Unconventional superconductivity in the cage type compound Sc5_5Rh6_6Sn18_{18}

We have examined the superconducting ground state properties of the caged type compound Sc$_5$Rh$_6$Sn$_{18}$ using magnetization, heat capacity, and muon-spin relaxation or rotation ($\mu$SR) measurements. Magnetization measurements indicate type-II superconductivity with an upper critical field $\mu_0H_{c2}(0)$ = 7.24 T. The zero-field cooled and field cooled susceptibility measurements unveil an onset of diamagnetic signal below $T_{\bf c}$ = 4.4 K. The interpretation of the heat capacity results below $T_{\bf c}$ using the $\alpha-$BCS model unveils the value of $\alpha$ = 2.65, which gives the dimensionless ratio 2$\Delta(0)/k_B T_{\bf c}$ = 5.3, intimating that Sc$_5$Rh$_6$Sn$_{18}$ is a strong-coupling BCS superconductor. The zero-field $\mu$SR measurements in the longitudinal geometry exhibit a signature of a spontaneous appearance of the internal magnetic field below the superconducting transition temperature, indicating that the superconducting state is characterized by the broken time-reversal symmetry (TRS). We have compared the results of broken TRS in Sc$_5$Rh$_6$Sn$_{18}$ with that observed in R$_5$Rh$_6$Sn$_{18}$ (R = Lu and Y).Comment: 6 pages, 4 figures. arXiv admin note: text overlap with arXiv:1411.687

Standards Based Social Emotional Learning for Students with Autism Spectrum Disorder

This study investigates how professionals in the field perceive the usefulness of the Kase-Roberts Curriculum for Social Emotional Learning for Students with Autism. The study included 176 participants from divisions of the Council for Exceptional Children. Most of the participants had over 10 years of teaching experience (M= 13.42, SD= 1.6) which helped to increase the credibly of overall survey responses. Data was collected through a Likert scale online survey created by SurveyMonkeyTM and analysis of survey items were carried out. Results of the survey revealed that a total of 172 (98.29 %) participants are interested in the Kase-Roberts Curriculum and also showed that 7 (4.00%) of participants selected Disagree when asked, “I believe it is part of the teacher\u27s job to teach children how to manage distress and other upsetting feelings”, indicating that the majority of educators perceive that it is the teachers responsibility to teach students how to manage distress and other upsetting feelings. The Kase-Roberts curriculum was developed to provide educators with a meaningful resource to address the social emotional needs of students with Autism while also meeting state standards for academic instruction in literacy

Broken time-reversal symmetry probed by muon spin relaxation in the caged type superconductor Lu5Rh6Sn18

The superconducting state of the caged type compound Lu5Rh6Sn18 has been investigated by using magnetization, heat capacity, and muon spin relaxation or rotation (?SR) measurements, and the results interpreted on the basis of the group theoretical classifications of the possible pairing symmetries and a simple model of the resulting quasiparticle spectra. Our zero-field ?SR measurements clearly reveal the spontaneous appearance of an internal magnetic field below the transition temperature, which indicates that the superconducting state in this material is characterized by broken time-reversal symmetry. Further, the analysis of the temperature dependence of the magnetic penetration depth measured using the transverse-field ?SR measurements suggests an isotropic s?wave character for the superconducting gap. This is in agreement with the heat capacity behavior, and we show that it can be interpreted in terms of a nonunitary triplet state with point nodes and an open Fermi surface

Investigation of Superconducting Gap Structure in HfIrSi using muon spin relaxation/rotation

