Does Size Matter? The Case of Piezoresistive Properties of Carbon Nanotubes/Elastomer Nanocomposite Synthesized through Mechanochemistry

The growing interest in piezoresistive sensors has favored the development of numerous approaches and materials for their fabrication. Within this framework, carbon nanotubes (CNTs) are often employed. However, CNTs are a heterogeneous material with different morphological characteristics in terms of length and diameter, and, so far, experimental studies have not usually considered the effect of these parameters on the final sensor performances. Here, we observe how, by simply changing the CNTs length in a solvent-free mechanochemistry fabrication method, different porous 3D elastomeric nanocomposites with different electrical and mechanical properties can be obtained. In particular, the use of longer carbon nanotubes allows the synthesis of porous nanocomposites with better mechanical stability and conductivity, and with a nine-times-lower limit of detection (namely 0.2 Pa) when used as a piezoresistive sensor. Moreover, the material prepared with longer carbon nanotubes evidenced a faster recovery of its shape and electrical properties during press/release cycles, thus allowing faster response at different pressures. These results provide evidence as to how CNTs length can be a key aspect in obtaining piezoresistive sensors with better properties

Validation of a lab-on-chip assay for measuring sorafenib effectiveness on hcc cell proliferation

Hepatocellular carcinoma (HCC) is a highly lethal cancer, and although a few drugs are available for treatment, therapeutic effectiveness is still unsatisfactory. New drugs are urgently needed for hepatocellular carcinoma (HCC) patients. In this context, reliable preclinical assays are of paramount importance to screen the effectiveness of new drugs and, in particular, measure their effects on HCC cell proliferation. However, cell proliferation measurement is a time-consuming and operator-dependent procedure. The aim of this study was to validate an engineered miniaturized on-chip platform for real-time, non-destructive cell proliferation assays and drug screening. The effectiveness of Sorafenib, the first-line drug mainly used for patients with advanced HCC, was tested in parallel, comparing the gold standard 96-well-plate assay and our new lab-on-chip platform. Results from the lab-on-chip are consistent in intra-assay replicates and comparable to the output of standard crystal violet proliferation assays for assessing Sorafenib effectiveness on HCC cell proliferation. The miniaturized platform presents several advantages in terms of lesser reagents consumption, operator time, and costs, as well as overcoming a number of technical and operator-dependent pitfalls. Moreover, the number of cells required is lower, a relevant issue when primary cell cultures are used. In conclusion, the availability of inexpensive on-chip assays can speed up drug development, especially by using patient-derived samples to take into account disease heterogeneity and patient-specific characteristics

Advances in Materials and Technologies for Gas Sensing from Environmental and Food Monitoring to Breath Analysis

Gas sensing research experiences a worldwide revival in the last years. From one side, the emergence of novel sensing materials enables unprecedented capacities for improving the device performances. From the other, the increasing opportunities for applications impacting current societal priorities highly motivate further studies. Here, this field is reviewed with special attention to the emerging approaches and the most recent breakthroughs, challenges, and perspectives. In particular, this study focuses on: 1) the sensing layers analyzing recent trends toward nanostructured, low-dimensional and composite materials; and 2) the latest achievements and targets in terms of applications, from environmental monitoring to food aroma identification and quality control up to the healthcare sector with breath analysis and diseases diagnosis

Performance of the diamond active target prototype for the PADME experiment at the DAΦ\PhiNE BTF

The PADME experiment at the DA$\Phi$NE Beam-Test Facility (BTF) is designed to search for the gauge boson of a new $\rm U(1)$ interaction in the process e$^+$e$^-\rightarrow\gamma$+$\rm A'$, using the intense positron beam hitting a light target. The $\rm A'$, usually referred as dark photon, is assumed to decay into invisible particles of a secluded sector and it can be observed by searching for an anomalous peak in the spectrum of the missing mass measured in events with a single photon in the final state. The measurement requires the determination of the 4-momentum of the recoil photon, performed by a homogeneous, highly segmented BGO crystals calorimeter. A significant improvement of the missing mass resolution is possible using an active target capable to determine the average position of the positron bunch with a resolution of less than 1 mm. This report presents the performance of a real size $\rm (2x2 cm^2)$ PADME active target made of a thin (50 $\mu$m) diamond sensor, with graphitic strips produced via laser irradiation on both sides. The measurements are based on data collected in a beam test at the BTF in November 2015.Comment: 7 pages, 10 figure

Polydopamine-Coated Magnetic Iron Oxide Nanoparticles: From Design to Applications

Magnetic iron oxide nanoparticles have been extensively investigated due to their applications in various fields such as biomedicine, sensing, and environmental remediation. However, they need to be coated with a suitable material in order to make them biocompatible and to add new functionalities on their surface. This review is intended to give a comprehensive overview of recent advantages and applications of iron oxide nanoparticles coated by polydopamine film. The synthesis method of magnetic nanoparticles, their functionalization with bioinspired materials and (in particular) with polydopamine are discussed. Finally, some interesting applications of polydopamine-coated magnetic iron oxide nanoparticles will be pointed out

