A RECONSTRUCTION OF THE GREEK-ROMAN REPEATING CATAPULT

An “automatic” repeating weapon used by the Roman army is presented. Firstly a short description is shown of the working principle of the torsion motor that powered the Greek-Roman catapults. This is followed by the description of the reconstructions of these ancient weapons made by those scientists who studied repeating catapults. The authors then propose their own reconstruction. The latter differs from the previous ones because it proposes a different working cycle that is almost automatic and much safer for the operators. The authors based their reconstruction of the weapon starting from the work of previous scientists and on their own translation of the original text (in ancient Greek) by Philon of Byzantium

How toxic are gold nanoparticles? The state-of-the-art.

With the growing interest in biotechnological applications of gold nanoparticles and their effects exerted on the body, the possible toxicity is becoming an increasingly important issue. Numerous investigations carried out, in the last few years, under different experimental conditions, following different protocols, have produced in part conflicting results which have leaded to different views about the effective gold nanoparticle safety in human applications. This work is intended to provide an overview on the most recent experimental results in order to summarize the current state-of-the-art. However, rather than to present a comprehensive review of the available literature in this field, that, among other things, is really huge, we have selected some representative examples of both in vivo and in vitro investigations, with the aim of offering a scenario from which clearly emerges the need of an urgent and impelling standardization of the experimental protocols. To date, despite the great potential, the safety of gold nanoparticles is highly controversial and important concerns have been raised with the need to be properly addressed. Factors such as shape, size, surface charge, surface coating and surface functionalization are expected to influence interactions with biological systems at different extents, with different outcomes, as far as gold nanoparticle potentiality in biomedical applications is concerned. Moreover, despite the continuous attempt to establish a correlation between structure and interactions with biological systems, we are still far from assessing the toxicological profile of gold nanoparticles in an unquestionable manner. This review is intended to provide a contribution in this direction, offering some suggestions in order to reach the systematization of data over the most relevant physico-chemical parameters, which govern and control toxicity, at different cellular and organismal levels

Chemiresistive polyaniline-based gas sensors: a mini review

This review focuses on some recent advances made in the field of gas sensors based on polyaniline [PANI], a conducting polymer with excellent electronic conductivity and electrochemical properties. Conducting polymers represent an important class of organic materials with an enhanced resistivity towards external stimuli. Among them, PANI polymers have attracted wide interest because of the versatility in their use, combined with the easy of synthesis, high yield and good environmental stability, together with a favorable response to guest molecules at room temperature. Moreover, PANI can be shaped into various structures with different morphologies and the possibility of obtaining nanofibers, in addition to thin films, has opened a rapid development of ultrasensitive chemical sensors, with improved processability and functionality. This review provides a brief description of the current status of gas chemiresistive sensors based on polyaniline and highlights the properties and applications of these devices in diverse range of applications. © 2015 Elsevier B.V. All rights reserved

Palmitoylethanolamide is a disease-modifying agent in peripheral neuropathy : pain relief and neuroprotection share a PPAR-alpha-mediated mechanism

Peer reviewedPublisher PD

Application of Buckingham π theorem for scaling-up oriented fast modelling of Proton Exchange Membrane Fuel Cell impedance

Abstract This work focuses on the development of a fast PEMFC impedance model, built starting from both physical and geometrical variables. Buckingham's π theorem is proposed to define non-dimensional parameters that allow suitably describing the relationships linking the physical variables involved in the process under-study to the fundamental dimensions. This approach is a useful solution for those problems, whose first principles-based models are not known, difficult to build or computationally unfeasible. The key contributions of the proposed similarity theory-based modelling approach are presented and discussed. The major advantage resides in its straightforward online applicability, thanks to very low computational burden, while preserving good level of accuracy. This makes the model suitable for several purposes, such as design, control, diagnostics, state of health monitoring and prognostics. Experimental data, collected in different operating conditions, have been analysed to demonstrate the capability of the model to reproduce PEMFC impedance at different loads and temperatures. This results in a reduction of the experimental effort for the FCS lab characterization. Moreover, it is highlighted the possibility to use the model with scaling-up purposes to reproduce the full stack impedance from single-cell one, thus supporting FC design and development from lab-to commercial system-scale

Core shell hybrids based on noble metal nanoparticles and conjugated polymers: synthesis and characterization

Noble metal nanoparticles of different sizes and shapes combined with conjugated functional polymers give rise to advanced core shell hybrids with interesting physical characteristics and potential applications in sensors or cancer therapy. In this paper, a versatile and facile synthesis of core shell systems based on noble metal nanoparticles (AuNPs, AgNPs, PtNPs), coated by copolymers belonging to the class of substituted polyacetylenes has been developed. The polymeric shells containing functionalities such as phenyl, ammonium, or thiol pending groups have been chosen in order to tune hydrophilic and hydrophobic properties and solubility of the target core shell hybrids. The Au, Ag, or Pt nanoparticles coated by poly(dimethylpropargylamonium chloride), or poly(phenylacetylene-co-allylmercaptan). The chemical structure of polymeric shell, size and size distribution and optical properties of hybrids have been assessed. The mean diameter of the metal core has been measured (about 10-30 nm) with polymeric shell of about 2 nm

