Enhancement of optical absorption in multiferroic (1-x)PZT-xPFN thin films: Experiments and first-principles analysis

Multiferroic compounds have gained research attention in the field of ferroelectric photovoltaics due to the presence of transition-metal d states from magnetic ions, which tend to reduce the bandgap value. In this work, 0.5Pb(Zr0.52Ti0.48)O3 - 0.5Pb(Fe0.5Nb0.5)O3 PZTFN0.5 thin films were synthesized using a sol-gel route to investigate the effect of iron doping on optical and multiferroic properties. For comparative analysis, the end-member compositions, Pb(Zr0.52Ti0.48)O3 (PZT) and Pb(Fe0.5Nb0.5)O3 (PFN), were also synthesized under identical conditions. Our results revealed that the presence of Fe ions, besides inducing multiferroic behavior, effectively enhances the optical absorption of the material in the visible light region. Optical transitions at 3.0 eV (2.4 eV) and 2.7 eV (2.2 eV) for the direct (indirect) bandgap were determined for PZTFN0.5 and PFN, respectively, indicating that the absorption edges of the iron-containing films result more promising than PZT (Eg 3.6eV) for photovoltaic applications. Both PZTFN0.5 and PFN thin films exhibit multiferroic behavior at room temperature, with different electric and magnetic properties. While PZTFN0.5 presents saturated hysteresis loops with remanent polarization values around 10 uC/cm2 and magnetization of 1.6 emu/cm2, PFN displays significantly larger remanence (31 emu/cm2) but poorer ferroelectric properties due to the presence of leakage. Microscopic insights into the structural and electronic properties of the PZTFN0.5 solid solution were provided from first-principles calculations

Projected increases in the annual flood pulse of the Western Amazon

The impact of a changing climate on the Amazon basin is a subject of intensive research because of its rich biodiversity and the significant role of rainforests in carbon cycling. Climate change has also a direct hydrological impact, and increasing efforts have focused on understanding the hydrological dynamics at continental and subregional scales, such as the Western Amazon. New projections from the Coupled Model Inter-comparison Project Phase 5 ensemble indicate consistent climatic warming and increasing seasonality of precipitation in the Peruvian Amazon basin. Here we use a distributed land surface model to quantify the potential impact of this change in the climate on the hydrological regime of the upper Amazon river. Using extreme value analysis, historical and future projections of the annual minimum, mean, and maximum river flows are produced for a range of return periods between 1 and 100 yr. We show that the RCP 4.5 and 8.5 scenarios of climate change project an increased severity of the wet season flood pulse (7.5% and 12% increases respectively for the 100 yr return floods). These findings agree with previously projected increases in high extremes under the Special Report on Emissions Scenarios climate projections, and are important to highlight due to the potential consequences on reproductive processes of in-stream species, swamp forest ecology, and socio-economy in the floodplain, amidst a growing literature that more strongly emphasises future droughts and their impact on the viability of the rainforest system over greater Amazonia

Historia de uso del suelo y contenido de micronutrientes en Argiudoles del centro de la provincia de Santa Fe (Argentina)

67-73The studies related to the concentration and bioavailability of soil micronutrients are very limited for the central region of Santa Fe province, reason for which the objectives of the current research were: a) to determine the decrease of the micronutrient contents in Argiudolls of Santa Fe as a consequence of soil use, and b) to correlate the micronutrient bioavailability with soil properties that were affected by the intensification of productive systems (organic matter, pH). The study was carried out in Argiudolls of Las Colonias county (Santa Fe). Composite soil samples were collected from 20 fields under pristine conditions (CP), 22 fields under milk production history (G), 24 fields under agricultural-livestock history (AG) and 20 fields under a long agricultural history (A). These samples were used to determine: pH, organic carbon (OC), boron (B), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn). The results indicate that the pH did not vary among the studied situations; the values of OC diminished 40 percent with the intensification of agriculture; the concentration of B and Zn in fields with a long agricultural history decreased 50 percent with respect to the pristine condition; the Cu concentration was not altered; Fe and Mn did not show a clear tendency to change as a function of the soil use. Zinc deficiencies could occur in some cases, therefore, its concentration should be routinely controlled, especially in intensive systems, to assure an appropriate supply of nutrients according to the crop demand

Historia de uso del suelo y contenido de micronutrientes en Argiudoles del centro de la provincia de Santa Fe (Argentina)

