Disassembly of the Coliphage λ Replication Complex Due to Heat Shock Induction of thegroEOperon

AbstractWe have found previously that, in contrast to the free O initiator protein of λ phage or plasmid rapidly degraded by theEscherichia coliClpP/ClpX protease, the λO present in the replication complex (RC) is protected from proteolysis. In amino acid-starvedE. coli relAcells, a temperature shift from 30 to 43° did not affect RC integrity, as judged from the unchanged level of stable λO observed; however, the same temperature shift in a complete medium resulted in the decay of this λO fraction, which suggested disassembly of the RC. Examination of this phenomenon revealed that for λ RC disassembly, heat shock induction of thegroEoperon, coding for molecular chaperones of the Hsp60 class, is indispensable. Heat shock induction of thegroEoperon present on a multicopy plasmid inhibited the growth of infecting phage

Promoting e-Learning Educational Programs for Wellness and SPA Therapies

AbstractPromoting lifelong learning in the field of health is the result of continuous professional skills development through accessing the most recent knowledge and large data bases of specialty. Spa treatment is integrated with kinesitherapy and rehabilitation medicine and it is a methodical and therapeutic specialty for studying and applying into practice physical means (warmth, light, electricity, etc) and natural therapeutic factors (climate, mineral waters, mud) combined with physical exercise under its prophylactic, therapeutic and rehabilitation aspects

Training senior teachers in compulsory computer based language tests

AbstractThe IBT TOEFL has become the principal example of online high stakes language testing since 2005. Most instructors who do the preparation for IBT TOEFL face two main realities: first, students are eager and highly motivated to take the test because of the prospective implications; and, second, specific studies would be necessary to see if instructors may be familiarized with the use of computers in teaching and/or language testing for other high stakes tests. Now, many standardized tests are going online as well such as IELTS, BULATS and others (García Laborda, 2007). National Boards of Education are also considering this possibility for the national university entrance examination (PAU) (García Laborda & Magal Royo, 2007; García Laborda, 2006). However, in this case, teachers may not be willing or well prepared to face the challenge due to factors such as ICT familiarity. To date, many papers have explored the role of teacher training in their adaptation to the inclusion or implementation of ICT in the foreign language classroom (Zepp, 2005; Tan et al., 2003; Rehbein et al., 2003). However, it is necessary to consider the differences between the use of ICT for language testing (as opposed to general teaching) and the profile of senior high school foreign language teachers who may not be as flexible as their younger colleagues. This paper describes the trainees’ final attitudes of a six-month course held in Valencia (Spain). 26 teachers from private schools who teach many of the students who take the test every year participated in an in-service teacher training course in Valencia. Instructional methods principally included training in ICT strategy and use through face-to-face instruction and also autonomous learning, group work, synchronous and asynchronous communication, and computer based test design. The teachers’ responses to long discussions in a control session and to a questionnaire, along with the observations of a 20-hour course and the results of the familiarization with different tools show that for this type of training it is not only necessary to familiarize teachers with the testing tool but also with the process of creating online tests and with the testing process itself (Chapelle & Douglas, 2006; Stoynoff & Chapelle, 2005). Results from the platform use and the final questionnaire indicated that the majority of trainees reacted positively to the training and were eager to let the research team work with their students. However, they still felt they would not be able to use ICT for testing in their classes

Visual Representations in Mathematical Word Problem Solving Among Form Four Students in Malacca

AbstractLearning how to solve mathematical problems has been a long withstanding difficulty faced by students and has been given constant focus in mathematical development. Successful problem solvers spend more time analyzing a problem and they will find all the alternatives related to the situation. Therefore many educators (Cai, 2003, National Council of Teachers of Mathematics, 2000; Smith, 1991) agreed that teaching mathematics through problem solving hold great promise. Furthermore, according to the Malaysian Curriculum Development Centre (2003), one of the important objectives in teaching mathematics is to develop student's mathematical problem solving skills. Mathematical problems are not simply computational tasks type but are problems which also require appropriate selection of strategies and decisions that lead to logical solutions. Word problem solving is one of the important components of mathematics problem solving which incorporate real-life problems and applications. However, many researches revealed that students express great difficulties in handling a word or story problem. This study examined the use of visual representations which posed great difficulties in most mathematical tasks. Secondary students were given the 15Mathematical Processing Instrument (MPI) adapted from Hegarty and Kozhevnikov (1999). This study examined 381 students from eight secondary schools in three different districts in Malacca. Results indicated that less than two percent of the problems were solved using pictorial representation and most of the students preferred to used schematics solutions

