1,272 research outputs found
The infuence of land use on water quality and macroinvertebrate biotic indices in rivers within Castilla-La Mancha(Spain)
Con el objetivo de determinar la influencia de los usos del suelo en la calidad de los ecosistemas fluviales de Castilla-La Mancha, se han analizado variables fÃsico-quÃmicas (conductividad eléctrica, nitrato, nitrito, amonio, fosfato) y varios Ãndices de invertebrados bentónicos (IBMWP, BMWQ y MCLM). En total, se muestrearon 82 tramos fluviales pertenecientes a las cuencas del Tajo, Guadiana, Júcar, y Segura, durante el verano de 2001. Se calculó el porcentaje de cada uso del suelo a escala regional (área de drenaje), obtenidos a partir del CORINE Land Cover y herramientas del software ArcGIS 9.0. Los resultados del análisis de correlación mostraron relaciones altamente significativas entre los nutrientes e Ãndices bióticos y los usos urbano, forestal y agrÃcola de secano. En el caso del uso agrÃcola de regadÃo se detectaron correlaciones más débiles con nutrientes (nitrato y fosfato) y los Ãndices bióticos. Dada la importancia de la agricultura en la región de Castilla-La Mancha (53% de ocupación del suelo) y los efectos en el ecosistema fluvial se apunta la necesidad de mejorar el tratamiento de residuos urbanos, asà como unas buenas prácticas aplicadas en la agricultura y mantenimiento del bosque de riberaWith the objective to determine the influence of land use on the quality of the fluvial ecosistms within Castilla-La Mancha, Spain, physicochemical variables (conductivity, concentrations of ammonium, nitrite, nitrate, phosphate) and various benthic invertebrates indices (IBMWP, BMWQ and MCLM) were measured. In total, 82 stretches of rivers belonging to the Tajo, Guadiana, Jucar and Segura watersheds were sampled during the summer of 2001. The percentage of every land use type on a regional scale (drainage area) was calculated, obtained from the CORINE Land Cover and tools from ArcGIS 9.0 software. The correlation analysis results showed a significantly strong relationship between nutrients and biotic indices and the urban, forested and dry agriculture uses. For irrigated agriculture, low correlations were found for nutrients (nitrate and phosphate) and biotic indices. Given the importance of agriculture in the Castilla-La Mancha Region (53% of the area) and the effects on the fluvial ecosystems, this study highlights the need for, improved wastewater treatment, as well as good agricultural management practices and the maintenance of the riparian corrido
EP-1245: Gated Rapidarc using KV intrafraction verification for liver stereotactic treatment
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Large-Mass Ultra-Low Noise Germanium Detectors: Performance and Applications in Neutrino and Astroparticle Physics
A new type of radiation detector, a p-type modified electrode germanium
diode, is presented. The prototype displays, for the first time, a combination
of features (mass, energy threshold and background expectation) required for a
measurement of coherent neutrino-nucleus scattering in a nuclear reactor
experiment. The device hybridizes the mass and energy resolution of a
conventional HPGe coaxial gamma spectrometer with the low electronic noise and
threshold of a small x-ray semiconductor detector, also displaying an intrinsic
ability to distinguish multiple from single-site particle interactions. The
present performance of the prototype and possible further improvements are
discussed, as well as other applications for this new type of device in
neutrino and astroparticle physics (double-beta decay, neutrino magnetic moment
and WIMP searches).Comment: submitted to Phys. Rev.
Algorithm and performance of a clinical IMRT beam-angle optimization system
This paper describes the algorithm and examines the performance of an IMRT
beam-angle optimization (BAO) system. In this algorithm successive sets of beam
angles are selected from a set of predefined directions using a fast simulated
annealing (FSA) algorithm. An IMRT beam-profile optimization is performed on
each generated set of beams. The IMRT optimization is accelerated by using a
fast dose calculation method that utilizes a precomputed dose kernel. A compact
kernel is constructed for each of the predefined beams prior to starting the
FSA algorithm. The IMRT optimizations during the BAO are then performed using
these kernels in a fast dose calculation engine. This technique allows the IMRT
optimization to be performed more than two orders of magnitude faster than a
similar optimization that uses a convolution dose calculation engine.Comment: Final version that appeared in Phys. Med. Biol. 48 (2003) 3191-3212.
