The dust, planetesimals and planets of HD 38529

HD 38529 is a post-main sequence G8III/IV star (3.5 Gyr old) with a planetary system consisting of at least two planets having Msin(i) of 0.8 MJup and 12.2 MJup, semimajor axes of 0.13 AU and 3.74 AU, and eccentricities of 0.25 and 0.35, respectively. Spitzer observations show that HD 38529 has an excess emission above the stellar photosphere, with a signal-to-noise ratio (S/N) at 70 micron of 4.7, a small excess at 33 micron (S/N=2.6) and no excess <30 micron. We discuss the distribution of the potential dust-producing planetesimals from the study of the dynamical perturbations of the two known planets, considering in particular the effect of secular resonances. We identify three dynamically stable niches at 0.4-0.8 AU, 20-50 AU and beyond 60 AU. We model the spectral energy distribution of HD 38529 to find out which of these niches show signs of harboring dust-producing plantesimals. The secular analysis, together with the SED modeling resuls, suggest that the planetesimals responsible for most of the dust emission are likely located within 20-50 AU, a configuration that resembles that of the Jovian planets + Kuiper Belt in our Solar System. Finally, we place upper limits (8E-6 lunar masses of 10 micron particles) to the amount of dust that could be located in the dynamically stable region that exists between the two planets (0.25--0.75 AU).Comment: 23 pages, including 1 table and 5 figures. Accepted for publication in Ap

Multiple Growth Mechanisms of Jadeite in Cuban Metabasite

Samples of rocks reported in the literature to be jadeite jade from the subduction-zone complex of the Escambray Massif in\ud central Cuba have been studied by optical and transmission electron microscopy, electron microprobe and hot-cathode cathodoluminescence\ud (CL) microscopy. Although these rocks are indeed rich in jadeite, the bulk rock composition generally conforms to\ud MORB, with Na2O enriched by . 3 wt% and CaO depleted by .2 wt%. Al2O3 contents are unchanged. These changes are attributed\ud to early pre-subduction spilitization of the ocean-floor protolith. Relics of magmatic augite preserving an ophitic texture are common.\ud Disequilibrium textures are the rule. Extensively recrystallized rocks show fine, felty intergrowths of predominantly Al-rich\ud glaucophane and jadeite, the latter with rims and patches of omphacite. TEM observations indicate extensive replacement of\ud pyroxene by amphibole. Glaucophane developed rims of magnesiokatophorite and edenite. Chlorite and epidote are also present.\ud Late development of actinolite, chlorite, epidote and albite is observed. Quartz is present. Less recrystallized samples with numerous\ud large (.1.5 mm) grains of augite show several types of sodic and sodic-calcic clinopyroxene development: (1) Topotactic\ud replacement of magmatic pyroxene by jadeite and omphacite along a broad front encroaching upon the augite grain from the rock\ud matrix. Jadeite dominates where presumably plagioclase was formerly present. Omphacite dominates where augite is internally\ud replaced along cleavage and fractures. Late chlorite, taramite and ferropargasite replace these pseudomorphs. (2) Former plagioclase\ud laths of the ophitic fabric are replaced by jadeite together with lesser omphacite in epitactic relationship with the enclosing augite.\ud Former plagioclase-augite grain boundaries remain preserved. Late pumpellyite is associated with the omphacite. (3) Jadeite þ\ud omphacite þ pumpellyite þ chlorite with irregular grain boundaries dominate in the rock matrix between the augite relics, with\ud idiomorphic crystals of epidote scattered throughout and in chlorite–epidote clusters. Pumpellyite is interpreted to be a late retrograde\ud product. Quartz is present. (4) Jadeite þ omphacite þ chlorite assemblages, in which monomineralic sheaf-like jadeite aggregates are\ud common, fill very thin (500–1500 mm) fractures criss-crossing the sample, including ophitic augite remnants. Cathodoluminescence\ud microscopy shows that jadeite in the veins is distinctly different from CL in the other types of jadeite, showing features like oscillatory\ud growth zoning indicative of crystallization from a fluid. Generally omphacite develops irregularly along jadeite rims, but recrystallization\ud may lead to pairs with straight grain boundaries suggestive of phase equilibration. Comparison with published solvus\ud relationships suggests temperatures of 425–500 C. This unusual occurrence of different types of jadeite in a metabasic rock suggests\ud two contrasting sources. The first – in the rock matrix, as topotactic alteration of igneous pyroxene and as plagioclase replacement\ud epitactically growing on augite – can be explained as due to local domain equilibration in a rapidly subducted ‘‘spilitized’’ gabbroic\ud rock. The second, in very thin fracture fillings, conforms to an origin as a crystallization product from a pervasive fluid. Conceivably,\ud ‘‘pooling’’ of the fluids flowing through the fractures in larger cavities could lead to larger masses of jadeitite. These have not yet been\ud conclusively documented in the Escambray Massif

