56 research outputs found
Pion absorption by 3He at the Δ-resonance energy
Pion absorption by 3He was studied at Tπ=165 MeV in a kinematically complete experiment. The cross section for absorption on a (pn) pair of nucleons, σpn(π+), was found to be 17.0±2.6 mb; that for absorption on a (pp) pair, σpp(π-), 0.91±0.20 mb. The angular distribution in the πNN center-of-mass system for σpn(π+) resembles that for the π++d→p+p reaction while the angular distribution for σpp(π-) is strongly backward peaked. Evidence that a significant fraction of the absorptions involves all three target nucleons is seen in the angular correlation between the two detected nucleons as well as in the momentum distribution of the unobserved nucleon. For π+ and π- absorption, the three-body cross sections were found to be 9.6±2.1 and 4.2±01.2 mb, respectively. Neither initial- nor final-state interactions appear to be major contributors to the observed three-body absorption, though initial-state interactions may be contributing to the enhancement of the three-body π+ absorption at the Δ resonance
Nucleoplasmic signals promote directed transmembrane protein import simultaneously via multiple channels of nuclear pores
LINC complexes promote homologous recombination in part through inhibition of nonhomologous end joining
An elevational shift of cryophilous bryophytes in the last century - an effect of climate warming?
Aim To investigate altitudinal range shifts of bryophytes in Switzerland by
comparing recent altitudinal distributions with historical distributions derived
from herbarium specimens.
Location Switzerland, covering 41,285 km2 in Central Europe.
Methods We used a dataset of 8520 herbarium specimens of 61 bryophyte species
and compared altitudinal data between the two periods 1880–1920 and 1980–
2005. The records we used were not specifically sampled for climatological
analyses, but originate from non-systematic fieldwork by various collectors.
Historical and recent records were distributed all over Switzerland with
occurrences in all major biogeographical areas. To account for different
sampling efforts in the two time periods, different subsampling procedures
were applied.
Results Overall, we found a significant mean increase in altitude of 89 ± 29 m
which was mainly driven by the cryophilous species (+222 ± 50 m). The mean
increase in altitude of cryophilous species corresponds to a decadal upward shift
of 24 m. The upper range limit of cryophilous species also increased by
189 ± 55 m, but there was no effect on the lower range limit. For intermediate
and thermophilous species neither mean, nor upper or lower range limits
changed. However, the proportion of records of thermophilous to cryophilous
species increased considerably at lower altitudes, but levelled off above
approximately 1800 m.
Main conclusions We conclude that cryophilous bryophytes are expanding their
range to higher elevations in Switzerland and that at lower elevations, a slow
extinction process is going on, probably as a result of climate warming trends. The
observed decadal upward shifts of cryophilous species closely match those
reported from vascular plants in Europe and those expected, given recent
estimates of climate warming trends. We emphasize that herbaria provide
valuable data that can be used to detect ongoing changes in the distribution of
species
A COMPARISON OF VARIOUS DISCRETIZATION SCHEMES FOR THE STATIONARY SEMICONDUCTOR DEVICE CONTINUITY EQUATION
Sleep Position Detection for Closed-Loop Treatment of Sleep-Related Breathing Disorders
Reliable detection of sleep positions is essential for the development of technical aids for patients with position-dependent sleep-related breathing disorders. We compare personalized and generalizable sleeping position classifiers using unobtrusive eight-channel pressure-sensing mats. Data of six male patients with confirmed position-dependent sleep apnea was recorded during three subsequent nights. Personalized position classifiers trained using leave-one-night-out cross-validation on average reached an F1-score of 61.3% for supine/non-supine and an F1-score of 46.2% for supine/lateral-left/lateral-right classification. The generalizable classifiers reached average F1-scores of 62.1% and 49.1% for supine/non-supine and supine/lateral-left/lateral-right classification, respectively. In-bed presence ('bed occupancy') could be detected with an average F1-score of 98.1%. This work shows that personalized sleep-position classifiers trained with data from two nights have comparable performance to classifiers trained with large interpatient datasets. Simple eight-channel sensor mattresses can be used to accurately detect in-bed presence required for closed-loop systems but their use to classify sleep-positions is limited
Sleep Position Detection for Closed-Loop Treatment of Sleep-Related Breathing Disorders
Reliable detection of sleep positions is essential for the development of technical aids for patients with position-dependent sleep-related breathing disorders. We compare personalized and generalizable sleeping position classifiers using unobtrusive eight-channel pressure-sensing mats. Data of six male patients with confirmed position-dependent sleep apnea was recorded during three subsequent nights. Personalized position classifiers trained using leave-one-night-out cross-validation on average reached an F1-score of 61.3% for supine/non-supine and an F1-score of 46.2% for supine/lateral-left/lateral-right classification. The generalizable classifiers reached average F1-scores of 62.1% and 49.1% for supine/non-supine and supine/lateral-left/lateral-right classification, respectively. In-bed presence ("bed occupancy") could be detected with an average F1-score of 98.1%. This work shows that personalized sleep-position classifiers trained with data from two nights have comparable performance to classifiers trained with large interpatient datasets. Simple eight-channel sensor mattresses can be used to accurately detect in-bed presence required for closed-loop systems but their use to classify sleep-positions is limited
Profiles of the Essential Oils and Headspace Analysis of Volatiles from Mandragora autumnalis Bertol. Growing Wild in Tunisia
Mandragora autumnalis Bertol. (Solanaceae family), synonym of M. officinalis Mill., occurs in North Africa and grows natively in Northern and Central Tunisia, in humid to sub-arid climates. The ripe fruits of mandrake are odiferous with a particular, indescribable, specific odor, shared, to a lesser extent, by the leaves and roots. We carried out an investigation of the essential oils (EOs) and of the aromatic volatiles emitted by fresh leaves, roots and ripe fruits of M. autumnalis growing wild in Central Tunisia. The EOs were obtained from freshly collected plant material by hydrodistillation, while the volatile emissions from the powdered M. autumnalis tissues were sampled by headspace solid phase microextraction (HS-SPME); both types of samples were analyzed by gas chromatography-mass spectrometry (GC/MS). Fifty-one compounds representing 96.2-98.6% of the total oil compositions were identified in the three tissues and belonged to different chemical classes specifically in 16 esters, 12 alcohols, 12 hydrocarbons, 6 ketones, 3 aldehydes and 3 acids. The main constituents were pentadecanoic acid (34.2%) and n-hexadecanol (26.3%). A total of 78 volatile compounds emanating from M. autumnalis tissues, representing 94.1-96.4% of the total volatile compositions, were identified: 22 esters, 11 alcohols, 9 aldehydes, 14 ketones, 7 nitrogen,10 hydrocarbons, 2 lactones, 1 sulfur, and 2 ethers. n-Ethyl hexanoate (12.3%) and 1,3-butanediol (12.3%) were at the highest relative percentages. This study characterizes and distinguishes M. autumnalis from Tunisia and attributes the compounds responsible for the intoxicating and particular odour of fruits
Profiles of the Essential Oils and Headspace Analysis of Volatiles from Mandragora autumnalis
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