Soybean cyst nematode disease

Microscopic worms burrowing through cells, injecting foreign compounds through hypodermic-needle-like structures, altering the basic biology of the cells being fed upon. Worms that grow so large in just a few weeks that they rupture out of the tissue they are feeding upon. Sound like a science fiction movie plot? Believe it or not, it is the basic biology of a widespread, serious pathogen of soybeans - the soybean cyst nematode

Airborne sulfur trace species intercomparison campaign: Sulfur dioxide, dimethylsulfide, hydrogen sulfide, carbon disulfide, and carbonyl sulfide

Results from an airborne intercomparison of techniques to measure tropospheric levels of sulfur trace gases are presented. The intercomparison was part of the NASA Global Tropospheric Experiment (GTE) and was conducted during the summer of 1989. The intercomparisons were conducted on the Wallops Electra aircraft during flights from Wallops Island, Virginia, and Natal, Brazil. Sulfur measurements intercompared included sulfur dioxide (SO2), dimethylsulfide (DMS), hydrogen sulfide (H2S), carbon disulfide (CS2), and carbonyl sulfide (OCS). Measurement techniques ranged from filter collection systems with post-flight analyses to mass spectrometer and gas chromatograph systems employing various methods for measuring and identifying the sulfur gases during flight. Sampling schedules for the techniques ranged from integrated collections over periods as long as 50 minutes to one- to three-minute samples every ten or fifteen minutes. Several of the techniques provided measurements of more than one sulfur gas. Instruments employing different detection principles were involved in each of the sulfur intercomparisons. Also included in the intercomparison measurement scenario were a host of supporting measurements (i.e., ozone, nitrogen oxides, carbon monoxide, total sulfur, aerosols, etc.) for purposes of: (1) interpreting results (i.e., correlation of any noted instrument disagreement with the chemical composition of the measurement environment); and (2) providing supporting chemical data to meet CITE-3 science objectives of studying ozone/sulfur photochemistry, diurnal cycles, etc. The results of the intercomparison study are briefly discussed

ESTIMATED COSTS AND RETURNS FOR CATFISH FARMS WITH RECIRCULATING PONDS ALONG THE UPPER TEXAS COAST

Cost, returns, and economies of scale for small, medium and large catfish farms with recirculating ponds are presented for the upper Texas coast. Internal rates of return are 0.150, 0.183 and 0.219, respectively. Total investment is higher than farms with static ponds but investment per unit production capacity is 7 percent to 16 percent lower. Average total cost per pound is between $0.565 and$0.541, (11 percent –20 percent lower than farms using current technology). These results have implications for regional comparative advantage of catfish production as well as incentive for adoption of new technology in conventional ponds.Aquaculture, Catfish, Economics, Off-flavor, Livestock Production/Industries,

Media treatment of an environmental problem -- did they accurately report the key issues of Cheyenne Bottoms Waterfowl Management Area, according to the experts?: a content analysis of area newspapers

Call number: LD2668 .R4 JMC 1988 D38Master of ScienceJournalism and Mass Communication

Complexity in an Unexpected Place: Quantities in Selected Acquisition Reports

We have looked at the definition of units in numerous acquisition programs and discovered that the units reported are almost never simple; in some programs, no two units are the same, and almost invariably the units produced at the end of a long production run are substantially different from the early ones. We have identified three reasons why the units may differ. The first reason is changes over time, generally as system capabilities are improved. The second is due to mixed types, where units that are inherently dissimilar;such as CH-47F and MH-47G helicopters;are produced by the same program and each is called one unit. The final reason why units can differ is reporting accidents. We give examples of all three and discuss possible methods of improving the reporting requirement.Naval Postgraduate School Acquisition Research Progra

Castable Amorphous Metal Mirrors and Mirror Assemblies

A revolutionary way to produce a mirror and mirror assembly is to cast the entire part at once from a metal alloy that combines all of the desired features into the final part: optical smoothness, curvature, flexures, tabs, isogrids, low CTE, and toughness. In this work, it has been demonstrated that castable mirrors are possible using bulk metallic glasses (BMGs, also called amorphous metals) and BMG matrix composites (BMGMCs). These novel alloys have all of the desired mechanical and thermal properties to fabricate an entire mirror assembly without machining, bonding, brazing, welding, or epoxy. BMGs are multi-component metal alloys that have been cooled in such a manner as to avoid crystallization leading to an amorphous (non-crystalline) microstructure. This lack of crystal structure and the fact that these alloys are glasses, leads to a wide assortment of mechanical and thermal properties that are unlike those observed in crystalline metals. Among these are high yield strength, carbide-like hardness, low melting temperatures (making them castable like aluminum), a thermoplastic processing region (for improving smoothness), low stiffness, high strength-to-weight ratios, relatively low CTE, density similar to titanium alloys, high elasticity and ultra-smooth cast parts (as low as 0.2-nm surface roughness has been demonstrated in cast BMGs). BMGMCs are composite alloys that consist of a BMG matrix with crystalline dendrites embedded throughout. BMGMCs are used to overcome the typically brittle failure observed in monolithic BMGs by adding a soft phase that arrests the formation of cracks in the BMG matrix. In some cases, BMGMCs offer superior castability, toughness, and fatigue resistance, if not as good a surface finish as BMGs. This work has demonstrated that BMGs and BMGMCs can be cast into prototype mirrors and mirror assemblies without difficulty

