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We have studied 33 patients with a large ventricular aneurysm complicating an anterior myocardial infarction. The features of myocardial infarction progressing towards an aneurysm were no previous history of coronary disease, severe infarction as shown by the severity of pain and the presence of pericardial rub and heart failure, and large increase in serum levels of cardiac enzymes. A large aneurysm usually follows a large infarction resulting from the total or partial occlusion of the left anterior descending artery, which is involved alone in about half the patients and is associated with lesions of the circumflex and right coronary arteries in the other half. In most cases, standard radiography showed an abnormal cardiac configuration, but in 7 patients (21%) there was no radiological evidence of aneurysm. ST segment elevation (mean 2.7 mm) was reported in all subjects but one. Heart failure was present in most patients and was an indication for surgical treatment in one-third of the patients. A large aneurysm was not a contraindication to operation even when at angiography the aneurysm seemed to occupy almost all the left ventricle. Twenty-one patients were operated upon for resection of the aneurysm with a mortality rate of 14 per cent. [ABSTRACT FROM PUBLISHER]

We report on recent developments of the atmospheric pressure OMVPE of InP and InGaASP using trimethylindium, trimethylgallium, phosphine and arsine. The use of diffuser organometallic sources significantly increased the accuracy of quaternary composition control. This control was achieved in the whole range of quaternary light emitting wavelengths from 1.20 micrometers up to the ternary GaInAs limit. The influence of the carrier gas was further investigated: device-quality heterostructures were obtained for either of the three carrier gases hydrogen, helium and argon. The experimental conditions for growing quaternaries with a given composition agree well with a simple model. This work has permitted the realization of 1.3 micrometer laser heterostructures with low threshold current density. [ABSTRACT FROM AUTHOR]

We have grown GaAs on silicon substrates by organometallic chemical vapor deposition and we have studied the autodoping of the GaAs layers by silicon during the growth. The epitaxies were performed on GaAs wafers and on GaAs/Si wafers side by side during the same run. By measuring the atomic silicon concentration on the grown layers, we show that a contamination of silicon occurs during the growth process via SiH4 formation and diffusion from the substrate. We propose a model to explain the contamination of the GaAs layers by the silicon substrate. [ABSTRACT FROM AUTHOR]

Research was conducted to determine the role in selectivityof uptake, translocation, metabolism and ALS (acetolactatesynthase) activity of rimsulfuron in two maize (Zea maysL.) hybrids (‘Cargill 2127’, tolerant, and ‘Pioneer 3897’,sensitive) grown at temperatures of 14°C and 21°C. Fortyeight hours after treatment (HAT), uptake of rimsulfuronwas 40% and 67% in ‘Pioneer 3897’, and 26% and 43%in ‘Cargill 2127’ at 14°C and 21°C, respectively. Neithertotal translocation nor allocation of rimsulfuron in variousorgans differed greatly between the hybrids. Translocationof 14C-rimsulfuron was greater at 21°C (53%) than at 14°C(23%), 48 HAT. In ‘Pioneer 3897’ over 65% and 30% ofthe total 14C-activity present in plant extracts was recoveredas the parent compound within 24 HAT, at 14°C and21°C, respectively. However, in ‘Cargill 2127’ detoxificationof rimsulfuron was not affected by temperature, and27% of the 14C-total activity was recovered as the parentcompound. Crude ALS extracts from ‘Pioneer 3897’ and‘Cargill 2127’ maize seedlings were treated with variousdoses (0.001, 0.005, 0.01, 0.1 and 1.0 μM) of rimsulfuron.Based on ALS specific activity, I 50 values differed sligthlybetween the two hybrids (I 50 ‘Pioneer 3897’ = 0.091 μMand I 50 ‘Cargill 2127’ = 0.142 μM). These results suggestthat the mechanism of rimsulfuron tolerance in maizecould be mainly explained by differential herbicide uptakeand detoxification, with translocation and ALS sensitivityhaving little effect on differential tolerance of these maizehybrids to rimsulfuron. On the other hand, the greateruptake and translocation of rimsulfuron at 21°C, comparedto 14°C, could explain the observed herbicide injury inmaize at high temperatures under field conditions.

