Bioethics is the argumentative discipline of decisions and actions that reduce conflicts of interest,dilemmas,or asymmetries between the parties involved in biomedical research.The objective of this work was to review...Bioethics is the argumentative discipline of decisions and actions that reduce conflicts of interest,dilemmas,or asymmetries between the parties involved in biomedical research.The objective of this work was to review and compare the dimensions used by bioethics in the communicative management of the pandemic,namely:risk,vulnerability,resilience,and stigma.A documentary,exploratory,transversal,and retrospective work was carried out with a sample of sources indexed in international repositories,considering the search by keywords and the publication period from 2020 to 2024.The results demonstrate the prevalence of supply,contagion,symptoms,and help against COVID-19.展开更多
We extend a well-known mass-gap equation for pure gluodynamics in global colour models(formulated in equal-time quantization in Coulomb gauge)to one in which gluons are split into two sets,each exhibiting different ma...We extend a well-known mass-gap equation for pure gluodynamics in global colour models(formulated in equal-time quantization in Coulomb gauge)to one in which gluons are split into two sets,each exhibiting different masses.If the theory is SU(N)×SU(M)with gluons in both groups having identical couplings(as suggested by Grand Unification arguments at large scales)it is immediate to see that different masses are generated for each subgroup.This global symmetry is not broken,but the split masses erase accidental symmetries that might be present due to the two couplings being the same at a large scale,such as SU(N×M)or similar.We also numerically explore a couple of low-dimensional examples of simple Lie groups,but in spite of the system of equations having a form that would seem to allow spontaneous symmetry breaking,it is not triggered for these groups whose algebra has no ideal,and the dispersion relations for the various gluons converge to the same form.展开更多
Fish constitutes the main protein source for the Amazonian population.However,the impact of different anthropogenic activities on trace element and metal accumulation in fish and their risks for human health at a regi...Fish constitutes the main protein source for the Amazonian population.However,the impact of different anthropogenic activities on trace element and metal accumulation in fish and their risks for human health at a regional scale remain largely unexplored.Here we assessed exposure levels of 10 trace elements andmetals(Cr,Mn,Fe,Ni,Cu,Zn,As,Cd,Pb,and Hg)in 56 samples belonging to 11 different species of fish from the Brazilian Amazon.We studied the relationship between exposure levels,fish origin,and fish feeding habits,and assessed toxicological and carcinogenic risks for the Amazonian population.No significant correlation was found between sampling site and exposure levels to the studied elements,but a significant difference was found between the accumulation of some metals and the position of the fish species in the food chain.The concentrations of Cr and Hg in fish flesh were found to exceed the Brazilian limits for human consumption.This study shows that current fish consumption patterns can lead to estimated daily intakes of Hg,As and Cr that exceed the oral reference dose,thus posing a toxicological concern.Furthermore,carcinogenic risks may be expected due to the continued exposure to Cr and As.The results of this study show that the consumption of wild caught fish in the Amazon region should be controlled.Moreover,continued monitoring of trace element and metal contamination in fish and on the health of the Amazonian population is recommended,particularly for riverine and indigenous communities.展开更多
Multiparent advanced generation inter-cross(MAGIC)populations improve the accuracy of quantitative trait loci mapping compared to biparental populations by increasing diversity and reducing linkage disequilibrium betw...Multiparent advanced generation inter-cross(MAGIC)populations improve the accuracy of quantitative trait loci mapping compared to biparental populations by increasing diversity and reducing linkage disequilibrium between variants.Here we describe the development of two MAGIC populations derived from a cross of 11 founder lines from the INTA(National Institute for Agricultural Technology in Argentina)sunflower breeding program.The founder lines are fertility maintainer inbred lines that exhibit genetic diversity in several traits,including flowering cycle,plant architecture,disease resistance,oil content and oil quality.The crossing scheme applied follows the design of two-way,four-way and eight-way crosses with a modification to increase the number of recombinations and shorten the linkage disequilibrium.Phenotyping a subset of F_(2)families and F_5 lines for different traits shows an increase in the diversity of the analyzed traits compared to the parental lines.In addition,we identified lines with transgressive segregation for Sunflower Verticillium Wilt resistance.These results confirm that the MAGIC populations will serve as unique genetic and genomic resources to better characterize the genetics of complex traits and identify potentially superior alleles for sunflower breeding.It will also enrich the gene pool of fertility maintainers(A/B line)of the sunflower germplasm and facilitate the introduction of new breeding methods to select female parents for use in AxR combinations to obtain superior sunflower hybrids.展开更多
Advanced mesenchymal stromal cell-based therapies for neurodegenerative diseases are widely investigated in preclinical models.Mesenchymal stromal cells are well positioned as therapeutics because they address the und...Advanced mesenchymal stromal cell-based therapies for neurodegenerative diseases are widely investigated in preclinical models.Mesenchymal stromal cells are well positioned as therapeutics because they address the underlying mechanisms of neurodegeneration,namely trophic factor deprivation and neuroinflammation.Most studies have focused on the beneficial effects of mesenchymal stromal cell transplantation on neuronal survival or functional improvement.However,little attention has been paid to the interaction between mesenchymal stromal cells and the host immune system due to the immunomodulatory properties of mesenchymal stromal cells and the long-held belief of the immunoprivileged status of the central nervous system.Here,we review the crosstalk between mesenchymal stromal cells and the immune system in general and in the context of the central nervous system,focusing on recent work in the retina and the importance of the type of transplantation.展开更多
