Modulation of bovine mononuclear cell proliferation during physiological transitions of the mammary gland

Mammary secretions and blood were collected from five primiparous Holstein cows 14 d following cessation of milking and 14 d prior to parturition for preparation of serum and mammary secretion skim fractions. Mammary secretions and blood were collected from the same animals 15 to 18 d following cessation of milking and 2 to 13 d prior to parturition for isolation of mononuclear cells. Effects of serum on mammary gland mononuclear cell proliferation and skim fractions from mammary secretions on blood mononuclear cell proliferation were evaluated. Mononuclear cell proliferation was evaluated in a mitogen-induced lymphocyte proliferation assay and in a mixed leukocyte assay. Proliferative responses of blood and mammary gland mononuclear cells did not vary significantly between the two time periods evaluated. Mammary secretion skim fractions obtained at both time periods significantly suppressed blood mononuclear cell proliferation. In contrast, exogenous serum enhanced mammary gland mononuclear cell proliferation in response to mitogens and allogeneic cells. Ability to enhance in vitro proliferation of mammary mononuclear cells isolated during physiological transitions of the mammary gland may suggest the potential for enhancing mammary mononuclear cell proliferation in vivo to reduce incidence of new intramammary infections at times when the mammary gland is highly susceptible.     

Experimental modification of attribution processes.

Attributional style is hypothesized to be a causative factor in depression vulnerability; however, no studies to date have examined whether manipulation of attributional style influences depressed mood. The purpose of this study was to determine whether computer-based cognitive bias modification (CBM) procedures could modify attributional style and influence stress vulnerability. Participants were provided with multiple training trials that were intended to promote the use of either a positive or a negative attributional style. Compared with individuals in the negative attributional style condition, individuals in the positive attributional style condition showed decreased tendency to make self-deficient causal attributions for poor performance on a difficult anagram test. Furthermore, individuals in the positive attributional style condition reported less depressed mood in response to this academic stressor. These results suggest that attributional style is not invariable and can potentially be modified with CBM approaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of night smoking, sleep disturbance, and their co-occurrence on smoking outcomes.

Recent evidence suggests that smoking during the night is an indicator of nicotine dependence and predicts smoking cessation failure. Night smokers are likely to experience disturbance to their sleep cycle when they wake to smoke, but we are not aware of the prevalence of night smokers' self-reported sleep disturbance. Because sleep disturbance also predicts smoking cessation failure, we examined how the pre-cessation risk factors of night smoking and sleep disturbance, and their co-occurrence, predict smoking cessation failure in a 6-week double-blind randomized controlled trial examining whether naltrexone augments the efficacy of the nicotine patch (O'Malley et al., 2006). Smokers (N = 385) completed the Pittsburgh Sleep Quality Index (Buysse, Reynolds, Monk, Berman, & Kupfer, 1989) and a single item of waking at night to smoke pre-cessation. Smoking status was determined at weeks 1, 6, 24, and 48 weeks after quitting. The two main findings were: (a) night smokers reported significantly greater sleep disturbance than nonnight smokers; and (b) smokers with co-occurring night smoking and sleep disturbance experienced significantly greater risk for smoking than smokers with neither risk factor. Results suggest that individuals who both wake during the night to smoke and report clinically-significant sleep disturbance represent a high-risk group of smokers. Future smoking cessation treatment might incorporate strategies related to managing these smokers' sleep habits and physiological dependence on nicotine in order to bolster their cessation outcomes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Highly-ordered supportless three-dimensional nanowire networks with tunable complexity and interwire connectivity for device integration

The fabrication of three-dimensional assemblies consisting of large quantities of nanowires is of great technological importance for various applications including (electro-)catalysis, sensitive sensing, and improvement of electronic devices. Because the spatial distribution of the nanostructured material can strongly influence the properties, architectural design is required in order to use assembled nanowires to their full potential. In addition, special effort has to be dedicated to the development of efficient methods that allow precise control over structural parameters of the nanoscale building blocks as a means of tuning their characteristics. This paper reports the direct synthesis of highly ordered large-area nanowire networks by a method based on hard templates using electrodeposition within nanochannels of ion track-etched polymer membranes. Control over the complexity of the networks and the dimensions of the integrated nanostructures are achieved by a modified template fabrication. The networks possess high surface area and excellent transport properties, turning them into a promising electrocatalyst material as demonstrated by cyclic voltammetry studies on platinum nanowire networks catalyzing methanol oxidation. Our method opens up a new general route for interconnecting nanowires to stable macroscopic network structures of very high integration level that allow easy handling of nanowires while maintaining their connectivity.     

The time resolution of the St Petersburg paradox

A resolution of the St Petersburg paradox is presented. In contrast to the standard resolution, utility is not required. Instead, the time-average performance of the lottery is computed. The final result can be phrased mathematically identically to Daniel Bernoulli's resolution, which uses logarithmic utility, but is derived using a conceptually different argument. The advantage of the time resolution is the elimination of arbitrary utility functions.     

