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The ALANIS-Aerosols project is a feasibility study on the use of existing satellite data for discriminating between natural aerosols emitted by boreal Eurasian forests and long-range transported anthropogenic aerosols. In this paper an overview is provided of different satellite products which are potentially useful to obtain this kind of information. Approaches that have been followed in the past are briefly summarized. Secondary production of aerosols from their precursor gases, in particular biogenic volatile organic compounds which play an important role in the formation of new particles through nucleation, is briefly discussed. These newly formed particles are initially too small to observe directly with optical instruments used for earth observation (EO) but through the use of proxies information can be obtained on global nucleation mode aerosol concentrations. Next we focus on aerosols with particle sizes in the optically active size range, roughly particles with a diameter larger than 50-100 nm, depending on wavelength. These particles can be observed with EO instruments as well as using several different types of in situ observations. The satellite data used are aerosol properties retrieved from the Advanced Along Track Scanning Radiometer (AATSR, flying on ENVISAT since 2002) using both the forward and nadir view with the AATSR dual view algorithm (ADV). Ground-based in situ data used here are aerosol properties measured in Hyytiälä, Finland. These observations are complemented with model calculations using the global atmospheric aerosol and chemistry model GLOMAP. Examples show the complementarity of different data sources to obtain information on the temporal and spatial information on the nature of aerosols over the Boreal forest. [ABSTRACT FROM AUTHOR]

Global active fire maps have been produced over a 21-month period from April 1992 to December 1993. A contextual active fire detection algorithm has been applied to the NOAA AVHRR (National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer) 1.1 km images provided by the IGBP-DIS (International Geosphere-Biosphere Programme Data and Information System) 1 km AVHRR Global Land Project data set. The Global Fire Product (GFP) is composed of daily fire position tables, 10-day synthesis raster format maps containing fire density and cloud/no-data information; it is now available as the first global scale description of the spatial and temporal distribution of active vegetation fire. In answer to science community requirements the GFP supplies information which can be used to estimate fire impacts on atmospheric chemistry, climate, land use and land cover changes. [ABSTRACT FROM AUTHOR]

Vegetation fires occur worldwide, all year round and inject enormous amounts of trace gases and particles into the atmosphere. Nonetheless, there is still great uncertainty as to the global spatial and temporal distribution of vegetation fires. Twenty one months of global, daily, daytime satellite data at 1 km resolution, from April 1992 to December 1993, were processed in order to determine the positions of active vegetation fires. Results from the first twelve months of the study period are presented here. This is the first time that such a global study has been carried out using a long time series data set and a single processing technique. The data set and results discussed provide much improved information on the spatial variability and the seasonality of vegetation fires. They will be of use in the global mapping and modelling of emissions due to biomass burning as well as in the study of the role of fire in land cover maintenance and change. We show that half of the fires detected were on the African continent and over 70% within the tropical belt. Fires were detected in more than 6% of 1 km[sup 2] pixels, over land, during the 12-month period and savanna grasslands accounted for over one third of this area. [ABSTRACT FROM AUTHOR]

Presents a study on paternally expressed gene Peg3. Relationship between body weight and total fat in wild-type and mutant animals; Composition of adult wild-type and Peg3+/- serum; Role of Peg3 in energy regulation.

Background: Papaya, a nutritious tropical fruit, is consumed both in its fresh form and as a processed product worldwide. Major quality indices which include firmness, acidity, pH, colour and size, are cultivar dependent. Transgenic papayas engineered for resistance to Papaya ringspot virus were evaluated over the ripening period to address physicochemical quality attributes and food safety concerns., Results: With the exception of one transgenic line, no significant differences (P > 0.05) were observed in firmness, acidity and pH. Lightness (L*) and redness (a*) of the pulps of non-transgenic and transgenic papaya were similar but varied over the ripening period (P < 0.05). Fruit mass, though non-uniform (P < 0.05) for some lines, was within the range reported for similar papaya cultivars, as were shape indices of female fruits. Transgene proteins, CP and NPTII, were not detected in fruit pulp at the table-ready stage., Conclusion: The findings suggest that transformation did not produce any major unintended alterations in the physicochemical attributes of the transgenic papayas. Transgene proteins in the edible fruit pulp were low or undetectable., (© 2013 Society of Chemical Industry.)

