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1.
Proc Natl Acad Sci U S A ; 121(17): e2316452121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38621125

RESUMO

The main sources of redox gradients supporting high-productivity life in the Europan and other icy ocean world oceans were proposed to be photolytically derived oxidants, such as reactive oxygen species (ROS) from the icy shell, and reductants (Fe(II), S(-II), CH4, H2) from bottom waters reacting with a (ultra)mafic seafloor. Important roadblocks to maintaining life, however, are that the degree of ocean mixing to combine redox species is unknown, and ROS damage biomolecules. Here, we envisage a unique solution using an acid mine drainage (AMD)-filled pit lakes analog system for the Europan ocean, which previous models predicted to be acidic. We hypothesize that surface-generated ROS oxidize dissolved Fe(II) resulting in Fe(III) (hydr)oxide precipitates, that settle to the seafloor as "iron snow." The iron snow provides a respiratory substrate for anaerobic microorganisms ("breathing iron"), and limits harmful ROS exposure since they are now neutralized at the ice-water interface. Based on this scenario, we calculated Gibbs energies and maximal biomass productivities of various anaerobic metabolisms for a range of pH, temperatures, and H2 fluxes. Productivity by iron reducers was greater for most environmental conditions considered, whereas sulfate reducers and methanogens were more favored at high pH. Participation of Fe in the metabolic redox processes is largely neglected in most models of Europan biogeochemistry. Our model overcomes important conceptual roadblocks to life in icy ocean worlds and broadens the potential metabolic diversity, thus increasing total primary productivity, the diversity and volume of habitable environmental niches and, ultimately, the probability of biosignature detection.


Assuntos
Gelo , Ferro , Espécies Reativas de Oxigênio , Neve , Oxirredução , Compostos Ferrosos
2.
Proc Natl Acad Sci U S A ; 120(9): e2217125120, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36802438

RESUMO

Sodium chloride is expected to be found on many of the surfaces of icy moons like Europa and Ganymede. However, spectral identification remains elusive as the known NaCl-bearing phases cannot match current observations, which require higher number of water of hydration. Working at relevant conditions for icy worlds, we report the characterization of three "hyperhydrated" sodium chloride (SC) hydrates, and refined two crystal structures [2NaCl·17H2O (SC8.5); NaCl·13H2O (SC13)]. We found that the dissociation of Na+ and Cl- ions within these crystal lattices allows for the high incorporation of water molecules and thus explain their hyperhydration. This finding suggests that a great diversity of hyperhydrated crystalline phases of common salts might be found at similar conditions. Thermodynamic constraints indicate that SC8.5 is stable at room pressure below 235 K, and it could be the most abundant NaCl hydrate on icy moon surfaces like Europa, Titan, Ganymede, Callisto, Enceladus, or Ceres. The finding of these hyperhydrated structures represents a major update to the H2O-NaCl phase diagram. These hyperhydrated structures provide an explanation for the mismatch between the remote observations of the surface of Europa and Ganymede and previously available data on NaCl solids. It also underlines the urgent need for mineralogical exploration and spectral data on hyperhydrates at relevant conditions to help future icy world exploration by space missions.

3.
Philos Trans A Math Phys Eng Sci ; 382(2273): 20230201, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38736335

RESUMO

The Cassini mission provided evidence for a global subsurface ocean and ongoing hydrothermal activity on Enceladus, based on results from Cassini's mass spectrometers. Laboratory simulations of hydrothermal conditions on icy moons are needed to further constrain the composition of ejected ice grains containing hydrothermally altered organic material. Here, we present results from our newly established facility to simulate the processing of ocean material within the temperature range 80-150°C and the pressure range 80-130 bar, representing conditions suggested for the water-rock interface on Enceladus. With this new facility, we investigate the hydrothermal processing of triglycine (GGG) peptide and, for the first time, analyse the extracted samples using laser-induced liquid beam ion desorption (LILBID) mass spectrometry, a laboratory analogue for impact ionization mass spectrometry of ice grains in space. We outline an approach to elucidate hydrothermally processed GGG in ice grains ejected from icy moons based on characteristic differences between GGG anion and cation mass spectra. These differences are linked to hydrothermal processing and thus provide a fingerprint of hydrothermal activity on extraterrestrial bodies. These results will serve as important guidelines for biosignatures potentially obtained by a future Enceladus mission and the SUrface Dust Analyzer (SUDA) instrument onboard Europa Clipper. This article is part of the theme issue 'Dust in the Solar System and beyond'.