Protected areas(PA)have proven to be one of the best ways to conserve biodiversity against environmental changes.Amphibians are considered the most threatened group,with habitat loss due to deforestation identified as...Protected areas(PA)have proven to be one of the best ways to conserve biodiversity against environmental changes.Amphibians are considered the most threatened group,with habitat loss due to deforestation identified as their major threat.Here,we assessed for each PA of the American continent:1)amphibian’s occurrence(Global Biodiversity Information Facility(GBIF)vs.International Union for Conservation of Nature(IUCN)data);2)temperature velocity and estimated the climate residence time,and using the latest models of the land future use;3)we estimated the changes of natural vs.modified cover in three future scenarios.Amphibian occurrence showed differences between databases,while GBIF data shows that 52%of the amphibian species occurring in the continent are in PA,based on IUCN data,85%are protected.Results from climate change show a low pace of climate velocity during the last century that is maintained in the green scenario(SSP126).However,change in temperature increases in rate in the rest of the scenarios,with scenario SSP58 showing the highest velocity of temperature change.Future estimates of residence times in PA show that lower levels as emission scenarios tend to be higher.These results are worrisome since climate lag,specifically temperature increase over the PA will probably affect amphibian communities as shown in previous studies.Changes in climate patterns have a direct—mostly negative—impact on amphibians’ability to disperse and reproduce.The results of land use change were unexpected,since the categories showed minimal changes.However,the data on urbanization changes do not seem to be reflecting the trends of other databases,which may be causing artifacts in the comparisons in the future models of land use.Further research will be necessary to evaluate the extent of similarities and differences in future projections of land use including urbanization and human population between different databases.展开更多
Particulate organic matter(POM)is an important energy source for aquatic consumers,understanding its origin and composition is essential for understanding the energetic dynamics of aquatic environments.The aim of this...Particulate organic matter(POM)is an important energy source for aquatic consumers,understanding its origin and composition is essential for understanding the energetic dynamics of aquatic environments.The aim of this study was to analyze the relationship between POM and phytoplankton(isotopic values and chlorophyll concentration)and abiotic variables during dry and rainy seasons.Sampling was conducted in rivers and lagoons in the floodplain of the Upper ParanáRiver.We found a greater difference in ^(δ13)C values of POM between sampling points than between seasons,indicating that the composition of regional sources influences the composition of POM more than dry and rainy seasons.In addition,the concentration of chlorophyll during the dry season was positively correlated with ^(δ13)C values during that rainy period.Additionally,we found a relationship between factors limiting the growth of phytoplankton and ^(δ13)C values of POM,such as phosphate ions,indicating that variables that regulate phytoplankton growth tend to influence the composition of POM in river floodplains.Therefore,maintaining the variables that regulate the phytoplankton community is of fundamental importance for the composition of POM,an important energy source in aquatic environments.展开更多
Because of environmental constraints,beef cattle was for more than a century the only viable farming option in the extensive semiarid and subhumid lands of Argentina and the main source of nutrients for humans as well...Because of environmental constraints,beef cattle was for more than a century the only viable farming option in the extensive semiarid and subhumid lands of Argentina and the main source of nutrients for humans as well.However,a growing concern and criticism have risen today about its possible negative impact on the climate and the environment.These worries tend to affect current public opinions,national policies,and international trade.Based on 40 beef cattle farms scattered across different semiarid and subhumid regions of Argentina,here we evaluated the impact of extensive cattle production on carbon,water,and nutrient pollution.Life-Cycle Assessment(LCA)and Land-Based Assessment(LBA)were the two approaches we used here to compare the environmental impact of beef production.While the environmental footprint(EF)resulting from LCA expresses the impact per unit of food,the environmental balance(EB),derived from LBA,aims at quantifying the impact per unit of land.As such,the EB considers both negative and positive impacts on the farm as an integrated system.Following standardized procedures,we evaluated EF and EB up to the farm gate,leaving aside delocalized post-farm impacts such as those of processing,packaging,and transportation that occur beyond the farm gate.In agreement with previous evidence,our results show that the EF tends to decrease as per-head production increases.Correlation coefficients and statistical significance were the following for carbon(R=−0.574;p<0.01),water(R=−0.561;p<0.01),and N(R=−0.704;p<0.01)and Phosphorus(P)pollution(R=−0.802;p<0.01)footprints.On the contrary,the EB seems to be highly sensitive,and as per-hectare beef production increases.Correlations were the following for carbon emissions(CE:R=0.955;p<0.01),water consumption(WC:R=0.822;p<0.01),nitrogen excretion(NE:R=0.948;p<0.01)and phosphorus excretion(PE:R=0.945;p<0.01).What our results suggest is that the notion of EF is useful to evaluate the environmental impact in intensive beef production systems,and the EB is suitable to assess the impact of the extensive ones.In practice,both approaches provide different perspectives on the environmental-impact problem and they should be complementary used.We concluded that the methodological rigidity of EF does not allow proper discrimination among farms in the extensive systems.On the contrary,the EB approach tended to be highly sensitive to detecting differences between individual farms and farmers,thus allowing the identification of successful options for extensive beef production in terms of public image,policy-making,and commercial opportunities.展开更多
As the sole obligate symbiotic birds in Africa,oxpeckers offer a unique model for studying symbiotic relationships.Due to the multitrophic level they occupy and the context dependent foraging behavior they exhibit,the...As the sole obligate symbiotic birds in Africa,oxpeckers offer a unique model for studying symbiotic relationships.Due to the multitrophic level they occupy and the context dependent foraging behavior they exhibit,the type of symbiotic relationship can be variable.In addition to providing a cleaning service to the host by removing ticks,oxpeckers frequently feed on blood,mucus,and saliva,inflicting potential damage on the host.Here,we used DNA metabarcoding on faecal samples to analyze the taxonomic composition of the trophic interactions of the Yellow-billed Oxpecker(Buphagus africanus)and Red-billed Oxpecker(B.erythrorhynchus)in northeastern Namibia.In contrast to conventional methods,DNA metabarcoding allows for a detailed identification of dietary resources encompassing both mammal hosts and consumed arthropods within the same samples.With this information,we examined differences in the diet composition between oxpecker species and localities,as well as the co-occurrence between host and arthropod species.Our findings revealed that oxpeckers predominantly source their diet from mammals,ticks,and flies;however,ticks and flies rarely co-occur in the diet of an individual.We observed variability among individuals in their feeding ecology,which is strongly correlated with locality and,to a lesser extent,with the mammal host.We noted a high degree of mobility between hosts within relatively short periods,with 32%of the samples showing traces of at least two mammal hosts.This study illustrates the dynamic foraging behavior of these specialized symbiotic birds,shedding light on their potential role in pest control services and disease transmission.展开更多
