5,795 research outputs found
Risky Sexual Behaviour, Sexually Transmitted Infections, HIV/AIDS and Health Promotion among Students in the University of Douala
There are about 9,335 students in the University of Douala, 6,686 males and 3,832 females with a mean age of 20 years. Knowledge of the transmission of AIDS is high as indicated by 95% of the students, 80% were also able to identify preventive strategies. However, there is a failure to translate knowledge into protective action and behaviour. Between 1998 and 2001, there has been a nearly three-fold increase in cases of STIs from 137 to 360. Tuberculosis, which is strongly linked to HIV/AIDS in Douala, has also increased from 7 cases to 38. HIV/AIDS prevalence among students is estimated between 3%-5%. Both male and female students constitute a high-risk group because of multiple partners due to the adoption of several supposedly emotional/financial safe strategies. These include sponsors or male friends who pay rents, furnish rooms etc, in addition to campus girl friends/boy friends 'safety belts' and other short-term relationships. Condom usage is irregular. The University of Douala as part of its health promotion-prevention strategy has intensified its information, education and communication programme on HIV/AIDS with the support of governmental, non-governmental organisations and students clubs on campus and Peer educators have increased their sensitization activities. Preventive strategies include valorising positive cultural norms, empowering and encouraging students to practice sexual abstinence and fidelity. There is a need to incorporate students more in the design of appropriate and acceptable intervention strategies towards the prevention, health enhancement, treatment and management strategies of HIV/AIDS in the university arena
Heap Formation in Granular Media
Using molecular dynamics (MD) simulations, we find the formation of heaps in
a system of granular particles contained in a box with oscillating bottom and
fixed sidewalls. The simulation includes the effect of static friction, which
is found to be crucial in maintaining a stable heap. We also find another
mechanism for heap formation in systems under constant vertical shear. In both
systems, heaps are formed due to a net downward shear by the sidewalls. We
discuss the origin of net downward shear for the vibration induced heap.Comment: 11 pages, 4 figures available upon request, Plain TeX, HLRZ-101/9
Geographic Differences in Hospital Waiting Times
Access to elective surgery in Australian public hospitals is rationed using waiting lists. In this article, we undertake a DiNardo-Fortin-Lemieux reweighting approach to attribute variation in waiting time to clinical need or to discrimination. Using data from NSW public patients in 2004-2005, we find the discrimination effect dominates clinical need especially in the upper tail of the waiting time distribution. We find evidence of favourable treatment of patients who reside in remote areas and discrimination in favour of patients residing in particular Area Health Services. These findings have policy implications for the design of equitable quality targets for public hospitals. © 2012 The Economic Society of Australia
Shock volume: Patient-specific cumulative hypoperfusion predicts organ dysfunction in a prospective cohort of multiply injured patients
BACKGROUND:
Multiply injured patients are at risk of developing hemorrhagic shock and organ dysfunction. We determined how cumulative hypoperfusion predicted organ dysfunction by integrating serial Shock Index measurements.
METHODS:
In this study, we calculated shock volume (SHVL) which is a patient-specific index that quantifies cumulative hypoperfusion by integrating abnormally elevated Shock Index (heart rate/systolic blood pressure ≥ 0.9) values acutely after injury. Shock volume was calculated at three hours (3 hr), six hours (6 hr), and twenty-four hours (24 hr) after injury. Organ dysfunction was quantified using Marshall Organ Dysfunction Scores averaged from days 2 through 5 after injury (aMODSD2–D5). Logistic regression was used to determine correspondence of 3hrSHVL, 6hrSHVL, and 24hrSHVL to organ dysfunction. We compared correspondence of SHVL to organ dysfunction with traditional indices of shock including the initial base deficit (BD) and the lowest pH measurement made in the first 24 hr after injury (minimum pH).
RESULTS:
SHVL at all three time intervals demonstrated higher correspondence to organ dysfunction (R2 = 0.48 to 0.52) compared to initial BD (R2 = 0.32) and minimum pH (R2 = 0.32). Additionally, we compared predictive capabilities of SHVL, initial BD and minimum pH to identify patients at risk of developing high-magnitude organ dysfunction by constructing receiver operator characteristic curves. SHVL at six hours and 24 hours had higher area under the curve compared to initial BD and minimum pH.
