Circulatory Neutrophils Exhibit Enhanced Neutrophil Extracellular Trap Formation in Early Puerperium: NETs at the Nexus of Thrombosis and Immunity

Pregnancy is associated with elevated maternal levels of cell-free DNA of neutrophil extracellular trap (NET) origin, as circulatory neutrophils exhibit increased spontaneous NET formation, mainly driven by G-CSF and finely modulated by sex hormones. The postpartum period, on the other hand, involves physiological alterations consistent with the need for protection against infections and fatal haemorrhage. Our findings indicate that all relevant serum markers of neutrophil degranulation and NET release are substantially augmented postpartum. Neutrophil pro-NETotic activity in vitro is also upregulated particularly in post-delivery neutrophils. Moreover, maternal puerperal neutrophils exhibit a strong pro-NETotic phenotype, associated with increased levels of all key players in the generation of NETs, namely citH3, MPO, NE, and ROS, compared to non-pregnant and pregnant controls. Intriguingly, post-delivery NET formation is independent of G-CSF in contrast to late gestation and complemented by the presence of TF on the NETs, alterations in the platelet activity status, and activation of the coagulation cascade, triggered by circulating microparticles. Taken together, our results reveal the highly pro-NETotic and potentially procoagulant nature of postpartum neutrophils, bridging an overt immune activation with possible harmful thrombotic incidence.     

Optical and Raman scattering studies on SnS nanoparticles

Tin sulfide nanoparticles were synthesized through wet chemical route. Structure and phase purity were confirmed by powder XRD. Morphology and size were identified from TEM and AFM. The room temperature photoluminescence spectrum shows the band edge emission at 1.57 eV. The direct and indirect band gaps are estimated from UV-vis-NIR absorption spectrum as 1.78 and 1.2 eV, respectively. Blue shift of 0.48 eV observed for direct transition and 0.2 eV for indirect transition as compared to bulk band gap is due to quantum confinement effect. The Raman spectrum of SnS nanoparticles shows all the predicted Raman modes which show shift towards lower wave number side in comparison with those of the SnS single crystal. This is attributed to phonon confinement.     

A smart spectrum utilization approach using multiantenna‐based cognitive relays in cognitive radio network

Efficient spectrum utilization is a promising technique for a prolonged unused radio frequency (RF) spectrum in a wireless network. In this paper, an adaptive spectrum sharing cognitive radio (CR) network has been proposed consisting of a primary user (PU) and secondary user transmitter (SU ? Tx) that communicates with secondary user receiver (SU ? Rx) via multiantenna‐based proactive decode‐and‐forward (DF) relay selection scheme. In our model, strategically an adaptable joint venture on underlay/overlay protocol is defined based on channel occupancy using spectrum sensing technique. Here, secondary transmitters (i.e., source transmitter) continuously sense the PU activities by energy detector and can simultaneously transmit to secondary receivers. Depending on sensing result secondary transmitters automatically switches in underlay mode if PU is active otherwise operates in overlay mode. The advantage of this scheme is that the joint mode of transmission allows the SUs to maximize their transmission rate. The outage performance at SU ? Rx and closed‐form expressions of joint underlay/overlay protocol has been evaluated. The power control policies at different transmitter nodes are taken care of. With the same diversity order, a trade‐off between multiantenna and multirelay is shown. This comparison shows improvement in outage behavior when the count in relays surpasses the number of antennas. Finally, the analytical model of smart efficient spectrum utilization without harming license users in CR is validated by MATLAB simulation.     

Direct synthesis of hydrogen peroxide from hydrogen and oxygen: An overview of recent developments in the process

Hydrogen peroxide (H₂O₂) is an important commodity chemical and its demand is growing significantly in the chemical synthesis due to its “green” character. Currently, H₂O₂ is produced almost exclusively by the anthraquinone auto-oxidation (AO) process. The AO process involves indirect oxidation of hydrogen and thus avoids potentially explosive H₂/O₂ mixture. However, this large-scale process presents significant safety issues associated with the transport of bulk H₂O₂. Moreover, the AO process can hardly be considered an environmentally friendly method. In view of this, more economical and environmentally cleaner routes have been explored for the production of H₂O₂. The liquid-phase catalytic direct synthesis of H₂O₂ from H₂ and O₂ offers an attractive green technology for small-scale/on-site production of H₂O₂. However, the direct synthesis process suffers from two major drawbacks: (i) potential hazards associated with H₂/O₂ mixtures and (ii) poor selectivity for H₂O₂ because the catalysts used for H₂O₂ synthesis are also active for its decomposition and hydrogenation to water as well as for H₂ combustion. These serious issues and the recent developments in the direct H₂O₂ synthesis are discussed in this review. The roles of protons (H⁺) and halide ions in promoting the H₂O₂ selectivity are also examined in detail.     

