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Effects of Polypropylene Fibers on the Physical and Mechanical Properties of Recycled Aggregate Concrete

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Journal of Wuhan University of Technology(Materials Science) 2019年第6期34卷 1327-1344页

作者： Pierre Matar Gérard-philippe Zéhil Lebanese University Faculty of EngineeringBranch 2RoumiehLebanon Notre Dame University-Louaize Faculty of EngineeringZouk MosbehLebanon

The viability of using polypropylene fibers(PPF) in concrete was largely studied. Yet, few of the existing research studies investigated the effects of PPF on the properties of concrete containing recycled concrete aggregate(RCA). Mixes with different RCA replacement ratios and different PPF content were designed and tested. The test results showed that the addition of PPF did not change significantly the compressive strength and the density of the concrete, but slightly decreased its modulus of elasticity and Poisson’s ratio. The drop in the splitting tensile strength and the flexural strength due to RCA inclusions was to a large extent compensated by the PPF addition. The water absorption decreased and the percent voids increased with increased PPF addition. Correlations between the RCA content, the PPF content and the properties of concrete were studied. Useful regression models were proposed to predict the properties of concrete in relevant ranges of RCA and PPF content.

关键词： concrete recycled aggregate fiber reinforcement physical properties mechanical properties

Proapoptotic RECS1: a requisite gateway to lysosomal dysfunction and death

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Neural Regeneration Research 2022年第12期17卷 2695-2696页

作者： philippe Pihán Mateus Milani Claudio Hetz Biomedical Neuroscience Institute Faculty of MedicineUniversity of ChileSantiagoChile Center for Geroscience Brain Health and Metabolism(GERO)SantiagoChile Program of Cellular and Molecular Biology Institute of Biomedical SciencesUniversity of ChileSantiagoChile Buck Institute for Research on Aging NovatoCAUSA

For a long time since their discovery by Christian de Duve in the 1950s,lysosomes have been referred to almost exclusively as passive garbage bags;the endpoint in the degradation of intra-and extracellular *** catabolic function of lysosomes is accomplished by an array of more than 60 acid hydrolases,which together break down a wide variety of biological macromolecules,including proteins,lipids,carbohydrates,and nucleic acids,for reutilization in the metabolic processes of the *** their optimal function,these enzymes require an acidic intraluminal pH of~4.5,which is maintained by the joint action of a proton pump,the vacuolar H+-ATPase,and several ion channels embedded in the lysosomal limiting membrane.

关键词： maintained limiting function

Success of three soil restoration techniques on seedling survival and growth of three plant species in the Sahel of Burkina Faso(West Africa)

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Journal of Forestry Research 2016年第2期27卷 313-320页

作者： philippe Bayen Anne Mette Lykke Adjima Thiombiano Laboratory of Plant Biology and Ecology University of Ouagadougou Department of Bioscience Aarhus University

In the Sahel of Africa, where 90 % of the population depends on natural resources for their liveli- hood, a large part of the soils are structurally unstable, prone to crusting and hard setting, and have low water holding capacity, which hamper vegetation establishment. The effect of soil restoration techniques on survival and growth of seedlings of Acacia nilotica, Acacia tortilis and Jatropha curcas was tested in completely barren, degraded land in a Sahelian ecosystem in Burkina Faso. A total of 522 seedlings （174 plants of each plant species） were planted in a randomized complete block design with three replicates combining three soil preparation techniques： half-moon, zai＂ and standard plantation. Survival and growth rates evaluated over 20 months were significantly higher using the half-moon technique compared with the other two techniques. Survival rates of plant species planted using half-moon technique were 62.5, 28.57 and 10.71% for A. nilotica, A. tortilis and J. curcas respec- tively, but in za＇i and standard planting, seedling survival was zero. The low survival rate of J. curcas using the half-moon technique may indicate that J. curcas is unsuit- able for barren and degraded land, whereas A. nilotica and A. tortilis appear to be promising tree species for rehabil- itation of degraded land.

