Assessment of 137Cs in the Environment of Hetauda City, Nepal by In-Situ Gamma Ray Spectrometry

A significant amount of 137Cs radioactive fallout have been spread in the atmosphere due to nuclear weapon testing and nuclear reactor disasters. This fallout eventually settles on the Earth's surface, and because 137Cs has a long half-life, it remains in the environment for an extended period. Mapping the distribution of 137Cs is crucial, and this study aims to assess the radioactive deposition of 137Cs in the ground to establish baseline data for its distribution in the environment of Hetauda City, Nepal. Recently, Hetauda City has been designated as the capital city of the Bagmati province. To measure 137Cs deposition, portable (backpack) gamma ray spectrometer was used with a 0.347-liter NaI(Tl) detector.  Rapid measurement was carried out while walking at a pace of less than 2 km/h, and the distance between the detector and the ground was maintained at less than 1 m with the detector pointing downward. The surface activity of 137Cs was measured in the range of 0.003 to 2.382 kBq/m2, with an average value of 0.581 ± 0.343 kBq/m2. The spatial variability of 137Cs was found to be smooth in the area, and the mean annual effective dose calculated was 0.379 ± 0.224 µSv. The low dose rates and smooth spatial distribution of 137Cs in the environment indicate no contamination, and the trace amount present could be due to global fallout from weapons testing and nuclear accidents. The results were compared with previously reported values worldwide

Dataset from: Lapses in perceptual decisions reflect exploration.

Perceptual decision-makers often display a constant rate of errors independent of evidence strength. These “lapses” are treated as a nuisance arising from noise tangential to the decision, e.g. inattention or motor errors. Here, we use a multisensory decision task in rats to demonstrate that these explanations cannot account for lapses’ stimulus dependence. We propose a novel explanation: lapses reflect a strategic trade-off between exploiting known rewarding actions and exploring uncertain ones. We tested the model’s predictions by selectively manipulating one action’s reward magnitude or probability. As uniquely predicted by this model, changes were restricted to lapses associated with that action. Finally, we show that lapses are a powerful tool for assigning decision-related computations to neural structures based on disruption experiments (here, posterior striatum and secondary motor cortex). These results suggest that lapses reflect an integral component of decision-making and are informative about action values in normal and disrupted brain states

CRISPR-Cas9 Editing of Nitrate Transporter Gene, um03849, in Ustilago maydis

Ustilago maydis, the basidiomycete smut-fungus, can infect and cause tumors in corn plants. For this, mating between compatible haploid cells is important. The mating and subsequent dimorphic transition in U. maydis require starvation for nutrients such as nitrogen, in addition to pheromone-receptor interactions between compatible partners. In this research, the CRISPR-Cas9 gene-editing technique was used to create INDEL mutations (sequence insertion or deletion) in the nitrate transporter gene, um03849, in U. maydis. The gene was edited in mating compatible haploid strains 1/2 and 2/9. The phenotypes were characterized for the um03849 mutants as to growth ability, mating efficiency and pathogenesis. DNA sequence analysis confirmed isolates with 3 bp-deletion, 19 bp-deletion and 2 bp-substitution in the 1/2 mating strain, while a 3 bp-deletion and a 66 bp-insertion were found in independent isolates of the 2/9 strain. The matting assay results showed that any forms of mutation in um03849 in U. maydis didn’t affect mating with its compatible partner, as assessed by “fuzz” on charcoal media. However, the growth of mutated 1/2 strains was affected when grown in a medium with nitrate or nitrite as a source of nitrogen. With respect to host plant pathogenesis, the 1/2 strain with 2 bp substitution crossed with 2/9 WT strain showed dramatically reduced infection. Base substitution in the 1/2 strain resulted in arginine being substituted for lysine. Thus, this study suggests that the nitrate transporter affects the growth and pathogenesis of U. maydis on its host plant in a manner dependent on the 1/2 background.https://ir.library.louisville.edu/uars/1006/thumbnail.jp

Projecting Nepal's Demographic Future- How to deal with spatial and demographic heterogeneity

This Working Paper outlines the efforts of the cooperation between researchers at IIASA’s World Population Program and the Ministry of Health and Population, Nepal to conduct small-area population projections on Village Development Committee and Municipality levels for Nepal from 2011 to 2031. In order to fulfil this aim it was necessary to compile, harmonize and estimate small-area population data based on the latest census and survey data. Due to the lack of comprehensive fine-grained data on the demographic determinants fertility, mortality, and migration we estimate those with different methodological approaches like the Child-Women-Ratio or mortality corrections. In recent time, internal and international migration has become the most common of the three demographic components; therefore, most efforts went into estimating the rates of migration flows to and from several directions. The creation of this small-area fertility, mortality and migration data by age and sex enables us to apply the well-known cohort component method in a multi-state framework (each district as a state) and to create reasonable scenarios on the prospective population development for Nepal on regional and local level. This will help national, regional and local actors and policymakers to set appropriate measures to steer and adapt to the future characteristics of the Nepalese society on all administrative levels

