The economic sustainability of second crops implementation in organic maize production

Although organic crop production has numerous advantages, concerns about economic sustainability, both environmental and financial, make farmers reluctant to convert their conventional production into the organic production. Certain agricultural methods, such as second crop use, can alleviate some problems regarding soil tilth, erosion prevention, nutrients availability and weed control, thus contributing toward more sustainable crop production. Also, the added value crop growth, such as maize (Zea mais L.) hybrid's parental line production, with lower yields but higher prices, can contribute to sustainability of organic production. In order to test the hypothesis that the use of second crops can contribute toward the sustainability of organically grown maize after soybean (Glycine max L.) as a previous crop in the crop rotation, the experimental site was established in Valpovo, Croatia, in the eutric brown soil type, during the years 2005 and 2006. The experimental design was set up as a CRBD in four repetitions, with six second crop treatments: CT – Control, without second crop; WW – winter wheat (Triticum aestivum L.) second crop; RY – rye (Secale cereale L.) second crop; FP – fodder pea (Pisum arvense L.) second crop; WP – mixture of WW and FP; and RP – mixture of RY and FP. In order to assess the soil surface protection and evaluate the weed suppression, the second crop coverage had been recorded. Regarding the economic sustainability, the second crop use depending costs were analysed in relation to the extra produced maize yield. The RY treatment had the highest profitability, followed by WW, RP and O. The WP and FP revealed lower relative profitability than O, thus presenting the evidence of sustainability risk of these treatments

Effects of the second crop on maize yield and yield components in organic agriculture

The second crop use in organic agriculture is a known method of maintaining the soil tilth, soil protection against environmental deterioration, soil nutrients conservation and even the weed control. The nitrogen conservation from previous leguminose crop is even more important, especially in the organic agriculture where use of N-fertilizers is the strictly forbiden, and second crops can be used as a catch crops for nutrients in rotation prior to the crops with the high N requirement. The choice of the proper second crop has, however, been insufficiently investigated, especially for agri-environmental conditions of the Panonian agricultural area in Croatia. The second crop experiment was established in Valpovo, Croatia, in the eutric brown soil type, during the years 2005 and 2006. The aim of the experiment was to investigate the effects of different second crops and their combinations on maize (Zea mais L.) yield and yield components in organic agriculture after soybean (Glycine max L.) in crop rotation. The experimental design was set up as a CRBD in four repetitions, with soybean as a previous crop in crop rotation. The six second crop treatments were: O – Control, without second crop; WW – winter wheat (Triticum aestivum L.) second crop; RY – rye (Secale cereale L.) second crop; FP – fodder pea (Pisum arvense L.) second crop; WP – mixture of the WW and FP; and RP – mixture of RY and FP. The WW treatment had the highest second crop dry mass, whereas FP had the lowest dry mass. The highest plant density was recorded for FP, and it was higher than the RP plant density, which also had the lowest plant height. The achieved maize yields were the highest for RY, but they were not significanlty different from the O, RP, and WW treatments. However, the yield achieved by RY treatment was significantly higher than the yields recorded for WP and FP treatments. The absolute mass and hectolitre mass did not show any statistical differences among treatments

Autoxidation of lipids in parchment

Historic parchment is a macromolecular material, which is complex due to its natural origin, inhomogeneity of the skin structure, unknown environmental history and potential localised degradation. Most research into its stability has so far focussed on thermal and structural methods of analyses. Using gas chromatographic analysis of the atmosphere surrounding parchment during oxidation, we provide the experimental evidence on the production of volatile aldehydes, which can be the products of lipid autoxidation. Oxidation of parchment with different aldehyde emissions was additionally followed in situ using chemiluminometry and the same techniques were used to evaluate the oxidation of differently delipidised parchment. It was shown that the production of peroxides and the emission of aldehydes from the material decrease with lower lipid content. Building on this evidence, we can conclude that the presence of lipids (either initially present in the skin or resulting from conservation intervention) leads to oxidative degradation of collagen and that the non-destructive analysis of the emission of volatiles could be used as a quick tool for evaluation of parchment stability

