Generalized energy equipartition in harmonic oscillators driven by active baths

We study experimentally and numerically the dynamics of colloidal beads confined by a harmonic potential in a bath of swimming E. coli bacteria. The resulting dynamics is well approximated by a Langevin equation for an overdamped oscillator driven by the combination of a white thermal noise and an exponentially correlated active noise. This scenario leads to a simple generalization of the equipartition theorem resulting in the coexistence of two different effective temperatures that govern dynamics along the flat and the curved directions in the potential landscape.Comment: 4 pages, 3 figure

Monoethanolamine-Based Fuels Hypergolic with Rocket-Grade Hydrogen Peroxide

The object of this work is to study the ignition performances of promising catalytically promoted amino-based green fuels to be used in combination with rocket-grade hydrogen peroxide. The main hypergolic parameter, the ignition delay time, was experimentally determined with an automated drop test setup. Additionally, the kinematic viscosity was experimentally measured, while the CEA2 software was used to determine the ideal rocket performances of the propellants. Three inorganic copper salts were selected as catalysts to be used in combination with monoethanolamine in concentrations ranging from 0.5 wt% to 20 wt%. Then, N,N-dimethylethylenediamine was introduced as part of a blend with monoethanolamine to target the high viscosity and low gravimetric specific impulse of the fuel for the pure monoethanolamine case. Due to the reduced monoethanolamine and low additive content, some formulations were observed to be characterized by gravimetric specific impulse higher than 320 s, and kinematic viscosity lower than 5 cSt while retaining ignition delay times shorter than 30 ms with 98 wt% HTP. Finally, the addition of ethanol to the blend was preliminarily investigated to improve the additive solubility. The effects on the ignition delay time were found to depend on the concentration ratio of the two amines

Magnetic resonance imaging of experimental autoimmune encephalomyelitis in the common marmoset.

Magnetic resonance imaging (MRI) is an invaluable tool for the diagnosis and monitoring of patients with multiple sclerosis (MS) as well as for the study of the disease pathophysiology. Because of its strong clinical, radiological and histopathological similarities with the human disease, experimental autoimmune encephalomyelitis (EAE) in the common marmoset has been studied more intensively over the past several years. Here, we review the current knowledge on MRI in the marmoset EAE, and we outline the physiopathological significance and translational values of these studies with respect to MS. Accumulating evidences suggest that the application of conventional, as well as non-conventional, MRI techniques in the marmoset EAE is a promising approach to elucidate the pathological processes underlying the development of inflammatory demyelinated lesions in the central nervous system, potentially improving the identification and development of new therapeutics

Utilizzo delle vaccinazioni in pazienti con malattie autoimmuni sistemiche: analisi di una coorte di pazienti

Il lupus eritematoso sistemico (LES) è una malattia infiammatoria cronica, a patogenesi autoimmunitaria, con interessamento multisistemico e quadro clinico estremamente variabile. La sopravvivenza dei pazienti affetti da LES negli Stati Uniti e in Europa è, approssimativamente, del 95% a 5 anni, del 90% a 10 anni e del 78% a 20 anni. Le infezioni sono riconosciute come una delle cause principali di mortalità e di morbidità in tali pazienti. La vaccinazione rappresenta un’efficace strategia per la prevenzione di alcune malattie infettive anche in pazienti con LES; in particolare le vaccinazioni contro virus influenzale e Pneumococco si sono dimostrate sicure in tali pazienti e capaci di garantire un effetto protettivo. Raccomandazioni internazionali, infatti, supportano l’utilizzo di tali vaccini nei pazienti con LES. D’altro lato, i dati riguardanti la sicurezza e l’efficacia di altri vaccini sono più scarsi e frammentari. Nel corso degli anni 2015-2016 è stato registrato in Toscana un numero inaspettatamente elevato di casi di meningite C. Ne è derivata una campagna di sensibilizzazione diffusa su tutto il territorio regionale e l’attivazione di un programma di vaccinazioni per le categorie a rischio. Lo scopo principale di questo studio è quello di valutare l’aderenza alle raccomandazioni sulla vaccinazione anti-influenzale e anti-meningococco C in una coorte di pazienti affetti da malattie autoimmuni sistemiche. Con questo obiettivo è stato effettuato uno studio trasversale monocentrico in cui sono stati arruolati pazienti consecutivi afferenti al nostro centro con diagnosi di LES; come gruppo di controllo sono stati arruolati pazienti seguiti per altre malattie autoimmuni sistemiche (Artrite Reumatoide, Sindrome di Sjögren, Sclerosi Sistemica). L’obiettivo secondario è quello di valutare l’incidenza di eventi avversi nei pazienti che si sono sottoposti ad una o ad entrambe le vaccinazioni. Questa indagine è stata realizzata mediante la somministrazione di un questionario creato ad hoc. Dallo studio è emerso che nella popolazione in oggetto l’aderenza alle raccomandazioni sulle vaccinazioni è bassa per quanto concerne la vaccinazione antinfluenzale; è stato anche riscontrato un basso tasso di adesione alla campagna di vaccinazione anti-meningococco C. E’ emerso inoltre che i vaccini in analisi hanno un alto profilo di sicurezza, dato che pazienti che hanno effettuato tali vaccinazioni non hanno avuto nessuna riacutizzazione della malattia e solo alcuni hanno riferito qualche sintomo avverso aspecifico quali febbre e malessere