Effect of surface tension and drying time on inkjet-printed PEDOT:PSS for ITO-free OLED devices

Abstract Highly conductive PEDOT:PSS is one of the most promising materials for indium tin oxide (ITO) substitution in printed electronics. Here, we report the development and optimisation of two PEDOT:PSS ink formulations for the fabrication of inkjet-printed transparent conductive layers. Starting from aqueous commercial solutions, co-solvents and a non-ionic surfactant were employed to modify the surface tension, improve the wetting capability of the ink, and obtain uniform and homogeneous thin films. In particular, the quantities of ethanol and surfactant were systematically adjusted to determine the optimal conditions for inkjet printing. The results demonstrate that a surface tension value between 28 and 40 mN/m and approximately 40 vol.% of a low-boiling-point co-solvent are fundamental to ensure the proper wetting of the glass substrate and a quick-drying process that confers uniformity to the printed thin film. The printed PEDOT:PSS thin films show good morphological, optical, and electrical properties that are similar to those observed for the corresponding spin-coated layers. The organic light-emitting diodes (OLEDs) fabricated with the inkjet-printed PEDOT:PSS electrodes showed a maximum quantum efficiency of 5.5% and maximum current efficiency of 15 cd/A, which is comparable to spin-coated reference devices. These results demonstrate the great potential of polymeric electrodes for the fabrication of high-efficiency printed OLED devices that are compatible with flexible and stretchable substrates

Nuovi indicatori bibliometrici nella letteratura scientifica: un panorama in continua evoluzione

Introduzione. La bibliometria è una scienza che utilizza metodi matematici e statistici per valutare l’impatto della produzione scientifica di una rivista o di un singolo ricercatore. Il primo indicatore bibliometrico ad essere stato ideato è stato l’Impact Factor (IF), a cui successivamente se ne sono affiancati di nuovi, volti a superarne i limiti. Attualmente gli indicatori bibliometrici vengono utilizzati a scopi accademici, anche per valutare l’idoneità di uno studioso a concorrere per l’Abilitazione Scientifica Nazionale per poter accedere ai concorsi per docente. Obiettivo. Scopo di questo lavoro è stato quello di individuare i principali indicatori di impatto e di riassumerne le caratteristiche. Metodi. È stata condotta una revisione degli indicatori bibliometrici, partendo da quelli classici e terminando a quelli di più recente introduzione. Risultati. I due indicatori bibliometrici più usati sono l’IF, che misura l’impatto scientifico di una rivista e si basa sul database citazionale Web of Science, e l’h-index, che invece misura l’impatto del lavoro scientifico di un ricercatore e si basa sul database Scopus. Accanto a questi ne sono stati ideati altri più recentemente tra cui lo SCImago Journal Rank Indicator (SJR), il Source Normalised Impact per Paper (SNIP) e il Citescore index, che si basano tutti sul database citazionale Scopus, e che valutano, in modi diversi, l’impatto citazionale di una rivista. L’i10-index invece viene fornito dal database Google Scholar e permette di valutare l’impatto della produzione scientifica di un ricercatore. Di recente introduzione sono anche due software: il primo, Publish or Perish, permette, attraverso il calcolo di numerosi indici, la valutazione dell’impatto del lavoro scientifico di un ricercatore; il secondo, Altmetric, tramite l’uso di metriche alternative ai tradizionali indicatori, permette di misurare l’utilizzo delle pubblicazioni accademiche, piuttosto che le citazioni, nel Web. Conclusioni. Ciascun indicatore analizzato presenta dei vantaggi e delle criticità. Per tale motivo sarebbe auspicabile un utilizzo integrato di più metriche, sia di tipo citazionale che non, in modo da valutare correttamente il lavoro dei ricercatori e migliorare la qualità e lo sviluppo della ricerca scientificaIntroduction. Bibliometrics is a science which evaluates the impact of the scientific work of a journal or of an author, using mathematical and statistical tools. Impact Factor (IF) is the first bibliometric parameter created, and after it many others have been progressively conceived in order to go beyond its limits. Currently bibliometric indexes are used for academic purposes, among them to evaluate the eligibility of a researcher to compete for the National Scientific Qualification, in order to access to competitive exams to become professor. Objective. Aim of this study is to identify the most relevant bibliometric indexes and to summarized their characteristics. Methods. A revision of bibliometric indexes as been conducted, starting from the classic ones and completing with the most recent ones. Results. The two most used bibliometric indexes are the IF, which measures the scientific impact of a periodical and bases on Web of Science citation database, and the h-index, which measures the impact of the scientific work of a researcher, basing on Scopus database. Besides them other indexes have been created more recently, such as the SCImago Journal Rank Indicator (SJR), the Source Normalised Impact per Paper (SNIP) and the CiteScore index. They are all based on Scopus database and evaluate, in different ways, the citational impact of a periodic. The i10-index instead is provided from Google Scholar database and allows to evaluate the impact of the scientific production of a researcher. Recently two softwares have been introduced: the first one, Publish or Perish, allows to evaluate the scientific work of a researcher, through the assessment of many indexes; the second one, Altmetric, measure the use in the Web of the academic papers, instead of measuring citations, by means of alternative metrics respect to the traditional ones. Conclusions. Each analized index shows advantages but also criticalities. Therefore the combined use of more than one indexes, citational and not, should be preferred, in order to correctly evaluate the work of reserchers and to finally improve the quality and the development of scientific research

