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1.
Trends Genet ; 39(7): 545-559, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36801111

RESUMO

The availability of public genomic resources can greatly assist biodiversity assessment, conservation, and restoration efforts by providing evidence for scientifically informed management decisions. Here we survey the main approaches and applications in biodiversity and conservation genomics, considering practical factors, such as cost, time, prerequisite skills, and current shortcomings of applications. Most approaches perform best in combination with reference genomes from the target species or closely related species. We review case studies to illustrate how reference genomes can facilitate biodiversity research and conservation across the tree of life. We conclude that the time is ripe to view reference genomes as fundamental resources and to integrate their use as a best practice in conservation genomics.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Genômica , Genoma
2.
Phys Chem Chem Phys ; 26(22): 15916-15926, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38805377

RESUMO

Nanoporous carbon-based membranes have garnered significant interest in gas separation processes owing to their distinct structure and properties. We have investigated the permeation and separation of the mixture of CO2 and CH4 gases through membranes formed by thin layers of porous graphdiyne (GDY) and boron graphdiyne (BGDY) using Density Functional Theory. The main goal is to investigate the effect of the pore size. The interaction of CO2 and CH4 with GDY and BGDY is weak, and this guarantees that those molecules will not be chemically trapped on the surface of the porous membranes. The permeation and separation of CO2 and CH4 through the membranes are significantly influenced by the size of the pores in the layers. The size of the hexagonal pores in BGDY is large in comparison to the size of the two molecules, and the passing of these molecules through the pores is easy because there is no barrier. Then, BGDY is not able to separate CO2 and CH4. In sharp contrast, the size of the triangular pores in GDY is smaller, comparable to the diameter of the two molecules, and this raises an activation barrier for the crossing of the molecules. The height of the barrier for CO2 is one half of that for CH4, the reason being that CO2 is a linear molecule which adopts an orientation perpendicular to the GDY layer to cross the pores, while CH4 has a spherical-like shape, and cannot profit from a favorable orientation. The calculated permeances favor the passing of CO2 through the GDY membrane, and the calculated selectivity for CO2/CH4 mixtures is large. This makes GDY a very promising membrane material for the purification of commercial gases and for the capture of the CO2 component in those gases.

3.
Environ Microbiol ; 25(12): 2698-2718, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37515381

RESUMO

Plastic pollution is an increasing worldwide problem urgently requiring a solution. While recycling rates are increasing globally, only 9% of all plastic waste has been recycled, and with the cost and limited downstream uses of recycled plastic, an alternative is needed. Here, we found that expanded polystyrene (EPS) promoted high levels of bacterial biofilm formation and sought out environmental EPS waste to characterize these native communities. We demonstrated that the EPS attached communities had limited plastic degrading activity. We then performed a long-term enrichment experiment where we placed a robust selection pressure on these communities by limiting carbon availability such that the waste plastic was the only carbon source. Seven of the resulting enriched bacterial communities had increased plastic degrading activity compared to the starting bacterial communities. Pseudomonas stutzeri was predominantly identified in six of the seven enriched communities as the strongest polyester degrader. Sequencing of one isolate of P. stutzeri revealed two putative polyesterases and one putative MHETase. This indicates that waste plastic-associated biofilms are a source for bacteria that have plastic-degrading potential, and that this potential can be unlocked through selective pressure and further in vitro enrichment experiments, resulting in biodegradative communities that are better than nature.


Assuntos
Bactérias , Poliésteres , Bactérias/genética , Poliestirenos , Biofilmes , Carbono
4.
Environ Res ; 219: 115118, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36566961

