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In this study, detonation cell sizes of methanol-oxygen mixtures are experimentally measured at different initial pressures and compositions. Good agreement is found between the experiment data and predictions based on the chemical length scales obtained from a detailed chemical kinetic model. To assess the detonation sensitivity in methanol-oxygen mixtures, the results are compared with those of hydrogen-oxygen and methane-oxygen mixtures. Based on the cell size comparison, it is shown that methanol-oxygen is more detonation sensitive than methane-oxygen but less sensitive than hydrogen-oxygen. [ABSTRACT FROM AUTHOR]

To assess the effect of the anti–marine-borer timber preservative CCA (a pressure-impregnated solution of copper, chromium, and arsenic compounds) on nontarget epibiota, fouling community development was investigated. Panels of Scots pine treated to target retentions of 12, 24, and 48 kg CCA per m3 of wood (covering the range of retentions recommended for marine use) plus untreated controls were submerged at seven coastal sites (Portsmouth, UK; La Tremblade [two sites], France; Ria Formosa, Portugal; Sagres, Portugal; Kristineberg, Sweden; Athens, Greece). The fouling community on the surfaces of the panels was assessed both qualitatively and quantitatively after 6, 12, and 18 months of exposure. Multivariate statistical methods were used to compare community structure between panel treatments. Panels treated to the three CCA loadings supported very similar fouling assemblages, which in most cases had higher numbers of taxa and individuals than assemblages on untreated panels. No detrimental effects on epibiota due to CCA preservatives were detected at any of the treatment levels at all seven exposure sites, suggesting that the range of environmental conditions at the sites had no bearing on preservative impact on fouling biota. Differences in community structure between CCA-treated and untreated panels may be due to enhanced larval settlement on CCA-treated timber by some species as a result of modifications to the surface properties of the timber by the preservative. Possible reasons for the higher numbers of certain species on the surface of CCA-treated panels are discussed. [ABSTRACT FROM AUTHOR]

Complex formation of hairpin-producing heptadeoxynucleotide 5"-d(GCGAAGC) with aromatic molecules: acridine dye proflavine and anthracycline antibiotic daunomycin was studied by one-dimensional 1H NMR and two-dimensional correlation 1H–1H (2D-TOCSY, 2D-NOESY), 1H–31P (2D-HMBC) NMR spectroscopy (500 and 600 MHz) in aqueous solution. Concentration and temperature dependences for the chemical shifts of ligand protons were measured, molecular models of equilibrium in solution were developed, and equilibrium thermodynamic parameters for the formation of intercalation complexes were calculated. Spatial structures of dye and antibiotic complexes with the heptamer hairpin were constructed on the basis of 2D-NOE data and the calculated values of limiting chemical shifts of ligand protons. [ABSTRACT FROM AUTHOR]

Taeniolella rudis, with secondary sympodioconidia, is illustrated and described and its taxonomic assignment evaluated. A second new species, Taeniolella longissima, is described and illustrated. The ecological role of these fungi in the colonization of wood in freshwater habitats is discussed. [ABSTRACT FROM AUTHOR]

Self-association of hexadeoxynucleotide 5"-d(TpApCpGpTpA) and its complexation with antitumor antibiotic daunomycin were studied by one- and two-dimensional homonuclear 1H NMR spectroscopy and heteronuclear 1H–31P NMR spectroscopy in water–salt solution. The concentration and temperature dependences of proton chemical shifts of the hexadeoxynucleotide and the ligand were measured, and equilibrium constants and thermodynamic parameters of corresponding reactions were calculated on this basis using models for the formation of hexadeoxynucleotide duplex and its complex with the antibiotic. The spatial structure of daunomycin–d(TACGTA)2complex in solution was calculated using X-PLOR software on the basis of 2D NOE spectral data and the limit values of proton chemical shifts of the ligand. Comparative analysis of different intermolecular interactions in sequence-specific binding of the antibiotic to the DNA fragment was carried out. [ABSTRACT FROM AUTHOR]

