Remarkable enhancement in radio-cesium uptake from acidic feeds into an extraction chromatography resin containing a calix[4]arene-mono-crown-6 ligand.

An extraction chromatography resin, prepared by the impregnation of bis-octyloxy-calix[4]arene-mono-crown-6 (BOCMC)onto an acrylic ester based polymeric support material, gave excellent uptake data for the removal of radio-cesium (Cs-137) from nitric acid feed solutions. The weight distribution coefficient (Kd) value of >300 obtained during the present study at 3 M HNO3 was the highest reported so far while using a calix-crown-6 based extraction chromatographic resin material. Analogous resin reported previously has yielded a Kd value <100 at comparable feed conditions. The sorbed metal ions could be efficiently desorbed with de-ionized water. Kinetic modeling of the uptake data indicated that both the film and the intra-particle diffusion mechanism are simultaneously operating in the sorption of Cs+ion onto the BOCMC resin. The metal ion sorption data were fitted to the sorption isotherm models and did not conform to the chemisorptions of physisorption models and indicated a pi-pi interaction between the benzene rings of the calix-crown-6 ligand and the Cs+ ion. The reusability of the resins was quite satisfactory after 5 cycles and the radiation stability of the resin material was very good upto an absorbed dose of 500 kGy. The results of column studies were quite encouraging with 15 mL (9 bed volumes) as the breakthrough volume while the elution was complete in about 12 bed volumes of de-ionized water.

Unusual redox stability of pentavalent uranium with hetero-bifunctional phosphonocarboxylate: insight into aqueous speciation.

The +5 state is an unusual oxidation state of uranium due to its instability in the aqueous phase. As a result, gaining information about its aqueous speciation is extremely difficult. The present work is an attempt in that direction and it provides insight into the existence of a new pentavalent species in the presence of hetero-bifunctional phosphonocarboxylate (PC) chelators, other than the carbonate ion, in the aqueous medium. The aqueous chemistry of pentavalent uranium species with three environmentally relevant PCs was probed using electrochemical and DFT methods to understand the redox energy and kinetics of conversion of the U(VI)/U(V) couple, stability, structure, stoichiometry, binding modes, etc. Interestingly, pentavalent uranium complexes with PCs are quite persistent over a wide range of pH starting from acidic to alkaline conditions. The PC chelators block the cation-cation interaction (CCI) of U(V) through strong hetero-bidentate chelation and intermolecular hydrogen bonding (IMHB) interactions which stabilize the pentavalent metal ion against disproportionation. For uranyl species in the presence of PCs, acting as chelators, CV plots were obtained at varying pH values from 2 to 8. The obtained results indicate an irreversible single redox peak involving U(VI) to U(V) conversion and association of a coupled chemical reaction with the electron transfer step. ESI-MS studies were performed to understand the speciation effect on the U(VI)/U(V) redox couple with varying pH. Speciation modelling of U(V) with the PC ligands was carried out, which indicated that the U(V) is redox stable in nearly 47% of the pH region in the presence of the PCs as compared to the carboxylate-based chelators. The free energy and reduction potential of the U(V) complexes and the reduction free energy and disproportionation free energy for the U(VI)/U(V) couple were determined by DFT computations in the presence of the PCs. In situ spectroelectrochemical spectra were recorded to provide evidence for the existence of U(V) species with PCs in the aqueous medium and to acquire its absorption spectra. The present study is highly significant for understanding the coordination chemistry of pentavalent uranium species, accurate modelling of uranium, and isolation of U(V).

Ligand structure and diluent nature in defining improved Am3+ and Cm3+ separation using diglycolamides: a combined solvent extraction and DFT study.

