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The Kathmandu Valley in south Asia is considered as one of the global "hot spots" in terms of urban air pollution. It is facing severe air quality problems as a result of rapid urbanization and land use change, socioeconomic transformation, and high population growth. In this paper, we present the first full year (February 2013-January 2014) analysis of simultaneous measurements of two shortlived climate forcers/pollutants (SLCF/P), i.e., ozone (O3) and equivalent black carbon (hereinafter noted as BC) and aerosol number concentration at Paknajol, in the city center of Kathmandu. The diurnal behavior of equivalent BC and aerosol number concentration indicated that local pollution sources represent the major contributions to air pollution in this city. In addition to photochemistry, the planetary boundary layer (PBL) and wind play important roles in determining O3 variability, as suggested by the analysis of seasonal changes of the diurnal cycles and the correlation with meteorological parameters and aerosol properties. Especially during pre-monsoon, high values of O3 were found during the afternoon/evening. This could be related to mixing and entrainment processes between upper residual layers and the PBL. The high O3 concentrations, in particular during pre-monsoon, appeared well related to the impact of major open vegetation fires occurring at the regional scale. On a synoptic-scale perspective, westerly and regional atmospheric circulations appeared to be especially conducive for the occurrence of the high BC and O3 values. The very high values of SLCF/P, detected during the whole measurement period, indicated persisting adverse air quality conditions, dangerous for the health of over 3 million residents of the Kathmandu Valley, and the environment. Consequently, all of this information may be useful for implementing control measures to mitigate the occurrence of acute pollution levels in the Kathmandu Valley and surrounding area. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that occurs in two clinically indistinguishable forms: sporadic (SALS) and familial (FALS), the latter linked to several gene mutations, mostly inheritable in a dominant manner. Nearly 20% of FALS forms are linked to mutations in the Cu/Zn superoxide dismutase (SOD1) gene. Research on ALS relies on transgenic models and particularly on mice carrying a glycine-to-alanine conversion at the 93rd codon (G93A) of the hSOD1 gene. Although G93A transgenic mice have been widely employed in clinical trials and basic research, doubts have been recently raised from numerous reliable sources about their suitability to faithfully reproduce human disease. Besides, the scientific community has already foreseen swine as an attractive and alternative model to nonhuman primates for modeling human diseases due to closer anatomical, physiological and biochemical features of swine rather than rodents to humans. On this basis, we have produced the first swine ALS model by in vitro transfection of cultured somatic cells combined with somatic cell nuclear transfer (SCNT). To achieve this goal we developed a SOD1G93A (superoxide dismutase 1 mutated in Gly93-Ala) vector, capable of promoting a high and stable transgene expression in primary porcine adult male fibroblasts (PAF). After transfection, clonal selection and transgene expression level assessment, selected SOD1G93A PAF colonies were used as nuclei donors in SCNT procedures. SOD1G93A embryos were transferred in recipient sows, and pregnancies developed to term. A total of 5 piglets survived artificial hand raising and weaning and developed normally, reaching adulthood. Preliminary analysis revealed transgene integration and hSOD1G93A expression in swine tissues and 360° phenotypical characterization is ongoing. We believe that our SOD1G93A swine would provide an essential bridge between the fundamental work done in rodent models and the reality of treating ALS. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

We analysed the variability of equivalent black carbon (BC) and ozone (O3) at the global WMO/GAW station Nepal Climate Observatory-Pyramid (NCO-P, 5079 m a.s.l.) in the southern Himalayas, for evaluating the possible contribution of open vegetation fires to the variability of these short-lived climate forcers/pollutants (SLCF/SLCP) in the Himalayan region. We found that 162 days (9% of the data-set) were characterised by acute pollution events with enhanced BC and O3 in respect to the climatological values. By using satellite observations (MODIS fire products and the USGS Land Use Cover Characterization) and air mass back-trajectories, we deduced that 56% of these events were likely to be affected by emissions from open fires along the Himalayas foothills, the Indian Subcontinent and the Northern Indo-Gangetic Plain. These results suggest that open fire emissions are likely to play an important role in modulating seasonal and inter-annual BC and O3 variability over south Himalayas. [Copyright &y& Elsevier]

