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71.
ATTEMPTED TO REPLICATE, IN A CROSS-NIGHT DESIGN, THE FINDING THAT EARLY-NIGHT REM-SLEEP DEPRIVATION LEADS TO MORE DREAMLIKE LATE NIGHT REM-SLEEP MENTATION. 8 SS WERE REM DEPRIVED ON NIGHT 1 AND PSEUDODEPRIVED ON NIGHT 3, WHILE 8 SS WERE RUN IN THE REVERSE ORDER. REPORTS OF MENTAL CONTENT WERE ELICITED FROM NREM AND REM SLEEP ON NIGHTS 2 AND 4, SS AND "WATCHERS" COMPLETED GOUGH ADJECTIVE CHECK LISTS (ACLS) ON S BEHAVIOR DURING DAYS 2 AND 4. DEPRIVATION PRODUCED NO SIGNIFICANT CHANGES IN WAKING BEHAVIOR, NREM OR REM MENTATION, OR IN THE SLEEP CYCLE. FINDINGS ARE DISCUSSED IN TERMS OF DREAM THEORY AND METHODOLOGICAL PROBLEMS OF DEPRIVATION RESEARCH. DEPRIVATION LOWERED DAYTIME ORAL TEMPERATURE, AND ACL RESPONSES PREDICTED PSYCHOLOGICAL COMPENSATION FROM DEPRIVATION. (19 REF.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
JOHN J. MECHOLSKY JR. S. W. FREIMAN ROY W. RICE 《Journal of the American Ceramic Society》1977,60(3-4):114-117
Fracture mechanics is combined with fracture surface analysis to analyze brittle failure of glass bars which were tested relative to the direction of grinding. Grinding essentially produces two sets of flaws from which failure occurs. In the most severe set, formed basically parallel to the grinding direction, the ratio of the average depth ( a ) to the half-width ( b ) is 0.5. In the less severe set, formed perpendicular to the grinding direction, the average a / b ratio is 1.6. In both sets the most severe flaws are generally associated with a particularly deep grinding groove or gouge. The strength reduction resulting from testing perpendicular to the grinding direction results from the larger flaw size and slightly higher stress-intensity factor resulting from the greater ellipticity of the flaws formed parallel to the grinding grooves and perpendicular to the tensile axis. Detailed analysis of these 2 sets of flaws causing failure of appropriately oriented specimens shows that (1) the fracture mirror radius, r , occurs at a constant stress-intensity level independent of flaw geometry; (2) unsymmetric fracture mirrors result from unsymmetric, irregular flaws leading to unsymmetric stress-intensity distributions; (3) is constant for semielliptical flaws; and (4) fracture energy calculated from an expression including mirror constants, the flaw-to-mirror size ratio, and the flaw geometry agrees with measured values over a wide range of a / b values. 相似文献
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In most social insects, intercolonial and interspecific aggression are expressions of territoriality. In termites, cuticular hydrocarbons (CHCs) have been extensively studied for their role in nestmate recognition and aggressive discrimination of nonnest-mates. More recently, molecular genetic techniques have made it possible to determine relatedness between colonies and to investigate the influence of genetics on aggression. In the Formosan subterranean termite, Coptotermes formosanus, however, the role of CHCs and genetic relatedness in inter-colony aggression has been ambiguous, suggesting the involvement of additional factors in nest-mate recognition. In this study we assess the range of aggression in this termite species and characterize the influence of genetic relatedness, CHC profiles and diet on aggression levels. We collected four colonies of C. formosanus, feeding either on bald cypress or birch, from three locations in Louisiana. Inter-colony aggression ranged from low to high. Differences in CHC profiles, as well as genetic distances between colonies determined by using microsatellite DNA markers, showed no significant correlation with aggression. However, termite diet (host tree) played a significant role in determining the level of aggression. Thus, two distantly related colonies, each feeding on different diets, showed high aggression that significantly diminished if they were fed on the same wood in the laboratory (spruce). Using headspace solid phase microextraction, we found three compounds from workers fed on birch that were absent in workers fed on spruce. Such diet-derived chemicals may be involved in the complex determination of nest-mate recognition in C. formosanus. 相似文献
76.