Effects of in vitro potassium on ammoniagenesis in rat and canine kidney tissue

Effects of in vitro potassium on ammoniagenesis in rat and canine kidney tissue. Decreased ammonium (NH4+) excretion is associated with hyperkalemia. To determine if potassium could directly influence renal ammonia production, we investigated ammoniagenesis by rat and canine renal cortical tissues in vitro at different potassium concentrations. Renal tissue from normal and acidotic rats and normal dogs incubated in glutamine, lactate, and 7 to 10mEq/liters of potassium or 25mEq/liters of potassium produced significantly less ammonia than slices incubating in glutamine, lactate, and 4 to 5mEq of potassium. Glutamate accumulation, which follows glutamine deamidation, did not decrease and even increased at 25mEq/liters of potassium. With glutamine as the sole substrate, decreased ammoniagenesis was seen only at higher potassium concentrations (> 16mEq/liters) than when lactate was also present. The depression to glutamine ammoniagenesis by high concentrations of potassium was partially obliterated in an anaerobic environment. When glutamate replaced glutamine as the precursor, renal ammonia produced by slices in 7 and 25mEq/liters was again significantly lower than by slices incubating in 4mEq/liters. We blocked glutamine synthesis by rat kidney slices with dl-methionine dl-sulfoximine when glutamate was the renal ammonia precursor. This essentially allows glutamate deamination to produce ammonia. Potassium depressed glutamate deamination significantly at 7mEq/liters (↓ 13%) and at 25mEq/liters of potassium (↓ 35%) as compared to 4mEq/liters. The above findings are consistent with a major depressive effect of in vitro potassium on glutamate deamination in rat and canine kidneys. Other evidence, especially from rat tissue studies, suggests that potassium also may affect glutamine deamination directly. Rat kidney slices incubating in the high potassium medium of 7mEq/liter or greater also consumed less oxygen in the presence of glutamine (P < 0.01), oxidatively decarboxylated less glutamine (P < 0.02) and produced less glucose from glutamine (P < 0.01).Effet du potassium in vitro sur l'ammoniogenèse dans tissu rénal de rat et de chien. Une diminution de l'excrétion d'ammoniaque (NH4+) est associée à l'hyperkaliémie. Afin de déterminer si le potassium peut influencer directement la production rénale d'ammoniac, nous avons étudié l'ammoniogenèse dans le tissu rénal cortical de rat et de chien in vitro à différentes concentrations de potassium. Du tissu rénal provenant de rats normaux et en acidose et de chiens normaux incubés dans de la glutamine, du lactate, et 7 à 10mEq/litres de potassium ou 25mEq/litres de potassium produit significativement moins d'ammoniac que des tranches incubées dans de la glutamine, du lactate, et 4 à 5mEq/litres de potassium. L'accumulation de glutamate, consécutive à la deamination de la glutamine, n'a pas diminué et même a augmenté à 25mEq/litres de potassium. Avec la glutamine comme seul substrat, la diminution de l'ammoniogenèse n'a été observée qu'à des concentrations de potassium supérieures (> 16mEq/litres) à celle nécessaire quand le lactate est présent. La dépression de l'ammoniogenèse due à la glutamine au moyen de concentrations élevées de potassium est partiellement abolie par un environnement anaérobique. Quand la glutamine est remplacée par du glutamate, le rénale d'ammoniac produit par des tranches dans des milieux à 7mEq/litres et 25mEq/litres est là encore significativement inférieur à celui produit par des tranches incubées dans un milieu à 4mEq/litres. Nous avons bloqué la synthèse de glutamine dans les tranches de rein de rat au moyen de la dl-méthionine dl-sulfoximine quand le glutamate était le précurseur de rénale d'ammoniac. Ceci permet à la déamination du glutamate de produire de l'ammoniac. Potassium diminue significativement la déamination du glutamate à 7mEq/litres (diminution de 13%), et à 25mEq/litres (diminution de 35%) par comparaison avec les valeurs obtenues à 4mEq/litres. Ces constatations sont compatibles avec un effet dépresseur majeur du potassium in vitro sur la déamination du glutamate dans les reins de rat et de chien. D'autres arguments, tirés essentiellement des études sur le tissu de rat, suggèrent que le potassium peut aussi affecter la déamination du glutamate directement. Des tranches de rein de rat incubées dans un milieu riche en potassium (7mEq/litres ou plus) consomment moins d'oxygène en présence de glutamine (P < 0,01), décarboxylent moins de glutamine par oxydation (P < 0,02) et produisent moins de glucose à partir de la glutamine (P < 0,01)

