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Leaf ontogeny of tropical evergreen tree species lasts several months with changes in size, shape, colouration and internal tissue distribution of leaves. Leaf initiation in Saraca asoca generally occurs once in a year during February–April, followed by very limited leafing thereafter. We measured the rate of photosynthesis, chlorophyll a fluorescence, energy quenching and PSII functions during the leaf ontogeny process. Observations were taken up to 35 days after opening of lamina (DAOL). Significant increase in the synthesis and accumulation of photosynthetic pigments but negative net photosynthesis was noticed during initial days of the ontogeny. The leaf moved from heterotrophy to autotrophy with gradual improvement of PSII functions. The ratio of intercellular CO2 (C i) and ambient CO2 (C a) showed significant change at ≥11 DAOL. Increase in the age of the leaf (between 5 and 28 DAOL) caused decrease in O-J rise and corresponding increase in J-I and I-P rise as well as of fluorescence maximum (F M) of the OJIP curve. The improvement of the electron transport components of the donor side of PSII was seen with increase in the functional oxygen evolving complex. The functional improvements of the donor and acceptor side of PSII during leaf ontogeny are discussed. The leaf ontogeny in Saraca asoca usually occurs once in a year and involves variation in PSII function. The developing leaves metabolically switch from heterotrophy to autotrophy. During leaf development, the carotenoids are accumulated earlier than chlorophylls. With the development of leaf, the PSII function improves leading to increased efficiency of oxygen evolving complex and photoelectron transport. [ABSTRACT FROM AUTHOR]

Mycotoxins are toxic secondary metabolites produced by certain molds and fungi that contaminate various food commodities, posing serious adverse effects on humans and animals. Aflatoxin, ochratoxin, trichothecene, fumonisin, zearalenone, patulin, and citrinin are some of the major mycotoxins affecting food and feed. The scientific community has focused on regulating food and feed materials due to their potential risks. Conventional techniques for mycotoxin detection have certain limitations in terms of sensitivity, specificity, and speed. In recent years, nanotechnology has emerged as a promising approach to revolutionize mycotoxin detection. This review provides an overview of nanotechnology‐based detection methods for mycotoxins in food and feed, discussing the basic aspects of mycotoxins, their health hazards, and conventional methods. It also explores various nanosensors and nanodevices developed to improve the sensitivity, selectivity, and speed of mycotoxin detection, thereby enhancing food safety and security. [ABSTRACT FROM AUTHOR]

Insecticides are widely used in agriculture, horticulture, medicine, and industry, as well as domestically. Increased insecticide application has been attributed to higher agricultural productivity and lower infield and postharvest crop loss in the twentieth century. Malathion is a very commonly used organophosphorus (OP) insecticide applied in over 100 food crops in agriculture and post-harvest storage. Different species of Aspergillus have shown their efficiency to degrade OP chemicals. A malathion tolerant Aspergillus niger MRU01, developed by prolonged malathion exposure, was tested for its efficiency to remove malathion as well as three other commonly used OP insecticides, viz., parathion, chlorpyrifos and dimethoate. The tolerant strain showed growth efficiency as well as enhanced production of phosphatases and esterase enzyme as compared to untreated and treated wild type (A. niger ATCC16404). The removal of malathion was 29% and 68%, in the wild type and the tolerant strain, respectively during five days. The tolerant strain was also able to remove dimethoate (63%) and chlorpyrifos (54%) with high efficiency while a low rate of removal of parathion (33%) was observed. The strain can be tested in the microcosms more specifically for bioremediation of other OP insecticides before its application in the field. The malathion tolerant Aspergillus niger MRU01 grew efficiently in the presence of 500 μM malathion. Treatment of the fungus with malathion and other OP insecticides – parathion, chlorpyrifos, and dimethoate – caused enhanced expression of phosphatases and esterases. The tolerant A. niger MRU01 strain had significantly lower mycelia concentrations of insecticides than of the wild type A. niger ATCC16404. Degradation of insecticides by the tolerant strain was significantly higher than by the wild type indicating its broad spectrum of tolerance. [ABSTRACT FROM AUTHOR]

This paper introduces 'Inclusive Integrativeness' as a novel approach to address ESL classroom challenges, focusing on learners' diverse linguistic backgrounds. Unlike traditional integrativeness, which aims for assimilation into the target language and culture, this approach embraces multilingual identities. In multilingual regions like Assam, India, it emphasizes the importance of learners' reflexivity on their linguistic repertoire to develop an inclusive multilingual identity. The study also advocates for classroom practices such as translanguaging and culturally relevant materials. A survey of 105 secondary school students in Assam revealed positive perceptions towards inclusive multilingual identity and the use of these practices. The findings support 'Inclusive Integrativeness' as a comprehensive pedagogical approach for integrating multilingualism and English proficiency in ESL education. [ABSTRACT FROM AUTHOR]

