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1.
J Anim Ecol ; 93(6): 715-730, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38529896

RESUMO

Ecological processes that are behind distributions of species that inhabit isolated localities, complex disjunct distributions, remain poorly understood. Traditionally, vicariance and dispersion have been proposed as explanatory mechanisms that drive such distributions. However, to date, our understanding of the ecological processes driving evolution of ecological niches associated with disjunct distributions remains rudimentary. Here, we propose a framework to deconstruct drivers of such distribution using World's most widespread freshwater fish Galaxias maculatus as a model and integrating marine and freshwater environments where its life cycle may occur. Specifically, we assessed ecological and historical factors (Gondwanan vicariance, marine dispersion) and potential dispersion (niche-tracking) that explain its distribution in the Southern Hemisphere. Estimated distribution was consistent with previously reported distribution and mainly driven by temperature and topography in freshwater environments and by primary productivity and nitrate in marine environments. Niche dynamics of G. maculatus provided evidence of synergy between vicariance and marine dispersion as explanatory mechanisms of its disjunct distribution, suggesting that its ecological niche was conserved since approximately 30 Ma ago. This integrated assessment of ecological niche in marine and freshwater environments serves as a generic framework that may be applied to understand processes underpinning complex distributions of diadromous species.


Los procesos ecológicos que subyacen a las distribuciones de especies que habitan en localidades aisladas, distribuciones disjuntas complejas, siguen siendo poco conocidos. Tradicionalmente, se han propuesto la dispersión y la vicarianza como mecanismos explicativos de tales distribuciones. Sin embargo, hasta la fecha, nuestra comprensión de los procesos ecológicos que impulsan la evolución de los nichos ecológicos de distribuciones disjuntas sigue siendo rudimentaria. Aquí proponemos un marco para de­construir los factores que impulsan dicha distribución, utilizando como modelo el pez de agua dulce con distribución más extendida del mundo, Galaxias maculatus, e integrando los entornos marinos y dulceacuícolas en los que se desarrolla su ciclo vital. En concreto, evaluamos los factores ecológicos e históricos (vicarianza gondwánica, dispersión marina) que explican su distribución en el hemisferio sur. La distribución estimada coincide con la descrita anteriormente para la especie y está determinada principalmente por la temperatura y la topografía en ambientes dulceacuícolas, y la productividad primaria y el nitrato en ambientes marinos. La dinámica de nicho de G. maculatus aportó pruebas de la sinergia entre vicarianza y dispersión marina como mecanismos explicativos de su distribución disjunta, lo que sugiere que su nicho ecológico se conservó desde hace aproximadamente 30 Ma. Esta evaluación integrada del nicho ecológico en ambientes marinos y dulceacuícolas puede aplicarse para comprender los procesos que subyacen a las distribuciones complejas de especies diádromas.


Assuntos
Distribuição Animal , Evolução Biológica , Ecossistema , Água Doce , Animais , Osmeriformes/fisiologia
2.
J Chem Phys ; 160(16)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38661197

RESUMO

The focus of our study is an in-depth investigation of the quantum effects associated with the surface tension and other thermodynamic properties of nanoscopic liquid drops. The behavior of drops of quantum Lennard-Jones fluids is investigated with path-integral Monte Carlo simulations, and the test-area method is used to determine the surface tension of the spherical vapor-liquid interface. As the thermal de Broglie wavelength, λB, becomes more significant, the average density of the liquid drop decreases, with the drop becoming mechanically unstable at large wavelengths. As a consequence, the surface tension is found to decrease monotonically with λB, vanishing altogether for dominant quantum interactions. Quantum effects can be significant, leading to values that are notably lower than the classical thermodynamic limit, particularly for smaller drops. For planar interfaces (with infinite periodicity in the direction parallel to the interface), quantum effects are much less significant with the same values of λB but are, nevertheless, consequential for values representative of hydrogen or helium-4 at low temperatures corresponding to vapor-liquid coexistence. Large quantum effects are found for small drops of molecules with quantum interactions corresponding to water, ethane, methanol, and carbon dioxide, even at ambient conditions. The notable decrease in the density and tension has important consequences in reducing the Gibbs free-energy barrier of a nucleating cluster, enhancing the nucleation kinetics of liquid drops and of bubble formation. This implies that drops would form at a much greater rate than is predicted by classical nucleation theory.

