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Macroinvertebrate Community Index (MCI) and Quantitative Macroinvertebrate Community Index (QMCI) Analysis: A Comparative Study between Le Afe and Mulivaifagatoloa Rivers, Upolu Island, Samoa

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journal of Geoscience and Environment Protection 2024年第8期12卷 149-167页

作者： S. taupega-Satau P. Amosa A. Leauga j. Nunufolau t. Veni Nun Yan Department of Science National University of Samoa Apia Samoa Office of the vice Chancellor National University of Samoa Apia Samoa Department of Information technology and Systems National University of Samoa Apia Samoa

the diversity of Samoa’s freshwater macroinvertebrates remains largely unexplored, with past studies focusing on specific species without comprehensive cataloguing. this research evaluated the health of Upolu Island’s rural rivers through macroinvertebrate analysis, particularly in the Le Afe and Mulivaifagatoloa Rivers. Collaborating with Samoa’s Water Resources Division in the Ministry of Natural Resources and Environment (MNRE), three sites along each river were sampled, representing a gradient from pristine to anthropogenically impacted areas. A total of 2953 macroinvertebrates were collected and classified into five categories using established identification keys. the Macroinvertebrate Community Index (MCI) and Quantitative Macroinvertebrate Community Index (QMCI) were applied for analysis. the results showed no clear pattern of pollutant-sensitive species prevalence or decline in less disturbed rivers. High MCI scores with low QMCI values indicated numerous low-scoring species, while the opposite suggested a richness of high-scoring taxa. Although MCI and QMCI are tools for monitoring freshwater health, this study lays the groundwork for future research to categorize Samoan macroinvertebrates and assign tolerance scores based on their presence in varying river conditions. .

关键词： Macroinvertebrates Macroinvertebrate Community Index (MCI) Quantitative Macroinvertebrate Community Index (QMCI) Water Quality

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Dissociation cross sections ofψ(3770),ψ(4040),ψ(4160),andψ(4415)mesons with nucleons

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Communications in theoretical Physics 2024年第4期76卷 93-112页

作者： Ruo-Qing Ding Xiao-Ming Xu H j Weber Department of Physics Shanghai UniversityBaoshanShanghai 200444China Department of Physics University of VirginiaCharlottesvilleVA 22904United States of America

We study the dissociation of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons in collision with nucleons, which takes place in high-energy proton-nucleus collisions. the quark interchange between a nucleon and a ■ meson leads to the dissociation of the ■ meson. We consider the reactions:■, and■, where R stands for ψ(3770), ψ(4040), ψ(4160), or ψ(4415). A reaction of a neutron and a ■ meson corresponds to a reaction of a proton and the ■ meson by replacing the up quark with the down quark and vice versa. transition-amplitude formulas are derived from the S-matrix *** cross sections are calculated with the transition amplitudes for scattering in the prior form and in the post form. the cross sections relate to nodes in the radial wave functions of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons.

关键词： inelastic nucleon-charmonium scattering quark interchange relativistic constituent quark potential model

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Gene therapy for spinal muscular atrophy:perspectives on the possibility of optimizing SMN1 delivery to correct all neurological and systemic perturbations

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Neural Regeneration Research 2025年第7期20卷 2011-2012页

作者： Sharon j.Brown Rafael j.Yáñez-Muñoz Heidi R.Fuller School of Pharmacy and Bioengineering Keele UniversityKeeleUK Wolfson Center for Inherited Neuromuscular Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular atrophy(SMA)is a genetic condition that results in selective lower motor neuron loss with concomitant muscle weakness and *** genetic cause of SMA was understood in 1995 when loss or impairment of the survival motor neuron 1(SMN1)gene was identified as the main contributing factor(Lefebvre et al.,1995).this,in combination with the discovery that humans have a“back-up”gene,SMN2,which can produce low levels(approximately 10%)of the full-length functional SMN protein,has led to the generation of SMA-specific gene *** was traditionally classified according to age of symptom onset and developmental milestones achieved,with life expectancy and severity varying between ***,SMN2 copy number is used as a proxy for the prediction of disease severity,with higher SMN2 copy number typically being associated with reduced severity of SMA,although this relationship is not absolute:some individuals with low SMN2 copy number have less severe SMA phenotypes and vice ***,the etiology of SMA is further complicated by other factors,such as non-typical nucleotide variants and SMN2-independent modifiers of disease severity.