Separation of Am3+ and Cm3+ is one of the most challenging yet unavoidable steps in the back end of the nuclear cycle. Various ligands evaluated for Am/Cm separation have their own merits and demerits, and not a single ligand has been uniquely proposed for this purpose. In the present work, we evaluated N,N,N',N'-tetra-n-octyldiglycolamide (TODGA) vis-à-vis N,N,N',N'-tetra-2-ethylhexyldiglycolamide (T2EHDGA) in combination with a hydrophilic 2,6-bis(1,2,4-triazinyl)pyridine (SO3PhBTP) derivative in the aqueous phase for the separation of Am3+ and Cm3+ from nitric acid medium. The results showed that marginal selectivity for Am3+ over Cm3+ was observed with T2EHDGA in the presence of SO3PhBTP, which was attributed to the difference in the entropy change for their extraction from both the temperature-dependent liquid-liquid extraction and computational studies.

Non-communicable diseases as a major contributor to deaths in 12 tribal districts in India.

Background & objectives: Non-communicable diseases (NCDs) are the leading cause of death in India. Although studies have reported a high prevalence of NCD in tribal populations, there are limited data pertaining mortality due to NCDs. Therefore, in this study we estimated the proportion of deaths due to NCDs among 15 yr and older age group in tribal districts in India. Methods: We conducted a community-based survey in 12 districts (one per State) with more than 50 per cent tribal population. Data were collected using a verbal autopsy tool from the family member of the deceased. The estimated sample size was 452 deaths per district. We obtained the list of deaths for the reference period of one year and updated it during the survey. The cause of death was assigned using the International Classification of Diseases-10 classification and analyzed the proportions of causes of death. The age-standardized death rate (ASRD) was also estimated. Results: We surveyed 5292 deaths among those above 15 years of age. Overall, NCDs accounted for 66 per cent of the deaths, followed by infectious diseases (15%) and injuries (11%). Cardiovascular diseases were the leading cause of death in 10 of the 12 sites. In East Garo Hills (18%) and Lunglei (26%), neoplasms were the leading cause of death. ASRD due to NCD ranged from 426 in Kinnaur to 756 per 100,000 in East Garo Hills. Interpretation & conclusions: The findings of this community-based survey suggested that NCDs were the leading cause of death among the tribal populations in India. It is hence suggested that control of NCDs should be one of the public health priorities for tribal districts in India.

Preparedness of primary & secondary care health facilities for the management of non-communicable diseases in tribal population across 12 districts in India.

Background and objectives: Non-communicable diseases (NCDs) are highly prevalent in the tribal populations; however, there are limited data regarding health system preparedness to tackle NCDs among these populations. We estimated the availability of human resources, equipment, drugs, services and knowledge of doctors for NCD management in the selected tribal districts in India. Methods: A cross-sectional survey was conducted in 12 districts (one from each State) with at least 50 per cent tribal population in Andaman and Nicobar Islands, Himachal Pradesh, Madhya Pradesh, Odisha and eight northeastern States. Primary health centres (PHCs), community health centres (CHCs) and district/sub-district hospitals (DHs) were surveyed and data on screening and treatment services, human resources, equipment, drugs and information systems indicators were collected and analysed. The data were presented as proportions. Results: In the present study 177 facilities were surveyed, including 156 PHCs/CHCs and 21 DHs. DHs and the majority (82-96%) of the PHCs/CHCs provided outpatient treatment for diabetes and hypertension. Overall, 97 per cent of PHCs/CHCs had doctors, and 78 per cent had staff nurses. The availability of digital blood pressure monitors ranged from 35 to 43 per cent, and drugs were either not available or inadequate. Among 213 doctors, three-fourths knew the correct criteria for hypertension diagnosis, and a few correctly reported diabetes diagnosis criteria. Interpretation & conclusions: The results of this study suggest that the health system of the studied tribal districts was not adequately prepared to manage NCDs. The key challenges included inadequately trained workforce and a lack of equipment and drugs. It is suggested that capacity building and, procurement and distribution of equipment, drugs and information systems to track NCD patients should be the key focus areas of national programmes.

