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Integrative Zoology 2011年第1期6卷 56-62页

作者： Maria j.ALBO Alicia POSTIGLIONI Laboratory of Ethology Ecology and EvolutionClemente Estable Biological Research InstituteMontevideoUruguay Department of Genetics and Animal Breeding Faculty of VeterinaryUniversity of the RepublicMontevideoUruguay

Preliminary genetic studies in Trechaleidae spider family show high variation in sex chromosomes and high heterocigocity,suggesting high chromatin *** trechaleids Paratrechalea ornata,Trechalea bucculenta and Trechaleoides biocellata are present in *** offering nuptial gifts during courtship have been reported in *** and *** but not in *** gifts are an inherited trait probably highly affected by environmental factors,which play an important role in gene *** hypothesize that this trait could be associated with tissue-specific genes existing in *** investigate the male meiosis in these 3 species,their sex chromosome system and the effects of G-banding on their chromosomes,and elucidate genetic differences among *** stages of the 3 species were submitted to Giemsa-staining and G-banding *** observed a haploid number of n=11 in *** and n=13 in both *** and *** from the 3 species presented an X_(1)X_(2)0 sex chromosome system,which is suggested as ancestral in *** *** and ***,both sex chromosomes were together and aligned in parallel until the segregation during anaphase *** contrast to these species,sex chromosomes of *** usually remained distant from each other until diakinesis when they were observed associated in parallel *** G-bands were similar in *** and ***,and they both differed from those in *** special behavior of sex chromosomes in *** as well as the different G-banding pattern of this species suggests the existence of novel modifications in this species.

关键词： G-banding male meiosis Neotropical spiders sex chromosomes Trechaleidae

SOLVABILITY Of AN IMPLICIT fRACTIONAL INTEGRAL EQUATION VIA A MEASURE Of NONCOMPACTNESS ARGUMENT

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Acta Mathematica Scientia 2017年第1期37卷 195-204页

作者： juan j.NIETO Bessem SAMET facultade de Matemáticas Universidade de Santiago de CompostelaSantiago de Compostela 15782Spain faculty of Science King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia

In this paper,we study the existence of solutions to an implicit functional equation involving a fractional integral with respect to a certain function,which generalizes the Riemann-Liouville fractional integral and the Hadaniard fractional *** establish an existence result to such kind of equations using a generalized version of Darbo＇s theorem associated to a certain measure of *** examples are presented.

关键词： umplicit fractional integral equation measure of noncompactness Darbo'stheorem

Intervertebral disc development and disease-related genetic polymorphisms

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Genes & Diseases 2016年第3期3卷 171-177页

作者： jason W.Ashley Motomi Enomoto-Iwamoto Lachlan j.Smith Robert L.Mauck Danny Chan joseph Lee Martin f.Heyworth Howard An Yejia Zhang Department of Orthopedic Surgery Perelman School of MedicineUniversity of PennsylvaniaUSA Department of Surgery Division of Orthopaedic SurgeryChildren’s Hospital of PhiladelphiaPhiladelphiaPAUSA School of Biomedical Sciences The University of Hong KongHong Kong Department of Orthopedic Surgery University of ChicagoChicagoILUSA Corporal Michael j.Crescenz Veterans Affairs Medical Center PhiladelphiaPAUSA Department of Medicine Perelman School of MedicineUniversity of PennsylvaniaUSA Department of Orthopedic Surgery Rush University Medical CenterChicagoILUSA Department of Physical Medicine&Rehabilitation Perelman School of MedicineUniversity of PennsylvaniaUSA

The intervertebral disc(IVD)comprises a gelatinous inner core(nucleus pulposus;NP)and concentric rings(annulus fibrosus;Af).The NP,an important structure for shock absorption in the vertebrate spinal motion segment,can be traced back to the notochord in ontogenetic *** vertebrates,the notochord undergoes mucinoid changes,and had been considered vestigial until ***,observed correlations between IVD degeneration and back pain in humans have renewed interest in the IVD in biomedical *** its mechanical contribution to development,the notochord is also an essential signaling center,which coordinates formation of the neural tube and *** pertinent signaling molecules,particularly TGf-b and bone morphogenetic proteins(BMPs),continue to play roles in the adult tissues and have been utilized for tissue *** factors are major determinants of who will develop IVD degeneration and related back pain,and seem to correlate better with disc degeneration and back pain than do external forces on the *** summary,the spinal column is a landmark development in *** directing the development of the IVD may also contribute to its maintenance,degeneration,and ***,structural genes as well as genes responsible for maintenance of the structure are related to IVD ***,genes responsible for inflammation may play a dual role in exacerbating degeneration or facilitating repair responses depending on the context.

