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Gold mill tailings (GMT) are waste from gold mill processing plants usually collected and stored in tailings storage facilities (TSF) and left for years in many abandoned mines in the world. GMT is in large amounts and contains high concentrations of chemicals and compounds that may harm human lives and the ecosystem if not well-maintained. A characterization study is conducted on GMT from a small-scale mill processing plant in Agusan del Sur, Philippines, and its potential utilization as an additive to sand and cement in making cement-stabilized products is also evaluated. The elemental and oxide composition, the presence of free and total cyanide, and particle size analysis were determined. Different proportions of gold mill tailings, cement, and sand were prepared and tested for compressive strength and water absorption. The results showed that the GMT contained some potentially valuable elements like tin, zinc, and europium. GMT also contains potentially hazardous elements like lead (663ppm), arsenic (157ppm), and mercury (17ppm). The free cyanide in the effluent is also found at 1.9 ppm. These elements and compounds are potentially hazardous in case of tailings seepage or overflow to groundwater and neighboring agricultural lands. The evaluation of cement-stabilized samples shows that the GMT from the study area can be utilized as an additive to cement and sand in the production of cement-stabilized products however it must be properly treated and handled to ensure the safety of workers. The TCLP result showed that the product is non-toxic and non-reactive. The construction and proper maintenance of a TSF for small-scale gold milling plants in the study area is recommended to prevent environmental, health, and safety risks.

Determinar el resultado obtenido tras tratamiento con 131I en pacientes con bocio multinodular (BMN) y nódulo autónomo tóxico (NAT) en función de la dosis administrada (555 o 740MBq) y de otros factores relacionados con el paciente, la enfermedad o tratamientos previos.

La Guajira upwelling system has shown a moderate cooling (∼−0.05°C dec−1) over the period 1982–2014 for the months with strong upwelling (JFM). This contrasts with the general warming observed for most of the Caribbean region (∼0.25°C dec−1) over the same period. Cooling is in good agreement with the upwelling increase (∼0.04 m2s−1dec−1) observed in the region during winter months, although the position of the peaks in upwelling and SST trends does not coincide exactly due to the presence of the Caribbean Coastal Undercurrent. All Caribbean region (0.25°C dec−1), while in the La Guajira upwelling system (−0.05°C dec−1)This cooling is in good agreement with the upwelling increase 0.04 m2s−1dec−1during winter monthsThe trends shown here had not been documented in previous research

A simultaneous study of acid−base and solubility equilibria of acetylsalicylic acid has been carried out by potentiometry with a glass electrode in NaCl and KNO3 at several ionic strengths and 25 °C. The dependence of the stoichiometric equilibrium constant on ionic strength has been analyzed according to different specific interaction theories. The experimental data also allow one to estimate both the salting coefficient of acetylsalicylic acid in the studied electrolytes and the specific interaction parameters of acetylsalicylate ion with cations of the support electrolyte.

Four new metabolites with carotane skeletons, trichocaranes A (1), B (2), C (3), and D (4), were isolated from Trichoderma virens and their structures established by the interpretation of NMR and mass spectroscopic data. The trichocaranes significantly inhibited the growth of etiolated wheat coleoptiles:  40% at 10^-4 M with 1 and 2 and 86% at 10^-3 M with 3.

From an aqueous extract of Helianthus annuus L. cvs. SH-222 and VYP leaves, six new heliannuols have been isolated:  three 7,10-heliannanes, heliannuols F (1), I (4), and J (5) and three 7,11-heliannanes, heliannuols G (2), H (3), and K (6). Their structure elucidation was based on extensive spectral studies. The phytotoxicity exhibited by compounds 1−4 and 6 suggests that these new bioactive sesquiterpenes may be involved in plant defense against dicotyledons.

The density and viscosity of aqueous solutions of sodium dithionite, sodium hydroxide, sodium dithionite + sucrose, and sodium dithionite + sodium hydroxide + sucrose were measured at temperatures from (25 to 40) °C. The concentration ranges were (0 to 1.0) mol·dm^-3 for sodium dithionite, (0 to 1.0) mol·dm^-3 for sodium hydroxide, and (0 to 171) g·dm^-3 for sucrose. The experimental values were correlated with the concentration of sucrose. The maximum deviation was always less than 0.2%.

Steroids have been widely used to prevent the severe secondary strictures that inevitably follow accidental ingestion of caustic substances by children, though with controversial results. To confirm the efficacy of large early doses of dexamethasone, we conducted an experimental study in rabbits. A cotton swab soaked in sodium hydroxide was placed on the esophageal mucosa of 30 rabbits. The rabbits were then treated with antibiotics and randomly allocated to one of three groups. One group received no steroids; the second group was treated with prednisolone; and the third was given dexamethasone. After 21 days, the rabbits were killed and the severity of the lesion was evaluated by radiological, anatomical, and histological examination. Rabbits with moderate or severe stricture, as defined on the basis of radiological examination, made up 80% of the control group, 70% of the prednisolone-treated group, and 40% of the dexamethasone-treated group. Rabbits with third-degree burns, with or without macroscopic ulcers, made up 60% of the control group, 40% of the prednisolone-treated group, and 30% of the dexamethasone-treated group. On histological examination, rabbits with third-degree lesions made up 70% of the control group, 40% of the prednisolone-treated group, and only 20% of the dexamethasone-treated group. Only the difference between the control and dexamethasone-treated group was statistically significant. Taken together, our results clearly indicate that, in rabbits, rapid postburn administration of dexamethasone leads to significant reductions in the frequency and severity of strictures and in the severity of burns.

There are a number of discrepancies in the literature regarding the protein composition of the avian reoviruses. The present study demonstrates that avian reovirus S1133 contains at least 10 proteins (lambdaA, lambdaB, lambdaC, muA, muB, muBC, muBN, sigmaA, sigmaB, and sigmaC). Polypeptides muB, muBC, muBN, sigmaB, and sigmaC are components of the outer capsid layer of the virus, while lambdaA, lambdaB, muA, and sigmaA are core polypeptides. Protein lambdaC is a component of both layers, extending from the inner core to the outer capsid. The minor outer-capsid polypeptide sigmaC is shown to be the cell attachment protein, since it is the only viral polypeptide present in extracts of S1133-infected cells that binds specifically to chicken embryo fibroblasts; furthermore, its binding to avian cells was competitively inhibited by S1133 reovirions but not by mammalian reovirions. Our results also show that sigmaC is an oligomeric protein both in the virion and free in the cytoplasm, and preliminary results suggest that the multimer is made up of three monomeric units.

Avian reovirus S1133 specifies at least 10 primary translation products, eight of which are present in the viral particle and two of which are nonstructural proteins. In the work presented here, we studied the covalent modifications undergone by these translation products in the infected cell. The structural polypeptide mu2 was shown to be intracellularly modified by both myristoylation and proteolysis. The site-specific cleavage of mu2 yielded a large carboxy-terminal fragment and a myristoylated approximately 5,500-Mr peptide corresponding to the amino terminus. Both mu2 and its cleavage products were found to be structural components of the reovirion. Most avian reovirus proteins were found to be glycosylated and to have a blocking group at the amino terminus. In contrast to the mammalian reovirus system, none of the avian reovirus polypeptides was found to incorporate phosphorus during infection. Our results add to current understanding of the similarities and differences between avian and mammalian reoviruses.

Avian reovirus S1133 encodes 10 primary translation products, 8 of which are structural components of the viral particle and 2 of which are nonstructural proteins. The identity of the gene that codes for each of these polypeptides was determined by in vitro translation of denatured individual genome segments.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.