The effects of concurrent strength and muscular endurance resistance training on strength, endurance and body composition in previously untrained females

The number of females engaged in some form of sporting activity is growing rapidly, but many women still shy away from weight training because of their fear of excessive muscular hypertrophy and its accompanying loss of femininity. Because strength and muscular endurance play a vital role in most sporting endeavours, and weight training has proven to be one of the most effective methods to improve both attributes, any training regime that could achieve concurrent increases in both measures without noticeable increases in muscle size would be ideally suited to most women. Changes in strength and endurance resulting from eight weeks resistance training of the non-dominant elbow flexors were followed in 11 females using either a high repetition low resistance training regime [Endurance], a low repetition moderate resistance training regime[Strength], or a combination routine alternating between the two regimes [Combined]. Changes in body weight, limb girth or skinfolds were also monitored. The occurrence and severity of any delayed onset muscle soreness (DOMS) based on the subjective assessment by each participant was also monitored. Strength gains [as measured by 1 RM preacher bench curls] were apparent in response to all training regimes [E: S: C], with mean pre-post increases of 11.9%, 12.0% and 10.5% respectively. Isometric peak torque tests produced only one statistically significant mean pre-post strength increase [20.5%], and that was achieved by the S group. Isokinetic peak torque measurements at 30° per second produced significant mean pre-post increases for both the S and C groups of 17.7% and 17.0% respectively, but when the assessment speed was increased to 90° per second only the 22.9% increase posted by the C group was found to fall within the selected (p\u3c . 05) level of statistical significance. Changes in muscular endurance were assessed using the total work produced during 25 continuous repetitions at 90° per second, and the only statistically significant increase was achieved by the C group. The results of this study showed that gains in strength and muscular endurance can be made by previously untrained females in response to 8 weeks of alternating concurrent moderate f/0-75% 1RM) intensity /low (5 x 6 repetition) volume, and low ( 40-45% l RM) intensity I moderate (5 x 25 repetition) volume training regimes, and that strength gains could be achieved without noticeable DOMS or any significant increases in muscle girth measurements

Investigation and characterization of constraint effects on flaw growth during fatigue loading of composite materials

An investigative program is presented in an attempt to add to the current understanding of constraint effects on the response of composite materials under cyclic loading. The objectives were: (1) to use existing data and to develop additional data in order to establish an understanding and quantitative description of flaw growth in unidirectional lamina under cyclic loading at different load direction to fiber direction angles; (2) to establish a similar understanding and description of flaw growth in lamina which are embedded in laminates between other unflawed lamina; (3) to determine the nature of the influence of constraint on flaw growth by quantitatively comparing the results of the tests; and (4) to develop a model and philosophy of constraints effects based on our investigative results

The Selection, Use, and Maintenance of the Modalities of Physical Therapy by Selected Professional Athletic Trainers in the Dallas-Fort Worth Area

The study involved a survey of the selection, use, and maintenance of modalities of physical therapy by selected professional athletic trainers of high school, college, and professional athletic teams in the Dallas-Fort Worth area

The role of plasma membrane STIM1 and Ca2+entry in platelet aggregation. STIM1 binds to novel proteins in human platelets

Ca(2+) elevation is essential to platelet activation. STIM1 senses Ca(2+) in the endoplasmic reticulum and activates Orai channels allowing store-operated Ca(2+) entry (SOCE). STIM1 has also been reported to be present in the plasma membrane (PM) with its N-terminal region exposed to the outside medium but its role is not fully understood. We have examined the effects of the antibody GOK/STIM1, which recognises the N-terminal region of STIM1, on SOCE, agonist-stimulated Ca(2+) entry, surface exposure, in vitro thrombus formation and aggregation in human platelets. We also determined novel binding partners of STIM1 using proteomics. The dialysed GOK/STIM1 antibody failed to reduced thapsigargin- and agonist-mediated Ca(2+) entry in Fura2-labelled cells. Using flow cytometry we detect a portion of STIM1 to be surface-exposed. The dialysed GOK/STIM1 antibody reduced thrombus formation by whole blood on collagen-coated capillaries under flow and platelet aggregation induced by collagen. In immunoprecipitation experiments followed by proteomic analysis, STIM1 was found to extract a number of proteins including myosin, DOCK10, thrombospondin-1 and actin. These studies suggest that PM STIM1 may facilitate platelet activation by collagen through novel interactions at the plasma membrane while the essential Ca(2+)-sensing role of STIM1 is served by the protein in the ER

An absolutely calibrated survey of polarized emission from the northern sky at 1.4 GHz

