From Large to Small Scales: Global Models of the ISM

We review large scale modelling of the ISM with emphasis on the importance to include the disk-halo-disk duty cycle and to use a dynamical refinement of the grid (in regions where steep variations of density and pressure occur) for a realistic modelling of the ISM. We also discuss the necessity of convergence of the simulation results by comparing 0.625, 1.25 and 2.5 pc resolution simulations and show that a minimum grid resolution of 1.25 pc is required for quantitatively reliable results, as there is a rapid convergence for Delta x \leq 1.1 pc.Comment: 10 pages, 8 figures that include 2 simulation images (in jpeg format) and 6 plots (4 in ps and 2 in jpeg formats), to appear in the proceedings of ``From Observations to Self-Consistent Modelling of the ISM in Galaxies'', Kluwe

The Erosion Properties of Chlorine Dioxide and Hydrogen Peroxide on Bovine Teeth

Objectives: The aim of this study was to assess the erosion potential of chlorine dioxide and hydrogen peroxide on bovine teeth. Methods: Sixty bovine crowns were ground and polished to give flat surfaces. The crowns were subjected to heavy staining cycles then equally divided into 3 treatment groups; chlorine dioxide (ClO2), hydrogen peroxide (H2O2), and deionised water (H2O). Specimens in each group were immersed in 150 ml of the treatment for seven 2 min cycle in addition to an extra 30 min cycle. Specimens were gently dried after each 2 min cycle to take quantitative light-induced fluorescence (QLF) images while non- contact light profilometry (NCLP) scans were performed at the end of the seven 2 min and the extra 30 min cycles. Results: ClO2 specimens showed a significant increase in %ΔF only after the first 2 min cycle (p < 0.05); however, a significant increase in %ΔF within H2O2 specimens was found at the end of the seven recommended treatment cycles (p < 0.05). Conclusion: Chlorine dioxide does cause enamel erosion but to a lesser extent than that caused by hydrogen peroxide

Cortical and Subcortical Effects of Transcutaneous Spinal Cord Stimulation in Humans with Tetraplegia.

An increasing number of studies supports the view that transcutaneous electrical stimulation of the spinal cord (TESS) promotes functional recovery in humans with spinal cord injury (SCI). However, the neural mechanisms contributing to these effects remain poorly understood. Here we examined motor-evoked potentials in arm muscles elicited by cortical and subcortical stimulation of corticospinal axons before and after 20 min of TESS (30 Hz pulses with a 5 kHz carrier frequency) and sham-TESS applied between C5 and C6 spinous processes in males and females with and without chronic incomplete cervical SCI. The amplitude of subcortical, but not cortical, motor-evoked potentials increased in proximal and distal arm muscles for 75 min after TESS, but not sham-TESS, in control subjects and SCI participants, suggesting a subcortical origin for these effects. Intracortical inhibition, elicited by paired stimuli, increased after TESS in both groups. When TESS was applied without the 5 kHz carrier frequency both subcortical and cortical motor-evoked potentials were facilitated without changing intracortical inhibition, suggesting that the 5 kHz carrier frequency contributed to the cortical inhibitory effects. Hand and arm function improved largely when TESS was used with, compared with without, the 5 kHz carrier frequency. These novel observations demonstrate that TESS influences cortical and spinal networks, having an excitatory effect at the spinal level and an inhibitory effect at the cortical level. We hypothesized that these parallel effects contribute to further the recovery of limb function following SCI.SIGNIFICANCE STATEMENT Accumulating evidence supports the view that transcutaneous electrical stimulation of the spinal cord (TESS) promotes recovery of function in humans with spinal cord injury (SCI). Here, we show that a single session of TESS over the cervical spinal cord in individuals with incomplete chronic cervical SCI influenced in parallel the excitability cortical and spinal networks, having an excitatory effect at the spinal level and an inhibitory effect at the cortical level. Importantly, these parallel physiological effects had an impact on the magnitude of improvements in voluntary motor output

Fatigue analysis-based numerical design of stamping tools made of cast iron

This work concerns stress and fatigue analysis of stamping tools made of cast iron with an essentially pearlitic matrix and containing foundry defects. Our approach consists at first, in coupling the stamping numerical processing simulations and structure analysis in order to improve the tool stiffness geometry for minimizing the stress state and optimizing their fatigue lifetime. The method consists in simulating the stamping process by considering the tool as a perfect rigid body. The estimated contact pressure is then used as boundary condition for FEM structure loading analysis of the tool. The result of this analysis is compared with the critical stress limit depending on the automotive model. The acceptance of this test allows calculating the fatigue lifetime of the critical zone by using the S–N curve of corresponding load ratio. If the prescribed tool life requirements are not satisfied, then the critical region of the tool is redesigned and the whole simulation procedures are reactivated. This method is applied for a cast iron EN-GJS-600-3. The stress-failure (S–N) curves for this material is determined at room temperature under push pull loading with different load ratios R0σmin/σmax0−2, R0−1 and R00.1. The effects of the foundry defects are determined by SEM observations of crack initiation sites. Their presence in tested specimens is associated with a reduction of fatigue lifetime by a factor of 2. However, the effect of the load ratio is more important

Salvage rates and prognostic factors after relapse in children and adolescents with initially localised synovial sarcoma

