experimental study on properties of natural soils treated with cement kiln dust

Soil improvement by the addition of chemical or cementitious additives is emerged as a remarkable solution to provide a suitable ground for infrastructure construction. Previous studies have used several additives together with the cement kiln dust (CKD) worldwide. Using CKD as an additive would also lower the solid waste problem in cement industry, thus CKD can be used effectively as a sustainable solution. To illustrate the efficacy of CKD in soil improvement, this study treated two natural soils with several proportions of CKD for various curing periods. Extensive laboratory tests were carried out to depict the variation of unconfined compressive strength by treating the natural soils with CKD at various proportion. Samples were prepared for natural soils with and without CKD. Similarly, tests were carried out in dry and immersed conditions. The sum of results highlights that significant increment in the unconfined compressive strength is achieved when CKD is used as an additive in natural soil. Keywords: Engineering properties, Unconfined compressive strength, Natural soil, Cement kiln dus

Modified atmosphere packaging of capsicum for extending shelf life under coolbot condition

Capsicum is one of the high value vegetable crops in Nepal. Its demand in kitchen is increasing due to urbanization and increased awareness on its health benefit. Its commercial cultivation has been started in protected as well as open field conditions. It fetches higher price in market but has very short storage life under ordinary storage condition. An experiment was carried out to evaluate the modified atmosphere packaging (MAP) on extension of shelf-life of capsicum fruit. Fruit were harvested at full mature stage with smooth and shiny appearance from farmer's field grown under protected condition at Chitwan, Nepal. The fruits were brought to postharvest laboratory of National Horticulture Research Centre, pre-cooled for 3-4 hours, cleaned with muslin cloth and packed in 25 micron Low Density Polyethylene (LDPE) packaging with different number of pinhole sized perforations viz. without pinholes, eight pinholes, sixteen pinholes, twenty four pinholes and control (without MAP). The study was conducted in completely randomized block design with five treatments and four replications. Fruits were kept at coolbot storage (9.8+2 ºC, 86+5% RH) till 30 days and analyzed for various postharvest physical, chemical and physiological parameters at every 10, 20 and 30 days of storage. The result showed that LDPE packaging influenced on reduction of physiological loss in weight (PLW), spoilage loss, ascorbic acid content, TA, freshness, firmness and shelf life. The modified atmosphere packaging (MAP) without pinholes showed the minimum PWL (1.71%) and the optimum fruit freshness (4.76) but the spoilage loss was the maximum (14%). Among the packaging, MAP with 8 pinholes maintained majority of postharvest quality retention with reduced physiological loss in weight (4.15 %), freshness (4.5) and spoilage loss (2%)

Geohazard vulnerability and condition assessment of the Asian highway AH-48 in Bhutan

Transport networks are frequently exposed to geohazards, and losses can be observed frequently by notable disaster incidents such as landslides, earthquakes, and floods. Although losses due to natural disasters are frequently reported, limited attention is paid to assess the condition of strategic road networks in the Himalayas. Thus, to fulfill this gap, this study performs condition assessment of Asian Highway AH-48 in Bhutan and develops a system to rate the performance level of road assets. The assessment is conducted along a 157.6 km stretch of AH-48. The sum of findings highlights that about 55% of the road assets along the AH-48 are highly vulnerable to geohazards. Drains are observed to be the most vulnerable, with 52% drains lying below the standard rating among the considered assets followed by retaining walls and pavement. Landslide vulnerability function for highways that are situated in mountain regions is developed using the newly proposed landslide intensity scale. The sum of findings highlights that the Himalayan roads will be affected mostly by landslides and the drainage system is the most affected road asset showing the least serviceability among the common road assets

Homologous Recombination Repair Factors Rad51 and BRCA1 Are Necessary for Productive Replication of Human Papillomavirus 31

ABSTRACT High-risk human papillomavirus 31 (HPV31)-positive cells exhibit constitutive activation of the ATM-dependent DNA damage response (DDR), which is necessary for productive viral replication. In response to DNA double-strand breaks (DSBs), ATM activation leads to DNA repair through homologous recombination (HR), which requires the principal recombinase protein Rad51, as well as BRCA1. Previous studies from our lab demonstrated that Rad51 and BRCA1 are expressed at high levels in HPV31-positive cells and localize to sites of viral replication. These results suggest that HPV may utilize ATM activity to increase HR activity as a means to facilitate viral replication. In this study, we demonstrate that high-risk HPV E7 expression alone is sufficient for the increase in Rad51 and BRCA1 protein levels. We have found that this increase occurs, at least in part, at the level of transcription. Studies analyzing protein stability indicate that HPV may also protect Rad51 and BRCA1 from turnover, contributing to the overall increase in cellular levels. We also demonstrate that Rad51 is bound to HPV31 genomes, with binding increasing per viral genome upon productive replication. We have found that depletion of Rad51 and BRCA1, as well as inhibition of Rad51's recombinase activity, abrogates productive viral replication upon differentiation. Overall, these results indicate that Rad51 and BRCA1 are required for the process of HPV31 genome amplification and suggest that productive replication occurs in a manner dependent upon recombination. IMPORTANCE Productive replication of HPV31 requires activation of an ATM-dependent DNA damage response, though how ATM activity contributes to replication is unclear. Rad51 and BRCA1 play essential roles in repair of double-strand breaks, as well as the restart of stalled replication forks through homologous recombination (HR). Given that ATM activity is required to initiate HR repair, coupled with the requirement of Rad51 and BRCA1 for productive viral replication, our findings suggest that HPV may utilize ATM activity to ensure localization of recombination factors to productively replicating viral genomes. The finding that E7 increases the levels of Rad51 and BRCA1 suggests that E7 contributes to productive replication by providing DNA repair factors required for viral DNA synthesis. Our studies not only imply a role for recombination in the regulation of productive HPV replication but provide further insight into how HPV manipulates the DDR to facilitate the productive phase of the viral life cycle

