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Study on Path Selection and Implementation Effect of Counselors in College Students’Career Planning Education
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作者 Fang Guo Shujun Luo Weihan Li 《Journal of Contemporary Educational Research》 2024年第5期59-64,共6页
Under the background of a severe job market and fierce talent competition,the career planning education of college students is of great importance.In this study,a combination of quantitative and qualitative research m... Under the background of a severe job market and fierce talent competition,the career planning education of college students is of great importance.In this study,a combination of quantitative and qualitative research methods was used;500 students in Shenzhen Polytechnic of Information Technology were surveyed by questionnaire,and 40 counselors were interviewed in depth to comprehensively analyze the role and practical effect of counselors in career planning education.The research showed that the role positioning of counselors includes the guide of students’career development,emotional support,and job-hunting strategy,and the specific path selection involves the strengthening of professional knowledge,the construction of interpersonal relationship networks,and personalized counseling.Based on the survey and interview data,this paper constructed a model for enhancing the role of counselors in career planning education and put forward a set of targeted work paths. 展开更多
关键词 College counselors Career planning Role positioning Path selection Implementation effect
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A Selective‑Response Hypersensitive Bio‑Inspired Strain Sensor Enabled by Hysteresis Effect and Parallel Through‑Slits Structures
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作者 Qun Wang Zhongwen Yao +8 位作者 Changchao Zhang Honglie Song Hanliang Ding Bo Li Shichao Niu Xinguan Huang Chuanhai Chen Zhiwu Han Luquan Ren 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期139-153,共15页
Flexible strain sensors are promising in sensing minuscule mechanical signals,and thereby widely used in various advanced fields.However,the effective integration of hypersensitivity and highly selective response into... Flexible strain sensors are promising in sensing minuscule mechanical signals,and thereby widely used in various advanced fields.However,the effective integration of hypersensitivity and highly selective response into one flexible strain sensor remains a huge challenge.Herein,inspired by the hysteresis strategy of the scorpion slit receptor,a bio-inspired flexible strain sensor(BFSS)with parallel through-slit arrays is designed and fabricated.Specifically,BFSS consists of conductive monolayer graphene and viscoelastic styrene–isoprene–styrene block copolymer.Under the synergistic effect of the bio-inspired slit structures and flexible viscoelastic materials,BFSS can achieve both hypersensitivity and highly selective frequency response.Remarkably,the BFSS exhibits a high gage factor of 657.36,and a precise identification of vibration frequencies at a resolution of 0.2 Hz through undergoing different morphological changes to high-frequency vibration and low-frequency vibration.Moreover,the BFSS possesses a wide frequency detection range(103 Hz)and stable durability(1000 cycles).It can sense and recognize vibration signals with different characteristics,including the frequency,amplitude,and waveform.This work,which turns the hysteresis effect into a"treasure,"can provide new design ideas for sensors for potential applications including human–computer interaction and health monitoring of mechanical equipment. 展开更多
关键词 Bio-inspired strain sensors Hysteresis effect HYPERSENSITIVITY selective frequency response Health monitoring applications
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Enhancing selectivity in acidic CO_(2) electrolysis:Cation effects and catalyst innovation
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作者 Zichao Huang Tinghui Yang +4 位作者 Yingbing Zhang Chaoqun Guan Wenke Gui Min Kuang Jianping Yang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期61-80,共20页
The electrochemical reduction of CO_(2)(eCO_(2)R)under ambient conditions is crucial for reducing carbon emissions and achieving carbon neutrality.Despite progress with alkaline and neutral electrolytes,their efficien... The electrochemical reduction of CO_(2)(eCO_(2)R)under ambient conditions is crucial for reducing carbon emissions and achieving carbon neutrality.Despite progress with alkaline and neutral electrolytes,their efficiency is limited by(bi)carbonates formation.Acidic media have emerged as a solution,addressing the(bi)carbonates challenge but introducing the issue of the hydrogen evolu-tion reaction(HER),which reduces CO_(2) conversion efficiency in acidic environments.This review focuses on enhancing the selectivity of acidic CO_(2) electrolysis.It commences with an overview of the latest advancements in acidic CO_(2) electrolysis,focusing on product selectivity and electrocatalytic activity enhancements.It then delves into the critical factors shaping selectivity in acidic CO_(2) electrolysis,with a special emphasis on the influence of cations and catalyst design.Finally,the research challenges and personal perspectives of acidic CO_(2) electrolysis are suggested. 展开更多
