Blind men prefer a low waist-to-hip ratio
Karremans, J.C.T.M.; Frankenhuis, W.E.; Arons, A.M.M.
2010-01-01
Previous studies suggest that men in Western societies are attracted to low female waist-to-hip ratios (WHR). Several explanations of this preference rely on the importance of visual input for the development of the preference, including explanations stressing the role of visual media. We report evi
A GOOD ANTHROPOMETRIC INDEX FOR PREDICTI NG THE RISK OF TYPE 2 DIABETES: WAIST TO HIP RATIO
Ramadevi,; Padmini; Kali Vara Prasad
2015-01-01
An increasing trend of type2 Diabetes mellitus is seen with age . Visceral or central obesity is a very common risk factor for developing type 2 diabetes Mellitus. Hence any index which reliably measures obesity can be us ed as a tool to predict the risk of Diabetes. We have attempted to correlate waist to hip ratio (WHR) ...
Male sexual strategies modify ratings of female models with specific waist-to-hip ratios.
Brase, Gary L; Walker, Gary
2004-06-01
Female waist-to-hip ratio (WHR) has generally been an important general predictor of ratings of physical attractiveness and related characteristics. Individual differences in ratings do exist, however, and may be related to differences in the reproductive tactics of the male raters such as pursuit of short-term or long-term relationships and adjustments based on perceptions of one's own quality as a mate. Forty males, categorized according to sociosexual orientation and physical qualities (WHR, Body Mass Index, and self-rated desirability), rated female models on both attractiveness and likelihood they would approach them. Sociosexually restricted males were less likely to approach females rated as most attractive (with 0.68-0.72 WHR), as compared with unrestricted males. Males with lower scores in terms of physical qualities gave ratings indicating more favorable evaluations of female models with lower WHR. The results indicate that attractiveness and willingness to approach are overlapping but distinguishable constructs, both of which are influenced by variations in characteristics of the raters.
Female waist-to-hip ratio, body mass index and sexual attractiveness in China
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B.J. DIXSON, Baoguo LI, A.F. DIXSON
2010-04-01
Full Text Available Men and women at Northwest University (n = 751, Xi’an, China were asked to judge the attractiveness of photographs of female patients who had undergone micrograft surgery to reduce their waist-to-hip ratios (WHR. Micrograft surgery involves harvesting adipose tissue from the waist and reshaping the buttocks to produce a low WHR and an ‘hourglass’ female figure. This gynoid distribution of female body fat has been shown to correlate with measures of fertility and health. Significantly larger numbers of subjects, of both sexes, chose post-operative photographs, with lower WHRs, as more attractive than pre-operative photographs of the same women. Some patients had gained, and some had lost weight, post-operatively, with resultant changes in body mass index (BMI. However, these changes in BMI were not related to judgments of attractiveness. These results show that the hourglass female figure is rated as attractive in China, and that WHR, rather than BMI, plays a crucial role in such attractiveness judgments [Current Zoology 56 (2: 175–181, 2010].
Mojgan Gharipour; Nizal Sarrafzadegan; Masoumeh Sadeghi; Elham Andalib; Mohammad Talaie; Davood Shafie; Esmaiel Aghababaie
2013-01-01
This study aimed to investigate whether body mass index (BMI), waist circumference (WC), or waist to hip ratio (WHR) could be a better predictor of metabolic syndrome and, if so, what would be the cutoff points for these surrogates to appropriately differentiate metabolic syndrome in different age and sex subgroups. Methods. The present cross-sectional study was conducted on a sample of Isfahan Cohort Study (ICS). In total, 468 individuals (194 with and 274 subjects without metabolic syndrome...
Gharipour, Mojgan; Sarrafzadegan, Nizal; Sadeghi, Masoumeh; Andalib, Elham; Talaie, Mohammad; Shafie, Davood; Aghababaie, Esmaiel
2013-01-01
This study aimed to investigate whether body mass index (BMI), waist circumference (WC), or waist to hip ratio (WHR) could be a better predictor of metabolic syndrome and, if so, what would be the cutoff points for these surrogates to appropriately differentiate metabolic syndrome in different age and sex subgroups. Methods. The present cross-sectional study was conducted on a sample of Isfahan Cohort Study (ICS). In total, 468 individuals (194 with and 274 subjects without metabolic syndrome) according to the National Cholesterol Education Program's Adult Treatment Panel III (ATP-III) criteria were selected. Anthropometric indices were measured and plotted using receiver-operating characteristic (ROC) curves. Results. According to ROC curve analysis, WC and WHR parameters were better indicators of metabolic syndrome compared to BMI in women, whereas in men WHR had a lower discriminating value compared to the other two parameters. Among these three anthropometric parameters, BMI had a lower sensitivity and WC and WHR both had a higher sensitivity for predicting metabolic syndrome in women compared with in men. The cut points for WC were nearly equal in men and women, 90.3 versus 90.0, respectively. Women had higher cut points for BMI (28.5 kg/m(2)) compared to men (26.0 kg/m(2)). Our results showed the highest sensitivity and specificity for WC cut points specially in women. To predict metabolic syndrome, we looked into optimal age-specific cut points for BMI, WC, and WHR. The results indicated that WC had the highest discriminating value compared to other indicators in the different age subgroups. The optimal cut points for all three parameters gradually increased with age. Conclusion. Our results demonstrated that regardless of gender and age variables, WC could be a preferred parameter for predicting metabolic syndrome compared to BMI and WHR in Iranian population.
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A.S. Jahanlou
2015-07-01
Full Text Available Introduction & Objective: Proportion of Waist-to-Hip Ratio (WHR is an indicator of abdominal obesity, which is supported by some studies but rejected by others. The aim of this study was to examine the accuracy of the WHR and obtain suitable cut- off points for detecting obesity among adult Iranians. Materials & Methods: In this cross-sectional-descriptive study the sample consisted of 19366 adults. The data collection took place from 2009 to 2014, using Bioelectrical Impedance Analysis (BIA. The following data were obtained: WHR, Percentile of Body Fat (PBF, To-tal Fat (TF, and Soft Lean Mass (SLM. Sensitivity and specificity, based on World Health Organization’s Gold Standards were calculated for both sexes at three age groups. The data analysis included t-test, chi-square, ROC curve, and linear regression. Results: All study variables were correlated with each other. Age was only correlated with the WHR. Percentages of sensitivity and Negative Predictive Value (NPV were 84.2% and 85.6% in women; 21% and 50.7% in men. Increase in age was associated with increase in sensitivity in men and women, and NPV in men. The suitable cut-off points for men and women were found to be 87.5% and 83.5%, respectively. Conclusion: Waist-to-Hip ration is a suitable indictor of obesity for Iranian women but not men, especially among those who are under 59 years old. (Sci J Hamadan Univ Med Sci 2015; 22 (2: 144-151
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Ricardo Mondragón-Ceballos
2015-01-01
Full Text Available We studied if testosterone and estradiol concentrations are associated with specific female waist-to-hip ratios (WHRs and body mass indices (BMIs. Participants were 187 young women from which waist, hips, weight, and height were measured. In addition, participants informed on which day of their menstrual cycle they were and provided a 6 mL saliva sample. Ninety-one of them were in the follicular phase and 96 in the luteal phase. Only in the fertile phase of the menstrual cycle we found a significant interaction between testosterone and estradiol affecting WHR (b±s.e.=-0.000003±0.000001; t94=-2.12, adjusted R2=-0.008, P=0.03. Women with the highest levels of both hormones had the lowest WHRs, while women with low estradiol and high testosterone showed the highest WHRs. BMI significantly increased as testosterone increased in female in their nonfertile days.
Simpson, Victoria J; Brewer, Gayle; Hendrie, Colin A
2014-10-01
Waist-to-hip ratio (WHR) is an important ornament display that signals women's health and fertility. Its significance derives from human development as a bipedal species. This required fundamental changes to hip morphology/musculature to accommodate the demands of both reproduction and locomotion. The result has been an obstetric dilemma whereby women's hips are only just wide enough to allow the passage of an infant. Childbirth therefore poses a significant hip width related threat to maternal mortality/risk of gynecological injury. It was predicted that this would have a significant influence on women's sexual behavior. To investigate this, hip width and WHR were measured in 148 women (M age = 20.93 + 0.17 years) and sexual histories were recorded via questionnaire. Data revealed that hip width per se was correlated with total number of sexual partners, total number of one night stands, percentage of sexual partners that were one night stands, number of sexual partners within the context of a relationship per year sexually active, and number of one night stands per year sexually active. By contrast, WHR was not correlated with any of these measures. Further analysis indicated that women who predominantly engaged in one night stand behavior had wider hips than those who did not. WHR was again without effect in this context. Women's hip morphology has a direct impact on their risk of potentially fatal childbirth related injury. It is concluded that when they have control over this, women's sexual behavior reflects this risk and is therefore at least in part influenced by hip width.
Basraon, Sanmaan K.; Mele, Lisa; Myatt, Leslie; Roberts, James M.; Hauth, John C.; Leveno, Kenneth J.; Varner, Michael W.; Wapner, Ronald J.; Thorp, John M.; Peaceman, Alan M.; Ramin, Susan M.; Sciscione, Anthony; Tolosa, Jorge E.; Sorokin, Yoram
2017-01-01
Objective To determine the risk of gestational diabetes (GDM) and insulin resistance (IR) in obesity defined by body mass index (BMI), waist-to-hip ratio (WHR) or both combined. Methods Secondary analysis of a randomized multicenter trial of antioxidant supplementation versus placebo in nulliparous low-risk women to prevent pregnancy associated hypertension. Women between 9–16 weeks with data for WHR and BMI were analyzed for GDM (n=2300). Those with fasting glucose and insulin between 22–26 weeks (n=717) were analyzed for IR by homeostasis model assessment of insulin resistance (HOMA-IR; normal≤75thpercentile). WHR and BMI were categorized as normal (WHR<0.80; BMI<25kg/m2); overweight (WHR:0.8–0.84; BMI:25–29.9kg/m2); and obese (WHR≥0.85; BMI≥30kg/m2). ROC curves and logistic regression models were used. Results Compared with normal, the risks of GDM or IR were higher in obese by BMI or WHR. The subgroup with obesity by WHR but not by BMI had no increased risk of GDM. BMI was a better predictor of IR (AUC-0.71(BMI), 0.65(WHR), p=0.03) but similar to WHR for GDM (AUC-0.68(BMI), 0.63(WHR), p=0.18. Conclusion Increased WHR and BMI in early pregnancy are associated with IR and GDM. BMI is a better predictor of IR compared with WHR. Adding WHR to BMI does not improve its ability to detect GDM or IR. Trial Registration number NCT00135707 http://clinicaltrials.gov/ PMID:26352680
Al-Lawati, Jawad A; Jousilahti, Pekka
2008-01-01
There are no data on optimal cut-off points to classify obesity among Omani Arabs. The existing cut-off points were obtained from studies of European populations. To determine gender-specific optimal cut-off points for body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) associated with elevated prevalent cardiovascular disease (CVD) risk among Omani Arabs. A community-based cross-sectional study. The survey was conducted in the city of Nizwa in Oman in 2001. The study contained a probabilistic random sample of 1421 adults aged > or =20 years. Prevalent CVD risk was defined as the presence of at least two of the following three risk factors: hyperglycaemia, hypertension and dyslipidaemia. Logistic regression and receiver-operating characteristic (ROC) curve analyses were used to determine optimal cut-off points for BMI, WC and WHR in relation to the area under the curve (AUC), sensitivity and specificity. Over 87% of Omanis had at least one CVD risk factor (38% had hyperglycaemia, 19% hypertension and 34.5% had high total cholesterol). All three indices including BMI (AUC = 0.766), WC (AUC = 0.772) and WHR (AUC = 0.767) predicted prevalent CVD risk factors equally well. The optimal cut-off points for men and women respectively were 23.2 and 26.8 kg m-2 for BMI, 80.0 and 84.5 cm for WC, and 0.91 and 0.91 for WHR. To identify Omani subjects of Arab ethnicity at high risk of CVD, cut-off points lower than currently recommended for BMI, WC and WHR are needed for men while higher cut-off points are suggested for women.
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Paccaud Fred
2004-04-01
Full Text Available Abstract Background We sought to improve upon previously published statistical modeling strategies for binary classification of dyslipidemia for general population screening purposes based on the waist-to-hip circumference ratio and body mass index anthropometric measurements. Methods Study subjects were participants in WHO-MONICA population-based surveys conducted in two Swiss regions. Outcome variables were based on the total serum cholesterol to high density lipoprotein cholesterol ratio. The other potential predictor variables were gender, age, current cigarette smoking, and hypertension. The models investigated were: (i linear regression; (ii logistic classification; (iii regression trees; (iv classification trees (iii and iv are collectively known as "CART". Binary classification performance of the region-specific models was externally validated by classifying the subjects from the other region. Results Waist-to-hip circumference ratio and body mass index remained modest predictors of dyslipidemia. Correct classification rates for all models were 60–80%, with marked gender differences. Gender-specific models provided only small gains in classification. The external validations provided assurance about the stability of the models. Conclusions There were no striking differences between either the algebraic (i, ii vs. non-algebraic (iii, iv, or the regression (i, iii vs. classification (ii, iv modeling approaches. Anticipated advantages of the CART vs. simple additive linear and logistic models were less than expected in this particular application with a relatively small set of predictor variables. CART models may be more useful when considering main effects and interactions between larger sets of predictor variables.
Bleske-Rechek, April; Harris, Heather D; Denkinger, Kelly; Webb, Rose Mary; Erickson, Leah; Nelson, Lyndsay A
2011-08-24
We investigated women's facial attractiveness and body shape as a function of menstrual cycle phase, with the expectation from previous research that both would be enhanced during the high fertile phase. To control for the effects of women's daily behaviors on their appearance and waistline, we visited 37 normally cycling women twice in their dorm, where we photographed and measured them at low and high fertile days of their cycle immediately upon their waking. Seventy-four judges from a separate institution chose, for each woman, the picture they thought was more attractive. We analyzed a subset of 20 women who, by forward counting, had a High Fertility visit between Days 10-13 and a Low Fertility visit between Days 20-23; and we also analyzed a subsample of 17 women who, by reverse counting, had a High Fertility visit on the days leading to ovulation and a Low Fertility visit one week after ovulation. In neither set of analyses were women's waist- to-hip ratios lower nearer ovulation, and in neither set were women's high fertile pictures chosen at an above-chance rate by either male or female judges. We did not find evidence that facial attractiveness and waist-to-hip ratio are reliable physical cues of ovulatory status.
