Quantitative analysis of acetaldehyde in whole blood from human and various animals by gas chromatography

Acetaldehyde present in the blood of bull, chicken, hamster, horse, human, monkey, pig, rabbit, rat and sheep, was quantitatively analyzed by a newly developed gas chromatographic method. Acetaldehyde in a blood sample was reacted with cysteamine to give 2-methylthiazolidine, which was extracted with dichloromethane and subsequently analyzed by gas chromatography with a fused-silica capillary column and a nitrogen-phosphorus detector. The quantities of acetaldehyde found in blood ranged from 2.04 micromol/ml (hamster) to 14.8 micromol/ml (pig). The quantity of acetaldehyde recovered from human blood was 6.17 micromol/ml.     

Measurement of stress relaxation in broken fibers embedded in epoxy using Raman spectroscopy

Raman spectroscopy was used to study the stress relaxation in broken fibers in a unidirectional composite. A single-fiber model composite consisting of a high modulus PAN-based carbon fiber and an epoxy resin matrix was loaded incrementally until the fiber got broken.Then the stress profile in the broken fiber was monitored under constant overall strain for 1000 hours by determining fiber stress through the stress dependence of the 2700 cm–1 Raman band peak position. Three experiments were done at different overall strains.It was observed that the stress profile in each broken fiber changed only a little even after 1000 hours whereas matrix normal stress in the fiber direction relaxed to about a quarter of the initial value in about 200 hours. It is shown that this result does not support linear viscoelastic solutions based on perfect bonding at interface since the present experiments had interfacial debonding and matrix shear yielding around fiber breaks.     

Immobilized liposome chromatography for studies of protein-membrane interactions and refolding of denatured bovine carbonic anhydrase

Seasonal variations of pesticide residues in surface waters and ground waters of the Imathia area of Central Mecedonia (N. Greece) were determined for the period from May 1996 to April 1997. The sampling cruises included eight sites in rivers Aliakmon, Loudias, Tripotamos, Arapitsa and Canal-66, seven water springs in the mountain Vermion, seven rainfall water collection stations and one hundred underground points. Solid-phase extraction disks followed by gas chromatographic techniques with flame thermionic detection, electron capture detection and mass-selective detection were used for the monitoring of various pesticides their transformation products in environmental waters. The most commonly encountered pesticides in underground waters, were alachlor, atrazine, desethylatrazine (DEA), metolachlor, molinate, propanil, simazine, carbofuran, diazinon and parathion methyl. The above compounds including propazine, trifluralin, malathion, parathion ethyl, lindane, alpha-benzene hexachloride (alpha-BHC), beta-BHC, 4,4'-DDE and heptachlor were determined in river waters. The higher concentrations in underground waters were measured during the period from May to August, 1996, following seasonal application and diminished significantly during the autumn and winter. Water pollution by triazine and chloroacetanilides was highest in the estuarine areas; showing that many of these compounds are transported significant distances from their application sites. The major inputs of atrazine, alachlor, simazine and metolachlor occurred in May and June just after their application. Atrazine, DEA, diazinon and metolachlor were also detected in spring waters at concentration levels below 0.006 microgram/l. Finally, atrazine, DEA, carbofuran, simazine, diazinon, parathion ethyl and parathion methyl were detected in rainfall water samples collected in the agricultural area of Imathia (central part of the plain).     

Application of controlled switching to 500-kV shunt reactor current interruption

To suppress reignition overvoltages caused when a 500-kV shunt reactor current is interrupted by a 550-kV one-break circuit breaker (CB), a study was carried out on controlled switching. Using a full-scale test circuit, reactor current interruption tests were carried out to obtain the relation between opening phase angle and generation of reignition. The results showed that even with the dispersion of CB operations taken into account, there were contact separation points free from high reignition overvoltages. It was also proved that no voltage escalations were caused by reignition and high-frequency arc extinction, and that overvoltages due to current chopping were at a safe level in terms of equipment insulation.     

Individual differences in executive functions are almost entirely genetic in origin.