Appearance of strong spin-orbit coupling (SOC) is apparent in ternary equiatomic compounds with 5$d$-electrons due to the large atomic radii of transition metals. SOC plays a significant role in the emergence of unconventional superconductivity. Here we examined the superconducting state of HfIrSi using magnetization, specific heat, zero and transverse-field (ZF/TF) muon spin relaxation/rotation ($\mu$SR) measurements. Superconductivity is observed at $T_\mathrm{C}$ = 3.6 K as revealed by specific heat and magnetization measurements. From the TF$-\mu$SR analysis it is clear that superfluid density well described by an isotropic BCS type $s$-wave gap structure. Furthermore, from TF$-\mu$SR data we have also estimated the superconducting carrier density $n_\mathrm{s}$ = 6.6 $\times$10$^{26}$m$^{-3}$, London penetration depth $\lambda_{L}(0)$ = 259.59 nm and effective mass $m^{*}$ = 1.57 $m_{e}$. Our zero-field muon spin relaxation data indicate no clear sign of spontaneous internal field below $T_\mathrm{C}$, which implies that the time-reversal symmetry is preserved in HfIrSi. Theoretical investigation suggests Hf and Ir atoms hybridize strongly along the $c$-axis of the lattice, which is responsible for the strong three-dimensionality of this system which screens the Coulomb interaction. As a result despite the presence of correlated $d$-electrons in this system, the correlation effect is weakened, promoting electron-phonon coupling to gain importance.Comment: 8 pages, 4 figure

Probing the superconducting ground state of ZrIrSi: A μ\muSR study

The superconducting ground state of newly reported ZrIrSi is probed by means of $\mu$SR technique along with resistivity measurement. The occurrence of superconductivity at $T_\mathrm{C}$ = 1.7 K is confirmed by resistivity measurement. ZF-$\mu$SR study revealed that below $T_\mathrm{C}$, there is no spontaneous magnetic field in the superconducting state, indicates TRS is preserved in case of ZrIrSi. From TF-$\mu$SR measurement, we have estimated the superfluid density as a function of temperature, which is described by an isotropic $s-$wave model with a superconducting gap $2\Delta(0)/k_\mathrm{B}T_\mathrm{C}$ = 5.1, indicates the presence of strong spin-orbit coupling. {\it Ab-initio} electronic structure calculation indicates that there are four bands passing through the Fermi level, forming four Fermi surface pockets. We find that the low-energy bands are dominated by the $4d$-orbitals of transition metal Zr, with substantially lesser weight from the $5d$-orbitals of the Ir-atoms.Comment: 6 pages, 4 figure

Effects of Inducing Post Activation Potentiation on Leg Extensors using Isotonic Movements

Post Activation Potentiation (PAP) has been documented in previous studies as evoking greater muscle activation and velocities in submaximal contractions. Literature has additionally shown that isotonic contractions have increased motor unit activation when compared to isokinetic. PURPOSE: Induce PAP using different interventions and evaluate PAP differences between interventions in the vastus lateralis (VL), rectus femoris (RF), vastus medialis (VM) and evaluate velocity and muscle activation differences. METHODS: 8 recreationally active males (n=8, age = 20.6 ± 1.8, height = 178.2 ± 12.1 cm, weight = 83.2 ± 48.3 kg) with no previous lower extremity injuries completed this study. Following a familiarization visit, subjects completed three randomized visits separated by 24 hours. Each visit consisted of one of the following interventions to induce PAP: 2 sets of 6 isotonic leg extensions at 50% MVC, 4 isometric MVCs, or two sets of 6 isotonic extensions at 60% MVC. Following each intervention subjects performed 20 isotonic knee extensions at 30% MVC. Peak velocity was recorded during these contractions in the familiarization day as well as subsequent visits using a robotic dynamometer (Biodex System 4). Three 4-pin Surface electromyography (EMG) sensors were placed over the VL, RF, and VM to record muscle activation. After collecting EMG signals root mean square (RMS) values were calculated for each muscle. 3 separate one-way analyses of variance (ANOVA) were completed to compare RMS values for each muscle across each visit. 1 separate one-way ANOVA was run to compare peak velocity across each visit. A 2-way repeated measures ANOVA (Muscle [VL v RF v VM] x Intervention [2 sets of 6 isotonic contractions at 50% MVC v four isometric MVCs v 2 sets of 6 isotonic contractions at 60% MVC]) was used to compare RMS values across visits. RESULTS: There were no significant differences (p\u3e0.05) in RMS values the VL, or the RF across visits in the one-way ANOVAs comparing muscular differences. The one-way ANOVA for peak velocity also showed no significant differences across visits (p\u3e.05). However, a main effect was found between visits in the VM (p =.014). CONCLUSION: PAP intervention has been shown in previous studies to increase velocity; however, this was not found to a significant effect. A larger sample size could result in this being induced to a larger degree. Additionally, intrasubject differences could also have contributed. The VM having increased activation between visits may be caused by PAP evoking a larger response in this muscle compared to the other leg extensors. Further research should be performed to examine these findings. Additionally, motor unit behavior analysis could reveal additional differences between the interventions and the effects on each of the leg extensors

