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文章速递Multilayer network analyses as a toolkit for measuring social structure 认领
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作者 Kelly R.FINN 《动物学报:英文版》 SCIE CAS CSCD 北大核心 2021年第1期81-99,共19页
The formalization of multilayer networks allows for new ways to measure sociality in complex social systems,including groups of animals.The same mathematical representation and methods are widely applicable across fie... The formalization of multilayer networks allows for new ways to measure sociality in complex social systems,including groups of animals.The same mathematical representation and methods are widely applicable across fields and study systems,and a network can represent drastically different types of data.As such,in order to apply analyses and interpret the results in a meaningful way the researcher must have a deep understanding of what their network is representing and what parts of it are being measured by a given analysis.Multilayer social networks can represent social structure with more detail than is often present in single layer networks,including multiple"types"of individuals,interactions,or relationships,and the extent to which these types are interdependent.Multilayer networks can also encompass a wider range of social scales,which can help overcome complications that are inherent to measuring sociality.In this paper,I dissect multilayer networks into the parts that correspond to different components of social structures.I then discuss common pitfalls to avoid across different stages of multilayer network analyses-some novel and some that always exist in social network analysis but are magnified in multi-layer representations.This paper serves as a primer for building a customized toolkit of multilayer network analyses,to probe components of social structure in animal social systems. 展开更多
关键词 animal behavior multilayer networks relationships sociality social networks social structure subgroups
文章速递A framework to evaluate whether to pool or separate behaviors in a multilayer network 认领
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作者 Annemarie VAN DER MAREL Sanjay PRASHER +4 位作者 Chelsea CARMINITO Claire L.O'CONNELL Alexa PHILLIPS Bryan M.KLUEVER Elizabeth A.HOBSON 《动物学报:英文版》 SCIE CAS CSCD 北大核心 2021年第1期101-111,共11页
A multilayer network approach combines different network layers,which are connected by interlayer edges,to create a single mathematical object.These networks can contain a variety of information types and represent di... A multilayer network approach combines different network layers,which are connected by interlayer edges,to create a single mathematical object.These networks can contain a variety of information types and represent different aspects of a system.However,the process for selecting which information to include is not always straightforward.Using data on 2 agonistic behaviors in a captive population of monk parakeets(Myiopsitta monachus),we developed a framework for investigating how pooling or splitting behaviors at the scale of dyadic relationships(between 2 individuals)affects individual-and group-level social properties.We designed 2 reference models to test whether randomizing the number of interactions across behavior types results in similar structural patterns as the observed data.Although the behaviors were correlated,the first reference model suggests that the 2 behaviors convey different information about some social properties and should therefore not be pooled.However,once we controlled for data sparsity,we found that the observed measures corresponded with those from the second reference model.Hence,our initial result may have been due to the unequal frequencies of each behavior.Overall,our findings support pooling the 2 behaviors.Awareness of how selected measurements can be affected by data properties is warranted,but nonetheless our framework disentangles these efforts and as a result can be used for myriad types of behaviors and questions.This framework will help researchers make informed and data-driven decisions about which behaviors to pool or separate,prior to using the data in subsequent multilayer network analyses. 展开更多
关键词 behavioral interactions monk parakeet Myiopsitta monachus network analysis social context social relationships
Information for Authors 认领
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《动物分类学报:英文版》 2021年第1期I0001-I0002,共2页
