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The effect of addition of poly(vinyl alcohol) on hydrothermal derived calcium phosphate cement has been studied. The precursors used to prepare the cement were calcium oxide (CaO) and ammonium dihydrogen phosphate (NH4H2PO4); the reaction was conducted in water at 80-100°C. To improve properties of CPC, poly(vinyl alcohol) (PVA) of 1wt% and 2wt% was added to the liquid phase of CPC and the results were compared to CPC without PVA addition. The addition of PVA was proved to bring remarkable effects on cohesion, setting time and mechanical strength of CPC which make it suitable physically for injectable bone filler applications.

Climate Models are the main tools available for developing projections of climate change in the future. Due to the inter-model differences in internal physics and the process of parameterization of the variables, it is essential to consider the range of projections from different models rather than depending on projection of one climate model only. In this study, multi-model ensemble for future projections of hydro-climatic parameters in terms of precipitation and temperature is developed on monthly resolution for each of the year from 2011 to 2100 with respect to a baseline period of 1971-2000 for Bangladesh. Simulations of four Global Climate Models (GCMs) named CGCM3.1, CCSM3, MIROC3.2 and HadGEM1 are applied for this purpose. An ensemble technique comprising Root Mean Square Error (RMSE) and Weight Factor has been thoroughly discussed. In line with this method, larger weight or preference is given to the GCM that has less error with respect to the observed temperature and precipitation values in the baseline. Prominent large scatters have been observed in the time-series plots for monthly multi-model ensemble precipitation, which resemble highly intensive and more inconsistent temporal precipitation pattern in future. In addition, mean surface temperature is likely to increase invariably in every month.

A detail study involving flow visualization, Laser Doppler Velocimeter (LDV) measurements and numerical prediction is presented. The visualization experiments revealed striking results of a pulsatile motion in the separated flow region associated with the formation and passage of large eddy structures. Measurements of mean velocities and turbulence intensity profiles across the separated flow field, provided information about the separated shear layer development and the recirculating flow pattern. The numerical predictions, obtained with a two-layer turbulence model in conjunction with the SIMPLE algorithm, failed to reproduce the coherent eddies and the pulsatile motion, but the mean velocities are reasonably reproduced.

A major dimension of climate change for south-Asia includes more erratic precipitation events, precipitation being highly intensive with large variability in individual months. Such aberrant characteristics of precipitation are gradually resulting consequences of multi-dimensional impacts. This paper demonstrates the spatial variation patterns of extreme precipitation conditions in Bangladesh, based on a precipitation-related climate change indicator called Precipitation Concentration Index (PCI). First, the monthly total precipitation records from 18 meteorological stations in Bangladesh are applied in calculating PCI within a 30-year study period of 1981-2010. Then the same index is simulated using a RCM projected precipitation values in the future time scale of 2071-2100. The spatial variation of PCI has been plotted applying GIS technique for three distinct seasons, exhibiting drastic seasonal deviations with significant regional differences between the two independent timesegments. Comparison of the two periods proves prominent increase of PCI values all over the country invariably in each season. Numerically, the RCM-based PCI denotes that precipitation during 2071-2100 might become uniform to moderately concentric in monsoon, little change of precipitation concentration is expected in premonsoon and strong irregular distribution might reach its pinnacle for dry months. Therefore, such simulation of precipitation concentration index can be effectively applied as a decision support tool for erosion and drought adaptation.

Temperature variability appears to be a major aspect as a consequence of extreme climatic changes. South Asian countries have been observing an increase in occurrence of extreme climate events in recent decades. This paper demonstrates the temporal as well as spatial variation patterns of extreme temperature conditions in the North-western region of Bangladesh, based on some temperature-related climate change indices involving Average Monthly Maximum and Minimum Temperature (Tmax and Tmin). The analysis of the paper is divided into two fold aspects. First, the average maximum and minimum temperature records from 5 meteorological stations situated in the North-western region are applied in calculating the indices, within a 30 year study period of 1971 to 2000. Then the same indices are calculated using a Regional Climate Model (RCM) temperature projections in the future time scale of 2071-2100. Comparison of these indices shows significant enhancement in temperature extremes in future times. The indices validate marked increase in Tmin value which influences the most in overall warming in North-western region both in the past reference period 1971-2000 as well as in 2071-2100. The spatial variation of these indices also shows drastic difference in the distribution of the indices in 2071-2100, compared to the climatological baseline of 1971-2000. Therefore, such simulation of indices on temperature extremes can play significant role in long-term planning for the preparedness of meteorological disasters and risk reduction in a region and to the globe as a whole.

