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the market for amino acids: understanding supply and demand of substrate for more efficient milk protein synthesis

Journal of Animal Science and Biotechnology 2021年第1期12卷 37-48页

作者： Virginia l.Pszczolkowski Sebastian i.Arriola Apelo Department of Animal and Dairy Sciences University of Wisconsin-MadisonMadisonWIUSA Endocrinology and Reproductive Physiology Graduate training Program University of Wisconsin-MadisonMadisonWIUSA

For dairy production systems, nitrogen is an expensive nutrient and potentially harmful waste product. With three quarters of fed nitrogen ending up in the manure, significant research efforts have focused on understanding and mitigating lactating dairy cows' nitrogen losses. Recent changes proposed to the Nutrient Requirement System for Dairy Cattle in the US include variable efficiencies of absorbed essential AA for milk protein production. this first separation from a purely substrate-based system, standing on the old limiting AA theory, recognizes the abil.ty of the cow to alter the metabolism of AA. in this review we summarize a compelling amount of evidence suggesting that AA requirements for milk protein synthesis are based on a demand-driven system. Milk protein synthesis is governed at mammary level by a set of transduction pathways, including the mechanistic target of rapamycin complex 1(mtORC1), the integrated stress response(iSR), and the unfolded protein response(UPR). in tight coordination, these pathways not only control.the rate of milk protein synthesis, setting the demand for AA, but also manipul.te cellular AA transport and even blood flow to the mammary glands, securing the supply of those needed nutrients. these transduction pathways, specifically mtORC1, sense specific AA, as well as other physiological signals, including insulin, the canonical indicator of energy status. insulin plays a key role on mtORC1 signaling, controlling its activation, once AA have determined mtORC1 localization to the lysosomal *** on this molecular model, AA and insulin signals need to be tightly coordinated to maximize milk protein synthesis rate. the evidence in lactating dairy cows supports this model, in which insulin and glucogenic energy potentiate the effect of AA on milk protein synthesis. incorporating the effect of specific signaling AA and the differential role of energy sources on utilization of absorbed AA for milk protein synthesis seems like

关键词： Amino acids Blood flow insulin Mammary uptake Milk proteins mtORC1 Nitrogen efficiency Splanchnic tissues

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twenty years of popul.tion dynamics in European beech-oak forest at their rear range margin anticipate changes in its structure and composition

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Forest Ecosystems 2024年第3期11卷 358-370页

作者： álvaro Rubio-Cuadrado iciar Alberdi isabel Canellas Fernando Montes Jesús Rodríguez-Calcerrada Rosana lópez Guillermo G.Gordaliza María Valbuena-Carabana Nikos Nanos Ramón Perea luis Gil Departamento de dinamica y gestion forestal Instituto de Ciencias Forestales(ICIFOR-INIA)CSICCtra.La Coruna km 7.528040MadridSpain Departamento de Sistemas y Recursos Naturales Escuela Tecnica Superior de Ingeniería de MontesForestal y del Medio NaturalUniversidad Politecnica de Madrid.Ciudad Universitaria s/n28040MadridSpain School of Forestry and Natural Environment Aristotle University of ThessalonikiUniversity Campus54124ThessalonikiGreece

there is an increasing interest in restoring degraded forests,which occupy half of the forest *** the forms of restoration,passive restoration,which involves the elimination of degrading factors and the free evol.tion of natural dynamics by applying minimal or no management,is gaining *** dynamics is difficult to predict due to the influence of multiple interacting factors such as climatic and edaphic conditions,composition and abundance of species,and the successional character of these ***,we study the natural dynamics of a mixed forest located in central Spain,which maintained an open forest structure,due to intensive use,until grazing and cutting were banned in the *** most frequent woody species in this forest are Fagus sylvatica,Quercus petraea,Quercus pyrenaica,ilex aquifolium,Sorbus aucuparia,Sorbus aria and Prunus avium,with contrasting shade and drought *** species are common in temperate European deciduous forest and are found here near their southern distribution limit,except for *** order to analyze forest dynamics and composition,three inventories were carried out in 1994,2005 and *** results show that,despite the Mediterranean influence,the natural dynamics of this forest has been mainly determined by different levels of shade *** the abandonment of grazing and cutting,*** expanded rapidly due to its lower shade tolerance,whereas after canopy closure and forest densification,shade-tolerant species gained ground,particularly ***,despite its lower drought and l.te-frost *** the current dynamics continue,*** will overtake the rest of the species,which will be relegated to sites with shallow soils and steep ***,all.the multi-centennial beech trees,which are undergoing a rapid mortal.ty and decline process,will disappear.

