DMA precise time and time interval requirements

Defense Mapping Agency timing requirements ranging from milliseconds to tenths of nanoseconds and its use of geodetic astronomy and satellite geodesy programs are discussed in detail

Ultraviolet Absorption and Luminescence Investigations

Ultraviolet photographic system for remote detection of luminescent minerals and rocks and discriminating among nonluminescent materials on basis of ultraviolet absorptio

Efficacy of subcutaneous electrocardiogram leads for synchronous timing and aortic root cannulation for chronic counterpulsation therapy.

Background: Counterpulsation devices (CPD) require electrocardiogram (ECG) lead implantation for timing device filling and ejection with the native heart. Non- implantable leads limit the scope of CPD treatment to short-term therapy. Standard transvenous/epicardial ECG leads increase the invasiveness of therapy. Methods: To overcome these limitations, subcutaneous ECG leads were tested in chronic (n=6) and acute (n=5) bovine models. ECG waveforms from clinical- grade epicardial (control) leads and subcutaneous (test) leads were simultaneously recorded resulting in 830 data epochs (30-s each) for a total of 44,614 heart beats. Device triggering using R-wave detection was calculated for each lead type and compared. Additionally, the hemodynamic benefits of CPD with aortic cannulation (n=5) was investigated during normal and pharmacologically-induced heart failure, hypertension, and hypotension test conditions. Results: The subcutaneous leads provided 98.9% positive predictive value and 98.9% sensitivity compared to the epicardial ECG leads. Out of 40 subcutaneous leads implanted in chronic animals, lead migration (sensing-end movement \u3e0.5cm, n=1) and lead fracture (n=1) were observed in two leads but did not adversely impact triggering efficacy due to lead redundancy. The CPD vii cannulated to the aorta showed diminished left ventricular (LV) external work, LV end diastolic volume, and LV end systolic volume during 1:1 support compared to baseline in pharmacologically induced heart failure (HF). The CPD also augmented cardiac output, aortic mean pressure, aortic pulse pressure, and mean coronary artery flow. Conclusion: These findings demonstrate the efficacy of chronic, subcutaneous ECG leads for CPD timing. The hemodynamic feasibility of the CPD cannulated to the aorta is equivalent or better than subclavian artery cannulation because of the proximity to the heart, which may increase the size of CPD patient population for warranted cases

Development of TPS flight test and operational instrumentation

Thermal and flow sensor instrumentation was developed for use as an integral part of the space shuttle orbiter reusable thermal protection system. The effort was performed in three tasks: a study to determine the optimum instruments and instrument installations for the space shuttle orbiter RSI and RCC TPS; tests and/or analysis to determine the instrument installations to minimize measurement errors; and analysis using data from the test program for comparison to analytical methods. A detailed review of existing state of the art instrumentation in industry was performed to determine the baseline for the departure of the research effort. From this information, detailed criteria for thermal protection system instrumentation were developed

Continuum description of finite-size particles advected by external flows. The effect of collisions

The equation of the density field of an assembly of macroscopic particles advected by a hydrodynamic flow is derived from the microscopic description of the system. This equation allows to recognize the role and the relative importance of the different microscopic processes implicit in the model: the driving of the external flow, the inertia of the particles, and the collisions among them. The validity of the density description is confirmed by comparisons of numerical studies of the continuum equation with Direct Simulation Monte Carlo (DSMC) simulations of hard disks advected by a chaotic flow. We show that the collisions have two competing roles: a dispersing-like effect and a clustering effect (even for elastic collisions). An unexpected feature is also observed in the system: the presence of collisions can reverse the effect of inertia, so that grains with lower inertia are more clusterized.Comment: Final (strongly modified) version accepted in PRE; 6 pages, 3 figure

Effectiveness of a Faith-placed Cardiovascular Health Promotion Intervention for Rural Adults

