1,375 research outputs found
“Four machines for sod-seeding in comparison: first results of operational and technical tests in Basilicata”
Our study was carried out to evaluate four different seeders for sod-seeding by a qualitative and quantitative comparison of their performances on cereal crops in Basilicata.
The application of sod-seeding, alias no tillage, it may represent a valid alternative to traditional seeding in areas with high cereal vocation, as a guarantee against production costs, safeguarding the productive and environmentalists aspects in the south of Italy, where there is a great crop specialization and higher environmental risk resulting from intensive farming operations.
So, were organized tests with four different seeders: Gaspardo-Directa, Amazone AD 300, Alpego ASI 303 and Laseminasodo.
We analysed the technical and operational characteristics of the seeders, the distribution regularity of the seed and the parameters concerning the harvesting.
Relating to this study, the most important difference, between these machines we considered, was the coulter body. The results were interesting for all machines, the operational capabilities have been certified on values equal to 1,8 ha/h, satisfactory values regularity of longitudinal and transverse distribution of the seed considering that the value of plants emergency was close to 90%. About yield obtained, some data collected showed a higher value compared with that obtained with the traditional seeding in the same soil conditions
An intrusion and fault tolerant forensic storage for a SIEM system
Current Security Information and Events Management (SIEM) solutions lack a data storage facility which is secure enough - i.e. stored events related to security incidents cannot be forged and are always available - that it can be used for forensic purposes. Forensic storage used by current SIEM solutions uses traditional RSA algorithm to sign the security events. In this paper we have analyzed the limits of current forensic storages, and we have proposed an architecture for forensic storage, implementing a threshold-based variant of the RSA algorithm, that outperforms state of the art SIEM solutions in terms of intrusion- and fault-tolerance. We show by experiments that our forensic storage works correctly even in the presence of cyber-attacks, although with a performance penalty. We also conduct an experimental campaign to evaluate the performance cost of the proposed scheme as a function of the threshold
A new data analysis framework for the search of continuous gravitational wave signals
Continuous gravitational wave signals, like those expected by asymmetric
spinning neutron stars, are among the most promising targets for LIGO and Virgo
detectors. The development of fast and robust data analysis methods is crucial
to increase the chances of a detection. We have developed a new and flexible
general data analysis framework for the search of this kind of signals, which
allows to reduce the computational cost of the analysis by about two orders of
magnitude with respect to current procedures. This can correspond, at fixed
computing cost, to a sensitivity gain of up to 10%-20%, depending on the search
parameter space. Some possible applications are discussed, with a particular
focus on a directed search for sources in the Galactic center. Validation
through the injection of artificial signals in the data of Advanced LIGO first
observational science run is also shown.Comment: 21 pages, 8 figure
An improved algorithm for narrow-band searches of continuous gravitational waves
Continuous gravitational waves signals, emitted by asymmetric spinning
neutron stars, are among the main targets of current detectors like Advanced
LIGO and Virgo. In the case of sources, like pulsars, which rotational
parameters are measured through electromagnetic observations, typical searches
assume that the gravitational wave frequency is at a given known fixed ratio
with respect to the star rotational frequency. For instance, for a neutron star
rotating around one of its principal axis of inertia the gravitational signal
frequency would be exactly two times the rotational frequency of the star. It
