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211.
Yizhe Guo Fan Wu Guan-Hua Dun Tianrui Cui Yanming Liu Xichao Tan Yancong Qiao Mario Lanza He Tian Yi Yang Tian-Ling Ren 《Advanced functional materials》2023,33(5):2208055
Biological synapses are the operational connection of the neurons for signal transmission in neuromorphic networks and hardware implementation combined with electrospun 1D nanofibers have realized its functionality for complicated computing tasks in basic three-terminal field-effect transistors with gate-controlled channel conductance. However, it still lacks the fundamental understanding that how the technological parameters influence the signal intensity of the information processing in the neural systems for the nanofiber-based synaptic transistors. Here, by tuning the electrospinning parameters and introducing the channel surface doping, an electrospun ZnO nanofiber-based transistor with tunable plasticity is presented to emulate the changing synaptic functions. The underlying mechanism of influence of carrier concentration and mobility on the device's electrical and synaptic performance is revealed as well. Short-term plasticity behaviors including paired-pulse facilitation, spike duration-dependent plasticity, and dynamic filtering are tuned in this fiber-based device. Furthermore, Perovskite-doped devices with ultralow energy consumption down to ≈0.2554 fJ and their handwritten recognition application show the great potential of synaptic transistors based on a 1D nanostructure active layer for building next-generation neuromorphic networks. 相似文献
212.
This study was designed to compare the chemistry of elaiosomes of three sympatric species ofTrillium to discover if there are correlations between chemistry and dispersal rates by ants. We quantified the amount of proteins and neutral lipids and qualitatively analyzed the fatty acids occurring in triglyceride, diglyceride, monoglyceride, and free fatty acid fractions.T. grandiflorum had the highest lipid concentration per milligram of protein and the highest total lipid per elaiosome, followed byT. erectum and then byT. undulatum. Oleic acid (181) was abundant in all lipid fractions of each species. This fatty acid, which is responsible for corpse-carrying behavior in some ants, probably causes ants to pick up diaspores. Linoleic acid (182) is relatively abundant inT. erectum andT. grandiflorum but not inT. undulatum and may cause ants that have picked up diaspores to move (carry) those diaspores back to the nest. Total elaiosome mass and fatty acid composition appear to explain whyT. erectum is dispersed most rapidly and why ants that have picked up elaiosomes move moreT. grandiflorum thanT. undulatum diaspores. 相似文献
213.
Giulio Iovine Carmela Vennari Stefano Luigi Gariano Tommaso Caloiero Giuseppe Lanza Nicola Nicolino Stefania Suriano Giuseppe Ferraro Mario Parise 《Bulletin of Engineering Geology and the Environment》2016,75(1):37-52
The occurrence of sinkholes not directly related to karst has been determined in several areas worldwide in recent years. These phenomena may be particularly dangerous to humans and infrastructure due to their subtle origin and need to be carefully examined. In this work, we describe five sinkholes recently identified in a hilly setting of Southern Italy characterized by Pliocene conglomerate and sand, and variously dislocated by tectonic structures. The sinkholes were examined by different methods (interpretation of multi-temporal aerial photos, geological, geomorphological and geophysical surveys). An historical analysis was performed to collect and critically evaluate information regarding the age of the phenomena. Based on this information, it can be conjectured that two of the five sinkholes developed during the 2000–2001 winter; two of the remaining probably originated during the 70s; the last one opened sometime between February 2001 and November 2007. Based on such chronology, attempts have been performed to identify the likely triggers, through hydrological and seismic analyses. In both cases, no immediate correlation could be found. The origin of the studied phenomena remains uncertain, and may be related to sub-cutaneous erosion, in an area that is renowned to be rich in groundwater. Local changes in the water table, related to climate and/or man-induced activities, may have triggered the development of the cover suffusion-type sinkholes. The present work highlights the potential for this type of phenomena to occur in geological settings without the direct presence of soluble rocks at the surface, a condition quite common in Southern Italy, and the need to carry out further studies in order to better comprehend their mechanisms of origin and successive evolution, and to properly evaluate the related hazard. 相似文献
214.