Heat Index describes the combined effect of temperature and humidity on human body. This combined effect is causing a serious threat to the health of people because of the changing climate. With climate change, climate variability and thus the occurrence of heat waves is likely to increase. Evidence is emerging from the analysis of long-term climate records of an increase in the frequency and duration of extreme temperature events in all over Bangladesh particularly during summer. Summer season has prolonged while winters have become short in Bangladesh. Summers have become hotter and thus affecting the lives of the people engaged in outdoor activities during scorching sun hours. In 2003 around 62 people died due to heat wave across the country. In this paper Bangladesh is divided in four regions and heat index has been calculated from 1960 to 2010 in these regions of the country. The aim of this paper is to identify the spots most vulnerable to heat strokes and heat waves due to high heat index. The results show upward trend of heat index in almost all the regions of Bangladesh. The highest increase in heat index value has been observed in areas of South-west region and North-west Region. The highest change in average heat index has been found in Jessore by almost 5.50C., {"references":["Y. Aggarwal, B. M. Karan., B. N. Das., and R. K. Sinha., \"Prediction of\nHeat-Illness symptoms with the prediction of human vascular response\nin hot environment using rescuing condition,\" J Med Syst, vol. 32, pp.\n167-176, 2007.","S. Islam, Banglapedia, National Encyclopedia of Bangladesh, Board of\nEditors, Asiatic Society of Bangladesh, Dhaka, Bangladesh, Jan 2003.","Q. Z. Chaudhary and G. Rasul., \"Agro-Climatic classification of\nPakistan,\" Science Vision, vol. 9, no. 1-2, Jul-Dec 2003 & no. 3-4 (Jan-\nJun 2004), pp. 59-66.","T. L. Delworth, J. D. Mahlman., and T. R. Knutson, \"Changes in heat\nindex associated with CO2-indused global warming,\" Kluwer Academic\npublishers, Netherland, pp. 369-386, 1999.","L. P. Rothfusz, The heat index equation. Technical attachment,\nScientific Services Division NWS Southern Region Headquarters, Fort\nWorth, TX, SR 90-23, 1990.","S. Shahid, \"Spatial and temporal characteristics of droughts in the\nwestern part of Bangladesh,\" Hydrological Processes, vol. 22, issue 13,\nJun 2008, pp. 2235-2247 [First published online in Wiley InterScience,\nNov 2007].","R. G. Steadman, \"The assessment of sultriness. Part I: A temperature\nhumidity index based on human physiology and clothing science,\"\nJournal of Applied Meteorology, vol. 18, pp. 861- 873, Jul 1979.","R. G. Steadman, \"A universal scale of apparent temperature\", Journal of\nClimate and Applied Meteorology, vol. 23, pp. 1674 - 1687, 1984.","S.C. Sheridan and L.S. Kalkstein, \"Health watch/warning systems in\nurban areas\", World Resource Review, vol. 10, pp. 375-383. 1998."]}

Climate change has started to alter the way how climatic events take place on the earth. Occurrence and distribution of extreme climatic events are now more frequent and undoubtedly Bangladesh is experiencing the effects of climate change among which the extreme events manifest in a more evident and devastating way. This paper aims at eliciting evidences of the effect of climate change on the characteristics of cyclones of this region. Recent histories of cyclones that formed at the Bay of Bengal and made landfall on the coasts of Bangladesh, ranging from 1795 to 2009, were studied. Frequency of the cyclones has shown an increasing trend along with their intensity. Frequency of weaker cyclones is decreasing and although intensity of the weaker storm is rising, they are rising at a greater rate for the stronger storms and hence there will be large differences among the intensity of the future cyclones. Storm surges show a positive correlation with the intensity of the storms hence greater storm surges can be expected in the future. Storms tracks seem to remain unaltered for a long tract of time. These analyses implicate the necessity to decelerate climate change and also increase awareness among the highly dense population of the coastal regions of the developing countries to reduce damages due to such extreme events.