Evaluation of additive for reducing gaseous emissions from swine waste

Additives can reduce gaseous emissions from swine waste lagoons and pits.  We have demonstrated for the first time that an additive has the potential to reduce methane emission from an anaerobic swine lagoon.  ManureMax®, a humate product was evaluated for its ability to reduce gas and odor emissions from swine anaerobic lagoon and barn flush-water.  Four treatments, Control (no additive), Low (label dosage), Medium (50% higher than label dosage), and High (200% higher than label dosage) were applied to inclined pipes installed in a swine lagoon.  While the Medium and High treatments were not effective, the Low treatment reduced methane, 2-butanone, and tetrahydrofuran concentrations by 34%, 44%, and 57%, respectively vs. the Control in the pipe headspace.  Surface treatment was effective on methane for four weeks.  ManureMax® was ineffective in reducing nitrous oxide and carbon dioxide concentrations in the headspace.  It is unclear why only the Low treatment reduced concentrations of these gases in the lagoon though at least one study also reported similar findings with additive dosage.  The Low treatment reduced chemical oxygen demand and total phosphorus in the lagoon supernatant probably due to chelation, flocculation, and/or oxidation.  Applying treatments to pipes installed in a lagoon could be cost-effective way to compare treatments in replicated, mesocosm-scale studies in a lagoon.  In the lab, all ManureMax® treatments reduced accumulation of three short-chain volatile fatty acids (VFAs) in the headspace of incubated glass bottles but only the High treatment reduced toluene accumulation (by 26%).  The ability of ManureMax® to degrade long- and branch-chain VFAs requires further evaluation and its odor reduction potential should be tested using olfactometry.  Keywords: hog, mesocosm-scale, methane, 2-butanone, tetrahydrofuran, volatile fatty acids, toluene 

Heats of Immersion of Uranium Oxides in n-Nitropropane III.

Heats of wetting· of uranium oxides with different O / U ratios were measured in n-nitropropane and these heats were found to decrease with increasing oxygen content of the oxide\u27s. This behaviour was compared with the opposite t endency in water. It was concluded that a definite amount of U03 is relatively easily formed on the surface of U02 at lower temperatures

How do Wireless Chains Behave? The Impact of MAC Interactions

In a Multi-hop Wireless Networks (MHWN), packets are routed between source and destination using a chain of intermediate nodes; chains are a fundamental communication structure in MHWNs whose behavior must be understood to enable building effective protocols. The behavior of chains is determined by a number of complex and interdependent processes that arise as the sources of different chain hops compete to transmit their packets on the shared medium. In this paper, we show that MAC level interactions play the primary role in determining the behavior of chains. We evaluate the types of chains that occur based on the MAC interactions between different links using realistic propagation and packet forwarding models. We discover that the presence of destructive interactions, due to different forms of hidden terminals, does not impact the throughput of an isolated chain significantly. However, due to the increased number of retransmissions required, the amount of bandwidth consumed is significantly higher in chains exhibiting destructive interactions, substantially influencing the overall network performance. These results are validated by testbed experiments. We finally study how different types of chains interfere with each other and discover that well behaved chains in terms of self-interference are more resilient to interference from other chains

