Dynamic valve to supply constant total thrust to two orifice jets

Valve, maintaining constant total flow, is driven mechanically in periodic alterations to yield correspondingly periodic outputs of constant sum. Design is applicable to development of jet flaps for helicopter use and may be useful in a multinozzle system

On the evolution of snow roughness during snow fall

The deposition and attachment mechanism of settling snow crystals during snowfall dictates the very initial structure of ice within a natural snowpack. In this letter we apply ballistic deposition as a simple model to study the structural evolution of the growing surface of a snowpack during its formation. The roughness of the snow surface is predicted from the behaviour of the time dependent height correlation function. The predictions are verified by simple measurements of the growing snow surface based on digital photography during snowfall. The measurements are in agreement with the theoretical predictions within the limitations of the model which are discussed. The application of ballistic deposition type growth models illuminates structural aspects of snow from the perspective of formation which has been ignored so far. Implications of this type of growth on the aerodynamic roughness length, density, and the density correlation function of new snow are discusse

A modified least-squares collocation method for the determination of crustal deformation: first results in the Swiss Alps

The calculation of recent crustal movements and the associated crustal deformation rely on a suitable interpolation of geodetic measurements with repetition cycles of years or decades and modern GPS permanent networks. A common interpolation methods is the least-square collocation (LSC). LSC requires some a priori assumptions about the characteristics of the velocity field, that is, stocasticity in Moritz's definition of LSC. We present a novel approach, called adaptative LSC (ALSC) to the interpolation of non-stochastic fields, which encompass the traditional LSC and the block model as special cases. This modified collocation method is based on the empirical estimation of a anisotropic and inhomogeneous covariance function of the interpolated field. The method has been tested on synthetic data that simulate geodetic measurements over a triple plate junction and with real data from precise levelling measurements over the Swiss Alps. In both cases, ALSC gave better and more stable results, compared to LSC and other interpolation methods, such as smoothed spline

An Early-Planted, Early Maturing Soybean Cropping System: Yield and Harvest Losses

Most soybean varieties used In Kentucky, whether grown full season or double-cropped behind wheat or barley, are from Maturity Groups (MG) IV or V. Some MG III varieties are also grown; however, virtually no MG 1/ or earner varieties are planted. Agronomists and soybean producers in Kentucky· have generally felt that MG IV and V varieties produce the highest yield. Since the driest months in Kentucky are August, September,and October, MG IV and V varieties frequently encounter moisture stress during the important seed fill stage. The use of earlier maturing varieties was initially proposed as a means of getting a major portion of seed fill to occur before the driest part of the growing season, thus getting higher yields in dry years

Effect of Heavy Metal Contaminated Shooting Range Soils on Mycorrhizal Colonization of Roots and Metal Uptake by Leek

We grew leek (Allium porrum) in soils of two shooting ranges heavily contaminated with heavy metals in the towns of Zuchwil and Oberuzwil in Switzerland as a bioassay to test theactivity of arbuscular mycorrhizal (AM) fungi in these soils.Soil samples were taken from (1) front of the shooting house(HOUSE), (2) the area between house and target (FIELD) and (3) the berm (BACKSTOP). Samples of Ribwort plantain (Plantagolanceolata) growing naturally within the shooting ranges werealso collected and the colonization of its roots by mycorrhizalfungi was measured. The number of AM spores in the soils wassignificantly reduced concomitant with the increase in thedegree of soil contamination with metals. In Zuchwil,mycorrhizal fungi equally colonized roots of Ribwort plantainsampled from BACKSTOP and HOUSE. In Oberuzwil, however, plantsfrom BACKSTOP had lower colonization when compared with thosesampled from HOUSE. Colonization of leek was strongly reducedin the BACKSTOP soil of Zuchwil and slightly reduced in theBACKSTOP soil of Oberuzwil when compared with plants grown inrespective HOUSE soil. Concentrations of Cd, Cr, Cu, Ni, Pb andZn in the leaves of leek grown in the BACKSTOP soil was withinthe range considered toxic for human consumption. This pointsto the high degree of bio-availability of these metal in thesesoils. Significant decrease in the number of mycorrhizal sporesin the BACKSTOP soils in Zuchwil and the low colonization ofleek roots grown in these soils point to possible changes inthe species diversity of mycorrhizal fungi in these soil

Lack of associations between female hormone levels and visuospatial working memory, divided attention and cognitive bias across two consecutive menstrual cycles