4.
Sensors (Basel) ; 24(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38732881

RESUMO

Subsurface exploration of ice-covered planets and moons presents communications challenges because of the need to communicate through kilometers of ice. The objective of this task is to develop the capability to wirelessly communicate through kilometers of ice and thus complement the potentially failure-prone tethers deployed behind an ice-penetrating probe on Ocean Worlds. In this paper, the preliminary work on the development of wireless deep-ice communication is presented and discussed. The communication test and acoustic attenuation measurements in ice have been made by embedding acoustic transceivers in glacial ice at the Matanuska Glacier, Anchorage, Alaska. Field test results show that acoustic communication is viable through ice, demonstrating the transmission of data and image files in the 13-18 kHz band over 100 m. The results suggest that communication over many kilometers of ice thickness could be feasible by employing reduced transmitting frequencies around 1 kHz, though future work is needed to better constrain the likely acoustic attenuation properties through a refrozen borehole.

5.
Conserv Biol ; 36(5): e13930, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35510330

RESUMO

Soil biodiversity and related ecosystem functions are neglected in most biodiversity assessments and nature conservation actions. We examined how society, and particularly policy makers, have addressed these factors worldwide with a focus on Europe and explored the role of soils in nature conservation in Germany as an example. We reviewed past and current global and European policies, compared soil ecosystem functioning in- and outside protected areas, and examined the role of soils in nature conservation management via text analyses. Protection and conservation of soil biodiversity and soil ecosystem functioning have been insufficient. Soil-related policies are unenforceable and lack soil biodiversity conservation goals, focusing instead on other environmental objectives. We found no evidence of positive effects of current nature conservation measures in multiple soil ecosystem functions in Europe. In German conservation management, soils are considered only from a limited perspective (e.g., as physicochemical part of the environment and as habitat for aboveground organisms). By exploring policy, evidence, and management as it relates to soil ecosystems, we suggest an integrative perspective to move nature conservation toward targeting soil ecosystems directly (e.g., by setting baselines, monitoring soil threats, and establishing a soil indicator system).


La biodiversidad del suelo y las funciones ambientales relacionadas se dejan de lado en la mayoría de las evaluaciones de la biodiversidad y de las acciones de conservación de la naturaleza. Analizamos cómo la sociedad, y particularmente los formuladores de políticas, han abordado estos factores a nivel mundial con un enfoque en Europa y exploramos como ejemplo el papel de los suelos en la conservación de la naturaleza en Alemania. Revisamos las políticas mundiales y europeas en el pasado y en la actualidad, comparamos el funcionamiento ambiental del suelo dentro y fuera de las áreas protegidas y examinamos el papel de los suelos en la gestión de la conservación por medio del análisis de textos. La protección y la conservación de la biodiversidad y el funcionamiento ambiental del suelo han sido insuficientes. Las políticas relacionadas con el suelo son inaplicables y carecen de objetivos de conservación para su biodiversidad, pues se enfocan más bien en otros objetivos ambientales. No descubrimos evidencias de los efectos positivos de las medidas actuales de conservación en múltiples funciones ambientales del suelo en Europa. En la gestión alemana de la conservación, los suelos sólo se consideran desde una perspectiva limitada (p. ej.: como una parte físico química del ambiente y como hábitat para los organismos que habitan por encima de él). Mediante la exploración de la política, evidencias y gestión conforme se relaciona con los ecosistemas del suelo, sugerimos una perspectiva integrada para dirigir a la conservación hacia el enfoque directo sobre los ecosistemas del suelo (p. ej.: al establecer líneas base, monitorear las amenazas para el suelo y establecer un sistema indicador del suelo).


