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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(

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

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Soil security and global food security

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 297-302页

作者： david R.MONTGOMERY Department of Earth and Space Sciences University of Washington townSeattleWA 98105USA

Over the course of the postglacial period has managed to add degrade a substantial portion of the world's potential agricultural land. The soil loss and degradation that has repeatedly impacted regional societies around the world resulted from agricultural practices that increased the physical loss of soil(erosion), reduced soil organic matter, changed p H(acidification) or salinity,and disrupted or altered communities of soil life. In the coming century, as continued soil degradation threatens global food security while the global population keeps rising it is imperative that farmers develop and adopt soilhealth building(regenerative) practices to solve a problem that has plagued societies throughout history. Growing evidence suggests that agricultural systems that combine cover crops, reduced tillage, and diverse crop rotations can reduce erosion, enhance soil health and rebuild soil organic matter to cultivate beneficial soil life and harvest both economic and environmental benefits. In the coming post-oil world, global food security would benefit from a global effort to promote soil restoration to help addresses the challenge of sustainably feeding the world, increase soil-based carbon sequestration,protect on-farm biodiversity and reduce off-farm water pollution. Because soil security sets a solid foundation for global food security, agricultural policies and subsidies should be reformed to encourage farmers to adopt regenerative,soil-building practices.

关键词： Agriculture soil security food security regenerative

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Simplified prediction models for acoustic installation effects of train-mounted equipment

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Railway Engineering Science 2024年第2期32卷 125-143页

作者： david Thompson Dong Zhao Giacomo Squicciarini Institute of Sound and Vibration Research University of SouthamptonSouthampton SO171BJUK

Acoustic models of railway vehicles in standstill and pass-by conditions can be used as part of a virtual certification process for new *** each piece of auxiliary equipment,the sound power measured on a test bench is combined with meas-ured or predicted transfer *** is important,however,to allow for installation effects due to shielding by fairings or the train *** the current work,fast-running analytical models are developed to determine these installation *** model for roof-mounted sources takes account of diffraction at the corner of the train body or fairing,using a barrier *** equipment mounted under the train,the acoustic propagation from the sides of the source is based on free-field Green’s *** bottom surfaces are assumed to radiate initially into a cavity under the train,which is modelled with a simple diffuse field *** sound emitted from the gaps at the side of the cavity is then assumed to propagate to the receivers according to free-field Green’s *** show good agreement with a 2.5D boundary element model and with *** uncertainty and parametric uncertainty are *** largest variability occurs due to the height and impedance of the ground,especially for a low *** leads to standard deviations of up to 4 dB at low *** the roof-mounted sources,uncertainty over the location of the corner used in the equivalent barrier model can also lead to large standard deviations.

关键词： Train noise Auxiliary equipment Acoustic installation effects Virtual certification Uncertainty

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Data-Driven Earthquake Multi-impact Modeling: A Comparison of Models

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International Journal of Disaster Risk Science 2024年第3期15卷 421-433页

作者： Hamish Patten Max Anderson Loake david Steinsaltz Information Management International Federation of Red Cross and Red Crescent Societies (IFRC) Department of Statistics University of Oxford

In this study, a broad range of supervised machine learning and parametric statistical, geospatial, and non-geospatial models were applied to model both aggregated observed impact estimate data and satellite image-derived geolocated building damage data for earthquakes, via regression-and classification-based models, respectively. For the aggregated observational data, models were ranked via predictive performance of mortality, population displacement, building damage, and building destruction for 375 observations across 161 earthquakes in 61 countries. For the satellite image-derived data, models were ranked via classification performance(damaged/unaff ected) of 369,813 geolocated buildings for 26 earthquakes in 15 countries. Grouped k-fold, 3-repeat cross validation was used to ensure out-of-sample predictive performance. Feature importance of several variables used as proxies for vulnerability to disasters indicates covariate utility. The 2023 Türkiye–Syria earthquake event was used to explore model limitations for extreme events. However, applying the AdaBoost model on the 27,032 held-out buildings of the 2023 Türkiye–Syria earthquake event, predictions had an AUC of 0.93. Therefore, without any geospatial, building-specific, or direct satellite image information, this model accurately classified building damage,with significantly improved performance over satellite image trained models found in the literature.