Genetic Correlates of Brain Aging on MRI and Cognitive Test Measures: A Genome-Wide Association and Linkage Analysis in the Framingham Study

BACKGROUND: Brain magnetic resonance imaging (MRI) and cognitive tests can identify heritable endophenotypes associated with an increased risk of developing stroke, dementia and Alzheimer's disease (AD). We conducted a genome-wide association (GWA) and linkage analysis exploring the genetic basis of these endophenotypes in a community-based sample. METHODS: A total of 705 stroke- and dementia-free Framingham participants (age 62 +9 yrs, 50% male) who underwent volumetric brain MRI and cognitive testing (1999–2002) were genotyped. We used linear models adjusting for first degree relationships via generalized estimating equations (GEE) and family based association tests (FBAT) in additive models to relate qualifying single nucleotide polymorphisms (SNPs, 70,987 autosomal on Affymetrix 100K Human Gene Chip with minor allele frequency ≥ 0.10, genotypic call rate ≥ 0.80, and Hardy-Weinberg equilibrium p-value ≥ 0.001) to multivariable-adjusted residuals of 9 MRI measures including total cerebral brain (TCBV), lobar, ventricular and white matter hyperintensity (WMH) volumes, and 6 cognitive factors/tests assessing verbal and visuospatial memory, visual scanning and motor speed, reading, abstract reasoning and naming. We determined multipoint identity-by-descent utilizing 10,592 informative SNPs and 613 short tandem repeats and used variance component analyses to compute LOD scores. RESULTS: The strongest gene-phenotype association in FBAT analyses was between SORL1 (rs1131497; p = 3.2 × 10-6) and abstract reasoning, and in GEE analyses between CDH4 (rs1970546; p = 3.7 × 10-8) and TCBV. SORL1 plays a role in amyloid precursor protein processing and has been associated with the risk of AD. Among the 50 strongest associations (25 each by GEE and FBAT) were other biologically interesting genes. Polymorphisms within 28 of 163 candidate genes for stroke, AD and memory impairment were associated with the endophenotypes studied at p < 0.001. We confirmed our previously reported linkage of WMH on chromosome 4 and describe linkage of reading performance to a marker on chromosome 18 (GATA11A06), previously linked to dyslexia (LOD scores = 2.2 and 5.1). CONCLUSION: Our results suggest that genes associated with clinical neurological disease also have detectable effects on subclinical phenotypes. These hypothesis generating data illustrate the use of an unbiased approach to discover novel pathways that may be involved in brain aging, and could be used to replicate observations made in other studies.National Institutes of Health National Center for Research Resources Shared Instrumentation grant (ISI0RR163736-01A1); National Heart, Lung, and Blood Institute's Framingham Heart Study (N01-HC-25195); National Institute of Aging (5R01-AG08122, 5R01-AG16495); National Institute of Neurological Disorders and Stroke (5R01-NS17950

Regional Motor Unit Firing Behaviors of Mono- and Bi-Articular Leg Extensor Muscles

