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.

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.

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.

An insight into third-phase formation during the extraction of thorium nitrate: evidence for aggregate formation from small-angle neutron scattering and validation by computational studies.

Small-angle neutron scattering (SANS) studies were carried out to compare the aggregation behavior of 1.1 M solutions of tributyl phosphate (TBP) and N,N-dihexyl octanamide (DHOA) dissolved in different deuterated diluents, viz., n-dodecane, chloroform, and benzene, during the extraction of Th(IV) from nitric acid medium. The scattering data was treated using the Baxter sticky spheres model. The third phase formed in the case of DHOA displayed higher aggregation tendency compared to that of TBP. These studies have demonstrated that the nature of the diluents plays an important role in the aggregation behavior of the extracted species (reverse micelles). No third phase was observed in the case of chlorinated and aromatic diluents like chloroform and benzene during the extraction of Th(IV) from nitric acid medium. Theoretical calculations were also performed to gain insights into the binding of thorium nitrate with TBP and DHOA models. These calculations suggest that two to three molecules of both DHOA and TBP strongly coordinate to Th(NO3)4. It is noted that the highly charged Th(IV) cations are screened by nitrates and extractants which enables the interaction of second unit of such complex through noncovalent interactions.

Polymeric beads containing Cyanex 923 for actinide uptake from nitric acid medium: Studies with uranium and plutonium.

Conventional phase inversion technique has been successfully applied for the preparation of the solid phase extractant (SPE), Cyanex 923 loaded polymer beads. Two types of polymer beads prepared by blending Polyetherether ketone with card (PEEKWC)/DMF with 5% Cyanex 923 (SPE-I, av bead size: 900µm) and 10% Cyanex 923(SPE-II, av. bead size: 1100µm) were evaluated for the uptake of actinide ions. The polymer beads were characterized by various physical methods such as thermal analysis, surface morphology analysis by SEM, EDAX techniques, etc. The polymer beads were used for the experiments involving the uptake of both U(VI) and Pu(IV) at tracer scale and U(VI) at milli molar concentrations from nitric acid feeds. The actinide ion uptake studies involved kinetics of metal ion sorption, adsorption isotherms, and column studies. The metal sorption capacities for U(VI) at 3M HNO3 were found to be 38.8±1.9mg and 54.5±1.7mg per g of SPE-I and SPE-II, respectively. The sorption isotherm analysis with Langmuir, D-R and Freundlisch isotherms indicated chemisorption monolayer mechanism. Column studies were also carried out using 4.5mL bed volume columns containing about 0.4 and 0.45g of SPE-I and SPE-II, respectively. The breakthrough profiles were obtained for U(VI) and the elution profiles were obtained using 1M Na2CO3 as the eluent.

Characterization of the species formed during the extraction of thorium employing tri-n-butyl phosphate and N,N-dihexyl octanamide as extractants by laser desorption/ionization time-of-flight mass spectrometry.

Laser desorption/ionization-time-of-flight mass spectrometry (LDI-ToF-MS) has been applied to identify and characterize the organic phase species formed during the extraction of thorium nitrate by 1.1 M tri-n-butyl phosphate (TBP) and N,N-dihexyl octanamide (DHOA) solutions in n-dodecane. The aqueous phase thorium concentrations (at 4M HNO3) have been suitably chosen to get Loaded organic phases with/without third-phase. The extracted species have been characterized for the first time using LDI-ToF-MS. The results show feasibility of the use of this technique for understanding the extraction mechanisms and third-phase formation behavior of different extractants. The different chemical species observed using this technique are consistent with those observed by small-angle neutron scattering (SANS).

A rapid online estimation method for radiostrontium in soil samples using crown ether and supercritical fluid extraction.

