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Exploring the Effects of Gap-Penalties in Sequence-Alignment Approach to Polymorphic Virus Detection 被引量:1
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作者 Vijay Naidu Jacqueline Whalley Ajit Narayanan 《Journal of Information Security》 2017年第4期296-327,共32页
Antiviral software systems (AVSs) have problems in identifying polymorphic variants of viruses without explicit signatures for such variants. Alignment-based techniques from bioinformatics may provide a novel way to g... Antiviral software systems (AVSs) have problems in identifying polymorphic variants of viruses without explicit signatures for such variants. Alignment-based techniques from bioinformatics may provide a novel way to generate signatures from consensuses found in polymorphic variant code. We demonstrate how multiple sequence alignment supplemented with gap penalties leads to viral code signatures that generalize successfully to previously known polymorphic variants of JS. Cassandra virus and previously unknown polymorphic variants of W32.CTX/W32.Cholera and W32.Kitti viruses. The implications are that future smart AVSs may be able to generate effective signatures automatically from actual viral code by varying gap penalties to cover for both known and unknown polymorphic variants. 展开更多
关键词 POLYMORPHIC Malware Variants gap Penalties Syntactic Approach Pairwise SEQUENCE ALIGNMENT Multiple SEQUENCE ALIGNMENT Automatic Signature Generation Smith-Waterman Algorithm JS. Cassandra VIRUS W32.CTX/W32.Cholera VIRUS W32.Kitti VIRUS
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Closing the Gap: Boosting Women’s Representation in Cybersecurity Leadership
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作者 Yasser Asiry 《Journal of Information Security》 2024年第1期15-23,共9页
The research consistently highlights the gender disparity in cybersecurity leadership roles, necessitating targeted interventions. Biased recruitment practices, limited STEM education opportunities for girls, and work... The research consistently highlights the gender disparity in cybersecurity leadership roles, necessitating targeted interventions. Biased recruitment practices, limited STEM education opportunities for girls, and workplace culture contribute to this gap. Proposed solutions include addressing biased recruitment through gender-neutral language and blind processes, promoting STEM education for girls to increase qualified female candidates, and fostering inclusive workplace cultures with mentorship and sponsorship programs. Gender parity is crucial for the industry’s success, as embracing diversity enables the cybersecurity sector to leverage various perspectives, drive innovation, and effectively combat cyber threats. Achieving this balance is not just about fairness but also a strategic imperative. By embracing concerted efforts towards gender parity, we can create a more resilient and impactful cybersecurity landscape, benefiting industry and society. 展开更多
关键词 CYBERSECURITY Workforce LEADERSHIP GENDER gap Women REPRESENTATION
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The Gap Labelling Integrated Density of States for a Quasi Crystal Universe Is Identical to the Observed 4.5 Percent Ordinary Energy Density of the Cosmos 被引量:2
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作者 Mohamed S. El Naschie 《Natural Science》 2014年第16期1259-1265,共7页
Condense matter methods and mathematical models used in solving problems in solid state physics are transformed to high energy quantum cosmology in order to estimate the magnitude of the missing dark energy of the uni... Condense matter methods and mathematical models used in solving problems in solid state physics are transformed to high energy quantum cosmology in order to estimate the magnitude of the missing dark energy of the universe. Looking at the problem from this novel viewpoint was rewarded by a rather unexpected result, namely that the gap labelling method of integrated density of states for three dimensional icosahedral quasicrystals is identical to the previously measured and theoretically concluded ordinary energy density of the universe, namely a mere 4.5 percent of Einstein’s energy density, i.e. E(O) = mc2/22 where E is the energy, m is the mass and c is the speed of light. Consequently we conclude that the missing dark energy density must be E(D) = 1 - E(O) = mc2(21/22) in agreement with all known cosmological measurements and observations. This result could also be interpreted as a strong evidence for the self similarity of the geometry of spacetime, which is an expression of its basic fractal nature. 展开更多
关键词 E-INFINITY Theory Fractal-Witten M-THEORY gap Labelling Theorem DENSITY of States Dark Energy DENSITY Noncommutative Geometry K-THEORY Dimension Group
