Standardization of milk infrared spectra for the retroactive application of calibration models

The objective of this study was to standardize the infrared spectra obtained over time and across 2 milk laboratories of Canada to create a uniform historical database and allow (1) the retroactive application of calibration models for prediction of fine milk composition; and (2) the direct use of spectral information for the development of indicators of animal health and efficiency. Spectral variation across laboratories and over time was inspected by principal components analysis (PCA). Shifts in the PCA scores were detected over time, leading to the definition of different subsets of spectra having homogeneous infrared signal. To evaluate the possibility of using common equations on spectra collected by the 2 instruments and over time, we developed a standardization (STD) method. For each subset of data having homogeneous infrared signal, a total of 99 spectra corresponding to the percentiles of the distribution of the absorbance at each wavenumber were created and used to build the STD matrices. Equations predicting contents of saturated fatty acids, short-chain fatty acids, and C18:0 were created and applied on different subsets of spectra, before and after STD. After STD, bias and root mean squared error of prediction decreased by 66% and 32%, respectively. When calibration equations were applied to the historical nonstandardized database of spectra, shifts in the predictions could be observed over time for all investigated traits. Shifts in the distribution of the predictions over time corresponded to the shifts identified by the inspection of the PCA scores. After STD, shifts in the predicted fatty acid contents were greatly reduced. Standardization reduced spectral variability between instruments and over time, allowing the merging of milk spectra data from different instruments into a common database, the retroactive use of calibrations equations, or the direct use of the spectral data without restrictions.     

Book Reviews

This paper is part of a larger series, attempting to align Louis Kahn's ‘form and design’ theory with Platonism.¹ One obstacle to this alignment is the commonly held view that Kalm drew on historic precedents when conceiving his fundamental planning strategies, or die ‘form’ of his buildings, since Plato would have architects copy the Forms, or Ideas, directly. The opinions of the ‘source-hunters’ are reviewed, but found to contradict much of what Kahn said, as well as die opinions ofodier scholars and associates of Kahn's. The weight of the latter views casts doubt on those of die ‘source-hunters’, leaving open the possibility that Kahn drew on Forms directly, as Plato would have ‘craftsmen’ do.     

Changes in self-control problems and attention problems during middle school predict alcohol, tobacco, and marijuana use during high school.

Although deficits in impulse control have been linked to adolescent use of alcohol and illicit drugs, less attention has been given to variability in change in impulse control across adolescence and whether this variability may be a signal of risk for early substance use. The goals of the current study were to examine growth in two aspects of impulse control, self-control problems and attention problems, across middle adolescence, and to test the prospective effects of level and change in these variables on levels and change over time in substance use. Data are from a community sample of 955 adolescents interviewed (along with their parents and teachers) annually from 6th to 11th grade. Results indicated that greater self-control problems and attentional problems in the 6th grade and increases in these problems over time were associated with higher levels of substance use at 11th grade. Our results suggest that modeling change over time enhances the understanding of how impulse control influences the development of substance use. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Indian Hedgehog in Synovial Fluid Is a Novel Marker for Early Cartilage Lesions in Human Knee Joint

To determine whether there is a correlation between the concentration of Indian hedgehog (Ihh) in synovial fluid (SF) and the severity of cartilage damage in the human knee joints, the knee cartilages from patients were classified using the Outer-bridge scoring system and graded using the Modified Mankin score. Expression of Ihh in cartilage and SF samples were analyzed with immunohistochemistry (IHC), western blot, and enzyme-linked immunosorbent assay (ELISA). Furthermore, we detected and compared Ihh protein levels in rat and mice cartilages between normal control and surgery-induced osteoarthritis (OA) group by IHC and fluorescence molecular tomography in vivo respectively. Ihh expression was increased 5.2-fold in OA cartilage, 3.1-fold in relative normal OA cartilage, and 1.71-fold in OA SF compared to normal control samples. The concentrations of Ihh in cartilage and SF samples was significantly increased in early-stage OA samples when compared to normal samples (r = 0.556; p < 0.001); however, there were no significant differences between normal samples and late-stage OA samples. Up-regulation of Ihh protein was also an early event in the surgery-induced OA models. Increased Ihh is associated with the severity of OA cartilage damage. Elevated Ihh content in human knee joint synovial fluid correlates with early cartilage lesions.     

Time-Correlated Single Photon Counting With Microchannel Plate Detectors

ABSTRACT

We describe the experimental techniques and methods of analysis used in our laboratory in the study of a wide range of chemical and biological systems. In addition to standard single exponential decay time measurements we discuss the resolution of multiexponential decays and the analysis of fluorescence anisotropy experiments.     

