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Possible Relevance of the Allende Meteorite Conditions in Prebiotic Chemistry: An Insight into the Chondrules and Organic Compounds

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Advances in Biological Chemistry 2023年第3期13卷 82-99页

作者： Alejandro Heredia Barbero Héctor G. Vázquez López Adriana L. Meléndez López Jorge A. Cruz Castañeda Daniel Luna Laviada Karina E. Cervantes de la Cruz Victor Meza Laguna Vladimir A. Basiuk Ivonne Rosales Chávez alicia negrón Mendoza Sergio Ramos Bernal Laboratorio de Evolución Química Departamento de Química de Radiaciones y Radioquímica Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México Programa de Posgrado en Ciencias Químicas Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México Departamento de Física Facultad de Ciencias Carrera de Ciencias de la Tierra Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México Departamento de Física de Plasmas e Interacción de Radiación con Materia Instituto de Ciencias Nucleares Ciudad Universitaria Ciudad de México México Departamento de Física y Química Teórica Facultad de Química Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México

The study of the mineral and organic content of the Allende meteorite is important for our understanding of the molecular evolution of the universe as well as the ancient Earth. Previous studies have characterized the magnetic minerals present in ordinary and carbonaceous chondrites, providing information on the evolution of magnetic fields. The interaction of organic compounds with magnetic minerals is a possible source of chemical diversity, which is crucial for molecular evolution. Carbon compounds in meteorites are of great scientific interest for a variety of reasons, such as their relevance to the origins of chirality in living organisms. This study presents the characterization of organic and mineral compounds in the Allende meteorite. The structural and physicochemical characterization of the Allende meteorite was accomplished through light microscopy, powder X-ray diffraction with complementary Rietveld refinement, Raman and infrared spectroscopy, mass spectrometry, scanning electron microscopy, and atomic force microscopy using magnetic signal methods to determine the complex structure and the interaction of organic compounds with magnetic ni-Fe minerals. The presence of Liesegang-like patterns of chondrules in fragments of the Allende structure may also be relevant to understanding how the meteorite was formed. Other observations include the presence of magnetic materials and nanorod-like solids with relatively similar sizes as well as the heterogeneous distribution of carbon in chondrules. Signals observed in the Raman and infrared spectra resemble organic compounds such as carbon nanotubes and peptide-like molecules that have been previously reported in other meteorites, making the Mexican Allende meteorite a feasible sample for the study of the early Earth and exoplanetary bodies.

关键词： Allende Meteorite Carbonaceous Chondrite Light Microscopy X-Ray Diffraction with the Rietveld Method Raman Spectroscopy Attenuated Total Reflectance Infrared Spectroscopy Mass Spectrometry Scanning Electron Mi-croscopy Energy Dispersive X-Ray Spectroscopy Magnetic Force Microscopy

A multi-platform analysis of human gingival crevicular fluid reveals ferroptosis as a relevant regulated cell death mechanism during the clinical progression of periodontitis

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International Journal of Oral Science 2024年第2期16卷 265-279页

作者： Alfredo Torres M.Angélica Michea Ákos Végvári Marion Arce Valentina Pérez Marcela Alcota alicia Morales Rolando Vernal Mauricio Budini Roman A.Zubarev Fermín E.González Laboratory of Experimental Immunology&Cancer Faculty of DentistryUniversity of ChileSantiagoChile Department of Conservative Dentistry Faculty of DentistryUniversity of ChileSantiagoChile Division of Chemistry I Department of Medical Biochemistry and BiophysicsKarolinska InstitutetStockholmSweden Periodontal Biology Laboratory Faculty of DentistryUniversidad de ChileSantiagoChile Laboratory of Cellular and Molecular Pathology Institute for Research in Dental SciencesFaculty of DentistryUniversity of ChileSantiagoChile

