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Driving factors behind multiple populations

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 172-181页

作者： Ruoyun Huang Baitian Tang Chengyuan Li Doug geisler Mario mateo Ying-Yi Song Holger Baumgardt Julio A.Carballo-Bello Yue Wang Jundan Nie Bruno Dias Joség.Fernández-Trincado School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the guangdong-Hong Kong-Macao greater Bay Area Zhuhai 519082China Departamento de Astronomía Universidad de ConcepcionConcepcionChile Instituto de Investigación Multidisciplinario en Ciencia y Tecnología Universidad de La SerenaLa SerenaChile Departamento de Astronomía Facultad de CienciasUniversidad de La SerenaChile Department of Astronomy University of MichiganAnn Arbor 48109USA David A.Dunlap Department of Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada Dunlap Institute for Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada School of Mathematics and Physics The University of QueenslandSt.Lucia QLD 4072Australia Instituto de Alta Investigación Universidad de TarapacáAricaChile CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Instituto de Astrofísica Departamento de Ciencias FísicasFacultad de Ciencias ExactasUniversidad Andres BelloSantiagoChile Instituto de Astronomía Universidad Católica del NorteAntofagastaChile

Star clusters were historically considered simple stellar populations,with all stars sharing the same age and initial chemical composition.However,the presence of chemical anomalies in globular clusters(gCs),called multiple stellar populations(MPs),has challenged star formation theories in dense environments.Literature studies show that mass,metallicity,and age are likely controlling parameters for the manifestation of MPs.Identifying the limit between clusters with/without MPs in physical parameter space is crucial to reveal the driving mechanism behind their presence.In this study,we look for MP signals in Whiting 1,which is traditionally considered a young gC.Using the Magellan telescope,we obtained low-resolution spectra withinλλ=3850-5500?for eight giants of Whiting 1.We measured the C and N abundances from the CN and CH spectral indices.C and N abundances have variations comparable with their measurement errors(~0.1 dex),suggesting that MPs are absent from Whiting 1.Combining these findings with literature studies,we propose a limit in the metallicity vs.cluster compactness index parameter space,which relatively clearly separates star clusters with/without MPs(gCs/open clusters).This limit is physically motivated.On a larger scale,the galactic environment determines cluster compactness and metallicity,leading to metal-rich,diffuse,old clusters formed ex situ.Our proposed limit also impacts our understanding of the formation of the Sagittarius dwarf galaxy:star clusters formed after the first starburst(age≤8-10 gyr).These clusters are simple stellar populations because the enriched galactic environment is no longer suitable for MP formation.

关键词： stellar galactic galaxy

A Simulation of the Dependence of Tidal Interaction on galaxy Type in Compact groups

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International Journal of Astronomy and Astrophysics 2024年第2期14卷 85-100页

作者： Mark J. Henriksen mateo Mejia Department of Physics University of Maryland Baltimore USA

We have investigated the role that different galaxy types have in galaxy-galaxy interactions in compact groups. N-body simulations of 6 galaxies consisting of a differing mixture of galaxy types were run to compare the relative importance of galaxy population demographic on evolution. Three different groups with differing galaxy content were tested: all spiral, a single elliptical and 50% elliptical. Tidal interaction strength and duration were recorded to assess the importance of an interaction. A group with an equal number of spiral and elliptical galaxies has some of the longest and strongest interactions with elliptical-elliptical interactions being most significant. These elliptical-elliptical interactions are not dominated by a single large event but consist of multiple interactions. Elliptical galaxies tidally interacting with spiral galaxies, have the next strongest interaction events. For the case when a group only has a single elliptical, the largest magnitude tidal interaction is an elliptical on a spiral. Spirals interact with each other through many small interactions. For a spiral only group, the interactions are the weakest compared to the other group types. These spiral interactions are not dominated by any singular event that might be expected to lead to a merger but are more of an ongoing harassment. These results suggest that within a compact group, early type galaxies will not form via merger out of an assemblage of spiral galaxies but rather that compact groups, in effect form around an early type galaxy.

