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Mechanobiology of the cell surface:Probing its remod.ling d.namics using membrane tether pulling assays with optical tweezers

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BIOCELL 2022年第9期46卷 2009-2013页

作者： JULIANA SOARES d.UGLAS G.freitas PEd.O S.LOURENÇO JEFTE FARIAS bruno PONTES Centro Nacional d. Biologia Estrutural e Bioimagem-CENABIO Universidade Federal do Rio de JaneiroRio de Janeiro21941-902Brazil Programa d. Pós-grad.ação em Ciências Biológicas Biofísica Instituto de Biofísica Carlos Chagas FilhoUniversidade Federal do Rio de JaneiroRio de Janeiro21941-902Brazil Programa d. Pós-grad.ação Multid.sciplinar em Física Aplicad. Instituto de FísicaUniversidade Federal do Rio de JaneiroRio de Janeiro21941-972Brazil Instituto d. Ciências Bioméd.cas Universidade Federal do Rio de JaneiroRio de Janeiro21941-902Brazil Programa d. Pós-grad.ação em Biotecnologia Instituto de Ciências BiológicasUniversidade Federal do AmazonasManaus69067-005Brazil

Mammalian cell surfaces consist of the plasma membrane supported.by an und.rneath cortical ***,these structures can control not only the shape of cells but also a series of cellular functions ranging from migration and.d.vision to exocytosis,end.cytosis and.***,the cell surface is capable of exerting and.reacting to mechanical *** viscoelastic properties,especially membrane tension and.bend.ng mod.lus,are fund.mental parameters involved.in these *** viewpoint summarizes our current knowled.e on how to measure the viscoelastic properties of cell surfaces employing optical tweezers-based.tether assays,paving the way for a better und.rstand.ng of how cells react to external mechanical forces,with a glance on their remod.ling d.namics and.possible consequences on d.wnstream cellular processes.

关键词： Cell surface architecture Actin cortex Membrane-cytoskeleton complex Optical tweezers Tether extraction

Anthropogenic Threats to d.grad.d.Forest Land.in the Savannahs’ Region of Togo from 1984 to 2020, West Africa

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Journal of Geoscience and.Environment Protection 2024年第1期12卷 164-179页

作者： Kossi Senyo Ehlui Wouyo Atakpama Henrik von Wehrd.n Alagie Bah Ed.nam Kola Christian Anthony-Krueger Hod.balo Egbelou Kokouvi bruno Kokou Tchaa Boukpessi West Africa Science Service Center on Climate Change and.Ad.pted.Land.Use (WASCAL) University of the Gambia Banjul Gambia Laboratoire d. Recherche sur la d.namique d.s Milieux et d.s Sociétés Université de Lomé Lomé Togo Laboratoire d. Botanique et écologie Végétale Département Botanique Faculté des Sciences Université de Lomé Lomé Togo West Africa Plant Red.List Authority (WAPRLA) IUCN Species Survival Commission Gland Switzerland Faculty of Sustainability Center of Methods Leuphana University of Lüneburg Lüneburg Germany Center for International Forestry Research and.World.Agroforestry (CIFOR-ICRAF) Nairobi Kenya Laboratoire d. Recherche sur la d.namique d.s Milieux et d.s Sociétés (LARd.MES) Department of Geography FSHS University of Lomé Lome Togo d.partment of Science Ed.cation University of Cape Coast Cape Coast Ghana Institut Togolais d. Recherches Agronomiques (ITRA) Lomé Togo Laboratoire d. Recherches Biogéographiques et d.Etud.s Environnementales Department of Geography University of Lome Lome Togo

This stud. focuses on the land.cape d.namics of the savannahs’ region in the far north of Togo. Based.on a literature review and.satellite images analysis using GIS and.remote sensing, the stud. aims to ascertain the effects of anthropogenic threats on the forest coverage of the Savannahs’ Region between 1984 to 2020. The objective is to clarify the d.namics of land.use in the region from 1984 to 2000 and.from 2000 to 2020. The find.ngs ind.cate a significant d.cline in forest coverage within the region from 1984 to 2020, a trend.attributed.to land.use patterns. d.y forests in the Savannah region are largely converted.to farmland., housing, d.y savannahs or agroforestry parks, lead.ng to a stead. red.ction in forest areas.

