In-situ monitoring of defects in extrusion-based bioprinting processes using visible light imaging

Tissue engineering techniques are central for the development of biomedical scaffolds, which are primarily employed in the biofabrication of various artificial human tissue and organ models. Bioprinting is a new technique of creating tissue constructs that can sustain cell proliferation. The development of printing techniques proceeds together with the development of the biomaterials to be printed, which is why studying the printability of these specific biomaterials must be explored. An appropriate hydrogel used as bioink should have numerous rheological, mechanical, and biological properties for producing appropriate tissue constructs. However, reaching the right trade-off between a desirable bioactivity and high printability is challenging, and despite numerous optimization studies for different materials, printing defects often occur during printing. Herein, methods are proposed to automatically identify these drifting processes in commonly used geometries and how they affected subsequent layers, as well as printing defects within each layer. Several structures were printed with standard commercial bioink as proof of concept. The constructs were analyzed using optical images from a coaxial camera. The images were then digitally processed to get geometrical data from which patterns of defectology to be monitored were derived. This automation should decrease the time in post-processing characterization of constructs and should provide a standardized tool to compare different bioinks

Empathy, Social Self-Efficacy, Problematic Internet Use, and Problematic Online Gaming Between Early and Late Adolescence

This study aims to investigate the relationship between empathy, social self-efficacy, problematic Internet use (PIU), and problematic online gaming (POG) and to evaluate how such relationship varies according to the age of the participants. A sample of 1,585 Italian students, both genders, aged 12-20 years, were divided into three groups according to the age filled in these self-report questionnaires: PIU; Game Addiction Scale for Adolescents; Interpersonal Reactivity Index; Scale of Social Self-Efficacy; Strengths and Difficulties Questionnaire. The results allow to confirm that in the Italian context the relationships between the examined constructs change across the three age groups considered in the study. PIU and POG, as well as prosocial behaviors and personal distress, tend to significantly decrease in late adolescence (age 18-20 years); 15-17 years adolescents reported more empathic concern compared with the other groups. PIU and POG are affected by empathy and social-self efficacy in different ways depending on age, suggesting that the two conditions have an at least partially different nature. The different components of empathy seem to play a different role in the development of either PIU or POG confirming the need to separate the components of empathy.Peer reviewe

Hydrogen chemoresistive sensor for the analysis of gut health

Hydrogen is a target gas in the assessment of gut health. Several are the approaches to estimate the concentration of this gas, endogenously present in the gut and, of course, in the blood and the exhaled breath. In this paper, development and characterization of a resistive gas sensor for hydrogen monitoring is reported. The sensing material is based on Nb2O5 Pt thin films, obtained by depositing a niobium oxide layer and a platinum one on a tiny alumina substrate, by means of a lab-scale plasma sputtering reactor. The deposited layers were treated with a thermal process at 600 °C for 30 min. The developed devices were characterized in a hydrogen concentration range of 2000 ppm to 80000 ppm, showing promising results

A Movement-Tremors Recorder for Patients of Neurodegenerative Diseases

Neurodegenerative diseases such as Alzheimer, Parkinson, motor neuron, and Chorea affect millions of people today. Their effect on the central nervous system causes the loss of brain functions as well as motor disturbances and sometimes cognitive deficits. In such a scenario, the monitoring and evaluation of early symptoms are mandatory for the improvement of the patient's quality of life. Here, the authors describe the development, the laboratory calibration, and the "in-field validation" under the medical supervision of a movement tremors recorder for subjects affected by neurodegenerative diseases. The developed device is based on an array of four accelerometers connected to an embedded development board. This system is able to monitor tremor/movement, accidental falls, and, moreover, it can track the Alzheimer subjects' geographical position. A remote supervisor can collect data from the system through Bluetooth, Wi-Fi, or GSM connections. A data compression algorithm was developed directly on board in order to increase the efficiency of data transmission and reduce power consumptions

Fiber-reinforced lightweight foamed concrete panels suitable for 3D printing applications