3.
Entropy (Basel) ; 23(6)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207472

RESUMO

We present computer simulation and theoretical results for a system of N Quantum Hard Spheres (QHS) particles of diameter σ and mass m at temperature T, confined between parallel hard walls separated by a distance Hσ, within the range 1≤H≤∞. Semiclassical Monte Carlo computer simulations were performed adapted to a confined space, considering effects in terms of the density of particles ρ*=N/V, where V is the accessible volume, the inverse length H-1 and the de Broglie's thermal wavelength λB=h/2πmkT, where k and h are the Boltzmann's and Planck's constants, respectively. For the case of extreme and maximum confinement, 0.5

4.
BMC Pregnancy Childbirth ; 20(1): 587, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33023500

RESUMO

BACKGROUND: There are no published cases of tonic-clonic seizures and posterior bilateral blindness during pregnancy and Severe Acute Respiratory Syndrome (SARS) Coronavirus (COV) 2 (SARS-COV-2) infection. We do not just face new and unknown manifestations, but also how different patient groups are affected by SARS-COV-2 infection, such as pregnant women. Coronavirus Disease 2019 (COVID-19), preeclampsia, eclampsia and posterior reversible leukoencephalopathy share endothelium damage and similar pathophysiology. CASE PRESENTATION: A 35-year-old pregnant woman was admitted for tonic-clonic seizures and SARS-COV-2 infection. She had a normal pregnancy control and no other symptoms before tonic-clonic seizures development. After a Caesarean section (C-section) she developed high blood pressure, and we initiated antihypertensive treatment with labetalol, amlodipine and captopril. Few hours later she developed symptoms of cortical blindness that resolved in 72 h with normal brain computed tomography (CT) angiography. CONCLUSION: The authors conclude that SARS COV-2 infection could promote brain endothelial damage and facilitate neurological complications during pregnancy.


Assuntos
Anti-Hipertensivos/administração & dosagem , Betacoronavirus/isolamento & purificação , Cegueira Cortical , Cesárea/métodos , Infecções por Coronavirus , Eclampsia , Fibrinolíticos/administração & dosagem , Pandemias , Pneumonia Viral , Complicações Infecciosas na Gravidez , Convulsões , Adulto , Cegueira Cortical/diagnóstico , Cegueira Cortical/virologia , Encéfalo/diagnóstico por imagem , COVID-19 , Angiografia por Tomografia Computadorizada/métodos , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/fisiopatologia , Diagnóstico Diferencial , Eclampsia/diagnóstico , Eclampsia/terapia , Eclampsia/virologia , Feminino , Humanos , Exame Neurológico/métodos , Pneumonia Viral/diagnóstico , Pneumonia Viral/fisiopatologia , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/etiologia , Complicações Infecciosas na Gravidez/fisiopatologia , Resultado da Gravidez , SARS-CoV-2 , Convulsões/diagnóstico , Convulsões/etiologia , Convulsões/terapia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
5.
Proc Natl Acad Sci U S A ; 110(45): 18098-103, 2013 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-24145422

RESUMO

The coupling of subseafloor microbial life to oceanographic and atmospheric conditions is poorly understood. We examined diagenetic imprints and lipid biomarkers of past subseafloor microbial activity to evaluate its response to glacial-interglacial cycles in a sedimentary section drilled on the Peruvian shelf (Ocean Drilling Program Leg 201, Site 1229). Multiple and distinct layers of diagenetic barite and dolomite, i.e., minerals that typically form at the sulfate-methane transition (SMT), occur at much shallower burial depth than the present SMT around 30 meters below seafloor. These shallow layers co-occur with peaks of (13)C-depleted archaeol, a molecular fossil of anaerobic methane-oxidizing Archaea. Present-day, non-steady state distributions of dissolved sulfate also suggest that the SMT is highly sensitive to variations in organic carbon flux to the surface shelf sediments that may lead to shoaling of the SMT. Reaction-transport modeling substantiates our hypothesis that shallow SMTs occur in response to cyclic sediment deposition with a high organic carbon flux during interglacials and a low organic carbon flux during glacial stages. Long diffusion distances expectedly dampen the response of deeply buried microbial communities to changes in sediment deposition and other oceanographic drivers over relatively short geological time scales, e.g., glacial-interglacial periods. However, our study demonstrates how dynamically sediment biogeochemistry of the Peru Margin has responded to glacial-interglacial change and how these changes are now preserved in the geological record. Such changes in subsurface biogeochemical zonation need to be taken into account to assess the role of the subseafloor biosphere in global element and redox cycling.


