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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(pid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

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

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Experimental investigation of radiative heat propagation in a simplified generic packed bed

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particuology 2024年第5期88卷 149-160页

作者： Matthias Tyslik Lukas pörtner Siegmar Wirtz Martin Schiemann Institute of Energy plant Technology Ruhr-University Bochum44780 BochumGermany

A novel test rig for the investigation of radiative heat transfer in packed beds has been developed and is introduced with representative experimental *** individual components and the calibration are *** generic packed bed is realized in a simplified way by an arrangement of parallel rods,which represent particles in *** this arrangement,electrically heated rods provide the radiation propagating through the rod array to heat the passive counterparts.A sophisticated temperature-control scheme with a large number of thermocouples and infrared-imaging provides in-depth information about heat transfer in the *** radiation intensities are determined with a Fourier-transform infrared spectroscopy,which has been modified and validated for this specific *** order to compare the influence of different surface properties of particles on the heat propagation and surface reflections,rod samples made of stainless steel and magnesium oxide are *** influence of material properties becomes clearly visible by comparing the high radiation intensities resulting from a stainless steel rod array to the same geometry built from magnesium oxide *** addition,the influence of the surface properties is particularly evident in the infrared images since the reflections are significantly higher for the stainless steel samples than for the magnesium oxide *** experimental results in the current work demonstrate the ability of the test rig to provide data with a well-defined accuracy as a validation base for numerical radiation simulations in packed beds.

关键词： Thermal radiation Spectral reflections Fourier-transform infrared spectroscopy

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Outcomes and efficacy of magnetic resonance imaging-compatible sacral nerve stimulator for management of fecal incontinence: A multi-institutional study

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World Journal of Radiology 2024年第2期16卷 32-39页

作者： Binit Katuwal Amy Thorsen Kunal Kochar Ryba Bhullar Ray King ernesto Raul Drelichman Vijay K Mittal Jasneet Singh Bhullar Department of Surgery Ascension Providence HospitalMichigan State University College of Human MedicineSouthfieldMI 48075United States Department of Colon and Rectal surgery Alina Health Abbott Northwestern HospitalMinneapolisMN 55407United States Colon and Rectal Surgery Advocate Illinois MasonicPark RidgeIL 60068United States Volunteer Student Department of ResearchAscension Providence HospitalSouthfieldMI 48075United States Colon and Rectal Surgery University of WisconsinMadisonWI 53715United States General and Colorectal Surgery Ascension Providence HospitalMichigan State University College of Human MedicineSouthfieldMI 48075United States Department of Surgery Department of Medical EducationAscension Providence HospitalMichigan State University College of Human MedicineSouthfieldMI 48075United States

BACKGROUND Fecal incontinence(FI)is an involuntary passage of fecal matter which can have a significant impact on a patient’s quality of *** modalities of treatment exist for *** nerve stimulation is a well-established treatment for *** the increased need of magnetic resonance imaging(MRI)for diagnostics,the In-terStim which was previously used in sacral nerve stimulation was limited by MRI *** MRI-compatible InterStim was approved by the United States Food and Drug Administration in August 2020 and has been widely *** To evaluate the efficacy,outcomes and complications of the MRI-compatible *** Data of patients who underwent MRI-compatible Medtronic InterStim placement at UpMC Williamsport,University of Minnesota,Advocate Lutheran General Hospital,and University of Wisconsin-Madison was pooled and *** demographics,clinical features,surgical techniques,complications,and outcomes were *** the Reporting of Observational studies in Epidemiology(STROBE)cross-sectional reporting guidelines were *** Seventy-three patients had the InterStim *** mean age was 63.29±12.2 ***-seven(78.1%)patients were females and forty-two(57.5%)patients had *** addition to incontinence,overlapping symptoms included diarrhea(23.3%),fecal urgency(58.9%),and urinary incontinence(28.8%).Fifteen(20.5%)patients underwent peripheral Nerve Evaluation before proceeding to definite implant ***-two(43.8%)patients underwent rechargeable InterStim ***(4.1%)patients needed removal of the *** of the external lead connection was observed in 7(9.6%)patients after the stage I *** explanation for one patient was due to ***(9.6%)patients had other complications like nerve pain,hematoma,infection,lead fracture,and *** mean follow-up was 6.62±3.5 ***-eight(93.2%)patients reported significant improvement of symptoms on

关键词： Fecal incontinence Sacral nerve stimulation InterStim Magnetic resonance imaging Sacral neuromodulation

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Non-participation of asymptomatic candidates in screening protocols reduces early diagnosis and worsens prognosis of colorectal cancer

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World Journal of Gastroenterology 2024年第26期30卷 3198-3200页

作者： Sergio pérez-Holanda Office of Regional Viceministry of Health Regional Viceministry of HealthOviedo 33005AsturiasSpain

The Agatsuma et al’s study shows that despite the evidence of the benefits of an early colorectal cancer(CRC)diagnosis,through screening in asymptomatic subjects,up to 50%of candidates reject this option and many of those affected are diagnosed later,in advanced *** efficacy of screening programs has been well-established for several years,which reduces the risk of CRC morbidity and mortality,without taking into account the test used for screening,or other ***,a significant proportion of patients remain unscreened,so understanding the factors involved,as well as the barriers of the population to adherence is the first step to possibly modify the participation *** barriers could include a full range of social and political aspects,especially the type of financial provision of each health *** Japan,health services are universal,and this advantageous situation makes it easier for citizens to access to these services,contributing to the detection of various diseases,including ***,the symptomatic CRC group had a lower early-stage diagnosis rate than the patients detected during follow-up for other comorbidities,and symptomatic and cancer screening groups showed similar early-stage diagnosis.

