505 research outputs found
Neuro-hormonal effects of physical activity in the elderly.
Thanks to diagnostic and therapeutic advances, the elderly population is continuously increasing in the western countries. Accordingly, the prevalence of most chronic age-related diseases will increase considerably in the next decades, thus it will be necessary to implement effective preventive measures to face this epidemiological challenge. Among those, physical activity exerts a crucial role, since it has been proven to reduce the risk of cardiovascular diseases, diabetes, obesity, cognitive impairment and cancer. The favorable effects of exercise on cardiovascular homeostasis can be at least in part ascribed to the modulation of the neuro-hormonal systems implicated in cardiovascular pathophysiology. In the elderly, exercise has been shown to affect catecholamine secretion and biosynthesis, to positively modulate the renin-angiotensin-aldosterone system and to reduce the levels of plasma brain natriuretic peptides. Moreover, drugs modulating the neuro-hormonal systems may favorably affect physical capacity in the elderly. Thus, efforts should be made to actually make physical activity become part of the therapeutic tools in the elderly. © 2013 Femminella, de Lucia, Iacotucci, Formisano, Petraglia, Allocca, Ratto, DAmico, Rengo, Pagano, Bonaduce, Rengo and Ferrara
Acute stress impairs sensorimotor gating via the neurosteroid allopregnanolone in the prefrontal cortex
Ample evidence indicates that environmental stress impairs information processing, yet the underlying mechanisms remain partially elusive. We showed that, in several rodent models of psychopathology, the neurosteroid allopregnanolone (AP) reduces the prepulse inhibition (PPI) of the startle, a well-validated index of sensorimotor gating. Since this GABAA receptor activator is synthesized in response to acute stress, we hypothesized its participation in stress-induced PPI deficits. Systemic AP administration reduced PPI in C57BL/6J mice and Long-Evans, but not Sprague-Dawley rats. These effects were reversed by isoallopregnanolone (isoAP), an endogenous AP antagonist, and the GABAA receptor antagonist bicuculline and mimicked by AP infusions in the medial prefrontal cortex (mPFC). Building on these findings, we tested AP's implication in the PPI deficits produced by several complementary regimens of acute and short-term stress (footshock, restraint, predator exposure, and sleep deprivation). PPI was reduced by acute footshock, sleep deprivation as well as the combination of restraint and predator exposure in a time- and intensity-dependent fashion. Acute stress increased AP concentrations in the mPFC, and its detrimental effects on PPI were countered by systemic and intra-mPFC administration of isoAP. These results collectively indicate that acute stress impairs PPI by increasing AP content in the mPFC. The confirmation of these mechanisms across distinct animal models and several acute stressors strongly supports the translational value of these findings and warrants future research on the role of AP in information processing
High temperature stability of Terphenyl based thermal oils
Thermal oils are nowadays widely used as heat transfer fluids or cooling media in industrial and energy production plants. Currently, very few data are available about their thermal stability in function of the operating temperatures, which is a crucial parameter to estimate oil structural changes and their possible effects the maximum fluids lifetime.
The present work is concerned with ageing tests on a commercially used thermal oil at temperatures higher than the nominal working ones, including a full post-test characterization.
At this aim, a dedicated experimental set-up was designed and constructed to study the degradation kinetics, and to qualitatively and quantitatively analyze the released gases. As a result, the kinetic parameters were estimated, along with the related changes in the oil thermos-physical properties
S011-05 OA. HLA-A*7401 is associated with protection from HIV-1 acquisition and disease progression in Mbeya, Tanzania
Application of a physically based model to forecast shallow landslides at a regional scale
<p>In this work, we apply a physically based model, namely the
HIRESSS (HIgh REsolution Slope Stability Simulator) model, to forecast the
occurrence of shallow landslides at the regional scale. HIRESSS is a physically
based distributed slope stability simulator for analyzing shallow landslide
triggering conditions during a rainfall event. The modeling software is made up of two
parts: hydrological and geotechnical. The hydrological model is based on an
analytical solution from an approximated form of the Richards equation, while
the geotechnical stability model is based on an infinite slope model that
takes the unsaturated soil condition into account. The test area is a portion
of the Aosta Valley region, located in the northwest of the Alpine mountain chain. The
geomorphology of the region is characterized by steep slopes with elevations
ranging from 400 m a.s.l. on the Dora Baltea River's floodplain to
4810 m a.s.l. at Mont Blanc. In the study area, the mean annual
precipitation is about 800–900 mm. These features make the territory
very prone to landslides, mainly shallow rapid landslides and rockfalls.
