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Relationship between angiotensin-(1-7) and angiotensin Ⅱ correlates with hemodynamic changes in human liver cirrhosis

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World Journal of Gastroenterology 2009年第20期15卷 2512-2519页

作者： Walkíria Wingester Vilas-Boas Antnio ribeiro-Oliveira Jr Regina Maria Pereira renata da cunha ribeiro Jerusa Almeida Ana Paula Nadu Ana Cristina Simoes e Silva Robson Augusto Souza dos Santos Laboratory of Hypertension Department of Physiology Biological Sciences institute Federal University of Minas Gerais Av. Antonio Carlos 6627 Belo Horizonte MG 31270-901 Brazil Laboratory of Endocrinology Department of Medicine Faculty of Medicine Federal University of Minas Gerais Av. Alfredo Balena 190 Belo Horizonte MG 30130-100 Brazil Hospitalar Foundation of the State of Minas Gerais FHEMIG Belo Horizonte MG Brazil Department of Pediatrics Faculty of Medicine Federal University of Minas Gerais Av.Alfredo Balena 190 Belo Horizonte MG 30130-100 Brazil

AIM:To measure circulating angiotensins at different stages ofhuman cirrhosis and to further evaluate a possible relationship between renin angiotensin system (RAS) components and hemodynamic ***: Patients were allocated into 4 groups: mild-to-moderate liver disease (MLD), advanced liver disease (ALD), patients undergoing liver transplantation, and healthy controls. Blood was collected to determine plasma renin activity (PRA), angiotensin (Ang) , Ang Ⅱ, and Ang-(1-7) levels using radioimmunoassays. During liver transplantation, hemodynamic parameters were determined and blood was simultaneously obtained from the portal vein and radial artery in order to measure RAS ***: PRA and angiotensins were elevated in ALD when compared to MLD and controls (P < 0.05). In contrast, Ang was signicantly reduced in MLD. Ang-(1-7)/Ang Ⅱ ratios were increased in MLD when compared to controls and ALD. During transplantation, Ang Ⅱ levels were lower and Ang-(1-7)/Ang Ⅱ ratios were higher in the splanchnic circulation than in the peripheral circulation (0.52 ± 0.08 vs 0.38 ± 0.04, P < 0.02), whereas the peripheral circulating Ang /Ang ratio was elevated in comparison to splanchnic lev-els (0.18 ± 0.02 vs 0.13 ± 0.02, P < 0.04). Ang-(1-7)/Ang Ⅱ ratios positively correlated with cardiac output (r= 0.66) and negatively correlated with systemic vascular resistance (r =-0.70).CONCLUSION: Our ndings suggest that the relation-ship between Ang-(1-7) and Ang Ⅱmay play a role in the hemodynamic changes ofhuman cirrhosis.

关键词：血管紧张素血流动力学肝硬化人类

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Could mammalian inorganic polyphosphate be a crucial signaling molecule in neurological disorders?

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Neural Regeneration Research 2024年第4期19卷 701-702页

作者： renata Torres da Costa Maria E.Solesio Rutgers University Department of BiologyCamdenNJUSA

Since the early stages of life on earth,cellular metabolism has evolved to adapt to fluctuations in nutrient and oxygen *** this context,mammals,which are probably the organisms that show one of the highest levels of metabolic complexity,have developed an elegant system that uses constant and rechargeable energy sources of modulate their *** homeostasis is especially important in the central nervous system,as neurons and other cells in the brain are highly susceptible to fluctuations in nutrients and oxygen availability.

关键词： metabolism homeostasis neurological

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Effect of propranolol on the splanchnic and peripheral renin angiotensin system in cirrhotic patients

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World Journal of Gastroenterology 2008年第44期14卷 6824-6830页

作者： Walkíria Wingester Vilas-Boas Antnio ribeiro-Oliveira Jr renata da cunha ribeiro renata Lúcia Pereira Vieira Jerusa Almeida Ana Paula Nadu Ana Cristina Sim■es e Silva Robson Augusto Souza Santos Laboratório de Hipertenso Departamento de Fisiologia e BiofísicaICB-UFMGAv. Antonio Carlos6627Belo HorizonteMG31270-901Brazil Laboratório de Endocrinologia Departamento de Clínica MédicaFaculdade de Medicina-UFMGAv. Alfredo Balena190Belo HorizonteMG30130-100Brazil Departamento de Pediatria Faculdade de MedicinaUniversidade Federal de Minas Gerais (UFMG)Av. Alfredo Balena190Belo HorizonteMG30130-100Brazil

