The temperature dependence of the F band in magnesium oxide

The position and width of the F band in magnesium oxide have been measured in the temperature range 4-400 °K. The data have been analysed in terms of the simplest adequate `configuration coordinate' model. The width results give an effective frequency of 7.8 × 10^12 s^-1, which is close to a peak in the phonon density of states and to the value extrapolated from data for the alkali halides. There is evidence that the effective frequency is reduced by about 5% in the excited state of the F centre. The Huang-Rhys factor is about 39, and luminescence is predicted at about 2.4 eV. The band shape indicates the existence of three small absorption bands on the high-energy side of the main F absorption band. These appear to be associated with the F centre, but their nature is not clear

'The world is full of big bad wolves': investigating the experimental therapeutic spaces of R.D. Laing and Aaron Esterson

In conjunction with the recent critical assessments of the life and work of R.D. Laing, this paper seeks to demonstrate what is revealed when Laing’s work on families and created spaces of mental health care are examined through a geographical lens. The paper begins with an exploration of Laing’s time at the Tavistock Clinic in London during the 1960s, and of the co-authored text with Aaron Esterson entitled, Sanity, Madness and the Family (1964). The study then seeks to demonstrate the importance Laing and his colleague placed on the time-space situatedness of patients and their worlds. Finally, an account is provided of Laing’s and Esterson’s spatial thinking in relation to their creation of both real and imagined spaces of therapeutic care

Equitable allocation of extrarenal organs: With special reference to the liver

A national plan is proposed for the equitable allocation of extrarenal organs, with particular reference to the liver. The principles of the plan include preferential use of the organs in the local and regional area of procurement, with national listing of the organs left over after the original cut. At each of the local, regional, and national levels, the allocation is based on total points awarded for medical urgency, time waiting, blood group conformity, and physical location of both donor and recipient. The plan, which should be applicable as well for allocation of hearts, is compatible with international sharing with nearby countries such as Canada

Substance use disorders in adolescents with attention deficit hyperactivity disorder: a 4-year follow-up study

Aim To examine the relationship between a childhood diagnosis of attention deficit hyperactivity disorder (ADHD) with or without oppositional defiant disorder (ODD)/conduct disorder (CD) and the development of later alcohol/drug use disorder [psychoactive substance use disorder (PSUD)] and nicotine dependence in a large European sample of ADHD probands, their siblings and healthy control subjects. Participants design and settingSubjects (n=1017) were participants in the Belgian, Dutch and German part of the International Multicenter ADHD Genetics (IMAGE) study. IMAGE families were identified through ADHD probands aged 5-17 years attending out-patient clinics, and control subjects from the same geographic areas. After a follow-up period (mean: 4.4 years) this subsample was re-assessed at a mean age of 16.4 years. Measurements PSUD and nicotine dependence were assessed using the Diagnostic Interview Schedule for Children, Alcohol Use Disorders Identification Test, Drug Abuse Screening Test and Fagerstrom test for Nicotine Dependence. Findings The ADHD sample was at higher risk of developing PSUD [hazard ratio (HR)=1.77, 95% confidence interval (CI)=1.05-3.00] and nicotine dependence (HR=8.61, 95% CI=2.44-30.34) than healthy controls. The rates of these disorders were highest for ADHD youth who also had CD, but could not be accounted for by this comorbidity. We did not find an increased risk of developing PSUD (HR=1.18, 95% CI=0.62-2.27) or nicotine dependence (HR=1.89, 95% CI=0.46-7.77) among unaffected siblings of ADHD youth. Conclusions A childhood diagnosis of attention deficit hyperactivity disorder is a risk factor for psychoactive substance use disorder and nicotine dependence in adolescence and comorbid conduct disorder, but not oppositional defiant disorder, further increases the risk of developing psychoactive substance use disorder and nicotine dependence

Outcomes of positive airway pressure for sleep apnea-reply

Abstract not availableR. McEvoy, Z. Zhou, B. Nea

Incidence and risk factors for retinal vein occlusion at the University of Port Harcourt Teaching Hospital, Port Harcourt, Nigeria

