Reusable Cavitand-Based Electrospun Membranes for the Removal of Polycyclic Aromatic Hydrocarbons from Water

The removal of toxic and carcinogenic polycyclic aromatic hydrocarbons (PAHs) from water is one of the most intractable environmental problems nowadays, because of their resistance to remediation. This work introduces a highly efficient, regenerable membrane for the removal of PAHs from water, featuring excellent filter performance and pH-driven release, thanks to the integration of a cavitand receptor in electrospun polyacrylonitrile (PAN) fibers. The role of the cavitand receptor is to act as molecular gripper for the uptake/release of PAHs. To this purpose, the deep cavity cavitand BenzoQxCav is designed and synthetized and its molecular structure is elucidated via X-Ray diffraction. The removal efficiency of the new adsorbent material toward the 16 priority PAHs is demonstrated via GC-MS analyses at ng L^?1 concentration. A removal efficiency in the 32%, to 99% range is obtained. The regeneration of the membrane is performed by exploiting the pH-driven conformational switching of the cavitand between the vase form, where the PAHs uptake takes place, to the kite one, where the PAHs release occurs. The absorbance and regeneration capability of the membrane are successfully tested in four uptake/release cycles and the morphological stability.     

An automated procedure to properly handle digital images in large scale tissue microarray experiments

Tissue Microarray (TMA) methodology has been recently developed to enable "genome-scale" molecular pathology studies. To enable high-throughput screening of TMAs automation is mandatory, both to speed up the process and to improve data quality. In particular, in acquiring digital images of single tissues (core sections) a crucial step is the correct recognition of each tissue position in the array. In fact, further reliable data analysis is based on the exact assignment of each tissue to the corresponding tumor. As most of the times tissue alignment in the microarray grid is far from being perfect, simple strategies to perform proper acquisition do not fit well. The present paper describes a new solution to automatically perform grid location assignment. We developed an ad hoc image processing procedure and a robust algorithm for object recognition. Algorithm accuracy tests and assessment of working constraints are discussed. Our approach speeds up TMA data collection and enables large scale investigation.     

Electric current effect during the early stages of field-assisted sintering

The linear shrinkage during isothermal treatment in the early stages of conventional and field-assisted sintering of 8YSZ was analyzed. The results reveal that the application of a moderate electric current causes a remarkable acceleration of the self-diffusion kinetics, resulting in an enhanced densification. In addition, when an electric current is applied, two different field-assisted sintering regimes can be identified. The first one, observed at low currents (ie 5 mA/mm²), is associated to sintering shrinkage which follows the conventional trend () although the densification is accelerated. The second regime takes place when larger current are applied (J > 10 mA/mm²) and is described by a different sintering law, , this pointing out that the electric current causes the activation of alternative densification mechanisms when it exceeds a certain threshold value.     

An Increase in Membrane Cholesterol by Graphene Oxide Disrupts Calcium Homeostasis in Primary Astrocytes

The use of graphene nanomaterials (GNMs) for biomedical applications targeted to the central nervous system is exponentially increasing, although precise information on their effects on brain cells is lacking. In this work, the molecular changes induced in cortical astrocytes by few‐layer graphene (FLG) and graphene oxide (GO) flakes are addressed. The results show that exposure to FLG/GO does not affect cell viability or proliferation. However, proteomic and lipidomic analyses unveil alterations in several cellular processes, including intracellular Ca²⁺ ([Ca²⁺]_i) homeostasis and cholesterol metabolism, which are particularly intense in cells exposed to GO. Indeed, GO exposure impairs spontaneous and evoked astrocyte [Ca²⁺]_i signals and induces a marked increase in membrane cholesterol levels. Importantly, cholesterol depletion fully rescues [Ca²⁺]_i dynamics in GO‐treated cells, indicating a causal relationship between these GO‐mediated effects. The results indicate that exposure to GNMs alters intracellular signaling in astrocytes and may impact astrocyte–neuron interactions.     