Bis-(1,2,4-triazin-3-yl) ligand structure driven selectivity reversal between Am3+ and Cm3+: solvent extraction and DFT studies.

Selectivity between Am3+ and Cm3+ was investigated after their aqueous complexation with three structurally tailored hydrophilic bis-(1,2,4-triazin-3-yl) ligands followed by their extraction with N,N,N'N'-tetraoctyl diglycolamide (TODGA) dissolved in an ionic liquid (C4mim·Tf2N). The three hydrophilic ligands used were SO3PhBTP, SO3PhBTBP, and SO3PhBTPhen. It was evident from the solvent extraction studies that SO3PhBTP formed a stronger complex with Cm3+ than with Am3+, but SO3PhBTPhen showed better complexation ability for Am3+ than for Cm3+, and SO3PhBTBP showed no selectivity for the two actinide ions. DFT calculations indicated that the coordinating 'N' atoms in BTP were more co-planar in the complex and this co-planarity was higher in the Cm3+ complex as compared to that in Am3+. In the case of BTBP and BTPhen ligands, on the other hand, the co-planarity was more pronounced in the Am3+ complexes. Mayer's bond order calculations of M-N bonds in the complexes also indicated a reversal of the complexation ability of the BTP and BTPhen ligands for Am3+ and Cm3+. Calculations of the complexation energies further supported the higher selectivity of the BTP ligand for Am3+ by -52.0 kJ mol-1, and better selectivity of the BTPhen ligand for Cm3+ by -24.7 kJ mol-1.

Selective permeation of 90Y from a mixture of 90Y/90Sr through diglycolamide impregnated supported liquid membranes.

An attempt was made in this work to evaluate a simple flat sheet supported liquid membrane technique for the separation of carrier free 90Y from 90Sr using two diglycolamide carrier ligands, (i) N,N,N',N'-tetra-n-octyl-diglycolamide (TODGA), and (ii) N,N,N',N'-tetra-(2-ethylhexyl)-diglycolamide (TEHDGA). Various experimental parameters were optimized to get selective transport of 90Y over 90Sr. At 6 M HNO3 feed acidity, >95% 90Y could be recovered selectively in just 4 h with both the ligands. Under identical experimental conditions, about 0.1% transport of Sr was also recorded which could be completely removed by passing through a Sr selective column to get medical grade 90Y pure product. A mathematical model equation was also derived and experimentally validated for predicting the transport of 90Y through membrane.

Characterization of drug resistance and genetic diversity of Plasmodium falciparum parasites from Tripura, Northeast India.

Monitoring of anti-malarial drug resistance is vital in Northeast India as this region shares its international border with Southeast Asia. Genetic diversity of Plasmodium parasites regulates transmission dynamics, disease severity and vaccine efficacy. P. falciparum chloroquine resistance transporter (Pfcrt), multidrug resistance-1 (Pfmdr-1) and kelch 13 propeller (PfK-13) genes which govern antimalarial drug resistance and three genetic diversity markers, merozoite surface protein 1 and 2 (Pfmsp-1, Pfmsp-2) and glutamate rich protein (Pfglurp) were evaluated from Tripura, Northeast India using molecular tools. In the Pfcrt gene, 87% isolates showed triple mutations at codons M74I, N75E and K76T. 12.5% isolates in Pfmdr-1 gene showed mutation at N86Y. No polymorphism in PfK-13 propeller was found. Polyclonal infections were observed in 53.85% isolates and more commonly in adults (p = 0.0494). In the Pfmsp-1 locus, the K1 allelic family was predominant (71.2%) followed by the 3D7/IC family (69.2%) in the Pfmsp-2 locus. RII region of Pfglurp exhibited nine alleles with expected heterozygosity of 0.85. The multiplicity of infection for Pfmsp-1, Pfmsp-2 and Pfglurp were 1.56, 1.31 and 1.06 respectively. Overall, the study demonstrated a high level of chloroquine resistance and extensive parasite diversity in the region, necessitating regular surveillance in this population group.

