The effect of photo-oxidation on thermal and fire retardancy of polypropylene nanocomposites

Nanocomposites of polypropylene-graft-maleic anhydride/clay were prepared by melt blending in an extruder mixer. The nanoscale dispersion of the clay in the polymer was analysed by wide-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results of XRD and TEM showed that the nanocomposites obtained were a kind of intercalated-delaminated structures side by side with different dominant states, depending on the clay used and on the processing conditions. The consequences of photo-oxidation on the thermal stability and fire retardant properties of the nanocomposites were investigated using thermogravimetric analysis and cone calorimetry tests. It appeared that this degradation dramatically affected the important properties of the nanocomposites. A loss of thermal stability and fire retardant performance was observed. This was ascribed to scission reactions that occurred during the oxidative degradation prior to thermal and fire tests.     

Malaria in the southern sanitary district of Dakar (Senegal). 2. Entomologic data]

This study aimed to investigate the cause of persistently increased serum gastrin concentration seen in some Graves' disease patients even when euthyroid during antithyroid drug treatment. The subjects studied consisted of three groups: 33 patients with a common-type of Graves' disease, 14 with triiodothyronine (T3)-predominant Graves' disease (characterized from previous studies as having potent immunologic abnormalities including greater concentrations of thyroid-stimulating antibodies together with larger goiter size), and a group of 20 normal subjects. Fasting serum gastrin concentrations in common Graves' disease patients were significantly higher than those of normal subjects (58.4 +/- 38.9 pmol/L vs. 37.8 +/- 18.9 pmol/L [mean +/- SD], p < 0.05). The serum gastrin concentrations were even greater in T3-predominant Graves' disease patients than common Graves' disease patients (162.9 +/- 224.0 pmol/L vs. 58.4 +/- 38.9 pmol/L, p < .05). Serum pepsinogen I (PGI) concentrations were significantly lower in the T3-predominant patient group than the common Graves' group (24.0 +/- 12.9 ng/mL vs. 39.7 +/- 19.6 ng/mL, p < .05). Serum ratios of PG I to PG II were significantly lower in the T3-predominant Graves' disease patients than normal subjects (3.59 +/- 2.66 vs. 5.97 +/- 1.56, p < .01). The ratios also had a significant (p < .05) inverse correlation with serum gastrin concentrations in T3-predominant Graves' disease patients. The results suggest that autoimmune gastritis is associated with Graves' disease, particularly in patients with potent thyroid-autoimmunity.     

Dietary intake of Senegalese adults

The aim of this work is to identify major food sources and dietary constituents of Senegalese adults. We conducted a cross-sectional study, using a single 24-hour dietary recall interview. Foods were classified into food groups based on similarities in nutrient content or use. Food groups included foods consumed individually, or as part of food mixtures such as stews, soups, or sandwiches. Median consumption (amount/day) of each food was determined and examined by relevant subgroups. Participants were 50 healthy Senegalese men, aged 20-62 years recruited at the Hôpital Général de Grand Yoff in Dakar, Senegal and from Sendou village, a rural area outside Dakar. A total of 90 foods and beverages were identified and classified into 11 groups. Sixty-five percent of foods identified could be classified as meats, grains, or fruits/vegetables. Fruits and vegetables comprised 42% (38/90) of all foods; meats 12% (11/90); and grains 11% (10/90). Sauces (6%, 5/90), sweets (4%, 4/90), and desserts (4%, 4/90) were also reported. The most common fruits/vegetables reported were potato, carrot, mango, and lettuce; commonly reported grains were bread and rice; and commonly reported meats were fish, beef, and ox. There were no differences in reported daily intake of each food by age, ethnicity, education, or residence. Most foods reported were traditional to the Senegalese diet, despite the increasing availability of Western foods in Senegal.     

Modeling of Step Voltage Regulators in Multiphase Load Flow Solution of Distribution Systems Using Newton's Method and Augmented Nodal Analysis

The increasing complexity of distribution systems requires general, efficient, and large-scale capable methods. This paper proposes a new technique to find the tap positions of step voltage regulators in multiphase load flow solvers in a direct and efficient manner. This is achieved by applying Newton method to the system of equations obtained by using the concept of augmented matrix formulation and adding the constraint equations. This approach allows employing the regulator equations directly. The regulators are modeled by taking into account the line drop compensator circuit with its settings, i.e., the desired voltage level, bandwidth, and R′ and X′ settings, which represent the scaled impedance parameters of the distribution feeder between the regulator and the load center at which the voltage is controlled. The limits of the regulators such as minimum and maximum tap positions are also accounted for. The proposed technique represents a voltage regulator with transformer equations using an augmented matrix formulation. The mismatch equations are developed using the desired voltage setting in constraint equations with transformation ratio of the transformer being the unknown variable. The Jacobian matrix, which is constructed using the augmented matrix formulation, is expanded to hold the constraint equations of voltage regulators. The proposed new method is tested on a variety of test circuits including the large-scale IEEE 8500 Node Test Feeder, and the minimum number of iterations reported in the literature is achieved as presented in this paper.     

