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Optical phase curves of hot Jupiters can reveal global scattering properties. We implemented a Bayesian inference framework for optical phase curves with flux contributions from: reflected light from a potentially inhomogeneous atmosphere, thermal emission, ellipsoidal variations, Doppler beaming, and stellar rotation via a Gaussian process in the time domain. We probed for atmospheric homogeneity and time variability using the reflected light inferences for highly precise Kepler light curves of five hot Jupiters. We also investigated the scattering properties that constrain the most likely condensates in the inhomogeneous atmospheres. Cross validation prefers inhomogeneous albedo distributions for Kepler-7 b and Kepler-41 b, and a weak preference for inhomogeneity for KOI-13 b. None of the five planets exhibit significant variations in geometric albedo on 1-yr timescales, in agreement with theoretical expectations. We show that analytic reflected light phase curves with isotropic multiple scattering are in excellent agreement with full Rayleigh multiple scattering calculations, allowing for accelerated and analytic inference. In a case study of Kepler-41 b, we identified perovskite, forsterite, and enstatite as possible scattering species consistent with the reflected light phase curves, with condensate particle radii in the range 0.01–0.1 µm. [ABSTRACT FROM AUTHOR]

The National Student Clearinghouse (NSC) Research Center reports that 48 percent of all students begin their postsecondary education at community colleges--15 percentage points more than the number of students who begin their postsecondary education at four-year public institutions. It's easy to explain why. Access is easier because admission is open, community colleges are conveniently located, and they cost less. The NSC estimates that only approximately 25 percent of these students end up transferring to four-year institutions within six years; among those who do, 45 percent transfer more than once (AAC&U 2015). Evidence indicates that despite their desired outcome of earning a bachelor's degree, many students never do so because transferring from one institution to another remains an opaque, convoluted, and confusing process. Community College students soon discover that lower-division prerequisites, general education courses, and supporting course requirements vary significantly from one four-year institution to another. What is needed is a student-focused solution. Some community colleges and four-year institutions have signed formal agreements offering transfer admission guarantees (TAGs) or dual enrollment programs. TAGs guarantee admission to transfer students who complete an academic contract that specifies certain requirements a student must complete by the time of transfer; typically, they require students to have regular conversations with a community college or four-year advisor to verify that they are on track and making satisfactory academic progress. Initiatives such as TAGs and dual enrollment require advance support services that help prospective transfer students plan their programs of study, select courses, and prepare for their transition to the four-year campus's academic and social culture. This article explores the details involved in designing, implementing, and managing advanced transfer policy instruments.

Background: Pulsed reduced dose rate (PRDR) is an emerging radiotherapy technique for recurrent diseases. It is pertinent that the linac beam characteristics are evaluated for PRDR dose rates and a suitable dosimeter is employed for IMRT QA. Purpose: This study sought to investigate the pulse characteristics of a 6 MV photon beam during PRDR irradiations on a commercial linac. The feasibility of using EBT3 radiochromic film for use in IMRT QA was also investigated by comparing its response to a commercial diode array phantom. Methods: A plastic scintillator detector was employed to measure the photon pulse characteristics across nominal repetition rates (NRRs) in the 5–600 MU/min range. Film was irradiated with dose rates in the 0.033–4 Gy/min range to study the dose rate dependence. Five clinical PRDR treatment plans were selected for IMRT QA with the Delta4 phantom and EBT3 film sheets. The planned and measured dose were compared using gamma analysis with a criterion of 3%/3 mm. EBT3 film QA was performed using a cumulative technique and a weighting factor technique. Results: Negligible differences were observed in the pulse width and height data between the investigated NRRs. The pulse width was measured to be 3.15 ± 0.01 μs$\mu s$ and the PRF was calculated to be 3–357 Hz for the 5–600 MU/min NRRs. The EBT3 film was found to be dose rate independent within 3%. The gamma pass rates (GPRs) were above 99% and 90% for the Delta4 phantom and the EBT3 film using the cumulative QA method, respectively. GPRs as low as 80% were noted for the weighting factor EBT3 QA method. Conclusions: Altering the NRRs changes the mean dose rate while the instantaneous dose rate remains constant. The EBT3 film was found to be suitable for PRDR dosimetry and IMRT QA with minimal dose rate dependence. [ABSTRACT FROM AUTHOR]

