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Towards efficient strain engineering of 2D materials:A four-points bending approach for compressive strain

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Nano Research 2024年第6期17卷 5317-5325页

作者： Hao Li Félix Carrascoso Ana Borrás Gloria P.moreno Francisco J.Aparicio Ángel Barranco Andrés Castellanos Gómez Campus de Cantoblanco Instituto de Ciencia de Materiales de MadridC.Sor Juana Inés de la Cruz328049 MadridSpain Nanotechnology on Surfaces and Plasma Lab Instituto de Ciencia de Materiales de Sevilla(CSIC-Universidad de Sevilla).C/Americo Vespucio 49E-41092 SevilleSpain Departamento de Física Aplicada I Escuela Politécnica SuperiorUniversidad de Sevillac/Virgen deÁfrica 7E-41011 SevilleSpain

Strain engineering,as a powerful strategy to tune the optical and electrical properties of two-dimensional(2D)materials by deforming their crystal lattice,has attracted significant interest in recent years.2D materials can sustain ultra-high strains,even up to 10%,due to the lack of dangling bonds on their surface,making them ideal brittle *** remarkable mechanical resilience,together with a strong strain-tunable band structure,endows 2D materials with a broad optical and electrical response upon ***,strain engineering based on 2D materials is restricted by their nanoscale and strain quantification *** this study,we have modified a homebuilt three-points bending apparatus to transform it into a four-points bending apparatus that allows for the application of both compressive and tensile strains on 2D *** approach allows for the efficient and reproducible construction of a strain system and minimizes the buckling effect caused by the van der Waals interaction by adamantane encapsulation *** results demonstrate the feasibility of introducing compressive strain on 2D materials and the potential for tuning their optical and physical properties through this approach.

关键词： uniaxial compressive strain polymer encapsulation differential reflectance spectroscopy exciton tunability

Emerging and multifaceted potential contributions of polyphenols in the management of type 2 diabetes mellitus

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World Journal of Diabetes 2024年第2期15卷 154-169页

作者： Ileana González Cristian Lindner Ivan Schneider Erik Diaz miguel Angel Morales Armando Rojas Biomedical Research Laboratories Faculty of MedicineCatholic University of MauleTalca 34600000Chile Department of Radiology Faculty of MedicineUniversity of ConcepciónConcepción 4030000Chile Centre of Primary Attention South Metropolitan Health ServiceSantiago 3830000Chile Faculty of Medicine Catholic University of MauleTalca 3460000Chile Molecular and Clinical Pharmacology Program Institute of Biomedical SciencesUniversity of ChileSantiago 8320000Chile

Type 2 diabetes mellitus(T2DM)is recognized as a serious public health concern with a considerable impact on human life,long-term health expenditures,and substantial health *** this context,the use of dietary polyphenols to prevent and manage T2DM is widely *** dietary compounds exert their beneficial effects through several actions,including the protection of pancreatic islet β-cell,the antioxidant capacities of these molecules,their effects on insulin secretion and actions,the regulation of intestinal microbiota,and their contribution to ameliorate diabetic complications,particularly those of vascular *** the present review,we intend to highlight these multifaceted actions and the molecular mechanisms by which these plant-derived secondary metabolites exert their beneficial effects on type 2 diabetes patients.

关键词： Polyphenols Antioxidants Oxidative stress Type 2 diabetes mellitus Health benefits

Pancreatic neuroendocrine tumors:Are tumors smaller than 2 cm truly indolent?

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1756-1762页

作者： Sergio Hoyos Pablo Posada.moreno Natalia Guzman-Arango Romario Chanci-Drago Jaime Chavez Alvaro Andrés-Duarte Santiago Salazar-Ochoa Hepatobilary and Liver Transplant Unit Hospital Pablo Tobon Uribe and Gastrohepathology Group Universidad de AntioquiaMedellin 050034AntioquiaColombia Department of General Surgery Universidad Pontificia BolivarianaMedellín 050034AntioquiaColombia

