Background:Children suffering from beta-thalassemia major require repeated blood transfusions which may be associated with dangers like iron overload and contraction of infections such as HIV, HCV, and HBsAg which ultimately curtail their life span. On the other hand, inadequate transfusions lead to severe anemia and general fatigue and debility.Materials and Methods:Data were obtained from 142 beta-thalassemia major patients aged 3 years or more receiving regular blood transfusions at a transfusion centre in Western India from 1 April 2009 to 30 June 2009. The clinical data and laboratory results were subsequently analyzed.Results:Of the 142 patients, 76 (53.5%) were undertransfused (mean Hb <10 gm%). 96 (67%) of the patients were taking some form of chelation therapy but out of them only 2 (2%) were adequately chelated (S. ferritin <1000 ng/ml). 5 (3.5%) of the patients were known diabetics on insulin therapy. 103 (72%) of the patients were retarded in terms of growth. The prevalence of transfusion-transmitted infections (TTIs) such as HCV, HIV, and HBsAg was respectively 45%, 2%, and 2%, with the prevalence of HCV being significantly more than the general population. The HCV prevalence showed positive correlation with the age of the patients and with the total no of blood transfusions received. As many as 15% (6 out of 40) children who were born on or after 2002 were HCV positive despite the blood they received being subjected to screening for HCV.Conclusions:The study suggests the need to step up the transfusions to achieve hemoglobin goal of 10 gm% (as per the moderate transfusion regimen) and also to institute urgent and effective chelation measures with the aim of keeping serum ferritin levels below 1000 ng/ml to avoid the systemic effects of iron overload. In addition, strict monitoring of the children for endocrinopathy and other systemic effects of iron overload should be done. Rigid implementation of quality control measures for the ELISA kits used to detect HCV in donor blood needs to be done urgently. Alternately, more sensitive and specific measures (like NAT testing) should be employed for detection of HCV. In the absence of a definitive cure accessible and available to all patients, strict implementation of the above suggested measures will go a long way in improving the quality (and quantity) of life in patients of beta-thalassemia major.

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This study presents a theoretical investigation of the effect of the aerosol vertical distribution on the aerosol radiative effect (ARE). Four aerosol composition models (dust, polluted dust, pollution and pure scattering aerosols) with varying aerosol vertical profiles are incorporated into a radiative transfer model. The simulations show interesting spectral dependence of the ARE on the aerosol layer height. ARE increases with the aerosol layer height in the ultraviolet (UV: 0.25–0.42 μm) and thermal-infrared (TH-IR: 4.0–20.0 μm) regions, whereas it decreases in the visible-near infrared (VIS-NIR: 0.42–4.0 μm) region. Changes in the ARE with aerosol layer height are associated with different dominant processes for each spectral region. The combination of molecular (Rayleigh) scattering and aerosol absorption is the key process in the UV region, whereas aerosol (Mie) scattering and atmospheric gaseous absorption are key players in the VIS-NIR region. The longwave emission fluxes are controlled by the environmental temperature at the aerosol layer level. ARE shows maximum sensitivity to the aerosol layer height in the TH-IR region, followed by the UV and VIS-NIR regions. These changes are significant even in relatively low aerosol loading cases (aerosol optical depth ∼0.2–0.3). Dust aerosols are the most sensitive to altitude followed by polluted dust and pollution in all three different wavelength regions. Differences in the sensitivity of the aerosol type are explained by the relative strength of their spectral absorption/scattering properties. The role of surface reflectivity on the overall altitude dependency is shown to be important in the VIS-NIR and UV regions, whereas it is insensitive in the TH-IR region. Our results indicate that the vertical distribution of water vapor with respect to the aerosol layer is an important factor in the ARE estimations. Therefore, improved estimations of the water vapor profiles are needed for the further reduction in uncertainties associated with the ARE estimation.

