An Analytical Solution to Circular Touch Mode Capacitor

In this paper, a simple but accurate analytical solution is presented to model the flexion of a circular diaphragm with clamped edges under an uniform load. The touch down effect and the evolution of touch radius are considered in this model, making it useful for touch down capacitor devices such as pressure sensors. This model is then compared to results obtained from Coventor, a finite elements analysis program designed for microelectromechanical systems     

Production of probiotic cheese (cheddar-like cheese) using enriched cream fermented by Bifidobacterium infantis.

Probiotic cheeses (Cheddar-like cheese) were produced with microfiltered milk standardized with cream enriched with native phosphocaseinate retentate and fermented by Bifidobacterium infantis. During the manufacture and storage of cheeses, viability of the bifidobacteria was determined. Biochemical changes such as proteolysis, sugar metabolism, and organic acids production were estimated. No bifidobacteria growth was observed during cheese-making steps. Bifidobacteria survived very well in cheeses packed in vacuum sealed bags kept at 4 degrees C for 84 d and remained above 3 x 10(6) cfu/g of cheese. No significant difference was observed between cheeses produced with or without bifidobacteria for fat, protein, moisture, salt, ash, or pH. After 12 wk of storage, more than 56% of the as1-CN was hydrolyzed in cheeses that were produced with bifidobacteria and inoculated at 10(8) cfu/g in the cream, and > 45% of hydrolysis was observed in the control cheese. However, no significant differences in the electrophoretic sodium dodecyl sulfate-PAGE patterns were observed in cheeses at any period of storage. At the first day after manufacture, lactose was completely hydrolyzed in cheeses made with bifidobacteria, which suggested high beta-galactosidase activity by B. infantis. Small quantities of acetic acid were detected in bifidus cheeses. The results indicated that B. infantis introduced into hard pressed cheese exhibited excellent viability during storage for 12 wk and could be metabolically active.     

Models for Analysis of Packet Voice Communications Systems

In a packet voice communication system, packets are fed to a common queue by a number of independent voice sources and are removed from this queue on a first-come-first-serve basis for transmission over a communication link of finite capacity. Each voice source alternates between active periods, during which packets are generated at regular intervals, and inactive periods, during which no packets are generated. In this paper, we discuss three models, a semi-Markov process model, a continuous-time Markov chain model, and a uniform arrival and service model, to assess the queueing behavior of such systems. Numerical results obtained from each of the three models are compared to each other, to results obtained from a discrete event simulation program, and to results obtained from anM/D/1analysis. Parameters of the model are the average duration of active and inactive periods, the packet generation rate, the communication link capacity, and the total number of voice sources. Conclusions are drawn regarding which models appear to be most appropriate in the parameter ranges investigated.     

Expression and detection of pap-, sfa-, and afa-encoded fimbrial adhesin systems among uropathogenic Escherichia coli

Thirty-five Escherichia coli isolates from young children and women with pyelonephritis, cystitis, or asymptomatic bacteriuria were characterized genotypically and phenotypically. The isolates were examined genotypically by using DNA probes specific for the hemolysis gene and for the pap, sfa, and afa adhesin systems. Genes for the adhesin systems were also detected by polymerase chain reaction, using multigene amplification. The isolates were serotyped, tested for hemolysin production, and classified for their adhesion specificity by hemagglutination and by binding specificity assays. Twenty-seven of the 35 isolates were pap positive. Results showed that pap-positive isolates expressing class I or class II G adhesins were more frequent in cases of pyelonephritis than in cases of cystitis and asymptomatic bacteriuria. Expression of the class III G adhesins was more frequent in isolates from cystitis and asymptomatic bacteriuria than in isolates from pyelonephritis. Multiple adhesin systems and hemolysin were more frequently found in isolates from cases of pyelonephritis than in isolates from cases of cystitis and asymptomatic bacteriuria. There was perfect correlation between the results obtained by polymerase chain reaction and and those obtained by hybridization.     

Suicide prevention through means restriction: assessing the risk of substitution. A critical review and synthesis

The effectiveness of restricting access to certain means of committing suicide has been demonstrated, at least as regards toxic domestic gas, firearms, drugs and bridges. At the individual level, studies tend to indicate that many persons have a preference for a given means, which would limit the possibility of substitution or displacement towards another method. Similarly, the fact that suicidal crisis are very often short-lived (and, what is more, influenced by ambivalence or impulsiveness) suggests that an individual with restricted access to a given means would not put off his plans to later or turn to alternative methods. This has been more difficult to demonstrate scientifically in population studies. Nevertheless, it appears that, should such a shift occur towards other means, it would be put into effect only in part and over a longer term.     