关键词： atrophy traditionally absolute

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Utilization of RNA sequencing to investigate olfactory dysfunction in chronic rhinosinusitis without nasal polyps:A pilot study

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World journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 29-36页

作者： jorge A.Gutierrez III jeremy L.Barth Rodney j.Schlosser thomas S.Edwards timothy L.Smith Zachary M.Soler Department of Otolaryngology-Head and Neck Surgery Medical University of South CarolinaCharlestonSouth CarolinaUSA Department of Regenerative Medicine&Cell Biology Medical University of South CarolinaCharlestonSouth CarolinaUSA Department of Otolaryngology-Head and Neck Surgery Oregon Health&Science UniversityPortlandOregonUSA

Objectives:Prior research on olfactory dysfunction in chronic rhinosinusitis(CRS)has focused on patients with polyps and suggests that direct inflammation of the olfactory cleft mucosa plays a contributory *** purpose of this study was to evaluate gene expression in superior turbinate mucosal specimens,comparing normosmic and dysosmic CRS patients without polyps(CRSsNP).Methods:tissue samples were obtained from the superior turbinates of patients with CRSsNP at the time of endoscopic sinus *** subsequently underwent RNA sequencing and functional analysis to investigate biological pathways associated with differentially expressed genes between dysosmic(n=7)and normosmic(n=4)***:Differential gene expression analysis comparing dysosmic and normosmic CRSsNP patients showed upregulation of 563 genes and downregulation of 327 *** stringent criteria for multiple comparisons,one upregulated gene(Immediate Early Response 3[IER3])had an false discovery rate(FDR)correction adjustedP value considered statistically significant(Ptome functional analysis revealed eight biological pathways significantly different between dysosmic and normosmic patients(Ption)including IL-4 and IL-13 signaling,IL-10 signaling,and rhodopsin-like ***:RNA sequencing of the superior turbinates in patients with CRSsNP can provide valuable information regarding biological pathways and genes involved in olfactory *** study supports literature suggesting that type 2 inflammation may play a role in olfactory dysfunction in at least some patients with *** study also prompts questions regarding the role of IL-10,rhodopsin-like receptors,andIER3 in the pathogenesis of olfactory dysfunction.

关键词： chronic rhinosinusitis without nasal polyps olfactory dysfunction RNA sequencing

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Spatial Localization for Nonlinear Dynamical Stochastic Models for Excitable Media

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Chinese Annals of Mathematics,Series B 2019年第6期40卷 891-924页

作者： Nan CHEN Andrew j.MAjDA Xin t.tONG Department of Mathematics University of Wisconsin-MadisonWI53705USA Department of Mathematics and Center for Atmosphere Ocean Science Courant Institute of Mathematical SciencesNew York UniversityNew YorkNY10012USA Center for Prototype Climate Modeling New York University AbuDhabiSaadiyat IslandAbuDhabiUAE Department of Mathematics National University of SingaporeSingapore 119076Singapore

Nonlinear dynamical stochastic models are ubiquitous in different *** statistical properties are often of great interest,but are also very challenging to *** excitable media models belong to such types of complex systems with large state dimensions and the associated covariance matrices have localized *** this article,a mathematical framework to understand the spatial localization for a large class of stochastically coupled nonlinear systems in high dimensions is *** mathematical analysis shows that the local effect from the diffusion results in an exponential decay of the components in the covariance matrix as a function of the distance while the global effect due to the mean field interaction synchronizes different components and contributes to a global *** analysis is based on a comparison with an appropriate linear surrogate model,of which the covariance propagation can be computed *** important applications of these theoretical results are *** are the spatial averaging strategy for efficiently sampling the covariance matrix and the localization technique in data *** examples of a linear model and a stochastically coupled Fitz Hugh-Nagumo model for excitable media are adopted to validate the theoretical *** latter is also used for a systematical study of the spatial averaging strategy in efficiently sampling the covariance matrix in different dynamical regimes.

