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61.
62.
Bakker Julie; Brand Teus; Van Ophemert Jan; Slob A. Koos 《Canadian Metallurgical Quarterly》1993,107(3):480
Male rats, neonatally treated with ATD (1,4,6-androstatriene-3,17-dione), which blocks the aromatization of testosterone into estradiol (E?), were tested for adult partner preference behavior (PPB; estrous female vs active male). Castration caused a decrease in preference for the female partner in all males, with ATD males showing lower preference for the female partner than controls. Long-term castrated males did not show preference for either partner. Precastration levels of PPB in control males occurred after treatment with E? or dihydrotestosterone (DHT) plus E?. DHT alone had no effect on PPB. With E? alone, the ATD males clearly preferred the male partner. When DHT was added, these ATD males showed no preference for either partner or a low preference for the female partner. In conclusion, adult PPB in male rats is activated by endogenous testosterone or by both its metabolites (DHT and E?) or by E? alone. ATD males showed a much lower preference for the female. There was a differential effect of DHT and E?: DHT had no effect, but E? clearly caused ATD to prefer the male partner and control males to prefer the female partner. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
This paper explores whether principles obtained for the packing of solid macroscopic particles can be applied to the study of excess volumes of liquid mixtures. The approach is applied to mixtures of ‘pure’ hydrocarbons, i.e. containing only C- and H-atoms. In this new approach a set of equations was developed for the estimation of excess volumes of liquid hydrocarbon mixtures, which works better for mixtures of linear and cyclic hydrocarbons than existing estimation methods. An advantage of the new approach is that it reveals differences between mixtures of molecules with different steric characteristics, and shows that steric effects related to molecular shape and rigidity are necessary components of a fundamental understanding of liquid mixtures. 相似文献
64.
Roel Bosma Uzay Kaymak Jan van den Berg Henk Udo Johan Verreth 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2011,15(2):295-310
To reveal farmers?? motives for on-farm diversification and integration of farming components in the Mekong Delta, Vietnam, we developed a fuzzy logic model (FLM) using a 10-step approach. Farmers?? decision-making was mimicked in a three-layer hierarchical architecture of fuzzy inference systems, using data of 72 farms. The model includes three variables for family motives of diversification, six variables related to component integration, next to variables for the production factors and for farmers?? appreciation of market prices and know-how on 10 components. To obtain a good classification rate of the less frequent activities, additional individual fine-tuning was necessary after general model calibration. To obtain the desired degree of sensitivity to each variable, it was necessary to use up to five linguistic values for some of the input and output variables in the intermediate hierarchical layers. Model??s sensitivity to motivational variables determining diversification and integration was of the same magnitude as its sensitivity to market prices and farmers?? know-how of the activities, but less than its sensitivity to labour, capital and land endowment. Modelling to support strategic decision-making seems too elaborate for individual farms, but FLM will be useful to integrate farmers?? opinions in strategic decision-making at higher hierarchical levels. 相似文献
65.
J. K. Weil R. E. Koos W. M. Linfield N. Parris 《Journal of the American Oil Chemists' Society》1979,56(9):873-877
Purified polyglycol ester and ether types of non-ionic surfactants were investigated to determine optimum structures for wetting hydrophobic soils, peat moss, and standard cotton skeins (Draves test). The most rapid wetting of hydrophobic soil was observed with diethylene glycol monoesters of fatty acids possessing 8,9, and 10 carbon atoms and triethylene glycol monoesters of fatty acids containing 9 and 10 carbon atoms. Methyl pentaethylene glycol decanoate and methyl hexaethylene glycol dodecanoate were also effective wetting agents for hydrophobic soil. Nonionics with slightly longer oxy-alkylene chains most effectively wet Draves skeins and peat moss. Diethylene glycol and triethylene glycol monodecyl ethers also effectively wet hydrophobic soil and peat moss. 相似文献
66.
Xinxin?Guo Dane?BicanicEmail author Koos?Keijser Robert?Imhof 《European Food Research and Technology》2003,217(3):273-276
The concept of optothermal transient emission radiometry at a wavelength of 2.94 µm was applied to non-destructively determine the level of hydration and the profile of hydration in the skin of intact fresh grapes taken from top and bottom sections of the same bunch. 相似文献
67.
