803 research outputs found
Termite resistance of DMDHEU-treated wood.
Four field trials were conducted with wood modified with dimethyloldihydroxy-ethyleneurea (DMDHEU) in contact with subterranean termites. Trials 1 to 3 were conducted with Coptotermes acinaciformis (Froggatt); 1 and 2 in south-east Queensland, and 3 in northern Queensland, Australia. Trial 4 was conducted in northern Queensland with Mastotermes darwiniensis (Froggatt). Four timber species (Scots pine, beech, Slash pine and Spotted gum) and two levels (1.3 M and 2.3 M) of DMDHEU were used. The tests were validated. DMDHEU successfully prevented damage by C. acinaciformis in south-east Queensland, but not in northern Queensland. It also did not protect the wood against M. darwiniensis. Except for beech in trial 4, DMDHEU led to reduced mass losses caused by termite attack compared to the unmodified feeder stakes. Slash pine (in trials 1 and 3) and Spotted gum (in trial 1) presented low mass losses. Modification of Scots pine was more effective against termite damage than the modification of beech
Building a QC Database of Meteorological Data from NASA KSC and the United States Air Force's Eastern Range
The National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC) Natural Environments Branch (EV44) provides atmospheric databases and analysis in support of space vehicle design and day-of-launch operations for NASA and commercial launch vehicle programs launching from the NASA Kennedy Space Center (KSC), co-located on the United States Air Force's Eastern Range (ER) at the Cape Canaveral Air Force Station. The ER complex is one of the most heavily instrumented sites in the United States with over 31 towers measuring various atmospheric parameters on a continuous basis. An inherent challenge with large datasets consists of ensuring erroneous data are removed from databases, and thus excluded from launch vehicle design analyses. EV44 has put forth great effort in developing quality control (QC) procedures for individual meteorological instruments, however no standard QC procedures for all databases currently exists resulting in QC databases that have inconsistencies in variables, development methodologies, and periods of record. The goal of this activity is to use the previous efforts to develop a standardized set of QC procedures from which to build meteorological databases from KSC and the ER, while maintaining open communication with end users from the launch community to develop ways to improve, adapt and grow the QC database. Details of the QC procedures will be described. As the rate of launches increases with additional launch vehicle programs, It is becoming more important that weather databases are continually updated and checked for data quality before use in launch vehicle design and certification analyses
Control of Columnar to Equiaxed Transition in Solidification Macrostructure of Austenitic Stainless Steel Castings
Solidification macrostructure is of great importance for the properties and the quality of castings made from austenitic grade stainless steels (ASS) because there are limited options to change as-cast macrostructure in the solid condition. A typical cast macrostructure of ASS has a fine surface chilled zone followed by an elongated dendrite zone, columnar to equiaxed transition (CET) zone, and centrally located equiaxed crystals. Several castings from ASS were produced to determine the effects of casting geometry, chilling, and grain refinement on CET. The transient thermal field in solidified heavy castings was simulated and used to determine an isotherm velocity (V) and the thermal gradient (G) in mushy zone at 50% solid fraction. The critical value of the parameter Gn/V was determined from the macrostructure of the cylindrical casting. Using this value, the location of CET was predicted in the heavy rectangular casting and this prediction was in agreement with experimental macrostructure. Two methods of controlling casting macrostructure by using a chilled mold to stimulate extensive columnar zone and by using melt grain refinement to produce fine equiaxed crystals were experimentally verified and simulated
An Evaluation of The Effectiveness of Adaptive Histogram Equalization for Contrast Enhancement
Adaptive Histogram Equalization (AHE), a method of contrast enhancement which is sensitive to local spatial information in an image, has been proposed as a solution to the problem of the inability of ordinary display devices to depict the full dynamic intensity range in some medical images. This method is automatic, reproducible, and simultaneously displays most of the information contained in the grey-scale contrast of the image. However, it has not been known whether the use of AHE causes the loss of diagnostic information relative to the commonly-used method intensity windowing. In the current work, AHE and intensity windowing are compared using psychophysical observer studies. In studies performed at North Carolina Memorial Hospital, experienced radiologists were shown clinical CT images of the chest. Into some of the images, appropriate artificial lesion were introduced; the physicians were then shown the images processed with both AHE and intensity windowing. They were asked to assess the probability that as given image contained the artificial lesion, and their accurate was measured. The results of these experiments shown that for this particular diagnostic task, there was no significant difference in the ability of the two methods to depict luminance contrast; thus, further evaluation of AHE using controlled clinical trials is indicated
Sorghum Association Panel whole-genome sequencing establishes cornerstone resource for dissecting genomic diversity