关键词： Large state dimensions Diffusion Mean field interaction Spatial averaging strategy Efficiently sampling

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Mechanical and histological properties of an electrospun scaffold with a modified surface by plasma polymerization implanted in an in vivo model

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BIOCELL 2022年第3期46卷 829-836页

作者： marÍA G.FLORES-SÁNCHEZ ROBERtO OLAYO j.MORALES-CORONA AtLÁNtIDA M.RAYA-RIVERA DIEGO R.ESQUILIANO-RENDÓN Research vice-Rectory Faculty of EngineeringUniversity La Salle México06140México Department of Physics Metropolitan Autonomous University09340México Department of tissue Engineering Child Hospital of México Federico Gómez06720México

this article presents the construction of scaffolds composed of polylactic acid(PLA)with different concentrations of hydroxyapatite(HA)by electrospinning,which were superficially modified with polypyrrole(PPy/I)by plasma polymerization.A preliminary study was conducted of the biological and mechanical behavior of the scaffolds when they were implanted in the back of rabbits for 30 days;bone cells differentiated from mesenchymal stem cells(MSCs)were *** bone cell and scaffold structures were characterized by histological,immunohistochemical,and mechanical stress ***–eosin staining showed good tissue *** immunohistochemical tests highlighted the presence of the main bone tissue proteins,such as collagen,osteocalcin,and *** PLA/HA scaffolds were observed to exhibit cell adhesion and proliferation properties;however,the response was much better in the scaffolds that had a higher concentration of HA and that were coated with PPy/*** results of the mechanical tests of the scaffolds indicated that the plasma treatment improved the adhesion and cell proliferation properties and contributed to the mechanical support,allowing the formation of neotissues with good viability of cell growth.

关键词： Hydroxyapatite Polylactic acid pyrrole Electrospinning Surface activation

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Effect of equal channel angular extrusion on Al-6063 bending fatigue characteristics

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International journal of Minerals,Metallurgy and Materials 2015年第4期22卷 395-404页

作者： j.Nemati G.H.Majzoobi S.Sulaiman B.t.H.t.Baharudin M.A.Azmah Hanim Department of Mechanical and Manufacturing Engineering University Putra Malaysia Engineering Faculty Bu-Ali Sina University School of Mechanics Islamic Azad UniversityTakestan Branch

the purpose of this investigation was to refine the grains of annealed 6063 aluminum alloy and to improve its yield stress and ul- timate strength. this was accomplished via the equal channel angular extrusion （ECAE） process at a temperature of 200℃ using route A, with a constant ram speed of 30 mm/min through a die angle of 90° between the die channels for as many as 6 passes. the experiments were conducted on an Avery universal testing machine. the results showed that the grain diameter decreased from 45 μm to 2.8 μm after 6 extru- sion passes. the results also indicated that the major improvement in fatigue resistance occurred after the first pass. the subsequent passes improved the fatigue life but at a considerably lower rate. A maximum increase of 1100% in the case of low applied stresses and an ap- proximately 2200% increase in fatigue resistance in the case of high applied stresses were observed after 5 passes. the improvement of fa- tigue resistance is presumed to be due to （1） a reduction in the size and the number of Si crystals with increasing number of ECAE passes, （2） the aggregation of Cu during the ECAE process, （3） the formation and growth of CuA12 grains, and （4） grain refinement of the A1--6063 alloy during the ECAE process.

