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Wind energy has developed worldwide, becoming a mature technology. Nevertheless, major advances regarding wind turbine aerodynamics and control as well as wind farm control and its integration in the power grid are being foreseen in the near future. To accomplish that, different simulation tools have emerged. The Actuator Line Model (ALM) in the frame of Large Eddy Simulation method has been used to study different related topics, from wake stability to wind turbine interaction and wind farm control, and it is considered the state of the art to simulate with high fidelity the wind flow through wind turbines and wind farms. Despite that, the ALM results, particularly loads and power production, have shown to be dependent on the numerical setup, like the projection function and its smearing parameter. The present paper aims to contribute to the latter by showing the influence of limiting the projection region. It is found that projecting the aerodynamic forces onto a cylinder that confines the rotor disk improves the computed power and loads compared to a Blade Element Momentum code and affects the wake development.

This paper describes a simple design for increasing the tolerance of reagent dislocation on a paper-based platform using a combination of wax-treated paper and a vortex mixer. To date, massive budgetary funds are required in the biotechnological industry to develop new applications; a large part of that cost is attributable to the screening of specific chemical compounds. Here, we propose using a liquid-handling robot to automatically deposit selected reagents on a paper-based platform. We also present a preliminary concept approach for developing a reagent placing device with simple and inexpensive features. A defect of inaccuracy was observed between droplet location and test well location after viewing the performance of the liquid-handling robot on our paper-based platform. Because of dislocation error resulting from robotic reagent placement, we decided to apply an external, rotational force following droplet placement in order to compensate for the distance of reagent dislocation. Note, the largest distance of reagent dislocation was determined by examining the results of altering applied reagent volume, but not concentration, in volumes from 5 µL to 30 µL in a series of experiments. As a result of these experiments, we observed that dislocation was positively affected by an increase in applied volume. A colorimetric assay for nitrite detection was also performed to confirm the feasibility of this method. This work, we believe, can minimize the cost of chemical compound screening for the biotechnological industry.

Background: Spasticity is defined/assessed in resting limbs, where increased stretch reflex activity and mechanical joint resistance are evident. Treatment with antispastic agents assumes that these features contribute to the movement disorder, although it is unclear whether they persist during voluntary contraction. Objectives: To compare reflex amplitude and joint resistance in spastic and normal limbs over an equivalent range of background contraction. Methods: Thirteen normal and eight hemiparetic subjects with mild/moderate spasticity and without significant contracture were studied. Reflex and passive joint resistance were compared at rest and during six small increments of biceps voluntary contraction, up to 15% of normal maximum. A novel approach was used to match contraction levels between groups. Results: Reflex amplitude and joint mechanical resistance were linearly related to contraction in both groups. The slopes of these relations were not above normal in the spastic subjects on linear regression. Thus, reflex amplitude and joint resistance were not different between groups over a comparable range of contraction levels. Spastic subjects exhibited a smaller range of reflex modulation than normals because of decreased maximal contraction levels (weakness) and significant increases of resting contraction levels. Conclusions: Spasticity was most evident at rest because subjects could not reduce background contraction to normal. When background contractions were matched to normal levels, no evidence of exaggerated reflex activity or mechanical resistance was found. Instead, reduced capacity to modulate reflex activity dynamically over the normal range may contribute to the movement disorder. This finding does not support the routine use of antispastic agents to treat the movement disorder.