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The effect of global warming on beef production in developing countries of the southern hemisphere

Natural Science 2013年第1期5卷 106-119页

作者： M.M.Scholtz c.McManus K-J.Leeuw H.Louvandini L.Seixas c.b.de melo A.Theunissen F.W.c.Neser ARc-Animal Production Institute IreneSouth Africa University of the Free State BloemfonteinSouth Africa Insituto Nacional de ciencia e Tecnologia-InformacaoGenetico-Sanitaria da Pecuaria brasileira Brazil departamento de Zootecnia Universidade Federal de Rio Grande do SulPorto AlegreBrazil centro de Energia Nuclear na Agricultura Universidade de Sao PauloPiracicabaBrazil Faculdade de Agronomia e Medicina Veterinaria Universidade de BrasiliaBrasiliaBrazil Northern cape department of Agricultural Land Reform and Rural DevelopmentJan KempdorpSouth Africa

developing countries from the southern hemisphere will be confronted by the same beef production challenges caused by global warming, because these countries are at the same geographical positions in southern latitudes. Global warming is expected to have a more extreme effect on the southern hemisphere than on other continents and will have a negative effect on the beef production environments in these countries. The negative effects will include high ambient temperatures, nutritional stress and altered patterns of animal diseases. Heat stress in beef cattle on veld/savannah is expected to increase as a result of changing weather patterns on a global and regional scale. This may negatively influence food production from beef cattle for the human food chain. Negative effects of increased temperatures and thus heat stress can include lower reproductive rates and weaning weights. The effect of heat stress can be partly addressed by nutritional strategies, such as replacing rapid fermentable carbohydrates with saturated fatty acids and the feeding of more by-pass protein and dietary electrolytes. Global warming will also alter the distribution pattern of animal diseases and the vectors of some of these diseases. This may even include the spread to South American countries. Likewise the nutritional value of natural pastures may be influenced. The effect of global warming on the quality of pastures will depend on whether the global warming is a result of increased carbon dioxide levels or not. An improved understanding of the adaptation of beef cattle to their production environments is important, but adaptation is complex and thus difficult to measure. Fortunately, several proxy-indicators for adaptation such as reproductive, production and health traits are available. The selection of animals and genotypes that are better adapted to the production system, including heat stress, is possible and should be persuade to ensure sustainable beef production in hotter climates.

关键词： Adaptation Animal diseases Heat Stress Mitigation Strategies Nutritional Stress

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Hydrocarbon indication in Rio bonito Formation sandstone:Implication for cO_(2)storage in São Paulo,brazil

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Energy Geoscience 2024年第1期5卷 331-341页

作者： Richardson M.Abraham-A Haline V.Rocha Saulo b.de Oliveira colombo c.G.Tassinarri Orlando c.da Silva Institute of Energy and Environment University of São PauloSão PauloBrazil Research centre for Greenhouse Gas Innovation University of São PauloSão PauloBrazil

São Paulo State has witnessed cO_(2)storage-based investigations considering the availability of suitable geologic structures and proximity to primary cO_(2)source sinks related to bioenergy and carbon capture and storage(bEccS)*** current study presents the hydrocarbon viability evaluations and cO_(2)storage prospects,focusing on the sandstone units of the Rio bonito *** objective is to apply petrophysical evaluations with geochemical inputs in predicting future hydrocarbon(gas)production to boost cO_(2)storage within the study *** study used data from eleven wells with associated wireline logs(gamma ray,resistivity,density,neutron,and sonic)to predict potential hydrocarbon accumulation and fluid mobility in the investigated *** samples(shale and carbonate)obtained from depths>200 m within the study location have shown bitumen *** geochemistry data of the Rio bonito Formation shale beds suggest they are potential hydrocarbon source rocks and could have contributed to the gas accumulations within the sandstone *** drilled well data,e.g.,cb-1-SP and TI-1-SP,show hydrocarbon(gas)presence based on the typical resistivity and the combined neutron-density responses at depths up to 3400 m,indicating the possibility of other hydrocarbon members apart from the heavy oil(bitumen)observed from the near-surface rocks *** the three-dimensional(3-D)model,the free fluid indicator(FFI)is more significant towards the southwest and southeast of the area with deeper depths of occurrence,indicating portions with reasonable hydrocarbon recovery rates and good prospects for cO_(2)injection,circulation and permanent ***,future studies based on contemporary datasets are required to establish the hydrocarbon viability further,foster gas production events,and enhance cO_(2)storage possibilities within the region.

