Multibeam Laser Altimeter for Planetary Topographic Mapping

Laser altimetry provides an active, high-resolution, high-accuracy method for measurement of planetary and asteroid surface topography. The basis of the measurement is the timing of the roundtrip propagation of short-duration pulses of laser radiation between a spacecraft and the surface. Vertical, or elevation, resolution of the altimetry measurement is determined primarily by laser pulse width, surface-induced spreading in time of the reflected pulse, and the timing precision of the altimeter electronics. With conventional gain-switched pulses from solid-state lasers and nanosecond resolution timing electronics, submeter vertical range resolution is possible anywhere from orbital altitudes of approximately 1 km to altitudes of several hundred kilometers. Horizontal resolution is a function of laser beam footprint size at the surface and the spacing between successive laser pulses. Laser divergence angle and altimeter platform height above the surface determine the laser footprint size at the surface, while laser pulse repetition rate, laser transmitter beam configuration, and altimeter platform velocity determine the spacing between successive laser pulses. Multiple laser transmitters in a single laser altimeter instrument that is orbiting above a planetary or asteroid surface could provide across-track as well as along-track coverage that can be used to construct a range image (i.e., topographic map) of the surface. We are developing a pushbroom laser altimeter instrument concept that utilizes a linear array of laser transmitters to provide contiguous across-track and along-track data. The laser technology is based on the emerging monolithic combination of individual, 1-sq cm diode-pumped Nd:YAG laser pulse emitters. Details of the multi-emitter laser transmitter technology, the instrument configuration, and performance calculations for a realistic Discovery-class mission will be presented

High Energy Neutrinos and Photons from Curvature Pions in Magnetars

We discuss the relevance of the curvature radiation of pions in strongly magnetized pulsars or magnetars, and their implications for the production of TeV energy neutrinos detectable by cubic kilometer scale detectors, as well as high energy photons.Comment: 19 pages, 4 figures, to appear in JCA

The implications of climate change scenario selection for future streamflow projection in the Upper Colorado River Basin

The impact of projected 21st century climate conditions on streamflow in the Upper Colorado River Basin was estimated using a multi-model ensemble approach wherein the downscaled outputs of 112 future climate projections from 16 global climate models (GCMs) were used to drive a macroscale hydrology model. By the middle of the century, the impacts on streamflow range, over the entire ensemble, from a decrease of approximately 30% to an increase of approximately the same magnitude. Although prior studies and associated media coverage have focused heavily on the likelihood of a drier future for the Colorado River Basin, approximately 25 to 35% of the ensemble of runs, by 2099 and 2039, respectively, result in no change or increases in streamflow. The broad range of projected impacts is primarily the result of uncertainty in projections of future precipitation, and a relatively small part of the variability of precipitation across the projections can be attributed to the effect of emissions pathways. The simulated evolution of future temperature is strongly influenced by emissions, but temperature has a smaller influence than precipitation on flow. Period change statistics (i.e., the change in flow from one 30-yr period to another) vary as much within a model ensemble as between models and emissions pathways. Even by the end of the current century, the variability across the projections is much greater than changes in the ensemble mean. The relatively large ensemble analysis described herein provides perspective on earlier studies that have used fewer scenarios, and suggests that impact analyses relying on one or a few climate scenarios are unacceptably influenced by the choice of projections

Potential energy surfaces for CH bond cleavage reactions

Ab initio, multi-reference, configuration interaction calculations are reported for CH{sub 4}{leftrightarrow}CH{sub 3}+H, CH{sub 3}F{leftrightarrow}CH{sub 2}F+H, CH{sub 2}F{sub 2}{leftrightarrow}CHF{sub 2}+H, and CHF{sub 3}{leftrightarrow}CF{sub 3}+H. Two equivalent, barrier-less paths are found for the CH{sub 3}+H recombination, two inequivalent, barrier-less paths are found for the CH{sub 2}F+H and CHF{sub 2}+H recombinations (depending on which side of the radical the H atom approaches), and only one barrier-less path is found for the CF{sub 3}+H recombination. Minimum energy path for H atom approaching CF{sub 3} from the concave side is predicted to have a barrier of 27 kcal/mole. Both minimum energy path energies and transitional frequencies as function of R{sub CH} for all 4 reactions are predicted to be similar

The responsiveness of the uterine fibroid symptom and health-related quality of life questionnaire (UFS-QOL)