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April Bleske-Rechek
2011-07-01
Full Text Available We investigated women's facial attractiveness and body shape as a function of menstrual cycle phase, with the expectation from previous research that both would be enhanced during the high fertile phase. To control for the effects of women's daily behaviors on their appearance and waistline, we visited 37 normally cycling women twice in their dorm, where we photographed and measured them at low and high fertile days of their cycle immediately upon their waking. Seventy-four judges from a separate institution chose, for each woman, the picture they thought was more attractive. We analyzed a subset of 20 women who, by forward counting, had a High Fertility visit between Days 10–13 and a Low Fertility visit between Days 20–23; and we also analyzed a subsample of 17 women who, by reverse counting, had a High Fertility visit on the days leading to ovulation and a Low Fertility visit one week after ovulation. In neither set of analyses were women's waist-to-hip ratios lower nearer ovulation, and in neither set were women's high fertile pictures chosen at an above-chance rate by either male or female judges. We did not find evidence that facial attractiveness and waist-to-hip ratio are reliable physical cues of ovulatory status.
Czernichow, S.; Kengne, A.P.; Huxley, R.R.; Batty, G.D.; Galan, B.E. de; Grobbee, D.; Pillai, A.; Zoungas, S.; Marre, M.; Woodward, M.; Neal, B.; Chalmers, J.
2011-01-01
AIMS: The aim of this study was to compare the strength of associations and discrimination capability of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) with cardiovascular disease risk in individuals with type-2 diabetes. METHODS AND RESULTS: Eleven thousand, one hundre
Bacopoulou, Flora; Efthymiou, Vasiliki; Landis, Georgios; Rentoumis, Anastasios; Chrousos, George P
2015-05-04
Indices predictive of adolescent central obesity include waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR). Such reference data are lacking for Greek adolescents. The aim of this study was to develop age- and gender-specific WC, WHR and WHtR smoothed reference percentiles for abdominal obesity among Greek adolescents aged 12-17 years, to investigate possible obesity cut-offs of WHR and WHtR and to compare WC percentiles to other adolescent populations. A representative sample of 1610 high school adolescents (42.2% boys, 57.8% girls; mean age ± sd 14.4 ± 1.72 years) participated in this cross-sectional study in Attica, Greece, in 2013. Weight, height, body mass index (BMI), WC, hip circumference (HC), WHR and WHtR were measured and percentiles were calculated using the LMS method. The relation between WHR, WHtR and general obesity, as defined by the International Obesity Task Force, was investigated with receiver operating characteristic (ROC) analysis. The discriminating power of WHR and WHtR was expressed as area under the curve (AUC). Greek adolescents' WC measurements at the 50th and 90th percentile were compared with their counterparts' smoothed percentiles from Norway, Turkey, Poland, South India, Germany and Kuwait. Boys had significantly higher mean in all measures than girls, except for BMI where there was no statistical difference in terms of gender. BMI, WC and HC showed an increasing trend with age. WC leveled off in both genders at the age of 17 years. WHR and WHtR showed a continuous decrease with advancing age. WHtR was a better predictor for general obesity in both boys and girls (AUC 95% CI 0.945-0.992) than the WHR (AUC 95% CI 0.758-0.870); the WHtR cut-off of 0.5 had sensitivity 91% and specificity 95% for both genders and all age groups combined. International comparisons showed that Greek adolescents had relatively high levels of abdominal obesity in early-middle adolescence but this did not persist at
Sakurai, Y; Umeda, T; Shinchi, K; Honjo, S; Wakabayashi, K; Todoroki, I; Nishikawa, H; Ogawa, S; Katsurada, M
1997-12-01
We investigated the independent associations of total and beverage-specific ethanol consumption with body mass index (BMI) and waist-to-hip ratio (WHR) in middle-aged Japanese males, because of the scarcity of epidemiologic data in Japan. The subjects were 2227 male self-defense officials who received a pre-retirement health examination at the Self-Defense Forces Fukuoka, Kumamoto, and Sapporo Hospitals. Data on alcohol intake, smoking, physical activity, and past medical history were obtained from a self-reported questionnaire. Height, weight, and waist and hip girth measurements were obtained at the examination. Multiple linear regression analysis was employed. Alcohol intake was positively and strongly associated with WHR (p = 0.0001), but not associated with BMI after adjustment for lifestyle variables, including either BMI or WHR. Subjects who consumed 15 ml per day or more of shochu ethanol showed a larger WHR than never drinkers, and a dose-response relationship was found. Dose-response relationships to other beverages were not found. Dose-response relationships to other beverages were not found. These findings suggest that alcohol intake is strongly and independently associated with WHR, but not with BMI. Abdominal obesity was positively associated with shochu ethanol, but not with other types of alcohol.
Cornelissen, Piers L; Toveé, Martin J; Bateson, Melissa
2009-02-07
Body mass index (BMI) and waist-to-hip ratio (WHR) are two widely used anthropometric indices of body shape argued to convey different information about health and fertility. Both indices have also been shown to affect attractiveness ratings of female bodies. However, BMI and WHR are naturally positively correlated, complicating studies designed to identify their relative importance in predicting health and attractiveness outcomes. We show that the correlation between BMI and WHR depends on the assumed model of subcutaneous fat deposition. An additive model, whereby fat is added to the waist and hips at a constant rate, predicts a correlation between BMI and WHR because with increasing fat, the difference between the waist and hips becomes smaller relative to total width. This model is supported by longitudinal and cross-sectional data. We parameterized the function relating WHR to BMI for white UK females of reproductive age, and used this function to statistically decompose body shape into two independent components. We show that judgements of the attractiveness of female bodies are well explained by the component of curvaceousness related to BMI but not by residual curvaceousness. Our findings resolve a long-standing dispute in the attractiveness literature by confirming that although WHR appears to be an important predictor of attractiveness, this is largely explained by the direct effect of total body fat on WHR, thus reinforcing the conclusion that total body fat is the primary determinant of female body shape attractiveness.
Bellocco, Rino; Jia, Chongqi; Ye, Weimin; Lagerros, Ylva Trolle
2010-11-01
The health benefits of physical activity (PA) have been well documented. However, there is less research investigating whether or not these health benefits might differ among males and females or among subjects characterized by different levels of body mass index (BMI), waist-to-hip ratio (WHR), and waist circumference (WC). Baseline total PA, BMI, WHR and waist circumference were measured in 14,585 men and 26,144 women who participated in the Swedish National March. Their effects on all-cause mortality were analyzed with a follow-up time of almost 10 years. Sedentary men with a BMI ≥ 30 had a 98% (95% CI: 30-201%) increased risk of mortality compared to normal weight men with a high level of total PA. The same trend was observed for sedentary men with high WHR or waist circumference, compared to lean and highly active men. Sedentary women with a waist circumference of 88 cm or more had almost doubled, i.e. 97% (95% CI: 35-189%) increased mortality risk compared to physically active women with a waist circumference below 80 cm. BMI in men, but waist circumference in women better forecast all-cause mortality. We found no substantial effect modification between different measures of adiposity and physical activity-physical inactivity and obesity seem to increase total mortality risk independently and additively.
Burke, Linda; Lee, Andy H; Pasalich, Maria; Jancey, Jonine; Kerr, Deborah; Howat, Peter
2012-06-01
To investigate whether a home-based program, physical activity and nutrition for seniors (PANS), made positive changes to central obesity, measured by body mass index (BMI) and waist-to-hip ratio (WHR). A 6-month randomised controlled trial was conducted targeting overweight and sedentary older adults aged 60 to 70 years residing in low to medium socio-economic suburbs within metropolitan Perth. Intervention participants (n=248) received mailed materials and telephone/email support to improve nutrition and physical activity levels. Controls (n=230) received small incentives to complete baseline and post-intervention questionnaires. Both groups reported anthropometric measures following specific written instructions. Generalised estimating equation models were used to assess repeated outcomes of BMI and WHR over both time points. 176 intervention and 199 controls (response rate 78.5%) with complete data were available for analysis. After controlling for demographic and other confounding factors, the intervention group demonstrated a small (0.02) but significant reduction in WHR (p=0.03) compared to controls, no apparent change in BMI was evident for both groups. The 0.02 reduction in mean WHR corresponded to a 2.11 cm decrease in waist circumference for a typical hip circumference. PANS appears to improve the WHR of participants. Changes in BMI might require a longer term intervention to take effect, and/or a follow-up study to confirm its sustainability. Copyright © 2012 Elsevier Inc. All rights reserved.
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Ida Surakka
2011-10-01
Full Text Available Recent genome-wide association (GWA studies described 95 loci controlling serum lipid levels. These common variants explain ∼25% of the heritability of the phenotypes. To date, no unbiased screen for gene-environment interactions for circulating lipids has been reported. We screened for variants that modify the relationship between known epidemiological risk factors and circulating lipid levels in a meta-analysis of genome-wide association (GWA data from 18 population-based cohorts with European ancestry (maximum N = 32,225. We collected 8 further cohorts (N = 17,102 for replication, and rs6448771 on 4p15 demonstrated genome-wide significant interaction with waist-to-hip-ratio (WHR on total cholesterol (TC with a combined P-value of 4.79×10(-9. There were two potential candidate genes in the region, PCDH7 and CCKAR, with differential expression levels for rs6448771 genotypes in adipose tissue. The effect of WHR on TC was strongest for individuals carrying two copies of G allele, for whom a one standard deviation (sd difference in WHR corresponds to 0.19 sd difference in TC concentration, while for A allele homozygous the difference was 0.12 sd. Our findings may open up possibilities for targeted intervention strategies for people characterized by specific genomic profiles. However, more refined measures of both body-fat distribution and metabolic measures are needed to understand how their joint dynamics are modified by the newly found locus.
Kan, Mengyuan; Auer, Paul L; Wang, Gao T; Bucasas, Kristine L; Hooker, Stanley; Rodriguez, Alejandra; Li, Biao; Ellis, Jaclyn; Adrienne Cupples, L; Ida Chen, Yii-Der; Dupuis, Josée; Fox, Caroline S; Gross, Myron D; Smith, Joshua D; Heard-Costa, Nancy; Meigs, James B; Pankow, James S; Rotter, Jerome I; Siscovick, David; Wilson, James G; Shendure, Jay; Jackson, Rebecca; Peters, Ulrike; Zhong, Hua; Lin, Danyu; Hsu, Li; Franceschini, Nora; Carlson, Chris; Abecasis, Goncalo; Gabriel, Stacey; Bamshad, Michael J; Altshuler, David; Nickerson, Deborah A; North, Kari E; Lange, Leslie A; Reiner, Alexander P; Leal, Suzanne M
2016-08-01
Waist-to-hip ratio (WHR), a relative comparison of waist and hip circumferences, is an easily accessible measurement of body fat distribution, in particular central abdominal fat. A high WHR indicates more intra-abdominal fat deposition and is an established risk factor for cardiovascular disease and type 2 diabetes. Recent genome-wide association studies have identified numerous common genetic loci influencing WHR, but the contributions of rare variants have not been previously reported. We investigated rare variant associations with WHR in 1510 European-American and 1186 African-American women from the National Heart, Lung, and Blood Institute-Exome Sequencing Project. Association analysis was performed on the gene level using several rare variant association methods. The strongest association was observed for rare variants in IKBKB (P=4.0 × 10(-8)) in European-Americans, where rare variants in this gene are predicted to decrease WHRs. The activation of the IKBKB gene is involved in inflammatory processes and insulin resistance, which may affect normal food intake and body weight and shape. Meanwhile, aggregation of rare variants in COBLL1, previously found to harbor common variants associated with WHR and fasting insulin, were nominally associated (P=2.23 × 10(-4)) with higher WHR in European-Americans. However, these significant results are not shared between African-Americans and European-Americans that may be due to differences in the allelic architecture of the two populations and the small sample sizes. Our study indicates that the combined effect of rare variants contribute to the inter-individual variation in fat distribution through the regulation of insulin response.
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Russell Melissa
2010-12-01
Full Text Available Abstract Background Increased visceral adipose tissue (VAT and intramyocellular lipids (IMCL are associated with increased metabolic risk. Clinical and DXA body composition measures that are associated with VAT are generally even more strongly associated with subcutaneous adipose tissue (SAT reflecting general adiposity, and thus are not specific for VAT. Measures more strongly associated with VAT than SAT (thus more specific for VAT, and predictors of IMCL have not been reported. Subjects/Methods We studied 30 girls 12-18 years; 15 obese, 15 normal-weight. The following were assessed: (1 anthropometric measures: waist circumference at the umbilicus and iliac crest (WC-UC and WC-IC, waist-to-hip ratio (WHR, waist-to-height ratio (WHtR, (2 DXA measures: total fat, percent body fat (PBF, percent trunk fat (PTF, trunk-to-extremity fat ratio (TEFR, (3 MRI and 1H-MRS: VAT and SAT (L4-L5, soleus-IMCL. Results Group as a whole: WC, trunk fat and PBF were more strongly associated with SAT than VAT; none were specific for VAT. In contrast, PTF and TEFR were more significantly associated with VAT (r = 0.83 and 0.81 respectively, p Subgroup analysis: In obese girls, WHR and WHtR were more strongly correlated with VAT (r = 0.62 and 0.82, p = 0.04 and 0.001 than SAT (r = 0.41 and 0.73, p not significant and 0.007, and for DXA measures, PTF and TEFR were more significantly associated with VAT (r = 0.70 and 0.72, p = 0.007 and 0.006 than SAT (r = 0.52 and 0.53, p = 0.07 and 0.06. In controls, PTF and TEFR were more strongly correlated with VAT (r = 0.79, p = 0.0004 for both than SAT (r = 0.71 and 0.72, p = 0.003 for both. WHR was associated with IMCL in obese girls (r = 0.78, p = 0.008, but not controls. Conclusion Overall, WHR (anthropometry, and PTF and TEFR (DXA are good surrogates for IMCL and for visceral fat respectively in adolescent girls.