关键词 ACIDIC CO_(2) electrolysis High selectivity Cation effects Catalyst design Competitive HER
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China's Low Export Markups Puzzle: Competition Effect and Selection Effect
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作者 Xu Ming 《China Economist》 2019年第3期98-113,共16页
Based on China's industrial enterprises-customs matched data, this paper utilizes two-tier stochastic frontier analysis method to estimate and verify the extent to which selection effect and competition effect inf... Based on China's industrial enterprises-customs matched data, this paper utilizes two-tier stochastic frontier analysis method to estimate and verify the extent to which selection effect and competition effect influence exporting firms' markup. Our findings suggest that the interaction between selection effect and competition effect ultimately causes actual firm markup to be higher than the baseline markup by 7.11%. Exporting firms' actual markup is higher than the baseline markup by different degrees. In terms of the decomposition of selection effect, TFP explains for 28.05% of selection effect, and nonproductivity factors explain for the rest 71.95%. By controlling for the type of firms' export,the export-productivity paradox only exists for processing trade firms, which shows that with increasing trade facilitation, the policy incentives to encourage firms to export are major contributors to the low export markups. 展开更多
关键词 LOW EXPORT MARKUPS PUZZLE COMPETITION effect selection effect two-tier stochastic frontier analysis
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Automatic Variable Selection for Single-Index Random Effects Models with Longitudinal Data
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作者 Suigen Yang Liugen Xue 《Open Journal of Statistics》 2014年第3期230-237,共8页
We consider the problem of variable selection for the single-index random effects models with longitudinal data. An automatic variable selection procedure is developed using smooth-threshold. The proposed method share... We consider the problem of variable selection for the single-index random effects models with longitudinal data. An automatic variable selection procedure is developed using smooth-threshold. The proposed method shares some of the desired features of existing variable selection methods: the resulting estimator enjoys the oracle property;the proposed procedure avoids the convex optimization problem and is flexible and easy to implement. Moreover, we use the penalized weighted deviance criterion for a data-driven choice of the tuning parameters. Simulation studies are carried out to assess the performance of our method, and a real dataset is analyzed for further illustration. 展开更多
关键词 VARIABLE selection Single-Index MODEL RANDOM effects Longitudinal DATA
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Effect of Two Phase Mixtures on the Selection of the Discharge Path 被引量:1
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作者 DENG He-ming HE Zheng-hao WANG Lei LI Jin 《高电压技术》 EI CAS CSCD 北大核心 2008年第12期2681-2686,共6页
This paper investigates the development,the breakdown process,and the discharge path selection of the lightning discharges in two-phase mixtures(TPMs).13 kinds of solid-gas mixtures and 3 kinds of liquid-gas mixtures ... This paper investigates the development,the breakdown process,and the discharge path selection of the lightning discharges in two-phase mixtures(TPMs).13 kinds of solid-gas mixtures and 3 kinds of liquid-gas mixtures are employed to study effect of two phase mixtures on the selection of the discharge path under lightning impulses.Grain size effects are shown upon these experimental results.When the diameter of solid or liquid grains is less than about 10 μm,the discharge path does not select TPM but air.And the discharge path selects TPM when the diameter is greater than about 100 μm.And when the diameter is between about 10 μm and 100 μm,the discharge path selects TPM under negative lightning impulses,but it has a greater selection of air than TPMs under positive lightning impulses.Volume fraction and permittivity of solid/liquid can also influence the selection of the discharge path. 展开更多
关键词 混合两相体 放电路径 选择 粒度效应 容积率 介电常数
