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Auto Composition System for Two Voice Part Inventions Based on Soft Computational Methods 被引量:1
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作者 周昌乐 蒋旻隽 杜鹏 《Journal of Donghua University(English Edition)》 EI CAS 2010年第2期169-172,共4页
Algorithmic composition is a very popular research field today. Bach's "two voice part invention" is the research object in this paper. The grammar and compositional rules of "invention" are in... Algorithmic composition is a very popular research field today. Bach's "two voice part invention" is the research object in this paper. The grammar and compositional rules of "invention" are introduced first. Then two soft computational methods,genetic algorithms and back propagation (BP) neural network technology,are combined to the experiment on assisting in composing "two voice part inventions". The system presented in this paper is quite effective and satisfactory. 展开更多
关键词 algorithmic composition genetic algorithms back propagration (BP) neural network INVENTION
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Trends in alpha diversity,community composition,and network complexity of rare,intermediate,and abundant bacterial taxa along a latitudinal gradient and their impact on ecosystem multifunctionality 被引量:1
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作者 Rong Tang Shuaifeng Li +3 位作者 Xiaobo Huang Rui Zhang Cong Li Jianrong Su 《Forest Ecosystems》 2025年第4期642-654,共13页
Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions ... Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions affect EMF remain largely unknown.Here,we investigated variation in three measures of diversity(alpha diversity,community composition and network complexity)among rare,intermediate,and abundant taxa across a latitudinal gradient spanning five forest plots in Yunnan Province,China and examined their contributions on EMF.We aimed to characterize the diversity distributions of bacterial groups across latitudes and to assess the differences in the mechanisms underlying their contributions to EMF.We found that multifaceted diversity(i.e.,diversity assessed by the three different metrics)of rare,intermediate,and abundant bacteria generally decreased with increasing latitude.More importantly,we found that rare bacterial taxa tended to be more diverse,but they contributed less to EMF than intermediate or abundant bacteria.Among the three dimensions of diversity we assessed,only community composition significantly affected EMF across all locations,while alpha diversity had a negative effect,and network complexity showed no significant impact.Our study further emphasizes the importance of intermediate and abundant bacterial taxa as well as community composition to EMF and provides a theoretical basis for investigating the mechanisms by which belowground microorganisms drive EMF along a latitudinal gradient. 展开更多
关键词 BACTERIA Ecosystem multifunctionality Alpha diversity Community composition Network complexity Latitudinal gradient
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Longitudinal changes in body composition during palliative systemic chemotherapy and survival outcomes in metastatic colorectal cancer
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作者 Hyehyun Jeong Yousun Ko +6 位作者 Kyung Won Kim Ji Sung Lee Seyoung Seo Sun Young Kim Yong Sang Hong Jeong Eun Kim Tae Won Kim 《World Journal of Gastrointestinal Oncology》 2025年第5期134-147,共14页
BACKGROUND In patients with metastatic colorectal cancer,chemotherapy may lead to changes in body composition,including skeletal muscle quantity and quality,and body fat area and distribution.Longitudinal follow-up da... BACKGROUND In patients with metastatic colorectal cancer,chemotherapy may lead to changes in body composition,including skeletal muscle quantity and quality,and body fat area and distribution.Longitudinal follow-up data in a homogeneous population are required to understand these changes better.AIM To comprehensively evaluate changes in body composition and their prognostic value in patients with metastatic colorectal cancer undergoing palliative chemo-therapy.METHODS This retrospective study included patients with recurrent or metastatic colorectal cancer who received palliative chemotherapy between 2008 and 2017.Computed tomography scans were analyzed at multiple time points(before each new chemotherapy regimen and after discontinuing all chemotherapy).Body composition was analyzed from each scan using artificial intelligence software(AID-UTM,iAID Inc.),and its association with survival was evaluated through time-dependent Cox regression to adjust for time-varying effects.RESULTS This analysis included 1805 patients,with a median age at diagnosis of 57 years,and 62%were male.At first-line chemotherapy initiation,4.7%,30.9%,36.5%,and 37.1%of the patients had sarcopenia,myosteatosis,and visceral and subcutaneous obesity,respectively.During treatment,approximately 54.5%of the patients experienced significant changes in body composition,with 9.1%and 19.2%developing new sarcopenia and myosteatosis,respectively.Sarcopenia and myosteatosis were associated with poorer survival outcomes[hazard ratio(HR)for sarcopenia,2.55(95%CI:2.06-3.16,P<0.001;HR for myosteatosis,2.37(95%CI:2.00-2.82),P<0.001].In contrast,visceral and subcutaneous obesity were associated with improved survival[HR for visceral obesity,0.69(95%CI:0.57-0.82),P<0.001;HR for subcutaneous obesity,0.78(95%CI:0.64-0.95),P=0.015],with no negative impacts observed at higher fat levels.These changes correlated with end-of-life survival time.CONCLUSION Abnormalities and body composition changes were frequently observed during palliative chemotherapy for advanced colorectal cancer;myosteatosis was common.Comprehensive body composition assessment offers valuable prognostic insights without requiring additional testing. 展开更多
