Studies on the secondary metabolites from the Indian gorgonian Subergorgia suberosa: isolation and characterization of four analogues of the cardiotoxin subergorgic acid

OBJECTIVE: The authors examined whether striatal dopamine transporters were altered in acutely (96 hours or less) abstinent cocaine-abusing subjects, as suggested by postmortem studies. METHOD: [123I] beta-CIT and single photon emission computed tomography were used to assess striatal dopamine transporter levels in 28 cocaine-abusing subjects and 24 comparison subjects matched as a group for age and gender. RESULTS: Results showed a significant (approximately 20%) elevation in striatal V3" values in acutely abstinent cocaine-abusing subjects relative to comparison subjects. An inverse correlation between dopamine transporter level and Hamilton Depression Rating Scale score was also observed. CONCLUSIONS: These findings indicate more modest elevations in striatal dopamine transporters in cocaine-abusing subjects than noted in previous postmortem reports and suggest a possible relationship between cocaine-related depression and dopamine transporter binding.     

Briarane diterpenes from the Indian Ocean gorgonian Gorgonella umbraculum

Three briarane diterpenes, junceellin (1), praelolide (2), and compound 3 (of which 3 is new), were isolated from the gorgonian Gorgonella umbraculum (EII & Sol), and their structures were established on the basis of their spectral data.     

Geochemical characteristics of REY-rich pelagic sediments from the GC02 in central Indian Ocean Basin

As a potential mineral resource, the clay minerals enriched in rare earth elements including yttrium(REY) in the deep sea have been attracting great attention. However, the enrichment mechanism of REY remains unclear. To understand the geochemical characteristics and factors controlling REY enrichment in zeolite clay in the deep sea, we conducted mineral identification by XRD, major and trace element measurements by XRF and REY analyses by ICP-MS on a 1.4-m-long sediment core(GC02) located in the Central Indian Oceanic Basin(CIOB). The main findings include:(1) the core sediments in GC02 possess elevated REY contents and exhibited a strong negative Ce anomaly, an apparent MREE bulge and positive Y anomaly. These were comparable with typical REY-rich clays in the Pacific Ocean, indicating the similar REY enrichment mechanism and the presence of REY-rich clays in the CIOB;(2) in comparison with the dataset from the Wharton Basin and DSDP site 213, the higher content of REY and stronger PAAS(Post Archean Australian Shale) normalization patterns in the GC02 sediments were likely caused by the weaker impact of terrigenous materials of GC02. The CIOB was suggested to be a promising place hosting REY rich pelagic sediments.     

The Impact of the Tropical Indian Ocean on South Asian High in Boreal Summer

The tropical Indian Ocean (TIO) is warmer than normal during the summer when or after the El Nino decays. The present study investigates the impact of TIO SST on the South Asian High (SAH) in summer. When the TIO is warmer, the SAH strengthens and its center shifts southward. It is found that the variations in the SAH cannot be accounted for by the precipitation anomaly. A possible mechanism is proposed to explain the connection between the TIO and SAH: warmer SST in the TIO changes the equivalent potential temperature (EPT) in the atmospheric boundary layer (ABL), alters the temperature profile of the moist atmosphere, warms the troposphere, which produces significant positive height anomaly over South Asia and modifies the SAH. An atmospheric general circulation model, ECHAM5, which has a reasonable prediction skill in the TIO and South Asia, was selected to test the effects of TIO SST on the SAH. The experiment with idealized heating over the TIO reproduced the response of the SAH to TIO warming. The results suggest that the TIO-induced EPT change in the ABL can account for the variations in the SAH.     

