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In this paper, a high‐gain bidirectional DC–DC converter is presented for electric vehicles where low terminal voltage source like a supercapacitor is used along with the battery. The supercapacitor provides or absorbs large amount power during acceleration and deacceleration and extends the life of main energy source, that is, battery. The supercapacitor terminal voltage varies considerably during charging and discharging activities; hence, a bidirectional DC–DC converter with a high‐voltage conversion ratio must be used to connect the lower supercapacitor voltage to the higher DC‐link voltage. Such application requires steep voltage conversion ratio along with continuous gain‐based bidirectional DC–DC converters. In this study, a typical CuK converter is employed to produce a voltage gain of 3X and X/3 with the ability to transmit power in both directions. The suggested bidirectional converter has a continuous current on both the low‐ and high‐voltage sides, which reduces the requirement for filter capacitance and increases the lifespan of the supercapacitor and DC‐link capacitor. Further, inherent inrush current safety is provided by the proposed converter as the inclusion of an inductor in the path of capacitor charging or discharging. Both in the charging and discharging phases, a detailed steady‐state analysis of the proposed circuit was performed. Moreover, a deep discharge analysis of the supercapacitor and its implication on the performance of the converter is also investigated. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the second most common cause of cancer‐related deaths and the third most common cancer worldwide. Because of its importance in DNA biosynthesis, thymidylate synthase (TS) has gathered attention as a promising target for cancer therapy. Herein, we have designed and synthesized 12 novel 5‐(N‐Benzyl indol‐3‐yl) pyrido[2, 3‐d] pyrimidine based derivatives and assessed their anticancer activity against HCT 116, MCF‐7, Hep G2, and PC‐3 cell lines. For compounds 5 a and 5 f TS inhibitory activity was also performed along with in silico studies. Further, all the synthesized compounds exhibited anticancer activity, but particularly, compounds 5 a and 5 f were showed excellent anticancer activity having IC50 values of 1.09±0.61, 5.54±0.81, 6.44±0.91, and 5.12±0.65 μM and 1.03±0.96, 3.09±0.52, 4.12±0.59, and 7.06±0.60 μM respectively with control Raltitrexed (IC50 1.02±0.51, 1.88±0.61, 1.30±0.89, and 2.09±0.67 μM respectively) and hTS inhibitory activity with IC50 of 18.91±1.09 and 16.19±0.96 nM with control Raltitrexed (IC50 12.25±1.21 nM). Further, the mechanism of inhibition was revealed by molecular docking, which showed the binding pattern of 5 a and 5 f to the catalytic site of TS. Additionally, ADME characteristics were also in the acceptable range for these compounds. Based on the anticancer activity, SAR was also performed for lead optimization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Graphitic carbon nitride is immobilized on a graphene modified screen-printed carbon electrode (g-C 3 N 4 @GN/SPCE) for electroanalysis of BPSIP. • First SPCE-based disposable electrochemical sensor for onsite monitoring of BPSIP. • The g-C 3 N 4 @GN/SPCE has shown a very low oxidation potential of 0.65 V for the electro-oxidation of BPSIP. • A wide detection range (1–1000 µM) with a sensitivity of 0.9162 ± 0.0003 µA.µM−1.cm−2 for BPSIP sensing is observed. • It exhibited a good anti-interference property for applications in real sample matrices. A screen-printed electrochemical sensor based on a graphene-modified screen-printed carbon electrode decorated with graphitic carbon nitride (g-C 3 N 4 @GN/SPCE) was examined for its ability to act as a sensitive and selective novel sensor for on-site monitoring of an endocrine disruptor, 4-(4-isopropoxy-benzenesulfonyl)-phenol (BPSIP). The successfully prepared g-C 3 N 4 was thoroughly characterized using FESEM, TEM, EDX, FT-IR, XRD, UV– visible studies, and TGA. The prepared g-C 3 N 4 was immobilized on GN/SPCE to prepare a low-cost and disposable sensor for electroanalytical measurement of BPSIP. The concentration of nanomaterial dispersion, pH, and composition of the buffer solution were also optimized for maximal response. At the optimized conditions, BPSIP was determined by cyclic voltammetry in two linear concentration ranges (1–100 µM and 100–1000 µM) with a very low detection limit of 0.02 ± 0.01 µM and unparalleled sensitivity of 0.9162 ± 0.0003 µA.µM−1.cm−2. Further, the electrochemical oxidation of BPSIP occurred at 0.65 V, suggesting the excellent electrocatalytic performance of g-C 3 N 4 @GN/SPCE. The proposed sensor has shown high repeatability and reproducibility as well as good anti-interference properties for BPSIP sensing. The feasibility of the as-prepared sensor is also tested in biological and water samples, with excellent recoveries in the range of 98–104 % for BPSIP sensing. [ABSTRACT FROM AUTHOR]

Energy crises and climate change attracted less-explored microalgae as renewable resources. Deficiencies of nitrogen and phosphorus are the most effective inducers of lipid accumulation in microalgae but at the cost of biomass productivity. Therefore, nitrogen, phosphorus, and carbon manipulation of the culture medium was adopted for maximizing lipid as well as biomass production in Dunaliella salina. Phosphate deficiency in combination with 1.25 mM KNO3 (1/8 of the basal) resulted in higher lipid content (341.1 mg g−1 dry cell weight, DCW), but lower biomass (13.12 mgL−1d−1 DCW). The addition of 10.00 mM NaHCO3 to such cultures enhanced not only lipid content to 1.17-fold but also biomass productivity to 2.25-fold. The increase in biomass may be correlated with the stress-ameliorating effects of bicarbonate augmentation which helped in maintaining the health of the cells, as reflected by robust photosynthetic performance. The two important enzymes, RuBisCO and ACCase were also monitored for their expressions. RuBisCO possesses large and small subunits (rbcL and rbcS) responsible for incorporation of CO2, and beta carboxyl transferase (accD) of the heteromeric ACCase is associated with the first and committed step of fatty acid biosynthesis. Enhanced biomass and lipid content in D. salina cells after NaHCO3 augmentation may be ascribed to 6.23-fold increase in the expression of accD and > 2.16-fold increase in rbcL and rbcS genes. Thus, the present work recommends a threshold level of nitrogen and bicarbonate in phosphate deficient D. salina cultures for simultaneously maximizing the biomass and lipid content. [ABSTRACT FROM AUTHOR]

