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Analysis of ammonium nitrate detonation destruction in Beirut city using geospatial techniques
Shiva Kumar,Ashvin Wickramasooriya,Sathya Dilini 대한공간정보학회 2022 Spatial Information Research Vol.30 No.6
Applications of geospatial techniques plays an important role in disaster management and mitigation. This study focuses to analyze how can geospatial technology could have been utilized to minimize the destruction created by the Ammonium Nitrate detonation in Beirut city. Firstly, the disaster impacts on the build-up area were demarcated using Google Earth-based survey, Remote Sensing, and ArcGIS applications. According to the analysis, it was identified that the Ammonium Nitrate detonation incident in the Beirut port has extensively damaged the built-up area within a 2 km buffer zone from the explosion. Among them, fully demolished constructions are bounded to a 1 km buffer area while partially damage and less damage to buildings were encompassed within 5 km from the epicenter of the incident. The Quantity Distance Mapping Tool results depicted more as similar results to the results obtained through the aforementioned geospatial techniques in post-disaster impact analysis. Therefore, proper planning to locate built-up areas considering vulnerable places away from the possible disaster-induced location utilizing spatial techniques like Quantity Distance Mapping Tool would be more effective in pre-disaster preparedness as we all live in a hidden catastrophic environment. Thus, lessons learned from this Ammonium Nitrate detonation incident of the Beirut city, especially the importance of risk assessment and adherence to precaution measures are needed in any chemical operation sites as well as chemical storing sites.
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Shiva Kumar,Jay Singh,Jogendra Siyag,Srikar Rambhatla 대한설비공학회 2020 International Journal of Air-Conditioning and Refr Vol.28 No.4
In hot climatic conditions, increased energy consumption toward cooling has led to the development of evaporative coolers. The performance of evaporative cooler depends on the various material and operating parameters. Type of material selected for cooling pad is the most important factor among them. In this study, various types of cooling pad materials have been discussed based on their potential benefits, influence on the cooling performance like characteristics wettability, porosity, water holding capacity and cost. It is seen that organic- and fiber-based materials have been extensively used, whereas the studies related to materials based on plastics and metals are limited. Ideal material properties to be possessed by a good pad material have been discussed. Prospects and future scope for further research have been identified. Hence, this review paper certainly throws some light on the selection criteria for a potential alternative evaporative cooling pad material that shows the maximum cooling performance and helps achieve sustainable cooling in buildings.
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DMSO‐ and Serum‐Free Cryopreservation of Wharton's Jelly Tissue Isolated From Human Umbilical Cord
Shivakumar, Sharath Belame,Bharti, Dinesh,Subbarao, Raghavendra Baregundi,Jang, Si‐,Jung,Park, Ji‐,Sung,Ullah, Imran,Park, Ji‐,Kwon,Byun, June‐,Ho,Park, Bong‐,Wook,Rho, G John Wiley and Sons Inc. 2016 Journal of cellular biochemistry Vol.117 No.10
<P><B>ABSTRACT</B></P><P>The facile nature of mesenchymal stem cell (MSC) acquisition in relatively large numbers has made Wharton's jelly (WJ) tissue an alternative source of MSCs for regenerative medicine. However, freezing of such tissue using dimethyl sulfoxide (DMSO) for future use impedes its clinical utility. In this study, we compared the effect of two different cryoprotectants (DMSO and cocktail solution) on post‐thaw cell behavior upon freezing of WJ tissue following two different freezing protocols (Conventional [−1°C/min] and programmed). The programmed method showed higher cell survival rate compared to conventional method of freezing. Further, cocktail solution showed better cryoprotection than DMSO. Post‐thaw growth characteristics and stem cell behavior of Wharton's jelly mesenchymal stem cells (WJMSCs) from WJ tissue cryopreserved with a cocktail solution in conjunction with programmed method (Prog‐Cock) were comparable with WJMSCs from fresh WJ tissue. They preserved their expression of surface markers, pluripotent factors, and successfully differentiated in vitro into osteocytes, adipocytes, chondrocytes, and hepatocytes. They also produced lesser annexin‐V‐positive cells compared to cells from WJ tissue stored using cocktail solution in conjunction with the conventional method (Conv‐Cock). Real‐time PCR and Western blot analysis of post‐thaw WJMSCs from Conv‐Cock group showed significantly increased expression of pro‐apoptotic factors (BAX, p53, and p21) and reduced expression of anti‐apoptotic factor (BCL2) compared to WJMSCs from the fresh and Prog‐Cock group. Therefore, we conclude that freezing of fresh WJ tissue using cocktail solution in conjunction with programmed freezing method allows for an efficient WJ tissue banking for future MSC‐based regenerative therapies. J. Cell. Biochem. 