223 research outputs found
The Effect of Music Tempo on Squat Performance
Burket, J., Eubank, T., Reed, C., Sanders, J. Shippensburg University, Shippensburg, PA
Purpose: The purpose of this study was to determine whether music tempo affects squat performance. Methods: A total of eleven healthy college aged subjects (Age range: 18 ~ 22 yrs, Weight: 81.4±12.0 kg, Height: 1.7±0.1 m) volunteered in the study and eight subjects (one female and seven males) completed the study. After obtaining baseline measures, subjects performed heavy barbell squat exercise under three conditions. The three conditions were to perform the squat exercise with load equal to 60% of their body weight until failure while listening to fast tempo (200 bpm), slow tempo (60 bpm) and no music. The order of the trial was randomized and each trial was separated by a minimum of 7 days. Using descriptive statistics and one-way analysis of variance, data were analyzed to compare the difference in performance under three conditions. Results: Compared to fast music and no music condition, subjects performed more repetition of squat under slow music condition (34.8±29.6 vs. 33.5±22.7 vs. 35.1± 37.0 reps). However, the difference was not significant (p\u3e0.05). Although not significant, subjects reported higher rate of perceived exertion (RPE) under slow music condition while exercise heart rate and systolic blood pressure were reported to be lower with slow music condition. Conclusion: The results of the study indicate that music tempo has no significant influence on heavy squat exercise performance or cardiovascular measures during exercise. Future studies are needed to further examine possible effect of music tempo when using a larger variation
TRANSFORMATION INDUCED BY SIMIAN VIRUS 40 IN NEWBORN SYRIAN HAMSTER RENAL CELL CULTURES
On the cyclically fully commutative elements of Coxeter groups
Let W be an arbitrary Coxeter group. If two elements have expressions that are cyclic shifts of each other (as words), then they are conjugate (as group elements) in W. We say that w is cyclically fully commutative (CFC) if every cyclic shift of any reduced expression for w is fully commutative (i.e., avoids long braid relations). These generalize Coxeter elements in that their reduced expressions can be described combinatorially by acyclic directed graphs, and cyclically shifting corresponds to source-to-sink conversions. In this paper, we explore the combinatorics of the CFC elements and enumerate them in all Coxeter groups. Additionally, we characterize precisely which CFC elements have the property that powers of them remain fully commutative, via the presence of a simple combinatorial feature called a band. This allows us to give necessary and sufficient conditions for a CFC element w to be logarithmic, that is, ℓ(wk)=k⋅ℓ(w) for all k≥1, for a large class of Coxeter groups that includes all affine Weyl groups and simply laced Coxeter groups. Finally, we give a simple non-CFC element that fails to be logarithmic under these conditions
SafeWeb: A Middleware for Securing Ruby-Based Web Applications
Web applications in many domains such as healthcare and finance must process sensitive data, while complying with legal policies regarding the release of different classes of data to different parties. Currently, software bugs may lead to irreversible disclosure of confidential data in multi-tier web applications. An open challenge is how developers can guarantee these web applications only ever release sensitive data to authorised users without costly, recurring security audits.
Our solution is to provide a trusted middleware that acts as a “safety net” to event-based enterprise web applications by preventing harmful data disclosure before it happens. We describe the design and implementation of SafeWeb, a Ruby-based middleware that associates data with security labels and transparently tracks their propagation at different granularities across a multi-tier web architecture with storage and complex event processing. For efficiency, maintainability and ease-of-use, SafeWeb exploits the dynamic features of the Ruby programming language to achieve label propagation and data flow enforcement. We evaluate SafeWeb by reporting our experience of implementing a web-based cancer treatment application and deploying it as part of the UK National Health Service (NHS)
Late-Time Spectroscopy of SN 2002cx: The Prototype of a New Subclass of Type Ia Supernovae
We present Keck optical spectra of SN 2002cx, the most peculiar known Type Ia
supernova (SN Ia), taken 227 and 277 days past maximum light. Astonishingly,
the spectra are not dominated by the forbidden emission lines of iron that are
a hallmark of thermonuclear supernovae in the nebular phase. Instead, we
identify numerous P-Cygni profiles of Fe II at very low expansion velocities of
about 700 km/s, which are without precedent in SNe Ia. We also report the
tentative identification of low-velocity O I in these spectra, suggesting the
presence of unburned material near the center of the exploding white dwarf. SN
2002cx is the prototype of a new subclass of SNe Ia, with spectral
characteristics that may be consistent with recent pure deflagration models of
Chandrasekhar-mass thermonuclear supernovae. These are distinct from the
majority of SNe Ia, for which an alternative explosion mechanism, such as a
delayed detonation, may be required.Comment: 18 pages, 5 figures, to appear in The Astronomical Journal; minor
revisions to match accepted versio
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INEXPENSIVE, OFF THE SHELF HYBRID MICROWAVE SYSTEM
A hybrid-heating microwave oven provides the energy to heat small 10-gram samples of spent metal tritide storage bed material to release tenaciously held decay product {sup 3}He. Complete mass balance procedures require direct measurement of added or produced gases on a tritide bed, and over 1100 C is necessary to release deep trapped {sup 3}He. The decomposition of non-radioactive CaCO{sub 3} and the quantitative measurement of CO{sub 2} within 3% of stoichiometry demonstrate the capabilities of the apparatus to capture generated (released) gases
On the Progenitor and Supernova of the SN 2002cx-like Supernova 2008ge
We present observations of supernova (SN) 2008ge, which is spectroscopically
similar to the peculiar SN 2002cx, and its pre-explosion site that indicate
that its progenitor was probably a white dwarf. NGC 1527, the host galaxy of SN
2008ge, is an S0 galaxy with no evidence of star formation or massive stars.