Hydropower development has become an important driver of habitat loss and fragmentation across lowland tropical forests.Despite ample evidence on the detrimental effects of insular habitat fragmentation on biodiversit...Hydropower development has become an important driver of habitat loss and fragmentation across lowland tropical forests.Despite ample evidence on the detrimental effects of insular habitat fragmentation on biodiversity,invertebrate taxa,that may be critical to ecosystem functioning,have been overlooked.We assessed the assemblage-level responses of social wasps to forest insularization induced by the Balbina Hydroelectric Dam in Central Brazilian Amazonia.Employing Malaise trapping,we captured wasps on 27 forest islands and three continuous forests.We constructed Generalized Linear Models and employed a model selection approach to examine the impact of local variables(fire severity(FIRE)and basal area of pioneer tree species(PIONEER))and landscape-scale variables(amount of habitat(COVER))on patterns of species richness,composition,and body size of wasps.A total of 374 individuals(29 species)were collected across all sampling sites.COVER was the main predictor of species richness,while PIONEER was the only variable that explained variation in community composition,with a negative effect on body size.Our results add evidence to the pervasive impacts of large hydroelectric dams on tropical forest biodiversity,and suggest that social wasps,among other invertebrates,can be used as bioindicators in infrastructure development projects.展开更多
The metabolic syndrome(MS), which includes obesity,dyslipidaemia, hypertension and hyperglycaemia according to the most widely accepted definitions now used, is one of the most common post-transplant complications, wi...The metabolic syndrome(MS), which includes obesity,dyslipidaemia, hypertension and hyperglycaemia according to the most widely accepted definitions now used, is one of the most common post-transplant complications, with a prevalence of 44%-58%. The MS, together with the immunosuppression, is considered the main risk factor for the development of cardiovascular disease(CVD) in transplant recipients, which in turn accounts for 19%-42% of all deaths unrelated to the graft. The presence of MS represents a relative risk for the development of CVD and death of 1.78. On the other hand, non-alcoholic fatty liver disease(NAFLD), considered as the manifestation of the MS in the liver, is now the second leading reason for liver transplantation in the United States after hepatitis C and alcohol. NAFLD has a high rate of recurrence in the liver graft and a direct relation with the worsening of other metabolic disorders, such as insulin resistance or diabetes mellitus. Consequently, it is vitally important to identify and treat as soon as possible such modifiable factors as hypertension, overweight, hyperlipidaemia or diabetes in transplanted patients to thus minimise the impact on patient survival. Additionally, steroid-free regimens are favoured, with minimal immunosuppression to limit the possible effects on the development of the MS.展开更多
INTRODUCTIONIt is axiomatic that the most effective and soundlybased plan of treatment of any disorder is one aimedat the mechanism or mechanisms responsible for itsdevelopment.This basic notion,coupled withrecent rep...INTRODUCTIONIt is axiomatic that the most effective and soundlybased plan of treatment of any disorder is one aimedat the mechanism or mechanisms responsible for itsdevelopment.This basic notion,coupled withrecent reports in which,surprisingly there is atotal lack of reference to the probable involvementof autonomic-arc-reflexes in the展开更多
Objective:To estimate to what extent the mixture of ursolic acid and oleanolic acid,in addition to the antitubercular standard regime,affects the hepatotoxicity profile.Methods:Liver injury was induced in male BALB/c ...Objective:To estimate to what extent the mixture of ursolic acid and oleanolic acid,in addition to the antitubercular standard regime,affects the hepatotoxicity profile.Methods:Liver injury was induced in male BALB/c mice by administering,per os and daily for 11 weeks,a combination of anti-Tubercular(anti-TB) agents Rifampicin(10 mg/kg),Isoniazid(10 mg/kg),and Pyrazinamide(30 mg/kg).The ursolic acid and oleanolic acid mixture at doses of 100 or 200 μg/mouse/day was subcutaneously injected throughout the entire study period(11 weeks).Biochemical and hematological analysis was supplemented by liver histological examination.Results:Animals treated with the mixture of triterpenic acids exhibited significantly decreased aspartate transaminase and alanine aminotransferase levels and amelioration of the histopathological alterations produced by the anti-TB drugs.Conclusions:The triterpene mixture is able to prevent the steatosis induced by the anti-TB drugs.展开更多
Gallbladder tuberculosis (GT) is an extremely rare disease, and very few cases have been reported in the literature. The first case of GT was described in 1870 by Gaucher. A correct preoperative diagnosis of GT is unu...Gallbladder tuberculosis (GT) is an extremely rare disease, and very few cases have been reported in the literature. The first case of GT was described in 1870 by Gaucher. A correct preoperative diagnosis of GT is unusual, and it is frequently confused with various gallbladder diseases. We present a new case of a patient who underwent surgery with the preoperative diagnosis of gallbladder cancer after a false positive positron emission tomography scan in the diagnostic work-up.展开更多
Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The ex...Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The existence of optimal controls for the systems is given. Finally, two examples are provided to show the application of our results.展开更多
The anther culture technical was applied to produce haploid lines of rice (Oryza sativa L.). The hybrids (K/ A92VM061, K/A92VM067, K/A92VM0611, K/A92VM719, K/A92VM720 and K/A92VM721) were obtained in order to generate...The anther culture technical was applied to produce haploid lines of rice (Oryza sativa L.). The hybrids (K/ A92VM061, K/A92VM067, K/A92VM0611, K/A92VM719, K/A92VM720 and K/A92VM721) were obtained in order to generate new varieties from Indica and Japonica cultivars. Morphometric parameters of the grains were evaluated by image analysis. Flours were prepared from the whole rice grains and physicochemical, thermal and rheological properties, X-ray diffraction pattern and evaluation of color using the CIELAB system were assessed. The hybrids lines showed long (061, 611, 721), medium (719 and 720) and short (067) grains. The rice samples presented lipids (2.6% - 3.2%), protein (11% - 15%), total dietary fiber (8.4% - 10.2%), total starch (65% - 74%) and apparent amylose (5% - 32%) contents. Gelatinization temperature (Tp) was found in the range of 66.1℃ - 79.4℃ with enthalpy (ΔH) value between 3.4 - 8.1 J/g. The retrogradation parameters (temperature and ΔH) were lower than those for gelatinization in all samples. The rice samples presented A-type X-ray diffraction pattern. Rice pastes showed a non-Newtonian behavior and the brightness (L*) characterize the color of the samples. Hybrid rice grains presented morphometric properties more similar to Japonica than Indica variety. Rice hybrid had higher protein content than Indica variety. Apparent amylose, viscosity and gelatinization temperature varied significantly among hybrids and varieties.展开更多
