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

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(boreal latitudes

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

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A metabolic signalling role for arginine in liver cancer

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Life Metabolism 2024年第1期3卷 1-3页

作者： david Sokolov Lucas b.Sullivan Human biology Division Fred Hutchinson Cancer CenterSeattleWA 98109United States

In addition to their canonical roles in biosynthetic pathways,metabolites can be active participants in oncogenic signal-ling,but our understanding of these signalling mechanisms is *** a recent article published in Cell,Mossmann et *** a novel signalling role for accumulated arginine in hepato-cellular carcinoma(HCC)mediated by the RNA splicing factor and transcriptional modifier RNA-binding protein 39(RbM39).

关键词： al. incomplete cancer

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Hydrocarbon indication in Rio bonito Formation sandstone:Implication for CO_(2)storage in São Paulo,brazil

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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

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A systematic scoping review of study methodology for randomized controlled trials investigating probiotics in athletic and physically active populations

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Journal of Sport and Health Science 2024年第1期13卷 61-71页

作者： Alex E.Mohr david b.Pyne Geovana Silva Fogaça Leite Deborah Akins Jamie Pugh College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Research Institute for Sport and Exercise University of CanberraCanberraACT 2617Australia Laboratory of Functional Fermented Food Faculty of Pharmaceutical SciencesUniversity of São PauloSão Paulo 05508-030Brazil Research Institute for Sport and Exercise Sciences Liverpool John Moores UniversityLiverpool L33AFUK

background:The purported ergogenic and health effects of probiotics have been a topic of great intrigue among researchers,practitioners,and the lay public *** has also been an increased research focus within the realm of sports science and exercise medicine on the athletic gut ***,compared to other ergogenic aids and dietary supplements,probiotics present unique study *** objectives of this systematic scoping review were to identify and characterize study methodologies of randomized controlled trials investigating supplementation with probiotics in athletes and physically active ***:Four databases(MEDLINE,CINAHL,Cochrane CENTRAL,and Cochrane Database of Systematic Reviews)were searched for randomized controlled studies involving healthy athletes or physically active *** intervention with probiotics and inclusion of a control and/or placebo group were *** peer-reviewed articles in English were considered,and there were no date *** were extracted and presented in tabular form to detail study protocols,characteristics,and *** in randomized controlled trials was determined with the Rob 2.0 ***:A total of 45 studies were included in the review,with 35 using a parallel group design and 10 using a cross-over *** half the studies used a single probiotic and the other half a multi-strain *** probiotic dose ranged from 2×10^(8)to 1×10^(11)colony forming units daily,and the length of intervention was between 7 and 150 *** than half the studies directly assessed gastrointestinal symptoms,gut permeability,or the gut *** sex ratio of participants was heavily weighted toward males,and only 3 studies exclusively investigated ***-level adverse events were reported in only 2 studies,although the methodology of reporting varied *** risk of bias was generally low,although details on randomization were lacking in some s

关键词： Exercise Experimental methodology Gastrointestinal symptoms Gut microbiota Probiotic supplementation

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Rational molecular design of efficient yellow-red dendrimer TADF for solution-processed OLEDs: a combined effect of substitution position and strength of the donors

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Science China Chemistry 2024年第5期67卷 1613-1623页

作者： Changfeng Si Dianming Sun Tomas Matulaitis david b.Cordes Alexandra M.Z.Slawin Eli Zysman-Colman Organic Semiconductor Centre EaStCHEM School of ChemistryUniversity of St AndrewsSt AndrewsKY169STUK

The development of high-performance solution-processed red organic light-emitting diodes(OLEDs) remains a challenge,particularly in terms of maintaining efficiency at high luminance. Here, we designed and synthesized four novel orange-red thermally activated delayed fluorescence(TADF) dendrimers that are solution-processable: 2GCz bP, 2DPACz bP, 2FbP2GCz and 2FbP2DPACz. We systematically investigated the effect of substitution position and strength of donors on the optoelectronic properties. The reverse intersystem crossing rate constant(kRISC) of the emitters having donors substituted at positions 11and 12 of the dibenzo[a,c]phenazine(bP) is more than 10-times faster than that of compounds substituted having donors substituted at positions 3 and 6. Compound 2DPACz bP, containing stronger donors than 2GCz bP, exhibits a red-shifted emission and smaller singlet-triplet energy splitting, ΔE_(ST), of 0.01 e V. The solution-processed OLED with 10 wt% 2DPACz bP doped in m CP emitted at 640 nm and showed a maximum external quantum efficiency(EQE_(max)) of 7.8%, which was effectively maintained out to a luminance of 1,000 cd m-2. Such a device's performance at relevant display luminance is among the highest for solution-processed red TADF OLEDs. The efficiency of the devices was improved significantly by using 4Cz IPN as an assistant dopant in a hyperfluorescence(HF) configuration, where the 2DPACz bP HF device shows an EQEmaxof 20.0% at λEL of 605 nm and remains high at 11.8% at a luminance of 1,000 cd m-2, which makes this device one of the highest efficiency orange-to-red HF SP-OLEDs to date.