117: 2397–2412, 2016. © 2016 The Authors. <I>Journal of Cellular Biochemistry</I> published by Wiley Periodicals, Inc.</P>
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Shivakumar, Sharath Belame,Bharti, Dinesh,Jang, Si-Jung,Hwang, Sun-Chul,Park, Ji-Kwon,Shin, Jeong-Kyu,Byun, June-Ho,Park, Bong-Wook,Rho, Gyu-Jin Korean Society for Stem Cell Research 2015 International journal of stem cells Vol.8 No.2
<P><B>Objectives</B></P><P>To compare the effect of three different cryoprotectants on basic stem cell characteristics for the possibility of using well defined, dimethyl sulfoxide (DMSO) and serum free freezing solutions to cryopreserve human Wharton’s jelly-derived mesenchymal stem cells (WJMSCs) following controlled rate freezing protocol.</P><P><B>Methods</B></P><P>The mesenchymal stem cells isolated from human Wharton’s jelly were cryopreserved using 10% DMSO, 10% polyvinylpyrrolidone (PVP) and a cocktail solution comprising of 0.05 M glucose, 0.05 M sucrose and 1.5 M ethylene glycol following controlled rate freezing protocol. We investigated the post-thaw cell viability, morphology, proliferation capacity, basic stem cell characteristics, in vitro differentiation potential and apoptosis-related gene expression profile before and after cryopreservation.</P><P><B>Results</B></P><P>The cryoprotectant 10% DMSO has shown higher post-thaw cell viability of 81.2±0.58% whereas 10% PVP and cocktail solution have shown 62.87±0.35% and 72.2±0.23%, respectively at 0 h immediately thawing. The cell viability was further reduced in all the cryopreserved groups at 24 h later post-thaw culture. Further, the complete elimination of FBS in cryoprotectants has resulted in drastic reduction in cell viability. Cryopreservation did not alter the basic stem cell characteristics, plasticity and multipotency except proliferation rate. The expression of pro-apoptotic <I>BAX</I> and <I>p53</I> genes were higher whilst <I>p21</I> was lower in all the cryopreserved groups when compare to the control group of WJMSCs.</P><P><B>Conclusion</B></P><P>Although 10% DMSO has shown higher post-thaw cell viability compare to 10% PVP and cocktail solution, the present study indicates the feasibility of developing a well-defined DMSO free cryosolution which can improve storage and future broad range applications of WJMSCs in regenerative medicine without losing their basic stem cell characteristics.</P>
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Blends of Silicone Rubber and Liquid Crystalline Polymer
Shivakumar E.,Das C. K.,Pandey K. N.,Alam S.,N.Mathur G. The Polymer Society of Korea 2005 Macromolecular Research Vol.13 No.2
Blends of silicone rubber (VMQ) and liquid crystalline polymer (LCP) were prepared by the melt mixing technique. Mechanical, XRD, thermal and dynamic mechanical investigations are reported for the pure silicone rubber and blends. The mechanical properties, viz. the tensile strength, tear strength and elongation at break, of the silicone rubber decreased with the addition of LCP. The SEM study on the tensile fractured surface of the blends revealed that they had a two phase structure, and that the failure was mainly due to fiber pull out, which suggests that the VMQ and LCP are incompatible in all of the proportions examined in this study. However, the FTIR study shows that there was a partial interaction between the VMQ and LCP, but which may not be sufficient to grip the fibrils under the applied load. In the XRD analysis, it was observed that the crystalline structure of the silicone rubber deteriorated in the presence of LCP. The DMA study suggested that the storage modulus of the silicone rubber was improved with the addition of LCP, due to the high modulus of the LCP phase. The thermal stability of the silicone rubber was greatly reduced by the addition of LCP, due to the latter having a thermal stability lower than that of silicone rubber.