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Paula Aballo Nunes Machado
2002-04-01
Full Text Available OBJETIVO: Avaliar as associações entre fatores de dieta e acúmulo de tecido adiposo na região abdominal. MÉTODOS: A partir de um inquérito de base domiciliar realizado no Município do Rio de Janeiro, RJ, em 1995 e 1996, foi investigada a dieta usual em 2.441 pessoas (42,8% homens e 57,2% mulheres entre 20 anos e 60 anos. Para tanto, utilizou-se um questionário semiquantitativo de freqüência de consumo alimentar, e aferiram-se altura, peso e perímetros de cintura e quadril. Considerou-se a relação cintura-quadril (RCQ inadequada para os homens que apresentassem RCQ acima de 0,95 e, para as mulheres, acima de 0,80. RESULTADOS: A RCQ inadequada associou-se positivamente a idade, tabagismo, índice de massa corporal e inversamente a escolaridade, renda e atividade física de lazer para ambos os sexos (pOBJECTIVES: To assess the association between diet factors and abdominal fat accumulation. METHODS: A household survey carried out in the city of Rio de Janeiro during 1995-1996. The usual diet of a sample of 2,441 individuals (42.8% men and 57.2% women, aged 20 to 60 years, was investigated using a food frequency questionnaire and data about height, weight, waist and hip perimeter was collected. The cut-off points for inadequate waist-to-hip ratio (WHR for men and women were 0.95 and 0.80, respectively. RESULTS: Inadequate WHR was positively associated with age, cigarette smoking, body mass index, and inversely associated with education level, income and leisure physical activity in both men and women (p<0.05. Inadequate WHR was not associated with lipids, carbohydrates and total fiber intake. Positive association was found with inadequate WHR and spirits consumption among menopause women (p<0.001, and the consumption of four or more glasses of beer per day in men (p<0.001. CONCLUSION: In agreement with other studies, alcohol intake was associated with abdominal fat accumulation.
Afsar, Baris; Elsurer, Rengin; Güner, Ertugrul; Kirkpantur, Alper
2011-11-01
We analyzed the relationships between body mass index (BMI), waist circumference (WC), waist-to-hip ratio, and conicity index and 24-hour urinary albumin excretion rate (UAER) and creatinine clearance. Cross-sectional study. Patients presenting to a state hospital. Study involved patients with type 2 diabetes. Study participants underwent medical history examination, measurement of office blood pressure (BP), measurement of anthropometric factors and calculations (including BMI, WC, waist-to-hip ratio, and conicity index), physical examination, biochemical analysis, and 24-hour urine specimen collection to determine creatinine clearance and UAER. In all, 202 patients with type 2 diabetes (male/female: 91/111, aged: 58.4 ± 10.1 years) were included. It was found that 24-hour UAER correlated with WC (rho: +0.176, P = .012), serum albumin (rho: -0.324, P BMI (rho: +0.191, P = .007), albumin level (rho: +0.365, P BMI (P = .008), presence of peripheral arterial disease (P = .021), fasting serum glucose level (P = .003), and uric acid level (P BMI was no longer associated with creatinine clearance. Among the anthropometric parameters, only an increase in WC was found to be independently related to 24-hour UAER. Although BMI was associated with creatinine clearance, this association was lost after creatinine clearance was corrected for body surface area. Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
DEFF Research Database (Denmark)
Pisinger, C; Toft, U; Jørgensen, Torben
2009-01-01
, height, and waist and hip circumference were measured. Self-reported tobacco consumption and lifestyle variables (dietary quality, energy intake, physical activity in leisure time and alcohol consumption) were registered. RESULTS: Daily smokers had a significantly lower BMI and significantly higher WH...... ratio than never smokers (Ptobacco consumption (Ptobacco consumption. The association between increasing WH ratio and increasing tobacco consumption was largely explained...... consumption, but these factors did largely explain the increasing WH ratio. The relationship between BMI and tobacco consumption is complex, and the public needs to be informed that smoking is not a 'diet'....
Institute of Scientific and Technical Information of China (English)
Xuehong Zhang; Ann W Hsing; Yutang Gao; Asif Rashid; Jie Deng; Enju Liu; Kai Wu; Lu Sun; Jiarong Cheng; Gloria Gridley
2005-01-01
OBJECTIVE To investigate the relationship between BMI, WHR and billary tract cancers (CBT).METHODS A population-based case-control study was conducted in urban Shanghai from June 1, 1997 to May 31, 2001 involving interviews with 627 new cases of biliary tract cancers aged 35 to 74 years and 959frequency-matched population controls by gender and age in five-year groups. All subjects were interviewed in person by trained interviewers using a structured questionnaire. An unconditional logistic regression was performed to calculate adjusted odds ratios (Ors) and 95% confidence intervals (Cis).RESULTS Obesity was associated with an increased risk of gallbladder cancer across adulthood at ages 20-29 and 30-39 in females. Compared with subjects in the lowest quartile of WHR, Ors for the highest quartile and P for trend for cancers of gallbladder and extrahepatic bile duct both reached significant levels among males and females.CONCLUSION Our observations in urban Shanghai suggested that obesity in early adult life may contribute to the risk of gallbladder cancer, and increased WHR may substantially elevated risk of cancers of the gallbladder and extrahepatic bile duct.
Bembenek, Jan Paweł; Karlinski, Michał; Niewada, Maciej; Kurkowska-Jastrzębska, Iwona; Członkowska, Anna
2017-09-08
We aimed to investigate whether increased waist-to-hip ratio (WHR), waist circumference (WC), or improper body mass index (BMI) may differently predict short-term outcomes in females and males with first-ever acute ischemic stroke. This was a retrospective study of consecutive patients (1109 females and 939 males) admitted for first-ever ischemic stroke between 2003 and 2015. Data were collected in a detailed hospital stroke registry. BMI of 18.5-24.9 kg/m(2) and gender-specific normal values of WHC and WC were used as references for comparisons. Logistic regression was used to calculate the odds of in-hospital death or being dead or dependent at discharge, adjusted for patients' age and prestroke disability. In both sexes a high WHR increased the odds of death or dependency at discharge (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.05-3.08 for females and 1.43; 95% CI, 1.00-2.04 for males), but not in-hospital death alone. Increased WC was significantly associated with lower odds of either death or death and dependency at discharge in females only (OR, .36; 95% CI, .22-.58 and .69; 95% CI, .48-.97, respectively). BMI did not show any clear predictive value in either sex. Our findings suggest that being overweight measured with WC is a strong predictor of good outcome in women but not in men. The WHR less consistently predicts stroke outcome, as it is not associated with death at discharge alone; however, the WHR seems to be of similar clinical relevance in both genders. BMI seems to have the least clinical value in predicting stroke outcome in both genders. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.
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Lin Wen-Yuan
2010-09-01
Full Text Available Abstract Background High-sensitivity C-reactive protein (hs-CRP is an easily measured inflammatory biomarker. This study compared the association of percent body fat mass (%FM, body mass index (BMI, waist circumference (WC, and waist-to-hip ratio (WHR with hs-CRP in a Taiwanese population. Methods A total of 1669 subjects aged 40-88 years were recruited in 2004 in a metropolitan city in Taiwan. The relationships between obesity indicators and a high level of hs-CRP were examined using multivariate logistic regression analysis. The upper quartile of the hs-CRP distributions was defined as the high category group. The areas under the curve (AUCs of the receiver operating characteristic curves were calculated for all obesity indicators to compare their relative ability to correctly classify subjects with a high level of hs-CRP. Results After multivariate adjustment, the odds ratio for %FM was the only significant indicator that was associated with a high level of hs-CRP in men (1.55, 95% CI: 1.07-2.25. All indicators were associated with a high level of hs-CRP in women. In men, the AUCs for %FM were significantly higher than those for BMI, WHR, and WC, when demographic and lifestyle behaviors were considered (p Conclusions Our study demonstrates that %FM is the only obesity indicator that is strongly associated with a high level of hs-CRP after adjusting for sociodemographic factors, lifestyle behaviors and components of metabolic syndrome in both genders in a Taiwanese population aged forty years and over. In men, %FM had the greatest ability to classify subjects with a high level of hs-CRP when only demographic and lifestyle behaviors were considered. Our study finding has important implications for the screening of obesity in community settings.
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叶家楷; 佟伟军; 张永红; 张绍艳
2012-01-01
Objective To explore the relationship between body mass index ( BMI), waist circumference (WC), waist to hip ratio (WHR) and glucose metabolism. Methods Total 32 villages in Kezuohou Banner and Naiman in Inner Mongolia were selected as study field and residents aged 20 and above were served as study subjects, demographic data and tife style including cigarette smoking and alcohol intake were investigated by face to face method. Their blood pressure, height, body weight, waist and hip circumference, were measured by standardized methods. Their blood samples were collected and fasting plasma glucose level, blood lipids and C-reactive protein were examined for all subjects. Multivariate Logistic regression analysis was used to evaluate relations between the three obesity indexes and diabetes mellitus(DM). Results Total 2 589 Mongolians aged 20 years or above were recruited as study subjects. The overall prevalence of diabetes and IFG was 3. 7% ( males 3. 9% ;females 3. 5% ) and 18. 5% (males 17.7% ;females 19.0% ) , respectively. The Multivariate logistic regression analysis showed that diabetes was significantly associated with high WHR ( odds ratio; 2. 120). IFG was significantly associated with high BMI (odds ratio; 1.624) and high WC(odds ratio; 1.472) in male; In female, diabetes was significantly associated with high WC(odds ratio;2. 336). Conclusions In male, WHR may be a risk factor for DM; BMI and WC may be risk factors for IFG. In female, WC may be the risk factor for DM.%目的 探讨蒙古族居民体质指数(BMI)、腰围(WC)和腰臀比(WHR)与糖代谢的相关性.方法 选择内蒙古科左后旗朝鲁吐乡和奈曼固日班花乡的32个行政村,对20岁以上居民进行调查.采用面对面调查方式,收集人口学特征资料以及吸烟、饮酒等生活方式,测量血压、身高、体质量、腰围和臀围.采集血标本,检测血糖、血脂、C-反应蛋白等指标的水平.采用多因素logistic回归评估3个肥胖指标与
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Nivaldo Ribeiro Villela
2006-02-01
Full Text Available PURPOSE: Obesity is associated with cardiovascular disease, affecting large arteries and the microcirculation. Waist circumference and body mass index are routinely employed as measures for assessing obesity-related health risk, whereas waist-to-hip ratio is not. We aimed to investigate the association between brachial vascular reactivity and body mass index, waist circumference, and waist-to-hip ratio. METHODS: Eighty-five volunteers (21 men/66 women, aged between 20 and 55 years, underwent determination of waist circumference, body mass index, waist-to-hip ratio, and endothelial function by venous occlusion plethysmography. Forearm blood flow was measured in response to intrabrachial artery infusions of 3 different concentrations of endothelium-dependent (acetylcholine 7.5, 15, and 30 mg/min and endothelium-independent (sodium nitroprusside 2, 4, and 8 mg/min vasodilators. RESULTS: There was an inverse correlation of body mass index and waist circumference with forearm blood flow increments after acetylcholine and sodium nitroprusside infusions, while waist-to-hip ratio showed an inverse correlation with forearm blood flow increments only after acetylcholine. When subjects older than 40 years (n = 25 were excluded from the analysis, the inverse correlation of body mass index with forearm blood flow increments after acetylcholine infusion no longer existed, while waist circumference and waist-to-hip ratio showed the same results observed before. CONCLUSION: The waist-to-hip ratio is probably a better estimator of endothelial dysfunction and possibly of cardiovascular risk than body mass index. These findings underscore the importance of routinely collecting hip circumference as an obesity index and risk estimator.OBJETIVO: A obesidade é associada a doenças cardiovasculares e compromete tanto a macro como a microcirculação. As medidas da cintura e do índice de massa corpórea são rotineiramente empregadas para avaliação do risco
Lam, Benjamin Chih Chiang; Koh, Gerald Choon Huat; Chen, Cynthia; Wong, Michael Tack Keong; Fallows, Stephen J
2015-01-01
Excess adiposity is associated with cardiovascular disease (CVD) risk factors such as hypertension, diabetes mellitus and dyslipidemia. Amongst the various measures of adiposity, the best one to help predict these risk factors remains contentious. A novel index of adiposity, the Body Adiposity Index (BAI) was proposed in 2011, and has not been extensively studied in all populations. Therefore, the purpose of this study is to compare the relationship between Body Mass Index (BMI), Waist Circumference (WC), Waist-to-Hip Ratio (WHR), Waist-to-Height Ratio (WHtR), Body Adiposity Index (BAI) and CVD risk factors in the local adult population. This is a cross sectional study involving 1,891 subjects (Chinese 59.1% Malay 22.2%, Indian 18.7%), aged 21-74 years, based on an employee health screening (2012) undertaken at a hospital in Singapore. Anthropometric indices and CVD risk factor variables were measured, and Spearman correlation, Receiver Operating Characteristic (ROC) curves and multiple logistic regressions were used. BAI consistently had the lower correlation, area under ROC and odd ratio values when compared with BMI, WC and WHtR, although differences were often small with overlapping 95% confidence intervals. After adjusting for BMI, BAI did not further increase the odds of CVD risk factors, unlike WC and WHtR (for all except hypertension and low high density lipoprotein cholesterol). When subjects with the various CVD risk factors were grouped according to established cut-offs, a BMI of ≥23.0 kg/m2 and/or WHtR ≥0.5 identified the highest proportion for all the CVD risk factors in both genders, even higher than a combination of BMI and WC. BAI may function as a measure of overall adiposity but it is unlikely to be better than BMI. A combination of BMI and WHtR could have the best clinical utility in identifying patients with CVD risk factors in an adult population in Singapore.