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Energy Gap in Saturn’s Rings
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作者 Andrey Yu Pospelov Vladimir V. Tchernyi 《Journal of Modern Physics》 2019年第4期477-485,共9页
In this article, we consider, based on the super-diamagnetic model, the new problems of Saturn’s rings discovered by Cassini, such as: 1) anomalous purity of water ice;2) Saturn’s magnetic field alignment with the p... In this article, we consider, based on the super-diamagnetic model, the new problems of Saturn’s rings discovered by Cassini, such as: 1) anomalous purity of water ice;2) Saturn’s magnetic field alignment with the planet’s rotation axis;3) “ring rain” of the submicron particles;4) the deviation in the qualitative composition of the “rain” from the composition of the rings;5) “dirt” concentrated in the ring gaps;6) “plateaus” in Saturn’s C ring;7) age of the rings;8) roll-off in the spectrum of Saturn’s rings, and 9) “propellers” in Saturn’s A ring. Interpretation of Cassini’s observations of spectral roll-off in Saturn’s rings in the wavelength range from 100 micrometers to 0.5 mm is given. It was concluded that the substance of the rings could be in the superconducting state. An explanation of the Cassini spectral data is given using the hypothesis of the existence of a superconducting energy gap in the substance of rings. 展开更多
关键词 SATURN RINGS CASSINI CIRS Interpretation Super-Diamagnetic Model Superconducting Energy gap Ring RAIN PLATEAUS and PROPELLERS in Saturns RINGS
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Expression of gap junction genes connexin 32,connexin 43 and their proteins in hepatocellular carcinoma and normal liver tissues 被引量:9
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作者 Ma XD Sui YF Wang WL 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第1期66-69,共4页
AIM To investigate the significance andmechanism of cx32 mRNA,cx43 mRNA and theirproteins in hepatocarcinogenesis.METHODS Sixty-one cases of HCC and 14cases of normal liver tissues were detected byimmunohistochemical ... AIM To investigate the significance andmechanism of cx32 mRNA,cx43 mRNA and theirproteins in hepatocarcinogenesis.METHODS Sixty-one cases of HCC and 14cases of normal liver tissues were detected byimmunohistochemical and in situ hybridization(ISH)methods.RESULTS In HCC grades Ⅰ,Ⅱ,Ⅲ and normalliver tissues,the positive rates of Cx32 proteinwere 55.6%,42.1%,18.2% and 92.9%,respectively.The detection rates of Cx43 proteinwere 44.4%,26.3%,12.1% and 78.6%,respectively.There was significant difference inCx32 and Cx43 protein between HCC and normalliver tissues(P【0.01).ISH the positive rates ofcx32 mRNA shown by ISH in HCC grades Ⅰ,Ⅱ,Ⅲ and normal liver tissues were 88.9%,84.2%,87.9% and 92.9%,respectively.Those of cx43mRNA were 77.8%,78.6%,78.8% and 85.7%,respectively.There was no statistical differencein the positive rates of cx32 mRNA and cx43mRNA between HCC and normal liver tissue(P】0.05).CONCLUSION The aberrant location of Cx32and Cx43 proteins could be responsible forprogression of hepatocarcinogenesis,and thedefect of cx genes in post-translationalprocessing might be the possible mechanism. 展开更多
关键词 Subject headings CONNEXIN gap junction liver NEOPLASM IMMUNOHISTOCHEMISTRY in SITU hybridization carcinoma hepatocellular gene EXPRESSION
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烤烟GAP技术现状与展望 被引量:13
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作者 刘芳 李永忠 +1 位作者 文国松 丁金玲 《中国农学通报》 CSCD 2005年第4期322-325,340,共5页
为全面快速提升中国烟叶生产技术和质量管理水平,使中国优质烟叶生产形成规模,在此详细介绍了目前世界发达国家采用的优质农业生产管理模式-GAP,介绍了GAP的概念、在中国烟叶生产中推行GAP的意义和实施措施,以及中国目前推行GAP管理模... 为全面快速提升中国烟叶生产技术和质量管理水平,使中国优质烟叶生产形成规模,在此详细介绍了目前世界发达国家采用的优质农业生产管理模式-GAP,介绍了GAP的概念、在中国烟叶生产中推行GAP的意义和实施措施,以及中国目前推行GAP管理模式的情况。通过分析和考查烤烟GAP的实际应用情况,结合中国国情对其应用和推广提出几点建议。分析认为:(1)中国主要烟区推行GAP技术对从根本上解决中国多年来烟叶生产、管理、收购与质量监督的无序与混乱起到良好效果;(2)IC卡系统与GAP技术的结合对促进烤烟GAP技术的应用与推广有较好的作用;(3)中国推广烟叶农场种植模式与烤烟GAP的应用是相互关联的;(4)生产执行系统(MES)在GAP技术中的应用是可行的:(5)农业信息技术在烤烟GAP管理中的应用是多方面的。 展开更多
关键词 gap技术 IC gap管理
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Evaluation of Energy Band Gap, Thermal Conductivity, Phase Transition Temperature and Elastic Response of PS/CdS Semiconducting Optical Nanocomposite 被引量:1
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作者 Vishal Mathur Kuldeep S. Rathore Kananbala Sharma 《World Journal of Nano Science and Engineering》 2013年第3期93-99,共7页
