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71.
Abbate F Guerrera MC Montalbano G De Carlos F Suárez AÁ Ciriaco E Germanà A 《Microscopy research and technique》2012,75(5):643-649
The European sea bass, a member of the Moronidae family, is a food fish, considered one of the first models for the intensive breeding in salt water. It has nowadays an important and increasing presence in the international fishing markets. Sea basses are carnivorous, feeding on little fishes and invertebrates. Considering the important role of the tongue during the intraoral transport and the swallowing of food, scarce data are present in literature about its morphology. The aim of this study was to analyze the morphology of the tongue by means of scanning electron and light microscopy. Adult sea basses were obtained from the aquarium of the Sicilian Center of Experimental Ichthyiopathology of the University of Messina. The fishes were anaesthetized with MS 222 and the heads were then quickly removed and processed for the paraffin embedding and SEM processing. Three different tongue regions could be distinguished: an apex, a body, and a root. Scanning electron and light microscopy showed the presence of numerous canine-like teeth, surrounded by taste buds and numerous fungiform and conical papillae. The teeth were curved and their tips were posteriorly oriented. The results confirm, in teleosts too, the fundamental role of the tongue in the mechanics of food ingestion. Moreover, the presence of taste buds demonstrates the interaction of food processing and taste. These data could be a potential source to identify new and better methods of nutrition in the breeding of this fish. 相似文献
72.
Giuseppe Papa Antonino Romano Donato Quaratino Marina Di Fonso Marinella Viola Maria Cristina Artesani Sabina Sernia Mario Di Gioacchino Alberto Venuti 《The Science of the total environment》2001,270(1-3)
In the last few years Cupressus sempervirens has been identified as the cause of an increasing number of cases of late winter-early spring pollinosis in Mediterranean countries. We conducted a 4-year retrospective study of a large group of subjects with documented allergic respiratory disease in order to determine the prevalence, clinical significance and annual rate of sensitization to C. sempervirens pollen. Anamnestic data and skin prick tests (SPT) with common aeroallergens and C. sempervirens extract were collected from 1397 subjects (712 male and 685 female) resident in Latium, a region in central Italy, with complaints related to upper- or lower-respiratory-tract disorders or conjunctival disease. Two hundred and forty-three subjects (17.4%) showed positive results to C. sempervirens extract; 47 (19.3%) of them were monosensitized. The annual sensitization rate of SPT positivity to C. sempervirens varied from 7.2% in 1995 to 22% in 1998. All the subjects monosensitized to cypress pollen had symptoms from January through April. Our study suggests that sensitivity to C. sempervirens is responsible for respiratory symptoms in an increasing percentage of subjects. Further studies are needed to determine its frequency at the national level. 相似文献
73.
Giuseppe Calcagno Antonino Staiano Giuliana Fortunato Vincenzo Brescia-Morra Rosario Liguori Silvana Capone Alessandro Filla Lucia Sacchetti 《Information Sciences》2010,180(21):4153-185
Multiple sclerosis is an idiopathic inflammatory disease characterized by multiple focal lesions in the white matter of the central nervous system. Multiple sclerosis patients are usually treated with interferon-β, but disease activity decrease in only 30-40% of patients. In the attempt to differentiate between responders and non-responders, we screened the main genes involved in the interferon signaling pathway for 38 single nucleotide polymorphisms (SNPs) in a multiple sclerosis Caucasian population from South Italy. We then analyzed the data using a multilayer perceptron neural network-based approach, in which we evaluated the global weight of a set of SNPs localized in different genes and their association with response to interferon therapy through a feature selection procedure (a combination of automatic relevance determination and backward elimination). The neural approach appears to be a useful tool in identifying gene polymorphisms involved in the response of patients to interferon therapy: 2 out of 5 genes were identified as containing 4 out of 38 significant single nucleotide polymorphisms, with a global accuracy of 70% in predicting responder and non-responder patients. 相似文献
74.