关键词： Colorectal neoplasms Cancer registry Diagnostic route Cancer screening Stage at diagnosis

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Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese physics B 2024年第2期33卷 108-114页

作者： U.S.Mahabaleshwar G.p.Vanitha L.M.pérez Emad H.Aly I.pop Department of Studies in Mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of Mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

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Unveiling the culprit:the fusobacterium lineage that populates colorectal cancer

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2349-2350页

作者： Johannes Betge Matthias p.Ebert Department of Medicine Ⅱ Medical Faculty MannheimHeidelberg UniversityMannheimGermany Junior Clinical Cooperation Unit Translational Gastrointestinal Oncology and preclinical Models German Cancer Research Center(DKFZ)HeidelbergGermany DKFZ Hector Cancer Institute at University Medical Center MannheimGermany MMpU Microbiota Drug Metabolism and Cancer Therapy European Molecular Biology LaboratoryHeidelbergGermany

In a recent study published in Nature,Zepeda-Rivera et al.1 discovered that one distinct clade of Fusobacterium nucleatum animalis(Fna)dominates the colorectal cancer(CRC)tumor *** work unravels a more precise understanding of a major bacterial species associated with CRC progression,thereby establishing a new focus for future studies,which may aid to develop improved microbiome-based diagnostics and treatments(Fig.1).

关键词： colorectal al. cancer

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palladium-catalyzed S_(N)2 glycosylation of phenols

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Science China Chemistry 2024年第4期67卷 1037-1038页

作者： Yu Zhu p.Andrew Evans Department of Chemistry Queen’s University90 Bader LaneKingstonK7L 3N6Canada Xiangya School of pharmaceutical Sciences Central South UniversityChangsha 410013China

Glycosides are essential structural motifs present in an array of important medicines,materials,and natural products[1].Nevertheless,the chemo-and stereoselective construction of the glycosidic linkage is a long-standing challenge because relatively minor variations in the glycosyl donor or acceptor’s structure can impact stereoselectivity,thus influencing the product's functional properties.

关键词： properties palladium catalyzed

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A Hybrid Machine Learning Approach for Improvised QoE in Video Services over 5G Wireless Networks

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Computers, Materials & Continua 2024年第3期78卷 3195-3213页

作者： K.B.Ajeyprasaath p.Vetrivelan School of Electronics Engineering Vellore Institute of TechnologyChennaiTamil Nadu600127India

Video streaming applications have grown considerably in recent *** a result,this becomes one of the most significant contributors to global internet *** to recent studies,the telecommunications industry loses millions of dollars due to poor video Quality of Experience(QoE)for *** the standard proposals for standardizing the quality of video streaming over internet service providers(ISps)is the Mean Opinion Score(MOS).However,the accurate finding of QoE by MOS is subjective and laborious,and it varies depending on the user.A fully automated data analytics framework is required to reduce the inter-operator variability characteristic in QoE *** work addresses this concern by suggesting a novel hybrid XGBStackQoE analytical model using a two-level layering *** one combines multiple Machine Learning(ML)models via a layer one Hybrid *** ML models at level one are trained using the entire training data *** level two Hybrid XGBStackQoE-Model is fitted using the outputs(meta-features)of the layer one ML *** proposed model outperformed the conventional models,with an accuracy improvement of 4 to 5 percent,which is still higher than the current traditional *** proposed framework could significantly improve video QoE accuracy.

关键词： Hybrid XGBStackQoE-model machine learning MOS performance metrics QoE 5G video services

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Key factors to prioritize when preparing for the Olympic Games

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Journal of Sport and Health Science 2024年第6期13卷 719-721页

作者： George p.Nassis Gregoire p.Millet Department of physical Education College of EducationUnited Arab Emirates UniversityAl Ain 15551United Arab Emirates Institute of Sport Sciences University of LausanneLausanne 1015Switzerland

We need more research that will fulfill the needs of athletes and *** is a common statement,highly relevant nowadays only a few weeks before the commencement of the paris 2024 Olympic *** fill this gap,we have identified 6 topics that we feel coaches and athletes would be interested in learning more to optimize their preparation for the *** topics are.

关键词： preparing statement interested

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Hydrothermal treatment of pearl millet grains:Effects on nutritional composition,antinutrients and flour properties

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Grain & Oil Science and Technology 2024年第2期7卷 87-95页

作者： p.prashanth T.Jayasree Joshi Shagolshem Mukta Singh p.Srinivasa Rao Agricultural and Food Engineering Department Indian Institute of Technology KharagpurKharagpurWest Bengal 721302India

pearl millet(pennisetum glaucum)is one of the major millets with high nutritional *** crop exhibits exceptional resilience to drought and high ***,the processing of pearl millet poses a significant challenge due to its high lipid content,enzyme activity,and presence of ***,it becomes imperative to enhance the quality and prolong the shelf life of pearl millet flour by employing suitable *** treatment in the food industry has long been seen as promising due to its potential to reduce microbial load,inactivate enzymes,and improve nutrient *** study aims to investigate the effects of hydrothermal treatment on the quality characteristics of pearl *** independent variables of the study were soaking temperature(35,45,55℃),soaking time(2,3,4 h),and steaming time(5,10,15 min).Treatment conditions had a statistically significant effect on nutrient *** antinutrients like tannins and phytates were reduced by 0.99% to 5.94% and 0.36% to 6.00%,respectively,after the *** activity decreased significantly up to 10% with the treatment *** findings of this study could potentially encourage the use of pearl millet flour in the production of various food items and promote the application of hydrothermal treatment in the field of food processing.

关键词： pearl millet Hydrothermal treatment Nutritional properties Antinutrients

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