BACKGROUND Pancreatic neuroendocrine tumors(PNETs)are relatively rare but rank as the second most common pancreatic *** can be functional,causing early metabolic disturbances due to hormone secretion,or non-functional and diagnosed later based on tumor size-related *** diagnoses of PNETs under 2 cm in size have sparked debates about their management;some practitioners advocate for surgical removal and others suggest observation due to the tumors’lower potential for ***,it is unclear whether managing these small tumors expectantly is truly *** To evaluate poor prognostic factors in PNETs based on tumor size(>2 cm or<2 cm)in surgically treated *** This cohort study included 64 patients with PNETs who underwent surgical resection between 2006 and 2019 at a high-complexity reference hospital in Medellín,*** assess patient survival,quarterly follow-ups were conducted during the first year after surgery,followed by semi-annual con-sultations at the hospital's hepatobiliary surgery *** variables were described using absolute and relative frequencies,and quantitative variables were expressed using measures of central tendency and their corresponding measures of *** The presence of lymph node involvement,neural involvement,and lymphovascular invasion were all associated with an increased risk of mortality,with hazard ratios of 5.68(95%CI:1.26–25.61,P=0.024),6.44(95%CI:1.43–28.93,P=0.015),and 24.87(95%CI:2.98–207.19,P=0.003),*** involvement and lymphovascular invasion were present in tumors smaller than 2 cm in diameter and those larger than 2 cm in *** recurrence rates between the two tumor groups were furthermore similar:18.2%for tumors smaller than 2 cm and 21.4%for tumors larger than 2 *** survival was additionally comparable between the two tumor *** Tumor size does not dictate prognosis;lymph node and lymphovascular involvement a

关键词： Neuroendocrine tumor Pancreatic neoplasm Pancreas Pancreatic neuroendocrine neoplasm Pancreatic neuroendocrine tumors

The Return of Civilisations

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International Understanding 2024年第1期 20-24页

作者： miguel Angel Moratinos the United Nations

I was pleasantly surprised when visiting the new Louvre Museum in Abu Dhabi,magnificently designed,and created by the great French architect Jean Nouvel to prove the creative force of the world's diverse *** of them a... 详细信息

关键词： looking island creative

Large dinosaur egg accumulations and their significance for understanding nesting behaviour

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Geoscience Frontiers 2024年第5期15卷 467-488页

作者： L.Ezquerro R.Coimbra B.Bauluz C.Núñez-Lahuerta T.Román-Berdiel M.moreno-Azanza Departamento de Geodinámica Estratigrafía y PaleontologíaFacultad de Ciencias GeológicasUniversidad Complutense de MadridC/JoséAntonio Novais1228040MadridSpain Aragosaurus-IUCA:Recursos Geológicos y Paleoambientales.Departamento de Ciencias de la Tierra.Facultad de Ciencias Universidad de ZaragozaC/Pedro Cerbuna 1250009 ZaragozaSpain Museu da Lourinha LourinhaPortugal GeoBioTec Department of Earth SciencesNOVA School of Science and TechnologyUniversidade Nova de LisboaCaparicaPortugal GeoBioTec Departamento de GeocienciasUniversidade de AveiroAveiroPortugal Insitut Catalàde Paleoecologia Humana i EvolucióSocial(IPHES-CERCA) Zona Educacional 4Campus Sescelades URV(Edifici W3)43007 TarragonaSpain Departament d´Història i Història de l´Art Universitat Rovira i VirgiliAv.Catalunya 3543002 TarragonaSpain Geotransfer IUCA Departamento de Ciencias de La TierraFacultad de CienciasUniversidad de ZaragozaZaragozaSpain

The accurate identification of dinosaur egg accumulations as nests or clutches is crucial for understanding the reproductive behaviour of these extinct ***,existing methods often rely on the presence of complete eggs and embryo remains,and sedimentological criteria that are only applicable to well-structured *** this study,we introduce an innovative approach to characterize egg accumulations in structureless sediments,where traditional nest structures may not be *** methodology employs a unique combination of sedimentological,taphonomic,geochemical,and geophysical proxies for the study of egg *** applied this approach to the egg accumulation from Paimogo(Jurassic,Portugal),traditionally interpreted as a *** findings reveal that the Paimogo egg assemblage is a secondary deposit,resulting from a flooding event in a fluvial plain that dismantled several allosauroid and crocodylomorph *** eggshell vapor conductance results,coupled with sedimentological evidence,suggest that allosauroid dinosaurs buried their eggs in the dry terrain of overbank areas close to a main channel during the breeding season,likely during the dry season to prevent the embryos from *** research underscores the necessity of multidisciplinary approaches in interpreting egg accumulations and offers a novel methodology for studying these accumulations in structureless *** findings provide new insights into the breeding behaviour and nesting preferences of these extinct organisms,contributing to our understanding of dinosaur ecology.