The current journal is mainly focused in zoological systematics.According to Systematics Agenda 2000(1994),systematics is the science built on the following tasks:Taxonomy-the science of discovering,describing,and cla... The current journal is mainly focused in zoological systematics.According to Systematics Agenda 2000(1994),systematics is the science built on the following tasks:Taxonomy-the science of discovering,describing,and classifying species or groups of species(together termed taxa);Phylogenetic analysis-the discovery of the evolutionary relationships among a group of species;and Classification-the grouping of species,ultimately on the basis of evolutionary relationships. 展开更多
关键词 relationships. classify describing
Prediction of load-displacement performance of grouted anchors in weathered granites using FastICA-MARS as a novel model 认领
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作者 Hao Shen Jinhui Li +1 位作者 Sixin Wang Zewei Xie 《地学前缘:英文版》 SCIE CAS 2021年第1期415-423,共9页
With the rising needs of better prediction of the load-displacement performance of grouted anchors in an era of developing large-scale underground infrastructures,the existing methods in literature lack an accurate an... With the rising needs of better prediction of the load-displacement performance of grouted anchors in an era of developing large-scale underground infrastructures,the existing methods in literature lack an accurate analytical model for the real-life projects or rigorous understanding of the parameters such as grouting pressures.This paper proposes Fast ICA-MARS as a novel data-driven approach for the prediction of the load-displacement performance of uplift-resisting grouted anchors.The hybrid and data-driven Fast ICA-MARS approach integrates the multivariate adaptive regression splines(MARS)technique with the Fast ICA algorithm which is for Independent Component Analysis(ICA).A database of 4315 observations for 479 different anchors from 7 different projects is established.The database is then used to train,validate and compare the Fast ICA-MARS approach with the classical MARS approach.The developed Fast ICA-MARS model can provide more accurate predictions than MARS.Moreover,the developed Fast ICA-MARS model is easy to interpret since the evaluation of the parameter importance of the independent components can be conducted along with the considerations of the correlations with the original variables.It is noteworthy to point out that the grouting pressures play a central role in the proposed model,which is considered of paramount importance in engineering practices but has not been properly taken into account in any prior analytical or empirical predictive models for the load-displacement relationships. 展开更多
关键词 Grouted anchors Load-displacement relationships Pull-out tests FASTICA MARS
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Synthesis and Insecticidal Evaluation of Novel Anthranilic Diamides Derivatives Containing 4-Chlorine Substituted N-Pyridylpyrazole 认领
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作者 Huangong Li Yangyang Zhao +6 位作者 Pengwei Sun Li Gao Yuxin Li Lixia Xiong Na Yang Sha Zhou Zhengming Li 《中国化学:英文版》 SCIE CAS 2021年第1期75-80,共6页
To search for potent insecticides targeting at ryanodine receptors(RyRs),a series of novel anthranilic diamides analogs containing 4-chlorine N-pyridylpyrazole were designed and synthesized.Their insecticidal activiti... To search for potent insecticides targeting at ryanodine receptors(RyRs),a series of novel anthranilic diamides analogs containing 4-chlorine N-pyridylpyrazole were designed and synthesized.Their insecticidal activities were evaluated and the preliminary struc ture-activity relationships(SARs)were discussed.The insecticidal results showed that some of the compounds(8a-8h,8m,8n)exhibited good larvicidal activities against oriental armyworm at 2.5 mg·L^(-1),and compound 8m possessed 60%insecticidal activityat 0.5 mg·L^(-1).For diamondback moth,8m exhibited better activity than Chlorantraniliprole at a hundred fold preference. 展开更多
关键词 Synthesis design Anthranilic diamides Insecticidal activity RyRs Structure-activity relationships
论我国高校创业教育高质量发展的十大关系 认领
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作者 徐小洲 梅伟惠 韩冠爽 《高等工程教育研究》 北大核心 2021年第1期155-161,共7页
高质量创业教育是实施创新驱动发展战略、促进经济提质增效升级的迫切需要。我国高校创业教育20多年来取得了显著成就。新时代高质量、可持续发展成为创业教育的主题。未来发展需进一步厘清全球与本土、学校与社会、数量与质量、理论与... 高质量创业教育是实施创新驱动发展战略、促进经济提质增效升级的迫切需要。我国高校创业教育20多年来取得了显著成就。新时代高质量、可持续发展成为创业教育的主题。未来发展需进一步厘清全球与本土、学校与社会、数量与质量、理论与实践、素质与技能、广度与深度、短效与长效、教师与导师、就业与创业、赛场与市场等十大关系。分析创业教育十大关系的背景与主要问题,据此提出针对性改革建议,为推进高校创业教育内涵发展提供启示。 展开更多