关键词： Forest succession Secondary forest Woodland Mixed forest Competition Recruitment

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in situ laser deposition of Niti intermetallics for corrosion improvement of ti-6Al-4V alloy

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transactions of Nonferrous Metals Society of China 2015年第10期25卷 3315-3322页

作者： M.N.MOKGAlAKA A.P.i.POPOOlA S.l.PitYANA Department of Chemical Metallurgical and Materials EngineeringTshwane University of Technology Council for Scientific and industrial Research National Laser Centre

Niti intermetallic coatings were fabricated on the surface of ti-6Al-4V alloy by melting Ni and ti powders using laser metal deposition（lMD） *** effects of Niti reinforcement content on the microstructure,hardness and corrosion properties of the coatings were *** results show that the deposited coatings are characterized by Niti,Niti2 and Niti3 intermetallic *** appreciable increase in corrosion resistance is obtained for all.the coatings,and ti55Ni45 coating shows the highest corrosion resistance;while coatings ti50Ni50 and ti45Ni55 follow in that *** reinforcement materials are proven to be corrosion resistant in the tested environment,and the effect of ti is more dominant.

关键词： ti-6Al-4V alloy Niti intermetallic laser metal deposition corrosion behaviour

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Dual ecological and socio-cultural fragmentation induced by hydropower dams: Case studies from the Greater Himalayan region of india

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Zoological Research(Diversity and Conservation) 2024年第2期1卷 117-120页

作者： Garima Gupta Rahul Kotiyal isabel l.Jones Biological and Environmental Sciences University of StirlingScotland FK94LAUK Baramasa.in Narrating Himalaya 248001India

Climate change and biodiversity loss are pressing global challenges(Pörtner et al.,2021).However,as global energy demand continues to increase(iEA,2021),nations face significant challenges to decarbonization and reaching“net zero”due to trade-offs between the often-competing needs of renewable energy generation and biodiversity *** example,hydropower generates renewable energy(Gibson et al.,2017),yet there are well-documented and severe consequences of dam development for biodiversity(e.g.,Zarfl et al.,2019)and people(e.g.,Bisht,2009)due to reservoir creation and disruption of river *** such potentially damaging ecological and social.trade-offs,hydropower currently contributes 70%of global renewable energy and there are at least 3700 large dams planned or under construction globally(Zhang&Gu,2023).

关键词： reservoir consequences globally

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Numerical Modelling of the Aeroelastic Behaviour and Variable loads for the turbine Stage in 3D transonic Flow

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Journal of thermal Science 2005年第3期14卷 236-241页

作者： V.i. GNESiN l.V. KOlODYAZHNAYA R. RZADKOWSKi Department of Aerohydromechanics Institute of Mechanical Engineering Problems National Academy of Sciences of Ukraine 2/10 Pozharsky st. Kharkov 61046 Ukraine ProfessorDepartment of Aerohydromechanics Institute of Mechanical Engineering Problems National Academy of Sciences of Ukraine 2/10 Pozharsky st. Kharkov 61046 UkraineDepartment of Dynamics of Machines Institute of Fluid Flow Machinery Polish Academy of Sciences J. Fiszera st. 14 Gdansk 80 952 Poland

in this study presented the algorithm proposed involves the coupled sol.tion of 3-D unsteady flow through a turbine stage and the dynamics problem for rotor-blade motion by the action of aerodynamic forces, without separating the outer and inner flow fluctuations. the partially integrated method involves the sol.tion of the fluid and structural equations separately, but information is exchanged at each time step, so that sol.tion from one domain is used as a boundary condition for the other domain. 3-D transonic gas flow through the stator and rotor blades in rel.tive motion with periodicity on the whole annulus is described by the unsteady Euler conservation equations, which are integrated using the explicit monotonous finite-volume difference scheme of Godunov-Kolgan. the structural analysis uses the modal approach and a 3-D finite element model of a blade. A calcul.tion has been done for the last stage of the steam turbine, under design and off-design regimes. it is shown that the ampl.tude-frequency spectrum of blade oscill.tions contains the high frequency harmonics, corresponding to the rotor moving past one stator blade pitch, and low frequency harmonics caused by blade oscill.tions and flow nonuniformity downstream from the blade row; moreover, the spectrum involves the harmonics which are not multiples of the rotation frequency.