Brucella suis is responsible for swine brucellosis worldwide. Of the five different B. suis biovars （by.）, bv. 2 appears restricted to Europe where it is frequently isolated from wild boar and hares, can infect pigs...Brucella suis is responsible for swine brucellosis worldwide. Of the five different B. suis biovars （by.）, bv. 2 appears restricted to Europe where it is frequently isolated from wild boar and hares, can infect pigs and can cause human brucellosis. In this study, the differ- ential gene expression profile was characterized in spleens of Eurasian wild boar naturally infected with B. suis bv. 2. Of the 20,201 genes analyzed in the microarray, 633 and 1,373 were significantly （fold change 〉 1.8; P 〈 0.01） upregulated and downregulated, respectively, in infected wild boar. The analysis was focused on genes that were over represented after conditional test for biological process gene ontology. Upregulated genes suggested that B. suis bv. 2 infection induced cell maturation, migration and/or proliferation in infected animals. The genes downregulated in infected wild boar impaired the activity of several important cellular metabolic pathways such as metabolism, cytoskeleton organization and biogenesis, immune response and lysosomal function and vesicle-mediated transport. In addition, the response to stress, sperm fertility, muscle development and apoptosis seemed to be also impaired in infected animals. These results suggested that B. suis bv. 2 may use strategies similar to other smooth brucellae to facilitate intracellular multiplication and the development of chronic infections. To our knowledge, this is the first report of the analysis of gene expression profile in hosts infected with B. suis bv. 2, which is important to understand the molecular mechanisms at the host-pathogen interface in the main reservoir species with possible implications in the zoonotic cycle of the pathogen.展开更多
Brain size and weight vary tremendously in the animal kingdom. It has been suggested that brain structural develop- ment must evolve balanced between the advantages of dealing with greater social challenges mad the en...Brain size and weight vary tremendously in the animal kingdom. It has been suggested that brain structural develop- ment must evolve balanced between the advantages of dealing with greater social challenges mad the energetic costs of maintain- ing and developing larger brains. Here we ask if interspecific differences in cooperative behaviour （i.e. cleaning behaviour） are related to brain weight variations in four close-related species of Labrid fish： two are obligatory cleanerfish throughout their en- tire life （Labroides dimidiatus and L. bicolor）, one facultative cleaner fish Labropsis australis and one last species that never en- gage in cleaning Labrichthys unilineatus. We first search for the link between the rate of species＇ cooperation and its relative brain weight, and finally, if the degree of social complexity and cooperation are reflected in the weight of its major brain sub- structures. Overall, no differences were found in relative brain weight （in relation to body weight） across species. Fine-scale dif- ferences were solely demonstrated for the facultative cleaner L. australis, at the brainstem level. Furthermore, data visual exami- nation indicates that the average cerebellum and brainstem weights appear to be larger for L. dimidiatus. Because variation was solely found at specific brain areas （such as cerebellum and brainstem） and not for the whole brain weight values, it suggests that species social-ecological and cognitive demands may be directly contributing to a selective investment in relevant brain areas. This study provides first preliminary evidence that links potential differences in cognitive ability in cooperative behaviour to how these may mediate the evolution of brain structural development in non-mammal vertebrate groups .展开更多
Let Q be the Q-matrix of an irreducible, positive recurrent Markov process on a countable state space. We show that, under a number of conditions, the stationary distributions of the n × n north-west corner augme...Let Q be the Q-matrix of an irreducible, positive recurrent Markov process on a countable state space. We show that, under a number of conditions, the stationary distributions of the n × n north-west corner augmentations of Q converge in total variation to the stationary distribution of the process. Two conditions guaranteeing such convergence include exponential ergodicity and stochastic monotonicity of the process. The same also holds for processes dominated by a stochastically monotone Markov process. In addition, we shall show that finite perturbations of stochastically monotone processes may be viewed as being dominated by a stochastically monotone process, thus extending the scope of these results to a larger class of processes. Consequently, the augmentation method provides an attractive, intuitive method for approximating the stationary distributions of a large class of Markov processes on countably infinite state spaces from a finite amount of known information.展开更多
Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat im...Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat images and OBIA methodology. Additionally, landscape analyses using FRAGSTAT were conducted. In 2014, Sierra de Juarez–Oaxaca was covered by approximately 84% of forests, mainly pine-oak and cloud forests. After extensive deforestation until 2001, this trend was reversed and the forest cover surface area in 2014 was slightly higher than in 1979. The comparison of the landscape structure of the forested and agricultural lands suggests an increase in habitat heterogeneity. However, interspersion and juxtaposition indices, showing the patch shape by patch area and perimeter, were similar throughout the study period(1979–2014). Social and economic drivers can explain this situation: namely, community organization, forest enterprises, payment for ecosystem services programs, and changes of agricultural activity. Communities in the Sierra of Oaxaca have reforested degraded lands, created community forest enterprises, and preserved the forest under conservation schemes like those proposed by the Mexican payment for ecosystem services programs. However, their sustainable management faces internal challenges and has become highly dependent on political and institutional decisions beyond their control.展开更多
文摘Bioethics is the argumentative discipline of decisions and actions that reduce conflicts of interest,dilemmas,or asymmetries between the parties involved in biomedical research.The objective of this work was to review and compare the dimensions used by bioethics in the communicative management of the pandemic,namely:risk,vulnerability,resilience,and stigma.A documentary,exploratory,transversal,and retrospective work was carried out with a sample of sources indexed in international repositories,considering the search by keywords and the publication period from 2020 to 2024.The results demonstrate the prevalence of supply,contagion,symptoms,and help against COVID-19.
