1,235 research outputs found
Combined State and Parameter Estimation for a Static Model of the Maypole (Hoop-Column) Antenna Suface
Parameter and state estimation techniques are discussed for an elliptic system arising in a developmental model for the antenna surface of the Maypole Hoop/Column antenna. A computational algorithm based on spline approximations for the state and elastic parameters is given and numerical results obtained using this algorithm are summarized
Survey of Dairy Management Practices on One Hundred Thirteen North Central and Northeastern United States Dairies
The objective was to conduct a broad survey of dairy management practices that have an effect on animal well-being. Dairies were visited during the fall and winter of 2005 and 2006 in Wisconsin, Minnesota, Indiana, Iowa, and New York. Data were collected on 113 dairies on colostrum feeding, dehorning, tail-docking, euthanasia methods, producer statements about welfare, use of specialized calf-raising farms (custom), level of satisfaction with calf-raising by producers, and cow behavior. Calves were raised by the owner on 50.4% of dairies; 30.1% were raised on custom farms during the milk-feeding period, 18.6% were custom raised after weaning, and 1% sold calves with the option to buy them back as first-lactation heifers. A total of 51.8% of producers were very satisfied with their current calf-raising methods. Three feedings of colostrum were fed to the calves on 23.9% of dairies, 2 feedings on 39.8% of farms, 1 feeding on 31.0% of farms, and colostrum replacement products were fed on 5.3% of farms. Many farms (61.9%) provided 3.8 L at first feeding. Calves were dehorned at different ages by various methods. By 8 wk, 34.5% of calves were dehorned. By 12 wk, 78.8% of calves were dehorned. The majority of calves were dehorned by hot iron (67.3%). The remainder were dehorned by gouging (8.8%), paste (9.7%), saw (3.5%), or unknown by calf owner (10.6%). Anesthetic use was reported by 12.4% of dairy owners and analgesia use by 1.8%. Tail-docking was observed on 82.3% of dairies. The most common reported docking time was pre- or postcalving (35.2%). The second most commonly reported time was d 1 (15.4%). Rubber band was the most common method (92.5%), followed by amputation (7.5%). Three dairies amputated precalving, 1 at 2 mo and 3 at d 1 or 2. Cow hygiene was the most common reason given to dock (73.5%), followed by parlor worker comfort (17.4%) and udder health (1.0%). Producers reported 2.0% of cows obviously lame. Gun was the preferred euthanasia method (85.7%), followed by i.v. euthanasia (8.0%), live pick-up (1.8%), and nondisclosure (3.5%). Most producers (77.9%) stated that cows were in an improved environment as compared with 20 yr ago, whereas 8.0% stated conditions were worse, and 14.2% were undecided. Dairies with higher percentages of cows that either approached or touched the observer had lower somatic cell counts. The survey results showed management practices that were important for animal welfare
Effect of stall base type on herd health, costs, and producer satisfaction
The objective of this field study was to compare effect of stall base on herd health, stall maintenance, bedding cost, and producer satisfaction. Ninety-one dairies visited during a 4-mo period starting October 14, 2005 included 33 rubber-filled mattress (RFM), 27 sand, and 31 waterbed (WB) dairies. In this study, percent culled was higher for RFM (P = 0.001) and sand (P = 0.06) than WB stall base dairies. Percent of cows in fourth lactation or greater was higher on WB than either RFM (P = 0.01) or sand (P = 0.02) dairies. There was no difference between base types for production or somatic cell count. Bedding cost per bed per week was WB (0.89), and sand ($0.97). Sand beds were bedded less frequently (P = 0.01). Comparisons between RFM and sand indicate higher satisfaction for RFM regarding manure management (P \u3c 0.0001) and higher satisfaction with sand for cow comfort (P \u3c 0.0001). Producers with WB were more satisfied with base life (P \u3c 0.000 1) and cow comfort (P \u3c 0.000 1) than those with RFM. Producers with WB were more satisfied with cow longevity (P \u3c 0.0001) as compared to RFM. Length of sand stall was correlated with longevity (0.56, P = 0.01) while percent of mature cows was greater on dairies that provided WBs (P = 0.02). This data indicates that WB may be a viable option for cows and producers, when good quality sand is unavailable or handling sand-laden manure is not feasible
