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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

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

Local Hamilton type Gradient Estimates and Harnack Inequalities for Nonlinear Parabolic Equations on Riemannian manifolds

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Acta mathematicae Applicatae Sinica 2024年第2期40卷 539-546页

作者： Wen WANG da-peng XIE Hui ZHOU School of mathematics and Statistics Hefei Normal UniversityHefei 230601China

In this paper,we prove a local Hamilton type gradient estimate for positive solution of the nonlinear parabolic equation ut(x,t)=Δu(x,t)+au(x,t) ln u(x,t)+bu^(α)(x,t),on m×(-∞,∞) with α∈R,where a and b are *** ... 详细信息

关键词： nonlinear parabolic equation gradient estimate Harnack inequality

Extracellular vesicles-coupled miRNAs from oviduct and uterus modulate signaling pathways related to lipid metabolism and bovine early embryo development

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1528-1549页

作者： Rosane mazzarella Karina Canon‑Beltran Yulia N.Cajas meriem Hamdi Encina m.Gonzalez Juliano C.da Silveira Claudia L.V.Leal D.Rizos Department of Animal Reproduction INIA-CSICMadridSpain Department of Biochemistry and molecular Biology Veterinary FacultyComplutense University of Madrid(UCM)MadridSpain Department Agrarian Production Technical University of MadridUPMMadridSpain Departamento de Ciencias Biologicas Universidad Tecnica Particular de LojaUTPLLojaEcuador Department of Anatomy and Embryology FV-UCMMadridSpain Department of Veterinary medicine FZEA-USPPirassunungaBrazil

Background Extracellular vesicles(EVs) present in oviductal(OF) and uterine fluid(UF) have been shown to enhance bovine embryo quality during in vitro culture by reducing lipid contents and modulating lipid metabolism-related genes(LmGs), while also influencing cell proliferation, suggesting their involvement on the regulation of different biological pathways. The regulation of signaling pathways related to cell differentiation, proliferation, and metabo-lism is crucial for early embryo development and can determine the success or failure of the pregnancy. Bioactive molecules within EVs in maternal reproductive fluids, such as micro RNAs(miRNAs), may contribute to this regulatory process as they modulate gene expression through post-transcriptional *** This study evaluated miRNA cargo in OF-EVs from the early luteal phase and UF-EVs from the mid-luteal phase, coinciding with embryo transit within oviduct and uterus in vivo, and its possible influence on LmGs and sign-aling pathways crucial for early embryo development. A total of 333 miRNAs were detected, with 11 exclusive to OF, 59 to UF, and 263 were common between both groups. From the 20 differentially expressed miRNAs, 19 up-regulated in UF-EVs(bta-miR-134, bta-miR-151-3p, bta-miR-155, bta-miR-188, bta-miR-181b, bta-miR-181d, bta-miR-224, bta-miR-23b-3p, bta-miR-24-3p, bta-miR-27a-3p, bta-miR-29a, bta-miR-324, bta-miR-326, bta-miR-345-3p, bta-miR-410, bta-miR-652, bta-miR-677, bta-miR-873 and bta-miR-708) and one(bta-miR-148b) in OF-EVs. These miRNAs were predicted to modulate several pathways such as Wnt, Hippo, mAPK, and lipid metabolism and degradation. Differ-ences in miRNAs found in OF-EVs from the early luteal phase and UF-EVs from mid-luteal phase may reflect differ-ent environments to meet the changing needs of the embryo. Additionally, miRNAs may be involved, particularly in the uterus, in the regulation of embryo lipid metabolism, immune system, and *** Our study su

关键词： Embryo-maternal interaction Epigenetic Exosomes mammalian Preimplantation Reproductive fluids

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.Sardar m.D.Hossain m.S.Sikder m.N.I.Khan m.R.Rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofComputer Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh material Science Division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEm),energy dispersive X-ray(EDX),vibrating sample magnetometer(VSm),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEm images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

The first record of a Konservat-Lagerstätten in which early post-settlement stages of fossil archaeobalanids(Cirripedia:Balanomorpha)are preserved

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Integrative Zoology 2024年第2期19卷 200-223页

作者： Tomáš KOCÍ Rok gaŠPARIC John BUCKERidGE martina KOCOVÁ VESELSKÁ Aleš ŠOSTER Ivancická581 PragueCzech Republic Palaeontological Department Natural History MuseumNational MuseumPragueCzech Republic Oertijdmuseum Bosscheweg 80Boxtel5293 WBThe Netherlands Institute for Palaeobiology and Evolution Novi TrgKamnikSlovenia Earth and Oceanic Systems Group RMIT UniversityMelbourneAustralia museums Victoria CarltonVictoriaAustralia Department of Paleobiology and Paleoecology Institute of Geology of the Czech Academy of SciencesPragueCzech Republic Institute of Geology and Palaeontology Charles UniversityPragueCzech Republic Faculty of Natural Sciences and Engineering University of LjubljanaLjubljanaSlovenia

