H2s in natural gas: tolerance of some national acceptance tests

Traditionally, limits on H₂S concentration in town gas have been fixed on the basis of non-discoloration of lead acetate paper when this is exposed to the gas in a specified manner. Most countries specify their own particular apparatus and conditions for carrying out this test. The limiting concentration of H₂S which produces a positive discoloration of the lead acetate paper was investigated with special reference to the U.K., French and German national gas acceptance tests, using Dutch natural gas in both the saturated and dry condition in every case. H₂S was introduced into the gas at a controlled rate by a dynamic line blending procedure. The actual concentration of H₂S present was checked by an automated version of the methylene blue colorimetric procedure. The U.K. tests gave borderline fails at 1.3 and 1.2 ppm for dry and saturated gas, respectively. These results differ markedly from those obtained with the French and German test methods. It may be inferred, therefore, that the maximum acceptable H₂S concentration in gas is best fixed by a numerical limit, which is in line with true technical needs, rather than by a qualitative procedure which can be different for different parts of the same distribution system.     

Synthesis of Alkyl Sulfur-Functionalized Oleic Acid-Based Polymethacrylates and Their Application as Viscosity Index Improvers in a Mineral Paraffinic Lube Oil

This work describes the synthesis of alkyl sulfur-functionalized polymethacrylate-based Viscosity Index Improvers (VII) derived from oleic acid (OLA) for mineral paraffinic lubricating oils. In this strategy, OLA was first quantitatively ramified by alkyl thiols containing long aliphatic chains through thiol-ene coupling as demonstrated by ¹H NMR spectroscopy with the complete consumption of OLA internal double bonds. The resulting alkyl sulfur-functionalized OLA-based derivatives were methacrylated through Steglich esterification in order to afford highly suitable hydrophobic OLA-based monomers which, as far as we know, have not been described yet in the current literature. High polymethacrylate molecular weights were reached through radical polymerization despite the long alkyl pendant chains contained in their backbones. Finally, the resulting alkyl sulfur-functionalized OLA-based polymethacrylates have been blended in a mineral paraffinic oil (MPO) of reference at 5 wt% and evaluated as VII. Rheological measurements revealed that polymer thickening powers were significantly improved in oil with temperature and promoted by increasing the pendant alkyl thiol contained in polymer backbones. Moreover, the viscosity index of MPO was significantly improved with the addition of both synthesized homopolymers which confirmed their efficiency as VII. In the meantime, these results have been compared with a previously reported polymer, the poly(2-[methacryloyloxy]ethyl oleate) (PMAEO), which demonstrated a lower VII efficiency compared with its analogous polymethacrylates containing an additional alkyl chain in their pendant chains.     

Occurrence of Loma cf. salmonae in brook, brown and rainbow trout from Buford trout hatchery, Georgia, USA

We retrospectively analysed the long-term treatment results (median 8 years) of 31 patients with macroprolactinoma. 17 patients were treated by pituitary surgery (group 1) followed by long-term dopamine agonist therapy whereas 14 patients received long-term dopamine agonist therapy alone (group 2). 2 patients of group 1 and 1 patient of group 2 had external pituitary irradiation because of progressive disease. The two groups were comparable with respect to age, gender and initial prolactin (PRL) levels. At the end of the observation period dopamine agonist dosage could be reduced by 50% in group 1 and by 39.3% in group 2. Pituitary function did not change substantially during therapy. Complete remissions (no visible tumour in CT or MRI, normal PRL levels under current dopamine agonist medication) were achieved in 23.5% of group 1 vs. 21.4% of group 2, partial remissions (reduction of PRL and tumour size) in 35.3% vs. 64.3%, stable disease in 23.5% vs. 7.1% and progressive disease in 17.7% vs. 7.1% (differences not significant). Visual field defects showed 28.4% remissions (complete and partial) in group 1 versus 50% in group 2. Dopamine agonist therapy could be stopped definitively in only 1 patient of group 2 with an invasive macroprolactinoma. Initial surgical reduction of tumour load followed by medical therapy does not seem to guarantee a better long-term outcome than dopamine agonist therapy alone if the patient responds to and tolerates dopamine agonist therapy. Surgery should be reserved for non-responders, drug-intolerant or non-compliant patients, and for those with acute severe neurological compromise.     

Ectopic teeth in the maxillary sinus: diagnosis and treatment

Several types of developmental anomaly of the teeth have been identified. In this article the authors describe three patients who presented with impacted teeth in the maxillary sinuses.     

