Prospective of study of gestational diabetes mellitus risk in relation to maternal recreation physical activity before and after pregnancy

Background: Gestational diabetes mellitus is common complications of pregnancy. Physical activity is associated with a lower risk of type 2 diabetes mellitus. The present study aimed to know association between physical activity and gestational diabetes mellitus in the first 20 weeks of their pregnancy.Methods: In the current case-control study, 50 pregnant females with gestational diabetes mellitus as the case group and 50 pregnant females as control group were selected. To diagnose gestational diabetes mellitus using diagnostic criteria. Females with abnormal oral glucose challenge test (>140mg/dL) were asked to perform the three-hour 100 g oral glucose tolerance test. The details of physical activity were collected by pregnancy physical activity questionnaire. Anthropometric and other data were recorded for all of the participants.Results: Females with low total physical activity at early pregnancy were at a significantly higher risk of developing gestational diabetes mellitus compared to the ones with higher levels of physical activity. After adjusting for age, body mass index (BMI), gravidity and a family history of diabetes, females with low physical activity during 20 weeks of pregnancy were at a significantly higher risk of developing gestational diabetes mellitus. Females with the low intensity of sedentary, light and moderate physical activity are at a higher risk of developing gestational diabetes mellitus compared to females with a higher intensity of sedentary, light and moderate physical activity.Conclusions: Females should be encouraged to do regular daily physical activity during pregnancy, if there is no specific contraindication to it.

Fibercoupled Ultrashortpulselaserbased Electronic Excitation Tagging Velocimetry

Transmission of intense ultrashort laser pulses through hollowcore fibers (HCFs) is investigated for moleculartagging velocimetry. A lowvacuumed HCF beamdelivery system is developed to transmit highpeakpower pulses. Vacuum pressure effects on transmission efficiency and nonlinear effects at the fiber output are studied for 100ps and 100fs laser beams. With a 0.1 bar vacuum in the fiber, transmission efficiency increases by ~30%, while spectral broadening is reduced. A 1mlong, 1mmcore metaldielectriccoated HCF can transmit ~45 mJ/pulse and ~2.9 mJ/pulse for 100ps laser pulses (at 532 nm) and 100fs laser pulses (at 810 nm), respectively. Proofofprinciple, singlelasershot, fibercoupled, ps and fslaserbased, nitrogen electronicexcitation tagging velocimetry is demonstrated in a free jet. Flow velocities are measured at 200 kHz to capture highfrequency flow events

100-ps-pulse-duration, 100-J burst-mode laser for kHz–MHz flow diagnostics

A high-speed, master-oscillator power-amplifier burst-mode laser with ∼100 ps pulse duration is demonstrated with output energy up to 110 J per burst at 1064 nm and second-harmonic conversion efficiency up to 67% in a KD*P crystal. The output energy is distributed across 100 to 10,000 sequential laser pulses, with 10 kHz to 1 MHz repetition rate, respectively, over 10 ms burst duration. The performance of the 100 ps burst-mode laser is evaluated and been found to compare favorably with that of a similar design that employs a conventional ∼8 ns pulse duration. The nearly transform-limited spectral bandwidth of 0.15 cm−1 at 532 nm is ideal for a wide range of linear and nonlinear spectroscopic techniques, and the 100 picosecond pulse duration is optimal for fiber-coupled spectroscopic measurements in harsh reacting-flow environments

Time- and frequency-dependent model of time-resolved coherent anti-Stokes Raman scattering (CARS) with a picosecond-duration probe pulse