The response of eighteen maize (Zea mays L.) hybrids to rimsulfuron [(1-(4-6-dimetoxipyrimidin-2-yl))-3-((ethylsulfonyl)-2-pyridylsulfonyl) urca] was evaluated under field conditions on the campus of Université Laval (Québec, Canada). These hybrids were selected based on a wide range of maize heat unit (MHU) requirements. The response of hybrids to post emergence treatment of rimsulfuron (20, 40, and 60 g a.i ha-1) was compared to an untreated hand-weeded control. The data recorded included visual shoot phytotoxicity, plant height, and above-ground dry matter. Visual phytotoxicity varied among the same hybrid with respect to the date of evaluation, from 32% to 46% in 1992, and from 11% and 23% in 1993. According to Principal Component Analysis (PCA), the first component accounted for 820/0 ofthe total variance, with high weights ('eigenvectors') on the visual phytotoxicity 14, 21, 28, and 35 DAT. This signified that comparision among hybrids for sensitivity to rimsulfuron could be carried out by means of visual scores 14, 21, 28 or 35 DAT. Hybrids react differently to different doses of rimsulfuron. Some hybrids tolerated a high dose ofrimsulfuron, while others were severely injured at a low dose. A hybrid phytotoxicity score (HPS), based on the mean of visual scores at 14, 21, 28 and 35 DAT, averaged across all three application doses, was used to group the hybrids into three categories according to their degree of tolerance: I:Tolerant (HPS < O); II. Moderately tolerant (HPS ≡ O); and III.Sensitive (HPS > O). Tolerance to rimsulfuron varied also depending on genotypes which was positively correlated to MHU requirements. Hybrids of zone 1 of Québec (> 2700 MHU) were more tolerant (based on the HPS) than hybrids of zone 2 (2500 to 2700 MHU) and zone 3 (2300 to 2500 MHU). Key words: herbicide tolerance, phytotoxicítyscore, sulfonylurcas, maize heat units, multivariate analysis.

The effect of temperature (T), relative humidity (RH), and growth stage (GS) of six field maize hybrids on the level of tolerance to rimsulfuron [N-((4,6-dimethoxypyrimidin-2-yl) aminocarbonyl)-3-(ethylsulfonyl)-2-pyridincsulfonamide] applied at 20, 40 and 60 g a.i ha-l were evaluated. The hybríds tested are adapted to three climatic zones of Québec, Canada (zone 1: >2 700 maize heat units (CHU); zone 2: 2500 to 2 700 CHU; zone 3: 2 300 to 2 500 CHU).Two hybrids of each zone were considered. Three experiments were carried out under growth chamber and glasshouse conditions. Corn response to rimsulfuron doses was linear. Hybrids of zone 1 were more tolerant to rimsulfuron than hybrids from zones 2 and zone 3.Dry weight reduction of hybrids (DWR as a percentage of the untreated control 14 days after treatment) varied according to the dose from 22% to 29%, 31 % to 35%, and 36% to 38% in zones 1, 2, and 3, respectively. The response of maize hybrids to increasing temperaturewas linear, and the DWR was 12%, 28%, and 51 % at 14°C, 21 °C, and 28°C, respective1y. Injury to maize hybrids grown under 60% and 75% RH averaged 31 % and 37% DWR, respectively. Corn plants treated at the 2- to 3-leaf growth stages showed, in general, more sensitivity to rimsulfuron than those treated at the 4- to 5- leaf stage. These results confirmthat both environmental conditions and maize genotypesplay an important role in the injury caused by rimsulfuron. Key words: herbicides, sulfonylurea, rimsulfuron, field maize hybrids, tolerance, environmental conditions. Abbreviations: CHU, maize heat units; T. temperature;RH, relative humidity; GS, growth stage; DWR, dry weightreduction.