关键词： Disaster risk modeling Earthquake impact models Machine learning Disaster statistics Satellite image-derived building damage

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Targeting muscle to treat Charcot-Marie-Tooth disease

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Neural Regeneration Research 2024年第8期19卷 1653-1654页

作者： david Villarroel-Campos James N.Sleigh Department of Neuromuscular Diseases and UCL Queen Square Motor Neuron Disease Centre UCL Queen Square Institute of NeurologyUniversity College LondonLondonUK UK Dementia Research Institute University College LondonLondonUK

Charcot-Marie-Tooth disease(CMT)is a hereditary peripheral neuropathy causing muscle weakness/wasting and sensory dysfunction predominantly in limb *** patients display gait abnormalities,foot deformities,loss of sens... 详细信息

关键词： Marie sensation neuropathy

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Cultivating potential:Harnessing plant stem cells for agricultural crop improvement

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Molecular Plant 2024年第1期17卷 50-74页

作者： Penelope Lindsay Kyle W.Swentowsky david Jackson Cold Spring Harbor Laboratory Cold Spring HarborNY 11724USA National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhanHubei430070China

Meristems are stem cell-containing structures that produce all plant organs and are therefore important targets for crop *** regulators control the balance and rate of cell divisions within the *** these regulators impacts meristem architecture and,as a consequence,plant *** this review,we discuss genes involved in regulating the shoot apical meristem,inflorescence meristem,axillary meristem,root apical meristem,and vascular cambium in *** highlight several examples showing how crop breeders have manipulated developmental regulators to modify meristem growth and alter crop traits such as inflorescence size and branching *** transformation techniques are another innovation related to plant meristem research because they make crop genome engineering *** discuss recent advances on plant transformation made possible by studying genes controlling meristem ***,we conclude with discussions about how meristem research can contribute to crop improvement in the coming decades.

关键词： meristem crop improvement plant transformation plant breeding crop yield gene editing

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Loss to Specialized Cardiology Follow-Up in Adults Living with Congenital Heart Disease

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Congenital Heart Disease 2024年第1期19卷 49-63页

作者： Cheryl Dickson Danielle Osborn david Baker Judith Fethney david S.Celermajer Rachael Cordina Department of Cardiology Royal Prince Alfred HospitalSydneyAustralia Department of Cardiothoracic Surgery Westmead HospitalSydneyAustralia Susan Wakil School of Nursing and Midwifery The University of SydneySydneyAustralia Sydney Medical School The University of SydneySydneyAustralia

Background:Much has been written about the loss to follow-up in the transition between pediatric and adult Congenital Heart Disease(CHD)care *** less is understood about the loss to follow-up(LTF)after a successful *** is critical too,as patients lost to specialised care are more likely to experience mor-bidity and premature ***:To understand the prevalence and reasons for loss to follow-up(LTF)at a large Australian Adult Congenital Heart Disease(ACHD)***:Patients with moderate or highly complex CHD and gaps in care of>3 years(deﬁned as LTF)were identiﬁed from a comprehensive ACHD *** telephone interviews examined current care and barriers to clinic ***:Overall,407(22%)of ACHD patients(n=1842)were *** mean age at LTF was 31(SD 11.5)years and 54%were male;311(76%)were *** to adults seen regularly,lost patients were younger,with a greater socio-economic disadvantage,and had less complex CHD(p<0.05 for all).We interviewed 59 patients(14%).The top 3 responses for care absences were“feeling well”(61%),losing track of time(36%),and not needing fol-low-up care(25%).Conclusions:A large proportion of the ACHD population becomes lost to specialised cardiac care,even after a successful *** Australian study reports younger age,moderate complexity defects,and socio-economic disadvantage as predictive of loss to *** study highlights the need for novel approaches to patient-centered service delivery even beyond the age of transition and resources to maintain patient engagement within the ACHD service.

