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The potential for DNA damage and the activation of specific oncogenic pathways that cause inflammation are present in a wide range of physical, chemical, and biological variables that are constantly present in human beings. According to certain theories, chemical carcinogens are the primary etiological factor in cancer. These substances interact either or non-covalently with the DNA, RNA, and proteins in human tissue, which helps to initiate carcinogenesis, a process in which genetic mutation and changes to the transcription of the genome take precedence. These carcinogens act as cancer cell growth initiators or promoters. When DNA, RNA, or proteins are alkylated, covalent connections are first formed with them and then the promoting action occurs. The process involves numerous molecular and cellular changes that turn normal cells into plastic cells. Although it is hypothesized that these endogenous chemical processes could cause DNA damage by inducing gene changes with the aid of reactive oxygen species. This review's focus is on the basic mechanism and metabolism of chemical carcinogenesis. Chemical carcinogens are supposedly considered to be the key etiological factor of malignancy. The covalent or non-covalent bonds between these chemical and the DNA, RNA, and proteins of human tissue help in the initiation of carcinogenesis wherein, genetic mutation and alteration in the genome transcription supervenes. These carcinogens behave as initiators or promoters of cancer cell growth. Alkylation of DNA, RNA, or proteins and the formation of covalent bonds with them begin initially followed by the promoting effect. Numerous molecular and cellular events causing the transformation of normal cells into neoplastic cells occur in the process. It is assumed though those endogenous molecular pathways could instigate mutations in respective genes with the support of reactive oxygen species, thus leading to DNA damage. Thus, this review deals with the basic mechanism and metabolism of chemical carcinogenesis.

The most popular Indian spice is the seed of Foeniculum vulgare. It is extensively grown in temperate and tropical areas of the world for its flavorful fruits, which are used in cooking. It is a good source of calcium, vitamins, iron, magnesium, dietary fibre, proteins, and other nutrients. Additionally, it has antibacterial, antioxidant, and anti-inflammatory properties. The objective of this study was to evaluate the phytoconstituents of Foeniculum vulgare seed extract in various solvents and to ascertain the antibacterial activity of the hydro-methanolic extract of Foeniculum vulgare seed against gram-positive bacteria, including Bacillus subtilis, Staphylococcus aureus, and Enterococcus, as well as gram negative bacteria, including P. aeruginosa, K. pneumoniae, and E. coli. The antibacterial activity was assessed using agar disc diffusion methods, and phytochemical tests were based on visual observation of the change in colour or precipitate development with the addition of particular reagents. According to the findings, gram positive and gram negative bacteria are both susceptible to the antibacterial effects of a methanolic extract of Foeniculum vulgare seed. We came to the conclusion that the Foeniculum vulgare seed extract has potent antibacterial activity against food-borne pathogens, making it useful for everyday use in the food and pharmaceutical industries as well as for everyday life.

Herbal resources are useful for traditional medicine, folk medicine, modern medicine, nutraceuticals, dietary supplements, pharmaceutical intermediates, and chemical precursors for synthetic drugs. The antibacterial qualities of the leaves of piper betel, also known as paan, have long been employed in Indian traditional medicine. A methanol extract of Piper betel leaves was examined for its ability to inhibit the growth of Bacillus subtilis, Bacillus cereus, Bacillus frimicutes, Escherichia coli, Entrobacter, Klebsiella, and other bacteria (both gram-positive and gram-negative bacteria).The extract of Piper betel leaves also contained proteins, glycosides, alkaloids, flavonoids, terpenoids, tannins, fixed oil, and lipids. The antibacterial activity was evaluated using the agar disc diffusion method. The outcomes shown that the antibacterial properties of Piper betel Linn's limit the growth of microorganisms in a dose-dependent manner. The outcomes demonstrate that the extract from Piper betel possesses antibacterial activity in the tested system. Secondary metabolites are thought to be produced by this plant. The results also imply that favorable results can emerge from habitually using herbs with historical efficacy claims in scientific study.

Samples of boron (B) doped g-C3N4 (BCN) and boron nitride (BN) composite (BN/BCN) were synthesized by a simple in situ technique by varying BN content in the range of 1–10% mass fraction and boron contents are crucial for improving the activity of the composites. The composites were characterized by PXRD and FTIR in order to confirm their successful formation. Prompt Gamma Neutron Activation Analysis (PGNAA) using thermal neutron beam from Dhruva reactor was used for non-destructive determination of total boron concentration by measuring 478 keV prompt gamma-ray from 10B (n, αγ)7*Li reaction. The obtained boron concentrations are in the range of 2.3–6.2% mass fraction.