Efficacy of Blended E-Learning Tools: A Case Study

In the past 5 years, interest in distance learning has increased, and use of e-learning tools has become more widely accepted by academics. With such a wide variety of e-learning tools to choose from, what really works? How might we augment our traditional teaching tools with a blend of the new e-learning tools to better reach audiences? In this article, we discuss the efficacy of a set of blended e-learning tools — blogs, podcasts, enhanced podcasts, Internet telephony and instant messaging, news aggregators, collaborative project management software, and Web/video conferencing — used to teach Ohio State University (OSU) professionals about knowledge economy programming. We share implications of survey findings from this population and provide recommendations for others interested in initiating or improving their distance learning efforts with these tools

Mapping the contribution of Allied Health Professions to the wider public health workforce : a rapid review of evidence-based interventions

Objectives: The objective was to identify a selection of the best examples of the public health contributions by Allied Health Professionals (AHPs) in order to encourage a wider awareness and participation from that workforce to public health practice. Study design: A mapping exercise was used to identify evidence-based interventions that could lead to health improvements across a population. Methods: A rapid review was undertaken to identify evidence, followed by a survey of Allied Health Profession (AHP) practitioners and an expert panel consensus method to select the examples of AHP public health interventions. Results: Nine evidence-based interventions are identified and selected as examples of current AHP good practice. These examples represent a contribution to public health and include screening interventions, secondary prevention and risk management. Conclusions: This study contributes to a strategy for AHPs in public health by appraising the effectiveness and impact of some exemplar AHP practices that contribute to health improvement. There is a need for AHPs to measure the impact of their interventions and to demonstrate evidence of outcomes at population level. Keywords: allied health professions; Applied Health Professionals; evidence-based practice; health improvement; public health; rapid revie

Early respiratory viral infections in infants with cystic fibrosis

This article is made available for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic.Background Viral infections contribute to morbidity in cystic fibrosis (CF), but the impact of respiratory viruses on the development of airway disease is poorly understood. Methods Infants with CF identified by newborn screening were enrolled prior to 4 months of age to participate in a prospective observational study at 4 centers. Clinical data were collected at clinic visits and weekly phone calls. Multiplex PCR assays were performed on nasopharyngeal swabs to detect respiratory viruses during routine visits and when symptomatic. Participants underwent bronchoscopy with bronchoalveolar lavage (BAL) and a subset underwent pulmonary function testing. We present findings through 8.5 months of life. Results Seventy infants were enrolled, mean age 3.1 ± 0.8 months. Rhinovirus was the most prevalent virus (66%), followed by parainfluenza (19%), and coronavirus (16%). Participants had a median of 1.5 viral positive swabs (range 0–10). Past viral infection was associated with elevated neutrophil concentrations and bacterial isolates in BAL fluid, including recovery of classic CF bacterial pathogens. When antibiotics were prescribed for respiratory-related indications, viruses were identified in 52% of those instances. Conclusions Early viral infections were associated with greater neutrophilic inflammation and bacterial pathogens. Early viral infections appear to contribute to initiation of lower airway inflammation in infants with CF. Antibiotics were commonly prescribed in the setting of a viral infection. Future investigations examining longitudinal relationships between viral infections, airway microbiome, and antibiotic use will allow us to elucidate the interplay between these factors in young children with CF

Measurements of pernitric acid at the South Pole during ISCAT 2000

The first measurements of pernitric acid at the South Pole were performed during the second Investigation of Sulfur Chemistry in the Antarctic Troposphere (ISCAT 2000). Observed HO2NO2 concentrations averaged 25 pptv. Simple steady-state calculations constrained by measurements show that the lifetime of pernitric acid was largely controlled by dry deposition, with thermal decomposition becoming increasingly important at warmer temperatures. We determined that the pernitric acid equilibrium constant is less uncertain than indicated in the literature. One consequence of pernitric acid deposition to the snow surface is that it is an important sink for both NOx and HOx. Another is that the photochemistry of HO2NO2 in the Antarctic snowpack may be a NOx source in addition to nitrate photolysis. This might be one of the important differences in snow photochemistry between the South Pole and warmer polar sites