601 research outputs found
First record of Chilapata rain-pool frog Minervarya chilapata Ohler, Deuti, Grosjean, Paul, Ayyaswamy, Ahmed & Dutta, 2009 (Anura, Dicroglossidae) from Nepal
Chilapata rain-pool frog (Minervarya chilapata) was described in 2009 from the Chilapata Reserve Forest of West Bengal, India. Here, we report the occurrence of M. chilapata for the first time from Morang district, Nepal, based on acoustic and morphological characters such as the presence of a distinct white line in the upper lip, small size (snout-vent length 18 to 26 mm), pointed snout and presence of dorso-lateral black patch. The nearest record of Chilapata rain-pool frog in Nepal from Pathari-Kanepokhari forest, Morang district, Nepal is ca.182 km west of its type locality Chilapata Reserve Forest, Jalpaiguri district, West Bengal, India. We also report the occurrence of M. chilapata from Barandabhar Biological Corridor, Chitwan National Park, Nepal based on a photographic record. The International Union for Conservation of Nature (IUCN) has listed the species as Data Deficient. Therefore, this record from Nepal will add new presence data for future status assessment for the species. © 2022 Osterreichische Gesellschaft fur Herpetologie e.V.. All rights reserved
Assessing material densities by vibration analysis and independent component analysis
The aim of this study was to investigate vibration analysis and independent component analysis (ICA) to assess the density of multiple materials making up a single structure. Density is important as it reveals information about physical properties of materials. The density of a single material can be determined from the relationship between its mass and volume. However, when a structure consists of multiple materials, identification of their individual densities from the structure is complicated. Vibration analysis is a technique that reveals information about an object’s physical properties such as its density. The investigation was carried out using a plastic test tube filled separately with three liquids of known densities; water, Chloroform and Methanol. Vibration was inducted into the tube, through an electronic system that produced a single impact at a predefined location on the tube. The resulting vibration signals were recorded using two vibration sensors placed on the tube. A signal source separation technique called ICA was used to obtain the vibration effects of the liquid and the tube. The power spectral densities (PSD) of ICA extracted vibration signals were examined. The frequency of the largest peak in the PSD was related to the liquid’s density under test. The study indicated that vibration analysis may be effective in assessing materials’ densities in a structure that contains multiple materials, however a larger study is needed to explore the findings
First record of Takydromus sikkimensis Günther, 1888 (Squamata, Lacertidae) from Nepal
We report the first record of Sikkim grass lizard, Takydromus sikkimensis Günther, 1888 in Nepal based on morphological characters such as the presence of four pairs of femoral pores, 12 rows of ventral scales, tail more than 3.6 times longer than snout-vent length. Our record of T. sikkimensis at Miklajung, Morang district represents the western-most observation of the species, ca. 94 km west of its type locality, Sikkim, India and is the first in Nepal for this species, genus, and family. This record is from Chure/Siwalik hill range which lies outside of Nepal's protected area network. This species is listed as Endangered by the International Union for Conservation of Nature and Natural Resources and warrants detailed inventory and immediate conservation interventions. © 2022 Osterreichische Gesellschaft fur Herpetologie e.V.. All rights reserved
Determinants Outside the DevR C-Terminal Domain Are Essential for Cooperativity and Robust Activation of Dormancy Genes in Mycobacterium tuberculosis
Background: DevR (also called as DosR) is a two-domain response regulator of the NarL subfamily that controls dormancy adaptation of Mycobacterium tuberculosis (M. tb). In response to inducing signals such as hypoxia and ascorbic acid, the N-terminal receiver domain of DevR (DevRN) is phosphorylated at Asp54. This results in DevR binding to DNA via its C-terminal domain (DevRC) and subsequent induction of the DevR regulon. The mechanism of phosphorylation-mediated activation is not known. The present study was designed to understand the role of the N- and C-terminal domains of DevR in DevR regulon genes activation. Methodology/Principal Findings: Towards deciphering the activation mechanism of DevR, we compared the DNA binding properties of DevRC and DevR and correlated the findings with their ability to activate gene expression. We show that isolated DevRC can interact with DNA, but only with the high affinity site of a representative target promoter. Therefore, one role of DevR N is to mask the intrinsic DNA binding function of DevR C. However, unlike phosphorylated DevR, isolated DevR C does not interact with the adjacent low affinity binding site suggesting that a second role of DevRN is in cooperative binding to the secondary site. Transcriptional analysis shows that consistent with unmasking of its DNA binding property, DevRC supports the aerobic induction, albeit feebly, of DevR regulon genes but is unable to sustain gene activation during hypoxia
Distributional patterns of amphibians and reptiles in Ghandruk, Annapurna Conservation Area, Nepal
In May and October 2017, we assessed the distribution and diversity of herpetofauna in the Ghandruk region of the Annapurna Conservation Area. Using the Visual Encounter Survey (VES) protocol on 11 randomly selected transects, we recorded 662 individuals of 25 herpetofaunal species (12 amphibians and 13 reptiles). Species richness and abundance declined with increases in elevation but only the correlation between elevation and abundance was significant. Neither amphibians nor reptiles were uniformly distributed among different habitats, and species richness of both amphibians and reptiles varied significantly among habitat types. The greatest amphibian species richness was in wetlands, whereas that of reptiles was highest in forests.
