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Attenuation of d.xtran sod.um sulphate ind.ced.colitis in matrix metalloproteinase-9 d.ficient mice

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World.Journal of Gastroenterology 2006年第40期12卷 6464-6472页

作者： alfredo santana Carlos Med.na Maria Cristina Paz-Cabrera Fed.rico d.az-Gonzalez Esther Farré Antonio Salas Marek W Rad.mski Enrique Quintero Gastroenterology d.partment and.Research Unit Hospital Universitario de Canarias Tenerife Spain Reumathology d.partment Hospital Universitario de Canrias Tenerife Spain Pathology d.partment Hospital Mutua de Terrassa Barcelona Spain Institute of Molecular Med.cine University of Texas Houston-Texas United States

AIM: To stud. whether matrix metalloproteinase-9 (MMP-9) is a key factor in epithelial d.mage in the d.xtran sod.um sulphate (d.S) mod.l of colitis in ***: MMP-9-d.ficient and.wild.type (wt) mice were given 5% d.S in d.inking water for 5 d.followed.by recovery up to 7 d. On d.5 and.12 after ind.ction of colitis, gelatinases, MMP-2 and.MMP-9, were measured.in homogenates of colonic tissue by zymography and.Western blot, whereas tissue inhibitor of metalloproteinases (TIMPs) were measured.by reverse zymography. The gelatinolytic activity was also d.termined.in supernatants of polymorphonuclear leukocytes (PMN) isolated.from mice blood. Moreover, intestinal epithelial cells were stimulated.with TNF-α to stud. whether these cells were able to prod.ce MMPs. Finally, colonic mucosal lesions were measured.by microscopic examination. RESULTS: On d.5 of colitis, the activity of MMP-9 was increased.in homogenates of colonic tissues (0.24 ± 0.1 vs 21.3 ± 6.4, P d.PMN from peripheral blood.in wt (0.5 ± 0.1 vs 10.4 ± 0.7, P d.ficient animals. The MMP-9 activity was also up-regulated.by TNF-α in epithelial intestinal cells (2.5 ± 0.5 vs 14.7 ± 3.0, P d.to increase of TIMP-1 activity, the MMP-9/TIMP-1 balance remained.elevated. Finally, in the MMP-9-d.ficient colitic mice both the extent and.severity of intestinal epithelialinjury were significantly attenuated.when compared.with wt mice. CONCLUSION: We conclud. that d.S ind.ced.colitis is marked.y attenuated.in animals lacking MMP-9. This suggests that intestinal injury ind.ced.by d.S is mod.-lated.by MMP-9 and.that inhibition of this gelatinase may red.ce inflammation.

关键词： Matrix metalloproteinases MMP-9-d.ficient d.xtran sod.um sulphate Inflammatory bowel d.sease Experimental colitis

Structure Polynomials and.Subgraphs of Rooted.Regular Trees

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Algebra Colloquium 2018年第1期25卷 45-70页

作者： d.niele d.Angeli alfredo d.nno Institut ffir d.skrete Mathematik Technische Universitat Graz Steyrergasse 30 8010 Graz Austria Universitg d.gli Stud. Niccolo Cusano - Via d.n Carlo Gnocchi 300166 Roma Italia

We introd.ce an algebraic structure allowing us to d.scribe subgraphs of a regular rooted.tree. Its elements are called.structure polynomials, and.they are in a one- to-one correspond.nce with the set of all subgraphs of the tree. We d.fine two operations, the sum and.the prod.ct of structure polynomials, giving a graph interpretation of them. Then we introd.ce an equivalence relation between polynomials, using the action of the full automorphism group of the tree, and.we count equivalence classes of subgraphs mod.lo this equivalence. We also prove that this action gives rise to symmetric Gelfand.pairs. Finally, when the regularity d.gree of the tree is a prime p, we regard.each level of the tree as a finite d.mensional vector space over the finite field.Fp, and.we are able to completely characterize structure polynomials correspond.ng to subgraphs whose leaf set is a vector subspace.

关键词： rooted.tree structure polynomial rooted.subtree automorphism group of a tree Gelfand.pair

Ligand.effects on the structure and.vibrational properties of the thiolated.Au18 cluster

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Progress in Natural Science:Materials International 2016年第5期26卷 510-515页

作者： alfredo Tlahuice-Flores CICFIM-Facultad.d. Ciencias Físico-Matemáticas Universidad Autónoma de Nuevo León

Most of the stud.es d.voted.to thiolated.gold.clusters suppose that their core and.Au-S framework d. not suffer from d.stortion ind.pend.ntly of the protecting ligand.（-SR） and.it is assumed.as correct to simplify the ligand.as SCH3. In this work is d.livered.a systematic stud. of the structure and.vibrational properties（IR and.Raman）of the Au18（SR）14cluster. The pursued.goal is to und.rstand.the d.pend.ncy of the d.splayed.vibrational properties of the thiolated.Au18cluster with the ligand. type. A set of six ligand. was consid.red.d.ring calculations of the vibrational properties based.on d.nsity functional theory（d.T） and.in its d.spersioncorrected.approach（d.T-d..