Objective: The objective of the following study is to determine the  incidence of retinal vein occlusion (RVO) and identify the risk factors in RVO in patients presenting to a tertiary hospital in Rivers State.Materials and Methods: The medical records of consecutive patients with RVO who presented to the retina clinic of the eye Department of University of Port Harcourt Teaching Hospital over a 5 year period were retrieved. Information extracted from the data included the demographic data of patients, presenting visual acuity, history of systemic and ocular disease, blood pressure and intraocular pressure. Data was analyzed using the Statistical Package for Social Sciences 20.0. (IBM Corporation and its licensors 1989,2011).Results: Out of the 364 patients seen at the retina clinic during this period, 27 (7.4%) had RVO. Seven patients had bilateral disease. The incidence of RVO in the retinal clinic was 7.4%. Systemic hypertension, diabetes   mellitus, hyperlipidemia and glaucoma were the main risk factors recorded in our patients. Central retinal vein occlusion (CRVO) 20 (74%) was morepredominant than branch retinal vein occlusion (BRVO) 7 (26%). 21 eyes of patients with CRVO had visual acuities of < 3/60, while 7 eyes of patients with BRVO had visual acuities less than 3/60. Vitreous hemorrhage 10 (52.6%) was the most common complication encountered. All cases of non.perfused vein occlusion 4 (14.8%) were seen in patients who had CRVO.Conclusion: The incidence of RV in our hospital is high. RVO is a significant cause of visual impairment, with CRVO being more common. Identifying associated risk factors and treating these could help reduce the incidence of RVO.Key words: Incidence, Port Harcourt, retinal vein occlusion, risk factor

Cadaveric renal transplantation at the University of Pittsburgh: a two and one-half-year experience with the point system.

From January 1, 1986 to July 30, 1988, 530 consecutive cadaver kidney transplantations were performed with patient selection by a point system that took into account time awaiting an organ, donor-recipient matching, degree of presensitization, and some less important factors. The effect of the system was to diminish judgmental factors in case selection which in the past, had probably operated to the disadvantage of "undesirable" potential recipients, including older ones. Primary 1-year graft survival (74%) and graft survival after retransplantation (71%) were lower than in the earlier time. However, the results with triple-drug therapy using CsA, AZA and P demonstrated 88% 1-year graft survival for primary graft recipients and 74% in highly sensitized patients, with comparable patient mortality. These latter observations provide some assurance that the concepts of equitable access and efficient utilization of a scarce resource are not mutually exclusive

Position and structure of the subtropical/Azores front region from combined Lagrangian and remote sensing (IR/altimeter/SeaWIFS) measurements

The position and structure of the North Atlantic Subtropical Front is studied using Lagrangian flow tracks and remote sensing (AVHRR imagery: TOPEX/POSEIDON altimetry: SeaWiFS) in a broad region ( similar to 31 degree to similar to 36 degree N) of marked gradient of dynamic height (Azores Current) that extends from the Mid-Atlantic Ridge (MAR), near similar to 40 degree W, to the Eastern Boundary ( similar to 10 degree W). Drogued Argos buoy and ALACE tracks are superposed on infrared satellite images in the Subtropical Front region. Cold (cyclonic) structures, called storms, and warm (anticyclonic) structures of 100-300 km in size can be found on the south side of the Subtropical Front outcrop, which has a temperature contrast of about 1 degree C that can be followed for similar to 2500 km near 35 degree N. Warmer water adjacent to the outcrop is flowing eastward (Azores Current) but some warm water is returned westward about 300 km to the south (southern Counterflow). Estimates of horizontal diffusion in a Storm (D=2.2t10 super(2) m super(2) s super(-1)) and in the Subtropical Front region near 200 m depth (D sub(x)=1.3t10 super(4) m super(2) s super(-1), D sub(y)=2.6t10 super(3) m super(2) s super(-1)) are made from the Lagrangian tracks. Altimeter and in situ measurements show that Storms track westwards. Storms are separated by about 510 km and move westward at 2.7 km d super(-1). Remote sensing reveals that some initial structures start evolving as far east as 23 degree W but are more organized near 29 degree W and therefore Storms are about 1 year old when they reach the MAR (having travelled a distance of 1000 km). Structure and seasonality in SeaWiFS data in the region is examined