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A continental back-arc setting for the Namaqua belt:Evidence from the Kakamas Domain

Geoscience Frontiers 2022年第4期13卷 193-221页

作者： P.H.Macey r.j.thomas A.F.M.Kisters j.F.A.Diener M.Angombe S.Doggart C.A.Groenewald C.W.Lambert j.A.Miller H.Minnaar H.Smith H.F.G.Moen E.Muvangua A.Nguno G.Shifotoka j.Indongo D.Frei C.Spencer P.le roux r.A.Armstrong C.Tinguely Council for Geoscience P.O.Box 572BellvilleSouth Africa Department of Geology University of StellenboschSouth Africa Department of Geological Sciences University of Cape TownSouth Africa Geological Survey of Namibia WindhoekNamibia Department of Geology University of Free StateSouth Africa Department of Earth Sciences University of the Western CapeSouth Africa The Institute of Geoscience research Dept.Applied GeologyCurtin UniversityPerthAustralia Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonCanada Geochronology and Tracers Facility British Geological SurveyNottingham NG125GGUK rSES Australian NationalUniversityCanberraACTAustralia

A study of the NW Kakamas Domain in South Africa/Namibia provides a new,unified lithostratigraphy and evolutionary history applicable to the whole Namaqua *** Mesoproterozoic history ranges from~1350 Ma to 960 Ma,but isotopic evidence suggests it was built upon pre-existing Paleoproterozoic continental crust that extended west from the Archaean *** eastern Namaqualand,early rift-related magmatism and sedimentation at~1350 Ma occurred in a confined ocean *** tectonic reversal and subduction at~1290–1240 Ma led to establishment of the Areachap,Konkiep and Kaaien *** the Kakamas Domain,widespread deposition of pelitic sediments occurred at~1220 Ma(Narries Group).These contain detrital zircons derived from proximal crust with ages between~2020 Ma and 1800 Ma(western Palaeoproterozoic domains)and 1350–1240 Ma(eastern early Namaqua domains),suggesting pre-sedimentation *** pelites underwent granulite grade metamorphism at~1210 Ma(peak conditions:4.5–6 kbar and 770–850°C),associated with voluminous,predominantly S-type granitoid orthogneisses between~1210 Ma and 1190 Ma(Eendoorn and Ham river Suites)and low-angle ductile(D_(2))deformation which continued until~1110 Ma,interspersed with periods of *** enduring P-T regime is inconsistent with the expected crustal over-thickening associated with the generally-accepted collision-accretion Namaqualand ***,we propose the Namaqua Sector is a‘hot orogen’developed in a wide continental back-arc with subduction west of the present-day *** observed high geotherm resulted from thinned back-arc lithosphere accompanied by an influx of mantle-derived *** D_(2)deformation resulted from"bottom-driven"tectonics and viscous drag within the crust by convective flow in the underlying asthenospheric *** extended tectonothermal regime ceased at~1110 Ma when SW-directed thrusting stacked the Namaqua Domains into their current positions,constrained in

关键词： Kakamas Namaqua Geodynamics Geochronology Hot orogeny Mesoproterozoic

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Multiple origins of charnockite in the Mesoproterozoic Natal belt,Kwazulu-Natal,South Africa

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Geoscience Frontiers 2012年第6期3卷 755-771页

作者： G.H.Grantham P.Mendonidis r.j.thomas M.Satish-Kumar Central regions Unit Council for GeoscienceP/Bag X112Pretoria 0127South Africa Vaal University of Technology Andries Potgieter BoulevardVanderbijlparkSouth Africa British Geological Survey KeyworthNottingham NG12 5EQ.UK Institute of Geosciences Faculty of Science.Shizuoka University836 OyaSuruga-kuShizuoka 422-8529Japan

Four different varieties of charnockitic rocks, with different modes of formation, from the Mesoproterozoic Natal belt are described and new C isotope data presented. Excellent coastal exposures in a number of quarries and river sections make this part of the Natal belt a good location for observing charnockitic field relationships. Whereas there has been much debate on genesis of charnockites and the use of the term charnockite, it is generally recognized that the stabilization of orthopyroxene relative to biotite in granitoid rocks is a function of low aH2O （-- high CO2）, high temperature, and composition （especially Fe/（Fe ＋Mg））. From the Natal belt exposures, it is evident that syn-emplacement, magmatic crystallization of charnockite can arise from mantle-derived differentiated melts that are inherently hot and dry （as in the Oribi Gorge granites and Munster enderbite）, as well as from wet granitic melts that have been affected through interaction with dry country rock to produce localized charnockitic marginal facies in plutons （as in the Portobello Granite）. Two varieties of post-emplacement sub-solidus charnock- ites are also evident. These include charnockitic aureoles developed in leucocratic, biotite, garnet granite adjacent to cross-cutting enderbitic veins that are attributed to metamorphic-metasomatic processes （as in the Nicholson＇s Point granite, a part of the Margate Granite Suite）, as well as nebulous, patchy charnocki- tic veins in the Margate Granite that are attributed to anatectic metamorphic processes under low-aH2O fluid conditions during a metamorphic event. These varieties of charnockite show that the required physical conditions of their genesis can be achieved through a number of geological processes, providing some important implications for the classification of charnockites, and for the interpretation of charnock- ite genesis in areas where poor exposure obscures field relationships.

