检索结果-南通市图书馆

How do neurons age?A focused review on the aging of the microtubular cytoskeleton

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural regeneration research 2024年第9期19卷 1899-1907页

作者： Brad richardson Thomas Goedert Shmma Quraishe Katrin Deinhardt Amritpal Mudher School of Biological Sciences University of SouthamptonSouthamptonUK Institute of Developmental and regenerative Medicine University of OxfordOxfordUK

Aging is the leading risk factor for Alzheimer’s disease and other neurodegenerative diseases. We now understand that a breakdown in the neuronal cytoskeleton, mainly underpinned by protein modifications leading to the destabilization of microtubules, is central to the pathogenesis of Alzheimer’s disease. This is accompanied by morphological defects across the somatodendritic compartment, axon, and synapse. However, knowledge of what occurs to the microtubule cytoskeleton and morphology of the neuron during physiological aging is comparatively poor. Several recent studies have suggested that there is an age-related increase in the phosphorylation of the key microtubule stabilizing protein tau, a modification, which is known to destabilize the cytoskeleton in Alzheimer’s disease. This indicates that the cytoskeleton and potentially other neuronal structures reliant on the cytoskeleton become functionally compromised during normal physiological aging. The current literature shows age-related reductions in synaptic spine density and shifts in synaptic spine conformation which might explain age-related synaptic functional deficits. However, knowledge of what occurs to the microtubular and actin cytoskeleton, with increasing age is extremely limited. When considering the somatodendritic compartment, a regression in dendrites and loss of dendritic length and volume is reported whilst a reduction in soma volume/size is often seen. However, research into cytoskeletal change is limited to a handful of studies demonstrating reductions in and mislocalizations of microtubule-associated proteins with just one study directly exploring the integrity of the microtubules. In the axon, an increase in axonal diameter and age-related appearance of swellings is reported but like the dendrites, just one study investigates the microtubules directly with others reporting loss or mislocalization of microtubule-associated proteins. Though these are the general trends reported, there are clea

关键词： age-related changes aging cytoskeleton microtubules neuronal morphology

维普期刊数据库

Hydrocarbon indication in rio Bonito Formation sandstone:Implication for cO_(2)storage in São Paulo,Brazil

在线全文

学校读者我要写书评

暂无评论

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

Assessment of cO_(2)storage prospect based on physical properties of rio Bonito Formation rock units

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy Geoscience 2024年第1期5卷 321-330页

作者： richardson M.Abraham-A Stephanie San Martín cañas Isabella F.S.Miranda colombo c.G.Tassinari Institute of Energy and Environment(IEE) University of São Paulo(USP)Brazil research centre for Greenhouse Gas Innovation(rcGI) University of Sãao Paulo(USP)Brazil

The physical properties of the rock units associated with the rio Bonito Formation are presented in this study with the focus on modelling reservoir quality based on petrophysics-derived parameters to evaluate cO_(2)storage *** involves the modelling of the reservoir depths,thicknesses,flow zone indicators(FZI),and effective permeability(Keff)and presenting the cO_(2)storage efficiency factors peculiar to the rock units of the study *** results presented by this study for the stated objectives are not quite common in the *** values range from 200 mD to higher than 2000 mD,and FZI values are generally above 1.0 mm and up to 13.0 mm within the portions covered by the drilled *** sandstone units recorded are up to 20 m thick in some *** Keff and FZI models indicate the sandstone reservoirs as permeable units to support the injection and circulation of cO_(2)within the potential reservoir units of the rio Bonio Formation across São Paulo *** from some points in the southeastern part of the study location,where the rio Bonito are delineated at depths less than 800 m(minimum cO_(2)storage depth based on best practices),other portions are deeper,ranging from 950 m to 3500 ***-bedded layers will affect the integrity of the rocks as cO_(2)storage tanks or reservoir seals/traps/overburden within the *** bed thicknesses are up to 20 m in some ***,hybrid cO_(2)reservoir units are feasible,especially in portions where thin siltstone layers are sandwiched between sandstone units to provide considerable thicknesses based on cO_(2)storage *** current study shows that useable areas considering reservoir thickness,depth,and other physical qualities will significantly control the cO_(2)storage efficiency of the study *** studies featuring a detailed geophysical exploration of the site to confirm the availability and saturations of preexisting fluid(hydrocarbon and water)are encouraged

关键词： rio Bonito Effective permeability Fluid transmissibility cO_(2)storage prospect reservoir quality Overburden integrity Flow zones

Mantle avalanches in a Venus-like stagnant lid planet

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2024年第5期8卷 686-702页

作者： Madeleine c.Kerr Dave r.Stegman Institute of Geophysics and Planetary Physics Scripps Institution of Oceanography University of California

