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Neurodevelopmental defects as a primer of neurodegeneration:lessons from spinal muscular atrophy and Huntington's disease

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Neural Regeneration Research 2023年第9期18卷 1952-1953页

作者： stuart j.Grice j.-Long Liu Medical Research Council Functional Genomics Unit Department of PhysiologyAnatomy and GeneticsUniversity of OxfordOxfordUK School of Life Science and Technology ShanghaiTech UniversityShanghaiChina

Developmental motifs in neurodegeneration:Neurodegeneration,the prominent feature of neurodegenerative disease,is characterized by the progressive and selective loss of neuronal *** some of the pathologies caused by neurodegeneration may be irreversible,early intervention will be required for the treatments that aim to slow or halt the manifestation of these ***,neurodegeneration evokes the idea of a progressive decline of brain function.

关键词： neurodegeneration Huntington function

The effects of gonadal hormones on learning and memory in male mammals： A review

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Current Zoology 2011年第4期57卷 543-558页

作者： stuart T. LEONARD Peter j. WINSAUER Department of Pharmacology and Experimental Therapeutics Louisiana State University Health Sciences Center 1901 Perdido Street New Orleans LA 70112-1393

The primary role of the gonadal steroid hormones in mammals is to regulate reproduction and related behaviors; however, both androgens and estrogens are also integrally involved in mediating higher brain function and processes including cognition, neural development, and neural plasticity. In particular, a number of studies show that estradiol modulates dendritic spine growth and synapse density (synaptic plasticity) in the hippocampus of females, and that increased estradiol levels are generally associated with improvements on a variety of learning and memory tasks. While the maj.rity of research has focused on the beneficial effects of estradiol in females, much less attention has been given to testosterone and its effects on learning and memory in males. Similar to estradiol titers in females, testosterone titers in males decline with age, albeit more gradually, and this decline has been correlated with impairment of certain cognitive tasks. Moreover, studies involving both humans and animals indicate that testosterone and its metabolites can augment responding on certain behavioral tasks, depending on the subj.ct’s current hormonal state, the response required, and the stimuli involved (e.g., those involving spatial or nonspatial stimuli). While the exact mechanisms by which testosterone exerts its effects on learning and memory are not fully understood, recent findings suggest that testosterone modulates learning and memory in males through an interaction with the cholinergic system. The overall obj.ctive of this review is to discuss studies investigating the role of the gonadal hormones in mediating learning and memory processes in male mammals.

关键词：记忆能力哺乳动物性腺激素学习雄性突触可塑性神经系统发育睾丸激素

Vocal repertoire of the New Zealand kea parrot Nestor notabilis

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Current Zoology 2012年第5期58卷 727-740页

作者： Raoul SCHWING stuart PARSONS Ximena j. NELSON School of Biological Sciences University of Auckland Private Bag 92019 Auckland New Zealand School of Biological Sciences University of Canterbury Private Bag 4800 Christchurch New Zealand

The unique alpine-living kea parrotNestor notabilishas been the focus of numerous cognitive studies, but its communication system has so far been largely neglected. We examined 2,884 calls recorded in New Zealand’s Southern Alps. Based on audio and visual spectrographic differences, these calls were categorised into seven distinct call types: the non-oscillating ‘screech’ contact call and ‘mew’; and the oscillating ‘trill’, ‘chatter’, ‘warble’ and ‘whistle’; and a hybrid ‘screech-trill’. Most of these calls contained aspects that were individually unique, in addition to potentially encoding for an individual’s sex and age. Additionally, for each recording, the sender’s previous and next calls were noted, as well as any response given by conspecifics. We found that the previous and next calls made by the sender were most often of the same type, and that the next most likely preceding and/or following call type was the screech call, a contact call which sounds like the ‘kee-ah’ from which the bird’s name derives. As a social bird capable of covering large distances over visually obstructive terrain, long distance contact calls may be of considerable importance for social cohesion. Contact calls allow kea to locate conspecifics and congregate in temporary groups for social activities. The most likely response to any given call was a screech, usually followed by the same type of call as the initial call made by the sender, although responses differed depending on the age of the caller. The exception was the warble, the kea’s play call, to which the most likely response was another warble. Being the most common call type, as well as the default response to another call, it appears that the ‘contagious’ screech contact call plays a central role in kea vocal communication and social cohesion.