Thick film of Polystyrene (PS)/CdS semiconducting optical nanocomposite has been synthesized by dispersing nanofiller particles of CdS in PS matrix. The nanostructure of the CdS particles has been ascertained through ... Thick film of Polystyrene (PS)/CdS semiconducting optical nanocomposite has been synthesized by dispersing nanofiller particles of CdS in PS matrix. The nanostructure of the CdS particles has been ascertained through X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). Small angle x-ray scattering analysis has been performed in order to ascertain nanocomposite character of the PS/CdS sample. Scanning Electron Microscopy (SEM) analyses of these samples have been carried out to establish the surface morphology. Optical Absorption Spectroscopy is used to measure the energy band gap of PS/CdS nanocomposite by using Tauc relation whereas Transient Plane Source Technique is used for the determination of thermal conductivity of the prepared samples. The phase transition temperature and elastic response of the prepared samples have been ascertained through Dynamic Mechanical Analyzer (DMA). This study reveals that the thermal conductivity, Young’s modulus and the toughness of the material are greatly influenced by the existence of interfacial energetic interaction between dispersed CdS nanofiller particles and matrix of PS. 展开更多
关键词 Polymer NANOCOMPOSITE SAXS Analysis Energy BAND gap Phase Transition Temperature Thermal Transport Property ELASTIC Properties
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New Nurse Perceptions of Preparedness: Elements of Academic-Practice Gap
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作者 Bonnie Crumley Aybar 《Open Journal of Nursing》 2024年第7期298-320,共23页
The education-practice gap, also known as the academic-practice gap is recognized as the difference between what a nursing student is taught and what the new nurse will experience in practice. This study evaluated spe... The education-practice gap, also known as the academic-practice gap is recognized as the difference between what a nursing student is taught and what the new nurse will experience in practice. This study evaluated specific education outcomes of schools of nursing in New Hampshire through surveys of new nurses and their employers. The responses were explored in relation to identified factors such as curriculum and clinical hours. The findings suggest that the new nurses felt prepared for practice, except in relationship to provision of care and medication administration for six or more patients. Of note is that 61% percent of participants were involved in errors and of these, 37.5% indicated that their education did not prepare them to administer medications to large groups. Evaluation of employer responses points to at least one and sometimes two levels of lower perception of perceived preparedness by the employer. The results highlight the differences between perceptions of preparedness of new nurse and employer, differences in perception of preparedness based on program type for specific gap elements, and the high rate of errors among new nurses. These results underscore the need for further research regarding the education practice gap, error factors, perceptions of preparedness for practice, and practice-readiness expectations of employers. 展开更多
关键词 NURSE Education-gap Education Program PREPAREDNESS COMPETENCY
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Up-Regulation of the Gap Junction Intercellular Communication by Tea Polyphenol in the Human Metastatie Lung Carcinoma Cell Line 被引量:3
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作者 Xiangyong Li Qinghua Wang +6 位作者 Jun Yang Yanjuan Pan Qingyong Chen Xiqing Yan Daxin Wang Xijian Zhou Yuquan Wu 《Journal of Cancer Therapy》 2012年第1期64-70,共7页
Our previous study has proven that tea polyphenol has a role in lung neoplasms. The present communication was to investage the anti-proliferation effect of tea polyphenol on the PG cells, which was a high metastatic h... Our previous study has proven that tea polyphenol has a role in lung neoplasms. The present communication was to investage the anti-proliferation effect of tea polyphenol on the PG cells, which was a high metastatic human lung carcinoma cell line, by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide (MTT) cell viability assay, and to study the change of intracellular calcium concentration, connexin43 (Cx43) expression, gap junctional intercellular communication (GJIC) and cell cycle distribution after the tea polyphenol treatment by laser scanning confocal microscopy and flow cytometry. The results showed that 1) tea polyphenol could kill the PG cells in a dose-depent manner via inhibiting the PG cell proliferation and blocking the PG cell cycle progression staying in G0/G1 phase and not transfering in S and G2/M phases to reduce the PG cell proliferation index;2) the increases of intracellular calcium concentration, GJIC and Cx43 expression were related with the tea polyphenol doses. The data suggested that tea polyphenol could inhibit the growth of PG cells, which mechanism was associated with the up-regulation of GJIC. 展开更多
