Evaluating the human ongoing visual search performance by eye tracking application and sequencing tests

Human visual search is an everyday activity that enables humans to explore the real world. Given the visual input, during a visual search, it is necessary to select some aspects of input to shift the gaze to next target. The aim of the study is to develop a mathematical method able to evaluate the visual selection process during the execution of a high cognitively demanding task such as the trial making test part B (TMT). The TMT is a neuro-psychological instrument where numbers and letters should be connected to each other in numeric and alphabetic order. We adapted the TMT to an eye-tracking version, and we used a vector model, the "eight pointed star" (8PS), to discover how selection (fixations) guides next exploration (saccades) and how human top-down factors interact with bottom-up saliency. The results reported a trend to move away from the last fixations correlated to the number of distracters and the execution performance.     

Dynamic state and parameter estimation applied to neuromorphic systems

Neuroscientists often propose detailed computational models to probe the properties of the neural systems they study. With the advent of neuromorphic engineering, there is an increasing number of hardware electronic analogs of biological neural systems being proposed as well. However, for both biological and hardware systems, it is often difficult to estimate the parameters of the model so that they are meaningful to the experimental system under study, especially when these models involve a large number of states and parameters that cannot be simultaneously measured. We have developed a procedure to solve this problem in the context of interacting neural populations using a recently developed dynamic state and parameter estimation (DSPE) technique. This technique uses synchronization as a tool for dynamically coupling experimentally measured data to its corresponding model to determine its parameters and internal state variables. Typically experimental data are obtained from the biological neural system and the model is simulated in software; here we show that this technique is also efficient in validating proposed network models for neuromorphic spike-based very large-scale integration (VLSI) chips and that it is able to systematically extract network parameters such as synaptic weights, time constants, and other variables that are not accessible by direct observation. Our results suggest that this method can become a very useful tool for model-based identification and configuration of neuromorphic multichip VLSI systems.     

Joining silicon nitride to itself and to metals

This article reviews the progress that has been made in developing and applying joining techniques for Si₃N₄ and discusses our understanding of the influence of process selection on the materials science of the formation and properties of joints. High-performance Si₃N₄ joints can be produced, but it is clear that much work remains to be done before the use of such joints in hot-stressed applications can be disregarded as a problem.     

Design,Synthesis, Biological Activity,and Structural Analysis of Lactam‐Constrained PTPRJ Agonist Peptides

PTPRJ is a receptor‐like protein tyrosine phosphatase mainly known for its antiproliferative and tumor‐suppressive functions. PTPRJ dephosphorylates several growth factors and their receptors, negatively regulating cell proliferation and migration. We recently identified a disulfide‐bridged nonapeptide, named PTPRJ‐19 (H‐[Cys‐His‐His‐Asn‐Leu‐Thr‐His‐Ala‐Cys]‐OH), which activates PTPRJ, thereby causing cell growth inhibition and apoptosis of both cancer and endothelial cells. With the aim of replacing the disulfide bridge by a chemically more stable moiety, we have synthesized and tested a series of lactam analogues of PTPRJ‐19 . This replacement led to analogues with higher activity and greater stability than the parent peptide.     

High-Throughput ICP-MS and Chemometrics for Exploring the Major and Trace Element Profile of the Mediterranean <Emphasis Type="Italic">Sepia</Emphasis> Ink

Microwave-assisted sample digestion and inductively coupled plasma-mass spectrometry (ICP-MS) were considered for exploring major and trace elements in the Mediterranean Sepia ink. The present work aims to (a) fully validate the employed ICP-MS method and compare the Hg determinations by ICP-MS with those obtained by a direct mercury analyzer (DMA) and (b) interpret quantitative data by chemometrics and perform a risk/benefit analysis for assessing the quality/safety of Sepia ink. DMA gave Hg determinations similar to the ICP-MS counterpart (p > 0.05), confirming its reliability for food analysis. Sepia ink demonstrated to be both a reservoir of “healthy” elements and a sink of potential toxic metals. In fact, a good contribution of major and essential trace metals to the established RDAs was revealed, and, at the same time, potentially toxic elements showed to accumulate depending upon the environmental conditions, although not representing a risk for human consumers.     

