Lehmann effect

A. Dequidt and P. Oswald, Does the electric Lehmann effect exist in cholesteric hquid crystals Eur. Phys. J. E 24(2), 157-166, (2007). 

Phase winding in cholesterics was first observed by Otto Lehmann, the physicist father of liquid crystals, and is known as the Lehmann effect. Brand and Plainer [3] were the first to account for the Lehmann effect with a straightforward symmetry argument that can be used to extract a Lehmann coefficient [2]. 

H.R. Brand and H. Pleiner, New theoretical results for the Lehmann effect in cholesteric liquid crystals, Phys. Rev. A37, R2736 (1988). 

P. Lehmann, R. Moreau, D. Camel, R. Bolcato. A simple analysis of the effect of convection on the structure of the mushy zone in the case of horizontal Bridgman solidification. Comparison with experimental results. J Cryst Growth 183 690, 1998. 

The physiological effects of the fluoride ion were reviewed by McClure 74) in 1933. Lehmann 72) published an article on the toxicity of aromatic fluorine compounds in 1928. However, it has been impossible to investigate the toxicity of the organofluorine compounds as thoroughly as that of the organochlorine compounds. 

In 1888, Walter studied the quenching of fluorescence, by the concentration effect, of fluorescein solutions. Nicols and Merrit observed in 1907, in solutions of eosine and resoruflne, the symmetry existing between their absorption and fluorescence spectra. In 1910, Ley and Engelhardt determined the fluorescence quantum yield of various benzene derivatives, values that were still referred to until recent years [18], The works by Lehmann and Wood, around 1910, marked the beginning of analysis based on fluorescence [4],... 

Some studies found kava to be effective using only 2 acute doses (preoperatively), while others found benefit after chronic doses (Bhate et al. 1989 Lehmann et al. 1989 Volz and Kieser 1997). Another interesting study found kavain to be equivalent in efficacy to the benzodiazepine oxazepam on standard measures of anxiety (Anxiety Status Inventoiy and Zung s Self-Rating Anxiety Scale) (Lindenberg and Pitule-Schodel 1990). There were no serious side effects reported in the clinical studies reviewed by Pittler and Ernst (2000). 

Evidence of central nervous system toxicity in animals includes disturbed equilibrium in cats exposed to 7,200 ppm chloroform for 5 minutes, deep narcosis in cats exposed to 21,500 ppm for 13 minutes, deep narcosis in mice exposed to 4,000 ppm for 30 minutes, slight narcosis in mice exposed to 3,100 ppm for 1 hour, and no obvious effects in mice exposed to 2,500 ppm for 2 hours (Lehmann and Flury 1943). Memory retrieval was affected in mice exposed to chloroform via anesthesia (concentration not specified) (Valzelli et al. 1988). The amnesic effect was not long-lasting. 

Inhalation exposure to high chloroform concentrations induced narcosis (Lehmann and Flury 1943 Sax 1979) and reversible impairment of memory retrieval in animals. High, single, oral doses of chloroform caused ataxia, incoordination, anesthesia, and brain hemorrhage in mice (Balster and Borzelleca 1982 Bowman et al. 1978). Behavioral effects were observed at lower oral doses. 

Although this procedure offers no advantage over that of Hiinig, Lehmann, and Grimmer, it effectively illustrates a new method for the synthesis of symmetrical and unsymmetrical carbodiimides. The generality of this procedure is limited only by the number of substituted benzohydroxamoyl chlorides that can be made without difficulty, as a variety of N-sulfinylamines is easily accessible. ... 

Petri S, Dueck A, Lehmann G et al (2011) Increased siRNA duplex stability correlates with reduced off-target and elevated on-target effects. RNA 17 737-749... 

Transferrin plays a major role in the transport and cellular uptake of thorium (Peter and Lehmann 1981). Thorium can be displaced from transferrin by an excess of iron, but it is not known whether thorium and iron bind to the same sites on the transferrin molecule. It has also been determined that thorotrast (Th02 colloid) blocks the uptake of labelled protein by the RES in female rabbits and in both male and female rats (Hyman and Paldino 1967). The mechanism of the blockade is not clear. Sex differences were found in rabbits but not in rats. The particle size of the Thorotrast colloid influences its effect on the uptake of protein only particles larger than 1 pm will interfere with uptake of protein by the RES. 

