Effect of Anodic Oxidation on the Characteristics of Lattice-Matched AlInN/GaN Heterostructures

The effect of anodic oxidation on the electronic characteristics of lattice-matched AlInN/GaN heterostructures was investigated using field-effect transistor (FET) structures with the gate areas in direct contact with the electrolytes. The gate surface of the FETs was subjected to anodic oxidation in 0.1 M KOH. The oxidized heterostructures were analyzed by electrochemical impedance spectroscopy and by modeling the characteristics of the electrolyte-gate FETs and the energy-band diagram of the heterostructures. This analysis suggested that the anodic treatment induced a bulk oxidation of the AlInN barrier. The Fermi level at the oxidized AlInN surface was shifted deep into the bandgap. The oxidation led to a reduction of the carrier mobility and to partial depletion of the channel.     

Control of polarization switching in vertical coupled-cavities surface emitting lasers

We report a novel three-contact vertical-cavity surface-emitting laser (VCSEL) for use in polarization-sensitive optical applications. The device consists of two vertical cavities, coupled by a common mirror. We demonstrate that one can independently choose both the power of the output beam-through the current in the first cavity-and the polarization state-through the bias applied to the second cavity. The control of the polarization state is performed with a control voltage in the range -2 to 0 V. Within this interval, the structure exhibits a bistable behavior. We present the very first experimental proof of nonthermal, electrically induced polarization switching in coupled-cavities VCSELs.     

Nuclear fusion between heavy ions by the gamma-ray spectroscopy method

The in-beam and off-beam gamma-ray spectroscopy method, as a tool for the study of nuclear fusion between heavy ions, is described. These methods allow the study of the production and decay of the compound nucleus, inelastic scattering and transfer reactions. In this work we report the determination of fusion cross sections at energies near and below the Coulomb barrier for a series of systems: targets of ^46,50Ti, ⁵⁹Co and ^64,66Zn bombarded by ¹⁴N and ¹⁶O projectiles. Cross sections from 0.4 to 1000 mb were measured.     

Gas enema for the reduction of intussusception: relationship between clinical signs and symptoms and outcome

OBJECTIVE: The aim of this study was to establish the extent to which the clinical features of intussusception can be used to predict successful outcome of gas enema and to determine whether the nonsurgical management of intussusception in children can be improved by refining the criteria used to select patients for gas enema. SUBJECTS AND METHODS: Clinical data on 282 consecutive episodes of intussusception (255 patients) were collected prospectively from January 1987 to July 1991. Gas enema was performed in 273 episodes, in which the clinical signs and symptoms were studied by using logistic regression. Nine patients had primary surgery. RESULTS: Gas enema was successful in 216 (79%) of 273 enemas attempted. Fifty-seven patients had surgery after unsuccessful enema. Univariate analysis showed significant associations between successful enema and duration of signs and symptoms less than 12 hr, no rectal bleeding, absence of small-bowel obstruction, presence of a palpable mass, and normal hydration. Multivariate analysis showed that dehydration, small-bowel obstruction, and duration of signs and symptoms longer than 12 hr were significant predictors of unsuccessful enema; yet, in these groups the rate of success still justified attempted enema. Even in severe dehydration, the successful enema reduction rate was 31%. CONCLUSION: Our data suggest that although the factors identified had some predictive value in determining the outcome of attempted enema reduction, they could not be used to indicate patients in whom enema reduction should not be attempted. All patients with intussusception should have a gas enema if the absolute contraindications to enema (i.e., peritonitis or perforation) are absent.     

Determinants of fibrinogen in an Italian population suffering from claudication. Lower fibrinogen in the south compared to middle and north of Italy. The ADEP Group

In Switzerland the longitudinal SENECA study (Survey in Europe on Nutrition and the Elderly, a Concerted Action of the 3rd European Framework Programme) was implemented in the city of Yverdon-les-Bains. The study investigated the nutritional and health status of 70 to 75-year old elderly living at home, in relation with their food habits, life style, social network and physical activity with a follow-up study 4 years later. Results of the follow-up study, with the subjects aged 74 to 79 years, and changes observed over the 4 years are presented here. The participants reported a rather good self-assessed health and were quite independent in their daily activities. Food and nutrient intakes decreased over the 4-year follow-up, as did physical activity, independence in daily activities and height. However, biological markers (haemoglobin, haematocrit, albumin, lipids and vitamins) of nutritional status showed little change and remained mostly in the normal range. Low energy intake was measured in 21% of the men (< 1500 kcal/d) and in 24% of the women (< 1200 kcal). This is a source of concern since such low energy intakes make it difficult to cover micronutrient requirements. It is therefore important to find ways to maintain or increase the quality of the diet and adequate nutrient intakes.     

Steam (physical) refining deodorizer for malaysian palm oil

The production of Malaysian palm oil is expected to increase 20% per year for the next 5 yr. Already planted are more than a million acres which will start to produce in the next few years. Recent plantings of new strains will produce 2400 to 3000 lb of palm oil per acre. Palmex Industries, Penang, Malaysia started in operation in August, 1975, a physical refining system to produce a deodorized palm oil with 0.03% free fatty acid (FFA) from crude palm oil containing 5.0% FFA. Production records confirm the feasibility of physical refining crude palm oil in Malaysia, ex-porting the oil to the United States, and producing a quality product with a minimum of additional pro-cessing.