67-73The studies related to the concentration and bioavailability of soil micronutrients are very limited for the central region of Santa Fe province, reason for which the objectives of the current research were: a) to determine the decrease of the micronutrient contents in Argiudolls of Santa Fe as a consequence of soil use, and b) to correlate the micronutrient bioavailability with soil properties that were affected by the intensification of productive systems (organic matter, pH). The study was carried out in Argiudolls of Las Colonias county (Santa Fe). Composite soil samples were collected from 20 fields under pristine conditions (CP), 22 fields under milk production history (G), 24 fields under agricultural-livestock history (AG) and 20 fields under a long agricultural history (A). These samples were used to determine: pH, organic carbon (OC), boron (B), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn). The results indicate that the pH did not vary among the studied situations; the values of OC diminished 40 percent with the intensification of agriculture; the concentration of B and Zn in fields with a long agricultural history decreased 50 percent with respect to the pristine condition; the Cu concentration was not altered; Fe and Mn did not show a clear tendency to change as a function of the soil use. Zinc deficiencies could occur in some cases, therefore, its concentration should be routinely controlled, especially in intensive systems, to assure an appropriate supply of nutrients according to the crop demand

Invasive Haemophilus influenzae Disease in Children: National Multicentre Study 2010-2014

Introdução: Uma parceria Sociedade de Infecciologia Pediátrica / Instituto Nacional de Saúde Dr. Ricardo Jorge propôs-se avaliar a epidemiologia, fatores de risco, clínica, serotipos e suscetibilidade aos antibióticos da doença invasiva a Haemphilus influenzae nas crianças, em Portugal. Métodos: Estudo prospetivo descritivo multicêntrico, entre 1 de janeiro de 2010 e 30 de junho de 2014 (54 meses). Cada estirpe foi enviada ao Instituto Nacional de Saúde Dr. Ricardo Jorge acompanhada de inquérito clínico. Foi pesquisada produção de β-lactamase, resistência antibiótica, cápsula e serotipo. Resultados: Foram analisadas 38 estirpes (18 hospitais) isoladas em hemocultura (34), liquor (três) e líquido articular (uma). A incidência global foi 0,45/100000. Identificaram-se 25 (65,7%) Haemophilus influenzae não-capsulados, nove (23,7%) serotipo b (seis falências vacinais), duas (5,3%) serotipo a e duas (5,3%) serotipo f. As idades variaram entre 1 mês e 15 anos (lactentes 44,7%; 5 anos ou mais 26,3%); 23,7% tinham patologia prévia. As apresentações clínicas foram pneumonia (13), meningite (cinco), bacteriemia (cinco), infeção respiratória alta (quatro), bronquiolite (três) sépsis sem foco (três), artrite (duas), celulite periorbitária (uma), celulite (uma), epiglotite (uma). A meningite foi manifestação de 33,3% das infeções por serotipo b e de 4% das devidas a Haemophilus influenzae não-capsulados (p < 0,05). As infeções respiratórias altas bacteriémicas predominaram acima dos 5 anos (30% vs 3,6%; p < 0,05). Registaram-se sequelas neurológicas num caso (2,6%) e um óbito (2,6%). Verificou-se produção de β-lactamase em 7,9% e resistência à cefuroxima em 18,4%. Sem resistências a amoxicilina / clavulanato, cefotaxima, rifampicina. Discussão: A doença invasiva por Haemophilus influenzae atingiu diferentes grupos etários, predominando nos lactentes. As estirpes mais prevalentes foram de Haemophilus influenzae não-capsulados, causando maioritariamente bacteriemia e manifestações respiratórias. O serotipo b manteve-se em circulação sendo responsável por dois casos / ano

A critical assessment of the JULES land surface model hydrology for humid tropical environments

Global land surface models (LSMs) such as the Joint UK Land Environment Simulator (JULES) are originally developed to provide surface boundary conditions for climate models. They are increasingly used for hydrological simulation, for instance to simulate the impacts of land use changes and other perturbations on the water cycle. This study investigates how well such models represent the major hydrological fluxes at the relevant spatial and temporal scales-an important question for reliable model applications in poorly understood, data-scarce environments. The JULES-LSM is implemented in a 360 000 km2 humid tropical mountain basin of the Peruvian Andes-Amazon at 12-km grid resolution, forced with daily satellite and climate reanalysis data. The simulations are evaluated using conventional discharge-based evaluation methods, and by further comparing the magnitude and internal variability of the basin surface fluxes such as evapotranspiration, throughfall, and surface and subsurface runoff of the model with those observed in similar environments elsewhere. We find reasonably positive model efficiencies and high correlations between the simulated and observed streamflows, but high root-mean-square errors affecting the performance in smaller, upper sub-basins. We attribute this to errors in the water balance and JULES-LSM's inability to model baseflow. We also found a tendency to under-represent the high evapotranspiration rates of the region. We conclude that strategies to improve the representation of tropical systems to be (1) addressing errors in the forcing and (2) incorporating local wetland and regional floodplain in the subsurface representation