A diverse sessile barnacle fauna from a miocene shallow-water deposit at Dolnja Stara vas in Slovenia is *** includes the first descriptions of early post settlement juveniles of Actinobalanus sloveniensis attached to mangrove *** represent three distinct growth phases,the earliest being interpreted as being less than 24 h post settlement,the others being 1 to 2 days post *** assessment of their taphonomy is *** adult balanomorphs are attached to a variety of organic substrates,including mangrove leaves and branches,fragments of the conifers?Taxodioxylon,Carapoxylon,pine cones,molluscs,and cetacean *** barnacles include ***,Amphibalanus venustus,and Perforatus perforatus—many with opercula retained within the *** retains some of the original shell *** is the second record of barnacle–plant associations from the Central Paratethys from Kamnik and *** paleoecology and paleogeography of the site are discussed.

关键词： acorn barnacles barnacle metamorphosis epibiont paleoecology taxonomy

Study of Harmful Vaginal Practices of Women in the municipality of Ouagadougou, Burkina Faso

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Health 2024年第5期16卷 425-438页

作者： daniel Dori Ramata Porgo Hyacinthe Zamané Nicolas méda Rasmané Semdé Drug Development Laboratory African Center of Excellence for Training Research and Expertise in Pharmaceutical Sciences (CEA-CFOREM) Sciences and Health Doctoral School Training and Research Unit in Health Sciences Joseph Ki-Zerbo University Ouagadougou Burkina Faso Charles De gaulle University Children’ s Hospital (CHUP-CDG) Ouagadougou Burkina Faso Public Health Laboratory Sciences and Health Doctoral School Joseph Ki-Zerbo University Ouagadougou Burkina Faso mother and Child Laboratory Sciences and Health Doctoral School Joseph Ki-Zerbo University Ouagadougou Burkina Faso

Introduction: Vaginal practices include washing, altering, cutting, cleaning, enhancing, drying, tightening, lubricating, or loosening of the vagina, labia, clitoris, or hymen. This study aimed to investigate the different vaginal practices of women using non-pharmaceutical products. methodology: This was a cross-sectional study with descriptive and analytical purposes that took place from January 15 to April 23, 2023, in the four largest markets in the municipality of Ouagadougou. This was performed using the data collection sheet in the KoboCollect application. Epi info 7.***.5.0. software was used for data analysis. For the analysis of associated factors, a p-value Results: In total, 977 women were surveyed. Among them, 43.19% underwent vaginal procedures using non-pharmaceutical products. The female practitioners were 34.34 ± 7.44 years old. The products used included plants, mineral substances, ointments, tablets, and solutions. Among the practicing women, 40.99% were looking for vaginal tightening. The main purpose was to maintain their partners (45.97%). Three-point thirty-two percent (3.32%) of the women who underwent vaginal procedures had reported adverse events. Conclusion: Raising awareness of the consequences of vaginal practices and encouraging women to go to a health center for any gynecological problem could significantly reduce the prevalence of vaginal practices.

关键词： Vaginal Practices Women Adverse Events Products

Study of the management and Disposal Practices of Unused or Out-of-date medicines by Households in the municipality of Ouagadougou, Burkina Faso

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Journal of Biosciences and medicines 2024年第3期12卷 291-302页

作者： daniel Dori Adama Guembré Kampadilemba Ouoba Nicolas méda Rasmané Semdé Drug Development Laboratory African Center of Excellence for Training Research and Expertise in Pharmaceutical Sciences (CEA-CFOREM) Sciences and Health Doctoral School Training and Research Unit in Health Sciences Joseph KI-ZERBO University Ouagadougou Burkina Faso Charles De gaulle University Children's Hospital (CHUP-CDG) Ouagadougou Burkina Faso National Agency for Pharmaceutical Regulation (ANRP) Ministry of Health Ouagadougou Burkina Faso Public Health Laboratory Sciences and Health Doctoral School Joseph KI-ZERBO University Ouagadougou Burkina Faso