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Solo , Ecossistema , Europa (Continente)
6.
Geophys Res Lett ; 49(5): e2021GL096939, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35866068

RESUMO

Habitable ocean environments on Europa require an influx of reactants to maintain chemical disequilibrium. One possible source of reactants is seafloor volcanism. Modeling has shown that dissipation of tidal energy in Europa's asthenosphere can generate melt, but melt formation cannot be equated with volcanism. Melt must also be transported through Europa's cold lithosphere to erupt at the seafloor. Here, we use two models of dike propagation to show that dikes can only traverse the lithosphere if either the fracture toughness of the lithosphere or the flux into the dike is large (>500 MPa m1/2 or ∼1 m2 s-1, respectively). We conclude that cyclic volcanic episodes might provide reactants to Europa's ocean if magma accumulates at the base of the lithosphere for several thousand years. However, if dikes form too frequently, or are too numerous, the magma flux into each will be insufficient, and volcanism cannot support a habitable ocean environment.

7.
Ecol Appl ; 31(3): e02256, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33164249

RESUMO

Most parasites and pathogens infect multiple hosts, but a great deal of variation exists in the role of those hosts in persistence of infection. Understanding which hosts are most important in maintaining parasites can provide a clearer target for infection control. Recently developed empirical and theoretical approaches provide a way to quantify the relative contribution of hosts within a community and place them in a multi-host framework to better direct control efforts. Amphibians provide a framework for better understanding multi-host-multi-parasite dynamics. Two well-studied amphibian parasites, Batrachochytrium dendrobatidis (Bd) and Ranavirus, infect multiple host species and exhibit a great deal of heterogeneity in how they affect hosts. We used these two parasites and a community of five amphibian species to investigate the relative importance of hosts in parasite persistence, and how any patterns varied spatially and temporally. At two sites (Lake Ercina and Lake Lloroza in the Picos de Europa National Park, Spain) we collected data on the prevalence and shedding rate of parasite infection for both Bd and Ranavirus, and the abundance of each species' life stages. We used these data to parameterize a recently developed modeling framework, which was used to quantify the relative contribution of each host to the community reproductive number, R0 . By comparing each host-category over time and between sites we were able to identify consistencies in which host was responsible for the maintenance of these two parasites. Within a site one species consistently contributed the most to the persistence of both parasites. This consistency did not transfer between sites, the maintenance host species being different for each. At one site (Ercina), life stages of the common midwife toad, Alytes obstetricans, acted as the maintenance host for both Bd and Ranavirus. In contrast, at the second site, Lloroza, the alpine newt, Ichthyosaura alpestris, fulfilled that role. A single host species was responsible for infection persistence of both parasites at each lake. Attempts to control the infection levels and impacts of multiple parasites can benefit from a community epidemiology approach, and provide clarity on which hosts are the foci of mitigation efforts. However, at a small spatial scale, the target host may vary according to the physical qualities of those sites and the demographics of the host community.


Assuntos
Quitridiomicetos , Micoses , Parasitos , Ranavirus , Anfíbios , Animais , Espanha
8.
Geophys Res Lett ; 48(18): e2021GL094143, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-35865189

RESUMO

Europa likely contains an iron-rich metal core. For it to have formed, temperatures within Europa reached ≳ 1250 K. Going up to that temperature, accreted chondritic minerals - for example, carbonates and phyllosilicates - would partially devolatilize. Here, we compute the amounts and compositions of exsolved volatiles. We find that volatiles released from the interior would have carried solutes, redox-sensitive species, and could have generated a carbonic ocean in excess of Europa's present-day hydrosphere, and potentially an early CO 2 atmosphere. No late delivery of cometary water was necessary. Contrasting with prior work, CO 2 could be the most abundant solute in the ocean, followed by Ca 2 + , SO 4 2 - , and HCO 3 - . However, gypsum precipitation going from the seafloor to the ice shell decreases the dissolved S/Cl ratio, such that Cl > S at the shallowest depths, consistent with recently inferred endogenous chlorides at Europa's surface. Gypsum would form a 3-10 km thick sedimentary layer at the seafloor.