Ferroptosis is implicated in the pathogenesis of numerous chronic-inflammatory diseases,yet its association with progressive periodontitis remains *** investigate the involvement and significance of ferroptosis in periodontitis progression,we assessed sixteen periodontitis-diagnosed *** progression was clinically monitored over twelve weeks via weekly clinical evaluations and gingival crevicular fluid(GCF)collection was performed for further *** metrics,proteomic data,in silico methods,and bioinformatics tools were combined to identify protein profiles linked to periodontitis progression and to explore their potential connection with *** western blot analyses validated key ***,a single-cell RnA sequencing(scRnA-seq)dataset(GSE164241)for gingival tissues was analyzed to elucidate cellular dynamics during periodontitis *** progression was identified as occurring at a faster rate than traditionally *** samples from progressing and non-progressing periodontal sites showed quantitative and qualitatively distinct proteomic *** addition,specific biological processes and molecular functions during progressive periodontitis were revealed and a set of hub proteins,including SnCA,CA1,HBB,SLC4A1,and AnK1 was strongly associated with the clinical progression status of ***,we found specific proteins-drivers or suppressors-associated with ferroptosis(SnCA,FTH1,HSPB1,CD44,and GCLC),revealing the co-occurrence of this specific type of regulated cell death during the clinical progression of ***,the integration of quantitative proteomic data with scRnA-seq analysis suggested the susceptibility of fibroblasts to *** analyses reveal proteins and processes linked to ferroptosis for the first time in periodontal patients,which offer new insights into the molecular mechanisms of progressive periodontal *** findings may le

关键词： finding progression faster

Templated synthesis of transition metal phosphide electrocatalysts for oxygen and hydrogen evolution reactions

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Journal of Energy Chemistry 2024年第2期89卷 646-669,I0014页

作者： Rose Anne Acedera alicia Theresse Dumlao DJ Donn Matienzo Maricor Divinagracia Julie Anne del Rosario Paraggua Po-Ya Abel Chuang Joey Ocon Laboratory of Electrochemical Engineering(LEE) Department of Chemical EngineeringUniversity of the PhilippinesDilimanQuezon City 1101Philippines Mechanical Engineering University of CaliforniaMercedCA 95343USA Energy Engineering Program College of EngineeringUniversity of the PhilippinesDilimanQuezon City 1101Philippines

Transition metal phosphides(TMPs)have been regarded as alternative hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalysts owing to their comparable activity to those of noble metal-based *** have been produced in various morphologies,including hollow and porous nanostructures,which are features deemed desirable for electrocatalytic *** synthesis routes are often responsible for such *** paper reviews the latest advances and existing challenges in the synthesis of TMP-based OER and HER catalysts through templated methods.A comprehensive review of the structure-property-performance of TMP-based HER and OER catalysts prepared using different templates is *** discussion proceeds according to application,first by HER and further divided among the types of templates used-from hard templates,sacrificial templates,and soft templates to the emerging dynamic hydrogen bubble *** catalysts are then reviewed and grouped according to their ***,prospective research directions for the synthesis of hollow and porous TMP-based catalysts,such as improvements on both activity and stability of TMPs,design of environmentally benign templates and processes,and analysis of the reaction mechanism through advanced material characterization techniques and theoretical calculations,are suggested.

关键词： OER HER Transition metal phosphide Templated synthesis Electrocatalysts

Superior rectus/levator complex in acquired anophthalmic socket repaired with spheric implant—a computed tomography scan and topographic study

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1483-1488页

作者： Shaikha Al Eid Hamad M AlSulaiman Sahar M Elkhamary Osama Al Sheikh alicia Ferrero-Galindo Rajiv Kandekhar Silvana A Schellini Oculoplastic Division King Khaled Eye Specialist HospitalRiyadh 11462Saudi Arabia Radiology Division King Khaled Eye Specialist HospitalRiyadh 11462Saudi Arabia Department of Diagnostic Radiology Mansoura Faculty of MedicineMansoura 35511Egypt University Hospital Rio Hortega Valladolid 47012Spain Research Department King Khaled Eye Specialist HospitalRiyadh 11462Saudi Arabia Ophthalmology Department Medical SchoolState University of Sao PauloBotucatu 18618-687Brazil

AIM:To determine whether the levator palpebrae superioris(LPS)/superior rectus(SR)muscle complex,can influence the position of the upper lid and fornix in acquired anophthalmic ***:This comparative non-randomized and non-interventional study included retrospective data of 21 patients with unilateral acquired anophthalmic sockets repaired with spheric ***-resolution computed tomography(CT)measurements of the LPM/SR muscle complex and clinical topographic position of the upper lid,superior and inferior fornix depth in primary gaze position were *** data were presented as frequency and percentage proportions and quantitative variables comparing the socket measurements with the normal contralateral orbit was statistically analyzed using non-parametric tests considering Pnophthalmic orbits had a significantly shorter LPS length(P=0.01)and significantly thicker SR(P=0.02)than the normal *** was present in anophthalmic sockets but not in normal orbits(P=0.002),while levator function was normal in both(P>0.05,all comparisons).The superior fornix depth was similar in the anophthalmic socket and the contralateral normal orbit(P=0.192)as well the inferior fornix depth(P=0.351).COnCLUSIOn:Acquired anophthalmic sockets repaired with spheric implants have shorter LPS,thicker SR,and more lagophthalmos than normal *** relationship of the LPS and SR with other orbital structures,associated with passive or active forces acting in the final position of the lids and external ocular prosthesis should be further investigated.