关键词 创业教育 质量 关系 策略
A theory to link relationships of stand volume,density,mean diameter and height in forestry data 认领
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作者 Vladimir L.Gavrikov 《林业研究:英文版》 SCIE CAS 2021年第1期15-20,共6页
In this study,a geometric model of a growing forest stand has been explored.The basic relationships considered link stand volume and stand density,diameter at breast height(DBH),mean DBH and mean height.The model prov... In this study,a geometric model of a growing forest stand has been explored.The basic relationships considered link stand volume and stand density,diameter at breast height(DBH),mean DBH and mean height.The model provides simple formulas connecting the exponents of all the relationships.Application of the formulas to real forestry data provided a high level of predictions of an exponent from two others measured through regressions from empirical data.The Pinus sylvestris L.data were of a static nature,a collection of individual stands,while the Pseudotsuga menziesii(Mirb.)Franco data were dynamic,representing forest stand development over time.The ability of the model to predict exponents in the empirical data implies,on the one hand,a substantial level of similarity between the model and the forestry data.And,on the other hand,the model gives an example in which parameters of one relationship may be linked to parameters of another.Supposedly this kind of‘relationship between relationships’may be observed in forest stands undergoing active growth and competition-induced self-thinning. 展开更多
关键词 Relationship between relationships Selfthinning Forestry data ALLOMETRY Scots pine Douglasfir
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Examination of Countermeasures in a Ward: Novice Nurses’ Perception of Issues Relating to Senior Nurses 认领
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作者 Kozue Kamijo 《护理学期刊(英文)》 2020年第3期209-218,共10页
Purpose: In Japan, demand for nursing is high. However, some novice nurses are unable to adapt to the workplace, and subsequently quit. This study aimed at clarifying relationship issues between novice and senior nurs... Purpose: In Japan, demand for nursing is high. However, some novice nurses are unable to adapt to the workplace, and subsequently quit. This study aimed at clarifying relationship issues between novice and senior nurses and examining measures that could be enforced in wards for novice nurses based on the results. Methods: An inductive analysis was conducted on qualitative data from semi-structured interviews with 11 newly hired nurses who had recently graduated from nursing school. The study period was from November 2016 to March 2017. Results: The analysis generated the following three themes related to potential workplace maladaptation: 1) Adaptation to the workplace: difficulty in forming relationships with senior nurses and adapting, 2) Workplace education system: education by preceptors and senior nurses, 3) Professional stance: qualities as a nurse. Conclusion: The results indicated that novice nurses had difficulties in adapting to the workplace as well as its education system in wards. Hence, it was necessary to create habits that would not overly burden others, but instead, spread the rules of the organization, help novice nurses to understand their responsibilities, and assist them in overcoming challenges. 展开更多
关键词 NEWLY Graduated Nurses WORKPLACE RELATIONSHIPS New Hire Training STYLING WORKPLACE Adaptation
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Physico-Chemical Soil Properties and Their Correlations with Maize and Cassava Production in Ebonyi, Nigeria 认领
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作者 Fidelis Chinazor Okorie John Didacus Njoku +1 位作者 Emmanuel Uzoma Onweremadu Martin Chidinma Iwuji 《美国气候变化期刊(英文)》 2020年第1期34-51,共18页
