Tailored interventions to communicate stage-matched information to smokers in different motivational stages.

Smokers in stages of low readiness to quit (immotives and precontemplators) and smokers in stages of high readiness to quit (contemplators and preparers) were randomly allocated to 1 of 4 tailored intervention conditions offering outcome information, self-efficacy-enhancing information, both sorts of information, or no information. Data on 1,540 smokers, stratified by stage, were analyzed. The primary outcome measure was stage transition. The hypotheses with regard to stage-matched information for immotives and precontemplators were not verified. With regard to contemplators and preparers, the following was found: Compared with the control group, contemplators benefited the most from both sorts of information, whereas preparers benefited the most from self-efficacy-enhancing information only. Comparisons between contemplators and preparers who were assigned to the matched treatment and contemplators and preparers who were assigned to the mismatched treatment supported these findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Applications drive secure lightpath creation across heterogeneous domains

We realize an open, programmable paradigm for application-driven network control by way of a novel network plane - the "service plane" - layered above legacy networks. The service plane bridges domains, establishes trust, and exposes control to credited users/applications while preventing unauthorized access and resource theft. The authentication, authorization, and accounting subsystem and the dynamic resource allocation controller are the two defining building blocks of our service plane. In concert, they act upon an interconnection request or a restoration request according to application requirements, security credentials, and domain-resident policy. We have experimented with such service plane in an optical, large-scale testbed featuring two hubs (NetherLight in Amsterdam, StarLight in Chicago) and attached network clouds, each representing an independent domain. The dynamic interconnection of the heterogeneous domains occurred at Layer 1. The interconnections ultimately resulted in an optical end-to-end path (lightpath) for use by the requesting grid application.     

Left ventricular hypertrophy; differences in the diagnostic and prognostic value of electrocardiography and echocardiography

OBJECTIVE: To compare the electrocardiogram (ECG) and the echocardiogram for demonstration of left ventricular hypertrophy (LVH) and the prognostic values of these methods. DESIGN: Literature study. SETTING: Department of General Practice, Social and Nursing Home Medicine, R.C. University of Nijmegen, the Netherlands. METHOD: Using articles retrieved by means of a search action in Medline (1962-January 1996), a study was made of the differences between determination of LVH by ECG and by echocardiography with regard to the sensitivities and specificities for measuring anatomical LVH, and their predictive values concerning cardiovascular morbidity and mortality. RESULTS: The sensitivity of echocardiography for the prediction of anatomical LVH (88-93%) exceeded that of ECG (21-54%), while both methods had a high specificity (77-97%). ECG-LVH seemed a better predictor of cardiovascular complications than echo-LVH. CONCLUSION: Echocardiography is the better instrument for screening for LVH, but ECG should keep its place in the diagnostics of LVH in view of its high predictive value for morbidity and mortality and its availability to primary health care. In regard to LVH, echocardiography measures only morphological disorders, while ECG also detects functional disorders.     

Hierarchical self-assembly of suspended branched colloidal nanocrystals into superlattice structures

Self-assembly of molecular units into complex and functional superstructures is ubiquitous in biology. The number of superstructures realized by self-assembly of man-made nanoscale units is also growing. However, assemblies of colloidal inorganic nanocrystals are still at an elementary level, not only because of the simplicity of the shape of the nanocrystal building blocks and their interactions, but also because of the poor control over these parameters in the fabrication of more elaborate nanocrystals. Here, we show how monodisperse colloidal octapod-shaped nanocrystals self-assemble, in a suitable solution environment, on two sequential levels. First, linear chains of interlocked octapods are formed, and subsequently the chains spontaneously self-assemble into three-dimensional superstructures. Remarkably, all the instructions for the hierarchical self-assembly are encoded in the octapod shape. The mechanical strength of these superstructures is improved by welding the constituent nanocrystals together.     