9.
Fam Process ; 60(1): 145-158, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32293039

RESUMO

Joint physical custody, a parental care arrangement in which a child lives with each parent about equally after separation or divorce, is an increasingly common phenomenon in many Western countries. Although attention from family scholars, practitioners, and law professionals is growing, there are hardly any numbers on the prevalence of joint physical custody (JPC). Moreover, studies using large-scale representative data on the effects of JPC for children's well-being are still rare. The data for this study come from Health Behaviour in School-Aged Children (HBSC), a representative cross-national survey of adolescents in 37 European and North American countries that was conducted in 2002, 2006, and 2010 and included information on students at the ages of 11, 13, and 15 years (N = 92,886). First, results revealed that symmetrical JPC after family dissolution is still very rare in the majority of countries (5% or less), but reaches 10-20% in some countries. Second, adolescents' life satisfaction in nonintact families is higher in symmetric JPC arrangements than in asymmetric care arrangements. However, after controlling for children and family characteristics, the differences disappear. Thus, it is not the symmetric JPC arrangement that induces adolescents' higher life satisfaction, but rather the children and family characteristics that are associated with the choice of such a custody arrangement by separated or divorced parents.


La custodia física conjunta, un acuerdo de cuidado parental por medio del cual un niño vive con cada padre más o menos por igual después de la separación o el divorcio, es un fenómeno cada vez más común en muchos países occidentales. Aunque la atención por parte de los investigadores familiares, los profesionales de la salud y los abogados está aumentando, hay muy pocas cifras sobre el predominio de la custodia física conjunta. Además, los estudios que utilizan datos representativos a gran escala sobre los efectos de la custodia física conjunta para el bienestar de los niños todavía son escasos. Los datos para este estudio provienen del Estudio sobre las conductas saludables de los jóvenes escolarizados (Health Behaviour in School-Aged Children, HBSC), una encuesta transnacional representativa de adolescentes en 37 países europeos y norteamericanos que se realizó en 2002, 2006 y 2010 e incluyó información sobre alumnos a las edades de 11, 13, y 15 años (N=92,886). En primer lugar, los resultados revelaron que la custodia física conjunta simétrica después de la división familiar aun es muy rara en la mayoría de los países (5 % o menos), pero llega a entre el 10 y el 20 % en algunos países. En segundo lugar, la satisfacción con la vida de los adolescentes en familias no intactas es mayor en los acuerdos de custodia física conjunta simétrica que en los acuerdos de cuidado asimétrico. Sin embargo, después de tener en cuenta las características de los niños y las familias, las diferencias desaparecen. Por lo tanto, no es el acuerdo de custodia física conjunta simétrica lo que causa una mayor satisfacción con la vida en los adolescentes, sino las características de los niños y las familias que están asociadas con la elección de dicho acuerdo de custodia por parte de los padres separados o divorciados.


Assuntos
Custódia da Criança , Satisfação Pessoal , Adolescente , Criança , Divórcio , Características da Família , Humanos , Pais
10.
Aten Primaria ; 53(8): 102134, 2021 10.
Artigo em Espanhol | MEDLINE | ID: mdl-34237607

RESUMO

We describe the role of primary care (PC) in 12 European countries in relation to the COVID-19 pandemic. There is no official information at European level on the activity of PC. The findings were: All countries provided COVID-19 information through telephone lines and websites to their citizens. Contact tracing was mainly carried out by Public Health except for Ireland, Portugal and Spain. The epidemiological surveillance task has overlapped with the PC assistance. Active Infection Diagnostic Tests (AIDT) were performed in PC exclusively in Spain. The other countries performed them in external laboratories. Patients were followed-up in PC mostly by remote assessment. Health coverage for vulnerable populations and nursing homes has been regulated in all countries. There is a need for a strategic plan for PC in Europe that responds to the challenges posed.