Antifolate drug resistance: Novel mutations and haplotype distribution in dhps and dhfr from Northeast India.

Malaria is a major public health concern in Northeast India with a preponderance of drug-resistant strains. Until recently the partner drug for artemisinin combination therapy (ACT) was sulphadoxine pyrimethamine (SP). Antifolate drug resistance has been associated with the mutations at dihydropteroate synthase (dhps) and dihydrofolatereductase (dhfr) genes. This study investigated antifolate drug resistance at the molecular level. A total of 249 fever cases from Arunachal Pradesh, NE India, were screened for malaria, and of these, 75 were found to be positive for Plasmodium falciparum. Samples were sequenced and analysed with the help of BioEdit and ClustalW. Three novel point mutations were found in the dhps gene with 10 haplotypes along with the already reported mutations. A single haplotype having quadruple mutation was found in the dhfr gene. The study reports higher degree of antifolate drug resistance as evidenced by the presence of multiple point mutations in dhps and dhfr genes. The findings of this study strongly discourage the use SP as a partner drug in ACT.

Flavonoids from whole Plant of Euphorbia hirta and their Evaluation against Experimentally induced Gastroesophageal Reflux Disease in Rats.

BACKGROUND: Euphorbia hirta possesses antibacterial, anti-inflammatory, galactogenic, antidiarrheal, antioxidant, hypoglycemic, antiasthmatic, antiamebic, antifungal, and antimalarial activities. OBJECTIVE: The overall objective of the current study was the investigation of the whole plant extract of E. hirta and flavonoids from E. hirta on gastroesophageal reflux disease (GERD) in rats. MATERIALS AND METHODS: The whole plant extract of E. hirta was characterized by analysis of flavonoids (HPLC: HPLC, UV, IR, MS and 1HNMR). GERD model was induced surgically in Wistar rats under pentobarbitone sodium anesthesia (50 mg/kg, i.p.) and the tissue esophagus and stomach were removed. The tissues were washed with physiological saline and were examined for GERD. The whole plant extract of E. hirta in doses of 50, 100, and 200 mg/kg were administered orally twice daily at 10:00 and 16:00 hours, respectively, for 5 days and kaempferol (100 mg/kg) or omeprazole (OMZ) in the dose of 30 mg/kg 1 hour prior to the induction of GERD. Control groups received suspension of 1% carboxymethyl cellulose in distilled water (10 mL/kg). RESULTS: The levels of gastric wall mucus increased and of plasma histamine and H+, K+ ATPase significantly decreased in groups treated by both the plant extract and flavonoids. Both the plant extract and flavonoids reduced the lipid peroxidation and superoxide dismutase and increased the levels of catalase and reduced glutathione. CONCLUSIONS: The whole plant extract of E. hirta is attributed to its antisecretory, gastroprotective, and antioxidant potential as that of quercetin, rutin, kaempferol, and proton pump blocker (omeprazole) to treat GERD. SUMMARY: The aqueous extract of whole plant of Euphorbia hirta revealed the presence of kaempferol (0.0256%), quercetin (0.0557%), and rutin (0.0151%), and the ethyl acetate fraction of whole plant of E. hirta possesses kaempferol (0.0487%), quercetin (0.0789%), and rutin (0.0184%).The levels of gastric wall mucus increased and of plasma histamine and H+-K+-ATPase significantly decreased in rats groups treated by both the whole plant extract of E. hirta and flavonoids.Both the whole plant extract of E. hirta and flavonoids reduced the lipid peroxidation and superoxide dismutase and increased the levels of catalase and reduced glutathione in rats groups. Abbreviation used: 1HNMR: Proton Nuclear Magnetic Resonance Spectroscopy, CAT: Catalase, EHAE: Aqueous extract of Euphorbia hirta, EHEF: Ethyl Acetate Fractions of Euphorbia hirta, GERD: Gastroesophageal reflux disease, GSH: Reduced Glutathione, HPLC: High performance liquid chromatography, IR: Infrared spectroscopy, LPO: Lipid Peroxidase, MDA: Malondialdehyde, MS: Mass Spectroscopy, OMZ: Omeprazole, ROS: Reactive Oxygen Species, SOD: Superoxide dismutase, TBHQ: tert-Butylhydroquinone, TLC: Thin Layer Chromatography, UV: Ultraviolet, UV: Ultraviolet-Visible Spectroscopy.

