Silicon spin diffusion transistor: materials, physics and device characteristics

The realisation that eaveryday electronics has ignored the spin of the carrier in favour of its charge is the foundation of the field of spintronics. Starting with simple two-terminal devices based on GMR and tunnel magnetoresistance, the technology has advanced to consider three-terminal devices that aim to combine spin sensitivity with a high current gain and a large current output. These devices require both efficient spin injection and semiconductor fabrication. In this paper, a discussion is presented of the design, operation and characteristics of the only spin transistor that has yielded a current gain greater than one in combination with reasonable output current

Strategies for using cellular automata to locate constrained layer damping on vibrating structures

It is often hard to optimise constrained layer damping (CLD) for structures more complicated than simple beams and plates as its performance depends on its location, the shape of the applied patch, the mode shapes of the structure and the material properties. This paper considers the use of cellular automata (CA) in conjunction with finite element analysis to obtain an efficient coverage of CLD on structures. The effectiveness of several different sets of local rules governing the CA are compared against each other for a structure with known optimum coverage-namely a plate. The algorithm which attempts to replicate most closely known optimal configurations is considered the most successful. This algorithm is then used to generate an efficient CLD treatment that targets several modes of a curved composite panel. To validate the modelling approaches used, results are also presented of a comparison between theoretical and experimentally obtained modal properties of the damped curved panel

Concise Review:Dental Pulp Stem Cells: A Novel Cell Therapy for Retinal and Central Nervous System Repair

Dental pulp stem cells (DPSC) are neural crest-derived ecto-mesenchymal stem cells that can relatively easily and non-invasively be isolated from the dental pulp of extracted postnatal and adult teeth. Accumulating evidence suggests that DPSC have great promise as a cellular therapy for central nervous system (CNS) and retinal injury and disease. The mode of action by which DPSC confer therapeutic benefit may comprise multiple pathways, in particular, paracrine-mediated processes which involve a wide array of secreted trophic factors and is increasingly regarded as the principal predominant mechanism. In this concise review, we present the current evidence for the use of DPSC to repair CNS damage, including recent findings on retinal ganglion cell neuroprotection and regeneration in optic nerve injury and glaucoma. Stem Cells 2017;35:61–67

You’ll never walk alone: supportive social relations in a football and mental health project

Football can bring people together in acts of solidarity and togetherness. This spirit is most evocatively illustrated in the world renowned football anthem You’ll Never Walk Alone (YNWA). In this paper we argue that this spirit can be effectively harnessed in nursing and mental health care. We draw on data from qualitative interviews undertaken as part of evaluating a football and mental health project to explore the nature of supportive social relations therein. We use some of the lyrics from YNWA as metaphor to frame our thematic analysis. We are especially interested in the interactions between the group facilitators and group members, but also address aspects of peer support within the groups. A contrast is drawn between the flexible interpersonal boundaries and self-disclosure evident in the football initiative and the reported more distant relations with practitioners in mainstream mental health services. Findings suggest scope for utilising more collective, solidarity enhancing initiatives and attention to alliances and boundaries to maximise engagement and therapeutic benefits within routine practice

Are transnational tobacco companies' market access strategies linked to economic development models? A case study of South Korea.

Transnational tobacco companies (TTCs) have used varied strategies to access previously closed markets. Using TTCs' efforts to enter the South Korean market from the late 1980s as a case study, this article asks whether there are common patterns in these strategies that relate to the broader economic development models adopted by targeted countries. An analytical review of the existing literature on TTCs' efforts to access emerging markets was conducted to develop hypotheses relating TTCs' strategies to countries' economic development models. A case study of Korea was then undertaken based on analysis of internal tobacco industry documents. Findings were consistent with the hypothesis that TTCs' strategies in Korea were linked to Korea's export-oriented economic development model and its hostile attitude towards foreign investment. A fuller understanding of TTCs' strategies for expansion globally can be derived by locating them within the economic development models of specific countries or regions. Of foremost importance is the need for governments to carefully balance economic and public health policies when considering liberalisation

Vibrations and Berry Phases of Charged Buckminsterfullerene

A simple model of electron-vibron interactions in buckminsterfullerene ions is solved semiclassically. Electronic degeneracies of C$_{60}$$^{n-}$ induce dynamical Jahn-Teller distortions, which are unimodal for $n\!\ne\!3$ and bimodal for $n\!=\!3$. The quantization of motion along the Jahn-Teller manifold leads to a symmetric-top rotator Hamiltonian. I find Molecular Aharonov-Bohm effects where electronic Berry phases determine the vibrational spectra, zero point fluctuations, and electrons' pair binding energies. The latter are relevant to superconductivity in alkali-fullerenes.Comment: Latex 11 pages. IIT-00

Phthalazinone inhibitors of inosine-5?-monophosphate dehydrogenase from Cryptosporidium parvum

Cryptosporidium parvum (Cp) is a potential biowarfare agent and major cause of diarrhea and malnutrition. This protozoan parasite relies on inosine 5?-monophosphate dehydrogenase (IMPDH) for the production of guanine nucleotides. A CpIMPDH-selective N-aryl-3,4-dihydro-3-methyl-4-oxo-1-phthalazineacetamide inhibitor was previously identified in a high throughput screening campaign. Herein we report a structure–activity relationship study for the phthalazinone-based series that resulted in the discovery of benzofuranamide analogs that exhibit low nanomolar inhibition of CpIMPDH. In addition, the antiparasitic activity of select analogs in a Toxoplasma gondii model of C. parvum infection is also presented