Therapeutic management of complicated talar extrusion: literature review and case report

Total extrusion of the talus with interruption of all ligaments (missing talus) is a rare injury. We describe the case of a 27-year-old man who reported total extrusion of the talus after a motorbike accident with interruption of all talar ligaments. In the first repair effort, the articular void left by the talus was filled with antibiotic cement and the wound was closed primarily. Nevertheless, the skin overlying the talar joint displayed necrosis. In order to cover the cutaneous defect, improve local vascularization, and allow reimplantation of the talus, a sural fasciocutaneous island flap was harvested. Subsequently, the original talus was placed and arthrodesis of the subtalar joint was performed. The patient was able to walk bearing full weight without support equipment after 6 months. Several therapeutic options have been suggested in such cases, including replacing the talus, tibiocalcaneal arthrodesis, and pseudoarthrodesis. The rarity and peculiarity of such cases make the establishment of generalized guidelines an arduous task, leaving the choice of treatment to the surgeon, in conformity with each case’s peculiarity. In this case use of the flap may have promoted the vascularization of the reimplanted talus, thus avoiding avascular necrosis and allowing successful reimplantation of the original talus

A Robust and Self-Paced BCI System Based on a Four Class SSVEP Paradigm: Algorithms and Protocols for a High-Transfer-Rate Direct Brain Communication

In this paper, we present, with particular focus on the adopted processing and identification chain and protocol-related solutions, a whole self-paced brain-computer interface system based on a 4-class steady-state visual evoked potentials (SSVEPs) paradigm. The proposed system incorporates an automated spatial filtering technique centred on the common spatial patterns (CSPs) method, an autoscaled and effective signal features extraction which is used for providing an unsupervised biofeedback, and a robust self-paced classifier based on the discriminant analysis theory. The adopted operating protocol is structured in a screening, training, and testing phase aimed at collecting user-specific information regarding best stimulation frequencies, optimal sources identification, and overall system processing chain calibration in only a few minutes. The system, validated on 11 healthy/pathologic subjects, has proven to be reliable in terms of achievable communication speed (up to 70 bit/min) and very robust to false positive identifications

Triage of IoT Attacks Through Process Mining

The impressive growth of the IoT we witnessed in the recent years came together with a surge in cyber attacks that target it. Factories adhering to digital transformation programs are quickly adopting the IoT paradigm and are thus increasingly exposed to a large number of cyber threats that need to be detected, analyzed and appropriately mitigated. In this scenario, a common approach that is used in large organizations is to setup an attack triage system. In this setting, security operators can cherry-pick new attack patterns requiring further in-depth investigation from a mass of known attacks that can be managed automatically. In this paper, we propose an attack triage system that helps operators to quickly identify attacks with unknown behaviors, and later analyze them in detail. The novelty introduced by our solution is in the usage of process mining techniques to model known attacks and identify new variants. We demonstrate the feasibility of our approach through an evaluation based on three well-known IoT botnets, BASHLITE, LIGHTAIDRA and MIRAI, and on real current attack patterns collected through an IoT honeypot

Experimental investigation of paraffin-based fuels for hybrid rocket propulsion

Solid fuels for hybrid rockets were characterized in the framework of a research project aimed to develop a new generation of solid fuels, combining at the same time good mechanical and ballistic properties. Original techniques were implemented in order to improve paraffin-based fuels. The first strengthening technique involves the use of a polyurethane foam (PUF); a second technique is based on thermoplastic polymers mixed at molecular level with the paraffin binder. A ballistic characterization of paraffin-based hybrid rocket solid fuels was performed, considering pure wax-based fuels and fuels doped with suitable metal additives. Nano-Al powders and metal hydrides (magnesium hydride (MgH2), lithium aluminum hydride (LiAlH4 )) were used as fillers in paraffin matrices. The results of this investigation show a strong correlation between the measured viscosity of the melted paraffin layer and the regression rate: a decrease of viscosity increases the regression rate. This trend is due to the increasing development of entrainment phenomena, which strongly increase the regression rate. Addition of LiAlH4 (mass fraction 10%) can further increase the regression rate up to 378% with respect to the pure HTPB regression rate, taken as baseline reference fuel. The highest regression rates were found for the Solid Wax (SW) composition, added with 5% MgH2 mass fraction; at 350 kg/(m2s) oxygen mass flux, the measured regression rate, averaged in space and time, was 2.5 mm/s, which is approximately five times higher than that of the pure HTPB composition. Compositions added with nanosized aluminum powders were compared with those added with MgH2, using gel or solid wax