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structural effects induced by dialysis-based purification of carbon nanomaterials

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Nano Materials science 2024年第4期6卷 475-483页

作者： A.D.veloso A.M.Ferraria A.M.Botelho do Rego A.s.viana A.j.s.Fernandes A.j.Fielding R.A.videira M.C.Oliveira CQ-vR and Chemistry Department University of Trás-os-Montes e Alto Douro BsIRG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa Centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics Department University of AveiroCampus de Santiago Faculty of science Pharmacy and Biomolecular SchoolLiverpool John Moores University REQUIMTE/LAQv Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

Dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles （surface groups evolve into more oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanomaterial by electron paramagnetic resonance （EPR） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture Na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： Nanocarbon surface functionalization NMR XPs Hydrophilic carbon Paramagnetic

Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

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journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： j.A.Liu s.j.Liu B.Wang W.B.sun X.j.Liu Z.W.Han College of Materials science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China Weihai Institute for Bionics-jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),W-phase(Mg_(3)Zn_(3)Y_(2)),and LPsO phase(Mg_(12)ZnY).When the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 Mj/m^(3)to 10.97 Mj/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

Biomaterial engineering strategies for modeling the Bruch's membrane in age-related macular degeneration

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Neural Regeneration Research 2024年第12期19卷 2626-2636页

作者： Blanca Molins Andrea Rodríguez víctor Llorenç Alfredo Adán Group of Ocular Inflammation:Clinical and Experimental studies Institut d’Investigacions Biomèdiques AgustíPi I Sunyer(IDIBAPS)BarcelonaSpain Institut Clínic d’Oftalmologia(ICOF) Hospital Clínic BarcelonaSpain

Age-related macular degeneration,a multifactorial inflammatory degenerative retinal disease,ranks as the leading cause of blindness in the ***,there is a scarcity of curative therapies,especially for the atrophic advanced form of age-related macular degeneration,likely due to the lack of models able to fully recapitulate the native structure of the outer blood retinal barrier,the prime to rget tissue of age-related macular *** in vitro systems rely on 2D monocultures unable to adequately reproduce the structure and function of the outer blood retinal barrier,integrated by the dynamic interaction of the retinal pigment epithelium,the Bruch's membrane,and the underlying *** Bruch's membrane provides structu ral and mechanical support and regulates the molecular trafficking in the outer blood retinal barrier,and therefo re adequate Bruch's membrane-mimics are key for the development of physiologically relevant models of the outer blood retinal barrie *** the last years,advances in the field of biomaterial engineering have provided novel approaches to mimic the Bruch's membrane from a variety of *** review provides a discussion of the integrated properties and function of outer blood retinal barrier components in healt hy and age-related macular degeneration status to understand the requirements to adequately fabricate Bruch's membrane biomimetic ***,we discuss novel materials and techniques to fabricate Bruch's membrane-like scaffolds for age-related macular degeneration in vitro modeling,discussing their advantages and challenges with a special focus on the potential of Bruch's membrane-like mimics based on decellularized tissue.

关键词： age-related macular degeneration Bruch's membrane decellularization retinal pigment epithelium scaffold

A novel diurnal and seasonal variation analysis of BTEX in Bengaluru urban area

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Research in Cold and Arid Regions 2024年第1期16卷 14-19页

作者： H.N.sowmya M.Dinamani G.P.shivashankara H.K.Ramaraju B.s.surendra vijaya v.shanbhag R.Prajwal Department of Civil Engineering Dayananda Sagar College of EngineeringBangalore 560078India Department of Chemistry Dayananda Sagar College of EngineeringBangalore 560078India Department of Physics GFGCVijayanagarBengaluru 560040India