Dietary energy source in dairy cows in early lactation: metabolites and metabolic hormones

Negative energy balance-related metabolic disorders suggest that the balance between available lipogenic and glucogenic nutrients is important. The objectives of this study were to compare the effects of a glucogenic or a lipogenic diet on liver triacylglycerides (TAG), metabolites, and metabolic hormones in dairy cows in early lactation and to relate metabolite concentrations to the determined energy retention in body mass (ER). Sixteen dairy cows were fed either a lipogenic or glucogenic diet from wk 3 prepartum to wk 9 postpartum (pp) and were housed in climate respiration chambers from wk 2 to 9 pp. Diets were isocaloric (net energy basis). Postpartum, cows fed a lipogenic diet tended to have higher nonesterified fatty acid concentration (NEFA; 0.46 ± 0.04 vs. 0.37 ± 0.04 mmol/L) and lower insulin concentration (4.0 ± 0.5 vs. 5.5 ± 0.6 μIU/mL). No difference was found in plasma glucose, β-hydroxybutyrate, insulin-like growth factor-I, and thyroid hormones. Liver TAG was equal between both diets in wk −2 and 2 pp. In wk 4 pp cows fed the glucogenic diet had numerically lower TAG levels, although there was no significant dietary effect. Negative relationships were detected between ER and milk fat and between ER and NEFA. A positive relationship was detected between ER and insulin concentration. Overall, results suggest that insulin plays a regulating role in altering energy partitioning between milk and body tissue. Feeding lactating dairy cows a glucogenic diet decreased mobilization of body fat compared with a lipogenic diet. The relative abundance of lipogenic nutrients, when feeding a more lipogenic diet, is related to more secretion of lipogenic nutrients in milk, lower plasma insulin, and higher plasma NEFA concentration.     

Dietary inclusion of diallyl disulfide, yucca powder, calcium fumarate, an extruded linseed product, or medium-chain fatty acids does not affect methane production in lactating dairy cows

Two similar experiments were conducted to assess the effect of diallyl disulfide (DADS), yucca powder (YP), calcium fumarate (CAFU), an extruded linseed product (UNSAT), or a mixture of capric and caprylic acid (MCFA) on methane production, energy balance, and dairy cow performance. In experiment 1, a control diet (CON1) and diets supplemented with 56 mg of DADS/kg of dry matter (DM), 3 g of YP/kg of DM, or 25 g of CAFU/kg of DM were evaluated. In experiment 2, an inert saturated fat source in the control diet (CON2) was exchanged isolipidically for an extruded linseed source (100 g/kg of DM; UNSAT) or a mixture of C8:0 and C10:0 (MCFA; 20.3 g/kg of DM). In experiment 2, a higher inclusion level of DADS (200 mg/kg of DM) was also tested. Both experiments were conducted using 40 lactating Holstein-Friesian dairy cows. Cows were adapted to the diet for 12 d and were subsequently kept in respiration chambers for 5 d to evaluate methane production, diet digestibility, energy balance, and animal performance. Feed intake was restricted to avoid confounding effects of possible differences in ad libitum feed intake on methane production. Feed intake was, on average, 17.5 and 16.6 kg of DM/d in experiments 1 and 2, respectively. None of the additives reduced methane production in vivo. Methane production in experiment 1 was 450, 453, 446, and 423 g/d for CON1 and the diets supplemented with DADS, YP, and CAFU, respectively. In experiment 2, methane production was 371, 394, 388, and 386 g/d for CON2 and the diets supplemented with UNSAT, MCFA, and DADS, respectively. No effects of the additives on energy balance or neutral detergent fiber digestibility were observed. The addition of MCFA increased milk fat content (5.38% vs. 4.82% for control) and fat digestibility (78.5% vs. 59.8% for control), but did not affect milk yield or other milk components. The other products did not affect milk yield or composition. Results from these experiments emphasize the need to confirm methane reductions observed in vitro with in vivo data.     

Technical note: Evaluation of an ear-attached movement sensor to record cow feeding behavior and activity