This study analyzed relationships between soil properties and food crop production in Ebonyi State of southeast Nigeria. Free survey was conducted after three zones (Agbaja, Akaeze and Ikwo) in the state were purposel... This study analyzed relationships between soil properties and food crop production in Ebonyi State of southeast Nigeria. Free survey was conducted after three zones (Agbaja, Akaeze and Ikwo) in the state were purposely selected for representation of the soil sampling. Two types of sampling were conducted;Auger sampling at 0 - 20 and 20 - 40 cm depths and soil profile sampling. Annual crop yield data on maize and cassava for the state from 1988 to 2017 were collected from Agriculture Development Program. Variations in properties among soil horizons were obtained using coefficient of variations while soil parameters were regressed against crop yields to establish their relationships. Results showed that fine sand, total sand, bulk density, total porosity, soil pH, and available phosphorus significantly (p = 0.05) differ from 0 - 20 cm and 20 - 40 cm depths. Also, cassava yield correlated negatively with base saturation, and organic matter at 0.05 probability level;with exchangeable Ca and Na at 0.01 probabilities level but correlated positively with bulk density and available water capacity at 0.01 and 0.05 probability levels, respectively. Similarly, maize yield correlated negatively with available phosphorus and total nitrogen at 0.05 probability level;and with total porosity and exchangeable Ca at 0.01 probability level;and then correlated positively with available water capacity, and bulk density, at 0.01 probability level;with coarse sand at 0.05 probability level. However, soils of Ebonyi State are fertile but some of the chemical properties are still low, therefore, it is paramount to improve the quality of the soil to achieve improved food security in the state. 展开更多
关键词 Soil Parameters CROP Yield Relationships Food Security Ebonyi State NIGERIA
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Mean Difference and Mean Deviation of Tukey Lambda Distribution 认领
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作者 Giovanni Girone Antonella Massari +1 位作者 Fabio Manca Angela Maria D’Uggento 《应用数学(英文)》 2020年第8期771-778,共8页
The purpose of this paper is to broaden the knowledge of mean difference and,<span><span><span style="font-family:;" "=""> </span></span></span><span sty... The purpose of this paper is to broaden the knowledge of mean difference and,<span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">in particular, of an important distribution model known as Tukey lambda, which is generally used to choose a model to fit data.</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">We have obtained compact formulas, which are not yet reported in literature, of mean deviation and mean difference related to the said distribution model.</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">These results made it possible to analyze the relationships among variability indexes, namely standard deviation, mean deviation and mean difference, regarding Tukey lambda model.</span></span></span> 展开更多
关键词 Mean Difference Mean Deviation Tukey Lambda Distribution Variability Indexes’ Relationships
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Interplanting Some Soybean Cultivars with Mandarin Trees in Sandy Soil 认领
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作者 M. A. F. Selim Y. A. A. Hefny +1 位作者 Eman I. Abdel-Wahab Marwa Kh. A. Mohamed 《农业科学(英文)》 2020年第1期88-110,共23页
Two-year field experiments were carried out at El-Kassasen Horticultural Research Station, Agricultural Research Center (ARC), Ismailia government, Egypt, during 2018 and 2019 summer seasons to evaluate some soybean c... Two-year field experiments were carried out at El-Kassasen Horticultural Research Station, Agricultural Research Center (ARC), Ismailia government, Egypt, during 2018 and 2019 summer seasons to evaluate some soybean cultivars for interplanting with mandarin trees to achieve high productivity of both crops, land usage and profitability under sandy soil conditions. The treatments were the combinations of two cropping systems (interplanting and solid cultures) and five soybean cultivars (Giza 21, Giza 22, Giza 35, Giza 82 and Giza 111). A strip plot design with three replications was used. Interplanting soybean cultivar Giza 22 with mandarin trees gave a higher total count of rhizobia in rhizosphere of mandarin roots after 75 days from soybean sowing than the other treatments in both seasons. The highest fruit weight and volume, total soluble solids (T.S.S.), fruit yields per tree and per ha were obtained by growing soybean cultivar Giza 22 or Giza 111 with mandarin compared with the other treatments in both seasons. With respect to soybean crop, interplanting soybean with mandarin trees decreased percentages of light intensity at the middle and bottom of the plant, chlorophylls a and b, as well as, plant dry weight after 75 days from soybean sowing compared with those