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Chinese physics B 2024年第2期33卷 108-114页

作者： U.S.mahabaleshwar G.p.Vanitha l.m.pérez Emad H.Aly I.pop Department of Studies in mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked sheet.With the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is illustrated.The resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity transformations.The transformed differential equations are solved analytically.Impacts of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted graphically.The skin friction and Nusselt number were also evaluated.In addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching one.Further,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O nanofluid.Furthermore,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.pérez-Rodríguez m.Gutiérrez-Roa C.Giménez-Rubio D.Ríos-Ruiz p.Arévalo-Cid m.V.martínez-Huerta A.Zitolo m.J.lázaro D.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOlEIl L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V vs.RHE) in 0.1 m KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

Debaryomyces hansenii supplementation in low fish meal diets promotes growth,modulates microbiota and enhances intestinal condition in juvenile marine fish

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Journal of Animal Science and Biotechnology 2024年第1期15卷 253-276页

作者： Ignasi Sanahuja Alberto Ruiz Joana p.Firmino Felipe E.Reyes-lópez Juan B.Ortiz-Delgado Eva Vallejos-Vidal lluis Tort Dariel Tovar-Ramírez Isabel m.Cerezo miguel A.moriñigo Carmen Sarasquete Enric Gisbert Aquaculture program Institute of Agrifood Research and Technology(IRTA)La Rapita 43540Spain Centro de Biotecnologia Acuicola Universidad de Santiago de ChileSantiagoChile Instituto de Ciencias marinas de Andalucia(ICmAN-CSIC) Avda.Republica Saharaui no 2Campus Universitario Rio San PedroPuerto RealCadiz 11510Spain Nucleo de Investigaciones Aplicadas en Ciencias Veterinarias y Agronomicas Facultad de Medicina Veterinaria y AgronomiaUniversidad de Las AmericasSantiagoChile Department of Cell Biology Physiologyand ImmunologyUniversitat Autonoma de BarcelonaBarcelonaSpain Centro de Investigaciones Biologicas del Noroeste SC CIBNORLa PazMexico Department of microbiology Instituto de Biotecnologia Y Desarrollo Azul(IBYDA)Faculty of SciencesUniversity of Malaga29010 MalagaSpain SCBI Bioinformatic UnitUniversity of Malaga29590 MalagaSpain

Background The development of a sustainable business model with social acceptance,makes necessary to develop new strategies to guarantee the growth,health,and well-being of farmed animals.Debaryomyces hansenii is a yeast species that can be used as a probiotic in aquaculture due to its capacity to i)promote cell proliferation and differen-tiation,ii)have immunostimulatory effects,iii)modulate gut microbiota,and/or iv)enhance the digestive function.To provide inside into the effects of D.hansenii on juveniles of gilthead seabream(Sparus aurata)condition,we inte-grated the evaluation of the main key performance indicators coupled with the integrative analysis of the intestine condition,through histological and microbiota state,and its transcriptomic profiling.Results After 70 days of a nutritional trial in which a diet with low levels of fishmeal(7%)was supplemented with 1.1%of D.hansenii(17.2×10^(5) CFU),an increase of ca.12%in somatic growth was observed together with an improve-ment in feed conversion in fish fed a yeast-supplemented diet.In terms of intestinal condition,this probiotic modu-lated gut microbiota without affecting the intestine cell organization,whereas an increase in the staining intensity of mucins rich in carboxylated and weakly sulphated glycoconjugates coupled with changes in the affinity for certain lectins were noted in goblet cells.Changes in microbiota were characterized by the reduction in abundance of several groups of proteobacteria,especially those characterized as opportunistic groups.The microarrays-based transcrip-tomic analysis found 232 differential expressed genes in the anterior-mid intestine of S.aurata,that were mostly related to metabolic,antioxidant,immune,and symbiotic processes.Conclusions Dietary administration of D.hansenii enhanced somatic growth and improved feed efficiency param-eters,results that were coupled to an improvement of intestinal condition as histochemical and transcriptomic tools indicated.This probiotic yeast stimulated host-microbiota interactions with

关键词： Debaryomyces hansenii Intestine condition low fish meal diet microbiota Transcriptomics Yeast probiotic