The ability to monitor dairy cow feeding behavior and activity could improve dairy herd management. A 3-dimensional accelerometer (SensOor; Agis Automatisering BV, Harmelen, the Netherlands) has been developed that can be attached to ear identification tags. Based on the principle that behavior can be identified by ear movements, a proprietary model classifies sensor data as “ruminating,” “eating,” “resting,” or “active.” The objective of the study was to evaluate this sensor on accuracy and precision. First, a pilot evaluation of agreement between 2 independent observers, recording behavior from 3 cows for a period of approximately 9 h each, was performed. Second, to evaluate the sensor, the behavior of 15 cows was monitored both visually (VIS) and with the sensor (SENS), with approximately 20 h of registration per cow, evenly distributed over a 24-h period, excluding milking. Cows were chosen from groups of animals in different lactation stages and parities. Each minute of SENS and VIS data was classified into 1 of 9 categories (8 behaviors and 1 transition behavior) and summarized into 4 behavioral groups, namely ruminating, eating, resting, or active, which were analyzed by calculating kappa (κ) values. For the pilot evaluation, a high level of agreement between observers was obtained, with κ values of ≥0.96 for all behavioral categories, indicating that visual observation provides a good standard. For the second trial, relationships between SENS and VIS were studied by κ values on a minute basis and Pearson correlation and concordance correlation coefficient analysis on behavior expressed as percentage of total registration time. Times spent ruminating, eating, resting, and active were 42.6, 15.9, 31.6, and 9.9% (SENS) respectively, and 42.1, 13.0, 30.0, and 14.9% (VIS), respectively. Overall κ for the comparison of SENS and VIS was substantial (0.78), with κ values of 0.85, 0.77, 0.86, and 0.47 for “ruminating,” “eating,” “resting,” and “active,” respectively. Pearson correlation and concordance correlation coefficients between SENS and VIS for “ruminating,” “eating,” “resting,” and “active” were 0.93, 0.88, 0.98, and 0.73, and 0.93, 0.75, 0.97, and 0.35, respectively. In conclusion, the results provide strong evidence that the present ear sensor technology can be used to monitor ruminating and resting behavior of freestall-housed dairy cattle. Our results also suggest that this technology shows promise for monitoring eating behavior, whereas more work is needed to determine its suitability to monitor activity of dairy cattle.     

Bacterial flora associated with udder cleft dermatitis in Dutch dairy cows

Udder cleft dermatitis (UCD) or udder sores is a skin lesion, characteristically located around the anterior junction between the udder and abdomen of dairy cows. It is a worldwide problem in dairy herds with a large effect on animal welfare. The etiology and possible infectious origins of UCD are largely unknown; however, specific bacterial or parasitic causes are suggested in the literature. Therefore the aim of this study was to investigate the possible bacteriological, mycological, or parasitic involvement in clinically scored UCD lesions. Bacteriological culture was performed on subcutaneous tissue samples taken postmortem at a depth of 5 to 10 mm of 87 mild or severe UCD lesions or from the same place in healthy cows. Fungal culture was performed on a subset of 22 subcutaneous tissue samples of severe UCD postmortem. To investigate the superficial flora, swabs were taken from normal skin or skin lesions of 15 live animals equally divided over 3 groups: healthy skin or mild and severe UCD lesions. Histopathology, to describe and classify the lesions and to assess the presence of mites, fungi, or bacteria, was performed on 128 tissue samples, taken separately. In severe UCD lesions, Trueperella pyogenes and Bacteroides pyogenes were more frequently present in deep tissue layers and in superficial layers, compared with the same layers in mild UCD lesions or healthy skin. Culturing and histopathology indicated no sign of involvement of treponemes, Staphylococcus aureus, Escherichia coli, fungi, or mites in the UCD lesions. Histopathological examination showed that the majority of the lesions were characterized by chronic aspecific inflammation. Severe UCD lesions more frequently showed chronic active inflammation on histopathology, compared with mild UCD lesions. Due to the cross-sectional character of this study, it is difficult to differentiate cause and effect; however, future preventive and curative measures against UCD should take into account the chronic and anaerobic nature of this illness.     