This work investigates the variability of ozone (O3), carbon monoxide (CO) and equivalent black carbon (BC) at the Italian Climate Observatory "O. Vittori" (ICO- OV), part of the Mt. Cimone global GAW-WMO station (Italy). For this purpose, ICO-OV observations carried out in the period January 2007-June 2009, have been analyzed and correlated with the outputs of the FLEXPART Lagrangian dispersion model to specifically evaluate the influence of biomass burning (BB) and anthropogenic emissions younger than 20 days. During the investigation period, the average O3, CO and BC at ICO-OV were 54±3ppb, 122±7ppb and 213±34 ng m-3 (mean±expanded uncertainty with p < 95 %), with clear seasonal cycles characterized by summer maxima and winter minima for O3 and BC and spring maximum and summer minimum for CO. According to FLEXPART outputs, BB impact is maximized during the warm months from July to September but appeared to have a significant contribution to the observed tracers only during specific transport events. We characterised in detail five "representative" events with respect to transport scales (i.e. global, regional and local), source regions and O3, CO and BC variations. For these events, very large variability of enhancement ratios O3/CO (from -0.22 to 0.71) and BC/CO (from 2.69 to 29.83 ng m-3 ppb-1) were observed. CO contributions related with anthropogenic emissions (COant) contributed to 17.4 % of the mean CO value observed at ICO-OV, with the warm months appearing particularly affected by transport events of air-masses rich in anthropogenic pollution. The proportion of tracer variability that is described by FLEXPART COant peaked to 37% (in May-September) for CO, 19% (in May-September) for O3 and 32 % (in January-April) for BC. During May-September, the analysis of the correlation among CO, O3 and BC as a function of the COant indicated that ICO-OV was influenced by air-masses rich in anthropogenic pollution transported from the regional to the global scale. On the other side, CO and O3 were negatively correlated during October-December, when FLEXPART does not show significant presence of re- cent anthropogenic emissions and only a few observations are characterized by enhanced BC. Such behaviour may be attributed to an ensemble of processes concurrent in enhancing O3 with low CO (upper troposphere/lower stratosphere intrusions) and to O3 titration by NO in polluted air-masses along with lower photochemical activity. An intermediate situation occurs in January-April when CO and O3 were almost uncorrelated and BC enhancements were associated to relatively old (10 days) anthropogenic emissions. [ABSTRACT FROM AUTHOR]

This work investigates the variability of ozone (O3), carbon monoxide (CO) and equivalent black carbon (BC) concentrations at the Italian Climate Observatory "O. Vittori" (ICO-OV), part of the Mt. Cimone global GAW-WMO station (Italy). For this purpose, ICO-OV observations carried out in the period January 2007-June 2009, have been analysed and correlated with the output of the FLEXPART Lagrangian dispersion model to specifically evaluate the influence of biomass burning (BB) and anthropogenic emissions younger than 20 days. During the investigation period, the average O3, CO and BC concentrations at ICO-OV were 54 ± 3 ppbv, 122 ± 7 ppbv and 213 ± 34 ngm-3 (mean ± expanded uncertainty with p < 95%), with clear seasonal cycles characterized by summer maxima and winter minima for O3 and BC and spring maximum and summer minimum for CO. According to FLEXPART output, BB impact is maximized during the warm months from July to September but appeared to have a significant contribution to the observed tracer concentrations only during specific transport events. We characterised in detail five major events with respect to transport scales (i.e. global, regional and local), source regions and O3, CO and BC variations. For these events, very large variability of enhancement ratios O3/CO (from -0.22 to 0.71) and BC/CO (from 2.69 to 29.83 ngm-3ppbv-1) were observed. CO related with anthropogenic emissions (COant) contributed to 17.4% of the mean CO value observed at ICO-OV, with the warm months appearing particularly affected by transport events of air-masses rich in anthropogenic pollution. The proportion of tracer variability that is described by FLEXPART COant peaked to 37% (in May-September) for CO, 19% (in May-September) for O3 and 32% (in January-April) for BC. During May-September, the analysis of the correlation among CO, O3 and BC as a function of the COant indicated that ICO-OV was influenced by air-masses rich in anthropogenic pollution transported from the regional to the global scale. On the other side, CO and O3 were negatively correlated during October-December, when FLEXPART does not show significant presence of recent anthropogenic emissions and only a few observations are characterized by enhanced BC. Such behaviour may be attributed to an ensemble of processes concurrent in enhancing O3 with low CO (upper troposphere/lower stratosphere intrusions) and O3 titration by NO in polluted air-masses along with lower photochemical activity. An intermediate situation occurs in January-April when CO and O3 were almost uncorrelated and BC enhancements were associated to relatively old (10 days) anthropogenic emissions. [ABSTRACT FROM AUTHOR]