关键词 SARCOPENIA Myosteatosis OBESITY Body composition Metastatic colorectal cancer Palliative systemic treatment CHEMOTHERAPY Deep learning Artificial intelligence
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Comparative effectiveness of lifestyle interventions on children's body composition management:A systematic review and network meta-analysis
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作者 Xiwen Su Mohamed A.Hassan +1 位作者 HyunJoon Kim Zan Gao 《Journal of Sport and Health Science》 2025年第1期38-48,共11页
Purpose:This study aimed to provide comparative evidence on the effectiveness of various lifestyle interventions on body composition management for preschool and school-aged children.Methods:PubMed(MEDLINE),Embase,CIN... Purpose:This study aimed to provide comparative evidence on the effectiveness of various lifestyle interventions on body composition management for preschool and school-aged children.Methods:PubMed(MEDLINE),Embase,CINAHL,and Web of Science were systematically searched for this network meta-analysis.Randomized controlled studies(RCTs)that included children aged 4-12 years with no physical or mental conditions;performed at least 1 type of lifestyle intervention;reported change in body mass index(BMI),BMI z-score,or body fat percentage(BFP);and were published between January2010 and August 2023 were included.Results:The final analysis included 91 RCTs with aggregate data for 58,649 children.All interventions were categorized into single-arm approaches(physical activity,diet,and behavioral and informational support)and combined arms approaches(bicomponent and multicomponent treatment).Multicomponent treatment showed significant effectiveness on the reduction of BMI(mean deviation(MD)-0.49,95%confidence interval(95%CI):-0.88 to-0.12),BMI z-score(MD=-0.11,95%CI:-0.18 to-0.04),and BFP(MD=-1.69,95%CI:-2.97 to-0.42)compared to the usual care condition.Bicomponent treatment also significantly reduced BMI(MD=-0.28,95%CI:-0.54 to-0.04)and BMI z-score(MD=-0.07,95%CI:-0.12 to-0.02)compared to usual care.Conclusion:Interventions targeting multiple lifestyle components achieved greater reductions in children's BMI and BFP.Among single-component approaches,physical activity engagement emerged as the most effective.These findings should guide practitioners in recommending comprehensive lifestyle modifications for children.Moreover,children with higher initial BMI and body fat levels tend to exhibit more positive responses to lifestyle interventions aimed at managing obesity. 展开更多
关键词 Lifestyle intervention Body composition Preschool-aged children School-aged children
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Understory floristic composition of planted western white pine stands in the northern Rocky Mountains
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作者 Andrew S.Nelson Theresa B.Jain +3 位作者 Jason Reinhardt Eva K.Strand Nicole Mutchler John Byrne 《Forest Ecosystems》 2026年第1期109-119,共11页
Understory plants are an integral part of forests,serving a variety of functions that help maintain healthy ecosystems.The structure and composition of the understory are influenced by numerous biotic and abiotic fact... Understory plants are an integral part of forests,serving a variety of functions that help maintain healthy ecosystems.The structure and composition of the understory are influenced by numerous biotic and abiotic factors,with light being critical.The introduction of the pathogen Cronartium ribicola,which causes white pine blister rust,into North America in the early 20 th century led to the near total loss of western white pine(Pinus monticola)from moist forests of the Northern Rockies.Management is reintroducing blister rust-resistant western white pine across the landscape,but the effects on the understory are unknown.We examined the effects of stand structure and proportion of western white pine in the overstory on understory diversity of vascular plants in closed canopy stands dominated by blister rust-resistant western white pine across northern Idaho.Habitat series explained the greatest amount of variation(34%)in species presence-absence,while canopy cover accounted for 25%,basal area of all trees for 18%,and the proportion of western white pine composition by 14%.Our analysis revealed positive relationships between the proportion of western white pine in the overstory and both the presence of understory plants and the cover of several understory species.For both the presence and cover,separate sets of thirteen species were found to have a positive relationship with the proportion of western white pine in the overstory,with eight species in common.This research fills a knowledge gap by using data from a range of stands across northern Idaho with varying abundance of western white pine in the overstory to evaluate the relationship between the understory and overstory composition.As land managers plant more western white pine trees,we are likely to see the concomitant increase in understory plant diversity across the landscape,in addition to numerous other benefits,including disturbance resistance and resilience. 展开更多