Original EPS figures have been converted to PNG files due to size limi
Prevalence and Prognostic Influence of Peripheral Arterial Disease in Patients ≥40 Years Old Admitted into Hospital Following an Acute Coronary Event
AbstractObjectiveA significant proportion of patients with ischemic heart disease have associated peripheral arterial disease (PAD), but many are asymptomatic and this condition remains underdiagnosed. We aimed to study the prevalence of PAD in patients with an acute coronary syndrome (ACS) and to evaluate its influence in hospital clinical outcomes.MethodsThe PAMISCA register is a prospective, multicenter study involving patients ≥40 years old with ACS admitted to selected Spanish hospitals. All patients had their ankle-brachial index (ABI) measured between days 3 and 7 after the ischemic event.Results1410 ACS patients (71.4% male) were included. PAD determined by ABI was documented in 561 patients (39.8%). Factors independently related to PAD were age (OR: 1.04; 95% CI: 1.03–1.06; p<0.001), smoking (OR: 1.88; 95% CI: 1.41–2.49; p<0.0001), diabetes (OR: 1.30; 95% CI: 1.02–1.65; p<0.05), previous cardiac disease (OR: 1.54; 95% CI: 1.22–1.95; p<0.001) and previous cerebrovascular disease (OR: 1.90; 95% CI: 1.28–2.80; p<0.001). Following the ACS, an ABI≤0.90 was associated with increased cardiovascular mortality (OR: 5.45; 95% CI: 1.16–25.59; p<0.05) and a higher risk of cardiovascular complications.ConclusionThe prevalence of PAD in patients ≥40 years presenting with ACS is high and it is associated with increased cardiovascular risk
Effet de deux agents de blanchiment sur la surface de l’émail. Etude in vitro
We present a study «in vitro» of the effect of bleaching agents on dental surfaces using the «Walking bleaching technique». We found that hydrogen peroxide bleached more quickly than carbamide although, after a period of six weeks, the results were the same as far as wheitening was concerned. In the scanning electron microscope we observed significantly different changes in each case. Carbamide caused a regular and uniform opening of the enamel prisms of the surface while hydrogen peroxide produced more severe superficial destructuration with the appearance of patterning similar to the acid etching, and the presence of some crystalline areas emerging from the body of the prisms.Nous présentons une étude in vitro de l’effet sur la surface dentaire de deux agents de blanchiment utilisés par la technique «Walking bleaching». Nous observons que le peroxyde d’hydrogène blanchit plus vite que le peroxyde de carbamide même si dans un délai de 6 semaines les résultats sont les mêmes en ce qui concerne le blanchiment. Au MEB, nous observons des changements significativement différents dans l’un et l’autre cas. Le peroxyde de carbamide provoque une ouverture des prismes sur la surface de l’émail de manière régulière et uniforme, alors que le peroxyde d’hydrogène produit des destructurations superficielles plus importantes avec l’apparition d’un maître-modèle comme celui de mordançage acide avec la présence sur certaines zones de cristaux qui émergent du corps des prismes
The MADS-Box Factor CeMEF2 Is Not Essential for Caenorhabditis elegans Myogenesis and Development
AbstractMEF2 is an evolutionarily conserved MADS (MCM1, Agamous, Deficiens, and serum response factor) box-type transcription factor that plays a critical role in vertebrate and Drosophila melanogaster myogenesis. We have addressed the developmental role of the single MEF2-like factor, CeMEF2, in Caenorhabditis elegans. Using expression assays and two mef-2 deletion alleles, we show that CeMEF2 is not required for proper myogenesis or development. Moreover, a putative null mef-2 allele fails to enhance or suppress the phenotypes of mutants in CeMyoD or CeTwist. Our results suggest that despite its evolutionary conservation of sequence and DNA binding properties, CeMEF2 has adopted a divergent role in development in the nematode compared with Drosophila and vertebrates
Studies on the coastal ecology and management of the Nabq Protected Area, South Sinai, Egypt.
The dopaminergic system provides the basis for the interaction between motivation and cognition. It is triggered by the possibility of obtaining rewards to initiate the neurobehavioral adaptations necessary to achieve them by directing the information from motivational circuits to cognitive and action circuits. In drug addiction, the altered dopamine (DA) modulation of the meso-cortico-limbic reward circuitry, such as the prefrontal cortex (PFC), underlies the disproportionate motivational value of drug use at the expense of other nondrug reinforcers and the user''s loss of control over his/her drug intake. We examine how the magnitude of the reward affects goal-directed processes in healthy control (HC) subjects and abstinent cocaine dependent (ACD) patients by using functional magnetic resonance imaging (fMRI) during a counting Stroop task with blocked levels of monetary incentives of different magnitudes (€0, €0.01, €0.5, €1 or €1.5). Our results showed that increasing reward magnitude enhances (1) performance facilitation in both groups; (2) left dorsolateral prefrontal cortex (DLPFC) activity in HC and left superior occipital cortex activity in ACD; and (3) left DLPFC and left putamen connectivity in ACD compared to HC. Moreover, we observed that (4) dorsal striatal and pallidum activity was associated with craving and addiction severity during the parametric increases in the monetary reward. In conclusion, the brain response to gradients in monetary value was different in HC and ACD, but both groups showed improved task performance due to the possibility of obtaining greater monetary rewards
Long-term benefits and risks of frontline nilotinib vs imatinib for chronic myeloid leukemia in chronic phase: 5-year update of the randomized ENESTnd trial
Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector
A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV
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