关键词 Tea POLYPHENOL LUNG Neoplasms Highly METASTATIC HUMAN LUNG Carcinoma Cell Line gap Junction INTERCELLULAR Communication
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Some Implications of an Alternate Equation for the BCS Energy Gap
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作者 Gulshan Prakash Malik Manuel de Llano 《Journal of Modern Physics》 2013年第4期6-12,共7页
A set of generalized-BCS equations (GBCSEs) was recently derived from a temperature-dependent Bethe-Salpeter equation and shown to deal satisfactorily with the experimental data comprising the Tcs and the multiple gap... A set of generalized-BCS equations (GBCSEs) was recently derived from a temperature-dependent Bethe-Salpeter equation and shown to deal satisfactorily with the experimental data comprising the Tcs and the multiple gaps of a variety of high-temperature superconductors (SCs). These equations are formulated in terms of the binding energies W1(T),W2(T),… of Cooper pairs (CPs) bound via one- and more than one-phonon exchange mechanisms;they contain no direct reference to the gap/s of an SC. Applications of these equations so far were based on the observation that for elemental SCs |W01|=△0 at T = 0 inthe limit of the dimensionless BCS interaction parameter λ→0. Here △0 is the zero-temperature gap whence it follows that the binding energy of a CP bound via one-phonon exchanges at T = 0 is 2|W01|. In this note we carry out a detailed comparison between the GBCSE-based W1(T) and the BCS-based energy gap △(T) for all 0≤T≤Tc and realistic, non-vanishingly-small values of λ. Our study is based on the experimental values of Tc Debye temperature , and ?0 of several selected elements including the “bad actors” such as Pb and Hg. It is thus established that the equation for W1(T) provides a viable alternative to the BCS equation for △(T). This suggests the use of, when required, the equation for W2(T) which refers to CPs bound via two-phonon exchanges, for the larger of the two T-dependent gaps of a non-elemental SC. These considerations naturally lead one to the concept of T-dependent interaction parameters in the theory of superconductivity. It is pointed out that such a concept is needed both in the well-known approach of Suhl et al. to multi-gap superconductivity and the approach provided by the GBCSEs. Attention is drawn to diverse fields where T-dependent Hamiltonians have been fruitfully employed in the past. 展开更多
关键词 BCS and Generalized-BCS EQUATIONS T-Dependent EQUATIONS for BCS gap and for Binding Energy of COOPER Pairs ELEMENTAL and Composite SUPERCONDUCTORS
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Development of a particle swarm optimization based support vector regression model for titanium dioxide band gap characterization
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作者 Taoreed O.Owolabi 《Journal of Semiconductors》 EI CAS CSCD 2019年第2期49-55,共7页
Energy band gap of titanium dioxide(TiO_2) semiconductor plays significant roles in many practical applications of the semiconductor and determines its appropriateness in technological and industrial applications such... Energy band gap of titanium dioxide(TiO_2) semiconductor plays significant roles in many practical applications of the semiconductor and determines its appropriateness in technological and industrial applications such as UV absorption, pigment,photo-catalysis, pollution control systems and solar cells among others. Substitution of impurities into crystal lattice structure is the most commonly used method of tuning the band gap of TiO_2 for specific application and eventually leads to lattice distortion. This work utilizes the distortion in the lattice structure to estimate the band gap of doped TiO_2, for the first time, through hybridization of a particle swarm optimization algorithm(PSO) with a support vector regression(SVR) algorithm for developing a PSO-SVR model. The precision and accuracy of the developed PSO-SVR model was further justified by applying the model for estimating the effect of cobalt-sulfur co-doping, nickel-iodine co-doping, tungsten and indium doping on the band gap of TiO_2 and excellent agreement with the experimentally reported values was achieved. Practical implementation of the proposed PSO-SVR model would further widen the applications of the semiconductor and reduce the experimental stress involved in band gap determination of TiO_2. 展开更多
关键词 band gap LATTICE DISTORTION crystal LATTICE parameters particle SWARM optimization support vector regression titanium dioxide
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Bridging larger gaps in peripheral nerves using neural prosthetics and physical therapeutic agents 被引量:1
