444 research outputs found
Yield and Quality of Sequentially Grown Cherry Tomato and Lettuce under Long-Term Conventional, Low-Input and Organic Soil Management Systems
Besides to conventional fertiliser use, organic and low-input technologies are being increasingly used for soil management in vegetable production. However, different factors operating during crop growth (i.e. the pre-harvest factors) and related to soil properties may affect yield and quality of vegetable crops. The present research aimed to study how different soil management regimes influence soil physical and chemical properties and how these affect yield and some quality traits of two major vegetable crops. We focused on lettuce, a major crop in the area under both conventional and organic production, and on cherry tomato, which is increasingly grown in organic vegetable systems. The soil management systems were: conventional (CM), following recommended fertilisation rates; low input (LI), using minimum fertilisation rates as needed; and organic, including manure application (MA) and incorporation of oat as green manure (GM) and of maize residues (MR). Preliminary results indicate that after 7 years of rotating vegetable crops soil properties tended to improve with some systems: e.g. lower bulk density and higher porosity with MA; higher cation exchange capacity (CEC) with MA and CM. After these 7-year pre-treatments, significant differences in crop growth and yields were observed for cherry tomato and lettuce grown under different production systems, but not for the overall quality indicators. The highest yields of cherry tomato were achieved with CM and MA, due to increased number of fruits per plant, with no differences in fruit weight. Lettuce yields were generally higher with CM compared to LI, although the effect was different for different types of lettuce: the leafy type produced higher yields per area whereas the Latin type produced heavier individual plants. Under organic soil management systems, the relative survival and the visual quality of the Latin type was reduced by Botrytis cinerea infections. The results of the study indicated that plots that underwent long-term applications of 15 t hamanure every two years produced similar yields than conventional systems and had comparable soil fertility attributes. However, the visual quality of the end product may be affected under organic systems. As observed for lettuce, cultivar choice may also play a role, since some lettuce types appeared to be more suitable for such systems than other
EXT-TAURUM P2T: an Extended Secure CAN-FD Architecture for Road Vehicles
The automobile industry is no longer relying on pure mechanical systems; instead, it benefits from advanced Electronic Control Units (ECUs) in order to provide new and complex functionalities in the effort to move toward fully connected cars. However, connected cars provide a dangerous playground for hackers. Vehicles are becoming increasingly vulnerable to cyber attacks as they come equipped with more connected features and control systems. This situation may expose strategic assets in the automotive value chain. In this scenario, the Controller Area Network (CAN) is the most widely used communication protocol in the automotive domain. However, this protocol lacks encryption and authentication. Consequently, any malicious/hijacked node can cause catastrophic accidents and financial loss. Starting from the analysis of the vulnerability connected to the CAN communication protocol in the automotive domain, this paper proposes EXT-TAURUM P2T a new low-cost secure CAN-FD architecture for the automotive domain implementing secure communication among ECUs, a novel key provisioning strategy, intelligent throughput management, and hardware signature mechanisms. The proposed architecture has been implemented, resorting to a commercial Multi-Protocol Vehicle Interface module, and the obtained results experimentally demonstrate the approach’s feasibility
Screening for significant chronic liver disease by using three simple ultrasound parameters
Objectives
Chronic liver diseases remain asymptomatic for many years. Consequently, patients are diagnosed belatedly, when cirrhosis is unmasked by lifethreatening complications. We aimed to identify simple ultrasound parameters for the screening of patients with unknown significant chronic liver disease.
Methods
Three hundred and twenty seven patients with chronic liver disease, liver biopsy, and ultrasound examination were included in the derivation set. 283 consecutive patients referred for ultrasound examination were included in the validation set; those selected according to the ultrasound parameters identified in the derivation set were then referred for specialized consultation including non-invasive fibrosis tests and ultimately liver biopsy if liver fibrosis was suspected.
Results
In the derivation set, three ultrasound parameters were independent predictors of severe fibrosis: liver surface irregularity, spleen length (>110 mm), and demodulation of hepatic veins. The association of ≥2 of the three above parameters provided 49.1% sensitivity and 86.9% specificity. In the validation set, at ≥2 of the three parameters were present in 23 (8%) of the patients. Among these patients, 8 had liver fibrosis (F ≥ 1), 5 had significant fibrosis (F  ≥2) and two cirrhosis.