Cytogenetic clonality analysis: typical patterns in myelodysplastic syndrome and acute myeloid leukaemia

The cell morphology and karyotype of bone marrow samples from 24 patients with myelodysplastic syndrome (MDS) and acute myeloid leukaemia (AML) were studied simultaneously with a combined technique of May-Grünwald-Giemsa (MGG) staining and fluorescence in situ hybridization (FISH) with chromosome-specific DNA probes. This enabled us to investigate cell lineage involvement in three malignant conditions: MDS (n = 12), leukaemia-transformed MDS (LT-MDS) (n = 5) and de novo AML (n = 7). In MDS we found blasts and often significant proportions of mature granulocytic and erythroid cells to be cytogenetically abnormal. Percentages of granulocytic and erythroid cells with cytogenetic aberrations were generally less than those of blasts. These data support the involvement of a transformed pluripotent stem cell that has retained maturation abilities. In two patients with chronic myelomonocytic leukaemia (CMMoL) the clonal involvement of monocytes was predominant. Results in the five patients with LT-MDS were similar to those in MDS. In the bone marrow of five of the seven de novo AML patients the cytogenetic abnormalities were restricted to the blasts and did not include the more mature granulocytic or erythroid populations. In the other two patients with AML, both with a t(8;21) and a loss of the Y chromosome, high percentages of mature neutrophils were cytogenetically abnormal. These patterns of clonal lineage involvement in MDS, LT-MDS, t(8;21) AML and AML appear typical and may be of clinical use, for example, for distinguishing LT-MDS from de novo AML in newly presenting patients.     

Influence of processing on the antioxidant capacity and bioactive compounds in jellies from different blackberry cultivars

The effect of thermal processing and the berry cultivar has been the subject of several studies, to serve as a basis for the least possible loss of bioactive compounds and antioxidant capacity. In Brazil, there are numerous blackberry cultivars under cultivation, and in this context, the aim of this work was to study how the bioactive compound contents and antioxidant capacity of blackberry jelly were influenced by the cultivars (Guarani, Brazos, Comanche, Tupy, Cherokee, Caingangue and Choctaw). Analysis was made of 7 fresh blackberry cultivars and 7 blackberry jelly formulations. Analysis of antioxidant activity, total phenolics, total anthocyanins and ascorbic acid was performed. It was verified that the contribution of the heat sensitive antioxidants compounds is considerable in all blackberry cultivars, and the degradation of these compounds was significantly different between the different blackberry cultivars. The Brazos and Caingangue cultivars stand out as undergoing the lowest losses in processing, resulting in jellies richer in bioactive compounds and higher antioxidant capacity.     

Point set morphological filtering and semantic spatial configuration modeling: Application to microscopic image and bio-structure analysis

High-level spatial relation and configuration modeling issues are gaining momentum in the image analysis and pattern recognition fields. In particular, it is deemed important whenever one needs to mine high-content images or large scale image databases in a more expressive way than a purely statistically one. Continuing previous efforts to incorporate structural analysis by developing specific efficient morphological tools performing on mesh representations like Delaunay triangulations, we propose to formalize spatial relation modeling techniques dedicated to unorganized point sets. We provide an original mesh lattice framework which is more convenient for structural representations of large image data by means of interest point sets and their morphological analysis. The set of designed numerical operators is based on a specific dilation operator that makes it possible to handle concepts like “between” or “left of” over sparse representations of image data such as graphs. Based on this new theoretical framework for reasoning about images, we are able to process high-level queries over large histopathological images, knowing that digitized histopathology is a new challenge in the field of bio-imaging due to the high-content nature and large size of these images.     

In situ hybridization on May-Grünwald Giemsa-stained bone marrow and blood smears of patients with hematologic disorders allows detection of cell-lineage-specific cytogenetic abnormalities

Bone marrow and blood from patients with acute myeloid leukemia and myelodysplastic syndrome were studied by simultaneous analysis of cell morphology and karyotype. A combined technique of May-Grünwald Giemsa (MGG) for cell morphology and fluorescence in situ hybridization (FISH) with chromosome-specific DNA probes for detection of cytogenetic aberrations allowed us to investigate cell-lineage-specific chromosomal abnormalities. We introduced video recordings to examine large numbers of cells. Briefly, evaluation was first performed on MGG slides, during which cell position and morphology were recorded on an S-VHS recorder. Subsequently, the same slides were used for FISH. This resulted in the identification of MGG-stained cells on the video screen and, at the same time, the interpretation of FISH signals in the fluorescence microscope. Specimens of bone marrow or blood samples from four patients with different hematologic malignancies were studied. One of these patients was studied before and after cytotoxic treatment. The gain or loss of chromosomes could be detected easily and morphologically assigned to the blasts in all patients and to a variable proportion of the myelomonocytic lineage in two patients, but not to the lymphocytes. Thus, this method provides new possibilities for investigating the clonality of hematologic malignancies.