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Expanded models of the project portfolio selection problem with learning effect
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作者 Li Wang Xingmei Li +1 位作者 Lu Zhao Zailing Liu 《CAAI Transactions on Intelligence Technology》 2019年第3期142-147,共6页
This research develops two new models for project portfolio selection, in which the candidate projects are composed of multiple repetitive units. To reflect some real situations, the learning effect is considered in t... This research develops two new models for project portfolio selection, in which the candidate projects are composed of multiple repetitive units. To reflect some real situations, the learning effect is considered in the project portfolio selection problem for the first time. The mathematical representations of the relationship between learning experience and investment cost are provided. One numerical example under different scenarios is demonstrated and the impact of considering learning effect is then discussed. 展开更多
关键词 Expanded MODELS the PROJECT PORTFOLIO selection PROBLEM LEARNING effect
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Neighbour Peer Selection Scheme Based on Effective Capacity for Mobile Peer-to-Peer Streaming
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作者 夏海轮 王宁 曾志民 《China Communications》 SCIE CSCD 2013年第5期89-98,共10页
For Peer-to-Peer (P2P) streaming services in mobile networks, the selection of appropriate neighbour peers from candidate peers with demanding data is an important approach to improve Quality-of-Service (QoS). This pa... For Peer-to-Peer (P2P) streaming services in mobile networks, the selection of appropriate neighbour peers from candidate peers with demanding data is an important approach to improve Quality-of-Service (QoS). This paper proposes a novel Effective Capacity Peer Selection (ECPS) scheme based on effective capacity. In the ECPS scheme, the neighbour peer selection problem was modeled using the Multiple Attribute Decision Making (MADM) theory, which considered multiple factors of candidate peers, including Signal to Interference and Noise Ratio (SINR), residency time, power level, security, moving speed, and effective capacity. This model could increase the suitability of ECPS for wireless mobile environments. Then, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was used to solve the MADM problem and identify the preferred neighbour peers. Simulation results show that the ECPS scheme can improve the network throughput, reduce packet delay by about 82%, and almost double the packet delivery ratio of the mobile P2P streaming service. 展开更多
关键词 P2P mobile P2P streaming peer selection effective capacity MADM QoS
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Selection Effects of Soil Fertility on the Progenies of Soybean Crosses
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作者 Zou Jijun, Yang Qingkai, Wang Jiming(Northeast Agricultural University, Harbin 150030, PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1996年第2期88-93,共6页
The F2, F3, families and F4 lines of six soybean crosses, were selected successively under high-and low - fertility sites with the relection objective of high yield and the method of pedigree was used. Two best F4 - d... The F2, F3, families and F4 lines of six soybean crosses, were selected successively under high-and low - fertility sites with the relection objective of high yield and the method of pedigree was used. Two best F4 - derived lines were chosen from each of the six crosses under both high-and low-fertility for use in this study. In 1995, the total 24 lines were tested in high, medium and low fertility sites with the same experimental design (CRB) to study the selcctoin effects of high and low - fertility. The results suggested that high- and low-fertility had different selection effects. High fertility was more effective for selecting lines, which had higher yield under high-fertility and lower yield under low-fertility; low-fertility was better for selecting lines, which had higher yield under low-fertility and lower yield under low-fertility, and high fertility was somewhat better than low fertility for selecting lines, which had higher yield under both high and low-fertility. It revealed that the lines selected from high-fertility had superior yield potential. The lines selected from high-fertility had shorter plant height, more nodes on main stem, fewer branches, higher seed-stem ratio. The reverse was true for the lines selected from low-fertility . The lodging-resistance of the lines selected from highfertility was greater than that of the lines from low-fertility. The soil fertility level of breeding nursery should be chosen according to the breeding objective. 展开更多
关键词 progenics or soybean crosses soil fertility selection effects