PETER ADEOYE SOPADE PETER JOHN HALLEY BRUCE ROBERT D'ARCY BHESH BHANDARI NOLA CAFFIN 《Journal of food process engineering》2004,27(4):284-309
The rheology of 10 Australian honeys was investigated at temperatures ?15C to 0C by a strain‐controlled rheometer. The honeys exhibited Newtonian behavior irrespective of the temperature, and follow the Cox–Merz rule. G″/G′ and ω are quadratically related, and the crossover frequencies for liquid to solid transformation and relaxation times were obtained. The composition of the honeys correlates well (r2 > 0.83) with the viscosity, and with 247 data sets (Australian and Greek honeys), the following equation was obtained: The viscosity of the honeys showed a strong dependence on temperature, and four models were examined to describe this. The models gave good fits (r 2 > 0.95), but better fits were obtained for the WLF model using Tg of the honeys and µg= 1011 Pa.s. The WLF model with its “universal values” poorly predicted the viscosity, and the implications of the measured rheological behaviors of the honeys in their processing and handling are discussed. 相似文献
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78.
JOHN N. SOFOS 《Journal of food science》1983,48(6):1684-1691
Frankfurters were manufactured with beef-pork mixtures using commercial procedures and with varying levels (2.5%, 2.0%, 1.5%, 1.0%) of two types of NaCl (granulated, flake). Parameters investigated included weight losses, composition, pH and microbial counts. At pH values above 5.7, salt levels >2.0% gave stable emulsions of high smokehouse yield (>92.9%). Reduction of salt level to <1.5%, or a low pH (<5.6), resulted in decreased smokehouse yield (86.4–91.3%), poor peelabillty and appearance, and, in certain instances, formation of fat caps. Flake NaCl did not improve emulsion properties compared to regular granulated salt. Microbial growth varied and reflected initial pH values and pH changes during storage (8°C). Variations in final product composition due to emulsion losses with reduced salt levels may have overshadowed the effect of salt level on total microbial growth. 相似文献
79.
KENNETH W. MILLER JUANELL N. BOYD JOHN G. BABISH DONALD J. LISK GILBERT S. STOEWSAND 《Journal of Food Safety》1983,5(3):131-143
Cabbage (Brassica oleracea var. capitata) was grown on soil (control) or municipal sewage sludge-treated plots. The cabbage was freeze-dried and analyzed for glucosinolate content and pattern. Results showed that cabbage grown on sludge-amended soil contained only half the glucosinolate content of cabbage grown on the control plot. The pattern of individual glucosinolates present was also altered. The sludge-grown cabbage glucosinolate extract was shown to be mutagenic in the non-activated test system of S. typhimurium TA 100. Extracts of both sludge-grown and control cabbage were shown to enhance the mutagenicity on a dose-response basis of aflatoxin B1 , benzo(a)pyrene, and captan. 相似文献
80.
SIDDARTH G. SUNDARESAN MULPURI V. RAO YONGLAI TIAN JOHN A. SCHREIFELS MARK C. WOOD KENNETH A. JONES ALBERT V. DAVYDOV 《Journal of Electronic Materials》2007,36(4):324-331
Rapid solid-state microwave annealing was performed for the first time on N+-, Al+-, and B+-implanted SiC, and the results were compared with the conventional furnace annealing. For microwave annealing, temperatures
up to 2,000 °C were attained with heating rates exceeding 600 °C/s. An 1,850 °C/35 s microwave anneal yielded a root-mean-square
(RMS) surface roughness of 2 nm, which is lower than the 6 nm obtained for 1,500 °C/15 min conventional furnace annealing.
For the Al implants, a minimum room-temperature sheet resistance (R
s
) of 7 kΩ/□ was measured upon microwave annealing. For the microwave annealing, Rutherford backscattering (RBS) measurements
indicated a better structural quality, and secondary-ion-mass-spectrometry (SIMS) boron implant depth profiles showed reduced
boron redistribution compared to the corresponding results of the furnace annealing. 相似文献