Regional assessment of groundwater vulnerability in the Snake river plain aquifer basin, USA

El sistema acuífero del río Snake en Idaho oriental es una de los más grandes e importantes fuentes regionales de agua en los Estados Unidos. Salvaguardar este sistema acuífero de la contaminación por el Laboratorio Nacional Ambiental y de Ingeniería de Idaho (INEEL) es de crítica importancia para el Depto. de Energía Norteamericano. Este trabajo contiene el resultado de las siguientes investigaciones: analizar el impacto de factores naturales sobre la vulnerabilidad de las aguas subterráneas; desarrollar el mapa de vulnerabilidad acuífera a la contaminación, indicar sitios contaminados de riesgo de contaminación acuífera usando el mapa. Se puso especial atención a la zona vadosa (zona de aeración) que determina el peligro potencial de penetración de un contaminante desde la superficie al agua subterránea. La evaluación del papel de la protección a la zona vadosa fue basada en los siguientes factores de control: factores pasivos - profundidad al agua y propiedades conductoras del medio insaturado; factores activos - recarga incluyendo sus partes principales: precipitación e irrigación. La evaluación de la vulnerabilidad fue hecha paso a paso para compilar una serie de mapas. Combinando el mapa de la zona vadosa y el de recarga al oriente de la planicie del río Snake, el mapa resultante refleja todos los factores antes mencionados. El sistema Point Count constituyó un concepto principal de evaluación de vulnerabilidad. La influencia de cada factor fue especificado por diferentes números (rangos), los cuales fueron determinados por expertos. A menor el rango, más favorables la situación en relación con la vulnerabilidad del agua subterránea. La vulnerabilidad acuífera es caracterizada por la suma de rangos que puede variar de 8 a 40 en la región estudiada. La suma total de rangos caracteriza la vulnerabilidad acuífera a la contaminación

Recent regional warming across the Siberian lowlands: a comparison between permafrost and non-permafrost areas

The northern mid-high latitudes experience climate warming much faster than the global average. However, the difference in the temperature change rates between permafrost and non-permafrost zones remains unclear. In this study, we investigated the temporal changes in temperature means and extremes across the Siberian lowlands (<500 m) over the past six decades (1960–2019) using in situ observations and reanalysis data. The results show that permafrost zones (0.39 °C/decade) have warmed faster than non-permafrost zones (0.31 °C/decade). The minimum values of the daily maximum ( TXn ) and minimum ( TNn ) temperatures changed faster than their maximum values ( TXx, TNx ), suggesting that low minimum temperatures increase faster, as evidenced by the considerably higher warming rate in the cool season (October–April, 0.43 ± 0.10 °C/decade, n = 126) than that in the warm season (May–September, 0.25 ± 0.08 °C/decade, n = 119). The change rates of TXx and TNx in permafrost areas were 2–3 times greater than those in non-permafrost areas; however, over the last ten years, TXx and TNx in non-permafrost areas showed decreasing trends. Moreover, faster-warming permafrost regions do not exhibit a faster increase in surface net solar radiation than slower-warming non-permafrost regions. While our findings suggest that carbon emissions from thawing soils are likely a potential driver of rapid warming in permafrost-dominated regions, the potential feedback between ground thawing and climate warming in permafrost regions remains uncertain

A database of water chemistry in eastern Siberian rivers

Measurement(s) water chemistry Technology Type(s) chromatography and spectrometry Sample Characteristic - Environment hydrochemistry Sample Characteristic - Location Eastern Siberi

Direct observation of the dead-cone effect in quantum chromodynamics

The direct measurement of the QCD dead cone in charm quark fragmentation is reported, using iterative declustering of jets tagged with a fully reconstructed charmed hadron

Production of light-flavor hadrons in pp collisions at √s = 7 and √s = 13 TeV

The production of π±, K±, K0S, K∗(892)0, p, ϕ(1020), Λ, Ξ−, Ω−, and their antiparticles was measured in inelastic proton–proton (pp) collisions at a center-of-mass energy of s√ = 13 TeV at midrapidity (|y|<0.5) as a function of transverse momentum (pT) using the ALICE detector at the CERN LHC. Furthermore, the single-particle pT distributions of K0 S, , and in inelastic pp collisions at √s = 7 TeV are reported here for the first time. The pT distributions are studied at midrapidity within the transverse momentum range 0 ≤ pT ≤ 20 GeV/c, depending on the particle species. The pT spectra, integrated yields, and particle yield ratios are discussed as a function of collision energy and compared with measurements at lower √s and with results from various general-purpose QCD-inspired Monte Carlo models. A hardening of the spectra at high pT with increasing collision energy is observed, which is similar for all particle species under study. The transverse mass and xT ≡ 2pT/ √s scaling properties of hadron production are also studied. As the collision energy increases from √s = 7–13 TeV, the yields of non- and single-strange hadrons normalized to the pion yields remain approximately constant as a function of √s, while ratios for multi-strange hadrons indicate enhancements. The pT-differential cross sections of π±, K± and p (p) are compared with next-to-leading order perturbative QCD calculations, which are found to overestimate the cross sections for π± and p (p) at high pT

Measurement of beauty and charm production in pp collisions at √s = 5.02 TeV via non-prompt and prompt D mesons

The pT-differential production cross sections of prompt and non-prompt (produced in beauty-hadron decays) D mesons were measured by the ALICE experiment at midrapidity (|y| < 0.5) in proton-proton collisions at s√s = 5.02 TeV. The data sample used in the analysis corresponds to an integrated luminosity of (19.3 ± 0.4) nb−1. D mesons were reconstructed from their decays D0 → K−π+, D+ → K−π+π+, and D+s→φπ+→K−K+π+Ds+→φπ+→K−K+π+ and their charge conjugates. Compared to previous measurements in the same rapidity region, the cross sections of prompt D+ and D+sDs+ mesons have an extended pT coverage and total uncertainties reduced by a factor ranging from 1.05 to 1.6, depending on pT, allowing for a more precise determination of their pT-integrated cross sections. The results are well described by perturbative QCD calculations. The fragmentation fraction of heavy quarks to strange mesons divided by the one to non-strange mesons, fs/(fu + fd), is compatible for charm and beauty quarks and with previous measurements at different centre-of-mass energies and collision systems. The bb¯¯¯bb¯ production cross section per rapidity unit at midrapidity, estimated from non-prompt D-meson measurements, is dσbb¯¯¯/dy∣∣|y|<0.5=34.5±2.4(stat)+4.7−2.9(tot.syst)dσbb¯/dy||y|<0.5=34.5±2.4(stat)−2.9+4.7(tot.syst) μb. It is compatible with previous measurements at the same centre-of-mass energy and with the cross section pre- dicted by perturbative QCD calculations