Assessing the Nature of Science Views of Singaporean Pre-Service Teachers

Despite the many developments in the teaching of science, an aspect that continues to be neglected appears to be the character and nature of science (NOS). This is becoming especially important in the light of recent developments in pedagogy, as, for example, more teachers adopt constructivist methodologies and computing technology enables simulations that may blur the lines between models and reality. From the literature, it is known that teachers\u27 modern NOS conceptions, though not a sufficient condition for transmission of modern NOS views, is necessary. In this study, pre-service teachers\u27 NOS conceptions are assessed with an adapted Views of the Nature of Science (VNOS) instrument, originally designed by Lederman, Abd-El-Khalick, Bell, and Schwartz (2002). The modified instrument is an eight-item, open ended questionnaire – designed to elicit descriptive responses to common NOS misconceptions. Responses were analysed into coded categories of ‘informed, ‘uninformed, and ‘ambiguous’. It was found that a significant proportion of teachers possessed uninformed views. Some implications for teaching and teacher education are presented in this paper for discussion

Cholinergic Muscarinic Receptor: Biochemical and Light Autoradiographic Localization in the Brain

The muscanmc cholinergic antagonist 3-quinudidinyl benzilate (QNB) binds avidly but reversibly to the muscarinic cholinergic receptor of mammalian brain and peripheral tissues. [3H]-QNB binding provides a simple, sensitive and specific assay for the muscarinic cholinergic receptor binding. Inhibition of [3H]-QNB binding to homogenates of brain and guinea pig ileum by muscarinic drugs correlates with their pharmacologic potencies, while nicotinic agents and noncholinergic drugs have negligible affinity. The regional distribution of [3H]-QNB binding throughout rat and monkey brain parallels to a major extent other cholinergic markers, suggesting that the majority of cholinergic synapses in the brain are muscarinic. [3H]-QNB accumulation in various brain regions after intravenous injection provides a means of labelling the muscarinic receptor in vivo. By labelling the receptor in vivo, autoradiographic studies under the light microscope have been performed to visualize the muscarinic receptor

Bojungikgitang and banhabaekchulchonmatang in adult patients with tinnitus, a randomized, double-blind, three-arm, placebo-controlled trial - study protocol

<p>Abstract</p> <p>Background</p> <p>Tinnitus is the perception of hearing a sound for which there is no external acoustic source. It is often associated with sudden, temporary hearing loss and has a clear impact on a patient's quality of life. Despite numerous trials, there are no treatments that can be considered well established in terms of providing replicable long-term tinnitus reduction. Complementary and alternative medical approaches have been employed to relieve symptoms of tinnitus. Bojungikgitang and banhabaekchulchonmatang are among the most strongly preferred and widely used herbal medicines for tinnitus in Korea, as they cause very few serious adverse effects.</p> <p>We aim to establish basic clinical efficacy and safety data for bojungikgitang and banhabaekchulchonmatang, which are approved as herbal medications by the Korea Food and Drug Administration in adult patients with tinnitus.</p> <p>Methods/Design</p> <p>This study was a randomised, double-blind, placebo-controlled trial with three parallel arms (bojungikgitang, banhabaekchulchonmatang, and a placebo). Participants included in the study met the following criteria: typical conditions of intermittent or continuous tinnitus, for more than three months, with involuntary perceptions of the concept of a sound in the absence of an external source. Participants received bojungikgitang, banhabaekchulchonmatang, or a placebo-drug for eight weeks. The total duration of each arm was eleven weeks. Each participant was examined for signs and symptoms of tinnitus before and after taking medication. Post-treatment follow-up was performed two weeks after the final administration of medication.</p> <p>Discussion</p> <p>This trial provided evidence for the efficacy and safety of bojungikgitang and banhabaekchulchonmatang in adult patients with tinnitus. The primary outcome measure was the Tinnitus Handicap Inventory, an assessment used to identify difficulties that may be experienced due to tinnitus. The secondary measures were included an Acoustic Examination and the Visual Analogue Scale. We employed the Euro-Qol 5-Dimension and the Health Utilities Index Mark 3, a health-related quality of life questionnaire. Safety was assessed by complete blood cell count, erythrocyte sedimentation rate, blood chemistry, urine analysis, PA chest film, brain computed tomography, otologic examination, and vital signs.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN23691284</p

Understanding economic evidence for the prevention and treatment of atopic eczema