Stagnant lid planets are characterized by a globe-encircling, conducting lid that is thick and strong, which leads to reduced global surface heat flows. consequently, the mantles of such planets can have warmer interiors than Earth, and interestingly, a pyrolitic mantle composition under warmer conditions is predicted to have a distinctly different mantle transition zone compared to the present-day Earth(Hirose, 2002; Stixrude and Lithgow-Bertelloni, 2011; Ichikawa et al., 2014; Dannberg et al, 2022). Instead of olivine primarily transforming into its higher-pressure polymorphs such as wadsleyite and then ringwoodite, at pressures corresponding to410 km and 520 km depth in Earth, respectively, it instead transforms into a mineral assemblage of wadsleyite, majorite, and ferropericlase(WMF), and then to majorite + ferropericlase(MF), before finally transforming into bridgmanite at pressures corresponding to 660 km depth in Earth(Stixrude and Lithgow-Bertelloni, 2011; Ichikawa et al., 2014). convective motions in stagnant lid planets are dominated by small-scale instabilities(cold drips) forming within the mobile rheological sublayer under the rigid lid. Using ASPEcT and a thermodynamic model of a pyrolitic mantle composition generated by HeFESTo, we show that under certain conditions, the small drips can pond atop the WMF-MF mineral phase transition. The barrier to convective flow arises from the WMF mineral phase assemblage having an effective negative thermal expansivity(Stixrude and Lithgow-Bertelloni, 2022). Although large-scale downwellings that typically occur within mobile lid planets are able to pass through the WMF zone without difficulty(Dannberg et al., 2022; Li rP et al.,2024), the smaller and less negatively buoyant nature of downwelling drips in stagnant lid planets are more susceptible to these effects,which leads to an ephemeral layering of the mantle. Our numerical models show that in stagnant lid planets with mantle potential temperatures that exceed

关键词： Venus mantle avalanches numerical modelling phase transitions

How to fill the biodiversity data gap:Is it better to invest in fieldwork or curation?

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Plant Diversity 2024年第1期46卷 39-48页

作者： carlos A.Vargas Marius Bottin Tiina Sarkinen James E.richardson Marcela celis Boris Villanueva Adriana Sanchez Programa de Biología Facultad de Ciencias NaturalesUniversidad del RosarioBogotaD.C.Colombia Subdireccion científica Jardín Botanico de Bogota“Jose Celestino Mutis”BogotaD.C.Colombia Independent researcher BogotaD.C.Colombia Tropical Diversity Section Royal Botanic Garden EdinburghUK School of Biological Earth and Environmental SciencesUniversity College CorkCorkIreland Departamento de Química y Biología Universidad del NorteKm.5 Vía Puerto ColombiaArea Metropolitana de Barranquilla 081007Colombia

Data gaps and biases are two important issues that affect the quality of biodiversity information and downstream *** how best to fill existing gaps and account for biases is necessary to improve our current information most *** current main approaches for obtaining and improving data include(1)curation of biological collections,and(2)***,the comparative effectiveness of these approaches in improving biodiversity data remains little *** used the Flora de Bogota project to study the magnitude of change in species richness,spatial coverage,and sample coverage of plant records based on curation versus *** process of curation resulted in a decrease in species richness(synonym and error removal),but it significantly increased the number of records per *** contributed to a slight increase in species richness,via accumulation of new ***,curation led to increases in spatial coverage,species observed by locality,the number of plant records by species,and localities by species compared to ***,curationwas more efficient in producing new information compared to fieldwork,mainly because of the large number of records available in *** recommend intensive curatorial work as the first step in increasing biodiversity data quality and quantity,to identify bias and gaps at the regional scale that can then be targeted with *** stepwise strategy would enable fieldwork to be planned more costeffectively given the limited resources for biodiversity exploration and characterization.

关键词： colombia Flora de Bogota Sample coverage Species richness Tropical Andes

维普期刊数据库

Effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

在线全文

学校读者我要写书评

暂无评论

International Journal of coal Science & Technology 2024年第3期11卷 86-101页

作者： F.Animah c.Keles W.r.reed E.Sarver Department of Mining and Minerals Engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(cAcs)to reduce respirable dust in key operator *** detailed dust characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter cAc on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affected by either scrubber or the ***,the wet scrubber and cAc appeared to decrease the overall particle size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： respirable dust Dust control SEM–EDX Scrubber canopy air curtain Silica

Investigations of nuclear chirality at iThemba LABS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第2期19卷 7-38页

