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Scale-Covariant Theory of.Gravitation Through Self.Similarity

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Chinese Physics Letters 2012年第5期29卷 33-36页

作者： jose antonio Belinchon department of.Nuclear Molecular and Atomic PhysicsUniversity Complutense of MadridE-28040Spain

We study the scale-covariant theory of.gravitation proposed by Canuto under the self.similar *** considering the matter collineation approach,we deduce the f.rm of.the main quantities and obtain some restrictions on the behavior of.the gauge f.nction,φ(t).We apply the obtained results to study the Bianchi I,Ⅶo,Ⅸ and Kantowsky Sachs models,and arrive at the conclusion that instead of.considering a varying G theory,the solution is only valid f.r a particular value of.the parameter of.the equation of.state,γ,.This leads us to obtain φ(t) =const,and by taking into account the external condition,Gφ2 =const,we may arrive at the conclusion that G=***,all the obtained solutions are the same as the ones obtained in the f.amework of.general relativity.

关键词： const conclusion considering

Monotonic, cyclic and post-cyclic perf.rmances of.single-helix anchor in residual soil of.sandstone

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Journal of.Rock Mechanics and Geotechnical Engineering 2019年第4期11卷 824-836页

作者： jose antonio Schiavon Cristina de Hollanda Cavalcanti Tsuha Luc Thorel department of.Geotechnical Engineering Aeronautics Institute of TechnologySao Jose dos CamposBrazil department of.Geotechnical Engineering University of Sao PauloSao CarlosBrazil If.TTAR GERS DepartmentGeomaterials & Models in Geotechnics LaboratoryBouguenaisFrance

Helical anchors are commonly used in Brazil f.r guyed transmission towers subjected to static and cyclic wind *** most cases,these anchors are installed in tropical residual soil,a micro-structured material in which the shear strength is provided by soil *** installation of.a helical anchor,as the helical plate moves downward into the ground,the soil penetrated is sheared and ***,in this type of.soil,anchor installation af.ects the soil shear strength signif.cantly associated with a bonded ***,the cyclic responses of.helical anchors in this type of.structured soils are rarely *** address this problem,tests were conducted in a Brazilian residual soil to investigate the monotonic,cyclic and post-cyclic perf.rmances of.single-helix *** tests used two instrumented single-helix anchors installed in this typical residual soil of.sandstone,which is f.equently observed in large areas in the southern *** testing results indicate that the disturbance caused by the anchor installation af.ected the monotonic uplif. perf.rmance *** results of.cyclic loading tests also show no signif.cant degradation of.helix bearing resistance and reduced displacement accumulation with increasing load *** is perhaps due to the soil improvement caused by previous loading,which then increases the stif.ness response of.the anchor.

关键词： Helical anchors Tropical residual soil Cyclic loading f.eld load tests

Magnetic f.eld assisted f.uidization:A modif.ed Richardson-Zaki equation

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China Particuology 2007年第1期5卷 61-70页

作者： jose Manuel Valverde antonio Castellanos f.culty of.Physics Universidad de Sevilla Avenida Reina Mercedes s/n 41012 Sevilla Spain

Magnetic particles can be unif.rmly f.uidized by coupling the gas f.ow with an externally imposed magnetic f.eld. Interparticle f.rces generated by the magnetic f.eld cause aggregation of.the particles in chain-like structures pref.rentially oriented along the magnetic f.eld lines. In the present paper, we study the implications of.the f.rmation of.these special types of.aggregates on the empirical Richardson-Zaki （RZ） equation, originally proposed to describe the expansion of.f.uidized beds of.non-aggregated particles. We have addressed two important issues, namely the f.ow regime, which is a f.nction of.the size of.the aggregates, and the ef.ect of.shape and orientation of.the chain-like aggregates with respect to gas f.ow on f.uid drag. We propose a modif.ed RZ equation （MRZE） in which the velocity scale, given by the terminal settling velocity of.the individual aggregates, and the RZ exponent are predetermined as a f.nction of.the chain length. The chain length depends on the ratio of.the magnetic energy to gravitational energy, and is estimated f.om the magnetic f.eld intensity, and particle magnetization, size and density. Predictions of.the MRZE are successf.lly compared with published results in the literature on the expansion of.magnetic particles in the presence of.externally applied magnetic f.elds.