Mitochondrial Dysfunction as a Driver of Cognitive Impairment in Alzheimer’s Disease

Alzheimer’s disease (AD) is the most frequent cause of age-related neurodegeneration and cognitive impairment, and there are currently no broadly effective therapies. The underlying pathogenesis is complex, but a growing body of evidence implicates mitochondrial dysfunction as a common pathomechanism involved in many of the hallmark features of the AD brain, such as formation of amyloid-beta (Aβ) aggregates (amyloid plaques), neurofibrillary tangles, cholinergic system dysfunction, impaired synaptic transmission and plasticity, oxidative stress, and neuroinflammation, that lead to neurodegeneration and cognitive dysfunction. Indeed, mitochondrial dysfunction concomitant with progressive accumulation of mitochondrial Aβ is an early event in AD pathogenesis. Healthy mitochondria are critical for providing sufficient energy to maintain endogenous neuroprotective and reparative mechanisms, while disturbances in mitochondrial function, motility, fission, and fusion lead to neuronal malfunction and degeneration associated with excess free radical production and reduced intracellular calcium buffering. In addition, mitochondrial dysfunction can contribute to amyloid-β precursor protein (APP) expression and misprocessing to produce pathogenic fragments (e.g., Aβ1-40). Given this background, we present an overview of the importance of mitochondria for maintenance of neuronal function and how mitochondrial dysfunction acts as a driver of cognitive impairment in AD. Additionally, we provide a brief summary of possible treatments targeting mitochondrial dysfunction as therapeutic approaches for AD.     

Ensemble based technique for the assessment of fetal health using cardiotocograph – a case study with standard feature reduction techniques

Multimedia Tools and Applications - Intrauterine fetal hypoxia is one of the leading cause of perinatal mortality and morbidity. This can eventually lead to severe neurological damage like cerebral...     

Direct formation of H2O2 from H2 and O2 and decomposition/hydrogenation of H2O2 in aqueous acidic reaction medium over halide-containing Pd/SiO2 catalytic system

Formation of H₂O₂ from H₂ and O₂ and decomposition/hydrogenation of H₂O₂ have been studied in aqueous acidic medium over Pd/SiO₂ catalyst in presence of different halide ions (viz. F⁻, Cl⁻ and Br⁻). The halide ions were introduced in the catalytic system via incorporating them in the catalyst or by adding into the reaction medium. The nature of the halide ions present in the catalytic system showed profound influence on the H₂O₂ formation selectivity in the H₂ to H₂O₂ oxidation over the catalyst. The H₂O₂ destruction via catalytic decomposition and by hydrogenation (in presence of hydrogen) was also found to be strongly dependent upon the nature of the halide ions present in the catalytic system. Among the different halides, Br⁻ was found to selectivity promote the conversion of H₂ to H₂O₂ by significantly reducing the H₂O₂ decomposition and hydrogenation over the catalyst. The other halides, on the other hand, showed a negative influence on the H₂O₂ formation by promoting the H₂ combustion to water and/or by increasing the rate of decomposition/hydrogenation of H₂O₂ over the catalyst. An optimum concentration of Br⁻ ions in the reaction medium or in the catalyst was found to be crucial for obtaining the higher H₂O₂ yield in the direct synthesis.     

An analysis of the eddy effect in through-silicon vias based on Cu and CNT bundles: the impact on crosstalk and power

Journal of Computational Electronics - The performance of three-dimensional integrated circuits primarily depends on the filler material used in the through-silicon vias (TSVs). The most widely...     

Ribosome: The Structure–Function Relation and a New Paradigm to the Protein Folding Problem

The rate of protein synthesis is about seven and fifteen amino acids per second, in the eukaryotic and the bacterial ribosome, respectively. Hence, a few minutes is required to synthesize a polypeptide of an average length. This is much longer than the time needed for the hydrophobic collapse (folding) to take place. So a polypeptide gets enough time to form its local secondary to tertiary structures cotranslationally and put such segments in proper order while in association with the ribosome, unless something prevents its entire length from folding. As reported earlier, ribosomes from prokaryotes, eukaryotes, and mitochondria act as molds for protein folding, and each mold has a set of recognition sites for all proteins. More specifically, the mold is the peptidyl transferase center (PTC), a part of the large RNA of the large ribosomal subunit. Specific amino acids from different random coil regions in a protein interact with specific nucleotides in the PTC, which brings the entire length of the protein into the small space of the PTC mold. The mold thus helps to stabilize the entropy-driven collapsed state of the polypeptide. The process also divides the protein into small segments; each segment is connected at two ends with two nucleotides and can fold in the ribosomal environment. The segments dissociate in such a sequence that the organization proceeds hierarchically from the core of the globular protein radially towards the outer surface. Then the protein dissociates from the ribosome in a “folding competent state” which does the final fine tuning in folding outside the ribosome. While the ribosomal contact and release are over in 1–2 minutes in vitro, the fine tuning takes about 5–10 minutes. Release from the ribosome needs no added energy factor from outside, like ATP.