关键词 Moist conifer forests Understory composition Plant communities BIODIVERSITY Foundational species Hierarchical modeling of species communities
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Analysis relationship between body composition and blood pressure among rural adults
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作者 Yunus Elon Evelin Malinti +1 位作者 Joshua H.L.Tobing Samuel Maju Simanjuntak 《Frontiers of Nursing》 2026年第1期51-60,共10页
Objective:Hypertension is a serious public health concern that is influenced by a variety of body composition parameters.This study examines the associations between body composition metrics and blood pressure(BP)in a... Objective:Hypertension is a serious public health concern that is influenced by a variety of body composition parameters.This study examines the associations between body composition metrics and blood pressure(BP)in a rural population,specifically how variations in body fat distribution and other metrics affect systolic blood pressure(SBP)and diastolic blood pressure(DBP).Methods:A cross-sectional study of 226 participants examined the relationships between body composition metrics—such as total body fat,visceral fat,and body mass index(BMI)—and BP.Correlation and regression analyses were used to assess these relationships.Results:The study found substantial positive correlations between visceral fat and total body fat with both SBP and DBP.Visceral fat was strongly connected with both SBP(r=0.145,P=0.030)and DBP(r=0.331,P<0.01),while total body fat was significantly correlated with DBP(r=0.268,P<0.01)but not SBP.Body composition variables explained 12.8% of the variance in SBP(R^(2)=0.128,P=0.001)and 15.0% in DBP(R^(2)=0.150,P<0.001).Conclusions:The study found substantial connections between body composition,particularly visceral and subcutaneous fat and systolic and DBP.Higher levels of visceral fat were linked to elevate BP.Body composition accounted for a significant amount of BP fluctuation. 展开更多
关键词 blood pressure body composition HYPERTENSION systolic and diastolic blood pressure visceral fat
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Tree community composition modulates early-stage decomposition of standard litter through chemical and physical engineering
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作者 Joachim López Karen Vancampenhout +1 位作者 Bart Muys Quentin Ponette 《Forest Ecosystems》 2026年第1期22-34,共13页
Litter decomposition is an essential ecosystem process influenced by multiple factors,including substrate quality,climate,edaphic environment,and decomposer communities.However,the role of canopy species identity and ... Litter decomposition is an essential ecosystem process influenced by multiple factors,including substrate quality,climate,edaphic environment,and decomposer communities.However,the role of canopy species identity and diversity on leaf litter decomposition in forests remains understudied.By controlling for macroclimate,soil properties,and litter substrate in a mature common garden,we investigated whether a three-month tea bag incubation of standardized green and rooibos tea substrate is driven by canopy tree species characteristics and diversity.Our study hypothesized two primary pathways:a chemical engineering effect,where trees alter soil properties and decomposer communities through litter input,and a physical engineering effect,where tree canopy structure modulates the local microclimate.The results showed that even under uniform macroclimatic and initial soil conditions,mass loss rates varied widely for green tea(27.4%–73.2%)and rooibos tea(6.1%–34.7%),comparable as found in other research between distinct biomes.While substrate quality was the dominant factor,both engineering pathways and,to a minor extent,tree diversity modulated mass losses.For green tea,tree chemical and physical characteristics seemed equally important,while the physical environment showed an increased importance for rooibos.Incubation depth played a key role,where forest floor decomposition rates are more susceptible to temporal climate variations,and soil-layer decomposition rates are less susceptible to climate variations and more determined by tree species identity.Our findings suggest that tea bag experiments focusing solely on topsoil burial may underestimate processes in the forest floor and the mineralorganic boundary layer.This study underscores the critical role of litter substrate quality in decomposition while demonstrating that tree community composition and the associated herbaceous layer,through both chemical and physical engineering pathways,strongly modulate decomposition rates. 展开更多