The distribution of small-scale magnetic fields in stellar photospheres is an important ingredient in our understanding of the magnetism of low-mass stars. Their spatial distribution connects the field generated in the stellar interior with the outer corona and the large scale field, and thereby affects the space weather of planets. Unfortunately, we lack techniques that can locate them on most low-mass stars. One strategy is to localize field concentrations using the flares that occur in their vicinity. We explore a new method that adapts the spot simulation software fleck to study the modulation of flaring times as a function of active latitude. We use empirical relations to construct flare light curves similar to those available from Kepler and the Transiting Exoplanet Survey Satellite (TESS), search them for flares, and use the waiting times between flares to determine the location of active latitudes. We find that the mean and standard deviations of the waiting time distribution provide a unique diagnostic of flaring latitudes as a function of the number of active regions. Latitudes are best recovered when stars have three or less active regions that flare repeatedly, and active latitude widths below 20 deg; when either increases, the information about the active latitude location is gradually lost. We demonstrate our technique on a sample of flaring G dwarfs observed with the Kepler satellite, and furthermore suggest that combining ensemble methods for spots and flares could overcome the limitations of each individual technique for the localization of surface magnetic fields. [ABSTRACT FROM AUTHOR]

General circulation models (GCMs) provide context for interpreting multiwavelength, multiphase data of the atmospheres of tidally locked exoplanets. In the current study, the non-hydrostatic THOR GCM is coupled with the HELIOS radiative transfer solver for the first time, supported by an equilibrium chemistry solver (FastChem), opacity calculator (HELIOS-K), and Mie scattering code (LX-MIE). To accurately treat the scattering of radiation by medium-sized to large aerosols/condensates, improved two-stream radiative transfer is implemented within a GCM for the first time. Multiple scattering is implemented using a Thomas algorithm formulation of the two-stream flux solutions, which decreases the computational time by about 2 orders of magnitude compared to the iterative method used in past versions of HELIOS. As a case study, we present four GCMs of the hot Jupiter WASP-43b, where we compare the temperature, velocity, entropy, and streamfunction, as well as the synthetic spectra and phase curves, of runs using regular versus improved two-stream radiative transfer and isothermal versus non-isothermal layers. While the global climate is qualitatively robust, the synthetic spectra and phase curves are sensitive to these details. A THOR + HELIOS WASP-43b GCM (horizontal resolution of about 4 deg on the sphere and with 40 radial points) with multiwavelength radiative transfer (30 k-table bins) running for 3000 Earth days (864 000 time-steps) takes about 19–26 d to complete depending on the type of GPU. [ABSTRACT FROM AUTHOR]

Thermal phase curves of exoplanet atmospheres have revealed temperature maps as a function of planetary longitude, often by sinusoidal decomposition of the phase curve. We construct a framework for describing two-dimensional temperature maps of exoplanets with mathematical basis functions derived for a fluid layer on a rotating, heated sphere with drag/friction, which are generalisations of spherical harmonics. These basis functions naturally produce physically-motivated temperature maps for exoplanets with few free parameters. We investigate best practices for applying this framework to temperature maps of hot Jupiters by splitting the problem into two parts: (1) we constrain the temperature map as a function of latitude by tuning the basis functions to reproduce general circulation model outputs, since disk-integrated phase curve observations do not constrain this dimension; and (2) we infer the temperature maps of real hot Jupiters using original reductions of several Spitzer phase curves, which directly constrain the temperature variations with longitude. The resulting phase curves can be described with only three free parameters per bandpass – an efficiency improvement over the usual five or so used to describe sinusoidal decompositions of phase curves. Upon obtaining the hemispherically averaged day side and night side temperatures, the standard approach would be to use zero-dimensional box models to infer the Bond albedo and redistribution efficiency. We elucidate the limitation of these box models by demonstrating that negative Bond albedos may be obtained due to a choice of boundary condition on the night side temperature. We propose generalized definitions for the Bond albedo and heat redistribution efficiency for use with two-dimensional (2D) temperature maps. Open-source software called kelp is provided to efficiently compute the 2D temperature maps, phase curves, albedos and redistribution efficiencies. [ABSTRACT FROM AUTHOR]

Objective: To develop and conduct preliminary feasibility testing of a clinical screening instrument for early identification of COVID‐19 infection in older people residing in residential aged care services (RACS). Methods: A qualitative study was conducted using a multi‐modal approach involving examination of existing literature and national guidelines for COVID‐19 clinical screening, formulation of a discussion document with peer review and feasibility testing of a prototype screening tool. Results: Existing COVID‐19 clinical screening tools do not consider age‐related impacts on clinical presentation. The qualitative analysis identified the important clinical elements to include were a lower threshold for temperature, occurrence of a recent fall and change in functional status. The new elements also had to be simple and feasible to implement. Overall feedback was positive with all participants recommending the use of the new tool. Conclusion: A new screening tool for RACS residents was developed addressing the pathophysiological changes with ageing and atypical features of COVID‐19 infection. [ABSTRACT FROM AUTHOR]

