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991.
The purpose of this study was to establish an ergonomic basis for the integration of female personnel at military workplaces. The results of anthropometrical and physiological measurements of 1337 male and female subjects (aged 18-25 years) are presented. The empirical design included classical and functional body measures of high ergonomic relevance. Additionally, the isometric forearm-flexor and knee-extensor forces of the subjects were tested as representative variables for their physiological suitability. With regard to biometric and strength parameters, the present results clearly show only small overlaps between the sexes. Rating the 5th percentile of the male subjects as an exclusion value, the anthropometrical variables (sitting and standing body height measures, shoulder breadth, hand length and breadth etc.) show that 29% up to 72% of the women do not match this criterion. The situation becomes even worse when strength parameters are taken into consideration: Only 26% (knee extensors) respectively 3% (forearm flexors) of the females generate higher forces than the corresponding 5th percentiles of their male counterparts. The application of the database established in this survey aims at the integration of female personnel at all kinds of military workplaces; our data account for a combination of anthropometrical and physiological variables. In contrast to former systems based on isolated percentile tables, the results of our investigation make multivariate queries possible in optimization processes. This type of combined database is to be considered a useful tool for the evaluation of workplaces and personal equipment, for general ergonomic considerations and for personnel planning purposes to prevent applicants from occupational harm. 相似文献
992.
The mechanisms of regulation of autophagy are still obscure. In mammalian liver, starvation-induced autophagic proteolysis is regulated by the cellular hydration state in a microtubule- and p38(MAPK)-dependent way. Recent work shows that in yeast, loss of Hog1, the yeast orthologue of p38(MAPK), leads to osmosensitivity of starvation-induced autophagy (Prick et al., Biochem J 2006; 394:153-161), pointing to an evolutionarily conserved mechanism. In this addendum further experiments from hog1Delta yeast cells are shown, which support the hypothesis that starvation- and rapamycin-induced autophagy processes differ in their susceptibility to osmotic stress. The potential mechanisms are discussed. 相似文献
993.
Bicyclo[3.3.1]nonylidenebicyclo[3.3.1]nonane (1) and adamantylideneadamantane (Ad=Ad) are two caged olefins with closely related structures at the double bond. Both compounds react instantaneously with Br2 in chlorinated hydrocarbon solvents to give mixtures of olefin-Br2 aggregates identified as the 1:1 pi-complex and bromonium tribromide, bromonium pentabromide ion pairs. The stoichiometry, formation constants and the electronic spectra of all the species present at equilibrium (pi-complex and bromonium ions), obtained by addition of bromine to alkene 1, have been determined in 1,2-dichloroethane at 25 degrees C and compared with the values that characterize the corresponding aggregates arising from Ad=Ad. The absence of the two bridging CH2 groups in 1 significantly affects all the formation constants. Moreover, at variance with Ad=Ad, olefin 1 reacts with bromine to give, depending on reagent concentration, a substitution product. DFT (B3LYP) and ONIOM computations of 1:1 Br2-olefin complexes for 1 and Ad=Ad confirm that the association energy is larger for the complex 1-Br2. The higher stability of this species seems to be correlated to the greater IP of 1 with respect to Ad=Ad which is able to compensate the reduced polarizability. The experimental value of the formation constant found for the complex 1-Br2, 643 vs 289 M(-1) further supports the primary role exerted by dispersion interactions in alkene-Br2 pi-complexes. 相似文献
994.
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996.
At the dawn of a new era in label‐free quantitation on high‐resolution MS instruments, classical methods such as iTRAQ continue to provide very useful insights in comparative proteomics. The potential to multiplex samples makes this reporter‐based labeling technique highly suited for method optimization as demonstrated here by a set of standard series. Instead of studying ratios of annotated proteins, we propose an alternative method, based on the analysis of the average reporter ratios of all the spectra from a sample or a large distinct subset herein. This strategy circumvents the bias, associated with the annotation and iTRAQ quantitation, leading to increased adequacy in measuring yield differences between workflows. As gel electrophoresis prior to MS analysis is highly beneficial, for example, as a fractionation step, the approach was applied to evaluate the influence of several parameters of the established in‐gel digestion protocol. We quantified the negative effect of SYPRO Ruby staining and the positive effect of gel fixation prior to digestion on peptide yield. Finally, we emphasize the benefits of adding CaCl2 and ACN to a tryptic in‐gel digest, resulting in an up to tenfold enhanced peptide recovery and fewer trypsin missed cleavages. 相似文献
997.
