Pulsational Analysis of the Cores of Massive Stars and its Relevance to Pulsar Kicks

The mechanism responsible for the natal kicks of neutron stars continues to be a challenging problem. Indeed, many mechanisms have been suggested, and one hydrodynamic mechanism may require large initial asymmetries in the cores of supernova progenitor stars. Goldreich, Lai, & Sahrling (1997) suggested that unstable g-modes trapped in the iron (Fe) core by the convective burning layers and excited by the $\epsilon$-mechanism may provide the requisite asymmetries. We perform a modal analysis of the last minutes before collapse of published core structures and derive eigenfrequencies and eigenfunctions, including the nonadiabatic effects of growth by nuclear burning and decay by both neutrino and acoustic losses. In general, we find two types of g-modes: inner-core g-modes, which are stabilized by neutrino losses and outer-core g-modes which are trapped near the burning shells and can be unstable. Without exception, we find at least one unstable g-mode for each progenitor in the entire mass range we consider, 11 M_{\sun} to 40 M_{\sun}. More importantly, we find that the timescales for growth and decay are an order of magnitude or more longer than the time until the commencement of core collapse. We conclude that the $\epsilon$-mechanism may not have enough time to significantly amplify core g-modes prior to collapse.Comment: 32 pages including 12 color figures and 2 tables, submitted to Ap

Low Sputum Smear Positive Tuberculosis among Pulmonary Tuberculosis Suspects in a Tertiary Hospital in Mwanza, Tanzania

Early diagnosis of tuberculosis (TB) and prompt initiation of treatment are essential for an effective tuberculosis control programme. In many resource limited settings microscopic diagnosis is still the pivotal tool in the diagnosis of pulmonary TB. This study aimed at evaluating laboratory microscopic diagnosis of tuberculosis in a tertiary hospital in Mwanza, Tanzania. This retrospective hospital based study reviewed consecutively from TB registry and patients’ files a total of 5,922 TB suspects who submitted their sputum for examination between January 2007 and May 2010 at Bugando Medical Centre (BMC). Among TB suspects (mean age=36.1±13.6 years) female accounted for 54.1% of the patients. The prevalence of HIV among TB patients was 59.4%. The sputum smear positivity rate among the TB suspects was 6.1%; the rate was higher in HIV positive than in HIV negative patients (9.9 % versus 3.2%, P-value < 0.001). The overall positivity rate for the first smear was 94.2% with an incremental percentage yield of 5.2% and 0.6% for the second and third smears, respectively. The study found that 28.6% of patients who were positive in the first smear did not return for the second smear. The risk factors among smear positive TB patients were co-illness (32.5%), previous history of TB (7.5%) and history of positive TB contact (4.7%). These findings also show that as CD4+ T Cells count increases, the quantity AFB in sputum smear also increase although not statistically significant. The sputum smear positivity rate at Bugando Medical Centre is low and more than a quarter of initial TB suspects who were positive in the first smear were lost to follow up posing a threat of continuous transmission of tuberculosis to the community. The finding of more sputum smear positivity rate among HIV positive than HIV negative patients at BMC requires a prospective study to ascertain whether it is a reality or a coincidence.\u

UC-177 Day Easy Phone Application

DayEasy is a phone application that is designed to promote clean eating and workout habits by providing services such as a calendar, workout planner, hydration and calorie journal, pedometer, fasting timer, and a meal planner. The application will have the functions to: • The user will be able to create an account. • The user will be able to change their password when they forget it. This will be done by sending an email. • The user will be able to save their sign in credentials. • The user will be able to view their daily schedule. • The user will be able to create new tasks. • These tasks are repeatable. • The user will be able to add how much water they drink in oz/ml • The user can set a daily drinking goal. • The user will be able to see how many steps they have taken. • The user can set a daily step goal. • The user will be able to plan their workout by selecting various customized movements. • The user will be able to select a movement (possibly a GIF) and see information about it. • The user will be able to go to muscle option and select a muscle part they want to work on and plan their workout. • The user will be able to plan their meals by keeping a journal. This journal will include calories. • The user will be able to pick a customized meal plan based on dietary selections. • The user will be able to add up their calories. • The user will be able to set a daily calorie goal

Relationships Between Indices of Macrovascular and Microvascular Function in Young, Black Women

