Effects of Inorganic and Organic Selenium Supplementation on Blood and Milk Selenium Concentration in Dairy Cows

Selenium is an important trace element in the nutrition of dairy cows because it prevents oxidative damages of tissue and in that way protects the animals from the incidence of various disorders. Addition of various levels of selenium in food leads to its increase in the milk what is important for postnatal calves development in which in the first weeks of life the milk is the only source of selenium. Into the food for dairy cows the inorganic selenium is added in the forms of – sodium selenite or sodium selenate (SS) or organic selenium – seleniium-enriched yeast (SY). Numerous studies have shown that organic selenium (SY) added into food for dairy cows provides better bioavailability than inorganic selenium (SS), hence the content of selenium in blood and milk of cows fed organic form of selenium is higher than in the inorganic selenium. The opinions about the effect of organic selenium on the activity of seleno-enzyme glutathione peroxidase (GPx) have not been reconciled yet. Adding selenium into food for dairy cows has no effect on the quantity of produced milk nor on the milk composition (proteins, fats and lactose). Selenium reduces the number of somatic cells in milk and in that way prevents the occurrence of the disease of mammary gland

Optimal Selection of Rotor Bar Number in Multiphase Cage Induction Motors

Rules for the selection of rotor bar numbers which minimize current and torque ripples are derived in this paper for a general symmetrical multiphase cage induction machine with prime phase number and integral slot winding. Analytically obtained expressions for optimal rotor bar number selection are validated by means of totally independent simulations, one based on a parameterized winding function (PWF) model of the induction machine and the other employing time-stepping finite element analysis (TSFEA). As a case study, five-phase four-pole cage induction motors with forty stator slots and different number of rotor bars are comparatively analyzed. Results obtained from the PWF model are in excellent accordance with those independently obtained by TSFEA and both confirm the correctness of the proposed selection criteria. The practical motivation of the study is that an incorrect selection of rotor bar number can lead to parasitic torques of significant amplitude and, presently, there are no general rules available in the literature which may guide designers towards an optimal design choice for a general number of phases

The Effect of Supplementation on Selenium and Zinc Content in Blood and Milk of Dairy Cows

Milk is an important source of microelements for calves during the suckling period as well as in human nutrition. Concentration of trace elements in blood and their secretion via milk can significantly change depending on food intake and composition. Proper control of selenium and zinc content in blood and in milk can improve the status of these microelements, so that the occurrence of deficiency or excessive quantity due to their increased intake can be prevented. This paper presents the results of the study on the concentration of selenium and zinc in the blood and milk of diary cows whose rations have been supplemented by organic forms of selenium (0.2 mg/kg DM) and zinc (40 mg/kg DM) during the last ten days of dry period and early lactation. Supplemented cows in trial groups A and B achieved significatly higher concentrations of these microelements in blood (Se 186.70±8.50 µg/L vs. 118.80±7.05 µg/L), blood serum (Zn 1204.70±109.5 µg/L vs. 1095.40±130.2 µg/L) and milk (Se 57.30±8.05 vs. 21.30±4.60 µg/L; Zn 2893.90±120.15 µg/L vs. 1952.10±130.50 µg/L) on 60th day postpartum compared to non-supplemented control

Ratio of maximum hamstring torque to maximum quadriceps torque in professional basketball and soccer players

Purpose: The aim of the study was to determine the differences between football players and basketball players in the mean absolute values of maximum torque flexors and extensors, ratio of maximum hamstring torque to maximum quadriceps torque dominant (DOM) non-dominant (ND) leg and differences in bilateral imbalance of flexor muscles and knee extensors. Material and methods: The research included a sample of 39 professional athletes. The first subsample included 19 professional basketball players while the second subsample included 20 professional soccer players. Results: Based on the results of the torques of the extensors in the knee joint of the DOM and ND legs, it was established that there is no statistically significant difference between basketball players and football players. However, a statistically significant difference was found in the torque flexors of the knee joint DOM (p≤0.01) and ND (p≤0.00) of the leg between basketball players and football players. On the other hand, the results of the research indicate that the difference between basketball players and football players in the ratio of Hamstrings peak torque to Quadriceps peak torque was recorded only in the ND leg (p≤0.02), while the difference in the DOM leg is not statistically significant. The results of our study indicate that basketball players have a higher percentage of imbalances compared to football players, especially in m. hamstrings. Conclusion: This study provides normative data on populations specific to soccer and basketball, but does not provide evidence of the ability of the isokinetic assessment of lower extremity muscle strength to predict injuries to football players and basketball players

Preemptive analgesic effect of intrathecal applications of neuroactive steroids in a rodent model of post-surgical pain: Evidence for the role of T-type calcium channels