Crown ethers dissolved in suitable medium are well known to promote the extraction of alkali (M(+)) and alkaline-earth (M(2+)) cations from aqueous to organic phases. Di-tert-butyl-cyclohexano18crown6 (DTBDCH18C6) has been identified as an effective and selective extractant for Sr(II) from nitric acid medium. An attempt was made to evaluate the feasibility of (85,89)Sr recovery from synthetic soil samples (0.5 g; particle size: <100 µm) by SFE route (pressure: 200 kg/cm(2); T: 40 °C) employing DTBDCH18C6 dissolved in methanol/nitric acid medium as phase modifier. The effect of various experimental parameters such as (i) dynamic/static mode of extraction, (ii) time of equilibration (15-150 min during static mode of extraction using 3 mL of modifier), (iii) nitric acid concentration (1-6M), (iv) picrate as counter-anion, and (v) crown ether concentration in the modifier phase (2×10(-4)-2×10(-3) M) on Sr(II) extraction was studied. Based on these studies, 2×10(-4) M DTBDCH18C6 dissolved in methanol/4M HNO(3) was chosen as modifier and 30 min as equilibration time for batch mode employing 3 mL modifier solution in the static mode. Three successive batches employing 3 mL modifier solution (after each extraction stage) showed near quantitative recovery (>95%) of (85,89)Sr from soil samples. Dynamic mode extraction using 2×10(-4) M DTBDCH18C6 dissolved in methanol/4M HNO(3) as modifier suggested that near quantitative recovery (>95%) of (85,89)Sr could be achieved within 1h. By contrast, ~10% (137)Cs extraction was observed from soil samples under identical experimental conditions. These studies demonstrate the potential of the SFE technique for the analysis of (90)Sr in different environmental samples.

Determinants for the retreatment groups of pulmonary tuberculosis patients treated in a DOTS programme in Sikkim, India.

OBJECTIVE: To assess knowledge, attitude and different health-seeking behaviours among 250 cured and 250 category-II tuberculosis patients. METHODS: A case-control study was conducted in different health settings in Sikkim, a part of the Indian continent. A questionnaire was filled for the purpose. RESULTS: Results showed significant differences in overcrowding, smoking and alcohol intake. There was a general unawareness with the disease and its treatment between the two groups. 45% of the respondents reported that tuberculosis is caused by germs. 81.4% stated that tuberculosis presents only as cough. 94.8% of the case group and 90.8% of the control group stated that it is a transmissible disease. Sharing food with tuberculosis patients (64% of case group, 55% of the control group; p < 0.05), inadequate diet (16.4% of case group, 9.6% of the control group; p < 0.03) were mentioned as modes of transmission. Sixty six per cent of the case group and 56.8% of the control group mentioned the use of DOTS for prevention and control (p < 0.05). Sixty three per cent of the control group regarded tuberculosis as a life threatening condition (p < 0.00) [(adjusted OR = 2.04, (95% CI: 1.43, 2.93)]. Tuberculosis was considered as a completely curable disease by 96.4% of the case group (p < 0.05). 40.6% of the respondents agreed to be in contact with a tuberculosis infected person. 64% of the retreatment group discontinued their treatment due to frequent travelling for work. CONCLUSION: The study revealed lack of knowledge, positive attitude and inappropriate health seeking behaviours among of the tuberculosis patients, irrespective of their categorization.

Selective separation of radio-cesium from acidic solutions using supported liquid membrane containing chlorinated cobalt dicarbollide (CCD) in phenyltrifluoromethyl sulphone (PTMS).

A supported liquid membrane method was developed using chlorinated cobalt dicarbollide (CCD) in phenyltrifluoromethyl sulphone (PTMS) as the carrier, impregnated in PTFE flat sheet membranes for the selective separation of Cs(I) from nitric acid feed solution. Solvent extraction studies were carried out for optimizing the feed as well as strip conditions. >95% Facilitated transport of Cs(I) was observed in about 3h when 1M HNO(3) and 8M HNO(3) were used as the feed and strip solutions, respectively while 0.025M CCD in PTMS was used as the carrier extractant. Selectivity studies, carried out using a mixture of radiotracers viz. (51)Cr, (59)Fe, (99)Mo, (99m)Tc, (106)Ru, (137)Cs, (152)Eu and (241)Am, indicated selective transport of Cs(I) with DF values >100. Though reproducibility of the transport data was excellent when carried out in two successive transport experiments with freshly loaded carrier solvent, the stability of the membrane was poor which restricts its long term use.