关键词： Paranábasin Hydrocarbon indication Sandstone reservoirs Rio bonito Formation cO_(2)storage Hydrocarbon recovery factor Fluid injection rate

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black hole shadows in Einstein-bel-Robinson gravity

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chinese Physics c 2024年第5期48卷 272-283页

作者： b.Hamil b.c.Lütfüoğlu Laboratoire de Physique Mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given by higher-order scalar curvature corrections are believed to bear important consequences. Einstein-bel-Robinson (EbR) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric black hole solutions using perturbative methods. In this study, inspired by their work, we investigate AdS black hole shadows in EbR gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same problem in the presence of plasma, because the black holes are thought to be surrounded by a medium that changes the geodesic of photons.

关键词： black hole shadows Einstein-bel-Robinson gravity plasma

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New avenues for the treatment of immunotherapy-resistant pancreatic cancer

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1134-1153页

作者： Luis Guilherme de Oliveira Silva Fabian Fellipe bueno Lemos Marcel Silva Luz Samuel Luca Rocha Pinheiro Mariana dos Santos calmon Gabriel Lima correa Santos Gabriel Reis Rocha Fabrício Freire de melo Instituto Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil

Pancreatic cancer(Pc)is characterized by its extremely aggressive nature and ranks 14th in the number of new cancer cases ***,due to its complexity,it ranks 7th in the list of the most lethal cancers *** pathogenesis of Pc involves several complex processes,including familial genetic factors associated with risk factors such as obesity,diabetes mellitus,chronic pancreatitis,and *** in genes such as KRAS,TP53,and SMAD4 are linked to the appearance of malignant cells that generate pancreatic lesions and,consequently,*** this context,some therapies are used for Pc,one of which is immunotherapy,which is extremely promising in various other types of cancer but has shown little response in the treatment of Pc due to various resistance mechanisms that contribute to a drop in immunotherapy *** is therefore clear that the tumor microenvironment(TME)has a huge impact on the resistance process,since cellular and non-cellular elements create an immunosuppressive environment,characterized by a dense desmoplastic stroma with cancerassociated fibroblasts,pancreatic stellate cells,extracellular matrix,and immunosuppressive *** to this are genetic mutations in TP53 and immunosuppressive factors that act on T cells,resulting in a shortage of cD8+T cells and limited expression of activation markers such as *** this way,finding new strategies that make it possible to manipulate resistance mechanisms is ***,techniques such as the use of TME modulators that block receptors and stromal molecules that generate resistance,the use of genetic manipulation in specific regions,such as microRNAs,the modulation of extrinsic and intrinsic factors associated with T cells,and,above all,therapeutic models that combine these modulation techniques constitute the promising future of Pc ***,this study aims to elucidate the main mechanisms of resistance to immunotherapy in Pc and new ways of manipulating thi

关键词： Pancreatic cancer Immunotherapy Resistance Tumor microenvironment manipulation combined immunotherapy

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correcting distortions of thin-walled machined parts by machine hammer peening

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chinese Journal of Aeronautics 2024年第6期37卷 439-453页

作者： Aitor MADARIAGA Mikel cUESTA Gorka ORTIZ-de-ZARATE Eneko SAENZ-de-ARGANDONA denis SORIANO Michael b.PRIME Pedro Jose ARRAZOLA department of Materials University of ManchesterOxford RoadManchester M139PLUnited Kingdom Mechanical and Industrial Production department Faculty of EngineeringMondragon UnibertsitateaArrasate 20500Spain Los Alamos National Laboratory Los AlamosNew MexicoUSA

Thin-walled aerostructural components frequently get distorted after the machining *** to correct distortions or eventually rejecting parts significantly increases the *** paper proposes a new approach to correct distortions in thin-walled components by strategically applying hammer peening on target surfaces of a machined *** alloy 7475-T7351 was chosen for this *** study was divided in two ***,the residual stresses(RS)induced by four different pneumatic hammer peening conditions(modifying the stepover distance and initial offset)were characterised in a test coupon,and one of the conditions was selected for the next *** the second stage,a FEM model was used to predict distortions caused by machining in a representative ***,the RS induced by hammer peening were included in an FEM model to define two hammer peening strategies(varying the coverage area)to analyse the capability to reduce *** workpieces were machined and then treated with the simulated hammer peening strategies for experimental *** in the test coupon showed that pneumatic hammer peening can generate high compressive RS(-50 to350 MPa)up to 800 lm depth,with their magnitude increasing with a reduced stepover *** of hammer peening over 4% of the surface of the representative workpiece reduced the machininginduced distortions by 37%,and a coverage area of 100% led to and overcorrection by a factor of *** confirms that hammer peening can be strategically applied(in target areas and changing the percentage of coverage)to correct low or severe distortions.

