Commitment during stenotele differentiation in Hydra is localized near the S/G2 boundary in the terminal cell cycle

The timing of commitment during stenotele differentiation in Hydra was determined. Regeneration of isolated distal regions of the body column induces stenotele differentiation. The kinetics of appearance of committed stenotele precursors was determined in such regenerating pieces. Using [3H]thymidine labeling and hydroxyurea sensitivity, the G1/S and the S/G2 boundaries of the precursor population was also determined. Comparison of these results indicates that stenotele commitment is localized near the S/G2 boundary in the terminal cell cycle of nests of precursor cells

Welfare Time Limits: An Update on State Policies, Implementation, and Effects on Families

One of the most controversial features of the 1990s welfare reforms was the imposition of time limits on benefit receipt. This comprehensive review, written by The Lewin Group and MDRC, includes analyses of administrative data reported by states to the federal government, visits to several states, and a literature review

Effects of a Heated Turbulent Boundary Layer on Surface Pressure Fluctuations

Recent work has shown that spatial correlation of surface pressure fluctuations in a fully turbulent atmospheric boundary layer (ABL) can give information about the velocity field and turbulence. This is of particular importance to the future of wind energy to predict the incoming velocity flow field of wind turbines so as to actively control them for peak operating efficiency and damage reduction. All of the environmental effects on the surface pressure fluctuations need to be fully understood before a suitable flow prediction algorithm can be constructed. One such environmental effect which has not been previously studied is the effect of surface heating on the surface pressure fluctuations. The current study aims to create a situation in a low speed wind tunnel that is roughly analogous to that of a ground heated turbulent ABL and to study the effects on the surface pressure fluctuations. The intent was not to perfectly scale the ABL but to create a situation in the wind tunnel that mimics some of the same physical processes associated with the ABL. Experimental data was collected in the 2\u27x2\u27 square test section low speed wind tunnel at the University of Mississippi\u27s National Center for Physical Acoustics. A 3 tall backward facing step was placed at the entrance of the test section to create a sufficiently thick, fully developed turbulent boundary layer further down the test section where surface pressure fluctuations were measured. The bottom floor of the tunnel was also retrofitted with electric heater blankets so as to study the effect of surface heating on the surface pressure fluctuations. The effect of heating on surface pressure fluctuations was studied for a variety of flow speeds and surface temperatures and it was shown that the surface heating had little to no effect on any of the measurements of the sound pressure level beneath the boundary layer. It was also shown from the cross-correlation coefficient functions that the surface heating had little to no effect on the calculated turbulent convection speeds

On-site application of self-compacting concrete (SCC)

Self-Compacting Concrete (SCC) is a material which under its own self-weight flows to form and fill any shape, attains full compaction, without external energy input, to create a dense homogenous mass (based on Holton, 2003; The Concrete Society and BRE, 2005; Damtoft et al, 2008). It is, in respect to the history of concrete, a relatively new development, with its first UK application occurring in the late 1990s. Since then a significant amount of research has sought to understand its physical and structural properties, but there is a lack of a knowledge base on its practical application and performance in construction projects. Where it does exist, such research lacks robust and transparent data, particularly relating to the claimed attributes of the material (such as better surface finish, faster construction and lower overall costs). Using a combination of qualitative and quantitative research methods, this research investigates the construction practices employed when pouring SCC and presents new data on its practical applications. Interviews with a range of building contractors, ranging from multinationals to small UK businesses (SMEs), show that current perceptions of SCC limit its use to specific applications because practitioners see SCC as just another type of concrete . A critical examination of these attitudes led to the identification of three distinct scenarios for the use of SCC: 1. Reactive selection: in which a particular attribute of SCC provokes its use to solve a particular problem, often as a last minute substitution for conventional concrete the most common scenario. 2. Strategic change: in which the material is chosen on the basis of a balanced assessment of all its benefits and on the understanding that such benefits can only be attained if the contractor appreciates that there may be implications for the construction process a rarely experienced scenario. 3. Specification: in which there is complete acceptance of SCC as a method, not just as a material; a significant amount of early project involvement with knowledge holders, such as contractors and material suppliers, optimises the construction process. A rigorous work measurement study of live construction projects has made it possible to quantify the as-built costs of SCC for selected UK residential slab and multi-storey flat slab applications and compare this with the equivalent conventional concrete slab construction. On-site use of self-compacting concrete vi The results indicate that SCC can reduce construction times of structural topping layers of residential slabs by up to 73%, and has shown that SCC can also match, if not reduce, total as-built concrete placement costs in multi-storey applications. This new data will enable contractors, designers and specifiers to better understand the practical implications of using SCC for on-site applications, thereby leading to more potential instances of its early and planned specification, hence resulting in more of its full benefits being realised