This contribution presents a set of experimental results on fiber-reinforced innovative lightweight panels (FRIL-panels) having thickness of 12mm. These panels are prepared with a peculiar foamed concrete that has a high viscosity and cohesion in the fresh state, which makes it particularly suitable for 3D printing applications. The FRIL-panels can be used for internal partitions, external infills, and suspended ceilings of buildings as more effective solutions than conventional plasterboard ones, with better thermal insulation and acoustic absorption properties due to the internal air-void microstructure. The aim of this work is to investigate the out-of-plane resistance of FRIL-panels, prepared with a density of 800kg/m3, under displacement-controlled three-point bending tests. In view of potential use in the precast industry, the FRIL-panels were placed into an accelerated concrete curing tank so as to speed up the overall production process. Modulus of rupture, ultimate deflection and collapse mode of FRIL-panels are critically analysed and discussed

Effects of β2-receptor stimulation by indacaterol in chronic heart failure treated with selective or non-selective β-blockers: a randomized trial

Alveolar \u3b22-receptor blockade worsens lung diffusion in heart failure (HF). This effect could be mitigated by stimulating alveolar \u3b22-receptors. We investigated the safety and the effects of indacaterol on lung diffusion, lung mechanics, sleep respiratory behavior, cardiac rhythm, welfare, and exercise performance in HF patients treated with a selective (bisoprolol) or a non-selective (carvedilol) \u3b2-blocker. Study procedures were performed before and after indacaterol and placebo treatments according to a cross-over, randomized, double-blind protocol in forty-four patients (27 on bisoprolol and 17 on carvedilol). No differences between indacaterol and placebo were observed in the whole population except for a significantly higher VE/VCO2 slope and lower maximal PETCO2 during exercise with indacaterol, entirely due to the difference in the bisoprolol group (VE/VCO2 31.8\u2009\ub1\u20095.9 vs. 28.5\u2009\ub1\u20095.6, p\u2009<\u20090.0001 and maximal PETCO2 36.7\u2009\ub1\u20095.5 vs. 37.7\u2009\ub1\u20095.8\u2009mmHg, p\u2009<\u20090.02 with indacaterol and placebo, respectively). In carvedilol, indacaterol was associated with a higher peak heart rate (119\u2009\ub1\u200934 vs. 113\u2009\ub1\u200930 bpm, with indacaterol and placebo) and a lower prevalence of hypopnea during sleep (3.8 [0.0;6.3] vs. 5.8 [2.9;10.5] events/hour, with indacaterol and placebo). Inhaled indacaterol is well tolerated in HF patients, it does not influence lung diffusion, and, in bisoprolol, it increases ventilation response to exercise

A Comprehensive Overview of the Temperature-Dependent Modeling of the High-Power GaN HEMT Technology Using mm-Wave Scattering Parameter Measurements (Invited Paper)

The gallium-nitride (GaN) high electron-mobility transistor (HEMT) technology has emerged as an attractive candidate for high-frequency, high-power, and high-temperature applications due to the unique physical characteristics of the GaN material. Over the years, much effort has been spent on measurement-based modeling since accurate models are essential for allowing the use of this advanced transistor technology at its best. The present analysis is focused on the modeling of the scattering (S-) parameter measurements for a 0.25 μm GaN HEMT on silicon carbide (SiC) substrate at extreme operating conditions: a large gate width (i.e., the transistor is based on an interdigitated layout consisting of ten fingers, each with a length of 150 μm, resulting in a total gate periphery of 1.5 mm), a high ambient temperature (i.e., from 35 °C up to 200 °C with a step of 55 °C), a high dissipated power (i.e., 5.1 W at 35 °C), and a high frequency in the millimeter-wave range (i.e., from 200 MHz up to 65 GHz with a step of 200 MHz). Three different modeling approaches are investigated: the equivalent-circuit model, artificial neural networks (ANNs), and gated recurrent units (GRUs). As is shown, each modeling approach has its pros and cons that need to be considered, depending on the target performance and their specifications. This implies that an appropriate selection of the transistor modeling approach should be based on discerning and prioritizing the key features that are indeed the most important for a given application

Microbial assemblages in pressurized antarctic brine pockets (Tarn flat, northern Victoria land): A hotspot of biodiversity and activity

