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A radical reinterpretation of the growth and form of the stromatolite Conophyton lituus(Maslov)from evidence of syngenetic biofilm mineralisation

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Journal of Palaeogeography 2022年第1期11卷 69-84页

作者： robert v.burne Research School of Earth Sciences The Australian National University CanberraACT 0200Australia School of Earth and Environmental Sciences The University of QueenslandBrisbaneQLD 4072Australia

Conophyton(Maslov)is a cylindroidal stromatolite form-genus characterized by nested conical ***-preserved Conophyton,up to 4 m tall and with basal diameters of up to 50 cm,are exposed in the Proterozoic Atar Formation of Mauritania,where many occur together,in growth position,as fields of individual columns spaced between 5 and 70 cm *** uniformity of these forms and their regular distribution suggest that they grew in quiet-water environments below wave *** for their penecontemporaneous organomineralization is indicated by nearby toppled examples of undeformed Conophyton forms alongside eroded lithified Conophyton fragments in carbonate *** characteristics of Conophyton have been used to classify the structures-the form of the lamination and the nature of its axial structure.A mathematical/physical model provides an explanation for the growth pattern of *** predicts that coniform structures with thickened axial zones form when upward organic growth of a biofilm moderately exceeds the rate of its *** varying characteristics of these features between different forms of Conophyton are thought to reflect biomineralization of the decaying biofilm rather than differences in the composition of microbial communities.A modern example of a syngenetic mineralization process capable of producing similar structures has been observed in the contemporary sediments of Lake Preston,Western Australia,where benthic microbial mats are being transformed into coniform lithified *** initial biomineralization of the coniform mat forms magnesium silicate that first coats and permineralizes web-like microbial extracellular polymeric substances(EPS)and then coalesces into a uniform mass that provides mechanical strength to the *** a later stage,massive carbonate crystal growth occurs that over-prints much of this texture,leaving only small,remnant areas of the magnesium silicate *** fossil Conophyton are composed o

关键词： Conophyton Morphogenesis Proterozoic Stromatolite Microbialite Mineralisation Biofilm Lake Clifton Lake Preston Maslov

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A general mirror equivalence theorem for coset vertex operator algebras

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Science China Mathematics 2024年

作者： robert McRae Yau Mathematical Sciences Center Tsinghua University

We prove a general mirror duality theorem for a subalgebra U of a simple conformal vertex algebra A and its commutant v=ComA（U）.Specifically,we assume that A≌⊕i∈IUi×Uias a U×v-module,where the U-modules Uiare simple and distinct and are objects of a semisimple braided ribbon category of U-modules,and the v-modules viare semisimple and contained in a （not necessarily rigid） braided tensor category of *** also assume U=ComA（v）.Under these conditions,we construct a braid-reversed tensor equivalenceτ:UA→vA,where UAis the semisimple category of U-modules with simple objects Ui,i∈I,and vAis the category of v-modules whose objects are finite direct sums of *** particular,the v-modules viare simple and distinct,and vAis a rigid tensor *** an application,we find a rigid semisimple tensor subcategory of modules for the virasoro algebra at central charge 13+6p+6p-1,p∈Z 2,which is braided tensor equivalent to an abelian 3-cocycle twist of the category of finite-dimensional ***,the virasoro vertex operator algebra at central charge 13+6p+6p-1is the PSL2（C）-fixed-point subalgebra of a simple conformal vertex algebra W（-p）,analogous to the realization of the virasoro vertex operator algebra at central charge 13-6p-6p-1as the PSL2（C）-fixed-point subalgebra of the triplet algebra W（p）.

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Commentary on “Why people should run after positive affective experiences instead of health benefits”

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Journal of Sport and Health Science 2024年第4期13卷 451-452页

作者： Ting Wang Jinghua Chen robert Schinke Liye Zou Body-Brain-Mind Laboratory School of PsychologyShenzhen UniversityShenzhen 518060China School of Kinesiology and Health Sciences Laurentian UniversitySudburyON P3E 2C6Canada

Maltagliati et al.1 recently highlighted the vital role of affective experiences in promoting physical activity(PA).The authors suggested that positive affective experiences,rather than health benefits,can tip the balance in favor of PA over sedentary *** authors proposed a new formal decision model between PA and sedentary alternatives and reported that when health benefits are the unique reason to action,the costs of PA(e.g.,effort)and the subjective value(Sv)of sedentary alternatives(v_(sed))are the main drivers of decision-making processes.