Katiuscia Dallaglio Tiziana Petrachi Alessandra Marconi Francesca Truzzi Roberta Lotti Annalisa Saltari Paolo Morandi Mario Puviani Antonino Maiorana Dennis R. Roop Carlo Pincelli 《International journal of molecular sciences》2013,14(10):19540-19555
In human epidermis, keratinocyte stem cells (KSC) are characterized by high levels of β1-integrin, resulting in the rapid adhesion to type IV collagen. Since epithelial tumors originate from KSC, we evaluated the features of rapidly adhering (RAD) keratinocytes derived from primary human squamous cell carcinoma of the skin (cSCC). RAD cells expressed higher levels of survivin, a KSC marker, as compared to non-rapidly adhering (NRAD) cells. Moreover, RAD cells proliferated to a greater extent and were more efficient in forming colonies than NRAD cells. RAD cells also migrated significantly better than NRAD cells. When seeded in a silicone chamber and grafted onto the back skin of NOD SCID mice, RAD cells formed tumors 2–4 fold bigger than those derived from NRAD cells. In tumors derived from RAD cells, the mitotic index was significantly higher than in those derived from NRAD cells, while Ki-67 and survivin expression were more pronounced in RAD tumors. This study suggests that SCC RAD stem cells play a critical role in the formation and development of epithelial tumors. 相似文献
75.
Roberto Baldoni Ricardo Jiménez-Peris Marta Patiño-Martínez Leonardo Querzoni Antonino Virgillito 《Journal of Parallel and Distributed Computing》2008
Peer-to-peer systems (P2P) have become a popular technique to design large-scale distributed applications in unmanaged inter-domain settings, such as file sharing or chat systems, thanks to their capabilities to self-organize and evenly split the load among peers. Recently, enterprises owning a large IT hardware and software infrastructure started looking at these P2P technologies as a means both to reduce costs and to help their technical divisions to manage huge number of devices characterized by a high level of cooperation and a relatively low churn. Gaining a quick exclusive access to the system for maintenance or auditing purposes in these enterprise infrastructures is a fundamental operation to be implemented. Conversely, this kind of operation is usually not an issue in the previously mentioned inter-domain setting, where peers are inherently independent and cannot be managed. 相似文献
76.
Costantino Del Gaudio Giorgio Antonino Licciardi 《Fullerenes, Nanotubes and Carbon Nanostructures》2019,27(5):446-452
An effective filler dispersion within a polymeric matrix is known to be a crucial requirement for obtaining the desired performance from a composite. A quantification of this parameter cannot be always easily achieved and several methodologies have been proposed so far, generally based on complex image processing algorithms. However, no standard has been established yet.
In order to contribute to the quantitative evaluation of the filler dispersion in a polymeric matrix, a novel straightforward two-dimensional alternative method based on the analysis of electron microscopy micrographs is here proposed. Several case studies were considered to test the reliability of the approach, providing as resulting output, either a qualitative polar plot representative of the analyzed image and an index to measure the filler dispersion. 相似文献
77.
Silvio Barbarelli Gaetano Florio Mario Amelio Nino Michele Scomaienchi Antonino Cutrupi ManuelSanchez Blanco Giacomo Lo Zupone 《能源与动力工程:英文版》2014,(3):476-486
Tidal currents are a resource of great potentiality and not yet fully explored. Several efforts have been made to exploit these resources, but the costs associated to the deployment of tidal plants in marine environments are usually too high. The aim of this work is to present a system able to handle with the above mentioned problems, through the development of a particular hydrokinetic turbine design. In previous works, the authors described a basic turbine configuration achieving interesting performances, although some operational inconveniences were detected. Those problems have been existing so the solution should be optimized and redesigned. As a result, a new design of the turbine is proposed, consisting of a double rotor spinning in opposite directions in order to balance the induced mechanical torque. From preliminary evaluations related to the Messina Strait tidal cycles (Punta Pezzo site, RC, Italy), a single 12 m diameter turbine can supply a power of about 500 kW with a peak current speed of 3 m/s and deliver up to 450 MWh/year. 相似文献
78.
Rosanna Migliore Matteo Scala Anna Napoli Antonino Messina 《Journal of Engineering Mathematics》2013,82(1):187-197
A microscopic master equation describing the dynamics of two qubits coupled via a nonlinear mediator is constructed supposing that the two qubits, as well as the nonlinear mode, interact, each with its own independent bosonic bath. Generally speaking the master equation derived in this way represents a more appropriate tool for studying the dynamics of open quantum systems. Indeed we show that it is more complex than the phenomenological master equation, constructed simply adding ad hoc dissipative terms. 相似文献
79.
Pietro Paolo Corso Antonino Di Piazza Emilio Fiordilino Leonardo Lo Cascio Franco Persico 《Journal of Modern Optics》2013,60(8):1373-1387
Abstract The electromagnetic spectrum emitted by a one-dimensional atom driven by a strong laser field is obtained by use of the acceleration form and interpreted by means of few general properties of the matrix elements of the acceleration operator. We show that the emission occurs essentially in a region near the atomic core where the acceleration is significant and we investigate the role of the various emission channels arising from interference effects between transitions involving the bare atomic levels. 相似文献
80.