Feeding Methionine to Laying Hens in Drinking Water

The present study intended to demonstrate the appetite of laying hens for methionine when offered as a choice in drinking water. Methionine, the first limiting amino acid in practical layer diets is currently provided in the feed in constant amounts. In contrast to this arguable practice, its addition to the drinking water would enable the birds to consume amounts according to their actual methionine requirements. Ten experiments were performed to investigate the conditions of this way of delivery. For the first 5 experiments ISA Brown, for the second 5 Lohmann layers were used. 1) Two preliminary tests determined that a minimum of 140 g/kg dietary crude protein (CP) is necessary for normal egg production of at least 90% of commercial target values, and that the typical feed intake / water intake ratio is 1:1.44. 2) Initially, the appetite of layers for methionine in drinking water was investigated by subjecting them to the combinations of feed adequate or deficient in methionine, and plain or methionine-treated water. Neither cues nor training were used. In the choice situation, the birds could not express an appetite for treated water. 4) Colour cues and training of the birds were introduced to enable birds to express an appetite for methionine-treated water. The choices made in favour of treated water were 98.9% in a period of 5 days, and 93.9% when the position of the bottles was swapped. 5) Methionine deficiency resulted in decreased feed and water intake which were restored when methionine was added to the diet. The way of delivery (in water or feed) was insignificant in this effect, indicating that the source of methionine does not influence normal appetite. 6) Next, the birds' ability to regulate their intake of methionine was investigated. The introduction of an additional colour was expected to avoid the association of plain water with the effects of methionine deficiency, thus in the choice situation, neither the treated nor the plain water had a "history" of causing discomfort to the birds previously. Yet, the birds did not stop the consumption of the treated water even when they had satisfied their methionine requirements, indicating that they can not regulate methionine intake. 7) The detection threshold for methionine was investigated by using different levels of methionine in the drinking water in combination with methionine- deficient feed. It was found that the minimum level of methionine in drinking water for which birds can express appetite is at least 0.025%. 8) The investigations on the metabolic effects of methionine deficiency showed that the birds respond to the deficiency by reducing their feed intake, which decrease becomes significant after eight hours. 9) The hypothesis was examined that giving a methionine-deficient diet in the last 5 hours of the feeding period, the birds will reduce their feed intake in the following morning even if they are fed on an adequate diet that time. It is indicated that the time of receiving a methionine-deficient diet is closely associated with the time of feed intake depression. 10) Determination of the threshold period of training of the birds showed that the using of an 8-hours exposure time resulted in a more than 90% of choices for methionine-treated water. 11) The memory of the birds was tested once after a period of 15 days and again after a period of 45 days on commercial diet. In the subsequent choice situation, birds receiving the 8-hours treatment showed a strong preference for methionine indicating that birds memory last at least 45 days. 12) It was shown that 2.1 g/kg methionine in the feed was deficient for almost all the birds. Birds receiving adequate or nearly adequate amounts of methionine do not feel the physiological effects of deficiency. These birds do not select methionine treated water in a choice situation. The main conclusions of the study are that the source of methionine is insignificant in terms of feed intake, and that layers can express an appetite for methionine in drinking water with the aid of a cue and adequate training

Entropy-based goodness-of-fit tests for multivariate distributions

Entropy is one of the most basic and significant descriptors of a probability distribution. It is still a commonly used measure of uncertainty and randomness in information theory and mathematical statistics. We study statistical inference for Shannon and Rényi’s entropy-related functionals of multivariate Gaussian and Student-t distributions. This thesis investigates three themes. First, we provide a non-parametric test of goodness-of-fit for a class of multivariate generalized Gaussian distributions based on maximum entropy principle via using the k-th nearest neighbour (NN) distance estimator of the Shannon entropy. Its asymptotic unbiasedness and consistency are demonstrated. Second, we show a class of estimators of the Rényi entropy based on an independent identical distribution sample drawn from an unknown distribution f on R m. We focus on the maximum Rényi entropy principle for multivariate Student-t and Pearson type II distributions. We also consider the entropy-based test for multivariate Student-t distribution using the k-th NN distances estimator of entropy and employ the properties of entropy estimators derived from NN distances. Third, we introduce a new classes of unimodal rotational invariant directional distributions, which generalize von Mises-Fisher distribution. We propose three types of distributions in which one of them represents the axial data. We provide all of the formula together with a short computational study of parameter estimators for each new type via the method of moments and method of maximum likelihood. We also offer the goodness-of-fit test to detect that the sample entries follow one of the introduced generalized von Mises-Fisher distribution based on the maximum entropy principle using the k-th NN distances estimator of Shannon entropy and to prove its L2 -consistence