关键词： benefits formal decision

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Effects of soil metal(loid)s pollution on microbial activities and environmental risks in an abandoned chemical smelting site

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Journal of Environmental Sciences 2024年第9期143卷 60-70页

作者： Hao Li Jun Yao Jianli Liu Ning Min Geoffrey Sunahara Dongyang Men robert Duran School of Water Resources and Environment Research Center of Environmental Science and EngineeringChina University of Geosciences(Beijing)Beijing 100083China Department of Natural Resource Sciences McGill University21111Lakeshore DriveSte-Anne-de-BellevueQuebecH9X 3V9Canada Equipe Environnement et Microbiologie MELODY groupUniversitéde Pau et des Pays de l’AdourE2S-UPPAIPREM UMR CNRS 5254BP 115564013 Pau CedexFrance

Abandoned chemical smelting sites containing toxic substances can seriously threaten and pose a risk to the surrounding ecological *** samples were collected from different depths(0 to 13 m)and analyzed for metal(loid)s content and fractionation,as well as microbial *** potential ecological risk indices for the different soil depths(ordered from high to low)were:1 m(D-1)>surface(S-0)>5 m(D-5)>13 m(D-13)>9 m(D-9),ranging between 1840.65-13,089.62,and representing extremely high environmental risks,of which Cd(and probably not arsenic)contributed to the highest environmental risk.A modified combined pollution risk index(MCR)combining total content and mobile proportion of metal(loid)s,and relative toxicities,was used to evaluate the degree of contamination and potential environmental *** the near-surface samples(S-0 and D-1 layers),the MCR considered that As,Cd,Pb,Sb,and Zn achieved high and alarming degrees of contamination,whereas Fe,Mn,and Ti were negligible or low to moderate pollution *** microcalorimetry and enzymatic activity measurements of contaminated soil samples were used to assess the microbial metabolic activity *** analysis elucidated the relationship between metal(loid)s exchangeable fraction or content and microbial activity characteristics(pvity in the D-1 layer was low presumably due to heavy metal *** activity indicators and microcalorimetric growth rate(k)measurements were considered sensitive indicators to reflect the soil microbial activities in abandoned chemical smelting sites.

关键词： Abandoned chemical smelting sites Microbial activities Modified combined pollution risk Microcalorimetry Enzymatic activities

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Long-Term Impact of Acute Retinoic Acid Supplementation at the Young Age on Testicular Architecture of Wistar Albino Rats

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Advances in Reproductive Sciences 2024年第1期12卷 1-13页

作者： Mama Sy Racha Kamenda Ibondou Fatoumata Bah robert Foko Ndiaga Diop Mame vénus Abdoulaye Séga Cheikh Diop Mamadou Fall Oumar Faye Laboratory of Histology Embryology and Cytogenetics Faculty of Medecine Cheikh Anta Diop University Dakar Senegal

Introduction: Inappropriate and excess vitamin supplementation, particularly for vitamin A, is increasingly recognized as a public health problem in developed countries. On the other hand, blind supplementation of vitamin A, for children in developing countries is a subject of controversy in the literature. The crucial role of vitamin A in the process of spermatogenesis in adult rodents is well established, but only a few publications are consecrated to the long-term effect of vitamin A intake at a young age on testicular development and differentiation. Objectives: Our study aimed to evaluate the long-term effects of acute supplementation at an early age, in the post-natal period, on spermatogenesis and testicular trophicity at adult age. Material and Methods: Young Wistar Albinos rats of 22 days received an acute high dose of supplementation of vitamin A (retinyl palmitate). The control group, group 1, received only extra virgin olive oil, Group 2 a dose of 7000 IU/kg of retinyl palmitate, group 3, 14,000 IU/kg, and Group 4 a dose of 28,000 IU/kg. At 10 weeks of age, the testes’ testosterone levels were measured by ELISA. For histological assessment, sections were stained with Hematoxylin eosin, and the Johnsen score was used to evaluate spermatogenesis in the seminiferous tubules. Results: The average testicular weights of rats were significantly lower in group 4 (p vel in the testis compared to the control group (p .01). Most of the seminiferous tubules were concerned by an arrest of spermatogenesis and the Johnsen score was decreased with a mean score of 5.96 ± 1.60 (p .001) in that Group. In Group 3, Johnsen’s score was significantly better than the one obtained with the control. Conclusion: We observed a negative effect in the long term with a high acute dose of supplementation of retinyl palmitate at a young age, on testicular development and differentiation. Despite a return to normal diet after that supplementation, d