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd3+-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257页

作者： C.Y.morassuti A.p.l Silva l.A.O.Nunes S.m.lima l.H.C.Andrade Optical and photothermal Spectroscopy Group (GEOF) Center for Studies in Natural Resources (CERNA)State University of Mato Grosso do Sul(UEMS) Renato Archer Information Technology Center Institute of physics of Sao Carlos University of S?o Paulo

Nd3+-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio（FIR） technique.Nevertheless,at high Nd3+concentrations,energy transfer（ET） processes such as optical reabsorption and cross-relaxation can affect the Nd3+emission,which has been little explored in the literature.Therefore,the present work investigated the use of Nd3+-doped tellurite glass(samples doped with Nd3+at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%) in fluorescence thermometers,in the temperature range from 299 to 371 K.The results indicate a strong dependence of the FIR parameters on the Nd3+concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd3+emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio4F5/2→4I9/2/4F3/2→4I9/2is observed for samples doped with higher amounts of Nd3+.The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd3+ions.

关键词： Fluorescence intensity ratio Judd-Ofelt Nd3+-doped tellurite glass Optical thermometry Rare earths

Radioisotope production using lasers:From basic science to applications

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matter and Radiation at Extremes 2024年第3期9卷 31-44页

作者： m.R.D.Rodrigues A.Bonasera m.Scisciò J.A.pérez-Hernández m.Ehret F.Filippi p.l.Andreoli m.Huault H.larreur D.Singappuli D.molloy D.Raffestin m.Alonzo G.G.Rapisarda D.lattuada G.l.Guardo C.Verona Fe.Consoli G.petringa A.mcNamee m.la Cognata S.palmerini T.Carriere m.Cipriani G.Di Giorgio G.Cristofari R.De Angelis G.A.p.Cirrone D.margarone l.Giuffrida D.Batani p.Nicolai K.Batani R.lera l.Volpe D.Giulietti S.Agarwal m.Krupka S.Singh Fa.Consoli Cyclotron Institute Texas A&M UniversityCollege StationTexas 77840USA laboratori Nazionali del Sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly ENEA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly Centro de láseres pulsados(clpu) VillamayorSpain Universidad de Salamanca SalamancaSpain Centre lasers Intenses et Applications(CElIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 Energy Holdings pty FreshwaterNew South WalesAustralia School of mathematics and physics Queen’s University BelfastBelfastUnited Kingdom Dipartimento di Fisica e Astronomia“E.majorana ”Università di CataniaCataniaItaly Facoltàdi Ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly Dipartimento di Ingegneria Industriale Universitàdi Roma“Tor Vergata”RomaItaly Dipartimento di Fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto Nazionale di Fisica Nucleare Sezione di PerugiaPerugiaItaly ElI Beamlines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic ETSIA Universidad Politécnica de MadridMadridSpain Dipartimento Fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of physics of Czech Academy of Sciences PragueCzech Republic Institute of plasma physics of Czech Academy of Sciences PragueCzech Republic

The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few micrometers.protons with energies of tens of meV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary targets.Under such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical application.The use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on accelerators.In this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other applications.At the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy production.The experiment was performed at the 1 pW laser facility at VegaⅢin Salamanca,Spain.Angular distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium detector.Our results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[Nucl.Instrum.methods phys.Res.,Sect.A 637,164–170(2011)].

关键词： purity estimates backward

Global prevalence and gender inequalities in at least 60 min of self-reported moderate-to-vigorous physical activity 1 or more days per week:An analysis with 707,616 adolescents

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Journal of Sport and Health Science 2024年第5期13卷 709-716页