关键词： anophthalmic socket spheric implant levator palpebrae superioris superior rectus lagophthalmos fornix depth

Chebyshev polynomial-based Ritz method for thermal buckling and free vibration behaviors of metal foam beams

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 891-910页

作者： n.D.nGUYEn T.n.nGUYEn Faculty of Civil Engineering Ho Chi Minh City University of Technology and EducationHo Chi Minh City 71309Viet Nam Faculty of Engineering and Technology Kien Giang UniversityChau Thanh 92000Viet Nam

This study presents the Chebyshev polynomials-based Ritz method to examine the thermal buckling and free vibration characteristics of metal foam *** analyses include three models for porosity distribution and two scenarios for thermal *** material properties are assessed under two conditions,i.e.,temperature dependence and temperature *** theoretical framework for the beams is based on the higher-order shear deformation theory,which incorporates shear deformations with higher-order *** governing equations are established from the Lagrange equations,and the beam displacement fields are approximated by the Chebyshev *** simulations are performed to evaluate the effects of thermal load,slenderness,boundary condition(BC),and porosity distribution on the buckling and vibration behaviors of metal foam *** findings highlight the significant influence of temperature-dependent(TD)material properties on metal foam beams'buckling and vibration responses.

关键词： Ritz method Chebyshev function buckling vibration metal foam beam higher-order beam theory(HOBT)

Security Vulnerability Analyses of Large Language Models (LLMs) through Extension of the Common Vulnerability Scoring System (CVSS) Framework

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Journal of Software Engineering and Applications 2024年第5期17卷 340-358页

作者： alicia Biju Vishnupriya Ramesh Vijay K. Madisetti School of Cybersecurity and Privacy College of Computing Georgia Institute of Technology Atlanta GA USA

Large Language Models (LLMs) have revolutionized Generative Artificial Intelligence (GenAI) tasks, becoming an integral part of various applications in society, including text generation, translation, summarization, and more. However, their widespread usage emphasizes the critical need to enhance their security posture to ensure the integrity and reliability of their outputs and minimize harmful effects. Prompt injections and training data poisoning attacks are two of the most prominent vulnerabilities in LLMs, which could potentially lead to unpredictable and undesirable behaviors, such as biased outputs, misinformation propagation, and even malicious content generation. The Common Vulnerability Scoring System (CVSS) framework provides a standardized approach to capturing the principal characteristics of vulnerabilities, facilitating a deeper understanding of their severity within the security and AI communities. By extending the current CVSS framework, we generate scores for these vulnerabilities such that organizations can prioritize mitigation efforts, allocate resources effectively, and implement targeted security measures to defend against potential risks.

关键词： Common Vulnerability Scoring System (CVSS) Large Language Models (LLMs) DALL-E Prompt Injections Training Data Poisoning CVSS Metrics

Compression properties of cost-efficient porous expanded clay reinforced AA7075 syntactic foams fabricated by industrial-oriented die casting technology

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China Foundry 2024年第1期21卷 60-70页

作者： İsmail Cem Akgün Çağın Bolat Ali Gökşenli Faculty of Mechanical Engineering Istanbul Technical University34437İstanbulTurkey Faculty of Engineering Samsun University55420SamsunTurkey

In today’s manufacturing industries,hard competition between rival firms makes it compulsory for researchers to design lighter and cheaper machine components due to the megatrends of cost-effectiveness and *** this point,aluminum syntactic foams(ASFs)are new-generation engineering composites and come into the upfront as a *** to their features like low density,sufficient elongation,and perfect energy absorption ability,these advanced foams have been considerably seductive for many industrial sectors *** this study,an industrial-oriented automatic die casting technology was used for the first time to manufacture the combination of AA7075/porous expanded clay(PEC).Micro evaluations(optical and FESEM)reveal that there is a homogenous particle distribution in the foam samples,and inspections are compatible with the other ASF ***,T6 aging heat treatment was operated on one half of the produced foams to explore the probable impact of aging on the compressive *** results show that PEC particles can be an alternative to expensive hollow spheres used in the previous ***,a favorable relationship is ascertained between the aging treatment and mechanical properties such as compression strength and plateau strength.