Se realizaron experimentos en el campus de la UniversidadNacional de Colombia, en Santafé de Bogotá, para estudiar lanaturaleza de la genética de la tolerancia del herbicidarimsulfuron en el maíz (Zea mays L.). En una primera etapa, se seleccionaron lineas puras de maíz tolerantes y sensibles al herbicida, para ser cruzadas posteriormente. En una segunda etapa, dos lineas, una tolerante ('L-34 ') y otra sensible ('L-31'), fueron estudiadas, junto con sus progenies F l' F2' y retrocruzas al padre tolerante y al padre sensible, con el fin de determinar, bajo dos ambientes, las bases genéticas de la tolerancia al rimsulfuron. Las plantas fueron tratadas con una dosis del herbicida de 60 g i.a. ha". Esta dosis causó 60% de fitotoxicidad (daño visual) a la línea sensible. La fitotoxicidad visual y el porcentaje de reducción de la altura y del peso seco de la parte aérea de las plantas, expresado como porcentaje del testigo no tratado, fueron usados como indices de tolerancia al rimsulfuron. Los resultados obtenidos del análisis de generación de media, indican que la tolerancia al rimsulfuron en el maíz se encuentra, principalmente, bajo el control genético de efectos aditivos y de dominancia. Losresultados basados en el análisis Mendeliano y los basadosen comparaciones entre los padres y las poblaciones F1 derivadas de cruzamientos de lineas puras sensibles y tolerantes al herbicida, también, sugieren efectos de dominancia, orientados hacia la tolerancia. Todas las poblaciones F1 sufrieron un daño menor al 18% (evaluación visual). Los valores estimados de herabilidad fueron, en general, negativos. Cuando la evaluación visual fue usada como un índice de tolerancia, los valores estimados del número mínimo de genes en segregación (índice de Castle- Wright), fue de 1,3. Experiments were conducted on the campus of the NationalUniversity of Colombia, at Bogotá, Colombia to study thenature of genetic tolerance to rimsulfuron herbicide in maize(Zea mays L.). In a first step, sensitive and tolerant lines were selected and crossed. In a second step, two inbred lines, one tolerant ('L-34') and one sensitive ('L-31 '), were studied with their F1 F2 and backcross progenies to determine the genetic basis for tolerance to rimsulfuron in two environments. Plants were sprayed with 60 g a.i. ha" rimsulfuron. This dose caused 60% injury (visual phytotoxicity) in the sensitive lineo Visual phytotoxicity, and height and shoot dry weight reduction, both expressed as percentage of check plants, were used as indices of tolerance to rimsulfuron. Results obtained from generation mean analysis indicated that tolerance to rimsulfuron is mainly under the genetic control of additive and dominance effects. Results from the Mendelian analysis and from comparisons between parents and F1 populations derived from tolerant and sensitive inbred lines crosses, also suggest dominance effects oriented toward tolerance. All F, populations were injured less than 18% (visual phytotoxicity). The estimates ofheritabilities were in general negative. When visual phytotoxicity was used as an index of tolerance to rimsulfuron, estimate of the minimum number of segregating factors (Castle- Wright index) was 1.3.

Transport of linuron, imidacloprid and bromide along soil columns and field lysimeters. Undisturbed soil columns (65 cm high x 15 cm diam.) were used in a greenhouse experiment to study the effect of rainfall and mode of application on leaching pattern of linuron and imidacloprid. Two simulated rainfall amounts (288 mm and 496 mm) distributed over a one month period and two modes of application (sole or combined application of the two pesticides) were studied. Linuron did not leach below 65 cm of the soil columns. Imidacloprid was leached in trace amount below 65 cm soil columns (less than 1,5/ of applied a.i.). Under field conditions, linuron was detected in percolated water below 1 m depth lysimeters at concentration less than 4 microg per liter. Imidacloprid was detected at concentration less than 3 microg per liter in percolated water below 1 m depth. Bromide ion was leached at 62 to 88/ of the applied mass on soil columns or field lysimeters. The elution pattern of bromide ion suggests the presence of preferential flow paths.

Context: Slime is a slow-flowing material with viscoelastic properties which is attractive to children. Its preparation is based on the crosslinking of polyvinyl alcohol, polyvinyl acetate or starch with boric acid. Objectives: The goal of this study was to describe the adverse effects of Slime. Materials and methods: This is a descriptive retrospective study of cases of exposure reported to French Poison Control Centres between January 2014 and May 2018. The following parameters were used: age and sex, date and circumstances of exposure, symptoms and severity. Results: Two hundred and eight (208) cases of exposure were recorded, 93 cases happened in 2017, and 88 cases in the first four and a half months of 2018. The average age was of 8 years old; 190 patients were younger than 15. Fifty-seven percent (57%) were female. Regarding routes of exposure, 168 were oral, 30 cutaneous, eight ocular, one inhalation and one ear exposure. Eighty-two (82) patients were symptomatic, including 81 cases of low severity and one of average severity (keratitis). All cases lead to recovery. Conclusion: No significant adverse health effects are expected to develop if only small amounts are swallowed; making Slime with home ingredients is a potential cause of boric acid exposure that must be supervised by adults. [ABSTRACT FROM AUTHOR]