T. A. M. Haemers D. G. Rickerby F. Lanza F. Geiger E. J. Mittemeijer 《Journal of Materials Science》2000,35(22):5691-5698
Stainless steel substrates were hardfaced with laser melted Colmonoy applying a continuous wire injection technique using a CO2 laser. The microstructures of single pass laser clad deposits were examined and related to workpiece traverse velocity at constant laser output. Particular attention was paid to the effect of dilution of the cladding alloy due to convectional mixing with the partially melted substrate material. The solidification microstructure of the rapidly cooled cladded layer consisted predominantly of nickel rich cellular dendrites and interdendritic lamellar eutectic borides. 相似文献
215.
Elia Hoz Zavala and Guadalupe de la Lanza Espino 《Lakes & Reservoirs: Research and Management》2000,5(4):249-260
The environmental characteristics and degree of pollution of a jagüey (a small, shallow tropical water‐body) in Mexico were identified by means of an environmental impact matrix. Jagüeys are important as their main sources of water are the subsurface water‐table and rainfall, however, they have not been studied because of their small size. A flow diagram was designed to incorporate the main climatic, geological and hydrological environmental factors, as well as physico‐chemical data on sediment and water qualities, and biological, technostructural and socioeconomic aspects. The resulting index of –90 in the environmental impact matrix indicates a severe negative impact on jagüeys from the input of allochtonous nutrients because of their small depth, limited circulation and the high rate of evaporation. The jagüeys studied appear in a state of hypertrophy and senility, despite geological youth. 相似文献
216.
Pan D Pramanik M Senpan A Wickline SA Wang LV Lanza GM 《Journal of nanoscience and nanotechnology》2010,10(12):8118-8123
Molecular imaging techniques now allow recognition of early biochemical, physiological, and anatomical changes before manifestation of gross pathological changes. Photoacoustic imaging represents a novel non-ionizing detection technique that combines the advantages of optical and ultrasound imaging. Noninvasive photoacoustic tomography (PAT) imaging in combination with nanoparticle-based contrast agents show promise in improved detection and diagnosis of cardiovascular and cancer related diseases. In this report, a novel strategy is introduced to achieve self-assembled colloidal gold nanorods, which are constrained to the vasculature. Gold nanorods (2-4 nm) were incorporated into the core of self-assembled lipid-encapsulated nanoparticles (sGNR) (approximately 130 nm), providing more than hundreds of gold atoms per nanoparticle of 20% colloid suspension. The physico-chemical characterization in solution and anhydrous state with analytical techniques demonstrated that the particles were spherical and highly mono dispersed. In addition to the synthesis and characterization, sensitive near-infrared photoacoustic detection was impressively demonstrated in vitro. 相似文献
217.
Mario R. Romano Fiammetta Catania Filippo Confalonieri Piero Zollet Davide Allegrini Jessica Sergenti Francesco B. Lanza Mariantonia Ferrara Martina Angi 《International journal of molecular sciences》2021,22(18)
Toxic tumour syndrome (TTS) is a particularly aggressive form of secondary vasculopathy occurring after radiation therapy of uveal melanoma due to the persistence of the necrotic tumour mass inside the eye. The development of TTS confers a particularly unfavourable functional and anatomical ocular prognosis, ultimately requiring enucleation in most cases if untreated. Vitreoretinal (VR) surgery has been successfully applied for treatment and prevention of TTS using both resecting and non-resecting techniques. In this systematic review, we aim to define characteristics of uveal melanomas benefiting the most from secondary VR surgery and to outline the optimal type and timing of VR intervention in such cases. Analysis of the literature reveals that endoresection should be performed within 3 months after radiotherapy to tumours thicker than 7 mm and with a largest basal diameter between 8 mm and 15 mm with post-equatorial location, especially after proton beam treatment. Alternatively, endodrainage remains a valid therapeutic option in eyes with macula-off retinal detachment, tumour diameter larger than 15 mm or ciliary body involvement. VR surgery can be successful in the management of TTS following radiotherapy for uveal melanoma when timing and indication are appropriately evaluated. 相似文献
218.