关键词： aluminum alloys equal channel angular pressing bending fatigue life grain size microstructure

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Improvements in the microstructure and fatigue behavior of pure copper using equal channel angular extrusion

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International journal of Minerals,Metallurgy and Materials 2014年第6期21卷 569-576页

作者： j.Nemati G.H.Majzoobi S.Sulaiman B.t.H.t.Baharudin M.A.Azmah Hanim Department of Mechanical and Manufacturing Engineering Universiti Putra Malaysia School of Mechanics Islamic Azad UniversityTakestan Branch348194 9479 Takestan Iran

In this study, annealed pure copper was extruded using equal channel angular extrusion （ECAE） for a maximum of eight passes. the fatigue resistance of extruded specimens was evaluated for different passes and applied stresses using fatigue tests, fractography, and metallography. the mechanical properties of the extruded material were obtained at a tensile test velocity of 0.5 mm/min. It was found that the maximum increase in strength occurred after the 2nd pass. the total increase in ultimate strength after eight passes was 94%. the results of fatigue tests indicated that a significant improvement in fatigue life occurred after the 2nd pass. In subsequent passes, the fatigue life con-tinued to improve but at a considerably lower rate. the improved fatigue life was dependent on the number of passes and applied stresses. For low stresses （or high-cycle fatigue）, a maximum increase in fatigue resistance of approximately 500%was observed for the extruded material after eight passes, whereas a maximum fatigue resistance of 5000%was obtained for high-applied stresses （or low-cycle fatigue）. Optical microscopic examinations revealed grain refinements in the range of 32 to 4 μm. A maximum increase in impact energy absorption of 100%was achieved after eight passes. Consistent results were obtained from fractography and metallography examinations of the ex-truded material during fatigue tests.

关键词： copper equal channel angular extrusion fatigue of materials grain size grain refinement fracture toughness

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Analysis of the factors affecting LiDAR DtM accuracy in a steep shrub area

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International journal of Digital Earth 2011年第6期4卷 521-538页

作者： j.Estornell L.A.Ruiz B.Vela´zquez-martı´ t.Hermosilla Departamento de Ingenierı´a Cartogra´fica Geodesia y Fotogrametrı´aUniversidad Polite´cnica de ValenciaCamino de Vera s/nValencia 46022Spain Departamento de Ingenierı´a Rural y Agroalimentaria Universidad Polite´cnica de ValenciaValenciaSpain

the creation of a quality Digital terrain Model(DtM)is essential for representing and analyzing the Earth in a digital *** continuous improvements in the acquisition and the potential of airborne Light Detection and Ranging(LiDAR)data are increasing the range of applications of this technique to the study of the Earth *** aim of this study was to determine the optimal parameters for calculating a DtM by using an iterative algorithm to select minimum elevations from LiDAR data in a steep mountain area with shrub *** parameters were:input data type,analysis window size,and height *** effects of slope,point density,and vegetation on DtM accuracy were also *** results showed that the lowest root mean square error(RMSE)was obtained with an analysis window size of 10 m,5 m,and 2.5 m,rasterized data as input data,and height thresholds equal to or greater than 1.5 *** parameters showed a RMSE of 0.19 *** terrain slope varied from 010%to 5060%,the RMSE increased by 0.11 *** RMSE decreased by 0.06 m when point density was increased from 4 to 8 points/m2,and increased by 0.05 m in dense vegetation areas.

关键词： LiDAR digital earth Digital terrain Model(DtM) filtering 3-D representation

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一本论述经济学方法的优秀著作——《经济学家应该做什么?》一书评介

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经济学家 1989年第1期 112-115,118页

作者：罗根基西南财经大学经济研究所

本文介绍了美国著名经济学家、1986年诺贝尔经济学奖获得者j·M·布坎南所著《经济学家应该做什么?》一书,尤其是对布坎南关于经济学方法论的研究作了中肯的评介。

关键词：经济学方法论经济学家布坎南资产阶级经济学诺贝尔经济学奖经济理论经济分析方法公共选择理论市场理论效用函数

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