The dissimilar chemical composition of the planet-hosting stars of the XO-2 binary system

Using high-quality spectra of the twin stars in the XO-2 binary system, we have detected significant differences in the chemical composition of their photospheres. The differences correlate strongly with the elements' dust condensation temperature. In XO-2N, volatiles are enhanced by about 0.015 dex and refractories are overabundant by up to 0.090 dex. On average, our error bar in relative abundance is 0.012 dex. We present an early metal-depletion scenario in which the formation of the gas giant planets known to exist around these stars is responsible for a 0.015 dex offset in the abundances of all elements while 20 M_Earth of non-detected rocky objects that formed around XO-2S explain the additional refractory-element difference. An alternative explanation involves the late accretion of at least 20 M_Earth of planet-like material by XO-2N, allegedly as a result of the migration of the hot Jupiter detected around that star. Dust cleansing by a nearby hot star as well as age or Galactic birthplace effects can be ruled out as valid explanations for this phenomenon.Comment: ApJ, in press. Complete linelist (Table 3) available in the "Other formats -> Source" downloa

Field, Frequency, and Temperature Dependencies of the Surface Resistance of Nitrogen Diffused Niobium Superconducting Radio Frequency Cavities

We investigate the rf performance of several single-cell superconducting radio-frequency cavities subjected to low temperature heat treatment in nitrogen environment. The cavities were treated at temperature 120–165 °C for an extended period of time (24–48 h) either in high vacuum or in a low partial pressure of ultrapure nitrogen. The improvement in 0 with a rise was observed when nitrogen gas was injected at ∼300 °C during the cavity cooldown from 800 °C and held at 165 °C, without any degradation in accelerating gradient over the baseline performance. The treatment was applied to several elliptical cavities with frequency ranging from 0.75 to 3.0 GHz, showing an improved quality factor as a result of low temperature nitrogen treatments. The rise feature is similar to that achieved by nitrogen alloying Nb cavities at higher temperature, followed by material removal by electropolishing. The surface modification was confirmed by the change in electronic mean free path and tuned with the temperature and duration of heat treatment. The decrease of the temperature-dependent surface resistance with increasing rf field, resulting in a rise, becomes stronger with increasing frequency and decreasing temperature. The data suggest a crossover frequency of ∼0.95  GHz above that the rise phenomenon occurs at 2 K. Some of these results can be explained qualitatively with an existing model of intrinsic field-dependence of the surface resistance with both equilibrium and nonequilibrium quasiparticle distribution functions. The change in the slope below 0.95 GHz may result from masking contribution of trapped magnetic flux to the residual surface resistance

1st International Conference on Bioresource Technology for Bioenergy, Bioproducts & Environmental Sustainability (BIORESTEC)

With growing global interest in bioenergy, biobased product and environmental sustainability, the first International Conference on Bioresource Technology for Bioenergy, Bioproducts & Environmental Sustainability (BIORESTEC) was organized from October 2326, 2016 in Sitges, Barcelona in Spain. The conference was organized in association with Elseviers premier journal Bioresource Technology (BITE), with an aim to provide a shared forum for researchers, academicians, industries, and policymakers, to discuss the current state-of-the-art and the emerging trends in biotechnology, bioenergy, and biobased products. The 1st BIORESTEC conference received tremendous response from all over the globe with 754 abstracts submitted. The scientific committee consisted of 13 eminent scientists from 11 countries. The committee then screened and selected 54 abstracts for oral and 166 abtsracts for poster presentations. Besides, there were 19 invited speakers from 14 countries. Apart from the scientific presentations, a workshop on How to write a scientific paper and get published was also organized for early career researchers by Elsevier. This special issue of the journal contain 29 papers (all presented at the BIORESTEC conference) after peer-review process. These papers broadly cover areas such as biomass pretreatment, algal and lignocellulose biorefinery, biological waste treatment, white biotechnology and biomass policies, LCA and techno-economics and classified as below.info:eu-repo/semantics/publishedVersio

Note: Scalable Multiphoton Coincidence-counting Electronics

We present a multichannel coincidence-counting module for use in quantum optics experiments. The circuit takes up to four transistor–transistor logic pulse inputs and counts either twofold, threefold, or fourfold coincidences, within a user-selected coincidence-time window as short as 12 ns. The module can accurately count eight sets of multichannel coincidences, for input rates of up to 84 MHz. Due to their low cost and small size, multiple modules can easily be combined to count arbitrary M-order coincidences among N inputs