Effect of phosphate binders on oxidative stress and inflammation markers in hemodialysis patients

It has been suggested that phosphate binders may reduce the inflammatory state of hemodialysis (HD) patients. However, it is not clear whether it has any effect on oxidative stress. The objective of this study was to evaluate the effect of sevelamer hydrochloride (SH) and calcium acetate (CA) on oxidative stress and inflammation markers in HD patients. Hemodialysis patients were randomly assigned to therapy with SH (n=17) or CA (n=14) for 1 year. Before the initiation of therapy (baseline) and at 12 months, we measured in vitro reactive oxygen species (ROS) production by stimulated and unstimulated polymorphonuclear neutrophils and serum levels of tumor necrosis factor α, interleukin-10, C-reactive protein, and albumin. There was a significant reduction of spontaneous ROS production in both groups after 12 months of therapy. There was a significant decrease of Staphylococcus aureus stimulated ROS production in the SH group. There was a significant increase in albumin serum levels only in the SH group. In the SH group, there was also a decrease in the serum levels of tumor necrosis factor α and C-reactive protein. Our results suggest that compared with CA treatment, SH may lead to a reduction in oxidative stress and inflammation. Therefore, it is possible that phosphate binders exert pleiotropic effects on oxidative stress and inflammation, which could contribute toward decreasing endothelial injury in patients in HD.     

Analysis of a Three-Phase Delta-Connected Inductive Load Controlled by an SCR-Diode Switch

A detailed analysis is presented of a system consisting of a three-phase delta-connected inductive static load controlled by a thyrode (SCR and diode) controller. The current equations are developed for a three-phase delta-connected inductive circuit representing the steady-state model of an induction motor. The simulated and actual current and voltage waveforms of an induction motor controlled by such an SCR-Diode controller are illustrated. The frequency/power spectra of the phase and line current are also presented.     

Bacterial contamination of cucumber fruit through adhesion

In this study, the adhesion of bacteria to fresh cucumber surfaces in aqueous suspension was shown to be dependent on time of incubation, inoculum species and concentration, and temperature. The adhesion of bacteria to the fruit in wash water was less extensive at lower temperatures and shorter exposure times. Various species of bacteria were adsorbed to cucumber surfaces in the following relative order: Salmonella Typhimurium > Staphylococcus aureus > Lactobacillus plantarum > Listeria monocytogenes. Cells were adsorbed at all temperatures tested (5, 15, 25, and 35 degrees C) at levels that depended on incubation time, but the numbers of cells adsorbed were larger at higher incubation temperatures. Levels of adhesion of bacteria to dewaxed fruit were higher for L. monocytogenes and lower for Salmonella Typhimurium, L. plantarum, and S. aureus than were levels of adhesion to waxed fruit.     

How can we learn to live with rivers? The findings of the Institution of Civil Engineers Presidential Commission on flood-risk management

In the wake of the floods of 1998 and 2000 the Government invited the Institution of Civil Engineers (ICE) to carry out a technical review of flood-risk management in England and Wales and to consider the most appropriate approaches to flood-risk management for the 21st century. The findings of this Commission are published in the ICE report Learning to live with rivers. Further information on the Commission and its work is available at www.icenet.org.uk/presidential.htm. This paper provides an introduction to the need for such a review and the scope of the Commission's work. A summary of the findings of the Commission are presented along with key recommendations for improved flood-risk management in the future.     

Timely Timelessness: Traditional Proportions and Modern Practice in Kahn’s Kimbell Museum

The twentieth century witnessed declining interest in architectural proportioning systems, which were virtually eclipsed by technical, social and fiscal agendas. Louis Kahn is a seminal architect, whose most acclaimed building, the Kimbell Art Museum (1966–72), represents a compelling case-study in the use proportions by twentieth-century architects. In spite of a raft of peculiarly modern restrictions (both technological and programmatic), Kahn appears – despite his espoused ambivalence concerning proportion – to have intentionally produced a building with an array of approximate geometrical as well as precise harmonic proportions. This two-part paper presents the findings of a multifaceted research project that examined the Kimbell’s proportions from numerous standpoints. Part 1 presents a textural analysis of Kahn’s statements regarding proportion, as well as the findings of an archival study of correspondence between the architect and his client and consultants. Part 2 presents a prima facie geometrical analysis of the construction drawings for the project. The division into parts reflects an apparent discrepancy between Kahn’s buildings and what he had to say about them.