 
Study of aerosol optical properties in Lumbini, Nepal
The mixture of different sized particles (fine and coarse) with air composition forms aerosols. Increased economic activities, vehicles, and rapid urbanization made Lumbini one of the heavily polluted regions in Nepal. Data are extracted from AERONET websites between 2013 to 2019 with standard deviation. We are mainly focused on understanding variations in aerosol optical properties: aerosol optical depth (AOD), angstrom parameter (α and β), visibility, single-scattering albedo (SSA), refractive index (real and imaginary), and asymmetry parameter (AP) in the Lumbini region. The maximum value of AOD (675nm) in Lumbini occurred mostly during post-monsoon season (0.61 ± 0.38) whereas, the values of AOD were found to be lower during the monsoon season (0.18 ± 0.12). Most of the AOD values are found to be greater than 0.4, indicating the higher level of pollution in the study area. There is a positive correlation between perceptible water and AOD, maximum correlation (0.4) occurs at the lowest AOD (440nm) while the minimum (0.1) at the highest AOD (1020nm). The turbidity coefficient (β) has an adverse effect on visibility. The Visibility over Lumbini was found to be highest (20 km) during monsoon. Single-scattering albedo (SSA) accretions occur at wavelengths between 440 and 675 nm, but the pattern changes from 675 to 1020 nm. All parameters were found to be distinct and seasonal fluctuations among this station are mainly due to the different aerosols availability such as biomass burning, mixed aerosols, and anthropogenic aerosols over the Lumbini site
Study of aerosol optical properties in Lumbini, Nepal
The mixture of different sized particles (fine and coarse) with air composition forms aerosols. Increased economic activities, vehicles, and rapid urbanization made Lumbini one of the heavily polluted regions in Nepal. Data are extracted from AERONET websites between 2013 to 2019 with standard deviation. We are mainly focused on understanding variations in aerosol optical properties: aerosol optical depth (AOD), angstrom parameter (α and β), visibility, single-scattering albedo (SSA), refractive index (real and imaginary), and asymmetry parameter (AP) in the Lumbini region. The maximum value of AOD (675nm) in Lumbini occurred mostly during post-monsoon season (0.61 ± 0.38) whereas, the values of AOD were found to be lower during the monsoon season (0.18 ± 0.12). Most of the AOD values are found to be greater than 0.4, indicating the higher level of pollution in the study area. There is a positive correlation between perceptible water and AOD, maximum correlation (0.4) occurs at the lowest AOD (440nm) while the minimum (0.1) at the highest AOD (1020nm). The turbidity coefficient (β) has an adverse effect on visibility. The Visibility over Lumbini was found to be highest (20 km) during monsoon. Single-scattering albedo (SSA) accretions occur at wavelengths between 440 and 675 nm, but the pattern changes from 675 to 1020 nm. All parameters were found to be distinct and seasonal fluctuations among this station are mainly due to the different aerosols availability such as biomass burning, mixed aerosols, and anthropogenic aerosols over the Lumbini site
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