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Lyme disease transmission dynamics in the northeastern United States vary by context. Periurban regions, including Block Island, RI, have experienced decades of endemic transmission. In urban areas, including Staten Island, a borough in New York City, NY, Lyme disease is an emerging issue. Knowledge, attitudes, and practices around Lyme disease evolve as an area progresses from emergent to endemic. We conducted focus group discussions and household surveys within Staten Island, NY and Block Island, RI to compare knowledge, attitudes, and practices surrounding Lyme disease and other tick-borne diseases. Qualitative data were coded into themes, and survey data were used to provide more general context of the focus group discussions. Using item response theory, we developed an index of knowledge from relevant factors within the household survey. We identified a significant difference in knowledge scores between the two study areas. Additionally, we identified key differences across multiple domains. Participants from Block Island were more likely to report prior tick exposure and Lyme disease in themselves or household members and were more likely to express concerns about the environmental impact of mitigation strategies. Individuals on Staten Island were more likely to assign responsibility of prevention and control to local, state, and federal government than to take personal prevention measures. Prevention of Lyme disease and other tick-borne diseases must be tailored to the community context and monitored over time as perceptions and priorities may evolve as transmission dynamics transition from emergent to endemic.
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While data show improvement in terms of educational access, dropout rates are significant in many countries. In Spain, 28% of students drop out of school without finishing secondary school, more than double the EU average. Thus, extensive research has shown the consequences of the dropout phenomenon, including negative effects on employment, welfare dependency, as well as health and emotional problems. The transition from primary to secondary education is a critical turning point. This situation worsens in the case of refugee and migrant minors who are refugees or with migrant backgrounds. Although there is strong evidence revealing the potential of SEAs to advance educational success for all in different contexts, no research has yet explored the effect of SEAs on enabling a successful transition from primary to secondary education, which could considerably impact decreasing dropout rates. Drawing on a qualitative case study of a secondary educational centre in Spain, this study analyses the impact of the implementation of three SEAs in key aspects related to primary-secondary transitions. Findings show how the systematic implementation of SEAs impacts the ease of the primary-secondary transition: positive relationships between the educational community are promoted, school connectedness across transition is strengthened, and academic support networks are enhanced. The study therefore suggests the benefits of SEAs as strategies that can enhance positive primary-secondary school transitions in terms of students' perception of belongingness, and academic performance.
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Instituciones Académicas , Humanos , España , Adolescente , Masculino , Femenino , Niño , Estudiantes/psicología , Abandono Escolar/psicología , Refugiados/psicologíaRESUMEN
The introduction of invasive fish species to aquatic ecosystems has been demonstrated to cause disastrous ecological effects. Current conservation strategies regard rotenone-containing piscicide formulations, such as commercial product CFT Legumine, as a potentially viable alternative to the cumbersome traditional approaches to fish eradication. This consideration relies on the fast degradation of rotenone and its relatively rapid dissipation from the environment. Piscicide treatments in fragile aquatic ecosystems should thus monitor not only rotenone concentrations following application, but also other byproducts and degradation products. We present a methodology for the analysis of rotenoids in fresh and brackish waters that addresses two main challenges: the accurate determination of applied concentrations in different salinity concentrations by performing a simplified on-site solid-phase extraction, overcoming the fast degradation of rotenone in sample storage conditions, and the selective analysis of rotenoid byproducts and degradation products by gas chromatography coupled to mass spectrometry. Limits of quantification were below the ecological no-effect concentration of rotenone (2 µg/L) and average recoveries exceeded 80%. Accuracy (compared to expected values) and precision (deviation of replicates) ranged from 78 to 103% and 3 to 14%, respectively, across various rotenoid concentrations. These metrics are more than satisfactory for the intended application of this simplified procedure. The method was applied to piscicide-treated samples, revealing significant and fast degradation of parent rotenoids in storage conditions, as well as a non-negligible accumulation of rotenone in the particulate fraction of water that could impact the effectivity of eradication efforts.
