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degradable magnesium-hydroxyapatite interpenetrating phase composites processed by current assisted metal infiltration in additive-manufactured porous preforms

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Journal of magnesium and Alloys 2022年第12期10卷 3641-3656页

作者： mariano Casas-Luna Edgar B.montufar Norbert Hort Sebastian Díaz-de-la-torre JoséClaudio méndez-García Lucie Vištejnová Adam Brínek AlešDanhel Karel Dvorak Jozef Kaiser ladislav Celko Central European Institute of Technology Brno University of TechnologyPurkynova 123Brno 61200Czech Republic Institute of metallic Biomaterials Helmholtz-Zentrum HereonMax-Planck-Straße 1Geesthacht 21502Germany Institute of Product and Process Innovation Leuphana University LüneburgUniversitätsallee 1Lüneburg 21335Germany Centro de Investigación e Innovación Tecnológica Instituto Politécnico NacionalCerrada de Cecati s/nMexico City 02250Mexico Biomedical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 1655/76Plzen 32300Czech Republic Institute of Biophysics of the Czech Academy of Sciences Královopolská135Brno 61265Czech Republic Faculty of Civil Engineering Brno University of TechnologyPurkynova 139Brno 61200Czech Republic

This work explores ceramic additive manufacturing in combination with liquid metal infiltration for the production of degradable interpenetrating phase magnesium/hydroxyapatite(mg/HA) composites. material extrusion additive manufacturing was used to produce stoichiometric,and calcium deficient HA preforms with a well-controlled open pore network, allowing the customization of the topological relationship of the composite. Pure mg and two different mg alloys were used to infiltrate the preforms by means of an advanced liquid infiltration method inspired by spark plasma sintering, using a novel die design to avoid the structural collapse of the preform. Complete infiltration was achieved in 8 min, including the time for the mg melting. The short processing time enabled to restrict the decomposition of HA due to the reducing capacity of liquid mg. The pure mg-base composites showed compressive yield strength above pure mg in cast state. mg alloy-based composites did not show higher strength than the bare alloys due to grain coarsening, but showed similar mechanical properties than other mg/HA composites that have significantly higher fraction of metallic phase. The composites showed faster degradation rate under simulated body conditions than the bare metallic component due to the formation of galvanic pairs at microstructural level. mg dissolved preferentially over HA leaving behind a scaffold after a prolonged degradation period. In turn, the fast production of soluble degradation products caused cell metabolic changes after 24 h of culture with not-diluted material extracts. The topological optimization and reduction of the degradation rate are the topics for future research.

关键词： Interpenetrating phase composite Biodegradable metal Topological relationship Direct ink writing metal infiltration Computed aided design

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Novel insights into D-Pinitol based therapies:a link between tau hyperphosphorylation and insulin resistance

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Neural Regeneration Research 2024年第2期19卷 289-295页

作者： Dina medina-Vera Antonio Jesús López-Gambero Juan Antonio Navarro Carlos Sanjuan Elena Baixeras Juan decara Fernando Rodríguez de Fonseca Instituto de Investigación Biomédica de málaga y Plataforma en Nanomedicina-IBImA Plataforma BIONAND UGC Salud MentalMálagaSpain Facultad de Ciencias Universidad de MálagaMálagaSpain CIBER Enfermedades Cardiovasculares(CIBERCV) Hospital Universitario Virgen de la VictoriaUGC del CorazónMálagaSpain University of Bordeaux INSERMNeurocentre MagendieBordeauxFrance Euronutra S.L.Calle Johannes Kepler MálagaSpain departamento de Bioquímica y Biología molecular Facultad de MedicinaUniversidad de MálagaMálagaSpain

Alzheimer’s disease is a neurodegenerative disorder characterized by the amyloid accumulation in the brains of patients with Alzheimer’s *** pathogenesis of Alzheimer’s disease is mainly mediated by the phosphorylation and aggregation of tau *** the multiple causes of tau hyperphosphorylation,brain insulin resistance has generated much attention,and inositols as insulin sensitizers,are currently considered candidates for drug *** present narrative review revises the interactions between these three elements:Alzheimer’s disease-tau-inositols,which can eventually identify targets for new disease modifiers capable of bringing hope to the millions of people affected by this devastating disease.

关键词： Alzheimer’s disease cyclin-dependent kinase 5 diabetes D-Pinitol inositols insulin resistance kinases phosphorylation PI3K/Akt tau

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Adult neurogenesis:a real hope or a delusion?