Assuntos
COVID-19 , Pandemias , Europa (Continente)/epidemiologia , Humanos , Atenção Primária à Saúde , SARS-CoV-2
11.
Aten Primaria ; 53(10): 102132, 2021 12.
Artigo em Espanhol | MEDLINE | ID: mdl-34256236

RESUMO

This article describes the management of human resource and the vaccination strategies in primary care in twelve European countries in relation to the COVID-19 pandemic. All the countries have found solutions to increase their workforce in primary care. Other healthcare professionals were incorporated to support family doctors assuming their tasks, under their supervision and coordination. The European Commission had a crucial role in the production, purchase and distribution of the vaccines. The engagement of primary care in the vaccination campaign has had an unequal participation in the different countries, although the greatest burden has been managed from the government's public health departments.


Assuntos
COVID-19 , Europa (Continente) , Humanos , Pandemias/prevenção & controle , Atenção Primária à Saúde , SARS-CoV-2 , Vacinação , Recursos Humanos
12.
J Anim Ecol ; 89(1): 20-28, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31628669

RESUMO

The early life of animals is a period of high mortality, when foraging capacities are assumed to be improved progressively. In birds, this critical period involves the improvement of the flight. How do young birds gain these capacities has rarely been studied in natural conditions especially in seabirds that spend most of their life at sea. We used detailed GPS and body acceleration data on 37 great frigatebirds (Fregata minor), to test the hypothesis that juveniles starting their first flights have lower flying capacities than adults, but that these capacities will improve during a long learning period, before independence from parents, specific to this seabird that can spend months on the wing at sea. We found that most flight components improved over time to tend towards those of adults, especially the travel speed, range, duration and maximum altitude of trips. However, unexpectedly, juveniles had higher ascent rates, soaring and gliding capacities above the sea than adults. Moreover, energy expenditure of juveniles was similar to adults during low cost travelling movements and during active foraging, but juveniles spent more time foraging actively than adults. Our results suggest that flight tactics based on long-distance effortless movements specific to this family are acquired during a long period, but soaring and gliding capacities are already inherited by juveniles and possibly favoured by morphological adaptations specific to juveniles. These adaptations might explain the extreme dispersive capacities of juveniles.


Assuntos
Aves , Voo Animal , Altitude , Animais , Metabolismo Energético , Asas de Animais
13.
Risk Anal ; 40(4): 842-857, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31943320

RESUMO

The Europa mission approved in 2019 is still in the development phase. It is designed to conduct a detailed reconnaissance of that moon of Jupiter as it could possibly support life as we know it. This article is based on a top-down approach (mission → system → subsystems → components) to model the probability of mission failure. The focus here is on the case where the (uncertain) radiation load exceeds the (uncertain) capacity of critical subsystems of the spacecraft. The model is an illustrative quantification of the uncertainties about (1) the complex external radiation environment in repeated exposures, (2) the effectiveness of the shielding in different zones of the spacecraft, and (3) the components' capacities, by modeling all three as dynamic random variables. A simulation including a sensitivity analysis is used to obtain the failure probability of the whole mission in forty-five revolutions around Jupiter. This article illustrates how probabilistic risk analysis based on engineering models, test results and expert opinions can be used in the early stages of the design of space missions when uncertainties are large. It also describes the optimization of the spacecraft design, taking into account the decisionmakers' risk attitude and the mission resource constraints.


Assuntos
Radiação Cósmica , Probabilidade , Medição de Risco , Astronave , Júpiter
14.
Gastroenterol Hepatol ; 42(10): 595-603, 2019 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31519387

