Quasi-separatrix layers and three-dimensional reconnection diagnostics for line-tied tearing modes

In three-dimensional magnetic configurations for a plasma in which no closed field line or magnetic null exists, no magnetic reconnection can occur, by the strictest definition of reconnection. A finitely long pinch with line-tied boundary conditions, in which all the magnetic field lines start at one end of the system and proceed to the opposite end, is an example of such a system. Nevertheless, for a long system of this type, the physical behavior in resistive magnetohydrodynamics (MHD) essentially involves reconnection. This has been explained in terms comparing the geometric and tearing widths [1, 2]. The concept of a quasi-separatrix layer[3, 4] was developed for such systems. In this paper we study a model for a line-tied system in which the corresponding periodic system has an unstable tearing mode. We analyze this system in terms of two magnetic field line diagnostics, the squashing factor[3-5] and the electrostatic potential difference used in kinematic reconnection studies[6, 7]. We discuss the physical and geometric significance of these two diagnostics and compare them in the context of discerning tearing-like behavior in line-tied modes. [1] G. L. Delzanno and J. M. Finn. Physics of Plasmas, 15(3):032904, 2008. [2] Y.-M. Huang and E. G. Zweibel. Physics of Plasmas, 16(4):042102, 2009. [3] E. R. Priest and P. D\'emoulin. J. Geophys. Res., 100(A12):23443-23463, 1995. [4] P. D\'emoulin, J. C. Henoux, E. R. Priest, and C. H. Mandrini. Astron. Astrophys., 308:643-655, Apr. 1996. [5] V. S. Titov and G. Hornig. Advances in Space Research, 29(7):1087-1092, 2002. [6] Y. Lau and J. M. Finn. The Astrophysical Journal, 350:672-691, Feb. 1990. [7] Y. Lau and J. M. Finn. The Astrophysical Journal, 366:577-591, 1991.Comment: 13 pages, 9 figures, Submitted to Commun Nonlinear Sci Numer Simula

Test offering, not additional information, may increase HIV testing uptake in a knowledgeable population

A CAJM journal article.Objectives: To evaluate patient HIV knowledge and testing experience and assess the effect of an HIV informational handout on HIV testing propensity. Design: Cross sectional, descriptive techniques were employed to assess demographics, HIV knowledge and HIV testing experience. A randomized controlled trial was performed to determine if an HIV/AIDS information sheet influenced testing propensity. Setting: Blantyre Adventist Hospital Outpatient Clinic. Subjects: Non-emergency patients over 18 years old attending during consulting hours. Interventions: All subjects answered a questionnaire. For the randomized controlled trial component, half received an HIV information handout. Main Outcome Measures: Proportions were calculated to evaluate testing experience. Logistic regression was used to assess impact of written information and demographics on HIV testing propensity. Results: 490 participants were recruited, of whom 57% had never been tested for HIV. Of the untested, 88% had never been offered an HIV test. Of those that had never been offered a test, 46% desired one. The sample was highly knowledgeable about HIV. Reading an information sheet had no impact on HIV knowledge (p=0.736 to 0.788) or desire for testing (p=0.387). However, age (OR=0.97,95%CI (0.95,0.99)) and gender (OR=1.85, 95%CI (1.06, 3.23)) significantly correlated with testing propensity. Conclusions: A large percentage of patients who have never been offered HIV testing desire testing. More frequent HIV test offering by clinicians could improve testing rates. Clinician education programmes should be developed to increase test offering. Furthermore, written health information in a setting of high HIV/AIDS knowledge may not change behaviour. Alternative methods should be employed to encourage HIV testing uptake

Intestinal myiasis in a Malaysian patient caused by larvae of Clogmia albipunctatus (Diptera: Psychodidae)

Clogmia albipunctatus (Duckhouse) is a cosmopolitan fly belonging to the family Psychodidae and is one of the medically important insects associated with urban environments ( Smith and Thomas 1979 ). Psychodid larvae can cause myiasis in humans through infestation of healthy or traumatized tissues ( Hall and Smith 1993 ). Human myiasis can be presented in various forms with cutaneous myiasis the most common form ( Tu et al. 2007 ). Other infestation sites include nasal, aural, pulmonary, ophthalmic cavities, body cavities, and the gastrointestinal and urogenital systems ( Tu et al. 2007 , El-Badry et al. 2014 ). Intestinal myiasis may result from accidental ingestion of larvae. Subsequently, this form of myiasis presents symptoms such as nausea, vomiting, abdominal pain and distention, loss of appetite, weight loss, and episodic diarrhea ( Ramana 2012 ). This is the second reported case of human intestinal myiasis in Malaysia caused by larvae of C. albipunctatus . Microscopic examination revealed the structure of the larvae and DNA barcoding established the species identity

Comparative study on membrane distillation application between raw POME and POMSE