Blacks (BL) exhibit an exaggerated prevalence of and mortality from cardiovascular disease (CVD) relative to other populations. Macro- and microvascular dysfunction is often a hallmark of heightened CVD risk, with both demonstrated in BL. However, data regarding this dysfunction remains sparse, particularly in BL women. Common indices of vascular function include flow-mediated dilation (FMD) and reactive hyperemia (RH) following a brief period of suprasystolic cuff occlusion and cutaneous thermal reactivity to local heating (LH). However, the relationship between these indices has not been established in BL women. PURPOSE: The present study aimed to test the relationship between indices of vascular function in BL women as assessed by FMD, RH, and LH. METHODS: To test this hypothesis, 6 white women (WW) and 6 BW (age: 22±2 vs. 21±3, respectively) were studied. FMD and RH were assessed following a period of suprasystolic cuff occlusion. Briefly, a rapid inflation cuff was secured just distal to the antecubital fossa for arterial occlusion. Blood velocity (Vmean; cm ∙ s-1) and vessel diameter (d; mm) were measured continuously via high-resolution, duplex Doppler ultrasound during a 2-min baseline, 5-min of cuff occlusion, and 3-min of recovery. FMD was determined as the percent dilation from baseline (%FMD) while RH was determined as the peak and area under the curve (AUC) responses for shear rate (8 ∙ Vmean ∙ d-1) and blood flow (Vmean ∙ π ∙ (d ∙ 20-1)2 ∙ 60). Cutaneous thermal reactivity was assessed using laser-Doppler flowmetry during a standard LH protocol and reported as cutaneous vascular conductance (CVC; red blood cell flux/mean arterial pressure). Following a baseline with local skin temperature clamped at 33°C, a 39°C heat stimulus was applied to induce cutaneous vasodilation for ~30-min. The sustained vasodilation at the end of heating is predominantly nitric oxide mediated and provides an index of microvascular function. As the LH component served as part of a larger intradermal microdialysis protocol, maximal blood flow responses were elicited via combined intradermal sodium nitroprusside (28mM) infusion and 43°C heating. CVC during the 39°C plateau was normalized to maximal CVC (%CVCmax) to account for intersite variability. Pearson correlations were then performed between the FMD, RH, and LH responses. RESULTS: Significant relationships were observed between %FMD and shear AUC (r = 0.89; P = 0.02), and blood flow AUC (r = 0.92; P = 0.01) in WW, but not in BW (r = 0.63; P = 0.18 and r = -0.24; P = 0.65, respectively). However, neither FMD nor RH correlated with the cutaneous blood flow responses to LH (P \u3e 0.05) in either WW or BW. CONCLUSION: These preliminary data suggest that FMD is highly correlated to some indices of RH in WW, but that this relationship does not hold in BW. Further, there appears to be no relationship between microvascular function as assessed by RH and LH in either population

The relationship between quality and economic value of fresh sweet potato and dried cassava products in Mwanza, Tanzania

This report outlines the relationship between quality and economic value for fresh sweet potato and dried cassava in the urban markets of Mwanza in north west Tanzania. These two crops form an increasingly important part of food security and, through the marketing of surpluses, of income generation for poor householders. The work reported in this report used a combination of participatory and more formal statistical methodologies in order to gauge relationships between quality and value of the marketed produce

Where are the Baryons?

New, high resolution, large-scale, cosmological hydrodynamic galaxy formation simulations of a standard cold dark matter model (with a cosmological constant) are utilized to predict the distribution of baryons at the present and at moderate redshift. It is found that the average temperature of baryons is an increasing function of time, with most of the baryons at the present time having a temperature in the range 10^{5-7} K. Thus, not only is the universe dominated by dark matter, but more than one half of the normal matter is yet to be detected. Detection of this warm/hot gas poses an observational challenge, requiring sensitive EUV and X-ray satellites. Signatures include a soft, cosmic X-ray background, apparent warm components in hot clusters due to both intrinsic warm intra-cluster gas and warm inter-cluster gas projected onto clusters along the line of sight, absorption lines in X-ray and UV quasar spectra [e.g., O VI (1032,1038)A lines, OVII 574 eV line], strong emission lines (e.g., O VIII 653 eV line) and low redshift, broad, low column density \lya absorption lines. We estimate that approximately 1/4 of the extragalactic soft X-ray background (SXRB) (at 0.7 keV) arises from the warm/hot gas, half of it coming from $z<0.65$ and three-quarters from $z<1.00$, so the source regions should be identifiable on deep optical images.Comment: ApJ in press, revised (fig 3 is in jpg). Whole paper including fig3.ps can be obtained at "http://astro.princeton.edu/~cen/PAPERS_TO_APPEAR/64

Adding Environmental Gas Physics to the Semi-Analytic Method for Galaxy Formation: Gravitational Heating

We present results of an attempt to include more detailed gas physics motivated from hydrodynamical simulations within semi-analytic models (SAM) of galaxy formation, focusing on the role that environmental effects play. The main difference to previous SAMs is that we include 'gravitational' heating of the intra-cluster medium (ICM) by the net surplus of gravitational potential energy released from gas that has been stripped from infalling satellites. Gravitational heating appears to be an efficient heating source able to prevent cooling in environments corresponding to dark matter halos more massive than $\sim 10^{13}$M$_{\odot}$. The energy release by gravitational heating can match that by AGN-feedback in massive galaxies and can exceed it in the most massive ones. However, there is a fundamental difference in the way the two processes operate. Gravitational heating becomes important at late times, when the peak activity of AGNs is already over, and it is very mass dependent. This mass dependency and time behaviour gives the right trend to recover down-sizing in the star-formation rate of massive galaxies. Abridged...Comment: replaced by accepted version to ApJ, some sections have been dropped and text has been added to others to include the referee's comments, several typos have been correcte

Meeting Forest Restoration Challenges: Using the Target Plant Concept

Meeting forest restoration challenges relies on successful establishment of plant materials (e.g., seeds, cuttings, rooted cuttings, or seedlings, etc.; hereafter simply “seedlingsâ€). The Target Plant Concept (TPC) provides a flexible framework that nursery managers and their clients can use to improve the survival and growth of these seedlings. The key tenets of the TPC are that (1) more emphasis is placed on how seedlings perform on the outplanting site rather than on nursery performance, (2) a partnership exists between the nursery manager and the client to determine the target plant based on site characteristics, and (3) that information gleaned from post-planting monitoring is used to improve subsequent plant materials. Through the nursery manager–client partnership, answers to a matrix of interrelated questions define a target plant to meet the reforestation or forest restoration objectives. These questions focus on project objectives; site characteristics, limiting factors, and possible mitigation efforts; species and genetic criteria; stocktype; outplanting tools and techniques; and outplanting window. We provide examples from the southeastern United States, Hawai‛i, and Lebanon on how the TPC process has improved performance of seedlings deployed for reforestation and forest restoration