Contents Somatic cell nuclear transfer (SCNT) was first developed in livestock for the purpose of accelerating the widespread use of superior genotypes. Although many problems still exist now after fifteen years of research owing to the limited understanding of genome reprogramming, SCNT has provided a powerful tool to make copies of selected individuals in different species, to study genome pluripotency and differentiation, opening new avenues of research in regenerative medicine and representing the main route for making transgenic livestock. Besides well-established methods to deliver transgenes, recent development in enzymatic engineering to edit the genome provides more precise and reproducible tools to target-specific genomic loci especially for producing knockout animals. The interest in generating transgenic livestock lies in the agricultural and biomedical areas and it is, in most cases, at the stage of research and development, with few exceptions that are making the way into practical applications. [ABSTRACT FROM AUTHOR]

This study presents two years of continuous observations of physical aerosol properties at the GAW-WMO global station "Nepal Climate Observatory -- Pyramid" (NCO-P, 27°57' N, 86° 48'E), sited at 5079 m a.s.l. in the high Himalayan Khumbu Valley (Nepal). Measurements of aerosol number size distribution, aerosol optical depth (AOD) and single scattering albedo (SSA) are analysed from March 2006 to February 2008. By studying the temporal variations of coarse (1 µm < Dp ≤10 µm) particle number concentration, 53 mineral Dust Transport Events (DTEs) are identified, accounting for 22.2% of the analysed data-set. Such events occurred prevalently during pre-monsoon (for 30.6% of the period) and winter (22.1%) seasons. However, uncommon cases of mineral dust transport are observed even during the monsoon season. The main sources of mineral dust reaching NCO-P are identified in the arid regions not far from the measurement site, i.e. from Tibetan Plateau, and Lot-Thar deserts, which account for 52% of the dust transport days. Moreover, a non-negligible contribution can be attributed to the Arabian Peninsula (17%) and the Indo-Gangetic Plains (16%), as indicated by three dimensional (3-D) back-trajectory analyses performed with LAGRANTO model. The observed DTEs lead to significant enhancements in the coarse aerosol number concentration (+513%) and coarse aerosol mass (+655%), as compared with average values observed in "dust-free" conditions (0.05 ± 0.11 cm-3 and 3.4 ± 3.7 µg m-3, respectively). During DTEs, SSA is higher (0.84-0.89) than on "dust-free" days (0.75-0.83), confirming the importance of this class of events as a driver of the radiative features of the regional Himalayan climate. Considering the dust events, a significant seasonal AOD increase (+37.5%) is observed in the post-monsoon, whereas lower increase (less than +11.1%) characterises the pre-monsoon and winter seasons confirming the influence of synoptic-scale mineral dust transports on the aerosol optical properties observed at NCO-P. [ABSTRACT FROM AUTHOR]