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Peces , Cromatografía de Gases y Espectrometría de Masas , Rotenona , Extracción en Fase Sólida , Contaminantes Químicos del Agua , Rotenona/análisis , Rotenona/química , Animales , Cromatografía de Gases y Espectrometría de Masas/métodos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Extracción en Fase Sólida/métodos , Aguas Salinas/química , Agua Dulce/química , Límite de Detección , Monitoreo del Ambiente/métodos , Reproducibilidad de los ResultadosRESUMEN
Understanding the chemical composition of volatile organic compounds (VOCs) near emission sources and in the background atmosphere above the mixing layer height (MLH) provides insight into the fate of VOCs and is essential for developing effective air pollution control strategies. Unfortunately, knowledge of the qualitative and quantitative changes of VOCs and their vertical transport in the atmosphere is limited due to challenging experimental setups. In this study, an innovative method using tethered balloons was tested and implemented to sample 40 VOCs and O3 below and above the MLH at an industrial site in Spain. VOC and O3 samples were collected with different types of sorbent cartridges and analyzed using chromatographic techniques. Overall, a decrease in VOC concentration with altitude was observed along with a homogeneous chemical composition up to 300 m AGL. This decrease with altitude denoted the primary origin of these VOCs, which were strongly influenced by industrial processes and the traffic emissions in the area. Conversely, O3 concentrations were notably higher at balloon level and increased during nighttime temperature inversion episodes in those samples collected above the mixing layer. Ground samples contained freshly emitted pollutants of industrial origin, while balloon samples consisted of aged pollutants from traffic, other combustion sources, or from a secondary origin. This study is the first to assess the vertical composition of VOCs at a site of these characteristics and demonstrates that tethered balloons are a cost-effective method for studying air pollution dynamics from the ground to higher altitudes in the low troposphere.
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SNAPSHOT USA is a multicontributor, long-term camera trap survey designed to survey mammals across the United States. Participants are recruited through community networks and directly through a website application (https://www.snapshot-usa.org/). The growing Snapshot dataset is useful, for example, for tracking wildlife population responses to land use, land cover, and climate changes across spatial and temporal scales. Here we present the SNAPSHOT USA 2021 dataset, the third national camera trap survey across the US. Data were collected across 109 camera trap arrays and included 1711 camera sites. The total effort equaled 71,519 camera trap nights and resulted in 172,507 sequences of animal observations. Sampling effort varied among camera trap arrays, with a minimum of 126 camera trap nights, a maximum of 3355 nights, a median 546 nights, and a mean 656 ± 431 nights. This third dataset comprises 51 camera trap arrays that were surveyed during 2019, 2020, and 2021, along with 71 camera trap arrays that were surveyed in 2020 and 2021. All raw data and accompanying metadata are stored on Wildlife Insights (https://www.wildlifeinsights.org/), and are publicly available upon acceptance of the data papers. SNAPSHOT USA aims to sample multiple ecoregions in the United States with adequate representation of each ecoregion according to its relative size. Currently, the relative density of camera trap arrays varies by an order of magnitude for the various ecoregions (0.22-5.9 arrays per 100,000 km2), emphasizing the need to increase sampling effort by further recruiting and retaining contributors. There are no copyright restrictions on these data. We request that authors cite this paper when using these data, or a subset of these data, for publication. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the US Government.
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Fotograbar , Estados Unidos , Animales , Mamíferos , EcosistemaRESUMEN
BACKGROUND: human adenovirus (hAdV) infection constitutes an important cause of morbidity and mortality in transplant recipients, due to their immune status. Among drugs currently available, cidofovir (CDF) is the most prescribed. METHODS: Retrospective study of hAdV infection in paediatric transplant recipients from a tertiary paediatric centre, describing characteristics, management, and outcomes, and focused on the role of CDF. RESULTS: 49 episodes of infection by hAdV were detected during a four-year period: 38 episodes in patients that received allogeneic hematopoietic stem cell transplantation (77.6%) and 11 in solid organ transplant recipients (22.4%). Twenty-five patients (52.1%) were symptomatic, presenting mainly fever and/or diarrhoea. CDF was prescribed in 24 patients (49%), with modest results. CDF use was associated with the presence of symptoms resulting in lower lymphocyte count, paediatric intensive care unit admission, and high viral load. Other therapeutic measures included administration of intravenous immunoglobulin, reducing immunosuppression, and T-lymphocyte infusion. Despite treatment, 22.9% of patients did not resolve the infection and there were three deaths related to hAdV infection. All-cause mortality was 16.7% (8 episodes) by 30 days, and 32.7% (16 episodes) by 90 days, of which, 3 episodes (3/16, 18.8%) were attributed to hAdV directly. CONCLUSIONS: hAdV infection had high morbidity and mortality in our series. CDF use is controversial, and available therapeutic options are limited. Transplant patients with low lymphocyte count are at higher risk of persistent positive viremias, and short-term survival of these patients was influenced by the resolution of hAdV infection.