关键词 Tea bag incubation Early-stage litter decomposition Geographical arboretum Tree species composition
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Multi-scale simplified residual convolutional neural network model for predicting compositions of binary magnesium alloys
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作者 Xu Qin Qinghang Wang +6 位作者 Xinqian Zhao Shouxin Xia Li Wang Jiabao Long Yuhui Zhang Yanfu Chai Daolun Chen 《Journal of Magnesium and Alloys》 2026年第1期117-123,共7页
This study proposes a multi-scale simplified residual convolutional neural network(MS-SRCNN)for the precise prediction of Mg-Nd binary alloy compositions from scanning electron microscope(SEM)images.A multi-scale data... This study proposes a multi-scale simplified residual convolutional neural network(MS-SRCNN)for the precise prediction of Mg-Nd binary alloy compositions from scanning electron microscope(SEM)images.A multi-scale data structure is established by spatially aligning and stacking SEM images at different magnifications.The MS-SRCNN significantly reduces computational runtime by over 90%compared to traditional architectures like ResNet50,VGG16,and VGG19,without compromising prediction accuracy.The model demonstrates more excellent predictive performance,achieving a>5%increase in R^(2) compared to single-scale models.Furthermore,the MS-SRCNN exhibits robust composition prediction capability across other Mg-based binary alloys,including Mg-La,Mg-Sn,Mg-Ce,Mg-Sm,Mg-Ag,and Mg-Y,thereby emphasizing its generalization and extrapolation potential.This research establishes a non-destructive,microstructure-informed composition analysis framework,reduces characterization time compared to traditional experiment methods and provides insights into the composition-microstructure relationship in diverse material systems. 展开更多
关键词 Magnesium alloys composition prediction Scanning electron microscope images Multi-scale simplified residual convolutional neural network
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Nail abnormalities in upper extremity transplantation:Perspectives and insights from systemic diseases and organ transplantation
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作者 Naga Anvesh Kodali Ramu Janarthanan +6 位作者 Zeynep Demir Bedreddin Sazoglu Omer Faruk Dirican Dmitry Tuder Fatih Zor Yalcin Kulahci Vijay S Gorantla 《World Journal of Transplantation》 2026年第1期115-128,共14页
Nail changes following upper extremity transplantation(UET)cannot be overlooked as they possess diagnostic and prognostic relevance in allotransplantation of upper limbs.This comprehensive review explores nail and nai... Nail changes following upper extremity transplantation(UET)cannot be overlooked as they possess diagnostic and prognostic relevance in allotransplantation of upper limbs.This comprehensive review explores nail and nail bed related changes encountered in UET recipients in the literature.The differential diagnosis of nail abnormalities in UET includes a wide range of systemic,local and iatrogenic conditions other than immune responses to the allograft.It requires interdisciplinary evaluation by primary transplant surgeons,pathologists,dermatologists and immunologists.The possible underlying mechanisms of nail pathology in UET and the management are discussed.It also underscores the importance of onychodystrophy and need for timely intervention and to improve outcomes in UET recipients. 展开更多
关键词 Vascularized composite allotransplantation Upper extremity transplantation Hand transplantation Nail abnormalities Onychodystrophy Graft rejection Nailfold capillaroscopy
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A Multi-Scale Cross-Band Defense System Integrating Decoupled Visible,Dynamic Infrared Camouflage and Electromagnetic Shielding
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作者 Junlin Liu Shujuan Tan +4 位作者 Xinrui Yang Jiajie Zhu Xin Yan Tianyu Chen Guangbin Ji 《Nano-Micro Letters》 2026年第4期335-352,共18页
Cross-band camouflage technology is a critical necessity,enabling personnel and equipment to evade detection across evolving surveillance systems,thereby enhancing survivability and mission success.Herein,this work de... Cross-band camouflage technology is a critical necessity,enabling personnel and equipment to evade detection across evolving surveillance systems,thereby enhancing survivability and mission success.Herein,this work develops a layer-structured composite system based on carbon nanotube(CNT)film comprising ionic liquid(IL)interlayer for infrared(IR)modulation and surface-engineered Cu_(2)O nanoparticles for visible camouflage.The CNT/IL/CNT architecture enables reversible IR emissivity switching(Δε≈0.55)through electrically driven ion intercalation/deintercalation within 2 s,while spray-coated Cu_(2)O nanoparticles(100~400 nm diameter)on the top CNT film layer generate rich structure colors with 90%IR transmittance.This spectral-decoupling design overcomes the traditional trade-off between color visibility and IR transmittance observed in pigment-based systems.Remarkably,due to physical interface coupling,the Cu_(2)O-coated layer-structured system maintains exceptional electrical conductivity,enabling simultaneous electromagnetic interference shielding and electrothermal energy conversion.The integrated system demonstrates long-term operational stability.By unifying visible-IR camouflage,electromagnetic protection,and energy management in a lightweight platform,this work provides an important paradigm for cross-band camouflage technologies. 展开更多