RESUMO

OBJECTIVE: Smoke-free policies are effective in preventing secondhand smoke (SHS) exposure, but their adoption at home remains largely voluntary. This study aimed to quantify SHS exposure in homes with residents who smoke in Europe according to households' characteristics, tobacco consumption habits, and national contextual factors. METHODS: Cross-sectional study (March 2017-September 2018) based on measurements of air nicotine inside 162 homes with residents who smoke from nine European countries. We installed passive samplers for seven consecutive days to monitor nicotine concentrations. Through self-administered questionnaires, we collected sociodemographic information and the number of individuals who smoke, smoking rules, frequency, location, and quantity of tobacco use in households. Country-level factors included the overall score in the Tobacco Control Scale 2016, the smoking prevalence, and self-reported SHS exposure prevalence. Nicotine concentrations were analyzed as continuous and dichotomous variables, categorized based on the limit of quantification of 0.02 µg/m3. RESULTS: Overall, median nicotine concentration was 0.85 µg/m3 (interquartile range (IQR):0.15-4.42), and there was nicotine presence in 93% of homes. Participants reported that smoking was not permitted in approximately 20% of households, 40% had two or more residents who smoked, and in 79% residents had smoked inside during the week of sampling. We found higher nicotine concentrations in homes: with smell of tobacco smoke inside (1.45 µg/m3 IQR: 0.32-6.34), where smoking was allowed (1.60 µg/m3 IQR: 0.68-7.63), with two or more residents who smoked (2.42 µg/m3 IQR: 0.58-11.0), with more than 40 cigarettes smoked (2.92 µg/m3 IQR: 0.97-10.61), and where two or more residents smoked inside (4.02 µg/m3 IQR: 1.58-11.74). Household nicotine concentrations were significantly higher in countries with higher national smoking prevalence and self-reported SHS exposure prevalence (p < 0.05). CONCLUSIONS: SHS concentrations in homes with individuals who smoke were approximately twenty times higher in homes that allowed smoking compared to those reporting smoke-free household rules. Evidence-based interventions promoting smoke-free homes should be implemented in combination with strengthening other MPOWER measures.


Assuntos
Poluição por Fumaça de Tabaco , Humanos , Poluição por Fumaça de Tabaco/análise , Nicotina/análise , Estudos Transversais , Europa (Continente) , Fumar
5.
Tob Control ; 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37402576

RESUMO

BACKGROUND: We aim to assess the effect of a smoke-free beaches (SFB) intervention in Barcelona on smoking during the 2021 bathing season. METHODS: Quasi-experimental pre-post design (pre-intervention period: 15-28 May; post-intervention period: 29 May-12 September). Based on users' profiles and location, four beaches were assigned to the intervention group (IG) and five to the comparison group (CG). The intervention involved: a mayoral decree (29 May), a communication campaign and beach on-site information. We established two 3 m × 3 m transects per beach from the coastline to the promenade. Trained teams collected smoking-related information in the transects through observations and surveys to beach users. Outcomes are as follows: percentage of people reporting witnessing smoking behaviours the last fortnight and percentage of people observed smoking. We calculated and compared prevalence ratios (PRs) with adjusted Poisson regressions. RESULTS: 3751 interviews (1721 IG; 2030 CG) and 1108 observations (498 IG, 610 CG) were carried out. SFB were associated with a significant reduction in the percentage of people reporting witnessing smoking (IG (pre: 87.2%; post: 49.7%); CG (pre: 86.2%; post: 74.1%); PR (95% CI): 0.7 (0.6 to 0.8)); and in the users observed smoking in the beach (IG (pre: 3.8%; post: 3.0%); CG (pre: 2.3%; post: 9.9%); PR (95% CI): 0.3 (0.3 to 0.4)). Satisfaction scores were 8.3 (IG) and 8.1 (CG) out of 10. CONCLUSION: An SFB intervention is an effective and well-accepted measure to reduce smoking and smokers' visibility. Smoke-free measures should be extended to beaches and other non-regulated outdoor areas.