关键词： Loss to follow-up follow-up adult congenital heart disease lapse in care gaps in care care gaps care continuity ACHD predictors

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Gastroesophageal reflux following peroral endoscopic myotomy for achalasia:Bumps in the road to success

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World Journal of Gastroenterology 2024年第29期30卷 3461-3464页

作者： david Itskoviz Stephen david Howard Malnick Kaplan Medical Center Institute of Gastroenterology and HepatologyHebrew University Medical School of JerusalemRehovot 76100Israel Kaplan Medical Center Department of Internal Medicine CHebrew University Medical School of JerusalemRehovot 76100Israel

Achalasia can significantly impair the quality of *** clinical presentation typically includes dysphagia to both solids and liquids,chest pain,and *** can be delayed in patients with atypical presentations,and they might receive a wrong diagnosis,such as gastroesophageal reflux disease(GERD),owing to overlapping symptoms of both *** the cause of achalasia is poorly understood,its impact on the motility of the esophagus and gastroesophageal junction is well *** treatment modalities have been utilized,with the most common being surgical Heller myotomy with concomitant fundoplication and pneumatic balloon ***,peroral endoscopic myotomy(POEM)has gained popularity as an effective treatment for achalasia,despite a relatively high incidence of GERD occurring after treatment compared to other *** magnitude of post-POEM GERD depends on its definition and is influenced by patient and procedure-related *** longterm sequelae of post-POEM GERD are yet to be determined,but it appears to have a benign course and is usually manageable with clinically available *** risk factors for post-POEM GERD and modifying the POEM procedure in selected patients may improve the overall success of this technique.

关键词： Achalasia Per-oral endoscopic myotomy Gastroesophageal reflux Pneumatic dilatation Heller myotomy Proton pump inhibitor Acidic fermentation

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Origins of perturbations in dayside equatorial ground magnetograms

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Earth and Planetary Physics 2024年第1期8卷 215-221页

作者： Syau-Yun W.Hsieh david G.Sibeck The Johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA NASA Goddard Space Flight Center GreenbeltMarylandUSA

To determine the cause(s)of perturbations seen in dayside equatorial ground magnetograms,we conducted a systematic survey of simultaneous ground-based and geosynchronous satellite-based observations during the 90-day period from December 1,2020 to February 28,*** examined Huancayo ground magnetometer observations from 14:00:00 to 20:00:00 UT each day,during which Huancayo passed through local *** those data we chose perturbation events selected on the basis of large(>20 nT)event amplitude and classified the selected events as responding primarily to solar wind pressure,or to variations in the north/south component of the interplanetary magnetic field(IMF Bz),or perhaps in part to *** results show that an equivalent number of events were identified for each model during this 90-day *** in the lagged solar wind dynamic pressure routinely correspond to nearly simultaneous sudden impulses recorded at both geosynchronous orbit and on the *** in IMF Bz produce erosion signatures at geosynchronous orbit and can correspond to ground events if lag times for reconnection to enhance convection in the magnetosphere are taken into account.

关键词： dayside magnetosphere dayside equatorial ionosphere geosynchronous magnetic field

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A review of therapeutic agents for breast cancer with potentially radiosensitizing properties

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Radiation Medicine and Protection 2024年第2期5卷 75-82页

作者： Zhongwei Zhang david Lim Zhihui Feng Department of Occupational Health and Occupational Medicine School of Public HealthCheeloo College of MedicineShandong UniversityJinan 250012China Centre for Improving Palliative Aged and Chronic Care Through Clinical Research and TranslationFaculty of HealthUniversity of Technology SydneyNSW2007Australia

Breast cancer is the most frequently diagnosed malignant tumor in women worldwide and the leading cause of cancer *** for breast cancer is readily accepted and widely used in clinical *** limitations with radiotherapy include treatment resistance,side effects,and complications caused by high doses of *** search has been on to locate an efficacious *** review summarizes six currently approved pharmaceuticals that have also been investigated for off-label use as radiosensitizers in breast cancer.

关键词： Breast cancer Radiotherapy Radiosensitizer Therapeutic agents

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