关键词： Afforestation Bare soil Soil rehabilitation Species selection Water conservation

When parasitoids deal with the spatial distribution of their hosts: consequences for both partners

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Insect Science 2019年第5期26卷 923-931页

作者： philippe Louapre Cecile Le Lann Thierry Hance Earth and Life Institue Universite Catholique de LouvainLouvain-la-NeuveBelgium CNRS Biogeosciences UMR 6282Universite Bourgogne Franche-ComteDijonFrance UMR CNRS 6553 Ecobio University of Rennes 1Rennes CedexFrance

Insect parasitoids developing inside hosts face a true challenge: hosts are scattered in the field and their localization and selection require the use of complex and sometime confusing information. It was assumed for a long time that small-brained organisms like parasitoids have evolved simple and efficient behavioral mechanisms, leading them to be adapted to a given ecological situation, for example, the spatial distribution o f hosts in the habitat. However, hosts are not static and their distribution may also vary through generations and within the life of parasitoid individuals. We investigated if and how parasitoids deal with such a spatial com plexity in a m esocosm experiment. We used the Aphidius rhopalosiphi/Sitobion avenae parasitoid/host system to investigate if parasitoid females experiencing different host aggregation levels exhibit different foraging behaviors independently of the number of hosts in the environment. We showed that A. rhopalosiphi females exploited hosts more intensively both within and among patches at higher host aggregation levels. We discussed the adaptiveness of such behaviors in the light of evolution and biological control.

关键词： Aphidius rhopalosiphi foraging behavior parasitoid sequential adjustment Sitobion avenae spatial distribution

Egg clutch patterning in Lestes virens （Odonata, Lestidae） with evolutionary emphasis on endophytic oviposition in lestid dragonflies

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Insect Science 2016年第6期23卷 893-902页

作者： Natalia A. Matushkina Denis Buy philippe Lambret Department of Zoology Institute of Biology Taras Shevchenko National University of Kyiv Kyiv 01033 Ukraine Institute of Food Biotechnology and Genomics NAS of Ukraine Kyiv 04123 Ukraine Tour du Valat Research Centre Le Sambuc Aries 13200 France

Egg deposition within plants is one of the most widely distributed and ancient behaviors in Odonata. The resulting clutch consists of eggs placed in peculiar pattern that can be a characteristic for certain groups of Odonata. Despite their importance for paleontological and evolutionary research, data on egg-clutch positioning are missing or insufficient for most species. Here, patterning of egg clutches in Lestes virens was measured and described in detail for the first time. The female usually produces a linear row of single eggs directed at an angle rightward or leftward to the longitudinal axis of plant substrate. Less often eggs are arranged in egg-sets consisting of up to 4 eggs. Apparently, the female insect follows the rigid behavior stereotypes during oviposition and is unable to easily switch to the alternate stereotypical behavior of single egg deposition or production of multiegg sets. Based on a literature review and original data, egg clutch patterning of European Lestidae is overlaid on preexisting phylogenies. The resulting evolutionary scenario of egg-clutch patterning can be considered in the framework of egg-laying behavior in Lestidae.

关键词： behavior egg deposition endophytic oviposition evolution paleontology phylogeny

Beneficial effect of whole-grain wheat on liver fat:a role for the gut microbiota?

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Hepatobiliary Surgery and Nutrition 2021年第5期10卷 708-710页

作者： philippe Gérard Micalis Institute UniversitéParis-SaclayINRAEAgroParisTechJouy-en-JosasFrance

In meta-analyses of prospective studies,high whole grain(WG)intake has been acknowledged for its potential role in lowering risk of type 2 diabetes,cancer,cardiovascular disease and all cause mortality(1,2).Unlike Refined wheat(RW)flours from which the bran and germ of the wheat kernel have been removed,whole-grain wheat(WGW)products retain these elements and are rich sources not only of dietary fiber,but also of betaine,choline,important minerals and vitamins,components with antioxidant properties,and other phytochemicals(3).They are thus considered nutritionally superior but previous WG interventions in human subjects have reported conflicting results in improvements in health parameters.