Massive stars briefly pass through the yellow supergiant (YSG) phase as they evolve redward across the H-R diagram and expand into red supergiants (RSGs). Higher-mass stars pass through the YSG phase again as they evolve blueward after experiencing significant RSG mass loss. These post-RSG objects offer us a tantalizing glimpse into which stars end their lives as RSGs and why. One telltale sign of a post-RSG object may be an instability to pulsations, depending on the star's interior structure. Here we report the discovery of five YSGs with pulsation periods faster than 1 day, found in a sample of 76 cool supergiants observed by the Transiting Exoplanet Survey Satellite at a two-minute cadence. These pulsating YSGs are concentrated in an H-R diagram region not previously associated with pulsations; we conclude that this is a genuine new class of pulsating star, fast yellow pulsating supergiants (FYPSs). For each FYPS, we extract frequencies via iterative prewhitening and conduct a time-frequency analysis. One FYPS has an extracted frequency that is split into a triplet, and the amplitude of that peak is modulated on the same timescale as the frequency spacing of the triplet; neither rotation nor binary effects are likely culprits. We discuss the evolutionary status of FYPS and conclude that they are candidate post-RSGs. All stars in our sample also show the same stochastic low-frequency variability found in hot OB stars and attributed to internal gravity waves. Finally, we find four α Cygni variables in our sample, of which three are newly discovered. [ABSTRACT FROM AUTHOR]

One of the main science motivations for the ESA PLAnetary Transit and Oscillations (PLATO) mission is to measure exoplanet transit radii with 3 per cent precision. In addition to flares and starspots, stellar oscillations and granulation will enforce fundamental noise floors for transiting exoplanet radius measurements. We simulate light curves of Earth-sized exoplanets transiting continuum intensity images of the Sun taken by the Helioseismic and Magnetic Imager (HMI) instrument aboard the Solar Dynamics Observatory (SDO) to investigate the uncertainties introduced on the exoplanet radius measurements by stellar granulation and oscillations. After modelling the solar variability with a Gaussian process, we find that the amplitude of solar oscillations and granulation is of order 100 ppm – similar to the depth of an Earth transit – and introduces a fractional uncertainty on the depth of transit of 0.73 per cent assuming four transits are observed over the mission duration. However, when we translate the depth measurement into a radius measurement of the planet, we find a much larger radius uncertainty of 3.6 per cent. This is due to a degeneracy between the transit radius ratio, the limb darkening, and the impact parameter caused by the inability to constrain the transit impact parameter in the presence of stellar variability. We find that surface brightness inhomogeneity due to photospheric granulation contributes a lower limit of only 2 ppm to the photometry in-transit. The radius uncertainty due to granulation and oscillations, combined with the degeneracy with the transit impact parameter, accounts for a significant fraction of the error budget of the PLATO mission, before detector or observational noise is introduced to the light curve. If it is possible to constrain the impact parameter or to obtain follow-up observations at longer wavelengths where limb darkening is less significant, this may enable higher precision radius measurements. [ABSTRACT FROM AUTHOR]

We use archival daily spot coverage measurements from Howard et al. to study the rotational modulation of the Sun as though it were a distant star. A quasi-periodic Gaussian process measures the solar rotation period P rot = 26.3 ± 0.1 d, and activity cycle period P cyc = 10.7 ± 0.3 yr. We attempt to search for evidence of differential rotation in variations of the apparent rotation period throughout the activity cycle and do not detect a clear signal of differential rotation, consistent with the null results of the hare-and-hounds exercise of Aigrain et al. The full reconstructed solar light curve is available online. [ABSTRACT FROM AUTHOR]

Astrometry from Gaia will measure the positions of stellar photometric centroids to unprecedented precision.We show that the precision of Gaia astrometry is sufficient to detect starspotinduced centroid jitter for nearby stars in the Tycho-Gaia Astrometric Solution (TGAS) sample with magnetic activity similar to the young G-star KIC 7174505 or the active M4 dwarf GJ 1243, but is insufficient to measure centroid jitter for stars with Sun-like spot distributions. We simulate Gaia observations of stars with 10 year activity cycles to search for evidence of activity cycles, and find that Gaia astrometry alone likely cannot detect activity cycles for stars in the TGAS sample, even if they have spot distributions like KIC 7174505. We review the activity of the nearby low-mass stars in the TGAS sample for which we anticipate significant detections of spot-induced jitter. [ABSTRACT FROM AUTHOR]

American Military Technology: The Life Story of a Technology. By Barton C. Hacker with Margaret Vining. Baltimore: The Johns Hopkins University Press, 2006. Illustrations. Photographs. Glossary. Bibliography Index. Pp. xxi, [...]

