9,388 research outputs found
Apparatus for cutting elastomeric materials
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
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Does the threat of disqualification deter drivers from speeding?
Road Safety Research Report, number 96, is available from the National Archives: Department for Transport, and can be accessed from the link below.It has long been recognised that driving speeds that are excessive and inappropriate
to the conditions are a major contributory factor in road accidents, and a major issue
for road safety. Restraining driving speeds has proved to be a difficult task, given the
improvements over the years in both vehicle performance and road design.
Within the traditional āthree Esā countermeasures of engineering, education and
enforcement, recent years have seen the introduction of a wide range of engineering
measures designed to bring about speed reduction, but these tend to be restricted to
specific parts of the road network. New technologies such as Intelligent Speed
Adaptation (ISA) offer considerable promise, but mainly in the medium or longer term. Similarly, educative efforts to induce attitude and behaviour change in this context are bearing fruit, yet this is a long-term rather than short-term project. For the foreseeable future, enforcement will remain the principal means of influencing speed, by setting speed limits and imposing sanctions on drivers who are caught exceeding them.
The number of licence endorsements has increased enormously in recent years.
However, over the same period the number of disqualifications resulting from ātotting-upā points has decreased. This would seem to indicate that many drivers who accumulate up to 11 penalty points are either acting as if deterred by the threat of disqualification, or are avoiding disqualification in some other way. The extent to which penalty points act as a deterrent for the benefit of road safety in general is therefore an important issue, and this report describes work that has been carried out to study this issue by TRL and Brunel University, under contract to the Department for Transport
Barefoot running improves economy at high intensities and peak treadmill velocity
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 4Ć4 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.
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
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 SunyaevāZel'dovich Effect in the SPTpol 100-square-degree Survey
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 SunyaevāZel'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) > 2.6Ć10Ā¹ā“Māhā»Ā¹āā 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) > 2.7Ć10Ā¹ā“Māhā»Ā¹āā. 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
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 ĪCDM 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 ĻāĪ©^(0.25)_m = 0.593 Ā± 0.025. Jointly fitting with BAO data, we find Ļā = 0.779Ā±0.023, Ī©_m = 0.368^(+0.032)_(ā0.037), and Hā = 72.0^(+2.1)_(ā2.5)kmsā»Ā¹ Mpcā»Ā¹, up to 2Ļ 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 ĪCDM model. The SPTPOL lensing spectrum constrains the spatial curvature to be Ī©_K = ā0.0007Ā±0.0025 and the sum of the neutrino masses to be ām_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
Let be an elliptic curve over of conductor . We obtain an explicit formula, as a product of local terms, for the ramification index at each cusp of a modular parametrization of by . 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 -adic computation of possibly independent interest. Let be a non-archimedean local field and an irreducible, admissible, generic representation of . We introduce a new integral invariant, which we call the \emph{vanishing index} and denote , that measures the degree of "extra vanishing" at matrices of level of the Whittaker function associated to the newvector of . Our main local result writes down the value of in every case
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