Real Time Quantitative Radiological Monitoring Equipment for Environmental Assessment

The Idaho National Laboratory (INL) has developed a suite of systems that rapidly scan, analyze, and characterize radiological contamination in soil. These systems have been successfully deployed at several Department of Energy (DOE) laboratories and Cold War Legacy closure sites. Traditionally, these systems have been used during the characterization and remediation of radiologically contaminated soils and surfaces; however, subsequent to the terrorist attacks of September 11, 2001, the applications of these systems have expanded to include homeland security operations for first response, continuing assessment and verification of cleanup activities in the event of the detonation of a radiological dispersal device. The core system components are a detector, a spectral analyzer, and a global positioning system (GPS). The system is computer controlled by menu-driven, user-friendly custom software designed for a technician-level operator. A wide variety of detectors have been used including several configurations of sodium iodide (NaI) and high-purity germanium (HPGe) detectors, and a large area proportional counter designed for the detection of x-rays from actinides such as Am-241 and Pu-238. Systems have been deployed from several platforms including a small all-terrain vehicle (ATV), hand-pushed carts, a backpack mounted unit, and an excavator mounted unit used where personnel safety considerations are paramount. The INL has advanced this concept, and expanded the system functionality to create an integrated, field-deployed analytical system through the use of tailored analysis and operations software. Customized, site specific software is assembled from a supporting toolbox of algorithms that streamline the data acquisition, analysis and reporting process. These algorithms include region specific spectral stripping, automated energy calibration, background subtraction, activity calculations based on measured detector efficiencies, and on-line data quality checks and measures. These analyses are combined to provide real-time areal activity and coverage maps that are displayed to the operator as the survey progresses. The flexible functionality of the INL systems are well suited to multiple roles supporting homeland security needs

A Prospective Observational Study of Antihemophilic Factor (Recombinant) Prophylaxis Related to Physical Activity Levels in Patients with Hemophilia A in the United States (SPACE)

Introduction: High collision-risk physical activity can increase bleeding risk in people with hemophilia A, as can increasing the time between factor VIII (FVIII) administration and physical activity. FVIII prophylaxis may be tailored to planned activities to prevent activity-related bleeding. Aim: To explore the relationship between physical activity levels, FVIII infusion timing, and occurrence of bleeding in patients with severe/moderately severe hemophilia A without FVIII inhibitors receiving antihemophilic factor (recombinant) (rAHF; ADVATE®; Baxalta US Inc., a Takeda company, Lexington, MA, USA). Methods: SPACE was a 6-month, prospective, multicenter, observational outcomes study (NCT02190149). Enrolled patients received an eDiary application and a wearable activity tracker, which recorded physical activity, rAHF infusion, and occurrence of bleeding. Physical activity risks were ranked using National Hemophilia Foundation criteria. Results: Fifty-four patients aged 11– 58 years (n = 47 prophylaxis, n = 7 on-demand) were included in the analysis. Patients had a mean (SD) 8.14 (10.94) annualized bleeding rate, and recorded 4980 intervals between an rAHF infusion and physical activity; 1759 (35.3%) of these intervals were ≤ 24 hours. Analysis of recorded eDiary data showed that the risk of activity-related bleeding did not significantly increase with time between last infusion and activity, but did increase with higher-risk physical activities. Analysis of activity tracker recorded data showed that the risk of bleeding reported by patients as spontaneous increased with prolonging time (≤ 24 to \u3e 24 hours) from last infusion to physical activity start (odds ratio 2.65, p \u3c 0.05). Joint health data collected at baseline were not included in the regression analysis because of small sample size; therefore the study could not assess whether patients with more joint disease at baseline were at higher risk of injury-related and reported spontaneous occurrence of bleeding. Conclusion: These results show that activities with a high risk of collision lead to an increased risk of bleeding. Further investigation is warranted to explore potential benefits of FVIII infusion timing to reduce the risks of activity-related occurrence of bleeding