Kindt JH Thurner PJ Lauer ME Bosma BL Schitter G Fantner GE Izumi M Weaver JC Morse DE Hansma PK 《Nanotechnology》2007,18(13):135102
The topography of freshly fractured bovine and human bone surfaces was determined by the use of atomic force microscopy (AFM). Fracture surfaces from both kinds of samples exhibited complex landscapes formed by hydroxyapatite mineral platelets with lateral dimensions ranging from ~90?nm × 60?nm to ~20?nm × 20?nm. Novel AFM techniques were used to study these fracture surfaces during various chemical treatments. Significant topographical changes were observed following exposure to aqueous solutions of ethylenediaminetetraacetic acid (EDTA) or highly concentrated sodium fluoride (NaF). Both treatments resulted in the apparent loss of the hydroxyapatite mineral platelets on a timescale of a few seconds. Collagen fibrils situated beneath the overlying mineral platelets were clearly exposed and could be resolved with high spatial resolution in the acquired AFM images. Time-dependent mass loss experiments revealed that the applied agents (NaF or EDTA) had very different resulting effects. Despite the fact that the two treatments exhibited nearly identical results following examination by AFM, bulk bone samples treated with EDTA exhibited a ~70% mass loss after 72?h, whereas for the NaF-treated samples, the mass loss was only of the order of ~10%. These results support those obtained from previous mechanical testing experiments, suggesting that enhanced formation of superficial fluoroapatite dramatically weakens the protein-hydroxyapatite interfaces. Additionally, we discovered that treatment with aqueous solutions of NaF resulted in the effective extraction of noncollagenous proteins from bone powder. 相似文献
68.
M. Lonyuk M. Bosma C.A.M. Vijverberg A. Bakker M. Janssen 《Progress in Organic Coatings》2008,61(2-4):308-315
This work addresses the correlation between stone-chip resistance and mechanical properties of automotive solid colour coating systems. Single-impact tests, which are believed to realistically simulate chipping due to stone impact, were performed to investigate eight different coating systems. Additionally, conventional tests on chip resistance currently used in automotive industry were performed. Results were related to mechanical properties of the coatings, measured by dynamic mechanical thermal analysis and double cantilever adhesion test. It is found that coating systems with a low glass transition temperature for the primer have better stone-chip resistance. 相似文献
69.
Reliable and lightning‐safe monitoring of wind turbine rotor blades using optically powered sensors 下载免费PDF全文
K. Worms C. Klamouris F. Wegh L. Meder D. Volkmer S. P. Philipps S. K. Reichmuth H. Helmers A. Kunadt J. Vourvoulakis A. W. Bett C. Koos W. Freude J. Leuthold W. Stork 《风能》2017,20(2):345-360
Blade condition monitoring systems with fiber‐optic sensors attract much attention because they are resistant to lightning strikes, a major issue with increasing blade lengths. However, fiber‐optic sensor systems are more complex and more expensive than their electronic counterparts. We describe a new blade condition monitoring system, which combines the lightning safety of optical fibers with the reliability and cost‐effectiveness of electronic sensors. The optical fibers transport data from the blades to the hub, and in addition, they provide the electrical power for operating the sensor units in the blades. To achieve full protection against lightning‐induced electromagnetic fields, an appropriate shielding of the sensor units is required. We present results on the reliability of a newly developed prototype based on optically powered sensors. In a field trial, the unit monitored successfully the blade vibrations of a 1.5 MW wind turbine for a period of 23 months. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
70.
Zeneng Wang Jennie Hazen Xun Jia Elin Org Yongzhong Zhao Lucas J. Osborn Nisreen Nimer Jennifer Buffa Miranda K. Culley Daniel Krajcik Bert-Jan H. van den Born Koos Zwinderman Bruce S. Levison Max Nieuwdorp Aldons J. Lusis Joseph A. DiDonato Stanley L. Hazen 《International journal of molecular sciences》2021,22(24)
L-alpha glycerylphosphorylcholine (GPC), a nutritional supplement, has been demonstrated to improve neurological function. However, a new study suggests that GPC supplementation increases incident stroke risk thus its potential adverse effects warrant further investigation. Here we show that GPC promotes atherosclerosis in hyperlipidemic Apoe−/− mice. GPC can be metabolized to trimethylamine N-oxide, a pro-atherogenic agent, suggesting a potential molecular mechanism underlying the observed atherosclerosis progression. GPC supplementation shifted the gut microbial community structure, characterized by increased abundance of Parabacteroides, Ruminococcus, and Bacteroides and decreased abundance of Akkermansia, Lactobacillus, and Roseburia, as determined by 16S rRNA gene sequencing. These data are consistent with a reduction in fecal and cecal short chain fatty acids in GPC-fed mice. Additionally, we found that GPC supplementation led to an increased relative abundance of choline trimethylamine lyase (cutC)-encoding bacteria via qPCR. Interrogation of host inflammatory signaling showed that GPC supplementation increased expression of the proinflammatory effectors CXCL13 and TIMP-1 and activated NF-κB and MAPK signaling pathways in human coronary artery endothelial cells. Finally, targeted and untargeted metabolomic analysis of murine plasma revealed additional metabolites associated with GPC supplementation and atherosclerosis. In summary, our results show GPC promotes atherosclerosis through multiple mechanisms and that caution should be applied when using GPC as a nutritional supplement. 相似文献