Exciton Emission Intensity Modulation of Monolayer MoS2 via Au Plasmon Coupling.

Modulation of photoluminescence of atomically thin transition metal dichalcogenide two-dimensional materials is critical for their integration in optoelectronic and photonic device applications. By coupling with different plasmonic array geometries, we have shown that the photoluminescence intensity can be enhanced and quenched in comparison with pristine monolayer MoS2. The enhanced exciton emission intensity can be further tuned by varying the angle of polarized incident excitation. Through controlled variation of the structural parameters of the plasmonic array in our experiment, we demonstrate modulation of the photoluminescence intensity from nearly fourfold quenching to approximately threefold enhancement. Our data indicates that the plasmonic resonance couples to optical fields at both, excitation and emission bands, and increases the spontaneous emission rate in a double spacing plasmonic array structure as compared with an equal spacing array structure. Furthermore our experimental results are supported by numerical as well as full electromagnetic wave simulations. This study can facilitate the incorporation of plasmon-enhanced transition metal dichalcogenide structures in photodetector, sensor and light emitter applications.

Alcohol use among school-going adolescent boys and girls in an industrial town of Assam, India.

BACKGROUND: Some people in Northeast India prepare rice-based alcoholic drinks in the household. People use these drinks in religious and social functions, and these are taken even in the presence of parents and elders. Easy access to illicit substances in industrial towns and lack of social inhibition for intake of homemade alcohol might increase the vulnerability of youth to these habits. OBJECTIVE: To estimate the prevalence of alcoholic drink user among school-going adolescent students in an industrial town of Assam. MATERIALS AND METHODS: A cross-sectional survey was designed to collect the data using a predesigned questionnaire. Personal interview was conducted to collect the data about pattern of alcohol use, type of alcoholic drinks they use, duration, and information about parents and peer. Data were analyzed using Epi-info 17 and Statistical Package for Social Sciences-17.0 (Chicago, USA, SPSS Inc.). RESULTS: About 36% out of 1285 students have tasted/used homemade alcoholic drinks (HADs) and 12.3% used commercially available alcoholic drinks (CADs). Significantly higher numbers (P < 0.001) of adolescent students (≥15 years) used CAD in comparison to children (<15 years). However, the number of younger students was higher in using HAD. Minimum age at first experience of CAD was 7 years and that of HAD was 4 years; the duration varied from 1 to 8 years and 1-15 years, respectively. Parent's behavior of taking tobacco and/or alcohol influenced the habit of their children. Father's habit was found to be associated with male offspring's habit of taking CAD. About 16% of the students used one or more substances along with alcohol. CONCLUSION: High percentage of adolescents in the industrial town of Assam use alcoholic drinks with a male preponderance. They taste alcoholic drinks at a very young age. Parent's indulgence in taking tobacco, alcohol, or both was found to influence higher intake by their offspring.

Multi-podant diglycolamides and room temperature ionic liquid impregnated resins: An excellent combination for extraction chromatography of actinides.

