19,040 research outputs found
Alterations in Lipids and Adipocyte Hormones in Female-to-Male Transsexuals
Testosterone therapy in men and women results in decreased high-density lipoprotein cholesterol (HDL) and increased low-density lipoprotein cholesterol (LDL). We sought to determine whether testosterone therapy has this same effect on lipid parameters and adipocyte hormones in female-to-male (FTM) transsexuals. Twelve FTM transsexuals provided a fasting lipid profile including serum total cholesterol, HDL, LDL, and triglycerides prior to and after 1 year of testosterone therapy (testosterone enanthate or cypionate 50–125mg IM every two weeks). Subjects experienced a significant decrease in mean serum HDL (52 ± 11 to 40 ± 7mg/dL) (P < .001). The mean LDL (P = .316), triglyceride (P = .910), and total cholesterol (P = .769) levels remained unchanged. In a subset of subjects, we measured serum leptin levels which were reduced by 25% but did not reach statistical significance (P =.181) while resistin levels remained unchanged. We conclude that testosterone therapy in FTM transsexuals can promote an increased atherogenic lipid profile by lowering HDL and possibly reduce serum leptin levels. However, long-term studies are needed to determine whether decreases in HDL result in adverse cardiovascular outcomes.National Institutes of Health (M01RR000533
Surface Tension dominates Insect Flight on Fluid Interfaces
Flight on the two-dimensional air-water interface, with body weight supported
by surface tension, is a unique locomotion strategy well adapted for the
environmental niche on the surface of water. Although previously described in
phylogenetically basal aquatic insects like stone flies, the biomechanics of
interfacial flight has never been analyzed. Here, we report interfacial flight
as an adapted behaviour in water-lily beetles (Galerucella nymphaeae, Linnaeus
1758) which are also dexterous airborne fliers. We present the first
quantitative biomechanical model of interfacial flight in insects, uncovering
an intricate interplay of capillary, aerodynamic and neuromuscular forces. We
show that water-lily beetles use their tarsal claws to attach themselves to the
interface, via a fluid contact line pinned at the claw. We investigate the
kinematics of interfacial flight trajectories using high-speed imaging and
construct a mathematical model describing the flight dynamics. Our results show
that nonlinear surface tension forces make interfacial flight energetically
expensive compared to airborne flight at the relatively high speeds
characteristic of water-lily beetles, and cause chaotic dynamics to arise
naturally in these regimes. We identify the crucial roles of capillary-gravity
wave drag and oscillatory surface tension forces which dominate interfacial
flight, showing that the air-water interface presents a radically modified
force landscape for flapping wing flight compared to air.Comment: 7 figures, 4 supplementary figures, 12 videos (link given in
Supplementary Information
Pseudo-scalar Higgs Boson Production at Threshold NLO and NLL QCD
We present the first results on the production of pseudo-scalar through gluon
fusion at the LHC to NLO in QCD taking into account only soft gluon
effects. We have used the effective Lagrangian that describes the coupling of
pseudo-scalar with the gluons in the large top quark mass limit. We have used
recently available quantities namely the three loop pseudo-scalar form factor
and the third order universal soft function in QCD to achieve this. Along with
the fixed order results, we also present the process dependent resummation
coefficient for threshold resummation to NLL in QCD. Phenomenological
impact of these threshold NLO corrections to pseudo-scalar production at
the LHC is presented and their role to reduce the renormalisation scale
dependence is demonstrated.Comment: 34 pages, 17 figure
Unparticle physics in diphoton production at the CERN LHC
We have considered the di-photon production with unparticle at LHC. The
contributions of spin-0 and spin-2 unparticle to the di-photon production are
studied in the invariant mass and other kinematical distributions, along with
their dependencies on the model dependent parameters. The signal corresponding
to the unparticle is significant for moderate coupling constant values.Comment: 17 pages, 15 eps figure
Bumper catch of mackerel at Panjim, Goa
Mackeral fishery at Panjim during this season was exceptionally good ranging from 14 to 19 cm size. On an average each purse-seine landed a catch of about 3 tonnes of mackerel practically flooding the jetty. The prices crashed to Rs. 10/- per basket weighing 40 kg. Sixty seven purse-seiners , each one with 2 to 4 tonnes of mackerel landed on a single day and on next day 39 purse-seiners landed the catch at a rate of 1.5 to 5 tonnes by each boat
Chronic cough is associated with long breaks in esophageal peristaltic integrity on high-resolution manometry
An Impossibility Result for High Dimensional Supervised Learning
We study high-dimensional asymptotic performance limits of binary supervised
classification problems where the class conditional densities are Gaussian with
unknown means and covariances and the number of signal dimensions scales faster
than the number of labeled training samples. We show that the Bayes error,
namely the minimum attainable error probability with complete distributional
knowledge and equally likely classes, can be arbitrarily close to zero and yet
the limiting minimax error probability of every supervised learning algorithm
is no better than a random coin toss. In contrast to related studies where the
classification difficulty (Bayes error) is made to vanish, we hold it constant
when taking high-dimensional limits. In contrast to VC-dimension based minimax
lower bounds that consider the worst case error probability over all
distributions that have a fixed Bayes error, our worst case is over the family
of Gaussian distributions with constant Bayes error. We also show that a
nontrivial asymptotic minimax error probability can only be attained for
parametric subsets of zero measure (in a suitable measure space). These results
expose the fundamental importance of prior knowledge and suggest that unless we
impose strong structural constraints, such as sparsity, on the parametric
space, supervised learning may be ineffective in high dimensional small sample
settings.Comment: This paper was submitted to the IEEE Information Theory Workshop
(ITW) 2013 on April 23, 201
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