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Measurements of a variety of physical properties of muscle tissue have been proposed as objective tests for meat tenderness. We have attempted to single out a specific physical factor, namely tensile stress, and to determine its effect on the ultrastructure of raw and cooked muscle tissue. Extension of this approach to the other physical factors involved in mastication will hopefully establish the structural factors important to meat tenderness.
The bovine semitendenosus muscle (eye round) was obtained either commercially or excised from a carcass aged under controlled conditions for 10 days. Small strips (¼” x ¼” x 1-½”), raw and cooked at 90°C, were subjected to tensile stress and then fixed in glutaraldehyde. A motorized minitensile stage (Fig. 1), designed to be small enough to operate within the SEM, stressed the muscle samples while viewed by a stereomicroscope and simultaneously monitored with a closed circuit TV system. Identical areas of samples subjected to tensile stress could be observed in both the light and scanning electron microscopes (Fig. 2).
SEM of normal arterial endothelium has shown a constant picture of fine longitudinal ridges or folds. These folds are about 15 microns across, and their smooth undulations comprise a “normal” pattern which permits assessment of various types of early endothelial damage.
SEM affords rapid, stereoscopic study of relatively large areas of endothelium with ultrafine detail. Some microvascular maneuvers may mechanically distort or obliterate normal endothelial ridging. In addition, fibrin-platelet-red blood cell deposits may cover damaged endothelium.
Eighty canine middle cerebral arteries, 1.0 - 1.5 mm in diameter, were studied with SEM following: a) microtourniquet and microclip occlusion, b) pinching with jeweler's forceps, c) arteriotomy and suture, d) bipolar coagulation of a side branch 1 mm from the parent artery, 20 mv for 20 seconds, and e) end-to-side microanastomosis.
The initial event in arterial thrombosis is platelet adherence, and then platelet aggregation. These platelet clumps will begin to disperse or “wash out” 20 minutes post aggregation, so that 60 minutes later, platelet dispersion is fairly complete, if total arterial thrombosis and fibrin deposition have not occurred.
Recent evidence suggests that quitline text messaging is an effective treatment for smoking cessation, but little is known about the relative effectiveness of the message content.
A pilot study of the effects of gain-framed (GF; focused on the benefits of quitting) versus loss-framed (LF; focused on the costs of continued smoking) text messages among smokers contacting a quitline.
Participants were randomized to receive LF (N = 300) or GF (N = 300) text messages for 30 weeks. Self-reported 7-day point prevalence abstinence and number of 24 h quit attempts were assessed at week 30. Intent-to-treat (ITT) and responder analyses for smoking cessation were conducted using logistic regression.
The ITT analysis showed 17% of the GF group quit smoking compared to 15% in the LF group (P = 0.508). The responder analysis showed 44% of the GF group quit smoking compared to 35% in the LF group (P = 0.154). More participants in the GF group reported making a 24 h quit attempt compared to the LF group (98% vs. 93%, P = 0.046).
Although there were no differences in abstinence rates between groups at the week 30 follow-up, participants in the GF group made more quit attempts than those in the LF group.
There is considerable interest in the therapeutic potential of Cannabidiol (CBD), the second most abundant component of Cannabis. While delta-9-THC, the main psychoactive ingredient of cannabis, impairs memory and induces anxiety and psychotic symptoms acutely and increases the risk of psychotic disorders in regular cannabis users, CBD does not impair memory, may have anxiolytic and possibly antipsychotic effects. Hence, we compared directly the acute neural effects of these two active ingredients of cannabis, by combining pharmacological challenge with fMRI. Using a double-blind, repeated measures design and oral challenge with 10mg of delta-9-THC, 600mg of CBD or placebo in 15 healthy volunteers, we examined whether delta-9-THC and CBD have opposing effects on the neural substrates of verbal memory and fear processing and whether they also have opposing effects on the neural substrates of anxiety and psychotic symptoms induced by delta-9-THC. Delta-9-THC induced anxiety and psychotic symptoms acutely while there was a trend for a reduction in anxiety but no change in psychotic symptoms with CBD. During the memory task, delta-9-THC attenuated and CBD increased activation in the striatum bilaterally. Effect of delta-9-THC on striatal activation was inversely correlated with the psychotic symptoms induced by it concomitantly. During the processing of fearful faces, delta-9-THC increased and CBD attenuated activation in the amygdala and these effects correlated with their anxiogenic and anxiolytic effects respectively. These opposing effects of CBD on the key neural substrates for psychotic symptoms and anxiety induced by delta-9-THC may suggest its possible therapeutic role in countering these conditions.
Environmental information from place-names has largely been overlooked by geoarchaeologists and fluvial geomorphologists in analyses of the depositional histories of rivers and floodplains. Here, new flood chronologies for the rivers Teme, Severn, and Wye are presented, modelled from stable river sections excavated at Broadwas, Buildwas, and Rotherwas. These are connected by the Old English term *wæsse, interpreted as ‘land by a meandering river which floods and drains quickly’. The results reveal that, in all three places, flooding during the early medieval period occurred more frequently between AD 350–700 than between AD 700–1100, but that over time each river's flooding regime became more complex including high magnitude single events. In the sampled locations, the fluvial dynamics of localized flood events had much in common, and almost certainly differed in nature from other sections of their rivers, refining our understanding of the precise nature of flooding which their names sought to communicate. This study shows how the toponymic record can be helpful in the long-term reconstruction of historic river activity and for our understanding of past human perceptions of riverine environments.