of solid culture in both seasons. Soybean cultivars Giza 22 and Giza 82 had higher light intensity at the middle and bottom of the plant, as well as chlorophyll a, meanwhile soybean cultivars Giza 22 and Giza 111 had higher plant dry weight than the other soybean cultivars after 75 days from soybean sowing in both seasons. Soybean cultivar Giza 22 and Giza 111 had higher plant dry weight than the other soybean cultivars under interplanting and solid plantings in both seasons. Interplanting soybean with mandarin trees decreased soybean seed yield and its attributes compared with soybean solid culture in both seasons. Soybean cultivars Giza 111 and Giza 22 gave a higher number of pods per plant, seed yields per plant and per ha than the other cultivars 展开更多
关键词 INTERPLANTING MANDARIN Soybean CULTIVARS Total COUNT of RHIZOBIA COMPETITIVE Relationships Financial Return
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Pharmacochemical Aspects of the Evolution from Erythromycin to Neomacrolides, Ketolides and Neoketolides 认领
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作者 Ouattara Mahama Coulibaly Songuigama N’Guessan Deto Jean-Paul 《药物化学期刊(英文)》 2020年第3期57-112,共56页
Antibiotic macrolides are experiencing renewed interest in anti-infective therapy since the advent of ketolides. This therapeutic class was introduced in order to broaden the narrow antibacterial spectrum of macrolide... Antibiotic macrolides are experiencing renewed interest in anti-infective therapy since the advent of ketolides. This therapeutic class was introduced in order to broaden the narrow antibacterial spectrum of macrolides and to cope with the emergence of germs resistant to Erythromycin A and its hemisynthetic derivatives or neomacrolides (Clarithromycin, Roxithromycin, Azithromycin, Dirithromycin). From a pharmacochemical point of view, ketolides were first of all obtained by operating chemical modulations on Erythromycin A to obtain the neomacrolides, then, by replacing the neutral sugar (<em>L</em>-cladinose) in <em>C</em>3 by a ketone function coupled with the creation of an oxazolidinone like heterocycle in <em>C</em>11 and <em>C</em>12 in place of the hydroxyls present in these positions (Telithromycin, Cethromycin, Solithromycin). These modulations have enabled the improvement of the chemical stability of ketolides in gastric acid medium and increase their affinity for the ribosomal target, hence the broadening of their spectrum of action towards Gram positive germs including strains resistant to other macrolides and to neomacrolides. Therefore, the objective of this systematic review is to report the various pharmacochemical aspects undertaken since 1952 in the macrolide series based on the structure of Erythromycin A. These aspects will focus on the pharmacomodulations that have led, year after year, to the optimization of stability, the improvement of the pharmacodynamic and pharmacokinetic profile and that have allowed the development of neomacrolides, ketolides and neoketolides, which are today essential in the management of severe bronchopulmonary infections. 展开更多
关键词 Pharmacochemistry ERYTHROMYCIN Neomacrolide KETOLIDE Neoketolide Structure-Activity Relationships
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Chemoinformatic Resources for Organometallic Drug Discovery 认领
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作者 José L. Medina-Franco Yesenia Cruz-Lemus Yazmin Percastre-Cruz 《计算分子生物学(英文)》 2020年第1期1-11,共11页
Medicinal Organometallic Chemistry keeps contributing to drug discovery efforts including the development of diagnostic compounds. Despite the limiting issues of metal-based molecules, e.g., such as toxicity, there ar... Medicinal Organometallic Chemistry keeps contributing to drug discovery efforts including the development of diagnostic compounds. Despite the limiting issues of metal-based molecules, e.g., such as toxicity, there are drugs approved for clinical use and several others are under clinical and pre-clinical development. Indeed, several research groups continue working on organometallic compounds with potential therapeutic applications. For arguably historical reasons, chemoinformatic methods in drug discovery have been applied thus far mostly to organic compounds. Typically, metal-based molecules are excluded from compound data sets for analysis. Indeed, most software and algorithms for drug discovery applications are focused and parametrized for organic molecules. However, considering the emerging field of material informatics, the objective of this Commentary we emphasize the need to develop cheminformatic applications to further develop metallodrugs. For instance, one of the starting points would be developing a compound database of organometallic molecules annotated with biological activity. It is concluded that chemoinformatic methods can boost the research area of Medicinal Organometallic Chemistry. 展开更多