关键词：新西兰鹦鹉初始呼叫曲目联系方式阿尔卑斯山尖叫声认知研究

Sizing up feature descriptors for macromolecular machine learning with polymeric biomaterials

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npj.Computational Materials 2023年第1期9卷 1287-1296页

作者： Samantha stuart j.ffrey Watchorn Frank X.Gu Institute of Biomedical Engineering University of TorontoTorontoOntarioCanada Department of Chemical Engineering and Applied Chemistry University of TorontoTorontoOntarioCanada

It has proved challenging to represent the behavior of polymeric macromolecules as machine learning features for biomaterial interaction *** are several approaches to this representation,yet no consensus for a universal representational framework,in part due to the sensitivity of biomacromolecular interactions to polymer *** help navigate the process of feature engineering,we provide an overview of popular classes of data representations for polymeric biomaterial machine learning while discussing their merits and ***,increasing the accessibility of polymeric biomaterial feature engineering knowledge will contribute to the goal of accelerating clinical translation from biomaterials discovery.

关键词： properties prediction biomaterials

A SteMNess perspective of survival motor neuron function： splicing factors in stem cell biology and disease

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Frontiers in Biology 2015年第4期10卷 297-309页

作者： stuart j. Grice j.-Long Liu MRC Functional Genomics Unit Department of Physiology Anatomy and Genetics University of Oxford South Parks RoadOxford OX1 3PT UK

Genome-wide analyses of metazoan messenger RNA （mRNA） species are unveiling the extensive transcriptional diversity generated by alternative splicing （AS）. Research is also beginning to identify the splicing factors and AS events required to maintain the balance between stem cell renewal （i.e stemness properties） and differentiation. One set of proteins at the center of spliceosome biogenesis are the survival motor neuron （SMN） complex constituents, which have a critical role in the assembly of spliceosomal small nuclear ribonucleoproteins （snRNPs） in all cells. In this review we discuss what is currently known about how AS controls pluripotency and cell fate and consider how an increased requirement for splicing factors, including SMN, helps to maintain an enrichment of stem cell-specific AS events. Furthermore, we highlight studies showing that mutations in specific splicing factors can lead to the aberrant development, and cause targeted degeneration of the nervous system. Using SMN as an example, we discuss the perspective of how stem cell-specific changes in splicing factors can lead to developmental defects and the selective degeneration of particular tissues. Finally we consider the expanding role of SMN, and other splicing factors, in the regulation of gene expression in stem cell biology, thereby providing insight into a number of debilitating diseases.

关键词： stem cells splicing survival motor neuron (SMN) spinal muscular atrophy (SMA)

Land use and dingo baiting are correlated with the density of kangaroos in rangeland systems

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Integrative Zoology 2023年第2期18卷 299-315页

作者： stuart j.DAWSON Tracey L.KREPLINS Malcolm S.KENNEDY j.anita RENWICK Mark A.COWAN Patricia A.FLEMING Terrestrial Ecosystem Science and Sustainability Harry Butler InstituteMurdoch UniversityMurdochAustralia Department of Primary Industries and Regional Development(present address) South PerthAustralia Department of Primary Industries and Regional Development NorthamAustralia Queensland Department of Environment and Science Australia Queensland Department of Environment and Science MoggillAustralia Department of Biodiversity Conservation and AttractionsWoodvaleAustralia