Sensitivity analysis of input ground motion on surface motion parameters in high seismic regions:a case of Bhutan Himalaya

Historical earthquakes demonstrate that strong motion characteristics and local soil condition, when coupled, significantly influence seismic site response. Interestingly, most of the Himalayan earthquakes depicted anomalous behavior per the site conditions historically. Being one of the most active seismic regions on earth, the eastern fringe of the Himalaya has observed many devastating earthquakes together with non-uniform damage scenarios. To quantify such anomalies, we evaluate surface motion parameters for a soft soil deposit located in the city of Phuentsholing in western Bhutan. Using one-dimensional site response analysis, the sensitivity of ground motion variation is estimated. This study accounts for the earthquakes of moment magnitudes 6.6 to 7.5 with a wide variation in peak ground acceleration (PGA). To dissect the characteristics of six inputted ground motions on eight local ground conditions, a sensitivity analysis is performed statistically. The statistical correlation of the response datasets and the linear regression model of the bedrock outcrop and the surface motion spectral acceleration along the stratified depth are examined to quantify the variation in surface motion parameters. The results highlight that the strong motions with PGA greater than 0.34 g demonstrate greater sensitivity, leading to some anomalies in response parameters, especially amplification. Similar results were obtained for the low PGA range (<0.1 g)

Foodborne Outbreak Investigation in a Festival at Panchkhal Municipality of Kavrepalanchok District in Central Nepal

Background: On September 2018, cluster of gastrointestinal cases following feast of Teej Festival was reported in Panchkhal Municipality of Kavrepalanchok, Nepal. The outbreak was investigated to identify the possible source of infection, causative agent and guide local control measures for prevention and control of the outbreak. Methods: Demographic and clinical details were collected from the cases, and the outbreak was described by time, place and person. Fourteen key informant interviews were conducted to assess the probable cause of infection, practice of food handling and preparation, source of drinking water. Semi-structured questionnaires were used to collect data from the cases. Blood examination, stool examination and culture and hepatitis serological test were done. Samples from wells and ponds were collected and microbiological tests were done in National Public Health Laboratory. Results: A total of 452 cases were identified with gastrointestinal illness and no reported deaths. All the affected population had taken food from the same place during the festival where children being more affected. Two stool samples detected Entamoeba Histolytica and some showed pus cells with no cyst or ova of organisms. Stool culture was negative. No definitive source of infection detected but was suspected to be due to improper food handling. Conclusion: This investigations confirmed the food borne outbreak in Panchkhal Municipality. The definitive causative agent of the foodborne outbreak was not identified. Proper and timely response to the outbreak is of utmost important, and can reduce the severity of the illness and halt further spread of the epidemics

Assessing the prospects of transboundary multihazard dynamics:The case of Bhotekoshi—Sunkoshi watershed in Sino—Nepal border region

The impacts of multihazards have become more pronounced over the past few decades globally. Multiple hazards and their cascading impacts claim enormous losses of lives, livelihoods, and built environment. This paradigm prompts integrated and multidisciplinary perspectives to identify, characterize, and assess the occurrence of multihazards and subsequently design counter-measures considering impending multihazard scenarios at the local level. To this end, we considered one of the most egregious transboundary watersheds, which is regarded as a multihazard hotspot of Nepal, to analyze the underlying causes and cascade scenarios of multihazards, and their associated impacts. In this paper, geophysical, hydrometeorological, and socioeconomic perspectives are formulated to characterize the watershed from the dimension of susceptibility to multihaz-ard occurrence. To characterize the complex dynamics of transboundary multihazard occurrence, insights have been presented from both the Nepali and the Chinese sides. Individual case studies and the interrelation matrix between various natural hazards are also presented so as to depict mul-tihazard consequences in the transboundary region. The sum of the observations highlights that the watershed is highly vulnerable to a single as well as multiple natural hazards that often switch to disasters

Multi-Hazard Risk Assessment of Kathmandu Valley, Nepal

Natural hazards are complex phenomena that can occur independently, simultaneously, or in a series as cascading events. For any particular region, numerous single hazard maps may not necessarily provide all information regarding impending hazards to the stakeholders for preparedness and planning. A multi-hazard map furnishes composite illustration of the natural hazards of varying magnitude, frequency, and spatial distribution. Thus, multi-hazard risk assessment is performed to depict the holistic natural hazards scenario of any particular region. To the best of the authors’ knowledge, multi-hazard risk assessments are rarely conducted in Nepal although multiple natural hazards strike the country almost every year. In this study, floods, landslides, earthquakes, and urban fire hazards are used to assess multi-hazard risk in Kathmandu Valley, Nepal, using the Analytical Hierarchy Process (AHP), which is then integrated with the Geographical Information System (GIS). First, flood, landslide, earthquake, and urban fire hazard assessments are performed individually and then superimposed to obtain multi-hazard risk. Multi-hazard risk assessment of Kathmandu Valley is performed by pair-wise comparison of the four natural hazards. The sum of observations concludes that densely populated areas, old settlements, and the central valley have high to very high level of multi-hazard risk