关键词 CHEMINFORMATICS Chemical Space D-InoDB Drug Discovery MEDICINAL ORGANOMETALLIC CHEMISTRY MEDICINAL INORGANIC CHEMISTRY Metal-Based Compounds STRUCTURE-ACTIVITY Relationships
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Competitive Relationships and Yield Advantage of Intercropping Faba Bean with Sugar Beet under Bio-Organic Additives and Mineral Nitrogen Fertilizer Rates 认领
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作者 Y. E. El-Ghobashi A. E. M. Eata 《农业科学(英文)》 2020年第4期369-389,共21页
A field experiment was conducted at El-Serw Agricultural Research Station, Damietta Governorate, Egypt during 2016/2017 and 2017/2018 seasons to reduce mineral N inputs of sugar beet with increased land use efficiency... A field experiment was conducted at El-Serw Agricultural Research Station, Damietta Governorate, Egypt during 2016/2017 and 2017/2018 seasons to reduce mineral N inputs of sugar beet with increased land use efficiency and profitability under intercropping conditions. Seven treatments included five treatments (90 kg nitrogen “N” + 30 m3 farm yard manure “FYM”/fad, 80 kg N +30 m3 FYM/fad, 70 kg N +30 m3 FYM/fad and 400 g of Cerealine + 30 m3 FYM/fad for intercropping faba bean cultivar Spanish with sugar beet cultivar Gloria) and two treatments (90 and 20 kg N/fad for solid culture of sugar beet and faba bean, respectively, as recommended mineral N fertilizer rate) were compared in a randomized complete block design with three replications. Solid culture of sugar beet with the application of recommended rate (90 kg N/fad) gave the highest top, root and sugar yields/fad, as well as the percentage of purity compared with the other treatments in both seasons. Intercropping faba bean with sugar beet plants with application of 90 kg N + 30 m3 FYM/fad gave the highest number of leaves/plant, leaf area/plant, root length, root diameter and root weight/plant followed by intercropped sugar beet plants that fertilized with 80 kg N + 30 m3 FYM/fad compared with the other treatments in both seasons. On the other hand, intercropped sugar beet that received 400 g of Cerealine + 30 m3 FYM/fad had the highest percentages of T.S.S. and sucrose followed by 70 kg N + 30 m3 FYM/fad compared with the other treatments in both seasons. Solid culture of faba bean with the application of 20 kg N/fad gave the highest plant height, number of seeds/pod and seed yield/fad, meanwhile the highest number of branches/plant and pod length were achieved by intercropping faba bean with sugar beet with application of 90 kg N + 30 m3 FYM/fad followed by intercropped faba bean plants that fertilized with 80 kg N + 30 m3 FYM/fad compared with the other treatments in both seasons. However, intercropped faba bean plants that fertilized with 70 kg N 展开更多
关键词 INTERCROPPING Sugar BEET Faba Bean Mineral N Fertilizer FYM Cerealine COMPETITIVE RELATIONSHIPS INTERCROPPING Economic ADVANTAGE
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Functional Brain Network Learning Based on Spatial Similarity for Brain Disorders Identification 认领
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作者 Lei Sun Tingting Guo 《应用数学与应用物理(英文)》 2020年第11期2427-2437,共11页
Functional brain network (FBN) measures based on functional magnetic resonance imaging (fMRI) data, has become important biomarkers for early diagnosis and prediction of clinical outcomes in neurological diseases, suc... Functional brain network (FBN) measures based on functional magnetic resonance imaging (fMRI) data, has become important biomarkers for early diagnosis and prediction of clinical outcomes in neurological diseases, such as Alzheimer’s diseases (AD) and its prodromal state (<em>i</em>.