Energy Loss from a Moving Vortex in Superfluid Helium

We present measurements on both energy loss and pinning for a vortex terminating on the curved surface of a cylindrical container. We vary surface roughness, cell diameter, fluid velocity, and temperature. Although energy loss and pinning both arise from interactions between the vortex and the surface, their dependences on the experimental parameters differ, suggesting that different mechanisms govern the two effects. We propose that the energy loss stems from reconnections with a mesh of microscopic vortices that covers the cell wall, while pinning is dominated by other influences such as the local fluid velocity.Comment: 8 pages, 6 figure

DATA MINING: A SEGMENTATION ANALYSIS OF U.S. GROCERY SHOPPERS

Consumers make choices about where to shop based on their preferences for a shopping environment and experience as well as the selection of products at a particular store. This study illustrates how retail firms and marketing analysts can utilize data mining techniques to better understand customer profiles and behavior. Among the key areas where data mining can produce new knowledge is the segmentation of customer data bases according to demographics, buying patterns, geographics, attitudes, and other variables. This paper builds profiles of grocery shoppers based on their preferences for 33 retail grocery store characteristics. The data are from a representative, nationwide sample of 900 supermarket shoppers collected in 1999. Six customer profiles are found to exist, including (1) "Time Pressed Meat Eaters", (2) "Back to Nature Shoppers", (3) "Discriminating Leisure Shoppers", (4) "No Nonsense Shoppers", (5) "The One Stop Socialites", and (6) "Middle of the Road Shoppers". Each of the customer profiles is described with respect to the underlying demographics and income. Consumer shopping segments cut across most demographic groups but are somewhat correlated with income. Hierarchical lists of preferences reveal that low price is not among the top five most important store characteristics. Experience and preferences for internet shopping shows that of the 44% who have access to the internet, only 3% had used it to order food.Consumer/Household Economics, Food Consumption/Nutrition/Food Safety,

THE SUPERMARKET INDUSTRY AT THE START OF THE 21st CENTURY: KEY FINDINGS FROM THE 2000 SUPERMARKET PANEL

The 2000 Supermarket Panel gathered data on store characteristics, management practices, and operating performance from a representative, nation-wide sample of supermarkets. The Panel is unique because the unit of analysis is the individual store, and the same stores will be surveyed over time. Linking information on management practices and store and market characteristics with measures for key performance measures provides useful information for both strategic and tactical decisions. Descriptive findings are presented for stores groups by ownership group size and format. Results from a multivariate analysis of relationships between store performance and key performance drivers also are presented.Agribusiness,

Dynamics of perpendicular recording heads

3D modeling and inductance measurements were used to design an ultra-high frequency perpendicular system. Kerr microscopy and spin-stand experiments with focused ion beam (FI-B) trimmed perpendicular heads and perpendicular media directly verified the high frequency concepts

Counterfactual fairness for small subgroups

While methods for measuring and correcting differential performance in risk prediction models have proliferated in recent years, most existing techniques can only be used to assess fairness across relatively large subgroups. The purpose of algorithmic fairness efforts is often to redress discrimination against groups that are both marginalized and small, so this sample size limitation often prevents existing techniques from accomplishing their main aim. We take a three-pronged approach to address the problem of quantifying fairness with small subgroups. First, we propose new estimands built on the "counterfactual fairness" framework that leverage information across groups. Second, we estimate these quantities using a larger volume of data than existing techniques. Finally, we propose a novel data borrowing approach to incorporate "external data" that lacks outcomes and predictions but contains covariate and group membership information. This less stringent requirement on the external data allows for more possibilities for external data sources. We demonstrate practical application of our estimators to a risk prediction model used by a major Midwestern health system during the COVID-19 pandemic

Sonography of extraaxial fluid in neurologically normal infants with head circumference greater than or equal to the 95th percentile for age.

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135166/1/jum2000197443.pd

The Lockheed OSO-8 program. Analysis of data from the mapping X-ray heliometer experiment

The final report describes the extent of the analysis effort, and other activities associated with the preservation and documentation of the data set are described. The main scientific results, which are related to the behavior of individual solar activity regions in the energy band 1.5 - 15 keV, are summarized, and a complete bibliography of publications and presentations is given. Copies of key articles are also provided

Amino acid losses during hemodialysis with infusion of amino acids and glucose

Amino acid losses during hemodialysis with infusion of amino acids and glucose. This study evaluated the effects during hemodialysis of intravenous infusion of amino acids and glucose on plasma amino acid and glucose concentrations and amino acid losses. Eight men undergoing maintenance hemodialysis were each studied during two dialyses using glucose-free dialysate. During one hemodialysis, they were infused with 800ml of normal saline. During the other hemodialysis, they were infused with an equal volume of water which contained 39.5g of essential and non-essential free L-amino acids and 200g of d-glucose. The solutions were infused throughout the dialysis procedure into the drip chamber of the venous outflow from the dialyzer. Subjects were fasted from the night before until the end of hemodialysis, and the order of administration of the two solutions was determined randomly. Plasma essential, non-essential, and total amino acids fell significantly during the infusion of normal saline and rose during the administration of amino acids and glucose. Dialysate total-free amino acid losses averaged 8.2 ± 3.1SDg during the infusion of normal saline and 12.6 ± 3.6g with the administration of amino acids and glucose. These findings indicate that the intravenous infusion of amino acids and glucose during hemodialysis prevents a fall in plasma amino acid and glucose concentrations and leads to only a slight increase in the losses of free amino acids into dialysate. Because most of the infused amino acids are retained, this technique may be used during hemodialysis to avoid a net outflow of amino acids, minimize disruption of amino acid and glucose pools, and provide a nutritional supplement.Pertes en amino-acides au cours de l'hémodialyse avec perfusion d'acides aminés et de glucose. Cette étude a permis d'évaluer les effets de la perfusion intraveineuse d'acides aminés et de glucose pendant l'hémodialyse sur les concentrations plasmatiques d'acides aminés et de glucose, et les pertes d'acides aminés. Huit hommes en hémodialyse chronique ont chacun été étudiés pendant deux dialyses avec un dialysat sans glucose. Pendant une des dialyses ils étaient perfusés avec 800ml de soluté physiologique. Pendant l'hemodialyse autre ils ont infusé avec un égal volume d'eau contenant 39,5g de L-acides aminés libres essentiels ou non, et 200g de d-glucose. Les solutions étaient perfusées pendant la dialyse dans la tubulure veineuse venant du dialyseur. Les malades étaient à jeûn la nuit précédante et jusqu'à la fin de la dialyse, et l'ordre d'administration des deux solutions était déterminé au hasard. Les acides aminés plasmatiques totaux, essentiels et non essentiels ont significativement diminué pendant la perfusion de soluté physiologique, et se sont élevés pendant l'administration d'acides aminés et de glucose. Dans le dialysat, les pertes totales d'acides aminés libres étaient en moyenne de 8,2 ± 3,1g (ds) pendant la perfusion de soluté physiologique, et de 12,6 ± 3,6g lors de l'administration d'acides aminés et de glucose. Ces résultats indiquent que la perfusion intraveineuse d'acides aminés et de glucose au cours de la dialyse empêche la chute des acides aminés et du glucose plasmatiques et n'occasionne qu'une diminution minime des pertes en acides aminés libres dans le dialysat. Puisque la plupart des acides aminés perfusés est retenue, cette technique pourrait être utilisée pendant l'hémodialyse pour éviter une fuite nette d'acides aminés, pour minimiser la dissipation des réserves d'acides aminés et de glucose et pour apporter un supplément nutritif