关键词： turbine stage 3D unsteady flow blade oscill.tions

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Non-polynomial Zig-Zag and ESl shear deformation theory to study advanced composites

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Chinese Journal of Aeronautics 2019年第4期32卷 906-920页

作者： J.l.MANtARi i.A.RAMOS J.C.MONGE Faculty of Mechanical Engineering Instituto de investigación en ingeniería naval(IDIIN)National University of Engineering(UNI)Lima 15333Peru Department of Mechanical Engineering University of New Mexico Faculty of Mechanical Engineering Universidad de Ingeniería y Tecnología(UTEC)

the mechanical behavior of advanced composites can be modeled mathematically through unknown variables and Shear Strain thickness Functions(SStFs). Such SStFs can be of polynomial or non-polynomial nature and some parameters of non-polynomial SStFs can be optimized to get optimal results. in this paper, these parameters are called ‘‘r" and ‘‘s" and they are the argument of the trigonometric SStFs introduced within the Carrera Unified Formul.tion(CUF). the Equivalent Single layer(ESl) governing equations are obtained by employing the Principle of Virtual Displacement(PVD) and are solved using Navier method sol.tion. Furthermore, trigonometric expansion with Murakami theory was implemented in order to reproduce the Zig-Zag effects which are important for multilayer structures. Several combinations of optimization parameters are evaluated and selected by different criteria of average error. Results of the present unified trigonometrical.theory with CUF bases confirm that it is possible to improve the stress and displacement results through the thickness distribution of models with reduced unknown variables. Since the idea is to find a theory with reduced numbers of unknowns, the present method appears to be an appropriate technique to select a simple model. However these optimization parameters depend on the pl.te geometry and the order of expansion or unknown variables. So, the topic deserves further research.

关键词： Anal.tical sol.tion Composite materials CUF ESl Pl.te trigonometric functions Zig-Zag effects

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Novel kinetic model for the simul.tion analysis of the butanol productivity of Clostridium acetobutylicum AtCC 824 under different reactor configurations

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Chinese Journal of Chemical Engineering 2018年第4期26卷 812-821页

作者： Hugo i.Velázquez-Sánchez Ricardo Aguilar-lópez Center of Research and Advances Studies of the National Pol.technic institute (CiNVEStAV) Biotechnology and Bioengineering DepartmentAv. National Polytechnic Institute 2508 Col. San Pedro Zacatenco

Acetone–butanol–ethanol(ABE)fermentation process can be exploited for the generation of butanol as biofuel,however it does need to overcome its low volumetric solvent productivity before it can commercially compete with fossil fuel *** this regard,mathematical modelling and simul.tion analysis are tools that can serve as the base for process engineering development of biological *** this work,a novel phenomenological kinetic model of Clostridium acetobutylicum AtCC 824 was considered as a benchmark system to evaluate the behaviour of an ABE fermentation under different process configurations using both free and immobilized cells:single stage batch operation,fed-batch,single stage Continuous Stirred tank Reactor(CStR)and multistage CStRs with and without biomass *** proposed model achieved a linear correl.tion index r^2=0.9952 and r^2=0.9710 over experimental data for free and immobilized cells *** predicted maximum butanol concentration and productivity obtained were 13.08 g·l^(-1)and 1.9620 g·l^(-1)·h^(-1)respectively,which represents an increase of 1.01%and 990%versus the currently developed industrial scale process reported currently into the *** results provide a reliable pl.tform for the design and optimization of the ABE fermentation system and showcase the adequate predictive nature of the proposed model.

