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We report on a study on controlled trapping of electrons, by field ionization of nitrogen ions, in laser wakefield accelerators in variable length gas cells. In addition to ionization-induced trapping in the density plateau inside the cells, which results in wide, but stable, electron energy spectra, a regime of ionization-induced trapping localized in the density down-ramp at the exit of the gas

Background: Severe alpha 1-antitrypsin deficiency (PiZZ) predisposes to morbidity and mortality due to early-onset emphysema and liver disease. The risk of death from other causes, including cardiovascular disease and cancer, has not been well investigated. We aimed to analyze cause-specific mortality in PiZZ individuals compared with the general Swedish population. Methods: Data on 1,561 PiZZ ind

In this study, three different kinds of simultaneous saccharification and fermentation (SSF) of washed pretreated corn stover with water-insoluble solids (WIS) content of 20% were investigated to find which one resulted in highest ethanol yield at high-solids loadings. The different methods were batch SSF, prehydrolysis followed by batch SSF and fed-batch SSF. Batch-SSF resulted in an ethanol yiel

The calcitonin receptor (CTR) is relevant to three hormonal systems: amylin, calcitonin, and calcitonin gene-related peptide (CGRP). Receptors for amylin and calcitonin are targets for treating obesity, diabetes, and bone disorders. CGRP receptors represent a target for pain and migraine. Amylin receptors (AMY) are a heterodimer formed by the coexpression of CTR with receptor activity-modifying pr

Most small glaciers in the world have significantly decreased their volume during the last century, which has caused water shortage problems. Glacier No. 1, at the headwaters of the Urumqi River, Tianshan, China, has been monitored since 1959 and similarly has experienced significant mass and volume losses over the last few decades. Thus, we examined the trend and potential abrupt changes of the m

The ignition of nitromethane/O2/N2 mixtures was investigated via shock tube experiments in the temperature range 947–1333 K at reflected shock pressures near 8, 16 and 32 atm. The ignition was recorded as the intensity maxima of unfiltered luminosity in the range 240–530 nm. Under the experimental conditions of the present study, ignition was found to proceed via a two stage process. Dependencies

A new detailed kinetic mechanism for formaldehyde and methanol combustion has been developed using the Konnov mechanism, version 0.6, as a starting point. In total, 82 reactions of the formaldehyde and methanol subsets were reviewed and updated using a systematic approach. Rate constants were selected based on thorough evaluation of available experimental and theoretical data. No modifications of

FTIR smog chamber techniques were used to study the kinetics of the gas-phase reactions of Cl atoms, OD radicals, and O3 with the five-membered ring-structured compounds tetrahydrofuran (C4H8O, THF), 2-methyltetrahydrofuran (CH3C4H7O, 2-MTHF), 2,5-dimethyltetrahydrofuran ((CH3)2C4H5O, 2,5-DMTHF), and furan (C4H4O). The rate coefficients determined using relative rate methods were kTHF+Cl = (1.96 ±

In this article, gas-phase advanced oxidation, a new method for pollution control building on the photo-oxidation and particle formation chemistry occurring in the atmosphere, is introduced and characterized. The process uses ozone and UV-C light to produce in situ radicals to oxidize pollution, generating particles that are removed by a filter; ozone is removed using a MnO2 honeycomb catalyst. Th

The atmospheric chemistry of two C 4H 8O 2 isomers (methyl propionate and ethyl acetate) was investigated. With relative rate techniques in 980 mbar of air at 293 K the following rate constants were determined: k(C 2H 5C(O)OCH 3 + Cl) = (1.57 ± 0.23) × 10 -11, k(C 2H 5C(O) OCH 3 + OH) = (9.25 ± 1.27) × 10 -13, k(CH 3C(O)OC 2H 5 + Cl) = (1.76 ± 0.22) × 10 -11, and k(CH 3C(O)OC 2H 5 + OH) = (1.54 ±

The reaction CHCl3 + Cl → CCl3 + HCl was studied in the atmospherically relevant temperature range from 253 to 313 K and in 930 mbar of N2 diluent using the relative rate method. A temperature dependent reaction rate constant, valid in the temperature range 220-330 K, was determined by a fit to the result of the present study and that of Orlando (1999); k = (3.77 ± 0.32) × 10-12 exp((-1011 ± 24)/T