Assuntos
Sedimentos Geológicos/química , Fenômenos Geológicos , Metano/análise , Modelos Químicos , Oceanografia/métodos , Sulfato de Bário/análise , Biomarcadores/análise , Carbonato de Cálcio/análise , Isótopos de Carbono/análise , Lipídeos/análise , Magnésio/análise , Metano/metabolismo , Oxirredução , Oceano Pacífico , Peru , Fatores de Tempo
6.
Proc Natl Acad Sci U S A ; 110(47): 18994-9, 2013 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-24191043

RESUMO

Nitrogen (N) isotope ratios ((15)N/(14)N) provide integrative constraints on the N inventory of the modern ocean. Anaerobic ammonium oxidation (anammox), which converts ammonium and nitrite to dinitrogen gas (N2) and nitrate, is an important fixed N sink in marine ecosystems. We studied the so far unknown N isotope effects of anammox in batch culture experiments. Anammox preferentially removes (14)N from the ammonium pool with an isotope effect of +23.5‰ to +29.1‰, depending on factors controlling reversibility. The N isotope effects during the conversion of nitrite to N2 and nitrate are (i) inverse kinetic N isotope fractionation associated with the oxidation of nitrite to nitrate (-31.1 ± 3.9‰), (ii) normal kinetic N isotope fractionation during the reduction of nitrite to N2 (+16.0 ± 4.5‰), and (iii) an equilibrium N isotope effect between nitrate and nitrite (-60.5 ± 1.0‰), induced when anammox is exposed to environmental stress, leading to the superposition of N isotope exchange effects upon kinetic N isotope fractionation. Our findings indicate that anammox may be responsible for the unresolved large N isotope offsets between nitrate and nitrite in oceanic oxygen minimum zones. Irrespective of the extent of N isotope exchange between nitrate and nitrite, N removed from the combined nitrite and nitrate (NOx) pool is depleted in (15)N relative to NOx. This net N isotope effect by anammox is superimposed on the N isotope fractionation by the co-occurring reduction of nitrate to nitrite in suboxic waters, possibly enhancing the overall N isotope effect for N loss from oxygen minimum zones.


Assuntos
Compostos de Amônio/metabolismo , Bactérias Anaeróbias/metabolismo , Isótopos de Nitrogênio/metabolismo , Água do Mar/análise , Cinética , Modelos Biológicos , Oceanos e Mares , Água do Mar/microbiologia
7.
Sci Total Environ ; 895: 165065, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37355134

RESUMO

Southern South America is the only large landmass that extends through the core of the Southern Westerly Winds (SWW), controlling hydrological and ecosystem variability in the region. In fact, the vegetation along the west coast changes from Temperate and Valdivian Rain Forest to the North Patagonian Evergreen Forest (ca. 42°S) due to the latitudinal influence of the SWW. Climate is an important driver of organic matter accumulation in lakes, hence changes in vegetation would be recorded in lacustrine sedimentary archives. This study evaluated leaf waxes contained in lake surface sediments as indicators of climate change along the west coast of southern South America, providing a biogeochemical dataset for ongoing and future (paleo)climate and environmental research. The fatty acid and n-alkane sediment leaf wax datasets are compared with latitudinal, orographic, and climatic (Mean Annual air Temperature [MAT] & Precipitation [MAP]) trends extracted from a monthly gridded reanalysis product of the Climate Forecast System Reanalysis. Fatty acids are more abundant than n-alkanes, with high abundances characterizing the transition between seasonal and year-round precipitation along the coast (ca. 42°S). The abundance of both leaf wax groups increases with MAP, suggesting precipitation as the main control on sedimentary leaf wax delivery to the lake sediments in the study area. The Carbon Preference Index (CPI) of the two groups show opposite trends, but both highlight the climate transition at ca. 42°S, and have a linear relationship with MAP. The opposite significant trends between n-alkane CPI and fatty acid CPI with MAP are interpreted as higher n-alkane production at much higher precipitation because leaf wax fatty acids are the precursors of n-alkanes. Hence, past periods during which these leaf waxes show opposite trends in CPI might be interpreted as a precipitation change, especially if additional information such as pollen, diatoms, chironomids and stable isotopes is available.