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Marcos A. S. Cabrera
2005-06-01
Full Text Available Este estudo analisa a associação entre a relação cintura-quadril (RCQ, a circunferência abdominal (CA e o índice de massa corporal (IMC com a mortalidade total e cardiovascular em 575 mulheres idosas ambulatoriais por um seguimento de cinco anos. Os maiores quartis de RCQ, CA e IMC, bem como as categorias pré-determinadas de IMC, foram analisados como variáveis preditivas e analisada a interferência de algumas variáveis confundidoras. Oitenta e oito mulheres morreram durante o seguimento (15,4%. As mulheres com baixo peso (IMC 0,97 estava associado com a maior mortalidade total, entretanto, na análise multivariada o aumento de RCQ apresentou uma associação independente com a mortalidade total, apenas entre as mulheres de 60 a 80 anos. Nenhuma medida antropométrica apresentou uma associação significativa com a mortalidade cardiovascular. Os resultados identificaram o baixo peso e a RCQ como preditores de mortalidade total em idosas, principalmente entre as mulheres com até 80 anos.This study examines the association between body mass index (BMI, waist-to-hip ratio (WHR, and waist circumference (WC and all-cause and cardiovascular mortality in elderly women in a 5-year longitudinal study of 575 female outpatients 60 years and over. The highest BMI, WHR, and WC quartiles and predefined BMI categories were analyzed as predictive variables. Death occurred in 88 (15.4%. Underweight (BMI 0.97 was associated with all-cause mortality. However, after adjustment for age, smoking, and previous cardiovascular diseases, the increase in WHR was positively associated only in women from 60 to 80 years of age. None of the anthropometric measurements was associated with cardiovascular mortality. The results indicate that underweight and increased waist-to-hip ratio were predictors of all-cause mortality in elderly women, mainly among those under 80 years.
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Benjamin Chih Chiang Lam
Full Text Available Excess adiposity is associated with cardiovascular disease (CVD risk factors such as hypertension, diabetes mellitus and dyslipidemia. Amongst the various measures of adiposity, the best one to help predict these risk factors remains contentious. A novel index of adiposity, the Body Adiposity Index (BAI was proposed in 2011, and has not been extensively studied in all populations. Therefore, the purpose of this study is to compare the relationship between Body Mass Index (BMI, Waist Circumference (WC, Waist-to-Hip Ratio (WHR, Waist-to-Height Ratio (WHtR, Body Adiposity Index (BAI and CVD risk factors in the local adult population.This is a cross sectional study involving 1,891 subjects (Chinese 59.1% Malay 22.2%, Indian 18.7%, aged 21-74 years, based on an employee health screening (2012 undertaken at a hospital in Singapore. Anthropometric indices and CVD risk factor variables were measured, and Spearman correlation, Receiver Operating Characteristic (ROC curves and multiple logistic regressions were used. BAI consistently had the lower correlation, area under ROC and odd ratio values when compared with BMI, WC and WHtR, although differences were often small with overlapping 95% confidence intervals. After adjusting for BMI, BAI did not further increase the odds of CVD risk factors, unlike WC and WHtR (for all except hypertension and low high density lipoprotein cholesterol. When subjects with the various CVD risk factors were grouped according to established cut-offs, a BMI of ≥23.0 kg/m2 and/or WHtR ≥0.5 identified the highest proportion for all the CVD risk factors in both genders, even higher than a combination of BMI and WC.BAI may function as a measure of overall adiposity but it is unlikely to be better than BMI. A combination of BMI and WHtR could have the best clinical utility in identifying patients with CVD risk factors in an adult population in Singapore.
Institute of Scientific and Technical Information of China (English)
洪忻; 李解权; 梁亚琼; 王志勇; 徐斐
2009-01-01
Objective To explore whether the increase of body mass index (BMI) , waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR) can predict a higher risk of developing hyperglycemia. Methods A population-based cross-sectional study was conducted on local residents above 35 years of age in three urban districts and one rural county in July 2004. The subjects who were non-hyperglycemia in the baseline survey were selected to follow the survey in July 2007. Multivariable logistic regression analysis and area under curve (AUC) of receivcr-operating characteristics (ROC) were used to evaluate the predictive value of BMI, WC, WHR and WHtR. Results Of 3727 subjects without hyperglycemia who had completed in the baseline survey, 3031 of them participated in the follow-up survey, with a follow-up rate of 81.3%. The Three-year cumulative incidence of hyperglycemia was 6.7%,with male 6.3% and female 7.0%. By multiple linear regression, on average, an increase in BMI, WC, WHR, WHtR of 1 unit was associated with a 0.015 mmol/L, 0.023 mmol/L, 1.923 mmol/L, 2.382 mmol/L increase in fasting plasma glucose, respectively. The risk of developing hyperglycemia increased along with the increase of all the four indexes. When compared with other three indexes, the group which WHtR was more than 0.5, had the highest risk (male OR= 1.998, 95%CI:1.231-3.212, female OR= 1.832,95%CI: 1.157-2.902) of developing hyperglycemia. Data from ROC curve analysis showed that the AUC of WHtR was the highest in both males and females. Conclusion The increase of BMI, WC, WHR and WHtR could predict the higher risk causing the development of hyperglycemia. WHtR might serve as a simple but most effective index of hyperglycemia.%目的 探讨南京市成年人BMI、腰围(WC)、腰臀比(WHR)和腰高比(WHtR)与高血糖发病危险的关系.方法 2004年7月对南京市3个城区和1个郊县的35岁以上居民开展横断面调查,对无高血糖的人群于2007年7月进行随
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Márcia Gonçalves Ferreira
2006-02-01
Full Text Available Avaliou-se a acurácia dos indicadores antropométricos de localização de gordura (circunferência da cintura e relação cintura/quadril como preditores de dislipidemias, apresentando seus pontos de corte. A amostra consistiu-se de 416 homens saudáveis, de 20 a 58 anos, doadores de sangue do hemocentro de Cuiabá, Mato Grosso, Brasil. Os lipídios séricos foram determinados por método enzimático. A análise dos dados foi feita através da curva ROC para identificar o melhor ponto de corte dos indicadores e a maior área estatisticamente significante sob a curva. Os melhores pontos de corte para relação cintura/quadril e circunferência da cintura foram 0,90 e 85cm, respectivamente. O IC95% da área sob a curva ROC entre a circunferência da cintura e a relação colesterol/HDL elevada incluiu o valor 0,50, limitando a capacidade da circunferência da cintura como preditor de dislipidemias. Valores de sensibilidade e especificidade foram melhores no grupo mais jovem. A relação cintura/quadril foi mais associada às dislipidemias do que a circunferência da cintura. Circunferência da cintura mostrou melhor poder discriminatório na detecção de hipertrigliceridemia. Os pontos de corte de melhor acurácia foram menores do que os estabelecidos pela Organização Mundial da Saúde.This study evaluated the accuracy of anthropometric fat location indices (waist circumference and waist-to-hip ratio as predictors of dyslipidemia, in addition to defining their respective cut-offs. The sample consisted of 416 healthy male blood donors from 20 to 58 years of age at the Blood Center in Cuiabá, capital of Mato Grosso State, Brazil. Serum lipids were determined through the enzymatic method. Data analysis through the ROC curve identified the best indicator and the cut-off with the largest statistically significant area under the ROC curve. The best cut-off points for waist-to-hip ratio and waist circumference were 0.90 and 85cm, respectively. The
body mass index and waist-to-hip ratio among adults of obowo ...
African Journals Online (AJOL)
Uwaifoh
2012-12-31
Dec 31, 2012 ... This study investigates the nutritional health status of adults in Obowo ... degree of obesity and are at a higher risk for cardiovascular ..... In fact, the comparative gender risk status as noted in this study, is similar to the reports.
Waist circumference, waist to hip ratio, and body mass index in the ...
African Journals Online (AJOL)
Chigo Okwuosa
involved three hundred and thirty eight apparently healthy adult Nigerians recruited within the University College Hospital and its environs .... substantial additional cardiovascular risk over and above the sum of ..... Age-Groups (Years) Gender.
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Shereen R Kamel
2017-01-01
Conclusion BMI, WC, and WHR measurements should be used and encouraged in the RA population. Our findings suggested that WHR was better associated with disease activity, disability, and severity than with other measures.
Surakka, Ida; Isaacs, Aaron; Karssen, Lennart C.; Laurila, Pirkka-Pekka P.; Middelberg, Rita P. S.; Tikkanen, Emmi; Ried, Janina S.; Lamina, Claudia; Mangino, Massimo; Igl, Wilmar; Hottenga, Jouke-Jan; Lagou, Vasiliki; van der Harst, Pim; Mateo Leach, Irene; Esko, Tonu; Kutalik, Zoltan; Wainwright, Nicholas W.; Struchalin, Maksim V.; Sarin, Antti-Pekka; Kangas, Antti J.; Viikari, Jorma S.; Perola, Markus; Rantanen, Taina; Petersen, Ann-Kristin; Soininen, Pasi; Johansson, Asa; Soranzo, Nicole; Heath, Andrew C.; Papamarkou, Theodore; Prokopenko, Inga; Toenjes, Anke; Kronenberg, Florian; Doering, Angela; Rivadeneira, Fernando; Montgomery, Grant W.; Whitfield, John B.; Kahonen, Mika; Lehtimaki, Terho; Freimer, Nelson B.; Willemsen, Gonneke; de Geus, Eco J. C.; Palotie, Aarno; Sandhu, Manj S.; Waterworth, Dawn M.; Metspalu, Andres; Stumvoll, Michael; Uitterlinden, Andre G.; Jula, Antti; Navis, Gerjan; Wijmenga, Cisca; Wolffenbuttel, Bruce H. R.; Taskinen, Marja-Riitta; Ala-Korpela, Mika; Kaprio, Jaakko; Kyvik, Kirsten O.; Boomsma, Dorret I.; Pedersen, Nancy L.; Gyllensten, Ulf; Wilson, James F.; Rudan, Igor; Campbell, Harry; Pramstaller, Peter P.; Spector, Tim D.; Witteman, Jacqueline C. M.; Eriksson, Johan G.; Salomaa, Veikko; Oostra, Ben A.; Raitakari, Olli T.; Wichmann, H. -Erich; Gieger, Christian; Jaervelin, Marjo-Riitta; Martin, Nicholas G.; Hofman, Albert; McCarthy, Mark I.; Peltonen, Leena; van Duijn, Cornelia M.; Aulchenko, Yurii S.; Ripatti, Samuli
2011-01-01
Recent genome-wide association (GWA) studies described 95 loci controlling serum lipid levels. These common variants explain similar to 25% of the heritability of the phenotypes. To date, no unbiased screen for gene-environment interactions for circulating lipids has been reported. We screened for v
I. Surakka (Ida); A.J. Isaacs (Aaron); L.C. Karssen (Lennart); P.-P.P. Laurila; R.P.S. Middelberg (Rita); E. Tikkanen (Emmi); J.S. Ried (Janina); C. Lamina (Claudia); M. Mangino (Massimo); W. Igl (Wilmar); J.J. Hottenga (Jouke Jan); V. Lagou (Vasiliki); P. van der Harst (Pim); I.M. Leach (Irene Mateo); T. Esko (Tõnu); Z. Kutalik (Zoltán); N.W. Wainwright (Nicholas); M.V. Struchalin (Maksim); A.-P. Sarin; A.J. Kangas (Antti); J. Viikari (Jorma); M. Perola (Markus); T. Rantanen (Taina); A.K. Petersen; P. Soininen (Pasi); A. Johansson (Åsa); N. Soranzo (Nicole); A.C. Heath (Andrew); T. Papamarkou (Theodore); I. Prokopenko (Inga); A. Tönjes (Anke); F. Kronenberg (Florian); A. Döring (Angela); F. Rivadeneira Ramirez (Fernando); G.W. Montgomery (Grant); J.B. Whitfield (John); M. Kähönen (Mika); T. Lehtimäki (Terho); N.B. Freimer (Nelson); G.A.H.M. Willemsen (Gonneke); E.J.C. de Geus (Eco); A. Palotie (Aarno); M.S. Sandhu (Manj); D. Waterworth (Dawn); A. Metspalu (Andres); M. Stumvoll (Michael); A.G. Uitterlinden (André); A. Jula (Antti); G. Navis (Gerjan); C. Wijmenga (Cisca); B.H.R. Wolffenbuttel (Bruce); M.-R. Taskinen; M. Ala-Korpela (Mika); J. Kaprio (Jaakko); K.O. Kyvik (Kirsten Ohm); D.I. Boomsma (Dorret); N.L. Pedersen (Nancy); U. Gyllensten (Ulf); J.F. Wilson (James); I. Rudan (Igor); H. Campbell (Harry); P.P. Pramstaller (Peter Paul); T.D. Spector (Timothy); J.C.M. Witteman (Jacqueline); J.G. Eriksson (Johan); V. Salomaa (Veikko); B.A. Oostra (Ben); O. Raitakari (Olli); H.E. Wichmann (Heinz Erich); C. Gieger (Christian); M.R. Järvelin; N.G. Martin (Nicholas); A. Hofman (Albert); M.I. McCarthy (Mark); Y.S. Aulchenko (Yurii); L. Peltonen (Leena Johanna); P. Tikka-Kleemola (Päivi); S. Ripatti (Samuli)
2011-01-01
textabstractRecent genome-wide association (GWA) studies described 95 loci controlling serum lipid levels. These common variants explain ~25% of the heritability of the phenotypes. To date, no unbiased screen for gene-environment interactions for circulating lipids has been reported. We screened for
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Surakka, I.; Isaacs, A.; Karssen, L. C.;
2011-01-01
Recent genome-wide association (GWA) studies described 95 loci controlling serum lipid levels. These common variants explain similar to 25% of the heritability of the phenotypes. To date, no unbiased screen for gene-environment interactions for circulating lipids has been reported. We screened fo...
Anoop, Shajith; Misra, Anoop; Bhatt, Surya Prakash; Gulati, Seema; Mahajan, Harsh; Prabakaran, Gokulraj
2017-01-01
We aimed to correlate plasma glucagon levels with anthropometric measures and abdominal adipose tissue depots. Nonobese males (n = 81; BMI skinfolds), whole-body DEXA (for body fat and fat-free mass), and MRI scan (for volumes of subcutaneous abdominal adipose tissue (SCAT) including superficial and deep, intra-abdominal visceral adipose tissue (including intraperitoneal adipose tissue (IPAT), retroperitoneal adipose tissue, liver span and fatty liver, and pancreatic volume)). Plasma glucose and glucagon, serum insulin, hepatic transaminases, and lipid profile were measured. Significantly higher levels of fasting and postprandial glucagon (p skinfold thickness, IPAT, and deep SCAT (p < 0.05; r(2) = 0.84). These observations in Asian Indians may have significance for diabetes therapies which impact glucagon levels.
