Comparative bioactivity assessment of bixin pigment and associated phytochemicals extracted from annatto seeds using conventional and green solvents.

Nutraceuticals, that include food ingredients and bioactives from natural products, confer physiological health benefits and protection against chronic diseases. Annatto is a tropical shrub grown in Central and South America and parts of India. Its seeds are rich in the edible carotenoid-derived apocarotenoid pigment, bixin, which is used as a natural colorant in food, textiles, and cosmetics, and is now gaining attention for its potential health-promoting attributes. Here, we compared a green solvent (ethyl lactate) based extraction of bixin and associated metabolites in annatto seeds (crushed and seed coat) with two other conventional solvents (acetone and acid-base). Bixin was characterized in the extracts using UV-visible- and FTIR-spectroscopy and thin-layer chromatography. The bixin-containing solvent extracts were then profiled for other co-existing metabolites using GC-MS analysis, which were found to be sesquiterpenes, terpenes, terpenoids, phytosterols, and tocotrienols. Their bioactivity was evaluated based on antioxidant and wound-healing efficacies and compared with pure bixin, using NIH-3T3 fibroblast cells in-vitro. Pure bixin, as well as the annatto solvent extracts, showed strong antioxidant and wound healing properties, wherein pure bixin and green solvent extract (ethyl lactate coat) exhibited higher levels of antioxidant activity, achieving 46.00% and 44.60% reduction in MDA levels, respectively, as well as enhanced wound-healing activity, with 54.09% and 53.60% wound closure within 24 h. The green solvent extracts of annatto seeds revealed: (a) differential bioactive profiles in annatto seeds (crushed and seed coat) in comparison with other solvents, and (b) strong antioxidant and wound healing properties. Thus, ethyl lactate extraction shows strong potential for sustainable environmental friendly production of functional foods/nutraceuticals from annatto seeds.

Multielectron Redox Afforded by a Pincer Ligand Promoting Kumada Cross-Coupling Reactions.

The redox-active nature of a pincer has been exploited to conduct C-C cross-coupling reactions under mild conditions. A nickel complex with a NNN pincer was dimeric in the solid state, and the structure displayed a Ni2 N2 diamond core. In the dimeric structure, both ligand backbones house an electron, in the iminosemiquinonate form, to keep the metal's oxidation state at +2. In the presence of an aryl Grignard reagent, only 3 mol % loading the nickel complex generates a Kumada cross-coupled product in good yield from a wide variety of aryl-X (X= I, Br, Cl) substrates. That the ligand-based radical remains responsible for promoting such a coupling reaction following a radical pathway is suggested by TEMPO quenching. Furthermore, a radical-clock experiment along with tracing product distribution unambiguously supported the radical's involvement through the catalytic cycle. A series of thorough mechanistic probation, including computational DFT analysis, disclosed the cooperative action of both redox-active pincer ligand and the metal centre to drive the reaction.

FPGA: Field programmable gate array-based four-channel embedded system for ultrasonic imaging of under-water concrete structures.

Non-destructive testing is needed for the evaluation of quality and safety of concrete structures in the field of civil engineering. The imaging of concrete/reinforced cement concrete structures (RCC) is a challenging task due to the non-homogeneous properties of the concrete material. To address this challenge, a novel real-time, re-configurable, four-channel embedded system has been designed and developed to image the internal details of the concrete samples using the water immersion pulse-echo (PE) mode under automation, which needs access from one side of the structure. The system performs data acquisition (DAQ) of the amplified echo signals under the control of the computer via a universal serial bus interface. A graphical user interface (GUI) has been developed using C# in a Visual environment, for image acquisition and control of the DAQ parameters. The performance of the system has been evaluated by acquiring B-Scan images of three types of concrete test blocks having side drilled holes (SDHs) and simulated inclusions embedded in concrete blocks of M20 grade using a linear array of 92 kHz water immersion transducers operating in under-water PE mode. The acquired B-Scan images revealed the internal details of the concrete test blocks with sizing of the SDHs and inclusions. Therefore, the developed four-channel ultrasonic imaging system can visualize the internal details of under-water concrete structures, such as bridges and sea links, with the help of corresponding 2-D cross-sectional images, acquired using the developed system.

A sui generis QA approach using RoBERTa for adverse drug event identification.

BACKGROUND: Extraction of adverse drug events from biomedical literature and other textual data is an important component to monitor drug-safety and this has attracted attention of many researchers in healthcare. Existing works are more pivoted around entity-relation extraction using bidirectional long short term memory networks (Bi-LSTM) which does not attain the best feature representations. RESULTS: In this paper, we introduce a question answering framework that exploits the robustness, masking and dynamic attention capabilities of RoBERTa by a technique of domain adaptation and attempt to overcome the aforementioned limitations. With formulation of an end-to-end pipeline, our model outperforms the prior work by 9.53% F1-Score. CONCLUSION: An end-to-end pipeline that leverages state of the art transformer architecture in conjunction with QA approach can bolster the performances of entity-relation extraction tasks in the biomedical domain. In particular, we believe our research would be helpful in identification of potential adverse drug reactions in mono as well as combination therapy related textual data.

Design and development of ultrasonic bipolar square-wave pulser for non-destructive testing of concrete structures.

This paper provides design and development details of the generation of bipolar High Voltage (HV) square wave pulses for the excitation of low frequency ultrasonic transducers. Such a circuit is required for the purpose of ultrasonic inspection of components, particularly where high energy is required to insonify the attenuative medium, such as concrete. A HV (±350 V) square wave pulse has been generated by an ultrafast complementary Metal Oxide Semiconductor Field-Effect Transistor (MOSFET) pair, which is driven by high speed MOSFET drivers. The generated bipolar square wave pulse has been utilized to energize a 108 kHz ultrasonic transducer to operate in the pulse-echo mode for the evaluation of a concrete test block. The receiver amplifier filters the received low-amplitude echo signals, which are reflected back from a discontinuity, and amplifies further for signal to noise ratio enhancement. The pulser board designed has been tested and evaluated for its functionality to measure ultrasonic velocity in the highly attenuative concrete medium up to a depth of 1 m. The measured value of acoustic velocity was compared with the value obtained from the commercially available ultrasonic pulse velocity instrument, and the values obtained are within ±5%.