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BLOGS AS CONSUMERS SOURCE OF INFORMATION: AN EXPLORATORY STUDY
Shivakumar Krishnamurti,Ruchi Agarwal 글로벌지식마케팅경영학회 2014 Global Marketing Conference Vol.2014 No.7
The study examines the role of blogs as a source of information about products and services to consumers. A pre-designed questionnaire was used to collect the primary data (experiences) from the respondents. Data was collected from 190 respondents residing in and around the Emirates of Sharjah and Dubai of the United Arab Emirates. The collected data was analyzed with the help of statistical tools such as averages, percentages, factor analysis, Student’s t-test and Structural Equation model. The objectives of this study were to know; · The reasons why consumers of products and services are motivated to use blogs as a source of information, · whether the consumers of products and services share their views and experiences with other bloggers and · The respondents’ future intentions towards blogging. The study revealed the following: § A majority of respondents have the motivation to blog because they are willing to receive comments on what they post about services. § The blogs were convenient to search for information about services and products. § Respondents share information through blogging. For example, they may discuss the symptoms of a disease/-disorder experienced by someone, share information about ready to cook mix products and show keen interest in spending more time blogging in the future.
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BLOGS AS CONSUMERS SOURCE OF INFORMATION: AN EXPLORATORY STUDY
Shivakumar Krishnamurti,Ruchi Agarwal 글로벌지식마케팅경영학회 2014 Global Marketing Conference Vol.2014 No.9
The study examines the role of blogs as a source of information about products and services to consumers. A pre-designed questionnaire was used to collect the primary data (experiences) from the respondents. Data was collected from 190 respondents residing in and around the Emirates of Sharjah and Dubai of the United Arab Emirates. The collected data was analyzed with the help of statistical tools such as averages, percentages, factor analysis, Student’s t-test and Structural Equation model. The objectives of this study were to know;·The reasons why consumers of products and services are motivated to use blogs as a source of information, ·whether the consumers of products and services share their views and experiences with other bloggers and ·The respondents’ future intentions towards blogging. The study revealed the following: § A majority of respondents have the motivation to blog because they are willing to receive comments on what they post about services. § The blogs were convenient to search for information about services and products. § Respondents share information through blogging. For example, they may discuss the symptoms of a disease/-disorder experienced by someone, share information about ready to cook mix products and show keen interest in spending more time blogging in the future.
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Shivakumar Vignesh,Amna Subhan Butt,Mohamed Alboraie,Bruno Costa Martins,Alejandro Piscoya,Quang Trung Tran,Damien Tan Meng Yew,Shahriyar Ghazanfar,Pezhman Alavinejad,Edna Kamau,Ajay M Verma,Robin B M 대한소화기내시경학회 2021 Clinical Endoscopy Vol.54 No.5
Background/Aims: The coronavirus disease of 2019 (COVID-19) pandemic has impacted the training of medical traineesinternationally. The aim of this study was to assess the global impact of COVID-19 on endoscopy training from the perspective ofendoscopy trainers and to identify strategies implemented to mitigate the impact on trainee education. Methods: Teaching faculty of gastroenterology (GI) training programs globally were invited to complete a 36-question web-basedsurvey to report the characteristics of their training programs and the impact of COVID-19 on various aspects of endoscopytraining, including what factors decisions were based on. Results: The survey response rate was 52.6% (305 out of 580 individuals); 92.8% reported a negative impact on endoscopy training,with suspension of elective procedures (77.1%) being the most detrimental factor. Geographic variations were noted, with Europeanprograms reporting the lowest percentage of trainee participation in procedures. A higher proportion of trainees in the Americaswere allowed to continue performing procedures, and trainers from the Americas reported receiving the greatest support forendoscopy teaching. Conclusions: This study demonstrated that the COVID-19 pandemic has had a significant negative impact on GI endoscopytraining internationally, as reported by endoscopy trainers. Focus-optimizing endoscopy training and assessment of competenciesare necessary to ensure adequate endoscopy training.
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