Hooff, M.H.A. van; Voorhorst, F.J.; Kaptein, M.B.H.; Hirasing, R.A.; Koppenaal, C.; Schoemaker, J.
2000-01-01
Data on changes in hormone concentrations during the first years after menarche are scarce. We studied the relation between gynecological age (age minus age at menarche), hormone concentrations, and body measurements from the 1st to the 6th yr after menarche in 229 observations of girls with regular
Application of Performance Ratios in Portfolio Optimization
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Aleš Kresta
2015-01-01
Full Text Available The cornerstone of modern portfolio theory was established by pioneer work of Harry Markowitz. Based on his mean-variance framework, Sharpe formulated his well-known Sharpe ratio aiming to measure the performance of mutual funds. The contemporary development in computer’s computational power allowed to apply more complex performance ratios, which take into account also higher moments of return probability distribution. Although these ratios were proposed to help the investors to improve the results of portfolio optimization, we empirically demonstrated in our paper that this may not necessarily be true. On the historical dataset of DJIA components we empirically showed that both Sharpe ratio and MAD ratio outperformed Rachev ratio. However, for Rachev ratio we assumed only one level of parameters value. Different set-ups of parameters may provide different results and thus further analysis is certainly required.
Chen, Bang-Dang; Yang, Yi-Ning; Ma, Yi-Tong; Pan, Shuo; He, Chun-Hui; Liu, Fen; Ma, Xiang; Fu, Zhen-Yan; Li, Xiao-Mei; Xie, Xiang; Zheng, Ying-Ying
2015-06-01
This study aimed to identify the best single predictor of metabolic syndrome by comparing the predictive ability of various anthropometric and atherogenic parameters among a Uighur population in Xinjiang, northwest China. A total of 4767 Uighur participants were selected from the Cardiovascular Risk Survey (CRS), which was carried out from October, 2007, to March, 2010. Anthropometric data, blood pressure, serum concentration of serum total cholesterol (TC), triglycerides (TGs), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and fasting glucose were documented. Prevalence of metabolic syndrome and its individual components were confirmed according to International Diabetes Federation (IDF) criteria. Area under the receiver operating characteristic curve (AUC) of each variable for the presence of metabolic syndrome was compared. The sensitivity (Sen), specificity (Spe), distance in the receiver operating characteristic (ROC) curve, and cutoffs of each variable for the presence of metabolic syndrome were calculated. In all, 23.7% of men had the metabolic syndrome, whereas 40.1% of women had the metabolic syndrome in a Uighur population in Xinjiang; the prevalence of metabolic syndrome in women was significantly higher than that in men (P<0.001). In men, the waist-to-height ratio (WHtR) had the highest AUC value (AUC=0.838); it was followed by TGs/HDL-C (AUC=0.826), body mass index (BMI) (AUC=0.812), waist-to-hip ratio (WHR) (AUC=0.781), and body adiposity index (BAI) (AUC=0.709). In women, the TGs/HDL-C had the highest AUC value (AUC=0.815); it was followed by WHtR (AUC=0.780), WHR (AUC=0.730), BMI (AUC=0.719), and BAI (AUC=0.699). Similarly, among all five anthropometric and atherogenic parameters, the WHtR had the shortest ROC distance of 0.32 (Sen=85.40%, Spe=71.6%), and the optimal cutoff for WHtR was 0.55 in men. In women, TGs/HDL-C had the shortest ROC distance of 0.35 (Sen=75.29%, Spe=75.18%), and the optimal cutoff
Application of Performance Ratios in Portfolio Optimization
Aleš Kresta
2015-01-01
The cornerstone of modern portfolio theory was established by pioneer work of Harry Markowitz. Based on his mean-variance framework, Sharpe formulated his well-known Sharpe ratio aiming to measure the performance of mutual funds. The contemporary development in computer’s computational power allowed to apply more complex performance ratios, which take into account also higher moments of return probability distribution. Although these ratios were proposed to help the investors to improve the r...
Topology Optimized Architectures with Programmable Poisson's Ratio over Large Deformations
DEFF Research Database (Denmark)
Clausen, Anders; Wang, Fengwen; Jensen, Jakob Søndergaard
2015-01-01
Topology optimized architectures are designed and printed with programmable Poisson's ratios ranging from -0.8 to 0.8 over large deformations of 20% or more.......Topology optimized architectures are designed and printed with programmable Poisson's ratios ranging from -0.8 to 0.8 over large deformations of 20% or more....
Effective Basemetal Hedging: The Optimal Hedge Ratio and Hedging Horizon
Directory of Open Access Journals (Sweden)
Michaël Dewally
2008-12-01
Full Text Available This study investigates optimal hedge ratios in all base metal markets. Using recent hedging computation techniques, we find that 1 the short-run optimal hedging ratio is increasing in hedging horizon, 2 that the long-term horizon limit to the optimal hedging ratio is not converging to one but is slightly higher for most of these markets, and 3 that hedging effectiveness is also increasing in hedging horizon. When hedging with futures in these markets, one should hedge long-term at about 6 to 8 weeks with a slightly greater than one hedge ratio. These results are of interest to many purchasing departments and other commodity hedgers.
AERODYNAMIC OPTIMIZATION DESIGN OF LOW ASPECT RATIO TRANSONIC TURBINE STAGE
Institute of Scientific and Technical Information of China (English)
SONG Liming; LI Jun; FENG Zhenping
2006-01-01
The advanced optimization method named as adaptive range differential evolution (ARDE)is developed. The optimization performance of ARDE is demonstrated using a typical mathematical test and compared with the standard genetic algorithm and differential evolution. Combined with parallel ARDE, surface modeling method and Navier-Stokes solution, a new automatic aerodynamic optimization method is presented. A low aspect ratio transonic turbine stage is optimized for the maximization of the isentropic efficiency with forty-one design variables in total. The coarse-grained parallel strategy is applied to accelerate the design process using 15 CPUs. The isentropic efficiency of the optimum design is 1.6% higher than that of the reference design. The aerodynamic performance of the optimal design is much better than that of the reference design.
The Golden Ratio Optimizes Cardiomelic Form and Function
Directory of Open Access Journals (Sweden)
Jason Yongsheng Chan
2009-05-01
Full Text Available "nBoth cardiac structure and hand proportion have been linked with the Fibonacci Series and the associated Golden Ratio - the number 1.618 that has been postulated to be related to functional optimization. In this paper, evidence supporting the relation of the Golden Ratio to the hand and heart is presented. It is known that upper limb malformations are the commonest skeletal abnormalities in patients with congenital heart disease. Embryological studies on hand-heart syndromes have provided evidence for a cardiomelic developmental field, which is supported by candidate genes involved in patterning of the hand and heart. Precise molecular interactions govern a certain optimal model of cardiomelic development, for which the underlying physical rule remains unknown. It is hypothesized that the Golden Ratio may represent the mathematical basis for hand-heart development so as to achieve optimal form and function. Deregulation of this underlying patterning law may manifest as variation in hand-heart structure away from that as would be determined by the Golden Ratio. Altered hand proportion in turn may be of predictive value for cardiovascular defects and dysfunction.
A Global Optimization Algorithm for Sum of Linear Ratios Problem
Directory of Open Access Journals (Sweden)
Yuelin Gao
2013-01-01
Full Text Available We equivalently transform the sum of linear ratios programming problem into bilinear programming problem, then by using the linear characteristics of convex envelope and concave envelope of double variables product function, linear relaxation programming of the bilinear programming problem is given, which can determine the lower bound of the optimal value of original problem. Therefore, a branch and bound algorithm for solving sum of linear ratios programming problem is put forward, and the convergence of the algorithm is proved. Numerical experiments are reported to show the effectiveness of the proposed algorithm.
Radar antenna pointing for optimized signal to noise ratio.
Energy Technology Data Exchange (ETDEWEB)
Doerry, Armin Walter; Marquette, Brandeis
2013-01-01
The Signal-to-Noise Ratio (SNR) of a radar echo signal will vary across a range swath, due to spherical wavefront spreading, atmospheric attenuation, and antenna beam illumination. The antenna beam illumination will depend on antenna pointing. Calculations of geometry are complicated by the curved earth, and atmospheric refraction. This report investigates optimizing antenna pointing to maximize the minimum SNR across the range swath.
Interaction of Obesity and Central Obesity on Elevated Urinary Albumin-to-Creatinine Ratio
Nan Du; Hao Peng; Xiangqin Chao; Qiu Zhang; Honggang Tian; Hongmei Li
2014-01-01
BACKGROUND: Microalbuminuria was much more common among obese individuals indicating a probable association with obesity. However, association of microalbuminuria with interaction between obesity and central obesity has not yet been studied. DESIGN AND METHODS: A cross-sectional study was conducted in a 2889 general population aged ≥ 30 years. Obesity was defined as body mass index ≥ 28.0 kg/m2 and central obesity was defined as waist-to-hip ratio ≥ 0.85 for females and ≥ 0.90 for males. Both...
Optimization of pediatric chest radiographic images using optical densities ratio
Energy Technology Data Exchange (ETDEWEB)
Souza, Rafael T.F.; Miranda, Jose R.A. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Inst. de Biociencias de Botucatu; Pina, Diana R. [Faculdade de Medicina de Botucatu (UNESP), Botucatu, SP (Brazil). Hospital das Clinicas. Dept. de Doencas Tropicais e Diagnostico por Imagem; Duarte, Sergio B. [Centro Brasileiro de Pesquisas Fisicas (CBPF/MCT), Rio de Janeiro, RJ (Brazil)
2011-07-01
The aim of this study is the optimization of radiographic images for the pediatric patients in the age range between 0 and 1 years old, through Optical Density Ratio (ODR), considering that pediatric patients are overexposed to radiation in the repeated attempts to obtain radiographic images considered of good quality. The optimization of radiographic techniques was carried out with the RAP-PEPP (Realistic Analytical Phantom coupled to homogeneous Phantom Equivalent to Pediatric Patient) phantom in two incubators and one cradle. The data show that the clinical routine radiographic techniques generate low-quality images at up to 18.8% when evaluated by the ODRs, and increases in doses up to 60% when compared to the optimized techniques doses. (author)
Ocean's 16: Optimal protein:RNA ratio has near Redfield nitrogen:phosphorus ratio
Elser, J. J.; Loladze, I.
2010-12-01
One of the biosphere’s most intriguing patterns is the near equality of the atomic nitrogen:phosphorus ratio (N:P) found in waters throughout the deep ocean (~16) and its average in plankton in the upper ocean. When Redfield discovered this pattern 75 years ago, he suggested that it is driven by the cellular composition of plankton. However, no theoretical explanation for an N:P ~16 in microorganisms has ever been found. Moreover, recently it has been suggested that N:P ~16 may have no significance for either plankton nor for N/P cycling on geological time scales. Here we show that an N:P ratio of 16 emerges from fundamental biochemical and biomolecular properties: N in amino acids, N and P in nucleotides, and the square root of the ratio of the maximal translation and transcription rates. Our theoretical results are supported by a comprehensive compilation of literature data on microbial protein:rRNA ratios. Thus, the N:P ratio of ~16 appears to correspond to the biochemically optimal protein:RNA ratio for maximal growth rates for both prokaryotes and eukaryotes.
Optimal go/no-go ratios to maximize false alarms.
Young, Michael E; Sutherland, Steven C; McCoy, Anthony W
2017-06-29
Despite the ubiquity of go/no-go tasks in the study of behavioral inhibition, there is a lack of evidence regarding the impact of key design characteristics, including the go/no-go ratio, intertrial interval, and number of types of go stimuli, on the production of different response classes of central interest. In the present study we sought to empirically determine the optimal conditions to maximize the production of a rare outcome of considerable interest to researchers: false alarms. As predicted, the shortest intertrial intervals (450 ms), intermediate go/no-go ratios (2:1 to 4:1), and the use of multiple types of go stimuli produced the greatest numbers of false alarms. These results are placed within the context of behavioral changes during learning.
School Administration: Optimal Ratio of Centralization to Decentralization.
Kapto, A. E.
1990-01-01
Compares advantages and disadvantages of centralized and decentralized control in Soviet public schools. Recognizes that centralization concentrates the forces, funds, and available resources necessary for maximum achievement. Suggests that decentralization of administration can be optimized by delegating rights, duties, and responsibilities to…
Optimal Taylor-Couette flow: Radius ratio dependence
Monico, Rodolfo Ostilla; Jannink, Tim J G; van Gils, Dennis P M; Verzicco, Roberto; Grossmann, Siegfried; Sun, Chao; Lohse, Detlef
2013-01-01
Taylor-Couette flow with independently rotating inner (i) and outer (o) cylinders is explored numerically and experimentally to determine the effects of the radius ratio {\\eta} on the system response. Numerical simulations reach Reynolds numbers of up to Re_i=9.5 x 10^3 and Re_o=5x10^3, corresponding to Taylor numbers of up to Ta=10^8 for four different radius ratios {\\eta}=r_i/r_o between 0.5 and 0.909. The experiments, performed in the Twente Turbulent Taylor-Couette (T^3C) setup, reach Reynolds numbers of up to Re_i=2x10^6$ and Re_o=1.5x10^6, corresponding to Ta=5x10^{12} for {\\eta}=0.714-0.909. Effective scaling laws for the torque J^{\\omega}(Ta) are found, which for sufficiently large driving Ta are independent of the radius ratio {\\eta}. As previously reported for {\\eta}=0.714, optimum transport at a non-zero Rossby number Ro=r_i|{\\omega}_i-{\\omega}_o|/[2(r_o-r_i){\\omega}_o] is found in both experiments and numerics. Ro_opt is found to depend on the radius ratio and the driving of the system. At a drivi...
