Delivery method and supplement consumption by grazing ruminants: a review

The effectiveness of supplementation programs is affected by the ability to reduce intake variation and to meet target supplement consumption. A review was made of factors affecting variation in individual animal consumption of supplement by grazing cattle and sheep, including supplement type and feeding method, animal dominance and social interactions, and forage availability. The effects of palatability were not included. The proportion of animals not consuming supplement is increased by limited trough space, small supplement allowance, self-fed supplements, neophobia to feed or feed delivery devices, and group feeding situations. Variation in individual animal supplement intake is increased by excessive trough space, limited supplement allowance, self-fed supplements, feed and feed delivery equipment neophobia, and individual feeding of supplements. Factors influencing the percentage of animals consuming the target amount of supplement need to be more clearly identified. There seems to be an optimum level of feeding competition that reduces intake variation and improves the proportion of animals consuming adequate amounts of supplement, but this optimum varies with the feeding situation.     

Rotatable liquid crystal waveplate

A photoresist well of size 60 × 60 × 15 μm³ has been used to confine a droplet of nematic liquid crystal to create a rotatable waveplate. The optical texture of the droplet between crossed polarisers is consistent with the nematic n-director running substantially along a diameter of the droplet and connecting two nematic defects on the curved edges of the droplet. Electric field induced azimuthal rotation of the axis of the nematic liquid crystal droplet has been demonstrated. At higher temperatures, 30 °C and above, the droplet is more circular in shape and can be switched to arbitrary rotation angles. At lower temperatures, 25 °C and below, the sides of the droplet are straightened by the interaction with the well walls and the switching tends to favour discrete orientations of the optic axis. The shape of the time–voltage switching response curve for rotation by an angle of 40° also depends on the temperature of the droplet. A switching time that is inversely proportional to the voltage squared results when the droplet is nearest to circular in shape.     

Prevalence estimation and validation of new instruments in psychiatric research: An application of latent class analysis and sensitivity analysis.

Prevalence and validation studies rely on imperfect reference standard (RS) diagnostic instruments that can bias prevalence and test characteristic estimates. The authors illustrate 2 methods to account for RS misclassification. Latent class analysis (LCA) combines information from multiple imperfect measures of an unmeasurable latent condition to estimate sensitivity (Se) and specificity (Sp) of each measure. With simple algebraic sensitivity analysis (SA), one uses researcher-specified RS misclassification rates to correct prevalence and test characteristic estimates and can succinctly summarize a range of scenarios with Monte Carlo simulation. The authors applied LCA to a validation study of a new substance use disorder (SUD) screener and a larger prevalence study. With a traditional validation study analysis in which an error-free RS (Structured Clinical Interview for DSM–IV Axis I Disorders [SCID]; M. H. First, R. L. Spitzer, M. Gibbon, & J. Williams, 1990) is assumed, the authors estimated the screener had 86% Se and 75% Sp. Validation study estimates from LCA were 91% Se, 81% Sp (screener), 73% Se, and 98% Sp (SCID). SA in the prevalence study suggested the prevalence of SUD was underestimated by 22% because SCID was assumed to be error-free. LCA and SA can assist investigators in relaxing the unrealistic assumption of perfect RSs in reporting prevalence and validation study results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Clinical and genetic analysis of a pedigree of a thirty-six-year-old familial Alzheimer''s disease patient

Distribution of apolipoprotein(apo) E4 and E3 in lipoproteins of serum with apoE4/E3 phenotype was analyzed. ApoE was eluted in two major peaks by gel chromatography; peak 1 and 2 corresponding to very- and intermediate-low density lipoprotein (VLDL + IDL) and high density lipoprotein2 (HDL2), respectively. ApoE in peak 1 (VLDL + IDL) consisted of monomers of 34 kDa, complexes with a high molecular weight (apoEs) of 100 kDa and with a small amount of apoE-AII complexes weighing 43 kDa. In contrast, apoE in peak 2 (HDL2) was composed mainly of apoE-AII complexes and apoEs complexes, and a small amount of monomers. Both apoE3 and E4 isoforms were detected in these peaks; E4 was more predominant in peak 1 while E3 was more predominant in peak 2. These findings suggest that different distributions of apoE3 and E4 in lipoprotein particles.     

Targeting the Water Network in Cyclin G-Associated Kinase (GAK) with 4-Anilino-quin(az)oline Inhibitors

Water networks within kinase inhibitor design and more widely within drug discovery are generally poorly understood. The successful targeting of these networks prospectively has great promise for all facets of inhibitor design, including potency and selectivity for the target. Herein, we describe the design and testing of a targeted library of 4-anilinoquin(az)olines for use as inhibitors of cyclin G-associated kinase (GAK). GAK cellular target engagement assays, ATP binding-site modelling and extensive water mapping provide a clear route to access potent inhibitors for GAK and beyond.     

Determinants of channel gating located in the N-terminal extracellular domain of nicotinic alpha7 receptor

We identified regions within the N-terminal extracellular domain of alpha7 nicotinic acetylcholine receptors that affect channel gating. By single-channel analysis of alpha7 nicotinic acetylcholine receptors currents, we show that the difference in efficacy between the two agonists acetylcholine and 1,1-dimethyl-4-phenylpiperazinium (DMPP) is due to a slower channel activation rate by DMPP. The partial efficacy of DMPP was not caused by channel block or faster desensitization of alpha7 AChRs by DMPP. In addition, the efficacy and, by inference, the activation rate were found to be voltage dependent. Using chimeras of the two closely related subunits alpha7 and alpha8, we map residues that affect channel activation rate and agonist affinity to two different regions of the extracellular domain. Residues that affect channel activation rate are within the sequence 1-179, whereas residues that affect agonist affinity are within the sequence 180-208.     

Development and validation of a thermal model of the direct chill casting of AZ31 magnesium billets

A mathematical model of the direct chill (DC) casting process for magnesium billets has been developed to predict the temperature in the billet, dummy block, and center pin using the commercial finite-element (FE) package, ABAQUS. Boundary conditions used for primary and secondary cooling and interfacial cooling between the billet and dummy block were defined based on the literature and knowledge of the physical phenomena occurring during the process. Temperatures in the billet, mold, and dummy block, as well as sump depth, were measured for a series of casting conditions during a plant trial conducted at Timminco Metals. The data obtained during the plant trial were used to “fine-tune” and validate the model for a variety of industrial casting conditions.