Impact of foliar diseases in organically grown barley: Influence of fertilization, nutrient content in leaves, varietal disease resistance characteristics and yield potential

Significant increase in severity of powdery mildew,leaf rust and net blotch with increasing N-content in plant leaves 30 days after germination (all years where the relevant diseases were present at a substantial level). This may explain: · Most of the environmental main effects (field) on disease. · Effect of treatments, i.e., treament 4 resulted in reduced N/increased K content in leaves, which coincided with reduced levels of disease. We observed no clear effect of P, Ca, S, and Zn content in leaves on disease. Micronutrients as Cu, Mo and Mn showed significant effects on powdery mildew in one year but not the other; further interpretation may not be possible due to inter-correlation among the effect of micro-nutrients. The diseases had a significant yield reducing effect, in particular powdery mildew and net blotch, which occurred at highest severities. In addition, net blotch affected root development, resulting in significant shorter roots, whereas powdery mildew did not. The effect of disease on root length was of the same order of magnitude as the factor 'variety', but larger than effects of 'year'

Use of a goal setting intervention to increase adherence to low back pain rehabilitation: A randomized controlled trial

Objective: To examine the effects of a goal setting intervention on self efficacy, treatment efficacy, adherence and treatment outcome in patients undergoing low back pain rehabilitation. Design: A mixed-model 2 (Time) x 3 (Group) randomized controlled trial. Setting: A residential rehabilitation centre for military personnel. Subjects: UK military personnel volunteers (N=48); mean age was 32.9 (SD 7.9) with a diagnosis of non-specific low back pain. Interventions: Subjects were randomly assigned to either a goal setting experimental group (Exp, n=16), therapist-led exercise therapy group (C1, n=16), or non-therapist-led exercise therapy group (C2, n=16). Treatment duration for all groups was 3 weeks. Main measures: Self-efficacy, treatment efficacy and treatment outcome were recorded before and after the treatment period. Adherence was rated during regularly scheduled treatment sessions using the Sports Injury Rehabilitation Adherence Scale (SIRAS). The Biering-Sørensen test was used as the primary measure of treatment outcome. Results: ANCOVA results showed that adherence scores were significantly higher in the experimental group (13.70 ± 1.58) compared with C2 (11.74 ± 1.35), (P<0.025). There was no significant difference for adherence between the experimental group and C1 (P=0.13). Self-efficacy was significantly higher in the experimental group compared to both C1 and C2 (P<0.05), whereas no significant difference was found for treatment efficacy. Treatment outcome did not differ significantly between the experimental and two control groups. Conclusions: The findings provide partial support for the use of goal setting to enhance adherence in clinical rehabilitation

Magic angle spinning (MAS) NMR linewidths in the presence of solid-state dynamics

In solid-state NMR, the magic angle spinning (MAS) technique fails to suppress anisotropic spin interactions fully if reorientational dynamics are present, resulting in a decay of the rotational-echo train in the time-domain signal. We show that a simple analytical model can be used to quantify this linebroadening effect as a function of the MAS frequency, reorientational rate constant, and magnitude of the inhomogeneous anisotropic broadening. We compare this model with other theoretical approaches and with exact computer simulations, and show how it may be used to estimate rate constants from experimental NMR data

Estimating complementarity between education and training

In this paper, we formulate and estimate a structural model of post-schooling training that explicitly allows for possible complementarity between initial schooling levels and returns to training. Precisely, the wage outcome equation depends on accumulated schooling and on the incidence of training. The effect of training on wage growth depends on individual permanent endowments as well as on education. We find evidence of statistically significant complementarity, i.e. the higher educated receive the highest return to the MBA-type training considered here.Skill Complementarity ; Dynamic Treatment Effects ; Dynamic Programming ; Random Coefficients

Sensory quality of organic milk based on grazing and high ratio of legumes in the feeding ration