Heo, Moonseong; Kabat, Geoffrey C; Strickler, Howard D; Lin, Juan; Hou, Lifang; Stefanick, Marcia L; Anderson, Garnet L; Rohan, Thomas E
2015-03-01
Obesity is a risk factor for several cancers in postmenopausal women. We attempted to determine cutoffs of adiposity measures in relation to risk of obesity-related cancers among postmenopausal women and to examine the effects of hormone therapy (HT) use on the cutoffs, neither of which has been broadly studied. We used data from the Women's Health Initiative cohort (n=144,701) and applied Cox-proportional hazards regressions to each combination of 17 cancer types and 6 anthropometric measures (weight, body mass index [BMI], weight to height ratio, waist circumference, waist to hip ratio [WHR], and waist to height ratio). Interactions between the anthropometric measures and HT use were also examined. Cutoffs were determined by applying a grid search followed by a two-fold cross validation method. Survival ROC analysis of 5- and 10-year incidence followed. Breast, colorectal, colon, endometrium, kidney, and all cancers combined were significantly positively associated with all six anthropometric measures, whereas lung cancer among ever smokers was significantly inversely associated with all measures except WHR. The derived cutoffs of each obesity measure varied across cancers (e.g., BMI cutoffs for breast and endometrium cancers were 30 kg/m(2) and 34 kg/m(2), respectively), and also depended on HT use. The Youden indices of the cutoffs for predicting 5- and 10-year cancer incidence were higher among HT never users. Using a panel of different anthropometric measures, we derived optimal cut-offs categorizing populations into high- and low-risk groups, which differed by cancer type and HT use. Although the discrimination abilities of these risk categories were generally poor, the results of this study could serve as a starting point from which to determine adiposity cutoffs for inclusion in risk prediction models for specific cancer types.
Kabat, Geoffrey C.; Strickler, Howard D.; Lin, Juan; Hou, Lifang; Stefanick, Marcia L.; Anderson, Garnet L.; Rohan, Thomas E.
2015-01-01
Abstract Background: Obesity is a risk factor for several cancers in postmenopausal women. We attempted to determine cutoffs of adiposity measures in relation to risk of obesity-related cancers among postmenopausal women and to examine the effects of hormone therapy (HT) use on the cutoffs, neither of which has been broadly studied. Methods: We used data from the Women's Health Initiative cohort (n=144,701) and applied Cox-proportional hazards regressions to each combination of 17 cancer types and 6 anthropometric measures (weight, body mass index [BMI], weight to height ratio, waist circumference, waist to hip ratio [WHR], and waist to height ratio). Interactions between the anthropometric measures and HT use were also examined. Cutoffs were determined by applying a grid search followed by a two-fold cross validation method. Survival ROC analysis of 5- and 10-year incidence followed. Results: Breast, colorectal, colon, endometrium, kidney, and all cancers combined were significantly positively associated with all six anthropometric measures, whereas lung cancer among ever smokers was significantly inversely associated with all measures except WHR. The derived cutoffs of each obesity measure varied across cancers (e.g., BMI cutoffs for breast and endometrium cancers were 30 kg/m2 and 34 kg/m2, respectively), and also depended on HT use. The Youden indices of the cutoffs for predicting 5- and 10-year cancer incidence were higher among HT never users. Conclusion: Using a panel of different anthropometric measures, we derived optimal cut-offs categorizing populations into high- and low-risk groups, which differed by cancer type and HT use. Although the discrimination abilities of these risk categories were generally poor, the results of this study could serve as a starting point from which to determine adiposity cutoffs for inclusion in risk prediction models for specific cancer types. PMID:25587642
Directory of Open Access Journals (Sweden)
Bo Yang, Lingen Chen, Fengrui Sun
2011-03-01
Full Text Available Finite time exergoeconomic performance of an endoreversible intercooled regenerative Brayton cogeneration plant is optimized based on the model which is established using finite time thermodynamic in Part 1 of this paper. It is found that the optimal heat conductance allocation of the regenerator is zero. When the total pressure ratio and the heat conductance allocation of the regenerator are fixed, it is shown that there exist an optimal intercooling pressure ratio, and a group of optimal heat conductance allocations among the hot-, cold- and consumer-side heat exchangers and the intercooler, which correspond to a maximum dimensionless profit rate. When the total pressure ratio is variable, there exists an optimal total pressure ratio which corresponds to a double-maximum dimensionless profit rate, and the corresponding exergetic efficiency is obtained. The effects of the total heat exchanger conductance, price ratios and the consumer-side temperature on the double-maximum dimensionless profit rate and the corresponding exergetic efficiency are discussed. It is found that there exists an optimal consumer-side temperature which corresponds to a thrice-maximum dimensionless profit rate.
Optimized Pump Power Ratio on 2nd Order Pumping Discrete Raman Amplifier
Institute of Scientific and Technical Information of China (English)
Renxiang; Huang; Youichi; Akasaka; David; L.; Harris; James; Pan
2003-01-01
By optimizing pump power ratio between 1st order backward pump and 2nd order forward pump on discrete Raman amplifier, we demonstrated over 2dB noise figure improvement without excessive non-linearity degradation.
Extinction Ratio and Gain Optimization of Dual- Pump Degenerate-Idler Phase Sensitive Amplifiers
DEFF Research Database (Denmark)
Kang, Ning; Lund-Hansen, Toke; Seoane, Jorge;
2011-01-01
Numerical optimization of dual-pump degenerateidler phase sensitive amplifiers is performed for Al-doped and standard highly nonlinear fibers. Design considerations for operating the PSAs at an optimum combination of gain and extinction ratio are discussed.......Numerical optimization of dual-pump degenerateidler phase sensitive amplifiers is performed for Al-doped and standard highly nonlinear fibers. Design considerations for operating the PSAs at an optimum combination of gain and extinction ratio are discussed....
Coculture of osteoblasts and endothelial cells: optimization of culture medium and cell ratio
Ma, J.; Beucken, J.J. van den; Yang, F.; Both, S.K.; Cui, F.Z.; Pan, J.; Jansen, J.A.
2011-01-01
Vascularization strategies in cell-based bone tissue engineering depend on optimal culture conditions. The present study aimed to determine optimal cell culture medium and cell ratio for cocultures of human marrow stromal cells (HMSCs) and human umbilical vein endothelial cells (HUVECs) in view of
Matthew Lorig; Ronnie Sircar
2015-01-01
We study the finite horizon Merton portfolio optimization problem in a general local-stochastic volatility setting. Using model coefficient expansion techniques, we derive approximations for the both the value function and the optimal investment strategy. We also analyze the `implied Sharpe ratio' and derive a series approximation for this quantity. The zeroth-order approximation of the value function and optimal investment strategy correspond to those obtained by Merton (1969) when the risky...
Vasheghani-Farahani, Ali; Majidzadeh-A, Keivan; Masoudkabir, Farzad; Karbalai, Shahrokh; Koleini, Maryam; Aiatollahzade-Esfahani, Farah; Pashang, Mina; Hakki, Elham
2013-04-01
We aimed to compare the accuracy of a novel index defined by us, as a ratio of Sagittal abdominal diameter (SAD) and triceps skinfold thickness (TSF) with other indices of adiposity for prediction of presence, severity and extension of premature coronary artery disease (CAD). A cross-sectional study was conducted on 238 younger patients (females <55 years; males <45 years) who underwent coronary angiography. Anthropometric indices including TSF, SAD, waist circumference, and hip circumference were measured before catheterization and body mass index, waist-to-hip ratio, abdominal diameter index, index of central obesity as well as our proposed index, SAD-to-TSF ratio, were calculated accordingly. Evaluation of severity and extension of coronary stenosis was by Gensini score and extent score, respectively. After adjustment for age and sex in multivariate regression models, the SAD-to-TSF ratio was the best predictor for the presence (OR = 2.49, 95% CI = 1.44-4.30; p = 0.001) and extension (β = 1.10, p = 0.004) of premature CAD. TSF and the SAD-to-TSF ratio were the only indices that significantly predicted the Gensini score and the correlation remained significant even after adjustment for age and sex (β = -7.28, p < 0.0001 and β = 3.76, p < 0.0001, respectively). We showed that our proposed index, SAD-to-TSF ratio, has a substantially better accuracy than do the known indices of obesity like body mass index, waist circumference, and waist-to-hip ratio for the prediction of premature CAD. Furthermore, our index was the only index that positively correlated with the severity of premature CAD. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Orito, Yukiko; Yamamoto, Hisashi; Tsujimura, Yasuhiro; Kambayashi, Yasushi
The portfolio optimizations are to determine the proportion-weighted combination in the portfolio in order to achieve investment targets. This optimization is one of the multi-dimensional combinatorial optimizations and it is difficult for the portfolio constructed in the past period to keep its performance in the future period. In order to keep the good performances of portfolios, we propose the extended information ratio as an objective function, using the information ratio, beta, prime beta, or correlation coefficient in this paper. We apply the simulated annealing (SA) to optimize the portfolio employing the proposed ratio. For the SA, we make the neighbor by the operation that changes the structure of the weights in the portfolio. In the numerical experiments, we show that our portfolios keep the good performances when the market trend of the future period becomes different from that of the past period.
Institute of Scientific and Technical Information of China (English)
ZHANG Xu-ping; YU Yue-qing
2005-01-01
Optimization of structural parameters aimed at improving the load carrying capacity of spatial flexible redundant manipulators is presented in this paper. In order to increase the ratio of load to mass of robots, the cross-sectional parameters and constructional parameters are optimized respectively. The cross-sectional and configurational parameters are optimized simultaneously. The numerical simulation of a 4R spatial manipulator is performed. The results show that the load capacity of robots has been greatly improved through the optimization strategies proposed in this paper.
Dadaser-Celik, Filiz; Azgin, Sukru Taner; Yildiz, Yalcin Sevki
2016-12-01
Biogas production from food waste has been used as an efficient waste treatment option for years. The methane yields from decomposition of waste are, however, highly variable under different operating conditions. In this study, a statistical experimental design method (Taguchi OA9) was implemented to investigate the effects of simultaneous variations of three parameters on methane production. The parameters investigated were solid content (SC), carbon/nitrogen ratio (C/N) and food/inoculum ratio (F/I). Two sets of experiments were conducted with nine anaerobic reactors operating under different conditions. Optimum conditions were determined using statistical analysis, such as analysis of variance (ANOVA). A confirmation experiment was carried out at optimum conditions to investigate the validity of the results. Statistical analysis showed that SC was the most important parameter for methane production with a 45% contribution, followed by F/I ratio with a 35% contribution. The optimum methane yield of 151 l kg(-1) volatile solids (VS) was achieved after 24 days of digestion when SC was 4%, C/N was 28 and F/I were 0.3. The confirmation experiment provided a methane yield of 167 l kg(-1) VS after 24 days. The analysis showed biogas production from food waste may be increased by optimization of operating conditions.
Optimal design and installation of ultra high bypass ratio turbofan nacelle
Savelyev, Andrey; Zlenko, Nikolay; Matyash, Evgeniy; Mikhaylov, Sergey; Shenkin, Andrey
2016-10-01
The paper is devoted to the problem of designing and optimizing the nacelle of turbojet bypass engine with high bypass ratio and high thrust. An optimization algorithm EGO based on development of surrogate models and the method for maximizing the probability of improving the objective function has been used. The designing methodology has been based on the numerical solution of the Reynolds equations system. Spalart-Allmaras turbulence model has been chosen for RANS closure. The effective thrust losses has been uses as an objective function in optimizing the engine nacelle. As a result of optimization, effective thrust has been increased by 1.5 %. The Blended wing body aircraft configuration has been studied as a possible application. Two variants of the engine layout arrangement have been considered. It has been shown that the power plant changes the pressure distribution on the aircraft surface. It results in essential diminishing the configuration lift-drag ratio.
Energy Technology Data Exchange (ETDEWEB)
Cai Xiaoqing; Wang, Cheng-Liang; Chen, Hsiang-Hsin; Chien, Chia-Chi; Lai Shengfeng; Chen Yiyun; Hua, Tzu-En; Kempson, Ivan M; Hwu, Y [Institute of Physics, Academia Sinica, Nankang, Taipei 115, Taiwan (China); Yang, C S [Center for Nanomedicine, National Health Research Institutes, Miaoli, Taiwan (China); Margaritondo, G, E-mail: phhwu@sinica.edu.tw [Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)
2010-08-20
Monodisperse gold nanorods with high aspect ratio were synthesized by x-ray irradiation. Irradiation was first used to stimulate the creation of seeds. Afterward, nanorod growth was stimulated either by chemical reduction or again by x-ray irradiation. In the last case, the entire process took place without reducing agents. The shape of the final products could be controlled by modulating the intensity of the x-ray irradiation during the seed synthesis. In turn, the nanorod aspect ratio determines the absorption wavelength of the nanorods that can thus be optimized for different applications. Likewise, the aspect ratio influences the uptake of the nanorods by HeLa cells.
Simple Strehl ratio based method for pupil phase mask's optimization in wavefront coding system
Institute of Scientific and Technical Information of China (English)
Wenzi Zhang; Yanping Chen; Tingyu Zhao; Zi Ye; Feihong Yu
2006-01-01
@@ By applying the wavefront coding technique to an optical system,the depth of focus can be greatly increased.Several complicated methods have already been taken to optimize for the best pupil phase mask in ideal condition.Here a simple Strehl ratio based method with only the standard deviation method used to evaluate the Strehl ratio stability over the depth of focus is applied to optimize for the best coefficients of pupil phase mask in practical optical systems.Results of imaging simulations for optical systems with and without pupil phase mask are presented,and the sharpness of image is calculated for comparison.The optimized pupil phase mask shows good results in extending the depth of focus.
Directory of Open Access Journals (Sweden)
Xiaoyan Liu
2015-11-01
Full Text Available A hierarchical support vector regression (SVR model (HSVRM was employed to correlate the compositions and mechanical properties of bicomponent stents composed of poly(lactic-co-glycolic acid (PGLA film and poly(glycolic acid (PGA fibers for urethral repair for the first time. PGLA film and PGA fibers could provide ureteral stents with good compressive and tensile properties, respectively. In bicomponent stents, high film content led to high stiffness, while high fiber content resulted in poor compressional properties. To simplify the procedures to optimize the ratio of PGLA film and PGA fiber in the stents, a hierarchical support vector regression model (HSVRM and particle swarm optimization (PSO algorithm were used to construct relationships between the film-to-fiber weight ratio and the measured compressional/tensile properties of the stents. The experimental data and simulated data fit well, proving that the HSVRM could closely reflect the relationship between the component ratio and performance properties of the ureteral stents.
