A Holographic Study of the Gauged NJL Model

The Nambu Jona-Lasinio model of chiral symmetry breaking predicts a second order chiral phase transition. If the fermions in addition have non-abelian gauge interactions then the transition is expected to become a crossover as the NJL term enhances the IR chiral symmetry breaking of the gauge theory. We study this behaviour in the holographic Dynamic AdS/QCD description of a non-abelian gauge theory with the NJL interaction included using Witten's multi-trace prescription. We study the behaviour of the mesonic spectrum as a function of the NJL coupling and the ratio of the UV cut off scale to the dynamical scale of the gauge theory.Comment: 5 pages, 9 figures, added figur

Along Navajo Trails: Recollections of a Trader, 1898-1948

Will Evans\u27s writings should find a special niche in the small but significant body of literature from and about traders to the Navajos. Evans was the proprietor of the Shiprock Trading Company. Probably more than most of his fellow traders, he had a strong interest in Navajo culture. The effort he made to record and share what he learned certainly was unusual. He published in the Farmington and New Mexico newspapers and other periodicals, compiling many of his pieces into a book manuscript. His subjects were Navajos he knew and traded with, their stories of historic events such as the Long Walk, and descriptions of their culture as he, an outsider without academic training, understood it. Evans\u27s writings were colored by his fondness for, uncommon access to, and friendships with Navajos, and by who he was: a trader, folk artist, and Mormon. He accurately portrayed the operations of a trading post and knew both the material and artistic value of Navajo crafts. His art was mainly inspired by Navajo sandpainting. He appropriated and, no doubt, sometimes misappropriated that sacred art to paint surfaces and objects of all kinds. As a Mormon, he had particular views of who the Navajos were and what they believed and was representative of a large class of often-overlooked traders. Much of the Navajo trade in the Four Corners region and farther west was operated by Mormons. They had a significant historical role as intermediaries, or brokers, between Native and European American peoples in this part of the West. Well connected at the center of that world, Evans was a good spokesperson. Will Evans did not publish his book in his lifetime, but his granddaughter Susan Evans Woods reached that goal with the assistance of historian Robert McPherson, who has authored numerous books on Navajo and Four Corners history. Their edition is illustrated with an equally significant, rare selection of photos from the collections of Evans and his colleagues.https://digitalcommons.usu.edu/usupress_pubs/1047/thumbnail.jp

The effect of intermittent exercise on mechanical loading and biomarkers of bone metabolism