Association mapping panels represent foundational resources for understanding the genetic basis of phenotypic diversity and serve to advance plant breeding by exploring genetic variation across diverse accessions. We report the whole-genome sequencing (WGS) of 400 sorghum (Sorghum bicolor (L.) Moench) accessions from the Sorghum Association Panel (SAP) at an average coverage of 38× (25–72×), enabling the development of a high-density genomic marker set of 43 983 694 variants including single-nucleotide polymorphisms (approximately 38 million), insertions/deletions (indels) (approximately 5 million), and copy number variants (CNVs) (approximately 170 000). We observe slightly more deletions among indels and a much higher prevalence of deletions among CNVs compared to insertions. This new marker set enabled the identification of several novel putative genomic associations for plant height and tannin content, which were not identified when using previous lower-density marker sets. WGS identified and scored variants in 5-kb bins where available genotyping-by-sequencing (GBS) data captured no variants, with half of all bins in the genome falling into this category. The predictive ability of genomic best unbiased linear predictor (GBLUP) models was increased by an average of 30% by using WGS markers rather than GBS markers. We identified 18 selection peaks across subpopulations that formed due to evolutionary divergence during domestication, and we found six Fst peaks resulting from comparisons between converted lines and breeding lines within the SAP that were distinct from the peaks associated with historic selection. This population has served and continues to serve as a significant public resource for sorghum research and demonstrates the value of improving upon existing genomic resources
Task-specific facilitation of cognition by anodal transcranial direct current stimulation of the prefrontal cortex
We previously speculated that depression of cerebellar excitability using cathodal transcranial direct current stimulation (tDCS) might release extra cognitive resources via the disinhibition of activity in prefrontal cortex. The objective of the present study was to investigate whether anodal tDCS over the prefrontal cortex could similarly improve performance when cognitive demands are high. Sixty-three right-handed participants in 3 separate groups performed the Paced Auditory Serial Addition Task (PASAT) and the more difficult Paced Auditory Serial Subtraction Task (PASST), before and after 20 min of anodal, cathodal, or sham stimulation over the left dorsolateral prefrontal cortex (DLPFC). Performance was assessed in terms of the accuracy, latency, and variability of correct verbal responses. All behavioral measures significantly improved for the PASST after anodal DLPFC stimulation, but not the PASAT. There were smaller practice effects after cathodal and sham stimulation. Subjective ratings of attention and mental fatigue were unchanged by tDCS over time. We conclude that anodal stimulation over the left DLPFC can selectively improve performance on a difficult cognitive task involving arithmetic processing, verbal working memory, and attention. This result might be achieved by focally improving executive functions and/or cognitive capacity when tasks are difficult, rather than by improving levels of arousal/alertness
Beam stabilization in the two-dimensional nonlinear Schrodinger equation with an attractive potential by beam splitting and radiation
Mii-vitaliSe: a pilot randomised controlled trial of a home gaming system (Nintendo Wii) to increase activity levels, vitality and well-being in people with multiple sclerosis.
OBJECTIVES: While the health and well-being benefits of physical activity are recognised, people with multiple sclerosis (MS) often face greater barriers than the general population. The Nintendo Wii potentially offers a fun, convenient way of overcoming some of these. The aim was to test the feasibility of conducting a definitive trial of the effectiveness and cost-effectiveness of Mii-vitaliSe; a home-based, physiotherapist-supported Nintendo Wii intervention. DESIGN: A single-centre wait-list randomised controlled study. SETTING: MS service in secondary care. PARTICIPANTS: Ambulatory, relatively inactive people with clinically confirmed MS. INTERVENTION: Thirty participants were randomised to receive Mii-vitaliSe either immediately (for 12 months) or after a 6-month wait (for 6 months). Mii-vitaliSe consisted of two supervised Nintendo Wii familiarisation sessions in the hospital followed by home use (Wii Sports, Sports Resort and Fit Plus software) with physiotherapist support and personalised resources. OUTCOMES: Included self-reported physical activity levels, quality of life, mood, self-efficacy, fatigue and assessments of balance, gait, mobility and hand dexterity at baseline, 6 and 12 months. Interviews (n=25) explored participants' experiences and, at study end, the two Mii-vitaliSe facilitators' experiences of intervention delivery (main qualitative findings reported separately). RESULTS: Mean (SD) age was 49.3 (8.7) years, 90% female, with 47% diagnosed with MS <6 years ago and 60% new to active gaming. The recruitment rate was 31% (95% CI 20% to 44%). Outcome data were available for 29 (97%) at 6 months and 28 (93%) at 12 months. No serious adverse events were reported during the study. Qualitative data indicated that Mii-vitaliSe was well-received. Mean Wii use across both groups over the initial 6-month intervention period was twice a week for 27 min/day. Mean cost of delivering Mii-vitaliSe was £684 per person. DISCUSSION: Mii-vitaliSe appears acceptable and a future trial feasible and warranted. These findings will inform its design. TRIAL REGISTRATION: ISRCTN49286846
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