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Objetivo: Analizar la percepción de las enfermeras renales en España en relación con el entorno organizacional para la práctica clínica basada en la evidencia (PCBE); y determinar qué factores profesionales y del contexto influyen en esta percepción. Material y Método: Estudio observacional transversal multicéntrico, en 15 servicios de nefrología de distintos hospitales en España y 2 centros de diálisis. Se utilizaron los instrumentos Practice Environment Scale of Nursing Work Index (PES-NWI) y Evidence Based Practice Questionnarie (EBPQ). Se realizó un análisis estadístico descriptivo, bivariado (ANOVA, Kruskall-Wallis), y regresión logística con la puntuación total del EBPQ como variable dependiente.Resultados: Se recibieron 397 encuestas (participación 84,28%), tras depuración encuestas, fueron válidas 382 (81,1% población): 82,7% mujeres, edad media 42 años, media de experiencia profesional como enfermera 18,2 años (12,2 años en nefrología), 94,8% clínicas, 81,9% de hemodiálisis. Puntuación media PES-NWI 62,35±15,10 (IC 95%: 60,78-48,06). Presentaron menores puntuaciones en algunos factores del PES-NWI las enfermeras de centros >500 enfermeras, que trabajan en hemodiálisis y >11 años de experien-cia profesional. Las enfermeras gestoras presentaron mayores puntuaciones en todos los factores del PES-NWI. Puntuación media EBPQ 81,05±21,92 (IC 95%: 78,70-83,4). Presentaron mayores puntuaciones en varios factores del EBPQ las enfermeras con menor experiencia profesional, mejor puntuación en PES-NWI y que poseían estudios de postgrado.Conclusiones: Los factores que más influyen en la percepción de las enfermeras renales en España son la experiencia profesional, el rol dentro de la organización, un contexto favorable y la formación de postgrado.(AU)
Objective: To analyze the perception of renal nurses in Spain regarding the organizational environment for evidence-based clinical practice (EBCP), and to determine what professional and context factors influence such perception.Material and Method: A crosssectional observational multicenter study was carried out in 15 nephrology services from different Spanish hospitals and 2 dialysis centers. The Practice Environment Scale of Nursing Work Index (PES-NWI) and Evidence-Based Practice Questionnaire (EBPQ) tools were used. A descriptive, bivariate statistical analysis (ANOVA, Kruskall-Wallis) and logistic regression were performed with the EBPQ total score as the dependent variable.Results: A total of 397 surveys were received (participation rate: 84.28%), and after processing the surveys 382 were valid (81.1% of the population): 82.7% were women, with a mean age of 42 years, a mean of 18.2 years of professional experience as a nurse (12.2 years in nephrology), 94.8% were clinical nurses, and 81.9% worked in hemodialysis. The average PES-NWI score was 62.35±15.10 (95% CI:60.78-48.06). Nurses in centers with more than 500 nurses, those who worked in hemodialysis, and those with more than 11 years of professional experience had lower scores on some PES-NWI factors. Nurse managers had higher scores in all PES-NWI factors. The average EBPQ score was 81.05±21.92 (95% CI:78.70-83.4). Nurses with less professional experience the better PES-NWI scores; also, postgraduate nurses had higher scores on several EBPQ factors. Conclusions: Factors that most influence the perception of Spanish renal nurses are professional experience, role within the organization, a favorable context, and postgraduate education.(AU)
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Humanos , Masculino , Femenino , Adulto , Enfermería en Nefrología , Enfermeras y Enfermeros , Práctica Clínica Basada en la Evidencia , Rol de la Enfermera , Atención Hospitalaria , Diálisis , España , Nefrología , Estudios TransversalesRESUMEN
Monoallelic NLRC4 gain-of-function variants cause an inflammasomopathy with diverse clinical forms including infantile enterocolitis, recurrent macrophage activation syndrome, cold-induced urticaria-like lesions (or familial-cold autoinflammatory syndrome, FCAS4), and painful subcutaneous nodules. Here, we identified a large family with six consecutive generations affected. Genetic analyses detected the heterozygous p.Ser445Pro NLRC4 variant in three patients, which has been previously reported in a Dutch family with FCAS4. We aimed to describe the clinicopathological features and the functional consequences of the detected NLRC4 variant. Patients presented an early-onset (3 months-6 years) inflammatory disease characterized by recurrent panniculitis, fever and arthralgia. Histopathological examination showed perivascular and interstitial lymphohistiocytic infiltrates in the dermis and mixed panniculitis. Functional analysis supported the conclusion that the p.Ser445Pro NLRC4 variant leads to a constitutive activation of NLRC4-inflammasome and increased plasma levels of IL-18. Prompt recognition of early-onset panniculitis through clinicopathological examination and laboratory biomarkers may allow targeted therapies.
