Evaluating the performance of electrocoagulation system in the removal of polystyrene microplastics from water.

Emerging pollutants, particularly microplastics, present a significant threat to both the environment and human health. Traditional treatment methods lack targeted strategies for their removal. This study thoroughly investigated the efficacy of electrocoagulation as a method for efficiently extracting microplastics from water. Various critical operational parameters, including electrode combinations, pH levels, electrolyte concentrations, electrode geometries, configurations, current intensities, and reaction times, were systematically examined. The study systematically examined the impact of different combinations of aluminium (Al) and stainless steel (SS) electrodes, including Al-Al, SS-SS, Al-SS, and SS-Al. Among these combinations, it was found that the Al-Al pairing exhibited outstanding efficiency in microplastic removal, while simultaneously minimizing energy consumption. Initial pH emerged as a critical parameter, with a neutral pH of 7 demonstrating the highest removal efficiency. In the pursuit of optimizing parameters like electrolyte concentrations, electrode geometry, and configuration, it's noteworthy that consistently achieving removal efficiencies exceeding 90% has been a significant achievement. However, to ascertain economic efficiency, additional factors such as energy consumption, electrode usage, and post-treatment conductivity must be taken into account. To tackle the complexity posed by various parameters and criteria, using multi-criteria decision-making tools like TOPSIS is essential, as it has a track record of effectiveness in practical applications. The electrolyte concentration of 0.5 g L-1 is identified as optimal by TOPSIS analysis Additionally, the TOPSIS highlighted the superiority of cylindrical hollow wire mesh electrodes and established the monopolar parallel configuration as the most effective electrode connection method. The investigation carefully evaluated the effect of reaction time, determining that a 50-min window provides optimal microplastic removal efficiency. This refined system exhibited remarkable proficiency in eliminating microplastics of varying size ranges (0-75 µm, 75-150 µm, and 150-300 µm), achieving removal efficiencies of 90.67%, 93.6%, and 94.6%, respectively, at input concentration of 0.2 g L-1. The present study offers a comprehensive framework for optimizing electrocoagulation parameters, presenting a practical and highly effective strategy to address the critical issue of microplastic contamination in aquatic environments.

Silver-catalyzed synthesis of nitrogen heterocycles: recent advancements.

Heterocyclic chemistry is an ever-expanding field without boundaries. Heterocycles play a significant role in medicinal and pharmaceutical chemistry, the agricultural industry and materials science. Among heterocycles, N-heterocycles constitute a large family. Their ubiquity in living and non-living systems makes them an endless topic for research. Being a part of the research community, we need to balance environmental concerns with scientific and economic development. So, research that is coherent with nature is a trending domain at all times. Silver catalysis possesses a greener face in organic synthesis. The simple, rich and extensive chemistry shown by silver makes it an attractive choice for catalysis. Inspired by its versatility and uniqueness we have compiled here recent developments in the silver-catalyzed synthesis of nitrogen-containing heterocycles since 2019. The high efficiency, regioselectivity, chemoselectivity, recyclability of the catalytic system, greater atom economy and simple reaction setup are the major highlights of this protocol. It is a hot research topic which is evident from the large number of works carried out for the fabrication of a range of N-heterocycles with varying complexities.

Utilization of thermal neutron induced in-situ chain reactions and the (n,p) reaction with fast neutrons for compositional characterization of lithium titanate.

A methodology has been developed for the complete compositional characterization of lithium titanate (LTO) using neutron activation, which is quite challenging and no literature report is available so far. The concept of thermal neutron induced in-situ chain reactions 6Li(n,α)3H and 16O(3H,n)18F has been used for the determination of Li and O through the measurement of 18F activity. The method is capable of analyzing Li and O in percentage level as reported in the present analysis of two types of lithium titanate samples. Spectroscopic interference of the elements which can directly or indirectly affect the outcome, were evaluated meticulously. Determination of Ti was carried out using fast neutron activation through the product isotopes like 47Sc, 48Sc, generated via (n,p) nuclear reactions. Fast neutron activation methodology seems to be advantageous for Ti determination over thermal neutron activation, as it offers self validation through different isotopes and multiple gamma lines.