作者： r.A.Bark E.A.Lawrie c.Liu S.Y.Wang iThemba Laboratory for Accelerator Based Sciences National Research FoundationP.O.Box 722Somerset-West 7129South Africa Department of Physics University of the Western CapePrivate Bag X177535BellvilleSouth Africa Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China

Progress in the studies of chirality in atomic nuclei at iThemba LABS is *** regions of chirality,around mass 80 and 190 have been discovered using the AFrODITE array,specifically in the nuclei^(74)As,^(78,80,82)Br,^(81)Kr,and^(193,194,198)*** phenomena have been observed,including multiple chiral bands in the same nucleus,the coexistence of octupole correlations and nuclear chirality,and the coexistence of pseudo spin and nuclear *** best example of chiral degeneracy to date was found in ^(194)*** level scheme of ^(106)Ag has been revisited and interpreted in terms of two-and four-quasiparticle *** using the particle-rotor model have shown that the fingerprints of chirality in the two-quasiparticle system only can occur in an idealised model *** systems with a higher number of quasiparticles,the calculations showed that nuclear chirality can persist.

关键词： chirality high-spin states particle-rotor model

convergent plate boundary environments for formation of≥3800 Ma mafic-ultramafic assemblages(Isua area,Greenland):Implications for early global geodynamics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geoscience Frontiers 2024年第3期15卷 119-136页

作者： Allen P.Nutman clark r.L.Friend Vickie c.Bennett School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss terrane on the south side of the Eoarchean Isua supracrustal belt,ultramafic rocks with relict abyssal peridotite mineralogy(Bennett et al.,2002;Friend et al.,2002;Nutman et al.,2007;rollinson,2007;van de Löcht et al.,2020),layered gabbros with cumulate ultramafic rocks,basalts and associated siliceous sedimentary rocks were tectonically-imbricated,prior to and during intrusion of ca.3800 Ma *** with3800 Ma basalts in the Outer Arc Group of the nearby Isua supracrustal belt,the composition of all these mafic rocks(e.g.,Th-Hf-Nb systematics,high Th/Yb,Ba/Nb,Ba/Yb ratios and negative Nb and Ti anomalies)shows affinity with modern suprasubduction rocks whose genesis involved fluid fluxing of the upper ***,the majority of these samples have Ba/Nb and Ba/Yb values less than in modern island arc magmas,but similar to many backarc basin magmas(e.g.,Pearce and Stern,2006).It is unknown whether these ca.3800 Ma mafic rocks are,(i)arc rocks where the Ba/Nb and Ba/Yb signatures reflect lower surficial Ba in Eoarchean oceanic settings,or(ii)in direct comparison with Phanerozoic suites,these signatures reflect a back-arc setting with interplay between fluid fluxing and decompressional *** tectonic intercalation of upper mantle with lower and upper crustal rocks,combined with the fluid-fluxing influences seen in chemistry of all the mafic rocks is best accommodated in a compressional Eoarchean convergent plate boundary setting within a mobile-lid *** stagnant lid scenarios of crust formation,if operative,must have co-existed or alternated with mobile-lid regimes by 3800 Ma.

关键词： Eoarchean Fluid-fluxing Plate tectonics Suprasubduction crustal evolution

cannabinoids and endocannabinoids as therapeutics for nervous system disorders:preclinical models and clinical studies

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural regeneration research 2024年第4期19卷 788-799页

作者： r.Scott Duncan Sean M.riordan Matthew c.Gernon Peter Koulen Department of Ophthalmology School of MedicineUniversity of Missouri Department of Biomedical Sciences School of MedicineUniversity of Missouri

cannabinoids are lipophilic substances derived from cannabis sativa that can exert a variety of effects in the human *** have been studied in cellular and animal models as well as in human clinical trials for their therapeutic benefits in several human *** of these include central nervous system(cNS)diseases and dysfunctions such as forms of epilepsy,multiple sclerosis,Parkinson’s disease,pain and neuropsychiatric *** addition,the endogenously produced cannabinoid lipids,endocannabinoids,are critical for normal cNS function,and if controlled or modified,may represent an additional therapeutic avenue for cNS *** review discusses in vitro cellular,ex vivo tissue and in vivo animal model studies on cannabinoids and their utility as therapeutics in multiple cNS *** addition,the review provides an overview on the use of cannabinoids in human clinical trials for a variety of cNS *** and endocannabinoids hold promise for use as disease modifiers and therapeutic agents for the prevention or treatment of neurodegenerative diseases and neurological disorders.

关键词： anandamide cannabidiol cannabinoid endocannabinoid epilepsy multiple sclerosis neurodegeneration neuroprotection tetrahydrocannabinol

维普期刊数据库