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Neural Regeneration Research 2024年第1期19卷 6-15页

作者： Ghulam Hussain Rabia Akram Haseeb Anwar Faiqa Sajid Tehreem Iman Hyung Soo Han Chand Raza Jose-Luis Gonzalez de Aguilar Neurochemicalbiology and Genetics laboratory(NGL) Department of PhysiologyFaculty of Life SciencesGovernment College UniversityFaisalabadPunjabPakistan department of Physiology School of MedicineClinical Omics InstituteKyungpook National UniversityDaeguKorea department of Zoology Faculty of Chemistry and Life SciencesGovernment College UniversityLahorePakistan INSERm U1118Mécanismes Centraux et Péripheriques de la NeurodégénérescenceStrasbourgFranceUniversitéde StrasbourgStrasbourgFrance

Adult neurogenesis,the process of creating new neurons,involves the coordinated division,migration,and differentiation of neural stem *** process is restricted to neurogenic niches located in two distinct areas of the brain:the subgranular zone of the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricle,where new neurons are generated and then migrate to the olfactory *** has been thought to occur only during the embryonic and early postnatal stages and to decline with age due to a continuous depletion of neural stem ***,recent years have seen tremendous progress in our understanding of adult brain neurogenesis,bridging the knowledge gap between embryonic and adult ***,we discuss the current status of adult brain neurogenesis in light of what we know about neural stem *** this notion,we talk about the importance of intra cellular signaling molecules in mobilizing endogenous neural stem cell prolife *** on the current understanding,we can declare that these molecules play a role in targeting neurogenesis in the mature ***,to achieve this goal,we need to avoid the undesired proliferation of neural stem cells by controlling the necessary checkpoints,which can lead to tumorigenesis and prove to be a curse instead of a blessing or hope.

关键词： adult neurogenesis aging brain-derived neurotrophic factor dentate gyrus hippocampus neural stem cells neurotrophic factors Notch oxidative stress stem cells subgranular zone

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Direct microwave leaching conditions of rare earth elements in fluorescent wastes

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.Bilen B.Birol m.N.Saridede S.S.Kaplan m.S.Sonmez department of metallurgical and materials Engineering Yildiz Technical UniversityIstanbulTurkey department of Chemical Engineering and materials Science Stevens Institute of TechnologyNew JereyUSA department of metallurgical and materials Engineering Istanbul Technical UniversityIstanbulTurkey

The luminescent phosphor powder in the fluorescent lamp constitutes 2%of the lamp’s *** can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth *** the present study,microwave leaching process was conducted to dissolve rare earth elements yttrium(Y),europium(Eu),and remaining rare earth elements(REEs)present in the phosphor powder of the fluorescent *** the yields were *** the microwave leaching process,the effects of the temperature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HNO_(3)),sulphuric acid(H_(2)SO_(4))),acid concentration(0.5-6 mol/L),solid to liquid ratio(0.1:10-0.5:10)and reaction time(5-90 min)parameters on leaching efficiencies of varying rare earth elements and calcium were *** highest yield was obtained in the direct microwave leaching of fluorescent waste with the experimental conditions of 6 mol/L HCl,160℃,0.1:10 solid-to-liquid ratio(S:L),and 90 *** energy calculations were made,and kinetic models of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum(la),cerium(Ce),and terbium(Tb)were examined to be chemical reaction ***,calcium(Ca)and gadolinium(Gd)seem coherent with the mixed ***,mathematical models of all experimental studies are created with the response surface Box-Behnken method and the correlation coefficients of all the models are over 90%.

关键词： Rare earth elements(REEs) Direct microwave leaching Fluorescent waste Kinetic models Response surface method

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放电等离子超快速烧结SiC-Al_2O_3纳米复相陶瓷

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无机材料学报 1999年第1期14卷 55-60页

作者：高濂王宏志洪金生宫本大树 DIAZ de la torre SEBASTIAN 中国科学院上海硅酸盐研究所高性能陶瓷和超微结构国家重点实验室上海200050 日本大阪府立产业技术综合研究所

本文介绍用非均相沉淀法制备的纳米SiC－Al2O3复合粉体经放电等离子超快速烧结得到晶内型的纳米复相陶瓷，超快速烧结的升温速率为600℃／min，在烧结温度不保温，迅即在3min内冷却至600℃以下．与热压烧结相比，可降低烧结温度200℃以... 详细信息

本文介绍用非均相沉淀法制备的纳米SiC－Al2O3复合粉体经放电等离子超快速烧结得到晶内型的纳米复相陶瓷，超快速烧结的升温速率为600℃／min，在烧结温度不保温，迅即在3min内冷却至600℃以下．与热压烧结相比，可降低烧结温度200℃以上．力学性能研究结果表明，在1450℃超快速烧结得到的纳米复相陶瓷的抗弯强度高达1000mPa，维氏硬度为19GPa，断裂韧性也比Al2O3有所提高．TEm像显示纳米SiC颗粒大多分布在Al2O3母体晶粒内，而断裂表面的SEm像表明，穿晶断裂是其主要的断裂模式，这是所制备的纳米复相陶瓷力学性能大幅提高的主要原因．