Background Atopic eczema is an inflammatory skin condition, with a similar impact on health-related quality-of-life as other chronic diseases. Increasing pressures on resources within the NHS increase the importance of having good economic evidence to inform their allocation. This paper aims to educate dermatologists about economic methods with illustration to currently available economic evidence on eczema. Methods/design The type and role of different types of economic evidence is illustrated by evidence found in a systematic literature search conducted across 12 online databases published until 22nd May 2017. Primary empirical studies either reporting the results of a cost of illness study or evaluating the cost, utility or full economic evaluation of interventions for preventing or treating eczema were included. Two reviewers independently assessed studies for eligibility and performed data abstraction, with disagreements resolved by a third reviewer. Evidence tables of results were produced for narrative discussion. The reporting quality of economic evaluations was assessed. Results 78 studies (described in 80 papers) were deemed eligible. 33 (42%) were judged to be economic evaluations, 12 (15%) cost analyses, 6 (8%) utility analyses, 26 (34%) cost-of-illness studies and 1 feasibility study (1%). The calcineurin inhibitors: tacrolimus and pimecrolimus, as well as barrier creams had most economic evidence available. Partially hydrolysed infant formula was the most commonly evaluated prevention. Conclusions The current level of economic evidence for interventions aimed at preventing and treating eczema is limited compared to that available for clinical outcomes suggesting that greater collaboration between clinicians and economists might be beneficial

Identification of Nucleases and Phosphatases by Direct Biochemical Screen of the Saccharomyces cerevisiae Proteome

The availability of yeast strain collections expressing individually tagged proteins to facilitate one-step purification provides a powerful approach to identify proteins with particular biochemical activities. To identify novel exo- and endo-nucleases that might function in DNA repair, we undertook a proteomic screen making use of the movable ORF (MORF) library of yeast expression plasmids. This library consists of 5,854 yeast strains each expressing a unique yeast ORF fused to a tripartite tag consisting of His6, an HA epitope, a protease 3C cleavage site, and the IgG-binding domain (ZZ) from protein A, under the control of the GAL1 promoter for inducible expression. Pools of proteins were partially purified on IgG sepharose and tested for nuclease activity using three different radiolabeled DNA substrates. Several known nucleases and phosphatases were identified, as well as two new members of the histidine phosphatase superfamily, which includes phosphoglycerate mutases and phosphatases. Subsequent characterization revealed YDR051c/Det1 to be an acid phosphatase with broad substrate specificity, whereas YOR283w has a broad pH range and hydrolyzes hydrophilic phosphorylated substrates. Although no new nuclease activities were identified from this screen, we did find phosphatase activity associated with a protein of unknown function, YOR283w, and with the recently characterized protein Det1. This knowledge should guide further genetic and biochemical characterization of these proteins

A Nonpeptidic Delta Opiold Receptor Agonist, BW373U86, Attenuates the Development and Expression of Morphine Abstinence Precipitated by Naloxone in Rat

ABSTRACT The effect o

Single-event-transient resilient memory for DSP in space applications

We present a radiation-hardened-by-design (RHBD) memory design that mitigates Single-Event-Transients (SETs), Single-Event-Upsets (SEUs) and Dual-Event-Upsets (DEUs), hence significantly enhancing the reliability of digital signal processors (DSPs) for space applications. We achieve these attributes by combining a Triple-Interlocked Cell (TICE) SRAM cell array and a Triple Modular Redundancy (TMR) voter. The TICE SRAM cells therein self-correct SEUs and DEUs. The TMR voter eliminates SETs. Our proposed RHBD TICE SRAM cells integrated with the TMR voter are also hardened by the layout/sizing RHBD practices. By means of the 128×9-bit memory implementation @ 65nm CMOS, we show that our memory design is inherent SEUand DEU-tolerant, and has 94.83% SET reduction and 92.05% Triple-Event-Upset (TEU) reduction when compared to the memory design embodying the 8-transistor (8-T) SRAM cells.MOE (Min. of Education, S’pore)Accepted versio

Counteracting differential power analysis: Hiding encrypted data from circuit cells

We propose a balanced Pre-Charge Static Logic (PCSL) circuit style for asynchronous systems, and compare it against other reported circuit styles to counteract differential power analysis (DPA). Our study shows that all these circuit styles (including our balanced PCSL) dissipate different energy due to data-dependency, and hence balancing the energy of circuits embodying these circuit styles remains challenging. However, in view of low circuit overheads and asynchronous operations (with noise generation), our balanced PCSL is still competitive in terms of DPA-resistance, requiring 3.5x less power traces than its NULL convention logic counterpart.ASTAR (Agency for Sci., Tech. and Research, S’pore)Accepted versio