2,716 research outputs found
Enlargement of Cavernous Haemangioma Associated with Exogenous Administration of Oestrogens
A cavernous haemangioma of the liver which enlarged rapidly while the patient was receiving exogenous oestrogens is reported. A dramatic decrease in the size of the tumour was produced by ligating the right hepatic artery and portal vein. The literature on large haemangiomas of the liver is reviewed.S. Afr. Med. J., 48, 695 (1974)
Current challenges in the provision of ambulance services in New Zealand
Emergency Medical Services (EMS) in New Zealand has been serving the society since the first ambulance in 1892. Since then it has developed rapidly following national health system reforms and changes in lifestyle that increase demands and expectations from local communities. Today, the system provides high-quality pre-hospital emergency care. This article will briefly introduce some of the issues facing EMS that will impact the future of this crucial system in New Zealand. These issues include demands because of an aging population funding, double crewing, and volunteerism, registration, and unified standards
The FGK formalism for black p-branes in d dimensions
We present a generalization to an arbitrary number of spacetime (d) and
worldvolume (p+1) dimensions of the formalism proposed by Ferrara, Gibbons and
Kallosh to study black holes (p=0) in d=4 dimensions. We include the special
cases in which there can be dyonic and self- or anti-self-dual black branes.
Most of the results valid for 4-dimensional black holes (relations between
temperature, entropy and non-extremality parameter, and between entropy and
black-hole potential on the horizon) are straightforwardly generalized.
We apply the formalism to the case of black strings in N=2,d=5 supergravity
coupled to vector multiplets, in which the black-string potential can be
expressed in terms of the dual central charge and work out an explicit example
with one vector multiplet, determining supersymmetric and non-supersymmetric
attractors and constructing the non-extremal black-string solutions that
interpolate between them.Comment: 28 pages no figures; v2: some references adde
Numerical Study of the Two Color Attoworld
We consider QCD at very low temperatures and non-zero quark chemical
potential from lattice Monte Carlo simulations of the two-color theory in a
very small spatial volume (the attoscale). In this regime the quark number
rises in discrete levels in qualitative agreement with what is found
analytically at one loop on S3xS1 with radius R_S3 << 1/{\Lambda}_QCD. The
detailed level degeneracy, however, cannot be accounted for using weak coupling
arguments. At each rise in the quark number there is a corresponding spike in
the Polyakov line, also in agreement with the perturbative results. In addition
the quark number susceptibility shows a similar behaviour to the Polyakov line
and appears to be a good indicator of a confinement-deconfinement type of
transition.Comment: 18 pages, 10 figure
Computer-Generated Ovaries to Assist Follicle Counting Experiments
Precise estimation of the number of follicles in ovaries is of key importance in the field of reproductive biology, both from a developmental point of view, where follicle numbers are determined at specific time points, as well as from a therapeutic perspective, determining the adverse effects of environmental toxins and cancer chemotherapeutics on the reproductive system. The two main factors affecting follicle number estimates are the sampling method and the variation in follicle numbers within animals of the same strain, due to biological variability. This study aims at assessing the effect of these two factors, when estimating ovarian follicle numbers of neonatal mice. We developed computer algorithms, which generate models of neonatal mouse ovaries (simulated ovaries), with characteristics derived from experimental measurements already available in the published literature. The simulated ovaries are used to reproduce in-silico counting experiments based on unbiased stereological techniques; the proposed approach provides the necessary number of ovaries and sampling frequency to be used in the experiments given a specific biological variability and a desirable degree of accuracy. The simulated ovary is a novel, versatile tool which can be used in the planning phase of experiments to estimate the expected number of animals and workload, ensuring appropriate statistical power of the resulting measurements. Moreover, the idea of the simulated ovary can be applied to other organs made up of large numbers of individual functional units
Wilsonian Approach to Fluid/Gravity Duality
The problem of gravitational fluctuations confined inside a finite cutoff at
radius outside the horizon in a general class of black hole geometries
is considered. Consistent boundary conditions at both the cutoff surface and
the horizon are found and the resulting modes analyzed. For general cutoff
the dispersion relation is shown at long wavelengths to be that of a
linearized Navier-Stokes fluid living on the cutoff surface. A cutoff-dependent
line-integral formula for the diffusion constant is derived. The
dependence on is interpreted as renormalization group (RG) flow in the
fluid. Taking the cutoff to infinity in an asymptotically AdS context, the
formula for reproduces as a special case well-known results derived
using AdS/CFT. Taking the cutoff to the horizon, the effective speed of sound
goes to infinity, the fluid becomes incompressible and the Navier-Stokes
dispersion relation becomes exact. The resulting universal formula for the
diffusion constant reproduces old results from the membrane
paradigm. Hence the old membrane paradigm results and new AdS/CFT results are
related by RG flow. RG flow-invariance of the viscosity to entropy ratio is shown to follow from the first law of thermodynamics together with
isentropy of radial evolution in classical gravity. The ratio is expected to
run when quantum gravitational corrections are included.Comment: 34 pages, harvmac, clarified boundary conditio
Magnetic resonance imaging of uterine fibroids: a preliminary investigation into the usefulness of 3D-rendered images for surgical planning
Electromyographic Analysis of the Shoulder Girdle Musculature during External Rotation Exercises
Background: Implementation of overhead activity, a key component of many professional sports, requires an effective and balanced activation of shoulder girdle muscles particularly during forceful external rotation motions.