Prospective evaluation of EDXRF for studying the cation exchange membrane separation of Co from Zr in oxalic acid media and comparison with radiotracer experiments.

This work focuses on the selective separation of Co from Zr and Nb, for the decontamination of pressure tubes from pressurized heavy water reactor. Initial experiments were carried out using the respective radiotracers. These laboratory scale studies explore the feasibility of using oxalic acid, a benign complexing medium, for the Zr-Nb matrix, with targeted sorption of trace levels of 60Co on cation exchange membranes. Sorption of Co(II) on the membrane followed pseudo second order kinetics and the equilibrium capacity was 1.89 meq g-1. Oxalic acid concentration was a trade-off between the loading of matrix elements and the % sorption of Co(II). Energy dispersive X-ray fluorescence (EDXRF) spectrometry was used for monitoring the sorption of Co on the membrane from inactive sample solutions. Sorption improved the EDXRF detection limits for Co from 50 µg in solution to 1.3 µg on the membrane, where the total concentration of the matrix elements in solution was 50 g L-1. EDXRF method was validated by spike recovery and radiotracer studies.

Novel formulations of Bacillus thuringiensis var. kurstaki: an eco-friendly approach for management of lepidopteran pests.

Bacillus thuringiensis (Bt) and entomopathogenic fungi (EPF) are in use for management of insect pests. Continuous use of Bt can lead to problem of resistance development in insect pests. Hence use of combination formulations (CF) of microbials with diverse modes of action has been attempted to slow down the process of resistance development. Suspension concentrate (SC) formulations of a local strain of Bt var. kurstaki DOR Bt-127 were developed singly and in combination with conidia of the EPF Nomuraea rileyi (Nr) and Beauveria bassiana (Bb). Electron microscopy of Bt + Bb CF treated larvae of Helicoverpa armigera revealed simultaneous infection by both microbials indicating their compatibility. Endotoxin contents in Bt-SC, Bt + Bb and Bt + Nr CFs were 5.0, 4.7 and 4.7%, respectively. These formulations were effective against larvae of Spodoptera litura, H. armigera and Achaea janata coupled with a lowering of the effective requirement of Bt and EPF. In multi-location field trials, Bt-SC and Bt + Nr CF were highly effective against S. litura and A. janata on castor as well as H. armigera and Thysanoplusia orichalcea on sunflower. However, Bt + Bb CF was highly effective only on sunflower against H. armigera and T. orichalcea. All formulations had 24 months shelf-life at room temperature. DOR Bt-127 based SC formulations developed singly and in combination with Nr and Bb were effective against major lepidopteran pests of castor and sunflower and did not lose viability under storage at room temperature. The CFs of Bt with EPF could prove promising for mitigating resistance development to Bt.

Effect of different physico-chemical factors on sorption of Pa(V) on iron oxides.

The effects of different physico-chemical parameters on sorption of protactinium (Pa) on three different iron oxides (goethite, hematite and magnetite) were studied. The sorption of Pa(V) on all the three iron oxides was low at pH 1, increased to ~ 90% at neutral pH and then decreased slightly above pH 9. Presence of humic acid increases the sorption of Pa(V) on iron oxides in acidic medium whereas sorption is reduced in basic medium. The classical methods like ionic strength, time and temperature dependent sorption studies have been used for the elucidation of the sorption mechanism of Pa(V) on iron oxides. Physisorption in acidic pH and chemisorption in basic pH are the most probable mechanisms. The study demonstrates that classical method alone can be used for the sorption mechanism investigations in the circumstances where it is difficult to have spectroscopic evidences.

Sorption of Nb(V) on pyrolusite (ß-MnO2): Effect of pH, humic acid, ionic strength, equilibration time and temperature.