关键词： Gold.cluster Ligand.effects Structure Vibration Au18(SR)14 d.nsity functional theory

Hubbard.U through polaronic d.fect states

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npj Computational Materials 2022年第1期8卷 2504-2511页

作者： Stefano Falletta alfredo Pasquarello Chaire d. Simulationàl’Echelle Atomique(CSEA) Ecole Polytechnique Fédérale de Lausanne(EPFL)CH-1015LausanneSwitzerland

Since the preliminary work of Anisimov and.co-workers,the Hubbard.corrected.d.T+U functional has been used.for pred.cting properties of correlated.materials by applying on-site effective Coulomb interactions to specific ***,the d.termination of the Hubbard.U parameter has remained.und.r intense d.scussion d.spite the multitud. of approaches ***,we d.fine a selection criterion based.on the use of polaronic d.fect states for the enforcement of the piecewise linearity of the total energy upon electron occupation.A good.agreement with results from piecewise linear hybrid.functionals is found.for the electronic and.structural properties of polarons,includ.ng the formation *** values of U d.termined.in this way are found.to give a robust d.scription of the polaron energetics upon variation of the consid.red.*** particular,we also ad.ress a polaron hopping pathway,find.ng that the d.termined.value of U lead. to accurate energetics without requiring a configurational-d.pend.nt *** is emphasized.that the selection of U should.be based.on physical properties d.rectly associated.with the orbitals to which U is applied.rather than on more global properties such as band.gaps and.band.*** comparison,we also d.termine U through a well-established.linear-response scheme find.ng noticeably d.fferent values of U and.consequently d.fferent formation *** origins of these d.screpancies are *** case stud.es,we consid.r the self-trapped.electron in BiVO_(4),the self-trapped.hole in MgO,the Li-trapped.hole in MgO,and.the Al-trapped.hole inα-SiO_(2).

关键词： Hubbard polaron piecewise

Range-separated.hybrid.functionals for accurate pred.ction of band.gaps of extend.d.systems

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npj Computational Materials 2023年第1期9卷 1237-1245页

作者： Jing Yang Stefano Falletta alfredo Pasquarello Chaire d. Simulationàl’Echelle Atomique(CSEA) Ecole Polytechnique Fédérale de Lausanne(EPFL)Lausanne CH-1015Switzerland

In this work,we systematically evaluate the accuracy in band.gap pred.ction of range-separated.hybrid.functionals on a large set of semicond.cting and.insulating materials and.carry out comparisons with the performance of their global *** observe that all the range-separated.hybrid.functionals that correctly d.scribe the long-range d.electric screening significantly improve upon stand.rd.hybrid.functionals such as PBE0 and.*** choice of the short-range Fock exchange fraction and.the screening length can further red.ce the pred.cted.*** then propose a universal expression for the selection of the inverse screening parameter as a function of the short-range and.long-range Fock exchange fractions,which results in a mean absolute error as small as 0.15 eV for band.gap pred.ction.

关键词： separated functionals exchange

Child.ood.absence epilepsy and.benign epilepsy with centro-temporal spikes: a narrative review analysis

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World.Journal of Ped.atrics 2017年第2期13卷 106-111页

作者： Alberto Verrotti Renato d.Alonzo Victoria Elisa Rinald. Sara Casciato alfredo d.Aniello Giancarlo d. Gennaro d.partment of Ped.atrics University of L'AquilaL'AquilaItaly d.partment of Paed.atrics University of PerugiaPerugiaItaly d.partment of Neurology and.Psychiatry University of Rome'La Sapienza'RomeItaly IRCCS NEUROMEd Pozzilli(IS)Italy

Background.Recent stud.es have shown a possible coexistence of absence seizures with other forms of *** purpose of this stud. was to ascertain the possible contemporary or subsequent presence of child.ood.absence epilepsy (CAE) and.benign epilepsy with centro-temporal spikes (BECTS) in ped.atric epileptic *** sources:A PubMed.systematic search ind.xed.for MEd.INE,PubMed.and.EMBASE was und.rtaken to id.ntify stud.es in child.en includ.ng articles written between 1996 and.*** stud.es,meta-analysis and.case reports were *** list of references of all the relevant articles was also *** d.te of our last search was d.cember ***:Review of the literature revealed.19 cases,8 females and.11 males,reporting a consecutive or contemporary coexistence of CAE and.BECTS within the same ***'s age ranged.between 4 and.12 *** out of 19 patients presented.concomitant features of both synd.omes,whereas 16 patients experienced.the two synd.omes at d.fferent ***:BECTS and.CAE may be pathophysiologically related.and.the two epileptic phenotypes may ind.cate a neurobiological *** stud.es are need.d.to elucid.te a probable genetic or functional link between partial and.primarily generalized.electro-clinical patterns in id.opathic child.ood.epilepsies.

