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The social environment can influence the functional capacity of nervous and immune systems, and consequently the state of health, especially in aged individuals. Adult female tyrosine hydroxylase haploinsufficient (TH-HZ) mice exhibit behavioral impairments, premature immunosenescence and oxidative- inflammatory stress. All these deteriorations are associated with a lower lifespan than wild type (WT) counterparts. The aim was to analyze whether the cohabitation with WT animals could revert or at least ameliorate the deterioration in the nervous and immune systems that female TH-HZ mice show at adult age. Female TH-HZ and WT mice at age of 3–4 weeks were divided into following groups: control TH-HZ (5 TH-HZ mice in the cage; TH-HZ100%), control WT (5 WT mice in the cage; WT100%), TH-HZ > 50% and WT < 50% (5 TH-HZ with 2 WT mice in each cage) as well as TH-HZ < 50% and WT > 50% (2 TH-HZ and 5 WT mice in each cage). At the age of 37–38 weeks, all mice were submitted to a battery of behavioral tests, evaluating sensorimotor abilities, exploratory capacities and anxiety-like behaviors. Subsequently, peritoneal leukocytes were extracted and several immune functions as well as oxidative and inflammatory stress parameters were analyzed. The results showed that the TH-HZ < 50% group had improved behavioral responses, especially anxiety-like behaviors, and the immunosenescence and oxidative stress of their peritoneal leukocytes were ameliorated. However, WT mice that cohabited with TH-HZ mice presented higher anxiety-like behaviors and deterioration in immune functions and in their inflammatory stress parameters. Thus, this social environment is capable of ameliorating the impairments associated with a haploinsufficiency of the th gene. [ABSTRACT FROM AUTHOR]

Cloud-to-ground lightning in a sector covering the Iberian Peninsula, the Balearic Islands and nearby seas (36-44° N, 10° W-5° E) is analysed in the period from 2003 to 2009 (7yr). Two Iberian lightning detection networks, composed of 18 sensors over Portugal and Spain, are combined for the first time in the present study. The selected characteristics are cloud-to-ground flashes (CGFs), first stroke peak current, polarity and multiplicity (number of strokes in a given flash). This study examines the temporal (on hourly, monthly and seasonal timescales) and spatial variability of CGFs. The influence of five forcing factors on lightning (elevation, lifted index, convective available potential energy and daily minimum and maximum near-surface air temperatures) over the Iberian sector is also assessed. For regional-scale assessments, six subsectors with different climatic conditions were analysed separately. Despite important regional differences, the strongest lightning activity occurs from late spring to early autumn, and mostly in the afternoon. Furthermore, CGFs are mainly located over high-elevation areas in late spring to summer, while they tend to occur over the sea in autumn. The results suggest that (1) orographically forced thunderstorms over mountainous areas, mostly from May to September, (2) tropospheric buoyancy forcing over western-central and northern regions in summer and over the Mediterranean regions in autumn, and (3) near-surface thermal contrasts from October to February largely control the location of lightning in Iberia. There is no evidence of different forcings by polarity. A clear correspondence between summertime precipitation patterns and CGFs is also found. [ABSTRACT FROM AUTHOR]

Transforming growth factor (TGF)-β and insulin display opposite effects in regulating programmed cell death during vertebrate retina development; the former induces apoptosis while the latter prevents it. In the present study we investigated coordinated actions of TGF-β and insulin in an organotypic culture system of early postnatal mouse retina. Addition of exogenous TGF-β resulted in a significant increase in cell death whereas exogenous insulin attenuated apoptosis and was capable of blocking TGF-β-induced apoptosis. This effect appeared to be modulated via insulin-induced transcriptional down-regulation of TGF-β receptor II levels. The analysis of downstream signalling molecules also revealed opposite effects of both factors; insulin provided survival signalling by increasing the level of anti-apoptotic Bcl-2 protein expression and phosphorylation and down-regulating caspase 3 activity whereas pro-apoptotic TGF-β signalling reduced Bcl-2 mRNA levels and Bcl-2 phosphorylation and induced the expression of TGF-induced immediate-early gene (TIEG), a Krüppel-like zinc-finger transcription factor, mimicking TGF-β activity. [ABSTRACT FROM AUTHOR]

Ozone is a secondary air pollutant that has received extensive attention in the literature, mainly because of the adverse effects that exposure to it can cause, particularly in vegetation during the growing season. Because meteorological conditions strongly influence the efficiency of photochemical processes leading to ozone formation and destruction, ground-level ozone air pollution is currently being considered as a regional-scale phenomenon rather than a local one. This role of O3 as a regional-scale pollutant often implies the handling of large data sets in order to obtain information about its spatial and temporal variability patterns over a given broad region. Rotated principal component analysis (RPCA) is known to be one of the most powerful mathematical tools that can be used to achieve this aim. RPCA was applied in this paper to the summer and winter hourly time series of ground-level O3, concentrations recorded during 2 consecutive years (1996–1997) at 26 urban and suburban sites in Castilla-León (Spain). This procedure permitted the identification of different subregions where O3 concentrations show different spatio-temporal variability patterns. These variability patterns are mainly associated with the interaction of regional-level meteorological and anthropogenic factors. Some differences between winter and summer patterns were also found. [ABSTRACT FROM AUTHOR]

The primary aim of the present work is to describe and analyze the temporal trends of concurrent hourly observations and its daily averaged series of the pollutants CO, NO2, NO and SO2 in the urban area of the City of Salamanca (environmental survey station SA001) for the period between 1 December 1993 and 30 November 1994. Using daily series corresponding to different meteorological variables recorded at the same site for the same period (wind direction, relative humidity, pressure, radiation, temperature and wind speed), linear regression techniques are used to study the relationships of these variables with each of the polluntants on both an individual and multivariate basis. The results obtained explain 40% of the variance of the series for NO2 and 66% in the case of SO2. Finally, in the modelling phase it was observed that the series of polluntants themselves have sufficient ’’information’’ to enable, by means of autoregressive and integrated moving average techniques (A.R.I.M.A.), the determination of future pollution. Once predicted, these were contrasted with the measured or observed values to check the goodness of the model. [ABSTRACT FROM AUTHOR]

On the basis of a qualitative index (Daily Fire Risk) for the meteorological severity, a model for predicting the daily number of forest fires over a zone is developed. DFR is obtained for each day from (e,D) values, where a is the parameter of stability in the lowest atmospheric layer (850-700 hPa) and D is the saturation deficit at lowest level (850 hPa). Both a and D are evaluated at 00.00 UTC from radwindsonde data. Four types of day may be described: I, II, III and IV-type if a classification on (e, D) values is established. Very High fireactivity is associated with type-I days; High with Type-III; Low with type IV and Very Low with type-II days. As in the case of other qualitative indices, two days which present an identical index may register a very different number of forest fires. This is due to the fact that the fire activity on a day d does not depend exclusively upon meteorological parameters of the day d. A second question to consider is related to the prediction of the daily number of fires PNF(d). In this way, an initial hypothesis may be PNF(d) = PW(d) W(d), in which PW(d) and W(d) are the Past Weather and the (present) Weather for eachday d. If several considerations such as PW(d) = PW(d-1) are introduced, a working expression for the daily number of forest fires results. The results obtained confirm the utility of the model and, consequently, it should be used to establish correct antifire management. [ABSTRACT FROM AUTHOR]