33 research outputs found
Hydrated lime matrix decreases ruminal biohydrogenation of flaxseed fatty acids
Omega-3 fatty acids are essential nutrients for humans, but dietary intake of these
nutrients by many Americans is inadequate due to low consumption of omega-3-rich
foods such as fish, walnuts, and flaxseed. In contrast, per capita consumption of red
meat is relatively high, but these products normally contain only small amounts of
omega-3 fatty acids. Feeding cattle diets that contain omega-3 fatty acids has consistently
increased the proportion of the desirable fats that accumulate in beef. Unfortunately,
the proportion of dietary omega-3 fats that are deposited into beef tissues is
relatively low, because microorganisms within the rumen biohydrogenate the unsaturated
omega-3 fatty acids extensively to produce the saturated fats that are characteristic
of beef fat. Encapsulation of fats has been proposed as a method for improving efficiency
of transfer of omega-3 fats into beef. Encapsulation processes apply a protective
barrier on the surface of fats or fat-containing feeds, which theoretically decreases fats’
susceptibility to microbial biohydrogenation. Protective coatings must remain intact to
retain their functionality, and physical damage to the coatings that occurs with normal
handling can result in poor efficacy because the core material is exposed to microorganisms
in the rumen. Embedding feed particles within a homogeneous protective matrix
constitutes a potentially useful alternative to protective surface barriers. The matrix is
created by mixing feed particles that are to be protected with a suitable matrix material
that is resistant to microbial digestion and subsequently forming the mixture into pills.
In cases where physical damage occurs, exposure of the core material is confined to the
broken surface, and the remainder of the matrix retains its ruminal stability.
The objective of this study was to determine if embedding flaxseed within a matrix of
hydrated dolomitic lime could be used as a method to decrease biohydrogenation of
polyunsaturated omega-3 fatty acids, thus improving efficiency of omega-3 fatty acids
absorption into the bloodstream
Examining the validity of the Athlete Engagement Questionnaire (AEQ) within a Portuguese sport setting
Sport psychology literature suggests that understanding engagement levels is pivotal to promote positive sporting experiences among athletes. The purpose of this study was to examine the psychometric properties of the Athlete Engagement Questionnaire among Portuguese sport athletes. Two distinct samples of Portuguese athletes from different competitive levels were collected, and the results of a confirmatory factor analysis demonstrated a good fit of the model to the data. A review of the psychometric properties indicated that all factors showed good composite reliability, convergent validity, and discriminant validity. In addition, a multi-groups analysis showed the invariance of the model in two independent samples providing evidence of cross validity. Implications of these results for scholars and coaches are discussed and guidelines for future studies are suggested
A connectome of the adult drosophila central brain
The neural circuits responsible for behavior remain largely unknown. Previous efforts have reconstructed the complete circuits of small animals, with hundreds of neurons, and selected circuits for larger animals. Here we (the FlyEM project at Janelia and collaborators at Google) summarize new methods and present the complete circuitry of a large fraction of the brain of a much more complex animal, the fruit fly Drosophila melanogaster. Improved methods include new procedures to prepare, image, align, segment, find synapses, and proofread such large data sets; new methods that define cell types based on connectivity in addition to morphology; and new methods to simplify access to a large and evolving data set. From the resulting data we derive a better definition of computational compartments and their connections; an exhaustive atlas of cell examples and types, many of them novel; detailed circuits for most of the central brain; and exploration of the statistics and structure of different brain compartments, and the brain as a whole. We make the data public, with a web site and resources specifically designed to make it easy to explore, for all levels of expertise from the expert to the merely curious. The public availability of these data, and the simplified means to access it, dramatically reduces the effort needed to answer typical circuit questions, such as the identity of upstream and downstream neural partners, the circuitry of brain regions, and to link the neurons defined by our analysis with genetic reagents that can be used to study their functions. Note: In the next few weeks, we will release a series of papers with more involved discussions. One paper will detail the hemibrain reconstruction with more extensive analysis and interpretation made possible by this dense connectome. Another paper will explore the central complex, a brain region involved in navigation, motor control, and sleep. A final paper will present insights from the mushroom body, a center of multimodal associative learning in the fly brain
A connectome and analysis of the adult Drosophila central brain
The neural circuits responsible for animal behavior remain largely unknown. We summarize new methods and present the circuitry of a large fraction of the brain of the fruit fly Drosophila melanogaster. Improved methods include new procedures to prepare, image, align, segment, find synapses in, and proofread such large data sets. We define cell types, refine computational compartments, and provide an exhaustive atlas of cell examples and types, many of them novel. We provide detailed circuits consisting of neurons and their chemical synapses for most of the central brain. We make the data public and simplify access, reducing the effort needed to answer circuit questions, and provide procedures linking the neurons defined by our analysis with genetic reagents. Biologically, we examine distributions of connection strengths, neural motifs on different scales, electrical consequences of compartmentalization, and evidence that maximizing packing density is an important criterion in the evolution of the fly’s brain
25 Years of Self-organized Criticality: Concepts and Controversies