Frequency and impact of autosomal dominant polycystic kidney disease in the Seychelles (Indian Ocean)

BACKGROUND: As little such data is available in African populations, we investigated the prevalence of ADPKD and the impact of the disease in the Seychelles islands, where approximately 65% of the population is of African descent and 30% of Caucasian or mixed descent. METHODS: Prevalent cases were identified over a 3-year period by requesting all the doctors in the country (most of them are employed within a national health system) to refer all presumed or confirmed cases and by systematically examining the family members of all confirmed cases. The diagnosis was based on standard criteria including ultrasonographic findings and family history. RESULTS: Forty-two cases were identified in this population of 74,331 inhabitants, a total prevalence (per 100,000 total population) of 57 (95% CI, 41-76). All but one of the cases were of Caucasian descent so that the prevalence rates of the disease in the populations of Black and Caucasian descents were respectively 2 (0-11) and 184 (132-249). The prevalence rates of the gene(s) carriers were estimated to be 75 (45-117) in the total population respectively 6 (0-33) and 236 (140-372) in the Black and Caucasian populations. Haplotype analysis in 58 cases from three families showed a common DNA fragment in all affected individuals. Cases had significantly higher blood pressure compared to the general population and 21% had serum creatinine higher than 120 mumol/l. Among the established pedigrees, mean age of death between 1960 and 1995 (haemodialysis was introduced in 1992) was younger in subjects with than those without ADPKD (50.5 vs 67.7 years; P < 0.001). CONCLUSIONS: In the Seychelles, ADPKD clusters in the Caucasian population (possibly a founder effect), is rare in individuals of black descent, and is associated with substantial clinical and survival impact.     

Extraction of Zinc‐Cobalt from Sulphate Solution of Cobalt Cake by D2EHPA in the Processing of Indian Ocean Nodules

During the processing of Indian ocean nodules, cobalt cake containing zinc in equal proportion is produced. In order to get pure cobalt and zinc from the sulphate leach solution of cake, a solvent extraction process has been considered using an organic extractant, di‐(2‐ethylhexyl) phosphoric acid (D2EHPA). Separation of cobalt and zinc has been carried out by mixing aqueous and organic phases in a rectangular vessel and separating the phases after equilibration in a glass funnel. The analysis of the metal from the aqueous phase was made by atomic absorption spectrometer to compute the metal transfer. The extraction and separation studies carried out under the different operating conditions indicated favourable zinc extraction at the lower pH (~ 2) with partially saponified D2EHPA. The small amount of cobalt co‐extracted with zinc was scrubbed with dilute sulphuric acid. With completely saponified D2EHPA, a high degree of cobalt extraction (99.8%) was achieved at aqueous feed pH of 5.0. The flow sheet developed could be used for the selective extraction and separation of zinc and cobalt from the leach liquor of cobalt cake.     

Electrochemical Phenomena in MnO2-Fes2 Leaching in Dilute HCl. Part 3: Manganese Dissolution from Indian Ocean Nodules

Abstract

The present paper deals with the kinetics and mechanism of MnO₂ dissolution from sea bed manganese nodules in the presence of pyrite. Manganese (iv) was found to dissolve mostly through reduction by ferrous ions generated by the oxidation of pyrite by ferric ions which was considered to take place through two reactions, one producing S° and the other [SO₄^2?]. These two reactions were found to take place at a mole proportion of about 20% and 80%, respectively, but in terms of electron involvement the participation of the former is insignificant. The dissolution rates obtained from leaching studies were analysed based on the kinetic expressions derived previously and were found to confirm the theoretical basis. The kinetics and mechanism vary depending on whether or not sufficient acid is present. In the presence of sufficient acid the expression {[Fe³⁺]/(Rate)² = K ₃[Fe²⁺] + K ₄} is valid and in depleted acid conditions {rate = K ₆[H⁺][Fe²⁺])^1/2} holds good.

Résumé

Le présent document traite de la cinétique et du mécanisme de dissolution, en présence de pyrite, du MnO₂ de nodules de manganèse du fond de la mer. On a trouve que le manganèse (iv) se dissolvait en grande partie par réduction par des ions ferreux générés par l'oxydation de la pyrite par des ions ferriques. On considère que ceci se produit par l'intermédiaire de deux réactions. l'une produisant S° et l'autre, [SO₄^2?]. Ces deux réctions se produisent à des proportions, en mol, d'environ 20% et 80%, respectivement, mais en ce qui a trait à l'impliçation d'électron, la participation de la première est insignifiante. On a analysé les taux de dissolution obtenus des études de lessivage en se basant sur les expresions cinétiques dérivées auparavant, confirmant la base théorique. La cine[Faac]tique et Ie mécanisme varient dépendant qu'il y a ou non suffisamment d'acide présent. En présence de suffisamment d'acide, l'expression {[Fe³⁺]/(taux)² = K ₃[Fe²⁺] + K₄} est valide et, en conditions appauvries en acide, {taux = K ₆[H⁺][Fe²⁺]^1/2} tient.     