Assuntos
Alcanos , Lagos , Alcanos/análise , Ceras/química , Ecossistema , Folhas de Planta/química , Ácidos Graxos/análise
8.
Radiat Prot Dosimetry ; 199(18): 2189-2193, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37934983

RESUMO

Environmental radioactivity study was performed in unconventional hydrocarbons areas for the first time in Mexico, where four unconventional hydrocarbon exploratory wells (UHEW) are planned. This study assesses natural radiological conditions in areas around UHEW. Equivalent dose rate distribution displayed in Geographic Information System (GIS) had a maximum of 1.83 mSv a-1 and minimum of 0.04 mSv a-1, GIS was also used for introducing land usage, water resources and population occupancy. Measurements of gross alpha and gross beta in water were below the national permissible limits for drinking water 0.5 and 1.0 Bq L-1 respectively, even though samples do not correspond to drinking water. Evaluation of 238U and 226Ra in groundwater were below minimum detectable concentration 1.3 and 1.0 Bq L-1, respectively. This study provides a radiological baseline for the impact of future industrial activities, especially if exploitation of unconventional hydrocarbons produces naturally occurring radioactive material.


Assuntos
Água Potável , Água Subterrânea , Monitoramento de Radiação , Rádio (Elemento) , Urânio , Poluentes Radioativos da Água , Água Potável/análise , Urânio/análise , Rádio (Elemento)/análise , México , Hidrocarbonetos , Poluentes Radioativos da Água/análise
9.
Plant Cell Environ ; 35(6): 1026-39, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22146000

RESUMO

We investigated whether stand structure modulates the long-term physiological performance and growth of Pinus halepensis Mill. in a semiarid Mediterranean ecosystem. Tree radial growth and carbon and oxygen stable isotope composition of latewood (δ(13)C(LW) and δ(18)O(LW), respectively) from 1967 to 2007 were measured in P. halepensis trees from two sharply contrasting stand types: open woodlands with widely scattered trees versus dense afforested stands. In both stand types, tree radial growth, δ(13)C(LW) and δ(18)O(LW) were strongly correlated with annual rainfall, thus indicating that tree performance in this semiarid environment is largely determined by inter-annual changes in water availability. However, trees in dense afforested stands showed consistently higher δ(18)O(LW) and similar δ(13)C(LW) values compared with those in neighbouring open woodlands, indicating lower stomatal conductance and photosynthesis rates in the former, but little difference in water use efficiency between stand types. Trees in dense afforested stands were more water stressed and showed lower radial growth, overall suggesting greater vulnerability to drought and climate aridification compared with trees in open woodlands. In this semiarid ecosystem, the negative impacts of intense inter-tree competition for water on P. halepensis performance clearly outweigh potential benefits derived from enhanced infiltration and reduced run-off losses in dense afforested stands.


Assuntos
Clima , Secas , Ecossistema , Pinus/crescimento & desenvolvimento , Pinus/fisiologia , Isótopos de Carbono/análise , Região do Mediterrâneo , Isótopos de Oxigênio/análise , Chuva , Espanha , Árvores/crescimento & desenvolvimento , Árvores/fisiologia , Água/fisiologia
10.
Sci Rep ; 12(1): 3164, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35210443

RESUMO

Longitudinal movement plays fundamental role in habitat colonization and population establishment of many riverine fish species. Movement patterns of amphidromous fish species at fine-scales that would allow characterizing the direction of movement and factors associated with the establishment of specific life-history strategies (resident or amphidromous) in rivers are still poorly understood. We assess fine-scale longitudinal movement variability patterns of facultative amphidromous fish species Galaxias maculatus in order to unfold its life-history variation and associated recruitment habitats. Specifically, we analyzed multi-elemental composition along core to edge transects in ear-bones (otoliths) of each fish using recursive partitions that divides the transect along signal discontinuities. Fine-scale movement assessment in five free-flowing river systems allowed us to identify movement direction and potential recruitment habitats. As such, resident recruitment of G. maculatus in freshwater (71%) and estuarine (24%) habitats was more frequent than amphidromous recruitment (5%), and was linked to availability of slow-flowing lotic or lentic habitats that produce or retain small-bodied prey consumed by their larvae. We postulate that life-history variation and successful recruitment of facultative amphidromous fish such as G. maculatus in river systems is driven by availability of suitable recruitment habitats and natural hydrologic connectivity that allows fish movement to these habitats.