In the urban atmosphere of Bengaluru, various volatile organic compounds(vOCs), particularly Benzene,Toluene, Ethylbenzene, and Xylene(BTEX), have shown an increasing trend in concentration. The present research was conducted during summer and monsoon seasons, focusing on Kadubeesanahalli, a high-traffic area within the Bengaluru Metropolitan City. Hourly sample data was collected using a BTEX analyzer(Model GC955-600) and subsequently transformed into daily, monthly, and seasonal values. The study revealed distinct patterns in benzene concentrations. Benzene levels were lowest during the early morning hours, specifically from 1:00 *** 7:00 a.m.. Concentrations then increased from 7:00 a.m. to 9:00 a.m. and again from 4:00 p.m. to 11:00 p.m.,corresponding to the morning and evening peak traffic hours. However, between 10:00 a.m. and 4:00 p.m., the concentration decreased due to reduced traffic levels. These diurnal variations in benzene concentration are influenced by meteorological parameters. Comparing the two seasons, higher concentrations of Benzene, EthylBenzene, and MP-xylene were observed during the summer season. This increase is attributed to the elevated temperatures during summer, which promote the vaporization of BTEX compounds. Conversely, lower BTEX concentrations were recorded during the monsoon season due to the wet deposition process. The observed positive correlation(r > 0.5) among BTEX parameters strongly suggests a common source, most likely originating from vehicular emissions.

关键词： BTEX summer variation Meteorological parameters Correlation

Geochemistry and mineralogy of beach sediments in the northern Gulf of Mexico,Tamaulipas state,Mexico:implication for provenance

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journal of Palaeogeography 2024年第3期13卷 375-400页

作者： Mayank shukla sanjeet K.verma Mayla A.Ramos-vázquez john s.Armstrong-Altrin Karla R.Hernández-Martínez sumit Mishra vivek P.Malviya Héctor Hernández-Mendoza Posgrado de la Division de Geociencias Aplicadas Instituto Potosino de Investigacion Científica y Tecnologica(IPICYT)Camino a la Presa San José2055San Luis Potosí78216Mexico Division de Geociencias Aplicadas Instituto Potosino de Investigación Científica y Tecnologica(IPICYT)Camino a la Presa San Jose 2055San Luis Potosí78216Mexico Universidad Nacional Autonoma de México Instituto de Ciencias del Mar y LimnologíaUnidad de ProcesosOceanicos y CosterosCiudad UniversitariaCiudad de México 04510Mexico Department of Marine sciences Bharathidasan UniversityTiruchirappalli620024Tamil NaduIndia Instituto de Geociencias Universidad Nacional Autonoma de MéxicoBoulevard Juriquilla 300176230JuriquillaQueretaroMexico Department of Applied Geology Dr.Harisingh Gour Central UniversitySagar470002Madhya PradeshIndia Instituto de Investigacion de Zonas Desérticas Universidad Autònoma de San Luis PotosíAltair 200CP 78377San LuisS.L.P.Mexico Universidad del Centro de Mexico Capitán Caldera 75CP 78250San LuisS.L.P.Mexico

Geochemical and mineralogical studies were performed in the La Pesca(LP)and Tesoro Altamira(TA)beach sediments,located in the Tamaulipas state,northern Gulf of *** main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach *** sediments are composed of quartz with small amounts of accessory minerals such as plagioclase,calcite,orthoclase,microcline,and *** beach sediments are classified as fine-grained and very well sorted,however LP has coarse skewed and leptokurtic sediments,whereas TA has fine-skewed and very leptokurtic *** chemical index of weathering(CIW’)indicates intense weathering in the source *** quartz grain microtextures in the LP and TA are classified into mechanical,chemical,and mechanical/chemical *** features such as fractures,pits,percussion marks,abrasion fatigue,and v-shaped marks favor high-energy littoral,fluvial,subaqueous-marine,and aeolian *** chemical features indicate solution pits and crystalline overgrowth,which suggests a silica saturated marine *** mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine *** and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the Mesa Central(MC),sierra Madre Oriental(sMOr)and Oaxaquia *** major and trace element concentrations imply a passive margin setting for the northern Gulf of Mexico,which is consistent with the general geology.

