1,064,649 research outputs found
Factors associated with the performance and cost-effectiveness of using lymphatic filariasis transmission assessment surveys for monitoring soil-transmitted helminths: a case study in Kenya.
Transmission assessment surveys (TAS) for lymphatic filariasis have been proposed as a platform to assess the impact of mass drug administration (MDA) on soil-transmitted helminths (STHs). This study used computer simulation and field data from pre- and post-MDA settings across Kenya to evaluate the performance and cost-effectiveness of the TAS design for STH assessment compared with alternative survey designs. Variations in the TAS design and different sample sizes and diagnostic methods were also evaluated. The district-level TAS design correctly classified more districts compared with standard STH designs in pre-MDA settings. Aggregating districts into larger evaluation units in a TAS design decreased performance, whereas age group sampled and sample size had minimal impact. The low diagnostic sensitivity of Kato-Katz and mini-FLOTAC methods was found to increase misclassification. We recommend using a district-level TAS among children 8-10 years of age to assess STH but suggest that key consideration is given to evaluation unit size
Why Trade Associations Matter: Exploring Function, Meaning, and Influence
We explore the organizational characteristics of trade associations (TAs) and suggest theoretical approaches for undertaking research into or involving TAs in management and organization studies. Through emphasizing the role of TAs within and between industries and at the interface of business and society, we consider how TAs generate meaning and influence
Grading Practices and Considerations of Graduate Students at the Beginning of their Teaching Assignment
Research shows that expert-like approaches to problem-solving can be promoted
by encouraging students to explicate their thought processes and follow a
prescribed problem-solving strategy. Since grading communicates instructors'
expectations, teaching assistants' grading decisions play a crucial role in
forming students' approaches to problem-solving in physics. We investigated the
grading practices and considerations of 43 graduate teaching assistants (TAs).
The TAs were asked to grade a set of specially designed student solutions and
explain their grading decisions. We found that in a quiz context, a majority of
TAs noticed but did not grade on solution features which promote expert-like
approaches to problem-solving. In addition, TAs graded differently in quiz and
homework contexts, partly because of how they considered time limitations in a
quiz. Our findings can inform professional development programs for TAs
Cooperative cell motility during tandem locomotion of amoeboid cells.
Streams of migratory cells are initiated by the formation of tandem pairs of cells connected head to tail to which other cells subsequently adhere. The mechanisms regulating the transition from single to streaming cell migration remain elusive, although several molecules have been suggested to be involved. In this work, we investigate the mechanics of the locomotion ofDictyosteliumtandem pairs by analyzing the spatiotemporal evolution of their traction adhesions (TAs). We find that in migrating wild-type tandem pairs, each cell exerts traction forces on stationary sites (∼80% of the time), and the trailing cell reuses the location of the TAs of the leading cell. Both leading and trailing cells form contractile dipoles and synchronize the formation of new frontal TAs with ∼54-s time delay. Cells not expressing the lectin discoidin I or moving on discoidin I-coated substrata form fewer tandems, but the trailing cell still reuses the locations of the TAs of the leading cell, suggesting that discoidin I is not responsible for a possible chemically driven synchronization process. The migration dynamics of the tandems indicate that their TAs' reuse results from the mechanical synchronization of the leading and trailing cells' protrusions and retractions (motility cycles) aided by the cell-cell adhesions
"Private information of the Fed, predictability of stock returns and expected monetary policy"
Energy efficiency-spectral efficiency trade-off of transmit antenna selection
We investigate the energy efficiency-spectral efficiency (EE-SE) trade-off of transmit antenna selection/maximum ratio combining (TAS) scheme. A realistic power consumption model (PCM) is considered, and it is shown that using TAS can provide significant energy savings when compared to multiple-input multiple-output (MIMO) in the low to medium SE region, regardless the number of antennas, as well as outperform transmit beamforming scheme (MRT) for the entire SE range. For a fixed number of receive antennas, our results also show that the EE gain of TAS over MIMO becomes even greater as the number of transmit antennas increases. The optimal value of SE that maximizes the EE is obtained analytically, and confirmed by numerical results. Moreover, the influence of receiver correlation is also evaluated and it is shown that considering a non-realistic PCM can lead to mistakes when comparing TAS and MIMO
Documentation of Ancestral Caddo Ceramic Vessels from the Harold Williams Site (41CP10), Camp County, Texas
The Harold Williams site (41CP10) is a large ancestral Caddo community cemetery on Dry Creek in the Big Cypress Creek basin in Camp County, Texas. Caddo burials and associated ceramic vessel funerary offerings have been discovered and dug at the Harold Williams site since the 1940s, and in 1967 the Texas Archeological Society (TAS) held their annual field school at the site.
During the course of the 1967 TAS excavations in Area A and B, several burial features were encountered and excavated, and these had associated ceramic vessels and other grave goods. These vessels were illustrated and cursorily described by Turner and Smith, and they were from Late Caddo period Titus phase graves. Recently two boxes of TAS Field School materials from the Harold Williams site were re-examined at the Texas Archeological Research Laboratory, and a number of whole and partial Caddo ceramic vessels from the TAS work were re-discovered. I took the opportunity to examine and document these vessels in detail, and the results of these analyses are presented in this article
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