Designing secure business processes with SecBPMN

Modern information systems are increasingly large and consist of an interplay of technical components and social actors (humans and organizations). Such interplay threatens the security of the overall system and calls for verification techniques that enable determining compliance with security policies. Existing verification frameworks either have a limited expressiveness that inhibits the specification of real-world requirements or rely on formal languages that are difficult to use for most analysts. In this paper, we overcome the limitations of existing approaches by presenting the SecBPMN framework. Our proposal includes: (1) the SecBPMN-ml modeling language, a security-oriented extension of BPMN for specifying composite information systems; (2) the SecBPMN-Q query language for representing security policies; and (3) a query engine that enables checking SecBPMN-Q policies against SecBPMN-ml specifications. We evaluate our approach by studying its understandability and perceived complexity with experts, running scalability analysis of the query engine, and through an application to a large case study concerning air traffic management.     

Potential natural polymer-based nanofibres for the development of facemasks in countering viral outbreaks

The global coronavirus disease 2019 (COVID-19) pandemic has rapidly increased the demand for facemasks as a measure to reduce the rapid spread of the pathogen. Throughout the pandemic, some countries such as Italy had a monthly demand of ca. 90 million facemasks. Domestic mask manufacturers are capable of manufacturing 8 million masks each week, although the demand was 40 million per week during March 2020. This dramatic increase has contributed to a spike in the generation of facemask waste. Facemasks are often manufactured with synthetic materials that are non-biodegradable, and their increased usage and improper disposal are raising environmental concerns. Consequently, there is a strong interest for developing biodegradable facemasks made with for example, renewable nanofibres. A range of natural polymer-based nanofibres has been studied for their potential to be used in air filter applications. This review article examines potential natural polymer-based nanofibres along with their filtration and antimicrobial capabilities for developing biodegradable facemask that will promote a cleaner production.     

Explaining high flow rate of water in carbon nanotubes via solid–liquid molecular interactions

Experimental and simulation measurements of water flow through carbon nanotubes have shown orders of magnitude higher flow rates than what was predicted using continuum fluid mechanics models. Different explanations have been offered, from slippage of water on the hydrophobic surface of the nanotubes to size confinement effects. In this work a model capable of explaining these observations, linking the enhanced flow rates observed to the solid?Cliquid molecular interactions at the nanotube wall is proposed. The model is capable of separating the effects on flow enhancement of the tube characteristic dimensions and the solid?Cliquid molecular interactions, accurately predicting the effect of each component for nanotubes of different sizes, wall surface chemistry and structure. Comparison with the experimental data available shows good agreement.     

Novel P2X7 Antagonist Ameliorates the Early Phase of ALS Disease and Decreases Inflammation and Autophagy in SOD1-G93A Mouse Model

Amyotrophic lateral sclerosis (ALS) is a disease with a resilient neuroinflammatory component caused by activated microglia and infiltrated immune cells. How to successfully balance neuroprotective versus neurotoxic actions through the use of anti-inflammatory agents is still under debate. There has been a boost of awareness regarding the role of extracellular ATP and purinergic receptors in modulating the physiological and pathological mechanisms in the nervous system. Particularly in ALS, it is known that the purinergic ionotropic P2X7 receptor plays a dual role in disease progression by acting at different cellular and molecular levels. In this context, we previously demonstrated that the P2X7 receptor antagonist, brilliant blue G, reduces neuroinflammation and ameliorates some of the pathological features of ALS in the SOD1-G93A mouse model. Here, we test the novel, noncommercially available, and centrally permeant Axxam proprietary P2X7 antagonist, AXX71, in SOD1-G93A mice, by assessing some behavioral and molecular parameters, among which are disease progression, survival, gliosis, and motor neuron wealth. We demonstrate that AXX71 affects the early symptomatic phase of the disease by reducing microglia-related proinflammatory markers and autophagy without affecting the anti-inflammatory markers or motor neuron survival. Our results suggest that P2X7 modulation can be further investigated as a therapeutic strategy in preclinical studies, and exploited in ALS clinical trials.