Planar circular loop antennas with self-biased magnetic film loading

A circular loop antenna with self-biased magnetic film loading at 1.7 GHz is presented. The proposed circular loop antenna is realised by cascading a microstrip loop and a tuning stub. Self-biased NiCo-ferrite magnetic films were used to tune the working frequency of the loop antenna. Three different cases of antennas with films loading were designed and analysed. Antennas with self-biased magnetic films loading working at 1.7 GHz with a tuning range of 50-400% of the antenna bandwidth were achieved.     

Le stress per?u et son influence sur le comportement alimentaire des étudiants de l'Université de Moncton, Campus de Moncton

Objectif. Mesurer et analyser le lien entre le stress per?u et le comportement alimentaire d'étudiants de première (Et1) et de quatrième année (Et4) à l'Université de Moncton au début (T1) et à la fin (T2) du trimestre universitaire. Méthodes. Quatre-vingt-quatorze sujets de divers programmes universitaires ont participé à l'étude. Le stress per?u a été mesuré à l'aide de la Perceived Stress Scale, la consommation alimentaire par un journal alimentaire de trois jours et la fréquence de consommation alimentaire par un questionnaire de fréquence. Résultats. Au début du trimestre, les Et1 et Et4 présentent un niveau de stress faible. Au T2, le stress per?u des Et4 augmente significativement (22,3+/-1,4; p=0,005). Le profil alimentaire mesuré selon le niveau de conformité au "Guide alimentaire canadien pour manger sainement" montre, avec l'accroissement du stress, une augmentation de la consommation de lait et produits laitiers (p=0,05) chez les Et1,T1 et de produits céréaliers (p=0,02) chez les Et4,T2. Une corrélation négative significative est observée chez les Et4 entre le stress per?u et l'ingestion de thiamine (r=-0,48, p=0,006) et de zinc (r=-0,42, p=0,02). Aucune corrélation n'est observée entre le stress, l'apport en calories et la consommation des autres nutriments étudiés. Conclusion. Ces résultats révèlent l'importance d'intervenir auprès des étudiants universitaires et d'implanter des sessions d'information favorisant la gestion du stress et l'adoption de comportements alimentaires sains.     

Mercury release from deforested soils triggered by base cation enrichment

The Brazilian Amazon has experienced considerable colonization in the last few decades. Family agriculture based on slash-and-burn enables millions of people to live in that region. However, the poor nutrient content of most Amazonian soils requires cation-rich ashes from the burning of the vegetation biomass for cultivation to be successful, which leads to forest ecosystem degradation, soil erosion and mercury contamination. While recent studies have suggested that mercury present in soils was transferred towards rivers upon deforestation, little is known about the dynamics between agricultural land-use and mercury leaching. In this context, the present study proposes an explanation that illustrates how agricultural land-use triggers mercury loss from soils. This explanation lies in the competition between base cations and mercury in soils which are characterized by a low adsorption capacity. Since these soils are naturally very poor in base cations, the burning of the forest biomass suddenly brings high quantities of base cations to soils, destabilizing the previous equilibrium amongst cations. Base cation enrichment triggers mobility in soil cations, rapidly dislocating mercury atoms. This conclusion comes from principal component analyses illustrating that agricultural land-use was associated with base cation enrichment and mercury depletion. The overall conclusions highlight a pernicious cycle: while soil nutrient enrichment actually occurs through biomass burning, although on a temporary basis, there is a loss in Hg content, which is leached to rivers, entering the aquatic chain, and posing a potential health threat to local populations. Data presented here reflects three decades of deforestation activities, but little is known about the long-term impact of such a disequilibrium. These findings may have repercussions on our understanding of the complex dynamics of deforestation and agriculture worldwide.     

Task-Oriented Queueing: An Analysis Tool for Software Design of Communication Processing Systems

Jobs associated with messages arriving to a communication processing system (CPS) can be described as ordered sets of prioritized tasks, where each task represents the execution of some part of the system's software. The service system of the CPS consists of a collection of queues, one for each distinct priority, serviced by a single server under a preemptive resume discipline. The routing of the job through this collection of queues is defined by a job's priority vector which specifies the priority at which each task in the job is to execute. For example, if a two-task job's priority vector is (3, 2), then the job first joins the priority 3 queue, obtains service for the first task, then joins the priority 2 queue. In a previous paper, the author and a colleague described a method through which average delays in such task-oriented processing systems could be computed for the special case in which all jobs have identical structure. This paper presents a substantially simplified version of the analysis methodology presented previously and extends that work to the case of a finite number of job classes, each job class having a finite number of tasks.