Optimal test planning for the fatigue-limit model when the fatigue-limit distribution is known

This article discusses tools for planning life tests under the random fatigue-limit model, when the form of the fatigue-limit distribution is completely specified. Expressions for the Fisher information matrix elements are provided. Test-plan objectives, such as minimum variance of quantile or parameter estimator, can be written in terms of these expressions. Under Type I censoring, all experimental conditions can be described by a standardized slope parameter & a standardized log(censoring time). This article provides equivalence theorems, which can be used to check the optimality of test plans which often have two levels. The best three-level standard test plans are not optimal, but, in general, involve fewer extrapolations to low stresses than the optimal plans. Test plans for a titanium-alloy fatigue test are presented to illustrate the methods.     

Spanish study of quality of life in migraine (I). Profile of the patient with migraine attending neurology clinics

This study reports our experience with 67 intrauterine transfusions (IUTs) carried out for 27 cases of severe Rh alloimmunization, which could be useful to other developing countries with similar situations. Most of the mothers were from sections of India other than Mumbai, their socioeconomic status was low, and they were referred during the second or third trimester. The mean gestation age at first IUT was 27+/-2.9 weeks and maternal anti-D titer ranged from 1:32 to 1:512. Ultrasonography (USG) was normal in eight cases, but showed minimal or gross ascites in 8 and 11 cases, respectively. The mean +/- SD hematocrit (HCT) in three groups defined by USG was 23.5+/-1.7, 15.9+/-4, and 12+/-5.9, respectively. Amniotic fluid analysis, which proved to be an important investigation, indicated IUT in eight cases having normal USG. Six cases were severely anemic (Hb deficit >7 g/dl). By fetal cell staining, the percentage of the donor's red cells in the fetal circulation was determined. Besides Hb, blood group, direct antiglobulin test, and mean cell volume, this parameter was also useful in assessing efficacy of IUT and the need for an exchange transfusion after birth. Of 11 fetuses having gross ascites, eight and one each from the remaining two groups, were stillborn. One death may be procedure related. Two neonates died due to hemorrhagic disorder and prematurity. The overall survival rate was 55.6%. Late referral, severe Rh alloimmunization, volume overload, delay in IUT because of nonavailability of blood and use of nonirradiated blood could be the reasons for the poor outcome. Strategies for improving results are discussed.     

Usefulness of anti-neutrophil cytoplasmic antibodies, anti-proteinase 3 and anti-myeloperoxidase in management of small vessel vasculitis

BACKGROUND: Analysis of usefulness of antineutrophil cytoplasmic antibodies (AN-CA) as a marker of clinical activity in small vessel vasculitis. PATIENTS AND METHODS: 33 patients, 10 patients with Wegener's granulomatosis (WG) and 23 with microscopic polyangiitis (MPA) and rapidly progressive glomerulonephritis type III (RPGN III). The clinic and serologic follow-up was accomplished every 3 months during an average of 19 (SD, 24) months (range 3-52 months. The serologic follow-up included the determination of ANCA by indirect immunofluorescence (IFI) and ELISA, as well as the serum level of C reactive protein (RCP). RESULTS: At the time of diagnosis all patients were ANCA positive by IFI and ELISA. The seroconversion of ANCA from positive to negative was produced in 30/33 patients (90%). Twenty-six out of these 30 patients (87%) achieved the seroconversion within the first 6 months. During the follow-up 4 patients had a major relapse, all with positive ANCA. In 2 patients, one of each group, seroconversion from negative to positive was not associated with clinical relapse of vasculitis. CONCLUSION: ANCA should be used in conjunction with other indices of disease activity in patients with small vessel vasculitis.     

Beneficial Effects of Metformin on the Central Nervous System,with a Focus on Epilepsy and Lafora Disease

Metformin is a drug in the family of biguanide compounds that is widely used in the treatment of type 2 diabetes (T2D). Interestingly, the therapeutic potential of metformin expands its prescribed use as an anti-diabetic drug. In this sense, it has been described that metformin administration has beneficial effects on different neurological conditions. In this work, we review the beneficial effects of this drug as a neuroprotective agent in different neurological diseases, with a special focus on epileptic disorders and Lafora disease, a particular type of progressive myoclonus epilepsy. In addition, we review the different proposed mechanisms of action of metformin to understand its function at the neurological level.     

The use of blast furnace slag and derived materials in the vitrification of electric arc furnace dust

The electric arc furnace (EAF) dust was added to blast furnace granulated slag or a gel produced by dissolving slag in HNO₃/EtOH followed by alkaline hydrolysis and gelification, and then it was vitrified. The proportion of EAF dust used was between 5 and 30 wt pct. The physicochemical properties of the glasses produced were studied by the X-ray powder diffraction technique, differential thermal analysis, and transmission electron microscopy (TEM). Thermal properties (dilatometric softening point, glass transition temperature, and thermal expansion coefficient) were determined. Finally, analyses were performed on leachability and ecotoxicity. The results suggest that the use of either slag or slag-derived gel produces a borosilicate glass with thermal properties similar to those of conventional soda-lime-silicate glass.     

Pneumocephalus after shunting for hydrocephalus

A case of tension pneumocephalus that occurred after ventriculoperitoneal shunting is presented. We have reviewed 12 cases of pneumocephalus in association with ventriculoperitoneal shunt placement. This phenomenon occurs when air is forced through the shunt or enters through the cranial base because of: iatrogenic postsurgical connection, congenital fistula, trauma, or thinning of the cranial base. Ways of preventing and treating this problem are outlined.     

Bimanual mirror letter writing: a post-traumatic case

Mirror writing is inverse writing that can only be read with the help of a mirror. It is generally associated with dominant hemisphere lesions and affects only one hand. We describe the case of a patient who, after cranial injury, developed bimanual mirror writing for letters but no other focal neurological symptom. The only abnormal complementary finding was a zone of left parieto-occipital hypoperfusion visibly by SPECT. No signs of psychological disorder were present to which the dysgraphia could be attributed. Symptoms disappeared after three months. We conclude that isolated bimanual mirror letter writing may be an expression of reversible parieto-occipital dysfunction of the dominant hemisphere.