is possible, however, that this assumption is wrong. This is why search
algorithms able to take into account a possible small mismatch between the
gravitational waves frequency and the frequency inferred from electromagnetic
observations have been developed. In this paper we present an improved pipeline
to perform such narrow-band searches for continuous gravitational waves from
neutron stars, about three orders of magnitude faster than previous
implementations. The algorithm that we have developed is based on the {\it
5-vectors} framework and is able to perform a fully coherent search over a
frequency band of width (Hertz) and for hundreds of spin-down
values running a few hours on a standard workstation. This new algorithm opens
the possibility of long coherence time searches for objects which rotational
parameters are highly uncertain.Comment: 19 pages, 8 figures, 6 tables, submitted to CQ
Fosamprenavir treatment in a highly active antiretroviral therapy schedule induces a HCV-RNA decrease and a Th1 network boost in HIV/HCV-coinfected patients
AbstractHIV/HCV co-infected naïve patients (four females and six males) were evaluated for their response to the following treatment schedule: [(AZT 300 mg + 3TC 300 mg twice daily) + (fosamprenavir 700 mg twice daily) + (RTV 100 mg)]. CD3+/CD4+ T cells, interferon-γ (INF-γ) and interleukin-4 (IL-4) HCV-specific response, viral loads and transaminase levels were evaluated at time 0, and after 1, 3 and 6 months of therapy (T0, T1, T3, and T6 respectively). HIV-RNA, HCV-RNA and transaminases decreased at T1 and T3 compared with T0 (Mann–Whitney p <0.001, p <0.01 and p <0.01, respectively). At all time points, CD4+ and HCV-specific INF-γ responses were higher (p <0.001; p <0.001), and IL-4 lower (p <0.01) after treatment. At T6, HCV-RNA was only negative in four out of ten patients whereas all had normal transaminase levels. These findings indicate that HAART treatment including fosamprenavir is able to activate a Th1 network in HIV/HCV co-infected patients. Moreover, these results, to be confirmed by larger cohort follow-up studies, suggest that this protease inhibitor could have potential implications for the treatment of chronic hepatitis C in HIV–positive patients
Quantitative models of hydrothermal fluid–mineral reaction:The Ischia case
The intricate pathways of fluid–mineral reactions occurring underneath active hydrothermal systems are explored in this study by applying reaction path modelling to the Ischia case study. Ischia Island, in Southern Italy, hosts a well-developed and structurally complex hydrothermal system which, because of its heterogeneity in chemical and physical properties, is an ideal test sites for evaluating potentialities/limitations of quantitative geochemical models of hydrothermal reactions. We used the
EQ3/6 software package, version 7.2b, to model reaction of infiltrating waters (mixtures of meteoric water and seawater in variable proportions) with Ischia’s reservoir rocks (the Mount Epomeo Green Tuff units; MEGT). The mineral assemblage and composition of such MEGT units were initially characterised by ad hoc designed optical microscopy and electron microprobe analysis, showing that phenocrysts (dominantly alkali–feldspars and plagioclase) are set in a pervasively altered (with abundant clay minerals and zeolites) groundmass. Reaction of infiltrating waters with MEGT minerals was simulated over a
range of realistic (for Ischia) temperatures (95–260° C) and CO2 fugacities (10 ^-0.2 to 10^0.5) bar. During the model runs, a set of secondary minerals (selected based on independent information from alteration minerals’ studies) was allowed to precipitate from model solutions, when saturation was achieved. The compositional evolution of model solutions obtained in the 95–260°C runs were finally compared with compositions of Ischia’s thermal groundwaters, demonstrating an overall agreement.
Our simulations, in particular, well reproduce the Mg-depleting maturation path of hydrothermal solutions, and have end-of-run model solutions whose Na–K–Mg compositions well reflect attainment of full-equilibrium conditions at run temperature.