Development of hydroxyapatite derived from Indian coral

A simple method of converting the calcium carbonate skeleton of the corals available in the Indian coast into hydroxyapatite granules has been developed. By heating the coral to 900 degrees C, the organic materials were eliminated. Powder X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) were employed to characterize the coral and to optimize the processing parameters as well as to confirm the hydroxyapatite formation. The coral used exhibits the presence of both aragonite and calcite phases (dimorphism). At a temperature of 900 degrees C the coral was found to decompose all the carbonate phases. The pre-heated coral is converted into hydroxyapatite by a chemical exchange reaction with di-ammonium phosphate under hydrothermal conditions. The hydroxyapatite obtained was in powder form and does not contain any impurities. The in vitro solubility test of the apatite granules performed in Gomoris, Michalelis, Sorensens, Ringer's and phosphate buffer of pH 7.2 and de-ionized water indicated the stability of the coralline hydroxyapatite.     

Existing and New Processes for Beneficiation of Indian Iron ores

The iron ore industries of India are expected to bring new technologies to cater to the need of the tremendous increase in demand for quality ores for steel making. With the high-grade ores depleting very fast, the focus is on the beneficiation of low-grade resources. However, most of these ores do not respond well to the conventional beneficiation techniques used to achieve a suitable concentrate for steel and other metallurgical industries. The present communication discusses the beneficiation practices in the Indian context and the recent developments in alternative processing technologies such as reduction roasting, microwave-assisted heating, magnetic carrier technology and bio-beneficiation. Besides, the use of new collectors in iron ore flotation is also highlighted.     

The Oscillation between Tropical Indian Ocean and North Pacific:Evidence and Possible Impact on Winter Climate in China

This paper provides evidence that the variation of boreal winter sea level pressure (SLP) over the North Pacific is out-of-phase with SLP fluctuation over the tropical Indian Ocean on both the interdecadal and interannual time scales. Subsequently, a SLP between tropical Indian Ocean and North Pacific (TIO-NP) oscillation index is defined to indicate the variation of such out-of-phase fluctuation. Moreover, the simultaneous surface air temperature and precipitation anomalies in China are closely related to TIO-NP oscillations. Below-normal surface air temperature anomalies in the northern and the eastern part of China, and less rainfall in southern China,correspond to positive TIO-NP oscillation phase with negative SLP anomalies in tropical Indian Ocean and positive anomalies in North Pacific. The TIO-NP oscillation affects China's winter climate anomalies,possibly through modulating the northeast East Asia winter monsoon.     

Changing pattern of respiratory tuberculosis in the UK in adult patients from the Indian subcontinent

BACKGROUND: Clinical observations over a 12 year period have suggested a changing pattern of adult respiratory tuberculosis in patients from the Indian subcontinent in two districts of the United Kingdom with a high incidence of tuberculosis. METHODS: Details of all patients for the period 1981-92 residing in the Newham and Blackburn districts aged 15 and over whose ethnic origin was from the Indian subcontinent (n = 1308) were analysed by stepwise logistic regression to determine the relationship between sputum smear positivity, sputum culture positivity, and isolated mediastinal lymphadenopathy, year of notification, age, sex, ethnic group (Indian or Pakistani), and whether the patient had visited the Indian subcontinent within the last three years. RESULTS: The proportion of cases who were smear positive rose over the 12 years of the study, as did the proportion of culture positive cases. The proportion with isolated mediastinal lymphadenopathy fell. These changes took place in both districts. They were not explained by demographic changes in age, sex, or ethnic group, nor was there evidence that smear and culture positivity increased in those who had recently visited India or Pakistan. CONCLUSIONS: The pattern of tuberculosis in adult patients originating from the Indian subcontinent has altered over time towards that seen in the white population in the UK.     

