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INDEX elevation

Taxa. Although many species show the classic inverse relationship between stomatal frequency and C02, not all species do so. Therefore, the sensitivity of the species of fossil leaves needs to be tested when selecting fossil species to work with. Moreover, since plants have morphological and physiological constraints that do not allow adjustment of stomatal numbers to infinitely high or low C02, plant species have species-specific response limits to C02 (Kiirschner et al. 1997). For instance, the nonlinearity of the stomatal index-elevation... [Pg.231]

ISO 4589-3 Plastics—Determination of Burning Behavior by Oxygen Index-Elevated-Temperature Test, ISO, Geneva, Switzerland, 1996. [Pg.807]

The mineral talc is extremely soft (Mohs hardness = 1), has good sHp, a density of 2.7 to 2.8 g/cm, and a refractive index of 1.58. It is relatively inert and nonreactive with conventional acids and bases. It is soluble in hydroduoric acid. Although it has a pH in water of 9.0 to 9.5, talc has Lewis acid sites on its surface and at elevated temperatures is a mild catalyst for oxidation, depolymerization, and cross-linking of polymers. [Pg.301]

Except as an index of respiration, carbon dioxide is seldom considered in fermentations but plays important roles. Its participation in carbonate equilibria affects pH removal of carbon dioxide by photosynthesis can force the pH above 10 in dense, well-illuminated algal cultures. Several biochemical reactions involve carbon dioxide, so their kinetics and equilibrium concentrations are dependent on gas concentrations, and metabolic rates of associated reactions may also change. Attempts to increase oxygen transfer rates by elevating pressure to get more driving force sometimes encounter poor process performance that might oe attributed to excessive dissolved carbon dioxide. [Pg.2139]

Over the years many attempts have been made to provide some measure of the maximum service temperature which a material will be able to withstand without thermal degradation rendering it unfit for service. Quite clearly any figure will depend on the time the material is likely to be exposed to elevated temperatures. One assessment that is being increasingly quoted is the UL 746B Relative Temperature Index Test of the Underwriters Laboratories (previously known as the Continuous Use Temperature Rating or Index). [Pg.186]

Eor amine-containing polymers, DMF is often a good choice of solvent. DMF can also be a good choice for polymers of higher carboxylic acid content. However, DMF does present some experimental difficulties. It must be run at an elevated temperature, typically 60°C, because of its viscosity. Also, because most polymers have a much lower refractive index response in DMF, the signal-to-noise ratio for a polymer in this solvent is diminished versus the same ratio for common acrylates in THF. [Pg.553]

Fig. 12.11 (a) Haring-Blum cell for throwing index measurement, in elevation and (b) Hull cell... [Pg.366]

The separation was carried out on a TSKgel Amide-80 column 4.6 mm i.d. and 25 cm long with a mobile phase consisting of a 80% acetonitrile 20% water mixture. The flow rate was 1 ml/min and the column was operated at an elevated temperature of 80°C. The saccharides shown were 1/ rhamnose, 2/ fucose, 3/ xylose, 4/ fructose, 5/ mannose, 6/ glucose, 7/ sucrose and 8/ maltose. The analysis was completed in less than 20 minutes. These types of separations including other biomonomers, dimers and polymers are frequently carried out employing refractive index detection. [Pg.186]

Ferritin is another protein that is important in the metabolism of iron. Under normal conditions, it stores iron that can be called upon for use as conditions require. In conditions of excess iron (eg, hemochromatosis), body stores of iron are greatly increased and much more ferritin is present in the tissues, such as the liver and spleen. Ferritin contains approximately 23% iron, and apoferritin (the protein moiety free of iron) has a molecular mass of approximately 440 kDa. Ferritin is composed of 24 subunits of 18.5 kDa, which surround in a micellar form some 3000-4500 ferric atoms. Normally, there is a little ferritin in human plasma. However, in patients with excess iron, the amount of ferritin in plasma is markedly elevated. The amount of ferritin in plasma can be conveniently measured by a sensitive and specific radioimmunoassay and serves as an index of body iron stores. [Pg.586]

Another common liver disease, alcoholic liver damage produced by moderate to heavy alcoholic intake, is also reflected by an elevation of the serum GOT and GPT activities. The serim glutamyl transferase activity is reported to be a sensitive index of alcoholic intake and can serve to monitor persons on alcoholic withdrawal programs (60). The LD-5 isoenzyme arises mainly from liver tissue, but has a short half-life (61), which is about 1/5 and 1/2 of the half life of the transaminases, GPT and GOT respectively. Some authors consider that a normal LD-5 isoenzyme activity in a jaundiced patient is sufficient evidence to exclude primary liver disease and that obstruction is probably responsible for the jaundice (62). In hemolytic jaundice the LDH-1 and 2 isoenzymes are elevated. [Pg.208]

Initial Pa/ U levels are more difficult to assess, primarily because there is no long-lived or stable isotope of protactinium that can be used as an index isotope. Edwards et al. (1997) analyzed a set of surface coral sub-samples younger than 1000 years by both °Th and Pa techniques. For all samples, Th concentrations were less than 100 p g so that initial °Th/ U values were negligible. Each sub-sample yielded °Th and a ages identical within analytical errors (Fig. 8), indicating that initial Pa/ U was negligible. This suggests that surface corals with typical Th values do not require corrections for initial Pa. Whether or not corals with elevated Th require such corrections is an open question. [Pg.377]