Introduction: Bone is a metabolically active tissue which plays a multifunctional role within the body. Animal models have provided evidence demonstrating that dynamic and unaccustomed mechanical loads imposed by gravity and/or muscle activation which exceed the customary strain stimulus are anabolic for bone. Moreover, because the bone’s response to multiple cycles diminishes over time, the inclusion of rest periods between loading cycles has been shown to augment the osteogenic response by allowing the mechanosensory system to re-initialise. As such, rest-inserted intermittent exercise might offer a favourable environment for bone adaptation beyond traditional continuous exercise. Despite this many still engage in continuous aerobic exercise training such as continuous running, which might be deleterious to bone. The use of interval or intermittent running has been proposed as an alternative to reduce bone fatigue and maximise bone accrual more so than continuous exercise. However, evidence for the benefits of intermittent load-bearing exercise on bone adaptation is confined to animal models. Therefore, the aims of the thesis were (1) to investigate the effect of intermittent exercise of varying exercise-to-rest durations with a fixed ratio on the mechanical loading dose, assessed via components of the ground reaction force (GRF), and the osteogenic index, and (2) and to establish the magnitude of effect of intermittent load-bearing exercise on changes in bone tissue, using bone turnover markers compared to a non-exercising control condition.Study 1 The Force 3 non-motorised treadmill (NMT) was used throughout the thesis because of its ability to measure vertical (vGRF) and anterior horizontal (hGRF) GRF continuously during exercise, and its capacity to reflect intermittent movement patterns which are not as easily replicable on a motorised treadmill (MT). However, a preliminary study to investigate; (1) the cardiorespiratory responses to running on an NMT compared to an MT, and (2) establish appropriate reference speeds to dose intermittent performance for subsequent protocols on the NMT was required. Therefore, the aim of study one was to establish the validity of peak cardiorespiratory responses to intermittent and continuous graded exercise tests (GXTs) on a NMT compared to an MT. When a continuous GXT is performed on the NMT a similar maximal oxygen uptake can be achieved (̇2) compared to that achieved on the MT (P = 1.00, d = 0.01, trivial). However, there was a reduction in peak heart rate (P = 0.0001, d = 0.9, moderate), and peak speed is reduced by ~30%. When an intermittent GXT (15 x 15 s) is performed on a NMT, a similar ̇2 can be achieved (P = 0.701, d = 0.16, trivial), together with smaller reductions in peak HR (P = 0.170, d = 0.34, small), and peak speed (P = 0.009, d = 0.8, moderate) compared to a continuous MT running. Conversely, 30 x 30 s had a statistically significant reduction in ̇2 (P = 0.04, d = 0.37, small) and peak HR (P = 0.0001, d = 0.57, small) compared to the Cont-MT. As such, the shorter 15 x 15 s GXT was used to obtain reference speeds for subsequent studies (Studies 2-4).Study 2 The osteogenic potential of impact exercise can be quantified from the analysis of kinetic (peak vGRF, load rate and vertical impulse) variables with greater peak vGRF, load rate and vertical impulse reflecting (indirectly) the magnitude and rate of the mechanical load applied to bone tissue. Our aim was to establish how manipulating the duration and frequency of exercise-to-rest intervals might change the mechanical loading environment using a fixed 1:1 ratio. Twelve healthy active males performed five 45 min intermittent running protocols on the NMT. Experiment 1: three of the intermittent protocols differed in their exercise-to-rest durations (5 s intervals [5s-Int], 20 s intervals [20s-Int] and 80 s intervals [80s-Int]). Experiment 2: three of the protocols differed in the rate of acceleration and deceleration but matched for the exercise-to-rest duration (20 s by 2 s intervals [20s2s-Int], 20 s by 4 s [20s4s-Int] and 20 s by 6 s [20s6s-Int]). The primary outcome measures for experiment 1 & 2 were mean and peak vGRF, vertical impulse, load rate and the intra-step variability assessed via the coefficient of variance (%CV) of the kinetic and kinematic data. There was no statistical difference between conditions for impulse (P = 0.175), maximum load rate (LR) (P = 0.104) or average load rate (ALR) (P =0.345). Peak vGRF data were statistically different between conditions (P = 0.023) with the 5s-Int being greater than the 80s-Int (P = 0.022). There was a statistical effect of condition on all CV data for vertical impulse (P = 0.0001), load rate (P = 0.0001), vGRF (P = 0.0001), kVert (P =0.0001) and kLeg (P = 0.0001) with the 5s-Int & 20s-Int being higher than the 80s-Int. The similarity in the mean GRF data are likely due to the higher loads generated during higher speeds being counteracted by the lower loads at the lower speeds. The variability in the data are caused by the variation between the high and low speeds.Study 3 The magnitude, rate and frequency of the mechanical load are proportional to the amount of bone adaptation. These components were considered in isolation in study 2. However, the components can be combined into one mathematical algorithm, the osteogenic index (OI), to assess the osteogenic potential of the exercise. However, because we demonstrated no statistical effect on mean loading due to the higher loads being counteracted by the lower loads, it is unlikely that the traditional OI can distinguish between the variable loading environments of more intermittent exercise. A novel approach has been developed which incorporates the magnitude and rate of the loading dose across a frequency spectra. The number of loading segments of a particular exercise can then be categorised into the magnitude, intensity and frequency. As yet this method has only been utilised with accelerometers and only during steady-state conditions. Experiment one: There was a statistically significant difference between conditions for the OI_fft (P = 0.0001). The OI_fft was highest for the 80s-Int being 28% greater than the 5s-Int and 23% greater than the 20s-Int. There was a statistically significant 3-way interaction for condition*frequency band*intensity (P = 0.012) with the more intermittent conditions having a higher loading dose at higher frequencies. Experiment two: There was a significant main effect for condition for the mean differences of the OI_fft between conditions (P = 0.033). There was no significant effect of condition for the OI_BW (P = 0.572). There was no significant 3-way interact for condition*frequency band*loading intensity (P = 0.870). When the magnitude, intensity and frequency of multiple loading segments are considered, intermittent locomotion allows the individual to obtain higher magnitudes of loading dose, shifting towards a higher frequency band. It is unclear whether the intermittent protocol might offer a more favourable loading environment due to the more variable loading patterns with greater magnitudes of load at higher frequencies.Study 4: Whilst brief continuous load-bearing exercise increases bone remodelling in favour of resorption, it is unclear how intermittent exercise effects acute bone remodelling. Our aim was to investigate the effect of varying degrees of intermittent exercise, with a fixed exercise-to-rest ratio, on acute bone remodelling, as measured by bone turnover biomarkers. It was hypothesised that the more intermittent protocol would result in a greater bone turnover compared to the non-exercising control and less intermittent conditions. The same exercise protocols from study 2 and 3 were used. Venous blood samples were collected at the same time of day following a 12 h fast at baseline, 1 h, 2 h and 24 h post-exercise. Carboxyterminal crosslinked telopeptide (CTX-1) and procollagen type 1 amino terminal propeptide (P1NP) were used as markers of bone resorption and formation, respectively. There was a significant main effect for time (P = 0.0001), condition (P = 0.032) and a significant condition by time interaction (P = 0.001) for CTX-I. At 1 h the 20s-Int and 5s-Int were higher than the control condition (20s-Int: P = 0.0001, 5s-Int: P = 0.010). There was no significant condition by time interactions for P1NP. The results confirm that bone remodelling is stimulated acutely by load-bearing exercise. Very short and short interval intermittent exercise results in greater bone turnover compared to longer interval intermittent exercise.Conclusion: The effect of different exercise-to-rest intervals, and therefore different frequency of intermittency did not have an effect on the mean vGRF, load rate, vertical impulse or osteogenic index. However, as expected there was a greater intra-step variability in these measures leading to a more variable mechanical loading environment which might offer a more favourable loading environment for bone. Indeed, when bone tissue turnover was assessed using traditional bone turnover markers all exercise conditions demonstrated an increase in bone resorption compared to a non- exercising control condition at 1 h. However, only the short and very short intervals were statistically elevated above control. Therefore, very short and short intermittent exercise might cause greater bone resorption in the prevailing hours following exercise which could stimulate an increase bone formation