作者： Raphael H.O.Araujo AndrúO.Werneck Clarice l.martins luciana l.Barboza Rafael m.Tassitano Nicolas Aguilar-Farias Gilmar m.Jesus Robinson Ramírez-Véelez Riki Tesler Adewale l.Oyeyemi Ellen C.m.Silva Robert G.Weaver mark S.Tremblay Javier Brazo-Sayavera Grégore I.mielke Danilo R.p.Silva Graduation program in Health Sciences Londrina State University(UEL)Londrina 86057-970Brazil Center for Epidemiological Research in Nutrition and Health Department of NutritionSchool of Public HealthUniversidade de Sao Paulo(USP)Sao Paulo 01246-904Brazil Department of physical Education Federal University of ParaıbaParaıba 58051-900Brazil Research Centre of physical Activity Health and LeisureFaculty of SportsLaboratory for Integrative and Translational Research in Population Health(ITR)University of PortoPorto 4500Portugal postgraduate program in physical Education University of BrasıliaBrasılia 70910-900Brazil Department of Kinesiology and Community Health University of Illinois at Urbana-ChampaignChampaignIL 61801-3841USA Department of physical Education Sports and RecreationUniversidad de La FronteraTemuco 4680000Chile Department of Health State University of Feira de SantanaFeira de Santana 44036-900Brazil Navarrabiomed Hospital Universitario de Navarra(HUN)Navarra Institute for Health Research(IdiSNA)Universidad Publica de Navarra(UPNA)Pamplona 31006Spain Facultad de Ciencias de la Educacion Unidad Central del Valle del Cauca(UCEVA)TuluaValle del Cauca 763022Colombia Health management Department Faculty of Heath sciencesAriel UniversityAriel 40700Israel College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Arnold School of public Health University of South CarolinaColumbiaSC 29208USA Healthy Active living and Obesity Research Group Children’s Hospital of Eastern Ontario Research InstituteOttawaON K1H 8L1Canada Department of pediatrics University of OttawaOttawaON K1H 8L1Canada Department of Health Sciences Carleton UniversityOttawaON K1S 5B6Canada Department of Sports and Computer Science Universidad Pablo de Olavide(UPO)Seville 41013Spain Centro Universitario Regional Noreste Universidad de la RepublicaRivera 40000Uruguay School of public Health The University of QueenslandBrisbaneQLD 4006Australia Department of physical Education

Background:Guidelines recommend that adolescents should accumulate an average of 60 min per day of moderate-to-vigorous physical activity(mVpA).However,using only this cut-off could hide important information.For instance,from a population-level point of view,increasing physical activity for those with no or low physical activity could provide more health benefits than increasing physical activity for those with intermediate levels.Also,including a more sensitive cut-point of≥1 days per week could be an additional strategy for identifying those with low access/opportunities for physical activity practice.Thus,the current study aims to estimate the prevalence of≥60 min of mVpA≥1 days per week among adolescents globally,and to describe any relevant gender inequalities.methods:We used representative datasets from 146 countries/territories collected between 2003 and 2019.mVpA was self-reported.participants were grouped into younger(≤14 years old)and older(>14 years old)adolescents.Crude poisson regression models were used to identify the relative differences in≥60 min of mVpA≥1 days per week between boys and girls,and random-effects meta-analysis models were used to identify the pooled estimates.Analyses were stratified by country and region.Results:Approximately 80%of both younger and older adolescents reported≥60 min of mVpA≥1 days per week.This prevalence was≥94%in Europe and Central Asia and North America,while the estimates for the other regions wereprevalence of≥60 min of mVpA≥1 days per week was higher among boys than girls,with the largest differences occurring among the oldest adolescents(prevalence ratio_(≤14y)=1.04(95%confidence interval(95%CI)):1.03-1.04)vs.prevalence ratio_(>14y)=1.09(95%CI:1.08-1.10)).Conclusion:Approximately 8 out of 10 adolescents reported accumulating≥60 min of mVpA≥1 days per week,with notable differences between regions.Gender differences were observed in several countries,especially among the oldest adolescents.priorities for physical activity promotion among adolescents

关键词： Global School-based Student Health Survey Health Behaviour Among School-aged Children survey Inequality Surveillance Youth

A comprehensive look at the psychoneuroimmunoendocrinology of spinal cord injury and its progression: mechanisms and clinical opportunities

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military medical Research 2024年第2期11卷 228-267页