AIM:To evaluate the effect of β-blockade on angiotensins in the splanchnic and peripheral circulation of cirrhotic patients and also to compare hemodynamic parameters during liver transplantation according to propranolol pre-treatment or not. METHODS:Patients were allocated into two groups:outpatients with advanced liver disease(LD) and during liver transplantation(LT). Both groups were subdivided according to treatment with propranolol or not. Plasma was collected through peripheral venipuncture to determine plasma renin activity(PRA),Angiotensin(Ang) Ⅰ,Ang Ⅱ,and Ang-(1-7) levels by radioimmunoassay in LD group. During liver transplantation,hemodynamic parameters were determined and blood samples were obtained from the portal vein to measure renin angiotensin system(RAS) ***:PRA,Ang Ⅰ,Ang Ⅱ and Ang-(1-7) were signifi cantly lower in the portal vein and periphery in all subgroups treated with propranolol as compared to non-treated. The relationships between Ang-(1-7) and Ang Ⅰ levels and between Ang Ⅱ and Ang Ⅰ were significantly increased in LD group receiving propranolol. The ratio between Ang-(1-7) and Ang Ⅱ remained unchanged in splanchnic and peripheral circulation in patients under β-blockade,whereas the relationship between Ang Ⅱ and Ang Ⅰ was significantly increased in splanchnic circulation of LT patients treated with propranolol. During liver transplantation,cardiac output and index as well systemic vascular resistance and index were reduced in propranolol-treated subgroup. CONCLUSION:In LD group,propranolol treatment reduced RAS mediators,but did not change the ratio between Ang-(1-7) and Ang Ⅱ in splanchnic and peripheral circulation. Furthermore,the modification of hemodynamic parameters in propranolol treated patients was not associated with changes in the angiotensin ratio.

关键词： β阻塞内脏血管紧张素肾素

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Plant growth and metabolism of exotic and native Crotalaria species for mine land rehabilitation in the Amazon

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Journal of Forestry Research 2024年第1期35卷 143-154页

作者： Hemelyn Soares das Chagas Rafael Silva Guedes Markus Gastauer Paula Godinho ribeiro Allan Klynger da Silva Lobato Cecílio Frois Caldeira Fabrício William deÁvila AndréRodrigues dos Reis Silvio Junio Ramos Instituto Tecnológico Vale Rua Boaventura da Silva955BelémPA 66055-090Brazil Universidade Federal do Sul e Sudeste do Pará XinguaraPABrazil Núcleo de Pesquisa Vegetal Básica e Aplicada Universidade Federal Rural da AmazôniaParagominasPABrazil Departamento de Engenharia Florestal Universidade Estadual do Centro-Oeste/UNICENTROIratiPRBrazil School of Sciences and Engineering São Paulo State University(UNESP)TupãSP.CEP 17602-496Brazil

Despite its enormous benefits,mining is respon-sible for intense changes to vegetation and soil ***,after extraction,it is necessary to rehabilitate the mined areas,creating better conditions for the establishment of plant species which is *** study evaluated mineral and organic fertilization on the growth,and carbon and nitrogen(N)metabolism of two Crotalaria species[Cro-talaria spectabilis(exotic species)and Crotalaria maypu-rensis(native species from Carajás Mineral Province(CMP)]established on a waste pile from an iron mine in CMP.A control(without fertilizer application)and six fertilization mixtures were tested(i=NPK;ii=NPK+micronutrients;iii=NPK+micronutrients+organic compost;iv=PK;v=PK+micronutrients;vi=PK+micronutrients+organic compost).Fertilization contributed to increased growth of both species,and treatments with NPK and micronutrients had the best results(up to 257%***),while organic fertilization did not show *** Crotalaria had a greater number of nodules,higher nodule dry mass,chlorophyll a and b contents and showed free ammonium as the predominant N form,reflecting greater increments in biomass compared to native *** having lower growth,the use of this native species in the rehabilitation of mining areas should be considered,mainly because it has good development and meets current government legislation as an opportunity to restore local biodiversity.

关键词： Biological nitrogen fixation Mining Nitrogen metabolism Plant nutrition

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Study on 6-DOF active vibration-isolation system of the ultra-precision turning lathe based on GA-BP-PID control for dynamic loads

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Advances in Manufacturing 2024年第1期12卷 33-60页

作者： Bo Wang Zhong Jiang Pei-da Hu Department of Precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining *** active vibration-isolation systems(AVIS)have been developed based on static *** a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy *** solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining ***-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were *** experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load *** design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation Six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control

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Impact Containment Barriers with Geotextile Tubes

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Journal of Geoscience and Environment Protection 2024年第5期12卷 325-344页

作者： Flávio da Silva Ornelas Luís Fernando Martins ribeiro Rafael Cerqueira Silva Instituto Federal de Educaç &#227o Ci&#234ncia e Tecnologia&#8212IFTO Palmas Brasil Departamento de Engenharia Civil e Ambiental Programa de p&#243s gradua&#231&#227o em Geotecnia Universidade de Bras&#237lia&#8212UnB/Campus Universit&#225rio Darcy Ribeiro Bras&#237lia Brasil