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Proteínas Adaptadoras de Señalización CARD , Paniculitis , Humanos , Virulencia , Proteínas Adaptadoras de Señalización CARD/genética , Síndrome , Paniculitis/genética , Fenotipo , Proteínas de Unión al Calcio/genéticaRESUMEN
The concentrations of legacy and currently emitted organic pollutants were determined in the freely dissolved phase of water from six high-mountain lakes in the Pyrenees (1619-2453 m) by passive water sampling. Low-density polyethylene (LDPE) and silicone rubber (SR) sheets were exposed for three consecutive periods lasting each one year between 2017 and 2020 for the study of polychlorinated biphenyls (PCBs), organophosphate esters (OPEs), polycyclic aromatic hydrocarbons (PAHs), and other organochlorine compounds (e.g., hexachlorobenzene, HCB). HCB concentrations (1.0-14 pg L-1) remained essentially the same as those measured with pumping systems over two decades ago in the same area. Æ©PAHs (35-920 pg L-1) were around half of those observed in the past, which agrees with reductions in European atmospheric emissions. Æ©PCB concentrations (1.2-2.2 pg L-1) were substantially lower, although unexpectedly large differences could be due to comparing yearly averages from the present study to seasonally variable (i.e., affected by snowmelt, stratification, and colloidal organic matter) episodic pumping measurements from previous studies. Æ©OPEs (139-2849 pg L-1) were measured for the first time in this area and were found at high concentrations in some sites. Concentrations of most compounds obtained with LDPE and SR samplers agreed with each other by ratios generally lower than three or four times, except for a few PAHs and OPEs. Diffusive exchange flux calculations between the atmospheric gas phase and the freely dissolved water phase revealed net deposition of pollutants from air to water, except for some OPEs and PCBs presenting equilibrium conditions, and HCB with volatilization fluxes. Atmospheric degradation fluxes of PAHs and OPEs pointed at competing removal mechanisms that support the air-to-water direction of their diffusive exchange, while PCBs and organochlorines were not affected by photodegradation. In their current state, these remote lakes accumulate many emerging and legacy pollutants subject to long-range atmospheric transport.
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Contaminantes Atmosféricos , Contaminantes Ambientales , Hidrocarburos Clorados , Bifenilos Policlorados , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Contaminantes Ambientales/análisis , Bifenilos Policlorados/análisis , Agua , Hexaclorobenceno/análisis , Lagos , Polietileno , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Hidrocarburos Policíclicos Aromáticos/análisisRESUMEN
Purpose of Review: Preparing for pandemics requires a degree of interdisciplinary work that is challenging under the current paradigm. This review summarizes the challenges faced by the field of pandemic science and proposes how to address them. Recent Findings: The structure of current siloed systems of research organizations hinders effective interdisciplinary pandemic research. Moreover, effective pandemic preparedness requires stakeholders in public policy and health to interact and integrate new findings rapidly, relying on a robust, responsive, and productive research domain. Neither of these requirements are well supported under the current system. Summary: We propose a new paradigm for pandemic preparedness wherein interdisciplinary research and close collaboration with public policy and health practitioners can improve our ability to prevent, detect, and treat pandemics through tighter integration among domains, rapid and accurate integration, and translation of science to public policy, outreach and education, and improved venues and incentives for sustainable and robust interdisciplinary work.
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[This corrects the article DOI: 10.3389/fmolb.2020.592747.].