Rangelands worldwide have been subj.ct to broadscale modiﬁcation,such as widespread predator control,intro-duction of permanent livestock water and altered vegetation to improve *** Australia,these landscape changes have resulted in kangaroos(*** macropods)populations increasing over the past 200 ***-garoos are a key contributor to total grazing pressure and in conj.nction with livestock and feral herbivores have been linked to land *** used 22 years of aerial survey data to investigate whether the density of 3 macropod species in the southern rangelands of Western Australia was associated with:(i)land use,including type of livestock,total livestock,density of feral goats,type of land tenure,and kangaroo commercial harvest effort;(ii)predator management,including permitted dingo control effort,estimated dingo abundance,and presence of the State Barrier Fence(a dingo exclusion fence);and(iii)environmental variables:ruggedness,rainfall,fractional cover,and total standing dry *** kangaroos(Osphranter rufus)were most abundant inﬂat,open vegetation,on pastoral land,where area permitted for dingo control was high,and numbers were positively associated with antecedent rainfall with a 12-month *** grey kangaroos(Macropus fuliginosus)were most abundant onﬂat,agricultural land,but less abundant in areas with high permitted dingo ***(Osphranter robustus)were most abundant in rugged pastoral land with open vegetation,where permitted dingo control was *** environmental variables are key drivers of landscape productivity and kangaroo populations,anthropogenic factors such as land use and permitted dingo control are strongly associated with kangaroo abundance.

关键词： herbivores livestock macropods overgrazing rangelands total grazing pressure

The microstructure characteristics and fracture behavior of the polyhedral primary iron-rich phase and plate-shaped eutectic iron-rich phase in a high-pressure die-cast AlSi10MnMg alloy

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j.urnal of Materials Science & Technology 2023年第9期140卷 201-209页

作者： X.Y.j.ao Y.X.Liu j.Wang W.N.Liu A.X.Wan stuart Wiesner S.M.Xiong School of Materials Science and Engineering Northeastern UniversityShenyang 110819China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Lightweight Structural Materials Liaoning ProvinceNortheastern UniversityShenyang 110819China Key Laboratory for Advanced Materials Processing Technology Tsinghua UniversityBeijing 100084China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Ein Unternehmen der ALUMINIUM RHEINFELDEN Group RHEINFELDEN 79618Germany

The characterization of multiple iron-rich phases in high-pressure die-cast AlSi10MnMg alloy was *** was focused on the formation and fracture behavior of the primary iron-rich phase((P-IMC)_(I))formed in the shot sleeve and plate-shaped eutectic iron-rich phase in high-pressure die cast(HPDC)AlSi10MnMg *** show that multiple types of iron-rich phases with various morphologies,in-cluding primary iron-rich phases(polyhedral(P-IMC)_(I) and(P-IMC)_(II))and eutectic iron-rich phases(plate-shaped,net shape,and fish-bone shape),were found in HPDC ***(P-IMC)_(I) formed in the shot sleeve were distributed in the interface between primaryα-Al and binary Al-Si *** size(P-IMC)_(II) and various eutectic iron-rich phases formed in the die cavity and they were distributed in Al-Si binary *** primary iron-rich phases belonged to a simple cubic crystal structure with a lattice constant a=1.265 nm and they exhibited a lateral growth characteristic with a termination of{110}surface.βphase was surrounded byδphase and they coexisted in a plate-shaped iron-rich ***-density stacking fault inβphase andδ/βinterface provided an excellent nucleation site forδ*** mechanical behavior,the stress concentration caused by eutectic iron-rich phases was far less than(P-IMC)_(I) and it would not cause crack initiation along the eutectic cluster *** addition,(P-IMC)_(I) showed the worst deformation coordination with primaryα-Al while the plate-shaped eutectic iron-rich phase exhibited similar deformation characteristics with silicon particles.

