Frequency domain laser velocimeter signal processor

A new scheme for processing signals from laser velocimeter systems is described. The technique utilizes the capabilities of advanced digital electronics to yield a signal processor capable of operating in the frequency domain maximizing the information obtainable from each signal burst. This allows a sophisticated approach to signal detection and processing, with a more accurate measurement of the chirp frequency resulting in an eight-fold increase in measurable signals over the present high-speed burst counter technology. Further, the required signal-to-noise ratio is reduced by a factor of 32, allowing measurements within boundary layers of wind tunnel models. Measurement accuracy is also increased up to a factor of five

A case of bovine raw milk contamination with Listeria monocytogenes

peer-reviewedDuring routine sampling of bulk raw milk on a dairy farm, the pathogenic bacteria Listeria monocytogenes was found to be a contaminant, at numbers < 100 cfu/ml. A strain with an indistinguishable pulsed-field gel electrophoresis pattern was isolated from the bulk milk two months later. Environmental swabs taken at the dairy environment were negative for the presence of L. monocytogenes, indicating a possible case of excretion of the L. monocytogenes directly into the milk. Milk samples were collected from the individual cows and analysed, resulting in the identification of L. monocytogenes excretion (at 280 cfu/ml) from one of the 4 mammary quarters of one dairy cow out of 180. When the infected cow was isolated from the herd, no L. monocytogenes was detected from the remaining herd. The pulsed-field gel electrophoresis pattern of the strain from the individual cow was indistinguishable from that originally isolated from the bulk milk. The infected cow did not show any clinical signs of disease, nor did the appearance of the milk have any physical abnormalities. Antibiotic treatment of the infected mammary quarter was found to be ineffective. This study shows that there can be risks associated with direct contamination of raw milk with L. monocytogenes.Teagasc Walsh Fellowship; Irish Department of Agriculture, Fisheries and Food, Food Institutional Research Measure (Irish Microbial Risk Assessment Network project); European Union (EU), 6th Framework Programme (BIOTRACER project)

Zincate-free, electroless nickel deposition on aluminum bond pads

A zincate-free electroless nickel deposition on aluminum bond pads is investigated. A three-step, etch, rinse, and electroless plating, is demonstrated for deposition on aluminum bond pads patterned with polyimide. The chemicals used are compatible with this dielectric material. The deposition has been achieved with good selectivity, uniformity, and deposition rate at 40 × 40   μ m aluminum bond pads. The adhesion and contact resistance were also determined and improved through anneals in the range 200-400°C for 1 h. The optimized condition for adhesion and contact resistance was an anneal at 400°C. The combination of a nickel hypophosphite reducing agent and the additives used leads to an active plating bath in the early stages of deposition, by comparison with commercial solutions, and hence, good coverage of the aluminum bond pad using the simplified process

Lying and Shirking Under Oath

This study explores whether an oath to honesty can reduce both shirking and lying among crowd-sourced internet workers. Using a classic coin-flip experiment, we first show that a substantial majority of Mechanical Turk workers both shirk and lie when reporting the number of heads flipped. We then demonstrate lying can be reduced by first asking each worker to swear voluntarily on his or her honor to tell the truth in subsequent economic decisions. The oath, however, did not reduce shirking as measured by time- at-coin-flip-task, although it did increase the time they spent answering a demographic survey. Conditional on response, MTurk shirkers and liars were less likely to agree to an ex post honesty oath. Our results suggest oaths may help elicit more truthful behavior in on-line crowd-sourced environments

Drip cooling of lactating sows

Twenty eight sows and gilts were used to evaluate the value of drip sprinkling to reduce heat stress in lactating sows. Respiration rates for sprinkled sows were significantly lower than those of controls. Daily feed intake was significantly higher for wetted sows versus the unwetted controls. No differences were observed between groups on number of pigs born alive, dead, number weaned or pig birth weight.; Swine Day, Manhattan, KS, November 10, 198

Tower tank valve flushing system for dairy facitlites

Flushing characteristics of a tower tank valve flushing system with a 12-inch-diameter manual valve were determined. Data were obtained using the outside cow alleys in a fourrow freestall barn. The alleys were 12 ft wide and 420 ft long with a 2% slope. The average flow rate exceeded 8,000 gallons per minute (gpm) when the average head was above 30 ft and the manual valve opened 80 degrees. Opening the valve to 90 degrees increased the flow rate to over 9,700 gpm. The velocity of the flushing wave was 8.5 fpm with a flow depth of 3.5 in. The estimated wave duration or alley contact time was 14.6 sec with a 25-40 sec release time from the flush tank. The flow rate ranged from 5,300 gpm to 7,200 gpm when the average head was between 16 and 28 ft.; Dairy Day, 1998, Kansas State University, Manhattan, KS, 1998

Carter-Payne homomorphisms and Jantzen filtrations

We prove a q-analogue of the Carter-Payne theorem in the case where the differences between the parts of the partitions are sufficiently large. We identify a layer of the Jantzen filtration which contains the image of these Carter-Payne homomorphisms and we show how these homomorphisms compose.Comment: 30 page

Multiple-locus variable number of tandem repeat analysis (MLVA) of Irish verocytotoxigenic Escherichia coli O157 from feedlot cattle: uncovering strain dissemination routes

<p>Abstract</p> <p>Background</p> <p>The identification of the routes of dissemination of <it>Escherichia coli (E. coli) </it>O157 through a cohort of cattle is a critical step to control this pathogen at farm level. The aim of this study was to identify potential routes of dissemination of <it>E. coli </it>O157 using Multiple-Locus Variable number of tandem repeat Analysis (MLVA).</p> <p>Results</p> <p>Thirty-eight environmental and sixteen cattle faecal isolates, which were detected in four adjacent pens over a four-month period were sub-typed. MLVA could separate these isolates into broadly defined clusters consisting of twelve MLVA types. Strain diversity was observed within pens, individual cattle and the environment.</p> <p>Conclusion</p> <p>Application of MLVA is a broadly useful and convenient tool when applied to uncover the dissemination of <it>E. coli </it>O157 in the environment and in supporting improved on-farm management of this important pathogen. These data identified diverse strain types based on amplification of VNTR markers in each case.</p

Tuning and controlling gene expression noise in synthetic gene networks

Synthetic gene networks can be used to control gene expression and cellular phenotypes in a variety of applications. In many instances, however, such networks can behave unreliably due to gene expression noise. Accordingly, there is a need to develop systematic means to tune gene expression noise, so that it can be suppressed in some cases and harnessed in others, e.g. in cellular differentiation to create population-wide heterogeneity. Here, we present a method for controlling noise in synthetic eukaryotic gene expression systems, utilizing reduction of noise levels by TATA box mutations and noise propagation in transcriptional cascades. Specifically, we introduce TATA box mutations into promoters driving TetR expression and show that these mutations can be used to effectively tune the noise of a target gene while decoupling it from the mean, with negligible effects on the dynamic range and basal expression. We apply mathematical and computational modeling to explain the experimentally observed effects of TATA box mutations. This work, which highlights some important aspects of noise propagation in gene regulatory cascades, has practical implications for implementing gene expression control in synthetic gene networks