6.
J Pediatr ; 249: 50-58.e2, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35709957

RESUMO

OBJECTIVE: To characterize the longitudinal natural history of disease progression in pediatric subjects affected with mucopolysaccharidosis (MPS) IIIB. STUDY DESIGN: Sixty-five children with a confirmed diagnosis of MPS IIIB were enrolled into 1 of 2 natural history studies and followed for up to 4 years. Cognitive and adaptive behavior functions were analyzed in all subjects, and volumetric magnetic resonance imaging analysis of liver, spleen, and brain, as well as levels of heparan sulfate (HS) and heparan sulfate nonreducing ends (HS-NRE), were measured in a subset of subjects. RESULTS: The majority of subjects with MPS IIIB achieved an apex on both cognition and adaptive behavior age equivalent scales between age 3 and 6 years. Development quotients for both cognition and adaptive behavior follow a linear trajectory by which subjects reach a nadir with a score <25 for an age equivalent of 24 months by age 8 years on average and by 13.5 years at the latest. All tested subjects (n = 22) had HS and HS-NRE levels above the normal range in cerebrospinal fluid and plasma, along with signs of hepatomegaly. Subjects lost an average of 26 mL of brain volume (-2.7%) over 48 weeks, owing entirely to a loss of cortical gray matter (32 mL; -6.5%). CONCLUSIONS: MPS IIIB exists along a continuum based on cognitive decline and cortical gray matter atrophy. Although a few individuals with MPS IIIB have an attenuated phenotype, the majority follow predicted trajectories for both cognition and adaptive behavior. TRIAL REGISTRATION: ClinicalTrials.gov identifiers NCT02493998, NCT03227042, and NCT02754076.


Assuntos
Mucopolissacaridose III , Atrofia/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Cinzenta , Heparitina Sulfato , Humanos , Imageamento por Ressonância Magnética , Mucopolissacaridose III/diagnóstico
7.
Phys Chem Chem Phys ; 24(5): 2729-2751, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35077528

RESUMO

Palladium is a late transition metal element in the 4d row of the periodic table. Palladium nanoparticles show efficient catalytic activity and selectivity in a number of chemical reactions. In this paper, we review the structural and electronic properties of palladium nanoclusters, both isolated and deposited on the surface of different substrates. Careful experiments and extensive calculations have been performed for small Pd clusters which provide ample information on their properties. Work on large Pd clusters is less abundant and more difficult to perform and interpret. Cluster deposition is a method to modify material surfaces for different applications, and we report the known results for the deposition of Pd clusters on the surfaces of a number of interesting substrates: carbonaceous substrates like graphene and some layered novel materials related to graphene, metal oxide substrates, silicon and silicon-related substrates and metallic alloy substrates. Emphasis is placed on revealing how the structural, electronic and magnetic properties change when the clusters are deposited on the substrate surfaces. Some examples of chemical reactions catalyzed by supported Pd clusters and nanoparticles are reported. An issue discussed in detail is the influence of Pd on the storage of hydrogen in porous materials. Experimental work shows that the amount of stored hydrogen increases when the absorbing material is doped with Pd atoms, clusters and nanoparticles, and a spillover mechanism from the metal particle to the substrate is usually accepted as the explanation. To shed light on this issue, a critical analysis based on density functional simulations of the mechanisms of hydrogen spillover in perfect and defective graphene doped with palladium clusters is presented.

