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101.
Erik Berg Schmidt Jeppe Hagstrup Christensen Inge Aardestrup Trine Madsen Sam Riahi Vibeke Ellegaard Hansen Helle Aarup Skou 《Lipids》2001,36(1):S65-S68
There is some evidence from epidemiology that intake of n-3 polyunsaturated fatty acids (PUFA) from seafood may protect against coronary artery disease (CAD). This hypothesis is further supported from animal data showing a beneficial effect of n-3 PUFA on thrombosis and atherosclerosis in animals fed fish oils in most, but not all, studies. There are several mechanisms by which an increased intake of marine n-3 PUFA may protect against CAD; the most universal finding is a reduction of plasma triglycerides. It is puzzling, however, that a very low amount of n-3 PUFA, with no known beneficial biochemical effects, seems to be cardioprotective. It has therefore been of paramount interest to perform clinical trials. Such evidence and trials are discussed in later chapters, and the results have been very encouraging. 相似文献
102.
Autogenous deformation and RH-change in perspective 总被引:12,自引:0,他引:12
Autogenous deformation and change of the relative humidity (RH-change) have been described and registered for a century. However, it is only within the last decade that these phenomena have received appreciable attention. The reason for this is that autogenous deformation and autogenous RH-change are phenomena of special importance within high-strength (high-performance) concrete technology, and a significant utilisation of these concretes did not take place until the early 1980s. In the present paper an historical overview of autogenous deformation and RH-change is given. In addition, due to the present status of this research field both terminology and measuring techniques are described in detail. Finally, some expectations for future research in this field are given. 相似文献
103.
104.
105.
Molecular Heterojunctions of Oligo(phenylene ethynylene)s with Linear to Cruciform Framework
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Zhongming Wei Tim Hansen Marco Santella Xintai Wang Christian R. Parker Xingbin Jiang Tao Li Magni Glyvradal Karsten Jennum Emil Glibstrup Nicolas Bovet Xiaowei Wang Wenping Hu Gemma C. Solomon Mogens Brøndsted Nielsen Xiaohui Qiu Thomas Bjørnholm Kasper Nørgaard Bo W. Laursen 《Advanced functional materials》2015,25(11):1700-1708
Electrical transport properties of molecular junctions are fundamentally affected by the energy alignment between molecular frontier orbitals (highest occupied molecular orbital (HOMO) or lowest unoccupied molecular orbital (LUMO)) and Fermi level (or work function) of electrode metals. Dithiafulvene (DTF) is used as substituent group to the oligo(phenylene ethynylene) (OPE) molecular wires and different molecular structures based on OPE3 backbone (with linear to cruciform framework) are achieved, with viable molecular orbitals and HOMO–LUMO energy gaps. OPE3, OPE3–DTF, and OPE3–tetrathiafulvalene (TTF) can form good self‐assembled monolayers (SAMs) on Au substrates. Molecular heterojunctions based on these SAMs are investigated using conducting probe–atomic force microscopy with different tips (Ag, Au, and Pt) and Fermi levels. The calibrated conductance values follow the sequence OPE3–TTF > OPE3–DTF > OPE3 irrespective of the tip metal. Rectification properties (or diode behavior) are observed in case of the Ag tip for which the work function is furthest from the HOMO levels of the OPE3s. Quantum chemical calculations of the transmission qualitatively agree with the experimental data and reproduce the substituent effect of DTF. Zero‐bias conductance, and symmetric or asymmetric couplings to the electrodes are investigated. The results indicate that improved fidelity of molecular transport measurements may be achieved by systematic studies of homologues series of molecular wires applying several different metal electrodes. 相似文献
106.
107.
Kacper Januchta Pengfei Liu Søren R. Hansen Theany To Morten M. Smedskjaer 《Journal of the American Ceramic Society》2020,103(3):1656-1665
Developing less brittle oxide glasses is a grand challenge in the field of glass science and technology, as it would pave the way toward new glass applications and limit the overall raw material usage and energy consumption. However, in order to achieve this goal, more insight into the correlation between the chemical composition and material properties is required. In this work, we focus on the mechanical properties of quaternary sodium aluminoborosilicate glasses, wherein systematic changes in glass chemistry yield different resistances to indentation crack initiation. We discuss the origin of the composition dependence of indentation cracking based on an evaluation of the deformation mechanism taking place during the indentation event. To this end, we use a simple metric, the extent of indent side length recovery upon annealing, to quantify the extent of reversible volume deformation. Finally, we also compare the compositional trend in crack initiation resistance to that in crack growth resistance (fracture toughness), showing no simple correlation among the two. 相似文献
108.