关键词： f.uidization Geldart B Magnetic particles Aggregation Richardson-Zaki equation

Interplay between the glass and the gel transition

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Science China(Physics,Mechanics & Astronomy) 2019年第10期62卷 45-50页

作者： Annalisa f.erro antonio de Candia antonio Coniglio CNR-SPIN c/o Complesso di Monte S.AngeloNapoli 80126Italy Dipartimento di f.sica"Pancini" Universita di Napoli"FedericoⅡ"Complesso di Monte S.AngeloNapoli 80126Italy

By changing the control parameters, many physical systems reach a slow dynamics regime f.llowed by an arrested or a quasiarrested state. Examples, among others, are gels and glasses. In this paper, we discuss some experimental and theoretical results in polymer and colloidal systems, where gel and glass transitions interf.re, and use models f.om Mode Coupling Theory（MCT）to illustrate the rich phenomenology observed. The continuous and the discontinuous transition lines, f.und in the MCT models,are considered suitable to describe respectively the gel and the glass transitions, so we suggest that the interplay between gel and glass may be interpreted in terms of.the f.3 MCT model, clarif.ing also the origin of.logarithmic decays of.en observed in such systems. In particular, the theoretical predictions of.the MCT in the f.3 model are compared with Molecular Dynamics simulations in model systems f.r chemical gels and charged colloids.

关键词： glass gel and sol colloid

Recent Advances on Early-Stage f.re-Warning Systems: Mechanism, Perf.rmance, and Perspective

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Nano-Micro Letters 2022年第12期14卷 106-136页

作者： Xiaolu Li antonio Vazquez-Lopez jose Sanchez del Rio Saez de-Yi Wang IMdeA Materials Institute C/Eric Kandel228906 GetafeMadridSpain E.T.S.de Ingenieros de Caminos Universidad Politecnica de MadridCalle Profesor Aranguren 328040 MadridSpain departamento de Ingenieria Electrica Electronica Automatica y Fisica AplicadaETSIDIUniversidad Politecnica de MadridRonda de Valencia 328012 MadridSpain

Early-stage f.re-warning systems(Ef.Ss)have attracted signif.cant attention owing to their superiority in detecting f.re situations occurring in the pre-combustion *** progress on Ef.Ss has been achieved recently,and they have presented a considerable possibility f.r more evacuation time to control constant unintentional f.re hazards in our daily *** review mainly makes a comprehensive summary of.the current Ef.Ss,including the working mechanisms and their *** to the dif.erent working mechanisms,f.re alarms can be classif.ed into graphene oxide-based f.re alarms,semiconductor-based f.re alarms,thermoelectric-based f.re alarms,and f.re alarms on other working ***,the challenge and prospect f.r Ef.Ss are brief.y provided by comparing the art of.state of.f.re *** work can propose a more comprehensive understanding of.Ef.Ss and a guideline f.r the cutting-edge development direction of.Ef.Ss f.r readers.

关键词： Smart thermosensitive f.re sensors Working mechanism Response time Signal conversion

Thermal and salinity ef.ects on locomotor perf.rmance of.Thoropa taophora tadpoles(Anura,Cycloramphidae)

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Integrative Zoology 2020年第1期15卷 40-54页

作者： antonio C.GALLO Cinthia ABRASILEIRO f.bio Cury de BARROS JoséEduardo de CARVALHO department of.Ecology and Evolutionary Biology Federal University of São PauloDiademaSão PauloBrazil