基金supported by the EU under grant 824093(STRONG2020)spanish MICINN under PID2019-108655GBI00/AEI/10.13039/501100011033,PID2019-106080GB-C21 and PRX23/00225(estancias en el extranjero)Univ.Complutense de Madrid under research group 910309 and the IPARCOS institute。
文摘We extend a well-known mass-gap equation for pure gluodynamics in global colour models(formulated in equal-time quantization in Coulomb gauge)to one in which gluons are split into two sets,each exhibiting different masses.If the theory is SU(N)×SU(M)with gluons in both groups having identical couplings(as suggested by Grand Unification arguments at large scales)it is immediate to see that different masses are generated for each subgroup.This global symmetry is not broken,but the split masses erase accidental symmetries that might be present due to the two couplings being the same at a large scale,such as SU(N×M)or similar.We also numerically explore a couple of low-dimensional examples of simple Lie groups,but in spite of the system of equations having a form that would seem to allow spontaneous symmetry breaking,it is not triggered for these groups whose algebra has no ideal,and the dispersion relations for the various gluons converge to the same form.
基金supported by the National Geographic Society through an early career grant to A.Rico (EC-59809C-19)Support Programme-PlanGenT (CIDEGENT/2020/043)of the Generalitat ValencianaR.Oliveira acknowledges"Fundacao de Amparo a Pesquisa do Estado de Sao Paulo"-FAPESP (Project 2018/03108-0).
文摘Fish constitutes the main protein source for the Amazonian population.However,the impact of different anthropogenic activities on trace element and metal accumulation in fish and their risks for human health at a regional scale remain largely unexplored.Here we assessed exposure levels of 10 trace elements andmetals(Cr,Mn,Fe,Ni,Cu,Zn,As,Cd,Pb,and Hg)in 56 samples belonging to 11 different species of fish from the Brazilian Amazon.We studied the relationship between exposure levels,fish origin,and fish feeding habits,and assessed toxicological and carcinogenic risks for the Amazonian population.No significant correlation was found between sampling site and exposure levels to the studied elements,but a significant difference was found between the accumulation of some metals and the position of the fish species in the food chain.The concentrations of Cr and Hg in fish flesh were found to exceed the Brazilian limits for human consumption.This study shows that current fish consumption patterns can lead to estimated daily intakes of Hg,As and Cr that exceed the oral reference dose,thus posing a toxicological concern.Furthermore,carcinogenic risks may be expected due to the continued exposure to Cr and As.The results of this study show that the consumption of wild caught fish in the Amazon region should be controlled.Moreover,continued monitoring of trace element and metal contamination in fish and on the health of the Amazonian population is recommended,particularly for riverine and indigenous communities.
基金supported by a doctoral grant from the National Scientific and Technical Research Council(Consejo Nacional de Investigaciones Científicas y T ecnicas,CONICET)the National Institute of Agricultural Technology(INTA)+1 种基金by projects funded by INTA(CP_2019–2023 I-114,I-127,I-090/2023–2025 I-111,I-87)Agencia Nacional de Promocio n Científica y T ecnica(PICT 2017N?2523)。
文摘Multiparent advanced generation inter-cross(MAGIC)populations improve the accuracy of quantitative trait loci mapping compared to biparental populations by increasing diversity and reducing linkage disequilibrium between variants.Here we describe the development of two MAGIC populations derived from a cross of 11 founder lines from the INTA(National Institute for Agricultural Technology in Argentina)sunflower breeding program.The founder lines are fertility maintainer inbred lines that exhibit genetic diversity in several traits,including flowering cycle,plant architecture,disease resistance,oil content and oil quality.The crossing scheme applied follows the design of two-way,four-way and eight-way crosses with a modification to increase the number of recombinations and shorten the linkage disequilibrium.Phenotyping a subset of F_(2)families and F_5 lines for different traits shows an increase in the diversity of the analyzed traits compared to the parental lines.In addition,we identified lines with transgressive segregation for Sunflower Verticillium Wilt resistance.These results confirm that the MAGIC populations will serve as unique genetic and genomic resources to better characterize the genetics of complex traits and identify potentially superior alleles for sunflower breeding.It will also enrich the gene pool of fertility maintainers(A/B line)of the sunflower germplasm and facilitate the introduction of new breeding methods to select female parents for use in AxR combinations to obtain superior sunflower hybrids.
基金funded by the Spanish Ministry of Economy and Competitiveness,No.PID(2019)-106498GB-100 (to MVS)by the Instituto de Salud CarlosⅢ,Fondo Europeo de Desarrollo Regional"Una manera de hacer Europa",No.PI19/00071 (to MAB)+2 种基金the RETICS subprograms of Spanish Networks OftoRed,Nos.RD16/0008/0026 (to DGB) and RD16/0008/0016 (to DGB)RICORS Terav,No.RD16/0011/0001 (to DGB)from Instituto de Salud CarlosⅢby the Fundacion Seneca,Agencia de Cienciay Tecnologia Región de Murcia,No.19881/GERM/15 (all to MVS)
文摘Advanced mesenchymal stromal cell-based therapies for neurodegenerative diseases are widely investigated in preclinical models.Mesenchymal stromal cells are well positioned as therapeutics because they address the underlying mechanisms of neurodegeneration,namely trophic factor deprivation and neuroinflammation.Most studies have focused on the beneficial effects of mesenchymal stromal cell transplantation on neuronal survival or functional improvement.However,little attention has been paid to the interaction between mesenchymal stromal cells and the host immune system due to the immunomodulatory properties of mesenchymal stromal cells and the long-held belief of the immunoprivileged status of the central nervous system.Here,we review the crosstalk between mesenchymal stromal cells and the immune system in general and in the context of the central nervous system,focusing on recent work in the retina and the importance of the type of transplantation.
