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We have examined the adsorption behavior at ∼110 K of NO on NiO(111) overlayers prepared on a Ni(111) substrate. High-resolution electron-energy-loss spectroscopy shows fundamental changes in the vibrational spectrum for the beam dosed surface in comparison with the background dosed surface. Three vibrational peaks are observed after beam dosing, two of which are not observed after conventional background dosing. The peaks can be assigned to NO stretches for a previously observed NO state, a new NO bonding geometry, and a new NO2 surface species, previously unobserved under NO dosing. The difference is accounted for by increased NO uptake due both to kinetically activated adsorption and to increased exposure. [ABSTRACT FROM AUTHOR]

Cyperus rotundus (purple nutsedge) is considered one of the most noxious weeds affecting agricultural areas worldwide. With its fast growth rate, it competes with annual crops for water, minerals, light and space. It excretes allelopathic materials that impede crop development. Controlling this weed is difficult and is done mostly by manual weeding, cultivation and herbicides, with limited effectiveness. A method was developed for the control of C. rotundus. A machine penetrates the soil and rearranges it, so that the tubers are lifted to the upper soil layer, where they are left exposed to the hot summer climate, dehydrate and die. The method was tested in seven field experiments on various soil types. Two months after the experimental plots were irrigated, 70-100% weed control was observed. The machine's speed (at 1.2 or 1.8 km h−1) and the number of treatments (one, or two treatments a month apart) did not influence the level of weed control. The method has a very high potential to replace manual weeding and application of herbicides. Further work will test whether the treatment has a long-term effect or should be repeated every season. [ABSTRACT FROM AUTHOR]

A 3DOF mobile Cartesian robotic harvester for two-dimensionally distributed crops such as melons is being developed. A two-step procedure to calculate the trajectory of its manipulator that will result in the maximum number of melons harvested is described in this article. The goal of the first step is to calculate the minimum-time trajectory required to traverse between any two melons while adhering to velocity, acceleration, location, and endpoint constraints. This step is accomplished in a hierarchal manner by solving several subproblems involving optimal control and nonconvex optimization, enabling optimal (maximum) melon harvesting to be formulated as an orienteering problem with time windows. In the second step, the orienteering problem is solved using the moving branch and prune method, based on dynamic programming. This enables suboptimal sequences of melons (out of all options) to be eliminated on the fly without the need to solve the entire problem at once. An example is shown to demonstrate the efficacy of the algorithm. [ABSTRACT FROM AUTHOR]

In warm-winter regions, where early ripening of table grapes is enabled by the climate, prolonged dormancy is a major delaying obstacle to early-season marketing. Successful production in these regions depends on chemically or physically overcoming the dormancy cycle to compensate for lack of natural chilling. It was previously shown that heat shock from hot air at 150°C induces dormancy release of detached grapevine buds under a controlled environment. In the present study, a heat-shock generator (HSG) for enhancement of dormancy release of whole vines was developed and tested under field conditions. The HSG heats a partially-enclosed volume of air to a required temperature and conveys it through the vines at a speed that results in the desired exposure duration. Heat shocks of 150°C for 15 and 30 s applied in situ to dormant cv. Muscat of Alexandria vines induced earlier dormancy release and significantly greater yield (156%) relative to the control. A longer heat shock of 90 s negatively affected the dormancy release. The HSG is similar to other common agricultural practices in operational simplicity, and its cost and environmental benefits make it a viable alternative to chemical application. [ABSTRACT FROM AUTHOR]

Groups of common carp (Cyprinus carpio) were trained for 33 days to discriminate between two acoustic signals differing in frequency and temporal pattern. One signal (positive stimulus) was reinforced by food, while the other (negative stimulus) was not rewarded. When exposed to 3 positive and 3 negative stimuli per day (training Paradigm 1) the fish responded similarly to the two signals. When daily negative stimuli outnumbered positive stimuli (3 positive and 33 negative, training Paradigm 2) the fish responded similarly to the two signals for the first 2 weeks and then began to discriminate between them. Discriminatory response was statistically significant from Day 21 of training. After 33 days, training was switched from Paradigm 2 to Paradigm 1 and the fish maintained their discriminatory capability. The results are interpreted in terms of anticipatory frustration and risk management., (Copyright (c) 2010 Elsevier B.V. All rights reserved.)