Isoparametric and Dupin Hypersurfaces

A hypersurface $M^{n-1}$ in a real space-form ${\bf R}^n$, $S^n$ or $H^n$ is isoparametric if it has constant principal curvatures. For ${\bf R}^n$ and $H^n$, the classification of isoparametric hypersurfaces is complete and relatively simple, but as Elie Cartan showed in a series of four papers in 1938-1940, the subject is much deeper and more complex for hypersurfaces in the sphere $S^n$. A hypersurface $M^{n-1}$ in a real space-form is proper Dupin if the number $g$ of distinct principal curvatures is constant on $M^{n-1}$, and each principal curvature function is constant along each leaf of its corresponding principal foliation. This is an important generalization of the isoparametric property that has its roots in nineteenth century differential geometry and has been studied effectively in the context of Lie sphere geometry. This paper is a survey of the known results in these fields with emphasis on results that have been obtained in more recent years and discussion of important open problems in the field.Comment: This is a contribution to the Special Issue "Elie Cartan and Differential Geometry", published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGM

Declining Visceral Leishmaniasis in Malta

Aims: To study visceral leishmaniasis (VL) trends in Malta. Methods: Analysis of epidemiological and clinical trends, a veterinary questionnaire and questioning a canine laboratory testing facility. Results: A decline in VL in the past 25 years (1980-2005) was noted for both paediatric (p<0.001) and adult (p=0.002) populations. No seasonal variation in infection rates was found. Serological testing was reliable and a useful adjunct to bone marrow diagnosis. Treatment with sodium stibogluconate was highly effective and there were no permanent sequelae associated with disease or treatment. Vets are encountering less canine VL with no differences in localities Discussion: The decline in VL was paralleled by a decline in the stray canine reservoir population and by better management of canine infection in both sanctuaries and in domestic settings.peer-reviewe

Nitrogen metabolism of the isolated tissues of the rat

Little study has been devoted to the anabolic aspects of nitrogen metabolism in animals. The reason, of course, has been the difficulty of obtaining experimental conditions in which these can be observed, measured, and analyzed. The experiments of Krebs and Henseleit (1) on the formation of urea from ammonia with Warburg’s method of surviving slices of liver suggested that this method might be useful in a direct attack on a number of problems of nitrogen anabolism in animals; i.e., it might be possible to observe reactions in which there is a gain in free energy. It appears that for these reactions the intact cell structure is necessary

A resistant case of Kawasaki Disease

Kawasaki disease (KD) is an acute febrile illness of childhood of unknown origin which may cause coronary arteritis and death. The Maltese incidence has been calculated at 3.2/100,000 population 4 years of age, similar to that reported in European communities and far lower than that reported in Asian countries. The use of steroids in this condition remains contentious. We report a resistant case of KD who required two doses of pulsed steroids in addition to standard treatment with aspirin and immunoglobulin.peer-reviewe

Prevalence of Infantile Hypertrophic Pyloric Stenosis and relation to breast feeding trends in the Maltese Islands between 1995 and 2007

Introduction: Several studies have indicated that breastfeeding may protect against the development of infantile hypertrophic pyloric stenosis (IHPS). This study investigated trends in IHPS over the period 1995-2007 in Malta and analysed the relationship of IHPS and changes in infant feeding practices during the same time period. Methods: Patients with IHPS were identified from Hospital Activity Analysis reports. The case notes were obtained and the following data were collected: birth order of the patient, gender and type of feeding. Breast feeding information trends were obtained from published reports. Population data were obtained from publications of the National Statistics Office. Results: A total of 125 patients were operated for IHPS. Case records were available for 86. The incidence was 2.26 per 1000 live births. There was an expected preponderance of males with no mortality. Seventy one patients (82.5%) had been formula fed from day one, while ten patients were exclusively breast fed. Five patients were breast fed and supplemented with formula at presentation. Forty-six patients were first born infants. A nonsignificant downward trend was noted. IHPS was significantly less common in breast fed infants (χ2 72.4, p=<0.001). Conclusion: These findings further support the hypothesis that breast feeding protects against the development of IHPS.peer-reviewe

Assessing Causation in Breast Implant Litigation: The Role of Science Panels

In two recent cases, federal judges appointed panels of scientific experts to help assess conflicting scientific testimony regarding causation of systemic injuries by silicone gel breast implants. This article will describe the circumstances that gave rise to the appointments, the procedures followed in making the appointments and reporting to the courts, and the reactions of the participants in the proceedings

Initial Validation of a Brief Pictorial Measure of Caregiver Aggression: The Family Aggression Screening Tool

In the present study, we report on the development and initial psychometric properties of the Family Aggression Screening Tool (FAST). The FAST is a brief, self-report tool that makes use of pictorial representations to assess experiences of caregiver aggression, including direct victimization and exposure to intimate partner violence. It is freely available on request and takes under 5 minutes to complete. Psychometric properties of the FAST were investigated in a sample of 168 high-risk youth aged 16 to 24 years. For validation purposes, maltreatment history was assessed using the Childhood Trauma Questionnaire; levels of current psychiatric symptoms were also assessed. Internal consistency of the FAST was good. Convergent validity was supported by strong and discriminative associations with corresponding Childhood Trauma Questionnaire subscales. The FAST also correlated significantly with multi-informant reports of psychiatric symptomatology. Initial findings provide support for the reliability and validity of the FAST as a brief, pictorial screening tool of caregiver aggression