AP5 and CPP are antagonists having a binding affinity for the NMDA receptor comparable to glutamate (Lehmann et al., 1987 Murphy et al., 1987). Spinally administered, both compounds exert antinociceptive effects (Coderre et al., 1994 Goettl et al., 1994 Kristensen et al., 1994 Leem et al., 1996). The limitation of such structures is of course their low lipophilicity which restricts their availability mainly to the periphery and usually requires spinal administration to obtain therapeutic efficacy. 

Attempts by 0. E. Brown-Sequard and A. d Arsonval, and S. Merkel have been made to show that the depressed feeling and uneasiness experienced in crowded rooms is not solely due to the diminution of oxygen, and increase of carbon dioxide, but is rather due to the presence of a volatile organic poison in the expired air. This hypothesis was contested by A. Dastre and P. Loye, A. Russo-Giliberti and G. Alessi, D. H. Bergey, S. W. Mitchell and J. S. Billings, G. von Hofmann-Wellenhof, and K. B. Lehmann and F. Jessen. 0. Wurster, and T. Cramer attributed the injurious effects to the presence of nitrates. 

Fernandez LA, Lehmann R, Luzi L, Battezzati A, Angelico MC, Ricordi C, Tzakis A, Alejandro R. The effects of maintenance doses of FK506 versus cyclosporin A on glucose and lipid metabolism after orthotopic liver transplantation. Transplantation 1999 68(10) 1532-41. 

Fig. 51 Examples of T-shaped bolaamphiphiles with non-polar lateral RF/RH-chains showing the effect of fluorination on mesophase types and transition temperatures (77° C) [316-318, Lehmann A, Prehm M, Tschierske C, unpublished results, 319]...

Taubert D, Roesen R, Lehmann C, Jung N, Schomig E. 2007. Effects of low habitual cocoa intake on blood pressure and bioactive nitric oxide a randomized controlled trial. JAMA 298 49-60. 

Mayer A. M. S., Hall M., Fay M. J., Lamar P, Pearson C., Prozialeck W. C., Lehmann V. K. B., Jacobson P. B., Romanic A. M., Uz T., and Manev H. (2001). Effect of a short-term in vitro exposure to the marine toxin domoic acid on viability, tumor necrosis factor-alpha, matrix metalloproteinase-9 and superoxide anion release by rat neonatal microglia. BMC Pharmacol. 1 7. 

Borbely AA, Baumann F, Brandeis D, Strauch I, Lehmann D. Sleep deprivation effect on sleep stages and EEG power density in man. Electroencephalogr Clin Neurophysiol 1981 51 483-495. 

The use of centrifugation to separate the liquid from solid phases in traditional batch or tube techniques has several disadvantages. Centrifugation could create electrokinetic effects close to soil constituent surfaces that would alter the ion distribution (van Olphen, 1977). Additionally, unless filtration is used, centrifugation may require up to 5 min to separate the solid from the liquid phases. Many reactions on soil constituents are complete by this time or less (Harter and Lehmann, 1983 Jardine and Sparks, 1984 Sparks, 1985). For example, many ion exchange reactions on organic matter and clay minerals are complete after a few minutes, or even seconds (Sparks, 1986). Moreover, some reactions involving metal adsorption on oxides are too rapid to be observed with any batch or, for that matter, flow technique. For these reactions, one must employ one of the rapid kinetic techniques discussed in Chapter 4. 

D12. Dwenger, A., Funck, M., Lueken, B., Schweitzer, G., and Lehmann, U., Effect of ascorbic acid on neutrophil functions and hypoxanthine-xanthine oxidase-generated, oxygen derived radicals. Eur. J. Clin. Chem. Clin. Biochem. 30, 187-191 (1992). 

Bottino, R., Fernandez, L. A., Ricordi, C., Lehmann, R., Tsan, M. F., Oliver, R. and Inverardi, L. (1998). Transplantation of allogeneic islets of Langer-hans in the rat liver Effects of macrophage depletion on graft survival and microenvironment activation. Diabetes 47, 316-323. 

Christofferson RD, Lehmann KG, Martin GV et al. Effect of chronic total coronary occlusion on treatment strategy. Am J Cardiol 2005 95 1088-1091. 

Roth B, Herkenrath P, Lehmann H-J, et al. 1988. Di-(2-ethylhexyl)-phthalate as plasticizer in PVC respiratory tubing systems Indications of hazardous effects on pulmonary function in mechanically ventilated, preterm infants. Eur J Pediatr 147 41-46. 

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