关键词： Charnockite igneous Metamorphic Natal belt Dehydration CO2

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Theory and classification of mass extinction causation

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National Science review 2024年第1期11卷 16-36页

作者： thomas j.Algeo jun Shen State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan State Key Laboratory of Geological Processes and Mineral resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(*** flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle *** this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial durin

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

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豆科植物对持续热带草地系统的供氮作用

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国外畜牧学（草原与牧草） 1996年第3期 32-37页

作者： r.j.thomas 魏昭林

一、引言世界总面积的23％或34亿hm^2是永久性草地(FAO,1993),这些草地约有15亿hm^2属于野生或栽培。在大多数热带发展中国家,草地的牲畜生产量较发达国家为低。以牛肉生产量为例,发展中国家每年每头牲畜约为20kg,而发达国家则为96kg(H... 详细信息

一、引言世界总面积的23％或34亿hm^2是永久性草地(FAO,1993),这些草地约有15亿hm^2属于野生或栽培。在大多数热带发展中国家,草地的牲畜生产量较发达国家为低。以牛肉生产量为例,发展中国家每年每头牲畜约为20kg,而发达国家则为96kg(Henzell,1983)。有人认为在南美、非洲、亚洲和澳大利亚。

关键词：草地热带草地豆科植物供氮作用

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豆科牧草在维系草地丰产的氮循环中的作用

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四川草原 1993年第3期 57-63页

作者： r.j.thomas 杜修贵

通过模拟温带和热带地区草地氮循环不同过程的氮流,研究了豆科牧草在不施氮肥的放牧草地氨循环中的作用。对于利用率为10～40％的热带草地来说,在不指望吸收土壤里的有机氮(即无净氮矿化作用)的情况下,据测定,为平衡氮循环,由豆科牧草... 详细信息

通过模拟温带和热带地区草地氮循环不同过程的氮流,研究了豆科牧草在不施氮肥的放牧草地氨循环中的作用。对于利用率为10～40％的热带草地来说,在不指望吸收土壤里的有机氮(即无净氮矿化作用)的情况下,据测定,为平衡氮循环,由豆科牧草固定的氮,必须占牧草地上部份含氮量的38～53％,若以干物质(DM)计,则为20～31％。在放牧强度大,利用率较高。达50～70％的温带草地,不施氮肥时,靠豆科牧草固定的氮需达地上部份含氮量的57～67％,或DM的35～45％,对每个有效的再循环过程(粪尿返还、内部循环或枯落物腐烂分解再代谢)的测试表明,内部循环氮的数量变化,对低水平利用(10～40％)草地的生物固氮量有最大的影响,而利用率较高(70％)的草地,为了平衡循环,返还的粪尿氮的变化,对生物固氮量会产生主要影响。就热带草地而言,要保持3～22t·ha^(-1)·年^(-1)的牧草DM产量,所需要的生物固氮量应为15～158kg ha^(-1)·年^(-1)。集约经营的温带草地,要维持含氮量3.5％的DM产量6～15t ha^(-1)·年^(-1),需要的固氮量为120～352kg ha^(-1)·年^(-1)。这些拟态量表明,豆科牧草在牧草干物质中所占的比例达20～45％,就能维系温带和热带草地的丰产(就N_2而言)。

关键词：牧草豆科牧草氮循环

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Structural effects of reedbed grazing and its cessation on reed-nesting songbird densities

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Avian research 2024年第2期15卷 238-248页