关键词： galaxy groups galaxy Clusters galaxy Evolution N-Body Simulations

Camalote grass (Paspalum fasciculatum Willd) as a Sustainable Raw Material for the Production of Lignocellulosic Ethanol

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Journal of Sustainable Bioenergy Systems 2024年第2期14卷 23-33页

作者： María Luz May-Reyes Cintya Valerio-Cárdenas gloria Ivette Bolio-López Manuel mateo Hernández-Villegas Miguel Ángel Velázquez-Carmona Patricia De la Cruz-Burelo Research and Postgraduate Coordination Universidad Popular de la Chontalpa Crdenas Tabasco Mexico

The current trend of replacing a percentage of gasoline with ethanol has promoted the development of new processes for its production from lignocellulosic biomass. This work reports the production of ethanol from the Camalote grass (Paspalum fasciculatum Willd). The lignocellulosic biomass was subjected to acid hydrolysis at 125C and 15 psi with H2SO4 concentrations at 5%, 10%, and 20%, obtaining an average of reducing sugars (pentoses and hexoses) from the hydrolyzed juice with 12.3%, 10%, and 17% Brix, respectively. The sugars were fermented using yeast of the Saccharomyces cerevisiae at 30C for 48 hours. Finally, the ethanol was distilled at 78C, and the average yields were obtained through analysis of variance with a 95% confidence level. The values indicate that there is a significant difference (p > 0.05), the Tukey study shows that all the % v/v averages are different from each other. For H2SO4 concentration at 5% (10.33 ± 2), H2SO4 at 10% (9.33 ± 1.8), and H2SO4 at 20% (6.33 ± 2). The acidity analysis for the ethanol obtained from each treatment gave a value of 1.8 mg/L of acetic acid in all cases.

关键词： Lignocellulosic Ethanol Lignocellulosic Biomass Camalote grass Acid Hydrolysis Energy Crops

Random noise stimulation in the treatment of patients with neurological disorders

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Neural Regeneration Research 2022年第12期17卷 2557-2562页

作者： mateo A.Herrera-Murillo Mario Treviño Elias Manjarrez Facultad de Medicina Plan de Estudios Combinados en Medicina(PECEM)UNAMCircuito InteriorCiudad UniversitariaAv.UniversidadCiudad de MéxicoMéxico Instituto de Neurociencias Universidad de GuadalajaraGuadalajaraJaliscoMéxico Instituto de Fisiología Benemérita Universidad Autónoma de PueblaPueblaMéxico

Random noise stimulation technique involves applying any form of energy(for instance,light,mechanical,electrical,sound)with unpredictable intensities through time to the brain or sensory receptors to enhance sensory,motor,or cognitive functions.Random noise stimulation initially employed mechanical noise in auditory and cutaneous stimuli,but electrical energies applied to the brain or the skin are becoming more frequent,with a series of clinical applications.Indeed,recent evidence shows that transcranial random noise stimulation can increase corticospinal excitability,improve cognitive/motor performance,and produce beneficial aftereffects at the behavioral and psychological levels.Here,we present a narrative review about the potential uses of random noise stimulation to treat neurological disorders,including attention deficit hyperactivity disorder,schizophrenia,amblyopia,myopia,tinnitus,multiple sclerosis,post-stroke,vestibular-postural disorders,and sensitivity loss.Many of the reviewed studies reveal that the optimal way to deliver random noise stimulation-based therapies is with the concomitant use of neurological and neuropsychological assessments to validate the beneficial aftereffects.In addition,we highlight the requirement of more randomized controlled trials and more physiological studies of random noise stimulation to discover another optimal way to perform the random noise stimulation interventions.

关键词： auditory noise mechanical noise neurological disorders neuronal noise noise galvanic vestibular stimulation non-invasive brain stimulation transcranial electrical stimulation transcranial random noise stimulation

Expression of miR‑138 in cryopreserved bovine sperm is related to their fertility potential

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Journal of Animal Science and Biotechnology 2023年第6期14卷 2383-2394页

