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

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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

Towards a sustainable geoliner construction in landflls by potential blending of fly ash with kaolin clay alternative:a review with an insight to Indian scenario

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Waste Disposal and Sustainable Energy 2024年第2期6卷 243-258页

作者： Kshitij Kumar Biswajit paul Department of Environmental Science and Engineering Indian Institute of Technology(Indian School of Mines)Dhanbad 826004JharkhandIndia

Electricity generated through coal-based Thermal Power Plants(TPPs)has played a pivotal role in shaping modern civiliza-tion,revolutionizing industries,and improving the quality of life for billions of people *** TPPs contribute to about 37%-40%of the global energy *** production,in turn,has a direct impact on the economy of any *** from this boon to humankind,these TPPs combusting coal as their primary fuel also have specific environmen-tal impacts,the major ones being water,air,and soil pollution due to unscientific disposal of high-quantity fly ash produced *** we can put this ash to good use,it may assist us in mitigating the pollution caused by *** there are many conventional uses of fly ash,such as a pozzolanic material in the cement industry,more pathways need to be discovered to balance the high generation quantities with ***,a detailed description of its use in potential geoliner applications is presented in this article.A geoliner or a landfill liner acts as a virtually impenetrable layer to mitigate the leachate penetration into the underneath subsoil and groundwater,thus preventing *** are presently some studies that support the use of only fly ash in such ***,the properties of the geoliners using it are not so good to significantly mitigate environmental degradation owing to its high permeability and low densification *** bentonite conventionally used has limited deposits and is mined intensively for its use as a natural *** depos-its must also be conserved,and an alternative material that may serve similar application benefits,like bentonite,must be *** desired aim can be fulfilled if we blend this combustion residue with other suitable materials(such as kaolinite clay)with low ***,the article focuses on the possibilities of blending fly ash with different clays for geoliner construction to improve the in

关键词： Fly ash-Geoliner Environmental management Composite liner systems Bentonite Kaolin clay

Strain-dependent alpha-synuclein spreading in Parkinson's disease and multiple system atrophy

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Neural Regeneration Research 2024年第12期19卷 2581-2582页

作者： Shuyu Zhang paul Lingor Department of Neurology School of MedicineUniversity Hospital rechts der IsarTechnical University of MunichMunichGermany Department of Neurology University Medical Center GöttingenGöttingenGermany Center for Biostructural Imaging of Neurodegeneration University Medical Center GöttingenGöttingenGermany

Parkinson's disease(PD) and atypical Parkinsonian syndromes,such as multiple system atrophy(MSA) and Dementia with Lewy bodies,are neurodegenerative movement disorders characterized by the accumulation of alphasynuclein(a-syn) *** a-syn aggregates propagate throughout the brain in a prion-like manner,where pathological a-syn recruits endogenous a-syn to form insoluble *** forms representing intermediates on the way to insoluble aggregates result in the most pronounced neurotoxic effects.

关键词： atrophy endogenous atypical

Tensor perturbations from bounce inflation scenario in f(Q)gravity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun Hu Tanmoy paul Taotao Qiu Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of Technology Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations *** is well-known,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational waves(PGWs)that are to be detected by the next generation of GW *** discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation *** general form of the tensor power spectrum is obtained both for large as well as small scale *** a result,we show both kinds of modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational waves’amplitude in the background of the f(Q)bounce-inflation ***,we study the LQC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.

关键词： bounce cosmology modified gravity cosmological perturbations

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

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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

Smoking of Carica papaya in Nigeria:The rationale,the public health effects and policies for intervention

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Asian Pacific Journal of Tropical Medicine 2024年第3期17卷 95-96页

作者： Abolaji paul Adekeye Mental Health Department Federal Teaching HospitalIdo-EkitiEkiti StateNigeria Mental Health Department Afe Babalola UniversityAdo-EkitiEkiti StateNigeria

Psychoactive substance use is characterized by the habitual use of substances that have significant effects in altering the activities of neurotransmitters in certain regions of the ***,these alterations manifest as c... 详细信息

关键词： rational behaviour emotional

Surface engineering with ionic polymers on membranes for boron removal

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 61-69页

作者： Xiting Zhang Chenyi Fang J paul Chen Sui Zhang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117576Singapore Department of Civil and Environmental Engineering National University of SingaporeSingapore 119260Singapore College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seawater and wastewater using reverse osmosis membrane technologies is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rejection,which is usually accompanied by substantial sacrifice in water *** study delves into the surface engineering of low-pressure reverse osmosis membranes,aiming to elevate boron removal efficiency while maintaining optimal salt rejection and water *** were modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a water permeability of 9.2±0.1 L·m^(-2)·h^(-1)·bar^(-1),NaCl rejection of 95.8%±0.3%,and boron rejection of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** water permeability is reduced by less than 15%,while the boron rejection is 3.7 times higher compared to the blank *** research provides a promising avenue for enhancing boron removal in reverse osmosis membranes and addressing water quality concerns in the desalination process.

关键词： membrane low-pressure reverse osmosis boron surface engineering

The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： paul B.Wignall David P.G.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

Improving Heat Transfer in Parabolic Trough Solar Collectors by Magnetic Nanofluids

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Energy Engineering 2024年第4期121卷 835-848页

作者： Ritesh Singh Abhishek Gupta Akshoy Ranjan paul Bireswar paul Suvash C.Saha Department of Applied Mechanics Motilal Nehru National Institute of Technology AllahabadPrayagrajIndia Department of Mechanical and Mechatronic Engineering University of Technology SydneySydneyAustralia

A parabolic trough solar collector(PTSC)converts solar radiation into thermal ***,low thermal efficiency of PTSC poses a hindrance to the deployment of solar thermal power *** performance of PTSC is enhanced in this study by incorporating magnetic nanoparticles into the working *** circular receiver pipe,with dimensions of 66 mm diameter,2 mm thickness,and 24 m length,is exposed to uniform temperature and velocity *** working fluid,Therminol-66,is supplemented with Fe3O4 magnetic nanoparticles at concentrations ranging from 1%to 4%.The findings demonstrate that the inclusion of nanoparticles increases the convective heat transfer coefficient(HTC)of the PTSC,with higher nanoparticle volume fractions leading to greater heat transfer but increased pressure *** thermal enhancement factor(TEF)of the PTSC is positively affected by the volume fraction of nanoparticles,both with and without a magnetic ***,the scenario with a 4%nanoparticle volume fraction and a magnetic field strength of 250 G exhibits the highest TEF,indicating superior thermal *** findings offer potential avenues for improving the efficiency of PTSCs in solar thermal plants by introducing magnetic nanoparticles into the working fluid.

关键词： Parabolic trough solar collector(PTSC) magnetic nanofluid(MNF) heat transfer convective heat transfer coefficient(HTC) thermal enhancement factor(TEF)