关键词： Biofuels Butanol Clostridium acetobutylicum Mathematical modelling Process configurations

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Crystallization and impact history of a meteoritic sample of early lunar crust(NWA 3163)refined by atom probe geochronology

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Geoscience Frontiers 2019年第5期10卷 1841-1848页

作者： l.F. White D.E. Moser K.t. tait B. langelier i. Barker J.R. Darling Centre for Applied Planetary Mineralogy Department of Natural HistoryRoyal Ontario MuseumTorontoOntarioM5S 2C6Canada Department of Earth Sciences University of TorontoTorontoOntarioM5S 3B1Canada Department of Earth Sciences University of Western OntarioLondonN6A 5B7Canada Canadian Centre for Electron Microscopy McMaster UniversityHamiltonOntarioCanada School of Earth and Environmental Science University of PortsmouthPortsmouthUK

Granul.tic lunar meteorites offer rare insights into the timing and nature of igneous,metamorphic and impact processes in the lunar *** dating the different events recorded by these materials is very challenging,however,due to low trace element abundances (***,Nd,lu,Hf),rare micrometerscale U-th-bearing accessory minerals,and disturbed Ar-Ar systematics following a multi-stage history of shock and thermal *** we report on micro-baddeleyite grains in granul.tic mafic breccia NWA 3163 for the first time and show that targeted microstructural analysis (electron backscatter diffraction) and nanoscale geochronology (atom probe tomography) can overcome these barriers to lunar chronology.A twinned (-90°/) baddeleyite domain yields a 232th/208Pb age of 4328 ± 309 Ma,which overlaps with a robust secondary ion mass spectrometry (SiMS) 207Pb/206Pb age of 4308± 18.6 Ma and is interpreted here as the crystallization age for the igneous protol.th of NWA 3163.A second microstructural domain,in width,contains patchy overprinting baddeleyite and yields a th-Pb age of 2175± 143 Ma,interpreted as dating the last substantial impact event to affect the *** finding demonstrates the potential of combining microstructural characterization with nanoscale geochronology when resolving complex P-t-t histories in planetary materials,here yielding the oldest measured crystallization age for components of lunar granul.te NWA 3163 and placing further constraints on the formation and evol.tion of lunar crust.

关键词： Baddeleyite U-th-Pb isotopes EBSD Atom probe tomography Geochronology Northwest Africa 3163

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^(13)C NMR and structural study of solid state naphthol-1 and naphthol-2 arylazo-derivatives

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Chinese Journal of Chemistry 1991年第3期9卷 245-250页

作者： FEDOROV l.A. REBROV A.i. REBROV A.i. institute of Geochemistry and Anal.tical Chemistry Academy of Sciences of USSR Institute of Geochemistry and Analytical ChemistryAcademy of Sciences of USSR

Solid state ^(13)C NMR spectra of a series of naphthol-1 and naphthol-2-arylazo--deriva- tives were studied and compared with respective results in *** of carbon nuclei of naphthalene ring were *** forms of compounds were *** was shown that 4-(p-NO_2C_6H_4)-azonaphthol-1 and 1-(p-NO_2C_6H_4)-azonaphthol-2 in solid state existed ex- clusively in quinohydrazone *** other two compounds——1-(C_6F_5)-azonaphthol-2 and 2-(p- CH_3C_6H_4)-azonaphthol-1 in solid state were not found in the form of individual.tautomeric mixtures but in respective tautomeric equilibrium ***,during transition from liquid to solid state, the tautomeric equilibrium was practically *** solid state it was found that rotation around aryl-N bond was hindered in the time scale of NMR spectroscopy.

关键词： C NMR and structural study of solid state naphthol-1 and naphthol-2 arylazo-derivatives NMR

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Percutaneous radiofrequency abl.tion for early hepatocellular carcinoma: Risk factors for survival

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World Journal of Gastroenterology 2014年第6期20卷 1585-1593页

作者： luciana Kikuchi Marcos Menezes Aline l Chagas Claudia M tani Regiane SSM Alencar Marcio A diniz Venncio AF Alves luiz Augusto Carneiro D’Albuquerque Flair José Carrilho So Paulo Clínicas liver Cancer Group Instituto do Cancer do Estado de So Paulo Hospital das Clínicas Department of Gastroenterology University of So Paulo School of Medicine So Paulo Clínicas liver Cancer Group Instituto do Cancer do Estado de So Paulo Hospital das Clínicas Department of Radiology University of So Paulo School of Medicine So Paulo Clínicas liver Cancer Group Instituto do Cancer do Estado de So Paulo Hospital das Clínicas Department of Pathology University of So Paulo School of Medicine

AiM: to evaluate outcomes of radiofrequency abl.tion (RFA) therapy for early hepatocellular carcinoma (HCC) and identify survival- and recurrence-rel.ted factors.

关键词： Hepatocellular carcinoma Radiofrequency abl.tion Overall survival Disease-free survival

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