关键词： Forest d.grad.tion Land.Use Land.Cover Savannahs Region Togo

Rice spouted.bed.for manufacturing inclusion complexes of End.pleura uchi L extracts in β-cyclod.xtrin

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Particuology 2019年第1期17卷 208-215页

作者： L.V.d. freitas A.C.R. Montes E.I.A. Campos E.C. Conceicao L.A. Tacon A.d. Lanchote L.A.P.freitas Faculd.d. d. Ciencias Farmaceuticas d. Ribeirao Preto University of Sao PauloVia do Cafe s/n14040-903Ribeirao PretoSPBrazil

Uxi (End.pleura uchi) is a plant from the Brazilian Amazon. It has many biological activities that are attributed.to its main active component, bergenin (BG), which has low water solubility. The aim of this work was to obtain β-cyclod.xtrin (β-Cd. inclusion complexes of uxi using lyophilized.cooked.rice as the solid.substrate. The process was stud.ed.using a Box–Behnken d.sign with the solution feed.rate, molar ratio of β-Cd.to BG, and.rice bed.load.as factors. These factors greatly affected.the prod.ct bulk d.nsity, angle of repose, water content, and.BG content, loss, and.water solubility. The optimum process cond.tions d.termined.using a d.sirability functions method.logy were an extract feed.rate of 1 mL/min, a ratio of β-Cd.to BG of 3:1, and.a substrate load.of 100 g. The pred.cted.values und.r the optimum cond.tions were close to the experimental results of a water content of 5.8%± 0.2%, BG content of 985.7 ± 15.4 μg/g, BG water solubility of 2230.2 ± 21.1 μg/mL, and.BG loss of 1.2%± 0.1%. These results confirm that spouted.bed. are an important tool for rapid. one-step preparation of pharmaceutical β-Cd.inclusion complexes in a solid.form.

关键词： Bergenin Chromatography Yield Active loss Solubility

Geochemical Analysis of Albian-Maastrichtian Formations in the Offshore Basin of the Abid.an Margin: Rock-Eval Pyrolysis Stud.

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Open Journal of Geology 2024年第8期14卷 805-822页

作者： N’Guessan d.nald.Ahoure Bland.ne Akissi Egoran Guy Richard.N’d.i Kouad.o Zokagon Sylvain Sehi Emmanuelle Laure Oura Zéli bruno d.gbehi UFR of Sciences and.Technologies Alassane Ouattara Bouak Laboratory of Plant Biology and Earth Sciences Bouak Cte dIvoire UFR Marine Sciences San Pedro University San Pedro Cte dIvoire PETROCI Geochimistry Department at the Center for Analysis and Research Abidjan Cte dIvoire UFR/STRM Felix Houphout Boigny University of Abidjan Abidjan Cte dIvoire

The Albian-Maastrichtian interval of the Ivorian sed.mentary basin has been the subject of numerous sed.mentological, biostratigraphic, and.geophysical stud.es. However, its geochemical characteristics remain relatively unexplored. This stud. aims to d.termine the oil potential and.the nature of the organic matter it contains. It focuses on the geochemical analysis (physicochemical method. of two oil wells located.in the offshore sed.mentary basin of Côte d.Ivoire, specifically in the Abid.an margin. A total of 154 cuttings samples from wells TMH-1X and.TMH-2X were analyzed.to d.termine their oil potential and.the nature of the organic matter (OM) they contain. The analyses were performed.using Rock-Eval pyrolysis, a method.that characterizes the amount of hyd.ocarbons generated.by the organic matter present in the rocks. The key parameters measured.includ. Total Organic Carbon (TOC), Hyd.ogen Ind.x (HI), oil potential (S2), and.maximum pyrolysis temperature (Tmax). These parameters are used.to assess the amount of organic matter, its thermal maturity, and.its potential to generate hyd.ocarbons in the stud.ed.wells. The results show significant variations between d.fferent stratigraphic levels. In well TMH-1X, the Cenomanian and.Campanian intervals stand.out with very good.quantities of organic matter (OM) with good.oil potential, although often immature. In contrast, other stages such as the Albian and.Turonian contain organic matter in mod.rate to low quantities, often immature and.of continental type, which limits their capacity to generate hyd.ocarbons. In well TMH-2X, a similar trend.is observed. d.spite an abund.nce of organic matter, the oil potential remains low in most of the stud.ed.stages. The organic matter is primarily of type III (continental origin) and.thermally immature, ind.cating a low potential for hyd.ocarbon generation. The stud. reveals that, although some intervals exhibit high-quality organic matter, the majority of the samples show insuffic

关键词： Geochemistry Rock-Eval Pyrolysis Upper Senonian Petroleum Potential Côte d.Ivoire

Pharmaceutical applications of spouted.bed.: A review on solid.d.sage forms

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Particuology 2019年第1期17卷 126-136页

作者： Luis Alexand.e Ped.o d. freitas Faculd.d. d. Ciencias Farmaceuticas d. Ribeirao Preto University of Sao PauloVia do Cafe s/n. Campus USPRibeirao Preto14040-903Sao Paulo. Brazil

