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Stimulation of bone growth with thrombin peptide derivatives
Disclosed is a method of stimulating bone growth at a site in a subject in need of osteoinduction. The method comprises the step of administering a therapeutically effective amount of an agonist of the non-proteolytically activated thrombin receptor to the site.Board of Regents, University of Texas Syste
Aerodynamic performance of flying discs
The purpose of this paper is to examine geometrical design influence of various types of flying discs on their flight performance from the aerodynamics perspective. The lift, drag and moment coefficients of the discs were measured experimentally using a wind tunnel. Three types of golf discs and four sets of simpler parametric discs were studied to analyze and isolate the effect of design factors on these aerodynamic characteristics. Full six degree-of-freedom simulations of the discs were performed to visualize their flight trajectories and attitudes. These simulations, combined with the experimental data, provide details on the well-known âS-shapedâ ground-path traced by a flying disc. This study reveals two key parameters to evaluate the flight performance of a disc: its coefficient of lift-to-drag ratio (CL/CD) and, more importantly, its coefficient of pitching moment (CM). The latter influences the tendency of the disc to roll from its intended path, and the former influences its throwing distance. The work suggests that to optimize the flight performance of a disc, the magnitudes and gradient of its CM should be minimized and its trim-point shifted from origin, while its CL/CD should be maximized with a flatter peak. In this study, the design parameters and the aerodynamic characteristics of various types of flying discs are analysed, compared and discussed in depth. Recommendations of design improvements to enhance the performance of any flying disc are offered as well
The VLT-FLAMES Tarantula Survey. IX. The interstellar medium seen through Diffuse Interstellar Bands and neutral sodium
The Tarantula Nebula (30 Dor) is a spectacular star-forming region in the
Large Magellanic Cloud, seen through gas in the Galactic Disc and Halo. Diffuse
Interstellar Bands offer a unique probe of the diffuse, cool-warm gas in these
regions. The aim is to use DIBs as diagnostics of the local interstellar
conditions, whilst at the same time deriving properties of the yet-unknown
carriers. Spectra of over 800 early-type stars from the VLT Flames Tarantula
Survey (VFTS) were analysed. Maps were created, separately, for the Galactic
and LMC absorption in the DIBs at 4428 and 6614 Ang and - in a smaller region
near the central cluster R136 - neutral sodium (Na I D); we also measured the
DIBs at 5780 and 5797 Ang. The maps show strong 4428 and 6614 Ang DIBs in the
quiescent cloud complex to the south of 30 Dor but weak absorption in the
harsher environments to the north (bubbles) and near the OB associations. The
Na maps show at least five kinematic components in the LMC and a shell-like
structure surrounding R136, and small-scale structure in the Milky Way. The
strengths of the 4428, 5780, 5797 and 6614 Ang DIBs are correlated, also with
Na absorption and visual extinction. The strong 4428 Ang DIB is present already
at low Na column density but the 6614, 5780 and 5797 Ang DIBs start to be
detectable at subsequently larger Na column densities. The relative strength of
the 5780 and 5797 Ang DIBs clearly confirm the Tarantula Nebula and Galactic
high-latitude gas to represent a harsh radiation environment. The resilience of
the 4428 Ang DIB suggests its carrier is large, compact and neutral. Structure
is detected in the distribution of cool-warm gas on scales between one and >100
pc in the LMC and as little as 0.01 pc in the Sun's vicinity. Stellar winds
from the central cluster R136 have created an expanding shell; some infalling
gas is also detected, reminiscent of a galactic "fountain".Comment: Accepted for publication in Astronomy and Astrophysic
Winter territoriality and its implications for the breeding ecology of White-throated Dippers Cinclus cinclus
Capsule: Pairs of White-throated Dippers Cinclus cinclus which defended winter territories bred earlier than non-territorial individuals, but there was no difference in reproductive success. Aims: The effect of winter territoriality on breeding ecology has rarely been studied in resident birds. We carried out a preliminary investigation of whether winter territorial behaviour and territory size affect the timing of reproduction, breeding territory size and reproductive success in a riverine bird, the White-throated Dipper. Methods: We monitored an individually marked population of White-throated Dippers in the UK. Wintering individuals were classified as either territorial or âfloatersâ according to their patterns of occurrence and behaviour, and their nesting attempts were closely monitored in the subsequent months. Winter and breeding territory sizes were measured by gently âpushingâ birds along the river and recording the point at which they turned back. Results: All birds defending winter territories did so in pairs, but some individuals changed partners before breeding. Territorial pairs that were together throughout the study laid eggs significantly earlier than pairs containing floaters and those comprising territorial birds that changed partners. However, there were no significant differences in clutch size, nestling mass or the number of chicks fledged. There was no relationship between winter territory length and lay date or any measure of reproductive success, although sample sizes were small. Winter territories were found to be significantly shorter than breeding territories. Conclusion: Winter territoriality may be advantageous because breeding earlier increases the likelihood that pairs will raise a second brood, but further study is needed. Territories are shorter in winter as altitudinal migrants from upland streams increase population density on rivers, but this may also reflect seasonal changes in nutritional and energetic demands
