937 research outputs found
Influence of Nutrient Source on Yield, Quality and Economics of Seed Production in Vegetable Cowpea (Vigna unguiculata ssp. sesquipedalis)
Field investigation was carried out to study the influence of different sources of nutrients on seed production in vegetable cowpea (Vigna unguiculata ssp. sesquipedalis) during 2010-11 in Randomized Block Design, with twelve combinations of nutrient sources. Results showed significant variation in seed yield potential in the crop. Highest seed yield (435.97kg ha-1) was recorded in the treatment where recommended NPK dose for the seed crop was applied along with vermicompost at 50 per cent nitrogen substitution. Yield attributes were found non-significant, but had a positive influence on seed yield. Germination percentage and 100-seed weight was significantly higher in treatments receiving a combination of vermicompost and poultry manure. Benefit:Cost analysis revealed that 50 per cent N substitution with vermicompost and 25% N with poultry manure were the most profitable in cowpea seed production
A4_2 Flipping Vehicles
Vehicles sometimes roll over when driving. We investigated whether this was due only to excessive speeding or if other factors were at play. By creating a model comparing bend radius, velocity and angle to the vehicle's centre of mass, we concluded that in most cases other factors relating to the road surface would be involved
A4_5 Solar Propelled Rocket
In this paper we discuss whether it would be feasible to replace the current Soyuz rocket’s Earth launch phase, with the radiation pressure from reflected solar radiation. We find that the mirror would need an area 2.05 × 105 km^2 in an ideal situation. This is deemed too large to be practical
RNA silencing in plants: Flash report!
Earlier this year plant scientists met in Santa Fe, New Mexico at the Keystone Symposium "RNA Silencing Mechanisms in Plants". Sessions included small RNA biogenesis and signalling, development and stress responses, small RNA-directed DNA methylation, and interaction with pathogens. This report highlights some of the prominent and recurring themes at the meeting and emerging arenas of future research.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
The goldilocks placebo effect:Placebo effects are stronger when people select a treatment from an optimal number of choices
People are often more satisfied with a choice (e.g., chocolates, pens) when the number of options in the choice set is "just right" (e.g., 10-12), neither too few (e.g., 2-4) nor too many (e.g., 30-40). We investigated this "Goldilocks effect" in the context of a placebo treatment. Participants reporting nonspecific complaints (e.g., headaches) chose one of Bach's 38 Flower Essences from a choice set of 2 (low choice), 12 (optimal choice), or 38 (full choice) options to use for a 2-week period. Replicating earlier findings in the novel context of a health-related choice, participants were initially more satisfied with the essence they selected when presented with 12 versus either 2 or 38 options. More importantly, self-reported symptoms were significantly lower 2 weeks later in the optimal (12) versus nonoptimal choice conditions (2 and 38). Because there is no known active ingredient in Bach's Flower Essences, we refer to this as the Goldilocks placebo effect. Supporting a counterfactual thinking account of the Goldilocks effect, and despite significantly fewer symptoms after 2 weeks, those in the optimal choice set condition were no longer significantly more satisfied with their choice at the end of testing. Implications for medical practice, especially patient choice, are discussed.</p
Protoplast fusion studies in Ocimum species
Protoplasts of three Ocimum species, viz., O. basilicum, O. sanctum and O. gratissimum derived from leaf samples were used for studying fusion. The isolation of protoplasts were carried out using 1 % cellulase and 0.5 % pectinase in combination with Cocking-Peberdy-White (CPW)–13% mannitol solution as it gave the best results. The protoplasts obtained by enzymatic digestion were purified by centrifugation. The yield of protoplasts was found to be highest when centrifuged at 800 rpm for 15 minutes at 4ºC. Among the fusogen combinations tried to obtain homokaryons, 40 % Polyethylene glycol (PEG)-6000 fusogen solution gave better results when compared to the other combinations. The Ca2+ concentration and pH level (5-9) were altered and studied but major changes in time taken for fusion were not observed. The mean count of protoplasts per ml was found to be 209,200 for O. basilicum, 317,500 for O. gratissimum and 502,500 for O. sanctum. The Evans blue staining test showed that the average percentage of viable cells was 52.8 % for O. basilicum, 52.54 % for O. sanctum and 47.15 % for O. gratissimum
The excess choice effect:The role of outcome valence and counterfactual thinking
Contrary to economic theory, psychological research has demonstrated increased choice can undermine satisfaction. When and why this 'excess choice effect' (ECE) occurs remains unclear. Building on theories of counterfactual thinking we argue the ECE is more likely to occur when people experience counterfactual thought or emotion and that a key trigger is a negative versus positive task outcome. Participants either selected a drink (Experiment 1) or chocolate (Experiment 2) from a limited (6) versus extensive (24) selection (Experiment 1) or were given no choice versus extensive (24) choice (Experiment 2). In both experiments, however, the choice was illusory: Half the participants tasted a 'good' flavour, half a 'bad' flavour. As predicted, extensive choice was only detrimental to satisfaction when participants tasted the 'bad' drink or chocolate, and this was mediated by the experience of counterfactual thought (Experiment 1) or emotion (Experiment 2). When outcomes were positive, participants were similarly satisfied with limited versus extensive and no choice versus extensive choice. Implications for our theoretical understanding of the ECE and for the construction of choice architectures aimed at promoting individual satisfaction and well-being are discussed.16 page(s
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Imaging energy status in live cells with a fluorescent biosensor of the intracellular ATP-to-ADP ratio
The ATP:ADP ratio is a critical parameter of cellular energy status that regulates many metabolic activities. Here we report an optimized genetically-encoded fluorescent biosensor, PercevalHR, that senses the ATP:ADP ratio. PercevalHR is tuned to the range of intracellular ATP:ADP expected in mammalian cells, and it can be used with one- or two-photon microscopy in live samples. We use PercevalHR to visualize activity-dependent changes in ATP:ADP when neurons are exposed to multiple stimuli, demonstrating that it is a sensitive reporter of physiological changes in energy consumption and production. We also use PercevalHR to visualize intracellular ATP:ADP while simultaneously recording currents from ATP-sensitive potassium (KATP) channels in single cells, showing that PercevalHR enables the study of coordinated variation in ATP:ADP and KATP channel open probability in intact cells. With its ability to monitor changes in cellular energetics within seconds, PercevalHR should be a versatile tool for metabolic research
Exploring the role of normative, financial and environmental information in promoting uptake of energy efficient technologies
The potential of normative and feedback (financial vs. environmental) information in guiding pro-environmental decision-making behaviour was explored in a 2 × 2 (plus control) choice experiment. Using the context of home heating, 599 non-student participants from the UK general public were asked to choose between a standard heating system (a gas boiler) and a relatively more-energy efficient option (a heat pump). In line with evidence for the energy efficiency gap for sustainable innovations, there was low uptake of the heat pump (32.5%) in the control condition where no frame information was provided. Yet, in both conditions where normative information was provided, respondents were significantly more likely (vs. control) to choose the heat pump (financial + norm OR 3.63; 95% CIs 2.13,6.19; environmental + norm OR 3.09; 95% CIs 1.67,4.79), advancing understanding of normative social influence in the context of pro-environmental purchase behaviour. When normative information was not provided, only financial (OR 2.82; 95% CIs 1.67,4.79) but not environmental (OR 1.33; 95% CIs 0.78,2.26), feedback was associated with a significantly greater likelihood of heat pump choice. The main effect of normative information was replicated for behavioural intentions (though only for homeowners), but there was no norm-feedback interaction (regardless of homeownership). The implications for researchers looking to promote ‘green’ choice in the context of new technology adoption are discussed.</p
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