关键词： Beach sediments Geochemistry Mineralogy Provenance Tamaulipas Tectonic setting

The CCD instrument background of the sMILE sXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.W.j.Hubbard O.Hetherington D.j.Hall T.W.Buggey s.Parsons T.Arnold A.Holland C.Pagani s.sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The EsA and CAs sMILE mission orbit is highly elliptical and will pass through multiple radiation *** soft X-ray Imager(sXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the sXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： josep Tomàs víctor Cilleros-Mañé Laia just-Borràs Marta Balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina silvera-simón Manel M.santafé Maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

Effect of age on the standardized ileal amino acid digestibility of soybean meal and canola meal in broilers

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Animal Nutrition 2024年第1期16卷 11-22页

作者： Mukti Barua M.Reza Abdollahi Faegheh Zaefarian Timothy j.Wester Channarayapatna K.Girish Peter v.Chrystal velmurugu Ravindran Monogastric Research Center School of Agriculture and EnvironmentMassey UniversityPalmerston North 4442New Zealand Department of Animal science and Nutrition Faculty of Veterinary MedicineChattogram Veterinary and Animal Sciences UniversityKhulshiChattogram 4225Bangladesh Nutrition and Care Animal NutritionEvonik(SEA)Pte.Ltd609927 Singapore Complete Feed solutions Howick 2145AucklandNew Zealand

standardized ileal digestibility coefficients(sIDC)of nitrogen(N)and amino acids(AA)in two protein sources(soybean meal[sBM]and canola meal[CM])were investigated at six broiler ages(d 7,14,21,28,35,and 42).Two assay diets were formulated to contain either sBM(413 g/kg)or CM(553 g/kg)as the sole dietary AA *** dioxide(5 g/kg)was added as an indigestible marker.A total of 696 male broilers at 1 d old were allotted to 12 replicate cages per age *** assay diet was offered to birds for 4 d prior to the ileal digesta collection on d 7(14 birds/cage),14(12 birds/cage),21(10 birds/cage),28(8 birds/cage),35(8 birds/cage)and 42(6 birds/cage),*** apparent digestibility coefficients were standardized using age-specific basal endogenous AA *** the sBM group,though the sIDC of N tended to be influenced(quadratic;P=0.075)by age,no linear or quadratic response of age effect was observed on the average sIDC of indispensable(IAA)and total AA(TAA).An age effect(quadratic;Ps observed on the average sIDC of dispensable AA(DAA)in sBM with the highest value recorded at d 7,followed by a decrease from d 14 to 28,which increased beyond d *** sIDC of some individual AA(Arg,Thr,Trp,Cys,Pro)were affected(PsIDC of N,average sIDC of IAA,DAA and TAA were influenced(quadratic;PsIDC of N and average sIDC of DAA and TAA were higher from d 7 to 14,declined at d 21,and then increased beyond d *** average sIDC of IAA was low between d 7 and 28 and increased *** sIDC of individual AA were affected(linear or quadratic;Ps by *** age influence on the sIDC AA was variable,depending on the protein source and *** results demonstrate that age-specific sIDC AA data might need consideration in broiler feed formulations.

关键词： Age Amino acid Broiler Digestibility Protein source

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How the Flat space Cosmology Model Correlates the Recombination CMB Temperature of 3000 K with a Redshift of 1100

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journal of Modern Physics 2024年第2期15卷 174-178页

作者： Eugene Terry Tatum U. v. s. seshavatharam Independent Researcher Bowling Green Kentucky USA I-sERvE Hitech City Hyderabad India

This paper shows how the Flat space Cosmology model correlates the recom-bination epoch CMB temperature of 3000 K with a cosmological redshift of 1100. This proof is given in support of the recent publication that the Tatum and seshavatharam Hubble temperature formulae can be derived using the stephan-Boltzmann dispersion law. Thus, as explained herein, the era of high precision Planck scale quantum cosmology has arrived.

关键词： Hubble Constant Cosmic Microwave Background Quantum Cosmology stephan-Boltzmann Upsilon Coupling Constant Flat space Cosmology ΛCDM Cosmology