174 research outputs found
Green manure and compost effects on n-p dynamics in mediterranean organic stockless systems
Stockless systems, where plant and animal production are uncoupled, represent a common condition in Mediterranean areas. In organic systems, soil fertility is mainly managed by green manures, whereas composts of plant origin represent suitable soil conditioners. The low P content of these materials, together with the shortage of animal waste availability, determine potential nutrient depletion overtime and, in calcareous soils, P mining conditions. In a two-year field experiment in Central Italy, the effect of green manure vetch (Vicia villosa) (GM+) was compared with a control left fallow (GM-), combined with P-based fertilizers (F) on organic maize (Zea mays). Yields and N-P dynamics were evaluated by direct measurements, nutrient balance and efficiency index. N balance was higher than in GM+ GM- (+71.8 and -23.6 kg N ha-1, respectively). P enriched compost with RP (rock-phosphate) (EP), showed significant improvement in P use efficiency (meanly +34%) than other treatments (unfertilized control (RP), not P enriched compost (NEP)) and P equilibrium in the short run. On the other hand, P-fertilizers and maize residues soil incorporation determined P surplus in a long perspective (up to +10 kg P ha-1). Results emphasize the possibility of P reintegration in stockless organic systems without animal wastes
Mulch-based no-tillage effects on weed community and management in an organic vegetable system
Weeds can cooperate with the agroecosystem\u2019s functioning by providing ecosystem services. Effective weed management should mitigate negative weed\u2013crop interference, while maintaining a functional and balanced weed community. In a two-year trial, the in-line/roller crimper (RC) was used to terminate an agroecological service crop (ASC; here barley, Hordeum vulgare L.) before organic zucchini (Cucurbita pepo, L.) and compared with green manure (GM) ASC and tilled no-ASC with Mater-Bi mulch on the rows (No_ASC). Zucchini yield, soil N availability, weed density/cover, biomass, and community composition were assessed. Analysis of variance, exploratory statistical analysis, and non-parametric inferential approaches were run, respectively, on agronomic data, species-specific weed frequencies, and Shannon diversity. Zucchini yield was the highest in No_ASC, due to soil N immobilization under high C:N barley residues in GM and RC. Multivariate analysis discriminated RC from tilled systems, outlining a specific ensemble of weed species correlated to Shannon diversity. From zucchini fruit set, RC selectively favored Polygonum aviculare L. and Helminthotheca echioides (L.), reasonably because of their oligotrophy and creeping habit. Their dominance finally caused low RC weed control. Results highlight strong weed selective pressure by the mulch-based no-tillage. Understanding the mechanisms underpinning the impact of soil management practices on weed community can drive towards a tailor-made and more effective weed management
EFFECTS OF COVER CROP MANAGEMENT AND COMPOST APPLICATION ON SOIL FERTILITY OF ORGANIC MELON
A field experiment was carried out in Central Italy on growing melon (Cucumis melo L.) after barley (Hordeum vulgare L.). Three different systems of cover crop termination (green manure, roller crimper and fallow, as control) were combined with three doses of compost (0, 15 and 30 t ha-1 d.m.) in a strip plot design. The main objective of the research was to evaluate their effects on organic melon production and on short and long term soil nitrogen (N) fertility. Marketable yield and quality and soil N availability along the melon cycle were determined and a simplified N budget calculated. Green manure (GM) treatment showed the highest total and marketable yield, followed by fallow (FA), while roller crimper (RC) was characterized by a significant lower yield respect to the other two treatments (45% and 62% of the marketable yield of GM and FA, respectively). On the other side, long term soil N fertility of GM and FA were characterized by N deficit unless combined with compost application at the dose of 15 t ha-1 d.m
Offloading personal security applications to a secure and trusted network node
The current device-centric protection model against security threats has serious limitations from the final user
perspective, among the other the necessity to keep each device updated with the latest security updates and the necessity to replicate all the security polices across all devices. In our model, the protection is decoupled from the users terminals and it is provided through a Trusted Virtual Domain (TVD) instantiated in future edge routers. Each TVD provides unified and homogeneous security for a single user, irrespective of the terminal employed. This paper shows a first prototype implementing this concept through a network element, called Network Edge Device, capable of running the proposed virtualized architecture and making extensive use of SDN technologies, with the aim at providing a uniform security level for the final user
Agroecological practices and agrobiodiversity. A case study on organic orange in southern Italy