Giant thermally-enhanced electrostriction and polar surface phase in La2Mo2O9 oxygen ion conductors

Ferroelectrics possess spontaneous electric polarization at macroscopic scales which nonetheless imposes strict limitations on the material classes. Recent discoveries of untraditional symmetry-breaking phenomena in reduced material dimensions have indicated feasibilities to extend polar properties to broader types of materials, potentially opening up the freedom for designing materials with hybrid functionalities. Here, we report the unusual electromechanical properties of La2Mo2O9 (LAMOX) oxygen ion conductors, systematically investigated at both bulk and surface length levels. We first observed giant electrostriction effects in La2Mo2O9 bulk ceramics that are thermally enhanced in concert with their low-energy oxygen-vacancy hopping dynamics. Moreover, while no clear bulk polarization was detected, the surface phases of LAMOX were found to be manifestly polar, likely originating from the coupling between the intrinsic structural flexibilities with strain gradients (i.e., flexoelectricity) and/or chemical heterogeneities present in the materials. These findings identify La2Mo2O9 as a promising electromechanical material system and suggest that the flexible structural and chemical configurations in ionically active materials could enable fundamentally different venues to accommodate electric polarization.Q.L. and H.W. were supported by the US Department of Energy, Office of Science, Materials Science and Engineering Division. T.L. and Y.L. acknowledge the support of the Australian Research Council (ARC) in the form of Discovery Projects (DP160104780). N.L. was supported by the Eugene P. Wigner Fellowship program at ORNL (No. DE-AC05-00OR22725). The PFM experiments were performed at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility at Oak Ridge National Laboratory (ORNL). The use of Advanced Photon Source was supported by the US DOE, Basic Energy Science under Contract No. DE-AC02-06CH11357

Octupole transitions in the 208Pb region

The 208Pb region is characterised by the existence of collective octupole states. Here we populated such states in 208Pb + 208Pb deep-inelastic reactions. γ-ray angular distribution measurements were used to infer the octupole character of several E3 transitions. The octupole character of the 2318 keV 17− → 14+ in 208Pb, 2485 keV 19/2 − → 13/2 + in 207Pb, 2419 keV 15/2 − → 9/2 + in 209Pb and 2465 keV 17/2 + → 11/2 − in 207Tl transitions was demonstrated for the first time. In addition, shell model calculations were performed using two different sets of two-body matrix elements. Their predictions were compared with emphasis on collective octupole states.This work is supported by the Science and Technology Facilities Council (STFC), UK, US Department of Energy, Office of Nuclear Physics, under Contract No. DEAC02-06CH11357 and DE-FG02-94ER40834, NSF grant PHY-1404442

Giant thermally-enhanced electrostriction and polar surface phase in La2Mo2O9 oxygen ion conductors

Ferroelectrics possess spontaneous electric polarization at macroscopic scales which nonetheless imposes strict limitations on the material classes. Recent discoveries of untraditional symmetry-breaking phenomena in reduced material dimensions have indicated feasibilities to extend polar properties to broader types of materials, potentially opening up the freedom for designing materials with hybrid functionalities. Here, we report the unusual electromechanical properties of La2Mo2O9 (LAMOX) oxygen ion conductors, systematically investigated at both bulk and surface length levels. We first observed giant electrostriction effects in La2Mo2O9 bulk ceramics that are thermally enhanced in concert with their low-energy oxygen-vacancy hopping dynamics. Moreover, while no clear bulk polarization was detected, the surface phases of LAMOX were found to be manifestly polar, likely originating from the coupling between the intrinsic structural flexibilities with strain gradients (i.e., flexoelectricity) and/or chemical heterogeneities present in the materials. These findings identify La2Mo2O9 as a promising electromechanical material system and suggest that the flexible structural and chemical configurations in ionically active materials could enable fundamentally different venues to accommodate electric polarization