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Pun's Effectiveness and Selectivity in English Advertisements 被引量:1
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作者 王爽 《英语广场(学术研究)》 2011年第Z4期73-76,共4页
This paper lays particular emphasis on pun's effectiveness and selectivity in English advertisements.The illustration and examples can help us understand the English advertisements well and foster our ability to a... This paper lays particular emphasis on pun's effectiveness and selectivity in English advertisements.The illustration and examples can help us understand the English advertisements well and foster our ability to appreciate the charm of English. 展开更多
关键词 ENGLISH ADVERTISEMENTS PUN effectIVENESS selectIVITY
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Selectivity and sublethal effects of some frequently-used biopesticides on the predator Cyrtorhinus lividipennis Reuter(Hemiptera: Miridae) 被引量:2
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作者 DAI Wei LI Yao +3 位作者 ZHU Jun GE Lin-quan YANG Guo-qing LIU Fang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第1期124-133,共10页
The green miridbug,Cyrtorhinus lividipennis,is an important predator of the rice brown planthopper,Nilaparvata lugens.In this study,the selective toxicity of seven commercial biopesticides for C.lividipennis was exami... The green miridbug,Cyrtorhinus lividipennis,is an important predator of the rice brown planthopper,Nilaparvata lugens.In this study,the selective toxicity of seven commercial biopesticides for C.lividipennis was examined under laboratory conditions; abamectin was the most selective to C.lividipennis,followed by matrine and azadirachtin.Veratridine,rotenone,Bacillus thuringiensis and Beauveria bassiana showed less selectivity for C.lividipennis.Subsequently,matrine,abamectin and azadirachtin were selected for sublethal assessments with respect to C.lividipennis due to their high toxicities to N.lugens.C.lividipennis treated with sublethal concentrations(LC10 and LC20) of the three biopesticides could distinguish volatiles released from healthy and N.lugens-infested plants indicating that the biopesticides tested did not affect the foraging ability of surviving miridbugs.Azadirachtin decreased the consumption capability of C.lividipennis when the densities of N.lugens were 20,30,40 and 50 insects per vial.Sublethal concentration treatment did not impact the pre-oviposition period or egg hatchability of C.lividipennis.However,the fecundity of C.lividipennis exposed to azadirachtin and abamectin increased by 27–41% compared to the untreated individuals.In summary,abamectin or matrine together with C.lividipennis could be considered an effective,sustainable pest management strategy for rice. 展开更多
关键词 BIOPESTICIDES Cyrtorhinus lividipennis selective toxicity SUBLETHAL effects
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Layered double hydroxide-like Mg_3Al_(1–x)Fe_x materials as supports for Ir catalysts: Promotional effects of Fe doping in selective hydrogenation of cinnamaldehyde 被引量:4
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作者 Weiwei Lin Haiyang Cheng +3 位作者 Xiaoru Li Chao Zhang Fengyu Zhao Masahiko Arai 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第5期988-996,共9页
Supported Ir catalysts were prepared using layered double hydrotalcite‐like materials,such as Mg3Al1-xFex,containing Fe and Al species in varying amounts as supports.These Ir catalysts were applied for the selective ... Supported Ir catalysts were prepared using layered double hydrotalcite‐like materials,such as Mg3Al1-xFex,containing Fe and Al species in varying amounts as supports.These Ir catalysts were applied for the selective hydrogenation of cinnamaldehyde(CAL).When x was changed from 0(Ir/Mg3Al)to 1(Ir/Mg3Fe),the rate of CAL hydrogenation reached a maximum at approximately x=0.25,while the selectivity to unsaturated alcohol,i.e.,cinnamyl alcohol,monotonously increased from 44.9%to 80.3%.Meanwhile,the size of the supported Ir particles did not change significantly with x,remaining at 1.7-0.2 nm,as determined by transmission electron microscopy.The chemical state of Ir and Fe species in the Ir/Mg3Al1-xFex catalysts was examined by temperature programmed reduction by H2 and X‐ray photoelectron spectroscopy.The surface of the supported Ir particles was also examined through the in‐situ diffuse reflectance infrared Fourier‐transform of a probe molecule of CO.On the basis of these characterization results,the effects of Fe doping to Mg3Al on the structural and catalytic properties of Ir particles in selective CAL hydrogenation were discussed.The significant factors are the electron transfer from Fe2+in the Mg3Al1–xFex support to the dispersed Ir particles and the surface geometry. 展开更多
