1,066 research outputs found

    Propagation of Artemisia arborescens L. by stem-cutting: adventitious root formation under different conditions

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    Artemisia arborescens L. has gained a strong importance worldwide due to its many industrial uses and it has been recently considered as ornamental plant. A major constraint to its widespread cultivation is represented, by far, by the scarce availability of high-quality plant material for field establishment; hence, development of a fast and effective methods for its vegetative propagation is needed. An experiment was conducted to assess the effects of different harvest periods, NAA, and rooting substrates on rooting of stem cuttings of A. arborescens. Semi hardwood cuttings were collected from wild plants in February, April, and November. Half of the material was treated with 0.4% NAA and placed on different mixtures of sphagnum peat and perlite (2 : 1, 1 : 1, and 1 : 2 v/v) under mist. After 40 days the percentage of rooted cuttings was significantly influenced by the harvest period as cuttings collected in February showed the highest rooting rate, and numerous alive but not rooted cuttings evidenced callus formation. In contrast, the use of different rooting substrates as well as NAA addition did not show any significant effect on rooting capacity. The best results, in terms of root number (4.2) and root length (8.8 cm), were achieved on cuttings grown in a 1 : 1 v/v sphagnum peat : perlite mixture, without NAA application

    INTEGRATED 3D SURVEY FOR THE DOCUMENTATION AND VISUALIZATION OF A ROCK-CUT UNDERGROUND BUILT HERITAGE

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    Abstract. The research presented here is part of an on-going research focused on the 3D documentation of rock-cut Underground Built Heritage with a complex morphology and characterised by narrow spaces, the Hypogeum of Calaforno (province of Ragusa, Sicily). It is one of the most interesting prehistoric monuments in Sicily in terms of size and unique rock-cut architecture. Various digital techniques have been tested over the years on the site, to represent its spatiality, such as Laser Scanner and Structure from Motion. The proposed methodological approach for the knowledge and the documentation of this archaeological site is based on an interdisciplinary approach involving archaeological and engineering disciplines. This paper focuses on the use of expeditious techniques such as iMMS (indoor Mobile Mapping Systems) based on SLAM (Simultaneous Localization and Mapping) and on the comparison of different surveying equipment in order to verify data quality and accuracy, as well as the inherent advantages of using one technology over another in relation to the characteristics of the site. Through the global verification of TLS and SLAM model reliability, we maintain that such research can contribute to enriching the protocols surrounding the archaeological investigation of sites characterized by complex morphology, irregular surfaces, narrow spaces, specific chromatic features, scarce or total lack of lighting, and physical obstacles

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    Chemical and physical characterization of thermal aggregation of model proteins modulated by zinc (II) and copper (II) ions.

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    BACKGROUND: Metal ions are implicated in protein aggregation processes of several neurodegenerative pathologies, where the protein deposition occurs, and in the biotechnology field like the food technology where many processes in food manufacturing are based on thermal treatments. OBJECTIVE: The influence of Cu2+ or Zn2+ ions on the thermal aggregation process of Bovine beta-lactoglobulin (BLG) and Bovine Serum Albumin (BSA), two protein models, was studied with the aim of delineating the role of these ions in the protein aggregation kinetics and to clarify the related molecular mechanisms. METHODS: The protein structure changes were monitored by Raman spectroscopy, whereas the aggregate growth was followed by Dynamic Light Scattering measurements. RESULTS: Both metal ions are able to favour the BLG aggregation, whereas only Zn2+ ions have a promoter effect on the thermal aggregation of BSA. The reason of this different behaviour is that the BLG aggregation evolution is manly affected by the redistribution of charges, whereas that of BSA by the metal coordination binding which depends on metal. CONCLUSIONS: Raman spectroscopy, combined with dynamic light scattering experiments, was very useful in identifying the role played by Cu2+ and Zn2+ on the aggregation pathways of BLG and BSA. The results provide evidence for the role of histidine residues both in the redistribution of charges and in the two modes of metal binding that take place in BLG- and BSA-containing systems, respectively

    LOW COST TECHNIQUES FOR THE DIGITAL SURVEY OF A MINOAN ARCHITECTURE IN THE ARCHEOLOGICAL SITE OF PHAISTOS (CRETE)

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    Abstract. The paper shows the results of an experimentation on the use of low cost tools such as action cameras for the photogrammetric surveying of relevant archaeological sites characterized by the presence of narrow and complex rooms. The archaeological site chosen for this experimentation is the South-Western Quarter, also known as Quartiere Levi, of the Minoan Palace of Phaistos (Crete), one of only two cases of buildings surviving up to the third floor in the Aegean world. The research foresaw the setting up of a pipeline aimed at obtaining a complete scaled, photorealistic and navigable 3D model, with a considerable economy in terms of work time and number of photographs. For this purpose, many efforts have been paid on solving all the issues related to the complexity of the site and on comparing the performances of traditional (Canon EOS 70D) and action (GoPro Black Hero 6) cameras as well as of two of the current most used software in the field

    A computational study on temperature variations in mrgfus treatments using prf thermometry techniques and optical probes

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    Structural and metabolic imaging are fundamental for diagnosis, treatment and follow-up in oncology. Beyond the well-established diagnostic imaging applications, ultrasounds are currently emerging in the clinical practice as a noninvasive technology for therapy. Indeed, the sound waves can be used to increase the temperature inside the target solid tumors, leading to apoptosis or necrosis of neoplastic tissues. The Magnetic resonance-guided focused ultrasound surgery (MRgFUS) technology represents a valid application of this ultrasound property, mainly used in oncology and neurology. In this paper; patient safety during MRgFUS treatments was investigated by a series of experiments in a tissue-mimicking phantom and performing ex vivo skin samples, to promptly identify unwanted temperature rises. The acquired MR images, used to evaluate the temperature in the treated areas, were analyzed to compare classical proton resonance frequency (PRF) shift techniques and referenceless thermometry methods to accurately assess the temperature variations. We exploited radial basis function (RBF) neural networks for referenceless thermometry and compared the results against interferometric optical fiber measurements. The experimental measurements were obtained using a set of interferometric optical fibers aimed at quantifying temperature variations directly in the sonication areas. The temperature increases during the treatment were not accurately detected by MRI-based referenceless thermometry methods, and more sensitive measurement systems, such as optical fibers, would be required. In-depth studies about these aspects are needed to monitor temperature and improve safety during MRgFUS treatments

    Influence of dissipation on the extraction of quantum states via repeated measurements

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    A quantum system put in interaction with another one that is repeatedly measured is subject to a non-unitary dynamics, through which it is possible to extract subspaces. This key idea has been exploited to propose schemes aimed at the generation of pure quantum states (purification). All such schemes have so far been considered in the ideal situations of isolated systems. In this paper, we analyze the influence of non-negligible interactions with environment during the extraction process, with the scope of investigating the possibility of purifying the state of a system in spite of the sources of dissipation. A general framework is presented and a paradigmatic example consisting of two interacting spins immersed in a bosonic bath is studied. The effectiveness of the purification scheme is discussed in terms of purity for different values of the relevant parameters and in connection with the bath temperature.Comment: 10 pages, 3 figure
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