Lift-optimal aspect ratio of a revolving wing at low Reynolds number
Jardin, Thierry; Colonius, Tim
2016-11-01
Lentink & Dickinson (2009) showed that rotational acceleration stabilized the leading-edge vortex on revolving, low-aspect-ratio wings, and hypothesized that a Rossby number of around 3, which is achieved during each half-stroke for a variety of hovering insects, seeds, and birds, represents a convergent high-lift solution across a range of scales in nature. Subsequent work has verified that, in particular, the Coriolis acceleration is responsible for LEV stabilization. Implicit in these results is that there exists an optimal aspect ratio for wings revolving about their root, because it is otherwise unclear why, apart from possible physiological reasons, the convergent solution would not occur for an even lower Rossby number. We perform direct numerical simulations of the flow past revolving wings where we vary the aspect ratio and Rossby numbers independently by displacing the wing root from the axis of rotation. We show that the optimal lift coefficient represents a compromise between competing trends where the coefficient of lift increases monotonically with aspect ratio, holding Rossby number constant, but decreases monotonically with Rossby number, when holding aspect ratio constant. For wings revolving about their root, this favors wings of aspect ratio between 3 and 4. The authors gratefully acknowledge support from Fondation ISAE-Supaero.
Yasuda, Shinya; Todo, Synge
2013-12-01
We present a method that optimizes the aspect ratio of a spatially anisotropic quantum lattice model during the quantum Monte Carlo simulation, and realizes the virtually isotropic lattice automatically. The anisotropy is removed by using the Robbins-Monro algorithm based on the correlation length in each direction. The method allows for comparing directly the value of the critical amplitude among different anisotropic models, and identifying the universality more precisely. We apply our method to the staggered dimer antiferromagnetic Heisenberg model and demonstrate that the apparent nonuniversal behavior is attributed mainly to the strong size correction of the effective aspect ratio due to the existence of the cubic interaction.
2012-01-01
Background Synchronized bursting activity (SBA) is a remarkable dynamical behavior in both ex vivo and in vivo neural networks. Investigations of the underlying structural characteristics associated with SBA are crucial to understanding the system-level regulatory mechanism of neural network behaviors. Results In this study, artificial pulsed neural networks were established using spike response models to capture fundamental dynamics of large scale ex vivo cortical networks. Network simulations with synaptic parameter perturbations showed the following two findings. (i) In a network with an excitatory ratio (ER) of 80-90%, its connective ratio (CR) was within a range of 10-30% when the occurrence of SBA reached the highest expectation. This result was consistent with the experimental observation in ex vivo neuronal networks, which were reported to possess a matured inhibitory synaptic ratio of 10-20% and a CR of 10-30%. (ii) No SBA occurred when a network does not contain any all-positive-interaction feedback loop (APFL) motif. In a neural network containing APFLs, the number of APFLs presented an optimal range corresponding to the maximal occurrence of SBA, which was very similar to the optimal CR. Conclusions In a neural network, the evolutionarily selected CR (10-30%) optimizes the occurrence of SBA, and APFL serves a pivotal network motif required to maximize the occurrence of SBA. PMID:22462685
Directory of Open Access Journals (Sweden)
Dong Chao-Yi
2012-03-01
Full Text Available Abstract Background Synchronized bursting activity (SBA is a remarkable dynamical behavior in both ex vivo and in vivo neural networks. Investigations of the underlying structural characteristics associated with SBA are crucial to understanding the system-level regulatory mechanism of neural network behaviors. Results In this study, artificial pulsed neural networks were established using spike response models to capture fundamental dynamics of large scale ex vivo cortical networks. Network simulations with synaptic parameter perturbations showed the following two findings. (i In a network with an excitatory ratio (ER of 80-90%, its connective ratio (CR was within a range of 10-30% when the occurrence of SBA reached the highest expectation. This result was consistent with the experimental observation in ex vivo neuronal networks, which were reported to possess a matured inhibitory synaptic ratio of 10-20% and a CR of 10-30%. (ii No SBA occurred when a network does not contain any all-positive-interaction feedback loop (APFL motif. In a neural network containing APFLs, the number of APFLs presented an optimal range corresponding to the maximal occurrence of SBA, which was very similar to the optimal CR. Conclusions In a neural network, the evolutionarily selected CR (10-30% optimizes the occurrence of SBA, and APFL serves a pivotal network motif required to maximize the occurrence of SBA.
Global Optimization for Sum of Linear Ratios Problem Using New Pruning Technique
Directory of Open Access Journals (Sweden)
2009-02-01
Full Text Available A global optimization algorithm is proposed for solving sum of general linear ratios problem (P using new pruning technique. Firstly, an equivalent problem (P1 of the (P is derived by exploiting the characteristics of linear constraints. Then, by utilizing linearization method the relaxation linear programming (RLP of the (P1 can be constructed and the proposed algorithm is convergent to the global minimum of the (P through the successive refinement of the linear relaxation of feasible region and solutions of a series of (RLP. Then, a new pruning technique is proposed, this technique offers a possibility to cut away a large part of the current investigated feasible region by the optimization algorithm, which can be utilized as an accelerating device for global optimization of problem (P. Finally, the numerical experiments are given to illustrate the feasibility of the proposed algorithm.
Directory of Open Access Journals (Sweden)
Xinying Wang,
2012-01-01
Full Text Available Cassava residue from breweries is being generated in large amounts in Guangxi Province of China, and this has potential to cause serious environmental problems if disposed of improperly. Two-stage anaerobic fermentation is a promising method for the treatment of such residue. In this study, the effect of feed to microbes ratio (F/M ratio on the anaerobic acidogenic fermentation of cassava residue was studied to determine the optimal F/M ratio and to maximize the performance in a subsequent methanogenic stage. The experiments were carried out at the F/M ratios of 0.2, 0.61, 1.02, 2.05, 3.07, and 4.09 g cassava-TS/g sludge-VSS in six laboratory-scale, completely stirred, tank reactors (CSTR at mesophilic temperature (35°C. An F/M ratio of 1.02 g cassava-TS/g sludge-VSS resulted in the highest solid removal efficiency and VFA/COD ratio, while starch removal efficiency was still near 100 percent, and acidification was relatively high. As a further benefit, the VFA distribution was more suitable for the subsequent methanogenic fermentation stage.
Optimal r/b ratio of bend channel in centrifugal compressor
Institute of Scientific and Technical Information of China (English)
Suping WEN; Xiaowen HU; Yong ZHANG; Jun WANG; Tingbin LI
2008-01-01
A numerical investigation on the flow in a bend channel by coupling the impeller with the vaneless diffuser in a centrifugal compressor with different r/b ratios (bend radius r to bend channel width b) is presented. The jet-wake effect of the impeller outlet is considered and flow pattern in the bend channel and the performance of the centrifugal compressor stage are investigated. The results indicate that there is an optimal r/b ratio for increasing the stage efficiency to the highest for a specific compressor stage. The change in r/b ratio significantly affects the flow angle of the bend chan-nel outlet. The prime reason for the total pressure loss in the bend channel is the wall friction in the bend channel.
Institute of Scientific and Technical Information of China (English)
GUAN Hsin; WANG Bo; LU Pingping; XU Liang
2014-01-01
The identification of maximum road friction coefficient and optimal slip ratio is crucial to vehicle dynamics and control. However, it is always not easy to identify the maximum road friction coefficient with high robustness and good adaptability to various vehicle operating conditions. The existing investigations on robust identification of maximum road friction coefficient are unsatisfactory. In this paper, an identification approach based on road type recognition is proposed for the robust identification of maximum road friction coefficient and optimal slip ratio. The instantaneous road friction coefficient is estimated through the recursive least square with a forgetting factor method based on the single wheel model, and the estimated road friction coefficient and slip ratio are grouped in a set of samples in a small time interval before the current time, which are updated with time progressing. The current road type is recognized by comparing the samples of the estimated road friction coefficient with the standard road friction coefficient of each typical road, and the minimum statistical error is used as the recognition principle to improve identification robustness. Once the road type is recognized, the maximum road friction coefficient and optimal slip ratio are determined. The numerical simulation tests are conducted on two typical road friction conditions(single-friction and joint-friction) by using CarSim software. The test results show that there is little identification error between the identified maximum road friction coefficient and the pre-set value in CarSim. The proposed identification method has good robustness performance to external disturbances and good adaptability to various vehicle operating conditions and road variations, and the identification results can be used for the adjustment of vehicle active safety control strategies.
Kapelner, Adam; Krieger, Abba; Blanford, William J
2016-10-14
When measuring Henry's law constants (kH) using the phase ratio variation (PRV) method via headspace gas chromatography (GC), the value of kH of the compound under investigation is calculated from the ratio of the slope to the intercept of a linear regression of the inverse GC response versus the ratio of gas to liquid volumes of a series of vials drawn from the same parent solution. Thus, an experimenter collects measurements consisting of the independent variable (the gas/liquid volume ratio) and dependent variable (the GC(-1) peak area). A review of the literature found that the common design is a simple uniform spacing of liquid volumes. We present an optimal experimental design which estimates kH with minimum error and provides multiple means for building confidence intervals for such estimates. We illustrate performance improvements of our design with an example measuring the kH for Naphthalene in aqueous solution as well as simulations on previous studies. Our designs are most applicable after a trial run defines the linear GC response and the linear phase ratio to the GC(-1) region (where the PRV method is suitable) after which a practitioner can collect measurements in bulk. The designs can be easily computed using our open source software optDesignSlopeInt, an R package on CRAN.
Optimal Limb Length Ratio of Quadruped Robot Minimising Joint Torque on Slopes
Directory of Open Access Journals (Sweden)
Tadayoshi Aoyama
2009-01-01
Full Text Available This paper aims to determine an optimal structure for a quadruped robot, which will allow the robot’s joint torque sum to be minimised. An animal’s characteristic limb length ratio is a vital part of its overall morphology and the one that enables it to travel easily through its environment. For the same reason, a robot’s structure needs to be suitably designed for locomotion in its working environment. Joint torques are necessary to maintain the posture of the robot and to accelerate joint angles during walking motion, hence, minimisation of joint torques reduces energy consumption. We performed a numerical simulation in which we analysed the joint torques for various limb lengths and slope angles in order to determine the optimal structure of a robot walking on a slope. Our investigation determines that the optimal Ratio of Rear Leg Length (RRL can be derived by the use of a simulation designed to determine the physical structure of quadruped robot. Our analysis suggests that joint torque will increase as the slope angle becomes steeper if the rear legs of the robot are shorter than its forelegs, and that joint torque will decrease as the slope angle declines if the robot’s forelegs are shorter than its rear legs. Finally, experimental results validated our simulation analysis.
DoE optimization of a mercury isotope ratio determination method for environmental studies.
Berni, Alex; Baschieri, Carlo; Covelli, Stefano; Emili, Andrea; Marchetti, Andrea; Manzini, Daniela; Berto, Daniela; Rampazzo, Federico
2016-05-15
By using the experimental design (DoE) technique, we optimized an analytical method for the determination of mercury isotope ratios by means of cold-vapor multicollector ICP-MS (CV-MC-ICP-MS) to provide absolute Hg isotopic ratio measurements with a suitable internal precision. By running 32 experiments, the influence of mercury and thallium internal standard concentrations, total measuring time and sample flow rate was evaluated. Method was optimized varying Hg concentration between 2 and 20 ng g(-1). The model finds out some correlations within the parameters affect the measurements precision and predicts suitable sample measurement precisions for Hg concentrations from 5 ng g(-1) Hg upwards. The method was successfully applied to samples of Manila clams (Ruditapes philippinarum) coming from the Marano and Grado lagoon (NE Italy), a coastal environment affected by long term mercury contamination mainly due to mining activity. Results show different extents of both mass dependent fractionation (MDF) and mass independent fractionation (MIF) phenomena in clams according to their size and sampling sites in the lagoon. The method is fit for determinations on real samples, allowing for the use of Hg isotopic ratios to study mercury biogeochemical cycles in complex ecosystems.
Brewick, Patrick T.; Smyth, Andrew W.
2016-12-01
The authors have previously shown that many traditional approaches to operational modal analysis (OMA) struggle to properly identify the modal damping ratios for bridges under traffic loading due to the interference caused by the driving frequencies of the traffic loads. This paper presents a novel methodology for modal parameter estimation in OMA that overcomes the problems presented by driving frequencies and significantly improves the damping estimates. This methodology is based on finding the power spectral density (PSD) of a given modal coordinate, and then dividing the modal PSD into separate regions, left- and right-side spectra. The modal coordinates were found using a blind source separation (BSS) algorithm and a curve-fitting technique was developed that uses optimization to find the modal parameters that best fit each side spectra of the PSD. Specifically, a pattern-search optimization method was combined with a clustering analysis algorithm and together they were employed in a series of stages in order to improve the estimates of the modal damping ratios. This method was used to estimate the damping ratios from a simulated bridge model subjected to moving traffic loads. The results of this method were compared to other established OMA methods, such as Frequency Domain Decomposition (FDD) and BSS methods, and they were found to be more accurate and more reliable, even for modes that had their PSDs distorted or altered by driving frequencies.