关键词 Ir catalyst Layered double hydroxide Fe doping Support effect selective hydrogenation CINNAMALDEHYDE
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Genetic Variation Assessed with Microsatellites in Mass Selection Lines of the Pacific Oyster (Crassostrea gigas) in China 被引量:2
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作者 WANG Xubo LI Qi +1 位作者 YU Hong KONG Lingfeng 《Journal of Ocean University of China》 SCIE CAS 2016年第6期1039-1045,共7页
Abstract Four successive mass selection lines of the Pacific oyster, Crassostrea gigas, selected for faster growth in breeding pro- grams in China were examined at ten polymorphic microsatellite loci to assess the lev... Abstract Four successive mass selection lines of the Pacific oyster, Crassostrea gigas, selected for faster growth in breeding pro- grams in China were examined at ten polymorphic microsatellite loci to assess the level of allelic diversity and estimate the effective population size. These data were compared with those of their base population. The results showed that the genetic variation of the four generations were maintained at high levels with an average allelic richness of 18.8-20.6, and a mean expected heterozygosity of 0.902-0.921. They were not reduced compared with those of their base population. Estimated effective population sizes based on temporal variances in microsatellite frequencies were smaller to that of sex ratio-corrected broodstock count estimates. Using a rela- tively large number ofbroodstock and keeping an equal sex ratio in the broodstock each generation may have contributed to retaining the original genetic diversity and maintaining relatively large effective population size. The results obtained in this study showed that the genetic variation was not affected greatly by mass selection progress and high genetic variation still existed in the mass selection lines, suggesting that there is still potential for increasing the gains in future generations of C. gigas. The present study provided im- portant information for future genetic improvement by selective breeding, and for the design of suitable management guidelines for genetic breeding of C. gigas. 展开更多
关键词 Pacific oyster genetic variation MICROSATELLITE mass selection line effective population size
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Family selection and evaluation of Larix gmelinii var.principis-rupprechtii(Mayr.)Pilger based on stem analysis data at multiple sites 被引量:1
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作者 Conghui Zheng Jianfeng Dai +3 位作者 Hongjing Zhang Yuzhong Wang Zhenhua Xu Zichun Du 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1627-1638,共12页
Larix gmelinii var.principis-rupprechtii(Mayr.)Pilger is an important native tree species in North China with advantages of fast growth,straight trunk,and good wood properties.The multi-year and multi-site breeding re... Larix gmelinii var.principis-rupprechtii(Mayr.)Pilger is an important native tree species in North China with advantages of fast growth,straight trunk,and good wood properties.The multi-year and multi-site breeding research of families of the species has not been reported previously.Based on diameter at breast height(DBH),height and volume of 25 families on four experimental sites,we calculated variance components,genetic parameters,juvenile and mature trait correlations and made genotype main effect plus genotype×environment interaction effect(GGE)biplot based on the breeding values estimated using the method of best linear unbiased prediction(BLUP).Compared with height,DBH and volume had higher heritability and larger variation coefficients,making them the more suitable traits for family selection and evaluation.Based on these,GGE biplots containing 20 combinations of site×age were drawn using data at 13 to 17 years when the interactions between family and location were strong.Test sites classifications based on DBH,and volume were inconsistent,with two categories for DBH and one for volume.The Guyuan site was the most suitable with strong discriminating ability,high representativeness and stability among tree ages.Integrating the ranking results of DBH and volume,families 66,76,82 and 111 were high-yielding and stable,families 78 and96 were high-yielding with above average stability,families72 and 79 were high-yielding with below average stability,whereas stability of family 100 was inconsistent between DBH and volume.Early selection based on DBH was convenient and reliable,and can be made at seven years.This study provides support for the selection of Larix gmelinii var.principis-rupprechtii families in Hebei province and an example for the application of stem analysis data from multiple sites in tree breeding. 展开更多
关键词 Larix gmelinii var principis-rupprechtii Stem analysis MULTI-SITE Early selection Genotype main effect plus Genotype-environmental interaction effect(GGE)biplot