8.
Environ Res ; 195: 110806, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33515582

RESUMO

INTRODUCTION: Secondhand smoke (SHS) causes morbidity and mortality among non-smokers. OBJECTIVES: To investigate SHS presence in outdoor areas from 12 European countries and its association with country-level characteristics. METHODS: Cross-sectional study performed in 2017-2018 within the TackSHS project. We conducted a face-to-face survey on a representative sample of the population aged 15 years and older from 12 European countries: Bulgaria, England, France, Germany, Greece, Ireland, Italy, Latvia, Poland, Portugal, Romania, and Spain. Out of 11,902 participants, 8,562 were non-smokers. SHS presence was assessed in selected outdoor areas and defined as respondents viewing someone smoking the last time they visited each setting within the last 6 months. A ranking score for outdoor SHS presence was assigned to each country based on the SHS presence in each setting. We used Spearman's correlation (r) and the Chi-squared tests to assess the relationship between SHS presence and country-level characteristics. RESULTS: Except for children's playgrounds (39.5%; 95% confidence interval, CI: 37.6%-41.3%), more than half of non-smokers reported SHS presence in outdoor areas: schools (52.0%; 95%CI: 50.2%-53.7%), stadia (57.4%; 95%CI: 55.4%-59.4%), parks (67.3%; 95%CI: 66.0%-68.5%), hospitals (67.3%; 95%CI: 65.8%-68.7%), public transport stops (69.9%; 95%CI: 68.6%-71.2%), bar/restaurant terraces (71.4%; 95%CI: 70.2%-72.6%), and beaches (72.8%; 95%CI: 71.4%-74.1%). Residents in Latvia showed the highest overall outdoor SHS presence rank, followed by Greece, and Portugal. Outdoor SHS presence was directly correlated to the country's smoking prevalence (r = 0.64), and inversely correlated to the Tobacco Control Scale 2016 overall score (r = -0.62), the socio-demographic index 2017 (r = -0.56), and Gross Domestic Product per capita 2018 (r = -0.47) (p < 0.001). CONCLUSIONS: SHS presence is high in most outdoor areas in Europe, especially in countries with higher smoking prevalence and lower tobacco control performance. To address outdoor SHS exposure, our findings require considering smoking bans along with other strategies to reduce smoking prevalence.


Assuntos
Poluição por Fumaça de Tabaco , Adolescente , Bulgária , Criança , Estudos Transversais , Inglaterra , Europa (Continente) , França , Alemanha , Grécia , Humanos , Irlanda , Itália , Polônia , Portugal , Romênia , Espanha , Poluição por Fumaça de Tabaco/análise
9.
Environ Res ; 193: 110571, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33278471

RESUMO

Exposure to secondhand aerosol from electronic cigarettes (e-cigarettes) may pose harms to bystanders, but they are used in many indoor settings. Less evidence exists on e-cigarette use in outdoor settings. This study aims to assess the use of e-cigarettes in outdoor settings in Europe. A cross-sectional study was conducted at the entrances of primary schools (N = 200), children's playgrounds (N = 200), and outdoor hospitality venues (N = 220) during 2017-2018 in major cities of 11 European countries. We performed 30-min observations and recorded e-cigarette use at three-time points: at 0 min, 15 min, and 30 min. We described the number and proportion of settings with e-cigarette use observed at any of the three-time points according to country and other contextual variables. Results showed that there were 22 (11.0%) school entrances, eight (4.0%) playgrounds, and 47 (21.3%) outdoor hospitality venues where e-cigarette use was observed at any time point. School entrances and outdoor hospitality venues with observed e-cigarette use were more frequently found in countries with a higher prevalence (≥1.4%) of e-cigarette use (school entrances: 18.0% vs. 4.0%; p = 0.002, outdoor hospitality venues: 26.7% vs. 15.0%, p = 0.036). In conclusion, the outdoor setting with the highest visibility of e-cigarette use was outdoor areas of hospitality venues. Although still limited, e-cigarettes were also used in outdoor settings frequented by children. Governments should consider measures to restrict e-cigarette use outdoors to protect the health of bystanders, particularly in areas where children may be present.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Poluição por Fumaça de Tabaco , Vaping , Criança , Cidades , Estudos Transversais , Europa (Continente)/epidemiologia , Humanos , Poluição por Fumaça de Tabaco/análise
10.
Environ Res ; 200: 111355, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34022230

