480 research outputs found

    Dinosaur footprints and other Ichnofauna from the Cretaceous Kem Kem Beds of Morocco

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    We describe an extensive ichnofossil assemblage from the likely Cenomanian-age 'lower' and 'upper' units of the 'Kem Kem beds' in southeastern Morocco. In the lower unit, trace fossils include narrow vertical burrows in cross-bedded sandstones and borings in dinosaur bone, with the latter identified as the insect ichnotaxon Cubiculum ornatus. In the upper unit, several horizons preserve abundant footprints from theropod dinosaurs. Sauropod and ornithischian footprints are much rarer, similar to the record for fossil bone and teeth in the Kem Kem assemblage. The upper unit also preserves a variety of invertebrate traces including Conichnus (the resting trace of a sea-anemone), Scolicia (a gastropod trace), Beaconites (a probable annelid burrow), and subvertical burrows likely created by crabs for residence and detrital feeding on a tidal flat. The ichnofossil assemblage from the Upper Cretaceous Kem Kem beds contributes evidence for a transition from predominantly terrestrial to marine deposition. Body fossil and ichnofossil records together provide a detailed view of faunal diversity and local conditions within a fluvial and deltaic depositional setting on the northwestern coast of Africa toward the end of the Cretaceous

    Principal component analysis and biochemical characterization of protein and starch reveal primary targets for improving sorghum grain

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    Limited progress has been made on genetic improvement of the digestibility of sorghum grain because of variability among different varieties. In this study, we applied multiple techniques to assess digestibility of grain from 18 sorghum lines to identify major components responsible for variability. We also identified storage proteins and enzymes as potential targets for genetic modification to improve digestibility. Results from principal component analysis revealed that content of amylose and total starch, together with protein digestibility (PD), accounted for 94% of variation in digestibility. Control of amylose content is understood and manageable. Up-regulation of genes associated with starch accumulation is clearly a future target for improving digestibility. To identify proteins that might be targets for future modification, meal from selected lines was digested in vitro with pancreatin in parallel with pepsin and α-amylase. The %PD was influenced by both the nature of the protein matrix and protein body packaging. Owing to its ability to form oligomers, the 20 kDa γ-kafirin was more resistant to digestion than counterparts lacking this ability, making it a target for down-regulation. Greater understanding of interactions among the three traits identified by principal component analysis is needed for both waxy and non-waxy varieties

    Effects of Calcium β-HMB Supplementation During Training on Markers of Catabolism, Body Composition, Strength and Sprint Performance

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    Calcium β-hydroxy β-methylbutyrate (HMB) supplementation has been reported to reduce catabolism and promote gains in strength and fat free mass in untrained individuals initiating training. However, the effects of HMB supplementation on strength and body composition alterations during training in athletes is less clear. This study examined the effects of 28-d of calcium HMB supplementation during intense training on markers of catabolism, body composition, strength, and sprint performance. In a double-blind and randomized manner, 28 NCAA division I-A football players were matched-paired and assigned to supplement their diet for 28-d during winter resistance/agility training (~8 hr/wk) with a carbohydrate placebo supplement (P) or the P supplement with 3 g/day of HMB as a calcium salt (HMB). Prior to and following supplementation: dietary records and fasting blood samples were obtained; body composition was determined via DEXA; subjects performed maximal effort bench press, barbell back squat, and power clean isotonic repetition tests; and, subjects performed a repeated cycle ergometer sprint test (12 x 6-s sprints with 30-s rest recovery) to simulate a 12-play drive in football. Results revealed no significant differences between the placebo and HMB supplemented groups in markers of catabolism, muscle/liver enzyme efflux, hematological parameters, body composition, combined lifting volume, or repetitive sprint performance. Results indicate that HMB supplementation (3 g/day) during off-season college football resistance/agility training does not reduce catabolism or provide ergogenic benefit

    Factors Governing Pasting Properties of Waxy Wheat Flours

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    Citation: Purna, S. K. G., Shi, Y. C., Guan, L., Wilson, J. D., & Graybosch, R. A. (2015). Factors Governing Pasting Properties of Waxy Wheat Flours. Cereal Chemistry, 92(5), 529-535. doi:10.1094/cchem-10-14-0209-rWaxy wheat (Triticum aestivum L.) contains endosperm starch lacking in amylose. To realize the full potential of waxy wheat, the pasting properties of hard waxy wheat flours as well as factors governing the pasting properties were investigated and compared with normal and partial waxy wheat flours. Starches isolated from six hard waxy wheat flours had similar pasting properties, yet their corresponding flours had very different pasting properties. The differences in pasting properties were narrowed after endogenous alpha-amylase activity in waxy wheat flours was inhibited by silver nitrate. Upon treatment with protease, the extent of protein digestibility influenced the viscosity profile in waxy wheat flours. Waxy wheat starch granules swelled extensively when heated in water and exhibited a high peak viscosity, but they fragmented at high temperatures, resulting in more rapid breakdown in viscosity. The extensively swelled and fragmented waxy wheat starch granules were more susceptible to a-amylase degradation than normal wheat starch. A combination of endogenous a-amylase activity and protein matrix contributed to a large variation in pasting properties of waxy wheat flours