Hypericum perforatum L., commonly known as St. John's wort is an important medicinal plant, belonging to family Hypericaceae. Among all species of Hypericum, H. perforatum is most investigated and exploited. It is sold as one of the world's topmost retailing antidepressants. This plant possesses antibacterial, antiviral, anti-inflammatory, and anticancerous properties. These medicinal properties are attributed to the presence of bioactive compounds, such as hypericins and pseudohypericins (naphthodianthrones), hyperforin and adhyperforin (prenylated acylphloroglucinols), quercetin, rutin, isoquercetin, and catechin (flavonoids), chlorogenic acid, caffeic acid, and tannic acid (phenols) and xanthones. The conventional methods of propagation of H. perforatum are time consuming and field grown plants are exposed to biotic and abiotic challenges which affect its phytochemical constituents. Moreover, these methods are also unable to meet the commercial demand of secondary metabolites. Therefore, in order to meet the growing raw material demand of pharmaceutical industries there is a need to develop effecient in vitro plant regeneration protocols for large scale production of H. perforatum plants and other biotechnological methods (cell, tissue and organ culture, cell suspension culture, hairy root culture, elicitation, etc.) for improvement of target bioactive compounds. The present review provides a comprehensive account of the available information on in vitro plant regeneration and biotechnological approaches used to enhance the secondary metabolite(s) content in H. perforatum during the past years. It also deals with the unexplored areas which might be exploited for drug discovery. [ABSTRACT FROM AUTHOR]

Anterior mediastinal teratoma can externally compress the pulmonary artery, which can present with symptoms of pulmonary stenosis rarely. We have reported a case of a 47-year-old male with immature mediastinal teratoma presenting as pulmonary stenosis. Initial physical examination revealed an ejection systolic murmur in the pulmonary area. With suspicion of valvular heart disease, the patient was referred to our cardiology department. Chest X-ray shows mass just above the left hilar zone. Two-dimensional echocardiography shows a mediastinal mass compressing the pulmonary trunk causing an obstruction. Contrast-enhanced computed tomography of thorax and magnetic resonance study confirmed the mediastinal mass. Fine-needle aspiration cytology of the mass suggestive of immature teratoma. The patient was transferred to the cardiothoracic vascular surgery department for further management. Mediastinal mass can mimic valvular heart disease with symptoms of cardiovascular pathology. Proper investigations for diagnostic clarity and prompt management are crucial in these conditions. [ABSTRACT FROM AUTHOR]

The exchange of CO2 between the air–water interfaces of estuaries is crucial from the perspective of the global carbon cycle and climate change feedback. In this regard, we evaluated the air–water CO2 exchanges in two major estuaries—the Mahanadi estuary (ME) and the Dhamra estuary (DE) in the northern part of the Bay of Bengal, India. Biogeochemical properties of these estuarine waters were quantified in three distinct seasons, namely, pre-monsoon (March to May), monsoon (June to October), and post-monsoon (November to February). The significant properties of water, such as the water temperature, pH, salinity, nutrients, dissolved oxygen, chlorophyll-a (chl a), and photosynthetic pigment fluorescence of phytoplankton, were estimated and correlated with CO2 fluxes. We found that the ME acted as a source of CO2 fluxes in the monsoon and post-monsoon, while DE acted as a sink during the monsoon. The stepwise regression model showed that the fluxes were primarily driven by water temperature, pH, and salinity, and they correlated well with the phytoplankton characteristics. The chl a content, fluorescence yield, and phycobilisomes-to-photosystem II fluorescence ratios were major drivers of the fluxes. Therefore, for predicting air–water CO2 exchanges precisely in a large area over a seasonal and annual scale in the estuaries of the Bay of Bengal, India, critical key parameters such as water temperature, pH, salinity, chl a, and fluorescence yield of phytoplankton should be taken into consideration. However, the responses of phytoplankton, both in terms of production and CO2 capture, are critical research areas for a better understanding of air–water CO2 exchanges in coastal ecology under climate change scenarios. [ABSTRACT FROM AUTHOR]

BACKGROUND: Microbial degradation of organophosphorus (OP) insecticides has emerged as an efficient and cost‐effective technology for removal of pesticide residues from soil. Malathion‐tolerant Aspergillus (Aspergillus niger MRU01) was developed, mass cultured, harvested, mixed with coir pith at 3% on dry weight basis, shade‐dried aseptically to a 5% moisture level and stored for 60 days. The growth, metabolic activity and insecticide removal efficiencies of the preparation were evaluated at 15‐day intervals. RESULTS: No significant change in the growth performance was observed up to 45 days of storage, after which viability decreased. The activities of carbohydrate enzymes (cellulase, invertase and amylase) and protein and carbohydrate contents of the preparation, however, did not significantly change during the experimental period. The preparation showed accelerated activities of esterases and phosphatases after treatment with malathion (500 μmol L−1), parathion (470 μmol L−1), chlorpyrifos (260 μmol L−1) and dimethoate (680 μmol L−1). The highest activity of the esterase and phosphatase enzymes was observed with malathion and the minimum with parathion treatment. Nearly 70% of the applied malathion was removed from the medium by the preparation during 5 days of incubation followed by dimethoate (68%), chlorpyrifos (58%) and parathion (54%). CONCLUSIONS: The fungal preparation was highly effective in removing malathion as well as the other three OP insecticides. A storage period of 45 days may be considered ideal for maintaining the preparation in the active state, and is recommended for field application after evaluating its efficacy under field conditions. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]