RESUMO

OBJECTIVE: Due to partial or poorly enforced restrictions secondhand tobacco smoke (SHS) is still present in outdoor hospitality venues in many European countries. This study aimed to assess SHS concentrations in outdoor hospitality venues across Europe and identify contextual exposure determinants. METHODS: Cross-sectional study. We measured airborne nicotine and evidence of tobacco use in terraces of bars, cafeterias, and pubs from 11 European countries in 2017-2018. Sites were selected considering area-level socioeconomic indicators and half were visited during nighttime. We noted the smell of smoke, presence of smokers, cigarette butts, ashtrays, and number of physical covers. Contextual determinants included national smoke-free policies for the hospitality sector, the Tobacco Control Scale score (2016), and the national smoking prevalence (2017-2018). We computed medians and interquartile ranges (IQR) of nicotine concentrations and used multivariate analyses to characterize the exposure determinants. RESULTS: Nicotine was present in 93.6% of the 220 sites explored. Overall concentrations were 0.85 (IQR:0.30-3.74) µg/m3 and increased during nighttime (1.45 IQR:0.65-4.79 µg/m3), in enclosed venues (2.97 IQR:0.80-5.80 µg/m3), in venues with more than two smokers (2.79 IQR:1.03-6.30 µg/m3), in venues in countries with total indoor smoking bans (1.20 IQR:0.47-4.85 µg/m3), and in venues in countries with higher smoking prevalence (1.32 IQR:0.49-5.34 µg/m3). In multivariate analyses, nicotine concentrations were also positively associated with the observed number of cigarette butts. In venues with more than two smokers, SHS levels did not significantly vary with the venues' degree of enclosure. CONCLUSIONS: Our results suggest that current restrictions in outdoor hospitality venues across Europe have a limited protective effect and justify the adoption of total smoking bans in outdoor areas of hospitality venues.


Assuntos
Poluição do Ar em Ambientes Fechados , Política Antifumo , Poluição por Fumaça de Tabaco , Poluição do Ar em Ambientes Fechados/análise , Estudos Transversais , Europa (Continente) , Nicotina/análise , Restaurantes , Poluição por Fumaça de Tabaco/análise
11.
J Epidemiol ; 31(2): 145-151, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32249267

RESUMO

BACKGROUND: Population data on tobacco use and its determinants require continuous monitoring and careful inter-country comparison. We aimed to provide the most up-to-date estimates on tobacco smoking from a large cross-sectional survey, conducted in selected European countries. METHODS: Within the TackSHS Project, a face-to-face survey on smoking was conducted in 2017-2018 in 12 countries: Bulgaria, England, France, Germany, Greece, Ireland, Italy, Latvia, Poland, Portugal, Romania, and Spain, representing around 80% of the 432 million European Union (EU) adult population. In each country, a representative sample of around 1,000 subjects aged 15 years and older was interviewed, for a total of 11,902 participants. RESULTS: Overall, 25.9% of participants were current smokers (31.0% of men and 21.2% of women, P < 0.001), while 16.5% were former smokers. Smoking prevalence ranged from 18.9% in Italy to 37.0% in Bulgaria. It decreased with increasing age (compared to <45, multivariable odds ratio [OR] for ≥65 year, 0.31; 95% confidence interval [CI], 0.27-0.36), level of education (OR for low vs high, 1.32; 95% CI, 1.17-1.48) and self-rated household economic level (OR for low vs high, 2.05; 95% CI, 1.74-2.42). The same patterns were found in both sexes. CONCLUSIONS: These smoking prevalence estimates represent the most up-to-date evidence in Europe. From them, it can be derived that there are more than 112 million current smokers in the EU-28. Lower socio-economic status is a major determinant of smoking habit in both sexes.


Assuntos
Fumantes/estatística & dados numéricos , Fumar/epidemiologia , Adolescente , Adulto , Idoso , Estudos Transversais , Europa (Continente)/epidemiologia , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores Socioeconômicos , Adulto Jovem
12.
Indoor Air ; 31(5): 1601-1613, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33905602

RESUMO

Secondhand electronic cigarette (e-cigarette) aerosol (SHA) might impair indoor air quality and expose bystanders. This study aims to investigate exposure to SHA in controlled conditions of enclosed settings simulating real-world scenario. An experiment was performed in a car and in a room, in which SHA was generated during a 30-minute ad libitum use of an e-cigarette. The experiment was replicated on five consecutive days in each setting. We measured PM2.5 , airborne nicotine concentrations, and biomarkers of exposure to SHA, such as nicotine metabolites, tobacco-specific nitrosamines, propylene glycol, and glycerol in bystanders' saliva samples before, during, and after the exposure period. Self-reported health symptoms related to exposure to SHA were also recorded. The results showed that the highest median PM2.5 concentration was recorded during the exposure period, being 21 µg/m3 in the room setting and 16 µg/m3 in the car setting-about twofold increase compared to the baseline. Most concentrations of the airborne nicotine and all biomarkers were below the limit of quantification in both settings. Bystanders in both settings experienced some short-term irritation symptoms, expressed as dry throat, nose, eyes, and phlegm. In conclusion, short-term use of an e-cigarette in confined spaces increased indoor PM2.5 level and caused some irritation symptoms in bystanders.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos , Sistemas Eletrônicos de Liberação de Nicotina , Compostos Orgânicos Voláteis/análise , Poluição do Ar em Ambientes Fechados/análise , Espaços Confinados , Monitoramento Ambiental , Humanos , Nicotina , Produtos do Tabaco
13.
J Environ Manage ; 279: 111810, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33341726