An external particle induced gamma-ray emission (in air) PIGE facility has been set up for the first time at FOTIA, BARC for rapid and non-destructive quantification of low Z elements. Proton beam of energy of 3.5 MeV was obtained on the target using a 25 μm Tantalum window and Ta collimator of 5 mm diameter. The in situ current normalized PIGE method was validated by quantifying low Z elements in a mixed synthetic standard and in two (certified / standard) reference materials namely USGS CRM G2 and NIST SRM 620. The external PIGE method was applied to lithium-based ceramics, boron carbide and soda-lime and borosilicate glass samples for quantification of low Z elements.

A Prompt Gamma-ray Neutron Activation Analysis (PGNAA) facility was set up using a thermal neutron beam at Dhruva research reactor. It was utilized for non-destructive quantification of total boron in refractory neutron absorbers and 10B atom% in B4C ceramics having natural and enriched 10B composition by measuring the 478 keV prompt gamma-ray from 10B(n,αγ)*7Li. Self-shielding correction was carried out for higher boron concentration samples using chlorine as an internal standard. As a part of quality assurance, the results of PGNAA were compared with those obtained by in situ current normalized Particle Induced Gamma-ray Emission (PIGE) method.

We present a comparative study of different modeling approaches to the electronic properties of the $\textrm{Hf}_{0.05}\textrm{Nb}_{0.05}\textrm{Ta}_{0.8}\textrm{Ti}_{0.05}\textrm{Zr}_{0.05}$ high entropy alloy. Common to our modeling is the methodology to compute the one-particle Green's function in the framework of density functional theory. We demonstrate that the special quasi-random structures modeling and the supercell, i.e. the locally self-consistent multiple-scatering methods provide very similar results for the ground state properties such as the spectral function (density of states) and the equilibrium lattice parameter. To reconcile the multiple-scattering single-site coherent potential approximation with the real space supercell methods, we included the effect of screening of the net charges of the alloy components. Based on the analysis of the total energy and spectral functions computed within the density functional theory, we found no signature for the long-range or local magnetic moments formation in the $\textrm{Hf}_{0.05}\textrm{Nb}_{0.05}\textrm{Ta}_{0.8}\textrm{Ti}_{0.05}\textrm{Zr}_{0.05}$ high entropy alloy, instead we find possible superconductivity below $\sim 9$K.

We describe the performance of the Boolardy Engineering Test Array (BETA), the prototype for the Australian Square Kilometre Array Pathfinder telescope ASKAP. BETA is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarization beams. We report the methods developed for forming and measuring the beams, and the adaptations that have been made to the traditional calibration and imaging procedures in order to allow BETA to function as a multi-beam aperture synthesis telescope. We describe the commissioning of the instrument and present details of BETA's performance: sensitivity, beam characteristics, polarimetric properties and image quality. We summarise the astronomical science that it has produced and draw lessons from operating BETA that will be relevant to the commissioning and operation of the final ASKAP telescope., Accepted for publication in PASA

The Variables and Slow Transients Survey (VAST) on the Australian Square Kilometre Array Pathfinder (ASKAP) is designed to detect highly variable and transient radio sources on timescales from 5 s to$\sim\!5$yr. In this paper, we present the survey description, observation strategy and initial results from the VAST Phase I Pilot Survey. This pilot survey consists of$\sim\!162$h of observations conducted at a central frequency of 888 MHz between 2019 August and 2020 August, with a typical rms sensitivity of$0.24\ \mathrm{mJy\ beam}^{-1}$and angular resolution of$12-20$arcseconds. There are 113 fields, each of which was observed for 12 min integration time, with between 5 and 13 repeats, with cadences between 1 day and 8 months. The total area of the pilot survey footprint is 5 131 square degrees, covering six distinct regions of the sky. An initial search of two of these regions, totalling 1 646 square degrees, revealed 28 highly variable and/or transient sources. Seven of these are known pulsars, including the millisecond pulsar J2039–5617. Another seven are stars, four of which have no previously reported radio detection (SCR J0533–4257, LEHPM 2-783, UCAC3 89–412162 and 2MASS J22414436–6119311). Of the remaining 14 sources, two are active galactic nuclei, six are associated with galaxies and the other six have no multi-wavelength counterparts and are yet to be identified.

The in situ current normalized particle induced gamma-ray emission method using 4 MeV proton beam was utilized for total boron concentrations in boron based neutron absorbers and borated wood based neutron shielding materials. Boron carbide samples with varying masses were analyzed to examine the effect of matrix as well as the efficacy of the in situ current normalized method. Isotopic composition of boron (10B/11B atom ratio) has been determined in natural and 10B enriched boron carbide samples as well as in four synthetically prepared enriched boron carbide samples to serve as in-house reference standard for isotopic composition.