作者： Albert Salas‑Huetos Jordi Ribas‑Maynou Yentel mateo‑Otero Carolina Tamargo Marc Llavanera Marc Yeste Unit of Cell Biology Department of BiologyFaculty of SciencesUniversity of GironaGirona 17003Spain. Biotechnology of Animal and Human Reproduction(TechnoSperm) Institute of Food and Agricultural TechnologyUniversity of GironaGirona 17003Spain. Department of Nutrition Harvard T.H.Chan School of Public HealthHarvard UniversityBostonMA 02115USA. Consorcio CIBER M.P.Fisiopatologia de la Obesidad y Nutricion(CIBERobn)Instituto de Salud Carlos III(ISCIII)Madrid 28029Spain. Present Address:Unit of Preventive Medicine and Public Health Faculty of Medicine and Health SciencesUniversitat Rovira i VirgiliReus 43201Spain. Department of Animal Selection and Reproduction The Regional Agri-Food Research and Development Service of Asturias(SERIDA)Gijon 33394Spain. Catalan Institution for Research and Advanced Studies(ICREA) Barcelona 08010Spain.

Background MicroRNAs(miRNAs)are small,single-stranded,non-coding RNA molecules of 22–24 nucleotides that regulate gene expression.In the last decade,miRNAs have been described in sperm of several mammals,including cattle.It is known that miRNAs can act as key gene regulators of early embryogenesis in mice and humans;however,little is known about the content,expression,and function of sperm-borne miRNAs in early bovine embryo.In this study,total sperm RNA was isolated from 29 cryopreserved sperm samples(each coming from a separate bull)using a RNeasy kit and treatment with DNase I.RNA concentration and purity were determined through an Epoch spectrophotometer and an Agilent Bioanalyzer.The expression of 10 candidate miRNAs in bovine sperm(bta-miR-10a,bta-miR-10b,bta-miR-138,bta-miR-146b,bta-miR-19b,bta-miR-26a,bta-miR-34a,bta-miR-449a,bta-miR-495 and btamiR-7),previously identified in testis and/or epididymis,was evaluated with RT-qPCR.The cel-miR-39-3p was used as a spike-in exogenous control.Nonparametric Mann–Whitney tests were run to evaluate which miRNAs were differentially expressed between bulls with high fertility[HF;non-return rates(NRR)ranging from 39.5 to 43.5]and those with subfertility(SF;NRR ranging from 33.3 to 39.3).Several sperm functionality parameters(e.g.,viability,membrane stability or oxygen consumption,among others)were measured by multiplexing flow cytometry and oxygen sensing technologies.Results RNA concentration and purity(260/280 nm ratio)(mean±SD)from the 29 samples were 99.3±84.6 ng/μL and 1.97±0.72,respectively.Bioanalyzer results confirmed the lack of RNA from somatic cells.In terms of the presence or absence of miRNAs,and after applying the Livak method,8 out of 10 miRNAs(bta-miR-10b,-138,-146b,-19b,-26a,-449a,-495,-7)were consistently detected in bovine sperm,whereas the other two(bta-miR-10a,and-34a)were absent.Interestingly,the relative expression of one miRNA(bta-miR-138)in sperm was significantly lower in the SF than in the HF group(P=0.038).In addition to being associated to

关键词： Bovine Fertility miRNAs Sperm

The first cavefish in the Dinaric Karst?Cave colonization made possible by phenotypic plasticity in Telestes karsticus

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Zoological Research 2023年第4期44卷 821-833页

作者： mateoČupić Zoran Marčić Marko Lukić Romana gračan Helena Bilandžija Division of Molecular Biology Ruđer BoškovićInstituteZagreb 10000Croatia Department of Biology Faculty of ScienceZagreb 10000Croatia Croatian Biospeleological Society Zagreb 10000Croatia

Cave animals are an excellent model system for studying adaptive evolution.At present,however,little is known about the mechanisms that enable surface colonizers to survive in the challenging environment of caves.One possibility is that these species have the necessary genetic background to respond with plastic changes to the pressures of underground habitats.To gain insight into this process,we conducted a comparative study with the fish species Telestes karsticus,which occurs in a hydrological system consisting of an interconnected stream and a cave.Results showed that T.karsticus resided year-round and spawned in Sušik cave,making it the first known cavefish in the Dinaric Karst.Cave and surface populations differed in morphological and physiological characteristics,as well as in patterns of gene expression without any evidence of genetic divergence.To test whether observed trait differences were plastic or genetic,we placed adult fish from both populations under light/dark or constant dark conditions.Common laboratory conditions erased all morphometric differences between the two morphs,suggesting phenotypic plasticity is driving the divergence of shape and size in wild fish.Lighter pigmentation and increased fat deposition exhibited by cave individuals were also observed in surface fish kept in the dark in the laboratory.Our study also revealed that specialized cave traits were not solely attributed to developmental plasticity,but also arose from adult responses,including acclimatization.Thus,we conclude that T.karsticus can adapt to cave conditions,with phenotypic plasticity playing an important role in the process of cave colonization.

