Search results for "ibers"

Fiber-Optic Aqueous Dipping Sensor Based on Coaxial-Michelson Modal Interferometers

2009

Fiber-optic modal interferometers with a coaxial-Michelson configuration can be used to monitor aqueous solutions by simple dipping of few centimeters of a fiber tip. The fabrication of these sensors to work around 850 nm enables the use of compact, robust, and low-cost optical spectrum analyzers. The use of this type of portable sensor system to monitor sewage treatment plants is shown.

Imbalance between sympathetic and sensory innervation in peritoneal endometriosis

2011

To investigate possible mechanisms of pain pathophysiology in patients with peritoneal endometriosis, a clinical study on sensory and sympathetic nerve fibre sprouting in endometriosis was performed. Peritoneal lesions (n= 40) and healthy peritoneum (n= 12) were immunostained and analysed with anti-protein gene product 9.5 (PGP 9.5), anti-substance P (SP) and anti-tyrosine hydroxylase (TH), specific markers for intact nerve fibres, sensory nerve fibres and sympathetic nerve fibres, respectively, to identify the ratio of sympathetic and sensory nerve fibres. In addition, immune cell infiltrates in peritoneal endometriotic lesions were analysed and the nerve growth factor (NGF) and interleuki…

Serotoninergic innervation of nonprincipal cells in the cerebral cortex of the lizard Podarcis hispanica.

2004

The mechanism of serotoninergic transmission in the neo- and archicortex of mammals kis complex, including both synaptic and nonsynaptic components, direct actions on principal cells, and indirect effects mediated by GABAergic interneurons. Here we studied the termination pattern and synaptic organization of the serotoninergic afferents in the cerebral cortex of the lizard, Podarcis hispanica, which is considered to correspond in part to the mammalian hippocampal formation, with the aim of unraveling basic, phylogenetically preserved rules in the connectivity of this pathway. We demonstrate that serotoninergic afferents, visualized by immunostaining for serotonin itself, establish multiple …

A model for SFRC beams without shear reinforcement

2008

In this paper a physical model, for the prediction of ultimate shear strength of Steel Fibers Reinforced Concrete (SFRC) beams is developed from the plastic Crack Sliding Model (CSM) introduced by Zhang (1997), based on the hypothesis that cracks can be transformed into yield lines. In this work the effectiveness factors are recalculated for SFRC beams and some further developments are introduced in the CSM, taking into account the fundamental post cracking tensile strength contribute of SFRC. The proposed model is validate by a large set of tests collected in literature and some numerical analyses were carried out to show the influence of fibers on the failure beams mode.

Dalle utopie urbane ai paesaggi virtuali

2014

Le utopie di spazi urbani mai realizzati, a volte sono riproposte tramite molteplici re-interpretazioni progettuali; in tal modo spesso il progetto urbano prende le mosse da mondi iper-reali, all’interno di un spazio-tipo che permette la definizione di un nuovo luogo, collocato in un tempo indeterminato, quasi come fosse un mondo ludico che stimola e costituisce parte integrante dell’immaginazione. L’articolo propone un approfondimento sull’evoluzione storica del concetto di città ideale, fino ad arrivare alle utopie visionarie degli anni ’70, per concludere con i paesaggi astratti dei disegni di Franco Purini e le molteplici dimensioni del ciber-spazio. The utopian abstraction about urban …

Analysis of the Parameters Affecting the Stiffness of Short Sisal Fiber Biocomposites Manufactured by Compression-Molding

2021

The use of natural fiber-based composites is on the rise in many industries. Thanks to their eco-sustainability, these innovative materials make it possible to adapt the production of components, systems and machines to the increasingly stringent regulations on environmental protection, while at the same time reducing production costs, weight and operating costs. Optimizing the mechanical properties of biocomposites is an important goal of applied research. In this work, using a new numerical approach, the effects of the volume fraction, average length, distribution of orientation and curvature of fibers on the Young’s modulus of a biocomposite reinforced with short natural fibers were stud…

Conductive polymer composites based on cyclic butylene terephtalate oligimers and carbon fibers

2007

Lemongrass Plant as Potential Sources of Reinforcement for Biocomposites: A Preliminary Experimental Comparison Between Leaf and Culm Fibers

2022

AbstractNowadays, the world requires more sustainable and eco-friendly materials to replace or limit the usage of synthetic materials. Moreover, several researchers focused their attention on the use of agricultural sources as reinforcement for biocomposites since they are abundant, cost-effective and environmentally favorable sources. In such a context, purpose of the present paper is the evaluation of lemongrass plant (Cymbopogon flexuosus) as possible source of natural reinforcement for biocomposites. To this aim, natural fibers were obtained from the leaf and the stem of lemongrass and their main properties were compared for the first time. To this scope, mechanical and thermal characte…

Nanofibrous Polymeric Membranes for Air Filtration Application: A Review of Progress after the COVID‐19 Pandemic

2023

Air pollution is one of the major global problems causing around 7 million dead per year. In fact, a connection between infectious disease transmission, including COVID-19, and air pollution has been proved: COVID-19 consequences on human health are found to be more severe in areas characterized by high levels of particulate matter (PM). Therefore, after the COVID-19 pandemic, the production of air filtration devices with high filtration efficiency has gained more and more attention. Herein, a review of the post-COVID-19 pandemic progress in nanofibrous polymeric membranes for air filtration is provided. First, a brief discussion on the different types of filtration mechanism and the key pa…

Flax–Glass Fiber Reinforced Hybrid Composites Exposed to a Salt-Fog/Dry Cycle: A Simplified Approach to Predict Their Performance Recovery

2023

Despite natural fibers gaining significant attention in recent decades, their limited performance and poor durability under humid environments cannot allow them to fully replace their synthetic counterparts as reinforcement for structural composites. In such a context, this paper aims to investigate how exposure to a humid/dry cycle affects the mechanical response of epoxy laminates reinforced with flax and glass fibers. In particular, the main goal is to assess the performance evolution of a glass–flax hybridized stacking sequence in comparison with the full glass and flax fiber reinforced composites. To this end, the investigated composites were first exposed to salt-fog for 15 or 30 days…