347 research outputs found
Spiral Evolution in a Confined Geometry
Supported nanoscale lead crystallites with a step emerging from a
non-centered screw dislocation on the circular top facet were prepared by rapid
cooling from just above the melting temperature. STM observations of the top
facet show a nonuniform rotation rate and shape of the spiral step as the
crystallite relaxes. These features can be accurately modeled using curvature
driven dynamics, as in classical models of spiral growth, with boundary
conditions fixing the dislocation core and regions of the step lying along the
outer facet edge.Comment: 4 pages, 3 figures, to be published in Physical Review Letter
Pancreatic and multiorgan resection with inferior vena cava reconstruction for retroperitoneal leiomyosarcoma
Workload and Performance in FOPA: A Strategic Planning Interface for Air Traffic Control
The Flight Organizer Planning Aid (FOPA) interface was designed to aid strategic planning in air traffic control. In particular, FOPA was designed to address difficulties in solving en route sequencing problems (combining multiple streams of traffic into a single stream heading for a destination). We compared the planning performance of 12 full performance level air traffic controllers using either the FOPA interface or normal flight progress strips. Planning performance was significantly better when using FOPA; subjective workload was also reduced. The results indicate that a key advantage of FOPA lies in its dynamic linkage between the flight organizer screen where aircraft tokens can be categorized into color-coded blocks and their matching spatial representation on the radar.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
Knowledge and use of family planning among men in rural Uganda.
BACKGROUND: Unmet need for family planning exceeds 33% in Uganda. One approach to decreasing unmet need is promoting male involvement in family planning. Male disapproval of use of family planning by their female partners and misconceptions about side effects are barriers to family planning globally and in Uganda in particular. Researchers have conducted a number of qualitative studies in recent years to examine different aspects of family planning among Ugandan men. The present study aimed to quantify men's knowledge of family planning in rural Uganda to understand how better to involve men in couples' contraceptive decision-making, particularly in low-resource settings. METHODS: Data were derived from in-person, researcher-administered surveys of men in a rural agrarian district in Uganda (N = 178). Participant demographics and knowledge of family planning methods, side effects, and use were queried. Descriptive statistics were used for analysis. RESULTS: Men were 34 years of age on average (range 18-71) and about half (56%) had a primary school education or less. Ninety-eight percent reported any knowledge of family planning, with 73% of men reporting obtaining information via radio and only 43% from health workers. The most common method known by men was the male condom (72%), but more than half also knew of injections (54%) and pills (52%). Relatively few men reported knowing about the most effective reversible contraceptive methods, intrauterine devices and implants (both 16%). Men identified many common contraceptive side-effects, such as vaginal bleeding (31%), and misconceptions about side effects, such as increased risk of infertility and birth defects, were relatively uncommon (both < 10%). About half of all men reported ever using a family planning method (53%), and 40% reported current use. CONCLUSIONS: This study's quantitative results build on those of recent qualitative studies and provide information about the types of family planning information men are lacking and avenues for getting this information to them
Quantitative analysis of WC stars: Constraints on neon abundances from ISO/SWS spectroscopy
Neon abundances are derived in four Galactic WC stars -- gamma Vel (WR11,
WC8+O7.5III), HD156385 (WR90, WC7), HD192103 (WR135, WC8), and WR146 (WC5+O8) -
using mid-infrared fine structure lines obtained with ISO/SWS. Stellar
parameters for each star are derived using a non-LTE model atmospheric code
(Hillier & Miller 1998) together with ultraviolet (IUE), optical (INT, AAT) and
infrared (UKIRT, ISO) spectroscopy. In the case of gamma Vel, we adopt results
from De Marco et al. (2000), who followed an identical approach.
ISO/SWS datasets reveal the [NeIII] 15.5um line in each of our targets, while
[NeII] 12.8um, [SIV] 10.5um and [SIII] 18.7um are observed solely in gamma Vel.
Using a method updated from Barlow et al. (1988) to account for clumped winds,
we derive Ne/He=3-4x10^-3 by number, plus S/He=6x10^-5 for gamma Vel. Neon is
highly enriched, such that Ne/S in gamma Vel is eight times higher than cosmic
values. However, observed Ne/He ratios are a factor of two times lower than
predictions of current evolutionary models of massive stars. An imprecise
mass-loss and distance were responsible for the much greater discrepancy in
neon content identified by Barlow et al.