RESUMO

Olive Mill Wastewater (OMW) is a polluting residue from the olive oil industry. It is usually stored in open-air unprotected evaporation ponds where their sediments accumulate. This study compares the characteristics of OMW sludges stored for long-time in evaporation ponds and assesses their impact on the underlying soil layer. Physicochemical parameters, toxicity bioassays, and full characterization of the microbial community were analyzed. The extension of the polluting effects was assessed by analysis of toxicity, microbial biomass carbon, and respiration. Geostatistics was used to predict their spatial distribution. Organic matter and polyphenol content besides toxicity levels determine variations between OMW sludges and have a high impact on the microbiota they contain. The microbial community was abundant, diverse, and functionally active. However, the biodegradability of the sludges was hindered by the toxicity levels. Toxicity and biomass carbon were higher on the surface of the ponds than in the soil layer revealing a reduced leach flow and depletion of contaminants. The natural microbiota might be biostimulated by means of applying sustainable and feasible biological treatments in order to favor the OMW sludges bioremediation. These results open up the possibility of solving the environmental concern caused by its storage in similar scenarios, which are common in olive oil-producing countries.


Assuntos
Microbiota , Olea , Biodegradação Ambiental , Resíduos Industriais/análise , Azeite de Oliva , Lagoas , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias
14.
FASEB J ; 33(2): 2199-2211, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30226811

RESUMO

Corneal immune privilege is integral in maintaining the clear avascular window to the foreign world. The presence of distinct populations of corneal leukocytes (CLs) in the normal cornea has been firmly established. However, their precise function and kinetics remain, as of yet, unclear. Through intravital multiphoton microscopy (IV-MPM), allowing the means to accumulate critical spatial and temporal cellular information, we provide details for long-term investigation of CL morphology and kinetics under steady state and following inflammation. Significant alterations in size and morphology of corneal CD11c+ dendritic cells (DCs) were noted following acute sterile inflammation, including cell volume (4364.4 ± 489.6 vs. 1787.6 ± 111.0 µm3, P < 0.001) and sphericity (0.82 ± 0.01 vs. 0.42 ± 0.02, P < 0.001) compared with steady state. Furthermore, IV-MPM analyses revealed alterations in both the CD11c+ DC and major histocompatibility complex class II (MHC)-II+ mature antigen-presenting cell population kinetics during inflammation, including track displacement length (CD11c: 16.57 ± 1.41 vs. 4.64 ± 0.56 µm, P < 0.001; MHC-II: 9.03 ± 0.37 vs. 4.09 ± 0.39, P < 0.001) and velocity (CD11c: 1.91 ± 0.07 µm/min vs. 1.73 ± 0.1302 µm/min; MHC-II: 2.97 ± 0.07 vs. 1.62 ± 0.08, P < 0.001) compared with steady state. Our results reveal in vivo evidence of sessile CL populations exhibiting dendritic morphology under steady state and increased velocity of spherical leukocytes following inflammation. IV-MPM represents a powerful tool to study leukocytes in corneal diseases in context.-Seyed-Razavi, Y., Lopez, M. J., Mantopoulos, D., Zheng, L., Massberg, S., Sendra, V. G., Harris, D. L., Hamrah, P. Kinetics of corneal leukocytes by intravital multiphoton microscopy.