Two distinct pressurized hypersaline brine pockets (named TF4 and TF5), separated by a thin ice layer, were detected below an ice-sealed Antarctic lake. Prokaryotic (bacterial and archaeal) diversity, abundances (including virus-like particles) and metabolic profiles were investigated by an integrated approach, including traditional and new-generation methods. Although similar diversity indices were computed for both Bacteria and Archaea, distinct bacterial and archaeal assemblages were observed. Bacteroidetes and Gammaproteobacteria were more abundant in the shallowest brine pocket, TF4, and Deltaproteobacteria, mainly represented by versatile sulphate-reducing bacteria, dominated in the deepest, TF5. The detection of sulphate-reducing bacteria and methanogenic Archaea likely reflects the presence of a distinct synthrophic consortium in TF5. Surprisingly, members assigned to hyperthermophilic Crenarchaeota and Euryarchaeota were common to both brines, indicating that these cold habitats host the most thermally tolerant Archaea. The patterns of microbial communities were different, coherently with the observed microbiological diversity between TF4 and TF5 brines. Both the influence exerted by upward movement of saline brines from a sub-surface anoxic system and the possible occurrence of an ancient ice remnant from the Ross Ice Shelf were the likely main factors shaping the microbial communities

Effects of heavy ion particle irradiation on spore germination of bacillus spp. From extremely hot and cold environments

Extremophiles are optimal models in experimentally addressing questions about the effects of cosmic radiation on biological systems. The resistance to high charge energy (HZE) particles, and helium (He) ions and iron (Fe) ions (LET at 2.2 and 200 keV/µm, respectively, until 1000 Gy), of spores from two thermophiles, Bacillus horneckiae SBP3 and Bacillus licheniformis T14, and two psychrotolerants, Bacillus sp. A34 and A43, was investigated. Spores survived He irradiation better, whereas they were more sensitive to Fe irradiation (until 500 Gy), with spores from thermophiles being more resistant to irradiations than psychrotolerants. The survived spores showed different germination kinetics, depending on the type/dose of irradiation and the germinant used. After exposure to He 1000 Gy, D-glucose increased the lag time of thermophilic spores and induced germination of psychrotolerants, whereas L-alanine and L-valine increased the germination efficiency, except alanine for A43. FTIR spectra showed important modifications to the structural components of spores after Fe irradiation at 250 Gy, which could explain the block in spore germination, whereas minor changes were observed after He radiation that could be related to the increased permeability of the inner membranes and alterations of receptor complex structures. Our results give new insights on HZE resistance of extremophiles that are useful in different contexts, including astrobiology

Dapagliflozin treatment is associated with a reduction of epicardial adipose tissue thickness and epicardial glucose uptake in human type 2 diabetes

Objective: We recently demonstrated that treatment with sodium-glucose cotransporter-2 inhibitors (SGLT-2i) leads to an increase in myocardial flow reserve in patients with type 2 diabetes (T2D) with stable coronary artery disease (CAD). The mechanism by which this occurs is, however, unclear. One of the risk factors for cardiovascular disease is inflammation of epicardial adipose tissue (EAT). Since the latter is often increased in type 2 diabetes patients, it could play a role in coronary microvascular dysfunction. It is also well known that SGLT-2i modify adipose tissue metabolism. We aimed to investigate the effects of the SGLT-2i dapagliflozin on metabolism and visceral and subcutaneous adipose tissue thickness in T2D patients with stable coronary artery disease and to verify whether these changes could explain observed changes in myocardial flow. Methods: We performed a single-center, prospective, randomized, double-blind, controlled clinical trial with 14 T2D patients randomized 1:1 to SGLT-2i dapagliflozin (10 mg daily) or placebo. The thickness of visceral (epicardial, mediastinal, perirenal) and subcutaneous adipose tissue and glucose uptake were assessed at baseline and 4 weeks after treatment initiation by 2-deoxy-2-[18F]fluoro-D-glucose Positron Emission Tomography/Computed Tomography during hyperinsulinemic euglycemic clamp. Results: The two groups were well-matched for baseline characteristics (age, diabetes duration, HbA1c, BMI, renal and heart function). Dapagliflozin treatment significantly reduced EAT thickness by 19% (p = 0.03). There was a significant 21.6% reduction in EAT glucose uptake during euglycemic hyperinsulinemic clamp in the dapagliflozin group compared with the placebo group (p = 0.014). There were no significant effects on adipose tissue thickness/metabolism in the other depots explored. Conclusions: SGLT-2 inhibition selectively reduces EAT thickness and EAT glucose uptake in T2D patients, suggesting a reduction of EAT inflammation. This could explain the observed increase in myocardial flow reserve, providing new insights into SGLT-2i cardiovascular benefits