Aerosol mass and the absorbing fraction are important variables, needed to constrain the role of atmospheric particles in the Earth radiation budget, both directly and indirectly through CCN activation. In particular, their monitoring in remote areas and mountain sites is essential for determining source regions, elucidating the mechanisms of long range transport of anthropogenic pollutants, and validating regional and global models. Since March 2006, aerosol mass and black carbon concentration have been monitored at the Nepal Climate Observatory-Pyramid, a permanent high-altitude research station located in the Khumbu valley at 5079 m a.s.l. below Mt. Everest. The first twoyear averages of PM1 and PM1-10 mass were 1.94 μgm-3 and 1.88 μgm-3, with standard deviations of 3.90 μgm-3 and 4.45 μgm-3, respectively, while the black carbon concentration average is 160.5 ng m-3, with a standard deviation of 296.1 ng m-3. Both aerosol mass and black carbon show well defined annual cycles, with a maximum during the premonsoon season and a minimum during the monsoon. They also display a typical diurnal cycle during all the seasons, with the lowest particle concentration recorded during the night, and a considerable increase during the afternoon, revealing the major role played by thermal winds in influencing the behaviour of atmospheric compounds over the high Himalayas. The aerosol concentration is subject to high variability: in fact, as well as frequent "background conditions" (55% of the time) when BC concentrations are mainly below 100 ngm-3, concentrations up to 5 μgm-3 are reached during some episodes (a few days every year) in the premonsoon seasons. The variability of PM and BC is the result of both short-term changes due to thermal wind development in the valley, and long-range transport/synoptic circulation. At NCO-P, higher concentrations of PM1 and BC are mostly associated with regional circulation and westerly air masses from the Middle East, while the strongest contributions of mineral dust arrive from the Middle East and regional circulation, with a special contribution from North Africa and South-West Arabian Peninsula in post-monsoon and winter season. [ABSTRACT FROM AUTHOR]

This paper provides a detailed description of the atmospheric conditions characterizing the high Himalayas, thanks to continuous observations begun in March 2006 at the Nepal Climate Observatory-Pyramid (NCO-P) located at 5079ma.s.l. on the southern foothills of Mt. Everest, in the framework of ABC-UNEP and SHARE-Ev-K2-CNR projects. The work presents a characterization of meteorological conditions and air-mass circulation at NCO-P during the first two years of activity. The mean values of atmospheric pressure, temperature and wind speed recorded at the site were: 551 hPa, -3.0 °C, 4.7ms-1, respectively. The highest seasonal values of temperature (1.7 °C) and relative humidity (94%) were registered during the monsoon season, which was also characterized by thick clouds, present in about 80% of the afternoon hours, and by a frequency of cloud-free sky of less than 10%. The lowest temperature and relative humidity seasonal values were registered during winter, -6.3 °C and 22%, respectively, the season being characterised by mainly cloud-free sky conditions and rare thick clouds. The summer monsoon influenced rain precipitation (seasonal mean: 237 mm), while wind was dominated by flows from the bottom of the valley (S-SW) and upper mountain (N-NE). The atmospheric composition at NCO-P has been studied thanks to measurements of black carbon (BC), aerosol scattering coefficient, PM1, coarse particles and ozone. The annual behaviour of the measured parameters shows the highest seasonal values during the premonsoon (BC: 316.9 ngm-3, PM1: 3.9 μgm-3, scattering coefficient: 11.9Mm-1, coarse particles: 0.37 cm-3 and O3: 60.9 ppbv), while the lowest concentrations occurred during the monsoon (BC: 49.6 ngm-3, PM1: 0.6 μgm-3, scattering coefficient: 2.2Mm-1, and O3: 38.9 ppbv) and, for coarse particles, during the post-monsoon (0.07 cm-3). At NCO-P, the synoptic-scale circulation regimes present three principal contributions: Westerly, South-Westerly and Regional, as shown by the analysis of in-situ meteorological parameters and 5-day LAGRANTO back-trajectories. The influence of the brown cloud (AOD>0.4) extending over Indo-Gangetic Plains up to the Himalayan foothills has been evaluated by analysing the in-situ concentrations of the ABC constituents. This analysis revealed that brown cloud hot spots mainly influence the South Himalayas during the pre-monsoon, in the presence of very high levels of atmospheric compounds (BC: 1974.1 ngm-3, PM1: 23.5 μgm-3, scattering coefficient: 57.7Mm-1, coarse particles: 0.64 cm-3, O3: 69.2 ppbv, respectively). During this season 20% of the days were characterised by a strong brown cloud influence during the afternoon, leading to a 5-fold increased in the BC and PM1 values, in comparison with seasonal means. Our investigations provide clear evidence that, especially during the pre-monsoon, the southern side of the high Himalayan valleys represent a "direct channel" able to transport brown cloud pollutants up to 5000ma.s.l., where the pristine atmospheric composition can be strongly influenced. [ABSTRACT FROM AUTHOR]