RESUMO

INTRODUCTION: In Europe, gastric adenocarcinoma (GADC) is commonly regarded as a disease of the elderly. This study aims to assess the proportion, characteristics, and survival of patients diagnosed with GADC under the age of 60. MATERIALS AND METHODS: This is a retrospective, multicentric, and analytical study conducted at four tertiary Spanish hospitals. All patients diagnosed with GADC between 2008 and 2015 were included. Demographic, clinical, endoscopic, histologic, and survival data were retrieved. A multivariate analysis was performed to compare GADC in young (age≤60 years) and elderly patients. RESULTS: A total of 1374 patients with GADC were included. The mean age was 74 years (SD:11.1); 62.2% were males. There were 177 patients under the age of 60 (12.9%, 95% CI: 11.2-14.8%). GADC was frequently encountered as a metastatic disease in both young and elderly patients (Stage IV: 45.7% and 41%, respectively). In the multivariate analysis, alcohol abuse, ASA functional status I-II, diffuse subtype, neoadjuvant, and palliative therapy were independently associated (P<0.05) with age ≤60 years. No differences were found in 2-year survival (GADC ≤60: 39% vs. 35%, P=0.45). Curative-intent surgery, TNM stage I-II, body mass index<30kg/m2, and better functional status at diagnosis were independent predictors of survival in GADC under the age of 60. CONCLUSIONS: One out of eight cases of GADC were diagnosed under the age of 60. Metastatic disease was frequent at diagnosis and overall survival was poor regardless of age. Factors associated with localized disease correlated with improved survival in younger patients. Our results underline the need for early diagnosis strategies in our country.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Adenocarcinoma/diagnóstico , Adenocarcinoma/mortalidade , Adenocarcinoma/terapia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Espanha/epidemiologia , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/terapia , Análise de Sobrevida , Taxa de Sobrevida
15.
Electrophoresis ; 39(22): 2864-2871, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30216482

RESUMO

The search for biosignatures on spaceflight missions requires in situ instrumentation capable of highly selective and sensitive organic analyses. To this end, CE-LIF is a uniquely promising technique, capable of determining the type, abundance, and chirality of amino acids present in environmental samples at nanomolar concentrations. However, this type of assay requires several reagents that have not yet been used on spaceflight missions. A key concern, particularly for future missions to Europa, is the survivability of these critical components for CE separation and LIF detection under high levels of radiation. Here we present an investigation of the chemical stability of the reagents and associated fused silica capillary after a total ionizing dose of 300 krad, exceeding the predicted total ionizing dose for the potential Europa Lander Mission payload by two-fold. Neither the fused silica capillary nor the fluorescent dye (5-carboxyfluorescein succinimidyl ester) showed significant change in performance following irradiation. Following the irradiation of the pre-mixed background electrolyte, both migration time and resolution were affected. However, when the reagents (sodium tetraborate, sodium taurocholate, and γ-cyclodextrin) and the acetonitrile solution were irradiated separately and mixed afterwards, there was no change in the separation performance.


Assuntos
Aminoácidos/análise , Eletroforese Capilar , Indicadores e Reagentes , Voo Espacial , Estabilidade de Medicamentos , Eletroforese Capilar/métodos , Eletroforese Capilar/normas , Raios gama , Indicadores e Reagentes/análise , Indicadores e Reagentes/química , Indicadores e Reagentes/efeitos da radiação , Estereoisomerismo
16.
Trop Med Int Health ; 22(4): 454-464, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28072493