It is well known that environmental temperature inf.uences several biological f.nctions of.ectotherms,notably in *** high permeability of.anuran skin,associated with the ef.ect of.elevated environmental temperature,potentiates the dehydration process and this combination may restrict locomotor ***pa taophora is an endemic species f.om the Atlantic Rainf.rest whose tadpoles are semiterrestrial and predominantly diurnal,and are f.und in rocky seashores where they are exposed to sea spray and high *** this study we investigated how temperature and salinity conditions af.ect the locomotor perf.rmance in Thoropa taophora *** also assessed how dif.erent osmotic concentrations af.ect the activity of.the metabolic pathways that support muscle *** measured the sprint speed of.tadpoles of.various sizes at dif.erent temperatures and salinities in the *** also measured the activity of.the enzymes pyruvate kinase(PK),lactate dehydrogenase(LDH)and citrate synthase(CS)in dif.erent temperatures and osmotic concentrations,and calculated the thermal sensitivity and the activity constants f.r each *** results showed that,in general,sprint speed decreased with increasing temperature and ***,whereas the ef.ect of.increased salinity was similar in smaller and larger tadpoles,increased temperature had a higher negative impact on sprint speed of.larger tadpoles,thus indicating low thermal sensitivity of.small *** and LDH thermal sensitivities and LDH constant of.activity decreased as the osmolality *** conclusion,the locomotor capacity of.tadpoles was decreased by temperature and salinity,which may be related to a decrease in anaerobic metabolism both in terms of.sensitivity and total energy turnover through enzymatic *** discuss the ecological consequences,including the potential impacts on predator escape behavior promoted by changes in metabolism and locomotor perf.rmance

关键词： amphibians energy metabolism enzyme activity sprint speed

Platelet-rich plasma vs bone marrow aspirate concentrate:An overview of.mechanisms of.action and orthobiologic synergistic ef.ects

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World Journal of.Stem Cells 2021年第2期13卷 155-167页

作者： Joséf.bio Santos Duarte Lana Lucas f.rtado da f.nseca Raf.el da Rocha macedo Tomas Mosaner William Murrell Ashok Kumar joseph Purita Marco antonio Percope de Andrade department of.Orthopedics The Bone and Cartilage InstituteIndaiatuba 13334-170SPBrazil department of.Orthopedics The Federal University of São PauloSão Paulo 04023-062SPBrazil department of.Orthopedics Rede D’Or Unit IFOR HospitalSão Bernardo do Campo 09715-021SPBrazil department of.Orthopaedics Healthpoint UAEAbu Dhabi 00000United Arab Emirates department of.Orthopaedics My Doc Specialist Medical CentreDubai 00000United Arab Emirates department of.Orthopedics Institute of Regenerative MedicineBoca RatonFL 33432United States department of.Orthopaedic Federal University of Minas GeraisBelo Horizonte 31270-901MGBrazil

The use of.orthobiologics as a novel therapy f.r the treatment of.numerous musculoskeletal disorders has increased considerably over the past ***,there are multiple alternatives available as suitable treatments;however,the use of.autologous blood-derived products such as platelet-rich plasma(PRP),bone marrow aspirate(BMA)and BMA concentrate(BMAC),specif.cally,is *** many investigations attempted to demonstrate the ef.ectiveness of.these therapies,even with positive results,the literature lacks standardized protocols and overall accuracy in study designs,which leads to variance and dif.iculty in reproducibility of.*** ef.icacy of.PRP f.r the treatment of.cartilage,bone and muscle tissues is well *** BMAC has generated optimistic results f.r the same purposes,its applicability in clinical trials is still relatively recent when compared to *** products demonstrate the potential to set f.rth reparative processes,each in their own distinct *** combination of.these biological products has been previously proposed,yet little is known about their *** indicates that growth f.ctor,cytokine,and chemokine prof.les seen in both PRP and BMAC vary but are likely to work synergistically to enhance musculoskeletal *** products seem to work well without PRP;however,the addition of.PRP to BMAC has been shown to act as a rich and natural source of.culture medium f.r stem cells located either peripherally or in the bone marrow ***,additional variables associated with the use of.BMAC and PRP in orthopedics must be f.rther evaluated in order to consolidate the ef.icacy of.this therapeutic strategy.