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Accurate information about aerosol vertical distribution is needed to reduce uncertainties in aerosol radiative forcing and its effect on atmospheric dynamics. The present study deals with synergistic analyses of aerosol vertical distribution and aerosol optical depth (AOD) with meteorological variables using multisatellite and ground‐based remote sensors over Kanpur in central Indo‐Gangetic Plain (IGP). Micro‐Pulse Lidar Network‐derived aerosol vertical extinction (σ) profiles are analyzed to quantify the interannual and daytime variations during monsoon onset period (May–June) for 2009–2011. The mean aerosol profile is broadly categorized into two layers viz., a surface layer (SL) extending up to 1.5 km (where σ decreased exponentially with height) and an elevated aerosol layer (EAL) extending between 1.5 and 5.5 km. The increase in total columnar aerosol loading is associated with relatively higher increase in contribution from EAL loading than that from SL. The mean contributions of EALs are about 60%, 51%, and 50% to total columnar AOD during 2009, 2010, and 2011, respectively. We observe distinct parabolic EALs during early morning and late evening but uniformly mixed EALs during midday. The interannual and daytime variations of EALs are mainly influenced by long‐range transport and convective capacity of the local emissions, respectively. Radiative flux analysis shows that clear‐sky incoming solar radiation at surface is reduced with increase in AOD, which indicates significant cooling at surface. Collocated analysis of atmospheric temperature and aerosol loading reveals that increase in AOD not only resulted in surface dimming but also reduced the temperature (∼2–3°C) of lower troposphere (below 3 km altitude). Radiative transfer simulations indicate that the reduction of incoming solar radiation at surface is mainly due to increased absorption by EALs (with increase in total AOD). The observed cooling in lower troposphere in high aerosol loading scenario could be understood as a dynamical feedback of EAL‐induced stratification of lower troposphere. Further, the observed radiative effect of EALs increases the stability of the lower troposphere, which could modulate the large‐scale atmospheric dynamics during monsoon onset period. These findings encourage follow‐up studies on the implication of EALs to the Indian summer monsoon dynamics using numerical models.

The effects of absorbing aerosols on the atmospheric radiation budget and dynamics over the eastern Mediterranean region are studied using satellites and ground-based observations, and radiative transfer model calculations, under summer conditions. Climatology of aerosol optical depth (AOD), single scattering albedo (SSA) and size parameters were analyzed using multiyear (1999-2012) observations from Moderate Resolution Imaging Spectroradiometer (MODIS), Multi-angle Imaging SpectroRadiometer (MISR) and AErosol RObotic NET-work (AERONET). Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP)-derived aerosol vertical distributions and their classifications are used to calculate the AOD of four dominant aerosol types: dust, polluted dust, polluted continental, and marine aerosol over the region. The seasonal mean (June-August 2010) AODs are 0.22 +/- 0.02, 0.11 +/- 0.04, 0.10 +/- 0.04 and 0.06 +/- 0.01 for polluted dust, polluted continental, dust and marine aerosol, respectively. Changes in the atmospheric temperature profile as a function of absorbing aerosol loading were derived for the same period using observations from the AIRS satellite. We inferred heating rates in the aerosol layer of similar to 1.7 +/- 0.8 K day(-1) between 925 and 850 hPa, which is attributed to aerosol absorption of incoming solar radiation. Radiative transfer model (RTM) calculations show significant atmospheric warming for dominant absorbing aerosol over the region. A maximum atmospheric forcing of +16.7 +/- 7.9 W m(-2) is calculated in the case of polluted dust, followed by dust (+9.4 +/- 4.9 W m(-2)) and polluted continental (+6.4 +/- 4.5 W m(-2)). RTM-derived heating rate profiles for dominant absorbing aerosol show warming of 0.1-0.9 K day(-1) in the aerosol layer (<3.0 km altitudes), which primarily depend on AODs of the different aerosol types. Diabatic heating due to absorbing aerosol stabilizes the lower atmosphere, which could significantly reduce the atmospheric ventilation. These conditions can enhance the "pollution pool" over the eastern Mediterranean

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