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71.
Eaddy Marc Zimmermann Thomas Sherwood Kaitlin D. Garg Vibhav Murphy Gail C. Nagappan Nachiappan Aho Alfred V. 《IEEE transactions on pattern analysis and machine intelligence》2008,34(4):497-515
There is a growing consensus that crosscutting concerns harm code quality. An example of a crosscutting concern is a functional requirement whose implementation is distributed across multiple software modules. We asked the question, "How much does the amount that a concern is crosscutting affect the number of defects in a program?" We conducted three extensive case studies to help answer this question. All three studies revealed a moderate to strong statistically significant correlation between the degree of scattering and the number of defects. This paper describes the experimental framework we developed to conduct the studies, the metrics we adopted and developed to measure the degree of scattering, the studies we performed, the efforts we undertook to remove experimental and other biases, and the results we obtained. In the process, we have formulated a theory that explains why increased scattering might lead to increased defects. 相似文献
72.
Carter Litchfield 《Journal of the American Oil Chemists' Society》1971,48(9):467-472
Correlation studies on lipolysis data from 24 species of Cruciferae seed triglycerides have revealed very regular positional
distribution patterns for oleic, linoleic and linolenic acids. When the ratio % 18:1 in β-position/% 18:1 in total triglycerides
for each species is plotted vs. the content of Category I acids (16:0, 18:0, plus all C20, C22 and C24 acids) in the total triglycerides, a smooth curve is obtained. Application of suitable statistical procedures yields a best-fitting
curve, from which an equation expressing the % 18:1 in the β-position as a function of the fatty acid composition of the total
triglycerides can be derived. The % 18:1 in the α-position is then readily calculated by difference. Similar distinctive relationships
have also been developed for linoleic and linolenic acids. Comparison of calculated and experimental results shows that the
relationships developed here are considerably more accurate than the previous Gunstone-Mattson and Evans hypotheses for estimating
the α,β-distributions of 18:1, 18:2 and 18:3 in Cruciferae seed triglycerides.
Presented in part at the AOCS meeting in San Francisco, California, April 1969. 相似文献
73.
Lipids were extracted from the mandibular fat body (jaw), the fatty forehead (melon), and the dorsal blubber of a Pacific
beaked whale (Berardius bairdi) and separated into lipid classes by preparative thin layer chromatography. The head fats were mixtures of wax esters and
triglycerides with a very small amount of diacyl glyceryl ether. The blubber fat contained 97% was ester and 3% triglyceride.
Gas liquid chromatography (GLC) of the intact lipid classes indicated an unusually low C26–C30 range for most of the jaw and melon wax esters compared to the more normal C32–C40 molecules found in the blubber. Distinctive lower molecular weight C24–C40 triglycerides occurred in the head fats vs. the usual C44–C58 range in the blubber. Most diacyl glyceryl ethers were in the C35–C46 range, below the molecular weight of hexadecyldipalmitoyl glyceryl ether (C48). GLC of the derived fatty acid methyl esters showed that the lower molecular weight neutral lipids in the head fats were
due to high levels of iso-10∶0, n−10∶0, iso-11∶0, iso-12∶0, n−12∶0, and iso-13∶0 acids. The wax ester fatty alcohols and the
alkoxy chains of the glyceryl ethers were mostly the C14–C20 chain lengths commonly observed in marine organisms. The distinctive medium chain neutral lipids in the jaw and melon fats
of this whale may be related to the postulated acoustical role of these tissues in echolocation. 相似文献
74.
T. W. Culp R. D. Harlow Carter Litchfield Raymond Reiser 《Journal of the American Oil Chemists' Society》1965,42(11):974-978
The triglycerides from ucuhuba kernel fat (Virola surinamensis) were analyzed using thinlayer adsorption chromatography (TLC) followed by gas-liquid chromatography (GLC). The triglycerides
were first separated into three fractions containing 0, 1, and 2 or more double bonds per molecule on silica gel TLC plates
impregnated with AgNO3. The total triglycerides and each individual TLC fraction were then analyzed by GLC for the molecular weights of their component
triglycerides and for their fatty acid composition. Quantitation of the TLC fractions was achieved by GLC analysis of their
fatty acids using an added internal standard and confirmed by solving simultaneous equations derived from GLC analysis of
their triglycerides and fatty acids.