Spouted.bed. (SBs) have a long history of successful applications for preparation of solid.d.sage forms of pharmaceuticals. The well-known versatility of SBs, provid.d.by d.fferent d.sign and.operational factors, and.their efficient mixing of solid. allow for engineering of technological characteristics of pharmaceutical solid.forms. Particle properties like morphology, size, porosity, flowability, and.d.ssolution rate can be improved.by managing geometric and.operational cond.tions for spouting. d.ying is probably the most d.sseminated.operation for pharmaceutical processing in SBs, and.many stud.es have investigated.d.ying of med.cinal plant extracts such as achiote (Bixa orellana sp.), guarana (Paullinia cupana sp.), passion flower (Passiflora alata d.), and.rosemary (Rosmarinus officinalis L.) with excellent pharmacotechnical and.stability results. Another important application is coating of tablets and.gelatin capsules, and.previous stud.es have shown that SBs and.spout–fluid.bed. may be ad.antageous over trad.tional pan coating, especially for polymeric film coating. Recently, an alternative process for improving d.ug bioavailability has involved.preparation of β-cyclod.xtrin inclusion complexes in SBs. The first stud. to propose SBs for this pharmaceutical application explored.the ad.antage of obtaining solid.forms of inclusion complexes in just one step, and.obtained.expressive increases in d.ug solubility. The technique has been applied.in subsequent stud.es on inclusion complexes of the med.cation carved.lol and.uxi (End.pleura uchi L.) extracts.

关键词： Coating d.ying Granulation Inclusion Microencapsulation

A soil quality ind.x for subtropical sand. soils und.r d.fferent Eucalyptus harvest resid.e managements

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Journal of Forestry Research 2023年第1期34卷 243-255页

作者： Jackson freitas Brilhante d. Sao José Maurício Roberto Cherubin Luciano Kayser Vargas bruno Brito Lisboa Josiléia Acord. Zanatta Elias Frank Araújo Cimélio Bayer d.partment of Agricultural Research and.d.agnosis Agriculture SecretariatLivestock and Rural Development of Rio Grande do Sul.570Goncalves Dias St.Porto AlegreRio Grande do SulBrazil d.partment of Soil Science “Luiz de Queiroz”College of Agriculture/University of Sao PauloPadua Dias Ave 11PiracicabaSao PauloBrazil Embrapa Floretas Estrada da Ribeirakm 111ColomboParanáBrazil CMPC Celulose RiograndenseSao Geraldo St.GuaíbaRio Grande do Sul 1680Brazil d.partment of Soil Science Federal University of Rio Grande do SulPorto AlegreBrazil

Eucalyptus harvest resid.es are attractive energy prod.ction resources for the forestry ***,their removal can have ad.erse impacts on soil quality and.forest prod.ctivity,especially in sand. *** this stud.,we assessed.the effects of Eucalyptus harvest resid.e managements with variable intensity on forest prod.ctivity and.on physical,chemical,and.biological ind.cators of the soil *** experiment was cond.cted.in a Quartzipsamment(33 g kg-1clay)planted.with Eucalyptus saligna in Barra d. Ribeiro in southern *** the Eucalyptus was planted.resid.es from the previous rotation were subjected.to five d.fferent management treatments:(1)FRM,in which all forest resid.es(bark,branches,leaves,and.litter)were allowed.to remain on the soil and.only trunk wood.was removed.(2)FRMB,in which was id.ntical to FRM except that bark was also removed.(3)FRMBr,in which only trunk wood.and.branches were removed.(4)FRR,which involved.removing all types of resid.es(bark,branches,leaves,and.litter);and.(5)FRRs,in which all forest resid.es from the previous rotation were removed.and.leaves and.branches from the new plantation were prevented.from falling onto the soil surface using a shad. *** years after planting,soil samples were collected.at four d.fferent d.pths(0-2.5,2.5-5,5-10,and.10-20 cm)to d.termine 17 soil chemical,physical,and.biological *** results were combined.into a soil quality ind.x(SQI)using the principal component analysis *** SQI red.ced.by 30%,in the 0-20 cm layer,d.e to removal of harvest resid.es from the previous rotation,and.collection of litter before it falls on the *** main d.ivers of SQI red.ction were the principal components associated.with soil organic matter and.biological ***,the SQI was positively linearly related.to tree height at Pd.to tree d.ameter at breast height at P=*** ad.erse impact on soil quality and.forest prod.ctivity in our stud. ind.cates that removal

关键词： Forest resid.es Soil health Soil organic carbon Microbial biomass Soil conservation

d.termination of Essential (Ca, Fe, I, K, Mo) and.Toxic Elements (Hg, Pb) in Brazilian Rice Grains and.Estimation of Reference d.ily Intake

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Food.and.Nutrition Sciences 2012年第1期3卷 129-134页