关键词： Back pain Development Intervertebral disc(IVD) Notochord Regeneration

Gas-phase electrocatalytic conversion of CO_2 to chemicals on sputtered Cu and Cu–C catalysts electrodes

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journal of Energy Chemistry 2019年第4期28卷 46-53页

作者： N.Gutiérrez-Guerra j.A.González j.C.Serrano-Ruiz E.López-fernández j.L.Valverde A.de Lucas-Consuegra Departamento de Ingeniería Química Facultad de Ciencias y Tecnologías Químicas Universidad de Castilla-La Mancha Instituto Regional de Investigación Científica Aplicada (IRICA) and Departamento de física Aplicada Universidad de Castilla-La Mancha Departamento de Ingeniería Universidad Loyola Andalucía

A novel gas-phase electrocatalytic cell containing a low-temperature proton exchange membrane(PEM)was developed to electrochemically convert CO_2into organic *** different Cu-based cathode catalysts(Cu and Cu–C)were prepared by physical vapor deposition method(sputtering)and subsequently employed for the gas-phase electroreduction of CO_2at different temperatures(70–90°C).The prepared electrodes Cu and Cu–C were characterized by X-ray diffraction(XRD),X-ray photoemission spectroscopy(XPS)and scanning electron microscopy(SEM).As revealed,Cu is partially oxidized on the surface of the samples and the Cu and Cu–C cathodic catalysts were comprised of a porous,continuous,and homogeneous film with nanocrystalline Cu with a grain size of 16 and 8 nm,*** influence of the applied current and temperature on the electro-catalytic activity and selectivity of these materials was *** the two investigated electrodes,the pure Cu catalyst film showed the highest CO_2specific electrocatalytic reduction rates and higher selectivity to methanol formation compared to the Cu–C electrode,which was attributed to the higher particle size of the former and lower Cu O/Cu *** obtained results show potential interest for the possible use of electrical renewable energy for the transformation of CO_2into valuable products using low metal loading Cu based electrodes(0.5 mg Cu cm^(-2))prepared by sputtering.

关键词： CO_2 valorization Electro-reduction Cu catalyst PEM Selectivity Methanol production

field investigation on effects of railway track geometric parameters on rail wear

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1846-1855页

作者： SADEGHI j. AKBARI B. School of Railway Engineering Iran University of Science and Technology Narmak Tehran Iran

Rail wear has dramatic impact on track performance, ride quality and maintenance costs. The amount of rail wear is influenced by various elements among which geometric parameters play an important role. The amount of wear in Iran’s railway lines and its imposed maintenance costs oblige us to make modifications on the various geometrical parameters. In order to ensure the effectiveness of these changes, it is necessary to investigate these parameters and their effects on the wear. This research is aimed at studying the effects of different track geometrical parameters on the vertical and lateral wear by conducting a three phase field investigation. The first phase was carried out at the switches of a station, the second phase at a straight line, and the third at a curved line out of the station. The results obtained are analyzed and the role of each track geometrical parameter in the rail wear is discussed. Recommendations for prevention or reduction of rail wear are presented.

关键词： Rail wear Vertical and lateral wear Superelevation Gauge Longitudinal slope Track geometry

Numerical and statistical approach for Casson-Maxwell nanofluid flow with Cattaneo-Christov theory

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Applied Mathematics and Mechanics(English Edition) 2021年第7期42卷 1063-1076页

作者： T.MUSHTAQ A.RAUf S.A.SHEHZAD f.MUSTAfA M.HANIf Z.ABBAS Department of Mathematics COMSATS University IslamabadVehari CampusVehari 61100Pakistan Department of Mathematics COMSATS University IslamabadSahiwal CampusSahiwal 57000Pakistan Department of Mathematics The Islamia University of BahawalpurBahawalpur 63100Pakistan

The rheological features of an incompressible axi-symmetric Casson-Maxwell nanofluid flow between two stationary disks are *** lower permeable disk is located at z=-a,while the upper disk is placed at z=*** the disks are porous and subjected to uniform *** fluid properties such as thermal conductivity vary with *** Cattaneo-Christov thermal expression is implemented along with the Buongiorno nanofluid *** operating the similarity functions,the reduced form of the fluid model in terms of ordinary differential equations is obtained and solved by the bvp4 c numerical *** physical quantities are demonstrated graphically on the velocity and temperature ***-dimensional flow arrangements and twodimensional contour patterns against several dimensionless variables are also *** numerical values of the local Nusselt and Sherwood numbers for various quantities are presented in tabular *** intensity of the linear relationship between the Nusselt and Sherwood numbers is assessed through Pearson’s product-moment correlation *** statistical implication of the linear association between variables is also examined by the t-test statistic approach.

关键词： Casson-Maxwell fluid porous disk Buongiorno theory variable thermal conductivity Cattaneo-Christov model uniform injection

Assessing support alternatives for longwall gateroads subject to changing stress

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International journal of Mining Science and Technology 2021年第1期31卷 103-110页

作者： Gabriel S.Esterhuizen I.Berk Tulu Dave f.Gearhart Heather Dougherty Mark Van Dyke National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA West Virginia University MorgantownWV 26506USA

Longwall gateroad entries are subject to changing horizontal and vertical stress induced by redistribution of loads around the extracted *** stress changes can result in significant deformation of the entries that may include roof sag,rib dilation,and floor *** operators install different types of supports to control the ground response and maintain safe access and ventilation of the longwall *** paper describes recent research aimed at quantifying the effect of longwall-induced stress changes on ground stability and using the information to assess support *** research included monitoring of ground and support interaction at several operating longwall mines in the U.S.,analysis and calibration of numerical models that adequately represent the bedded rock mass,and observation of the support systems and their response to changes in *** models were then used to investigate the impact of geology and stress conditions on ground deformation and support response for various depths of cover and geologic *** research results were summarized in two regression equations that can be used to estimate the likely roof deformation and height of roof yield due to longwall-induced stress *** information is then used to assess the ability of support systems to maintain the stability of the *** application of the method is demonstrated with a retrospective analysis of the support performance at an operating longwall mine that experienced a headgate roof *** method is shown to produce realistic estimates of gateroad entry stability and support performance,allowing alternative support systems to be assessed during the design and planning stage of longwall operations.