Conclusion
The generalized search of three simple ultrasound signs in patients referred for abdominal ultrasound examination may be an easy way to detect those with silent but significant chronic liver disease
TAURUM P2T: Advanced secure CAN-FD architecture for road vehicle
Interconnected devices are growing very fast in today's automotive market, providing new and complex features that cover very different domains. This vast and continuous requirement for new features brings to impact areas categorized as real-time safety-critical devices, opening the possibility to add potential vulnerabilities. By analyzing the security vulnerabilities within vehicle networks, this paper aims at proposing a new generation of a secure architecture based on Controller Area Network (CAN) called TAURUM P2T. This new architecture looks at mitigating the vulnerabilities found in the current network systems of road vehicles by introducing a low-cost and efficient solution based on the introduction of a Secure CAN network able to implement a novel key provisioning strategy. The proposed architecture has been implemented, resorting to a commercial Multi-Protocol Vehicle Interface module, and the obtained results experimentally demonstrate the approach's feasibility
On-sky results of the adaptive optics MACAO for the new IR-spectrograph CRIRES at VLT
The adaptive optics MACAO has been implemented in 6 focii of the VLT
observatory, in three different flavors. We present in this paper the results
obtained during the commissioning of the last of these units, MACAO-CRIRES.
CRIRES is a high-resolution spectrograph, which efficiency will be improved by
a factor two at least for point-sources observations with a NGS brighter than
R=15. During the commissioning, Strehl exceeding 60% have been observed with
fair seeing conditions, and a general description of the performance of this
curvature adaptive optics system is done.Comment: SPIE conference 2006, Advances in adaptive optics, 12 pages, 11
figure
Combination of blood tests for significant fibrosis and cirrhosis improves the assessment of liver-prognosis in chronic hepatitis C
BACKGROUND: Recent longitudinal studies have emphasised the prognostic value of noninvasive tests of liver fibrosis and cross-sectional studies have shown their combination significantly improves diagnostic accuracy.
AIM: To compare the prognostic accuracy of six blood fibrosis tests and liver biopsy, and evaluate if test combination improves the liver-prognosis assessment in chronic hepatitis C (CHC).
METHODS: A total of 373 patients with compensated CHC, liver biopsy (Metavir F) and blood tests targeting fibrosis (APRI, FIB4, Fibrotest, Hepascore, FibroMeter) or cirrhosis (CirrhoMeter) were included. Significant liver-related events (SLRE) and liver-related deaths were recorded during follow-up (started the day of biopsy).
RESULTS: During the median follow-up of 9.5 years (3508 person-years), 47 patients had a SLRE and 23 patients died from liver-related causes. For the prediction of first SLRE, most blood tests allowed higher prognostication than Metavir F [Harrell C-index: 0.811 (95% CI: 0.751-0.868)] with a significant increase for FIB4: 0.879 [0.832-0.919] (P = 0.002), FibroMeter: 0.870 [0.812-0.922] (P = 0.005) and APRI: 0.861 [0.813-0.902] (P = 0.039). Multivariate analysis identified FibroMeter, CirrhoMeter and sustained viral response as independent predictors of first SLRE. CirrhoMeter was the only independent predictor of liver-related death. The combination of FibroMeter and CirrhoMeter classifications into a new FM/CM classification improved the liver-prognosis assessment compared to Metavir F staging or single tests by identifying five subgroups of patients with significantly different prognoses.