Assuntos
Migração Animal , Comportamento Animal , Peixes/fisiologia , Osmeriformes/fisiologia , Animais , Ecossistema , Água Doce , Rios
11.
Arch Bronconeumol ; 58(5): 406-411, 2022 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35312494

RESUMO

INTRODUCTION: Lung cancer (LC) is usually diagnosed at advanced stages with only a 12% 5-year survival. Trials as NLST and NELSON show a mortality decrease, which justifies implementation of lung cancer screening in risk population. Our objective was to show survival results of the largest LC screening program in Spain with low dosage computed tomography (LDCT). METHODS: Clinical records from International Early Lung Cancer Detection Program (IELCAP) at Valencia, Spain were analysed. This program recruited volunteers, ever-smokers aged 40-80 years, since 2008. Results are compared to those from other similar sizeable programs. RESULTS: A total of 8278 participants were screened with at least two-rounds until November 2020. A mean of 6 annual screening rounds were performed. We detected 239 tumours along 12-year follow-up. Adenocarcinoma was the most common histology, being 61.3% at stage I. The lung cancer prevalence and incidence proportion was 1.5% and 1.4%, respectively with an annual detection rate of 0.17. One-year survival and 10-year survival were 90% and 80.1%, respectively. Adherence was 96.84%. CONCLUSION: Largest lung cancer screening in Spain shows that survival is improved when is performed in multidisciplinary team experienced in management of LC, and is comparable to similar screening programs.


Assuntos
Detecção Precoce de Câncer , Neoplasias Pulmonares , Detecção Precoce de Câncer/métodos , Humanos , Pulmão , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/epidemiologia , Programas de Rastreamento , Espanha/epidemiologia , Tomografia Computadorizada por Raios X/métodos
12.
Sci Rep ; 11(1): 8725, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888733

RESUMO

Warming across the globe is expected to alter the strength and amount of regional precipitation, but there is uncertainty associated with the magnitude of these expected changes, and also how these changes in temperature and the hydrologic cycle will affect humans. For example, the climate in central-south Chile is projected to become significantly warmer and drier over the next several decades in response to anthropogenically driven warming, but these anthropogenic changes are superimposed on natural climate variability. The stable isotope composition of meteoric water provides significant information regarding the moisture source, pathways, and rain-out history of an air mass, but precipitation samples suitable for stable isotope measurements require long-term placement of field equipment making them difficult to obtain. The International Atomic Energy Agency (IAEA) Global Network of Isotopes in Precipitation (GNIP) stations generate isotopic and ancillary data of precipitation from many locations around the world, but remote areas of developing countries like Chile typically have sparse networks of meteorological stations, which inhibit our ability to accurately model regional precipitation. Central-south Chile, in particular, has a sparse network of GNIP stations and, as a result, the isotopic composition of meteoric water is underrepresented in the global database complicating efforts to constrain modern day hydroclimate variability as well as paleohydrologic reconstruction for southern South America. In this study, we measured the stable isotope compositions of hydrogen (δ2H) and oxygen (δ18O) in surface lacustrine waters of central-south Chile to determine what physical and/or climatic features are the dominant controls on lacustrine δ18O and δ2H composition, assess whether or not the isotopic composition of the lakes record time-averaged isotope composition of meteoric water, and determine whether an isoscape map based on lake surface waters could predict the H and O isotope compositions of precipitation at the few GNIP stations in the region.

13.
Sci Total Environ ; 760: 143382, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33158525

RESUMO

The spread of coronavirus disease 2019 (COVID-19) on 2020 has affected human activities in a way never documented in modern history. As a consequence of the prevention measures implemented to contain the virus, cities around the world are experiencing a decrease in urban mobility and electricity demand that have positively affected the air quality. The most extreme cases for cities around the world show a decrease of 90, 40, and 70% in mobility, electricity demand, and NO2 emissions respectively. At the same time, the inspection of these changes along the evaluation of COVID-19 incidence curves allow to obtain feedback about the timely execution of prevention measures for this and future global events. In this case, we identify and discuss the early effort of Latin-American countries to successfully delay the spread of the virus by implementing prevention measures before the fast growth of COVID-19 cases in comparison to European countries.