Abstract Background A number of noninvasive alternatives to hysterectomy have become available as treatments for uterine fibroids. These alternative therapies, however, may not relieve all symptoms. Consequently, the need for patient-reported outcomes to assess symptom reduction of uterine fibroids has become increasingly important to evaluate the clinical success of patients who choose these alternative therapies. The purpose of the study was to examine the responsiveness of the Uterine Fibroid Symptom and Health-Related Quality of Life Questionnaire (UFS-QOL) with treatment of uterine fibroids. Methods The responsiveness of the UFS-QOL was assessed as a post-hoc analysis of patients treated with MRI-guided focused ultrasound thermal ablation (MRgFUS) for uterine fibroids. The UFS-QOL and SF-36 were completed at baseline and months 1, 3, and 6. Patient perceived overall treatment effect (OTE) was assessed at month 3, while satisfaction with treatment was collected at month 6. The responsiveness of the UFS-QOL was examined using effect sizes and change scores by patient-reported overall treatment effect and satisfaction. Results A total of 102 women with complete UFS-QOL data were included in the analysis; the mean age was 45 years and 79% were Caucasian. From baseline to 6 months, significant improvements were observed in UFS-QOL Symptom Severity and all Health-Related Quality of Life (HRQL) subscale scores (p Conclusion The UFS-QOL is responsive to treatment for uterine fibroids and is a useful outcome measure for uterine-sparing uterine fibroid treatments.</p

Compton Scattering in Ultra-Strong Magnetic Fields: Numerical and Analytical Behavior in the Relativistic Regime

This paper explores the effects of strong magnetic fields on the Compton scattering of relativistic electrons. Recent studies of upscattering and energy loss by relativistic electrons that have used the non-relativistic, magnetic Thomson cross section for resonant scattering or the Klein-Nishina cross section for non-resonant scattering do not account for the relativistic quantum effects of strong fields ($> 4 \times 10^{12}$ G). We have derived a simplified expression for the exact QED scattering cross section for the broadly-applicable case where relativistic electrons move along the magnetic field. To facilitate applications to astrophysical models, we have also developed compact approximate expressions for both the differential and total polarization-dependent cross sections, with the latter representing well the exact total QED cross section even at the high fields believed to be present in environments near the stellar surfaces of Soft Gamma-Ray Repeaters and Anomalous X-Ray Pulsars. We find that strong magnetic fields significantly lower the Compton scattering cross section below and at the resonance, when the incident photon energy exceeds $m_ec^2$ in the electron rest frame. The cross section is strongly dependent on the polarization of the final scattered photon. Below the cyclotron fundamental, mostly photons of perpendicular polarization are produced in scatterings, a situation that also arises above this resonance for sub-critical fields. However, an interesting discovery is that for super-critical fields, a preponderance of photons of parallel polarization results from scatterings above the cyclotron fundamental. This characteristic is both a relativistic and magnetic effect not present in the Thomson or Klein-Nishina limits.Comment: AASTeX format, 31 pages included 7 embedded figures, accepted for publication in The Astrophysical Journa

An intraoperative surprise : occult case of non-functional parathyroid carcinoma

Parathyroid carcinoma (PC) exists in <1% of patients with hyperparathyroidism (Figure 1) and typically presents with a robust constellation of findings that rarely go unnoticed. Mean serum parathyroid hormone (PTH) concentrations are commonly 3-to 10-fold higher than the upper limit of normal with a mean serum calcium concentration that frequently exceeds 14 mg/dL. PCs also tend to metastasize to cervical lymph nodes (30%) which is a distinctly ominous sign when associated with this rare pathology as compared to its benign counterpart, parathyroid adenomas. Non-functioning parathyroid carcinomas (NPC), less than 10% of PCs, are exceptionally rare, and can more closely resemble parathyroid adenoma/hyperplasia on preoperative workup further obscuring diagnosis. This disease represents a unique subset of PCs that are rarely addressed in the literature

Caring for the caregiver: Why policy must shift from addressing needs to enabling caregivers to flourish

Policies supporting caregivers (“caregiver policies”) are limited in the extent to which they meet the needs of those who care for others. Where policies do exist, they focus on relieving the burdens associated with caring or the needs of the person they care for, rather than consider the holistic needs of the caregiver that would enable them to flourish. We argue that the established approach to caregiver policies reflects a policy failure, requiring a reassessment of current practice related to caregiver support. Often, caregiver policies target the care recipient rather than the caregiver's needs. Through a consultative exercise, we identified five areas of need that existing caregiver policies touch upon. Yet current approaches remain piecemeal and inadequate in a global context. Caregiver policies should not just relieve burden to the extent that caregivers can continue in the role, but they should support caregivers to flourish, and future work may benefit from drawing on related frameworks from positive psychology, such as the PERMA™ model; this is important for both policymakers and researchers

Developing sexual competence? Exploring strategies for the provision of effective sexualities and relationships education

School-based sexualities and relationships education (SRE) offers one of the most promising means of improving young people's sexual health through developing 'sexual competence'. In the absence of evidence on whether the term holds the same meanings for young people and adults (e.g. teachers, researchers, policy-makers), the paper explores 'adult' notions of sexual competence as construed in research data and alluded to in UK Government guidance on SRE, then draws on empirical research with young people on factors that affect the contexts, motivations and outcomes of sexual encounters, and therefore have implications for sexual competence. These data from young people also challenge more traditional approaches to sexualities education in highlighting disjunctions between the content of school-based input and their reported sexual experience. The paper concludes by considering the implications of these insights for developing a shared notion of what SRE is trying to achieve and suggestions for recognition in the content and approaches to SRE.</p