Influence of ethanol on the rennet-induced coagulation of milk

The influence of ethanol on the rennet-induced coagulation of milk was studied to investigate potential synergistic effects of these two mechanisms of destabilisation on the casein micelles. Addition of 5% (v/v) ethanol reduced the rennet coagulation time (RCT) of milk, whereas higher levels of ethanol (10-20%, v/v) progressively increased RCT. The temperature at which milk was coagulable by rennet decreased with increasing ethanol content of the milk. The primary stage of rennet coagulation, i.e., the enzymatic hydrolysis of kappa-casein, was progressively slowed with increasing ethanol content (5-20%, v/v), possibly due to ethanol-induced conformational changes in the enzyme molecule. The secondary stage of rennet coagulation, i.e., the aggregation of kappa-casein-depleted micelles, was enhanced in the presence of 5-15% ethanol, the effect being largest at 5% ethanol. Enhanced aggregation of micelles is probably due to an ethanol-induced decrease in inter-micellar steric repulsion. These results indicate an interrelationship between the effects of ethanol and chymosin on the casein micelles in milk, which may have interesting implications for properties of dairy products.     

Information sharing in capacity constrained supply chains under lost sales

We present a modelling approach for quantifying the value of information in supply chains using Markov decision processes (MDP). The case where information sharing occurs is modelled using a completely observable MDP. A restricted observation MDP is used to model the case where no information sharing occurs. We illustrate the use of this framework on a two-stage capacity-constrained supply chain consisting of a supplier and a retailer. We quantify the value of information sharing in this setting and construct several performance measures to identify the benefits to both the retailer and supplier as a result of the information sharing partnership.     

Development of a beef flavor lexicon and its application to compare the flavor profile and consumer acceptance of rib steaks from grass- or grain-fed cattle

Ten panelists were selected from the local community to develop a meat lexicon composed of 18 terms that describe flavor attributes found in red meats. This flavor lexicon was used to compare the flavor profile of meat from beef cattle finished on grass or grain. Steaks from grass-fed animals were significantly (P < 0.05) higher in barny, bitter, gamey, and grassy flavor, and lower in juicy and umami notes. Gamey, barny, bitter and grassy were some of the attributes inversely correlated to the degree of liking of the meat and therefore can be classified as “negative” attributes. Brothy, umami, roast beef, juicy, browned, fatty and salty are some of the attributes positively correlated to the degree of liking of beef and therefore can be identified as attributes that drive consumers’ acceptance. Steaks from grass-fed cattle were rated by consumers as slightly liked (6.08 on a 9-point scale), while steaks from grain-fed animals were rated as moderately liked (7.05 on a 9-point scale).     

High pressure-induced denaturation of alpha-lactalbumin and beta-lactoglobulin in bovine milk and whey: a possible mechanism

In this study, high pressure (HP)-induced denaturation of alpha-lactalbumin (alpha-la) and beta-lactoglobulin (beta-lg) in dairy systems was examined. In both milk and whey, beta-lg was less baroresistant than alpha-la; both proteins were considerably more resistant to HP-induced denaturation in whey than in milk. HP-induced denaturation of alpha-la and beta-lg increased with increasing proportion of milk in mixtures of milk and whey. Addition of a sulphydryl-oxidising agent, KlO3, to milk or whey increased HP-induced denaturation of beta-lg, but reduced the denaturation of alpha-la. Denaturation of both alpha-la and beta-lg was prevented by adding a sulphydryl-blocking agent, N-ethylmaleimide, to milk or whey prior to HP treatment, highlighting the crucial role of sulphydryl-disulphide interchange reactions in HP-induced denaturation of alpha-la and beta-lg. Removal of colloidal calcium phosphate from milk also reduced HP-induced denaturation of alpha-la and beta-lg significantly. The higher level of HP-induced denaturation of alpha-la and beta-lg in milk than in whey may be the result of the abscence of the casein micelles and colloidal calcium phosphate from whey, which facilitate HP-induced denaturation of alpha-la and beta-lg in milk.     

Towards a model-based integration of co-registered electroencephalography/functional magnetic resonance imaging data with realistic neural population meshes

Brain activity can be measured with several non-invasive neuroimaging modalities, but each modality has inherent limitations with respect to resolution, contrast and interpretability. It is hoped that multimodal integration will address these limitations by using the complementary features of already available data. However, purely statistical integration can prove problematic owing to the disparate signal sources. As an alternative, we propose here an advanced neural population model implemented on an anatomically sound cortical mesh with freely adjustable connectivity, which features proper signal expression through a realistic head model for the electroencephalogram (EEG), as well as a haemodynamic model for functional magnetic resonance imaging based on blood oxygen level dependent contrast (fMRI BOLD). It hence allows simultaneous and realistic predictions of EEG and fMRI BOLD from the same underlying model of neural activity. As proof of principle, we investigate here the influence on simulated brain activity of strengthening visual connectivity. In the future we plan to fit multimodal data with this neural population model. This promises novel, model-based insights into the brain's activity in sleep, rest and task conditions.     