A combined view on precipitation and temperature climatology and trends in the southern Andes of Peru

In the southern Peruvian Andes, communities are highly dependent on climatic conditions due to the mainly rain-fed agriculture and the importance of glaciers and snow melt as a freshwater resource. Longer-term trends and year-to-year variability of precipitation or temperature severely affect living conditions. This study evaluates seasonal precipitation and temperature climatologies and trends in the period 1965/66–2017/18 for the southern Peruvian Andes using quality-controlled and homogenized station data and new observational gridded data. In this region, precipitation exhibits a strong annual cycle with very dry winter months and most of the precipitation falling from spring to autumn. Spatially, a northeast–southwest gradient in austral spring is observed, related to an earlier start of the rainy season in the northeastern partof the study area. Seasonal variations of maximum temperature are weak withan annual maximum in austral spring, which is related to reduced cloud coverin austral spring compared to summer. On the contrary, minimum tempera-tures show larger seasonal variations, possibly enhanced through changes inlongwave incoming radiation following the precipitation cycle. Precipitationtrends since 1965 exhibit low spatial consistency except for austral summer,when in most of the study area increasing precipitation is observed, and in aus-tral spring, when stations in the central-western region of the study area regis-ter decreasing precipitation. All seasonal and annual trends in maximum temperature are larger than trends in minimum temperature. Maximum temperature exhibits strong trends in austral winter and spring, whereas minimum temperature trends are strongest in austral winter. We hypothesize, that these trends are related to precipitation changes, as decreasing (increasing) precipita-tion in spring (summer) may enhance maximum (minimum) temperature trends through changes in cloud cover. El Niño Southern Oscillation (ENSO), however, has modifying effects onto precipitation and temperature, and thereby leads to larger trends in maximum temperatures

A Osteomielite Crónica pode ser o Precedente de uma Infeção por Corynebacterium Diphtheriae

INTRODUÇÃO E OBJETIVOS: A infeção por Corynebacterium diphtheriae não toxinogénica tem sido cada vez mais descrita e associada a doença grave e disseminada, como endocardite, artrite séptica e osteomielite1, podendo estar associada a doentes com infeções ósseas ou ar6culares, entre outras. 2 A vacinação não é protetora para C. diphtheriae não toxinogénica. 3 Apresentamos o caso clínico de uma doente com fractura exposta do úmero com 1 ano de evolução com sinais de osteomielite crónica e isolamento de C. diphtheriae, S. aureus e S. pyogenes. CASO CLÍNICO: Rapariga de 11 anos Natural e residente na Guiné Desconhece-se estado vacinal. Desconhece-se contexto epidemiológico. Foi fieto: DESBRIDAMENTO e fistulectomia FLUCLOXACILINA e RIFAMPICINA 12semanas + PENICILINA 3 semanas; boa evolução aos 3 meses. CONCLUSÃO: A difteria cutânea é causada por estirpes de Corynebacterium diphteriae, produtoras ou não de toxina. Caracterizam-se por úlceras cutâneas crónicas, que servem como reservatório. A probabilidade de envolvimento faríngeo é rara. É possível, que possa ter algum papel como agente patogénico na osteomielite crónica, em co-infeção com S. aureus2, tal como no caso apresentado.info:eu-repo/semantics/publishedVersio

Trehalose-based siamese twin amphiphiles with tunable self-assembling, DNA nanocomplexing and gene delivery properties

An original family of multivalent vectors encompassing gemini and facial amphiphilicity, namely cationic Siamese twin surfactants, has been prepared fromthe disaccharide trehalose; molecular engineering lets us modulate the self-assembling properties and the topology of the nanocomplexes with plasmid DNA for efficient gene delivery in vitro and in vivo

Prox1 Is Required for Granule Cell Maturation and Intermediate Progenitor Maintenance During Brain Neurogenesis

The transcription factor Prox1 plays a crucial role in intermediate progenitor maintenance and hippocampal neuron differentiation during adult neurogenesis in the dentate gyrus region of the hippocampus