The stimulating action of anti-depressant drugs on the number of mitotic cells on the dentate gyrus on the adult rat depends on an intact diurnal rhythm of corticosterone. This suggests that there may be a clock mechanism in the dentate gyrus which is sensitive to corticoids. This paper reports the diurnal expression the 'clock' gene per1 in the dentate gyrus, and how it is altered by clamping the diurnal rhythm in corticosterone. We show that there is a diurnal rhythm in the number of mitotic progenitor cells in the dentate gyrus of the hippocampus in adult male per1-luciferase rats, approximately 6 h out of phase with the plasma corticosterone rhythm. This is suppressed by clamping the daily corticosterone levels by a subcutaneous implant of corticosterone (100 mg). There was also a daily rhythm of per1 expression in both suprachiasmatic nucleus (SCN) and the dentate gyrus, which were in phase with one another. The per1 rhythm in the dentate gyrus, but not the SCN, was suppressed by clamping the plasma corticosterone rhythm. These results are related to the previous finding that clamping the corticosterone rhythm also prevents the stimulating action of fluoxetine and other controlling agents on the mitotic activity of the progenitor cells., (© 2010 Elsevier Ireland Ltd. All rights reserved.)

The 5-HT re-uptake inhibitor (SSRI) fluoxetine and the adrenal hormone dehydroepiandrosterone (DHEA) both increase the proliferation of progenitor cells in the adult hippocampus and also have antidepressant activity. This paper explores the combined ability of fluoxetine and DHEA to affect this process in the dentate gyrus of adult rats. We show that DHEA can render an otherwise ineffective dose of fluoxetine (2.5 mg/kg) able to increase progenitor cell proliferation to the same extent as doses four times higher (10 mg/kg). This synergistic action does not appear to be mediated by alterations in brain-derived neurotrophic factor (BDNF) gene expression; or by TrkB, mineralocorticoid, glucocorticoid, or 5-HT (5HT1A) receptor expression in the dentate gyrus; or by altered levels of plasma corticosterone. In a second experiment, the synergism between DHEA and fluoxetine was replicated. Furthermore, flattening the diurnal rhythm of plasma corticosterone by implanting additional corticosterone pellets s.c. prevented the effect of fluoxetine on progenitor cell division. This was not overcome by simultaneous treatment with DHEA, despite the latter's reported anti-glucocorticoid actions. The cellular mechanism for the potentiating action of DHEA on the pro- proliferative effects of fluoxetine in the adult hippocampus remains to be revealed. Since altered neurogenesis has been linked to the onset or recovery from depression, one consequence of these results is to suggest DHEA as a useful adjunct therapy for depression.

Exposure of the rat to restraint results in activation of the hypothalamic-pituitary-adrenal (HPA) axis, a characteristic pattern of c-fos expression in the brain and increased cardiovascular function. These responses adapt with repeated exposure of an individual to the same stress. Corticosterone secretion habituates, and c-fos mRNA expression in the paraventricular nucleus of the hypothalamus (PVN) decreases. The increased expression of corticotropin releasing hormone mRNA in the PVN also becomes less prominent, whereas vasopressin mRNA progressively increases. The neural mechanisms responsible for this adaptation remain obscure. Because of its role in conditioned learning, we have hypothesised that the amygdala might be involved in this adaptive process. Here we show that large neurotoxic lesions of the amygdala in male rats do not prevent acute stress activation of the HPA axis following 30 min restraint, whilst more discrete lesions of the central nucleus actually exacerbate the acute response. Rats with large amygdala lesions demonstrate delayed habituation of corticosterone and c-fos to repeated restraint, an affect not apparent with central nucleus lesions. Furthermore we show that neither type of lesion significantly reduced tachycardiac responses to single or repeated restraint as measured by telemetry. We conclude that the amygdala and the central nucleus are not necessary for HPA and cardiovascular activation in response to stress (though the central nucleus may modulate it), and that adaptation to repeated stress is only modestly dependent upon the amygdala.