Assuntos
Córnea/citologia , Leucócitos/citologia , Microscopia/métodos , Animais , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fótons
15.
Chemphyschem ; 21(10): 1012-1018, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32233111

RESUMO

The adsorption of molecular deuterium (D2 ) onto charged cobalt-fullerene-complexes Con C60 + (n=1-8) is measured experimentally in a few-collision reaction cell. The reactivity is strongly size-dependent, hinting at clustering of the transition metal atoms on the fullerenes. Formation and desorption rate constants are obtained from the pressure-dependent deuterogenation curves. DFT calculations indeed find that this transition metal clustering is energetically more favorable than decorating the fullerene. For n=1, D2 is predicted to bind molecularly and for n=2 dissociative and molecular configurations are quasi-isoenergetic. For n=3-8, dissociation of D2 is thermodynamically preferred. However, reaching the ground state configuration with dissociated deuterium on the timescale of the experiment may be hindered by dissociation barriers.

16.
J Phys Chem A ; 124(32): 6468-6477, 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32668160

RESUMO

Ag and Co metals do not form macroscopic solid or liquid alloys. However, AgmCon clusters have been produced in dual-target dual-laser vaporization experiments, and the same occurs for other pairs of immiscible metals. We have performed density functional calculations to shed light on this phenomenon. The main result, obtained for clusters with sizes m + n not larger than 11, is that the cohesive energies justify that those clusters can be formed starting from free Ag and Co atoms, which is the case in the vaporization experiments. At the same time, mixing of Ag and Co is difficult even at the nanoscale. This is revealed by the application of several miscibility criteria. Those two features become, nevertheless, compatible in the clusters. Even if the cluster sizes considered are small, the emerging trend becomes clear: Co atoms form a core in the inner part, surrounded by a shell of Ag atoms on the surface. A consequence is that core-shell clusters can be formed from pairs of metals that do not form macroscopic alloys. The magnetic moments µ of the AgmCon clusters are due mainly to the Co atoms, and the presence of Ag induces a reduction in the magnitude of µ.

17.
BMC Public Health ; 20(1): 26, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31914967

RESUMO

BACKGROUND: From 2000 to 2008, in urban areas in Spain, adolescent fertility and abortion rates underwent unprecedented increases, consecutive to intensive immigration from developing countries. To address unmet needs for contraception information and services, a community-based, gender-sensitive and culturally adapted brief counselling intervention (SIRIAN program) was launched in some deprived neighbourhoods with a high proportion of immigrants in Barcelona. Once a randomized controlled trial demonstrated its effectiveness in increasing the use of contraceptives, we aim to examine its population impact on adolescent fertility rates. METHODS: Quasi-experimental study with comparison group, using population data from 2005 to 2016. Five neighbourhoods in the lowest tercile of Disposable Household Income were intervened in 2011-13. The comparison group included the three neighbourhoods which were in the same municipal district and in the lowest Disposable Household Income tercile, and displayed the highest adolescent fertility rates. Generalized linear models were fitted to assess absolute adolescent fertility rates and adjusted by immigrant population between pre-intervention (2005-10) and post-intervention periods (2011-16); Difference in Differences and relative pre-post changes analysis were performed. RESULTS: In 2005-10 the intervention group adolescent fertility rate was 27.90 (per 1000 women 15-19) and 21.84 in the comparison group. In 2011-16 intervention areas experienced great declines (adolescent fertility rate change: - 12.30 (- 12.45 to - 12.21); p < 0.001), while comparison neighbourhoods remained unchanged (adolescent fertility rate change: 1.91 (- 2.25 to 6.07); p = 0.368). A reduction of - 10.97 points (- 13.91 to - 8.03); p < 0.001) is associated to the intervention. CONCLUSION: Adolescent fertility rate significantly declined in the intervention group but remained stable in the comparison group. This quasi-experimental study provide evidence that, in a country with universal health coverage, a community counselling intervention that increases access to contraception, knowledge and sexual health care in hard-to-reach segments of the population can contribute to substantially reduce adolescent fertility rates. Reducing adolescent fertility rates could become a feasible goal in cities with similar conditions.