作者： thomas Pagnon Clemence Pechinot Lea Sgro jeremie Demay remi jullian regis Gallais Brigitte Poulin Cyril Marmoex Theria Ecologie 6 avenue des martyrs05400VeynesFrance UMr 6249 Chrono-Environnement CNRSUniversite de Franche-Comte16 route de Gray25000BesanconFrance Conservatoire d’Espaces Naturels d’Occitanie 26 alle de Mycenes34000MontpellierFrance Office Français de la Biodiversite 12 cours Lumiere94300VincennesFrance Tour du Valat research Institute for the Conservation of Mediterranean Wetlands Le Sambuc13200ArlesFrance

reedbeds are crucial breeding habitats for vulnerable songbird *** of their protection status,these habitats may be threatened by organic matter accumulation,progressively leading to structural homoge-nization and habitat succession towards *** prevent excessive litter build-up with various in-terventions opening-up the reedbeds,such as grazing,which may be detrimental or suitable for some reed bird *** assessed the effects of extensive grazing by horses and its cessation in the medium and long terms on reedbed structure,and the consequences on reed-nesting songbird densities in Estagnol Nature reserve,a pro-tected wetland near the French Mediterranean *** compared reedbed structural features between grazed,newly ungrazed and old-ungrazed *** nine years,we censused four songbird species in spring and collected water level data in the same survey *** reduced reedbed extent,rejuvenated the vegetation with more short green stems on a thinner litter,and produced higher structural heterogeneity and discontinuity compared to long-lasting non *** ungrazed plot showed intermediate *** surveyed songbird total densities were similar among plots while species numbers and densities *** reedbed was more attractive to Moustached Warblers(Acrocephalus melanopogon)and Great reed Warblers(Acrocephalus arundi-naceus),likely due to the large edges and the high vegetation structural ***,Moustached Warblers were more negatively affected by higher water level in grazed reedbed,presumably because flooding prevents litter *** newly ungrazed reedbed was not preferred by any *** warbler species were found under low density in the old-ungrazed reedbed,where reed Buntings(Emberiza schoeniclus)were exclu-sively *** availability related to thick litter layer may explain this *** reed Warblers(Acrocephalus scirpaceus)were found everywhere in similar

关键词： Bird conservation Edge complexity Fragmentation Habitat management Horse grazing Phragmites australis reed passerine

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EZH2 inhibitors promote β-like cell regeneration in young and adult type 1 diabetes donors

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Signal Transduction and Targeted Therapy 2024年第2期9卷 679-692页

作者： Keith Al-Hasani Safiya Naina Marikar Harikrishnan Kaipananickal Scott Maxwell jun Okabe Ishant Khurana thomas Karagiannis julia j.Liang Lina Mariana thomas Loudovaris thomas Kay Assam El-Osta Epigenetics in Human Health and Disease Program Baker Heart and Diabetes Institute75 Commercial RoadMelbourne 3004 VICAustralia Department of Diabetes Central Clinical SchoolMonash UniversityMelbourne 3004 VICAustralia Epigenetics in Human Health and Disease Laboratory Central Clinical SchoolMonash UniversityMelbourne 3004 VICAustralia School of Science STEM CollegeRMIT UniversityMelbourne 3001 VICAustralia Immunology and Diabetes Unit St Vincent’s Institute of Medical ResearchFitzroy 3065 VICAustralia Department of Medicine and Therapeutics The Chinese University of Hong KongSha TinHong Kong SAR Hong Kong Institute of Diabetes and Obesity Prince of Wales HospitalThe Chinese University of Hong Kong3/F Lui Che Woo Clinical Sciences Building30-32-Ngan Shing StreetSha TinHong Kong SAR Li Ka Shing Institute of Health Sciences The Chinese University of Hong KongSha TinHong Kong SAR Biomedical Laboratory Science Department of TechnologyFaculty of HealthUniversity College CopenhagenCopenhagenDenmark

β-cells are a type of endocrine cell found in pancreatic islets that synthesize,store and release *** type 1 diabetes(T1D),T-cells of the immune system selectively destroy the insulin-producingβ-*** of these cells leads to a lifelong dependence on exogenous insulin administration for ***,there is an urgent need to identify novel therapies that stimulateβ-cell growth and induceβ-cell *** and others have shown that pancreatic ductal progenitor cells are a promising source for regeneratingβ-cells for T1D owing to their inherent differentiation *** transcriptional suppression is refractory to exocrine reaction and tightly controls the regenerative potential by the EZH2 *** the present study,we show that transient stimulation of exocrine cells,derived from juvenile and adult T1D donors to the FDAapproved EZH2 inhibitors GSK126 and Tazemetostat(Taz)influence a phenotypic shift towards aβ-like cell *** transition from repressed to permissive chromatin states are dependent on bivalent H3K27me3 and H3K4me3 chromatin *** EZH2 is fundamental toβ-cell regenerative *** pancreatic ductal cells exhibit insulin production and secretion in response to a physiological glucose challenge ex *** pre-clinical studies underscore the potential of small molecule inhibitors as novel modulators of ductal progenitor differentiation and a promising new approach for the restoration ofβ-like cell function.