Purpose: The study aimed to identify activation strategies of 16 shoulder girdle muscles/muscle segments during common shoulder external rotational exercises.
Study Design: Cross-Sectional Study
Method: EMG was recorded in 30 healthy subjects from 16 shoulder girdle muscles/muscle segments (surface electrode: anterior, middle and posterior deltoid, upper, middle and lower trapezius, serratus anterior, teres major, upper and lower latissimus dorsi, upper and lower pectoralis major; fine wire electrodes: supraspinatus, infraspinatus, subscapularis and rhomboid major) using a telemetric EMG system. Five external rotation (ER) exercises (standing ER at 0o and 90o of abduction, and with under-arm towel roll, prone ER at 90o of abduction, side-lying ER with under-arm towel) were studied. Exercise EMG amplitudes were normalised to EMGmax (EMG at maximal ER force in a standard position). Univariate analysis of variance (ANOVA) and post-hoc analysis applied on EMG activity of each muscle to assess the main effect of exercise condition.
Results: Muscular activity differed significantly among the ER exercises (P<0.05 – P<0.001). The highest activation for anterior and middle deltoid, supraspinatus, upper trapezius, and serratus anterior occurred during standing ER at 90o of abduction; for posterior deltoid, middle trapezius, and rhomboid during side-lying ER at 0° of abduction; for lower trapezius, upper and lower latissimus dorsi, subscapularis, and teres major during prone ER at 90o of abduction, and for clavicular and sternal part of pectoralis major during standing ER with Under-Arm Towel.
Conclusion: Key glenohumeral and scapular muscles can be optimally activated during the specific ER exercises particularly in positions that stimulate athletic overhead motions.
Clinical Relevance: These results enable sport medicine professionals to target specific muscles during shoulder rehabilitation protocols while minimising the effect of others, providing a foundation for optimal evidence-based exercise prescription. They also provide information for tailored muscle training and injury prevention in overhead sports
QCD with Chemical Potential in a Small Hyperspherical Box
To leading order in perturbation theory, we solve QCD, defined on a small
three sphere in the large N and Nf limit, at finite chemical potential and map
out the phase diagram in the (mu,T) plane. The action of QCD is complex in the
presence of a non-zero quark chemical potential which results in the sign
problem for lattice simulations. In the large N theory, which at low
temperatures becomes a conventional unitary matrix model with a complex action,
we find that the dominant contribution to the functional integral comes from
complexified gauge field configurations. For this reason the eigenvalues of the
Polyakov line lie off the unit circle on a contour in the complex plane. We
find at low temperatures that as mu passes one of the quark energy levels there
is a third-order Gross-Witten transition from a confined to a deconfined phase
and back again giving rise to a rich phase structure. We compare a range of
physical observables in the large N theory to those calculated numerically in
the theory with N=3. In the latter case there are no genuine phase transitions
in a finite volume but nevertheless the observables are remarkably similar to
the large N theory.Comment: 44 pages, 18 figures, jhep3 format. Small corrections and
clarifications added in v3. Conclusions cleaned up. Published versio
Supersymmetric Charged Clouds in AdS_5
We consider supersymmetric holographic flows that involve background gauge
fields dual to chemical potentials in the boundary field theory. We use a
consistent truncation of gauged N=8 supergravity in five dimensions and we give
a complete analysis of the supersymmetry conditions for a large family of
flows. We examine how the well-known supersymmetric flow between two fixed
points is modified by the presence of the chemical potentials and this yields a
new, completely smooth, solution that interpolates between two global AdS
spaces of different radii and with different values of the chemical potential.
We also examine some black-hole-like singular flows and a new
non-supersymmetric black hole solution. We comment on the interpretation of our
new solutions in terms of giant gravitons and discuss the implications of our
work for finding black-hole solutions in AdS geometries.Comment: 31 pages, 6 figures; minor corrections, updated reference
- …