Watching others in a positive state does not induce optimism bias in common marmosets (Callithrix jacchus), but leads to behaviour indicative of competition
Emotional contagion is suggested to facilitate group life by enhancing synchronized responses to the environment. Cooperative breeders are an example of a social system that requires such intricate coordination between individuals. Therefore, we studied emotional contagion in common marmosets by means of a judgement bias test. Demonstrators were exposed to an emotion manipulation (i.e., positive, negative, control), and observers perceived only the demonstrator’s behaviour. We predicted that the positive or negative states of the demonstrator would induce matching states in the observer, indicating emotional contagion. All subjects’ emotional states were assessed through behaviour and cognition, the latter by means of a judgement bias test. Behavioural results showed a successful emotion manipulation of demonstrators, with manipulation-congruent expressions (i.e., positive calls in the positive condition, and negative calls and pilo-erect tail in the negative condition). Observers showed no manipulation-congruent expressions, but showed more scratching and arousal after the positive manipulation. Concerning the judgement bias test, we predicted that subjects in a positive state should increase their response to ambiguous cues (i.e., optimism bias), and subjects in a negative state should decrease their response (i.e., pessimism bias). This prediction was not supported as neither demonstrators nor observers showed such bias in either manipulation. Yet, demonstrators showed an increased response to the near-positive cue, and additional analyses showed unexpected responses to the reference cues, as well as a researcher identity effect. We discuss all results combined, including recently raised validation concerns of the judgement bias test, and inherent challenges to empirically studying emotional contagion
Influence of Free-Stall Base on Tarsal Joint Lesions and Hygiene in Dairy Cows
The objective was to quantify the incidence of tarsal lesions and level of hygiene by stall bed type. Cows were scored on 100 dairies from Wisconsin, Minnesota, Indiana, Iowa, and New York in the fall and winter. Thirty-eight dairies used rubber-filled mattresses (RFM), 27 had sand beds, 29 had waterbeds, and 6 used compost packs (CPk). Stocking density, stall dimensions, bedding amount, bedding frequency, and type of bedding were recorded. One pen of early-lactation multiparous cows on each dairy was scored based on injury of the tarsal joints at the lateral and medial surfaces and tuber calcis at the dorsal, lateral, and medial surfaces. A tarsal score of 1 represented hair loss, 2 was moderate, and 3 indicated severe swelling. Differences between bed types in the percentages of cows with lesions were tested with one-way ANOVA by lesion severity and incidence, with farm as the experimental unit. Cows on sand beds or waterbeds had fewer lesion scores of 1, 2, and 3 than those on RFM. The percentages of score 1 were 54.6 ± 4.4 (RFM), 22.5 ± 4.7 (sand), and 29.8 ± 4.3 (waterbed), whereas the percentages of score 2 were 14.0 ± 1.4, 2.3 ± 1.5, and 5.0 ± 1.4, and of score 3 were 3.0 ± 0.4, 0.2 ± 0.4, and 0.4 ± 0.4. Cows on CPk had no lesions. Hygiene scores ranged from 1 to 5, with 1 being clean and 5 soiled. The percentages of hygiene score 1 were 0 (compost), 0.4 (RFM), 0.4 (sand), and 0.4 (waterbeds); those with score 2 were 79.0, 84.0 ± 0.01, 73.2 ± 0.01, and 80.4 ± 0.01; with score 3 were 20.3, 15.2 ± 0.01, 23.8 ± 0.01, and 18.6 ± 0.01; with score 4 were 0.8, 0.005 ± 0.001, 0.006 ± 0.001, and 0.025 ± 0.003; and with score 5 was 0 for all bed types. Cows on RFM and waterbeds had improved hygiene compared with cows on sand beds. There was no difference in somatic cell count (SCC) by bed type. The percentage of cows in fourth lactation or greater on waterbeds (19.8 ± 1.8) was greater than those on RFM (13.3 ± 1.6) or on sand (13.5 ± 1.8). The percentage culled was lower for cows on waterbeds than on RFM (22.8 ± 1.5 vs. 29.4 ± 1.4). Score 3 tarsal lesions were correlated (r = 0.60) with SCC. The length of the sand bed was correlated with a greater percentage of mature cows. The SCC was correlated with the percentage of cows reported lame on the day of the visit (r = 0.45) and with neck rail height (r = −0.26). On dairies with RFM, severe lesions (r = 0.60), death losses (r = 0.52), and percentage of the herd reported lame on the day of the visit (r = 0.52) were all correlated with the SCC. Dairies with higher percentages of lesions had higher SCC, death losses, lameness, and culling rates. Adding bedding several times per week may reduce the incidence of lesions