RESUMO

OBJECTIVE: To determine the causative agents of infections and their antimicrobial susceptibility at a tertiary care hospital in Moshi, Tanzania, to guide optimal treatment. METHODS: A total of 590 specimens (stool (56), sputum (122), blood (126) and wound swabs (286)) were collected from 575 patients admitted in the medical and surgical departments. The bacterial species were determined by conventional methods, and disc diffusion was used to determine the antimicrobial susceptibility pattern of the bacterial isolates. RESULTS: A total of 249 (42.2%) specimens were culture-positive yielding a total of 377 isolates. A wide range of bacteria was isolated, the most predominant being Gram-negative bacteria: Proteus spp. (n = 48, 12.7%), Escherichia coli (n = 44, 11.7%), Pseudomonas spp. (n = 40, 10.6%) and Klebsiella spp (n = 38, 10.1%). Wound infections were characterised by multiple isolates (n = 293, 77.7%), with the most frequent being Proteus spp. (n = 44, 15%), Pseudomonas (n = 37, 12.6%), Staphylococcus (n = 29, 9.9%) and Klebsiella spp. (n = 28, 9.6%). All Staphylococcus aureus tested were resistant to penicillin (n = 22, 100%) and susceptible to vancomycin. Significant resistance to cephalosporins such as cefazolin (n = 62, 72.9%), ceftriaxone (n = 44, 51.8%) and ceftazidime (n = 40, 37.4%) was observed in Gram-negative bacteria, as well as resistance to cefoxitin (n = 6, 27.3%) in S. aureus. CONCLUSION: The study has revealed a wide range of causative agents, with an alarming rate of resistance to the commonly used antimicrobial agents. Furthermore, the bacterial spectrum differs from those often observed in high-income countries. This highlights the imperative of regular generation of data on aetiological agents and their antimicrobial susceptibility patterns especially in infectious disease endemic settings. The key steps would be to ensure the diagnostic capacity at a sufficient number of sites and implement structures to routinely exchange, compare, analyse and report data. Sentinel sites (hospitals) across the country (and region) should report on a representative subset of bacterial species and their susceptibility to drugs at least annually. A central organising body should collate the data and report to relevant national and international stakeholders.


Assuntos
Antibacterianos/farmacologia , Bactérias/crescimento & desenvolvimento , Infecções Bacterianas/microbiologia , Farmacorresistência Bacteriana , Resistência a Múltiplos Medicamentos , Centros de Atenção Terciária , Adulto , Antibacterianos/uso terapêutico , Bactérias/isolamento & purificação , Infecções Bacterianas/tratamento farmacológico , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tanzânia
17.
Conserv Biol ; 31(3): 570-580, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27601287

RESUMO

Protected areas are a cornerstone for forest protection, but they are not always effective during times of socioeconomic and institutional crises. The Carpathian Mountains in Eastern Europe are an ecologically outstanding region, with widespread seminatural and old-growth forest. Since 1990, Carpathian countries (Czech Republic, Hungary, Poland, Romania, Slovakia, and Ukraine) have experienced economic hardship and institutional changes, including the breakdown of socialism, European Union accession, and a rapid expansion of protected areas. The question is how protected-area effectiveness has varied during these times across the Carpathians given these changes. We analyzed a satellite-based data set of forest disturbance (i.e., forest loss due to harvesting or natural disturbances) from 1985 to 2010 and used matching statistics and a fixed-effects estimator to quantify the effect of protection on forest disturbance. Protected areas in the Czech Republic, Slovakia, and the Ukraine had significantly less deforestation inside protected areas than outside in some periods; the likelihood of disturbance was reduced by 1-5%. The effectiveness of protection increased over time in these countries, whereas the opposite was true in Romania. Older protected areas were most effective in Romania and Hungary, but newer protected areas were more effective in Czech Republic, and Poland. Strict protection (International Union for Conservation of Nature [IUCN] protection category Ia-II) was not more effective than landscape-level protection (IUCN III-VI). We suggest that the strength of institutions, the differences in forest privatization, forest management, prior distribution of protected areas, and when countries joined the European Union may provide explanations for the strikingly heterogeneous effectiveness patterns among countries. Our results highlight how different the effects of protected areas can be at broad scales, indicating that the effectiveness of protected areas is transitory over time and space and suggesting that generalizations about the effectiveness of protected areas can be misleading.


Assuntos
Conservação dos Recursos Naturais , Florestas , União Europeia , Humanos
18.
Proc Natl Acad Sci U S A ; 111(48): E5123-32, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25404343