A Bayesian approach to analyze energy balance data from lactating dairy cows

The objective of the present investigation was to develop a Bayesian framework for updating and integrating covariate information into key parameters of metabolizable energy (ME) systems for dairy cows. The study addressed specifically the effects of genetic improvements and feed quality on key parameters in current ME systems. These are net and metabolizable energy for maintenance (NE_M and ME_M, respectively), efficiency of utilization of ME for milk production (k_L) and growth (k_G), and efficiency of utilization of body stores for milk production (k_T). Data were collated from 38 studies, yielding 701 individual cow observations on milk energy, ME intake, and tissue gain and loss. A function based on a linear relationship between milk energy and ME intake and correcting for tissue energy loss or gain served as the basis of a full Bayesian hierarchical model. The within-study variability was modeled by a Student t-distribution and the between-study variability in the structural parameters was modeled by a multivariate normal distribution. A meaningful relationship between genetic improvements in milk production and the key parameters could not be established. The parameter k_L was linearly related to feed metabolizability, and the slope predicted a 0.010 (−0.0004; 0.0210) change per 0.1-unit change in metabolizability. The effect of metabolizability on k_L was smaller than assumed in present feed evaluation systems and its significance was dependent on collection of studies included in the analysis. Three sets of population estimates (with 95% credible interval in parentheses) were generated, reflecting different degrees of prior belief: (1) Noninformative priors yielded 0.28 (0.23; 0.33) MJ/(kg^0.75d), 0.55 (0.51; 0.58), 0.86 (0.81; 0.93) and 0.66 (0.58; 0.75), for NE_M, k_L, k_G, and k_T, respectively; (2) Introducing an informative prior that was derived from a fasting metabolism study served to combine the most recent information on energy metabolism in modern dairy cows. The new estimates of NE_M, k_L, k_G and k_T were 0.34 (0.28; 0.39) MJ/(kg^0.75d), 0.58 (0.54; 0.62), 0.89 (0.85; 0.95), and 0.69 (0.60; 0.79), respectively; (3) finally, all informative priors were used that were established from literature, yielding estimates for NE_M, k_L, k_G, and k_T of 0.29 (0.11; 0.46) MJ/(kg^0.75d), 0.60 (0.54; 0.70), 0.70 (0.50; 0.88), and 0.80 (0.67; 0.97), respectively. Bayesian methods are especially applicable in meta-analytical studies as information can enter at various stages in the hierarchical model.     

Abomasal infusion of ground corn and ammonium chloride in early-lactating Holstein-Friesian dairy cows to induce hindgut and metabolic acidosis

Next to rumen acidosis, other forms of acidosis may also affect lactational performance of cows. Therefore, the effects of hindgut acidosis, induced via abomasal infusion of ground corn, and metabolic acidosis, induced via abomasal infusion of NH₄Cl, were studied in cows in early lactation. Observations were made on intake and digestibility of nutrients, lactation performance, energy and N partitioning, blood acid-base status, and rumen and hindgut fermentation characteristics. In a 6 × 6 Latin square design, 6 rumen-fistulated, second-lactation Holstein-Friesian dairy cows (48 ± 17 d in milk) were subjected to 5 d of continuous abomasal infusions of water as control, or solutions of 2.5 mol of NH₄Cl/d, 5.0 mol of NH₄Cl/d, 3.0 kg of ground corn/d, or the combination of ground corn with either of the 2 NH₄Cl levels, followed by 2 d of rest. Treatment solutions were administered via peristaltic pumps through infusion lines attached to the rumen cannula plug and an abomasal infusion line with a flexible disk (equipped with holes to allow digesta passage) to secure its placement through the sulcus omasi. A total mixed ration consisting of 70% grass silage and 30% concentrate (on dry matter basis) was fed at 95% of ad libitum intake of individual cows. The experiment was conducted in climate respiration chambers to determine feed intake, lactation performance, and energy and N balance. Abomasal infusion of NH₄Cl affected the acid-base status of the cows, but more strongly when in combination with abomasal infusion of ground corn. Metabolic acidosis (defined as a blood pH < 7.40, blood HCO₃ concentration < 25.0 mmol/L, and a negative base excess) was observed with 5.0 mol of NH₄Cl/d, 3.0 kg of ground corn/d + 2.5 mol of NH₄Cl/d, and 3.0 kg of ground corn/d + 5.0 mol of NH₄Cl/d. Metabolic acidosis was associated with decreased milk lactose content, metabolic body weight, energy retained as protein, and fecal N excretion, and increased urine N excretion, and tended to decrease intake of nutrients. Digestibility of several nutrients increased with 5.0 mol of NH₄Cl/d, likely as a result of decreased intake. Abomasal ground corn infusion resulted in hindgut acidosis, where fecal pH decreased from 6.86 without ground corn to 6.00 with ground corn, regardless of NH₄Cl level. The decrease in fecal pH was likely the result of increased hindgut fermentation, evidenced by increased fecal volatile fatty acid concentrations. Hindgut acidosis was associated with decreased digestibility of nutrients, except for starch, which increased, and crude fat, which was not affected. No systemic inflammatory response was observed, suggesting that the hindgut epithelium was not severely affected by the more acidic conditions or barrier damage. Abomasal infusion of ground corn increased milk yield, milk protein and lactose yield, fecal N excretion, N use efficiency, and total energy retained as well as energy retained in fat, and reduced milk fat content and urine N excretion.