Introduction: Cardiovascular disease (CVD) is the leading cause of mortality in the US. Further, rural US adults experience disproportionately high CVD prevalence and mortality compared to non-rural. Cardiovascular risk-reduction interventions for rural adults have shown short-term effectiveness, but long-term maintenance of outcomes remains a challenge. Faith organizations offer promise as collaborative partners for translating evidence-based interventions to reduce CVD. Methods: We adapted and implemented a collaborative, faith-placed, CVD risk-reduction intervention in rural Illinois. We used a quasi-experimental, pre-post design to compare changes in dietary and physical activity among participants. Intervention components included Heart Smart for Women (HSFW), an evidence-based program implemented weekly for 12 weeks followed by Heart Smart Maintenance (HSM), implemented monthly for two years. Participants engaged in HSFW only, HSM only, or both. We used regression and generalized estimating equations models to examine changes in outcomes after one year. Results: Among participants who completed both baseline and one-year surveys (n = 131), HSFW+HSM participants had significantly higher vegetable consumption (p = .007) and combined fruit/vegetable consumption (p = .01) compared to the HSM-only group at one year. We found no differences in physical activity. Conclusion: Improving and maintaining CVD-risk behaviors is a persistent challenge in rural populations. Advancing research to improve our understanding of effective translation of CVD risk-reduction interventions in rural populations is critical

Transient terahertz spectroscopy of excitons and unbound carriers in quasi two-dimensional electron-hole gases

We report a comprehensive experimental study and detailed model analysis of the terahertz dielectric response and density kinetics of excitons and unbound electron-hole pairs in GaAs quantum wells. A compact expression is given, in absolute units, for the complex-valued terahertz dielectric function of intra-excitonic transitions between the 1s and higher-energy exciton and continuum levels. It closely describes the terahertz spectra of resonantly generated excitons. Exciton ionization and formation are further explored, where the terahertz response exhibits both intra-excitonic and Drude features. Utilizing a two-component dielectric function, we derive the underlying exciton and unbound pair densities. In the ionized state, excellent agreement is found with the Saha thermodynamic equilibrium, which provides experimental verification of the two-component analysis and density scaling. During exciton formation, in turn, the pair kinetics is quantitatively described by a Saha equilibrium that follows the carrier cooling dynamics. The terahertz-derived kinetics is, moreover, consistent with time-resolved luminescence measured for comparison. Our study establishes a basis for tracking pair densities via transient terahertz spectroscopy of photoexcited quasi-two-dimensional electron-hole gases.Comment: 14 pages, 8 figures, final versio

Shared Determinants for Human Papillomavirus and COVID-19 Vaccination Intention: An Opportunity for Resource Consolidation

Purpose This study aimed at targeting shared factors that influence the prevention of multiple diseases, which can help address various health problems simultaneously. We identified correlates of human papillomavirus (HPV) vaccination that overlap with COVID-19 vaccination. Design Cross-sectional survey data. Setting Online Qualtrics recruitment panel. Subject Religious parents of 342 adolescents who were unvaccinated for HPV (response rate was 68.1%). Measures Outcome variables were COVID-19 vaccination intention for (1) self, (2) child, and (3) HPV vaccination intention for child. Independent variables were psychological factors. Covariates were sociodemographic and socioeconomic factors. Analysis We conducted multivariate linear regressions on each outcome variable after controlling for covariates. Result Some psychological correlates of HPV overlapped as protective factors for all three outcomes. Higher perceived vulnerability of child to HPV was associated with higher vaccination intention against COVID-19 for self (β = .37, 95% confidence interval [CI] = .25–.48), child (β = .32, .21–.44), and HPV for child (β = .38, .27–.49). Higher perceived response efficacy of HPV vaccine was associated with greater vaccination intention against COVID-19 for self (β = .46, .33–.59), child (β = .41, .28–.53), and HPV for child (β = .75, .64–.85). Conclusion Given the overlap in HPV and COVID-19 vaccination correlates, interventions should target shared factors that address both diseases to maximize public health efforts. A major limitation of this study is the inability to measure the actual vaccination behavior

Overcoming challenges: Going mobile with your own video models.

This is the publisher's version, also found here: http://cec.metapress.com/content/xtv27p4270444543/?p=368d1858244d4b8d957b1ecaf7e99f37&pi=

New combinations for Sonoran Desert plants

We provide new nomenclatural combinations for three Sonoran Desert plants: Opuntia engelmannii var. laevis (J.M. Coulter) Felger, Verrier, & Carnahan, comb. nov.; Parkinsonia florida subsp. peninsulare (Rose) Hawkins & Felger, comb. nov.; and Parkinsonia ×sonorae (Rose & I.M. Johnston ex I.M. Johnston) Hawkins & Felger, comb. nov