Complexation of the anthracycline antibiotic daunomycin (DAU) with self-complementary desoxyhexanucleotides with different base sequences in the chain, 5′- d(CGTACG) and 5′- d(CGCGCG), is studied in aqueous solution. Homonuclear 2D-1H NMR spectroscopy (TOCSY and NOESY) and heteronuclear 1H–31P NMR spectroscopy (HMBC) are used for complete assignment of the nonexchangeable proton resonances and the phosphorus signals and for qualitative determination of preferable DAU binding sites, respectively. Daunomycin is preferably intercalated into the first d(CG)-site of each hexanucleotide, and the aminosaccharide ring of DAU lies in the minor groove of the hexamer duplex, partly overlapping the third base pair. Quantitative analysis of DAU complexation with desoxyhexanucleotides was done by analyzing the concentration and temperature dependences of the DAU proton chemical shifts; the equilibrium reaction constants and the thermodynamic parameters of the formation of the 1:1, 1:2, 2:1, and 2:2 DAU complexes with hexamers, as well as the limiting values of the DAU proton chemical shifts were determined in aqueous solution. The antibiotic preferably binds with the triplet sections of the nucleotide sequence containing two neighboring CG-pairs of nitrogen bases flanked by the AT-pair in 5′- d(CGTACG) compared to the triplets consisting of a sequence of three CG-pairs in the 5′- d(CGCGCG) hexamer. The specific binding of daunomycin depends on the character of the hydrophobic interactions of the aminosaccharide ring of the antibiotic in the minor groove of the DNA double helix. Calculations have been carried out to determine the most probable spatial structures of the 1:2 DAU–desoxyhexanucleotide complexes; the results agree well with X-ray diffraction data. [ABSTRACT FROM AUTHOR]

The happy ending of the Franklin's Tale is contrived by the tale's narrator in ways which should cause us to be suspicious of both his values and motives. The tale in effect "undoes" itself. At the end we see its principal characters carrying on as if the whole unpleasantness has never happened, while our attention is directed away from the blameworthy behavior we have seen and toward the final state of happiness. The tale's incapacity to "move forward" is just one of the reasons why we should be suspicious of its optimism. What we see if we look beyond the triumphant phrases is a world which is isotated and isolating, weighed down and limited by the physical, the material, the sensual. The Franklin's Tale is more than anything else about man's vulnerability to himself. It is about the intimate connection between man's identity – his sense of himself –and his body. It is about the subtle and potent ways in which that intimate association between self and body weakens and compromises man's moral strength and vision and his capacity for spiritual fulfillment. And it is about man's capacity to delude himself about the well-being of his soul and world as long as he is assured of the well-being of his body. [ABSTRACT FROM AUTHOR]

This paper examines abnormal stock returns in the three years surrounding relatively large changes in dividends announced during the 1971 to 1990 period. The main results are that statistically and economically significant negative post-announcement abnormal returns of - 11% and - 17% over the post-announcement year are found for firms which decrease dividends and those which omit their dividends. Firms resuming and firms increasing dividends do not exhibit significant abnormal returns, on average, over the post-announcement year. The pattern of lagged price adjustment to negative dividend change information differs from that reported for 'earnings surprise" firms in important respects. While the dividend change firms do exhibit returns behavior consistent with year-to-year returns momentum, differences in prior year returns do not explain the differences in returns over the post-announcement period. [ABSTRACT FROM AUTHOR]