关键词： AlSi10MnMg High-pressure die casting Multiple iron-rich phases

High-performance polymer electrolyte membranes incorporated with 2D silica nanosheets in high-temperature proton exchange membrane fuel cells

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j.urnal of Energy Chemistry 2022年第1期31卷 323-334,I0009页

作者： Zunmin Guo j.anuo Chen j.e j.ng Byun Rongsheng Cai Maria Perez-Page Madhumita Sahoo Zhaoqi j. Sarah j.Haigh stuart M.Holmes Department of Chemical Engineering and Analytical Science The University of ManchesterM139PLUnited Kingdom Department of Materials The University of ManchesterM139PLUnited Kingdom

Silica nanosheets(SN)derived from natural vermiculite(Verm)were successfully incorporated into polyethersulfone-polyvinylpyrrolidone(PES-PVP)polymer to fabricate high-temperature proton exchange membranes(HT-PEMs).The content of SN filler was varied(0.1-0.75 wt%)to study its influence on proton conductivity,power density and *** from the hydroxyl groups of SN that enable the formation of additional proton-transferring pathways,the inorganic-organic membrane displayed enhanced proton conductivity of 48.2 mS/cm and power density of 495 mW/cm^(2) at 150℃ without humidification when the content of SN is 0.25 wt%.Furthermore,exfoliated SN(E-SN)and sulfonated SN(S-SN),which were fabricated by a liquid-phase exfoliation method and silane condensation,respectively,were embedded in PES-PVP polymer matrix by a simple blending *** to the significant contribution from sulfonic groups in S-SN,the membrane with 0.25 wt%S-SN reached the highest proton conductivity of51.5 mS/cm and peak power density of 546 mW/cm^(2) at150℃,48%higher than the pristine PES-PVP *** to unaltered PES-PVP membrane,SN added hybrid composite membrane demonstrated excellent durability for the fuel cell at 150℃.Using a facile method to prepare 2D SN from natural clay minerals,the strategy of exfoliation and functionalization of SN can be potentially used in the production of HT-PEMs.

关键词： Silica nanosheets Vermiculite High-temperature proton exchange membrane Proton conductivity

Relationships between regulated DBPs and emerging DBPs of health concern in U.S. drinking water

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j.urnal of Environmental Sciences 2022年第7期34卷 161-172页

作者： stuart W.Krasner Ai j.a Chih-Fen T.Lee Raha Shirkhani j.shua M.Allen Susan D.Richardson Michael j.Plewa Metropolitan Water District of Southern California Water Quality LaboratoryCA 91750USA Department of Chemistry and Biochemistry University of South CarolinaSC 29208USA Department of Crop Sciences University of Illinois at Urbana-ChampaignIL 61801USA Safe Global Water Institute University of Illinois at Urbana-ChampaignIL 61801USA

A survey was conducted at eight U.S. drinking water plants, that spanned a wide range of water qualities and treatment/disinfection practices. Plants that treated heavily-wastewaterimpacted source waters had lower trihalomethane to dihaloacetonitrile ratios due to the presence of more organic nitrogen and HAN precursors. As the bromide to total organic carbon ratio increased, there was more bromine incorporation into DBPs. This has been shown in other studies for THMs and selected emerging DBPs(HANs), whereas this study examined bromine incorporation for a wider group of emerging DBPs(haloacetaldehydes, halonitromethanes). Moreover, bromine incorporation into the emerging DBPs was, in general, similar to that of the THMs. Epidemiology studies that show an association between adverse health effects and brominated THMs may be due to the formation of brominated emerging DBPs of heath concern. Plants with higher free chlorine contact times before ammonia addition to form chloramines had less iodinated DBP formation in chloraminated distribution systems, where there was more oxidation of the iodide to iodate(a sink for the iodide) by the chlorine. This has been shown in many bench-scale studies(primarily for iodinated THMs), but seldom in full-scale studies(where this study also showed the impact on total organic iodine. Collectively, the THMs, haloacetic acids, and emerging DBPs accounted for a significant portion of the TOCl, TOBr, and TOI;however, ~50% of the TOCl and TOBr is still unknown. The correlation of the sum of detected DBPs with the TOCl and TOBr suggests that they can be used as reliable surrogates.

关键词： Disinfection by-products Total organic bromine Total organic iodine Trihalomethanes Haloacetonitriles Haloacetaldehydes Iodo-trihalomethanes Iodoacetic acids