High-temperature (180–260° C) model runs are those best matching the Na–K–Mg compositions of Ischia’s most chemically
mature water samples, supporting quenching of deep-reservoir conditions for these surface manifestations; whilst Fe, SiO2 and, to a lesser extent, SO4 contents of natural samples are better reproduced in low-temperature (95°C) runs, suggesting that these species reflect conditions of water–rock interaction in the shallow hydrothermal environment. The ability of model runs to reproduce the compositional features of Ischia’s thermal manifestations, demonstrated here, adds supplementary confidence
on reaction path modelling as a realistic and insightful representation of mineral–fluid hydrothermal reactions. Our results, in particular, demonstrate the significant impact of host rock minerals’ assemblage in governing the paths and trends of hydrothermal fluids’ maturation
Performance assessment of a distributed intrusion detection system in a real network scenario
The heterogeneity and complexity of modern networks and services urge the requirement for flexible and scalable security systems, which can be dynamically configured to suit the everchanging nature of security threats and user behavior patterns. In this paper we present a distributed architecture for an Intrusion Detection System, allowing for traffic analysis at different granularity levels, performed by using the best available techniques. Such architecture leverages the principle of separation of concerns, and hence proposes to build up a system comprising entities specialized in performing different tasks, appropriately orchestrated by a broker entity playing the crucial role of the mediator. This paper stresses the point that a distributed system, besides being inherently more scalable than a centralized one, allows for better detection capabilities thanks to the effective exploitation of the inner heterogeneity of the involved detection engines. In order to support our findings, we will describe the design, implementation and deployment of the proposed solution in the framework of the INTERSECTION FP7 European Project
A resilient architecture for forensic storage of events in critical infrastructures
In Critical Infrastructures, forensic analysis of stored events is an essential task when a security breach occurs. The goal of forensic analysis is to provide evidence to be used as valid proofs in a legal proceeding. So, it is very important to ensure the integrity of the events stored in order to perform a correct forensic analysis. Today, most of the SIEMs used to protect the Critical Infrastructures sign the security events with RSA classic algorithm in order to ensure their integrity. The signed security events cannot be admissible as evidence if the secret key is compromised, or when the module responsible for signing operations is down for any reason. In this paper a new architecture that overcomes these limitations has been proposed. Experimental tests show the performance of our architecture and the high resilience in faulty situations, i.e. some nodes are under attack
Functional properties of edible insects: a systematic review
: Consumption of edible insects has been widely suggested as an environmentally sustainable substitute for meat to reduce GHG emissions. However, the novel research field for edible insects rely on the content of bioactive ingredients and on the ability to induce a functional effect in humans. The goal of this manuscript was to review the available body of evidence on the properties of edible insects in modulating oxidative and inflammatory stress, platelet aggregation, lipid and glucose metabolism and weight control. A search for literature investigating the functional role of edible insects was carried out in the PUBMED database using specific keywords. A total of 55 studies, meeting inclusion criteria after screening, were divided on the basis of the experimental approach: in vitro studies, cellular models/ex vivo studies or in vivo studies. In the majority of the studies, insects demonstrated the ability to reduce oxidative stress, modulate antioxidant status, restore the impaired activity of antioxidant enzymes and reduce markers of oxidative damage. Edible insects displayed anti-inflammatory activity reducing cytokines and modulating specific transcription factors. Results from animal studies suggest that edible insects can modulate lipid and glucose metabolism. The limited number of studies focused on the assessment of anticoagulation activity of edible insects make it difficult to draw conclusions. More evidence from dietary intervention studies in humans is needed to support the promising evidence from in vitro and animal models about the functional role of edible insects consumption
A semi-coherent analysis method to search for continuous gravitational waves emitted by ultra-light boson clouds around spinning black holes
As a consequence of superradiant instability induced in Kerr black holes,
ultra-light boson clouds can be a source of persistent gravitational waves,
potentially detectable by current and future gravitational-wave detectors.
These signals have been predicted to be nearly monochromatic, with a small
steady frequency increase (spin-up), but given the several assumptions and
simplifications done at theoretical level, it is wise to consider, from the
data analysis point of view, a broader class of gravitational signals in which
the phase (or the frequency) slightly wander in time. Also other types of
sources, e.g. neutron stars in which a torque balance equilibrium exists
between matter accretion and emission of persistent gravitational waves, would
fit in this category. In this paper we present a robust and computationally
cheap analysis pipeline devoted to the search of such kind of signals. We
provide a full characterization of the method, through both a theoretical
sensitivity estimation and through the analysis of syntethic data in which
simulated signals have been injected. The search setup for both all-sky
searches and higher sensitivity directed searches is discussed.Comment: 13 pages, 13 figure
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