Background: Interpretation of observational studies on associations between prefrontal cognitive functioning and hormone levels across the female menstrual cycle is complicated due to small sample sizes and poor replicability. Methods: This observational multisite study comprised data of n = 88 menstruating women from Hannover, Germany, and Zurich, Switzerland, assessed during a first cycle and n = 68 re-assessed during a second cycle to rule out practice effects and false-positive chance findings. We assessed visuospatial working memory, attention, cognitive bias and hormone levels at four consecutive time-points across both cycles. In addition to inter-individual differences we examined intra-individual change over time (i.e., within-subject effects). Results: Estrogen, progesterone and testosterone did not relate to inter-individual differences in cognitive functioning. There was a significant negative association between intra-individual change in progesterone and change in working memory from pre-ovulatory to mid-luteal phase during the first cycle, but that association did not replicate in the second cycle. Intra-individual change in testosterone related negatively to change in cognitive bias from menstrual to pre-ovulatory as well as from pre-ovulatory to mid-luteal phase in the first cycle, but these associations did not replicate in the second cycle. Conclusions: There is no consistent association between women’s hormone levels, in particular estrogen and progesterone, and attention, working memory and cognitive bias. That is, anecdotal findings observed during the first cycle did not replicate in the second cycle, suggesting that these are false-positives attributable to random variation and systematic biases such as practice effects. Due to methodological limitations, positive findings in the published literature must be interpreted with reservation

Effects of rain shelter or simulated rain during grain filling and maturation on subsequent wheat grain quality in the UK

The effects of simulated additional rain (ear wetting, 25 mm) or of rain shelter imposed at different periods after anthesis on grain quality at maturity and the dynamics of grain filling and desiccation were investigated in UK field-grown crops of wheat (Triticum aestivum L., cvar Tybalt) in 2011 and in 2012 when June–August rainfall was 255.0 and 214.6 mm, respectively, and above the decadal mean (157.4 mm). Grain filling and desiccation were quantified well by broken-stick regressions and Gompertz curves, respectively. Rain shelter for 56 (2011) or 70 d (2012) after anthesis, and to a lesser extent during late maturation only, resulted in more rapid desiccation and hence progress to harvest maturity whereas ear wetting had negligible effects, even when applied four times. Grain-filling duration was also affected as above in 2011, but with no significant effect in 2012. In both years, there were strong positive associations between final grain dry weight and duration of filling. The treatments affected all grain quality traits in 2011: nitrogen (N) and sulphur (S) concentrations, N:S ratio, sodium dodecyl sulphate (SDS) sedimentation volume, Hagberg Falling Number (HFN), and the incidence of blackpoint. Only N concentration and blackpoint were affected significantly by treatments in 2012. Rain shelter throughout grain filling reduced N concentration, whereas rain shelter reduced the incidence of blackpoint and ear wetting increased it. In 2011, rain shelter throughout reduced S concentration, increased N:S ratio and reduced SDS. Treatment effects on HFN were not consistent within or between years. Nevertheless, a comparison between the extreme treatment means in 2012 indicated damage from late rain combined with ear wetting resulted in a reduction of c. 0.7 s in HFN/mm August rainfall, whilst that between samples taken immediately after ear wetting at harvest maturity or 7 d later suggested recovery from damage to HFN upon re-drying in planta. Hence, the incidence of blackpoint was the only grain quality trait affected consistently by the diverse treatments. The remaining aspects of grain quality were comparatively resilient to rain incident upon developing and maturing ears of cvar Tybalt. No consistent temporal patterns of sensitivity to shelter or ear wetting were detected for any aspect of grain quality

Reactions of alpha,beta-unsaturated Thioamides with Diazo compounds

Several reactions of the a,b-unsaturated thioamide 8 with diazo compounds 1a–1d were investigated. The reactions with CH2N2 (1a), diazocyclohexane (1b), and phenyldiazomethane (1c) proceeded via a 1,3-dipolar cycloaddition of the diazo dipole at the C=C bond to give the corresponding 4,5-dihydro-1H-pyrazole-3-carbothioamides 12a–12c, i.e., the regioisomer which arose from the bond formation between the N-terminus of the diazo compound and the C(alpha)-atom of 8. In the reaction of 1a with 8, the initially formed cycloadduct, the 4,5-dihydro-3H-pyrazole-3-carbothioamide 11a, was obtained after a short reaction time. In the case of 1c, two tautomers 12c and 12c’ were formed, which, by derivatization with 2-chlorobenzoyl chloride 14, led to the crystalline products 15 and 15’. Their structures were established by X-ray crystallography. From the reaction of 8 and ethyl diazoacetate (1d), the opposite regioisomer 13 was formed. The monosubstituted thioamide 16 reacted with 1a to give the unstable 4,5-dihydro-1H-pyrazole-3-carbothioamide 17