Application of these combined chromatographic techniques separated the ucuhuba kernel fat into 23 triglyceride components.
Trimyristin and laurodimyristin comprised over half the total triglycerides, which was expected since the fat contained 20.0
mole % laurie and 71.3% myristic acids.
Presented at the AOCS Meeting in Houston, Texas, 1965.
Supported in part by grants from the National Institutes of Health (AM-06011) and the Corn Products Institute of Nutrition. 相似文献
75.
Jeremy McAdam Kaitlin McGinnis Rian Ory Kaelin Young Andrew D. Frugé Michael Roberts JoEllen Sefton 《Journal of the International Society of Sports Nutrition》2018,15(1):55
Background
Adequate dietary intake is important for promoting adaptation and prevention of musculoskeletal injury in response to large volumes of physical training such as Army Initial Entry Training (IET). The purpose of this study was to evaluate training volume and dietary intake and estimate energy balance in Army IET soldiers.Methods
Dietary intake was assessed by collecting diet logs for three meals on each of three, non-consecutive days during the first week of IET. Training volume was measured across 13?weeks of training using Actigraph wGT3X accelerometers. Training intensity was classified using Sasaki vector magnitude three cut points. Energy expenditure estimates were calculated during weeks two and three of training using the modified Harris-Benedict equation and by estimation of active energy expenditure using metabolic equivalents for each classification of physical activity. All data is presented as mean?±?standard deviation.Results
A total of 111 male soldiers (ht. =?±?173?±?5.8?cm, age?=?19?±?2?years, mass?=?71.6. ± 12.4?kg) completed diet logs and were monitored with Actigraphs. IET soldiers performed on average 273?±?62?min low, 107?±?42?min moderate, 26?±?22?min vigorous, and 10?±?21?min of very vigorous intensity physical activity daily across 13?weeks. The estimated total daily energy expenditure was on average 3238?±?457 kcals/d during weeks two and three of IET. Compared to week one caloric intake, there was a caloric deficit of 595?±?896 kcals/d on average during weeks two and three of IET. Regression analysis showed that body weight was a significant predictor for negative energy balance (adj. R2?=?0.54, p?<?0.001), whereby a 1?kg increase in body mass was associated with a 53?kcal energy deficit.Conclusions
Based on week one dietary assessment, IET soldiers did not consume adequate calories and nutrients to meet training needs during red phase (weeks one through three). This may directly affect soldier performance and injury frequency. IET soldiers undergo rigorous training, and these data may help direct future guidelines for adequate nourishment to optimize soldier health and performance.76.