关键词： EZH2 struction inhibitors

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脲醛树脂用水溶性血粉改性

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林业科技通讯 1963年第4期 7-9页

作者： r.j.thomas F.A.Taylor 黄秉端

脲醛树脂在木材加工工业中已经成功地使用了许多年,应用也极广泛。但使用指明:这种树脂在高温下将降低质量,如高温兼高平衡含水率,则这一情况更为加快。一般在120°F—158°F,胶合强度将严重降低;暴露的温度愈高,强度降低愈多。由于脲... 详细信息

脲醛树脂在木材加工工业中已经成功地使用了许多年,应用也极广泛。但使用指明:这种树脂在高温下将降低质量,如高温兼高平衡含水率,则这一情况更为加快。一般在120°F—158°F,胶合强度将严重降低;暴露的温度愈高,强度降低愈多。由于脲醛树脂广泛用于收音机壳、电视机壳等各种产品的制造,这

关键词：血粉胶层水溶性醛树脂改性

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Examining the“revisability”benefit of hip resurfacing arthroplasty

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World journal of Orthopedics 2024年第6期15卷 554-559页

作者： jose George Adam j Taylor thomas P Schmalzried Department of Orthopedics Harbor UCLA Medical CenterTorranceCA 90509United States

BACKGrOUND Hip resurfacing arthroplasty(HrA)is an alternative to total hip arthroplasty(THA)that is typically reserved for young active patients because it preserves ***,the benefits of HrA only hold true if conversion THA after failed HrA provides acceptable *** To compare patient reported outcomes for conversion THA after HrA failure to primary *** A retrospective review of 36 patients(37 hips)that underwent conversion THA for failed HrA between October 2006 and May 2019 by a single surgeon was *** reported outcomes[modified Harris Hip Score(mHHS),University of California Los Angeles(UCLA)activity score]were obtained via an email-based responder-anonymous *** were compared to normative data of a primary THA cohort with similar *** analysis was performed comparing outcomes of conversion THA for adverse local tissue reaction(ALTr)vs all other causes for *** The study group had a lower mHHS than the control group(81.7±13.8 vs 90.2±11.6,Pr,both groups had similar UCLA activity levels(7.5±2.3 vs 7.2±1.6,P=0.51).Patients that underwent conversion for non-ATLr causes had similar mHHS(85.2±11.5 vs 90.2±11.6,P=0.11)and higher UCLA activity levels(8.5±1.8 vs 7.2±1.6,Pred to the control *** that underwent conversion for ATLr had worse mHHS(77.1±14.5 vs 90.2±11.6,Pred to the control *** Patient outcomes equivalent to primary THA can be achieved following HrA conversion to ***,inferior outcomes were demonstrated for ALTr-related HrA *** selection and perhaps further studies examining alternative HrA bearing surfaces should be considered.

关键词： Total hip arthroplasty Hip resurfacing arthroplasty Conversion total hip arthroplasty Adverse local tissue reaction Patient reported outcome measures

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Adeno-associated virus as a delivery vector for gene therapy of human diseases

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1808-1840页

作者： jiang-Hui Wang Dominic j.Gessler Wei Zhan thomas L.Gallagher Guangping Gao Horae Gene Therapy Center University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Department of Microbiology and Physiological Systems University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Centre for Eye research Australia Royal Victorian Eye and Ear HospitalEast MelbourneVIC3002Australia Ophthalmology Department of SurgeryUniversity of MelbourneEast MelbourneVIC3002Australia Department of Neurological Surgery University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Department of Neurosurgery University of MinnesotaMinneapolisMN55455USA Department of Medicine University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Li Weibo Institute for rare Diseases research University of Massachusetts Chan Medical SchoolWorcesterMA01605USA

Adeno-associated virus(AAV)has emerged as a pivotal delivery tool in clinical gene therapy owing to its minimal pathogenicity and ability to establish long-term gene expression in different *** AAV(rAAV)has been engineered for enhanced specificity and developed as a tool for treating various ***,as rAAV is being more widely used as a therapy,the increased demand has created challenges for the existing manufacturing *** rAAV-based gene therapy products have received regulatory approval,but there continue to be concerns about safely using high-dose viral therapies in humans,including immune responses and adverse effects such as genotoxicity,hepatotoxicity,thrombotic microangiopathy,and *** this review,we explore AAV biology with an emphasis on current vector engineering strategies and manufacturing *** discuss how rAAVs are being employed in ongoing clinical trials for ocular,neurological,metabolic,hematological,neuromuscular,and cardiovascular diseases as well as *** outline immune responses triggered by rAAV,address associated side effects,and discuss strategies to mitigate these *** hope that discussing recent advancements and current challenges in the field will be a helpful guide for researchers and clinicians navigating the ever-evolving landscape of rAAV-based gene therapy.

关键词： diseases specificity approval

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