关键词：碳化硅施电等离子烧结纳米粉体复合陶瓷

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Fabrication of Gypsum Panels with Low-Cost Alternative materials

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Journal of Geological Resource and Engineering 2018年第1期6卷 19-24页

作者： Jose de la torre Luis Tapia Ernesto de la Torte Sebastian Gamez modular Q Quito 170102 Ecuador department of Extractive metallurgy Escuela Politdenica Nacional Ladr6n de Guevara E11-253 Quito Ecuador

During decades, gypsum has been employed as construction material for its versatility and particle size. In the present work, the possibility of developing gypsum panels with the incorporation of pumice and polypropylene as alternative materials has been investigated. Pumice as well as polypropylene allows obtaining lighter panels than those on the market and with a lower production cost. Each one of these materials was characterized separately. In the case of gypsum and pumice, their granulometry, pH and humidity were determined, whereas polypropylene was characterized by a traction-deformation essay. Then, panels composition （gypsum and pumice concentration）, particle size, water temperature and the way polypropylene was added, was assessed. Panels with a 70% of gypsum, with a particle size of 198 btm and with polypropylene added in a laminar fashion, presented a compressive strength of 350 kPa, which accords to the norm ASTm 1396 and with market requirements. Finally, it was proposed a block diagram of the process for the fabrication of 100 kg/day of formulated panels.

关键词： Panels gypsum pumice polypropylene.

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Recovery of Gold, Silver, Copper and Niobium from Printed Circuit Boards Using Leaching Column Technique

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Journal of Earth Science and Engineering 2012年第10期2卷 590-595页

作者： Ricardo montero Alicia Guevara Ernesto de la torre Faculty of Chemical Engineering and Agro-industry Extractive Metallurgy Department National Polytechnic University Quito17012759 Ecuador

Nowadays, over 300 tons of Au are used in electronic equipment each year with other precious and strategic metals such as Ag, Pt, Pd, Cu, Nb, Ta, etc.. After the use-phase, the electronic devices become electronic waste （e-waste）; consequently it is important to consider e-waste as a secondary supply for the recovery of these metals. This paper presents the recovery ofAu, Ag, Cu and Nb from PCBs （printed circuit boards） of discarded computers using leaching column technique. The PCBs were crushed with a hammer mill until reaching a particle size between 3.33 mm to 0.43 mm, Then, it was leached with a sodium cyanide solution in a glass column using the following conditions： sodium cyanide concentration 4 g/L, flux 20 L/d kg PCBs day, pH between 10.5 to 11 and leaching time 15 days. Every day, after leaching, the pregnant solutions passed through a column with activated carbon to complete the closed loop system. The following recoveries were obtained： Au 46.6%, Ag 51.3%, Nb 47.2% and Cu 62.3%. A preliminary technical-economic study shows the feasibility to create a small-scale PCBs recycling plant. The initial investment is on the order of USS155,639, considering the recovered metals from the loaded carbon. The internal rate of return for a 10 years period IRR （internal rate of return） and NPV （net present value） estimated are 27% and US$105,926 respectively.

关键词： Printed circuit boards recovery precious metals niobium.

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Prenatal multiple micronutrient-fortified balanced energy-protein supplementation and newborn telomere length and mitochondrial DNA content: a randomized controlled efficacy trial in rural Burkina Faso

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Food Science and Human Wellness 2024年

作者： Giles T.Hanley-Cook Yuri Bastos-moreira Dries S.martens Trenton Dailey-Chwalibóg laeticia Celine Toe Brenda de Kok Lionel Ouédraogo Alemayehu Argaw Kokeb Tesfamariam Patrick Kolsteren Lieven Huybregts Tim S.Nawrot Sarah de Saeger marthe de Boevre Carl lachat department of Food Technology， Safety and Health， Faculty of Bioscience Engineering， Ghent University Center of Excellence in mycotoxicology and Public Health， mYTOXSOUTH~(?) Coordination Unit， Faculty of Pharmaceutical Sciences， Ghent University Centre for Environmental Sciences， Hasselt University Unité Nutrition et maladies métaboliques， Institut de Recherche en Sciences de la Santé (IRSS) Centre muraz Center of Excellence in mycotoxicology and Public Health， mYTOXSOUTH? Coordination Unit， Faculty of Pharmaceutical Sciences， Ghent University Nutrition， Diets， and Health Unit， department of Food and Nutrition Policy， International Food Policy Research Institute (IFPRI) department of Public Health & Primary Care， University of Leuven department of Biotechnology and Food Technology， Faculty of Science， University of Johannesburg， Doornfontein Campus