关键词： Maladaptive and adaptive phenotypic plasticity Troglobionts and stygobionts Endemic leuciscid fish Acclimatization European cavefish Cave adaptations gene expression differences

Determination of double-and single-stranded DNA breaks in bovine sperm is predictive of their fertilizing capacity

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Journal of Animal Science and Biotechnology 2023年第1期14卷 134-151页

作者： Jordi Ribas‑Maynou Ariadna Delgado‑Bermúdez Yentel mateo‑Otero Estel Vinolas Carlos O.Hidalgo WSteven Ward Marc Yeste Biotechnology of Animal and Human Reproduction(TechnoSperm) Faculty of SciencesInstitute of Food and Agricultural TechnologyUniversity of GironaC/Maria Aurèlia Campany69ES‑17003 GironaSpain. Unit of Cell Biology Department of BiologyFaculty of SciencesUniversity of GironaES‑17003 GironaSpain. Institute for Biogenesis Research Department of AnatomyBiochemistry&PhysiologyJohn A.Burns School of MedicineUniversity of Hawaii at ManoaHonoluluHI 96822USA. Department of Animal Selection and Reproduction The Regional Agri-Food Research and Development Service of Asturias(SERIDA)ES‑33394 GijónSpain. Catalan Institution for Research and Advanced Studies(ICREA) ES‑08010 BarcelonaSpain.

Background:The analysis of chromatin integrity has become an important determinant of sperm quality.In frozenthawed bovine sperm,neither the sequence of post-thaw injury events nor the dynamics of different types of sperm DNA breaks are well understood.The aim of the present work was to describe such sperm degradation aftermath focusing on DNA damage dynamics,and to assess if this parameter can predict pregnancy rates in cattle.Results:A total of 75 cryopreserved ejaculates from 25 Holstein bulls were evaluated at two post-thawing periods(0-2 h and 2-4 h),analyzing global and double-stranded DNA damage through alkaline and neutral Comet assays,chromatin deprotamination and decondensation,sperm motility,viability,acrosomal status,and intracellular levels of total ROS,superoxides and calcium.Insemination of 59,605 females was conducted using sperm from the same bulls,thus obtaining the non-return to estrus rates after 90 d(NRR).Results showed an increased rate of double-stranded breaks in the first period(0-2 h:1.29±1.01%/h vs.2-4 h:0.13±1.37%/h;Pgh single-stranded breaks was higher in the second period(0-2 h:3.52±7.77%/h vs.2-4h:21.06±11.69%/h;Pgarding sperm physiology,viability decrease rate was different between the two periods(0-2 h:-4.49±1.79%/h vs.2-4 h:-2.50±3.39%/h;P=0.032),but the progressive motility decrease rate was constant throughout post-thawing incubation(0-2 h:-4.70±3.42%/h vs.2-4 h:-1.89±2.97%/h;P>0.05).Finally,whereas no correlations between bull fertility and any dynamic parameter were found,there were correlations between the NRR and the basal percentage of highly-damaged sperm assessed with the alkaline Comet(Rs=-0.563,P=0.003),between NRR and basal progressive motility(Rs=0.511,P=0.009),and between NRR and sperm with high ROS at 4 h post-thaw(Rs=0.564,P=0.003).Conclusion:The statistically significant correlations found between intracellular ROS,sperm viability,sperm motility,DNA damage and chromatin deprotamination suggested a sequen

关键词： Cattle Chromatin Comet test DNA damage Fertility Sperm Sperm quality

Peri-implant femoral fractures:Challenges,outcomes,and proposal of a treatment algorithm

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Chinese Journal of Traumatology 2023年第4期26卷 211-216页

