[en] A method for the simulation determination of inorganic As(III) and As(V) is described, which involves arsine generation, measurement of the molecular absorption of arsine in the gas phase at 190 nm and quantification od As(III) and As(V) based on different heights and areas of absorbance versus time profiles of arsine generated from both inorganic species. The limits of detection were 0.5 μg of As(III) and 3 μg of As(V) in a sample volume of 1 ml. An interference study for both species was made and the method was applied to the determination of As₂O₃ and As₂O₅ in a standard glass sample. (author). 29 refs.; 3 figs.; 5 tabs

[en] Purpose: To evaluate the pattern of failure after limited margin radiotherapy for glioblastoma. Methods and Materials: We analyzed 62 consecutive patients with newly diagnosed glioblastoma treated between 2006 and 2008 with standard fractionation to a total dose of 60Gy with concurrent temozolomide (97%) or arsenic trioxide (3%). The initial clinical target volume included postoperative T2 abnormality with a median margin of 0.7cm. The boost clinical target volume included residual T1-enhancing tumor and resection cavity with a median margin of 0.5cm. Planning target volumes added a 0.3- or 0.5-cm margin to clinical target volumes. The total boost planning target volume (PTV_boost) margin was 1cm or less in 92% of patients. The volume of recurrent tumor (new T1 enhancement) was categorized by the percent within the 60-Gy isodose line as central (>95%), infield (81-95%), marginal (20-80%), or distant (<20%). For comparison, an initial planning target volume with a 2-cm margin and PTV_boost with a 2.5-cm margin were created for each patient. Results: With a median follow-up of 12 months, radiographic tumor progression developed in 43 of 62 patients. Imaging was available for analysis in 41: 38 (93%) had central or infield failure, 2 (5%) had marginal failure, and 1 (2%) had distant failure relative to the 60-Gy isodose line. The treated PTV_boost (median, 140cm³) was, on average, 70% less than the PTV_boost with a 2.5-cm margin (median, 477cm³) (p < 0.001). Conclusions: A PTV_boost margin of 1cm or less did not appear to increase the risk of marginal and/or distant tumor failures compared with other published series. With careful radiation planning and delivery, it appears that treatment margins for glioblastoma can be reduced.

[en] Arsenic trioxide (As₂O₃) can be used as a possible pharmaceutical alternative that augments radiofrequency (RF) ablation by reducing tumor blood flow. The aim of this study was to assess the effect of intraarterial and intravenous administration of As₂O₃ on RF-induced ablation in an experimentally induced liver tumor. VX2 carcinoma was grown in the livers of 30 rabbits. As₂O₃ (1 mg/kg) was administered through the hepatic artery (n = 10, group A) or ear vein (n = 10, group B), 30 minutes before RF ablation (125 mA ± 35; 90 ± 5 degrees Celsius). As a control group, 10 rabbits were treated with RF ablation alone (group C). RF was intentionally applied to the peripheral margin of the tumor so that ablation can cover the tumor and adjacent hepatic parenchyma. Ablation areas of the tumor and adjacent parenchymal changes among three groups were compared by the Kruskal-Wallis and Mann-Whitney U test. The overall ablation areas were 156 ± 28.9 mm² (group A), 119 ± 31.7 (group B), and 92 ± 17.4 (group C, p < 0.04). The ablation area of the tumor was significantly larger in group A (73 ± 19.7 mm²) than both group B (50 ± 19.4, p = 0.02) and group C (28 ± 2.2, p < 0.01). The ratios of the tumoral ablation area to the overall ablation area were larger in group A (47 ± 10.5%) than that of the other groups (42 ± 7.3% in group B and 32 ± 5.6% in group C) (p < 0.03). Radiofrequency-induced ablation area can be increased with intraarterial or intravenous administration of As₂O₃. The intraarterial administration of As₂O₃ seems to be helpful for the selective ablation of the tumor.