Assuntos
Poluição do Ar , COVID-19 , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , Cidades , Eletricidade , Europa (Continente) , Retroalimentação , Humanos , Dióxido de Nitrogênio/análise , Material Particulado/análise , SARS-CoV-2
14.
Sci Total Environ ; 798: 149241, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34333429

RESUMO

The postglacial Patagonian fjord system along the west coast of southern South America is one of the largest stretches of the southern hemisphere (SH) fjord belt, influenced by the SH westerly wind belt and continental freshwater input. This study reports a 3-year monthly time series (2017-2020) of physical and biogeochemical parameters obtained from the Reloncaví Marine Observatory (OMARE, Spanish acronym) at the northernmost embayment and fjord system of Patagonia. The main objective of this work was to understand the land-atmosphere-ocean interactions and to identify the mechanisms that modulate the density of phytoplankton. A key finding of this study was the seasonally varying asynchronous input of oceanic and estuarine water. Surface lower salinity and warmer estuarine water arrived in late winter to summer, contributing to water column stability, followed by subsurface higher salinity and less warmer oceanic water during fall-winter. In late winter 2019, an interannual change above the picnocline due to the record-high polarity of the Indian Ocean Dipole inhibited water column stability. The biogeochemical parameters (NO3-, NO2-, PO43-, Si(OH)4, pH, and dissolved oxygen) responded to the surface annual salinity variations, and oceanic water mass contributed greatly to the subsurface inorganic nutrient input. The water column N/P ratio indicated that no eutrophication occurred, even under intense aquaculture activity, likely because of the high ventilation dynamics of the Reloncaví Sound. Finally, a shift in phytoplankton composition, characterized by surface chlorophyll-a maxima in late winter and deepening of spring-summer blooms related to the physicochemical conditions of the water column, was observed. Our results support the ecosystem services provided by local oceanography processes in the north Patagonian fjords. Here, the anthropogenic impact caused by economic activities could be, in part, chemically reduced by the annual ventilation cycle mediated by the exchange of oceanic water masses into Patagonian fjords.


Assuntos
Ecossistema , Estuários , Monitoramento Ambiental , Oceano Índico , Oceanografia , Fitoplâncton , Água do Mar
15.
Sci Total Environ ; 663: 901-914, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30738269

RESUMO

The Mar Menor is the largest lagoon along the Spanish Mediterranean coast. It suffers from eutrophication and algal blooms associated with intensive agricultural activities and urban pressure in the surrounding Campo de Cartagena plain. A balanced discharge of groundwater, carrier of algal nutrients such as nitrate, is essential to ensure the integrity of the coastal lagoon and the availability of groundwater resources inland. We here present a 3D hydrogeological model of the unconfined Quaternary aquifer that discharges into the lagoon. The model couples both surface water balance and groundwater dynamics and has been calibrated to available data in the period 2000-2016. The calibrated model allows understanding of the current state of the aquifer and its link to the lagoon. The potential discharge has been quantified in both space and time and falls between 69.5 and 84.9 hm3/yr during dry and wet periods, respectively (with values of nitrate discharge of 11.4-11.8 Mkg/yr in the absence of aquifer sink terms, e.g., leakage to deeper aquifers and pumping from groundwater wells). The predictive capabilities of the calibrated model can be used to test the impact of different integrated management scenarios on the surface-groundwater dynamics of the catchment. Three plausible management scenarios are proposed that include localized and distributed groundwater pumping (drains and groundwater wells, respectively). Results show the effectiveness of the scenarios in reducing the groundwater and nitrate discharge into the lagoon. The disadvantages of the proposed scenarios, including potential seawater intrusion, need to be balanced with their relative merits for the sustainable development of the region and the survival of the Mar Menor ecosystem. The modelling approach proposed provides a valuable tool for the integrated and holistic management of the Campo de Cartagena-Mar Menor catchment and should be of great interest to similar hydrological systems with high ecological value.