IMECE2011-63861 PROPER ORTHOGONAL DECOMPOSITON ANALYSIS OF JAVA FLOWS FOR CROSS-FLOW CONDITIONS

ABSTRACT Jet and Vortex Actuator (JaVA) is a zero-net-mass flux device for active flow control of boundary layers and transition. JaVA produces various jets which can be used to delay flow separation or to "steer" the boundary layer velocity profile. In this study, numerical simulations of JaVA-boundary layer interactions are analyzed using Proper Orthogonal Decomposition (POD). JaVA-induced flow regimes are governed by the plate width (b), the amplitude (a) and the operating frequency (f). In this study the frequency is changed between 2/3 Hz and 8/3 Hz keeping the plate width and the amplitude constant. A commercial finite-volume-based unsteady, laminar, incompressible Navier-Stokes solver has been used to study the flow fields generated by JaVA. Then, POD is applied to time dependent snapshots of velocity fields at each operating frequency. The POD modes revealed the behavior of the flat plate boundary layer under the effect of active flow control. Traveling modes can be captured in the successive modes for high frequencies

Studying dynamic stress effects on the behaviour of THP-1 cells by microfluidic channels

Atherosclerosis is a long-term disease process of the vascular system that is characterized by the formation of atherosclerotic plaques, which are inflammatory regions on medium and large-sized arteries. There are many factors contributing to plaque formation, such as changes in shear stress levels, rupture of endothelial cells, accumulation of lipids, and recruitment of leukocytes. Shear stress is one of the main factors that regulates the homeostasis of the circulatory system; therefore, sudden and chronic changes in shear stress may cause severe pathological conditions. In this study, microfluidic channels with cavitations were designed to mimic the shape of the atherosclerotic blood vessel, where the shear stress and pressure difference depend on design of the microchannels. Changes in the inflammatory-related molecules ICAM-1 and IL-8 were investigated in THP-1 cells in response to applied shear stresses in an continuous cycling system through microfluidic channels with periodic cavitations. ICAM-1 mRNA expression and IL-8 release were analyzed by qRT-PCR and ELISA, respectively. Additionally, the adhesion behavior of sheared THP-1 cells to endothelial cells was examined by fluorescence microscopy. The results showed that 15 Pa shear stress significantly increases expression of ICAM-1 gene and IL-8 release in THP-1 cells, whereas it decreases the adhesion between THP-1 cells and endothelial cells

The entropy based goodness of fit tests for generalized von Mises-Fisher distributions and beyond

Abstract We introduce some new classes of unimodal rotational invariant directional distributions, which generalize von Mises–Fisher distribution. We propose three types of distributions, one of which represents axial data. For each new type we provide formulae and short computational study of parameter estimators by the method of moments and the method of maximum likelihood. The main goal of the paper is to develop the goodness of fit test to detect that sample entries follow one of the introduced generalized von Mises–Fisher distribution based on the maximum entropy principle. We use kth nearest neighbour distances estimator of Shannon entropy and prove its L 2 -consistency. We examine the behaviour of the test statistics, find critical values and compute power of the test on simulated samples. We apply the goodness of fit test to local fiber directions in a glass fibre reinforced composite material and detect the samples which follow axial generalized von Mises–Fisher distribution. Acknowledgment The authors are grateful to Prof. Katja Schladitz for the help with the real data, Martin Gurka and Sebastian Nissle (Institut für Verbundwerkstoffe, Kaiserslautern) for permission to reuse the tomographic images, Prof. Claudia Redenbach for providing the data set of fiber directions. We would like to thank the Editor, Domenico Marinucci, and the anonymous referee for their insightful comments and suggestions, that led to an improvement of a previous version of this work

Anti-Inflammatory and Antinociceptive Effects of Salbutamol on Acute and Chronic Models of Inflammation in Rats: Involvement of an Antioxidant Mechanism