Technical developments at the KIT gyrotron test facility

Parasitic beam tunnel oscillations have been discovered on some of the series production gyrotrons for W7-X and also on the coaxial pre-prototype gyrotron for ITER. Solutions to remedy these problems have resulted in a modified beam tunnel design, technologically close to the existing beam tunnel. The new design has successfully been tested on both the coaxial and also the f-step-tunable gyrotrons and has subsequently been implemented on one of the W7-X series-production-tubes presently undergoing factory acceptance tests in Karlsruhe.The ECRH test loads at KIT are operated under normal atmospheric conditions. Several loads have eventually failed in 1 MW long pulse experiments and KIT has therefore started to design its own loads. The first KIT-load is based on a fixed conical mirror and an aluminum cylinder coated with a lossy material for increased absorption. The new load has so far successfully been used during the acceptance tests of two 1-MW CW gyrotrons. Nevertheless a new load based on pure (uncoated) stainless steel absorbers is being developed as a backup solution for the ongoing high priority gyrotron testing.A superconducting magnet capable of rapid field changes between 4.15 and 5.67 T for frequency step-tunable gyrotrons has been procured, has demonstrated a (static) field of 7.2 T and its capability of rapid field-changes.     

A variant human IgG1-Fc mediates improved ADCC

Ribosome display was applied to the Fc region of human immunoglobulin G (IgG1) to select for improved binding to human FcγRIIIa, the receptor expressed on human natural killer cells that mediates antibody-dependent cellular cytotoxicity (ADCC). A library of human Fcγ1 variants was generated using error-prone polymerase chain reaction, and subjected to multiple rounds of ribosome display selection against progressively decreasing concentrations of soluble human FcγRIIIa, to enrich for improved binders. Radioimmunoassay and alphascreen analyses of the aglycosylated IgG-Fc output revealed variants with improved binding to FcγRIIIa relative to wild-type IgG-Fc. Subsequent expression in human (HEK-EBNA) cells generated glycosylated IgGs with modified activity in ADCC assays. One particular variant, 125_B01 triggered enhanced ADCC (EC(50) up to four-fold reduced with increased maximal lysis) relative to wild-type antibody, having more equal levels of ADCC for each allotype (V158/F158) of FcγRIIIa. Deconvolution of individual replacements within the variant showed that improved function arose from the Phe243Leu replacement within the CH2 domain, rather than the CH3 domain replacements Thr393Ala or His433Pro. Surprisingly, the oligosaccharide profiles of 125_B01 indicated more oligosaccharide chains lacking fucose, or with bisecting N-acetylglucosamine relative to wild-type IgG1, which correlates with improved function and the replacement Phe243Leu that is a carbohydrate contact residue within the C(H)2 domain.     

Dry-or-buy decision support for dry kiln scheduling in furniture production

In this paper, a dry-or-buy cost model for a dry kiln scheduling problem in the furniture manufacturing industry is considered. Factory-specified due-dates for jobs, kiln availability, kiln capacity, and drying and buying costs are incorporated into an Integer-Programming (IP) model. As it may be difficult (i.e., because of due-dates, kiln availability, processing times, etc.) to meet all the due-dates, certain jobs may have to be out-sourced. The objective of the model is to minimize the total drying and buying costs while satisfying all due-dates. Because of the computational complexity of the problem, a heuristic approach is developed. Computational experience indicates that the heuristic gives high quality solutions with significant savings in time over standard IP algorithms.     

Ambulatory cardiovascular activity in Vietnam combat veterans with and without posttraumatic stress disorder.

The present study investigated the relationship between daily diary affect ratings and ambulatory cardiovascular activity in 117 male Vietnam combat veterans (61 with posttraumatic stress disorder [PTSD] and 56 without PTSD). Participants completed 12–14 hr of ambulatory monitoring and daily diary affect ratings. Compared with veterans without PTSD, veterans with PTSD reported higher negative affect and lower positive affect in daily diary ratings. No differences were detected for mean laboratory initial recordings or mean ambulatory heart rate (HR), systolic blood pressure (SBP), or diastolic blood pressure (DBP). However, compared with veterans without PTSD, veterans with PTSD demonstrated higher SBP and DBP variability and a higher proportion of HR activity (compared with initial recording values) during daily activity. There was a significant Time of Day × Group interaction for mean HR, with a trend for PTSD participants to maintain HR levels during evening hours. (PsycINFO Database Record (c) 2010 APA, all rights reserved)