CONCLUSION:
SHVL is a non-invasive metric that can predict anticipated organ dysfunction and identify patients at risk for high-magnitude organ dysfunction after injury.
LEVEL OF EVIDENCE:
Prognostic study, level III
Diagnostic and treatment dilemma of gingival enlargement: a report of 3 cases
Gingival enlargement is a common feature of periodontal disease which is occasionally associated with medication use for systemic conditions such as hypertension and epilepsy. However, other local and systemic factors have been implicated in the aetiopathogenesis of this condition which could pose diagnostic and therapeutic challenge for clinicians. This paper presents the management of three cases of gingival enlargement recently seen at the Dental Centre of the Lagos University Teaching Hospital, Lagos. The association of unusual secondary aetiological factors is emphasized
Pumping two dilute gas Bose-Einstein condensates with Raman light scattering
We propose an optical method for increasing the number of atoms in a pair of
dilute gas Bose-Einstein condensates. The method uses laser-driven Raman
transitions which scatter atoms between the condensate and non-condensate atom
fractions. For a range of condensate phase differences there is destructive
quantum interference of the amplitudes for scattering atoms out of the
condensates. Because the total atom scattering rate into the condensates is
unaffected the condensates grow. This mechanism is analogous to that
responsible for optical lasing without inversion. Growth using macroscopic
quantum interference may find application as a pump for an atom laser.Comment: 4 pages, no figure
Continuous Avalanche Segregation of Granular Mixtures in Thin Rotating Drums
We study segregation of granular mixtures in the continuous avalanche regime
(for frequencies above ~ 1 rpm) in thin rotating drums using a continuum theory
for surface flows of grains. The theory predicts profiles in agreement with
experiments only when we consider a flux dependent velocity of flowing grains.
We find the segregation of species of different size and surface properties,
with the smallest and roughest grains being found preferentially at the center
of the drum. For a wide difference between the species we find a complete
segregation in agreement with experiments. In addition, we predict a transition
to a smooth segregation regime - with an power-law decay of the concentrations
as a function of radial coordinate - as the size ratio between the grains is
decreased towards one.Comment: 4 pages, 4 figures, http://polymer.bu.edu/~hmaks
Angle of Repose and Angle of Marginal Stability: Molecular Dyanmics of Granular Particles
We present an implementation of realistic static friction in molecular
dynamics (MD) simulations of granular particles. In our model, to break
contacts between two particles, one has to apply a finite amount of force,
determined by the Coulomb criterion. Using a two dimensional model, we show
that piles generated by avalanches have a {\it finite} angle of repose
(finite slopes). Furthermore, these piles are stable under tilting
by an angle smaller than a non-zero tilting angle , showing that
is different from the angle of marginal stability ,
which is the maximum angle of stable piles. These measured angles are compared
to a theoretical approximation. We also measure by continuously
adding particles on the top of a stable pile.Comment: 14 pages, Plain Te
Stabilized high-power laser system for the gravitational wave detector advanced LIGO
An ultra-stable, high-power cw Nd:YAG laser system, developed for the ground-based gravitational wave detector Advanced LIGO (Laser Interferometer Gravitational-Wave Observatory), was comprehensively characterized. Laser power, frequency, beam pointing and beam quality were simultaneously stabilized using different active and passive schemes. The output beam, the performance of the stabilization, and the cross-coupling between different stabilization feedback control loops were characterized and found to fulfill most design requirements. The employed stabilization schemes and the achieved performance are of relevance to many high-precision optical experiments
Determining the Weak Phase From Charged Decays
A quadrangle relation is shown to be satisfied by the amplitudes for , and . By comparison with the
corresponding relation satisfied by decay amplitudes, it is shown that
the relative phases of all the amplitudes can be determined up to discrete
ambiguities. Making use of an SU(3) relation between amplitudes contributing to
the above decays and those contributing to , it is
then shown that one can determine the weak phase , where is the Cabibbo-Kobayashi-Maskawa
matrix describing the charge-changing weak interactions between the quarks
and .Comment: 16 pages, latex, 7 uuencoded figure
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