Effect of treatment of gestational diabetes mellitus on pregnancy outcomes
Copyright © 2005 Massachusetts Medical Society.Background: We conducted a randomized clinical trial to determine whether treatment of women with gestational diabetes mellitus reduced the risk of perinatal complications. Methods: We randomly assigned women between 24 and 34 weeksâ gestation who had gestational diabetes to receive dietary advice, blood glucose monitoring, and insulin therapy as needed (the intervention group) or routine care. Primary outcomes included serious perinatal complications (defined as death, shoulder dystocia, bone fracture, and nerve palsy), admission to the neonatal nursery, jaundice requiring phototherapy, induction of labor, cesarean birth, and maternal anxiety, depression, and health status. Results: The rate of serious perinatal complications was significantly lower among the infants of the 490 women in the intervention group than among the infants of the 510 women in the routine-care group (1 percent vs. 4 percent; relative risk adjusted for maternal age, race or ethnic group, and parity, 0.33; 95 percent confidence interval, 0.14 to 0.75; P=0.01). However, more infants of women in the intervention group were admitted to the neonatal nursery (71 percent vs. 61 percent; adjusted relative risk, 1.13; 95 percent confidence interval, 1.03 to 1.23; P=0.01). Women in the intervention group had a higher rate of induction of labor than the women in the routine-care group (39 percent vs. 29 percent; adjusted relative risk, 1.36; 95 percent confidence interval, 1.15 to 1.62; P<0.001), although the rates of cesarean delivery were similar (31 percent and 32 percent, respectively; adjusted relative risk, 0.97; 95 percent confidence interval, 0.81 to 1.16; P=0.73). At three months post partum, data on the womenâs mood and quality of life, available for 573 women, revealed lower rates of depression and higher scores, consistent with improved health status, in the intervention group. Conclusions: Treatment of gestational diabetes reduces serious perinatal morbidity and may also improve the womanâs health-related quality of life.Caroline A. Crowther, Janet E. Hiller, John R. Moss, Andrew J. McPhee, William S. Jeffries and Jeffrey S. Robinso
An Atlas of FUSE Sight Lines Toward the Magellanic Clouds
We present an atlas of 57 Large Magellanic Cloud (LMC) and 37 Small
Magellanic Cloud (SMC) observations obtained with the Far Ultraviolet
Spectroscopic Explorer (FUSE) satellite. The atlas highlights twelve
interstellar absorption line transitions at a resolution of ~15 km/s. These
transitions cover a broad range of temperatures, ionization states, and
abundances. The species included are OVI, which probes hot (T~3x10^5 K) ionized
gas; CIII and FeIII, which probe warm (T~10^4 K) ionized gas; SiII, PII, CII,
FeII, and OI, warm neutral gas; and six different molecular hydrogen
transitions, which trace cold (T<=500 K) gas. We include Schmidt Halpha CCD
images of the region surrounding each sight line showing the morphology of warm
ionized gas in the vicinity, along with continuum images near each FUSE
aperture position. Finally, we present several initial scientific results
derived from this dataset on the interstellar medium of the Magellanic Clouds
and Galactic halo.Comment: 29 pages, 6 figures. Complete Atlas of 94 additional images (~800kB
each) is available at http://fuse.pha.jhu.edu/~danforth/atlas Accepted to the
ApJS March 200
The prototype colliding-wind pinwheel WR 104
Results from the most extensive study of the time-evolving dust structure
around the prototype "Pinwheel" nebula WR 104 are presented. Encompassing 11
epochs in three near-infrared filter bandpasses, a homogeneous imaging data set
spanning more than 6 years (or 10 orbits) is presented. Data were obtained from
the highly successful Keck Aperture Masking Experiment, which can recover high
fidelity images at extremely high angular resolutions, revealing the geometry
of the plume with unprecedented precision. Inferred properties for the
(unresolved) underlying binary and wind system are orbital period 241.5 +/- 0.5
days and angular outflow velocity of 0.28 +/- 0.02 mas/day. An optically thin
cavity of angular size 13.3 +/- 1.4 mas was found to lie between the central
binary and the onset of the spiral dust plume. Rotational motion of the wind
system induced by the binary orbit is found to have important ramifications:
entanglement of the winds results in strong shock activity far downstream from
the nose of the bowshock. The far greater fraction of the winds participating
in the collision may play a key role in gas compression and the nucleation of
dust at large radii from the central binary and shock stagnation point.