基金supported partially by DGAPA/PAPIIT UNAM grant 220321 to LMOO.JAV received support from a DGAPA/PAPIIT UNAM grant(IA206523).
文摘Protected areas(PA)have proven to be one of the best ways to conserve biodiversity against environmental changes.Amphibians are considered the most threatened group,with habitat loss due to deforestation identified as their major threat.Here,we assessed for each PA of the American continent:1)amphibian’s occurrence(Global Biodiversity Information Facility(GBIF)vs.International Union for Conservation of Nature(IUCN)data);2)temperature velocity and estimated the climate residence time,and using the latest models of the land future use;3)we estimated the changes of natural vs.modified cover in three future scenarios.Amphibian occurrence showed differences between databases,while GBIF data shows that 52%of the amphibian species occurring in the continent are in PA,based on IUCN data,85%are protected.Results from climate change show a low pace of climate velocity during the last century that is maintained in the green scenario(SSP126).However,change in temperature increases in rate in the rest of the scenarios,with scenario SSP58 showing the highest velocity of temperature change.Future estimates of residence times in PA show that lower levels as emission scenarios tend to be higher.These results are worrisome since climate lag,specifically temperature increase over the PA will probably affect amphibian communities as shown in previous studies.Changes in climate patterns have a direct—mostly negative—impact on amphibians’ability to disperse and reproduce.The results of land use change were unexpected,since the categories showed minimal changes.However,the data on urbanization changes do not seem to be reflecting the trends of other databases,which may be causing artifacts in the comparisons in the future models of land use.Further research will be necessary to evaluate the extent of similarities and differences in future projections of land use including urbanization and human population between different databases.
基金Supported by the Research Nucleus in LimnologyIchthyology and Aquaculture (NUPELIA) for logistic support+4 种基金the Laboratory of Energetic Ecology and the Long-term Ecological Research Program (PELD/CNPq)Site 6-PIAP (upper ParanáRiver floodplain)PROEXUEMand Fundação Araucária for the scholarship
文摘Particulate organic matter(POM)is an important energy source for aquatic consumers,understanding its origin and composition is essential for understanding the energetic dynamics of aquatic environments.The aim of this study was to analyze the relationship between POM and phytoplankton(isotopic values and chlorophyll concentration)and abiotic variables during dry and rainy seasons.Sampling was conducted in rivers and lagoons in the floodplain of the Upper ParanáRiver.We found a greater difference in ^(δ13)C values of POM between sampling points than between seasons,indicating that the composition of regional sources influences the composition of POM more than dry and rainy seasons.In addition,the concentration of chlorophyll during the dry season was positively correlated with ^(δ13)C values during that rainy period.Additionally,we found a relationship between factors limiting the growth of phytoplankton and ^(δ13)C values of POM,such as phosphate ions,indicating that variables that regulate phytoplankton growth tend to influence the composition of POM in river floodplains.Therefore,maintaining the variables that regulate the phytoplankton community is of fundamental importance for the composition of POM,an important energy source in aquatic environments.
文摘Because of environmental constraints,beef cattle was for more than a century the only viable farming option in the extensive semiarid and subhumid lands of Argentina and the main source of nutrients for humans as well.However,a growing concern and criticism have risen today about its possible negative impact on the climate and the environment.These worries tend to affect current public opinions,national policies,and international trade.Based on 40 beef cattle farms scattered across different semiarid and subhumid regions of Argentina,here we evaluated the impact of extensive cattle production on carbon,water,and nutrient pollution.Life-Cycle Assessment(LCA)and Land-Based Assessment(LBA)were the two approaches we used here to compare the environmental impact of beef production.While the environmental footprint(EF)resulting from LCA expresses the impact per unit of food,the environmental balance(EB),derived from LBA,aims at quantifying the impact per unit of land.As such,the EB considers both negative and positive impacts on the farm as an integrated system.Following standardized procedures,we evaluated EF and EB up to the farm gate,leaving aside delocalized post-farm impacts such as those of processing,packaging,and transportation that occur beyond the farm gate.In agreement with previous evidence,our results show that the EF tends to decrease as per-head production increases.Correlation coefficients and statistical significance were the following for carbon(R=−0.574;p<0.01),water(R=−0.561;p<0.01),and N(R=−0.704;p<0.01)and Phosphorus(P)pollution(R=−0.802;p<0.01)footprints.On the contrary,the EB seems to be highly sensitive,and as per-hectare beef production increases.Correlations were the following for carbon emissions(CE:R=0.955;p<0.01),water consumption(WC:R=0.822;p<0.01),nitrogen excretion(NE:R=0.948;p<0.01)and phosphorus excretion(PE:R=0.945;p<0.01).What our results suggest is that the notion of EF is useful to evaluate the environmental impact in intensive beef production systems,and the EB is suitable to assess the impact of the extensive ones.In practice,both approaches provide different perspectives on the environmental-impact problem and they should be complementary used.We concluded that the methodological rigidity of EF does not allow proper discrimination among farms in the extensive systems.On the contrary,the EB approach tended to be highly sensitive to detecting differences between individual farms and farmers,thus allowing the identification of successful options for extensive beef production in terms of public image,policy-making,and commercial opportunities.