Epididymal manifestations of urogenital tuberculosis

We report the case of a 33-year-old man with a severe Crohn's disease since the age of sixteen. He presented with acne and palmoplantar pustulosis associated with a right knee synovitis. Investigations revealed a major axial bone condensation. The association synovitis-acne-pustulosis-hyperostosis-osteitis leaded to the diagnosis of SAPHO syndrome associated with Crohn's disease.     

The impact of a family planning multimedia campaign in Bamako, Mali

An integrated multimedia campaign featuring family planning messages saturated the 900,000-person city of Bamako, Mali, for three months during the spring of 1993. With traditional theater and music, family planning messages were repeatedly broadcast on radio and television that conveyed information about modern contraceptive methods, the need for male sexual responsibility, the health and economic advantages of family planning, the need for communication between spouses, and that Islam, the predominant faith of Mali, does not oppose family planning. A separate sample pretest-post-test quasi-experimental research design was used to evaluate the effects of the campaign and exposure to specific messages on changes in contraceptive knowledge, attitudes, and practice. Results indicate a high level of exposure to and agreement with the messages. A dramatic drop was found in the proportion of men and women who believe that Islam opposes family planning. Logistic regression results indicate that contraceptive knowledge and use and more favorable attitudes toward family planning are positively associated with intensity of exposure to the project interventions, after controlling for relevant variables.     

Women among a population at a psychiatric service in Senegal (psychosocial aspects)

Exposure of porin from Escherichia coli to glutardialdehyde followed by SDS-gel electrophoresis in 3% polyacrylamide yielded three bands that were identified in order of decreasing mobility as monomers and two and three cross-linked polypeptide chains. The distribution of protein among the three species for different extents of reaction showed a remarkably good agreement with corresponding values predicted from cross linking theory for an oligomer composed of three identical subunits arranged according to a 3-fold rotation axis. Electrophoresis performed in 7.5% polyacrylamide yielded four bands that were assigned to polypeptide chain monomers, dimers, and two types of trimers carrying two and three intersubunit cross-links. Our findings provide evidence that the central premise of cross-linking theory, viz. that the intersubunit cross-links formed upon exposure of a protein to a bifunctional reagent be governed by the symmetry of the molecule, is valid. Careful interpretation of cross-linking experiments thus proves an effective method to assess the oligomeric structure of a protein and reveal the symmetry underlying the spatial arrangement of the subunits within the molecule.     

The use of advance information for motor preparation in Parkinson's disease: effects of cueing and compatibility between warning and imperative stimuli

The ability of 13 Parkinsonian patients and 11 age-matched control subjects to process and use two components of the information given prior to a voluntary movement was studied using reaction time (RT) tasks. This advance information about the direction of a pointing movement was given using a double stimulation paradigm with an auditory warning signal (WS) which occurred prior to a visual imperative signal (IS). The first component of the information was given by the WS at the beginning of each trial, and the second component was the WS-IS compatibility during series of trials. The subjects were tested with three RT paradigms: a cued simple (CS) task, a cued choice (NC) task, and a priming choice (P) task. The results show that the normal subjects used both the lateral cue and the WS-IS compatibility to shorten their RTs, whereas the Parkinsonian patients were able to use the lateral warning signal, but their ability to use the degree of compatibility stimuli was impaired. These data suggest that when dealing with lateral cues in a RT task, Parkinsonian patients have no difficulty in identifying a stimulus and selecting the appropriate response, but that this is no longer so in the case of stimulus compatibility. This impairment may be due to attentional disorders involving a dysfunction affecting the medial premotor system, which includes the basal ganglia and may be responsible for the feedforward movement control deficits associated with Parkinson's disease.     

Path similarity evaluation using Bloom filters

The performance of several Internet applications often relies on the measurability of path similarity between different participants. In particular, the performance of content distribution networks mainly relies on the awareness of content sources topology information. It is commonly admitted nowadays that, in order to ensure either path redundancy or efficient content replication, topological similarities between sources is evaluated by exchanging raw traceroute data, and by a hop by hop comparison of the IP topology observed from the sources to the several hundred or thousands of destinations.In this paper, based on real data we collected, we advocate that path similarity comparisons between different Internet entities can be much simplified using lossy coding techniques, such as Bloom filters, to exchange compressed topology information. The technique we introduce to evaluate path similarity enforces both scalability and data confidentiality while maintaining a high level of accuracy. In addition, we demonstrate that our technique is scalable as it requires a small amount of active probing and is not targets dependent.