Extraction chromatography resins, prepared by impregnating two multi-podant diglycolamide ligands, viz. diglycolamide-functionalized calix[4]arene (C4DGA) and tripodal diglycolamide (T-DGA) dissolved in the room temperature ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide (RTIL: C4mimTf2N) on Chromosorb-W (an inert solid support), gave excellent results for the removal of trivalent actinides from acidic waste solutions. Distribution coefficient measurements on several metal ions showed selective sorption of Am(III) over hexavalent uranyl ions and other fission product elements such as strontium and cesium. The sorbed metal ions could be efficiently desorbed with a complexing solution containing guanidine carbonate and EDTA buffer. The sorption of Am(III) on both resins followed pseudo-second order rate kinetics with rate constants of 1.37×10(-6) and 6.88×10(-7)g/cpmmin for T-DGA and C4DGA resins, respectively. The metal sorption on both resins indicated the Langmuir monolayer chemisorption phenomenon with Eu(III) sorption capacities of 4.83±0.21 and 0.52±0.05mg per g of T-DGA and C4DGA resins, respectively. The results of column studies show that these resins are of interest for a possible application for the recovery of hazardous trivalent actinides from dilute aqueous solutions.

1-MCP treatment enhanced expression of genes controlling endosperm cell division and starch biosynthesis for improvement of grain filling in a dense-panicle rice cultivar.

High ethylene production in dense-panicle rice cultivars impacts grain filling. 1-MCP (ethylene action inhibitor) treatment increased assimilates partitioning, cell number and size and expression of starch synthesizing enzyme genes of developing caryopses mostly in the basal spikelets of panicle at early post-anthesis stage. The gain in cell number was less compared to the increase of size. High ethylene production in spikelets matched with greater expression of ethylene receptor and signal transducer genes. Genes encoding cell cycle regulators CDK, CYC and CKI expressed poorly on 9 DAA. 1-MCP treatment enhanced their expression; the increase of expression was higher for CDKs and lower for CKIs in basal compared to apical spikelets. Greater expression of CDKB2:1 might have lifted cytokinesis of nascent peripheral cells of endosperm, while promotion of CDKAs, CYCD2:2 and inhibition of CYCB2:2 expression contributed to endoreduplication of central cells increasing cell size and DNA ploidy level. It is concluded that the process of endoreduplication, which begins at mid-grain filling stage, is crucially linked with the final caryopsis size of rice grain. The enhanced endosperm growth brought about by repressed ethylene action during the first few days after anthesis seems to be associated with the overall increased cell cycle activity and sink strength.

Complexation thermodynamics of diglycolamide with f-elements: solvent extraction and density functional theory analysis.

Comparative extraction of trivalent lanthanide and actinide ions (La(3+), Eu(3+), Lu(3+), Am(3+) and Cm(3+)) with tetra-n-octyl diglycolamide (TODGA) was studied and showed the trend: Lu(3+) > Eu(3+) > Cm(3+) > Am(3+) > La(3+). The structure, bonding, energetic and thermodynamic parameters of the trivalent lanthanide and actinide ions (La(3+), Eu(3+), Lu(3+), Am(3+) and Cm(3+)) with a tridentate ligand, tetra-methyl diglycolamide (TMDGA), are reported in the gas and solvent phases in order to understand their complexation and extraction behaviour. The calculations were performed using the generalized gradient approximated BP86 density functional and the hybrid B3LYP functional using SVP and TZVPP basis sets. The calculated structure obtained at the BP86/SVP level of optimization was found to be in close agreement with the X-ray data and also with the structure obtained at the B3LYP/TZVP level of theory. The free energy of extraction was found to be exergonic for the explicit monomer water model. From the solvent extraction experiment the order of extraction was observed as Lu(3+) > Eu(3+) > Cm(3+) > Am(3+) > La(3+), which was in line with the trends predicted based on the free energy changes in the gas phase calculations (ΔGgp). The Born-Haber thermodynamic cycle and the COSMO (conductor like screening model) solvation model were applied to calculate the free energy of extraction, ΔGext, of lanthanide and actinide ions in the aqueous-dodecane biphasic system and ΔGext, however, predicted different extraction trends. After dispersion correction (B3LYP-D3), the free energy of extraction for the metal ions was found to follow the order: Lu(3+) > Eu(3+) > La(3+), which was also observed in the solvent extraction experiments. Both COSMO and DCOSMO-RS models predict the same metal ion selectivity trend. Different bonding analyses indicate the electrostatic and less covalent nature of interactions between the ligands and the metal ions.