The hybrid femtosecond/picosecond coherent anti-Stokes Raman scattering (fs/ps CARS) technique presents a promising alternative to either fs time-resolved or ps frequency-resolved CARS in both gas-phase thermometry and condensed-phase excited-state dynamics applications. A theoretical description of time-dependent CARS is used to examine this recently developed probe technique, and quantitative comparisons of the full time–frequency evolution show excellent accuracy in predicting the experimental vibrational CARS spectra obtained for two model systems. The interrelated timeand frequency-domain spectral signatures of gas-phase species produced by hybrid fs/ps CARS are explored with a focus on gas-phase N2 vibrational CARS, which is commonly used as a thermometric diagnostic of combusting flows. In particular, we discuss the merits of the simple top-hat spectral filter typically used to generate the ps-duration hybrid fs/ps CARS probe pulse, including strong discrimination against non-resonant background that often contaminates CARS signal. It is further demonstrated, via comparison with vibrational CARS results on a time-evolving solvated organic chromophore, that this top-hat probe-pulse configuration can provide improved spectral resolution, although the degree of improvement depends on the dephasing timescales of the observed molecular modes and the duration and timing of the narrowband final pulse. Additionally, we discuss the virtues of a frequency-domain Lorentzian probe-pulse lineshape and its potential for improving the hybrid fs/ps CARS technique as a diagnostic in high-pressure gas-phase thermometry applications

Comparison of Radiation Transport Codes, HZETRN, HETC and FLUKA, Using the 1956 Webber SPE Spectrum

Protection of astronauts and instrumentation from galactic cosmic rays (GCR) and solar particle events (SPE) in the harsh environment of space is of prime importance in the design of personal shielding, spacec raft, and mission planning. Early entry of radiation constraints into the design process enables optimal shielding strategies, but demands efficient and accurate tools that can be used by design engineers in every phase of an evolving space project. The radiation transport code , HZETRN, is an efficient tool for analyzing the shielding effectiveness of materials exposed to space radiation. In this paper, HZETRN is compared to the Monte Carlo codes HETC-HEDS and FLUKA, for a shield/target configuration comprised of a 20 g/sq cm Aluminum slab in front of a 30 g/cm^2 slab of water exposed to the February 1956 SPE, as mode led by the Webber spectrum. Neutron and proton fluence spectra, as well as dose and dose equivalent values, are compared at various depths in the water target. This study shows that there are many regions where HZETRN agrees with both HETC-HEDS and FLUKA for this shield/target configuration and the SPE environment. However, there are also regions where there are appreciable differences between the three computer c odes

DIRECT MEASUREMENTS OF COLLISIONALLY BROADENED (CO2_{2}-CO2_{2}) S-BRANCH RAMAN COHERENCE LIFETIMES OF CO2_{2}

Author Institution: Department of Chemistry, Purdue University, West Lafayette, IN 47907; Spectral Energies, LLC, 5100 Springfield Street, Suite 301, Dayton, OH 45431; Air Force Research Laboratory, Propulsion Directorate, Wright-Patterson AFB, OH 45433We report direct measurement of S-branch Raman coherence lifetimes of CO$_{2}$ due to CO$_{2}$-CO$_{2}$ collisions by employing picosecond time-resolved coherent anti-Stokes Raman scattering (CARS) spectroscopy. A custom-built, high-peak-power, nearly transform-limited ps laser system offers an ideal combination of frequency and temporal resolution for such measurements. The rotational S-branch transitions of CO$_{2}$ ground state [0,0$^{0}$,0] with rotational quantum number J$=0-52$ were simultaneously excited by using a broadband ($\sim$3-nm) laser pulse with a full-width-half-maximum (FWHM) of $\sim$100 ps. The coherence lifetimes of self-broadened CO$_{2}$ for a pressure range of 0.05-1.5 bar were directly measured by probing the rotational coherence with a nearly transform-limited, 80-ps-long laser pulse. The measured linewidth of J=6 and J=50 transitions are found to be $\sim$0.106$\pm$0.0002 and $\sim$0.070$\pm$0.0002, respectively. As expected, the energy-transfer from high J levels has a significantly longer coherence lifetime because of the inertia associated with higher angular momentum. These measurements are very significant for performing accurate thermometry or CO$_{2}$ concentration measurements in gas-phase reacting flows