关键词： thermally activated delayed fluorescence solution-processing red OLEDs dibenzo[a,c]phenazine dendrimers

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Inflammatory Factor IL1αInduces Aberrant Astrocyte Proliferation in Spinal Cord Injury Through the Grin2c/Ca^(2+)/CaMK2b Pathway

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Neuroscience bulletin 2024年第4期40卷 421-438页

作者： Yu Xia Lu Ding Changlin Zhang Qi Xu Ming Shi Tianshun Gao Feng-Quan Zhou david Y.b.Deng Scientific Research Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Department of Gynecology The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Pelvic Floor Disorders Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China big Data Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Sir Run Run Shaw Hospital Zhejiang University School of MedicineHangzhou310016China Orthopaedic and Neurological Repair Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China

Spinal cord injury(SCI)is one of the most devastating traumas,and the aberrant proliferation of astrocytes usually causes neurological ***,the mechanism underlying astrocyte over-proliferation after SCI is ***2c(glutamate ionotropic receptor type 2c)plays an essential role in cell *** bioinformatic analysis indicated that Grin2c and Ca^(2+)transport functions were inhibited in astrocytes after *** of Grin2c stimulated astrocyte proliferation by inhibiting the Ca^(2+)/calmodulin-dependent protein kinase 2b(CaMK2b)pathway in *** screening different inflammatory factors,interleukin 1α(IL1α)was further found to inhibit Grin2c/Ca^(2+)/CaMK2b and enhance astrocyte proliferation in an oxidative damage *** of IL1αusing neutralizing antibody resulted in increased Grin2c expression and the inhibition of astrocyte proliferation ***,this study suggests that IL1αpromotes astrocyte proliferation by suppressing the Grin2c/Ca^(2+)/CaMK2b pathway after SCI,revealing a novel pathological mechanism of astrocyte proliferation,and may provide potential targets for SCI repair.

关键词： IL1α Grin2c Astrocyte Spinal cord injury

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古新世-始新世极热事件期间的浊积岩沉积对气候变化和天文旋回的响应

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第四纪研究 2024年

作者：金思敏 david b.KEMP 张仲石黄春菊刘晴中国地质大学(武汉)环境学院大气科学系中国地质大学(武汉)地球科学学院生物地质与环境地质国家重点实验室关键带演化湖北省重点实验室

浊流是地表最重要的沉积物运移过程之一,主导了沉积物从大陆架到深海的输送。通过研究深时极热事件期间浊流的分布规律,可为类比推测未来全球变暖背景下浊流活动的变化趋势提供重要参考。前期研究发现,古新世-始新世极热事件(PETM)期间... 详细信息

浊流是地表最重要的沉积物运移过程之一,主导了沉积物从大陆架到深海的输送。通过研究深时极热事件期间浊流的分布规律,可为类比推测未来全球变暖背景下浊流活动的变化趋势提供重要参考。前期研究发现,古新世-始新世极热事件(PETM)期间,英国东部北海盆地的高频浊积砂岩沉积受到了气候变化的影响。本研究进一步对西班牙basque盆地Zumaia剖面古新统-始新统458层浊积岩(深度范围为-19.76～37.12 km)进行了时间序列分析,发现浊积岩沉积存在着显著的405 ka长偏心率周期信号。通过总结古新统-始新统浊积岩记录对天文旋回的响应,发现仅在英国北海盆地和西班牙basque盆地识别出了天文旋回信号,且这两个点位的地理位置与模拟结果显示的年平均降水对轨道参数变化的敏感区相吻合。此外,本研究还讨论了PETM期间不同沉积环境中浊积岩沉积记录对海平面变化和全球升温的响应。

关键词：古新世-始新世极热事件天文旋回浊积岩偏心率岁差

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Decoupling COb>2b> from Climate Change

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International Journal of Geosciences 2024年第3期15卷 246-269页

作者： Michael Nelson david b. Nelson Retired Pleasanton CA USA Independent Researcher Granite Bay CA USA