Mitochondrial DNA-based genetic diversity of Anopheles nivipes in North East India.

Malaria is a major public health problem in north-east India mainly transmitted by Anopheles baimai and An. minimus while Anopheles nivipes plays an important supportive role. The genetic diversity of An. nivipes in north-east India was investigated by employing two mitochondrial DNA markers namely NADH dehydrogenase 5 (ND5) and cytochrome oxidase sub unit II (COII). High genetic diversity in An. nivipes was observed by the detection of 16 haplotypes among 30 sequences of ND5 gene and 29 haplotypes among 29 COII sequences. Anopheles nivipes of north-east India was significantly differentiated genetically with that of neighboring South-east Asian An. nivipes as revealed by pairwise FST values of 0.127 (p < 0.01) and 0.044 (p < 0.001) for ND5 and COII genes, respectively, suggesting geographical barriers to gene flow in this species between the two geographical areas resulting in significant population structuring.

Composite polymeric beads containing N,N,N',N'-tetraoctyldiglycolamide for actinide ion uptake from nitric acid feeds: Batch uptake, kinetic modelling and column studies.

Polyethersulphone (PES) based composite polymeric beads (CPB) containing TODGA (N,N,N',N'-tetraoctyldiglycolamide) as the extractant were prepared by conventional phase inversion technique and were tested for the uptake of actinide ions such as Am(3+), UO2(2+), Pu(4+), Np(4+) and fission product ions such as Eu(3+) and Sr(2+). The CPBs containing 2.5-10wt.% TODGA were characterized by various physical methods and their porosity, size, surface morphology, surface area and the degradation profile by thermogravimetry were analyzed. The batch uptake studies involved kinetics of metal ion sorption, uptake as a function of nitric acid concentration, kinetic modelling and adsorption isotherms and most of the studies involved the Am(3+) ions. The batch saturation sorption capacities for Eu(3+) loading at 3M HNO3 were determined to be 6.6±0.02, 9.1±0.02 and 22.3±0.04mgg(-1) of CRBs with 2.5wt.%, 5wt.% and 10wt.% TODGA, respectively. The sorption isotherm analysis with Langmuir, D-R and Freundlisch isotherms indicated chemisorption monolayer mechanism. Chromatographic studies indicated breakthrough of Eu(3+) (using a solution containing Eu carrier) after about 0.75 bed volume (3.5-4mL). Elution of the loaded Eu was carried out using 0.01M EDTA as the eluent.

Larvicidal activity of few select indigenous plants of North East India against disease vector mosquitoes (Diptera: Culicidae).

Mosquitoes are the vectors of several life threatening diseases like dengue, malaria, Japanese encephalitis and lymphatic filariasis, which are widely present in the north-eastern states of India. Investigations on five local plants of north-east India, selected on the basis of their use by indigenous communities as fish poison, were carried out to study their mosquito larvicidal potential against Anopheles stephensi (malaria vector), Stegomyia aegypti (dengue vector) and Culex quinquefasciatus (lymphatic filariasis vector) mosquitoes. Crude Petroleum ether extracts of the roots of three plants viz. Derris elliptica, Linostoma decandrum and Croton tiglium were found to have remarkable larvicidal activity; D. elliptica extract was the most effective and with LC50 value of 0.307 µg/ml its activity was superior to propoxur, the standard synthetic larvicide. Half-life of larvicidal activity of D. elliptica and L. decandrum extracts ranged from 2-4 days.

A remarkable enhancement in Am³âº/Eu³âº selectivity by an ionic liquid based solvent containing bis-1,2,4-triazinyl pyridine derivatives: DFT validation of experimental results.