The possible role of β-2 adrenergic receptors in modulation of inflammatory and nociceptive conditions suggests that the β-2 adrenergic receptor agonist, salbutamol, may have beneficial anti-inflammatory and analgesic effects. Therefore, in this study, we induced inflammatory and nociceptive responses with carrageenan-induced paw edema or cotton-pellet-induced granuloma models, both of which result in oxidative stress. We hypothesized that salbutamol would prevent inflammatory and nociceptive responses by stimulating β-2 adrenergic receptors and the prevention of generation of ROS during the acute inflammation process in rats. Both doses of salbutamol used in the study (1 and 2 mg/kg) effectively blocked the acute inflammation and inflammatory nociception induced by carrageenan. In the cotton-pellet-induced granuloma test, both doses of salbutamol also significantly decreased the weight of granuloma tissue on the cotton pellets when compared to the control. Anti-inflammatory and analgesic effects of salbutamol were found to be comparable with those of indomethacin. Salbutamol decreased myeloperoxidase (MPO) activity and lipid peroxidation (LPO) level and increased the activity of superoxide dismutase (SOD) and level of glutathione (GSH) during the acute phase of inflammation. In conclusion, salbutamol can decrease acute and chronic inflammation, possibly through the stimulation of β-2 adrenergic receptors. This anti-inflammatory effect may be of significance in asthma treatment, where inflammation also takes part in the etiopathology. This study reveals that salbutamol has significant antioxidative effects, which at least partially explain its anti-inflammatory capabilities. These findings presented here may also shed light on the roles of β-2 adrenergic receptors in inflammatory and hyperalgesic conditions

Ultrafast charge dynamics in trap-free and surface-trapping colloidal quantum dots

Ultrafast transient absorption spectroscopy is used to study subnanosecond charge dynamics in CdTe colloidal quantum dots. After treatment with chloride ions, these can become free of surface traps that produce nonradiative recombination. A comparison between these dots and the same dots before treatment enables new insights into the effect of surface trapping on ultrafast charge dynamics. The surface traps typically increase the rate of electron cooling by 70% and introduce a recombination pathway that depopulates the conduction band minimum of single excitons on a subnanosecond timescale, regardless of whether the sample is stirred or flowed. It is also shown that surface trapping significantly reduces the peak bleach obtained for a particular pump fluence, which has important implications for the interpretation of transient absorption data, including the estimation of absorption cross‐sections and multiple exciton generation yields

Piezoresistivity and piezopermittivity of cement-based sensors under quasi-static stress and changing moisture

Integrated cement-based sensors offer an economic alternative to extrinsic sensors for health monitoring applications in concrete structures due to their high strength to cost ratio, geometrical versatility, low shrinkage, and natural compatibility. Nonetheless, their performance under in-service conditions were in lack of investigations. While the piezoresistivity (change in resistance with stress) has been commonly used for mechanical sensing, the piezopermittivity (change in capacitive reactance with stress) is rarely characterized. Exploiting the high relative permittivity and electrical conductivity of carbon fibre reinforced cement-based sensors, this study investigates the piezoresistivity and piezopermittivity under changing stress and moisture using electrochemical impedance spectroscopy (EIS). Two types of sensors were evaluated: one containing 0.5 vol% of carbon fibres whose electrical conductivity was ionically dominant, and another with electronically dominant (1.2 vol% of carbon fibres) conductivity. Results highlighted that the piezopermittivity is “moisture content-dominant” whilst the piezoresistivity is “fibre content-dominant”. As the moisture content decreased, the sensitivity of piezopermittivity for both sensor types decreased, while the sensitivity of piezoresistivity decreased for the ionically dominant sensor but increased for the electronically dominant sensor. The piezoresistivity of the electronically dominant sensor was less sensitive than piezopermittivity at a water saturation of 80%. Conversely, the piezoresistivity of the ionically dominant sensor was more sensitive than piezopermittivity at the tested water saturations ≤ 80%. For the first time, this study presents the combined effects of moisture and fibre content on the pressure sensitive response of cement-based sensors through a dual-phase (i.e., piezoresistivity and piezopermittivity) EIS interpretation technique, providing valuable information to benefit further behaviour prediction and single-effect recognition in the field scenario where the sensors are subject to simultaneous environmental effects causing moisture variations such as temperature and humidity variations, freeze-thawing, and so on