关键词： Breeding behaviour Theropod Taphonomy Stable isotopes Magnetic susceptibility Jurassic

Effect of the Density of Molten Metal on the Raining Phenomenon in Horizontal Centrifugal Casting

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Open Journal of Applied Sciences 2024年第7期14卷 1918-1926页

作者： miguel A. Barron Joan Reyes Departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Ciudad de Mexico Mexico

In this work the influence of the density of the molten metal on the emergence of the raining phenomenon in the horizontal centrifugal casting process is numerically studied. Transient 2D numerical simulations were carried out using Computational Fluid Dynamics software. Three molten metals with different density, namely aluminum, iron and lead, and three angular frequencies, namely 50, 66 and 77 rad/s were considered. It is found that the density of the molten metal significantly affects the emergence, transient or permanent, of the rain phenomenon. However, the magnitude and duration of the rain phenomenon depend on the angular frequency of the rotating mold. Likewise, since gravitational forces affect the metal according to its density, the value of the critical rotation speed of the mold is also affected.

关键词： Angular Frequency Centrifugal Force Computational Fluid Dynamics Critical Rotation Speed G Factor Horizontal Centrifugal Casting Molten Metal Density

Oxygen tension modulates cell function in an in vitro three-dimensional glioblastoma tumor model

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Bio-Design and Manufacturing 2024年第3期7卷 307-319页

作者： Sen Wang Siqi Yao Na Pei Luge Bai Zhiyan Hao Dichen Li Jiankang He J.miguel Oliveira Xiaoyan Xue Ling Wang Xinggang Mao State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an 710054China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710054China NMPA Key Laboratory for Research and Evaluation of Additive Manufacturing Medical Devices Xi’an Jiaotong UniversityXi’an 710054China 3B’s Research Group I3Bs–Research Institute on BiomaterialsBiodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3B’s-PT Government Associate Laboratory 4806-909 Braga/Guimar˜aesPortugal Department of Pharmacology School of PharmacyFourth Military Medical UniversityXi’an 710032China Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi’an 710032China

Hypoxia is a typical feature of the tumor microenvironment,one of the most critical factors affecting cell behavior and tumor ***,the lack of tumor models able to precisely emulate natural brain tumor tissue has impeded the study of the effects of hypoxia on the progression and growth of tumor *** study reports a three-dimensional(3D)brain tumor model obtained by encapsulating U87MG(U87)cells in a hydrogel containing type I *** also documents the effect of various oxygen concentrations(1%,7%,and 21%)in the culture environment on U87 cell morphology,proliferation,viability,cell cycle,apoptosis rate,and ***,it compares two-dimensional(2D)and 3D *** comparison purposes,cells cultured in flat culture dishes were used as the control(2D model).Cells cultured in the 3D model proliferated more slowly but had a higher apoptosis rate and proportion of cells in the resting phase(G0 phase)/gap I phase(G1 phase)than those cultured in the 2D ***,the two models yielded significantly different cell ***,hypoxia(e.g.,1%O2)affected cell morphology,slowed cell growth,reduced cell viability,and increased the apoptosis rate in the 3D *** results indicate that the constructed 3D model is effective for investigating the effects of biological and chemical factors on cell morphology and function,and can be more representative of the tumor microenvironment than 2D culture *** developed 3D glioblastoma tumor model is equally applicable to other studies in pharmacology and pathology.