The sorption of Nb(V) on pyrolusite has been studied and the effect of pH, ionic strength, humic acid, temperature and equilibration time were also investigated in a series of batch equilibrium experiments. The sorption was found to be affected by solution pH, ionic strength and humic acid. The sorption was high in neutral/near neutral pH (~96 %) but lower sorption was observed both in acidic (~55 %) and basic (~85 %) media. Sorption was decreased in acidic pH with increase of ionic strength and reverse effect was seen in basic pH although the effect is less prominent. Presence of humic acid causes enhancement of sorption in acidic pH whereas sorption declined in basic pH. The sorption process is endothermic in acid medium and exothermic in basic medium. In acid medium the sorption is entropy driven process. Kinetics of the sorption study was found to follow pseudo first order in acidic pH whereas pseudo second order in basic pH.

Determination of impurities in graphite using synchrotron radiation based X-ray fluorescence spectrometry.

Determination of impurities namely Ca, Mn, Fe, Ni, Zn, Sr and Pb in graphite by energy dispersive X-ray fluorescence spectrometry is described using microfocused synchrotron radiation. The internal standard and standard addition methodologies were adopted for quantification and the results were compared with tube-based X-ray fluorescence spectrometry. Analysis of the results by the F and t-tests revealed their statistical equivalence. Synchrotron measurements improved the detection limits by an order of magnitude compared to the tube based technique. Cr and Zr, which were below the quantification limit in tube based technique, were also quantified by synchrotron based technique.

Characterization and regulation of Bacillus thuringiensis Cry toxin binding aminopeptidases N (APNs) from non-gut visceral tissues, Malpighian tubule and salivary gland: Comparison with midgut-specific APN in the moth Achaea janata.

Bacillus thuringiensis (Bt) crystal proteins (Cry) bind to aminopeptidase N (APN) receptors on insect midgut membrane leading to pore formation and subsequent death. However, evolution of insect resistance to Bt toxins threatens their long-term application. Therefore, search for new targets which could function as Cry toxin receptors is an immediate mandate. In the present study, two full-length APN cDNAs were cloned from Malpighian tubule and salivary gland tissues of the moth, Achaea janata. Both these APNs showed 99% and 32% sequence homology with fat body and midgut APNs respectively. Tissue distribution analysis revealed the presence of two different APN isoforms, one predominant in non-gut visceral tissues while the other exclusively expressed in the midgut. Immunofluorescence and western blot analyses showed cross-reactivity in Malpighian tubule and salivary gland when probed with anti-fat body APN antiserum. These results clearly indicated the presence of non-gut (AjAPN1) and gut-specific (AjAPN4) isoforms in this moth. The expression of both the isoforms steadily increased during the larval development. Hormonal studies indicated regulation of the APN genes by the morphogenetic hormones, 20-hydroxyecdyone and juvenile hormone. Further, in vitro ligand-blotting studies demonstrated binding of Cry toxins to APNs in Malpighian tubule and salivary gland indicating their potential as alternate targets.

Sorption of As(III) and As(V) on chemically synthesized manganese dioxide.

Sorption of As(III) and As(V) on manganese dioxide was studied by batch equilibration method using (76)As radioactive tracer. Manganese dioxide was prepared by two different methods viz. reacting (a) KMnO(4) solution with MnSO(4) solution, and (b) KMnO(4) solution with concentrated hydrochloric acid. Manganese dioxide was characterized by zeta potential measurement, surface area measurement, thermogravimetry (TG), differential thermal analysis (DTA) and X-ray diffraction (XRD) techniques. Point of zero charge (PZC) for manganese dioxide was between pH 3 and 4. Radioactive tracer ((76)As) was prepared by neutron irradiation of arsenious oxide in self serve facility of CIRUS reactor followed by conversion to As(III) and As(V), by appropriate chemical methods. Sorption of As(III) and As(V) were studied separately, between pH 1 to 11, using (i) freshly prepared, (ii) air-dried and (iii) aged manganese dioxide. Sorption of As(III) and As(V) on freshly prepared as well as aged manganese dioxide, from both the methods was greater than 98% between pH 1 to 9 and decreased above pH 9. Percentage sorption was comparable for manganese dioxide prepared by both the methods in different batches. Sorption capacity was ∼2 mg g(-1) for both As(III) and As(V). Arsenic was desorbed from the manganese dioxide by 0.1 M sodium hydroxide and oxidation state of desorbed arsenic was determined by solvent extraction method. It was found that the desorbed arsenic was present in As(V) oxidation state, independent of the initial oxidation states. This simple and direct chemical evidence, establishing that As(III) is converted to As(V) by manganese dioxide, is reported for the first time. Sorption of As(III) and As(V) on manganese dioxide did not cause an increase in manganese concentration above solubility limit confirming that Mn(2+), formed during oxidation of As(III) to As(V), was re-adsorbed.