Role of Endoscopy in Tracheo-esophageal Prosthesis Phonation. Technical and Psychological Aspects. Our Institutional Experience

In our study, we have analyzed the use of flexible video endoscopy in patients undergoing total laryngectomy and candidates for the placement of a voice prosthesis, with the creation of a tracheo-esophageal fistula in which the prosthesis is positioned, which acts as a valve one-way, which allows the passage of air from the trachea to the oesophagus and prevents the passage of liquids in the opposite direction, allowing the pulmonary air to vibrate a segment of the cervical oesophagus. The use of flexible video endoscopy for the positioning of the prosthesis can be both primary and secondary to the intervention of total laryngectomy. Endoscopy has also been used in the ontological follow-up for the assessment of the hypo pharyngeal-oesophageal-gastric district in the search for relapses or secondary tumors, which may develop in this district in more than 10% of patients with pathological neoplasia. Higher aero-digestiv

Nasal anomalies review with CT or MRI: from congenital to malignant.

Learning Objectives. To describe imaging findings of a wide spectrum of uncommon nasal cavity masses evaluated at our institution by CT, CBCT and MR imaging, clinically and pathologically proven. Background. In this work we present a succinct review of disease illustrated by a retrospective case series of nasalcavity masses, evaluated at our institution. between 2010 and 2013. Patients have been studied with different imaging modalities including multiraw computed tomography (CT), cone beam computed tomography (CBCT) and magnetic resonance imaging (MR) to illustrate the findings and to summarize the main diagnostic keypoints for the differential diagnosis of nasal masses. Clinicopathological correlation is also reported and imaging findings we present have been isthopathologically proven. Images aid in recognition and characterization of the lesions. Many different types of lesions may involve the nasal cavities and imaging studies, CBCT, CT and MR, provide anatomical details and could be helpful first in differentiating benign to malignant lesions and secondary in characterization of the lesion. Referring to non neoplastic lesions, rinoliths, piogenic granuloma and septal mucocele are reported. Referring to benign and borderline tumors osteoma, hamartoma, hemangioma, hemangiopericytoma, cemento-ossifying fibroma, antrochoanal polip and inverted papilloma are reported. Referring to malignant neoplasms intestinal type adenocarcinoma, esthesioneuroblastoma and Non-Hodgkin lymphoma are reported. CONCLUSION. This review of uncommon nasal masses studied with different imaging modalities (CT, CBCT and MRI)should be useful in differential diagnosis of the wide spectrum of nasal tumors and non tumors masses

BioEnterics Intragastric Balloon (BIB) versus Spatz Adjustable BalloonSystem (ABS): Our experience in the elderly

The BioEnterics Intragastric Balloon (BIB) and the Spatz Adjustable Balloon System (ABS) are in fact recommended for weight reduction as a bridge to bariatric surgery. We retrospected studied patients with body mass index (BMI) and age ranges of 37e46 and 70e80 years, respectively, who had undergone BIB from January 2010 to July 2012 and prospected studied patients who had undergone Spatz balloon from July 2012 to August 2014. The aim of this study is to compare BIB and Spatz in terms of weight loss, complications, and maintenance of weight after removal. For both procedures, the median weight loss was 20 ± 3 kg, median BMI at the end of the therapy was 32 ± 2, and no severe complication occurred

Pain Modulation in WAG/Rij Epileptic Rats (A Genetic Model of Absence Epilepsy): Effects of Biological and Pharmacological Histone Deacetylase Inhibitors

Epigenetic mechanisms are involved in epilepsy and chronic pain development. About that, we studied the effects of the natural histone deacetylase (HDAC) inhibitor sodium butyrate (BUT) in comparison with valproic acid (VPA) in a validated genetic model of generalized absence epilepsy and epileptogenesis. WAG/Rij rats were treated with BUT (30 mg/kg), VPA (300 mg/kg), and their combination (BUT + VPA) daily per os for 6 months. Rats were subjected at Randall-Selitto, von Frey, hot plate, and tail flick tests after 1, 3, and 6 months of treatment to evaluate hypersensitivity to noxious and non-noxiuous stimuli. Moreover, PPAR-γ (G3335 1 mg/kg), GABA-B (CGP35348 80 mg/kg), and opioid (naloxone 1 mg/kg) receptor antagonists were administrated to investigate the possible mechanisms involved in analgesic activity. The expression of NFkB, glutathione reductase, and protein oxidation (carbonylation) was also evaluated by Western blot analysis. WAG/Rij rats showed an altered pain threshold throughout the study (p < 0.001). BUT and BUT + VPA treatment reduced hypersensitivity (p < 0.01). VPA was significantly effective only after 1 month (p < 0.01). All the three receptors are involved in BUT + VPA effects (p < 0.001). BUT and BUT + VPA decreased the expression of NFkB and enhanced glutathione reductase (p < 0.01); protein oxidation (carbonylation) was reduced (p < 0.01). No effect was reported with VPA. In conclusion BUT, alone or in coadministration with VPA, is a valuable candidate for managing the epilepsy-related persistent pain