Experimental Observation of Modulation Instability and Optical Spatial Soliton Arrays in Soft Condensed Matter

In this Letter we report observations of optically induced self-organization of colloidal arrays in the presence of un-patterned counter-propagating evanescent waves. The colloidal arrays formed along the laser propagation-axis are shown to be linked to the break-up of the incident field into optical spatial solitons, the lateral spacing of the arrays being related to modulation instability of the soft condensed matter system.Comment: 16 pages, 3 figure

Superconducting Surface Impedance under Radiofrequency Field

Based on BCS theory with moving Cooper pairs, the electron states distribution at 0K and the probability of electron occupation with finite temperature have been derived and applied to anomalous skin effect theory to obtain the surface impedance of a superconductor under radiofrequency (RF) field. We present the numerical results for Nb and compare these with representative RF field-dependent effective surface resistance measurements from a 1.5 GHz resonant structure

The Kansas Legislature: Structure and Process

Many Kansans view the legislative process as a disordered hodgepodge of events that somehow magically results in new rules for our society, enacted as "laws." In reality, however, the legislative process is finely controlled and dictated by law, rules, and tradition. While public policy issues and priorities have changed throughout Kansas' history as a state, the general provisions governing the creation of state laws have remained unaltered

Barbell back squat:How do resistance bands affect muscle activation and knee kinematics?

ObjectivesThis study aimed to determine whether looped resistance bands affect knee kinematics and lower body muscle activation during the barbell back squat.MethodsTwenty-six healthy participants (13 female, 13 male) calculated their one repetition maximum (RM) prior to data collection. Each participant performed three squats at both 80% and 40% 1RM wearing a light resistance band, an extra-heavy resistance band and no resistance band.Vicon 3D motion analysis cameras were used to collect the kinematic data, and Delsys Trigno Lab wireless electromyography (EMG) system was used to measure vastus medialis, vastus lateralis, gluteus maximus, gluteus medius and biceps femoris muscle activity. Peak knee flexion angle, peak knee valgus angle and maximum tibial rotation values were examined. Peak EMG values were also analysed after being normalised and expressed as a percentage of maximum voluntary contraction (MVC).ResultsGluteus maximus (GM) activity is significantly increased when a resistance band is used during squatting. However, squatting with a resistance band is detrimental to knee kinematics as it leads to an increase in knee valgus angle and maximum tibial rotation angle. A direct correlation is recorded between an increase in resistance and an increase in these two angles.ConclusionsSquatting with resistance bands is likely to increase the risk of knee injury. Coaches and clinicians who already implement this technique are advised to remove resistance band squats from training and rehabilitation programmes. Further research evaluating the long-term effects of using resistance bands during the barbell back squat should be considered

EC85-198 Nebraska Poisonous Range Plants

Extension Circular 85-198: Nebraska Poisonous Range Plants. This circular helps people identify plants that grow in Nebraska that may be poisonous

EC85-198 Nebraska Poisonous Range Plants

Extension Circular 85-198: Nebraska Poisonous Range Plants. This circular helps people identify plants that grow in Nebraska that may be poisonous

Performance and Potential of Intergeneric Wheatgrass Hybrids in the Central Great Plains

Three studies were conducted to evaluate intergeneric wheatgrass hybrids for their potential as range and pasture grasses in the Central Great Plains. Quackgrass [Elytriga-repens (L.) Nevski] X bluebunch wheatgrass [Psueodoroegneria spicata (Pursh) A. LoveJ F5 hybrid lines (RS lines) developed by D.R. Dewey were grown in a space transplanted nursery at Lincoln, NE, to estimate genetic variability for forage yield and quality as measured by in vitro dry matter digestibility (IVDMD) and protein in the RS population. There was significant variability among the RS lines for all traits (broad-sense heritability H \u3e 0.5) except for first harvest IVDMD (H = 0.26). The highest yielding RS lines yielded only about half as much forage as \u27Slate\u27 intermediate wheatgrass [Thinopyron intermedium (Host) Barkworth and D.R. Dewey subsp. intermedium], which was included as a check. Slate intermediate wheatgrass, \u27Ruff crested wheatgrass [Agropyron cristatum (L.) Gaertner], \u27Nordan\u27 crested wheatgrass [A. desertorum (Fisch.) SchultesJ, RS-1 and RS-2 (quackgrass X bluebunch wheatgrass germplasm), and a quackgrass X A. desertorum hybrid designated as RD were then evaluated in sward nurseries in two environments (Mead and Alliance, NE) that differ widely in climate. Intermediate wheatgrass was clearly superior in forage yield and quality as measured by IVDMD in the eastern part (Mead) of the Central Great Plains. In the western part of this area (Alliance) intermediate and the crested wheatgrasses were equal or superior to the RS hybrids in forage yield and intermediate wheatgrass had higher IVDMD. The RD hybrid had lower yields than the other strains at both locations. Yields of the intergeneric wheatgrass hybrids could be improved by breeding to make them more competitive with intermediate and crested wheatgrasses. The same breeding effort could be used to improve these pure species for which substantial genetic variability for both yield and IVDMD has been previously documented and would probably result in greater overall progress. Forages from grasses grown at Mead in swards were analyzed using the detergent system of analyses and there was considerable variation among the grasses in fiber composition and digestibility of the fiber components even though the grasses were very similar in physiological maturity when harvested. The results suggest that there are genetic differences among these wheatgrasses in forage fiber composition and the digestibility of the fiber components