Stretchable magnetoelectronics

We fabricated [Co/Cu] multilayers revealing a giant magnetoresistance (GMR) effect on free-standing elastic poly(dimethylsiloxane) (PDMS) membranes. The GMR performance of [Co/Cu] multilayers on rigid silicon and on free-standing PDMS is similar and does not change with tensile deformations up to 4.5%. Mechanical deformations imposed on the sensor are totally reversible, due to the elasticity of the PDMS membranes. This remarkable performance upon stretching relies on a wrinkling of GMR layers on top of the PDMS membrane.     

Effect of selection for growth rate on biochemical, quality and texture characteristics of meat from rabbits

Biochemical characteristics, including myosin heavy chain I (MHC-I) percentage, isocitrate dehydrogenase and aldolase activities, meat quality traits and instrumental texture properties of rabbits selected for different growth rates were studied. The animals of the control (C) group (7th generation; n=60) were raised in parallel with those of selection (S) group (21st generation; n=60). Carcass weights (1230.1 ± 19.8 and 1348.3 ± 20.1 g, for C and S, respectively) and perirenal and scapular fat content differed significantly (P<0.01) between the two groups. Water holding capacity was expressed as the percentage of pressure released water and was significantly different (P<0.05) between groups C and S (33.29% and 35.57%). MHC-I percentage and aldolase activity also differed significantly (P<0.05) between groups, group C showing higher oxidative traits than group S (MHC-I: 12.5% and 9.8%; aldolase: 597.11 and 636.83 UI/g muscle). Texture properties from the Warner-Bratzler test showed higher (P<0.001) shear firmness for loin in the S group (1.69 kg/s cm²) than in the C group (1.34 kg/s cm²). In addition, the texture profile analysis indicated that chewiness, gumminess and hardness were also higher in the S group (P<0.01). In conclusion, the results confirmed a positive effect of the selection on productive traits and a negative effect on instrumental texture properties and on the water holding capacity of the meat.     

Changes of glucosinolates in mixed fresh-cut broccoli and cauliflower florets in modified atmosphere packaging

ABSTRACT:  Glucosinolates of broccoli and cauliflower florets were assessed to determine the effect of modified-atmosphere packaging on postharvest glucosinolate dynamics in mixed florets of Brassica vegetables. Mixed-packaged broccoli and cauliflower florets stored in food trays sealed with 2 different microperforated biaxial-oriented polypropylene films for up to 7 d at 8 °C were analyzed. Both applied modified atmospheres (1% O₂+ 21% CO₂; 8% O₂+ 14% CO₂) maintained aliphatic glucosinolates in cauliflower florets, whereas in broccoli florets, the aliphatic glucosinolate concentration decreased slightly in each modified atmosphere. In addition, total indole glucosinolate concentration for both broccoli and cauliflower florets was maintained, and even increased in cauliflower florets at 1% O₂+ 21% CO₂ due to rising neoglucobrassicin concentration. Thus, to simultaneously maintain glucosinolates and external appearance as well as to prevent off-odor, a modified atmosphere of 1% O₂+ 21% CO₂ provides a suitable environment for storage of this Brassica floret medley for up to 7 d at 8°C.     

Simultaneous detection of mastitis pathogens, Staphylococcus aureus, Streptococcus uberis, and Streptococcus agalactiae by multiplex real-time polymerase chain reaction

The objective of this study was to develop a multiplex real-time polymerase chain reaction (PCR) method for simultaneous detection of Staphylococcus aureus, Streptococcus agalactiae, and Streptococcus uberis directly from milk. A genetic marker specific for Staph. aureus was used for primers and dual-labeled probe design. The target for Strep. agalactiae primers and dual-labeled probe was selected from the cfb gene encoding the Christie-Atkins-Munch-Petersen factor. The plasminogen activator gene was the target for primers and dual-labeled probe design for Strep. uberis. Quarter milk samples (n = 192) were analyzed by the multiplex real-time PCR assay and conventional microbiological methods. An additional 57 quarter milk samples were analyzed in a separate real-time PCR assay for Strep. agalactiae only. Using an overnight enrichment step, the real-time PCR technique correctly identified 96.4% of all quarter milk samples; 91.7% of Staph. aureus, 98.2% of Strep. agalactiae, and 100% of Strep. uberis. Results of conventional microbiological methods were used to determine the sensitivity and specificity of the multiplex real-time PCR procedure. The sensitivity of the procedure to correctly identify Staph. aureus, Strep. agalactiae, and Strep. uberis directly from milk was 95.5%, and the specificity was 99.6%. Results of this study indicate that the multiplex real-time PCR procedure has the potential to be a valuable diagnostic technique for simultaneous identification of Staph. aureus, Strep. agalactiae, and Strep. uberis directly from quarter milk samples.