌菌栓形成 ;免疫器官抑制 :脾红髓及白髓等淋巴组织严重减少 ,淋巴组织灶状坏死 ;纤维组织增生 ;淋巴结淋巴滤泡减少 ,生发中心消失 ,间质纤维化 ;骨髓粒细胞系、巨核细胞系减少 ,红细胞系灶状增生。结论 患者死于免疫功能抑制继发感染性多器官衰竭。提示对SARS的皮质激素治疗要适时视情慎用。 展开更多
关键词 SARS 曲菌感染 死亡 病理学观察 皮质激素 治疗
暂未订购
水平层理缝岩石物理建模及其地震响应特征 被引量:6
20
作者 陈双全 钟庆良 +3 位作者 李忠平 张敏 赵欣 李向阳 《石油与天然气地质》 EI CAS CSCD 北大核心 2020年第6期1273-1281,1287,共10页
裂缝介质的岩石物理建模及其地震响应特征分析,是利用地震资料进行裂缝性储层预测的重要基础,通过岩石物理建模可以建立起有效的地震反演及储层描述方法。针对非常规页岩油气储层具有的水平层理缝特征,开展了岩石物理建模方法及其地震... 裂缝介质的岩石物理建模及其地震响应特征分析,是利用地震资料进行裂缝性储层预测的重要基础,通过岩石物理建模可以建立起有效的地震反演及储层描述方法。针对非常规页岩油气储层具有的水平层理缝特征,开展了岩石物理建模方法及其地震响应特征研究。利用实际岩样数据与测井数据,采用Voigt-Reuss-Hill(VRH)边界和等效自相容近似(SCA)理论,将非粘土、粘土、孔隙和流体进行组合得到岩石背景介质;结合实际裂缝产状和发育规律信息,通过Chapman多尺度裂缝岩石物理模型引入水平层理缝;采用传播矩阵方法正演得到地震响应。基于此,结合实际工区资料,形成了一套基于多尺度裂缝岩石物理模型的水平层理缝建模方法及技术流程,并在江汉油田页岩油储层中进行了应用研究。正演结果表明:页岩储层的水平层理缝较发育,地震响应具有明显的频变特征,而且水平层理缝的裂缝长度与裂缝密度是影响其地震各向异性最重要的参数,以上参数可以很好地应用于水平层理缝地震预测中。 展开更多
关键词 Chapman模型 频变特征 地震各向异性 水平层理缝 岩石物理建模
在线阅读 下载PDF
上一页 1 2 19 下一页 到第
使用帮助 返回顶部