Our sample of WC5--8 stars span a narrow range in T* (=55--71kK), with no
trend towards higher temperature at earlier spectral type, supporting earlier
results for a larger sample by Koesterke & Hamann (1995). Stellar luminosities
range from 100,000 to 500,000 Lo, while 10^-5.1 < Mdot/(Mo/yr) < 10^-4.5,
adopting clumped winds, in which volume filling factors are 10%. In all cases,
wind performance numbers are less than 10, significantly lower than recent
estimates. Carbon abundances span 0.08 < C/He < 0.25 by number, while oxygen
abundances remain poorly constrained.Comment: 16 pages,7 figures accepted for MNRA
1995 CSREES Reports
The 1995 edition of the CSREES Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:
1. Factors Affecting the Quality of IQF Blueberries
2. Preventing the Bleeding of Blueberry Fruit in Bakery Products
3. Removing Water from Blueberries Before Freezing
4. Determination of Pesticide Residue Levels in Freshly Harvested and Processed Lowbush Blueberries
5. Industrial Ingredients from Cull Blueberries
6. Application of Heat as a Method of Controlling Secondary Pest Insects on Lowbush Blueberries
7. The Phenology and Biology of Bumble Bees, Bombus, spp., that Pollinate Lowbush blueberry, Vaccinium spp., in Maine
8. Pollination Ecology of Lowbush Blueberry in Maine
9. Effects of Irrigation on Lowbush Blueberry Yield
10. Effect of Brief Warming Treatments on Late Winter Low-Temperature Tolerance of Native Lowbush Blueberry
11. Correlation of Late-winter/Early-spring Cold Hardiness with Date of Flowering
12. Evaluation of Cold Tolerance of Opening Flowers of Lowbush Blueberry
13. Influence of Flower Delaying Sprays on Seasonal Variation of Low Temperature Tolerance in Lowbush Blueberry
14. Effect of Various Levels of Disbudding on Yield of Lowbush Blueberry
15. Effect of Boron and the Polyamine Putrescine on Lowbush Blueberry Fruit Set and Yield
16. Effect of Boron and the Polyamine Putrescine on Extending the Receptivity of Lowbush Blueberry Blossoms
17. Effect of Soil pH on Nutrient Uptake
18. Correcting Boron Deficiency - missing
19. Phosphorus Uptake
20. Evaluation of Hexazinone Formulation on Soil Movement and Weed Control
21. Effect of Time of Fall Pruning on Growth and Productivity of Blueberries
22. Hexazinone Ground Water Survey
23. Effect of hexazinone formulation on movement through the soil profile
24. Evaluation of Tribenuron Methyl for Bunchberry Control
25. Evaluation of Tribenuron Methyl Commercial Applications for Bunchberry Control
26. Effectiveness of Resin-Exchange Columns to Determine Efficacy in Removing Hexazinone from Well Water
27. Effect of Clopyralid for Vetch Control
28. Evaluation of Tribenuron Methyl/Velpar® Tank Mix for Bunchberry Control
29. Blueberry Extension Education Progra
Effectiveness of Denitrifying Bioreactors on Water Pollutant Reduction from Agricultural Areas
HighlightsDenitrifying woodchip bioreactors treat nitrate-N in a variety of applications and geographies.This review focuses on subsurface drainage bioreactors and bed-style designs (including in-ditch).Monitoring and reporting recommendations are provided to advance bioreactor science and engineering. Denitrifying bioreactors enhance the natural process of denitrification in a practical way to treat nitrate-nitrogen (N) in a variety of N-laden water matrices. The design and construction of bioreactors for treatment of subsurface drainage in the U.S. is guided by USDA-NRCS Conservation Practice Standard 605. This review consolidates the state of the science for denitrifying bioreactors using case studies from across the globe with an emphasis on full-size bioreactor nitrate-N removal and cost-effectiveness. The focus is on bed-style bioreactors (including in-ditch modifications), although there is mention of denitrifying walls, which broaden the applicability of bioreactor technology in some areas. Subsurface drainage denitrifying bioreactors have been assessed as removing 20% to 40% of annual nitrate-N loss in the Midwest, and an evaluation across the peer-reviewed literature published over the past three years showed that bioreactors around the world have been generally consistent with that (N load reduction median: 46%; mean ±SD: 40% ±26%; n = 15). Reported N removal rates were on the order of 5.1 g N m-3 d-1 (median; mean ±SD: 7.2 ±9.6 g N m-3 d-1; n = 27). Subsurface drainage bioreactor installation costs have ranged from less than 27,000, with estimated cost efficiencies ranging from less than 20 kg-1 N year-1 (although they can be as high as $48 kg-1 N year-1). A suggested monitoring setup is described primarily for the context of conservation practitioners and watershed groups for assessing annual nitrate-N load removal performance of subsurface drainage denitrifying bioreactors. Recommended minimum reporting measures for assessing and comparing annual N removal performance include: bioreactor dimensions and installation date; fill media size, porosity, and type; nitrate-N concentrations and water temperatures; bioreactor flow treatment details; basic drainage system and bioreactor design characteristics; and N removal rate and efficiency
American ginseng suppresses Western diet-promoted tumorigenesis in model of inflammation-associated colon cancer: role of EGFR