Confluent q-extensions of some classical determinants

AbstractWe evaluate two determinants. The first is a q,h-extension of the classical confluent extension of the Vandermonde determinant. The second is a similar extension of Cauchy’s double alternant

The impacts of a fliD mutation on the biofilm formation of Helicobacter pylori

AbstractObjectiveTo investigate the impact of the fliD gene on the biofilm formation of Helicobacter pylori (H. pylori).MethodsH. pylori fliD mutant was constructed using inverse PCR mutagenesis. The mobility of the bacteria and its adhesion ability to human epithelial cells were assessed using a motility assay and a fluorescein isothiocyanate staining adhesion assay, respectively. The formation of biofilm was evaluated using a pellicle assay and a crystal violet staining assay. The cyto-architecture of the biofilm was documented with scanning electron microscopy.ResultsIt was found that there was no significant difference in the levels of bacterial adhesion and the biofilm formation between the wild-type ATCC 43504 and the fliD mutant. Apart from a poor motility, the fliD mutant had a slightly delayed formation of its biofilm and an incomplete cyto-architecture of its biofilm. The bacterial cells residing in the biofilm of the fliD mutant showed a loose accumulation with less apparent cross-linking fibrils. Most of the mutant cells had truncated flagella.ConclusionsThis study provides the preliminary evidences that fliD potentially regulates biofilm formation and is required for the motility of H. pylori. Further studies need to be performed in order to develop fliD as a novel target for vaccine or antimicrobial agent in future

Design of New Oscillograph Based on FPGA

AbstractOscillograph is one of the necessary measurement instruments in modern electronic design field. A new type of Oscillograph based on FPGA is proposed and designed in this paper. It consists of oscillograph, logic analyzer and signal generator. The resolution of the oscillograph is 8 bit and the maximum value can reach 200Mbps with support of software based on windows operation system. That of the logic analyzer is 100 Msps with 16 channels. The resolution of signal generator is 140Msps with 10-bit

Insertion and hairpin formation of membrane proteins: a Monte Carlo study

Some particular effects of a lipid membrane on the partitioning and the concomitant folding processes of model proteins have been investigated using Monte Carlo methods. It is observed that orientational order and lateral density fluctuations of the lipid matrix stabilize the orientation of helical proteins and induce a tendency of spontaneous formation of helical hairpins for helices longer than the width of the membrane. The lateral compression of the lipids on a hairpin leads to the extrusion of a loop at the trans side of the membrane. The stability of the hairpin can be increased by the design of appropriate groups of hydrophilic and hydrophobic residues at the extruded loop. It is shown that in the absence of lipids the orientation of proteins is not stable and the formation of hairpins is absent. Some analogies between the formation of helical hairpins in membranes and the formation of hairpins in polymer liquid crystals are discussed. The simulations indicate that the insertion process follows a well-defined pattern of kinetic steps