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Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： David j.Bottj.r Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory j.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Degradation and resynthesis of chlorophyll during increased oxidative stress and prolonged darkness differ between annual and perennial flax(Linum L.)

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Oil Crop Science 2024年第2期9卷 121-130页

作者： Kenyon j. Nisbett Abida Alokozai Su Hyun Elizabeth Ko G. Adam Mott j.son C.L. Browna Department of Biological Sciences University of Toronto ScarboroughTorontoONCanada Department of Cell&Systems Biology University of TorontoTorontoONCanada Centre for the Analysis of Genome Evolution&Function University of TorontoTorontoONCanada

Among plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 *** proposed by the Disposable Soma Theory,this lifespan variation among plants likely reflects differential investment of limited energy and nutrient resources,with perennials investing more energy and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple *** differential investment may be particularly important during periods of exogenous stress,which are known to accelerate biomolecular *** present study evaluated this hypothesis using annual and perennial flax(Linum L.)subj.cted to two exogenous stressors—increased oxidative stress(i.e.,foliar H2O2spraying)and complete prolonged *** chlorophyll has been shown to exhibit degradation in response to changes in environmental conditions,we utilized changes in chlorophyll levels during and after periods of exogenous stress to evaluate our *** predicted that i)perennials would exhibit a slower rate of chlorophyll degradation during exposure to exogenous stressors compared to annuals,and ii)perennials would exhibit a faster rate of chlorophyll resynthesis following such exposure compared to *** levels before,during,and after exposure to both exogenous stressors were measured in two separate trails,once using image colour analysis and once using *** chlorophyll degradation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following such exposure were significantly higher in perennials,as *** plants were subj.cted to complete prolonged darkness,chlorophyll degradation rates were significantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,ch

关键词： Ageing Life history Maximum lifespan Oxidative stress Somatic maintenance

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A Modified Lagrange Method for Solving Convex Quadratic Optimization Problems

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Open j.urnal of Optimization 2024年第1期13卷 1-20页

作者： Twum B. Stephen Avoka j.hn Christian j. Etwire School of Mathematical Science C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana Department of Mathematics University for Development Studies Tamale Ghana

In this paper, a modified version of the Classical Lagrange Multiplier method is developed for convex quadratic optimization problems. The method, which is evolved from the first order derivative test for optimality of the Lagrangian function with respect to the primary variables of the problem, decomposes the solution process into two independent ones, in which the primary variables are solved for independently, and then the secondary variables, which are the Lagrange multipliers, are solved for, afterward. This is an innovation that leads to solving independently two simpler systems of equations involving the primary variables only, on one hand, and the secondary ones on the other. Solutions obtained for small sized problems (as preliminary test of the method) demonstrate that the new method is generally effective in producing the required solutions.

关键词： Quadratic Programming Lagrangian Function Lagrange Multipliers Optimality Conditions Subsidiary Equations Modified Lagrange Method

Diagnostic Dilemma of Intracardiac Mass: Tumor versus Thrombus-Case Series and Systematic Review

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j.urnal of Biosciences and Medicines 2024年第7期12卷 141-150页

作者： Indira Acharya Ashik Pokharel Raktim Ghosh Christopher j. Haas Department of Internal Medicine Internal Medicine Residency Program Medstar Health Baltimore MD USA Department of Cardiology MedStar Union Memorial Hospital MedStar Health Baltimore MD USA School of Medicine Georgetown University Washington D.C. USA

Background: The differential diagnosis for intracavitary cardiac masses is limited, typically including vegetations, tumors, or thrombi. Cardiac thrombi can often mimic cardiac tumors on imaging, creating a diagnostic challenge. Primary cardiac tumors are rare and usually benign, whereas most cardiac tumors result from metastases, commonly originating from malignancies in the breast, lung, or melanoma. Aim: This report highlights the importance of distinguishing various cardiac masses based on clinical presentations, clinical courses, and radiological features. Case Presentation: We describe two cases of cardiac masses with unique and diverse clinical features. Each case posed significant diagnostic challenges due to their distinct presentations and clinical progressions. Conclusion: These cases underscore the importance of considering both benign and metastatic origins in the differential diagnosis of intracavitary cardiac masses. Accurate differentiation between thrombi and tumors is crucial for appropriate management and treatment.

关键词： Echocardiography Cardiac Masses Arrhythmias Cardiac Magnetic Resonance Imaging Cardiac Thrombi

Necrotic enteritis and antibiotic-free production of broiler chickens:Challenges in testing and using alternative products

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Animal Nutrition 2024年第1期16卷 288-298页

作者： Robert j.Moore School of Science RMIT University

The global trend towards raising broiler chickens without the use of in-feed antibiotics(IFAs) means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously provided. IFAs supported the productivity performance of chickens and played a key role in maintaining their health. Necrotic enteritis(NE) is an important disease of broilers that affects health,productivity, and welfare, and was previously well controlled by IFAs. However, with the reduction in IFA use, NE is resurgent in some countries. Vaccines and various feed additives, including pre-, pro-, and postbiotics, phytobiotics, fatty acids, and phage therapies have been introduced as alternative methods of NE control. While some of these feed additives have specific activity against the NE pathogen, Clostridium perfringens, most have the more general goal of reinforcing gut health. Extensive reviews of the effects of many of these feed additives on gut health have been published recently. Hence, rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative NE treatments and translating laboratory research to real world commercial production settings. The review is based on the author's particular experience,reading, thoughts, and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these issues. It is put forward to stimulate thinking and discussion on the issues covered.

关键词： Necrotic enteritis Clostridium perfringens Vaccines Feed additive Farm management

Decoding the genetic program of micronucleus formation: linking chromosomal instability to human disease

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2840-2842页

作者： j.rg Fahrer Division of Food Chemistry and Toxicology Department of ChemistryRPTU Kaiserslautern-Landau67663 KaiserslauternGermany

A recent study by Adams and colleagues published in Nature unveiled more than one hundred genes that are involved in micronucleus formation,1 which is a biomarker for genomic instability and associated with aging,cancer,and other disorders.2 As an outstanding achievement,the authors identified DSCC1(DNA Replication And Sister Chromatid Cohesion 1)as a critical gene protecting against early developmental defects,genomic instability,reduced proliferative capacity,cohesinopathy-related phenotypes,and tumor development in vivo.

关键词： chromosomal linking Replication

Water Vapor Information from Satellite and Its Applications

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Advances in Atmospheric Sciences 2024年第1期41卷 188-189页

作者： B.j.SOHN School of Earth and Environmental Sciences Seoul National UniversitySeoul 08826Korea

Water vapor is a critical component of the hydrological cycle because it plays a vital role in transporting water from one part of the cycle to *** vapor evaporated from surfaces such as oceans,lakes,and rivers conden... 详细信息

关键词： motion oceans lakes

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SCFD1 in amyotrophic lateral sclerosis: reconciling a genetic association with in vivo functional analysis

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Neural Regeneration Research 2024年第6期19卷 1201-1202页

作者： Ruben j.Cauchi Centre for Molecular Medicine and Biobanking Biomedical Sciences BuildingDepartment of Physiology and Biochemistry Faculty of Medicine and Surgery University of Malta

Amyotrophic lateral sclerosis(ALS) is a neurodegenerative disease characterized by progressive loss of upper and lower motor neurons,resulting in muscle weakness and spasticity,eventually leading to death due to respiratory *** by our group of a casecontrol cohort from an isolated island population have found that genetics plays a significant role in disease etiology(Farrugia Wismayer et al.,2023).

关键词： PROTEIN SLY1