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BACKGROUND: Public green spaces are important for human health, but they may expose visitors to ticks and tick-borne pathogens. We sought to understand, for the first time, visitors' exposure risk and drivers of tick-preventative behavior in three popular parks on Staten Island, New York City, NY, USA, by integrating tick hazard and park visitors' behaviors, risk perceptions and knowledge. METHODS: We conducted tick sampling in three parks, across three site types (open spaces, the edge of open spaces, and trails) and three within-park habitats (maintained grass, unmaintained herbaceous, and leaf litter) to estimate tick density during May-August 2019. Human behavior was assessed by observations of time spent and activity type in each site. We integrated the time spent in each location by park visitors and the tick density to estimate the probability of human-tick encounter. To assess visitors' tick prevention behaviors, a knowledge, attitude, and practices (KAP) survey was administered. RESULTS: Three tick species (Ixodes scapularis, Amblyomma americanum and Haemaphysalis longicornis) were collected. For all species, the density of nymphs was greatest in unmaintained herbaceous habitats and trails, however, the fewest people entered these hazardous locations. The KAP survey revealed that most respondents (N = 190) identified parks as the main location for tick exposure, but most believed they had minimal risk for tick encounter. Consequently, many visitors did not conduct tick checks. People were most likely to practice tick checks if they knew multiple prevention methods and perceived a high likelihood of tick encounter. CONCLUSIONS: By integrating acarological indices with park visitor behaviors, we found a mismatch between areas with higher tick densities and areas more frequently used by park visitors. However, this exposure risk varied among demographic groups, the type of activities and parks, with a higher probability of human-tick encounters in trails compared to open spaces. Furthermore, we showed that people's KAP did not change across parks even if parks represented different exposure risks. Our research is a first step towards identifying visitor risk, attitudes, and practices that could be targeted by optimized messaging strategies for tick bite prevention among park visitors.
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Ixodes , Enfermedad de Lyme , Mordeduras de Garrapatas , Animales , Humanos , Ciudad de Nueva York/epidemiología , Parques Recreativos , Mordeduras de Garrapatas/epidemiología , Mordeduras de Garrapatas/prevención & controlRESUMEN
Semivolatile organic pollutants have potential for long range atmospheric transport and can thus reach pristine remote lakes by atmospheric deposition. Polycyclic aromatic hydrocarbons (PAHs) are among the most abundant and toxic semivolatile pollutants affecting lakes, however, the main factors controlling their fate are still poorly known. Here we show two contrasting lines of evidence for the importance of microbial degradation on the environmental fate of PAHs in a high altitude deep lake. The first evidence is given by an assessment of the metagenomes from surface and deep waters from Lake Redon (Pyrenees Mountains), which shows the occurrence of the initial ring hydroxylating dioxygenases as well as other PAH degrading genes from the complete metabolic route of PAH degradation. The second line of evidence is by the application of an environmental fate model for PAHs to Lake Redon under two contrasting scenarios considering the inclusion or not of degradation. When degradation is included in the model, PAH concentrations in the sediment are predicted within a factor of two of those measured in Lake Redon. Finally, the extent of the degradation sink is quantified and compared to other cycling PAH fluxes in the lake.
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Contaminantes Ambientales , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Altitud , Monitoreo del Ambiente , Sedimentos Geológicos , Lagos/análisis , Metagenoma , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
The atmospheric gas-phase concentrations of several polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), hexachlorobenzene (HCB), and pentachlorobenzene (PeCB) were measured in six high-mountain sites in the Pyrenees (1619-2453 m). Polyurethane foam passive air samplers were used for this purpose, providing continuous records spanning over three years (2017-2020). The mean concentrations of ∑PCBs, HCB, and PeCB, 13 ± 4 pg m-3, 44 ± 18 pg m-3, and 23 ± 20 pg m-3, respectively, were of the order of those reported in other mountain sites and similar to those measured 20 years ago in the same area, evidencing the persistence of these compounds despite the international regulatory actions. The mean concentration of ∑PAHs was 631 ± 238 pg m-3, representing between two- and three-times lower values than 20 years ago in the same area, but still in the range of other mountain regions. Statistically significant increases in gas-phase concentrations at higher temperatures were observed for most compounds. The experimental phase-change pseudo-enthalpies calculated from the slopes of the regressions between the natural logarithm of the concentrations and the reciprocal of temperature were lower than the reference values for nearly all compounds. This difference suggested a main contribution of long-range atmospheric transport of the gas-phase PAH and organochlorine concentrations in this mountain area. However, the less volatile compounds such as benz[a]anthracene, PCB138, and PCB180 showed a closer similarity between experimental and laboratory enthalpies, indicating that a significant portion of the variations in concentration of these compounds originated from temperature-dependent diffusive exchange by re-volatilization from local surfaces. The concentrations found in these sentinel ecosystems demonstrate that long-range transport of organic pollutants remains a risk in remote continental environments.