作者： miguel A.Ortega Oscar Fraile-martinez Cielo García-montero Sergio Haro miguel Ángel Álvarez-mon Diego De leon-Oliva Ana m.Gomez-lahoz Jorge monserrat mar Atienza-pérez David Díaz Elisa lopez-Dolado melchor Álvarez-mon Department of medicine and medical Specialities University of Alcala28801 Alcala de HenaresSpain Ramón y Cajal Institute of Sanitary Research(IRYCIS) 28034 MadridSpain Department of psychiatry and mental Health Hospital Universitario Infanta Leonor28031 MadridSpain Service of Rehabilitation National Hospital for Paraplegic PatientsCarr.de la PeraledaS/N45004 ToledoSpain Immune System Diseases‑Rheumatology Service and Internal medicine University Hospital Príncipe de Asturias(CIBEREHD)28806 Alcala de HenaresSpain

Spinal cord injury(SCI)is a devastating and disabling medical condition generally caused by a traumatic event(primary injury).This initial trauma is accompanied by a set of biological mechanisms directed to ameliorate neural damage but also exacerbate initial damage(secondary injury).The alterations that occur in the spinal cord have not only local but also systemic consequences and virtually all organs and tissues of the body incur important changes after SCI,explaining the progression and detrimental consequences related to this condition.psychoneuroimmunoendocrinology(pNIE)is a growing area of research aiming to integrate and explore the interactions among the different systems that compose the human organism,considering the mind and the body as a whole.The initial traumatic event and the consequent neurological disruption trigger immune,endocrine,and multisystem dysfunction,which in turn affect the patient's psyche and well-being.In the present review,we will explore the most important local and systemic consequences of SCI from a pNIE perspective,defining the changes occurring in each system and how all these mechanisms are interconnected.Finally,potential clinical approaches derived from this knowledge will also be collectively presented with the aim to develop integrative therapies to maximize the clinical management of these patients.

关键词： Spinal cord injury(SCI) psychoneuroimmunoendocrinology(pNIE) Secondary injury Immunoinflammatory dysfunction Gut microbiota Translational opportunities

Impact of COVID-19-related lifestyle changes on diabetic macular edema

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 97-106页

作者： Bryce p.Johnson Yu-Guang He Zachary m.Robertson Angeline Wang Rafael l.Ufret-Vincenty Department of Ophthalmology UT Southwestern Medical CenterDallasTexas 75390-9057USA

AIm:To assess diabetic macular edema(DmE)progression during the early phases of the COVID-19 pandemic,when severe societal restrictions raised the concern of possible deterioration of health in patients with systemic conditions,particularly those requiring frequent office visits.mETHODS:This is a multicenter retrospective chart review of 370 patients(724 eyes)with an established diagnosis of DmE seen on 3 separate visits between January 2019 and July 2021.period 1 was January 2019 to February 2020(considered pre-COVID-19),period 2 was march 2020 to December 2020(considered the height of the pandemic;highest level of pandemic-related clinical and societal regulations)and period 3 was January 2021 to July 2021(re-adjustment to the new“pandemic norms”).main outcome measures included visual acuity,body mass index(BmI),blood pressure(Bp),hemoglobin A1c(HbA1c),macular thickness,patient adherence to scheduled ophthalmology visits,and DmE treatment(s)received at each visit.To facilitate measurement of macular thickness,each macula was divided into 9 Early Treatment Diabetic Retinopathy Study(ETDRS)-defined macular sectors as measured by OCT imaging.RESUlTS:There was no change of BmI,systolic Bp,and diastolic Bp between any of the time periods.HbA1c showed a very small increase from period 1(7.6%)to period 2(7.8%,p=0.015)and decreased back to 7.6%at period 3(p=0.12).macular thickness decreased for 100%of macular regions.The central macular thickness decreased across all 3 periods from 329.5 to 316.6μm(p=0.0045).After analysis of multiple variables including HbA1c,BmI,adherence to scheduled appointments,different clinic centers,and treatment interventions,there was no easily identifiable subgroup of patients that experienced the increase in DmE.CONClUSION:DmE doesn’t worsen during the COVID-19 pandemic,instead sustaining a very small but statistically significant improvement.While identifying a mechanism behind our findings is beyond the scope of this study,potential explanations may include a delay in retinal changes beyo

关键词： COVID-19 diabetic macular edema diabetic retinopathy optical coherence tomography

post-fire recovery of puya raimondii, vegetation and birds in the puna of Huascarán National park, perú

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Journal of mountain Science 2024年第1期21卷 20-32页

