Cosmogenic production of 37Ar in the context of the LUX-ZEPLIN experiment

We estimate the amount of 37Ar produced in natural xenon via cosmic ray-induced spallation, an inevitable consequence of the transportation and storage of xenon on the Earth's surface. We then calculate the resulting 37Ar concentration in a 10-tonne payload~(similar to that of the LUX-ZEPLIN experiment) assuming a representative schedule of xenon purification, storage and delivery to the underground facility. Using the spallation model by Silberberg and Tsao, the sea level production rate of 37Ar in natural xenon is estimated to be 0.024~atoms/kg/day. Assuming the xenon is successively purified to remove radioactive contaminants in 1-tonne batches at a rate of 1~tonne/month, the average 37Ar activity after 10~tonnes are purified and transported underground is 0.058--0.090~μBq/kg, depending on the degree of argon removal during above-ground purification. Such cosmogenic 37Ar will appear as a noticeable background in the early science data, while decaying with a 35~day half-life. This newly-noticed production mechanism of 37Ar should be considered when planning for future liquid xenon-based experiments

Development of cellulose based light weight polymer composites

Polymer matrix composites are used in most of the engineering structures today. This type of composite consists of reinforcing materials in polymer matrix. There is an increasing demand for environmentally friendly reinforcing materials to reduce the cost of traditional fibers. Cellulose is a natural polymer material. Cellulose is used as filler for the reinforcement of polymer materials. Microcrystalline cellulose is a branch of cellulose. Objective of this research is to develop and characterize polypropylene and microcrystalline cellulose based composite. Silane surface modification technique was used to modify the cellulose surface. Surface modified cellulose was mixed polypropylene materials with different compositions. Physical and mechanical properties of the developed product were measured by tensile, impact, hardness, density and water absorption tests. According to the experimental results, there is a gradual reinforcing effect with increase of cellulose' concentration. Water absorption and hardness results showed increase of water absorption and hardness with increase of cellulose concentration. There is a gradual reduction of density of the develop product with increase of cellulose concentration. 5 wt% sample showed the lowest density value and weight reduction is about 13%. This type of composite can be used for light weight strstructure design especially in load bearing applications

Aging populations and rural places: impacts on and innovations in land use planning

Recent demographic trends highlight the increased prevalence of older populations in rural America. The trends result from multiple demographic patterns, such as being ‘left behind’ as younger residents leave rural areas and the migration of older adults drawn to rural areas for amenity or lifestyle considerations. Policies aimed toward keeping older adults in their homes as long as feasible (the ‘aging in place’ movement) means Americans are residents in their communities for longer periods of time but with potential growing needs for assistance. The spatial and institutional organization of rural areas coincides to create significant challenges for an aging population. Rural areas lack many essential services for an older population, particularly health care. Transportation in rural areas is highly automobile-dependent, yet older adults face challenges with driving. Additionally, demographic trends indicate that older adults have fewer family members living near them. This chapter highlights innovations in land use planning and service provision for an aging population, emphasizing housing affordability and availability, multi-modal transportation options, recreational opportunities, and environmental sustainability. The chapter also describes governance issues shown to have success for organizations and land use planning agencies moving toward planning for an aging population

Novel bioinformatic developments for exome sequencing

Contains fulltext : 167997.pdf (publisher's version ) (Open Access)With the widespread adoption of next generation sequencing technologies by the genetics community and the rapid decrease in costs per base, exome sequencing has become a standard within the repertoire of genetic experiments for both research and diagnostics. Although bioinformatics now offers standard solutions for the analysis of exome sequencing data, many challenges still remain; especially the increasing scale at which exome data are now being generated has given rise to novel challenges in how to efficiently store, analyze and interpret exome data of this magnitude. In this review we discuss some of the recent developments in bioinformatics for exome sequencing and the directions that this is taking us to. With these developments, exome sequencing is paving the way for the next big challenge, the application of whole genome sequencing