Laura Lupini Roberta Roncarati Lorenzo Belluomini Federica Lancia Cristian Bassi Lucilla DAbundo Angelo Michilli Paola Guerriero Alessandra Fasano Elisa Tiberi Andrea Salamone Donato Michele Cosi Elena Saccenti Valentina Tagliatti Iva Maestri Silvia Sabbioni Stefano Volinia Roberta Gaf Giovanni Lanza Antonio Frassoldati Massimo Negrini 《International journal of molecular sciences》2022,23(15)
Liquid biopsy has advantages over tissue biopsy, but also some technical limitations that hinder its wide use in clinical applications. In this study, we aimed to evaluate the usefulness of liquid biopsy for the clinical management of patients with advanced-stage oncogene-addicted non-small-cell lung adenocarcinomas. The investigation was conducted on a series of cases—641 plasma samples from 57 patients—collected in a prospective consecutive manner, which allowed us to assess the benefits and limitations of the approach in a real-world clinical context. Thirteen samples were collected at diagnosis, and the additional samples during the periodic follow-up visits. At diagnosis, we detected mutations in ctDNA in 10 of the 13 cases (77%). During follow-up, 36 patients progressed. In this subset of patients, molecular analyses of plasma DNA/RNA at progression revealed the appearance of mutations in 29 patients (80.6%). Mutations in ctDNA/RNA were typically detected an average of 80 days earlier than disease progression assessed by RECIST or clinical evaluations. Among the cases positive for mutations, we observed 13 de novo mutations, responsible for the development of resistance to therapy. This study allowed us to highlight the advantages and disadvantages of liquid biopsy, which led to suggesting algorithms for the use of liquid biopsy analyses at diagnosis and during monitoring of therapy response. 相似文献
219.
In the last three decades, companies have intensified their global business activities with suppliers and thereby were able to focus on their core competencies. Today, supplier development in low cost countries is of increasing strategic importance due to its high cost-cutting potential; however, especially low cost country sourcing features high decision complexity and challenges due to changing corporate environment. This paper presents a three step approach to include uncertainty and flexibility into the decision making process on supplier development, using real options valuation. First, the procurement object is analysed followed by an analysis of the corporate environment in which dynamic environmental factors and risks are evaluated. In the final step, the real options value of the supplier development project is determined, including market risks and flexibility of action. The methodology of real options valuation is a useful tool for supplier evaluation in a low cost country environment since it provides a gradual increase in prediction quality through a project-accompanying evaluation and therefore allows for more reliable planning. 相似文献
220.
Barbara Lanza Maria G. Di Serio Lucia Giansante Giuseppina Di Loreto Francesca Russi Luciana Di Giacinto 《International Journal of Food Science & Technology》2013,48(12):2630-2637
Two types of products obtained from the processing of Olea europaea cv ‘Taggiasca’ were monitored: pitted olives and olive paste preserved in monovarietal extra‐virgin olive oil of the same variety. The aim of this study was to follow the trends in the main physico‐chemical and sensory parameters related to the quality of these table olives and their covering oils, for simulation of the shelf‐life conditions. From all of the analyses carried out, it can be concluded that the optimum time of storage of these two products packaged in glass jars at room temperature (between 18 and 25 °C) and under artificial light and away from heat sources is approximately 9 months. After 9 months of storage, the covering oils were greatly affected by the contact with the broken fruit, which was accompanied by reductions in their antioxidant content due to the thermal treatment. The oxidative effects seen through physico‐chemical analyses are in agreement with the organoleptic analysis. 相似文献