The complete genomic sequence of an HTLV-II isolate from a Guahibo Indian from Venezuela

A polyclonal CD3(+), CD8(+) T-cell line, G2, was derived from the peripheral blood of a seropositive, PCR-positive, HTLV-IIB infected Guahibo Indian from Venezuela. The cell line is productively infected with HTLV-IIB. The entire HTLV-II G2 proviral DNA was sequenced via PCR using overlapping HTLV-II primer pairs. Phylogenetic analyses indicate that HTLV-II G2 is the most divergent HTLV-IIB strain identified to date. Characterization of its deduced proteins and its relationship to other members of the PTLV/BLV genus of retroviruses are discussed.     

Ceratomyxa drepanopsettae in the gallbladder of Atlantic halibut, Hippoglossus hippoglossus, from the northwest Atlantic Ocean

Trophozoites of Ceratomyxa drepanopsettae Averintsev, 1907 (Myxosporea: Ceratomyxidae) containing prominent refractile granules were found in the gallbladders of all but one of eight halibut, the exception being a single juvenile. They ranged in shape and size from globular forms 5-10 micron in diameter, to rounded structures with pseudopodia and one or more processes that were up to 500 micron in length and packed with refractile granules. Some trophozoites were free in the bile, while others were attached to the epithelium of the gallbladder wall by pseudopodia which extended between the microvilli. Many free trophozoites were attached to each other by septate junctions between their pseudopodia. There were small cylindrical papillae on the surface of the trophozoites, and the rounded portions contained two vegetative nuclei, generative cells (some attached by junctions) and, in many cases, feeding vacuoles. During sporogony, a binucleate sporoplasmic cell and the capsulogenic cells of some sporoblasts were engulfed by valvogenic cells before they began to differentiate; whereas other sporoblasts consisted of six cells attached to each other, two being capsulogenic cells containing external tubes, two sporoplasmic cells and two valvogenic cells. There was a septate junction around the opening of the rounded polar capsule of the spore, between the capsulogenic and valvogenic cell. Sporoplasmosomes appeared to form in smooth membraned vesicles, possibly part of the Golgi apparatus. Spores had thin, delicate membrane, and elongate shell-valves, most of which were asymmetric, and bent or folded. A sporoplasm extended on either side of the distinct, straight suture line, but did not penetrate into the valves.     

Simulations of Dye Releases off the Coast of New Jersey: Development and Validation of an Ocean Outfall Mixing Model

A kinematic mixing model has been developed to predict far field effluent distributions for ocean discharges. The model allows for complex outfall configurations and time varying discharge rates to be simulated. The model can use field observations or the output from a proven near field mixing model as input to this far field mixing model. The model uses observed or simulated horizontal currents at one location to advect the effluent plume and a scale-dependent “diffusion velocity” submodel to account for horizontal diffusive processes. To collect data to calibrate and verify the model, long-term continuous dye release experiments were conducted at two New Jersey ocean outfalls. Based upon the results of the dye release experiments, appropriate values for the diffusion velocity were determined for each outfall. Simulations using these diffusion velocities provided reasonable predictions of plume width and of average dye concentration at each transect for each outfall. This work demonstrates that an Eulerian velocity observed at one location in the coastal ocean off New Jersey may be used to predict Lagrangian transport over a distance of several kilometers.     

用LIX84从富钴结壳硫酸浸出液中选择性萃取铜

采用LIX84作萃取剂、硫酸作反萃剂 ,从大洋富钴结壳常温常压活化硫酸浸出除铁后液中萃取铜。试验考察了相比、平衡水相pH值、时间等因素对LIX84萃铜的影响。结果表明 ,相比、平衡水相 pH值、混合时间都对铜的萃取率有一定影响。最后优化出的萃取工艺条件为 (体积百分数 )有机相 12 %LIX84+ 88%煤油 ,室温 ,相比 (O/A)=1/ 2 0 ,出口水相pH2 60± 0 0 5 ,萃取级数为 2级 ,每级混合时间 5min。经过 2级萃取、1级洗涤、3级反萃后 ,可以得到完全符合电解沉积要求的硫酸铜溶液 ,从而使浸出液中的铜与其它金属彻底分离