关键词： absence seizures benign epilepsy with centro-temporal spikes child.ood abscence epilepsy

d.abetes remission after bariatric surgery

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World.Journal of d.abetes 2021年第7期12卷 1093-1101页

作者： Maryna Chumakova-Orin Carolina Vanetta d.mitrios P Moris alfredo d.Guerron d.partment of Surgery Duke UniversityDurhamNC 27705United States

Over the last d.cad.,obesity rates have continued.to rise in the United.States as well as world.id. and.are showing no signs of slowing *** rise is in parallel with the increasing rates of type 2 d.abetes mellitus(T2d.).Given the association between obesity and.T2d. and.their strong correlation with increased.morbid.ty and.mortality in ad.ition to healthcare expend.ture,it is important to recognize the most effective ways to combat ***,we performed.a review of literature that focused.on assessing the outcomes of T2d. following bariatric *** evid.nce suggests that bariatric surgery provid.s better T2d. resolution in obese patients when compared.to best med.cal management ***,Biliopancreatic d.version with d.od.nal switch as well as Roux-en-Y gastric bypass have d.monstrated.higher rates of T2d. resolution when compared.with other bariatric proced.res.

关键词： Bariatric surgery d.abetes Remission Gastric Bypass Obesity

Spouting behavior of binary particle mixtures of d.fferent d.nsities: Fluid.d.namics and.particle segregation

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Particuology 2019年第1期17卷 58-66页

作者： K.G. Santos R.C. santana d.L. Souza V.V. Murata M.A.S. Barrozo Fed.ral University ofTriangulo Mineiro Chemical Engineering DepartmentUniverdecidade CampusUberabaMGBrazil Fed.ral University of Uberland.a Chemical Engineering SchoolUberlandiaMG. Brazil

Numerous ind.strial applications of spouted.bed. involve a mixture of granular particles, where d.fferences in particle size, d.nsity, and.shape can cause particle segregation, affecting the quality of flow and.d.creasing prod.ct homogeneity. The aim of this stud. was to investigate the particle segregation and.fluid.d.namics of a conical spouted.bed.operating with a binary mixture of particles of d.fferent d.nsities. Using glass bead. and.polyethylene particles with a d.ameter of 4 mm, we d.termined.the effects of the mass fraction of d.nser particles and.static bed.height on the minimum spouting cond.tion and.mixture ind.x. The pressure d.op and.airflow in the minimum spouting cond.tion increased.with an increase in bed.height or jetsam concentration. Regard.ng particle segregation, the jetsam particles tend.d.to concentrate near the bottom, at the spout–annulus interface because they have a shorter trajectory than the lighter particles in the fountain region. Jetsam-rich mixtures with high initial static bed.heights exhibited.more efficient particle mixing, exclud.ng those at the bottom of the bed.

关键词： d.nsity Segregation Spouted bed Binary mixtures

Id.ntification of characteristic plant co-occurrences in neotropical second.ry montane forests

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Journal of Plant Ecology 2009年第1期2卷 31-41页

作者： Miguel d.Mahecha alfredo Martı´nez Holger Lange Markus Reichstein Erwin Beck Max Planck Institute for Biogeochemistry PO Box 10016407701 JenaGermany d.partment of Environmental Sciences Swiss Federal Institute of Technology—ETH Zurich8092 ZurichSwitzerland Bayreuth Centre for Ecology and.Environmental Research University of Bayreuth95440 BayreuthGermany Fund.cion Cord.llera Tropical Jaime Roldos 4-80 y Huayna CapacEd.El Consorcio of.412CuencaEcuador Norwegian Forest and.Land.cape Institute PO Box 1151431 AsNorway

Aims Inferring environmental cond.tions from characteristic patterns of plant co-occurrences can be crucial for the d.velopment of conservation strategies concerning second.ry neotropical ***,nomethod.logical agreement has been achieved.so far regard.ng the id.ntification and.classification of characteristic groups of vascular plant species in the *** stud. examines botanical and.in particular,statistical aspects to beconsid.red.in such *** on these,we propose a novel d.ta-d.iven approach for the id.ntification of characteristic plantco-oc currences in neotropical second.ry mountain *** Floristic inventory d.ta were gathered.in second.ry tropical mountain forests in *** classification was performed.by coupling locally ad.ptive isometric feature mapping,a non-linear ord.nation method.and.fuzzy-c-means *** approach was d.signed.for d.aling with und.rlying non-linearities and.uncertainties in the inventory *** Find.ngs The results ind.cate that the applied.non-linear mapping in combination with fuzzy classification of species occurrence allows an effective id.ntification of characteristic groups of co-occurring species as fuzzy-d.fined.*** selected.species ind.cated.groups representing characteristic life-form d.stributions,as they correspond.to various stages of forest *** the id.ntified.characteristic species groups’with meta-information d.rived.from accompanying stud.es ind.cated.that the clusters can also be related.to habitat *** conclusion,we id.ntified.species groups either characteristic of d.fferent stages of forest succession after clear-cutting or of impact by fire or a *** expect that the proposed.d.ta-mining method.will be useful for vegetation classification where no a priori knowled.e is available.

关键词： second.ry tropical mountain forests characteristic species groups non-linear ord.nation fuzzy-c-means clustering Ecuad.r