3,803 research outputs found
Coherent states for polynomial su(1,1) algebra and a conditionally solvable system
In a previous paper [{\it J. Phys. A: Math. Theor.} {\bf 40} (2007) 11105],
we constructed a class of coherent states for a polynomially deformed
algebra. In this paper, we first prepare the discrete representations of the
nonlinearly deformed algebra. Then we extend the previous procedure
to construct a discrete class of coherent states for a polynomial su(1,1)
algebra which contains the Barut-Girardello set and the Perelomov set of the
SU(1,1) coherent states as special cases. We also construct coherent states for
the cubic algebra related to the conditionally solvable radial oscillator
problem.Comment: 2 figure
Association of different restriction levels with COVID-19-related distress and mental health in somatic inpatients: a secondary analysis of swiss general hospital data
Background: The coronavirus disease 2019 (COVID-19) pandemic and related countermeasures hinder health care access and affect mental wellbeing of non-COVID-19 patients. There is lack of evidence on distress and mental health of patients hospitalized due to other reasons than COVID-19-a vulnerable population group in two ways: First, given their risk for physical diseases, they are at increased risk for severe courses and death related to COVID-19. Second, they may struggle particularly with COVID-19 restrictions due to their dependence on social support. Therefore, we investigated the association of intensity of COVID-19 restrictions with levels of COVID-19-related distress, mental health (depression, anxiety, somatic symptom disorder, and mental quality of life), and perceived social support among Swiss general hospital non-COVID-19 inpatients. Methods: We analyzed distress of 873 hospital inpatients not admitted for COVID-19, recruited from internal medicine, gynecology, rheumatology, rehabilitation, acute geriatrics, and geriatric rehabilitation wards of three hospitals. We assessed distress due to the COVID-19 pandemic, and four indicators of mental health: depressive and anxiety symptom severity, psychological distress associated with somatic symptoms, and the mental component of health-related quality of life; additionally, we assessed social support. The data collection period was divided into modest (June 9 to October 18, 2020) and strong (October 19, 2020, to April 17, 2021) COVID-19 restrictions, based on the Oxford Stringency Index for Switzerland. Results: An additional 13% (95%-Confidence Interval 4-21%) and 9% (1-16%) of hospital inpatients reported distress related to leisure time and loneliness, respectively, during strong COVID-19 restrictions compared to times of modest restrictions. There was no evidence for changes in mental health or social support. Conclusions: Focusing on the vulnerable population of general hospital inpatients not admitted for COVID-19, our results suggest that tightening of COVID-19 restrictions in October 2020 was associated with increased COVID-19-related distress regarding leisure time and loneliness, with no evidence for a related decrease in mental health. If this association was causal, safe measures to increase social interaction (e.g., virtual encounters and outdoor activities) are highly warranted. Trial registration: www.ClinicalTrials.gov, identifier: NCT04269005
Children\u27s Understanding of the Concept of Physical Activity
This study evaluated 4th-grade students\u27 understanding of the concept of physical activity and assessed the effects of two interventions to enhance the students\u27 understanding of this concept. Students were randomly assigned to 1 of 3 conditions: the video group (n=40) watched a 5-min video describing physical activity; the verbal group (n=42) listened to a generic description of physical activity; the control group received no instruction (n=45). Students completed a 17-item checklist testing their understanding of the concept of physical activity. Compared to controls, students in the verbal and video group demonstrated significantly higher checklist scores, with the video group scoring significantly higher than the verbal group. Only 35.6% of the controls compared to 52.4% and 70.0% of the verbal and video group respectively, could classify \u3e 15 of the checklist items correctly. The results indicate that, without intervention, children have a limited understanding of the concept of physical activity
Tracking of Physical Activity, Physical Inactivity, and Health-Related Physical Fitness in Rural Youth