关键词 Visible camouflage Adaptive IR camouflage Cu_(2)O/CNT composite film Electrothermal energy conversion EMI shielding
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The Influence of Plant Diversity and Functional Composition on Ecosystem Stability of Four Stipa Communities in the Inner Mongolia Plateau 被引量:66
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作者 白永飞 李凌浩 +1 位作者 黄建辉 陈佐忠 《Acta Botanica Sinica》 CSCD 2001年第3期280-287,共8页
The main purpose of this study was to examine the effects of plant species diversity and functional composition (the identity of the plant functional groups) on ecosystem stability of Stipa, communities in the Inner M... The main purpose of this study was to examine the effects of plant species diversity and functional composition (the identity of the plant functional groups) on ecosystem stability of Stipa, communities in the Inner Mongolia Plateau. The research work was based on a 12-year study (from 1984 to 1995) of species abundance, diversity, and primary productivity of four Stipa communities, i.e. S. baicalensis Roshev., S. grandis P. Smirn., S, krylovii Roshev., and S. klemenzii Roshev. respectively. The Shnnon-Wiener index was used as a measurement of plant diversity, while functional composition was used to differentiate the functional groups that were included in the communities. The plant species of four Stipa communities were classified into functional groups based on the differences in life forms and ecological groups, which influence their performance in resource requirements, seasonality of growth, tolerance to water stress, and life history. Plant species were classified into five functional groups based on their differences in life form, shrubs and half shrubs, perennial bunch grasses, perennial rhizome grasses, forbs, annuals and biennials. Based on their differences in water requirement these species were classified into four functional groups: xerads, intermediate xerads, intermediate mesophytes, and mesophytes. The results showed: 1) Plant species diversity stabilized ecosystem processes. Shannon-Wiener index were 2.401 4, 2.172 0, 1.624 8, 0.354 3 from S. baicalensis community to S. grandis, S. krylovii and S. klemenzii community, respectively. The dynamics of the aboveground net primary productivity (ANPP) for a 12-year's period showed a reverse pattern, the coefficients of variation of the four communities were 21.94%, 20.63%, 29.21% and 39.72% respectively. 2) The Life form functional group component of diversity was a greater determinant of the ecosystem processes than the species component of diversity. The effects of perennial bunch grasses, perennial rhizome grasses and forbs on community stability were highly significant. 3) The ecological group component of diversity was also a great determinant of the ecosystem processes. The effects of xerads, intermediate xerads, and mesophytes on community stability were also very strong. 展开更多
关键词 Inner Mongolia Plateau Stipa communities the aboveground net primary productivity species diversity functional composition
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Composition of Garden Road System in Urban Park
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作者 韦松林 彭璐 《Journal of Landscape Research》 2011年第4期39-41,44,共4页
Based on the idea of system,the paper had analyzed components of garden road system in urban park and their relations from the perspective of function,pattern and facility,and established framework of garden road syst... Based on the idea of system,the paper had analyzed components of garden road system in urban park and their relations from the perspective of function,pattern and facility,and established framework of garden road system for guidance of garden road construction.After introduction of the connotation of garden road system,its attributes were summarized which were isolated elements,integrated collection,clear level and dynamic development;and its functional composition had been concluded from the aspects of practical function and social function.Practical functions contained traffic organization and guidance tour,space division and landscape composition,facility organization and habitat improvement.Social functions consisted of communication and education function.The pattern of garden road system had been introduced in terms of pattern elements,level structure and layout form.Facilities of garden road system had been classified into five categories covering rest facilities,ornamental facilities,light facilities,display facilities and service facilities. 展开更多
