9,388 research outputs found

    Apparatus for cutting elastomeric materials

    Get PDF
    Sharp thin cutting edge is held in head of milling machine designed for metal working. Controls of machine are used to position cutting edge in same plane as vibrating specimen. Controls then are operated, making blade come into contact with specimen, to cut it into shapes and sizes desired. Cut surfaces appear mirror-smooth; vibrating mechanism causes no visible striations

    Barefoot running improves economy at high intensities and peak treadmill velocity

    Get PDF
    Aim: Barefoot running can improve running economy (RE) compared to shod running at low exercise intensities, but data is lacking for the higher intensities typical during many distance running competitions. The influence of barefoot running on the velocity at maximal oxygen uptake (vVO2max) and peak incremental treadmill test velocity (vmax) is unknown. The present study tested the hypotheses that barefoot running would improve RE, vVO2max and vmax relative to shod running. Methods: Using a balanced within-subject repeated measures design, eight male runners (aged 23.1Ā±4.5 years, height 1.80Ā±0.06 m, mass 73.8Ā±11.5 kg, VO2max 4.08Ā±0.39 LĀ·min-1) completed a familiarization followed by one barefoot and one shod treadmill running trial, 2-14 days apart. Trial sessions consisted of a 5 minute warm-up, 5 minute rest, followed by 4Ɨ4 minute stages, at speeds corresponding to ~67, 75, 84 and 91% shod VO2max respectively, separated by a 1 minute rest. After the 4th stage treadmill speed was incremented by 0.1 kmĀ·h-1 every 15 s until participants reached volitional exhaustion. Results: RE was improved by 4.4Ā±7.0% across intensities in the barefoot condition (P=0.040). The improvement in RE was related to removed shoe mass (r2=0.80, P=0.003) with an intercept at 0% improvement for RE at 0.520 kg total shoe mass. Both vVO2max (by 4.5Ā±5.0%, P=0.048) and vmax (by 3.9Ā±4.0%, P=0.030) also improved but VO2max was unchanged (p=0.747). Conclusion: Barefoot running improves RE at high exercise intensities and increases vVO2max and vmax, but further research is required to clarify the influence of very light shoe weights on RE

    Conformational dynamics of the Hop1 HORMA domain reveal a common mechanism with the spindle checkpoint protein Mad2.

    Get PDF
    The HORMA domain is a highly conserved protein-protein interaction module found in eukaryotic signaling proteins including the spindle assembly checkpoint protein Mad2 and the meiotic HORMAD proteins. HORMA domain proteins interact with short 'closure motifs' in partner proteins by wrapping their C-terminal 'safety belt' region entirely around these motifs, forming topologically-closed complexes. Closure motif binding and release requires large-scale conformational changes in the HORMA domain, but such changes have only been observed in Mad2. Here, we show that Saccharomyces cerevisiae Hop1, a master regulator of meiotic recombination, possesses conformational dynamics similar to Mad2. We identify closure motifs in the Hop1 binding partner Red1 and in Hop1 itself, revealing that HORMA domain-closure motif interactions underlie both Hop1's initial recruitment to the chromosome axis and its self-assembly on the axis. We further show that Hop1 adopts two distinct folded states in solution, one corresponding to the previously-observed 'closed' conformation, and a second more extended state in which the safety belt region has disengaged from the HORMA domain core. These data reveal strong mechanistic similarities between meiotic HORMADs and Mad2, and provide a mechanistic basis for understanding both meiotic chromosome axis assembly and its remodeling by the AAA+ ATPase Pch2/TRIP13

    Regulating Compensation for Injuries Associated with Medical Error

    Full text link
    Tort-based system of compensation for injuries associated with medical error is inadequate - development of innovative approaches to no-fault compensation - proposed model of compensation based on the idea of institutions integrating rights-to-claim compensation with regulatory strategies to improve patient safety

    Galaxy Clusters Selected via the Sunyaevā€“Zel'dovich Effect in the SPTpol 100-square-degree Survey