NEW TRIASSIC ASTEROIDEA (ECHINODERMATA) SPECIMENS AND THEIR EVOLUTIONARY SIGNIFICANCE

The Paleozoic-Mesozoic transition saw the disappearance of asteroid stem groups and the ascent of the crown group, but late Paleozoic and Triassic asteroids are rare and transition events are poorly documented. Three new Middle and Late Triassic specimens augment existing data; included are a specimen of Trichasteropsis weissmanni from Germany, a specimen of Trichasteropsis? sp. indet. from Italy, and a possible member of the extant Poraniidae from Slovenia. Presence of a small ossicle at the interbrachial midline and adjacent to the marginal series of the new T. weissmanni specimen is consistent with similar expressions not only of other trichasteropsids but also occurrence of two interbrachial ossicles in Paleozoic, stem-group asterozoans; presence is in turn consistent with a hypothesis of derivation of the axillary/odontophore coupling from two ossicles rather than direct derivation of the crown-group odontophore from a single stem-group axillary. Morphology of Trichasteropsis? sp. indet., including, for example, the evenly-tapering arms are reminiscent of those of diverse crown-group asteroids whereas the enlarged distal arms of T. weissmanni are unique, the morphology of T? sp. indet. thereby potentially indicative of a plesiomorphic, stemward positioning within the Trichasteropsiidae. The range of the Poraniidae is tentatively extended to the Carnian. Similarities shared by the Poraniidae and the Trichasteropsiidae suggest stemward positioning within crown-group diversification; however, known Triassic fossils do not appear closely related to extant taxa identified in recent molecular studies as basal within the crown-group. A temperate climate is suggested as preferred by the Triassic asteroids rather than a tropical, warmer one

Enhancing Dancing: Examining The Potency Of A Combined Action Observation And Brain Stimulation Intervention

Research supports the idea that action observation (AO)-based training can be an effective component of physical training and rehabilitation. While much is known about the benefits of AO for simple movements, less is known about the utility of AO-based training for complex, whole-body sequences of movements. Additionally, positive motor performance and neurophysiological findings are associated with anodal-transcranial direct current stimulation (A-tDCS). Therefore, it may be valuable to investigate the combination of these two approaches to further enhance motor learning. It is unknown how this combination, utilizing an alternative electrode arrangement of t-DCS (bihemispheric anodal corticomotor tDCS [BAC-tDCS]), would affect learning of a complex, whole-body task. The first aim of this dissertation was to assess the replicability/reliability of dance sequence performance scoring using the X-box One KinectTM game Dance Central Spotlight. In Study 1, test-retest reliability was assessed as participants completed three thirty-second trials of repetitive arm flapping in synchrony with a metronome. The results revealed a good to excellent degree of test-retest reliability demonstrating that Dance Central Spotlight could be used as a primary measurement tool for future studies to obtain reliable measures for complex, whole-body motor tasks such as dance. The purpose of the second study was to determine whether AO prior to action execution would improve an individual’s performance on a complex, whole-body task (i.e., dance). In Study 2, participants observed one dance before performing both dances (DANCEA and DANCEB) in a post-test. Participants returned after a washout period (M = 5.40 weeks, SD = 1.42) to observe the opposite dance and complete another post-test. Performance scores were significantly better when individuals had viewed the dance sequence prior to execution compared to when they had not observed the sequence prior to execution. This outcome was observed for DANCEA, which was perceived to be more difficult, but not for DANCEB. The third aim was to examine the relationship between motor learning and a combined non-invasive brain stimulation/AO-based intervention with a complex, whole-body motor skill. Additionally, this study attempted to test the hypothesis that prior physical activity, as assessed by the International Physical Activity Questionnaire (IPAQ), alters the modulatory effects of this combined treatment. In a counterbalanced, cross-over design, participants received either BAC-tDCS or sham during observation of a chosen dance. After a washout period (M = 5.09 weeks, SD = 1.72), participants received the opposite intervention during observation of the dance. Participants performed the dance for Immediate and 1 Week Post-tests. Performance scores were better at 1 Week Post-test than Immediate Post-test, but performance scores did not differ between AO/BAC-tDCS and AO/Sham. There was a moderate, positive correlation between physical activity and overall improvement in dance performance scores after AO/Sham but not AO/BAC-tDCS. An interaction effect was seen between time (Immediate Post-test and 1 Week Post-test) and order in which participants received the intervention (AO/BAC-tDCS and AO/Sham). This investigation indicated that AO may be able to improve learning of a relatively difficult complex, whole-body sequence of movements. Furthermore, it is feasible to combine an AO-based learning intervention with BAC-tDCS, but further research must be done to assess the effectiveness as an order or learning effect may have clouded these results. Lastly, prior physical activity levels should be considered in individuals as it is unclear how one’s history of physical activity may affect their rate of motor learning