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Contaminantes Atmosféricos , Hidrocarburos Clorados , Bifenilos Policlorados , Hidrocarburos Policíclicos Aromáticos , Contaminantes Atmosféricos/análisis , Ecosistema , Monitoreo del Ambiente , Hexaclorobenceno/análisis , Hidrocarburos Clorados/análisis , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisisRESUMEN
The air concentrations of organophosphate esters (OPEs) were studied in a network of six remote high-mountain areas of the Pyrenees located along an altitudinal profile between 1619 m and 2453 m above sea level on a restricted planar surface to assess their vertical distribution based on long-range atmospheric transport and temperature gradients. Polyurethane foam passive samplers were used in five periods spanning over three years (September 2017-October 2020). The sum of concentrations of five OPEs were between 5.3 and 100 pg m-3, averaging 16-53 pg m-3 across campaigns at the different locations. These concentrations were much lower than those observed in areas under anthropogenic influence but also than those found in low altitude remote continental sites. A significant progressive change in predominant compounds was observed along the altitudinal gradient, with prevalence of tris(1-chloro-2-propyl) phosphate (TCIPP) or tris(2-chloroethyl) phosphate (TCEP) below or above 2300 m above sea level, respectively. This trend was consistent with the higher volatility of TCEP, which was retained at greater extent at lower environmental temperatures (higher altitude). A significant temperature dependence of the gas phase concentrations was observed for TCEP, TCIPP and triphenyl phosphate (TPHP), which could be explained by retention in the cold periods, predominantly adsorbed in snow, and their release to the atmosphere during snowmelt. This mechanism was consistent with the good agreement found between the vaporization enthalpies measured under laboratory conditions and the experimental values obtained from the slopes of the significant linear regressions when representing the vertical gradients.
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Retardadores de Llama , Monitoreo del Ambiente , Ésteres , Retardadores de Llama/análisis , Organofosfatos , TemperaturaRESUMEN
Centrosomes are the main microtubule-organizing centres, playing essential roles in the organization of the cytoskeleton during interphase, and in the mitotic spindle, which controls chromosome segregation, during cell division. Centrosomes also act as the basal body of cilia, regulating cilium length and affecting extracellular signal reception as well as the integration of intracellular signalling pathways. Centrosomes are self-replicative and duplicate once every cell cycle to generate two centrosomes. The core support structure of the centrosome consists of two molecularly distinct centrioles. The mother (mature) centriole exhibits accessory appendages and is surrounded by both pericentriolar material and centriolar satellites, structures that the daughter (immature) centriole lacks. In this Review, we discuss what is currently known about centrosome duplication, its dialogue with the cell cycle and the sequential acquisition of specific components during centriole maturation. We also describe our current understanding of the mature centriolar structures that are required to build a cilium. Altogether, the built-in centrosome asymmetries that stem from the two centrosomes inheriting molecularly different centrioles sets the foundation for cell division being an intrinsically asymmetric process.
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Centriolos , Centrosoma , Ciclo Celular , División Celular , CiliosRESUMEN
Polyurethane foam passive air samplers (PUF-PAS) are good candidates for the determination of gas-phase semi-volatile organic compound (SVOC) air concentrations in high-mountain areas over long periods because they do not require an energy supply. However, the harsh meteorological conditions present in such locations can increase the uncertainties inherently associated to PAS sampling rates due to the many variables involved in their calculation and to the assumptions made regarding PUF diffusive uptake mechanics, which can considerably bias the resulting concentrations. Therefore, we studied the performance of PUF-PASs in a remote location in the Pyrenees mountain range for the analysis of several SVOCs in air, including polychlorobiphenyls (PCBs), hexachlorobenzene, pentachlorobenzene, polycyclic aromatic hydrocarbons (PAHs), and the less studied emerging organophosphate flame retardants (OPFRs). An in-situ PUF-PAS calibration using Performance Reference Compounds (PRCs) provided compound- and sampler-specific sampling rates, showing mean experimental errors (12%) that adequately conformed to an estimate of their expanded theoretical uncertainties (15%). This showcases the suitability of this calibration strategy in an area with conditions beyond those typically considered in calibration efforts available to date. Moreover, gas-phase concentrations of the studied pollutants from PUF-PAS samples showed very good agreement (R2 up to 0.91, p < 0.01) when compared to those obtained using a conventional high-volume active air sampler (PUF-AAS), with some minor deviations observed for PAHs caused by the seasonality in their atmospheric concentrations. No relevant levels of pollutants preferentially bound to the particle phase were detected in the PUF-PASs, the particle infiltration efficiency of the sampler configuration used was found to be low, and compounds typically distributed between the gas and particle phases of AAS samples revealed profiles consistent with their vapor pressures, except for some OPFRs.