关键词 PARK green LAND GARDEN ROAD system composition
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Evolution of nutrient structure and phytoplankton composition in the Jiaozhou Bay ecosystem 被引量:12
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作者 ZHAOShu-jiang JIAONian-zhi +2 位作者 WUChang-wen LIANGBing ZHANGShu-yi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第1期95-102,共8页
The inventories of nutrients in the surface water and large phytoplankton(>69 μm) were analyzed from the data set of JERS ecological database about a typical coastal waters, the Jiaozhou Bay, China, from 1960s for... The inventories of nutrients in the surface water and large phytoplankton(>69 μm) were analyzed from the data set of JERS ecological database about a typical coastal waters, the Jiaozhou Bay, China, from 1960s for N, P and from 1980s for Si. By examining long term changes of nutrient concentration, calculating stoichiometric balance, and comparing diatom composition, Si limitation of diatom production was found to be more possible. The possibility of Si limitation was from 37% in 1980s to 50% in 1990s. Jiaozhou Bay ecosystem is becoming serious eutrophication, with notable increase of NO 2 N, NO 3 N and NH 4 N from 0 1417 μmol/L, 0 5414 μmol/L, 1 7222 μmol/L in 1960s to 0 9551 μmol/L, 3 001 μmol/L, 8 0359 μmol/L in late 1990s respectively and prominent decrease of Si from 4 2614 μmol/L in 1980s to 1 5861 μmol/L in late 1990s; the nutrient structure is controlled by nitrogen; the main limiting nutrient is probably silicon; because of the Si limitation the phytoplankton community structure has changed drastically. 展开更多
关键词 NUTRIENTS Si-limitation stoichiometric ratios species composition Jiaozhou Bay
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Influence of stocking density on growth, body composition and energy budget of Atlantic salmon Salmo salar L. in recirculating aquaculture systems 被引量:6
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作者 刘宝良 刘鹰 +3 位作者 刘子毅 仇登高 孙国祥 李贤 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期982-990,共9页
Atlantic salmon Salmo salar were reared at four stocking densities--high density D1 (final density -39 kg/m^3), medium densities DE (-29 kg/m^3) and D3 (~19 kg/m^3), and low density D4 (-12 kg/m^3)- for 40 day... Atlantic salmon Salmo salar were reared at four stocking densities--high density D1 (final density -39 kg/m^3), medium densities DE (-29 kg/m^3) and D3 (~19 kg/m^3), and low density D4 (-12 kg/m^3)- for 40 days to investigate the effect of stocking density on their growth performance, body composition and energy budgets. Stocking density did not significantly affect specific growth rate in terms of weight (SGRw) but did affect specific growth rate in terms of energy (SGRe). Stocking density significantly influenced the ration level (RLw and RLe), feed conversion ratio (FCRw and FCRe) and apparent digestibility rate (ADR). Ration level and FCRw tended to increase with increasing density. Fish at the highest density D~ and lowest density D4 showed lower FCRe and higher ADR than at medium densities. Stocking density significantly affected protein and energy contents of the body but did not affect its moisture, lipid, or ash contents. The expenditure of energy for metabolism in the low-density and high-density groups was lower than that in the medium-density groups. Stocking density affected energy utilization from the feces but had no effect on excretion rate. The greater energy allocation to growth at high density and low density may be attributed to reduced metabolic rate and increased apparent digestibility rate. These findings provide information that will assist selection of suitable stocking densities in the Atlantic-salmon-farming industry. 展开更多
关键词 stocking density Atlantic salmon GROWTH body composition energy budget recirculatingaquaculture system
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Mixed refrigerant composition shift due to throttle valves opening in auto cascade refrigeration system 被引量:5
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作者 许雄文 刘金平 曹乐 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期199-204,共6页
Auto cascade refrigeration(ACR) cycle with phase separators is widely used in the cryogenic system. The composition of mixed refrigerant has a great effect on the performance of the system. Based on the assumption of ... Auto cascade refrigeration(ACR) cycle with phase separators is widely used in the cryogenic system. The composition of mixed refrigerant has a great effect on the performance of the system. Based on the assumption of infinite volume of phase separator, ACR system with one phase separator is simulated in this paper. The variation of refrigerant composition under different valves opening is obtained. A related experimental system is set up to verify the variation. The result shows that when the valve opening connected to the evaporator increases or the valve opening under the phase separator decreases, the low-boiling component concentration of the working mixture passing through the compressor and condenser increases, while the high-boiling component concentration decreases. Furthermore, the variations of condensation pressure and evaporation pressure under different valves opening are also observed. This paper is helpful to deepen the understanding of ACR system. 展开更多