16.
Mar Pollut Bull ; 126: 389-395, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29421116

RESUMO

Surface water samples from the environmental continuum spanning rivers (Petrohue, Cochamo, Puelo), fjord (Reloncaví), and the inner sea of Chiloé in Chilean Patagonia were analyzed to estimate concentration and distribution of dissolved Organochlorine pesticides (OCPs). High concentrations of HCHs, DDTs and endosulfan found in surface waters from rivers suggest that rivers are the major source of dissolved OCPs to coastal marine ecosystems. We interpret variations in the distribution and concentration as an apparent oscillation between rain and snow-scavenging processes that might determine the type of OCPs that can be preferentially deposited on mountains, glaciers, rivers, estuaries, and finally transferred to the marine realm. Predominance of α-HCH, γ-HCH, p,p'-DDE and α-endosulfan compounds suggest that the main deposition mechanism of OCPs to the Chilean Patagonia is rain scavenging. Snow and rain can be additional sources of OCPs that must be considered for future studies in fjord systems in Chilean Patagonia.


Assuntos
Endossulfano/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes Químicos da Água/análise , Chile , Monitoramento Ambiental , Estuários , Chuva , Rios , Neve
17.
Sci Total Environ ; 630: 878-888, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29499543

RESUMO

Paleolimnological studies in western South America, where meteorological stations are scarce, are critical to obtain more realistic and reliable regional reconstructions of past climate and environmental changes, including vegetation and water budget variability. However, climate and environmental geochemical indicators must be tested before they can be applied with confidence. Here we present a survey of lacustrine surface sediment (core top, 0 to ~1cm) biogeochemical proxies (total organic carbon [TOC], total nitrogen [TN], carbon/nitrogen ratio [C/N ratio] and bulk organic δ13C and total δ15N) from a suite of 72 lakes spanning the transition from a Mediterranean climate with a patchwork of cultivated vegetation, pastureland, and conifers in central Chile to a rainy temperate climate dominated by broadleaf deciduous and evergreen forest further south. Sedimentary data are compared to the latitudinal and orographic climatic trends of the region based on the climatology (precipitation and temperature) produced with Climate Forecast System Reanalysis (CFSR) data and the modern Southern Hemisphere Westerly Winds (SWW) location. The geochemical data show inflection points at ~42°S latitude and ~1500m elevation that are likely related to the northern limit of influence of the SWW and elevation of the snow line, respectively. Overall the organic proxies were able to mimic climatic trends (Mean Annual Precipitation [MAP] and temperature [MAT]), indicating that they are a useful tool to be included in paleoclimatological reconstruction of the region.

18.
Arch. bronconeumol. (Ed. impr.) ; 58(5): 406-411, Mayo 2022. ilus, tab, graf
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-206574

RESUMO

Introducción y objetivo: El cáncer de pulmón (CP) se diagnostica habitualmente en estadios avanzados con una supervivencia media a cinco años del 12%. Ensayos como el National Lung Screening Trial (NLST) y el NEderlands Leuvens longkanker Screenings ONderzoek (NELSON) demuestran una reducción de la mortalidad que justifican la implantación del cribado en población de riesgo. Nuestro objetivo es presentar los resultados de supervivencia del programa de cribado de CP más amplio de España con tomografía computarizada de baja dosis (TCBD). Métodos: Se analizaron los datos del programa Internacional de Detección Precoz de CP (IELCAP) en Valencia, España. Este programa reclutó fumadores o exfumadores con una edad entre 40- 80 años. Se comparan los resultados con otros programas de similar tamaño. Resultados: Un total de 8.278 participantes fueron reclutados con al menos dos rondas de seguimiento, hasta noviembre de 2020 (62,8% varones), realizando una media de seis rondas de cribado por individuo. Diagnosticamos 239 tumores en 12 años de seguimiento. El adenocarcinoma fue el tumor más frecuente con un 61,3% en estadio I. Las tasas de prevalencia e incidencia fueron de 1,5% y 1,4%, respectivamente, con una tasa de detección anual de 0,17. Las tasas de supervivencia cáncer específica a cinco años fueron del 90 y del 80,1% a 10 años. La adherencia fue de 96,84%. Conclusión: La experiencia del programa más amplio de España demuestra que la supervivencia se mejora cuando se realiza en equipos multidisciplinares con experiencia en CP y es similar a programas similares. (AU)