The palm oil industry is considered the traditional pillar of Malaysian industry that plays a key role in the domestic economy. In addition to the high incomes generated by this industry, it generates large quantities of effluent. To solve this problem, the purpose of this work is to introduce membrane distillation (MD) technology for the effluent treatment system. Polyvinylidene fluoride (PVDF) -bentonite hollow fiber membranes were tested in an MD system using raw palm oil mill effluent (POME) and palm oil mill secondary effluent (POMSE). Preliminary test was carried out using deionized water to evaluate the maximum permeate flux achievable in the absence of fouling problem before continuing with POME and POMSE as the feed solution. Membrane performance was evaluated in terms of permeate flux and rejection rate of several water quality parameters. The average permeate flux obtained while using raw POME is much lower than that obtained in the POMSE test which was recorded as 1.41 ± 0.62 kg/m2.hr and 3.45 ± 0.51 kg/m2.hr respectively. The membrane tested for POME experienced a significant decrease in flux relative to POMSE due to the excessive amounts of biological compounds blocking the membrane pores. In terms of removal efficiency of the PVDF-bentonite membrane, the membranes were able to achieve more than 95% removal efficiency for chemical oxygen demand, nitrate nitrogen, total suspended solids, total dissolved solids, color and turbidity. The results proved that the DCMD system was able to eliminate almost all pollutants in the effluent from oil palm industry. However, raw POME without pre-treatment is not suitable to be used directly in the DCMD process because it will cause a serious fouling problem. In conclusion, it can be said that MD has shown excellent performance in the treatment of palm oil wastewater and can be applied to other types of oil industries

Deficiency of the miR-29a/b-1 cluster leads to ataxic features and cerebellar alterations in mice

miR-29 is expressed strongly in the brain and alterations in expression have been linked to several neurological disorders. To further explore the function of this miRNA in the brain, we generated miR-29a/b-1 knockout animals. Knockout mice develop a progressive disorder characterized by locomotor impairment and ataxia. The different members of the miR-29 family are strongly expressed in neurons of the olfactory bulb, the hippocampus and in the Purkinje cells of the cerebellum. Morphological analysis showed that Purkinje cells are smaller and display less dendritic arborisation compared to their wildtype littermates. In addition, a decreased number of parallel fibers form synapses on the Purkinje cells. We identified several mRNAs significantly up-regulated in the absence of the miR-29a/b-1 cluster. At the protein level, however, the voltage-gated potassium channel Kcnc3 (Kv3.3) was significantly up-regulated in the cerebella of the miR-29a/b knockout mice. Dysregulation of KCNC3 expression may contribute to the ataxic phenotype

A possible rheological model of gum candies

An appropriate rheological model can be used in production of good quality gum candy required by consumers. For this purpose Creep-Recovery Test (CRT) curves were recorded with a Stable Micro System TA.XT-2 precision texture analyser with 75 mm diameter cylinder probe on gum candies purchased from the local market. The deformation speed was 0.2 mm s−1, the creeping- and recovering time was 60 s, while the loading force was set to 1 N, 2 N, 5 N, 7 N, and 10 N. The two-element Kelvin-Voigt-model, a three-element model, and the four-element Burgers-model were fitted on the recorded creep data, and then the parameters of the models were evaluated. The best fitting from the used models was given by the Burgers model

Bilingual Learning for Second and Third Generation Children

Throughout the English-speaking world, children from bilingual backgrounds are being educated in mainstream classrooms where they have little or no opportunity to use their mother tongue. Second and third generation children, in particular, are assumed to be learning sufficiently through English only. This study investigated how British Bangladeshi children, learning Bengali in after-school classes but mostly more fluent in English than in their mother tongue, responded when able to use their full language repertoire within the mainstream curriculum. Through action research with mainstream and community language class teachers, bilingual literacy and numeracy tasks were devised and carried out with pupils aged seven to eleven in two East London primary schools. The bilingual activities were videorecorded and analysed qualitatively to identify the strategies used. The following cognitive and cultural benefits of bilingual learning discovered by researchers in other contexts were also found to apply in this particular setting: conceptual transfer, enriched understanding through translation, metalinguistic awareness, bicultural knowledge and building bilingual learner identities. The findings suggest that second and third generation children should be enabled to learn bilingually, and appropriate strategies are put forward for use in the mainstream classroom

Search for the Flavor-Changing Neutral Current Decay D0→μ+μ−D^0 \to \mu^+\mu^- with the HERA-B Detector

We report on a search for the flavor-changing neutral current decay $D^0 \to \mu^+\mu^-$ using $50 \times 10^6$ events recorded with a dimuon trigger in interactions of 920 GeV protons with nuclei by the HERA-B experiment. We find no evidence for such decays and set a 90% confidence level upper limit on the branching fraction $Br(D^0 \to \mu^+\mu^-) <2.0 \times 10^{-6}$.Comment: 17 pages, 4 figures (of which 1 double), paper to be submitted to Physics Letters