Spinâ€"orbit interaction deals with the interaction and coupling of spin and orbital angular momentum degrees of freedom of spinning particles, which manifests in diverse fields of physics, ranging from atomic, condensed matter to optical systems. In classical light beams, this has led to a number of non-trivial optical phenomena like spin and orbital Hall effect of light, optical Rashba effect, photonic Aharonovâ€"Bohm effect, rotational Doppler effect, transverse spin, Belinfante’s spin-momentum and spin-momentum locking etc. These have been observed in diverse micro- and nano-scale optical systems. These have generated a new area in photonics, namely, spin-orbit photonics that not only deals with fundamental lightâ€"matter interaction effects but also opened up the feasibility of a new generation of miniaturized and on-chip integrable multifunctional photonic devices based on the angular momentum and geometrical phase of light. This paper will introduce the emerging field of spin-orbit photonics and will cover the representative spin-orbit photonic effects in a variety of light-matter interactions with examples. In this regard, we also present proof-of-concept demonstrations of two interesting techniques based on the geometrical phase of light, namely, geometrical phase polarimeter and weak value polarimeter. [ABSTRACT FROM AUTHOR]

[Display omitted] • Review provides an overview of hybrid nanomaterials-based biosensors for detection of various cancer biomarkers. • Biosensors have been widely used for detection of cancer biomarkers. • Immobilization of cancer biomarker on desired electrode is still a challenge. • Sample preparation for detection of cancer cells needs to be simplified. • Biological, technical and clinical challenges in cancer biomarker detections. Early detection and diagnostics are essential for the cure of cancer which has high mortality rate globally. In recent decades, various methods such as mammography, computed tomography (CT) scan, magnetic resonance imaging (MRI), polymerase chain reaction (PCR), molecular imaging, endoscopy and electrochemical methods have been adopted to detect cancerous cells. All of the above-mentioned techniques have their own pros and cons, hence, there is a need of reliable and sensitive tool for pre diagnostics of cancer biomarkers. To overcome various drawbacks of traditional methods, nanotechnologies emerged out to be highly advantageous for early cancer diagnostics by detecting cancer biomarkers in their lower limits. Electrochemical biosensors are very useful tools due to their small size, portability, easy to use, requirement of small sample volume and cost effectiveness. Electrochemical biosensors can also detect low levels of target cancer biomarkers in biological fluids. Further, the use of nanomaterials in electrochemical biosensor provides high surface area, good biocompatibility, high electrical conductivity, low cost and fast analysis. Therefore, electrochemical nanobiosensors are getting increased attention for the early detection of cancer biomarkers in clinical medicines. In this review, recent advancements made in last decade (2011–2021) and modifications made in the field of electrochemical biosensors on integrating with nanoscale materials-based hybrid frameworks have been reviewed. The application of electrochemical techniques and their detection modes in cancer biomarkers detection has been focused. Further, biological, technical and clinical challenges as well as future outlook have been also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Hexagonal aluminum nitride (AlN) whiskers have been synthesized at 1873K under a flowing nitrogen atmosphere. The synthesized whiskers are long straight filaments with diameters between 1 and 5μm and length in the cm range. In order to investigate its “oxidation resistance”, a series of experiments have been performed. The oxidation behavior was quite different in the experimental temperature range assigned, which can be attributed to the kinetic factor and the morphological development during oxidation process. It was chemical controlled at lower temperature while both chemical reaction and diffusion controlled at medium temperature. Further accelerating of temperature to 1473K, AlN whiskers was peeled into smaller parts, which increased the oxidation rate and hence showed powder-like oxidation behavior. Our new kinetic theory has been applied to study the oxidation behavior of AlN whiskers. The comparison of the experimental data with the theoretical ones validates the applicability of the new model. [Copyright &y& Elsevier]

[Display omitted] • Coordination compounds have played significant roles in developing novel derivatives with therapeutic purposes. • Establishing coordination compounds is an excellent option for targeting various diseases such as microbial, viral, cancer, and diabetes. • Many structural perspectives and biological impacts have been canvased for coordination compounds in this review. Coordination compounds-based drugs are crucial in targeting various diseases due to their distinct structural order. They also show a significant role in biological systems, including human beings. For example, hemoglobin, a carrier of oxygen transportation in the blood, is a metal complex of Fe (II) ions and is vital for human life. In addition, they have been utilized for treating various diseases associated with human beings due to their excellent anti-bacterial, anti-cancer, and anti-viral potential. The coordination compounds of different metal ions such as platinum (Pt), palladium (Pd), ruthenium (Ru), nickel (Ni), chromium (Cr), silver (Ag), and gold (Au) have been used as anti-cancer drugs. Moreover, the metal complex of chromium, gold, and copper ions exhibited excellent anti-bacterial activity. Additionally, many coordination compounds revealed promising applications against malaria and neurodegenerative diseases like Alzheimer's. Recently, coordination compounds have been utilized as anti-viral drugs to treat coronavirus. In the present review, we have spotlighted the advanced and most significant coordination compounds that exhibit an essential role in medicine. [ABSTRACT FROM AUTHOR]