Parent-only interventions for childhood overweight or obesity in children aged 5 to 11 years

Background: Child and adolescent overweight and obesity have increased globally, and are associated with short- and long-term health consequences.Objectives: To assess the efficacy of diet, physical activity and behavioural interventions delivered to parents only for the treatment of overweight and obesity in children aged 5 to 11 years.Search methods: We performed a systematic literature search of databases including the Cochrane Library,MEDLINE, EMBASE, PsycINFO, CINAHL and LILACS as well trial registers.We checked references of identified trials and systematic reviews.We applied no language restrictions. The date of the last search was March 2015 for all databases.Selection criteria: We selected randomised controlled trials (RCTs) of diet, physical activity and behavioural interventions delivered to parents only for treating overweight or obesity in children aged 5 to 11 years.Data collection and analysis: Two review authors independently assessed trials for risk of bias and evaluated overall study quality using the GRADE instrument. Where necessary, we contacted authors for additional information.Main results: We included 20 RCTs, including 3057 participants. The number of participants ranged per trial between 15 and 645. Follow-up ranged between 24 weeks and two years. Eighteen trials were parallel RCTs and two were cluster RCTs. Twelve RCTs had two comparisons and eight RCTs had three comparisons. The interventions varied widely; the duration, content, delivery and follow-up of the interventions were heterogeneous. The comparators also differed. This review categorised the comparisons into four groups: parent-only versus parent-child, parent-only versus waiting list controls, parent-only versus minimal contact interventions and parent-only versus other parent-only interventions. Trial quality was generally low with a large proportion of trials rated as high risk of bias on individual risk of bias criteria. In trials comparing a parent-only intervention with a parent-child intervention, the body mass index (BMI) z score change showed a mean difference (MD) at the longest follow-up period (10 to 24 months) of -0.04 (95% confidence interval (CI) -0.15 to 0.08); P = 0.56; 267 participants; 3 trials; low quality evidence. In trials comparing a parent-only intervention with a waiting list control, the BMI z score change in favour of the parent-only intervention at the longest follow-up period (10-12 months) had an MD of -0.10 (95% CI -0.19 to -0.01); P = 0.04; 136 participants; 2 trials; low quality evidence. BMI z score change of parent-only interventions when compared with minimal contact control interventions at the longest follow-up period (9 to 12 months) showed an MD of 0.01 (95% CI -0.07 to 0.09); P = 0.81; 165 participants; 1 trial; low quality evidence. There were few similarities between interventions and comparators across the included trials in the parent-only intervention versus other parent-only interventions and we did not pool these data. Generally, these trials did not show substantial differences between their respective parent-only groups on BMI outcomes. Other outcomes such as behavioural measures, parent-child relationships and health-related quality of life were reported inconsistently. Adverse effects of the interventions were generally not reported, two trials stated that there were no serious adverse effects. No trials reported on all-cause mortality, morbidity or socioeconomic effects. All results need to be interpreted cautiously because of their low quality, the heterogeneous interventions and comparators, and the high rates of non-completion.Authors’ conclusions: Parent-only interventions may be an effective treatment option for overweight or obese children aged 5 to 11 years when compared with waiting list controls. Parent-only interventions had similar effects compared with parent-child interventions and compared with those with minimal contact controls. However, the evidence is at present limited; some of the trials had a high risk of bias with loss to follow-up being a particular issue and there was a lack of evidence for several important outcomes. The systematic review has identified 10 ongoing trials that have a parent-only arm, which will contribute to future updates. These trials will improve the robustness of the analyses by type of comparator, and may permit subgroup analysis by intervention component and the setting. Trial reports should provide adequate details about the interventions to be replicated by others. There is a need to conduct and report cost effectiveness analyses in future trials in order to establish whether parent-only interventions are more cost-effective than parent-child interventions

Electron--Vibron Interactions and Berry Phases in Charged Buckminsterfullerene: Part I

A simple model for electron-vibron interactions on charged buckminsterfullerene C$_{60}^{n-}$, $n=1,\ldots 5$, is solved both at weak and strong couplings. We consider a single $H_g$ vibrational multiplet interacting with $t_{1u}$ electrons. At strong coupling the semiclassical dynamical Jahn-Teller theory is valid. The Jahn-Teller distortions are unimodal for $n$=1,2,4,5 electrons, and bimodal for 3 electrons. The distortions are quantized as rigid body pseudo--rotators which are subject to geometrical Berry phases. These impose ground state degeneracies and dramatically change zero point energies. Exact diagonalization shows that the semiclassical level degeneracies and ordering survive well into the weak coupling regime. At weak coupling, we discover an enhancement factor of $5/2$ for the pair binding energies over their classical values. This has potentially important implications for superconductivity in fullerides, and demonstrates the shortcoming of Migdal--Eliashberg theory for molecular crystals.Comment: 29 pages (+7 figures, 3 available upon request), LATEX, report-number: BM515