Introduced by the late Per Bak and his colleagues, self-organized criticality (SOC) has been one of the most stimulating concepts to come out of statistical mechanics and condensed matter theory in the last few decades, and has played a significant role in the development of complexity science. SOC, and more generally fractals and power laws, have attracted much comment, ranging from the very positive to the polemical. The other papers (Aschwanden et al. in Space Sci. Rev., 2014, this issue; McAteer et al. in Space Sci. Rev., 2015, this issue; Sharma et al. in Space Sci. Rev. 2015, in preparation) in this special issue showcase the considerable body of observations in solar, magnetospheric and fusion plasma inspired by the SOC idea, and expose the fertile role the new paradigm has played in approaches to modeling and understanding multiscale plasma instabilities. This very broad impact, and the necessary process of adapting a scientific hypothesis to the conditions of a given physical system, has meant that SOC as studied in these fields has sometimes differed significantly from the definition originally given by its creators. In Bak’s own field of theoretical physics there are significant observational and theoretical open questions, even 25 years on (Pruessner 2012). One aim of the present review is to address the dichotomy between the great reception SOC has received in some areas, and its shortcomings, as they became manifest in the controversies it triggered. Our article tries to clear up what we think are misunderstandings of SOC in fields more remote from its origins in statistical mechanics, condensed matter and dynamical systems by revisiting Bak, Tang and Wiesenfeld’s original papers
Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study
A41 Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study
In: Addiction Science & Clinical Practice 2017, 12(Suppl 1): A4
A connectome and analysis of the adult Drosophila central brain
The neural circuits responsible for animal behavior remain largely unknown. We summarize new methods and present the circuitry of a large fraction of the brain of the fruit fly Drosophila melanogaster. Improved methods include new procedures to prepare, image, align, segment, find synapses in, and proofread such large data sets. We define cell types, refine computational compartments, and provide an exhaustive atlas of cell examples and types, many of them novel. We provide detailed circuits consisting of neurons and their chemical synapses for most of the central brain. We make the data public and simplify access, reducing the effort needed to answer circuit questions, and provide procedures linking the neurons defined by our analysis with genetic reagents. Biologically, we examine distributions of connection strengths, neural motifs on different scales, electrical consequences of compartmentalization, and evidence that maximizing packing density is an important criterion in the evolution of the fly's brain
Dosing with Lactipro decreases forage intake and manure output
High-concentrate diets consisting of cereal grains and grain byproducts have high
energy density compared with forage-based diets. To avoid digestive disorders, cattle
must be adapted to concentrates, which often entails feeding a series of step-up diets
that contain progressively less roughage over a 2- to 3-week period. This allows the
microbial population to adapt to fermentation of the starches and sugars that are present
in high-concentrate diets. If cattle are not properly adapted to concentrate-based
diets, lactic acid, which is produced by opportunistic starch-fermenting bacteria like
Streptococcus bovis, can accumulate, predisposing the animal to acidosis. Diets used
during the adaptation phase are by nature less digestible than the final finishing diet,
which results in increased manure output and suboptimal performance during the
adaptation period.
Lactipro, a relatively new probiotic drench containing the lactate-utilizing bacteria
Megasphaera elsdenii, has been utilized effectively to accelerate the adaptation of cattle
from roughages to concentrate-based diets. Our objective was to determine the impact
on diet digestibility and manure output in cattle dosed with Lactipro (MS Biotech,
Inc., Wamego, KS) and placed directly onto high-concentrate diets without prior
adaptation
Crude glycerin improves feed efficiency in finishing heifers
Crude glycerin is the principal byproduct of biodiesel production. The raw feedstocks,
animal fats and vegetable oils, yield approximately 90 lb of biodiesel and 10 lb of crude
glycerin for each 100 lb of input. When ingested by cattle, glycerin has two major fates:
(1) direct absorption by the rumen epithelium, and (2) fermentation by microorganisms
within the rumen to generate volatile fatty acid, mainly propionate. Using glycerin
in feedlot cattle diets has become common, particularly as a component of liquid feed
supplements.
We have evaluated the use of crude glycerin in cattle diets in previous studies and generally
have observed positive effects on dry matter intake and feed efficiency when fed
up to 8% of the diet on a dry matter basis. Crude glycerin can be highly variable in its
composition, however, containing varying proportions of residual alcohol, soaps, and
salts. Our focus in the present experiment was on the sodium content of crude glycerin.
We hypothesized that the high concentration of sodium in glycerin, when combined
with salt that normally is incorporated into feedlot diets, would result in abnormally
high levels of sodium that could have deleterious consequences for feed consumption.
The objective of this study was to evaluate feedlot performance and carcass characteristics
of finishing heifers fed diets containing high levels of crude glycerin in the presence
and absence of added salt
Influence of Linpro and dietary copper on feedlot cattle performance, carcass characteristics, and fatty acid composition of beef
Human diets often contain high levels of saturated fatty acids that can have deleterious
health consequences such as obesity, diabetes, and heart disease. In contrast, omega-3
fatty acids, which are essential for human nutrition, are consumed at relatively low
levels despite of their positive effects on health. Natural sources of omega-3 fatty acids
include fresh legumes, cool-season grasses, flaxseed, and fish oil. In spite of the fact
that fresh forages often are a key part of the cattle diet, beef is a relatively poor source
of omega-3 fatty acids because of biohydrogenation, the action of microorganisms
in the rumen that convert polyunsaturated fatty acids, including the omega-3 fats,
into saturated fats. Previous research at Kansas State University has shown that feeding
cattle flax-based feeds can increase concentrations of omega-3 fatty acids in beef.
Researchers at Colorado State University have reported that elevated levels of dietary
copper can inhibit the biohydrogenation process to yield beef with greater proportions
of polyunsaturated fatty acids. Our objective was to evaluate whether feeding elevated
copper concentrations in conjunction with Linpro (O&T Farms; Regina, Saskatchewan,
Canada), a co-extruded blend of field peas and flaxseed, could be used to further
improve the levels of omega-3 fatty acids in beef