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作者 Muhammad Sana Ullah Sahar Matthew Barton Geoffrey Douglas Tansley 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第7期1109-1115,共7页
Peripheral nerve injuries are relatively common and can be caused by a variety of traumatic events such as motor vehicle accidents.They can lead to long-term disability,pain,and financial burden,and contribute to poor... Peripheral nerve injuries are relatively common and can be caused by a variety of traumatic events such as motor vehicle accidents.They can lead to long-term disability,pain,and financial burden,and contribute to poor quality of life.In this review,we systematically analyze the contemporary literature on peripheral nerve gap management using nerve prostheses in conjunction with physical therapeutic agents.The use of nerve prostheses to assist nerve regeneration across large gaps(> 30 mm) has revolutionized neural surgery.The materials used for nerve prostheses have been greatly refined,making them suitable for repairing large nerve gaps.However,research on peripheral nerve gap management using nerve prostheses reports inconsistent functional outcomes,especially when prostheses are integrated with physical therapeutic agents,and thus warrants careful investigation.This review explores the effectiveness of nerve prostheses for bridging large nerve gaps and then addresses their use in combination with physical therapeutic agents. 展开更多
关键词 NERVE repair NERVE CONDUITS NERVE PROSTHESIS PHYSICAL therapeutic agents electric stimulation NERVE gap AXONAL growth NERVE regeneration
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Repair of peripheral nerve defects by nerve transposition using small gap bio-sleeve suture with different inner diameters at both ends 被引量:1
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作者 Yu-Hui Kou You-Lai Yu +7 位作者 Ya-Jun Zhang Na Han Xiao-Feng Yin Yu-Song Yuan Fei Yu Dian-Ying Zhang Pei-Xun Zhang Bao-Guo Jiang 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第4期706-712,共7页
During peripheral nerve transposition repair, if the diameter difference between transposed nerves is large or multiple distal nerves must be repaired at the same time, traditional epineurial neurorrhaphy has the prob... During peripheral nerve transposition repair, if the diameter difference between transposed nerves is large or multiple distal nerves must be repaired at the same time, traditional epineurial neurorrhaphy has the problem of high tension at the suture site, which may even lead to the failure of nerve suture. We investigated whether a small gap bio-sleeve suture with different inner diameters at both ends can be used to repair a 2-mm tibial nerve defect by proximal transposition of the common peroneal nerve in rats and compared the results with the repair seen after epineurial neurorrhaphy. Three months after surgery, neurological function, nerve regeneration, and recovery of nerve innervation muscle were assessed using the tibial nerve function index, neuroelectrophysiological testing, muscle biomechanics and wet weight measurement, osmic acid staining, and hematoxylin-eosin staining. There was no obvious inflammatory reaction and neuroma formation in the tibial nerve after repair by the small gap bio-sleeve suture with different inner diameters at both ends. The conduction velocity, muscle strength, wet muscle weight, cross-sectional area of muscle fibers, and the number of new myelinated nerve fibers in the biosleeve suture group were similar to those in the epineurial neurorrhaphy group. Our findings indicate that small gap bio-sleeve suture with different inner diameters at both ends can achieve surgical suture between nerves of different diameters and promote regeneration and functional recovery of injured peripheral nerves. 展开更多
关键词 NERVE REGENERATION bio-sleeve small gap SLEEVE SUTURE NERVE TRANSPOSITION NERVE defect NERVE conduit NERVE reinnervation peripheral NERVE neural REGENERATION
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Object-based forest gaps classification using airborne LiDAR data 被引量:4
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作者 Xuegang Mao Jiyu Hou 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第2期617-627,共11页