Background: Evidence regarding the effectiveness of prenatal nutritional supplements has mainly considered anthropometric pregnancy outcomes. The effect on markers of health and disease， such as offspring telomere length (TL) and mitochondrial DNA content (mtDNAc) is unknown. Objectives: We assessed the efficacy of maternal multiple micronutrient (mmN)-fortified balanced-energy protein (BEP) and iron-folic acid (IFA) supplementation on newborn TL as a secondary outcome and mtDNAc as a non-declared outcome. design: We conducted a randomized controlled trial in rural Burkina Faso， among pregnant females (15-40 years old) enrolled at mothers received either mmN-fortified BEP and IFA (intervention) or IFA only (control) throughout pregnancy. Whole arterial blood samples were collected from the umbilical cord of 104 control and 90 intervention group infants， respectively. Average relative TL and mtDNAc were measured using quantitative polymerase chain reaction. Linear regression models were fitted to assess TL and mtDNAc differences across trial arms. Results: We found that a combined daily mmN-fortified BEP supplement and IFA tablet did not affect newborn TL [β = -0.010 (95% CI: -0.057， 0.036); P = 0.662] or mtDNAc [β = 0.065 (95% CI: -0.203， 0.073); P = 0.354]， as compared to an IFA tablet alone. These findings were confirmed (P > 0.05) by adjusting the regression models for potential prognostic factors of study outcomes at enrollment. Exploratory analyses indicated higher， but non-significantly different mtDNAc among children born either small-for-gestational age， low birthweight， or preterm. Conclusions: Newborns from mothers who received daily nutritional supplements across gestation did not have different relative TL or mtDNAc.

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中国早期人类分布的环境制约因素探讨

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第四纪研究 2021年第5期41卷 1342-1356页

作者：丁馨杜雨薇徐欣裴树文 de la torre Ignacio 高星英国伦敦大学学院考古研究所英国伦敦WC1H 0PY 中国科学院脊椎动物演化与人类起源重点实验室中国科学院古脊椎动物与古人类研究所机构北京100044 中国科学院机构生物演化与环境卓越创新中心北京100044 西班牙国家研究委员会历史研究所西班牙马德里28037 中国科学院大学机构北京100049

在环境因素起制约作用的背景下,随着中国古人类演化与生存能力的进步,其数量和空间分布在不同时间段呈现出不同的特征。为了更好地了解中国早期人类的时空分布特征,本研究以中国境内已发表的2110处旧石器遗址的坐标和年代信息为基础,采... 详细信息

在环境因素起制约作用的背景下,随着中国古人类演化与生存能力的进步,其数量和空间分布在不同时间段呈现出不同的特征。为了更好地了解中国早期人类的时空分布特征,本研究以中国境内已发表的2110处旧石器遗址的坐标和年代信息为基础,采用统计学和空间分析的方法,对遗址的时间分布进行以蒙特卡洛模拟为基础的时间不定性模拟,对遗址的空间分布进行核密度估计和聚类分析;同时,利用环境空间数据集中的海拔、水源、气温和降水信息,对不同时期内各个遗址所在地的环境条件进行统计分析。研究结果表明,在旧石器时代,随着时间的发展,中国境内的遗址数量不断增多,分布范围也逐渐从中部、南部和东部地区向条件较恶劣的北部和西部扩张。其中,600 ka和57 ka为这一变化的两个关键时间点,600 ka之前遗址数量较少,分布也较为局限;在600 ka至57 ka之间,遗址数量缓慢增加,分布范围也在季风区内逐渐扩大;57 ka之后,遗址数量迅速增长,分布遍布中国境内的大部分地区。本文所梳理的中国境内旧石器遗址整体时空分布特征,为进一步解读中国早期人类的环境适应能力,特别是古人类的体质演化和技术进步的环境驱动机制提供参考。

关键词：古人类分布环境因素空间分析统计分析中国

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Evidence based medicine and surgical approaches for colon cancer: Evidences, benefits and limitations of the laparoscopic vs open resection

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World Journal of Gastroenterology 2014年第13期20卷 3680-3692页

作者： laura Lorenzon marco la torre Vincenzo Ziparo Francesco montebelli Paolo mercantini Genoveffa Balducci mario Ferri department of Translational medicine Sant’Andrea HospitalFaculty of Medicine and Psychology University of Rome "La Sapienza"00189 RomeItaly

AIm: To report a meta-analysis of the studies that compared the laparoscopic with the open approach for colon cancer resection.

关键词： laparoscopy Colon resection Colon cancer meta-analysis Evidence-based medicine

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