Organic milk forms an important segment of the fresh milk production in Denmark. However, studies are needed to substantiate the high quality and future development of new variations of organic milk for different consumers. Differences in the composition of organically and conventionally produced milk (free fatty acids and a higher content of antioxidants in organic milk) are suggested to be a result of differences in feeding regimes (maize components in conventional production vs. grass and legumes in organic production). Also, milk from dairy cows fed grass silage has a different flavour compared to milk from dairy cows fed maize silage. This study evaluated the sensory properties of organic milk from dairy cows from different feeding trials. The effect of four different legumes and herbs, lucerne (Medicargo sativa), red clover (Trifolium pratense), white clover (Trifolium repens) and chicory (Cichorium intybus), was studied following a schedule including 4*12 Holstein Frisian cows. Descriptive sensory analysis was performed on the fresh pasteurized unhomogenized full-fat milk (6 replicates in 2 sessions) with a trained panel of 10 assessors. The preliminary results from the descriptive analysis of summer feeding (grazing) and winter feeding (silage) show that feeding with legumes and grass affects the sensory quality of full-fat unhomogenized organic milk. The most distinct milk was obtained from feeding ration high in chicory. This milk was characterized by a bitter and metallic taste and an astringent aftertaste both from the summer grazing and winter silage feeding trials. Red clover was characterized by a boiled milk flavour (summer), lucerne by a fatty aftertaste (winter) and white clover by a sweet and creamy flavour (winter). The results of the first season, which will also include relations between the sensory quality and the milk composition, serve as important inputs for the extensive studies to be conducted during the next three seasons. These studies include farm studies and consumer studies (product information, preference and purchase motives)

Development and critical evaluation of a generic 2-D agro-hydrological model (SMCR_N) for the responses of crop yield and nitrogen composition to nitrogen fertilizer

Models play an important role in optimizing fertilizer use in agriculture to maintain sustainable crop production and to minimize the risk to the environment. In this study, we present a new Simulation Model for Crop Response to Nitrogen fertilizer (SMCR_N). The SMCR_N model, based on the recently developed model EU-Rotate_N for the N-economies of a wide range of crops and cropping systems, includes new modules for the estimation of N in the roots and an associated treatment of the recovery of soil mineral N by crops, for the reduction of growth rates by excessive fertilizer-N, and for the N mineralization from soil organic matter. The validity of the model was tested against the results from 32 multi-level fertilizer experiments on 16 different crop species. For this exercise none of the coefficients or parameters in the model was adjusted to improve the agreement between measurement and simulation. Over the practical range of fertilizer-N levels model predictions were, with few exceptions, in good agreement with measurements of crop dry weight (excluding fibrous roots) and its %N. The model considered that the entire reduction of soil inorganic N during growth was due to the sum of nitrate leaching, retention of N in fibrous roots and N uptake by the rest of the plant. The good agreement between the measured and simulated uptakes suggests that in this arable soil, losses of N from other soil processes were small. At high levels of fertilizer-N yields were dominated by the negative osmotic effect of fertilizer-N and model predictions for some crops were poor. However, the predictions were significantly improved by using a different value for the coefficient defining the osmotic effect for saline sensitive crops. The developed model SMCR_N uses generally readily available inputs, and is more mechanistic than most agronomic models and thus has the potential to be used as a tool for optimizing fertilizer practice

Electron transport through quantum wires and point contacts

We have studied quantum wires using the Green's function technique and the density-functional theory, calculating the electronic structure and the conductance. All the numerics are implemented using the finite-element method with a high-order polynomial basis. For short wires, i.e. quantum point contacts, the zero-bias conductance shows, as a function of the gate voltage and at a finite temperature, a plateau at around 0.7G_0. (G_0 = 2e^2/h is the quantum conductance). The behavior, which is caused in our mean-field model by spontaneous spin polarization in the constriction, is reminiscent of the so-called 0.7-anomaly observed in experiments. In our model the temperature and the wire length affect the conductance-gate voltage curves in the same way as in the measured data.Comment: 8 page