Study of a metal-halide perovskite CsPbBr3 thin film deposited on a 10B layer for neutron detection

Metal halide perovskite materials have received significant attention in recent years due to their promising properties and potential applications, particularly their use as scintillator detectors, which is rapidly emerging due to their promising advantages as detectors, such as low costs, fast response, high quantum yield, strong absorption, scalability, flexibility, and emission wavelength tunability. Given the effectiveness of perovskites as α particle detectors and the potential of 10B as a neutron converter, in this paper a 10B converting layer was coupled with an all-inorganic lead halide perovskite (CsPbBr3) layer aiming to create a thermal neutron detector. Specifically, a 1 μm thin film of 10B and a 1 μm thin layer of CsPbBr3 were deposited on a suitable substrate using a laser ablation process. The fabricated detector was subjected to a comprehensive characterization, including structural, morphological, and detection properties. As output, the films exhibit macroscopically uniform behavior and good adhesion to the substrate. In terms of thermal neutron efficiency, an efficiency of (7.9 ± 0.3)% was determined with respect to a commercial detector (EJ-426), which corresponds to an intrinsic efficiency of (2.5 ± 0.1)%. Also, Monte Carlo simulations were conducted, and the optimum value of the 10B layer thickness was found to be 2.5 μm

The Encapsulation of Citicoline within Solid Lipid Nanoparticles Enhances Its Capability to Counteract the 6-Hydroxydopamine-Induced Cytotoxicity in Human Neuroblastoma SH-SY5Y Cells

(1) Backgrond: Considering the positive effects of citicoline (CIT) in the management of some neurodegenerative diseases, the aim of this work was to develop CIT-Loaded Solid Lipid Nanoparticles (CIT-SLNs) for enhancing the therapeutic use of CIT in parkinsonian syndrome; (2) Methods: CIT-SLNs were prepared by the melt homogenization method using the self-emulsifying lipid Gelucire® 50/13 as lipid matrix. Solid-state features on CIT-SLNs were obtained with FT-IR, thermal analysis (DSC) and X-ray powder diffraction (XRPD) studies. (3) Results: CIT-SLNs showed a mean diameter of 201 nm, −2.20 mV as zeta potential and a high percentage of entrapped CIT. DSC and XRPD analyses evidenced a greater amorphous state of CIT in CIT-SLNs. On confocal microscopy, fluorescent SLNs replacing unlabeled CIT-SLNs released the dye selectively in the cytoplasm. Biological evaluation showed that pre-treatment of SH-SY5Y dopaminergic cells with CIT-SLNs (50 µM) before the addition of 40 µM 6-hydroxydopamine (6-OHDA) to mimic Parkinson’s disease’s degenerative pathways counteracts the cytotoxic effects induced by the neurotoxin, increasing cell viability with the consistent maintenance of both nuclear and cell morphology. In contrast, pre-treatment with CIT 50 and 60 µM or plain SLNs for 2 h followed by 6-OHDA (40 µM) did not significantly influence cell viability. (4) Conclusions: These data suggest an enhanced protection exerted by CIT-SLNs with respect to free CIT and prompt further investigation of possible molecular mechanisms that underlie this difference

Long lasting octreotide LAR therapy in non functioning pancreatic neuroendocrine carcinoma

Non functioning endocrine pancreatic tumors (NF-PETs) have absent or low hormone secretion without symptoms and constitue ~60% of PETs. At diagnosis more than 50% of patients have liver metastases and almost 40% are not candidates for radical surgery because of either locally advanced disease or unresectable metastases. We described the case of a 47-year-old woman with a pancreatic carcinoma with secondarism in the liver not suitable for radical surgery. Histological test of liver metastases showed positivity for endocrine well-differentiated non functioning carcinoma expressing receptors for somatostatin with very low proliferation index (Ki67 < 2%). After this diagnosis she started a specific treatment with octreotide analogues which achieved durable stabilization of the disease