Effect of stall base type on herd health, costs, and producer satisfaction
The objective of this field study was to compare effect of stall base on herd health, stall maintenance, bedding cost, and producer satisfaction. Ninety-one dairies visited during a 4-mo period starting October 14, 2005 included 33 rubber-filled mattress (RFM), 27 sand, and 31 waterbed (WB) dairies. In this study, percent culled was higher for RFM (P = 0.001) and sand (P = 0.06) than WB stall base dairies. Percent of cows in fourth lactation or greater was higher on WB than either RFM (P = 0.01) or sand (P = 0.02) dairies. There was no difference between base types for production or somatic cell count. Bedding cost per bed per week was WB (0.89), and sand ($0.97). Sand beds were bedded less frequently (P = 0.01). Comparisons between RFM and sand indicate higher satisfaction for RFM regarding manure management (P \u3c 0.0001) and higher satisfaction with sand for cow comfort (P \u3c 0.0001). Producers with WB were more satisfied with base life (P \u3c 0.000 1) and cow comfort (P \u3c 0.000 1) than those with RFM. Producers with WB were more satisfied with cow longevity (P \u3c 0.0001) as compared to RFM. Length of sand stall was correlated with longevity (0.56, P = 0.01) while percent of mature cows was greater on dairies that provided WBs (P = 0.02). This data indicates that WB may be a viable option for cows and producers, when good quality sand is unavailable or handling sand-laden manure is not feasible
A Police Officer’s Tacit Knowledge Inventory (POTKI): Establishing Construct Validity and Exploring Applications
Research summarizes the construction of a Police Officer’s Tacit Knowledge Inventory (Inventory), a situational judgment test comprised of knowledge gained on-the-job by experienced police officers, and examines if it can play a role in the development of expertise. Correlation and regression analysis was done to establish the Inventory’s ability to predict post-Academy graduation performance. Results show that Inventory response patterns correlate with Supervisor ratings; and the Inventory responses correctly predict significant differences between novice patrol officers and experienced police officers
Reactions of Phosphorylsulfenyl Chlorides with 2H-1,2,3-Diazaphospholes
Formation of a quasiphosphonium salt in reaction of phosphorylsulfenyl chlorides with 1,2,3-diazaphospholes was established by dynamic 31P NMR spectroscopy. The salt is formed by addition of 2 mol of phosphorylsulfenyl chloride to the σ2λ3P=C endocyclic fragment by the 1,1- and 1,2-addition schemes. Decomposition of the salt yields mainly O,O-dialkyl phosphothiochloridate and, to a lesser extent, dialkyl phosphochloridate
Fine Structure in the Circumstellar Environment of a Young, Solar-like Star: the Unique Eclipses of KH 15D
Results of an international campaign to photometrically monitor the unique
pre-main sequence eclipsing object KH 15D are reported. An updated ephemeris
for the eclipse is derived that incorporates a slightly revised period of 48.36
d. There is some evidence that the orbital period is actually twice that value,
with two eclipses occurring per cycle. The extraordinary depth (~3.5 mag) and
duration (~18 days) of the eclipse indicate that it is caused by circumstellar
matter, presumably the inner portion of a disk. The eclipse has continued to
lengthen with time and the central brightness reversals are not as extreme as
they once were. V-R and V-I colors indicate that the system is slightly bluer
near minimum light. Ingress and egress are remarkably well modeled by the
passage of a knife-edge across a limb-darkened star. Possible models for the
system are briefly discussed.Comment: 19 pages, 5 figure
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