Diversity of butterflies with respect to altitudinal rise at various pockets of the Langtang National Park, central Nepal

The Langtang National Park which covers an area of 1760 sq.km was studied extensively for the occurrence and status of butterflies within the altitudinal ranges of 1500 m at Syaprubensi to 4300 m around Langtang glacier area. Addition to altitudes, the decline in floral diversity with temperature reduction in higher elevation basically controlled the species richness of butterflies specifically above 3000 m elevations. Habitat preference for diverse species of these colorful and agile insects is poorly represented above that elevation. This study conducted at different periods in 2010 and 2011 covering both the spring and summer seasons came up with a list of different status categories of 126 species. A rich diversity was noted at 1500 m (Syaprubensi) to 2900 m at Deurali on the way to the glacier (4300 m). Parnassius hardwickei and Parnassius epaphus epaphus which were seen with good population in previous studies at Dhimsa (3200 m) are at declining stage as a consequence of habitat loss and human interferences

Vegetation types and wildlife occurrence in Baghmara Buffer zone community forest

Baghmara Buffer Zone Community Forest (BBZCF) is located in the central lowland of Nepal by covering 215 ha area. A year round study was conducted on 2010 in the area to find out the vegetation types and associated large wild mammals in that vegetation. To collect the primary data on vegetation 34 parallel transects traversing east to west were established. The transect pass through the all habitat types of BBZCF. Total length of transects were 68 kilometers. Nested quadrates (n = 131) were laid in each transects to collect information about vegetation type and wildlife occurrence. Vegetation types of the area were classified on the basis of Importance Value (IV) of tree species for forest area and Prominance Value (PV) of herbs and grass species in grassland area. Six vegetation types namely Acacia catechu forest, Albizia julibrissin forest, Savana, Dalbergia sissoo forest, Trewia nudiflora forest, and Grassland were reported from the study area. Wildlife signs were found only from naturally regenerated forests areas of BBZCF. On the basis of the availability of indirect signs it was found that wildlife were distributed in Albizia julibrissin forest, Trewia nudiflora forest, and grasslands of the study area. From those vegetation types, Spotted deer, Sambhar, Wild boar, Barking deer, and Rhinos were recorded. Among the studied wildlife, Spotted deer and Sambhar preferred Trewia nudiflora forest and rest of the wildlife preferred Albizia julibrissin forest as their habitats

Usage of statistical modeling of lightning leader advancement process in the last stroke phase for determination of lightning protection system parameters

In the paper, the experimental data on the electrical physical characteristics of long spark gaps and lightning are used to create a lightning leader development model in the last stroke phase. The model is verified by comparison of the calculated probabilities of lightning attachments to air terminals and protected objects with normalized level. In order to determine the influence of ground system resistance on protection ability for lightning air terminals, lightning attachments with different ground system resistances have been modeled. The proposed method has been implemented for the calculation of lightning strokes probability to objects of an extended facility with oil storage tanks

Broad-band X-ray observation of broad-line radio galaxy 3C 109

We present a study of the central engine in the broad-line radio galaxy 3C 109. To investigate the immediate surrounding of this accreting, supermassive black hole, we perform a multi-epoch broad-band spectral analysis of a joint NuSTAR/XMM observation (2017), an archival xmm observation (2005) and the 105-month averaged Swift-BAT data. We are able to clearly separate the spectrum into a primary continuum, neutral and ionized absorption, and a reflection component. The photon index of the primary continuum has changed since 2005 ($\Gamma = 1.61 \substack{+0.02 \\ -0.01} \rightarrow 1.54 \pm{0.02}$), while other components remain unchanged, indicative of minimal geometric changes to the central engine. We constrain the high-energy cutoff of 3C 109 (E$_{\text{cut}}= 49 \substack{+7 \\ -5}$\,keV ) for the first time. The reflector is found to be ionized (log $\xi$ = $2.3 \substack{+0.1 \\ -0.2}$) but no relativistic blurring is required by the data. SED analysis confirms the super-Eddington nature of 3C 109 initially ($\lambda_{Edd} >$ 2.09). However, we do not find any evidence for strong reflection (R = $0.18 \substack{+0.04 \\ -0.03}$) or a steep power law index, as expected from a super-Eddington source. This puts the existing virial mass estimate of 2 $\times 10^{8}$M$_{\odot}$ into question. We explore additional ways of estimating the Eddington ratio, some of which we find to be inconsistent with our initial SED estimate. We obtain a new black hole mass estimate of 9.3 $\times 10^{8}$M$_{\odot}$, which brings all Eddington ratio estimates into agreement and does not require 3C 109 to be super-Eddington.Comment: 13 pages, 8 figure

A reference relative time-scale as an alternative to chronological age for cohorts with long follow-up