A novel malonamide grafted polystyrene-divinyl benzene resin for extraction, pre-concentration and separation of actinides.

A new chelating polymeric extraction chromatographic resin was prepared by chemical anchoring of N,N'-dimethyl-N,N'-dibutyl malonamide (DMDBMA) with chloromethylated Merrifield resin((R)). The grafted resin exhibited stronger binding for hexavalent and tetravalent actinides such as U(VI), Th(IV) and Pu(IV) over trivalent actinides, viz. Am(III) and Pu(III). Batch studies on solid phase extraction performed over a wide range of acid solution (0.01-6M HNO(3)) revealed that ternary mixer of uranium, americium and plutonium or thorium, americium and plutonium could be separated from each other at 1M HNO(3). Desorption of U(VI), Pu(IV) and Am(III) from the loaded resin was efficiently carried out using 0.1M alpha-HIBA, 0.25M oxalic acid and 0.01M EDTA, respectively. Quantitative pre-concentration of actinide ions such as Th(IV) and U(VI) was possible from 3M HNO(3) solution. The practical utility of the grafted resin was evaluated by uranium sorption measurements in several successive cycles. The sorption efficiency of the resin with respect to uranyl ion remained unchanged even after 30 days of continuous use. The surface morphology of the resin was monitored with the help of scanning electron microscopy (SEM) technique.

Evaluation of calix-crown ionophores for selective separation of radio-cesium from acidic nuclear waste solution.

Extraction of Cs-137 from nitric acid was carried out using nitrobenzene solutions of calix-crowns such as calix[4]arene-bis(crown-6) (CC-A), calix[4]arene-bis(benzo crown-6) (CC-B) and calix[4]arene-bis(napthocrown-6) (CC-C). CC-C was found to be superior extractant for Cs(I) as compared to the other two calix-crown ligands used in the present study. The effect of diluent on the extraction of Cs(I) indicated the trend: nitrobenzene>dichloroethane>chloroform>decanol>>carbon tetrachloride approximately n-hexane approximately toluene. Subsequently, the studies were carried out with nitrobenzene solutions of the calix-crown ligands (mainly CC-C) on the effects of (a) aqueous phase acidity, (b) ligand concentration, and (c) cesium concentration on Cs extraction from nitric acid media. Conditions for quantitative extraction and stripping were optimized and the extracted species conformed to {[CsL]+.[NO3]-.nH2O}. Selectivity studies were carried out using an irradiated natural U target involving tracer amount of fission products activities. Extraction of Cs(I) from a synthetic high level waste solution was also carried out. The promising results obtained in the present studies indicate possible use of the calix-crown ligand for Cs(I) recovery from the acidic high level waste.

Malaria control in a forest camp in an oil exploration area of Upper Assam.

BACKGROUND: Assam, in north-east India, is extremely rich in hydrocarbon deposits and the oil industry is the major contributor to its economy. A large number of oil fields and related installations in Assam are located in forest areas or on their fringes where malaria is a serious problem among field staff and security personnel, adversely affecting oil production. We carried out an operational research study for one year in a forest-based industrial security camp of Dibrugarh district and developed an effective malaria control strategy for such areas. METHODS: The specific strategy was formulated and implemented after taking into account the local epidemiology of malaria, vector's ecology and malaria risk behaviour of the camp inmates. The strategy was based on reducing the man-vector contact, using deltamethrin-treated mosquito nets in conjunction with mosquito repellent cream and weekly chemoprophylaxis with 300 mg chloroquine. The impact of the strategy was monitored entomologically and epidemiologically for one year after implementation. RESULTS: The mean landing rate of Anopheles dirus, the vector mosquito in the camp area, was 5.03 per person per night during the monitoring. In spite of such a high density of the vector, the man-vector contact was effectively checked by the intervention measures adopted. As a result, the incidence of malaria in the camp was reduced by > 90% as compared to previous years and the number of malaria cases came down from 6.7 per 1000 man-nights in 1998-99 to 0.06 in 2000-01. Mortality due to malaria was completely eliminated. CONCLUSION: Control of malaria should be based on the local determinants of transmission. The use of insecticide-treated mosquito nets in conjunction with a mosquito repellent cream is a good intervention for controlling Anopheles dirus-transmitted malaria in the forests of north-east India. The control module developed on the principle of reducing man-mosquito contact is easy to implement, cost-effective and replicable in similar forest-based locations.