关键词： Orthobiologics Platelet-rich plasma Bone-marrow aspirate Regenerative medicine Musculoskeletal diseases Stem cells

Pan-enteric dysmotility,impaired quality of.lif. and alexithymia in a large group of.patients meeting ROMEⅡ criteria f.r irritable bowel syndrome

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World Journal of.Gastroenterology 2003年第10期9卷 2293-2299页

作者： Piero Portincasa antonio Moschetta Giuseppe Baldassarre Donato f. Altomare Giuseppe Palasciano Section of.Internal Medicine Department of Internal Medicine and Public Medicine(DIMIMP)University Medical SchoolBari Division of.Geriatrics Hospital"Miulli"Acquaviva delle FontiBariItaly Section of.Surgery Department of Emergency and Organ Transplant(DETO)University Medical SchoolBariItaly

AIM:Psychological f.ctors, altered motility and sensation disorders of.the intestine can be variably associated with irritable bowel syndrome (IBS). Such aspects have not been investigated simultaneously. The aim of.this paper was to evaluate gastrointestinal motility and symptoms, psychological spectrum and quality of.lif. in a large group of.IBS patients in southern ***: One hundred IBS patients (f.M=73:27, age 48±2 years, mean±SE) f.lf.lling ROME Ⅱ criteria matched with 100 healthy subjects (f.M=70:30, 45±2 years). Dyspepsia,bowel habit, alexithymia, psycho-af.ective prof.le and quality of.lif. were assessed using specif.c questionnaires. Basally and postprandially, changes in gallbladder volumes and antral areas af.er liquid meal and orocaecal transit time (OCTT)were measured respectively by ultrasonography and H2-breath test. Appetite, satiety, f.llness, nausea, and epigastric pain/discomf.rt were monitored using visual-analogue ***: Compared with controls, IBS patients had increased dyspepsia (score 12.6±0.7 VS 5.1±0.2, P＜0.0001),weekly bowel movements (12.3±0.4 VS 5.5±0.2, P＜0.00001, comparable stool shape), alexithymia (score 59.11.1 VS40.5±1.0, P=0.001), poor quality of.lif. and psychoaf.ective prof.le. IBS patients had normal gallbladderemptying, but delayed gastric emptying (T50:35.5±1.0 VS 26.1±0.6 min, P=0.00001) and OCTT (163.0±5.4 VS96.6±1.8min, P=0.00001). f.llness, nausea, and epigastric pain/discomf.rt were greater in IBS than in ***: ROME Ⅱ IBS patients have a pan-enteric dysmotility with f.equent dyspepsia, associated with psychological morbidity and greatly impaired quality of.*** presence of.alexithymia, a stable trait, is a novel f.nding of.potential interest to detect subgroups of.IBS patients with dif.erent patterns recoveed af.er therapy.

关键词：肠易激综合征述情障碍生活质量临床研究

Urethane Modif.ed Hydrophobic Compact Wood Pulp Paper f.r Oil Spill Cleanup: A Preliminary Study

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Journal of.Renewable Materials 2020年第10期8卷 1257-1268页

作者： Gustavo de Souza Ricardo K.Kramer antonio J.f.Carvalho department of.Materials Engineering Sao Carlos School of Engineering(EESC)University of São Paulo(USP)São PauloBrazil

Oil spills and oil/water wastewater are among the great concerns regarding oil *** technologies f.ce many limitations and in some cases are responsible f.r causing secondary pollution,theref.re there is as seek f.r environmental f.iendly ***,f.om which celluloses are highlighted,are being employed f.r oil/water separation or oil absorbents ***,these membranes are obtained by f.eeze drying of.CNf.cellulose nano-f.brils)suspensions f.llowed by chemical modif.cation f.r hydrophobization,which involves expensive process as chemical vapor deposition and expensive reactants as sylanes,turning these processes hardly ***,we produced a natural porous structure paper f.om eucalyptus pulp f.bers modif.ed by a dipping and heating process in a blocked diisocyanate *** the surf.ce treatment,contact angle with water reached 144°and water absorption reduced seven times,keeping the good oil *** chemical modif.cation process is simple to be perf.rmed and use a very low quantity of.reactant estimated to be less than 0.1 wt%based on *** good mechanical properties of.the material allows its use in non usual conditions which can be of.great importance depending on the environmental conditions.

关键词： Cellulose oil removal hydrophobization water repellency blocked isocyanates