The possible minimal range of reduction in snow surface albedo due to dry deposition of black carbon (BC) in the pre-monsoon period (March-May) was estimated as a lower bound together with the estimation of its accuracy, based on atmospheric observations at the Nepal Climate Observatory - Pyramid (NCO-P) sited at 5079ma.s.l. in the Himalayan region. A total BC deposition rate was estimated as 2.89 μgm-2 day-1 providing a total deposition of 266 μg m-2 for March-May at the site, based on a calculation with a minimal deposition velocity of 1.0×10-4 ms-1 with atmospheric data of equivalent BC concentration. Main BC size at NCO-P site was determined as 103.1-669.8 nm by correlation analyses between equivalent BC concentration and particulate size distributions in the atmosphere. The BC deposition from the size distribution data was also estimated. It was found that 8.7% of the estimated dry deposition corresponds to the estimated BC deposition from equivalent BC concentration data. If all the BC is deposited uniformly on the top 2-cm pure snow, the corresponding BC concentration is 26.0-68.2 μg kg-1, assuming snow density variations of 195-512 kgm-3 of Yala Glacier close to NCO-P site. Such a concentration of BC in snow could result in 2.0-5.2% albedo reductions. By assuming these albedo reductions continue throughout the year, and then applying simple numerical experiments with a glacier mass balance model, we estimated reductions would lead to runoff increases of 70-204mm of water. This runoff is the equivalent of 11.6-33.9% of the annual discharge of a typical Tibetan glacier. Our estimates of BC concentration in snow surface for pre-monsoon season is comparable to those at similar altitudes in the Himalayan region, where glaciers and perpetual snow regions begin, in the vicinity of NCO-P. Our estimates from only BC are likely to represent a lower bound for snow albedo reductions, because we used a fixed slower deposition velocity. In addition, we excluded the effects of atmospheric wind and turbulence, snow aging, dust deposition, and snow albedo feedbacks. This preliminary study represents the first investigation of BC deposition and related albedo on snow, using atmospheric aerosol data observed at the southern slope in the Himalayas. [ABSTRACT FROM AUTHOR]

We report chemical composition data for PM10 and PM1 from the Nepal Climate Observatory-Pyramid (NCO-P), the world's highest aerosol observatory, located at 5079m a.s.l. at the foothills of Mt. Everest. Despite its high altitude, the average PM10 mass apportioned by the chemical analyses is of the order of 6 μgm-3 (i.e., 10 μg/scm), with almost a half of this mass accounted for by organic matter, elemental carbon (EC) and inorganic ions, the rest being mineral dust. Organic matter, in particular, accounted for by 2.0 μgm-3 (i.e., 3.6 μg/scm) on a yearly basis, and it is by far the major PM10 component beside mineral oxides. Non-negligible concentrations of EC were also observed (0.36 μg/scm), confirming that light-absorbing aerosol produced from combustion sources can be efficiently transported up the altitudes of Himalayan glaciers. The concentrations of carbonaceous and ionic aerosols follow a common time trend with a maximum in the premonsoon season, a minimum during the monsoon and a slow recovery during the postmonsoon and dry seasons, which is the same phenomenology observed for other Nepalese Himalayan sites in previous studies. Such seasonal cycle can be explained by the seasonal variations of dry and moist convection and of wet scavenging processes characterizing the climate of north Indian subcontinent. We document the effect of orographic transport of carbonaceous and sulphate particles upslope the Himalayas, showing that the valley breeze circulation, which is almost permanently active during the out-of-monsoon season, greatly impacts the chemical composition of PM10 and PM1 in the high Himalayas and provides an efficient mechanism for bringing anthropogenic aerosols into the Asian upper troposphere (>5000m a.s.l.). The concentrations of mineral dust are impacted to a smaller extent by valley breezes and follow a unique seasonal cycle which suggest multiple source areas in central and south-west Asia. Our findings, based on two years of observations of the aerosol chemical composition, provide clear evidence that the southern side of the high Himalayas is impacted by transport of anthropogenic aerosols which constitute the Asian brown cloud. [ABSTRACT FROM AUTHOR]