In order to apply the model and to increase its reliability, an in-depth
study of the geotechnical and hydrological properties of hillslopes
controlling shallow landslide formation was conducted. In particular, two
campaigns of on site measurements and laboratory experiments were performed
using 12 survey points. The data collected contributed to the generation of an input map
of parameters for the HIRESSS model. In order to consider the effect of
vegetation on slope stability, the soil reinforcement due to the presence of
roots was also taken into account; this was done based on vegetation maps and
literature values of root cohesion. The model was applied using back analysis
for two past events that affected the Aosta Valley region between 2008 and
2009, triggering several fast shallow landslides. The validation of the
results, carried out using a database of past landslides, provided good
results and a good prediction accuracy for the HIRESSS model from both a
temporal and spatial point of view.</p
OA04-03. Characterization of cell-mediated immune responses generated by recombinant modified vaccinia Ankara (rMVA)-HIV-1 in a phase I vaccine trial
La gran erupción de hace 4.2 ka cal en Cerro Blanco, Zona Volcánica Central, Andes: nuevos datos sobre los depósitos eruptivos holocenos en la Puna sur y regiones adyacentes
The eruption of the Cerro Blanco Volcanic Complex, in the southern Puna, NW Argentina dated at 4410–4150 a cal BP, was investigated to produce new information on stratigraphy, geomorphology, physical volcanology, radiocarbon dating, petrography, and geochemistry. Identification of pre–, syn–, and post–caldera products allowed us to estimate the distribution of the Plinian fallout during the paroxysmal syn–caldera phase of the eruption. The new results provide evidence for a major rhyolitic explosive eruption that spread volcanic deposits over an area of ~500,000 km2, accumulating > 100 km3 of tephra (bulk volume). This last value exceeds the lower threshold of Volcanic Explosive Index (VEI) of 7. Ash-fall deposits mantled the region at distances > 400 km from source and thick pyroclastic-flow deposits filled neighbouring valleys up to 35 km away. This eruption is the largest documented during the past five millennia in the Central Volcanic Zone of the Andes, and is probably one of the largest Holocene explosive eruptions in the world. We have also identified two additional rhyolitic eruptions in the region from two other eruptive sources: one during the Early–Holocene and another in the Late–Holocene. The identification and characterisation of these significant volcanic events provide new constraints into regional Holocene geological and archaeological records, and offer extensive regional chronostratigraphic markers over a wide geographical area of South America.La erupción del Complejo Volcánico Cerro Blanco en el sur de la Puna, noroeste de Argentina (4410–4150 a BP) se investigó para obtener nueva información sobre estratigrafía, geomorfología, volcanología física, dataciones por radiocarbono, petrografía y geoquímica. La caracterización de los productos en relación a la evolución de la caldera de Cerro Blanco permitió estimar la distribución de los depósitos de ceniza de la fase paroxísmica Plineana de la erupción. Estos novedosos resultados evidencian una gran erupción explosiva riolítica que generó depósitos cineríticos en un área de aproximadamente 500.000 km2, acumulando > 100 km3 de tefra (volumen total). Este último valor supera el umbral inferior del Índice de Explosividad Volcánica (IEV) de 7. Los depósitos de caída de ceniza cubrieron la región, llegando a más de 400 km desde el Complejo Volcánico de Cerro Blanco, y los potentes depósitos de flujos piroclásticos rellenaron los valles vecinos alcanzando una distancia de 35 km. Esta erupción es la más grande documentada durante los últimos cinco milenios en la Zona Volcánica Central de los Andes y es probablemente una de las mayores erupciones explosivas holocenas del mundo. Además, se han identificado otras dos erupciones riolíticas en la región procedentes de otros dos centros eruptivos: una durante el Holoceno temprano y otra en el Holoceno tardío. La identificación y caracterización de estos grandes eventos volcánicos proporcionan nuevas guías para los registros geológicos y arqueológicos regionales del Holoceno, siendo marcadores cronostratigráficos de aplicación a una extensa área geográfica de América del Sur
Generaci?n de valor a trav?s de la transformaci?n de residuos de cart?n en mobiliario en el marco de la Responsabilidad Social Empresarial de Sociedad Minera Cerro Verde S.A.A.