This paper provides an up-to-date review of the problems related to the generation, detection and mitigation of strong electromagnetic pulses created in the interaction of high-power, high-energy laser pulses with different types of solid targets. It includes new experimental data obtained independently at several international laboratories. The mechanisms of electromagnetic field generation are analyzed and considered as a function of the intensity and the spectral range of emissions they produce. The major emphasis is put on the GHz frequency domain, which is the most damaging for electronics and may have important applications. The physics of electromagnetic emissions in other spectral domains, in particular THz and MHz, is also discussed. The theoretical models and numerical simulations are compared with the results of experimental measurements, with special attention to the methodology of measurements and complementary diagnostics. Understanding the underlying physical processes is the basis for developing techniques to mitigate the electromagnetic threat and to harness electromagnetic emissions, which may have promising applications.
A developing application of laser-driven currents is the generation of magnetic fields of picosecond–nanosecond duration with magnitudes exceeding
. Single-loop and helical coil targets can direct laser-driven discharge currents along wires to generate spatially uniform, quasi-static magnetic fields on the millimetre scale. Here, we present proton deflectometry across two axes of a single-loop coil ranging from 1 to 2 mm in diameter. Comparison with proton tracking simulations shows that measured magnetic fields are the result of kiloampere currents in the coil and electric charges distributed around the coil target. Using this dual-axis platform for proton deflectometry, robust measurements can be made of the evolution of magnetic fields in a capacitor coil target.
The Wisconsin Twin Project comprises multiple longitudinal studies that span infancy to early adulthood. We summarize recent papers that show how twin designs with deep phenotyping, including biological measures, can inform questions about phenotypic structure, etiology, comorbidity, heterogeneity, and gene–environment interplay of temperamental constructs and mental and physical health conditions of children and adolescents. The general framework for investigations begins with rich characterization of early temperament and follows with study of experiences and exposures across childhood and adolescence. Many studies incorporate neuroimaging and hormone assays.
Filamentary structures can form within the beam of protons accelerated during the interaction of an intense laser pulse with an ultrathin foil target. Such behaviour is shown to be dependent upon the formation time of quasi-static magnetic field structures throughout the target volume and the extent of the rear surface proton expansion over the same period. This is observed via both numerical and experimental investigations. By controlling the intensity profile of the laser drive, via the use of two temporally separated pulses, both the initial rear surface proton expansion and magnetic field formation time can be varied, resulting in modification to the degree of filamentary structure present within the laser-driven proton beam.
The ideal sampling method and benefit of qualitative versus quantitative culture for carbapenem-resistant Enterobacteriaceae (CRE) recovery in hospitalized patient rooms and bathrooms is unknown. Although the use of nylon-flocked swabs improved overall gram-negative organism recovery compared with cellulose sponges, they were similar for CRE recovery. Quantitative culture was inferior and unrevealing beyond the qualitative results.
Lactobacillus acidophilus fermentation products have been used to improve the performance of nursery pigs. However, research on the influence of this supplement on health is lacking. This study was designed to determine if feeding a Lactobacillus acidophilus fermentation product to weaned pigs would reduce stress and acute phase responses (APR) following a lipopolysaccharide (LPS) challenge. Pigs (n=30; 6.4±0.1 kg) were individually housed in stainless steel pens with ad libitum access to feed and water. Pigs were weighed upon arrival, assigned to one of three groups (n=10/treatment), and fed for 18 days: (1) Control, fed a non-medicated starter diet; (2) Control diet with the inclusion of a Lactobacillus acidophilus fermentation product at 1 kg/metric ton (SGX1) and (3) Control diet with the inclusion of a Lactobacillus acidophilus fermentation product at 2 kg/metric ton (SGX2). On day 7 pigs were anesthetized for insertion of an i.p. temperature device, and similarly on day 14 for insertion of a jugular catheter. Pigs were challenged i.v. with LPS (25 µg/kg BW) on day 15. Blood samples were collected at 0.5 h (serum) and 1 h (complete blood cell counts) intervals from −2 to 8 h and at 24 h relative to LPS administration at 0 h. Pigs and feeders were weighed on days 7, 14 and 18. The supplemented pigs had increased BW and average daily gain before the challenge. In response to LPS, there was a greater increase in i.p. temperature in Control pigs compared with supplemented pigs. In addition, cortisol was reduced in SGX2 pigs while cortisol was elevated in SGX1 pigs at several time points post-challenge. White blood cells, neutrophils and lymphocytes were decreased in SGX1 and SGX2 compared with Control pigs. Furthermore, the pro-inflammatory cytokine response varied by treatment and dose of treatment. Specifically, serum TNF-α was greatest in SGX2, intermediate in Control, and least in SGX1 pigs, while the magnitude and temporal pattern of IFN-γ in SGX2 pigs was delayed and reduced. In contrast, IL-6 concentrations were reduced in both SGX treatment groups compared with Control pigs. These data demonstrate that different supplementation feed inclusion rates produced differential responses, and that feeding SynGenX to weaned pigs attenuated the APR to an LPS challenge.
The fourth edition of Gender and Elections offers a systematic, lively, multi-faceted account of the role of gender in the electoral process through the 2016 elections. This timely, yet enduring, volume strikes a balance between highlighting the most important development for women as voters and candidates in the 2016 elections and providing a more long-term, in-depth analysis of the ways in which gender has helped shape the contours and outcomes of electoral politics in the United States. Individual chapters demonstrate the importance of gender in understanding and interpreting presidential elections, presidential and vice-presidential candidacies, voter participation and turnout, voting choices, congressional elections, the political involvement of Latinas, the participation of African American women, the support of political parties and women's organizations, candidate communications with voters, and state elections. Without question, Gender and Elections is the most comprehensive, reliable, and trustworthy resource on the role of gender in electoral politics.