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Estimating the environmental and economic impacts of widespread adoption of potential technology solutions to reduce water use and pollution: Application to China's textile industry
Comparison of Energy Budget of Cockroach Nymph (Hemimetabolous) and Hornworm (Holometabolous) under Food Restriction
Animals with different life histories budget their intake energy differently when food availability is low. It has been shown previously that hornworm (larva of Manduca sexta), a holometabolous insect species with a short development stage, prioritizes growth at the price of metabolism under food restriction, but it is unclear how hemimetabolous insect species with a relatively long development period budget their intake energy under food scarcity. Here, we use orange head cockroaches (Eublaberus posticus) to investigate this question. We found that for both species under food restriction, rates of metabolism and growth were suppressed, but the degree of reduction was more severe in growth than that of metabolism for cockroaches. Under both free-feeding and food restriction conditions, hornworms allocated a larger fraction of assimilated energy to growth than to metabolism, and cockroaches were the opposite. More importantly, when food availability was low, the fraction of assimilated energy allocated to growth was reduced by 120% in cockroaches, and the energy from growth was channeled to compensate for the reduction in metabolism; but, the fraction of assimilated energy allocated to growth was only reduced by 14% in hornworms. These results suggest that, compared to hornworms, cockroaches prioritize metabolism over growth
Transport in Molecular Junctions with Different Metallic Contacts
Ab initio calculations of phenyl dithiol connected to Au, Ag, Pd, and Pt
electrodes are performed using non-equilibrium Green's functions and density
functional theory. For each metal, the properties of the molecular junction are
considered both in equilibrium and under bias. In particular, we consider in
detail charge transfer, changes in the electrostatic potential, and their
subsequent effects on the IV curves through the junctions. Gold is typically
used in molecular junctions because it forms strong chemical bonds with sulfur.
We find however that Pt and Pd make better electrical contacts than Au. The
zero-bias conductance is found to be greatest for Pt, followed by Pd, Au, and
then Ag
Determinants of Farm Households' Willingness to Accept (WTA) Compensation for Conservation Technologies: Ethiopia, Amhara Region, Northern Showa
The purpose of this study was to investigate and evaluate the WTP limits of irrigation water in the Sheva region of the Northern Amhara region of Ethiopia to understand whether irrigation water is feasible. Data were collected from primary research sources. An upright bivariate model was used to determine households' willingness to address irrigation water problems in the study area. Using data from a sample of 800 farmers, the results show that WTP is positive for irrigation water in the North Sheva region. The results show that the average household can obtain irrigation water for about 3,001.47 0.25 hectares of land in Ethiopia, which is a one-time irrigation land value of US$100.05 at the current exchange rate. In addition, the study found that household size, agricultural experience, household costs, irrigated land, livestock capital education level, and measured tropical livestock live-stock units had a positive effect on willingness to pay for irrigation water. Capital is adversely affected by family age, but market access for farmers is not guaranteed. Based on the pursuit, convincing reliability constraints, increasing market access through information and irrigation schemes, and increasing farmers' awareness of irrigation water and its use, is the efficient use of irrigation and irrigation water. Valid maintenance conditions are recommended. Stick to discipline
Assessing the Influence of Indoor Exposure to “Outdoor Ozone” on the Relationship between Ozone and Short-term Mortality in U.S. Communities
Background: City-to-city differences have been reported for the increase in short-term mortality associated with a given increase in ozone concentration (ozone mortality coefficient). Although ozone concentrations are monitored at central outdoor locations, a large fraction of total ozone exposure occurs indoors
Discovery of a New Member of the Inner Oort Cloud from The Next Generation Virgo Cluster Survey
We report the discovery of 2010 GB, a likely new member of the Inner
Oort Cloud (IOC). 2010 GB is one of 91 Trans Neptunian Objects (TNOs)
and Centaurs discovered in a 76 deg contiguous region imaged as part of the
Next Generation Virgo Cluster Survey (NGVS) --- a moderate ecliptic latitude
survey reaching a mean limiting magnitude of --- using
MegaPrime on the 3.6m Canada France Hawaii Telescope. 2010 GB is found
to have an orbit with semi-major axis AU, inclination and pericentre AU. This is the second largest
perihelion distance among known solar system objects. Based on the sky coverage
and depth of the NGVS, we estimate the number of IOC members with sizes larger
than 300 km ( mag) to be . A comparison of the
detection rate from the NGVS and the PDSSS (a characterized survey that
`re-discovered' the IOC object Sedna) gives, for an assumed a power-law LF for
IOC objects, a slope of , with only two detections
in this region this slope estimate is highly uncertain.Comment: 20 pages, 3 figures, 1 table. Accepted for publication in The
Astrophysical Journal Letter
Simulation of nonlinear superconducting rf losses derived from characteristic topography of etched and electropolished niobium surfaces
A simplified numerical model has been developed to simulate nonlinear superconducting radiofrequency (SRF) losses on Nb surfaces. This study focuses exclusively on excessive surface resistance (R-s) losses due to the microscopic topographical magnetic field enhancements. When the enhanced local surface magnetic field exceeds the superconducting critical transition magnetic field H-c, small volumes of surface material may become normal conducting and increase the effective surface resistance without inducing a quench. We seek to build an improved quantitative characterization of this qualitative model. Using topographic data from typical buffered chemical polish (BCP)- and electropolish (EP)-treated fine grain niobium, we have estimated the resulting field-dependent losses and extrapolated this model to the implications for cavity performance. The model predictions correspond well to the characteristic BCP versus EP high field Q(0) performance differences for fine grain niobium. We describe the algorithm of the model, its limitations, and the effects of this nonlinear loss contribution on SRF cavity performance
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