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The article discusses a study which described the brazing and joint characterization of 3D carbon-carbon (C-C) composites with resin+CVI carbon matrices to copper (Cu)-clad-molybdenum (Mo) using two titanium (Ti)-containing Ag-Cu active braze alloys. Several applications of C-C composites include nose cone and leading edges of the space shuttle, rocket nozzles, exit cones, heat shield and aircraft braking systems. Factors used for the characterization of brazed joints include optical microscopy and field emission scanning electron microscopy (FESEM).

p-Cycle-based protection is one of the most promising techniques of span protection in optical networks because of mesh-like efficiency and ring-like speed. We have presented a modified distributed cycle preconfiguration protocol (MDCPC) which reduces the computational complexities, by finding all the copies of the same p-cycle in single iteration. All the copies of the same p-cycle are aggregated together to reduce the number of switching fabrics and the amount of signalling traffic. Further, the restoration paths provided by the p-cycles are usually many hops long, as longer p-cycles provide better efficiency. Obviously, with longer p-cycles, the nodes in the working path may be repeated in the restoration path provided by the p-cycle. They will give rise to loop backs in the restored path. The restored path lengths will unnecessarily be longer due to these loop backs. If these loop backs can be removed, the restored path length will be reduced significantly, and redundant capacity will also be released. In the present work, a distributed protocol has been presented for the implementation of removal of loop back (RLB) algorithm to reconfigure the restored path. The reduction in the restored path length also depends on the fact that which p-cycle is being used to protect a particular path. The problem has been formulated as optimum p-cycle allocation (OPA) problem and solved with the Hungarian algorithm. The average lengths of the restored paths with and without RLB for the networks with 2.0 average nodal degree have also been derived. [ABSTRACT FROM PUBLISHER]

Hydroponically-grown Pisum sativum plants were sensitive to Ni2+ (100–1000 µmol/L). Lower Ni2+ concentration (25 µmol/L) stimulated general growth up to 20 d. Nickel (Ni)-free plants showed nodulation (average 27 per plant), but the frequency went down to 82% even in 100 µmol/L Ni2+. The Ni2+ concentration, when raised to 200 or 300 µmol/L, inhibited nodulation completely. The Ni2+ accumulation in P. sativum was concentration- and time-dependent. External Ni2+ concentration (200 or 300 µmol/L) contributed cation buildup of 34 µg g−1 dw, average. The root/shoot share of Ni2+ was invariably 60 : 40 indicating that 40% of Ni2+ accumulated gets translocated to foliar parts. Proline biosynthesis in plants was promoted by 3.36-fold. A 40:60 root/shoot share of this amino acid infers that it is synthesized primarily in foliar parts and can be adopted as a reliable metal-stress indicator. The Ni2+ load invariably lowered thiol biosynthesis in P. sativum with the exception of a 1.14-fold stimulation by the lowest Ni2+ dose (25 µmol/L) during the first 5 d. However, plants failed to sustain this stimulation any longer as the level paralleled the Ni-free control during subsequent growth. Urease activity increased to a maximum of 24.7 µmol g−1 dw during 20 d although it declined to 22.4 units at the end of the experiment (30 d). The marginal stimulation of urease by Ni2+ can be arranged as 100 > 25 > 0 > 200 > 300 µmol/L. Pisum sativum roots even at the seedling stage, had double the amount of urease as shoots. It is suggested that this may primarily be to facilitate the plant assimilation of urea from the ambient environment. [ABSTRACT FROM AUTHOR]

The plant Swertia chirata (Gentianaceae) is known for its multifarious medicinal value in the Indian system of medicine (Ayurveda). Its methanol extracts having antidiabetic activity contains mangiferin, amarogentin, amaroswerin, sweroside and swertiamarin as active constituents. The pharmacokinetics of mangiferin and amarogentin have been carried out after intravenous administration of pure standards and extract from S. chirata (CT) in rabbits to assess systemic interaction. The remaining three components were also monitored in plasma for pharmacokinetic estimation based on the ratio analysis method. Mangiferin was characterized by a relative low clearance (∼0.14 L/h/kg) and a lesser volume of distribution (∼0.15 L/kg), while amarogentin exhibited a rapid clearance (∼2.62 L/h/kg) and wide distribution (∼1.08 L/kg) from the systemic circulation. No significant difference was observed in pharmacokinetic parameters of mangiferin and amarogentin either administered alone or as CT formulation in rabbits. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