关键词： Hypoxia Glioma Three-dimensional glioma model In vitro

A prototype for on-site generation of chlorinated disinfectant for use in rural aqueducts

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Water Science and Engineering 2024年第1期17卷 33-40页

作者： Diana Marcela Cuesta Parra Felipe Correa Mahecha Andrés Felipe Rubio Pinzon Davidcamilo Ramirez Bustos Leonel Alveyro Teran Llorente miguel Fernando Jimenez Jimenez Chemical and Environmental Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia Chemical Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia Mecanical Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia

Sodium hypochlorite has significant potential as a sanitation solution in hard-to-reach *** studies have investigated the optimal electrolysis parameters for its production with volumes greater than 1o *** study evaluated sodium hypochlorite production through electrolysis in a 22-L prototype and identified the optimal operating *** were performed using graphite electrodes with areas of 68.4 cm^(2) at the laboratory scale and 1865.0 cm^(2) at the prototype scale.A design for experiments with different operating times,chloride concentrations,and electric current intensities was *** optimal operating time,sodium chloride concentration,and current intensity at the laboratory scale were 120 min,150 g of chloride per liter,and 3 A,respectively,leading to the production of 5.02 g/L of the disinfectant with an energy efficiency of 12.21 mg of Cl_(2) per *** the prototype scale,the maximum sodium hypochlorite concentration of 3.99 g of chloride per liter was achieved with an operating time of 120 min,a sodium chloride concentration of 100 g of chloride per liter,and a current intensity of 70 A,reaching an energy efficiency of 42.56 mg of Cl_(2) per *** addition,this study evaluated the influences of the chloride concentration,current intensity,and operating time on the production of sodium hypochlorite at the two scales,and formulated the equations showing the trends of sodium hypochlorite production and energy efficiency in the electrochemical *** 22-L prototype model for production of this oxidizing substance is promising for disinfection of large volumes of water in areas that are difficult to access.

关键词： Disinfection Electrolysis Energy efficiency Optimization Sodium hypochlorite

一种优化开关磁阻电机换相区控制策略的高效率转矩分配函数

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电工技术学报 2024年第6期39卷 1671-1683页

作者：杨帆陈昊李晓东 miguel Pablo Aguirre Muhammad Asghar Saqib 中国矿业大学电气工程学院徐州221116 新能源电动车技术与装备中东欧国家国际联合研究中心徐州221008 江苏省高校新能源发电与电动车国际合作联合实验室徐州221008 徐州市新能源电动车技术与装备重点实验室徐州221008 澳门科技大学创新工程学院中国澳门999078 布宜诺斯艾利斯工学院电子工程系布宜诺斯艾利斯B1636 巴基斯坦工程技术大学电气工程系讷瓦布沙阿44000

转矩分配函数被广泛应用于抑制开关磁阻电机的转矩脉动。然而,输入相转矩跟踪不足或者输出相产生较大的负转矩这两种情况通常会导致电机的转矩脉动难以得到有效抑制,并降低电机的运行效率。因此,为了能够有效降低电机的转矩脉动并提高... 详细信息

转矩分配函数被广泛应用于抑制开关磁阻电机的转矩脉动。然而,输入相转矩跟踪不足或者输出相产生较大的负转矩这两种情况通常会导致电机的转矩脉动难以得到有效抑制,并降低电机的运行效率。因此,为了能够有效降低电机的转矩脉动并提高电机的效率,提出了一种新型的转矩分配函数控制策略。在提出的转矩分配函数控制策略中,电机的换相区域分为两个区域。在前一区域中,通过降低输入相转矩分配的比例,可以实现输入相实际转矩快速跟踪参考转矩,电机的转矩脉动有效降低。同时由于在输入相电感变化率较低时减少输入相分配的转矩,从而输入相的峰值电流随之降低,电机的转矩电流比提高。在后一区域中,将输出相的电流在转子对齐位置附近处减小到0,以避免产生较大的负转矩。因此,在所提出的方案下,电机的转矩脉动得到有效抑制,电机的效率也得到了提高。为了验证该方法的有效性,在一台12/8三相开关磁阻电机上进行了仿真和实验。结果表明,所提出的转矩分配函数控制策略能有效降低开关磁阻电机转矩脉动,也能有效地提高开关磁阻电机的运行效率。

关键词：开关磁阻电机转矩分配函数负转矩转矩电流比效率