<em>e</em>., Mild cognitive impairment, MCI). In the past decades, researchers have developed numbers of approaches for FBN estimation, including Pearson’s correction (PC), sparse representation (SR), and so on. Despite their popularity and wide applications in current studies, most of the approaches for FBN estimation only consider the dependency between the measured blood oxygen level dependent (BOLD) time series, but ignore the spatial relationships between pairs of brain regions. In practice, the strength of functional connection between brain regions will decrease as their distance increases. Inspired by this, we proposed a new approach for FBN estimation based on the assumption that the closer brain regions tend to share stronger relationships or similarities. To verify the effectiveness of the proposed method, we conduct experiments on a public dataset to identify the patients with MCIs from health controls (HCs) using the estimated FBNs. Experimental results demonstrate that the proposed approach yields statistically significant improvement in seven performance metrics over using the baseline methods. 展开更多
关键词 Functional Brain Network Pearson’s Correction Sparse Representation Spatial Relationships SIMILARITY Mild Cognitive Impairment
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The Amplification and Application of Ribosomal RNA (rDNA) Gene Sequences of <i>Blidingia minima</i>(Chlorophyta, Blidingia) 认领
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作者 Yuan Ao Weijie Shen +3 位作者 Anxiang Yuan Yi Yin Yuan He Songdong Shen 《海洋科学期刊(英文)》 2020年第3期177-190,共14页
<span style="font-family:Verdana;">The sequence of the ribosomal RNA gene (rDNA) plays an important role in species identification and phylogenetic analysis. However, the only published </span>&l... <span style="font-family:Verdana;">The sequence of the ribosomal RNA gene (rDNA) plays an important role in species identification and phylogenetic analysis. However, the only published </span><span><span style="font-family:Verdana;">full-length sequence of a ribosomal gene of green algae is that of </span><i><span style="font-family:Verdana;">Ulva mutabilis</span></i><span style="font-family:Verdana;">.</span></span><span style="font-family:Verdana;"> In this study, we </span><a name="_Hlk17805857"></a><span style="font-family:Verdana;">amplified the full-length sequence of each ribosomal gene unit of the ribosomal gene of </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;">. The full-length sequence of the ribosomal gene in </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;"> is 8676 bp, including the 1759 bp 18S rDNA, 576 bp internal transcribed spacer (ITS) + 5.8S rDNA, 3282 bp 28S </span><span style="font-family:Verdana;">rDNA, and 3059 bp intergenic spacer (IGS) region. We then carried out a series</span><span style="font-family:Verdana;"> of genetic analyses based on the ITS and IGS sequences, to verify whether IGS </span><span><span style="font-family:Verdana;">sequences are useful for studying the genetic diversity of green algae from different locations. We amplified the IGS sequences of </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;"> from 10 different locations in the Yellow Sea. Multiple alignments of the IGS sequences </span></span><span style="font-family:Verdana;">of samples from these 10 different sites revealed varying degrees of base </span><span><span style="font-family:Verdana;">differences, and comparative analysis of the ITS sequences revealed that our amplified species was classified as </span><i><span style="font-family:Verdana;">Blidingia minima</span></i><span style="font-family:Verdana;"> and distinct from other green a 展开更多
关键词 Blidingia minima RDNA IGS (Intergenic Spacer) Intraspecies Relationships
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Mechanism of size effects of a filler on the wear behavior of ultrahigh molecular weight polyethylene 认领
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作者 Huan Zhang Shicheng Zhao +4 位作者 Zhong Xin Chunlin Ye Zhi Li Jincheng Xia Jiaorong Li 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2020年第7期1950-1963,共14页
Although the size effects of a filler are closely related to the complex multi-level structures of their polymer composites;unfortunately,such relationships remain poorly understood.In this study,we investigated the e... Although the size effects of a filler are closely related to the complex multi-level structures of their polymer composites;unfortunately,such relationships remain poorly understood.In this study,we investigated the effects of various sizes(40-600 nm)of silicon carbide(SiC)fillers on the wear behavior of ultrahigh molecular weight polyethylene(UHMWPE)in the presence of the silane coupling agent KH-560.All of these SiC fillers improved the wear resistance of UHMWPE significantly,with a medium