    Get PDF
    We present a catalog of galaxy cluster candidates detected in 100 square degrees surveyed with the SPTpol receiver on the South Pole Telescope. The catalog contains 89 candidates detected with a signal-to-noise ratio greater than 4.6. The candidates are selected using the Sunyaevā€“Zel'dovich effect at 95 and 150 GHz. Using both space- and ground-based optical and infrared telescopes, we have confirmed 81 candidates as galaxy clusters. We use these follow-up images and archival images to estimate photometric redshifts for 66 galaxy clusters and spectroscopic observations to obtain redshifts for 13 systems. An additional two galaxy clusters are confirmed using the overdensity of near-infrared galaxies only and are presented without redshifts. We find that 15 candidates (18% of the total sample) are at redshift z ā‰„ 1.0, with a maximum confirmed redshift of z_(max) = 1.38Ā±0.10. We expect this catalog to contain every galaxy cluster with M_(500c) > 2.6Ɨ10Ā¹ā“MāŠ™hā»Ā¹ā‚‡ā‚€ and z > 0.25 in the survey area. The mass threshold is approximately constant above z = 0.25, and the complete catalog has a median mass of approximately M_(500c) > 2.7Ɨ10Ā¹ā“MāŠ™hā»Ā¹ā‚‡ā‚€. Compared to previous SPT works, the increased depth of the millimeter-wave data (11.2 and 6.5 Ī¼K-arcmin at 95 and 150 GHz, respectively) makes it possible to find more galaxy clusters at high redshift and lower mass

    Constraints on Cosmological Parameters from the 500 degĀ² SPTPOL Lensing Power Spectrum

    Get PDF
    We present cosmological constraints based on the cosmic microwave background (CMB) lensing potential power spectrum measurement from the recent 500 degĀ² SPTPOL survey, the most precise CMB lensing measurement from the ground to date. We fit a flat Ī›CDM model to the reconstructed lensing power spectrum alone and in addition with other data sets: baryon acoustic oscillations (BAO), as well as primary CMB spectra from Planck and SPTPOL. The cosmological constraints based on SPTPOL and Planck lensing band powers are in good agreement when analyzed alone and in combination with Planck full-sky primary CMB data. With weak priors on the baryon density and other parameters, the SPTPOL CMB lensing data alone provide a 4% constraint on Ļƒā‚ˆĪ©^(0.25)_m = 0.593 Ā± 0.025. Jointly fitting with BAO data, we find Ļƒā‚ˆ = 0.779Ā±0.023, Ī©_m = 0.368^(+0.032)_(āˆ’0.037), and Hā‚€ = 72.0^(+2.1)_(āˆ’2.5)kmsā»Ā¹ Mpcā»Ā¹, up to 2Ļƒ away from the central values preferred by Planck lensing + BAO. However, we recover good agreement between SPTPOL and Planck when restricting the analysis to similar scales. We also consider single-parameter extensions to the flat Ī›CDM model. The SPTPOL lensing spectrum constrains the spatial curvature to be Ī©_K = āˆ’0.0007Ā±0.0025 and the sum of the neutrino masses to be āˆ‘m_Ī½ < 0.23 eV at 95% C.L. (with Planck primary CMB and BAO data), in good agreement with the Planck lensing results. With the differences in the signal-to-noise ratio of the lensing modes and the angular scales covered in the lensing spectra, this analysis represents an important independent check on the full-sky Planck lensing measurement

    On the order of vanishing of newforms at cusps

    Get PDF
    Let EE be an elliptic curve over Q\mathbb{Q} of conductor NN. We obtain an explicit formula, as a product of local terms, for the ramification index at each cusp of a modular parametrization of EE by X0(N)X_0(N). Our formula shows that the ramification index always divides 24, a fact that had been previously conjectured by Brunault as a result of numerical computations. In fact, we prove a more general result which gives the order of vanishing at each cusp of a holomorphic newform of arbitary level, weight and character, provided its field of rationality satisfies a certain condition. The above result relies on a purely pp-adic computation of possibly independent interest. Let FF be a non-archimedean local field and Ļ€\pi an irreducible, admissible, generic representation of GL2(F)\mathrm{GL}_2(F). We introduce a new integral invariant, which we call the \emph{vanishing index} and denote eĻ€(l)e_\pi(l), that measures the degree of "extra vanishing" at matrices of level ll of the Whittaker function associated to the newvector of Ļ€\pi. Our main local result writes down the value of eĻ€(l)e_\pi(l) in every case
    • ā€¦
    corecore