Surface and interfacial chemistry is of fundamental importance in functional nanomaterials applied in catalysis, energy storage and conversion, medicine, and other nanotechnologies. It has been a ...perpetual challenge for the scientific community to get an accurate and comprehensive picture of the structures, dynamics, and interactions at interfaces. Here, some recent examples in the major disciplines of nanomaterials are selected (e.g., nanoporous materials, battery materials, nanocrystals and quantum dots, supramolecular assemblies, drug‐delivery systems, ionomers, and graphite oxides) and it is shown how interfacial chemistry can be addressed through the perspective of solid‐state NMR characterization techniques.
Surface and interfacial chemistry is of fundamental importance in functional nanomaterials. It has been a perpetual challenge to get an accurate and comprehensive picture of structures, dynamics, and interactions. Through various recent examples in the major disciplines of nanomaterials, it is shown how interfacial chemistry can be addressed through the perspective of solid‐state NMR characterization techniques.
In the last decades, a variety of nuclear magnetic resonance (NMR) techniques have been applied with success in the field of advanced functional materials, including the important area of drug ...delivery. In such field, solid-state NMR (SSNMR) is an irreplaceable tool in the arsenal of characterization techniques, offering unique and comprehensive perspectives for the description of chemical structure, spatial connectivity and interfacial phenomena of solid dosage forms. This review focuses on the widespread applications of SSNMR in drug delivery field, an overview of selected case studies is provided, together with possible developments.
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In the last years, nanogels have emerged as one of the most promising classes of novel drug delivery vehicles since they can be employed in multiple fields, such as various therapeutics or ...diagnostics, and with different classes of compounds and active molecules. Their features, such as a high volume to surface ratio, excellent drug loading and release ability, as well as biocompatibility and tunable behavior, are unique, and, nowadays, great efforts are made to develop new formulations that can be employed in a wider range of applications. Polyethylene glycol (PEG)-polyethylenimine (PEI) nanogels probably represent the baseline of this class of biomaterials and they are still largely employed and studied. In any way, the possibility to exploit new core formulations for nanogels is certainly very interesting in order to understand the influence of different polymer chains on the final properties of the system. In this research, we explore and make a comparison between PEG-PEI nanogels and two other different formulations: pluronic F127-PEI nanogels and PEG-Jeffamine nanogels. We propose nanogels synthesis methods, their chemical and physical characterization, as well as their stability analysis, and we focus on the different drug delivery ability that these structures exhibit working with different typologies of drug mimetics.
We present the first high-quality catalog of early aftershocks of the three mainshocks of the 2016 central Italy Amatrice-Visso-Norcia normal faulting sequence. We located 10,574 manually picked ...aftershocks with a robust probabilistic, non-linear method achieving a significant improvement in the solution accuracy and magnitude completeness with respect to previous studies. Aftershock distribution and relocated mainshocks give insight into the complex architecture of major causative and subsidiary faults, thus providing crucial constraints on multi-segment rupture models. We document reactivation and kinematic inversion of a WNW-dipping listric structure, referable to the inherited Mts Sibillini Thrust (MST) that controlled segmentation of the causative normal faults. Spatial partitioning of aftershocks evidences that the MST lateral ramp had a dual control on rupture propagation, behaving as a barrier for the Amatrice and Visso mainshocks, and later as an asperity for the Norcia mainshock. We hypothesize that the Visso mainshock re-activated also the deep part of an optimally oriented preexisting thrust. Aftershock patterns reveal that the Amatrice Mw5.4 aftershock and the Norcia mainshock ruptured two distinct antithetic faults 3-4 km apart. Therefore, our results suggest to consider both the MST cross structure and the subsidiary antithetic fault in the finite-fault source modelling of the Norcia earthquake.
Narrow 1H NMR linewidths can be obtained for fully protonated protein samples in the solid state by using ultrafast magic‐angle spinning (60 kHz). Medium‐size microcrystalline and noncrystalline ...proteins can be analyzed without any need for deuteration of the protein sample. This approach provides assignments of the backbone 1H, 15N, 13Cα, and 13CO resonances and yields information about 1H–1H proximities.
Starting from late May 2012, the Emilia region (Northern Italy) was severely shaken by an intense seismic sequence, originated from a ML 5.9 earthquake on May 20th, at a hypocentral depth of 6.3km, ...with thrust-type focal mechanism. In the following days, the seismic rate remained high, counting 50 ML≥2.0 earthquakes a day, on average. Seismicity spreads along a 30km east–west elongated area, in the Po river alluvial plain, in the nearby of the cities Ferrara and Modena. Nine days after the first shock, another destructive thrust-type earthquake (ML 5.8) hit the area to the west, causing further damage and fatalities. Aftershocks following this second destructive event extended along the same east-westerly trend for further 20km to the west, thus illuminating an area of about 50km in length, on the whole. After the first shock struck, on May 20th, a dense network of temporary seismic stations, in addition to the permanent ones, was deployed in the meizoseismal area, leading to a sensible improvement of the earthquake monitoring capability there. A combined dataset, including three-component seismic waveforms recorded by both permanent and temporary stations, has been analyzed in order to obtain an appropriate 1-D velocity model for earthquake location in the study area. Here we describe the main seismological characteristics of this seismic sequence and, relying on refined earthquakes location, we make inferences on the geometry of the thrust system responsible for the two strongest shocks.