7noopenThe integration of Agroecological Service Crops (ASCs) into agroecosystems can provide several ecological services, such as nutrient cycling and disease and weed management. A two-year experiment on an organic orchard was carried out to compare barley (B) and horse bean (HB) ASCs with a control without ASC (Cont) in combination with fertilizers. Their effects on soil fertility and weed- and soil-borne fungi communities were evaluated by direct measurements, visual estimation, and indicators computation. A Principal Component Analysis (PCA) was used to identify latent patterns and redundancy among variables, whereas a correlation analysis was used to discriminate the compared systems within the PCA matrix. The empirical results of this study put in evidence the correlation among soil, weed, and fungal variables. A slight contribution of fertilizers on the system’s variability was observed, whereas a clear effect of ASCs was highlighted. The systems differed in weed communities, with the lowest density associated to B and the highest to Cont. B showed the highest fungal diversity, with changes in community compared to HB. HB showed a contribution on soil fertility, being associated to organic matter increase and N availability, and evidencing mixed impacts on soil quality and ecosystem functioning. Overall, the above-ground diversity and below-ground community results were inter-correlated.openCiaccia C.; La Torre A.; Ferlito F.; Testani E.; Battaglia V.; Salvati L.; Roccuzzo G.Ciaccia, C.; La Torre, A.; Ferlito, F.; Testani, E.; Battaglia, V.; Salvati, L.; Roccuzzo, G
Techniques for Complex Analysis of Contemporary Data
Contemporary data objects are typically complex, semi-structured, or unstructured at all. Besides, objects are also related to form a network. In such a situation, data analysis requires not only the traditional attribute-based access but also access based on similarity as well as data mining operations. Though tools for such operations do exist, they usually specialise in operation and are available for specialized data structures supported by specific computer system environments. In contrary, advance analyses are obtained by application of several elementary access operations which in turn requires expert knowledge in multiple areas. In this paper, we propose a unification platform for various data analytical operators specified as a general-purpose analytical system ADAMiSS. An extensible data-mining and similarity-based set of operators over a common versatile data structure allow the recursive application of heterogeneous operations, thus allowing the definition of complex analytical processes, necessary to solve the contemporary analytical tasks. As a proof-of-concept, we present results that were obtained by our prototype implementation on two real-world data collections: the Twitter Higg's boson and the Kosarak datasets
Safety Considerations and Proposed Workflow for Laboratory-Scale Chemical Synthesis by Ball Milling
Chemical reactions that take place in a ball mill and in the absence of a bulk reaction solvent present different safety profiles to stirred solution reactions. Herein, we present and describe steps that a researcher may take to better ensure that they have considered some of the hazards and measures that emerge and minimize the risk to themselves and their colleagues
Massive transcriptome sequencing of human spinal cord tissues provides new insights into motor neuron degeneration in als
ALS is a devastating and debilitating human disease characterized by the progressive death of upper and lower motor neurons. Although much effort has been made to elucidate molecular determinants underlying the onset and progression of the disorder, the causes of ALS remain largely unknown. In the present work, we have deeply sequenced whole transcriptome from spinal cord ventral horns of post-mortem ALS human donors affected by the sporadic form of the disease (which comprises ∼90% of the cases but which is less investigated than the inherited form of the disease). We observe 1160 deregulated genes including 18 miRNAs and show that down regulated genes are mainly of neuronal derivation while up regulated genes have glial origin and tend to be involved in neuroinflammation or cell death. Remarkably, we find strong deregulation of SNAP25 and STX1B at both mRNA and protein levels suggesting impaired synaptic function through SNAP25 reduction as a possible cause of calcium elevation and glutamate excitotoxicity. We also note aberrant alternative splicing but not disrupted RNA editing
Underuse of spirometry by general practitioners for the diagnosis of COPD in Italy.
Background. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) underlines that spirometry is the gold standard as the most reproducible, standardised, and objective way of measuring airflow limitation in the diagnosis and assessment of Chronic Obstructive Pulmonary Disease (COPD). However, studies undertaken in different countries have suggested a widespread underuse of spirometry by general practitioners to establish the diagnosis of COPD. Precise estimates of the prevalence of physician-diagnosed COPD in Italy are not currently available. In collaboration with the Italian Academy of General practitioners (SIMG) we have investigated the degree of use of spirometry to establish the diagnosis of COPD in Italy. Methods. A standardised questionnaire has been selfadministered to a sample of 2425 Italian general practitioners (representing 5% of all the Italian doctors involved in general practice). They have been chosen to cover each of the Italian counties. Results. The prevalence of physician-diagnosed COPD was found to be approximately 4%. However, 30% of general practitioners do not use spirometry to establish the diagnosis of COPD. The main reasons given for the failure to use spirometry are (i) that spirometry is not necessary for the diagnosis of COPD or (ii) there are logistical limitations to the access of the patients to lung function laboratories. Conclusions. This data suggests that contrary to GOLD Guidelines, in Italy, as with other countries, spirometry is not always used in the diagnosis of COPD. There is a clear necessity for further education initiatives targeted to this group of physicians
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