基金partially supported by the Namibia Students Financial Assistance Fund(NSFAF)Kreditanstalt für Wiederaufbau(KfW)-University of Namibia(UNAM,BMZ Ref.2015.67.015)+2 种基金funded by the project TROPIBIO NORTE-01-0145-FEDER-000046supported by Norte Portugal Regional Operational Programme(NORTE2020)developed in the framework of the“Twin Lab CIBIO/UNAM”(UNESCO Chair Life on Land)。
文摘As the sole obligate symbiotic birds in Africa,oxpeckers offer a unique model for studying symbiotic relationships.Due to the multitrophic level they occupy and the context dependent foraging behavior they exhibit,the type of symbiotic relationship can be variable.In addition to providing a cleaning service to the host by removing ticks,oxpeckers frequently feed on blood,mucus,and saliva,inflicting potential damage on the host.Here,we used DNA metabarcoding on faecal samples to analyze the taxonomic composition of the trophic interactions of the Yellow-billed Oxpecker(Buphagus africanus)and Red-billed Oxpecker(B.erythrorhynchus)in northeastern Namibia.In contrast to conventional methods,DNA metabarcoding allows for a detailed identification of dietary resources encompassing both mammal hosts and consumed arthropods within the same samples.With this information,we examined differences in the diet composition between oxpecker species and localities,as well as the co-occurrence between host and arthropod species.Our findings revealed that oxpeckers predominantly source their diet from mammals,ticks,and flies;however,ticks and flies rarely co-occur in the diet of an individual.We observed variability among individuals in their feeding ecology,which is strongly correlated with locality and,to a lesser extent,with the mammal host.We noted a high degree of mobility between hosts within relatively short periods,with 32%of the samples showing traces of at least two mammal hosts.This study illustrates the dynamic foraging behavior of these specialized symbiotic birds,shedding light on their potential role in pest control services and disease transmission.
基金supported by a NERC grant to C.A.P.(NE/J01401X/1)a Science Without Borders postdoctoral fellowship awarded to D.S.(CNPq grant 246975/2012-1)+1 种基金M.B.received a productivity grant from CNPq(304189/2022-7)supported by the inaugural Frontiers Planet Prize。
文摘Hydropower development has become an important driver of habitat loss and fragmentation across lowland tropical forests.Despite ample evidence on the detrimental effects of insular habitat fragmentation on biodiversity,invertebrate taxa,that may be critical to ecosystem functioning,have been overlooked.We assessed the assemblage-level responses of social wasps to forest insularization induced by the Balbina Hydroelectric Dam in Central Brazilian Amazonia.Employing Malaise trapping,we captured wasps on 27 forest islands and three continuous forests.We constructed Generalized Linear Models and employed a model selection approach to examine the impact of local variables(fire severity(FIRE)and basal area of pioneer tree species(PIONEER))and landscape-scale variables(amount of habitat(COVER))on patterns of species richness,composition,and body size of wasps.A total of 374 individuals(29 species)were collected across all sampling sites.COVER was the main predictor of species richness,while PIONEER was the only variable that explained variation in community composition,with a negative effect on body size.Our results add evidence to the pervasive impacts of large hydroelectric dams on tropical forest biodiversity,and suggest that social wasps,among other invertebrates,can be used as bioindicators in infrastructure development projects.
文摘The metabolic syndrome(MS), which includes obesity,dyslipidaemia, hypertension and hyperglycaemia according to the most widely accepted definitions now used, is one of the most common post-transplant complications, with a prevalence of 44%-58%. The MS, together with the immunosuppression, is considered the main risk factor for the development of cardiovascular disease(CVD) in transplant recipients, which in turn accounts for 19%-42% of all deaths unrelated to the graft. The presence of MS represents a relative risk for the development of CVD and death of 1.78. On the other hand, non-alcoholic fatty liver disease(NAFLD), considered as the manifestation of the MS in the liver, is now the second leading reason for liver transplantation in the United States after hepatitis C and alcohol. NAFLD has a high rate of recurrence in the liver graft and a direct relation with the worsening of other metabolic disorders, such as insulin resistance or diabetes mellitus. Consequently, it is vitally important to identify and treat as soon as possible such modifiable factors as hypertension, overweight, hyperlipidaemia or diabetes in transplanted patients to thus minimise the impact on patient survival. Additionally, steroid-free regimens are favoured, with minimal immunosuppression to limit the possible effects on the development of the MS.
文摘INTRODUCTIONIt is axiomatic that the most effective and soundlybased plan of treatment of any disorder is one aimedat the mechanism or mechanisms responsible for itsdevelopment.This basic notion,coupled withrecent reports in which,surprisingly there is atotal lack of reference to the probable involvementof autonomic-arc-reflexes in the
基金partly supported by Grant from the Instituto Mexicano del Seguro Social (NO.FIS/IMSS/PROT/G12/1126FIS/IMSS/PROT/G14/1341)
文摘Objective:To estimate to what extent the mixture of ursolic acid and oleanolic acid,in addition to the antitubercular standard regime,affects the hepatotoxicity profile.Methods:Liver injury was induced in male BALB/c mice by administering,per os and daily for 11 weeks,a combination of anti-Tubercular(anti-TB) agents Rifampicin(10 mg/kg),Isoniazid(10 mg/kg),and Pyrazinamide(30 mg/kg).The ursolic acid and oleanolic acid mixture at doses of 100 or 200 μg/mouse/day was subcutaneously injected throughout the entire study period(11 weeks).Biochemical and hematological analysis was supplemented by liver histological examination.Results:Animals treated with the mixture of triterpenic acids exhibited significantly decreased aspartate transaminase and alanine aminotransferase levels and amelioration of the histopathological alterations produced by the anti-TB drugs.Conclusions:The triterpene mixture is able to prevent the steatosis induced by the anti-TB drugs.
文摘Gallbladder tuberculosis (GT) is an extremely rare disease, and very few cases have been reported in the literature. The first case of GT was described in 1870 by Gaucher. A correct preoperative diagnosis of GT is unusual, and it is frequently confused with various gallbladder diseases. We present a new case of a patient who underwent surgery with the preoperative diagnosis of gallbladder cancer after a false positive positron emission tomography scan in the diagnostic work-up.
基金supported by the Science and Technology Planning Project(2014JQ1041)of Shaanxi Provincethe Scientic Research Program Funded by Shaanxi Provincial Education Department(14JK1300)+1 种基金the Research Fund for the Doctoral Program(BS1342)of Xi’an Polytechnic Universitysupported by Ministerio de Economíay Competitividad and EC fund FEDER,Project no.MTM2010-15314,Spain
文摘Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The existence of optimal controls for the systems is given. Finally, two examples are provided to show the application of our results.