War on Two Fronts: An Infantry Commander's War in Iraq and the Pentagon. By Christopher Hughes. Phila.: Casemate, 2007. Notes. Appendices. Index. Pp. xi, 309. $29.95 ISBN: 978-1-932033-81-6 This engaging [...]

The introduction of kikuyu (Cenchrus clandestinus (Hochst. ex Chiov.) Morrone) into Australia in 1918 has seen it become established and adapted to several geographic regions in a wide range of ecologies and environmental situations. After it naturalised to local conditions, researchers and farmers recognised the value of kikuyu in marginal and previously unproductive sites, where forage quality and quantity made this species popular with dairy farmers and pastoralists. Its versatility and prostrate, mat-forming characteristics also led to the adoption of kikuyu by local governments, homeowners and sporting organisations in urban environments as turf. Kikuyu has the ability to alleviate soil contamination and remediate soils, thus enhancing the use of previously unproductive land. However, the aggressive growth habit of the species, considered a problem in certain regions of the world, has led to a noxious weed classification in some states of the USA. This review includes information on expected changes to world agricultural and urban environments and the potential expanded role of kikuyu. The origin of kikuyu grass, genetic variability, tolerances to soil salinity and drought, and potential for genetic improvement are also discussed. [ABSTRACT FROM AUTHOR]

Background: Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are commonly used antihypertensive medications that have been reported to affect aberrant angiogenesis and the dysregulated inflammatory response. Because of such mechanisms, it was hypothesized that these medications might affect the tumor response to neoadjuvant radiation in patients with rectal cancer.Methods: One hundred fifteen patients who were treated with neoadjuvant radiation at the University of Wisconsin (UW) between 1999 and 2012 were identified. Univariate analyses were performed with anonymized patient data. In a second independent data set, 186 patients with rectal cancer who were treated with neoadjuvant radiation at the Queen's Medical Center of the University of Hawaii (UH) between 1995 and 2010 were identified. These data were independently analyzed as before. Multivariate analyses were performed with aggregate data.Results: Among patients taking ACEIs/ARBs in the UW data set, a significant 3-fold increase in the rate of pathologic complete response (pCR) to neoadjuvant therapy (52% vs 17%, P = .001) was observed. This finding was confirmed in the UH data set, in which a significant 2-fold-increased pCR rate (24% vs 12%, P = .03) was observed. Identified patient and treatment characteristics were otherwise balanced between patients taking and not taking ACEIs/ARBs. No significant effect was observed on pCR rates with other medications, including statins, metformin, and aspirin. Multivariate analyses of aggregate data identified ACEI/ARB use as a strong predictor of pCR (odds ratio, 4.02; 95% confidence interval, 2.06-7.82; P < .001).Conclusions: The incidental use of ACEIs/ARBs among patients with rectal cancer is associated with a significantly increased rate of pCR after neoadjuvant treatment. Cancer 2016;122:2487-95. © 2016 American Cancer Society. [ABSTRACT FROM AUTHOR]

Abstract: The INCOSE Model‐Based Conceptual Design (MBCD) Working Group was established in 2011 with the purpose of advancing the body of knowledge and practice of systems engineering (SE), through the development and application of model‐based systems engineering (MBSE) methodologies to the concept stage of a system's life‐cycle. The Working Group strives to achieve its vision through a series of activities conducted by members of the working group. One of these activities was to conduct a survey of people involved in MBCD, with the goal: To identify the issues associated with performing Conceptual Design and areas where MBCD has been successful. As part of this activity, two surveys, one in 2014 and one during 2015, have been conducted. This paper begins with an overview of the first survey and the need for a second survey that arose from the possibility of non‐response bias being present in the first survey's results. Following this, the results obtained from the second survey are presented, compared with the results from the first survey and discussed. The key insights the authors uncovered from the results, survey workshops, and symposium presentations on both surveys are also identified. The paper concludes with a discussion on how these results are being used to inform current MBCD WG activities and strategic planning. [ABSTRACT FROM AUTHOR]

The ABC's of Leadership. By David M. Hall. Santa Monica, Calif.: AuthorHouse, 2007. Bibliography. Pp. 97. $12.99 Paperback ISBN: 1-4259-6967-7. This collection of leadership lessons holds out great promise given [...]