关键词： vitamin A Retinyl Palmitate Spermatogenesis Testis-Wistar Albino Rats

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Global prevalence and gender inequalities in at least 60 min of self-reported moderate-to-vigorous physical activity 1 or more days per week:An analysis with 707,616 adolescents

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Journal of Sport and Health Science 2024年第5期13卷 709-716页

作者： Raphael H.O.Araujo AndrúO.Werneck Clarice L.Martins Luciana L.Barboza Rafael M.Tassitano Nicolas Aguilar-Farias Gilmar M.Jesus Robinson Ramírez-véelez Riki Tesler Adewale L.Oyeyemi Ellen C.M.Silva robert G.Weaver Mark S.Tremblay Javier Brazo-Sayavera Grégore I.Mielke Danilo R.P.Silva Graduation Program in Health Sciences Londrina State University(UEL)Londrina 86057-970Brazil Center for Epidemiological Research in Nutrition and Health Department of NutritionSchool of Public HealthUniversidade de Sao Paulo(USP)Sao Paulo 01246-904Brazil Department of Physical Education Federal University of ParaıbaParaıba 58051-900Brazil Research Centre of Physical Activity Health and LeisureFaculty of SportsLaboratory for Integrative and Translational Research in Population Health(ITR)University of PortoPorto 4500Portugal Postgraduate Program in Physical Education University of BrasıliaBrasılia 70910-900Brazil Department of Kinesiology and Community Health University of Illinois at Urbana-ChampaignChampaignIL 61801-3841USA Department of Physical Education Sports and RecreationUniversidad de La FronteraTemuco 4680000Chile Department of Health State University of Feira de SantanaFeira de Santana 44036-900Brazil Navarrabiomed Hospital Universitario de Navarra(HUN)Navarra Institute for Health Research(IdiSNA)Universidad Publica de Navarra(UPNA)Pamplona 31006Spain Facultad de Ciencias de la Educacion Unidad Central del Valle del Cauca(UCEVA)TuluaValle del Cauca 763022Colombia Health Management Department Faculty of Heath sciencesAriel UniversityAriel 40700Israel College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Arnold School of Public Health University of South CarolinaColumbiaSC 29208USA Healthy Active Living and Obesity Research Group Children’s Hospital of Eastern Ontario Research InstituteOttawaON K1H 8L1Canada Department of Pediatrics University of OttawaOttawaON K1H 8L1Canada Department of Health Sciences Carleton UniversityOttawaON K1S 5B6Canada Department of Sports and Computer Science Universidad Pablo de Olavide(UPO)Seville 41013Spain Centro Universitario Regional Noreste Universidad de la RepublicaRivera 40000Uruguay School of Public Health The University of QueenslandBrisbaneQLD 4006Australia Department of Physical Education

Background:Guidelines recommend that adolescents should accumulate an average of 60 min per day of moderate-to-vigorous physical activity(MvPA).However,using only this cut-off could hide important *** instance,from a population-level point of view,increasing physical activity for those with no or low physical activity could provide more health benefits than increasing physical activity for those with intermediate ***,including a more sensitive cut-point of≥1 days per week could be an additional strategy for identifying those with low access/opportunities for physical activity ***,the current study aims to estimate the prevalence of≥60 min of MvPA≥1 days per week among adolescents globally,and to describe any relevant gender ***:We used representative datasets from 146 countries/territories collected between 2003 and *** was *** were grouped into younger(≤14 years old)and older(>14 years old)*** Poisson regression models were used to identify the relative differences in≥60 min of MvPA≥1 days per week between boys and girls,and random-effects meta-analysis models were used to identify the pooled *** were stratified by country and ***:Approximately 80%of both younger and older adolescents reported≥60 min of MvPA≥1 days per *** prevalence was≥94%in Europe and Central Asia and North America,while the estimates for the other regions werevalence of≥60 min of MvPA≥1 days per week was higher among boys than girls,with the largest differences occurring among the oldest adolescents(Prevalence ratio_(≤14y)=1.04(95%confidence interval(95%CI)):1.03-1.04)*** ratio_(>14y)=1.09(95%CI:1.08-1.10)).Conclusion:Approximately 8 out of 10 adolescents reported accumulating≥60 min of MvPA≥1 days per week,with notable differences between *** differences were observed in several countries,especially among the oldest *** fo