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An Improved Elastic Net for Cancer Classification and Gene Selection 被引量:7
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作者 LI Jun-Tao JIA Ying-Min 《自动化学报》 EI CSCD 北大核心 2010年第7期976-981,共6页
关键词 癌症 弹性网络 基因组 计算方法
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Immunomodulatory effects of selected Malaysian plants on the CD18/11a expression and phagocytosis activities of leukocytes
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作者 Nurul Hikmah Harun Abdi Wira Septama Ibrahim Jantan 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第1期48-53,共6页
Objective:To investigate the effects of 20 methanolic extracts from Malaysian selected plants on CD18/11 a expression and phagocytosis activity of leukocytes using flow cytometry analysis.Methods:The effects of methan... Objective:To investigate the effects of 20 methanolic extracts from Malaysian selected plants on CD18/11 a expression and phagocytosis activity of leukocytes using flow cytometry analysis.Methods:The effects of methanolic extracts on CD18/11 a expression and phagocytosis of leukocytes were measured by labelling the cells with CD18-fluorescein isolhiocyanaie and ingestion labelled with Escherichia coli-fluorescein isothiocyanate and then analyzed using flow cytometer.Results:About 12 out of 20 methanolic extracts of selected Malaysian medicinal plants significantly(P≤0.05) inhibited the CD18/1 la expression of leukocytes at both concentrations of 6.25 μg/mL and 100 μg/mL in dose dependent manner.The most active inhibitory was shown in Citrus aurantifolia(Christm.) Swingle and Alpinia galangal(L.) Willd.at dosage 100ug/mL.Moreover,the Orthosiphon aristatus(Blume) Miq(O.aristatus).showed the highest stimulatory activity at the concentration of 100 μg/mL.Other than that,four plant extracts significantly(P<0.05) rose the phagocytosis activities of leukocytes in dose dependent manner.However,Annona muricata L.and O.aristatus showed the highest stimulated activities at the 100 pg/mL concentration.Conclusions:The results suggest that methanolic extracts of Cirrus aurantifolia.Alpinia gaiangal,O.aristatus and Annona muricata are able to modulate innate immune system and can potentially be recognized as therapeutic agents for modulating immune system. 展开更多
关键词 selectED MALAYSIAN medicinal PLANTS Immunomodulatory effects CD18/11a EXPRESSION PHAGOCYTOSIS activity Flow cytometry analysis
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Submicro-battery effect and selective bio-oxidation model of gold-bearing arsenopyrite by Thiobacillus ferrooxidans 被引量:4
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作者 杨洪英 杨立 +3 位作者 赵玉山 陈刚 吕久吉 范有静 《中国有色金属学会会刊:英文版》 CSCD 2002年第6期1199-1202,共4页
Through the study by electronic probe it was found that many new cracks and holes appear on the surface of gold bearing arsenopyrite crystal oxidized by Thiobacillus ferrooxidans, which are along with some directions.... Through the study by electronic probe it was found that many new cracks and holes appear on the surface of gold bearing arsenopyrite crystal oxidized by Thiobacillus ferrooxidans, which are along with some directions. Then the selective bio oxidation model of gold bearing arsenopyrite was set up. The selective bio oxidation resulting from the submicro battery effect of gold/ arsenopyrite mineral pairs naturally forms in the gold bearing arsenopyrite crystal. Thiobacillus ferrooxidans has priority to oxidize the place of gold rich and oxidizes selectedly along with the crystal border, crystal face and crack. The bacteria oxidation process of gold bearing arsenopyrite is divided into three stages: the first stage is the surface oxidation, the second stage is restraining oxidation and the third stage is the filament oxidation, bacteria oxidize along with cracks of arsenopyrite. 展开更多
关键词 选择性生物氧化模型 亚微米电池效应 砷黄铁矿 铁氧化剂
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Comparison, Selection and Progeny Test of Natural Populations of White Birch (Betula platyphylla Suk.) in Northern China
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作者 Shibo LAN 《Agricultural Biotechnology》 CAS 2019年第4期113-118,共6页