<p>Abstract</p> <p>Background</p> <p>Western diets increase colon cancer risk. Epidemiological evidence and experimental studies suggest that ginseng can inhibit colon cancer development. In this study we asked if ginseng could inhibit Western diet (20% fat) promoted colonic tumorigenesis and if compound K, a microbial metabolite of ginseng could suppress colon cancer xenograft growth.</p> <p>Methods</p> <p>Mice were initiated with azoxymethane (AOM) and, two weeks later fed a Western diet (WD, 20% fat) alone, or WD supplemented with 250-ppm ginseng. After 1 wk, mice received 2.5% dextran sulfate sodium (DSS) for 5 days and were sacrificed 12 wks after AOM. Tumors were harvested and cell proliferation measured by Ki67 staining and apoptosis by TUNEL assay. Levels of EGF-related signaling molecules and apoptosis regulators were determined by Western blotting. Anti-tumor effects of intraperitoneal compound K were examined using a tumor xenograft model and compound K absorption measured following oral ginseng gavage by UPLC-mass spectrometry. Effects of dietary ginseng on microbial diversity were measured by analysis of bacterial 16S rRNA.</p> <p>Results</p> <p>Ginseng significantly inhibited colonic inflammation and tumorigenesis and concomitantly reduced proliferation and increased apoptosis. The EGFR cascade was up-regulated in colonic tumors and ginseng significantly reduced EGFR and ErbB2 activation and Cox-2 expression. Dietary ginseng altered colonic microbial diversity, and bacterial suppression with metronidazole reduced serum compound K following ginseng gavage. Furthermore, compound K significantly inhibited tumor xenograft growth.</p> <p>Conclusions</p> <p>Ginseng inhibited colonic inflammation and tumorigenesis promoted by Western diet. We speculate that the ginseng metabolite compound K contributes to the chemopreventive effects of this agent in colonic tumorigenesis.</p
Real-time PCR-based assay to quantify the relative amount of human and mouse tissue present in tumor xenografts
<p>Abstract</p> <p>Background</p> <p>Xenograft samples used to test anti-cancer drug efficacies and toxicities in vivo contain an unknown mix of mouse and human cells. Evaluation of drug activity can be confounded by samples containing large amounts of contaminating mouse tissue. We have developed a real-time quantitative polymerase chain reaction (qPCR) assay using TaqMan technology to quantify the amount of mouse tissue that is incorporated into human xenograft samples.</p> <p>Results</p> <p>The forward and reverse primers bind to the same DNA sequence in the human and the mouse genome. Using a set of specially designed fluorescent probes provides species specificity. The linearity and sensitivity of the assay is evaluated using serial dilutions of single species and heterogeneous DNA mixtures. We examined many xenograft samples at various in vivo passages, finding a wide variety of human:mouse DNA ratios. This variation may be influenced by tumor type, number of serial passages in vivo, and even which part of the tumor was collected and used in the assay.</p> <p>Conclusions</p> <p>This novel assay provides an accurate quantitative assessment of human and mouse content in xenograft tumors. This assay can be performed on aberrantly behaving human xenografts, samples used in bioinformatics studies, and periodically for tumor tissue frequently grown by serial passage in vivo.</p
Validation of an arterial tortuosity measure with application to hypertension collection of clinical hypertensive patients
<p>Abstract</p> <p>Background</p> <p>Hypertension may increase tortuosity or twistedness of arteries. We applied a centerline extraction algorithm and tortuosity metric to magnetic resonance angiography (MRA) brain images to quantitatively measure the tortuosity of arterial vessel centerlines. The most commonly used arterial tortuosity measure is the distance factor metric (DFM). This study tested a DFM based measurement’s ability to detect increases in arterial tortuosity of hypertensives using existing images. Existing images presented challenges such as different resolutions which may affect the tortuosity measurement, different depths of the area imaged, and different artifacts of imaging that require filtering.</p> <p>Methods</p> <p>The stability and accuracy of alternative centerline algorithms was validated in numerically generated models and test brain MRA data. Existing images were gathered from previous studies and clinical medical systems by manually reading electronic medical records to identify hypertensives and negatives. Images of different resolutions were interpolated to similar resolutions. Arterial tortuosity in MRA images was measured from a DFM curve and tested on numerically generated models as well as MRA images from two hypertensive and three negative control populations. Comparisons were made between different resolutions, different filters, hypertensives versus negatives, and different negative controls.</p> <p>Results</p> <p>In tests using numerical models of a simple helix, the measured tortuosity increased as expected with more tightly coiled helices. Interpolation reduced resolution-dependent differences in measured tortuosity. The Korean hypertensive population had significantly higher arterial tortuosity than its corresponding negative control population across multiple arteries. In addition one negative control population of different ethnicity had significantly less arterial tortuosity than the other two.</p> <p>Conclusions</p> <p>Tortuosity can be compared between images of different resolutions by interpolating from lower to higher resolutions. Use of a universal negative control was not possible in this study. The method described here detected elevated arterial tortuosity in a hypertensive population compared to the negative control population and can be used to study this relation in other populations.</p
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