关键词： Global School-based Student Health Survey Health Behaviour Among School-aged Children survey Inequality Surveillance Youth

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Progress toward understanding the contribution of alkali generation in dental biofilms to inhibition of dental caries

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International Journal of Oral Science 2012年第3期4卷 135-140页

作者： Ya-Ling Liu Marcelle Nascimento robert A burne Depa rtment of Oral Biology College of Dent stry University of Florida Gainesville USA Department of Restorative Dental Sciences Division of Operative Dentistry College of Dentistry University of Florida Gainesville USA

Alkali production by oral bacteria is believed to have a major impact on oral microbial ecology and to be inibitory to the initiation and progression of dental caries. A substantial body of evidence is beginning to accumulate that indicates the modulation of the alkalinogenic potential of dental biofilms may be a promising strategy for caries control. This brief review highlights recent progress toward understanding molecular genetic and physiologic aspects of important alkali-generating pathways in oral bacteria, and the role of alkali production in the ecology of dental biofilms in health and disease.

关键词： arginine biofilm dental caries microbial ecology urea

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Astrocytes in human central nervous system diseases: a frontier for new therapies

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Signal Transduction and Targeted Therapy 2023年第11期8卷 5233-5269页

作者： Alexei verkhratsky Arthur Butt Baoman Li Peter Illes robert Zorec Alexey Semyanov Yong Tang Michael v.Sofroniew International Joint Research Centre on Purinergic Signalling/School of Health and Rehabilitation Chengdu University of Traditional Chinese MedicineChengduChina Department of Forensic Analytical Toxicology School of Forensic MedicineChina Medical UniversityShenyangChina Faculty of Biology Medicine and HealthThe University of ManchesterManchesterUK Achucarro Centre for Neuroscience IKERBASQUEBasque Foundation for ScienceBilbaoSpain Department of Stem Cell Biology State Research Institute Centre for Innovative MedicineLT-01102VilniusLithuania Institute of Biomedical and Biomolecular Sciences School of Pharmacy and Biomedical SciencesUniversity of PortsmouthPortsmouthUK Rudolf Boehm Institute for Pharmacology and Toxicology University of Leipzig04109LeipzigGermany Celica Biomedical Lab Cell EngineeringTechnology Park1000LjubljanaSlovenia Laboratory of Neuroendocrinology—Molecular Cell Physiology Institute of PathophysiologyUniversity of LjubljanaFaculty of MedicineLjubljanaSlovenia Department of Physiology Jiaxing University College of Medicine314033JiaxingChina Key Laboratory of Acupuncture for Senile Disease(Chengdu University of TCM) Ministry of Education/Acupuncture and Chronobiology Key Laboratory of Sichuan ProvinceChengduChina Department of Neurobiology David Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA

Astroglia are a broad class of neural parenchymal cells primarily dedicated to homoeostasis and defence of the central nervous system(CNS).Astroglia contribute to the pathophysiology of all neurological and neuropsychiatric disorders in ways that can be either beneficial or detrimental to disorder *** changes in astroglia can be primary or secondary and can result in gain or loss of *** respond to external,non-cell autonomous signals associated with any form of CNS pathology by undergoing complex and variable changes in their structure,molecular expression,and *** addition,internally driven,cell autonomous changes of astroglial innate properties can lead to CNS *** pathophysiology is complex,with different pathophysiological cell states and cell phenotypes that are context-specific and vary with disorder,disorder-stage,comorbidities,age,and ***,we classify astroglial pathophysiology into(i)reactive astrogliosis,(ii)astroglial atrophy with loss of function,(iii)astroglial degeneration and death,and(iv)astrocytopathies characterised by aberrant forms that drive *** review astroglial pathophysiology across the spectrum of human CNS diseases and disorders,including neurotrauma,stroke,neuroinfection,autoimmune attack and epilepsy,as well as neurodevelopmental,neurodegenerative,metabolic and neuropsychiatric *** cellular and molecular mechanisms of astroglial pathophysiology represents a new frontier to identify novel therapeutic strategies.