This study determines if there is a correlation between rising carbon dioxide levels and global warming. Historical data were reviewed from three different time periods spanning 500 million years. It showed that the curves and trends were too dissimilar to establish a connection. Observations from COb>2b>/temp ratios showed that the COb>2b> and the temperature moved in opposite directions 42% of the time. Many ratios displayed zero or near zero values, reflecting a lack of response. As much as 87% of the ratios revealed negative or near zero values, which strongly negate a correlation. The infrared spectra showed the Greenhouse Gases had an exceptionally low absorption band between 11.67 μm to 9.1 μm, which is a zone called the infrared atmospheric window. Most of the Greenhouse Gases absorb little infrared inside that zone. And that zone is where the Earth’s surface emits almost all infrared radiation. Even with minimal absorbance, water vapor captures the most infrared radiation. It absorbs 84 times more than COb>2b>, 407 thousand times more than methane, 452 thousand times more than ozone and 2.3 million times more than nitrous oxide. The Intergovernmental Panel on Climate Change (IPCC) and the United States EPA excluded water vapor because it was not associated with man-made activities. They reported that water vapor and clouds were simply feedback mechanisms from COb>2b>. Clouds reflect radiation from the sun. The Northern Hemisphere is 2.7°F warmer than the Southern Hemisphere because of clouds. The world cloud cover has gone down 4.1% from 1982 to 2018. Calculations show that this could be responsible for 2.4°F of the 2.7°F. The research shows that most of the recent increase in temperature (89.9%) is because of fewer clouds.

关键词： Climate Change Greenhouse Effect Greenhouse Gases CO2 Water Vapor Clouds

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The role of N-glycosylation in cancer

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Acta Pharmaceutica Sinica b 2024年第3期14卷 1098-1110页

作者： Yu Lin david M.Lubman Department of Surgery University of Michigan Medical CenterAnn ArborMI 48109USA

Despite advances in understanding the development and progression of cancer in recent years,there remains a lack of comprehensive characterization of the cancer *** play an important role in medicine and are involved in various human disease conditions including ***-moieties participate in fundamental cancer processes like cell signaling,invasion,angiogenesis,and *** N-glycosylation significantly impacts cancer processes and targeted therapies in ***,understanding N-glycosylation in a tumor is essential for comprehending disease progression and discovering anti-cancer targets and biomarkers for therapy monitoring and *** review presents the fundamental process of protein N-glycosylation and summarizes glycosylation changes in tumor cells,including increased terminal sialylation,N-glycan branching,and ***,the role of N-glycosylation in tumor signaling pathways,migration,and metabolism are *** and glycopeptides as potential biomarkers for early detection of cancer based on site specificity have been ***,understanding and exploring the cancer glycoproteome,along with its role in medicine,implication in cancer and other human diseases,highlights the significance of N-glycosylation in tumor processes,necessitating further research for potential anticancer targets and biomarkers.

关键词： N-Glycosylated proteins Cancer signaling Cancer angiogenesis Cancer metabolism Cancer biomarkers

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The Cloud Model for Climate Change

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International Journal of Geosciences 2024年第5期15卷 366-395页

作者： Michael Nelson david b. Nelson Retired Pleasanton CA USA

In 1995, the Intergovernmental Panel on Climate Change (IPCC) released a thermodynamic model based on the Greenhouse Effect, aiming to forecast global temperatures. This study delves into the intricacies of that model. Some interesting observations are revealed. The IPCC model equated average temperatures with average energy fluxes, which can cause significant errors. The model assumed that all energy fluxes remained constant, and the Earth emitted infrared radiation as if it were a blackbody. Neither of those conditions exists. The IPCC’s definition of Climate Change only includes events caused by human actions, excluding most causes. Satellite data aimed at the tops of clouds may have inferred a high Greenhouse Gas absorption flux. The model showed more energy coming from the atmosphere than absorbed from the sun, which may have caused a violation of the First and Second Laws of Thermodynamics. There were unexpectedly large gaps in the satellite data that aligned with various absorption bands of Greenhouse Gases, possibly caused by photon scattering associated with re-emissions. based on science, we developed a cloud-based climate model that complied with the Radiation Laws and the First and Second Laws of Thermodynamics. The Cloud Model showed that 81.3% of the outgoing reflected and infrared radiation was applicable to the clouds and water vapor. In comparison, the involvement of COb>2b> was only 0.04%, making it too minuscule to measure reliably.

关键词： Climate Change Greenhouse Gas CO2 Clouds Model Thermodynamics

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