This paper presents the results of our study of the complexation of the antibiotic daunomycin with desoxytetranucleotide 5’-d(CpGpCpG) in aqueous salt solution by one- and two-dimensional (2D-TOCSY and 2D-NOESY)1H NMR spectroscopy (500 MHz). The concentration and temperature dependences of the proton chemical shifts of molecules were measured and used to calculate the equilibrium reaction constants, the relative contents of different types of complex as functions of concentration and temperature, the limiting values of the proton chemical shifts of daunomycin in various complexes, and the thermodynamic parameters of complexation δH and δS. It is concluded that the triplet nucleotide sequences are the preferable sites at which daunomycin is attached. The binding of the second daunomycin molecule to both single-stranded and duplex forms of tetramer is markedly anticooperative. This is explained by the presence in the antibiotic of a positively charged amino sugar residue creating steric hindrances for the attachment of the second antibiotic molecule to the short tetranucleotide sequence. The most plausible spatial structure of the 1:2 complex of antibiotic with desoxytetranucleotide is constructed using the calculated values of the induced proton chemical shifts of daunomycin and 2D-NOE data. [ABSTRACT FROM AUTHOR]

The ketotic effects of both glucocorticoid and growth hormone were assessed in normal man. Experimental protocols, previously shown to induce marked ketosis in diabetic man, were utilized to explore the metabolic effects of these two stress hormones in subjects with normal insulin secretory capacity. Glucocorticoid was administered orally as 1 mg of dexamethasone at 24 and 8 h prior to study. Growth hormone was administered subcutaneously at a dosage of 1 mg, 12 h prior to study. During the 90-min study of the ketotic activity of these hormones, plasma nonesterified fatty acids were acutely increased by heparin administration to support hepatic ketogenesis. This technique permitted an assessment of the ketotic activity of glucocorticoid and growth hormone independent of their lipolytic activity. The results of this study demonstrate that glucocorticoid may cause minimal hyperketonemia in spite of hyperinsulinemia in normal man. However, this effect is accompanied by a glucocorticoid-induced instability in basal ketone body and nonesterified fatty acid concentration. In contrast, no effect of growth hormone on plasma ketone body concentration or insulin levels was observed. These results in normal man contrast to the marked ketosis previously induced by these two stress hormones in diabetic man. [ABSTRACT FROM AUTHOR]

The trapeziometacarpal joint is particularly prone to osteoarthritis due to the great amount of stress applied with everyday activities with the hands. In this essay, radiologic assessment and staging of "basal joint" osteoarthritis, treatments based on radiologic staging and intraoperative findings, and surgical complications are described. [ABSTRACT FROM AUTHOR]

To define the quantitative relationship between peripheral nerve structure and function imposed by endoneurial oedema in the diabetic state, we determined values for sural nerve hydration structure as measured by magnetic resonance spectroscopy, and for neurological function with scores for nerve conduction properties (NCV-score), neuropathic symptoms (NS-score), and examination signs (NE-score). The coefficient of sural nerve hydration was elevated to 30±6% ( p<0.05) in 79 symptomatic neuropathic diabetic subjects with an average of 15 years of diabetes mellitus, compared to a value of 25±3% in 72 non-diabetic control subjects. In contrast, in 75 asymptomatic diabetic subjects with an average of 6 additional years of diabetes, the mean hydration coefficient was only 28±5% ( p<0.05). A nerve hyperhydration state was identified with a prevalence of 25% within the asymptomatic group characterized by nerve hydration greater than the 95th percentile, early changes in nerve electrophysiology and neurological examination, but with no symptomatology of neuropathy. Stratification of the symptomatic neuropathic group by worsening nerve electrophysiology, demonstrates a coincident deterioration in neurological examination (RR=5.39 at maximum NCV-score), and neuropathy symptomatology (RR=4.80 at maximum NE-score). The present data are consistent with the hypothesis that endoneurial oedema initiates deterioration sequentially in nerve electrophysiology, followed by abnormal findings on neurological examination, preceding the patient's final perception of symptomatic stocking-glove peripheral diabetic neuropathy. [ABSTRACT FROM AUTHOR]