关键词： Aeronautics Machining,Hammer Peening Aluminium alloy Distortions Residual Stress

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Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 197-216页

作者： c.G.PAVITHRA b.J.GIREESHA M.L.KEERTHI department of PG Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India department of Mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTM) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTM) trihybrid nanofluid magnetic field

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Laminated Solid Timber Slab with Transverse Prestressing Using the Strategy of Interleaved Vertical Displacement of Lamellae

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Journal of civil Engineering and Architecture 2024年第4期18卷 186-198页

作者： bianca bispo dos Reis Jorge Daniel de melo Moura Marcos Vinício de camargo Everaldo Pletz Graduate Program in Architecture and Urbanism Londrina State UniversityJardim Portal de Versalhes 1Londrina 86057-970PRBrazil department of civil Engineering Federal Technological University of Paraná(UTFPR)Apucarana 86812-460PRBrazil Retired professor department of Structural Engineering Londrina State UniversityLondrina 86057-970PRBrazil

This article presents a study on the structural behavior of transversely prestressed laminated timber slabs,focusing on an innovative approach:vertically misaligned *** misalignment,achieved by sliding vertically the wooden lamellae rather than aligning them,enhances the slab’s cross-section moment of inertia,thereby improving load-bearing capacity and *** involved two groups of structural size specimens:one with vertically aligned lamellae(control group)and the other with misaligned lamellae(study group).Results showed the study group exhibited 42%superior stiffness and 10%less load capacity compared to the *** typically occurred individually in the lamellae,particularly in those with defects or lower modulus of elasticity,concentrated in the middle third of the slabs’free span where tensile stresses *** a higher number of failed lamellae,the study group demonstrated promising *** of prestressing bar indicated no damage at all in the thread,suggesting potential for reducing bar *** findings offer crucial insights into applying these slabs in timber construction as well as to any kind of construction.

关键词： Transversal prestressed slabs wooden construction plantation wood flexural testing design methodology

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Urotensin-I suppresses the hypothalamo-hypophyseal-ovarian axis in the Mozambique tilapia,Oreochromis mossambicus

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Aquaculture and Fisheries 2024年第3期9卷 339-346页

作者： Jyoti A.Kumbar c.b.Ganesh Neuroendocrinology Research Laboratory Department of Studies in ZoologyKarnatak UniversityDharwad580003India

Urotensin-I(UI)is a peptide belonging to the corticotropin-releasing hormone family,produced in the urophysis of *** investigation was undertaken to examine the effect of UI on the hypothalamo-hypophyseal-ovarian axis in the Mozambique tilapia,a cichlid *** the first experiment,administration of UI(2μg/100μL saline)for 22 days caused a significant reduction in the number of follicles at stages I,II,III(previtellogenic),IV(vitellogenic),and V(preovulatory),concomitant with a significant increase in the percent atresia of follicles at stages II,III,and IV than in *** the pituitary,gonadotropin-releasing hormone(GnRH)-positive fibres were detected in the proximal pars distalis(PPD)in both controls and UI-treated fish;however,there was a significant reduction in the intensity and percent area of GnRH-immunoreactive fibres in fish treated with UI compared with *** serum luteinizing hormone(LH)level was significantly lower,whereas a significant rise in the serum level of cortisol was noticed in UI-treated fish compared with *** the second experiment,treatment with a low dose of UI(10 mM)did not affect the number of AcTH-secreting cells in vitro,but the number of these cells was significantly higher in high-dose UI(50 mM)-treated pituitaries compared to ***,the present investigation reveals for the first time that the treatment of UI affects the follicular development process through the downregulation of the GnRH-LH axis and activation of the pituitary-interrenal pathway in teleosts.

关键词： Urotensin-I cRH family Gonadotropin-releasing hormone Luteinizing hormone Ovary Oreochromis mossambicus

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Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystems 2024年第1期11卷 110-119页

作者： J.Touche c.calvaruso P.de Donato M.-P.Turpault INRAE BEFF-54000NancyFrance UMR 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the coming decades in Western Europe may disturb forest biogeochemical cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the maintenance of tree nutrition are poorly *** experiment in a beech forest in Meuse(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim was to identify potential nutritional consequences of droughts for *** nutrient dynamics,including resorption,chemistry of green and senesced leaves,foliar absorption and leaching in mature beech stands from 2012 to 2019 allowed us to compare the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by almost a third of the potassium(K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the coming decades,there will be a risk of potassium deficiency in trees,as already observed in a rainfall exclusion experiment on the same study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is more likely to improve tree *** calcium(ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought beech forest canopy Resorption Foliar leaching Senesced leaves Nutrition

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consumer transparency in the production chain for plant varieties produced using new genomic techniques

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abIOTEcH 2024年第2期5卷 239-246页

作者： J.M.Lukasiewicz c.c.M.van de Wiel L.A.P.Lotz M.J.M.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically Modified Organisms Directive(2001/18/Ec)in the European *** the proposal of the European commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques consumer transparency Plant products

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