作者： Fernando Bidolegui Sebastian Pereira mateo Alzate Munera german garabano Cesar A.Pesciallo Robinson Esteves Pires Vincenzo giordano Orthopaedics and Trauma Surgery Department Sirio Libanes HospitalBuenos AiresArgentina Orthopaedics and Trauma Surgery Department British Hospital of Buenos AiresBuenos AiresArgentina Department of the Locomotor Apparatus Federal University of Minas GeraisBelo HorizonteBrazil Orthopedics and Traumatology Prof.Nova Monteiro Hospital Municipal Miguel CoutoRio de JaneiroBrazil

Purpose:Non-prosthetic peri-implant fractures are challenging injuries.Multiple factors must be care-fully evaluated for an adequate therapeutic strategy,such as the state of bone healing,the type of implant,the time and performed personnel of previous surgery,and the stability of fixation.The aim of this study is to propose a rationale for the treatment.Methods:The peri-implant femoral fractures(PIFFs)system,a therapeutic algorithm was developed for the management of all patients presenting a subtype A PIFF,based on the type of the original implant(extra-vs.intra-medulllary),implant length and fracture location.The adequacy and reliability of the proposed algorithm and the fracture healing process were assessed at the last clinical follow-up using the Parker mobility score and radiological assessment,respectively.In addition,all complications were noticed.Continuous variables were expressed as mean and standard deviation,or median and range according to their distribution.Categorical variables were expressed as frequency and percentages.Results:This is a retrospective case series of 33 PIFFs,and the mean post-operative Parker mobility score was(5.60±2.54)points.Five patients(15.1%)achieved complete mobility without aids(9 points)and 1(3.0%)patient was not able to walk.Two other patients(6.1%)were non-ambulatory prior to PPIF.The mean follow-up was(21.51±9.12)months(range 6-48 months).There were 7(21.2%)complications equally distributed between patients managed either with nailing or plating.There were no cases of nonunion or mechanical failure of the original implant.Conclusion:The proposed treatment algorithm shows adequate,reliable and straightforward to assist the orthopaedic trauma surgeon on the difficult decision-making process regarding the management of PIFF occurring in previously healed fractures.In addition,it may become a useful tool to optimize the use of the classification,thus potentially improving the outcomes and minimizing complications.

关键词： Peri-implant femoral fracture Peri-osteosynthesis fracture Femurfracture Treatment algorithm

Turning carbon dots into selenium bearing nanoplatforms with in vitro gPx-like activity and pro-oxidant activity

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Nano Research 2023年第5期16卷 7784-7791页

作者： Laura Perez-garrido Mariano Ortega-Muñoz Fernando Hernandez-mateo F.Javier Lopez-Jaramillo Francisco Santoyo-gonzalez Department of Organic Chemistry Biotechnology InstituteSchool of SciencesCampus Fuentenueva snUniversity of Granada18071-GranadaSpain

Selenium(Se)has been defined as the“Janus element”,with one face showing antioxidant activity and the other pro-oxidant activity.The biological effect of Se depends on both dose and speciation.Se nanoparticles are attracting major interest,although their large-scale preparation for biomedical applications is not trivial.We hypothesize that acid anhydride-coated carbon dots(AACD)are an attractive platform for preparing nanoparticles containing chemically defined Se.The reaction of AA-CD with 3-selenocyanatopropan-1-amine yields carbon dots bearing selenocyanate and carboxylate groups(CD-SeCN)that allow for tuning the hydrosolubility.CD-SeCN has a Se content of 0.36μmol per mg of nanoparticles,they show the typical photoluminescence of carbon dots.The selenocyanate groups(SeCN)exhibited glutathione peroxidase-like activity and cytotoxicity.Data show that antioxidant behavior differs between normal and tumor cells,the evaluation on HEK293 and A549 cells reveals that the toxicity of CD-SeCN depends on dose,time,intracellular glutathione(gSH)content.The toxicity of CD-SeCN decreases with the time of incubation and the cell death mechanism switches from necrosis to apoptosis,indicating that CD-SeCN is neutralized.Additionally,high levels of intracellular gSH exert a protective effect.These results support a pharmacological potential in cancers with low levels of intracellular gSH.The use of AA-CD as nanoplatforms is a general strategy that paves the way for the engineering of advanced nanosystems.

关键词： selenium nanoparticles carbon dots glutathione peroxidase-like activity Janus element nanomedicine