Object-based classification differentiates forest gaps from canopies at large regional scale by using remote sensing data. To study the segmentation and classification processes of object-based forest gaps classificat... Object-based classification differentiates forest gaps from canopies at large regional scale by using remote sensing data. To study the segmentation and classification processes of object-based forest gaps classification at a regional scale, we sampled a natural secondary forest in northeast China at Maoershan Experimental Forest Farm.Airborne light detection and ranging(LiDAR; 3.7 points/m2) data were collected as the original data source and the canopy height model(CHM) and topographic dataset were extracted from the LiDAR data. The accuracy of objectbased forest gaps classification depends on previous segmentation. Thus our first step was to define 10 different scale parameters in CHM image segmentation. After image segmentation, the machine learning classification method was used to classify three kinds of object classes, namely,forest gaps, tree canopies, and others. The common support vector machine(SVM) classifier with the radial basis function kernel(RBF) was first adopted to test the effect of classification features(vegetation height features and some typical topographic features) on forest gap classification.Then the different classifiers(KNN, Bayes, decision tree,and SVM with linear kernel) were further adopted to compare the effect of classifiers on machine learning forest gaps classification. Segmentation accuracy and classification accuracy were evaluated by using Mo¨ller's method and confusion metrics, respectively. The scale parameter had a significant effect on object-based forest gap segmentation and classification. Classification accuracies at different scales revealed that there were two optimal scales(10 and 20) that provided similar accuracy, with the scale of 10 yielding slightly greater accuracy than 20. The accuracy of the classification by using combination of height features and SVM classifier with linear kernel was91% at the optimal scale parameter of 10, and it was highest comparing with other classification classifiers, such as SVM RBF(90%), Decision Tree(90%), Bayes(90%),or KNN(87%). The classifiers had no significant effect on forest gap classification, but the fewer parameters in the classifier equation and higher speed of operation probably lead to a higher accuracy of final classifications. Our results confirm that object-based classification can extract forest gaps at a large regional scale with appropriate classification features and classifiers using LiDAR data. We note, however, that final satisfaction of forest gap classification depends on the determination of optimal scale(s) of segmentation. 展开更多
关键词 FOREST gap Scale segmentation Classification FEATURE LIDAR CHM Object based Machine learning
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Contribution of soil fauna to the degradation of recalcitrant components in Cinnamomum camphora foliar litter in different-sized gaps in Pinus massoniana plantations 被引量:2
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作者 Yan Zhang Danju Zhang +1 位作者 Xun Li Jian Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第3期931-941,共11页
Forest gaps are important in forest dynamics and management, but little is known about how soil fauna influence the degradation of recalcitrant litter components in different-sized forest gaps. This investigation uses... Forest gaps are important in forest dynamics and management, but little is known about how soil fauna influence the degradation of recalcitrant litter components in different-sized forest gaps. This investigation uses litterbags with two different mesh sizes (0.04 and 3 mm) to control the meso- and microfauna entering the bags to quantify the contribution of soil fauna to the degradation of recalcitrant components (including condensed tannins, total phenol, lignin and cellulose) during litter decomposition. The experiment was conducted in seven different forest gap sizes in Pinus massoniana plantations over 1 year. One closed-canopy site (CC) and forest gap sizes of 100, 225, 400, 625, 900, 1225 and 1600 m^2 were created in a P. massoniana plantation in the Sichuan basin of China;the CC was treated as the control. Cinnamomum camphora foliage from local native trees was used in all forest gap experiments. We found the following:(1) Gap size had significant effects on the degradation rates (E) of condensed tannins and lignin and on the contributions of soil fauna;medium-sized gaps also presented high degradation rates. Soil fauna obviously contributed to the degradation of recalcitrant foliar litter components in medium-sized gaps.(2) The highest contribution to degradation (40.98%) was recorded for lignin, and the lowest contribution (0.29%) was recorded for condensed tannins. The results indicate that medium-sized gaps (900 m^2) were conducive to the degradation of recalcitrant litter components by soil fauna. 展开更多
关键词 CINNAMOMUM camphora FOLIAR LITTER gap size Pinus massoniana RECALCITRANT LITTER components Soil fauna