Recently, tragic tailings dam collapses in Brazil have caused deaths and major destruction and the need to develop technologies capable of preventing damage to people and the environment. Brazilian tailings dams are in a situation of uncertainty due to new legislation that even requires decommissioning, an activity that involves many problems and where the risk of failure is the main one. An impact containment structure downstream of these dams can be effective and geotextile tubes, in a new approach, have emerged as an option with advantages in terms of execution, costs and safety. The technology is versatile and can bring many benefits such as the reuse of tailings or filling with low-energy or reused materials. In this research, geotextile tubes were tested as free containment barriers, experiencing impacts in reduced models. The safety factor for the stability of the structure was constructed using an equation which is the ratio between the self-weight of the barrier structure and its coefficient of static friction and the impact pressure, where the data showed an adequate correlation which suggests the viability of mitigating risks.

关键词： Geotextile Tube Debris Flow Barriers Impact Mining

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On entire solutions of some Fermat type differential-difference equations

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 69-88页

作者： LONG Jian-ren QIN da-zhuan School of Mathematical Sciences Guizhou Normal UniversityGuiyang 550025China

On one hand,we study the existence of transcendental entire solutions with finite order of the Fermat type difference *** the other hand,we also investigate the existence and growth of solutions of nonlinear different... 详细信息

关键词： entire solutions differential-difference equations existence finite order

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On the global smooth solutions of 3D incompressible Hall-MHD equations

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 319-327页

作者： YUE Gao-cheng SUN Wen-da School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106China

The present paper is devoted to the well-posedness issue for the 3D incompressible Hall-MHD system obtained from kinetic models. Our analysis strongly relies on the use of the Fourier analysis. We establish the global existence of smooth solutions for a class of large initial data, this result implies the initial velocity and magnetic field can be arbitrarily large.

关键词： 3D Hall-MHD well-posedness Fourier analysis

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Quantized bound states around a vortex in anisotropic superconductors

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 146-155页

作者： Ke Xiang da Wang Qiang-Hua Wang National Laboratory of Solid State Microstructures&School of Physics Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

The bound states around a vortex in anisotropic superconductors is a longstanding yet important *** this work,we develop a variational theory on the basis of the Andreev approximation to obtain the energy levels and wave functions of the low-energy quantized bound states in superconductors with anisotropic pairing on arbitrary Fermi *** the case of circular Fermi surface,the effective Schr¨odinger equation yielding the bound state energies gets back to the theory proposed by Volovik and Kopnin many years *** generalization here enables us to prove the equidistant energy spectrum inside a vortex in a broader class of *** importantly,we are now able to obtain the wave functions of these bound states by projecting the quasiclassical wave function on the eigenmodes of the effective Schr¨odinger equation,going beyond the quasiclassical Eilenberger results,which,as we find,are sensitive to the scattering *** the case of isotropic Fermi surface,the spatial profile of the low-energy local density of states is dominated near the vortex center and elongates along the gap antinode directions,in addition to the ubiquitous Friedel oscillation arising from the quantum inteference neglected in the Eilenberger ***,as a consequence of the pairing anisotropy,the quantized wave functions develop a peculiar distribution of winding number,which reduces stepwise towards the vortex *** work provides a flexible way to study the vortex bound states in the future.

关键词： vortex bound state anisotropic superconductor Andreev approximation

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Small-scale self-driving cars:A systematic literature review

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 271-292页

作者： Felipe Caleffi Lauren da Silva Rodrigues Joice da Silva Stamboroski Brenda Medeiros Pereira Autonomous Vehicles Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil Mobility and Logistics Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil

The autonomous vehicle(AV)technology has the potential to significantly improve safety and efficiency of the transportation and logistics ***-scale AV testing is limited by time,space,and cost,while simulation-based testing often lacks the necessary accuracy of AV and environmental *** recent years,several initiatives have emerged to test autonomous software and hardware on scaled *** systematic literature review provides an overview of the literature surrounding small-scale self-driving cars,summarizing the current autonomous platforms deployed and focusing on the software and hardware developments in this *** studies published in English-language journals or conference papers that present small-scale testing of self-driving cars were *** of Science,Scopus,Springer Link,Wiley,ACM Digital Library,and TRID databases were used for the literature *** systematic literature search found 38 eligible *** gaps in the reviewed papers were identified to provide guidance for future *** key takeaway emerging from this manuscript are:(i)there is a need to improve the models and neural network architectures used in autonomous driving systems,as most papers present only preliminary results;(ii)increasing datasets and sharing databases can help in developing more reliable control policies and reducing bias and variance in the training process;(iii)small-scaled vehicles to ensure safety is a major benefit,and incorporating data about unsafe driving behaviors and infrastructure problems can improve the accuracy of predictive models.

关键词： Self-driving car Autonomous vehicle Small-scale vehicle Systematic literature review

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