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71.
72.
Bioassays conducted with a Y-tube olfactometer provided evidence that both sexes of the cerambycid beetle Megacyllene caryae (Gahan) were attracted to odor produced by males. Odor collected from male M. caryae contained eight male-specific compounds: a 10:1 blend of (2S,3R)- and (2R,3S)-2,3-hexanediols (representing 3.2 ± 1.3% of the total male-specific compounds), (S)-(−)-limonene (3.1 ± 1.7%), 2-phenylethanol (8.0 ± 2.4%), (−)-α-terpineol (10.0 ± 2.8%), nerol (2.1 ± 1.5%), neral (63.3 ± 7.3%),
and geranial (8.8 ± 2.4%). Initial field bioassays determined that none of these compounds was attractive as a single component.
Further field trials that used a subtractive bioassay strategy determined that both sexes were attracted to the complete blend
of synthetic components, but the elimination of any one component resulted in a decline in trap captures. Blends that were
missing (2S,3R)-2,3-hexanediol, (2R,3S)-2,3-hexanediol, or citral (a 1:1 mixture of neral and geranial) attracted no more beetles than did controls. A pheromone
blend of this complexity, composed of alkanediols, terpenoids, and aromatic alcohols, is unprecedented for cerambycid species. 相似文献
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74.
Alonso-Lomillo MA Rüdiger O Maroto-Valiente A Velez M Rodríguez-Ramos I Muñoz FJ Fernández VM De Lacey AL 《Nano letters》2007,7(6):1603-1608
Multiwalled carbon nanotubes grown on gold electrodes manufactured by microtechnology techniques have been used as a platform for oriented and stable immobilization of a Ni-Fe hydrogenase. Microscopic and electrochemical characterization of the system are presented. High-density currents due to H2 oxidation electrocatalysis, stable for over a month under continuous operational conditions, were measured. The functional properties of this nanostructured hydrogenase electrode are suitable for hydrogen biosensing and biofuel applications. 相似文献
75.
A number of acrylate and methacrylate side chain polymers in which the mesogenic moiety is either a 4′-n-pentyl- or 4′-(2-methylbutyl)-biphenyl-4-yl group have been synthesized. A systematic investigation into the effect on the thermal properties of the acrylate polymers containing the n-pentylbiphenylyl moiety, by changing the size of the flexible spacer group, has revealed large differences in the smectic thermal stability of these polymers with respect to whether the flexible spacer group contains an even or odd number of methylene groups. An explanation is given as to why this alternation effect was observed. X-ray diffraction has shown the smectic phase to be SA in type with a near perfect bilayered structure for the polyacrylates, but a more disordered bilayered structure for the methacrylates. Two of the acrylate polymers exhibit a second smectic phase which has not yet been identified. 相似文献
76.
This study evaluates the antioxidant properties and ACE inhibition capacities of eight individual flavonoids before and after incubation with Bifidobacterium animalis ssp. lactisLAFTI@B94®. Changes in flavonoid content and the survival of the probiotics, incubated in individual flavonoid solutions as the only source of carbon, were also determined. The glycosylated flavonoids permitted a higher survival rate of the probiotic bacteria with survival percentages above 50% at 48 h of incubation. The incubation of B. animalis B94 with individual catechins would supposedly produce an increase in all the biological activities tested (ABTS, FRAP and ACE inhibition), but the increments were minor or imperceptible in the flavonol solutions. Epigallocatechin, catechin and epicatechin solutions registered the most important changes in ABTS, FRAP and ACE inhibition capacity, in some cases even doubling their biological activities after incubation with the bacteria. These results are encouraging as the incorporation of B. animalis B94 in various polyphenol-rich foods could be a way of improving the antioxidant properties of the foods. In addition, the polyphenol-rich food could act as a matrix for probiotic strains. 相似文献
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78.
Rebecca Lacey Mai Stafford Amanda Sacker Anne McMunn 《Journal of population ageing》2016,9(1-2):69-89
Studies investigating the impact of combining paid work and family life on wellbeing have generally used information at one or a limited number of points in the life course, and have mainly focused on women. This study uses multi-channel sequence analysis to characterise work-family life courses across adulthood (ages 16–60) for more than 1500 men and women in the MRC National Study of Health and Development. Wellbeing at age 60–64 was captured by the Satisfaction With Life Scale (SWLS), Warwick-Edinburgh Mental Well Being Scale (WEMWBS) and the General Health Questionnaire (GHQ). A typology of 11 work-family groups was derived, across which there was greater variation for women. Adjusted for socioeconomic position, parental separation, adolescent internalising and externalising disorders, and health, men who had strong ties to paid work but no family had lower life satisfaction than those who combined work with parenthood and marriage (regression coefficient ?2.89 (95 %CI: ?5.04, ?0.74); standard deviation for SWLS?=?6.01). Women with weaker ties to paid work had lower life satisfaction, as did women who did not have children, compared to those who combined strong ties to paid work with marriage and parenthood. There were no significant associations between work-family life courses and WEMWBS or GHQ. This study shows that the way in which people combine work and family life may impact life satisfaction in early old age and highlights the need for policies that support combining work and family life. 相似文献
79.
A case of Clostridium perfringens sepsis and gas gangrene complicating chemotherapy for gestational choriocarcinoma is reported. The infection was eradicated using antibiotics, surgery, and hyperbaric oxygen therapy. The pathophysiology, diagnosis, and treatment of this unusual but often lethal complication are reviewed. 相似文献
80.