    XO-2b: Transiting Hot Jupiter in a Metal-rich Common Proper Motion Binary

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    We report on a V=11.2 early K dwarf, XO-2 (GSC 03413-00005), that hosts a Rp=0.98+0.03/-0.01 Rjup, Mp=0.57+/-0.06 Mjup transiting extrasolar planet, XO-2b, with an orbital period of 2.615857+/-0.000005 days. XO-2 has high metallicity, [Fe/H]=0.45+/-0.02, high proper motion, mu_tot=157 mas/yr, and has a common proper motion stellar companion with 31" separation. The two stars are nearly identical twins, with very similar spectra and apparent magnitudes. Due to the high metallicity, these early K dwarf stars have a mass and radius close to solar, Ms=0.98+/-0.02 Msolar and Rs=0.97+0.02/-0.01 Rsolar. The high proper motion of XO-2 results from an eccentric orbit (Galactic pericenter, Rper<4 kpc) well confined to the Galactic disk (Zmax~100 pc). In addition, the phase space position of XO-2 is near the Hercules dynamical stream, which points to an origin of XO-2 in the metal-rich, inner Thin Disk and subsequent dynamical scattering into the solar neighborhood. We describe an efficient Markov Chain Monte Carlo algorithm for calculating the Bayesian posterior probability of the system parameters from a transit light curve.Comment: 14 pages, 10 Figures, Accepted in ApJ. Negligible changes to XO-2 system properties. Removed Chi^2 light curve analysis section, and simplified MCMC light curve analysis discussio

    Pathologic gene network rewiring implicates PPP1R3A as a central regulator in pressure overload heart failure

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    Heart failure is a leading cause of mortality, yet our understanding of the genetic interactions underlying this disease remains incomplete. Here, we harvest 1352 healthy and failing human hearts directly from transplant center operating rooms, and obtain genome-wide genotyping and gene expression measurements for a subset of 313. We build failing and non-failing cardiac regulatory gene networks, revealing important regulators and cardiac expression quantitative trait loci (eQTLs). PPP1R3A emerges as a regulator whose network connectivity changes significantly between health and disease. RNA sequencing after PPP1R3A knockdown validates network-based predictions, and highlights metabolic pathway regulation associated with increased cardiomyocyte size and perturbed respiratory metabolism. Mice lacking PPP1R3A are protected against pressure-overload heart failure. We present a global gene interaction map of the human heart failure transition, identify previously unreported cardiac eQTLs, and demonstrate the discovery potential of disease-specific networks through the description of PPP1R3A as a central regulator in heart failure

    Bilateral Assessment of Functional Tasks for Robot-assisted Therapy Applications

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    This article presents a novel evaluation system along with methods to evaluate bilateral coordination of arm function on activities of daily living tasks before and after robot-assisted therapy. An affordable bilateral assessment system (BiAS) consisting of two mini-passive measuring units modeled as three degree of freedom robots is described. The process for evaluating functional tasks using the BiAS is presented and we demonstrate its ability to measure wrist kinematic trajectories. Three metrics, phase difference, movement overlap, and task completion time, are used to evaluate the BiAS system on a bilateral symmetric (bi-drink) and a bilateral asymmetric (bi-pour) functional task. Wrist position and velocity trajectories are evaluated using these metrics to provide insight into temporal and spatial bilateral deficits after stroke. The BiAS system quantified movements of the wrists during functional tasks and detected differences in impaired and unimpaired arm movements. Case studies showed that stroke patients compared to healthy subjects move slower and are less likely to use their arm simultaneously even when the functional task requires simultaneous movement. After robot-assisted therapy, interlimb coordination spatial deficits moved toward normal coordination on functional tasks

    Consumer Perspectives on Genetic Testing for Psychiatric Disorders: The Attitudes of Veterans with Posttraumatic Stress Disorder and Their Families

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    The perspectives of patients with posttraumatic stress disorder (PTSD) on genetic research have not yet been investigated in the genetics research literature. To provide a basis for research on attitudes toward genetic research in PTSD, we surveyed the U.S. Military Afghanistan/Iraq-era veterans with PTSD and their social support companions to investigate the attitudes and knowledge about genetics and genetic testing. One hundred forty-six veterans (76 with PTSD and 70 without PTSD) participated in this study. Each veteran participant had a corresponding companion (primarily spouses, but also relatives and friends) who they identified as a primary member of their social support network. Participants and companions completed self-report measures on knowledge of genetics and attitudes toward genetic testing for PTSD. Results indicated that, relative to veterans without PTSD, veterans with PTSD had similar levels of genetic knowledge, but less-favorable attitudes toward genetic testing. Differences persisted after controlling for age and genetics knowledge. No differences between companions of those with and without PTSD were observed. Results suggest that the perspective of those with PTSD regarding genetic testing is in need of further investigation, especially if potentially beneficial genetic testing for PTSD is to be utilized in the target population
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