A new polarization survey of the northern sky at 1.41 GHz is presented. The observations were carried out using the 25.6m telescope at the Dominion Radio Astrophysical Observatory in Canada, with an angular resolution of 36 arcmin. The data are corrected for ground radiation to obtain Stokes U and Q maps on a well-established intensity scale tied to absolute determinations of zero levels, containing emission structures of large angular extent, with an rms noise of 12 mK. Survey observations were carried out by drift scanning the sky between -29 degr and +90 degr declination. The fully sampled drift scans, observed in steps of 0.25 degr to 2.5 degr in declination, result in a northern sky coverage of 41.7% of full Nyquist sampling. The survey surpasses by a factor of 200 the coverage, and by a factor of 5 the sensitivity, of the Leiden/Dwingeloo polarization survey (Spoelstra 1972) that was until now the most complete large-scale survey. The temperature scale is tied to the Effelsberg scale. Absolute zero-temperature levels are taken from the Leiden/Dwingeloo survey after rescaling those data by the factor of 0.94. The paper describes the observations, data processing, and calibration steps. The data are publicly available at http://www.mpifr-bonn.mpg.de/div/konti/26msurvey or http://www.drao.nrc.ca/26msurvey.Comment: 18 pages, 11 figures, accepted for publication in Astronomy and Astrophysic

The chaperone protein HSP47: a platelet collagen binding protein that contributes to thrombosis and haemostasis

Objective: Heat shock protein 47 (HSP47) is an intracellular chaperone protein that is vital for collagen biosynthesis in collagen secreting cells. This protein has also been shown to be present on the surface of platelets. Given the importance of collagen and its interactions with platelets in triggering haemostasis and thrombosis, in this study we sought to characterise the role of HSP47 on these cells. Approach and Results: The deletion of HSP47 in mouse platelets or its inhibition in human platelets reduced their function in response to collagen and the GPVI agonist (CRP-XL), but responses to thrombin were unaltered. In the absence of functional HSP47, the interaction of collagen with platelets was reduced, and this was associated with reduced GPVI-collagen binding, signalling and platelet activation. Thrombus formation on collagen, under arterial flow conditions was also decreased following the inhibition or deletion of HSP47, in the presence or absence of the eptifibatide, consistent with a role for HSP47 in enhancing platelet adhesion to collagen. Platelet adhesion under flow to von Willebrand Factor was unaltered following HSP47 inhibition. Laser-induced thrombosis in cremaster muscle arterioles was reduced and bleeding time was prolonged in HSP47 deficient mice or following inhibition of HSP47. Conclusions: Our study demonstrates the presence of HSP47 on the platelet surface where it interacts with collagen, stabilises platelet adhesion and increases collagen mediated signalling and therefore thrombus formation and haemostasis

The tyrosine phosphatase CD148 is an essential positive regulator of platelet activation and thrombosis

Platelets play a fundamental role in hemostasis and thrombosis. They are also involved in pathologic conditions resulting from blocked blood vessels, including myocardial infarction and ischemic stroke. Platelet adhesion, activation, and aggregation at sites of vascular injury are regulated by a diverse repertoire of tyrosine kinase–linked and G protein–coupled receptors. Src family kinases (SFKs) play a central role in initiating and propagating signaling from several platelet surface receptors; however, the underlying mechanism of how SFK activity is regulated in platelets remains unclear. CD148 is the only receptor-like protein tyrosine phosphatase identified in platelets to date. In the present study, we show that mutant mice lacking CD148 exhibited a bleeding tendency and defective arterial thrombosis. Basal SFK activity was found to be markedly reduced in CD148-deficient platelets, resulting in a global hyporesponsiveness to agonists that signal through SFKs, including collagen and fibrinogen. G protein–coupled receptor responses to thrombin and other agonists were also marginally reduced. These results highlight CD148 as a global regulator of platelet activation and a novel antithrombotic drug targe

A novel method for the nitration of deactivated aromatic compounds

Novel nitration systems comprising nitric acid, trifluoroacetic anhydride and zeolite Hβ, with or without acetic anhydride, are described. The system having no acetic anhydride is more active and readily nitrates deactivated substrates such as nitrobenzene, benzonitrile, benzoic acid or 4-nitrotoluene to give predominantly the product substituted meta to the deactivating group. The system incorporating acetic anhydride is more moderate in activity, and nitrates moderately deactivated systems such as halogenobenzenes quantitatively within two hours at ice–salt bath temperature, and provides very high selectivity for the para-nitrated product. This system also nitrates 2-nitrotoluene to give high selectivity for 2,4-dinitrotoluene production. Furthermore, the system can be used for direct double nitration of toluene and gives a 92% yield of 2,4-dinitrotoluene with a 2,4-∶2,6-dinitrotoluene ratio of 25∶1. Even greater selectivity (96% yield and 70∶1 selectivity) can be achieved in the latter reaction by conducting the reaction in one flask but in two stages, with trifluoroacetic anhydride added only in the second stage