6 research outputs found

    Produzione, qualità e analisi della filiera produttiva del lino da fibra in Italia

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    Fibre flax (Linum usitatissimum L.) is disappeared from the ltalian crop systems, while the textile industry has reached a leading position. The reintroduction of the crop is than potentially promising but the crop techniques and the production processes have to be set up. In 12 environments: crop development and growth, cultivar response, straw, fibre and seed yields, and fibre quality were analysed in the 1992-98 period. The data pointed out crop cycles of 176 and 110 d for the autumn and the spring sowing time respectively, corresponding to 1125 and 990°C d cumulated growing degree. Straw yield at pulling was on average of 6.3 t ha-1, with relevant differences among years and environrnents. Early maturity cultivar yielded more in the less favourable sites. N fertilization was occasionally relevant, and a generally distributions of 60 kg N ha-1 was the more effective. In the Mediterranean environments, with the autumn, sowing flax was more productive and the yield steady. The long fibre ratio was often low (10-13%) and the quality uneven because of the insufficient cleanliness due to retting difficulties. Occasionally, the value of the fibre was affected by the insufficient stem length. In the less dense crop, the seed yield was on average 0.9 t ha-1. Such productions were similar to those assessed for the more dense crop. In conclusion: because of the complexity of the interactions among the crop growth, the yield, the retting process and the fibre quality flax reintroduction is doubtful. In the production processes retting seems to be the crucial phase. Il lino da fibra (Linum usitatissimum L.) è da tempo assente negli ordinamenti colturali italiani, mentre è assai importante l'industria di filatura. La reintroduzione della coltura appare quindi potenzialmente promettente, ma richiede la messa a punto dell'agrotecnica e della filiera produttiva. Nel periodo 1992-1998 in 12 ambienti sono stati esaminati: lo sviluppo e la crescita della coltura, l'adattamento di cultivar, la produzione di paglia, fibra e seme, la resa alla stigliatura, la qualità della fibra. I dati raccolti evidenziano cicli colturali in media di 176 e 110 d rispettivamente per le semine autunnali (ambienti del centro-sud) e vemino-primaverili; corrispondenti a somme termiche di 1125 e 990°C d. La produzione di paglia alla estirpatura è stata in media di 6.3 t ha-1 con valori assai variabili tra annate e ambienti. Le varietà a ciclo corto sono apparse migliori nelle condizioni difficili. L'effetto della concimazione azotata è apparsa talvolta rilevante e comunque con dosi ottimali prossime a 60 kg ha-1 di N. Negli ambienti del centro-sud le semine autunnali si sono dimostrate spesso le più interessanti e sicure. La resa in fibra lunga è stata bassa (10-13%) e la qualità variabile per la scarsa pulizia dovuta alle difficoltà di macerazione. La modesta lunghezza tecnica dello stelo sovente riduce il valore del prodotto. In coltura rada, la produzione di seme è variata da 0.5 a 1.5 t ha-1; tali valori non si sono discostati in modo apprezzabile da quelli ottenuti in coltura fitta. In conclusione, la diffusione del lino appare problematica per le complesse interazioni tra la produzione, il processo di macerazione e la qualità della fibra. Soprattutto la macerazione appare il passaggio chiave

    Stability for the acoustic scattering problem for sound-hard scatterers

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    We study the stability for the direct acoustic scattering problem with sound-hard scatterers with minimal regularity assumptions on the scatterers. The main tool we use for this purpose is the convergence in the sense of Mosco. We obtain uniform decay estimates for scattered fields and we investigate how a sound-hard screen may be approximated by thin sound-hard obstacles

    Method for biomarking textile materials

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    The present invention describes a process designed to integrate biomarkers into textile substrates. The invention is directed to any kind of textile materials in form of loose fibres, tops, tow, sliver, yarn, fabric (woven, knitted, nonwoven, braided, etc.), garment. Textile materials can be made of natural or man-made fibres (artificial, synthetic) or their blends. The biomarkers of the invention are proteins, preferably endowed with biocatalytic activity. The biomarker carrier media include aqueous solutions of textile auxiliaries and finishes. The presence of the biomarker is detected by means of specific activity tests by applying the concept of biosensing. Visual inspection is generally sufficient to authenticate the biomarker

    Adoption of Hybrid MRI-Linac Systems for the Treatment of Brain Tumors: A Systematic Review of the Current Literature Regarding Clinical and Technical Features

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    Background Possible advantages of magnetic resonance (MR)-guided radiation therapy (MRgRT) for the treatment of brain tumors include improved definition of treatment volumes and organs at risk (OARs) that could allow margin reductions, resulting in limited dose to the OARs and/or dose escalation to target volumes. Recently, hybrid systems integrating a linear accelerator and an magnetic resonance imaging (MRI) scan (MRI-linacs, MRL) have been introduced, that could potentially lead to a fully MRI-based treatment workflow. Methods We performed a systematic review of the published literature regarding the adoption of MRL for the treatment of primary or secondary brain tumors (last update November 3, 2022), retrieving a total of 2487 records; after a selection based on title and abstracts, the full text of 74 articles was analyzed, finally resulting in the 52 papers included in this review. Results and discussion Several solutions have been implemented to achieve a paradigm shift from CT-based radiotherapy to MRgRT, such as the management of geometric integrity and the definition of synthetic CT models that estimate electron density. Multiple sequences have been optimized to acquire images with adequate quality with on-board MR scanner in limited times. Various sophisticated algorithms have been developed to compensate the impact of magnetic field on dose distribution and calculate daily adaptive plans in a few minutes with satisfactory dosimetric parameters for the treatment of primary brain tumors and cerebral metastases. Dosimetric studies and preliminary clinical experiences demonstrated the feasibility of treating brain lesions with MRL. Conclusions The adoption of an MRI-only workflow is feasible and could offer several advantages for the treatment of brain tumors, including superior image quality for lesions and OARs and the possibility to adapt the treatment plan on the basis of daily MRI. The growing body of clinical data will clarify the potential benefit in terms of toxicity and response to treatment

    Monetary Policy Shocks and Transmission in Italy: a VAR Analysis

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