Demyelinated plaques, both active and inactive Active demyelinating plaques Oligoclonal bands of immunoglobulin G Elevated immunoglobulin G index Slowed nerve impulse conduction... [Pg.434]

Personal attributes such as physical inactivity and elevated body mass index (BMI) are associated with up to a twofold increase in the risk of colon cancer. Decreased bowel... [Pg.1343]

Creatine kinase, creatine kinase myocardial band Creatine kinase (CK) enzymes are found in many isoforms, with varying concentrations depending on the type of tissue. Creatine kinase is a general term used to describe the nonspecific total release of all types of CK, including that found in skeletal muscle (MM), brain (BB) and heart (MB). CK MB is released into the blood from necrotic myocytes in response to infarction and is a useful laboratory test for diagnosing myocardial infarction. If the total CK is elevated, then the relative index (RI), or fraction of the total that is composed of CK MB, is calculated as follows RI = (CK MB/CK total) x 100. An RI greater than 2 is typically diagnostic of infarction. [Pg.1563]

The SEC mechanism demands only an isocratic (constant composition) solvent system with normally a single solvent. The most frequently used organic solvents are THF, chloroform, toluene, esters, ketones, DMF, etc. The key solvent parameters of interest in SEC are (i) solubility parameter (ii) refractive index (iii) UV/IR absorbance (iv) viscosity and (v) boiling point. Sample solutions are typically prepared at concentrations in the region of 0.5-5 mg mL-1. In general an injection volume of 25-100p,L per 300 x 7.5 mm column should be employed. For SEC operation with polyolefins chlorinated solvents (for detector sensitivity and increased boiling point) and elevated temperatures (110 to 150 °C) are required to dissolve olefin polymer. HFIP is the preferred solvent for SEC analysis of polyesters and polyamides. [Pg.259]

The relationship of PbB level to systolic and diastolic blood pressure was determined in a study of 89 Boston policemen (race not specified) (Weiss et al. 1986, 1988). These policemen were under observation for health outcomes related to environmental work exposures (i.e., they had traffic exposure histories). After statistically adjusting for previous systolic blood pressure, body mass index, age, and cigarette smoking, high PbB level ( 30 pg/dL) was a significant (p=0.01) predictor of subsequent elevation in systolic blood pressure of 1.5-11 mm Hg in the working policemen with normal blood pressure. Low PbB level (20-29 pg/dL) was not a predictor of subsequent systolic blood pressure elevations. Diastolic pressure was unrelated to PbB levels. [Pg.51]

One of the most sensitive systems affected by lead exposure is the nervous system. Encephalopathy is characterized by symptoms such as coma, seizures, ataxia, apathy, bizarre behavior, and incoordination (CDC 1985). Children are more sensitive to neurological changes. In children, encephalopathy has been associated with PbB levels as low as 70 pg/dL (CDC 1985). The most sensitive peripheral index of neurotoxicity of lead is reported to be slowed conduction in small motor libers of the ulnar nerve in workers with 30-40 pg/dL lead in blood (Landrigan 1989). Other potential biomarkers of lead suggested for neurotoxicity in workers are neurological and behavioral tests, as well as cognitive and visual sensory function tests (Williamson and Teo 1986). However, these tests are not specific to elevated lead exposure... [Pg.322]

Taheri, S., Lin, L., Austin, D., Young, T. 8r Mignot, E. (2004). Short sleep duration is associated with reduced leptin, elevated ghrelin, and increased body mass index. PLoS Med. 1, e62. [Pg.335]

Zinc protoporphyrin IX is a normal metabolite that is formed in trace amounts during haem biosynthesis. However, in iron deficiency or in impaired iron utilization, zinc becomes an alternative substrate for ferrochelatase and elevated levels of zinc protoporphyrin IX, which has a known low affinity for oxygen, are formed. This zinc-for-iron substitution is one of the first biochemical responses to iron depletion, and erythrocyte zinc protoporphyrin is therefore a very sensitive index of bone-marrow iron status (Labbe et ah, 1999). In addition, zinc protoporphyrin may regulate haem catabolism by acting as a competitive inhibitor of haem oxygenase, the key enzyme of the haem degradation pathway. However, it has been reported... [Pg.332]


See other pages where INDEX elevation is mentioned: [Pg.101]    [Pg.54]    [Pg.101]    [Pg.54]    [Pg.175]    [Pg.330]    [Pg.264]    [Pg.447]    [Pg.300]    [Pg.42]    [Pg.261]    [Pg.323]    [Pg.345]    [Pg.323]    [Pg.324]    [Pg.434]    [Pg.1531]    [Pg.209]    [Pg.309]    [Pg.159]    [Pg.53]    [Pg.286]    [Pg.316]    [Pg.322]    [Pg.324]    [Pg.471]    [Pg.294]    [Pg.138]    [Pg.325]    [Pg.241]    [Pg.296]    [Pg.48]    [Pg.62]    [Pg.310]   
See also in sourсe #XX -- [ Pg.344 ]




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INDEX elevated temperatures

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