作者： mery l.SUNI Giovana p.VADIllO César ARANA Enoc JARA-pENA letty SAlINAS m.Estela pONCE paul m.RAmSAY plant physiology laboratory Faculty of Biological SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Natural History museum Universidad Nacional Mayor de San MarcosLima 15072Peru Applied phytology laboratory Faculty of Biological SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Department of Statistics Faculty of Mathematical SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Department of Chemical and Biological Sciences Universidad de las Américas PueblaSan Andrés Cholula CP Cholula CP 72810Mexico

A large fire of 233 ha in Huascarán National park in peru provided an opportunity to compare plant and bird responses in burned and nearby unburned zones of the puna. Heights and live diameters of flagship puya raimondii rosettes(assigned to four broad developmental phases), plant communities(66 species in 24 families and nine growth forms) and bird communities(77 species in six trophic guilds) were monitored after the fire. Although no mortality was observed, puya raimondii plants were affected by the fire, losing approximately 60% of their photosynthetic area across all developmental phases, but recovered quickly during the first two years after fire. The comparison of puya rosette recovery after fire was complicated by the changes in live rosette diameter for unburned plants, which showed plasticity of photosynthetic area linked to seasonal and annual fluctuations in precipitation in this relatively dry environment(decreased by 26% for mature adult plants over the study period). Fire caused an immediate change in the density, biomass and composition of vegetation. Although the species present remained similar, their abundances changed significantly immediately after the fire, with notable reductions in dominant tussock grasses. This provided opportunities for other plants, resulting in higher postfire diversity of plant species, genera, families and growth forms. In turn, the changes in vegetation after fire affected the composition of birds according to their trophic guild. Granivores largely disappeared,generalists were mostly unaffected, and other guilds showed a more complex response. As the vegetation recovered, most displaced birds returned within approximately one year.

关键词： Burning plant biomass Trophic guilds Andes Giant rosette plants

A facile strategy for tuning the density of surface-grafted biomolecules for melt extrusion-based additive manufacturing applications

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Bio-Design and manufacturing 2024年第3期7卷 277-291页

作者： I.A.O.Beeren G.Dos Santos p.J.Dijkstra C.mota J.Bauer H.Ferreira Rui l.Reis N.Neves S.Camarero-Espinosa m.B.Baker l.moroni Department of Complex Tissue Regeneration MERLN Institute for Technology-Inspired Regenerative MedicineMaastricht University6229 ER MaastrichtThe Netherlands 3B’s Research Group I3Bs–Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3B’s-pT Government Associate laboratory 4806-909 Braga/GuimarãesPortugal pOlYmAT University of the Basque Country UPV/EHU20018 Donostia/San SebastiánSpain IKERBASQUE Basque Foundation for Science48009 BilbaoSpain

melt extrusion-based additive manufacturing(mE-Am)is a promising technique to fabricate porous scaffolds for tissue engi-neering applications.However,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control cell fate.Grafting of biomolecules on polymeric surfaces of Am scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface density.Here,we report a strategy to tune the surface density of bioactive groups by blending a low molecular weight poly(ε-caprolactone)5k(pCl5k)containing orthogonally reactive azide groups with an unfunctionalized high molecular weight pCl75k at different ratios.Stable porous three-dimensional(3D)scaf-folds were then fabricated using a high weight percentage(75 wt.%)of the low molecular weight pCl 5k.As a proof-of-concept test,we prepared films of three different mass ratios of low and high molecular weight polymers with a thermopress and reacted with an alkynated fluorescent model compound on the surface,yielding a density of 201-561 pmol/cm^(2).Subsequently,a bone morphogenetic protein 2(Bmp-2)-derived peptide was grafted onto the films comprising different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal cells(hmSCs)was assessed.After two weeks of culturing in a basic medium,cells expressed higher levels of Bmp receptor II(BmpRII)on films with the conjugated peptide.In addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-ing the highest peptide density(i.e.,561 pmol/cm^(2)),indicating the importance of the surface density.Taken together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material interface.moreover,we have presented a viable strategy for mE-Am community that desires to tune the bulk and surface functionality via blending of(modified)polymers.Furthermore,the use of alkyne-a

关键词： Additive manufacturing Blending Surface functionalization Surface density Click chemistry Human