Introduction: Lung cancer (LC) is usually diagnosed at advanced stages with only a 12% 5-year survival. Trials as NLST and NELSON show a mortality decrease, which justifies implementation of lung cancer screening in risk population. Our objective was to show survival results of the largest LC screening program in Spain with low dosage computed tomography (LDCT). Methods: Clinical records from International Early Lung Cancer Detection Program (IELCAP) at Valencia, Spain were analysed. This program recruited volunteers, ever-smokers aged 40-80 years, since 2008. Results are compared to those from other similar sizeable programs. Results: A total of 8278 participants were screened with at least two-rounds until November 2020. A mean of 6 annual screening rounds were performed. We detected 239 tumours along 12-year follow-up. Adenocarcinoma was the most common histology, being 61.3% at stage I. The lung cancer prevalence and incidence proportion was 1.5% and 1.4%, respectively with an annual detection rate of 0.17. One-year survival and 10-year survival were 90% and 80.1%, respectively. Adherence was 96.84%. Conclusion: Largest lung cancer screening in Spain shows that survival is improved when is performed in multidisciplinary team experienced in management of LC, and is comparable to similar screening programs. (AU)


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Programas de Rastreamento , Detecção Precoce de Câncer , Espanha , Fumantes , Ex-Fumantes
19.
Arch. bronconeumol. (Ed. impr.) ; 58(5): t406-t411, Mayo 2022. ilus, tab
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-206575

RESUMO

Introduction: Lung cancer (LC) is usually diagnosed at advanced stages with only a 12% 5-year survival. Trials as NLST and NELSON show a mortality decrease, which justifies implementation of lung cancer screening in risk population. Our objective was to show survival results of the largest LC screening program in Spain with low dosage computed tomography (LDCT). Methods: Clinical records from International Early Lung Cancer Detection Program (IELCAP) at Valencia, Spain were analysed. This program recruited volunteers, ever-smokers aged 40-80 years, since 2008. Results are compared to those from other similar sizeable programs. Results: A total of 8278 participants were screened with at least two-rounds until November 2020. A mean of 6 annual screening rounds were performed. We detected 239 tumours along 12-year follow-up. Adenocarcinoma was the most common histology, being 61.3% at stage I. The lung cancer prevalence and incidence proportion was 1.5% and 1.4%, respectively with an annual detection rate of 0.17. One-year survival and 10-year survival were 90% and 80.1%, respectively. Adherence was 96.84%. Conclusion: Largest lung cancer screening in Spain shows that survival is improved when is performed in multidisciplinary team experienced in management of LC, and is comparable to similar screening programs. (AU)


Introducción y objetivo: El cáncer de pulmón (CP) se diagnostica habitualmente en estadios avanzados con una supervivencia media a cinco años del 12%. Ensayos como el National Lung Screening Trial (NLST) y el NEderlands Leuvens longkanker Screenings ONderzoek (NELSON) demuestran una reducción de la mortalidad que justifican la implantación del cribado en población de riesgo. Nuestro objetivo es presentar los resultados de supervivencia del programa de cribado de CP más amplio de España con tomografía computarizada de baja dosis (TCBD). Métodos: Se analizaron los datos del programa Internacional de Detección Precoz de CP (IELCAP) en Valencia, España. Este programa reclutó fumadores o exfumadores con una edad entre 40- 80 años. Se comparan los resultados con otros programas de similar tamaño. Resultados: Un total de 8.278 participantes fueron reclutados con al menos dos rondas de seguimiento, hasta noviembre de 2020 (62,8% varones), realizando una media de seis rondas de cribado por individuo. Diagnosticamos 239 tumores en 12 años de seguimiento. El adenocarcinoma fue el tumor más frecuente con un 61,3% en estadio I. Las tasas de prevalencia e incidencia fueron de 1,5% y 1,4%, respectivamente, con una tasa de detección anual de 0,17. Las tasas de supervivencia cáncer específica a cinco años fueron del 90 y del 80,1% a 10 años. La adherencia fue de 96,84%. Conclusión: La experiencia del programa más amplio de España demuestra que la supervivencia se mejora cuando se realiza en equipos multidisciplinares con experiencia en CP y es similar a programas similares. (AU)


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Programas de Rastreamento , Detecção Precoce de Câncer , Espanha , Fumantes , Ex-Fumantes
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