Mutual separation of trivalent actinide (An(3+)) and lanthanide (Ln(3+)) using several soft (N) donor ligands (bis(5,6-dialkyl-1,2,4-triazinyl)pyridine (R-BTP)) is attempted for the first time in room temperature ionic liquid (RTIL) medium. The results indicate a spectacular enhancement in the selectivity as compared to that in molecular diluents with a separation factor (S.F.) of >3000 for Am(3+) over Eu(3+) using the methyl derivative (Me-BTP) in RTIL medium using [C(n)mim]·[NTf2] as the diluents (where n = 2, 3, 4, 6 or 8). Such a high S.F. value has never been reported before with any of the R-BTP derivatives in molecular diluents. An opposite trend in the distribution ratio values of both Am(3+) and Eu(3+) with the increasing size of the alkyl (R) group is observed in RTIL medium when compared with that in molecular diluents. The differences in the extraction behaviour of R-BTPs in RTILs vis-à-vis molecular diluents are explained on the basis of the difference in the nature of complexes extracted in these two distinctly different media as supported by the time resolved fluorescence (TRFS) study. An unusually high extractability and selectivity for Am(3+) over Eu(3+) with Me-BTP was attributed to the formation of a 1 : 4 complex for Am(3+), which was never reported earlier with any of the R-BTP derivatives in molecular diluents. DFT studies indicated higher metal 'd' and 'f' orbital participation (covalence) in the bonding with R-BTP in the case of Am(3+) complexes as compared to that in the case of Eu(3+) complexes, which resulted in the selectivity of these classes of ligands. The observed results may have a great significance in the radioactive waste management involving the partitioning and transmutation strategy.

Compact panicle architecture is detrimental for growth as well as sucrose synthase activity of developing rice kernels.

The increase of spikelet number in the panicles of modern super rice has made the architecture compact, as the extra spikelets are accommodated mostly on secondary branches than on primary branches. However, the grain yield did not improve because of poor grain filling, which was more visible in the basal spikelets than apical spikelets. The objective of this study was to examine the effect of the compactness and positional difference of spikelets in the panicle on grain filling by comparing the activity and genetic expression of starch synthesising enzymes in the developing kernels of lax-(Upahar and CR3856-45-11-2-7-2-5 (CR-45)) and compact-(Mahalaxmi and CR3856-29-14-2-1-1-1 (CR-29)) panicle cultivars. Upahar and Mahalaxmi are genetically related, whereas CR-45 and CR-29 are recombinant inbred lines. The grain carbohydrate concentration and activity of sucrose synthase (SUS) enzyme were estimated during the active period of grain filling. Further, expression of isoforms of SUS, ADP glucose pyrophosphorylase (APL and APS for large and small units respectively) and starch synthase (SS and GBSS for soluble and granule bound starch synthases respectively) were also assayed through PCR studies. The genotype approach used revealed grain SUS activity and starch concentration high and sugar concentration low in the lax- compared with compact-panicle cultivars and in the apical spikelets compared with basal ones. The margin of variation between apical and basal spikelets was higher in the compact- than the lax-panicle cultivars. Genetic expression of most of the isoforms of the enzymes was higher in the lax- than the compact-panicle cultivars as seen in RT-PCR studies. A quantitative appraisal of transcript levels of isoforms in the qRT-PCR identified greater expression of SUS3 in the basal spikelets of Upahar than that in Mahalaxmi and in CR-45 over CR-29, most prominently during the active period of grain filling. We conclude that proximal location as well as increased density of spikelets on panicles affected SUS3 expression in the basal spikelets. The metabolic dominance of a spikelet in rice panicle is dependent on the expression of the genes for different isoforms of starch synthesising enzymes, but the expression of SUS3 could be more specific than the others. SUS3 expression is most active during grain filling of the lax-panicle cultivars, but its dominance is reduced significantly in the kernels of the compact-panicle cultivars.