RESUMO

We report far-ultraviolet observations of Jupiter's moon Europa taken by Space Telescope Imaging Spectrograph (STIS) of the Hubble Space Telescope (HST) in January and February 2014 to test the hypothesis that the discovery of a water vapor aurora in December 2012 by local hydrogen (H) and oxygen (O) emissions with the STIS originated from plume activity possibly correlated with Europa's distance from Jupiter through tidal stress variations. The 2014 observations were scheduled with Europa near the apocenter similar to the orbital position of its previous detection. Tensile stresses on south polar fractures are expected to be highest in this orbital phase, potentially maximizing the probability for plume activity. No local H and O emissions were detected in the new STIS images. In the south polar region where the emission surpluses were observed in 2012, the brightnesses are sufficiently low in the 2014 images to be consistent with any H2O abundance from (0-5)×10(15) cm(-2). Large high-latitude plumes should have been detectable by the STIS, independent of the observing conditions and geometry. Because electron excitation of water vapor remains the only viable explanation for the 2012 detection, the new observations indicate that although the same orbital position of Europa for plume activity may be a necessary condition, it is not a sufficient condition. However, the December 2012 detection of coincident HI Lyman-α and OI 1304-Å emission surpluses in an ∼200-km high region well separated above Europa's limb is a firm result and not invalidated by our 2014 STIS observations.


Assuntos
Meio Ambiente Extraterreno , Júpiter , Vapor , Água/análise , Exobiologia/métodos , Hidrogênio/análise , Hidrogênio/química , Gelo , Oxigênio/análise , Oxigênio/química , Telescópios , Água/química
19.
Enferm Infecc Microbiol Clin ; 35(1): 47-51, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26481661

RESUMO

Immigrant populations, especially those from endemic countries, living in the European Union (EU) suffer a disproportionate burden of HIV, delayed diagnosis and poorer access to antiretroviral treatment. While International Organisations are developing recommendations aimed at increasing the uptake of HIV testing, the feasibility and real outcomes of these measures remain unexplored. The aim of this review was, firstly to identify the recommendations of the main International Organisations (IO) on HIV testing in immigrants. Secondly, to describe the challenges for implementing and expanding HIV testing and counselling interventions targeting immigrants by interviewing key informants. The importance of HIV testing in immigrants is discussed, along with the appropriateness of universal HIV testing approaches vs most at risk targeted approaches. Also addressed is, pre- and post-HIV test counselling characteristics and community initiatives suitable to reach this population and, finally the legal issues regarding access to treatment for illegal immigrants.


Assuntos
Sorodiagnóstico da AIDS/estatística & dados numéricos , Emigrantes e Imigrantes , Infecções por HIV/diagnóstico , Infecções por HIV/prevenção & controle , Programas de Rastreamento , Europa (Continente) , Prova Pericial , Humanos , Guias de Prática Clínica como Assunto
20.
Neurologia ; 32(8): 523-532, 2017 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27130306

RESUMO

BACKGROUND: A disease of unknown aetiology, Alzheimer's disease (AD) is the most common type of dementia. As the elderly population grows worldwide, the number of patients with AD also increases rapidly. The aim of this meta-analysis is to evaluate the prevalence and incidence of AD in Europe. METHODOLOGY: We conducted a literature search on Medline, Scopus, and CINAHL Complete using the keywords «Alzheimer¼, «Alzheimer's disease¼, and «AD¼ combined with «prevalence¼, «incidence¼, and «epidemiology¼. A Bayesian random effects model with 95% credible intervals was used. The I2 statistic was applied to assess heterogeneity. RESULTS: The prevalence of Alzheimer's disease in Europe was estimated at 5.05% (95% CI, 4.73-5.39). The prevalence in men was 3.31% (95% CI, 2.85-3.80) and in women, 7.13% (95% CI, 6.56-7.72), and increased with age. The incidence of Alzheimer's disease in Europe was 11.08 per 1000 person-years (95% CI, 10.30-11.89). Broken down by sex, it was 7.02 per 1000 person-years (95% CI, 6.06-8.05) in men and 13.25 per 1000 person-years (95% CI, 12.05-14.51) in women; again these rates increased with age. CONCLUSIONS: The results of our meta-analysis allow a better grasp of the impact of this disease in Europe.


Assuntos
Doença de Alzheimer/epidemiologia , Teorema de Bayes , Europa (Continente)/epidemiologia , Humanos , Incidência , Prevalência
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