关键词： Longwall Gateroad Support design Coal Standing support

Dependency-aware unequal erasure protection codes

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 27-33页

作者： BOUABDALLAH Amine LACAN jérme Laboratory for Analysis and Architecture of Systems Toulouse 31077 France Applied Mathematics and Computer Science DepartmentENSICAToulouse 31056France Telecommunications for Space and AeronauticToulouse 31000France

Classical unequal erasure protection schemes split data to be protected into classes which are encoded independently. The unequal protection scheme presented in this paper is based on an erasure code which encodes all the data together according to the existing dependencies. A simple algorithm generates dynamically the generator matrix of the erasure code according to the packets streams structure, i.e., the dependencies between the packets, and the rate of the code. This proposed erasure code was applied to a packetized MPEG4 stream transmitted over a packet erasure channel and compared with other classical protection schemes in terms of PSNR and MOS. It is shown that the proposed code allows keeping a high video quality-level in a larger packet loss rate range than the other protection schemes.

关键词： Data dependencies integration Unequal erasure protection (UEP) Lossy networks Reliable video transmissions MPEG4 video codec

Apoptosis and DNA damage in human spermatozoa

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Asian journal of Andrology 2011年第1期13卷 36-42页

作者： R john Aitken Adam j Koppers ARC Centre of Excellence in Biotechnology and Development Priority Research Centre in Reproductive Science Discipline of Biological Sciences School of Environmental and Life Sciences University of Newcastle Callaghan NSW 2308 Australia Department of Anatomy and Developmental Biology School of Biomedical Sciences Monash University Clayton VIC 3800 Australia

DNA damage is frequently encountered in spermatozoa of subfertile males and is correlated with a range of adverse clinical outcomes including impaired fertilization, disrupted preimplantation embryonic development, increased rates of miscarriage and an enhanced risk of disease in the progeny. The etiology of DNA fragmentation in human spermatozoa is closely correlated with the appearance of oxidative base adducts and evidence of impaired spermiogenesis. We hypothesize that oxidative stress impedes spermiogenesis, resulting in the generation of spermatozoa with poorly remodelled chromatin. These defective cells have a tendency to default to an apeptotic pathway associated with motility loss, caspase activation, phosphatidylserine exteriorization and the activation of free radical generation by the mitochondria. The latter induces lipid peroxidation and oxidative DNA damage, which then leads to DNA fragmentation and cell death. The physical architecture of spermatozoa prevents any nucleases activated as a result of this apoptotic process from gaining access to the nuclear DNA and inducing its fragmentation. It is for this reason that a majority of the DNA damage encountered in human spermatozoa seems to be oxidative. Given the important role that oxidative stress seems to have in the etiology of DNA damage, there should be an important role for antioxidants in the treatment of this condition. If oxidative DNA damage in spermatozoa is providing a sensitive readout of systemic oxidative stress, the implications of these findings could stretch beyond our immediate goal of trying to minimize DNA damage in spermatozoa as a prelude to assisted conception therapy.

关键词： apoptosis DNA damage oxidative stress spermatozoa

Sodium arsenite reduces severity of dextran sulfate sodium-induced ulcerative colitis in rats

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journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第4期9卷 341-350页

作者： joshua j. MALAGO Hortensia NONDOLI Department of Pathology faculty of Veterinary Medicine Sokoine University of Agriculture P.O. Box 3203 Morogoro Tanzania Regional Immigration Office P.O. Box 649 Mtwara Tanzania

The histopathological features and the associated clinical findings of ulcerative colitis (UC) are due to persistent inflammatory response in the colon mucosa. Interventions that suppress this response benefit UC patients. We tested whether sodium arsenite (SA) benefits rats with dextran sulfate sodium (DSS)-colitis. The DSS-colitis was induced by 5% DSS in drinking water. SA (10 mg/kg; intraperitoneally) was given 8 h before DSS treatment and then every 48 h for 3 cycles of 7, 14 or 21 d. At the end of each cycle rats were sacrificed and colon sections processed for histological examination. DSS induced diarrhea, loose stools, hemoccult positive stools, gross bleeding, loss of body weight, loss of epithelium, crypt damage, depletion of goblet cells and infiltration of inflammatory cells. The severity of these changes increased in the order of Cycles 1, 2 and 3. Treatment of rats with SA significantly reduced this severity and improved the weight gain.

关键词： Ulcerative colitis Dextran sulfate sodium Sodium arsenite Rats