Investigation of the effects of radiative braking pointed towards significant
modifications of the simple hydrostatic colliding wind geometry, extending the
relevance of this phenomena to wider binary systems than previously considered.
Limits placed on the maximum allowed orbital eccentricity of e < 0.06 argue
strongly for a prehistory of tidal circularization in this system. Finally we
discuss the implications of Earth's polar (i < 16 deg) vantage point onto a
system likely to host supernova explosions at future epochs.Comment: 35 pages, 8 figures, Accepted for publication in Astrophysical
Journa
A multi-stage genome-wide association study of bladder cancer identifies multiple susceptibility loci.
We conducted a multi-stage, genome-wide association study of bladder cancer with a primary scan of 591,637 SNPs in 3,532 affected individuals (cases) and 5,120 controls of European descent from five studies followed by a replication strategy, which included 8,382 cases and 48,275 controls from 16 studies. In a combined analysis, we identified three new regions associated with bladder cancer on chromosomes 22q13.1, 19q12 and 2q37.1: rs1014971, (P = 8 Ă 10â»ÂčÂČ) maps to a non-genic region of chromosome 22q13.1, rs8102137 (P = 2 Ă 10â»ÂčÂč) on 19q12 maps to CCNE1 and rs11892031 (P = 1 Ă 10â»â·) maps to the UGT1A cluster on 2q37.1. We confirmed four previously identified genome-wide associations on chromosomes 3q28, 4p16.3, 8q24.21 and 8q24.3, validated previous candidate associations for the GSTM1 deletion (P = 4 Ă 10â»ÂčÂč) and a tag SNP for NAT2 acetylation status (P = 4 Ă 10â»ÂčÂč), and found interactions with smoking in both regions. Our findings on common variants associated with bladder cancer risk should provide new insights into the mechanisms of carcinogenesis
The IDEAL study: investigation of dietary advice and lifestyle for women with borderline gestational diabetes: a randomised controlled trial - study protocol
BACKGROUND: The Australian Carbohydrate Intolerance Study in Pregnant Women (ACHOIS) showed that treatment of pregnant women with mild gestational diabetes mellitus is beneficial for both women and their infants. It is still uncertain whether there are benefits of similar treatment for women with borderline gestational diabetes. This trial aims to assess whether dietary and lifestyle advice and treatment given to pregnant women who screen for borderline gestational diabetes reduces neonatal complications and maternal morbidities. METHODS/DESIGN: Design: Multicentre, randomised controlled trial. Inclusion criteria: Women between 240 and 346 weeks gestation with a singleton pregnancy, a positive oral glucose challenge test (venous plasma glucose â„7.8 mmol/L) and a normal oral 75 gram glucose tolerance test (fasting venous plasma glucose <5.5 mmol/L and a 2 hour glucose <7.8 mmol/L) with written, informed consent. Trial entry and randomisation: Women with an abnormal oral glucose tolerance test (fasting venous plasma glucose â„5.5 mmol/L or 2 hour glucose â„7.8 mmol/L) will not be eligible and will be offered treatment for gestational diabetes, consistent with recommendations based on results of the ACHOIS trial. Eligible women will be randomised into either the âRoutine Care Groupâ or the âIntervention Groupâ. Study groups: Women in the âRoutine Care Groupâ will receive routine obstetric care reflecting current clinical practice in Australian hospitals. Women in the âIntervention Groupâ will receive obstetric care, which will include dietary and lifestyle advice, monitoring of blood glucose and further medical treatment for hyperglycaemia as appropriate. Primary study outcome: Incidence of large for gestational age infants. Sample size: A sample size of 682 women will be sufficient to show a 50% reduction in the risk of large for gestational age infants (alpha 0.05 two-tailed, 80% power, 4% loss to follow up) from 14% to 7% with dietary and lifestyle advice and treatment. DISCUSSION: A conclusive trial outcome will provide reliable evidence of relevance for the care of women with borderline glucose intolerance in pregnancy and their infants. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry - ACTRN12607000174482Caroline A. Crowther, William M. Hague, Philippa F. Middleton, Peter A. Baghurst, Andrew J. McPhee, Thac S. Tran, Lisa N. Yelland, Pat Ashwood, Shan Han, Jodie M. Dodd and Jeffrey S. Robinson for the IDEAL Study Grou
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