Talking to the Enemy: Track Two Diplomacy in the Middle East and South Asia. By Dalia Dassa Kaye. Santa Monica, Calif.: RAND, 2007. Tables. Notes. Bibliography. Pp. xxv, 139. $25.00 [...]

The proliferation of normal cells is inhibited at confluence, but the molecular basis of this phenomenon, known as contact-dependent inhibition of proliferation, is unclear. We previously identified the neurofibromatosis type 2 (NF2) tumor suppressor Merlin as a critical mediator of contact-dependent inhibition of proliferation and specifically found that Merlin inhibits the internalization of, and signaling from, the epidermal growth factor receptor (EGFR) in response to cell contact. Merlin is closely related to the membrane–cytoskeleton linking proteins Ezrin, Radixin, and Moesin, and localization of Merlin to the cortical cytoskeleton is required for contact-dependent regulation of EGFR. We show that Merlin and Ezrin are essential components of a mechanism whereby mechanical forces associated with the establishment of cell–cell junctions are transduced across the cell cortex via the cortical actomyosin cytoskeleton to control the lateral mobility and activity of EGFR, providing novel insight into how cells inhibit mitogenic signaling in response to cell contact.

Background: Patients with grade 2 glioma exhibit highly variable survival. Re-irradiation for recurrent disease has limited mature clinical data. We report treatment results of pulsed reduced-dose rate (PRDR) radiation for patients with recurrent grade 2 glioma., Methods: A retrospective analysis of 58 patients treated with PRDR from 2000 to 2021 was performed. Radiation was delivered in 0.2 Gy pulses every 3 minutes encompassing tumor plus margin. Survival outcomes and prognostic factors on outcome were Kaplan-Meier and Cox regression analyses., Results: The median survival from the date of initial surgery was 8.6 years (95% CI: 5.5-11.8 years). 69% of patients showed malignant transformation to grade 3 (38%) or grade 4 (31%) glioma. Overall survival following PRDR was 12.6 months (95% CI: 8.3-17.0 months) and progression-free survival was 6.2 months (95% CI: 3.8-8.6 months). Overall response rate based on post-PRDR MRI was 36%. In patients who maintained grade 2 histology at recurrence, overall survival from PRDR was 22.0 months with 5 patients remaining disease-free, the longest at 8.2 and 11.4 years. PRDR was generally well tolerated., Conclusions: To the best of our knowledge, this is the largest reported series of patients with recurrent grade 2 gliomas treated with PRDR radiation for disease recurrence. We demonstrate promising survival and acceptable toxicity profiles following re-irradiation. In the cohort of patients who maintain grade 2 disease, prolonged survival (>5 years) is observed in selected patients. For the entire cohort, 1p19q codeletion, KPS, and longer time from initial diagnosis to PRDR were associated with improved survival., Competing Interests: C.M.H., B.A.M., W.A.T., A.B., P.T.G., H.I.R., and S.P.H. report no conflicts of interest. A.R.B. reports research funding from GE Healthcare and a grant from Siemens. A. Bhatia reports consulting fees from Servier Advisory Board, payment or honoraria from Wisconsin Association of Hematology and Oncology, and service as an Editor for Current Oncology Reports and Medlink Neurology., (Published by Oxford University Press on behalf of the Society for Neuro-Oncology and the European Association of Neuro-Oncology 2024.)

Increased breast density attributed to collagen I deposition is associated with a 4-6 fold increased risk of developing breast cancer. Here, we assessed cellular metabolic reprogramming of mammary carcinoma cells in response to increased collagen matrix density using an in vitro 3D model. Our initial observations demonstrated changes in functional metabolism in both normal mammary epithelial cells and mammary carcinoma cells in response to changes in matrix density. Further, mammary carcinoma cells grown in high density collagen matrices displayed decreased oxygen consumption and glucose metabolism via the tricarboxylic acid (TCA) cycle compared to cells cultured in low density matrices. Despite decreased glucose entry into the TCA cycle, levels of glucose uptake, cell viability, and ROS were not different between high and low density matrices. Interestingly, under high density conditions the contribution of glutamine as a fuel source to drive the TCA cycle was significantly enhanced. These alterations in functional metabolism mirrored significant changes in the expression of metabolic genes involved in glycolysis, oxidative phosphorylation, and the serine synthesis pathway. This study highlights the broad importance of the collagen microenvironment to cellular expression profiles, and shows that changes in density of the collagen microenvironment can modulate metabolic shifts of cancer cells., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)