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Study on Stack Effect of Stairwell by Numerical Model of Leakage Flow through Gap of Door
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作者 Jung-Yup Kim Ji-Seok Kim 《Open Journal of Fluid Dynamics》 2013年第4期241-247,共7页
Since stack effect that occurs in high-rise buildings has an effect on the indoor environment of the buildings, energy loss and smoke control in case of a fire, there is a need to conduct research on this. For an anal... Since stack effect that occurs in high-rise buildings has an effect on the indoor environment of the buildings, energy loss and smoke control in case of a fire, there is a need to conduct research on this. For an analysis of the stack effect, analysis methods on the leakage flow through gap of interior door shall be formulated. Until now, studies related to the gap leakage flow in buildings have mainly analyzed flow field and pressure in the buildings one-dimensionally using pressure difference-leakage flowrate relations of Orifice Equation and a network numerical analysis algorithm that as- sumes each compartment in the buildings as a single point. In this study, the Momentum Loss Model which enables pressure drop to be proportional to the flow velocity through the gap of door in computational domain of 3-dimensional numerical analysis was proposed to reflect the gap flow phenomenon effectively in 3-dimensional numerical analysis. Using the proposed model, 3-dimensional numerical analysis of the stack effect on the stairs in buildings was performed, and the effects of separation door and lobby between stair and accommodation on the stack effect were investigated. 展开更多
关键词 STACK Effect LEAKAGE Flow gap of DOOR MOMENTUM Loss Model Separation DOOR NUMERICAL Analysis
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Phenotypic changes of Schwann cells on the proximal stump of injured peripheral nerve during repair using small gap conduit tube
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作者 Shi-jun Zhang Wen-liang Wu +2 位作者 Kai-yun Yang Yun-zhen Chen Hai-chun Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第9期1538-1543,共6页
Dedifferentiation of Schwann cells is an important feature of the response to peripheral nerve injury and specific negative myelination reg- ulators are considered to have a major role in this process. However, most e... Dedifferentiation of Schwann cells is an important feature of the response to peripheral nerve injury and specific negative myelination reg- ulators are considered to have a major role in this process. However, most experiments have focused on the distal nerve stump, where the Notch signaling pathway is strongly associated with Schwann cell dedifferentiation and repair of the nerve. We observed the phenotypic changes of Schwann cells and changes of active Notch signaling on the proximal stump during peripheral nerve repair using small gap conduit tubulization. Eighty rats, with right sciatic nerve section of 4 mm, were randomly assigned to conduit bridging group and control group (epineurium suture). Glial fibrillary acidic protein expression, in myelinating Schwann cells on the proximal stump, began to up-reg- ulate at 1 day after injury and was still evident at 5 days. Compared with the control group, Notchl mRNA was expressed at a higher level in the conduit bridging group during the first week on the proximal stump. Hesl mRNA levels in the conduit bridging group significantly increased compared with the control group at 3, 5, 7 and 14 days post-surgery. The change of the Notch intracellular domain shared a simi- lar trend as Hesl mRNA expression. Our results confirmed that phenotypic changes of Schwann cells occurred in the proximal stump. The differences in these changes between the conduit tubulization and epineurium suture groups correlate with changes in Notch signaling. This suggests that active Notch signaling might be a key mechanism during the early stage of neural regeneration in the proximal nerve stump. 展开更多
关键词 nerve regeneration Schwann cells nerve injury small gap conduit therapy CHITIN peripheral nerve injury Notch signaling Notch 1 HES1 glial fibrillary acidic protein S100 neural regeneration
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Biological conduit small gap sleeve bridging method for peripheral nerve injury: regeneration law of nerve fibers in the conduit 被引量:8
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作者 Pei-xun Zhang Li-ya A +5 位作者 Yu-hui Kou Xiao-feng Yin Feng Xue Na Han Tian-bing Wang Bao-guo Jiang 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第1期71-78,共8页