Recent psychological and neuropsychological research suggests that executive functions--the cognitive control processes that regulate thought and action--are multifaceted and that different types of executive functions are correlated but separable. The present multivariate twin study of 3 executive functions (inhibiting dominant responses, updating working memory representations, and shifting between task sets), measured as latent variables, examined why people vary in these executive control abilities and why these abilities are correlated but separable from a behavioral genetic perspective. Results indicated that executive functions are correlated because they are influenced by a highly heritable (99%) common factor that goes beyond general intelligence or perceptual speed, and they are separable because of additional genetic influences unique to particular executive functions. This combination of general and specific genetic influences places executive functions among the most heritable psychological traits. These results highlight the potential of genetic approaches for uncovering the biological underpinnings of executive functions and suggest a need for examining multiple types of executive functions to distinguish different levels of genetic influences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deeper into attachment and culture.

Replies to comments by 7 authors (see records 2001-18772-008, 2001-18772-009, 2001-18772-010, 2001-18772-011, and 2001-18772-012) in reference to the F. Rothbaum et al's original article (see record 2000-02781-001), which highlighted evidence of cultural variations in, and noted ways in which attachment theory is laden with Western values and meaning in comparisons of the US and Japan. Here, Rothbaum et al defend their central thesis and note areas of their agreement and disagreement with the aforementioned comments and criticisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Glycothermal synthesis of vanadium(III) phosphate hydrates

Glycothermal reaction of various vanadium compounds with triethyl phosphate yielded two hydrate phases of vanadium(III) phosphate having tetragonal (Phase 1) and monoclinic (Phase 2) crystal systems, depending on the reaction conditions such as phosphorus/vanadium ratio, vanadium starting material, reaction temperature and solvent. Thermal treatment of Phase 2 in an anaerobic condition caused transformation to Phase 1 which finally transformed to VPO₄ through an intermediate phase (Phase M). Heat treatment of both the phases in an aerobic condition caused the formation of β-VOPO₄.     

Neurofilament deficiency in quail caused by nonsense mutation in neurofilament-L gene

The existence of a neurofilament-deficient mutant of Japanese quail was recently documented (Yamasaki, H., C. Itakura, and M. Mizutani. 1991. Acta Neuropathol. 82:427-434), but the genetic events leading to the neurofilament deficiency have yet to be determined. Our molecular biological analyses revealed that the expression of neurofilament-L (NF-L) gene was specifically repressed in neurons of this mutant. To search for mutation(s) responsible for the shutdown of this gene expression, we cloned and sequenced the NF-L genes in the wild-type and mutant quails. It is eventually found that the NF-L gene in the mutant includes a nonsense mutation at the deduced amino acid residue 114, indicating that the mutant is incapable of producing even a trace amount of polymerization-competent NF-L protein at any situation. The identification of this nonsense mutation provides us with a solid basis on which molecular mechanisms underlying the alteration in the neuronal cytoskeletal architecture in the mutant should be interpreted.     

The tyrosine kinase regulator Cbl enhances the ubiquitination and degradation of the platelet-derived growth factor receptor alpha

The Cbl protooncogene product has emerged as a negative regulator of receptor and nonreceptor tyrosine kinases. We recently demonstrated that oncogenic Cbl mutants upregulate the endogenous tyrosine kinase signaling machinery when expressed in the NIH 3T3 cells, and identified the platelet-derived growth factor receptor-alpha (PDGFRalpha) as one of the tyrosine kinases targeted by these oncogenes. These findings suggested a role for the normal Cbl protein in negative regulation of the PDGFRalpha. However, the mechanism of such negative regulation remained to be determined. Here we show that overexpression of the wild-type Cbl enhances the ligand-induced ubiquitination of the PDGFRalpha. Concomitantly, the PDGFRalpha in Cbl-overexpressing cells undergoes a faster ligand-induced degradation compared with that in the control cells. These results identify a role for Cbl in the regulation of ligand-induced ubiquitination and degradation of receptor tyrosine kinases and suggest one potential mechanism for evolutionarily conserved negative regulatory influence of Cbl on tyrosine kinases.