Astrometrically matching late-time imaging of SN 2008ge to pre-explosion HST
imaging, we constrain the luminosity of the progenitor star. Since SN 2008ge
has no indication of hydrogen or helium in its spectrum, its progenitor must
have lost its outer layers before exploding, requiring that it be a white
dwarf, a Wolf-Rayet star, or a lower-mass star in a binary system. Observations
of the host galaxy show no signs of individual massive stars, star clusters, or
H II regions at the SN position or anywhere else, making a Wolf-Rayet
progenitor unlikely. Late-time spectroscopy of SN 2008ge show strong [Fe II]
lines with large velocity widths compared to other members of this class at
similar epochs. These previously unseen features indicate that a significant
amount of the SN ejecta is Fe (presumably the result of radioactive decay of
56Ni generated in the SN), further supporting a thermonuclear explosion.
Placing the observations of SN 2008ge in the context of observations of other
objects in the class of SN, we suggest that the progenitor was most likely a
white dwarf.Comment: 9 pages, 6 figures, accepted by A
Comparisons of the radial distributions of core-collapse supernovae with those of young and old stellar populations
We present observational constraints on the nature of core-collapse
supernovae through an investigation into their radial distributions with
respect to those of young and old stellar populations within their host
galaxies, as traced by H-alpha emission and R-band light respectively. We
discuss results and the implications they have on the nature of supernova
progenitors, for a sample of 177 core-collapse supernovae. We find that the
radial positions of the overall core-collapse population closely follow the
radial distribution of H-alpha emission, implying that both are excellent
tracers of star formation within galaxies. Within this overall distribution we
find that there is a central deficit of SNII which is offset by a central
excess of SNIb/c. This implies a strong metallicity dependence on the relative
production of the two types, with SNIb/c arising from higher metallicity
progenitors than SNII. Separating the SNIb/c into individual classes we find
that a trend emerges in terms of progenitor metallicity going from SNII through
SNIb to SNIc, with the latter arising from the highest metallicity progenitors.Comment: Accepted for publication in MNRA
Radioactive Demonstration Of Mineralized Waste Forms Made From Hanford Low Activity Waste (Tank SX-105, Tank AN-103, And AZ-101/102) By Fluidized Bed Steam Reformation (FBSR)
Fluidized Bed Steam Reforming (FBSR) is a robust technology for the immobilization of a wide variety of radioactive wastes. Applications have been tested at the pilot scale for the high sodium, sulfate, halide, organic and nitrate wastes at the Hanford site, the Idaho National Laboratory (INL), and the Savannah River Site (SRS). Due to the moderate processing temperatures, halides, sulfates, and technetium are retained in mineral phases of the feldspathoid family (nepheline, sodalite, nosean, carnegieite, etc). The feldspathoid minerals bind the contaminants such as Tc-99 in cage (sodalite, nosean) or ring (nepheline) structures to surrounding aluminosilicate tetrahedra in the feldspathoid structures. The granular FBSR mineral waste form that is produced has a comparable durability to LAW glass based on the short term PCT testing in this study, the INL studies, SPFT and PUF testing from previous studies as given in the columns in Table 1-3 that represent the various durability tests. Monolithing of the granular product was shown to be feasible in a separate study. Macro-encapsulating the granular product provides a decrease in leaching compared to the FBSR granular product when the geopolymer is correctly formulated
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