Distribution and abundance of Ophiothrix suensonii on sponge vs. non-sponge habitat at Whale Shoals patch reef, Belize

The morphological and chemical properties of sponges can offer unique habitat opportunities to brittle stars in coral reef environments. This study tests for the existence of an association between a brittle star (Ophiothrix suensonii) and a tube sponge (Callyspongia vaginalis) in a Belizean patch reef. Frequencies of O. suensonii on paired plots with and without C. vaginalis clusters were compared. Brittle star abundance was significantly greater on plots containing C. vaginalis; individuals were densely packed within and between the sponge’s protective tubes. Few brittle stars were also found clinging to soft corals and to other Porifera. Although O. suensonii is not an obligate sponge dweller, these brittle stars are a primary inhabitant of C. vaginalis, which offers unique morphological protection from fish predation. The results of this study highlight the importance of species-specific invertebrate symbioses in Belizean patch reefs where habitat options are limited and predation is intense

Mister Worry

Contains advertisements and/or short musical examples of pieces being sold by publisher.https://digitalcommons.library.umaine.edu/mmb-vp/7010/thumbnail.jp

An Investigation into the Correlation of Small Punch and Uniaxial Creep Data for Waspaloy

Within the aerospace sector, the understanding and prediction of creep strains for materials used in high-temperature applications, such as Nickel-based super alloys, is imperative. Small punch testing offers the potential for understanding creep behavior using much less material than conventional uniaxial testing but in contrast to uniaxial creep tests, the stress in small punch creep (SPC) tests is multiaxial. SPC testing can be a valuable tool for validating models of creep deformation, but the key to unlocking its full capability is through the accurate correlation of the creep material properties measured through both techniques. As such, the focus of this paper is to correlate the creep behavior of Waspaloy obtained through conventional uniaxial testing to that obtained via small punch creep testing. Recently, and for low chrome steels, this has been achieved through use of the ksp method, but there are good reasons for believing this technique will not work so well for Nickel-based super alloys. This paper shows this to be the case for Waspaloy and proposes some alternative methods of correlation based on combining the Monkman–Grant relation and the Wilshire equations for both uniaxial and small punch creep. It was found that this latter approach enabled the accurate conversion of SPC minimum displacement rates to equivalent uniaxial minimum creep rates which, when combined with the Wilshire equations, enabled SPC test loads to be converted into equivalent uniaxial stresses (and visa versa) with levels of accuracy that were significantly reduced when compared to using the ksp method. Further, the random error associated with these conversions were dramatically increased

Investigating the thermal profile of a marine vessel engine room through simulation with field measurements

This paper assesses the use of computational fluid dynamics (CFD) to model the ventilation of a working marine vessel, its performance in extreme climates, and potential improvements to the ventilation system which could lead to increased efficiencies of the engine and generator set.Comparisons between data gathered on the marine vessel and the computational model show good agreement, with an average discrepancy in temperature of 0.4%. The model showed that the current ventilation system was inadequate for the use of the marine vessel in Arctic waters. In contrast, the model showed the vessel was suited for tropical waters, and that the boat complied with British Standards for ventilation.Directing the flow within the engine room was found to improve the overall cooling of the room, and reduce the range of temperatures to improve thermal comfort. Directing the flow has shown reduced intake temperatures of the engine and generator set, improving efficiencies by 0.5% and 0.57% respectively. This paper demonstrates that the use of CFD to model marine vessel engine rooms can be used in retrospective design of ventilation systems, furthermore, it can be a tool utilised in the design stages for optimised engine rooms ventilation systems

A tale of two situations: a case report of the merger between dermatology outcomes and prescription drug access

This case report illustrates a case of guttate psoriasis in a young adult and the logistical role dermatologists can play in patients acquiring their prescriptions and improving the quality of their care