It is very much essential to comprehend the inter-relationship of future possible trend of precipitation with the water-stress problems in a small country like Bangladesh, since enormous challenges associated with water supply are already present in this region. A major dimension of climate change for Bangladesh includes the expectation of more intensive and variability of precipitation events in future times. There are a number of mathematical models of global circulation that indicate expectations of future climate scenarios. But one particular model does not produce a perfect projection of future climatology or observations as the inherent physics and associated underlying assumptions of the model-components might be different for different climate models. As such, it is best to combine several climate models to enable a choice to produce the most appropriate projection to be used in climate-scenario generation for a small geographical area. This paper features the development of Multi-Model combination of future precipitation projections for Bangladesh on monthly basis, for each of the year from 2011 to 2100, using both global and regional climate models. Four selected IPCC ensemble Global Climate Models (GCMs), namely CGCM3.1, CCSM3, MIROC3.2 and HadGEM1 as well as a Regional Climate Model (RCM) called PRECIS have been applied in this regard. The multi-model average precipitation changes for Bangladesh at SRES A1B scenario indicate that the precipitation might continue to increase in all the months in future years. Percentage of precipitation increment is expected to be quite higher for dry and pre-monsoon months compared to the monsoon season. Also, the large

The principal objective of this paper is to assess the variability of water level and flow of the Old Brahmaputra River. The water level and Discharge trend of the river has been assessed based on historical data to find the variability over time. Average monthly discharge at a particular gauge station of the river has been plotted for the duration of 1975 to 2006 for each of the month to have an observed flow trend characteristics through time. The trend lines show that the river has undergone a considerable declination during the period. The wet period show large fluctuations of flow in a range of 2200 to 500 m3/s with a sharp decreasing pattern. The wet period flow of Old Brahmaputra River shows relatively lower discharge almost in every alternative year and its declination is radical compared to dry period flow. Alike discharge pattern water level also shows decreasing trend. Frequent fluctuations of water level are observed during the period from 1991–2008 when it shows more dispersive nature in the monsoon months. This declination of water level is observed to be faster during 1991–2008 than 1973–1990.

Naphthalene, a widely used industrial and household chemical, has rarely been an agent of poisoning worldwide. Severe haemolysis from naphthalene poisoning is rare and can be a challenge to clinicians. We report a 22-year-old female, who accidentally ingested naphthalene mixed coconut oil and got admitted with recurrent vomiting, headache and passage of dark urine. Severe intravascular haemolysis with hypotension and neutrophilic leukocytosis was detected. She was treated with red blood cell transfusions, intravenous saline infusion and ascorbic acid.

Bangladesh Journal of Medicine, Vol 23 No 2, 2012, Page 48-49 DOI: http://dx.doi.org/10.3329/bjmed.v23i2.14982

Despite some controversy, selenomethionine (SeMet) mediated protection against colorectal carcinoma (CRC) might be a very promising non-cytotoxic option. However, responsive molecular targets and underlying mechanisms of SeMet mediated chemoprevention are still unclear. Our aim was to discover new targets of SeMet mediated chemoprevention in CRC using proteomics analysis. We found dietary SeMet supplementation before carcinoma initiation effectively suppressed polyp incidence and dysplastic lesions without any adverse effects. To determine chemopreventive targets of SeMet, we employed 2-dimensional gel electrophoresis based proteomics analysis in CRC mouse model. Pretreatment with SeMet apparently modulated the expression of 30 proteins with functions in major processes like chronic inflammation, oxidative-stress and apoptosis as discovered through pathway analysis with Pathway studio software.We validated four proteins selected from pathway analysis including prohibitin, purine nucleoside phosphorylase, annexin 2 and c-reactive protein by immuno-histochemistry. 8-hydroxy-2′-deoxyguanosine (8-OHdG), a known oxidative stress marker was decreased by SeMet treatment in CRC mice as seen by immunohistochemistry. Further network analysis was done among these new four validated proteins, 8-OHdG and colorectal cancer. These four proteins found by proteomics analysis might be considered as potential chemopreventive biomarkers of SeMet against colon cancer and can help develop and improve approaches in preventive, therapeutic and prognostic aspects. Citation Format: Md. Mujibur Rahman, Jee Young Kwon, Young Rok Seo. Identification of novel potential targets for selenomethionine-mediated chemoprevention in colorectal carcinoma mouse model via proteomics analysis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4861. doi:10.1158/1538-7445.AM2013-4861