[Objectives]This study was conducted to rationally and effectively use natural genetic resources of white birch(Betula platyphylla Suk.),and improve the scientific and technological content of improved varieties.[Meth... [Objectives]This study was conducted to rationally and effectively use natural genetic resources of white birch(Betula platyphylla Suk.),and improve the scientific and technological content of improved varieties.[Methods]With the progeny of the white birch populations naturally distributed in northern China as objects,based on genetic effect analysis and comprehensive evaluation,the genetic variation,heritability and genetic gain of the growth characters in the progeny forest were systematically analyzed,by which populations or individuals with good growth vigor and strong stress resistance and adaptability were finally selected.[Results]There were extremely significant differences in the growth characters between the natural populations of white birch in northern China.The variation was the smallest in tree height,followed by crown width,and largest in DBH,and the average coefficients of variation were 20.56%,32.25%and 33.00%,respectively.The differences in characters between progeny of the same population were also extremely significant.The growth characters of white birch were more controlled by genes,and the genetic gains were larger.The heritability of tree height,DBH and crown width was 0.971,0.816 and 0.576,respectively,and the genetic gains were 15.97%,21.54%and 13.87%,respectively.[Conclusions]With the growth characters as the main evaluation indexes,taking various influencing factors into account,the Shanxi[SX]population,Hebei[HB]population and Liaoning[LN]population were selected to be excellent populations,and LN305,SX516 and HB403 were excellent individuals,which are advised to be widely used in multi-generation genetic improvement breeding. 展开更多
关键词 BETULA platyphylla Suk. Natural population COMPARISON and selection PROGENY test GENETIC effect GENETIC gain
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Mice selected for large and small brain weight: The preservation of trait differences after the selection was discontinued
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作者 Olga V. Perepelkina Vassilissa A. Golibrodo +1 位作者 Irina G. Lilp Inga I. Poletaeva 《Advances in Bioscience and Biotechnology》 2013年第6期1-8,共8页
The selection for large and small relative brain weight (RBW) in mice, started in 1999, resulted in stable significant differences in the trait (16%). The selection was discontinued at F22, and both lines (Large Brain... The selection for large and small relative brain weight (RBW) in mice, started in 1999, resulted in stable significant differences in the trait (16%). The selection was discontinued at F22, and both lines (Large Brain, LB and Small brain, SB) were maintained by random mating. In F25-F28 the significant differences in RBW were still present in spite of the lack of selection. In F28 ethanol injections (2.4 mg/kg, 12% ethanol, i.p.) were performed to animals of both lines. The ethanol effects were more intense in SB, than in LB line. Mice were tested in elevated and closed plus-mazes and in slip-funnel tests. Control LB mice explored new environment more actively and were less affected by stressful environment than SBs. SB ethanol mice were less anxious in elevated plus maze, initiated closed maze exploration earlier, moved more vividly and demonstrated lower anxiety level in elevated plus maze than saline injected mice, while changes in these behaviors after ethanol were not so clear in LB mice, although their locomotion level increased. 展开更多
关键词 selection Brain Weight ETHANOL effects ANXIETY Exploration Cross Mazes
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Selective Synthesis of Different-Sized Gold Nanoclusters through HCI-Etching and-Growth Effect
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作者 Ting Huang Zhi-hu Sun Guo-qiang Pan 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第2期223-228,246,共7页
Controllable syntheses of different-sized gold nanoclusters are of great significance for their fundamental science and practical applications. In this work, we achieve the controllable and selective syntheses of Au7 ... Controllable syntheses of different-sized gold nanoclusters are of great significance for their fundamental science and practical applications. In this work, we achieve the controllable and selective syntheses of Au7 and Au13 clusters through adding HCl to the traditional Aull synthetic route at different reaction time. Time-dependent mass spectra and UV- Vis spectra were ernployed to monitor these two HCl-directed processes, and revealed the distinct roles of HCl as an etchant or a growth prornotor, respectively. Furthermore, parallel experiments on independent synthetic routes involving only non-chlorine H+ (acetic acid) or Cl (tetraethy larnrnoniurn chloride) instead of HCl were perforrned, which illustrated the main role of H^+-etching and Cl^ -assisted growth in HCl-directed cluster synthetic routes. We propose the HCl-etching is mainly achieved via the H+ action to break the Au(I)-PPh3 part of clusters, while the HCl-prornoted growth is realized via the attachment of Au-Cl species to the pre-forrned clusters. 展开更多
关键词 selective synthesis Route control HC1 Etching and growth effects
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