文摘The anther culture technical was applied to produce haploid lines of rice (Oryza sativa L.). The hybrids (K/ A92VM061, K/A92VM067, K/A92VM0611, K/A92VM719, K/A92VM720 and K/A92VM721) were obtained in order to generate new varieties from Indica and Japonica cultivars. Morphometric parameters of the grains were evaluated by image analysis. Flours were prepared from the whole rice grains and physicochemical, thermal and rheological properties, X-ray diffraction pattern and evaluation of color using the CIELAB system were assessed. The hybrids lines showed long (061, 611, 721), medium (719 and 720) and short (067) grains. The rice samples presented lipids (2.6% - 3.2%), protein (11% - 15%), total dietary fiber (8.4% - 10.2%), total starch (65% - 74%) and apparent amylose (5% - 32%) contents. Gelatinization temperature (Tp) was found in the range of 66.1℃ - 79.4℃ with enthalpy (ΔH) value between 3.4 - 8.1 J/g. The retrogradation parameters (temperature and ΔH) were lower than those for gelatinization in all samples. The rice samples presented A-type X-ray diffraction pattern. Rice pastes showed a non-Newtonian behavior and the brightness (L*) characterize the color of the samples. Hybrid rice grains presented morphometric properties more similar to Japonica than Indica variety. Rice hybrid had higher protein content than Indica variety. Apparent amylose, viscosity and gelatinization temperature varied significantly among hybrids and varieties.
基金supported by the Grupo Santander and Fundación Marcelino Botín,Spain (Project Control of Tu-berculosis in Wildlife), Ministerio de Educación y Ciencia (MECProject AGL2005-07401)FEDER,Spain. R.C. Galindo was funded by MEC,Spain
文摘Brucella suis is responsible for swine brucellosis worldwide. Of the five different B. suis biovars （by.）, bv. 2 appears restricted to Europe where it is frequently isolated from wild boar and hares, can infect pigs and can cause human brucellosis. In this study, the differ- ential gene expression profile was characterized in spleens of Eurasian wild boar naturally infected with B. suis bv. 2. Of the 20,201 genes analyzed in the microarray, 633 and 1,373 were significantly （fold change 〉 1.8; P 〈 0.01） upregulated and downregulated, respectively, in infected wild boar. The analysis was focused on genes that were over represented after conditional test for biological process gene ontology. Upregulated genes suggested that B. suis bv. 2 infection induced cell maturation, migration and/or proliferation in infected animals. The genes downregulated in infected wild boar impaired the activity of several important cellular metabolic pathways such as metabolism, cytoskeleton organization and biogenesis, immune response and lysosomal function and vesicle-mediated transport. In addition, the response to stress, sperm fertility, muscle development and apoptosis seemed to be also impaired in infected animals. These results suggested that B. suis bv. 2 may use strategies similar to other smooth brucellae to facilitate intracellular multiplication and the development of chronic infections. To our knowledge, this is the first report of the analysis of gene expression profile in hosts infected with B. suis bv. 2, which is important to understand the molecular mechanisms at the host-pathogen interface in the main reservoir species with possible implications in the zoonotic cycle of the pathogen.
文摘Brain size and weight vary tremendously in the animal kingdom. It has been suggested that brain structural develop- ment must evolve balanced between the advantages of dealing with greater social challenges mad the energetic costs of maintain- ing and developing larger brains. Here we ask if interspecific differences in cooperative behaviour （i.e. cleaning behaviour） are related to brain weight variations in four close-related species of Labrid fish： two are obligatory cleanerfish throughout their en- tire life （Labroides dimidiatus and L. bicolor）, one facultative cleaner fish Labropsis australis and one last species that never en- gage in cleaning Labrichthys unilineatus. We first search for the link between the rate of species＇ cooperation and its relative brain weight, and finally, if the degree of social complexity and cooperation are reflected in the weight of its major brain sub- structures. Overall, no differences were found in relative brain weight （in relation to body weight） across species. Fine-scale dif- ferences were solely demonstrated for the facultative cleaner L. australis, at the brainstem level. Furthermore, data visual exami- nation indicates that the average cerebellum and brainstem weights appear to be larger for L. dimidiatus. Because variation was solely found at specific brain areas （such as cerebellum and brainstem） and not for the whole brain weight values, it suggests that species social-ecological and cognitive demands may be directly contributing to a selective investment in relevant brain areas. This study provides first preliminary evidence that links potential differences in cognitive ability in cooperative behaviour to how these may mediate the evolution of brain structural development in non-mammal vertebrate groups .
文摘Let Q be the Q-matrix of an irreducible, positive recurrent Markov process on a countable state space. We show that, under a number of conditions, the stationary distributions of the n × n north-west corner augmentations of Q converge in total variation to the stationary distribution of the process. Two conditions guaranteeing such convergence include exponential ergodicity and stochastic monotonicity of the process. The same also holds for processes dominated by a stochastically monotone Markov process. In addition, we shall show that finite perturbations of stochastically monotone processes may be viewed as being dominated by a stochastically monotone process, thus extending the scope of these results to a larger class of processes. Consequently, the augmentation method provides an attractive, intuitive method for approximating the stationary distributions of a large class of Markov processes on countably infinite state spaces from a finite amount of known information.
基金supported by the COMET-LA project(FP7-Environment-ENV.2011.4.2.3-1-282845)of the European Community
文摘Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat images and OBIA methodology. Additionally, landscape analyses using FRAGSTAT were conducted. In 2014, Sierra de Juarez–Oaxaca was covered by approximately 84% of forests, mainly pine-oak and cloud forests. After extensive deforestation until 2001, this trend was reversed and the forest cover surface area in 2014 was slightly higher than in 1979. The comparison of the landscape structure of the forested and agricultural lands suggests an increase in habitat heterogeneity. However, interspersion and juxtaposition indices, showing the patch shape by patch area and perimeter, were similar throughout the study period(1979–2014). Social and economic drivers can explain this situation: namely, community organization, forest enterprises, payment for ecosystem services programs, and changes of agricultural activity. Communities in the Sierra of Oaxaca have reforested degraded lands, created community forest enterprises, and preserved the forest under conservation schemes like those proposed by the Mexican payment for ecosystem services programs. However, their sustainable management faces internal challenges and has become highly dependent on political and institutional decisions beyond their control.