P-cycles are one of the most promising techniques used for span protection in optical networks. However when p-cycle is used to provide protection to any failed span, there may be overlapping of some nodes in the working path and in the restoration path provided by the p-cycle. These nodes are repeated in the restored path; hence redundant link capacity is used. These repetitions will form loops at the overlapping nodes. To remove these loops and release the redundant capacity, an algorithm is developed to reconfigure the restored path. This aspect of the p-cycle has not been discussed so far in the literature. The capacities required without reconfiguration and after reconfiguration have been compared. It has been found that with reconfiguration, considerable amount of capacity can be released, and the restored path length can also be reduced significantly [ABSTRACT FROM PUBLISHER]

Dunaliella salina is a favourable source of high lipid feedstock for biofuel and medicinal chemicals. Low biomass output from microalgae is a significant barrier to industrial-scale commercialisation. The current study aimed to determine how photosynthetic efficiency, carbon fixation, macromolecular synthesis, accumulation of neutral lipids, and antioxidative defence (ROS scavenging enzyme activities) of D. salina cells were affected by different light intensities (LI) (50, 100, 200, and 400 µmol m−2 s−1). The cells when exposed to strong light (400 µmol m−2 s−1) led to reduction in chlorophyll a but the carotenoid content increased by 19% in comparison to the control (LI 100). The amount of carbohydrate changed significantly under high light and in spite of stress inflicted on the cells by high irradiation, a considerable increase in activity of carbonic anhydrase and fixation rate of CO2 were recorded, thus, preserving the biomass content. The high light exposed biomass when subjected to nitrogen-deficient medium led to increase in lipid content (59.92% of the dry cell weight). However, neutral lipid made up 78.26% of the total lipid while other lipids like phospholipid and glycolipid content decreased, showing that the lipid was redistributed in these cells under nitrogen deprivation, making the organism more appropriate for biodiesel/jet fuel use. Although D. salina cells had a relatively longer generation time (3.5 d) than other microalgal cells, an economic analysis concluded that the amount of carotenoid they produced and the quality of their lipids made them more suited for commercialization. [ABSTRACT FROM AUTHOR]

The microalga, Dunaliella salina, is a treasure of fine chemicals, carotenoids, and lipids of industrial importance. The present investigation focused on the maximization of lipid content in the context of biofuel. Mixotrophic cultures growing in different combinations of sodium bicarbonate (NaHCO3) and glucose (Glu) or sodium acetate (Na-Ace) were monitored for essential growth parameters such as photosynthesis, dry biomass, and Chl a content. The maximum photosynthetic quantum yield (Fv/Fm) of all the screened mixotrophic cultures along with control ranged between 0.63 and 0.72, indicating the cells were in a good physiological state. The highest biomass productivity (33.46 ± 0.58 mg/L/d) was recorded in 1.0 mM NaHCO3 + 1.0 mM Glu-containing cultures. However, the highest lipid content (56% DCW) was recorded in 1.0 mM NaHCO3 + 0.5 mM Na-Ace-containing cultures. Interestingly, a 1.7-fold higher starch content (72.3 μg/mL) was recorded in 0.25 mM NaHCO3 + 0.5 mM Na-Ace over 1.0 mM NaHCO3 + 0.5 mM Na-Ace-containing cultures. Thus, data indicated that the higher concentration of NaHCO3 along with Na-Ace favoured lipid biosynthesis, while the lower concentration of NaHCO3 with Na-Ace favoured starch synthesis. Thus, substrate provision determined the desired products. Lipids obtained from D. salina at stage II (nitrogen-deficient condition) possessed ideal fuel properties according to international standards of EN 14214 and ASTM D6751. Therefore, the present work explored the threshold level of bicarbonate along with Na-Ace which was able to maintain good physiological status and produced higher lipids with better biodiesel properties. [ABSTRACT FROM AUTHOR]

Abstract: High conductivity graphite foams with low (125 kg m−3), medium (260–270 kg m−3), and high (650 and 797 kg m−3) densities were integrated with copper-clad-molybdenum using an Ag–Cu–Ti braze alloy (63Ag–35.3Cu-1.75Ti) as powder and foil. The effects of foam density (125–650 kg m−3), cladding thickness (0.1–0.3 mm), and Cu–Mo–Cu ratio (in %: 13/74/13 and 20/60/20), on microstructure and composition were evaluated using optical microscopy and scanning electron microscopy coupled with energy dispersive spectroscopy. Low-density foams showed more extensive braze penetration than high-density foams. The carbon/braze interfaces were well-bonded and enriched in Ti. The joint microstructure and penetration depth were independent of clad layer thickness and Cu/Mo/Cu ratio. Differences in elemental distribution were noted between joints made using foil and powders; with foil, the Ti and Cu concentrations were inversely related (high Ti concentrations overlapped areas of low Cu concentrations and vice versa) whereas with powders, high Cu and Ti concentrations coincided. Although a thick Cu-cladding increases the coefficient of thermal expansion (CTE) of the Cu-clad-Mo substrate and the CTE mismatch relative to foam, this effect is offset by better stress accommodation with a thick clad layer. Thermal calculations verified that thermal resistance decreased with increasing thickness of clad layer in joints. [Copyright &y& Elsevier]