Cloning, characterization, and expression of a new cry1Ab gene from DOR Bt-1, an indigenous isolate of Bacillus thuringiensis.

A new cry1Ab gene was cloned from the promising local isolate, DOR Bt-1, a Bacillus thuringiensis strain isolated from castor semilooper (Achaea janata L.) cadavers from castor bean (Ricinus communis L.) field. The nucleotide sequence of the cloned cry1Ab gene indicated that the open reading frame consisted of 3,465 bases encoding a protein of 1,155 amino acid residues with an estimated molecular weight of 130 kDa. Homology comparisons revealed that the deduced amino acid sequence of cry1Ab had a variation of seven amino acid residues compared to those of the known Cry1Ab proteins in the NCBI database and this gene has been designated as cry1Ab26 by the B. thuringiensis δ-endotoxin Nomenclature Committee. cry1Ab26 was cloned into pET 29a(+) vector and expressed in E. coli strain BL21 (DE3) under the control of T7 promoter with IPTG induction. ELISA, SDS-PAGE, and Western blot analysis confirmed the expression of 130-kDa protein. Insect bioassays with neonate larvae of Helicoverpa armigera showed that the partially purified Cry1Ab26 caused 97 % mortality within 5 days of feeding.

Left ectopic kidney with non rotation: a case report.

Congenital anomalies of the urinary tract system are common. The ectopic pelvic kidney is a rare anomaly about 1:2500 live births, left side being more common. Here we are reporting a case of left ectopic kidney with non rotation and morphologically normal right kidney. The case was found during routine dissection in the department of anatomy in an adult male cadaver. There were no other anomalies observed.

Characterization of Bacillus thuringiensis strain DOR4 toxic to castor semilooper Achaea janata: proteolytic processing and binding of toxins to receptors.

We have isolated a strain of Bacillus thuringiensis (Bt) from Indian soil samples that was shown to be toxic to Achaea janata larvae. The isolate, named B. thuringiensis DOR4, serotypically identified with the standard subspecies kurstaki (H3a3b3c) and produced bipyramidal inclusions along with an amorphous type. Although the plasmid pattern of DOR4 was different from that of the reference strain, a crystal protein profile showed the presence of two major bands (130 and 65 kDa) similar to those of Bt subsp. kurstaki HD-1. To verify the cry gene content of DOR4, triplex PCR analysis was performed; it showed amplification of the cry1C gene in addition to cry1Aa, cry1Ac, cry2A, and cry2B genes, but not the cry1Ab gene. RT-PCR analysis showed the expression of cry1Aa and cry1Ac genes. In vitro proteolysis of DOR4 protoxin with midgut extract generated products of different sizes. Zymogram analysis of DOR4 protoxin as substrate pointed to a number of distinct proteases that were responsible for activation of protoxins. Furthermore, toxin overlay analysis revealed the presence of multiple toxin-binding proteins in midgut epithelium. Based on all these characterizations, we suggest that the Bt DOR4 strain can be exploited for an A. janata control program.

Cost-effective production of Bacillus thuringiensis by solid-state fermentation.

Production of Bacillus thuringiensis (Bt) was standardized on wheat bran based media in 250 ml Erlenmeyer flasks. Scale-up of Bt production on the best medium in plastic tubs with aeration at 8 h intervals starting 16 h after incubation yielded a significant increase in spore count and toxin content of the product. Maximum lysis of Bt cells was obtained by 60 h of incubation at 30 degrees C. This protocol was suitable for production of Bt strains and local isolates. The Bt produced proved highly effective at 0.1% concentration against larvae of castor semilooper, Achaea janata L, resulting in complete mortality by three days in laboratory bioassays. In field trials, the population of castor semilooper larvae on the castor bean crop was reduced significantly by three days after application. The cost for material production of 1 kg of Bt was approximately US dollars 0.70.