It has recently been suggested that gut-derived PYY(3-36) may be involved in the central mediation of post-prandial satiety signals. We have examined the acute effects of peripherally administered PYY(3-36) on food intake and hypothalamic gene expression of neuropeptides in mice. A single intraperitoneal injection of PYY(3-36) to mice that had been fasted for 24h resulted in a highly significant reduction in food intake at 6 and 24h post-injection but not at 48h. However, in freely fed mice, food intake was unaltered by PYY(3-36) administration. In the arcuate nucleus POMC mRNA expression was significantly elevated at 6h and remained elevated at 24h following PYY(3-36) injection. By contrast NPY mRNA expression in the arcuate nucleus was suppressed at 6h but not at 24h post-injection. In the lateral hypothalamus there were no differences in MCH mRNA expression at either time point. In conclusion, peripherally administered PYY(3-36) has a suppressive effect on food intake that is more prominent in recently fasted mice and lasts up to 24 h. This is associated with a short-lived suppression of NPY mRNA, a longer lasting increase in POMC mRNA but no change in MCH mRNA expression.

Interactions between serotonin and corticotropin-releasing factor (CRF) have been demonstrated by various studies in different parts of the brain. Both are activated by stressful stimuli. Additionally, serotoninergic fibres directly synapse with the parvocellular division of the paraventricular nucleus (PVN) that mainly synthesize CRF. The functional impact of this serotonin-CRF interaction on CRF-induced responses remains unclear. CRF infusion into the brain evokes a specific pattern of behavioural, endocrine and neuronal changes that resemble those following various forms of stress. The aim of the present study was to investigate the effects of serotonin depletion on acute CRF-induced c-fos expression, corticosterone levels and behavioural responses. Lateral ventricular (i.c.v.) infusion of CRF (250 pmol) resulted in a significant increase in grooming, corticosterone and c-fos mRNA in the PVN. Adequate and specific depletion of serotonin using 5,7-DHT did not alter these CRF-induced changes. These data suggest that acute responses induced by i.c.v. CRF are independent of basal levels of serotonin.

The aim of this trial was to assess the relative patient acceptability of two transdermal oestradiol patches used in treatment of oestrogen deficiency in postmenopausal women. Thirty-five hysterectomised postmenopausal women with no previous experience of transdermal oestradiol delivery systems received treatment with either once-weekly drug-in-adhesive (DIA) patches or twice-weekly reservoir patches for 4 weeks, and were then switched to the alternative treatment for a further 4 weeks. At the end of the study, the patients completed a questionnaire to assess their relative preference for a number of characteristics of the 2 transdermal systems and, where possible, their preference for transdermal compared with oral hormone replacement therapy. Thirty-one patients completed the study; four withdrew during treatment with the reservoir patch. The DIA patch was preferred for being 'easiest to remember to apply' by 80% of patients (p < 0.01), 'easiest to open' and 'easiest to apply' by 68% (p = 0.025), and as having 'best cosmetic appearance' by 65% (p = 0.05) and 'best overall skin adhesion' by 61% (p < 0.01). While 10% of patients rated the reservoir patch as 'least irritating to the skin' (p = 0.03), only one patient found this patch 'most comfortable to wear' (p < 0.01). The DIA patch was selected by 87% of patients as their preferred treatment overall (p = 0.001). Ninety-one per cent of 22 responding patients were at least as confident of treatment with transdermal patches as with oral hormone replacement therapy (p = 0.006) and 74 % of 27 responders preferred transdermal to oral treatment (p = 0.004). The DIA patch appears to be more acceptable to patients than the reservoir patch as a transdermal oestradiol delivery system for the treatment of postmenopausal oestrogen deficiency. Characteristics of the DIA patch which may account for improved patient acceptance include ease of remembering once-weekly patch application, improved cosmetic appearance and comfort, and better adhesion.