3,008 research outputs found

    Thoracic Injury Effects Of Linear And Angular Karate Impacts

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    Skilled karate practitioners are reputed to be able to completely disable an opponent with one blow -- when necessary. Immediate questions arise as to whether karate participants: (a) can, in fact, deliver disabling injurious blows to the thorax, (b) can have a greater ability to damage the body with some technique types over others, and (c) can wear readily available safety equipment to temper blows to below the level of medically severe injury. The viscous response criteria (VCmax), based on chest compression and compression velocity, has been devised to estimate level of injury to the thorax or chest. Accordingly, a VCmax =1.0 m/s is the level for a 25% probability of severe injury, such as liver or lung laceration. Twelve international class karate competitors of 3rd, 4th, and 5th degree or higher (master class) black belt ranks, were evaluated impacting the thorax of an instrumented anthropometric test dummy (ATD) to determine the probable injury effects of linear (thrusting) and angular (striking or snapping) types of karate blows, with and without a chest protector. Techniques evaluated were the roundhouse kick, backfist strike, side-thrust kick, and the reverse punch. Data were analyzed using a 2*3*4 ANOVA design with Tukey's Studentized Range follow-up tests to discriminate within condition differences. The adjusted viscous response (VCmax) was the variable used for evaluation. Of the three skill classes evaluated, 3rd (M =1.2096, SD =.5309) and 4th (M =1.1127, SD =.4304) degree ranks generated statistically higher VCmax levels than master class competitors (M =.8036, SD =.2797) across all conaitions, F (2, 60) =7.57, F = .0012. The chest protector was found to be effective, F 0,60) =4.28, F =.0430, in attenuating the impact effects below the serious injury level (M =1.1382, SD = .4423 and M =.9535, SD = .4575, without and with the chest protector, respectively). The roundhouse kick (M =1.3778, SD =.4674) generated higher .VCmax than all other techniques, F (3, 60) =7.17, F = .0003,: the reverse punch (M =1.0122, SD =.3923); the side-thrust kick (M =.9538, SD =.4976); or the backfist strike (M =.8189, SD =.2986). No statistical difference was detected among the technique conditions. It was concluded that the highly skilled karate competitor could deliver severe or greater levels of damage to the thorax with karate techniques, especially the roundhouse kick. The level of damage to the thorax can be reduced below the "serious" level with the use of a chest protector

    Non-malleable codes for space-bounded tampering

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    Non-malleable codes—introduced by Dziembowski, Pietrzak and Wichs at ICS 2010—are key-less coding schemes in which mauling attempts to an encoding of a given message, w.r.t. some class of tampering adversaries, result in a decoded value that is either identical or unrelated to the original message. Such codes are very useful for protecting arbitrary cryptographic primitives against tampering attacks against the memory. Clearly, non-malleability is hopeless if the class of tampering adversaries includes the decoding and encoding algorithm. To circumvent this obstacle, the majority of past research focused on designing non-malleable codes for various tampering classes, albeit assuming that the adversary is unable to decode. Nonetheless, in many concrete settings, this assumption is not realistic

    A water-vapor electrolysis cell with phosphoric acid electrolyte

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    Feasibility of phosphoric acid water vapor electrolysis cell for spacecraft cabin air conditioning syste

    Development of large-internal-surface-area nickel-metal plaques Final report, Jun. 18, 1964 - Sep. 30, 1965

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    Large internal surface area porous nickel metal plaques for rechargeable cadmium electrodes to improve nickel-cadmium batterie

    Cephalosporin-3’-diazeniumdiolate NO-donor prodrug PYRRO-C3D enhances azithromycin susceptibility of non-typeable Haemophilus influenzae biofilms

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    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Objectives: PYRRO-C3D is a cephalosporin-3-diazeniumdiolate nitric oxide (NO)-donor prodrug designed to selectively deliver NO to bacterial infection sites. The objective of this study was to assess the activity of PYRRO-C3D against non-typeable Haemophilus influenzae (NTHi) biofilms and examine the role of NO in reducing biofilm-associated antibiotic tolerance. Methods: The activity of PYRRO-C3D on in vitro NTHi biofilms was assessed through CFU enumeration and confocal microscopy. NO release measurements were performed using an ISO-NO probe. NTHi biofilms grown on primary ciliated respiratory epithelia at an air-liquid interface were used to investigate the effects of PYRRO-C3D in the presence of host tissue. Label-free LC/MS proteomic analyses were performed to identify differentially expressed proteins following NO treatment. Results: PYRRO-C3D specifically released NO in the presence of NTHi, while no evidence of spontaneous NO release was observed when the compound was exposed to primary epithelial cells. NTHi lacking β-lactamase activity failed to trigger NO release. Treatment significantly increased the susceptibility of in vitro NTHi biofilms to azithromycin, causing a log-fold reduction in viability (p<0.05) relative to azithromycin alone. The response was more pronounced for biofilms grown on primary respiratory epithelia, where a 2-log reduction was observed (p<0.01). Label-free proteomics showed that NO increased expression of sixteen proteins involved in metabolic and transcriptional/translational functions. Conclusions: NO release from PYRRO-C3D enhances the efficacy of azithromycin against NTHi biofilms, putatively via modulation of NTHi metabolic activity. Adjunctive therapy with NO mediated through PYRRO-C3D represents a promising approach for reducing biofilm associated antibiotic tolerance

    Geospatial analysis and living urban geometry

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    This essay outlines how to incorporate morphological rules within the exigencies of our technological age. We propose using the current evolution of GIS (Geographical Information Systems) technologies beyond their original representational domain, towards predictive and dynamic spatial models that help in constructing the new discipline of "urban seeding". We condemn the high-rise tower block as an unsuitable typology for a living city, and propose to re-establish human-scale urban fabric that resembles the traditional city. Pedestrian presence, density, and movement all reveal that open space between modernist buildings is not urban at all, but neither is the open space found in today's sprawling suburbs. True urban space contains and encourages pedestrian interactions, and has to be designed and built according to specific rules. The opposition between traditional self-organized versus modernist planned cities challenges the very core of the urban planning discipline. Planning has to be re-framed from being a tool creating a fixed future to become a visionary adaptive tool of dynamic states in evolution
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