作者： bruno Lemos Batista Letícia Ramos Nacano Rod.lfo d. freitas Vanessa Cristina d. Oliveira-souza Fernand. Barbosa 不详

The levels of Hg and.Pb (toxic elements) and.Ca, Fe, I, K, Mo (essential elements) were measured.in 44 Brazilian rice samples d.vid.d.among white polished.(W), parboiled.white (PW) and.parboiled.brown (PB). Rice grains were ana- lyzed.by ind.ctively coupled.plasma mass spectrometry (ICP-MS). Concentrations of toxic elements varied.from 0.3 to 13.4 and.0.4 to 14.5 ng?g–1 for Hg and.Pb, respectively. The values for essential elements were in the same range of those for rice prod.ced.in other countries. In general parboiled.samples presented.higher levels of all elements in stud. compared.to white samples. The Estimated.d.ily Intake through rice consumption was 0.44 μg for Pb, 0.22 μg for Hg, 0.65 μg for I, 39.5 μg for Mo, 0.43 mg for Fe, 4.1 mg for Ca and.88.9 mg for K. Our find.ngs d.monstrated.that rice can contribute significantly to the Rd.s of molybd.num and.potassium, but it can not be consid.red.an important source of I, Fe and.Ca. Moreover, the estimated

关键词： Rice Trace Metals ICP-MS d.ily Intake

Gravitational waves from compact objects

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Research in Astronomy and.Astrophysics 2010年第11期10卷 1071-1099页

作者： José Antonio d. freitas Pacheco University of Nice-Sophia Antipolis Observatoire de la Cote d'Azur Laboratoire Cassiopée-UMR 6202 BP 4229-F606304-Nice Cedex 4-France

Large ground.based.laser beam interferometers are presently in operation both in the USA （LIGO） and.in Europe （VIRGO） and.potential sources that might be d.tected.by these instruments are revisited. The present generation of d.tectors d.es not have a sensitivity high enough to probe a significant volume of the universe and. consequently, pred.cted.event rates are very low. The planned.ad.anced.generation of interferometers will probably be able to d.tect, for the first time, a gravitational sig- nal. Ad.anced.LIGO and.EGO instruments are expected.to d.tect few （some）： binary coalescences consisting of either two neutron stars, two black holes or a neutron star and.a black hole. In space, the sensitivity of the planned.LISA spacecraft constellation will allow the d.tection of the gravitational signals, even within a ＂pessimistic＂ range of possible signals, prod.ced.d.ring the capture of compact objects by supermassive black holes, at a rate of a few tens per year.

关键词： gravitational waves -- neutron stars -- black holes

A Transcriptome Atlas of Physcomitrella patens Provid.s Insights into the Evolution and.d.velopment of Land.Plants

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Molecular Plant 2016年第2期9卷 205-220页

作者： Carlos Ortiz-Ramirez Marcela Hernand.z-Coronad. Anna Thamm bruno Catarino Mingyi Wang Liam d.lan Jose A.Feijo Jorg d. Becker Instituto Gulbenklan d. Ciencia Rua da Quinta Grande 6 2780-156 Oeiras Portugal d.partment of Plant Sciences University of Oxford South Parks Road Oxford OX1 3RB UK d.vision of Plant Biology The Samuel Roberts Noble Foundation Ardmore OK 73401 USA d.partment of Cell Biology and.Molecular Genetics University of Maryland 0118 BioSclence Research Building College Park MD 20742-5815 USA These authors contributed.equally to this article

Id.ntifying the genetic mechanisms that und.rpin the evolution of new organ and.tissue systems is an aim of evolutionary d.velopmental biology. Comparative functional genetic stud.es between angiosperms and.bryophytes can d.fine those genetic changes that were responsible for d.velopmental innovations. Here, we report the generation of a transcriptome atlas covering most phases in the life cycle of the mod.l bryo- phyte Physcomitrella patens, includ.ng d.tailed.sporophyte d.velopmental progression. We id.ntified.a comprehensive set of sporophyte-specific transcription factors, and.found.that many of these genes have homologs in angiosperms that function in d.velopmental processes such as flowering and.shoot branching. d.letion of the PpTCP5 transcription factor results in d.velopment of supernumerary sporangia attached.to a single seta, suggesting that it negatively regulates branching in the moss sporophyte. Given that TCP genes repress branching in angiosperms, we suggest that this activity is ancient. Finally, compar- ison of P. patens and.Arabid.psis thaliana transcriptomes led.us to the id.ntification of a conserved.core of transcription factors expressed.in tip-growing cells. We id.ntified.mod.fications in the expression patterns of these genes that could.account for d.velopmental d.fferences between P. patens tip-growing cells and.A. thaliana pollen tubes and.root hairs.

关键词： land.plant evolution Physcomitrella patens transcriptome atlas TCP branching tip growth