2,327 research outputs found
Dietary supplementation of essential oils in dairy cows: evidence for stimulatory effects on nutrient absorption
Results of recent in vitro experiments suggest that essential oils (EO) may not only influence ruminal fermentation but also modulate the absorption of cations like Na+, Ca2+ and NH4+ across ruminal epithelia of cattle and sheep through direct interaction with epithelial transport proteins, such as those of the transient receptor potential family. The aim of the current study was to examine this hypothesis by testing the effect of a blend of essential oils (BEO) on cation status and feed efficiency in lactating dairy cows. In the experiment, 72 dairy cows in mid-to-end lactation were divided into two groups of 36 animals each and fed the same mixed ration with or without addition of BEO in a 2×2 cross-over design. Feed intake, milk yield and composition, plasma and urine samples were monitored. Feeding BEO elevated milk yield, milk fat and protein yield as well as feed efficiency, whereas urea levels in plasma and milk decreased. In addition, plasma calcium levels increased significantly upon BEO supplementation, supporting the hypothesis that enhanced cation absorption might contribute to the beneficial effects of these EO
Stability of resilience in times of the COVID‐19 pandemic
There is disagreement among researchers regarding the conceptualization of resilience as a dynamic state or stable trait. Aiming to shed light on the state-versus-trait debate, we explored the stability and construct validity of four of the most frequently utilized state or trait resilience scales in a longitudinal assessment. Additionally, we examined the predictive validity of these scales. Our study was conducted before and during the COVID-19 pandemic, which served as collectively experienced adversity. Correlations among the resilience scales and among resilience scales and Big Five personality traits were strong. All except one scale showed high test-retest correlations. Experience of an additional critical life event during the pandemic led to an increase in resilience. Other than in cross-sectional studies, associations between resilience and psychological distress were weak, because personality and baseline psychological distress were controlled for. Nevertheless, next to personality, resilience explained additional variance in distress change. Our results show relatively high stability of resilience overall. Yet, they also confirm dynamic resilience features, suggesting that resilience change occurs with significant adversity, leading to improved adaptation. To gauge the true association between resilience and mental health, baseline levels of these variables as well as personality traits should be considered
The future of genetic testing for drug response
The effect of variation in genes coding for drug targets and for the enzymes involved in drug metabolism has highlighted the genetic component of drug response. Drug response can be likened to a complex, multifactorial genetic trait, and the study of its genetic variation, termed pharmacogenetics, is analogous to the study of complex genetic disease in terms of the questions posed and the analytical possibilities. Just as DNA variants are associated with specific disease predispositions, so will they be associated with individual response to certain drugs. The testing for drug response is following the same route as the genetic testing for inherited disorders, and has reached the stage where genome-wide analysis, as opposed to the analysis of single genes, is a reality. In this article, we will discuss some of the technical advances that facilitate such analyses, leading to faster and more extensive diagnostic capabilities
Assessing the Effective Energy for Magnetic Forming Processes by Means of Measurements and Numerical Calculation
The efficiency of magnetic sheet metal forming processes is strongly depending on the facility s overall design. This mainly includes the geometric layout of forming tool, work piece and matrix but, however, will also expect the energy storage device being taken into consideration. Apart from field theoretic models the energy storage is describable by its terminal traits which the electric load - tool coil and work piece - is connected to. The paper presents a measuring method for the tool coil s terminal quantities, current i(t) and voltage u(t), which are used to provide the electric power p(t) being transferred to the load. Thus, it is possible to determine the entire energy which is dissipated by the work piece, provided that the coil s resistance is known. Besides the measurement, this approach is supported by numerical calculation intending to take a closer look at the inner losses of the work piece which are not accessible from measuring the system s terminal traits directly. Dividable into separate parts of the total energy, this information is applied to assess the forming process by means of the facility s energetic performance and to draw an overall energy balance
Word Processors with Line-Wrap: Cascading, Self-Organized Criticality, Random Walks, Diffusion, Predictability
We examine the line-wrap feature of text processors and show that adding
characters to previously formatted lines leads to the cascading of words to
subsequent lines and forms a state of self-organized criticality. We show the
connection to one-dimensional random walks and diffusion problems, and we
examine the predictability of catastrophic cascades.Comment: 6 pages, LaTeX with RevTeX package, 4 postscript figures appende
Resilience and personality as predictors of the biological stress load during the first wave of the Covid-19 pandemic in Germany
Since the Covid-19 outbreak, pandemic-specific stressors have potentiated the-already severe-stress load across the world. However, stress is more than an adverse state, and chronic exposure is causally involved in the development of mental and physical disease. We ask the question whether resilience and the Big Five personality traits predict the biological stress response to the first lockdown in Germany. In a prospective, longitudinal, observational study, N = 80 adult volunteers completed an internet-based survey prior to the first Covid-19-related fatality in Germany (T0), during the first lockdown period (T1), and during the subsequent period of contact restrictions (T2). Hair strands for the assessment of systemic cortisol and cortisone levels were collected at T2. Higher neuroticism predicted higher hair cortisol, cortisone and subjective stress levels. Higher extraversion predicted higher hair cortisone levels. Resilience showed no effects on subjective or physiological stress markers. Our study provides longitudinal evidence that neuroticism and extraversion have predictive utility for the accumulation of biological stress over the course of the pandemic. While in pre-pandemic times individuals high in neuroticism are typically at risk for worse health outcomes, extraverted individuals tend to be protected. We conclude that, in the pandemic context, we cannot simply generalize from pre-pandemic knowledge. Neurotic individuals may currently suffer due to their general emotional lability. Extraverted individuals may primarily be socially stressed. Individualized stress management programs need to be developed, and offered in a lockdown-friendly format, to minimize the stress burden caused by Covid-19 or future pandemics and to protect the most severely affected individuals from the development of stress-associated disease
Self-organized criticality in a rice-pile model
We present a new model for relaxations in piles of granular material. The
relaxations are determined by a stochastic rule which models the effect of
friction between the grains. We find power-law distributions for avalanche
sizes and lifetimes characterized by the exponents and
, respectively. For the discharge events, we find a
characteristic size that scales with the system size as , with . We also find that the frequency of the discharge events
decrease with the system size as with .Comment: 4 pages, RevTex, multicol, epsf, rotate (sty files provided). To
appear Phys. Rev. E Rapid Communication (Nov or Dec 96
PHENIX measurement of jet properties and their modification in heavy-ion collisions
The properties of jets produced in p+p, d+Au and Au+Au collisions at
sqrt{s_NN}=200 GeV are studied using the method of two particle correlations.
The trigger particle is assumed to be a leading particle from a high p_T jet
while the associated particle is assumed to come from either the same jet or
the away jet. From the angular width and yield of the same and away side
correlation peaks, the parameters characterizing the jet properties are
extracted.Comment: 4 pages, 3 figures, contribution to the proceedings of the 17th
International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions
(Quark Matter, Oakland, January 11-17, 2004). To appear in the proceedings
(Journal of Physics G
Avalanche statistics of sand heaps
Large scale computer simulations are presented to investigate the avalanche
statistics of sand piles using molecular dynamics. We could show that different
methods of measurement lead to contradicting conclusions, presumably due to
avalanches not reaching the end of the experimental table.Comment: 6 pages, 4 figure
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