关键词： diseases epilepsy degeneration

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Siwalik plant megafossil diversity in the Eastern Himalayas: A review

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Plant Diversity 2023年第3期45卷 243-264页

作者： Mahasin Ali Khan Sumana Mahato robert A.Spicer Teresa E.v.Spicer Ashif Ali Taposhi Hazra Subir Bera Palaeobotany and Palynology Laboratory Department of BotanySidho-Kanho-Birsha UniversityRanchi RoadPurulia 723104India CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303PR China School of Environment Earth and Ecosystem SciencesThe Open UniversityMilton KeynesMK76AAUK Centre of Advanced Study Department of BotanyUniversity of Calcutta35B.C.RoadKolkata 700019India

The Eastern Himalayas are renowned for their high plant *** understand how this modern botanical richness formed,it is critical to investigate past plant biodiversity preserved as fossils throughout the eastern Himalayan Siwalik succession(middle Miocene-early Pleistocene).Here,we present a summary of plant diversity records that document Neogene floristic and climate *** do this by compiling published records of megafossil plant remains,because these offer better spatial and temporal resolution than do palynological *** of the Siwalik floral assemblages based on the distribution of the nearest living relative taxa suggest that a tropical wet evergreen forest was growing in a warm humid monsoonal climate at the deposition *** qualitative interpretation is also corroborated by published CLAMP(Climate Leaf Analysis Multivariate Program) ***,we also reconstruct the climate by applying a new common proxy WorldClim2 *** allows the detection of subtle climate differences between floral assemblages free of artefacts introduced by using different methodologies and climate *** analysis of the Siwalik floras indicates that there was a gradual change in floral *** lower Siwalik assemblages provide evidence of a predominance of evergreen *** increase in deciduous elements in the floral composition is noticed towards the close of the middle Siwalik and the beginning of the upper Siwalik *** change reflects a climatic difference between Miocene and Plio-Pleistocene *** review helps us to understand under what paleoenvironmental conditions plant diversity occurred and evolved in the eastern Himalayas throughout the Cenozoic.

关键词： Megafossils Siwalik MiocenePleistocene Palaeovegetation Palaeoenvironment Eastern Himalayas

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Coryphoid palms from the K-Pg boundary of central India and their biogeographical implications:Evidence from megafossil remains

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Plant Diversity 2023年第1期45卷 80-97页

作者： Sanchita Kumar Taposhi Hazra robert A.Spicer Manoshi Hazra Teresa E.v.Spicer Subir Bera Mahasin Ali Khan Palaeobotany and Palynology Laboratory Department of BotanySidho-Kanho-Birsha UniversityRanchi RoadPurulia 723104India CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303PR China School of Environment Earth and Ecosystem SciencesThe Open UniversityMilton Keynes MK76AAUK Centre of Advanced Study Department of BotanyUniversity of Calcutta35B.C.RoadKolkata 700019India

Ten palm leaf impressions are documented from the latest Maastrichtian(late Cretaceous) to early Danian(earliest Paleocene) sediments(K-Pg,c.66-64 Ma) of the Mandla Lobe of the Deccan Intertrappean Beds,Madhya Pradesh,central *** palmate leaf shape along with a definite wellpreserved costa support their placement in the subfamily Coryphoideae of the family *** place all recovered palm leaf specimens in the fossil genus Sabalites,report seven species of coryphoid palms and describe two new species namely,Sabalities umariaensis *** Sabalites ghughuaensis *** fossils indicate that coryphoid palms were highly diverse in central India by the latest *** and earlier reported coryphoid palm fossils from the same locality indicate that they experienced a warm and humid tropical environment during the time of *** discoveries confirm the presence of a diversity of Coryphoideae in Gondwana prior to the India-Eurasia collision and provide information about coryphoid biogeographical history over geological *** on megafossil remains,we trace coryphoid palm migration pathways from India to mainland Southeast(SE) Asia and other parts of Asia after the docking of the Indian subcontinent with Eurasia early in the Paleogene.

关键词： Coryphoideae Leaf fossils Late cretaceous-early paleocene Paleobiogeography Paleoclimate Madhya Pradesh

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