SPARSE FORWARD-BACKWARD ALIGNMENT FOR SENSITIVE DATABASE SEARCH WITH SMALL MEMORY AND TIME REQUIREMENTS

Sequence annotation is typically performed by aligning an unlabeled sequence to a collection of known sequences, with the aim of identifying non-random similarities. Given the broad diversity of new sequences and the considerable scale of modern sequence databases, there is significant tension between the competing needs for sensitivity and speed, with multiple tools displacing the venerable BLAST software suite on one axis or another. In recent years, alignment based on profile hidden Markov models (pHMMs) and associated probabilistic inference methods have demonstrated increased sensitivity due in part to consideration of the ensemble of all possible alignments between a query and target using the Forward/Backward algorithm, rather than simply relying on the single highest-probability (Viterbi) alignment. Modern implementations of pHMM search achieve their speed by avoiding computation of the expensive Forward/Backward algorithm for most (HMMER3) or all (MMseqs2) candidate sequence alignments. Here, we describe a heuristic Forward/Backward algorithm that avoids filling in the entire quadratic dynamic programming (DP) matrix, by identifying a sparse cloud of DP cells containing most of the probability mass. The method produces an accurate approximation of the Forward/Backward alignment with high speed and small memory requirements. We demonstrate the utility of this sparse Forward/Backward approach in a tool that we call MMOREseqs; the name is a reference to the fact that our tool utilizes the MMseqs2 software suite to rapidly identify promising seed alignments to serve as a basis for sparse Forward/Backward. MMOREseqs demonstrates improved annotation sensitivity with modest increase in run time over MMseqs2 and is released under the open BSD-3-clause license. Source code and Docker image are available for download at https://github.com/TravisWheelerLab/MMOREseqs

Stink Bugs (Hemiptera: Heteroptera: Pentatomidae) of Minnesota: An Annotated Checklist and New State Records

Pentatomidae have been relatively poorly documented in Minnesota. Based on literature and museum records, an annotated checklist of the Pentatomidae of Minnesota was created. State-level and county-level records for Minnesota and the distribution of each species in North America are provided. Fifty-one species of Pentatomidae (12 Asopinae, 37 Pentatominae, and 2 Podopinae) are recorded for Minnesota. Of this total, 15 species are newly recorded for the state. Knowledge of the fauna of Pentatomidae in Minnesota will be important for providing baseline data for monitoring of potential shifts in the fauna resulting from the invasions of exotic Pentatomidae. Furthermore, a list of native Pentatomidae will be necessary for monitoring non-target impacts, if classical biological control is implemented for management of exotic Pentatomidae

A Backend Framework for the Efficient Management of Power System Measurements

Increased adoption and deployment of phasor measurement units (PMU) has provided valuable fine-grained data over the grid. Analysis over these data can provide insight into the health of the grid, thereby improving control over operations. Realizing this data-driven control, however, requires validating, processing and storing massive amounts of PMU data. This paper describes a PMU data management system that supports input from multiple PMU data streams, features an event-detection algorithm, and provides an efficient method for retrieving archival data. The event-detection algorithm rapidly correlates multiple PMU data streams, providing details on events occurring within the power system. The event-detection algorithm feeds into a visualization component, allowing operators to recognize events as they occur. The indexing and data retrieval mechanism facilitates fast access to archived PMU data. Using this method, we achieved over 30x speedup for queries with high selectivity. With the development of these two components, we have developed a system that allows efficient analysis of multiple time-aligned PMU data streams.Comment: Published in Electric Power Systems Research (2016), not available ye