Frère F Schubert WD Stauffer F Frankenberg N Neier R Jahn D Heinz DW 《Journal of molecular biology》2002,317(2):237-247
The seeds of jack fruit (Artocarpus integrifolia) contain two tetrameric lectins, jacalin and artocarpin. Jacalin was the first lectin found to exhibit the beta-prism I fold, which is characteristic of the Moraceae plant lectin family. Jacalin contains two polypeptide chains produced by a post-translational proteolysis which has been shown to be crucial for generating its specificity for galactose. Artocarpin is a single chain protein with considerable sequence similarity with jacalin. It, however, exhibits many properties different from those of jacalin. In particular, it is specific to mannose. The structures of two crystal forms, form I and form II, of the native lectin have been determined at 2.4 and 2.5 A resolution, respectively. The structure of the lectin complexed with methyl-alpha-mannose, has also been determined at 2.9 A resolution. The structure is similar to jacalin, although differences exist in details. The crystal structures and detailed modelling studies indicate that the following differences between the carbohydrate binding sites of artocarpin and jacalin are responsible for the difference in the specificities of the two lectins. Firstly, artocarpin does not contain, unlike jacalin, an N terminus generated by post-translational proteolysis. Secondly, there is no aromatic residue in the binding site of artocarpin whereas there are four in that of jacalin. A comparison with similar lectins of known structures or sequences, suggests that, in general, stacking interactions with aromatic residues are important for the binding of galactose while such interactions are usually absent in the carbohydrate binding sites of mannose-specific lectins with the beta-prism I fold. 相似文献
998.
The distribution of l-malate, sinapic acid esters and 1-sinapoylglucose: l-malate sinapoyltransferase (SMT) which catalyzes the synthesis of sinapoyl-l-malate were examined in preparations of protoplasts obtained from cotyledons of red radish (Raphanus sativus L. var. sativus). Vacuoles isolated from the protoplasts contained all of the SMT activity, all of the accumulated sinapic acid esters and about 50% of free l-malate present initially in the protoplasts. An esterase activity, acting on 1-sinapoyglucose, was found to be exclusively localized in the cytoplasm and a large proportion was found to be recoverable in a 100 000-g pellet obtained from protoplast lysates. The vacuoles were obtained after lysis of the protoplasts by osmotic shock and purification on a Ficoll gradient. The cytoplasmic contamination of vacuole preparations was found to be about 10%, as judged by enzymatic markers and microscopic inspection. No SMT activity was found in a 100 000-g pellet obtained from vacuole lysates. The results indicate that biosynthesis of sinapoyl-l-malate takes place within the central vacuoles of redradish cotyledons.Abbreviation SMT
1-sinapoylglucose: l-malate sinapol-transferase 相似文献
999.
Pedarzani P D'hoedt D Doorty KB Wadsworth JD Joseph JS Jeyaseelan K Kini RM Gadre SV Sapatnekar SM Stocker M Strong PN 《The Journal of biological chemistry》2002,277(48):46101-46109
The biophysical properties of small conductance Ca(2+)-activated K(+) (SK) channels are well suited to underlie afterhyperpolarizations (AHPs) shaping the firing patterns of a conspicuous number of central and peripheral neurons. We have identified a new scorpion toxin (tamapin) that binds to SK channels with high affinity and inhibits SK channel-mediated currents in pyramidal neurons of the hippocampus as well as in cell lines expressing distinct SK channel subunits. This toxin distinguished between the SK channels underlying the apamin-sensitive I(AHP) and the Ca(2+)-activated K(+) channels mediating the slow I(AHP) (sI(AHP)) in hippocampal neurons. Compared with related scorpion toxins, tamapin displayed a unique, remarkable selectivity for SK2 versus SK1 ( approximately 1750-fold) and SK3 ( approximately 70-fold) channels and is the most potent SK2 channel blocker characterized so far (IC(50) for SK2 channels = 24 pm). Tamapin will facilitate the characterization of the subunit composition of native SK channels and help determine their involvement in electrical and biochemical signaling. 相似文献
1000.
Lepez T Vandewoestyne M Hussain S Van Nieuwerburgh F Poppe K Velkeniers B Kaufman JM Deforce D 《PloS one》2011,6(12):e29646