关键词 Auto cascade REFRIGERATION composition shift THROTTLE
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Effects of long-term straw incorporation on nematode community composition and metabolic footprint in a rice–wheat cropping system 被引量:4
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作者 CHEN Yun-feng XIA Xian-ge +4 位作者 HU Cheng LIU Dong-hai QIAO Yan LI Shuang-lai FAN Xian-peng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第8期2265-2276,共12页
Soil nematode communities can provide valuable information about the structure and functions of soil food webs,and are sensitive to agricultural practices,including short-term straw incorporation.However,currently,suc... Soil nematode communities can provide valuable information about the structure and functions of soil food webs,and are sensitive to agricultural practices,including short-term straw incorporation.However,currently,such effects under longterm straw incorporation conditions at different fertility levels are largely unknown.Thus,we conducted a 13-year ongoing experiment to evaluate the effects of long-term straw incorporation on the structure and functions of the soil food web in low and high fertility soils through analyzing its effects on nematode communities,food web indices and metabolic footprints.Four treatments were included:straw removal(–S)under non-fertilized(–NPK)or fertilized(+NPK)conditions;and straw incorporation(+S)under–NPK or+NPK conditions.Soil samples from a 0–20 cm depth layer were collected when wheat and rice were harvested.Compared with straw removal,straw incorporation increased the abundances of total nematodes,bacterivores,plant-parasites and omnivores-predators,as well the relative abundances of omnivores-predators with increases of 73.06,89.29,95.31,238.98,and 114.61%in–NPK soils and 16.23,2.23,19.01,141.38,and 90.23%in+NPK soils,respectively.Regardless of sampling times and fertilization effects,straw incorporation increased the diversity and community stability of nematodes,as indicated by the Shannon-Weaver diversity index and maturity index.Enrichment and structure index did not show significant responses to straw incorporation,but a slight increase was observed in the structure index.The analysis of nematode metabolic footprints showed that straw incorporation increased the plant-parasite footprint and structure footprint by 97.27 and 305.39%in–NPK soils and by 11.29 and 149.56%in+NPK soils,but did not significantly influence enrichment,bacterivore and fungivore footprints.In conclusion,long-term straw incorporation,particularly under a low fertility level,favored the soil nematodes and regulated the soil food web mainly via a top-down effect. 展开更多
关键词 soil nematodes community composition metabolic footprint straw incorporation rice-wheat cropping system top-down effect
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Evolution of Carbon Isotope Composition in Potential Global Stratotype Section and Point at Luoyixi, South China, for the Base of the Unnamed Global Seventh Stage of Cambrian System 被引量:4
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作者 左景勋 彭善池 +3 位作者 朱学剑 祁玉平 林焕令 杨显峰 《Journal of China University of Geosciences》 SCIE CSCD 2008年第1期9-22,共14页
This work deals with the evolution of carbon isotope composition in the Luoyixi (罗依溪) Section, a candidate of the Global Standard Stratotype-section and Point (GSSP), defining the base of the as-yet-undefined s... This work deals with the evolution of carbon isotope composition in the Luoyixi (罗依溪) Section, a candidate of the Global Standard Stratotype-section and Point (GSSP), defining the base of the as-yet-undefined seventh stage of Cambrian System at the first appearance of the cosmopolitan agnostoid Lejopyge iaevigata. This level is favored in a vote of International Subcommission on Cambrian Stratigraphy (ISCS) as the biohorizon for defining the base of a global stage. Two hundred and sixty-four samples for carbon and oxygen isotope analysis have been collected from the carbonate successions at an interval of 0.25 to 0.5 m in this section. Results of the carbon isotope data exhibit a remarkable disciplinarian trend. The pattern of the carbon isotope evolution is gently undulant with a relatively long period during the underlying Drumian Stage, and then the values of δ13C fluctuate sharply with a short period in provisional seventh stage. The onset of sharp fluctuation in the δ13C values begins at the proposed GSSP level, defining the base of the global seventh stage, where δ13C values change from a gentle trend to a sharp trend. Distinct covariant-relationships among δ13C,δ18O, and sea level fluctuations suggest that a warming change in paleoclimate took place during the early global seventh stage, which led to a positive shift in δ13C values. 展开更多
关键词 carbon isotope composition global seventh stage of Cambrian system Luoyixi Section northwestern Hunan (湖南).