size(150 nm)being optimal.To examine the reasons for this behavior,we analyzed the multi-level structures of the samples in terms of their matrix structures(crystalline;amorphous;interphase),matrix-filler interactions(physical adsorption;chemical crosslinking;hybrid network)and the external effects of SiC fillers(bearing loads;transferring frictional heat).The high rigidity and thermal conductivity of SiC fillers and,more importantly,the intrinsic characteristics of the matrix structures(larger crystal grains;higher interphase;stronger amorphous entangled networks)were the key parameters affecting the enhancement in the wear-resistance of the UHMWPE.Herein,we also provide interpretations of the corresponding physical effects.Our results should improve our understanding of the structure-property relationships and,thus,should guide the formula design of UHMWPE composites. 展开更多
关键词 Ultrahigh molecular weight POLYETHYLENE Wear behavior Structure-property relationships Particle size Silicon carbide Polymer-filler interactions
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Information for Authors 认领
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《动物分类学报:英文版》 CSCD 2020年第1期71-72,共2页
The current journal is mainly focused in zoological systematics.According to Systematics Agenda 2000(1994),systematics is the science built on the following tasks:Taxonomy-the science of discovering,describing,and cla... The current journal is mainly focused in zoological systematics.According to Systematics Agenda 2000(1994),systematics is the science built on the following tasks:Taxonomy-the science of discovering,describing,and classifying species or groups of species(together termed taxa);Phylogenetic analysis-the discovery of the evolutionary relationships among a group of species;and Classification-the grouping of species,ultimately on the basis of evolutionary relationships. 展开更多
关键词 relationships. classify describing
True cicadas (Cicadidae) as prey for the birds of the Western Palearctic: a review 认领
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作者 Pere Pons 《鸟类学研究:英文版》 CSCD 2020年第2期174-182,共9页
Background:True cicadas(Cicadidae)are large and temporarily abundant insects.Their availability may produce demographic and behavioural effects on bird populations,as happens with forest avifauna feeding on periodical... Background:True cicadas(Cicadidae)are large and temporarily abundant insects.Their availability may produce demographic and behavioural effects on bird populations,as happens with forest avifauna feeding on periodical cicadas in North America.In Europe,the Near East and North Africa,knowledge of cicada predation by birds is sparse.Methods:To help fill this gap,I consulted Cramp’s Birds of the Western Palearctic,conducted a search of online databases and used search engines to generate a database of Western Palearctic birds known to eat cicadas.Results:A total of 105 species(16%of those occurring in the region)belonging to 13 orders,and comprising 20 of the 33 passerine families,were found to consume cicadas.I estimated that 69 of these bird species are known to consume cicadas within the limits of the Western Palearctic.Many terrestrial birds predate on cicadas,preferably on adults.Avian predators include cuckoos,owls,bee-eaters,woodpeckers,falcons,reed-warblers,larks,crows and jays,buntings,shrikes,pipits and wagtails,flycatchers and chats,tits,sparrows,leaf-warblers,starlings,warblers and thrushes,but also terns and gulls.Nymphs are consumed by some passerines,owls and herons.Cicadas can make up as much as 70%of food items delivered to nestlings.Analysis of stomach contents and neck collar samples are the most common methods used in diet studies.Conclusions:Available knowledge is biased towards species that have been more intensively studied,and often lack proper quantification of prey items.More studies about the relative importance of cicadas as prey for birds in the Western Palearctic are needed.I suggest using non-invasive studies based on pellets and droppings and prioritizing declining bird species. 展开更多
关键词 Bird species CICADIDAE Cramp’s handbook Diet studies Predator-prey relationships
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环境监测与环境监察的关系及协作运行 认领
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作者 李媛媛 《环境与发展》 2020年第6期179-179,181,共2页
本文对环境保护工作中环境监测和环境监察进行了深入研究,概述了二者的工作职能,总结出了二者之间的关系及现状,并结合相关知识就如何促进二者协作运行提出了具体建议。
关键词 环境监测 环境监察 关系 协作运行
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