关键词： grain wheat removed

Gemcitabine in elderly patients with advanced pancreatic cancer

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World Journal of Gastroenterology 2011年第30期17卷 3497-3502页

作者： Olivia Hentic Vinciane Rebours philippe Lévy philippe Ruszniewski Pascal Hammel Magaly Zappa Chantal Dreyer Eric Raymond Ple des maladies de l'Appareil Digestif Service de PancréatologieHpital Beaujon100 boulevard du général Leclerc92110 ClichyFrance Ple des maladies de l’Appareil Digestif Service de PancréatologieHpital Beaujon100 boulevard du général Leclerc92110 ClichyFrance Service de Radiologie Hpital Beaujon100 boulevard du général Leclerc92110 ClichyFrance Service de Cancérologie Hpital Beaujon100 boulevard du général Leclerc92110 ClichyFrance

AIM： TO assess feasibility, tolerability and efficacy of gemcitabine-based chemotherapy in patients ≥ 75 years old with advanced pancreatic cancer. METHODS： All consecutive patients ≥ 75 years old with advanced pancreatic adenocarcinoma were included in this retrospective study. Necessary criteria to receive chemotherapy were： performance status 0-2, adequate biological parameters and no serious comorbidities. Other patients received best supportive care （BSC）. RESULTS： Thirty-eight patients （53% women, median age 78 years, range 75-84） with pancreatic cancer （metastatic： n = 20, locally advanced： n = 18） were studied. Among them, 30 （79%） were able to receive chemotherapy [median number： 9 infusions （1-45）]. Six patients （23%） had at least one episode of grade 3 neutropenia and one patient developed a grade 3 hemolytic-uremic syndrome. No toxic death occurred. Three patients （11%） had a partial tumor response, 13 （46%） had a stable disease and 12 （43%） had a tumor progression. Median survival was 9.1 mo （metastatic： 6.9 too, locally advanced： 11.4 too）. CONCLUSION： Tolerance and efficacy of gemcitabinebased chemotherapy is acceptable in elderly patients in good condition, with similar results to younger patients.

关键词： Elderly Pancreas Cancer Gemcitabine

Role of iron in hepatic fibrosis: One piece in the puzzle

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World Journal of Gastroenterology 2007年第35期13卷 4746-4754页

作者： Marie A philippe Richard G Ruddell Grant A Ramm Hepatic Fibrosis Group The Queensland Institute of Medical ResearchPO Royal Brisbane and Women's HospitalBrisbane 4029Australia

Iron is an essential element involved in various biological pathways. When present in excess within the cell, iron can be toxic due to its ability to catalyse the formation of damaging radicals, which promote cellular injury and cell death. Within the liver, iron related oxidative stress can lead to fibrosis and ultimately to cirrhosis. Here we review the role of excessive iron in the pathologies associated with various chronic diseases of the liver. We also describe the molecular mechanism by which iron contributes to the development of hepatic fibrosis.

关键词： Iron Fibrosis Oxidative stress Hepatic stellate cell Haemochromatosis Hepatitis C Non-alcoholic fatty liver disease Alcoholic liver disease

Prediction on temperature dependent elastic constants of “soft” metal Al by AIMD and QHA

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Journal of Materials Science & Technology 2020年第10期42卷 92-97页

作者： Haijun Zhang Chenhui Li philippe Djemia Rui Yang Qingmiao Hua Institute of Metal Research Chinese Academy of SciencesWenhua Road 72Shenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaJinzhai Road 96Hefei230026China LSPM-CNRS3407 Universite Paris 13Sorbonne Paris CiteVilletaneuse93430France

First-principles methods based on density functional theory(DFT)are nowadays routinely applied to calculate the elastic constants of materials at temperature of 0 ***,the first-principles calculations of elastic constants at finite temperature are not *** the present work,the feasibility of the ab initio molecular dynamic(AIMD)method in calculations of the temperature dependent elastic constants of relatively"soft"metals,taking face centered cubic(FCC)aluminum(Al)as example,is *** AIMD calculations are performed with carefully selected strain tensors and strain *** parallel with the AIMD calculations,first-principles calculations with the quasiharmonic approximation(QHA)are performed as *** show that all three independent elastic constant components(C11,C12 and C44)of Al from both the AIMD and QHA calculations decrease with increasing temperature T,in good agreement with those from experimental *** work allows us to quantify the individual contributions of the volume expansion,lattice vibration(excluding those contributed to the volume expansion),and electronic temperature effects to the temperature induced variation of the elastic *** Al with stable FCC crystal structure,the volume expansion effect contributes the major part(about 75%~80%)in the temperature induced variation of the elastic *** contribution of the lattice vibration is minor(about 20%~25%)while the electronic temperature effect is *** the elastic constants soften with increasing temperature,FCC Al satisfies the Born elastic stability criteria with temperature up to the experimental melting point.

关键词： Elastic constant First-principle Molecular dynamics Vibration Aluminum