•First complete analysis of the 2012 Emilia mainshocks–aftershocks seismic sequence.•New catalog of the seismic sequence including data from temporary stations•Sensible improvement in terms of the activated fault system geometry definition•The different dip of the activated fault segments is highlighted and discussed.•Basic information are provided for further specific studies and hazard scenarios.
Porous hydroxyapatite (HA) matrices with high porosity were prepared through a high temperature sintering method by using HA powder as raw material, polystyrene (PS) microspheres as pore-forming ...agents and polyvinyl alcohol (PVA) solution as adhesive. The characterization of HA was carried out by a series of techniques including XRD, FT-IR, FESEM and BET, and showed that the morphology and structure of porous HA material were closely related to the amount of PS and PVA. The adsorption capability for Cu2+, Cd2+ and Pb2+ in aqueous solution showed that the porous HA possessed a selective and strong uptake of Pb2+ ions and the adsorption efficiency reached 99.8% in 10 min.
23Na is a nuclear magnetic resonance (NMR)-active isotope with a nuclear spin quantum number of 3/2. 23Na relaxation phenomenon is at the core of 23Na NMR measurement and analysis. Due to the ...dominance of quadrupolar interaction, the relaxation behavior of 23Na is physically and mathematically more complex than that of a typical spin-1/2 isotope. In this review, we overview the semi-classical Redfield theory for deriving the formulations of 23Na relaxation. We show that the relaxation behaviors of 23Na can be quantitatively described by constructing the spectral density functions based on the second-order perturbation theory. In addition, we summarize the applications of 23Na relaxometry in different research fields, including biomedicine, sodium ion batteries, and quantum information processing. Because sodium is an essential element in our body, food and industrial materials, the research on sodium by 23Na NMR emerges as important future directions. The theoretical and practical understandings on 23Na relaxation are the step stones for mastering advanced 23Na NMR techniques.
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Organic matter, an important component of healthy soils, may be used as an indicator in sustainability assessments. Managing soil carbon storage can foster agricultural productivity and environmental ...quality, reducing the severity and costs of natural phenomena. Thus, accurately estimating the spatial variability of soil organic matter (SOM) is crucial for sustainable soil management when planning agro-environmental measures at the regional level. SOM variability is very large in Italy, and soil organic carbon (SOC) surveys considering such variability are difficult and onerous. The study concerns the Abruzzo Region (about 10,800 km2), in Central Italy, where data from 1753 soil profiles were available, together with a Digital Elevation Model (DEM) and Landsat images. Some morphometric parameters and spectral indices with a significant degree of correlation with measured data were used as predictors for regression-kriging (RK) application. Estimated map of SOC stocks, and of SOM related to USDA (United States Department of Agriculture) texture—an additional indicator of soil quality—were produced with a satisfactory level of accuracy. Results showed that SOC stocks and SOM concentrations in relation to texture were lower in the hilly area along the shoreline, pointing out the need to improve soil management to guarantee agricultural land sustainability.
Type 1 diabetes mellitus (T1D) is a chronic disease that, if not treated properly, can lead to serious complications. We propose a layered meta-learning approach based on multi-expert systems to ...predict adverse events in T1D. The base learner is composed of three deep neural networks and exploits only continuous glucose monitoring data as an input feature. Each network specializes in predicting whether the patient is about to experience hypoglycemia, hyperglycemia, or euglycemia. The output of the experts is passed to a meta-learner to provide the final model classification. In addition, we formally introduce a novel parameter, <inline-formula> <tex-math notation="LaTeX">\alpha </tex-math></inline-formula>, to evaluate the advance by which a prediction is performed. We evaluate the proposed approach on both a public and a private dataset and implement it on an edge device to test its feasibility in real life. On average, on the Ohio T1DM dataset, our system was able to predict hypoglycemia events with a time gain of 22.8 minutes, hyperglycemia ones with an advance of 24.0 minutes. Our model not only outperforms presented models in the literature in terms of events predicted with sufficient advance, but also with regard to the number of false positives, achieving on average 0.45 and 0.46 hypo- and hyperglycemic false alarms per day, respectively. Furthermore, the meta-learning approach effectively improves performance in a new cohort of patients by training only the meta-learner with a limited amount of data. We believe our approach would be an essential ally for the patients to control the glycemic fluctuations and adjust their insulin therapy and dietary intakes, enabling them to speed up decision-making and improve personal self-management, resulting in a reduced risk of acute and chronic complications. As our last contribution, we assessed the validity of the approach by exploiting only blood glucose variations as well as in combination with the information of the insulin boluses, the skin temperature, and the galvanic skin response. In general, we have observed that providing other information but CGM leads to slightly lower performances with respect to considering CGM alone.
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