Determination of molecular spectroscopic parameters and energy-transfer rates by double-resonance spectroscopy

The spectroscopy of small to medium-size polyatomic molecules can be extremely complex, especially in higher-lying overtone and combination vibrational levels. The high density of levels also complicates the understanding of inelastic collision processes, which is required to model energy transfer and collision broadening of spectral lines. Both of these problems can be addressed by double-resonance spectroscopy, i.e., time-resolved pump-probe measurements using microwave, infrared, near-infrared, and visible-wavelength sources. Information on excited-state spectroscopy, transition moments, inelastic energy transfer rates and propensity rules, and pressure-broadening parameters may be obtained from such experiments. Examples are given for several species of importance in planetary atmospheres, including ozone, silane, ethane, and ammonia

A Test-Case on Continuation Methods for Bladed-Disk Vibration with Contact and Friction

Bladed-disks in turbo-machines experience harsh operating conditions and undergo high vibration amplitudes if not properly damped. Friction at the blade-to-blade or blade-to-disk interfaces plays a key role in dampening the high amplitudes. Due to the inherent complexity of these structures and non-linearities introduced by the friction joints, accurate response prediction becomes very difficult. There are variety of methods in the literature to predict non-linear vibration due to contact friction. However, their application to the bladed-disks remains limited. Furthermore, there are not many 3D realistic test-cases in the open literature for testing those methods and serve as a benchmark. A bladed-disk representative of a real turbine is presented as an open numerical test-case for the research community. It is characterized by a blade root joint and a shroud joint. The bladed-disk sector is meshed in different ways along with component mode synthesis (CMS) model order reduction for onward non-linear computations. The steady-state solution is obtained by multi-Harmonic Balance method and then continuation method is employed to predict the non-linear frequency response. Thus, it can serve as a case for testing previous and new methods as well as a benchmark for comparative studies

Infrared absorption measurement and analysis of HgTe–CdTe superlattices

The near-band-gap optical properties of superlattice are essential in determining the usefulness of these structures for application in infrared systems. In this paper we report on studies of a HgTe–CdTe superlattice. The optical characterization of the superlattice in the infrared was carried out by measuring its photoluminescence, transmission, and photoconductivity spectra. Results of these measurements as functions of temperature are presented, as are the theoretically calculated absorption spectra. We obtained good agreement between different measurement techniques and the theoretical model for the optical absorption and band gap

The effect of radiation dose on mouse skeletal muscle remodeling

BackgroundThe purpose of this study was to determine the effect of two clinically relevant radiation doses on the susceptibility of mouse skeletal muscle to remodeling.Materials and methods.Alterations in muscle morphology and regulatory signaling were examined in tibialis anterior and gastrocnemius muscles after radiation doses that differed in total biological effective dose (BED). Female C57BL/6 (8-wk) mice were randomly assigned to non-irradiated control, four fractionated doses of 4 Gy (4x4 Gy; BED 37 Gy), or a single 16 Gy dose (16 Gy; BED 100 Gy). Mice were sacrificed 2 weeks after the initial radiation exposure.ResultsThe 16 Gy, but not 4x4 Gy, decreased total muscle protein and RNA content. Related to muscle regeneration, both 16 Gy and 4x4 Gy increased the incidence of central nuclei containing myofibers, but only 16 Gy increased the extracellular matrix volume. However, only 4x4 Gy increased muscle 4-hydroxynonenal expression. While both 16 Gy and 4x4 Gy decreased IIB myofiber mean cross-sectional area (CSA), only 16 Gy decreased IIA myofiber CSA. 16 Gy increased the incidence of small diameter IIA and IIB myofibers, while 4x4 Gy only increased the incidence of small diameter IIB myofibers. Both treatments decreased the frequency and CSA of low succinate dehydrogenase activity (SDH) fibers. Only 16 Gy increased the incidence of small diameter myofibers having high SDH activity. Neither treatment altered muscle signaling related to protein turnover or oxidative metabolism.ConclusionsCollectively, these results demonstrate that radiation dose differentially affects muscle remodeling, and these effects appear to be related to fiber type and oxidative metabolism

The role country of birth plays in receiving disability pensions in relation to patterns of health care utilisation and socioeconomic differences: a multilevel analysis of Malmo, Sweden

BACKGROUND: People of low socioeconomic status have worse health and a higher probability of being granted a disability pension than people of high socioeconomic status. It is also known that public and private general physicians and public and private specialists have varying practices for issuing sick leave certificates (which, if longstanding, may become the basis of disability pensions). However, few studies have investigated the influence of a patient's country of birth in this context. METHODS: We used multilevel logistic regression analysis with individuals (first level) nested within countries of birth (second level). We analysed the entire population between the ages of 40 and 64 years (n = 80 212) in the city of Malmo, Sweden, in 2003, and identified 73% of that population who had visited a physician at least once during that year. We studied the associations between individuals and country of birth socioeconomic characteristics, as well as individual utilisation of different kinds of physicians in relation to having been granted a disability pension. RESULTS: Living alone (OR(women )= 1.72, 95% CI: 1.62–1.82; OR(men )= 2.64, 95% CI: 2.46–2.83) and having limited educational achievement (OR(women )= 2.14, 95% CI: 2.00–2.29; OR(men )= 2.12, 95% CI: 1.98–2.28) were positively associated with having a disability pension. Utilisation of public specialists was associated with a higher probability (OR(women )= 2.11, 95% CI: 1.98–2.25; OR(men )= 2.16, 95% CI: 2.01–2.32) and utilisation of private GPs with a lower probability (OR(men )= 0.76, 95% CI: 0.69–0.83) of having a disability pension. However, these associations differed by countries of birth. Over and above individual socioeconomic status, men from middle income countries had a higher probability of having a disability pension (OR(men )= 1.61, 95% CI: 1.06–2.44). CONCLUSION: The country of one's birth appears to play a significant role in understanding how individual socioeconomic differences bear on the likelihood of receiving a disability pension and on associated patterns of health care utilisation