Ameloblastic fibroma in the midline of mandible: a case report.

The ameloblastic fibroma (AF) is a rare benign mixed odontogenic tumor. It is composed of both epithelial and mesenchymal elements, but lacks of any calcified dental structures. Most of these tumors occur in the mandible and appears preferentially in the posterior portion of the dental arch with molar area predominates over premolar area. It is important to differentiate the lesion from ameloblastoma, since unlike the latter, it does not exhibit a locally invasive growth pattern. It is a well-circumscribed lesion and does not require the radical excision that may be necessary to effect cure with ameloblastoma. The present case report describes a 15-year-old patient with an ameloblastic fibroma in the symphysis of the mandible, a rare reported site. In the beginning of the article an extensive review of the previously published literature on ameloblastic fibroma has been made. In the later part, the diagnosis, differential diagnosis, histology and therapeutic procedures and postoperative follow up of the present case have been described.

Biotoxicity of mercury to Chlorella vulgaris as influenced by amino acids.

The toxicity of mercury ion, on Chlorella vulgaris, is largely influenced by amino acids. Five amino acids, namely alanine, asparagine, glutamic acid, cysteine and histidine, were added separately to the medium containing static dose of mercury. Survival (%) of the alga was reduced with the increasing concentrations of mercury. Of these five amino acids, cysteine was found to be the most effective while alanine and glutamic acid were the least effective on reducing the toxic effect of mercury on the alga measured in terms of growth, chlorophyll and protein content. The order of detoxification was Alanine < Glutamate < Asparargine < Histidine < Cysteine. Amino acids from ligands with Hg2+ making it less toxic to the alga and produce an additional source of energy for growth and development.

Extraction of ternary complexes of thorium(IV) with 3-phenyl-4-benzoyl-5-isoxazolone and neutral donors from nitric acid medium.

The extraction behaviour of thorium(IV) from aqueous nitric acid employing 3-phenyl-4-benzoyl-5-isoxazolone (HPBI) in the presence of tri-n-octyl phosphine oxide (TOPO) as well as tri-n-butyl phosphate (TBP) in xylene medium was investigated. The extraction constant (log k(ex)) for the binary organic phase species Th(PBI)(4) was determined to be 8.26 which is by far the largest amongst the corresponding values known for other beta-diketones. The overall extraction constant (log K) for the ternary species Th(PBI)(4) TBP and Th(PBI)(4).2TOPO were estimated to be 14.96 and 20.96 respectively. An inverse correlation of the adduct formation constant (log K(s)) with the pK(a) of the beta-diketones, 2-thenoyltrifluoroacetone, 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone and HPBI, was observed. The steric as well as the electronic effects of adduct formation have been discussed. Analytical application of HPBI for the separation of (234)Th radiotracer from natural uranium (99.3% (238)U) has been suggested.

Role of messenger system in orthodontic tooth movement.

Various in vivo and in vitro studies have established that arachidonic acid metabolites i.e., prostaglandins and leukotriens play a key role in the conversion of orthodontic pressure stimuli into a cell mediated response. However, considering the different response of osteoblasts and osteoclasts to the same chemical stimuli that leads to the deposition of bone on tension side and resorption on pressure side it has been suggested that it is the messenger system that modulates the behaviour of cells. The messenger system translates a wide array of external stimuli (first messenger) in to a narrow range of internal signals (second messengers). The role of Cyclic-AMP (C-AMP), Inositol phosphate (IP3), and Diacyleglycerol (DAG) as second messengers in the mediation of orthodontic tooth movement have been discussed in this article.