The clinical effects of 2-mm small gap sleeve bridging of the biological conduit to repair periph- eral nerve injury are better than in the traditional epineurium suture, so it is possible to replace the epineurium su... The clinical effects of 2-mm small gap sleeve bridging of the biological conduit to repair periph- eral nerve injury are better than in the traditional epineurium suture, so it is possible to replace the epineurium suture in the treatment of peripheral nerve injury. This study sought to identify the regeneration law of nerve fibers in the biological conduit. A nerve regeneration chamber was constructed in models of sciatic nerve injury using 2-mm small gap sleeve bridging of a biodegradable biological conduit. The results showed that the biological conduit had good his- tocompatibility. Tissue and cell apoptosis in the conduit apparently lessened, and regenerating nerve fibers were common. The degeneration regeneration law of Schwann cells and axons in the conduit was quite different from that in traditional epineurium suture. During the prime period for nerve fiber regeneration (2-8 weeks), the number of Schwann cells and nerve fibers was higher in both proximal and distal ends, and the effects of the small gap sleeve bridging method were better than those of the traditional epineurium suture. The above results provide an objec- tive and reliable theoretical basis for the clinical application of the biological conduit small gap sleeve bridging method to repair peripheral nerve injury. 展开更多
关键词 nerve regeneration peripheral nerve small gap AXONS Schwann cells repair injury biological conduit NSFC grants neural regeneration
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Strong coupling between height of gaps and thickness of thermal boundary layer in partitioned convection system 被引量:1
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作者 林泽鹏 包芸 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第9期270-275,共6页
A direct numerical simulation(DNS) method is used to calculate the partitioned convection system with Ra number ranging from 10^7 to 2×10^9.Using the boundary layer thickness to normalize the height of gaps d, we... A direct numerical simulation(DNS) method is used to calculate the partitioned convection system with Ra number ranging from 10^7 to 2×10^9.Using the boundary layer thickness to normalize the height of gaps d, we find a strong consistency between the variation of the TD number(the average value of the temperature in each heat transfer channel is averaged after taking the absolute values) with the change of the height of gaps and the variation of the TD number with the change of Ra number in partitioned convection.For a given thickness of partition, heights of gaps are approximately equal to 0.5 or 1 time of the thermal boundary layer thickness λθ at different Ra numbers.TD number representing temperature characteristics is almost the constant value, which means that TD number is a function of d/λθ only.Analysis of local temperature field of area in gaps shows that the temperature distribution in the gaps are basically the same when d/λθ is certain.The heat transfer Nu number of the system at d/λθ≈ 0.5 is larger than that of d/λθ≈ 1, both of them have the same scaling law with Ra number and Nu^Ra^0.25. 展开更多
关键词 partitioned CONVECTION SYSTEM HEIGHT of gapS thermal boundary layer TD number
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Analysis of the Influence Factors of Grain Supply-Demand Gap in China 被引量:2
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作者 Bingjun Li Weiming Yang 《Agricultural Sciences》 2018年第7期901-909,共9页
Based on the analysis of the grain supply and demand gap’s current situation in China, this paper establishes an indicator system for the influence factors of grain supply and demand gap. Then this paper calculates t... Based on the analysis of the grain supply and demand gap’s current situation in China, this paper establishes an indicator system for the influence factors of grain supply and demand gap. Then this paper calculates the correlation degree between the main grain varieties’ supply and demand gap and its influence factors. The results show that sown area and unit yield have the greatest impact on wheat supply and demand gap;per capita disposable income and unit yield have the greatest impact on corn supply and demand gap;per capita disposable income and agricultural mechanization level have the greatest impact on the supply and demand gap of soybean and rice. From the analysis results, we can obtain the difference between the factors affecting the grain supply and demand gap, and provide a certain theoretical basis and new ideas for the balance of grain supply and demand in China. 展开更多
关键词 ENTROPY Method GREY Correlation ANALYSIS DEMAND and Supply gap Influence FACTORS
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