Abstract: CVD silicon carbide was brazed to itself using two Ag–Cu–Ti braze alloys reinforced with SiC particulates to control braze thermal expansion and enhance joint strength. Powders of the braze alloys, Ticusil (composition in wt%: Ag–26.7Cu–4.5Ti, TL: 900°C) and Cusil-ABA (Ag–35.3Cu–1.75Ti, TL: 815°C) were pre-mixed with 5, 10 and 15wt% SiC particulates (∼20–30μm) using glycerin to create braze pastes that were applied to the surfaces to be joined. Joints were vacuum brazed and examined using optical microscopy (OM), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS) and the Knoop hardness test. The SiC particles were randomly distributed in the braze matrix and bonded to it via reaction with the titanium from the braze alloy. Titanium together with Si and C segregated at the particle/braze interface, and promoted nucleation and precipitation of the Cu-rich secondary phase on particle surfaces. The Si–Ti–C-rich reaction layers also formed at the interface between CVD SiC substrate and the braze alloy. The loss of Ti in the reaction with SiC particulates did not impair either the bond quality or the thickness of the reaction layer on the CVD SiC substrate. Microhardness measurements showed that the dispersed SiC particulates lowered the braze hardness by depleting the braze matrix of Ti. Theoretical calculations indicated the CTE of the braze to decrease by nearly 45–60% with the incorporation of about 45vol% SiC. [Copyright &y& Elsevier]

Abstract: Silicon nitride/silicon nitride joints were vacuum brazed at 1317K for 5min and 30min using ductile Cu-base active metal interlayers. The joints were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), electron back scattered diffraction (EBSD), and transmission electron microscopy (TEM). An inhomogeneous Ti-rich reaction layer (∼2–3μm thick) formed in 5min at the Si3N4/braze interface. The inhomogeneity disappeared after brazing for 30min and was replaced with a compact and featureless reaction zone. TEM studies revealed fine grains in the reaction layer, and larger grains in the inner part of the joint interfaces. The joints were crack-free and presented features associated with plastic deformation, which indicated accommodation of strain associated with CTE mismatch. Electron Backscatter diffraction (EBSD) revealed a highly textured braze alloy interlayer and its crystallographic orientation was determined. The formation of additional phases at the joint interface during brazing is discussed. [Copyright &y& Elsevier]

Abstract: The wetting behavior of liquid Ni and NiW10 on MgO(100) single crystals was examined by the sessile drop method at 1773K in flowing Ar. A special procedure was used for in situ opening of the Ni/MgO and NiW10/MgO interfaces directly during wettability test at high temperature. Scanning probe microscopy revealed evidence of strong surface modification of MgO(100) during wettability tests that was found to be affected by metal evaporation, the chemistry of the liquid metal and the primary oxide film. [Copyright &y& Elsevier]

Abstract: Two palladium-base brazes (Palco and Palni), and two silver-base brazes containing palladium as an alloying element (Palcusil-10 and Palcusil-15) were evaluated for oxidation resistance at 750°C, and used in joining yttria-stabilized zirconia (YSZ) to a corrosion-resistant ferritic stainless steel for possible use in solid oxide fuel cell (SOFC) interconnects. Thermogravimetric analysis (TGA), and optical and scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (EDS) were used to evaluate the braze oxidation behavior and the microstructure of the YSZ/braze/steel joints. Knoop microhardness testing was used to develop hardness profiles across the joint region. The TGA results showed that Palco and Palni exhibited the fastest and the slowest oxidation kinetics, respectively, with Palcusil-10 and Palcusil-15 exhibiting oxidation kinetics intermediate between Palco and Palni. The EDS analysis revealed the dissolution of YSZ and steel constituents in braze, and of braze constituents in the YSZ and steel, which led to metallurgically sound joints. The microhardness profiles exhibited a sharper discontinuity at the YSZ/braze interface than at the steel/braze interface, with a peak hardness of ∼1000KHN in YSZ and 150–180KHN in the steel substrate. [Copyright &y& Elsevier]

In this study, the applicability of physics informed neural networks using wavelets as an activation function is discussed to solve non-linear differential equations. One of the prominent equations arising in fluid dynamics namely Blasius viscous flow problem is solved. A linear coupled differential equation, a non-linear coupled differential equation, and partial differential equations are also solved in order to demonstrate the method's versatility. As the neural network's optimum design is important and is problem-specific, the influence of some of the key factors on the model's accuracy is also investigated. To confirm the approach's efficacy, the outcomes of the suggested method were compared with those of the existing approaches. The suggested method was observed to be both efficient and accurate., (© 2023. The Author(s).)