Colocalization and Interaction Study of Neuronal JNK3, JIP1, and β-Arrestin2 Together with PSD95

c-Jun N-terminal kinases (JNKs) are stress-activated serine/threonine protein kinases belonging to the mitogen-activated protein kinase (MAPK) family. Among them, JNK3 is selectively expressed in the central nervous system, cardiac smooth muscle, and testis. In addition, it is the most responsive JNK isoform to stress stimuli in the brain, and it is involved in synaptic dysfunction, an essential step in neurodegenerative processes. JNK3 pathway is organized in a cascade of amplification in which signal transduction occurs by stepwise, highly controlled phosphorylation. Since different MAPKs share common upstream activators, pathway specificity is guaranteed by scaffold proteins such as JIP1 and β-arrestin2. To better elucidate the physiological mechanisms regulating JNK3 in neurons, and how these interactions may be involved in synaptic (dys)function, we used (i) super-resolution microscopy to demonstrate the colocalization among JNK3–PSD95–JIP1 and JNK3–PSD95–β-arrestin2 in cultured hippocampal neurons, and (ii) co-immunoprecipitation techniques to show that the two scaffold proteins and JNK3 can be found interacting together with PSD95. The protein-protein interactions that govern the formation of these two complexes, JNK3–PSD95–JIP1 and JNK3–PSD95–β-arrestin2, may be used as targets to interfere with their downstream synaptic events.     

Impact of Vitamin D in Prophylaxis and Treatment in Tuberculosis Patients

Vitamin D plays a crucial role in many infectious diseases, such as tuberculosis (TB), that remains one of the world’s top infectious killers with 1.5 million deaths from TB in 2021. Vitamin D suppresses the replication of Mycobacterium tuberculosis in vitro and showed a promising role in TB management as a result of its connection with oxidative balance. Our review encourages the possible in vivo benefit of a joint administration with other vitamins, such as vitamin A, which share a known antimycobacterial action with vitamin D. However, considering the low incidence of side effects even at high dosages and its low cost, it would be advisable to assess vitamin D level both in patients with active TB and high-risk groups and administer it, at least to reach sufficiency levels.     

Self-propagating combustion synthesis of intermetallic matrix composites in the ISS

Combustion Synthesis experiments have been performed on the ISS (International Space Station) during the Belgian taxi-flight mission ODISSEA in November 2002, in the framework of the ESA-coordinated project COSMIC (Combustion Synthesis under Microgravity Conditions). The main objective of the experiments was to investigate the general physico-chemical mechanisms of combustion synthesis processes and the formation of products microstructure. Within the combustion zone, a number of gravity-dependent phenomena occur, while other phenomena are masked by gravity. Under certain conditions, gravity-dependent secondary processes may also occur in the heat-affected zone after combustion. To study the influence of gravity, a specially dedicated reactor ensemble was designed and used in the Microgravity Science Glovebox (MSG) onboard the ISS. In this work, the experiment design is first discussed in terms of the experimental functionality and reactor ensemble integration in the MSG. To investigate microstructure formation, a sample constituted by a cylindrical portion followed by a conical one, the latter being inserted inside a massive copper block, is used. The experiment focused on the synthesis of intermetallic matrix composites (IMCs) based on the Al-Ti-B system. Depending on the composition, different intermetallic compounds (TiAl and TiAl₃) can be formed as matrix phase while TiB2 represents the reinforcing particulate phase. During the ISS mission, six samples with a relatively high green density of 65%TD have successfully been processed. The influence of the composition on the combustion process will be examined.     

Organochlorine pesticide, polychlorinated biphenyl and heavy metal concentrations in wolves (Canis lupus L. 1758) from north-west Russia

The wolf Canis lupus is a major terrestrial predator in eastern Europe and, as a top carnivore, may be exposed to high concentrations of contaminants that are readily transferred through the food chain. Despite this, there are few published data on pollutant and pesticide levels in wolves. This study utilised tissues from animals legally killed by hunters for other reasons (animals were not killed for the purposes of this study) to carry out the only detailed investigation of contaminants in wolves in Europe and the first in animals from Eastern Europe. The livers of 58 wolves from the Tver and Smoliensk regions of northwest Russia (54°N 31°E to 57°N 35°E) were analysed for seven organochlorine pesticides, 24 PCB congeners, Aroclor 1254-matched summed PCBs (ΣPCBs), total mercury, cadmium and lead. Cadmium, most of the organochlorine pesticides and many PCB congeners were not detectable in any of the wolves. Hexachlorobenzene, alpha-HCH, pp′DDE, PCB congeners 118, 138, 149 and 156 and lead were detected in up to 6% of livers. Dieldrin, PCB congeners 153, 170 and 180, ΣPCBs and mercury were detected more frequently. Contaminant levels were generally low; maximum wet weight concentrations of any of the organochlorine pesticides, ΣPCBs and mercury were less than 0.1, 1 and 0.25 μg g⁻¹, respectively. PCB congeners 153, 170 and 180 accounted for 41% of the ΣPCBs. Dieldrin, ΣPCBs and mercury concentrations did not vary significantly between males and females nor between adult and juvenile (<12 months old) wolves apart from the ΣPCB concentration, which was on average five times higher in adults than juveniles. Liver residues were generally below the level normally associated with adverse effects except for lead levels which exceeded the critical 5 μg g⁻¹ dry wt. concentration in three of the 58 animals examined.