A.M. Zolini W.G. Ortiz E. Estrada-Cortes M.S. Ortega S. Dikmen F. Sosa J.O. Giordano P.J. Hansen 《Journal of dairy science》2019,102(1):846-856
Fertility-promoting effects of treatment of lactating dairy cattle with human chorionic gonadotropin (hCG) after artificial insemination (AI) have been variable. Here, we tested whether fertility response to hCG in lactating Holstein cows interacts with genotype and parity. Primiparous (n = 538) and multiparous (n = 613) cows were treated with hCG (3,300 IU) or vehicle 5 d after AI. Pregnancy was diagnosed on d 32 and 60 after AI. A subset of cows (n = 593–701) was genotyped for 4 single nucleotide polymorphisms (SNP) previously associated with fertility. Treatment with hCG increased progesterone concentration on d 12 after AI regardless of genotype or parity. Pregnancy per AI was improved by hCG in primiparous cows but not in multiparous cows. Moreover, hCG treatment interacted with a SNP in coenzyme Q9 (COQ9) to affect fertility. Fertility of cows treated with vehicle was greatest for the AA allele, whereas fertility was lowest for the same genotype among cows treated with hCG. Pregnancy per AI was also affected by genotype for heat shock protein A1-like (HSPA1L) and progesterone receptor (PGR), but no interactions were observed with treatment. Genotype for a SNP in prostate androgen-regulated mucin-like protein 1 (PARM1) was not associated with fertility. Overall, results show that variation in response to hCG treatment on fertility depends on parity and interacts with a SNP in COQ9. 相似文献
109.
H. U. Kibbel J. Teller P. Hansen A. Reiter 《Advanced Synthesis \u0026amp; Catalysis》1980,322(5):769-784
Reactions of 3-Aroylimino-3H-1,2-dithioles The thiolates 3 and 10 prepared from 3-aroylimino-4-aroylthio-5-cyano-3H-1,2-dithioles 1 with bases, react with alkylhalides and acylhalides to the corresponding 4-S-substituted compounds 6, 11 and 7 , respectively. Treatment of the thiolates with 1-chloropropanone gives the bicyclic compound 12 by intramolecular cyclization involving the 5-cyano-group. 3,6-Bis-(acylimino)-3H,6H-[4,3-c] [1,2]-dithioles 2 or 8 are prepared from the S-acylated dithioles 1 or 7 and sulphur in pyridine/benzene. 1,2,4-Triazines 13 are formed by the reaction of dithiol es 1 orthiolates 3 with phenylhydrazine. The thiolates give upon protonation the mesoionic dithioliumthiolates 4 . Coordination compounds are obtained from the reaction of the thiolates with cations of 3d-elements. On the basis of the chemical behaviour of the new 3-acylimino-1,2-dithioles and the results of spectroscopic measurements a strong bonding interaction between the N-acyl-carbonylgroup and the dithiole ring system in these compounds is supposed. 相似文献
110.
Hanne Boskov Hansen Claus V Rasmussen Knud Erik Bach Knudsen se Hansen 《Journal of the science of food and agriculture》2003,83(1):76-85
The aim of this study was to measure the variation in dietary fibre (DF) content and composition among different rye varieties grown in the same location in three successive years and to estimate the contributions of genotype and harvest year to this variation. The study included grain from 19 different varieties of rye, of which seven varieties were analysed in all three years. The content of total DF in all samples ranged from 147 to 209 g kg?1 dry matter (dm), with 34–66 g kg?1 being water‐extractable (WE) DF and 108–159 g kg?1 being water‐unextractable (WUE) DF. The main DF component was arabinoxylan (AX) with a content of 80–121 g kg?1 dm, of which 26–41 g kg?1 dm was WE AX. The ratio of arabinose to xylose (ara/xyl) of total AX ranged from 0.59 to 0.69. The content of β‐glucan was 13–22 g kg?1 dm and that of fructan was 45–64 g kg?1 dm. Analysis of the data from seven varieties and three harvest years showed a highly significant influence of harvest year on most DF components. Significant genotype effects were found for the contents of total DF, total AX, β‐glucan and fructan and for the ara/xyl ratio of total and WUE AX. Estimation of variance components showed that yearly variations in the contents of total DF, total AX, WUE DF, WUE AX and β‐glucan were generally higher (27–55% of total variance) than genotype effects (14–19%). The ara/xyl ratio of total and WUE AX showed a high influence of genotype (46 and 43% respectively). Non‐adapted rye varieties with small kernel size had the highest contents of total DF and total AX. The content of β‐glucan was positively correlated with kernel weight (r = 0.68), whereas no overall correlation was found between kernel size and the content of DF. As a conclusion, the variation in DF content and composition in this study was significantly influenced by both harvest year and rye genotype. © 2002 Society of Chemical Industry 相似文献