Background: Previous studies have reported a poor outcome for synovial sarcoma patients whose tumours relapse. Methods: This study analysed 44 relapsing cases in a series of 118 consecutive patients&lt;21 yr of age with non-metastatic synovial sarcoma prospectively enrolled in Italian paediatric protocols between 1979 and 2006. In an effort to identify a possible risk-adapted stratification enabling a better planning of second-line treatment, the relapsing patients' outcome was analysed vis-à-vis their clinical picture at onset, first-line treatments, clinical findings at the time of first relapse and second-line treatment modalities. Results: The first event was a local recurrence in only 15 cases, and metastatic in 29 (associated with local relapse too in 7 cases). The time to relapse ranged from 4 to 108 months (median 20 months). Overall survival was 29.7% and 21.0% five and ten years after relapsing, respectively. The variables influencing survival were the timing and type of relapse (combined) and the chances of a secondary remission, which correlated strongly with the feasibility of complete surgery. Conclusions: Our study confirmed a largely unsatisfactory prognosis after recurrences in children and adolescents with synovial sarcoma: the chances of survival can be estimated on the basis of several variables for the purposes of planning risk-adapted salvage protocols. An aggressive surgical approach should be recommended. New effective systemic agents are warranted, and experimental therapies can be offered to patients with little chance of salvage. © 2012 Elsevier Ltd. All rights reserved

Local structure study of the orbital order/disorder transition in LaMnO3

We use a combination of neutron and X-ray total scattering measurements together with pair distribution function (PDF) analysis to characterise the variation in local structure across the orbital order--disorder transition in LaMnO$_3$. Our experimental data are inconsistent with a conventional order--disorder description of the transition, and reflect instead the existence of a discontinuous change in local structure between ordered and disordered states. Within the orbital-ordered regime, the neutron and X-ray PDFs are best described by a local structure model with the same local orbital arrangements as those observed in the average (long-range) crystal structure. We show that a variety of meaningfully-different local orbital arrangement models can give fits of comparable quality to the experimental PDFs collected within the disordered regime; nevertheless, our data show a subtle but consistent preference for the anisotropic Potts model proposed in \emph{Phys Rev.\ B} {\bf 79}, 174106 (2009). The key implications of this model are electronic and magnetic isotropy together with the loss of local inversion symmetry at the Mn site. We conclude with a critical assessment of the interpretation of PDF measurements when characterising local symmetry breaking in functional materials.Comment: 14 pages, 8 figures, 3 table

High-efficiency fullerene solar cells enabled by a spontaneously formed mesostructured CuSCN-nanowire heterointerface

Fullerenes and their derivatives are widely used as electron acceptors in bulk-heterojunction organic solar cells as they combine high electron mobility with good solubility and miscibility with relevant semiconducting polymers. However, studies on the use of fullerenes as the sole photogeneration and charge-carrier material are scarce. Here, a new type of solution-processed small-molecule solar cell based on the two most commonly used methanofullerenes, namely [6,6]-phenyl-C61-butyric acid methyl ester (PC 60 BM) and [6,6]-phenyl-C71-butyric acid methyl ester (PC 70 BM), as the light absorbing materials, is reported. First, it is shown that both fullerene derivatives exhibit excellent ambipolar charge transport with balanced hole and electron mobilities. When the two derivatives are spin-coated over the wide bandgap p-type semiconductor copper (I) thiocyanate (CuSCN), cells with power conversion efficiency (PCE) of ≈1%, are obtained. Blending the CuSCN with PC 70 BM is shown to increase the performance further yielding cells with an open-circuit voltage of ≈0.93 V and a PCE of 5.4%. Microstructural analysis reveals that the key to this success is the spontaneous formation of a unique mesostructured p-n-like heterointerface between CuSCN and PC 70 BM. The findings pave the way to an exciting new class of single photoactive material based solar cells

Primary psoas abscess extending to thigh adductors: case report

<p>Abstract</p> <p>Background</p> <p>Psoas abscess is a rare condition consisting of pyomyositis of the psoas. The worldwide incidence was 12 cases per 100,000 per year in 1992, but the current incidence is unknown. Psoas abscess can descend along the psoas sheath and reach the inner upper third of the thigh, but only infrequently does it penetrate the sheath and involve the thigh adductors. Because of insidious clinical presentation, the diagnosis of psoas abscess is a challenge. Delayed diagnosis can result in poor prognosis.</p> <p>Case presentation</p> <p>A 45-year-old male with no significant past medical history presented with pain in the left thigh, and limitation of movement at the left hip and knee joint for one month. Ultrasound, CT, and MRI revealed a liquid mass in the left psoas. Percutaneous drainage of this mass yielded 300 ml pus from the psoas. After surgery, the patient reported relief of pain; however, ten days after removal of the drainage tube, the patient complained of persistent pain in his left thigh. CT revealed that the psoas abscess had extended inferiorly, and involved the entire set of adductors of the left thigh. Open surgical drainage was performed at the flank and at the thigh, yielding 350 ml of pus from the thigh. After open drainage and adequate antibiotic therapy, the patient made a good recovery. Follow-up CT confirmed complete resolution of the abscess.</p> <p>Conclusions</p> <p>Large psoas abscess can penetrate the psoas sheath, and descend to thigh adductors even after percutaneous drainage. Appropriate treatment includes open surgical drainage along with antibiotic therapy.</p

When Anomaly Mediation is UV Sensitive

Despite its successes---such as solving the supersymmetric flavor problem---anomaly mediated supersymmetry breaking is untenable because of its prediction of tachyonic sleptons. An appealing solution to this problem was proposed by Pomarol and Rattazzi where a threshold controlled by a light field deflects the anomaly mediated supersymmetry breaking trajectory, thus evading tachyonic sleptons. In this paper we examine an alternate class of deflection models where the non-supersymmetric threshold is accompanied by a heavy, instead of light, singlet. The low energy form of this model is the so-called extended anomaly mediation proposed by Nelson and Weiner, but with potential for a much higher deflection threshold. The existence of this high deflection threshold implies that the space of anomaly mediated supersymmetry breaking deflecting models is larger than previously thought.Comment: 14 pages, 1 figure (version to appear in JHEP