Preemptive management of post-incisional pain remains challenging. Here, we examined the role of preemptive use of neuroactive steroids with activity on low-voltage activated T-type C

Near-complete suppression of harmonic currents in SPMSMs caused by back emf and dead time

This paper introduces a novel algorithm for suppression of phase current harmonics in three-phase sinusoidal surface mounted permanent magnet synchronous machines (SPMSMs) caused by non-ideal back-emf waveform and dead-time effects. Proposed feedback acquisition chain obtains an exact information on all the relevant harmonics within each period of the fundamental. Design of the harmonic current controller based on the internal model control principle is given. The paper outlines the relevant details of implementation and the results of verification performed by both computer simulations and experimentally, using a laboratory prototype machine. Experimental results, obtained in presence of non-sinusoidal back-emf and with erroneous dead-time compensation, prove the ability of the proposed solution to remove the stator current harmonics quickly, in just two fundamental periods, and thus eliminate torque ripple

Optimal Selection of Rotor Bar Number for Minimizing Torque and Current Pulsations due to Rotor Slot Harmonics in Three-Phase Cage Induction Motors

The paper develops a method to choose the number of rotor bars in order to eliminate rotor slot harmonics in stator current spectrum and pulsation torques that are their consequence. Mains-fed, three-phase cage induction motors with the most common number of pole pairs and number of stator slots, that result in integer slot winding, are analyzed. The analysis is based on the recently derived general rule for optimal selection of rotor bars, valid for symmetrical multiphase machine with prime number of phases and integer slot stator winding. As a tool for validation of analytically predicted results, parameterized winding function (PWF) model is used. Electromagnetic torque ripple factor is used as a measure of goodness of the number of rotor bar selection. The practical motivation of the study is an attempt to supersede the many existing rules for rotor bar number selection that, depending on the source, may be different, and provide a unified general approach to the problem. One of the main findings derived in the paper is ascertainment that increasing the number of pole pairs increases the degree of freedom in choosing the proper number of rotor bars. The same applies when the number of motor phases increases

Differential effects of the novel neurosteroid hypnotic (3β,5β,17β)-3-hydroxyandrostane-17-carbonitrile on electroencephalogram activity in male and female rats

BACKGROUND: We recently showed that a neurosteroid analogue, (3β,5β,17β)-3-hydroxyandrostane-17-carbonitrile (3β-OH), induced hypnosis in rats. The aim of the present study was to evaluate the hypnotic and anaesthetic potential of 3β-OH further using electroencephalography. METHODS: We used behavioural assessment and cortical electroencephalogram (EEG) spectral power analysis to examine hypnotic and anaesthetic effects of 3β-OH (30 and 60 mg kg RESULTS: We found dose-dependent sex differences in 3β-OH-induced hypnosis and EEG changes. Both male and female rats responded similarly to i.p. 3β-OH 30 mg kg CONCLUSIONS: Based on its behavioural effects and EEG signature, 3β-OH is a potent hypnotic in rats, with female rats being more sensitive than male rats

Ectopic Wnt/Beta–Catenin Signaling Induces Neurogenesis in the Spinal Cord and Hindbrain Floor Plate

The most ventral structure of the developing neural tube, the floor plate (FP), differs in neurogenic capacity along the neuraxis. The FP is largely non-neurogenic at the hindbrain and spinal cord levels, but generates large numbers of dopamine (mDA) neurons at the midbrain levels. Wnt1, and other Wnts are expressed in the ventral midbrain, and Wnt/beta catenin signaling can at least in part account for the difference in neurogenic capacity of the FP between midbrain and hindbrain levels. To further develop the hypothesis that canonical Wnt signaling promotes mDA specification and FP neurogenesis, we have generated a model wherein beta–catenin is conditionally stabilized throughout the FP. Here, we unambiguously show by fate mapping FP cells in this mutant, that the hindbrain and spinal cord FP are rendered highly neurogenic, producing large numbers of neurons. We reveal that a neurogenic hindbrain FP results in the altered settling pattern of neighboring precerebellar neuronal clusters. Moreover, in this mutant, mDA progenitor markers are induced throughout the rostrocaudal axis of the hindbrain FP, although TH+ mDA neurons are produced only in the rostral aspect of rhombomere (r)1. This is, at least in part, due to depressed Lmx1b levels by Wnt/beta catenin signaling; indeed, when Lmx1b levels are restored in this mutant, mDA are observed not only in rostral r1, but also at more caudal axial levels in the hindbrain, but not in the spinal cord. Taken together, these data elucidate both patterning and neurogenic functions of Wnt/beta catenin signaling in the FP, and thereby add to our understanding of the molecular logic of mDA specification and neurogenesis