El presente trabajo de investigaci?n eval?a la generaci?n de valor de un proyecto de responsabilidad social impulsado por una de las empresas mineras m?s importantes del Per?, Sociedad Minera Cerro Verde (SMCV). El proyecto consiste espec?ficamente en la producci?n de escritorios de diferentes tama?os, elaborados a partir de cart?n proveniente de desechos libres de contaminantes, y la distribuci?n a los colegios estatales de Arequipa que es una de las regiones con mayor porcentaje de centros educativos con capacidad instalada inadecuada. Para realizar la valorizaci?n se proyect? el ahorro en compra de escritorios por parte de las autoridades que podr?a destinarse a otras actividades, el ahorro por emisiones de CO2, un peque?o aporte en la reputaci?n de SMCV, la p?rdida de las ventas del cart?n por parte de la empresa y la mejora en el diferencial de los ingresos futuros de los beneficiarios
The risk stratification of adverse neonatal outcomes in women with gestational diabetes (STRONG) study
Aims: To assess the risk of adverse neonatal outcomes in women with gestational diabetes (GDM) by identifying subgroups of women at higher risk to recognize the characteristics most associated with an excess of risk. Methods: Observational, retrospective, multicenter study involving consecutive women with GDM. To identify distinct and homogeneous subgroups of women at a higher risk, the RECursive Partitioning and AMalgamation (RECPAM) method was used. Overall, 2736 pregnancies complicated by GDM were analyzed. The main outcome measure was the occurrence of adverse neonatal outcomes in pregnancies complicated by GDM. Results: Among study participants (median age 36.8 years, pre-gestational BMI 24.8 kg/m2), six miscarriages, one neonatal death, but no maternal death was recorded. The occurrence of the cumulative adverse outcome (OR 2.48, 95% CI 1.59–3.87), large for gestational age (OR 3.99, 95% CI 2.40–6.63), fetal malformation (OR 2.66, 95% CI 1.00–7.18), and respiratory distress (OR 4.33, 95% CI 1.33–14.12) was associated with previous macrosomia. Large for gestational age was also associated with obesity (OR 1.46, 95% CI 1.00–2.15). Small for gestational age was associated with first trimester glucose levels (OR 1.96, 95% CI 1.04–3.69). Neonatal hypoglycemia was associated with overweight (OR 1.52, 95% CI 1.02–2.27) and obesity (OR 1.62, 95% CI 1.04–2.51). The RECPAM analysis identified high-risk subgroups mainly characterized by high pre-pregnancy BMI (OR 1.68, 95% CI 1.21–2.33 for obese; OR 1.38 95% CI 1.03–1.87 for overweight). Conclusions: A deep investigation on the factors associated with adverse neonatal outcomes requires a risk stratification. In particular, great attention must be paid to the prevention and treatment of obesity
Culture, technology and local networks: towards a sociology of ‘making’ in education
This article is about ‘making’ in education. Often associated with software programming (as in ‘digital making’), making can also involve creating or modifying physical technological artefacts. In this paper, making is examined as a phenomenon that occurs at the intersection of culture, the economy, technology and education. The focus is not on the effects on cognitive gains or motivations, but on locating making in a social, historical and economic context. Making is also described as a form of ‘material connotation’, where connotation refers to the process through which the technical structure of artefacts is altered by culture and society. In the second part of the paper, the theoretical discussion is complemented by a case study in which making is described as a networked phenomenon where technology companies, consultants, volunteers, schools, and students were all implicated in turning a nebulous set of practices and discourses into an educational reality
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