Motor unit (MU) activation patterns provide vast insight into skeletal muscle contractions and may differ depending on architectural differences. Previous findings have suggested that MU activation patterns, specifically within the quadriceps group, are region-specific; this, along with the architectural differences between the quadriceps muscles, may further influence force production as reflected within the relationships between the firings. PURPOSE: To examine regional activation in proximal and distal regions of biarticular [rectus femoris (RF)] and monoarticular [vastus lateralis (VL)] knee extensors during submaximal isometric knee extensions. METHODS: On two separate randomized visits, eight lower-body resistance trained individuals, 6 males (n=6, age= 25.2 ±3.77) and 2 females (n=2, age= 21 ±1.4), performed submaximal isometric contractions at 30% and 70% of their maximal voluntary contractions (MVC) in a custom-built seat using an S-beam load-cell. Two separate 5-pin surface electromyography (EMG) sensors were used to record activation in the proximal and distal locations of either the VL or RF. Signals were recorded and decomposed into their constituent motor unit action potential (MUAP) trains, validated, and assessed for relative behavioral properties. For subsequent analysis of firing behaviors, the relationships (Slopes and intercepts) between motor unit action potential size (MUAPsize,) recruitment threshold (RT%), and mean firing rate (MFR) were calculated. Twelve separate two-way repeated measures analyses of variance (ANOVA) (location [proximal v distal] x muscle [VL v RF]) were used to compare slopes and intercepts of MFR vs. RT%, MUAPsize vs. RT%, and MFR vs. MUAPsize at both 30% and 70% MVC. RESULTS: There was a significant location x muscle interaction in the MFR v MUAPsize slopes during 30% MVC contraction (pCONCLUSION: The location by muscle interaction in the MFR v MUAPsize slopes during 30% MVC may indicate muscle fiber type distribution differences between sensor locations specifically, more type II fibers in the distal location of the VL

Perturbation theory of the space-time non-commutative real scalar field theories

The perturbative framework of the space-time non-commutative real scalar field theory is formulated, based on the unitary S-matrix. Unitarity of the S-matrix is explicitly checked order by order using the Heisenberg picture of Lagrangian formalism of the second quantized operators, with the emphasis of the so-called minimal realization of the time-ordering step function and of the importance of the $\star$-time ordering. The Feynman rule is established and is presented using $\phi^4$ scalar field theory. It is shown that the divergence structure of space-time non-commutative theory is the same as the one of space-space non-commutative theory, while there is no UV-IR mixing problem in this space-time non-commutative theory.Comment: Latex 26 pages, notations modified, add reference

Time Course Change of Muscle Thickness of the Tibialis Anterior Following Blood Flow Restricted Training

Traditional resistance training programs recommend training loads of at least 60% 1-repetition maximum (1RM) to stimulate muscle hypertrophy within 3 weeks. Low-load blood flow restricted (BFR) resistance training (RT) has implications in rehabilitation since this modality has shown comparable muscle hypertrophy to high-load RT at intensities as low as 30% 1RM. However, the recommended effects of BFR on muscle size in various musculature throughout an intervention has not been thoroughly examined. PURPOSE: Therefore, the purpose of this investigation is to measure temporal changes in muscle thickness (MT) on the tibialis anterior (TA) throughout 4 weeks of BFR training. METHODS: Thirteen untrained participants were randomized into two groups: (BFR; n=8) (177.6 ± 4.1 cm, 84.8 ± 15.1 kg, 21.3 ± 1 years) or control non-BFR (n=5) (172.6 ± 8.2 cm, 76.7 ± 11.1 kg, 23.4 ± 2.7 years) who were matched for training sessions, sets, and reps. During the 4-week period (8 sessions), participants underwent twice-weekly sessions of unilateral isokinetic dorsiflexion training at 30% of their daily peak torque at a velocity of 60°/s with or without BFR. Ultrasound-derived measures of muscle thickness were captured at one-third the distance from the fibular head to the medial malleolus prior to the pre- and post-intervention testing sessions. Two separate linear regression analyses were used to examine group slope differences in MT across all training sessions. RESULTS: Linear regression analyses indicated that the control (i.e., non-BFR) exhibited a significant, positive (b = 0.023, SE = 0.01, r2=0.626, p=0.006) increase in MT from pre- to post testing. However, there was no significant change (b=0.021, SE = 0.01, r2=0.324, p=0.086) in MT across Time for the BFR group. CONCLUSION: Low-load RT without BFR induces temporal changes in muscle size following a short 4-week intervention. This exemplifies the efficacy of low-load training in inducing detectible changes in muscle thickness of the TA, and does not indicate BFR has an additive effect on temporal changes in muscle size of novice males following a 4-week intervention