Background: Epidemiologists have debated the appropriate time-scale for cohort survival studies; chronological age or time-on-study being two such time-scales. Importantly, assessment of risk factors may depend on the choice of time-scale. Recently, chronological or attained age has gained support but a case can be made for a ‘reference relative time-scale’ as an alternative which circumvents difficulties that arise with this and other scales. The reference relative time of an individual participant is the integral of a reference population hazard function between time of entry and time of exit of the individual. The objective here is to describe the reference relative time-scale, illustrate its use, make comparison with attained age by simulation and explain its relationship to modern and traditional epidemiologic methods. Results: A comparison was made between two models; a stratified Cox model with age as the time-scale versus an un-stratified Cox model using the reference relative time-scale. The illustrative comparison used a UK cohort of cotton workers, with differing ages at entry to the study, with accrual over a time period and with long follow-up. Additionally, exponential and Weibull models were fitted since the reference relative time-scale analysis need not be restricted to the Cox model. A simulation study showed that analysis using the reference relative time-scale and analysis using chronological age had very similar power to detect a significant risk factor and both were equally unbiased. Further, the analysis using the reference relative time-scale supported fully-parametric survival modelling and allowed percentile predictions and mortality curves to be constructed. Conclusions: The reference relative time-scale was a viable alternative to chronological age, led to simplification of the modelling process and possessed the defined features of a good time-scale as defined in reliability theory. The reference relative time-scale has several interpretations and provides a unifying concept that links contemporary approaches in survival and reliability analysis to the traditional epidemiologic methods of Poisson regression and standardised mortality ratios. The community of practitioners has not previously made this connection

Impact of air pollution on global burden of disease in 2019

Air pollution consisting of ambient air pollution and household air pollution (HAP) threatens health globally. Air pollution aggravates the health of vulnerable people such as infants, children, women, and the elderly as well as people with chronic diseases such as cardiorespiratory illnesses, little social support, and poor access to medical services. This study is aimed to estimate the impact of air pollution on global burden of disease (GBD). We extracted data about mortality and disability adjusted life years (DALYs) attributable to air pollution from 1990 to 2019. The extracted data were then organized and edited into a usable format using STATA version 15. Furthermore, we also estimated the impacts for three categories based on their socio-demographic index (SDI) as calculated by GBD study. The impacts of air pollution on overall burden of disease by SDI, gender, type of pollution, and type of disease is estimated and their trends over the period of 1990 to 2019 are presented. The attributable burden of ambient air pollution is increasing over the years while attributable burden of HAP is declining over the years, globally. The findings of this study will be useful for evidence-based planning for prevention and control of air pollution and reduction of burden of disease from air pollution at global, regional, and national levels

Network-coding-based Cooperative V2V Communication in Vehicular Cloud Networks

Chinacom 2018 - 13th EAI International Conference on Communications and Networking in China, 23-25 October 2018, Chengdu, ChinaThis is the author accepted manuscript. the final version is available from Springer Verlag via the DOI in this recordWe investigate the potential of applying cooperative relaying and network coding techniques to support vehicle-to-vehicle (V2V) communication in vehicular cloud networks (VCN). A reuse-mode MIMO content distribution system with multiple sources, multiple relays, and multiple destinations under Nakagami-m fading is considered. We apply a class of finite field network codes in the relays to achieve high spatial diversity in an efficient manner and derive the system communication error probability that the destinations fail to recover the desired source messages. The results show that our method can improve the performance over conventional data transmission solutions

Chromium coated silicon nitride electron beam exit window

A Si3N4 membrane with a thin Cr coating is proposed and demonstrated as an electron beam exit window. On average, 85% electron power transmission efficiency was achieved with a 1 μm thick Si3N4 membrane coated with 1 μm thick Cr and the membrane sustained a beam current of up to 3 mA at 60 keV electron energy for the continuous operation of 3 min. However, for an uncoated membrane of same thickness, the average electron power transmission efficiency was 71% and the maximum beam current sustained was 800 μA. It was also shown that a one micron thick Si3N4 square membrane window of 10 mm × 10 mm could withstand a differential pressure of 1.3 bars.The work carried out at Brunel University was co-funded by the EC Seventh Framework Programme theme FP7-SST-2011-RTD-1 for the DEECON project (grant number 284745)

Lethality mechanisms in Escherichia coli induced by intense sub-microsecond electrical pulses

In this letter, the authors present the inactivation kinetics of cells of Escherichia coli and its mutants following treatment with high-intensity electrical pulses of 700 and 32 ns durations. Their experimental results suggest that bacterial inactivation by 700 ns pulses is consistent with a mechanism of reversible electroporation, whereas inactivation by 32 ns pulses may occur as a result of damage to intracellular components. They believe that their results represent a first step towards elucidating the mechanism of lethality of submicrosecond pulses of different durations in prokaryotes