This study examined the feasibility of normalizing the plasma insulin profile in five insulin deficient diabetic males. Acute meal-related increases in plasma free insulin concentration were achieved by administering short-acting insulin intraperitoneally with a pre-programmed portable rotary splenoid driven pump. This insulin response was compared to that achieved when short-acting insulin was injected subcutaneously 15 minutes prior to each meal. After intraperitoneal insulin maximal plasma free insulin concentration was observed within 45 minutes of administration, and averaged 40±13 mU/l (±SEM) for breakfast, 30±13 mU/l for lunch, and 36±13 mU/l for supper. This acute rise was followed by a gradual decline in plasma free insulin concentration, simulating a normal plasma insulin profile. With subcutaneously injected insulin, approximately the same maximal plasma free insulin concentration was obtained as observed with intraperitoneal insulin, but it was delayed 116 minutes following injection. These data suggest that intraperitoneally delivered insulin is rapidly absorbed and may normalize the peripheral plasma free insulin concentration, at least during short-term studies. [ABSTRACT FROM AUTHOR]

The relationship between non-esterified fatty acid (NEFA) mobilization and hepatic conversion to plasma triglycerides (TG), as modulated by diazoxide-induced effects upon endogenous catecholamine, glucagon, and insulin secretion, was examined in vivo in the rat. Thyrotropin (TSH)-induced NEFA mobilization provided the control study. - In all control experiments, TSH (1.5 IU/ 100 g) induced a 110% increase in NEFA availability, which was associated with a subsequent 52% increase in plasma TG concentration and a 73% increase in plasma ketone bodies. Following diazoxide administration (30 mg/kg), endogenous secretion of both catecholamines and glucagon was observed, resulting in a comparable 100% increase in NEFA availability, with the appropriate ketonaemic response. However, in contrast to the control TSH study, plasma triglyceride concentration did not increase. This suppression was secondary, at least in part, to a direct 40% inhibition of hepatic secretion of triglycerides. - Although plasma NEFA concentration is an important determinant of plasma triglyceride levels, the concurrent concentration of endogenous catecholamines, glucagon, and insulin modulate the hepatic conversion of NEFA to triglycerides in vivo. [ABSTRACT FROM AUTHOR]

Norepinephrine was infused for 60 minutes in high physiological concentration (0.08 μg/ kg/min) into seven insulin dependent diabetic subjects with no demonstrable endogenous insulin secretion and into seven normal subjects. Insulin dependent diabetic subjects had a stable, free insulin concentration of 23±5 μU/ml which was unaffected by norepinephrine infusion. In the normal subjects, norepinephrine induced an initial inhibition of insulin secretion which lasted for approximately 20 minutes. Norepinephrine infusion caused a rapid increase in both ketone body and glucose concentrations but this response did not differ between the two groups. In contrast, plasma nonesterified fatty acid and triglyceride concentrations were increased significantly more in the normal than in the diabetic subjects. The increase in plasma glucagon concentrations was similar in the two groups of subjects. The cause of the differential metabolic response to norepinephrine between the normal and diabetic groups was not resolved, but may be related, at least in part, to suppression of endogenous insulin secretion in the normal subjects. [ABSTRACT FROM AUTHOR]

The magnitude and direction of the lipolytic and ketogenic responses following exogenous glucagon administration is controversial and consideration of the possible role of endogenous insulin secretion upon these events has not been clarified. The present study examines the role of endogenous insulin secretion in modulating the net lipolytic and ketogenic activity of glucagon. Three groups characterized by different levels of endogenous insulin secretory capacity were studied. In all three groups, the responses in plasma insulin, betahydroxybutyrate, and free fatty acids were observed following bolus administration of 1.0 μg/kg glucagon. In the obese subjects with increased endogenous insulin secretion, glucagon administration resulted in a decline below basal levels of both free fatty acid and betahydroxybutyrate. In the diabetic subjects with no demonstrable endogenous insulin secretion, glucagon administration was followed by a rise in plasma free fatty acids and an exaggerated rise in plasma betahydroxybutyrate. The normal control group exhibited a response in betahydroxybutyrate midway between the obese and diabetic groups. These observations support the thesis that the magnitude of endogenous insulin secretion modulates the lipolytic and ketogenic actions of glucagon in man. [ABSTRACT FROM AUTHOR]