This study examined the tracking of selected measures of physical activity, inactivity, and fitness in a cohort of rural youth. Students (N=181, 54.7% female, 63.5% African American) completed test batteries during their fifth- (age=10.7±0.7 years), sixth-, and seventh-grade years. The Previous Day Physical Activity Recall (PDPAR) was used to assess 30-min blocks of vigorous physical activity (VPA), moderate-to-vigorous physical activity (MVPA), TV watching and other sedentary activities, and estimated energy expenditure (EE). Fitness measures included the PWC 170 cycle ergometer test, strength tests, triceps skinfold thickness, and BMI. Intraclass correlation coefficients (ICCs) for VPA, MVPA, and after-school EE ranged from 0.63 to 0.78. ICCs ranged from 0.49 to 0.71 for measures of inactivity and from 0.78 to 0.82 for the fitness measures. These results indicate that measures of physical activity, inactivity, and physical fitness tend to track during the transition from elementary to middle school
Spectroscopy of QUBRICS quasar candidates: 1672 new redshifts and a golden sample for the Sandage test of the redshift drift
The QUBRICS (QUasars as BRIght beacons for Cosmology in the Southern hemisphere) survey aims at constructing a sample of the brightest quasars with z∼> 2.5, observable with facilities in the Southern Hemisphere. QUBRICS makes use of the available optical and IR wide-field surveys in the South and of Machine Learning techniques to produce thousands of bright quasar candidates of which only a few hundred have been confirmed with follow-up spectroscopy. Taking advantage of the recent Gaia Data Release 3, which contains 220 million low-resolution spectra, and of a newly developed spectral energy distribution fitting technique, designed to combine the photometric information with the Gaia spectroscopy, it has been possible to measure 1672 new secure redshifts of QUBRICS candidates, with a typical uncertainty of σz = 0.02. This significant progress of QUBRICS brings it closer to (one of) its primary goals: providing a sample of bright quasars at redshift 2.5 < z < 5 to perform the Sandage test of the cosmological redshift drift. A Golden Sample of seven quasars is presented that makes it possible to carry out this experiment in about 1500 h of observation in 25 yr, using the ANDES spectrograph at the 39m ELT, a significant improvement with respect to previous estimates
Vector coherent states and intertwining operators
In this paper we discuss a general strategy to construct vector coherent
states of the Gazeau-Klauder type and we use them to built up examples of
isospectral hamiltonians. For that we use a general strategy recently proposed
by the author and which extends well known facts on intertwining operators. We
also discuss the possibility of constructing non-isospectral hamiltonians with
related eigenstates
Target specificity among canonical nuclear poly(A) polymerases in plants modulates organ growth and pathogen response
Polyadenylation of pre-mRNAs is critical for efficient nuclear export, stability, and translation of the mature mRNAs, and thus for gene expression. The bulk of pre-mRNAs are processed by canonical nuclear poly(A) polymerase (PAPS). Both vertebrate and higher-plant genomes encode more than one isoform of this enzyme, and these are coexpressed in different tissues. However, in neither case is it known whether the isoforms fulfill different functions or polyadenylate distinct subsets of pre-mRNAs. Here we show that the three canonical nuclear PAPS isoforms in Arabidopsis are functionally specialized owing to their evolutionarily divergent C-terminal domains. A strong loss-of-function mutation in PAPS1 causes a male gametophytic defect, whereas a weak allele leads to reduced leaf growth that results in part from a constitutive pathogen response. By contrast, plants lacking both PAPS2 and PAPS4 function are viable with wild-type leaf growth. Polyadenylation of SMALL AUXIN UP RNA (SAUR) mRNAs depends specifically on PAPS1 function. The resulting reduction in SAUR activity in paps1 mutants contributes to their reduced leaf growth, providing a causal link between polyadenylation of specific pre-mRNAs by a particular PAPS isoform and plant growth. This suggests the existence of an additional layer of regulation in plant and possibly vertebrate gene expression, whereby the relative activities of canonical nuclear PAPS isoforms control de novo synthesized poly(A) tail length and hence expression of specific subsets of mRNAs
Alpha scattering and capture reactions in the A = 7 system at low energies
Differential cross sections for He- scattering were measured in
the energy range up to 3 MeV. These data together with other available
experimental results for He and H scattering were
analyzed in the framework of the optical model using double-folded potentials.
The optical potentials obtained were used to calculate the astrophysical
S-factors of the capture reactions HeBe and
HLi, and the branching ratios for the transitions into
the two final Be and Li bound states, respectively. For
HeBe excellent agreement between calculated and
experimental data is obtained. For HLi a value
has been found which is a factor of about 1.5 larger than the adopted value.
For both capture reactions a similar branching ratio of has been obtained.Comment: submitted to Phys.Rev.C, 34 pages, figures available from one of the
authors, LaTeX with RevTeX, IK-TUW-Preprint 930540
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