Litchfield Damien; Ball Linden J.; Donovan Tim; Manning David J.; Crawford Trevor 《Canadian Metallurgical Quarterly》2010,16(3):251
Double reading of chest x-rays is often used to ensure that fewer abnormalities are missed, but very little is known about how the search behavior of others affects observer performance. A series of experiments investigated whether radiographers benefit from knowing where another person looked for pulmonary nodules, and whether the expertise of the model providing the search behavior was a contributing factor. Experiment 1 compared the diagnostic performance of novice and experienced radiographers examining chest x-rays and found that both groups performed better when shown the search behavior of either a novice radiographer or an expert radiologist. Experiment 2 established that benefits in performance only arose when the eye movements shown were related to the search for nodules; however, only the novices' diagnostic performance consistently improved when shown the expert's search behavior. Experiment 3 reexamined the contribution of task, image, and the expertise of the model underlying this benefit. Consistent with Experiment 1, novice radiographers were better at identifying nodules when shown either a na?ve's search behavior or an expert radiologist's search behavior, but they demonstrated no improvement when shown a na?ve model not searching for nodules. Our results suggest that although the benefits of this form of attentional guidance may be short-lived, novices can scaffold their decisions based on the search behavior of others. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Maude Perreault Kaitlin Roke Alaa Badawi Daiva E. Nielsen Salma A. Abdelmagid Ahmed El-Sohemy David W. L. Ma David M. Mutch 《Lipids》2014,49(3):255-263
Inflammation is a recognized risk factor for the development of chronic diseases, such as type 2 diabetes and atherosclerosis. Evidence suggests that individual fatty acids (FA) may have distinct influences on inflammatory processes. The goal of this study was to conduct a cross-sectional analysis to examine the associations between circulating FA and markers of inflammation in a population of young healthy Canadian adults. FA, high-sensitivity C-reactive protein (hsCRP), and cytokines were measured in fasted plasma samples from 965 young adults (22.6 ± 0.1 years). Gas chromatography was used to measure FA. The following cytokines were analyzed with a multiplex assay: regulated upon activation normal T cell expressed and secreted (RANTES/CCL5), interleukin 1-receptor antagonist (IL-1Ra), interferon-γ (IFN-γ), interferon-γ inducible protein 10 (IP-10), and platelet-derived growth factor β (PDGF-ββ). Numerous statistically significant associations (p < 0.05, corrected for multiple testing) were identified between individual FA and markers of inflammation using linear regression. Myristic (14:0), palmitic (16:0), palmitoleic (16:1n-7), and dihomo-γ-linolenic (20:3n-6) acids were positively associated with all markers of inflammation. In contrast, stearic acid (18:0) was inversely associated with hsCRP and RANTES, and linoleic acid (18:2n-6) was inversely associated with hsCRP, RANTES and PDGF-ββ. In conclusion, our results indicate that specific FA are distinctly correlated with various markers of inflammation. Moreover, the findings of this study suggest that FA profiles in young adults may serve as an early indicator for the development of future complications comprising an inflammatory component. 相似文献
78.
79.
This paper examines the conditions under which a dead zone, or a portion of the catalyst devoid of reactant, can form in a porous catalyst in which simultaneous reaction and diffusion are occurring. The condition that allows for the existence of a dead zone is defined by a critical Thiele modulus. When the Thiele modulus – the ratio of chemical reaction to diffusion – is greater than the critical Thiele modulus, a dead zone exists. This dead zone can be mathematically defined by a change of boundary conditions. We examine nth order reactions in isothermal infinite slabs, infinite cylinders, and spheres. In addition, we provide analytical concentration profiles and efficiency factors for zero-order reactions in non-isothermal infinite slabs (in the so-called low beta approximation). We also discuss some common errors and misconceptions associated with this phenomenon. 相似文献
80.
Electrothermal swing adsorption (ESA) of organic gases generated by industrial processes can reduce atmospheric emissions and allow for reuse of recovered product. Desorption energy efficiency can be improved through control of adsorbent heating, allowing for cost-effective separation and concentration of these gases for reuse. ESA experiments with an air stream containing 2000 ppm(v) isobutane and activated carbon fiber cloth (ACFC) were performed to evaluate regeneration energy consumption. Control logic based on temperature feedback achieved select temperature and power profiles during regeneration cycles while maintaining the ACFC's mean regeneration temperature (200 °C). Energy requirements for regeneration were independent of differences in temperature/power oscillations (1186-1237 kJ/mol of isobutane). ACFC was also heated to a ramped set-point, and the average absolute error between the actual and set-point temperatures was small (0.73%), demonstrating stable control as set-point temperatures vary, which is necessary for practical applications (e.g., higher temperatures for higher boiling point gases). Additional logic that increased the maximum power application at lower ACFC temperatures resulted in a 36% decrease in energy consumption. Implementing such control logic improves energy efficiency for separating and concentrating organic gases for post-desorption liquefaction of the organic gas for reuse. 相似文献