Assuntos
Coeficiente de Natalidade/tendências , Serviços de Saúde Comunitária , Anticoncepção/psicologia , Aconselhamento , Adolescente , Cidades , Anticoncepção/estatística & dados numéricos , Anticoncepcionais/administração & dosagem , Emigrantes e Imigrantes/psicologia , Emigrantes e Imigrantes/estatística & dados numéricos , Feminino , Necessidades e Demandas de Serviços de Saúde , Humanos , Áreas de Pobreza , Gravidez , Avaliação de Programas e Projetos de Saúde , Características de Residência/estatística & dados numéricos , Espanha , Adulto Jovem
18.
J Environ Manage ; 265: 110528, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32421558

RESUMO

Biological transformation of municipal solid waste is an environment-friendly management strategy against recalcitrant residues. The bacterial biome that inhabit said residues are responsible of decomposing both simple and complex materials. For this reason, processes such as composting, which favor the acceleration of the transformation of organic matter, can contribute to the degradation of municipal solid waste. Not only as mere fertilizer for crops, but also as methods for the recovery of solid waste. However, the control of the conditions necessary to achieve an optimal process on an industrial scale is a great concern. Thus, the aim of this work focuses on the characterization of the bacterial microbiome on three municipal solid waste facilities in order to deepen the role of microorganisms in the state of the final product obtained. For it, an intensive metagenomic analysis as well as a battery of physicochemical determinations were carried out. The lack of adequate thermophilic phases was decisive in finding certain bacterial genera, such as Lactobacillus, which was significant through these processes. Biodiversity did not follow a common pattern in the three processes, neither in abundance nor in richness but, in general, it was greater during the bio-oxidative stage. Despite the different trend in terms of the degradation of carbon fractions in these wastes, at the end of the biodegradation treatments, a sufficient degree of bioestabilization of the organic matter was reached. The results offer the opportunity to obtain a level of detail unprecedented of the structure, dynamics and function of the bacterial community in real conditions, without the control offered by laboratory conditions or pilot plants.


Assuntos
Compostagem , Microbiota , Eliminação de Resíduos , Gerenciamento de Resíduos , Fertilizantes , Solo , Resíduos Sólidos
19.
Phys Chem Chem Phys ; 21(41): 22919-22929, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31596286

RESUMO

Metals which are not miscible in the bulk solid phase can form clusters at the nanoscale, and a typical example is the Al-Sn system. We have investigated the reasons for the enhanced miscibility occurring at the nanoscale. Density functional calculations have been performed for small AlmSnn clusters at all compositions when the total number of atoms N = m + n is equal to or smaller than N = 6, and for selected compositions for N = 10 and N = 11. The cohesive energies show that the clusters are energetically stable with respect to the separated atoms. Also, after an AlmSnn cluster has formed, its separation into two pure clusters Alm and Snn is energetically forbidden. This justifies the observation that those clusters can form by condensation in gas phase experiments. The different miscibility criteria explored reveal a substantial dependence on the reference state. Between those miscibility criteria, a particularly valuable one consists in studying the substitution reactions in which an Al atom of the gas replaces a Sn atom of the AlmSnn cluster to produce Alm+1Snn-1, or a Sn atom replaces an Al atom to produce Alm-1Snn+1. The conclusion is that substitution reactions enriching the clusters in Sn and depleting the cluster in Al are favorable. However, AlSn10 is an exception to this general trend. This is a special cluster. It readily forms by replacing a Sn atom by an Al atom in Sn11. Also, AlSn10 forms easily by adding an Al atom to Sn10. The geometric structures of Sn11 and Sn10 easily reorganize to form AlSn10 accommodating the Al atom inside a Sn cage. The exceptionally stable character of AlSn10 justifies the identification of AlSn10 as a magic cluster with the highest population in the measured mass spectra of this family. Even if Al and Sn can form clusters, the degree of mixing of these two elements in the clusters is modest, and a tendency for segregation of Al and Sn atoms on different parts of the cluster is incipient.

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