Identification of virulent isolates of the entomopathogenic fungus Nomuraea rileyi (F) Samson for the management of Helicoverpa armigera and Spodoptera litura (identification of virulent isolates of N. rileyi).

Eleven geographical isolates of the entomopathogenic fungus Nomuraea rileyi (Farlow) Samson of Helicoverpa armigera (Hubner)/Spodoptera litura (Fabricius) origin were studied for efficacy against the two host insects. Laboratory bioassays at a concentration of 2 x 10(8) conidia ml(-1) indicated that N. rileyi isolates of S. litura origin were better in terms of time taken for mycosis and mortality in both the test larvae: S. litura (77-80% mortality in 7 days) and H. armigera (79-85% in 8 days). Among the isolates of S. litura origin, geographical isolates from Hyderabad and Karimnagar were superior in terms of high percent kill as well as 100% germination of conidia within 48 h. Fastest germination was observed with Karimnagar isolate followed by Hyderabad isolate. Conidial yield was highest on barley-carrot extract-yeast extract medium. However in terms of material cost, barley-yeast extract medium was the lowest. The Karimnagar isolate of S. litura origin gave the highest conidial yield on barley-yeast extract medium. Chitinolytic enzyme profiles of different isolates revealed polymorphism in all the isolates from S. litura origin. Overall among the parameters studied the best traits were found in the Karimnagar isolate of S. litura origin.

Cost-effective multiplication of the entomopathogenic fungus Nomuraea rileyi (F) Samson.

Cost-effective and rapid multiplication of Nomuraea rileyi is reported. The spore yields in semi-synthetic media were comparable or significantly higher to the standard medium. Maltose and peptone, carbon and nitrogen sources could be effectively replaced with 2% barley extract and 1% soybean extract respectively. However, replacement of yeast extract with dry yeast resulted in lower spore yields. Sporulation of the fungus multiplied on solid substrate was possible only when the bags used had a 0.2 microm filter to facilitate passive exchange of sterile air. A high spore yield of 2.8 x 10(9)/g of substrate was realized on crushed sorghum.

Cell mediated immune responses in BCG vaccinated children.

The immunological status of BCG vaccinated and unvaccinated healthy children was evaluated to assess the efficacy of BCG. The duration of immunity conferred by the vaccine was also investigated. Of the 326 children studied, 170 (52%) had the BCG scar and only 24 (14%) showed a positive Mantoux response. Among the unvaccinated group, 14 of 156 (9%) showed a positive response. All cases had normal proportions of T and B cells in the peripheral blood. The mean values of the leukocyte migration inhibition (LMI) test with PHA were also normal. The per cent LMI values against PPD were compared in the children classified into groups based on their vaccination status and response to Mantoux test. A higher number of the vaccinated children had positive LMI values compared to those unvaccinated (p < 0.01). The LMI values of children classified into three age groups decreased significantly (p < 0.01) with increase in age. Hence, BCG seems to afford some protection in children and has to be administered at birth. Revaccination at the age of eight years, may boost the waning immunity and, may be considered in this age-group.

A modified approach to identification of the sickle cell anemia mutation by means of allele-specific polymerase chain reaction.

The allele-specific PCR approach has been modified by introducing a second mismatch at the 3'-penultimate link of the primer and used to identify the sickle cell anemia mutation (A-->T transversion in the sixth codon of the human beta-globin gene causing Glu-->Val substitution in the protein), thus obviating the problem of an interpretationally ambiguous 3'-terminal mismatch including T residue.

Evaluation of the anti-inflammatory drug indomethacin, for its genotoxicity in mice.

Indomethacin, a non-steroidal anti-inflammatory drug was assessed for its genotoxicity in Swiss male mice employing bone marrow micronucleus induction, abnormal sperm formation and the induction of meiotic chromosome anomalies in spermatocytes as the test parameters. The results showed that the test compound was toxic to the genetic material in the dose range of 12-36 mg/kg body weight.