This work suggests a method to identify personality traits regarding the targeted film clips in real-time. Such film clips elicit feelings in people while capturing their brain impulses using the electroencephalogram (EEG) devices and examining personality traits. The Myers-Briggs Type Indicator (MBTI) paradigm for determining personality is employed in this study. The fast Fourier transform (FFT) approach is used for feature extraction, and we have used hybrid genetic programming (HGP) for EEG data classification. We used a single-channel NeuroSky MindWave 2 dry electrode unit to obtain the EEG data. In order to collect the data, thirty Hindi and English video clips were placed in a conventional database. Fifty people volunteered to participate in this study and willingly provided brain signals. Using this dataset, we have generated four two-class HGP classifiers (HGP1, HGP2, HGP3, and HGP4), one for each group of MBTI traits overall classification accuracy of the HGP classifier as 82.25% for 10-fold cross-validation partition., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Harshit Bhardwaj et al.)

The growth of COVID-19 cases in India is scaling high over the past weeks despite stringent lockdown policies. This study introduces a GPS-based tool, i.e., lockdown breaching index (LBI), which helps to determine the extent of breaching activities during the lockdown period. It is evaluated using the community mobility reports. This index ranges between 0 and 100, which implies the extent of following the lockdown policies. A score of 0 indicates that civilians strictly adhered to the guidelines while a score of 100 points to complete violation. Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS) is modified to compute the LBI. We considered fifteen states of India, where the spread of coronavirus is relatively dominant. A significant breaching activity is observed during the first phase of lockdown, and the intensity increased in the third and fourth phases of lockdown. Overall breaching activities are dominant in Bihar with LBI of 75.28. At the same time, it is observed that the majority of the people in Delhi adhered to the lockdown policies strictly, as reflected with an LBI score of 47.05, which is the lowest. Though an average rise of 3% breaching activities during the second phase of lockdown (L2.0) with reference to the first phase of lockdown (L1.0) is noticed in all the states, a decreasing trend is noticed in Delhi and Tamil Nadu. Since the beginning of third phase of lockdown L3.0, a significant rise in breaching activities is observed in every state considered for the analysis. The average LBI rise of 16.9% and 27.6% relative to L1.0 is observed at the end of L3.0 and L4.0, respectively. A positive spearman rank correlation of 0.88 is noticed between LBI and the cumulative confirmed cases. This correlation serves as evidence and enlightens the fact that the breaching activities could be one of the possible reasons that contributed to the rise in COVID-19 cases throughout lockdown., Competing Interests: Conflict of InterestThe authors declare that they have no conflict of interest., (© The Author(s), under exclusive licence to Springer Nature Switzerland AG part of Springer Nature 2021.)

Background: Taxane acute pain syndrome (TAPS) is a clinically significant side-effect of taxane chemotherapy, often described as arthralgia and myalgia that occurs 2-3 days after infusion. The aim of this study was to assess pain descriptors used by patients during their experience of TAPS., Methods: A clinical prospective cohort study was conducted on breast cancer patients who had not received prior chemotherapy and were asked to complete diaries on three consecutive docetaxel treatment cycles on days 1-7, 14, and 21 (acute phase). Questionnaires to assess pain severity, descriptors of pain, and the interference in activities due to pain were adapted from the Brief Pain Inventory and the McGill Pain Questionnaire. Telephone questionnaire follow-up was done at 1, 3, 6, 9, and 12 months following docetaxel (delayed phase)., Results: The most commonly used descriptor for acute and chronic pain was "aching" (90-96%). However, in the delayed phase of the study, "burning" (32-50%), "radiating" (39-48%), and "sharp" (40-69%) were used more often. In both acute and chronic pain phases, most patients experienced moderate/severe pain regardless of the location. Pain in cycle 1 was predictive of pain in subsequent taxane cycles (p < 0.0001). Pain in cycle 3 was predictive of chronic pain (p < 0.002)., Conclusions: The descriptors used by patients experiencing chemotherapy-induced pain (ChIP) may be reflective of the underlying mechanisms. It is suspected that TAPS initiates as an acute inflammatory pain, which over time develops into neuropathic pain, known as chemotherapy-induced peripheral neuropathy (CIPN). However, the subjective pain experience varies from patient to patient.