Genotype and Genotype X Environment Interaction Effects on Forage Yield and Quality of Crested Wheatgrasses

Genotype, environment, and genotype X environment interaction effects for forage yield and quality of the crested wheatgrasses (Agropyron cristatum) and (A. desertorum) were studied using an array of 42 crested wheatgrass introductions, experimental lines, and released cultivars that were selected to be representative of the mix of germplasm available to a breeder. They were grown in two environments, Lincoln and Alliance, Nebr., that differ markedly in climate. Forage yield and forage quality as measured by in vitro dry matter digestibility (IVDMD) and percent protein were determined in both locations in 1980 and 1981. In the combined analyses over years and locations, there were significant differences among strains or genotypes and locations for first-harvest forage yield, IVDMD, and protein. Strain X location interaction effects were significant only for first-harvest forage yield and for this trait its variance component was only 0.3 as large as the variance component for strains. Strain X year interaction effects were not significant. Spearmen correlations, used to show relative ranking of the strains at the two locations, were moderate and positive for all first-cut traits. The results indicate that existing genetic variability in forage yield and quality should permit the development of improved crested wheatgrasses and that at least in the initial stages of a breeding program, selection for these traits could be done in a single location and year

Genotype and Genotype X Environment Interaction Effects on Forage Yield and Quality of Crested Wheatgrasses

Genotype, environment, and genotype X environment interaction effects for forage yield and quality of the crested wheatgrasses (Agropyron cristatum) and (A. desertorum) were studied using an array of 42 crested wheatgrass introductions, experimental lines, and released cultivars that were selected to be representative of the mix of germplasm available to a breeder. They were grown in two environments, Lincoln and Alliance, Nebr., that differ markedly in climate. Forage yield and forage quality as measured by in vitro dry matter digestibility (IVDMD) and percent protein were determined in both locations in 1980 and 1981. In the combined analyses over years and locations, there were significant differences among strains or genotypes and locations for first-harvest forage yield, IVDMD, and protein. Strain X location interaction effects were significant only for first-harvest forage yield and for this trait its variance component was only 0.3 as large as the variance component for strains. Strain X year interaction effects were not significant. Spearmen correlations, used to show relative ranking of the strains at the two locations, were moderate and positive for all first-cut traits. The results indicate that existing genetic variability in forage yield and quality should permit the development of improved crested wheatgrasses and that at least in the initial stages of a breeding program, selection for these traits could be done in a single location and year

Evaluation of Crested Wheatgrass Introductions for Forage Yield and Quality

Crested wheatgrass, Agropyron cristatum and A. desertorum, are among the most important cool-season forage grasses in the United States and Canada, particularly for reseeding arid range sites. Further improvement in this grass by breeding depends on identifying sources of genetic variability for forage yield and quality. Foreign introductions are an obvious source of genetic variation since crested wheatgrasses are introduced species. In this study 38 accessions (PI lines) and 8 Nebraska experimental lines were evaluated for forage quality as measured by in vitro dry matter digestibility (IVDMD) and protein content and for forage yield. The cultivars \u27Ruff\u27 and \u27Nordan\u27 and two clonal lines were included as checks. The strains were evaluated at Lincoln and Alliance, NE., which differ markedly in climate. There were large differences among strains evaluated for all traits including first- and second-cut forage yield, IVDMD, protein content, heading date, height and first year basal spread. Utilization of PI 369167, PI 369170, Ruff, and Nordan in a breeding program could result in crested wheatgrasses with improved forage yield and quality