Introduction: Not all medicines that pass-through consumers’ hands are used, and some often expire in households. These health products can be sources of accidental risks and pollution when they are not properly disposed of. In Burkina Faso, there are as yet no guidelines for the disposal of unused medicines in households. The aim of this study was to estimate the extent of household possession of unused or expired medicines, and to describe attitudes and disposal practices. methods: This was a descriptive cross-sectional study covering households in the Ouagadougou commune conducted from June to August 2021. Two-stage stratified sampling was used: selection of Enumeration Zones (EZs) and selection of households, with each EZ comprising several households. data collection was based on direct interviews using a structured questionnaire. data were processed using Epi Info software version 7.***.4.0. Results: In total, 417 household residents were surveyed out of the planned 423 households, corresponding to a completion rate of 98.58% compared with the initial sample. Among the respondents, 79.62% had unused and/or expired medicines in their household. A total of 2562 drug packaging units were counted, for a total weight of 121.90 kg. Nearly 75% were aware that improper disposal was a danger to the environment. Some respondents kept their unused medicines at home until they expired (43.41%), and disposed of them mainly by throwing them in the household garbage (75.58%). The majority (79%) were in favor of the government setting up a take-back program for these medicines. Conclusion: The introduction of a take-back program for unused or out-of-date medicines will ensure safer disposal of medicines, and better protection for households and the environment.

关键词： Unused medicines Expired medicines Disposal Household Risk

molecular and cellular mechanisms of neuroprotection by oligopeptides from snake venoms

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BIOCELL 2024年第6期48卷 897-904页

作者： CARLOS ALBERTO-SILVA BRENda RUFINO da SILVA Natural and Humanities Sciences Center Experimental Morphophysiology LaboratoryFederal University of ABC(UFABC)São Bernardo do CampoSão PauloBrazil

Venom snake-derived peptides have multiple biochemical,pharmacological,and toxicological proﬁles,allowing for the discovery of new medicinal products and therapeutic *** review speciﬁcally examines the fundamental elements of neuroprotection offered by different oligopeptides derived from snake *** also includes a brief evaluation of short peptides that are being considered as potential therapeutic ***-rich peptides and tryptophyllin family peptides isolated from the crude venom of Viperidae family snakes,speciﬁcally Bothrops atrox,Bothrops jararaca,and Bothrops moojeni,have been shown to have pro-survival properties,the ability to reduce oxidative stress,and the ability to promote cell viability and mitochondrial *** signiﬁcant mechanisms are related to the neuroprotection mediated by snake venom oligopeptides:(1)Activation of the L-arginine metabolite pathway,such as polyamines from ornithine metabolism,which reduces N-methyl-D-aspartate(Nmda)-type glutamate receptor activity;(2)Enhancement of cell viability by activating the nerve growth factor-signaling pathway;and(3)Activation of the muscarinic acetylcholine receptor subtype m1(mAChR-m1).These small peptides show promise as neuroprotective agents against a variety of neurodegenerative disorders.

关键词： Neuroprotective peptides Neurodegenerative disease Oxidative stress Reactive oxygen species Biopeptides

Rheological and stability analysis of cement pastes incorporating silica-based wastes

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Particuology 2024年第6期89卷 144-152页

作者： Julia da Rosa martins Janaíde Cavalcante Rocha dachamir Hotza Luciano Senff Graduate Program in materials Science and Engineering(PPGmAT) Federal University of Santa Catarina(UFSC)Florianópolis88040-900SCBrazil Graduate Program in Civil Engineering(PPGEC) Federal University of Santa Catarina(UFSC)Florianópolis88040-900SCBrazil Graduate Program in Chemical Engineering(POSENQ) Federal University of Santa Catarina(UFSC)Florianópolis88040-900SCBrazil Department of mobility Engineering Federal University of Santa Catarina(UFSC)Joinville89219-600SCBrazil

This study investigates the influence of waste characteristics,especially zeta potential,on the properties of cement pastes and *** focus is to evaluate the impact of the zeta potential of cement particles and waste materials on the sedimentation speed,rheology,and hardening time of stabilized cement *** Cement II F 40,retarder additive,silica,and fly ash were used in the *** pastes were prepared,and during the stabilization period,their rheological properties and pH were *** zeta potential and sedimentation speed of the cement and waste particles were measured at the pH that the pastes presented during the entire stabilization *** the stabilization period,the pastes were subjected to the hardening time *** zeta potential analyses revealed diverse values for the different powder types,with the cement particles exhibiting a zeta potential of−3.0 mV,the silica particles exhibiting−10.5 mV,and the fly ash particles exhibiting−20.3 *** influence of the high zeta potential modulus was observed on the sedimentation speed,with the solution containing fly ash exhibiting a speed of 40.01μm/s,whereas the solution containing only cement exhibited a speed of 99.38μm/*** the pastes,the results indicate that the presence of fly ash particles with a significantly negative zeta potential led to a 16%reduction in hardening time compared to particles with a lower modulus of zeta *** tests showed that the inclusion of fly ash particles prevented the formation of *** the zeta potential influenced agglomerate formation and hardening time,it was found to have no effect on yield stress or viscosity.

关键词： Wastes Zeta potential Setting time Rheometry