[en] Granulates are produced from As₂S₃, As₂O₅, alloys of selenic/tellurium, or compound systems based on chalcogenides. For this purpose the original substance consisting of As and Se is filled as loose material into the reactor of an equipment that has got an electric heating and a mixer-settler for homogenizing the melting phase of the mixture. In this way a product is formed meeting the requirements for a photoconductor compound to be evaporated in high-vacuum. (DG)

[en] The Indian crested porcupine, Hystrix indica, is widely distributed in the irrigated forests of Punjab, Pakistan and causes serious damage to trees, nursery stocking, field crops and vegetables. Field trials were conducted to determine the efficacy of aluminium phosphide (Phostoxin, 3g tablets) and arsenic trioxide bait (at 2.5g per apple) against the porcupine in a forest plantation. For fumigation with phostoxin, tablets were used at the rate of four, five, six and seven tablets per den. Observations showed that four tablets were ineffective, five and six tablets provided partial control, while seven tablets provided complete control of porcupines. Baiting with arsenic trioxide also resulted in 89 % reduction of the porcupine population occupying the treated dens. (author)

[en] Published in summary form only

[en] Residues of neoasozine in rice grain were determined by neutron activation and colorimetric techniques. Twice application of the chemical before flowering did not lead to any increased residue level while 4-times application resulted in significant increase in the residue level up to 0.54 - 0.75 mg As₂O₃/kg. The partition ratio of arsenic residues into polished rice grain and bran was 73 : 27 in 100 % polishing while most of the residues in the bran was transferred to oil cake fraction during solvent extraction, reaching up to 2.9 mg As₂O₃/kg. The neutron activation technique was advantageous because of its high sensitivity and the smaller sample amounts required for analysis. (author)

[en] I. The chemistry of the bipentaborane 2,2'-(B₅H₈)₂ is investigated to some extent. Pyrolysis of 2,2'-(B₅H₈)₂ resulted in the formation of non-volatile solid boron hydrides and hydrogen. Treatment of 2,2'-(B₅H₈)₂ with bromine in the presence of AlBr₃ resulted in the isolation of 1,1'Br₂-2,2'-(B₅H₇)₂. Reaction of 2,2'-(B₅H₈)₂ with deprotonating agents resulted in the formation of the corresponding anions. Reaction of 2,2'-(B₅H₈)₂ with diborane followed by acidification afforded n-B₉H₁₅ and B₁₀H₁₄ in moderate yield. II. Reaction of K⁺B₉H₁₂S^- with potassium polyselenide resulted in the isolation of stable white crystals of B₉H₉SSe. Treatment of B₉H₉SSe with one equivalent of base in methanol gave the unstable heteroborane B₈H₉(OCH₃)SSE and treatment with two equivalents of base afforded yellow crystals of B₇H₉SSe. Reaction of K⁺B₉H₁₂S^- with arsenic trioxide in aqueous basic solution gave the electron-rich heteroborane, B₈H₈As₂S in moderate yield. This resulted in the isolation and identification of Et₃N.BH₃ and the new metalloborane B₇H₇As₂SCo(C₅H₅). Treatment of B₁₀H₁₁Se^- with As₂O₃ resulted in the isolation of the stable nido-heteroborane B₈H₈As₂Se in low yield. Reaction of B₇C₂H₁₃ with potassium polyselenide gave the arachno selenacarborane B₇H₂C₁₁Se in low yield. The structure of the new heteroborane is proposed on the basis of ¹¹B and ¹H nmr spectra. Reaction of B₇C₂H₁₃ with AsCl₃ resulted in the isolation of white stable crystals of B₇C₂H₉As₂ in 40 percent yield

[en] A series of glasses excavated in the Albanian city of Lezha (ancient Lissos) were analyzed by the combined PIXE-PIGE method in air and by source-excited XRF. The analysis revealed two types of glass that can be identified as facon de Venise glass and its subsequent younger phase, produced by chemically purer components and using As₂O₃ as decolorant.

No abstract available