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Spatial structure and species composition of soil seed banks in moving sand dune systems of northeast China 被引量:2
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作者 Chunping Miao Xuehua Li +2 位作者 Meiyu Jia Xu Han Deming Jiang 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第1期75-80,共6页
Soil seed banks can provide a mechanistic for understanding the recruitment dynamics and can inform conservation management of ecosystems. To investigate the contribution of soil seed banks to vegetation restoration i... Soil seed banks can provide a mechanistic for understanding the recruitment dynamics and can inform conservation management of ecosystems. To investigate the contribution of soil seed banks to vegetation restoration in moving sand dune systems, we compared seed structure and species similarity between soil seed banks and standing vegetation among moving sand dunes, ecotones and dune slacks in northeast China. Average seed density in dune slacks was greater than in ecotones or moving sand dunes. Seed density in the soil layer of 0-10 cm was greater than at 10-20 cm both in the moving sand dunes and the eco- tones, but seed densities were similar at depths of 10-20 and 20-30 cm in moving sand dunes. Moreover, the spatial autocorrelation of seed density on moving sand dunes was weak but was strong on the ecotones and dune slacks. The species in the soil seed bank of moving sand dune systems were nearly all annuals, and the low similarity was mainly due to the lack of perennial species that were common in standing vegetation. Consequently, vegetation restoration cannot mainly rely on the soil seed banks in the movingsand dunes and more attention should be paid to protection of the dune slacks because they are the main source of seed disperse and seedling recruitment in moving sand dune systems. 展开更多
关键词 compositional similarity Seed density Seedling recruitment Species composition Horqin sandyland
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Automated body composition analysis system based on chest CT for evaluating content of muscle and adipose 被引量:2
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作者 YANG Jie LIU Yanli +2 位作者 CHEN Xiaoyan CHEN Tianle LIU Qi 《中国医学影像技术》 CSCD 北大核心 2024年第8期1242-1248,共7页
Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were col... Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were collected(segmented dataset),and chest CT data of 984 patients were screened from the COVID 19-CT dataset(10 cases were randomly selected as whole test dataset,the remaining 974 cases were selected as layer selection dataset).T7—T8 layer was classified based on convolutional neural network(CNN)derived networks,including ResNet,ResNeXt,MobileNet,ShuffleNet,DenseNet,EfficientNet and ConvNeXt,then the accuracy,precision,recall and specificity were used to evaluate the performance of layer selection dataset.The skeletal muscle(SM),subcutaneous adipose tissue(SAT),intermuscular adipose tissue(IMAT)and visceral adipose tissue(VAT)were segmented using classical fully CNN(FCN)derived network,including FCN,SegNet,UNet,Attention UNet,UNET++,nnUNet,UNeXt and CMUNeXt,then Dice similarity coefficient(DSC),intersection over union(IoU)and 95 Hausdorff distance(HD)were used to evaluate the performance of segmented dataset.The automatic body composition analysis system was constructed based on optimal layer selection network and segmentation network,the mean absolute error(MAE),root mean squared error(RMSE)and standard deviation(SD)of MAE were used to evaluate the performance of automatic system for testing the whole test dataset.Results The accuracy,precision,recall and specificity of DenseNet network for automatically classifying T7—T8 layer from chest CT images was 95.06%,84.83%,92.27%and 95.78%,respectively,which were all higher than those of the other layer selection networks.In segmentation of SM,SAT,IMAT and overall,DSC and IoU of UNet++network were all higher,while 95HD of UNet++network were all lower than those of the other segmentation networks.Using DenseNet as the layer selection network and UNet++as the segmentation network,MAE of the automatic body composition analysis system for predicting SM,SAT,IMAT,VAT and MAE was 27.09,6.95,6.65 and 3.35 cm 2,respectively.Conclusion The body composition analysis system based on chest CT could be used to assess content of chest muscle and adipose.Among them,the UNet++network had better segmentation performance in adipose tissue than SM. 展开更多
关键词 body composition THORAX muscle skeletal adipose tissue deep learning tomography X-ray computed
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Elemental Composition Method in Thermodynamics of Mul- tireaction Systems (I) Molar Number, Thermodynamic Properties and Partial Properties Relations 被引量:1
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作者 林金清 李浩然 韩世钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第1期100-104,共5页
When species in the solution undergo multiple chemical reactions, the solution may be treated as a solution of all species actually present or as a hypothetical solution composed of elemental species. Based on the fu... When species in the solution undergo multiple chemical reactions, the solution may be treated as a solution of all species actually present or as a hypothetical solution composed of elemental species. Based on the fundamental thermodynamic principle, the relationships of mole numbers, molar fractions, thermodynamic properties, partial molar properties, potential and fugacity between the hypothetical solution of elemental species and the equilibrated solution of actual species were derived. The hypothetical elemental solution provides a way of reducing the dimensionality of problem, simplifying the analysis and visualizing the phase behavior. 展开更多
关键词 elemental composition dimension reduction multireaction phase equilibrium THERMODYNAMICS
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