CONCLUSIONS: Some blood fibrosis tests are more accurate than liver biopsy for determining liver prognosis in CHC. A new combination of two complementary blood tests, one targeted for fibrosis and the other for cirrhosis, optimises assessment of liver-prognosis
Characterization of the biogenic volatile organic compounds (BVOCs) and analysis of the PR1 molecular marker in Vitis vinifera L. inoculated with the nematode Xiphinema index
Upon pathogen attack, plants very quickly undergo rather complex physico-chemical changes, such as the production of new chemicals or alterations in membrane and cell wall properties, to reduce disease damages. An underestimated threat is represented by root parasitic nematodes. In Vitis vinifera L., the nematode Xiphinema index is the unique vector of Grapevine fanleaf virus, responsible for fanleaf degeneration, one of the most widespread and economically damaging diseases worldwide. The aim of this study was to investigate changes in the emission of biogenic volatile organic compounds (BVOCs) in grapevines attacked by X. index. BVOCs play a role in plant defensive mechanisms and are synthetized in response to biotic damages. In our study, the BVOC profile was altered by the nematode feeding process. We found a decrease in \u3b2-ocimene and limonene monoterpene emissions, as well as an increase in \u3b1-farnesene and \u3b1-bergamotene sesquiterpene emissions in nematode-treated plants. Moreover, we evaluated the PR1 gene expression. The transcript level of PR1 gene was higher in the nematode-wounded roots, while in the leaf tissues it showed a lower expression compared to control grapevines
Evaluation of borage extracts as potential biostimulant using a phenomic, agronomic, physiological and biochemical approach
Biostimulants are substances able to improve water and nutrient use efficiency and counteract stress factors by enhancing primary and secondary metabolism. Premise of the work was to exploit raw extracts from leaves (LE) or flowers (FE) of Borago officinalis L., to enhance yield and quality of Lactuca sativa ‘Longifolia,’ and to set up a protocol to assess their effects. To this aim, an integrated study on agronomic, physiological and biochemical aspects, including also a phenomic approach, has been adopted. Extracts were diluted to 1 or 10 mL L–1, sprayed onto lettuce plants at the middle of the growing cycle and 1 day before harvest. Control plants were treated with water. Non-destructive analyses were conducted to assess the effect of extracts on biomass with an innovative imaging technique, and on leaf photosynthetic efficiency (chlorophyll a fluorescence and leaf gas exchanges). At harvest, the levels of ethylene, photosynthetic pigments, nitrate, and primary (sucrose and total sugars) and secondary (total phenols and flavonoids) metabolites, including the activity and levels of phenylalanine ammonia lyase (PAL) were assessed. Moreover, a preliminary study of the effects during postharvest was performed. Borage extracts enhanced the primary metabolism by increasing leaf pigments and photosynthetic activity. Plant fresh weight increased upon treatments with 10 mL L–1 doses, as correctly estimated by multi-view angles images. Chlorophyll a fluorescence data showed that FEs were able to increase the number of active reaction centers per cross section; a similar trend was observed for the performance index. Ethylene was three-fold lower in FEs treatments. Nitrate and sugar levels did not change in response to the different treatments. Total flavonoids and phenols, as well as the total protein levels, the in vitro PAL specific activity, and the levels of PAL-like polypeptides were increased by all borage extracts, with particular regard to FEs. FEs also proved efficient in preventing degradation and inducing an increase in photosynthetic pigments during storage. In conclusion, borage extracts, with particular regard to the flower ones, appear to indeed exert biostimulant effects on lettuce; future work will be required to further investigate on their efficacy in different conditions and/or species
Use of Genuine Sources of Ergot Resistance in Species of the \u3ci\u3edilatata\u3c/i\u3e Group of \u3ci\u3ePaspalum\u3c/i\u3e
Paspalum dilatatum Poir. (dallisgrass) is an excellent C4 forage for summer production, highly productive with a wide distribution within warm-temperate regions. P. dilatatum is native to South America with special relevance for milk and meat production since its forage quality is superior to that of other C4 forage grasses and it shows tolerance to frost and water stress. In situations of temperate and warm temperate climate, the presence of these species plays a key role in the ecological stability of the system due to the complementarity of the growth cycles between winter and summer grasses. Claviceps paspali (ergot) is a fungus that mainly parasitizes Paspalum spp., generating a structure called sclerotia, in which indole-diterpenoid alkaloids are isolated. Despite the excellent forage characteristics of Paspalum species, there is a need for the generation of varieties able to overcome two major limitations that were identified early on in this species, such as ergot susceptibility and seed production. With this objective, selected genotypes were crossed between apomictic and sexual species of different ploidy using P. malacophyllum as a source of immunity. Immunity to ergot has been evaluated in the field for two years in different representative regions of Uruguay and the accessions that did not get sick were selected as pollen donors. Crosses made with P. flavescens showed a germination percentage ranging between 1.7 and 7.09, while in P. dilatatum var. Chirú the range was reduced between 0.99 and 1.25 according to the employed parents. The hybrid nature of the progeny is being verified by microsatellites and functional markers associated with immunity and DNA content estimated by flow cytometry. This work aims to generate the basis to transfer immunity from P. malacophyllum in selected genotypes of Paspalum species predominant in Pampa biome and to improve seed production
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