J Shaheed Suhrawardy Med Coll ?Volume 2 Number 2 December 2010 ? Page 1 DOI: http://dx.doi.org/10.3329/jssmc.v2i2.12005

Powder forming at above ambient temperature with admixed lubricant to obtain the high quality green compacts is recently discovered, however the effects of sintering schedule to the mechanical properties and microstructures of final products are not explored yet. Therefore, a lab scale warm compaction rig is designed and fabricated to generate green compacts at different forming parameters. Iron ASC 100.29 is used as main powder constituent during this investigation. The defect-free green compacts were sintered in an argon gas fired furnace at different sintering schedule. The mechanical properties and microstructures of sintered parts were evaluated. The results revealed that the mechanical properties and microstructures of sintered products are affected by the forming temperature and sintering schedule. Therefore, the suitable forming temperature and sintering schedule are identified for the production of high quality components.

Friction force is generated during the generation of green compacts from metal powder, which obviously gives adverse effect to the mechanical properties and microstructure of the green compacts. In this study, fine carbon powder is used to minimize the interparticle as well as die wall frictions and as alloying element hence high density yet defect-free near-net shape or net shape mechanical components can be produced. Powder forming at elevated temperature is a relatively new technology hence the effect of carbon content is not fully explored yet. Therefore, a lab scale warm compaction rig is designed and fabricated which enabled the generation of green compacts at different forming load and temperature. The powder mass was prepared by mechanically mixing iron ASC 100.29 powder with different weight percent of fine carbon powder for different duration of time. The prepared powder mass was formed at different compaction temperature to generate green compacts for the purpose of mechanical testing and microstructure evaluation. The results revealed that the mechanical properties and microstructures of green compacts are affected by the carbon content, mixing time, as well as forming temperature. From this study, the suitable carbon content, mixing time, and forming temperature are identified for the production of high quality mechanical components.

This paper presents the failure investigation of high temperature superheater (HTS) tubes. Samples were collected from one of the coal fired power plants in Malaysia, namely, Stesen Janakuasa Sultan Azlan Shah, Manjung (Manjung Power Station). After eight years of non-continuous services of three boilers, welded support-clips were completely separated (detached) from (HTS) tubes, which caused the wall thinning. Collected failed samples were undergone several experimental investigations including visual inspection, thickness measurement, Vickers hardness testing, and microstructure evaluation. The results revealed that some cracks were initiated at the heat-affected zone (HAZ) and propagated partly throughout the weld metal. The estimation on operating temperature and operating hoop stress show indication that the specimen may experienced a hig operating temperature. Other findings confirmed that the detachment of welded support-clips from HTS tubes may also caused by dissimilar metal weld (DMW) failure due to the differences in expansion properties of parent metal and weld metal.

Global thresholding and local thresholding are two basic ways for image binarization. Global thresholding, not suitable for complex documents, may produce noise along the page borders when the intensity of an image is non-uniform. For degraded, noisy and illuminated images local thresholding is preferred. This paper presents a local thresholding scheme when the image is a collection of text, pictures, and background. It calculates the local mean and local contrast to separate the background from the foreground. Local contrast, not suitable for integral images, can be achieved by the differing local maximum, and local minimum intensity. The proposed approach doesn’t calculate standard deviation like much other local thresholding method but locally adapted with local mean and local contrast. This proposed algorithm has been tested with different types of images including ancient documents, noisy background, and pictures. The test results are compared with a global and some traditional local thresholding techniques in terms of MSE and PSNR. The comparison shows that the proposed method results improved PSNR and better extraction in OCR operation.