关键词： die casting porous materials metal matrix sytanctic foams expanded clay compressive deformation

Predicting effects of tunnel throttling of annular freeway vehicular flow by a continuum model

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 733-746页

作者： Zhongmin Huang M.n.Smirnova n.n.Smirnov Zuojin Zhu Faculty of Engineering Science University of Science and Technology of ChinaHefei 230026China Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Faculty of Mechanics and Mathematics Lomonosov Moscow State UniversityMoscow 119992Russia

Fluid flow throttling is common in industrial and building services *** tunnel throttling of vehicular flow is caused by the abrupt number reduction of roadway lane,as the tunnel has a lower lane number than in the roadway normal *** predict the effects of tunnel throttling of annular freeway vehicular flow,a three-lane continuum model is ***Ⅲof the tunnel is completely blocked due to the need of tunnel rehabilitation,*** exists mandatory net lane-changing rate from laneⅢto laneⅡjust upstream of the tunnel entrance,which is described by a model of random number generated through a golden section *** net-changing rate between adjacent lanes is modeled using a lane-changing time expressed explicitly in algebraic *** paper assumes that the annular freeway has a total length of 100 km,a two-lane tunnel of length 2 km with a speed limit of 80 km/*** free flow speeds on lanesⅠ,ⅡandⅢare assumed to be 110,100 and 90 km/h *** on the three-lane continuum model,numerical simulations of vehicular flows on the annular freeway with such a tunnel are conducted with a reliable numerical method of 3rd-order *** results reveal that the vehicular flow has a smaller threshold of traffic jam formation in comparison with the case without tunnel *** fuel consumption can be estimated by interpolation with time averaged grid traffic speed and an assumed curve of vehicle *** vehicle fuel consumption is lane number dependent,distributes with initial density concavely,ranging from 5.56 to 8.00 *** throttling leads to an earlier traffic jam formation in comparison with the case without tunnel throttling.

关键词： Effects of tunnel throttling Vehicle fuel consumption Travel time Threshold of traffic jam formation Continuum model

Towards defining soil quality of Mediterranean calcareous agricultural soils:Reference values and potential core indicator set

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International Soil and Water Conservation Research 2024年第1期12卷 145-155页

作者： Germán A.Durán Daniel Sacristán Edelweis Farrús Jaume Vadell Institut de Recerca i FormacióAgrària i Pesquera de les Illes Balears C/Eusebi Estada14507009PalmaSpain Plant Biology Department University of Valencia46100BurjassotValenciaSpain Soil and Environmental Quality Department Centro de Investigaciones sobre Desertificación-CIDE(CSIC-Universitat de València-Generalitat Valenciana)Carretera Moncada-Náquera km 4.546113MoncadaValenciaSpain Universitat de les Illes Balears Cra.De Valldemossakm 7507122PalmaSpain

To avoid soil degradation,adapt to climate change and comply with the Sustainable Development goals 2030(Un General Assembly),establishing the quality/fertility of the agricultural soils of the Mediterranean region and evaluate how these evolve with time is *** enables adequate management practices to be *** Mediterranean calcareous region has received little attention in this sense,in spite its soil ***,24 different representative calcareous agricultural soils of the Mediterranean region,including the main management strategies of agricultural soils(rainfed and irrigated),were sampled from the island of Mallorca;and their physical,chemical and biological properties *** values obtained for most of the soil characteristics allowed to establish an initial approach to the reference values for the type of calcareous agricultural soils considered,and to clearly distinguish the effect of rainfed or irrigation management practices on soils properties and *** enzyme activities were not stimulated by the irrigation conditions assayed or they were only in dry conditions,suggesting optimum enzyme activities could be obtained when alternating dry and humid soil *** organic carbon,calcium carbonate and active lime revealed of significant importance in the collection of ***,the results obtained clearly indicate the heterogeneity of the region and its implications on the different soil ***,this study could serve as a starting point to adequately establish the quality(fertility)for Mediterranean calcareous agricultural soils and their reference values by conducting further research in this region and including more type of soils.

关键词： Soil fertility Mediterranean agricultural soils Calcareous soils Soil enzymes Soil management