Experimental Data on Stagnation-Point Gas Injection Cooling on a Hemisphere-Cone in a Hypersonic Arc Tunnel

Exploratory tests were made to determine the reduction of heat transfer resulting from ejection of gases at the stagnation point on a hemisphere-cone at a nominal Mach number of about 9 and at stagnation enthalpies up to 1600 BTU per pound. Helium, nitrogen, and argon gases were used as coolants. The ratio of mass flow of coolant to the mass flow of air swept out by the model projected area was less than 0.20 in all cases. The experimental heat-transfer data were normalized by the calculated stagnation-point values based on test conditions in the tunnel and are presented as a function of the surface distance from the stagnation point. The variation of shock standoff distances with mass flow and volumetric flow of the gaseous ejectants is presented along with photographs of the luminous flow field of the model during tests

Do health investments improve agricultural productivity?

Determining the causality between health measures and both income and labor productivity remains an ongoing challenge for economists. This review paper aims to answer the question: Does improved population health lead to higher rates of agricultural growth? In attempting to answer this question, we survey the empirical literature at micro and macro levels concerning the link between health investments and agricultural productivity. The evidence from some micro-level studies suggests that inexpensive health interventions can have a very large impact on labor productivity. The macro-level evidence at the country and global level, however, is mixed at best and in some cases suggests that health care interventions have no impact on income, much less on agricultural productivity. At both micro and macro levels, the literature does not provide a clear-cut answer to the question under investigation. Overall, the review reveals a great deal of heterogeneity in terms of estimation methods, definition and measurement of health variables, choice of economic outcomes, single-equation versus multiple-equation approach, and static versus dynamic approach. The actual magnitude of estimated elasticities is difficult to assess in part due to estimation bias caused by the endogeneity of health outcomes. We also found significant gaps in the literature; for example, very little attention is given to demand for health inputs by rural populations and farmers.Agriculture, Growth, health, Investment, Nutrition, productivity,

Reference-free direct digital lock-in method and apparatus

A reference-free direct digital lock-in system (RDDL 10) has a first input coupled to a periodic electrical signal and an output for outputting an indication of a magnitude of a desired periodic signal component. The RDDL also has a second input for receiving a signal (9) that specifies a reference period value, and operates to autonomously generate a lock-in reference signal having a specified period and a phase that is adjusted to maximize a magnitude of the outputted desired periodic signal component. In an embodiment of a measurement system that includes the RDDL 10 an optical source provides a chopped light beam having wavelengths within a predetermined range of wavelengths, and the periodic electrical signal is generated by at least one photodetector that is illuminated by the chopped light beam. In this embodiment the measurement system characterizes, for at least one wavelength of light that is generated by the optical source, a spectral response of the at least one photodetector. The RDDL can operate in nonreal-time upon previously generated and stored digital equivalent values of the periodic electrical signal or signals

Jumble Java Byte Code to Measure the Effectiveness of Unit Tests

Jumble is a byte code level mutation testing tool for Java which inter-operates with JUnit. It has been designed to operate in an industrial setting with large projects. Heuristics have been included to speed the checking of mutations, for example, noting which test fails for each mutation and running this first in subsequent mutation checks. Significant effort has been put into ensuring that it can test code which uses custom class loading and reflection. This requires careful attention to class path handling and coexistence with foreign class-loaders. Jumble is currently used on a continuous basis within an agile programming environment with approximately 370,000 lines of Java code under source control. This checks out project code every fifteen minutes and runs an incremental set of unit tests and mutation tests for modified classes. Jumble is being made available as open source

Amesbury Early College Program: Second-Year Outcomes

This program involves creating five-year longitudinal community-based program evaluation reports annually based on outcomes for early college program for academically average students in grades 10-12, in a suburban high school partnership with MA community college. The Mixed methodology employed uses surveys and interviews and quantitative student data to illuminate program design, measure student outcomes, investigate changes in teaching practice and examine effective leadership practices. The two-year results show impressive credit accumulation and improved college readiness skills in students. It also shows that strong support mechanisms promote student success. This Program is now being replicated in other communities

Salivary Heterotopia Of The Parathyroid Gland: A Report of Two Cases and Review of the Literature

Two cases of periparathyroid salivary gland heterotopia are described. A review of the records of the Department of Pathology, Long Island Jewish Medical Center, over a 4-year period, identified 759 surgical specimens containing parathyroid gland tissue. Of these, 2 (0.26%) contained foci of ectopic salivary gland tissue. Both cases were associated with cyst formation. To date, 9 additional cases of heterotopic salivary gland tissue associated with the parathyroid gland have been described in the literature

Media multitasking in adolescence

Media use has been on the rise in adolescents overall, and in particular, the amount of media multitasking—multiple media consumed simultaneously, such as having a text message conversation while watching TV—has been increasing. In adults, heavy media multitasking has been linked with poorer performance on a number of laboratory measures of cognition, but no relationship has yet been established between media-multitasking behavior and real-world outcomes. Examining individual differences across a group of adolescents, we found that more frequent media multitasking in daily life was associated with poorer performance on statewide standardized achievement tests of math and English in the classroom, poorer performance on behavioral measures of executive function (working memory capacity) in the laboratory, and traits of greater impulsivity and lesser growth mindset. Greater media multitasking had a relatively circumscribed set of associations, and was not related to behavioral measures of cognitive processing speed, implicit learning, or manual dexterity, or to traits of grit and conscientiousness. Thus, individual differences in adolescent media multitasking were related to specific differences in executive function and in performance on real-world academic achievement measures: More media multitasking was associated with poorer executive function ability, worse academic achievement, and a reduced growth mindset.Bill & Melinda Gates Foundatio