Goltsch, Mandy
Design denotes the transformation of an identified need to its physical embodiment in a traditionally iterative approach of trial and error. Conceptual design plays a prominent role but an almost infinite number of possible solutions at the outset of design necessitates fast evaluations. The corresponding practice of empirical equations and low fidelity analyses becomes obsolete in the light of novel concepts. Ever increasing system complexity and resource scarcity mandate new approaches to adequately capture system characteristics. Contemporary concerns in atmospheric science and homeland security created an operational need for unconventional configurations. Unmanned long endurance flight at high altitudes offers a unique showcase for the exploration of new design spaces and the incidental deficit of conceptual modeling and simulation capabilities. Structural and aerodynamic performance requirements necessitate light weight materials and high aspect ratio wings resulting in distinct structural and aeroelastic response characteristics that stand in close correlation with natural vibration modes. The present research effort evolves around the development of an efficient and accurate optimization algorithm for high aspect ratio wings subject to natural frequency constraints. Foundational corner stones are beam dimensional reduction and modal perturbation redesign. Local and global analyses inherent to the former suggest corresponding levels of local and global optimization. The present approach departs from this suggestion. It introduces local level surrogate models to capacitate a methodology that consists of multi level analyses feeding into a single level optimization. The innovative heart of the new algorithm originates in small perturbation theory. A sequence of small perturbation solutions allows the optimizer to make incremental movements within the design space. It enables a directed search that is free of costly gradients. System matrices are decomposed
Mauger, Stefan J; Dawson, Pam W; Hersbach, Adam A
2012-01-01
Noise reduction in cochlear implants has achieved significant speech perception improvements through spectral subtraction and signal-to-noise ratio based noise reduction techniques. Current methods use gain functions derived through mathematical optimization or motivated by normal listening psychoacoustic experiments. Although these gain functions have been able to improve speech perception, recent studies have indicated that they are not optimal for cochlear implant noise reduction. This study systematically investigates cochlear implant recipients' speech perception and listening preference of noise reduction with a range of gain functions. Results suggest an advantageous gain function and show that gain functions currently used for noise reduction are not optimal for cochlear implant recipients. Using the cochlear implant optimised gain function, a 27% improvement over the current advanced combination encoder (ACE) stimulation strategy in speech weighted noise and a 7% improvement over current noise reduction strategies were observed in babble noise conditions. The optimized gain function was also most preferred by cochlear implant recipients. The CI specific gain function derived from this study can be easily incorporated into existing noise reduction strategies, to further improve listening performance for CI recipients in challenging environments.
Gear ratio optimization and shift control of 2-speed I-AMT in electric vehicle
Gao, Bingzhao; Liang, Qiong; Xiang, Yu; Guo, Lulu; Chen, Hong
2015-01-01
Connecting a 2-speed transmission with the drive motor improves the dynamic and economic performance of electric passenger vehicles. A novel 2-speed I-AMT (Inverse Automated Manual Transmission) is studied, and the dry clutch is located at the rear of the transmission so that the traction interruption of traditional AMT can be cancelled. After the gear ratios are optimized using Dynamic Programming, gear shift control is addressed, and smooth shift process without torque hole is achieved through feed-forward and feed-back control of the clutch and the motor. Finally the proposed electric vehicle (EV) is compared with an EV with fixed-ratio gear box, and it is shown that the 2-speed AMT with a rear-mounted dry clutch has much better performance in terms of acceleration time, maximum speed and energy economy. The effect of clutch friction loss during shifting on the energy efficiency of the whole driving range is analyzed as well.
Directory of Open Access Journals (Sweden)
Young Min Kim
2014-09-01
Full Text Available This study investigated the effect of the built-in volume ratio of an expander on the performance of a dual-loop Rankine cycle system for the engine waste heat recovery of a vehicle. Varying vehicle operating conditions can cause a positive displacement expander to operate in both under- and over-expansion states. Therefore, analysis of the off-design performance of the expander is very important. Furthermore, the volume and weight of the expander must be considered in its optimization along with the efficiency. A simple modeling of the off-design operation of the expander showed that a built-in volume ratio that causes under-expansion rather than over-expansion at the target condition is more desirable.
Optimal C:N ratio for the production of red pigments by Monascus ruber.
Said, Farhan M; Brooks, John; Chisti, Yusuf
2014-09-01
The carbon-to-nitrogen (C:N) ratio in the biomass of microfungi tends to be quite different (e.g. 10-15) compared with the C:N ratio in the red pigments (e.g. >20) of the fungus Monascus ruber. Therefore, determining an optimal C:N ratio in the culture medium for maximizing the production of the pigments is important. A culture medium composition is established for maximizing the production of the red pigment by the fungus M. ruber ICMP 15220 in submerged culture. The highest volumetric productivity of the red pigment was 0.023 AU L(-1) h(-1) in a batch culture (30 °C, initial pH of 6.5) with a defined medium of the following composition (g L(-1)): glucose (10), monosodium glutamate (MSG) (10), MgSO4·7H2O (0.5), KH2PO4 (5), K2HPO4 (5), ZnSO4·7H2O (0.01), FeSO4·7H2O (0.01), CaCl2 (0.1), MnSO4·H2O (0.03). This medium formulation had a C:N mole ratio of 9:1. Under these conditions, the specific growth rate of the fungus was 0.043 h(-1) and the peak biomass concentration was 6.7 g L(-1) in a 7-day culture. The biomass specific productivity of the red pigment was 1.06 AU g(-1) h(-1). The best nitrogen source proved to be MSG although four other inorganic nitrogen sources were evaluated.
Telenkov, Sergey A; Alwi, Rudolf; Mandelis, Andreas
2013-10-01
Photoacoustic (PA) imaging of biological tissues using laser diodes instead of conventional Q-switched pulsed systems provides an attractive alternative for biomedical applications. However, the relatively low energy of laser diodes operating in the pulsed regime, results in generation of very weak acoustic waves, and low signal-to-noise ratio (SNR) of the detected signals. This problem can be addressed if optical excitation is modulated using custom waveforms and correlation processing is employed to increase SNR through signal compression. This work investigates the effect of the parameters of the modulation waveform on the resulting correlation signal and offers a practical means for optimizing PA signal detection. The advantage of coherent signal averaging is demonstrated using theoretical analysis and a numerical model of PA generation. It was shown that an additional 5-10 dB of SNR can be gained through waveform engineering by adjusting the parameters and profile of optical modulation waveforms.
Litvak, N; Rakhshandeh, A; Htoo, J K; de Lange, C F M
2013-09-01
Chronic subclinical levels of disease occur frequently in intensive swine production and compromise nutrient use efficiency. Feeding additional Met plus Cys (M+C) has been implicated in improving the response of the animal to immune system stimulation (ISS) because they can serve as substrates for generating compounds involved in the immune response, such as glutathione and acute phase proteins. A N-balance study was conducted to assess the optimal dietary Met to Met plus Cys ratio (M:M+C) during ISS in 20-kg pigs. Thirty-six pigs were fed 800 g/d of 1 of 5 M+C-limiting diets, containing graded levels of M:M+C (0.42, 0.47, 0.52, 0.57, and 0.62) and supplying 2.5 g/d of M+C. After adaptation, N balances were determined sequentially during a 5-d prechallenge period and 2 ISS periods of 3 and 4 d, respectively. To induce ISS, pigs were injected intramuscularly with repeated and increasing doses of Escherichia coli lipopolysaccharide. Eye temperature and blood profile confirmed effective ISS. During ISS period 1, ISS reduced the mean N balance more severely than ISS period 2 (8.7 ± 0.3 vs. 9.6 ± 0.4 g/d; P < 0.001) and was less than the prechallenge period (10.0 ± 0.2 g/d; P < 0.001). An interactive effect of ISS and diet on N balance was observed (P < 0.001). Based on quadratic-plateau regression analysis, the optimal dietary M:M+C was 0.57 ± 0.03 and 0.59 ± 0.02 for the prechallenge period and ISS period 2, respectively. The optimal dietary M:M+C for ISS period 1 was found to be greater than 0.62, indicating that the optimal M:M+C is greater during ISS. It is suggested that this is the result of preferential use of Met during ISS. In conclusion, ISS results in an increase in the optimal dietary M:M+C in growing pigs.
F-Ratio Test and Hypothesis Weighting: A Methodology to Optimize Feature Vector Size
Directory of Open Access Journals (Sweden)
R. M. Dünki
2011-01-01
Full Text Available Reducing a feature vector to an optimized dimensionality is a common problem in biomedical signal analysis. This analysis retrieves the characteristics of the time series and its associated measures with an adequate methodology followed by an appropriate statistical assessment of these measures (e.g., spectral power or fractal dimension. As a step towards such a statistical assessment, we present a data resampling approach. The techniques allow estimating σ2(F, that is, the variance of an F-value from variance analysis. Three test statistics are derived from the so-called F-ratio σ2(F/F2. A Bayesian formalism assigns weights to hypotheses and their corresponding measures considered (hypothesis weighting. This leads to complete, partial, or noninclusion of these measures into an optimized feature vector. We thus distinguished the EEG of healthy probands from the EEG of patients diagnosed as schizophrenic. A reliable discriminance performance of 81% based on Taken's χ, α-, and δ-power was found.
Directory of Open Access Journals (Sweden)
Amir Ghanifar
2016-06-01
Full Text Available Introduction The concentration of substances, including urea, creatinine, and uric acid, can be used as an index to measure toxic uremic solutes in the blood during dialysis and interdialytic intervals. The on-line monitoring of toxin concentration allows for the clearance measurement of some low-molecular-weight solutes at any time during hemodialysis.The aim of this study was to determine the optimal wavelength for estimating the changes in urea, creatinine, and uric acid in dialysate, using ultraviolet (UV spectroscopy. Materials and Methods In this study, nine uremic patients were investigated, using on-line spectrophotometry. The on-line absorption measurements (UV radiation were performed with a spectrophotometer module, connected to the fluid outlet of the dialysis machine. Dialysate samples were obtained and analyzed, using standard biochemical methods. Optimal wavelengths for both creatinine and uric acid were selected by using a combination of genetic algorithms (GAs, i.e., GA-partial least squares (GA-PLS and interval partial least squares (iPLS. Results The Artifitial Neural Network (ANN sensitivity analysis determined the wavelengths of the UV band most suitable for estimating the concentration of creatinine and uric acid. The two optimal wavelengths were 242 and 252 nm for creatinine and 295 and 298 nm for uric acid. Conclusion It can be concluded that the reduction ratio of creatinine and uric acid (dialysis efficiency could be continuously monitored during hemodialysis by UV spectroscopy.Compared to the conventional method, which is particularly sensitive to the sampling technique and involves post-dialysis blood sampling, iterative measurements throughout the dialysis session can yield more reliable data.
Dual energy contrast enhanced breast imaging optimization using contrast to noise ratio
Arvanitis, C. D.; Royle, G.; Speller, R.
2007-03-01
The properties of dual energy contrast enhanced breast imaging have been analyzed by imaging a 4 cm breast equivalent phantom consisting of adipose and glandular equivalent plastics. This phantom had superimposed another thin plastic which incorporated a 2 mm deep cylinder filled with iodinated contrast media. The iodine projected thicknesses used for this study was 3 mg/cm2. Low and high energy spectra that straddle the iodine K-edge were used. Critical parameters such as the energy spectra and exposure are discussed, along with post processing by means of nonlinear energy dependent function. The dual energy image was evaluated using the relative contrast to noise ratio of a 2.5 mm x 2.5 mm region of the image at the different iodine concentrations incorporating different breast composition with respect to the noniodinated areas. Optimum results were achieved when the low and high-energy images were used in such a way that relative contrast to noise ratio of the iodine with respect to the background tissue was maximum. A figure of merit suggests that higher noise levels can be tolerated at the benefit of lower exposure. Contrast media kinetics of a phantom incorporating a water flow of 20.4 ml/min through the plastic cylinder suggests that time domain imaging could be performed with this approach. The results suggest that optimization of dual energy contrast enhanced mammography has the potential to lead to the development of perfusion digital mammography.
Energy ratio analysis of genetically-optimized potato for ethanol production in the Chilean market
Energy Technology Data Exchange (ETDEWEB)
Contreras, A.; Diaz, G.; Gallardo, L.; Loaiza, R.
2010-07-01
The continuous increase in energy demand, the high cost of imported oil, and the growing concerns about climate change have sparked a number of initiatives from governments around the world to increase production of energy from renewable sources. Along these lines, the Chilean government is analyzing the introduction of a law to set a reference value of 5% of bio fuel production to be placed on the market by 2013. The analysis of different options to meet this new regulatory measure needs to consider different alternatives such as bio diesel and bio ethanol from crops or lignocellulose biomass. This paper analyzes the energy ratio of some of the most common crops grown in Chile that can be utilized for ethanol production. Using a methodology adapted to local conditions of agriculture and transportation, the results indicate that a potato cultivar specially bred for high yield, high starch and dry matter content can obtain a positive net energy balance with an energy ratio of 1.8. The results also show yields near 60 tons ha{sup -}1 which translate to approximately 9,000 L ha{sup -}1 of ethanol making the genetically optimized cultivar of potato a suitable local source for ethanol production. (Author) 48 refs.
DEFF Research Database (Denmark)
Ren, Jingzheng; Tan, Shiyu; Dong, Lichun
2010-01-01
the searching ability of basic particle swarm algorithm significantly. An example of utilizing the improved algorithm to solve the mathematical model was demonstrated; the result showed that it is efficient and convenient to optimize the reflux ratio for a distillation column by using the mathematical model......A mathematical model relating operation profits with reflux ratio of a stage distillation column was established. In order to optimize the reflux ratio by solving the nonlinear objective function, an improved particle swarm algorithm was developed and has been proved to be able to enhance...
Energy Technology Data Exchange (ETDEWEB)
Morimoto, Jun [Sankyo Corp., Tokyo (Japan); Suzuki, Mutsumi [Tohoku University, Miyagi (Japan). Department of Chemical Engineering
1999-03-10
To obtain maximum production under minimum utility-cost, the optimal operation of reflux ratio is considered for a batch distillation process. Pontryagin's maximum principle is one of the solutions to calculate such an optimal operation, but it requires extensive trial and error. In this paper, a faster algorithm is proposed to modify the initial values of Hamilton's multiplier. With the rapid growth of computer power, this algorithm will provide a way to realize the real-time optimization and control of the reflux ratio. To reduce the on-line calculation, a control table for the optimal operation can by calculated off-line as a function of state variables. These control methods provide the real optimal operation for a given evaluation function. (author)
Signal-To Ratio Improvement in NMR via Receiver Hardware Optimization.
Duensing, George Randall
The goal of this research was to increase available signal-to-noise ratio (SNR) in magnetic resonance imaging (MRI) by applying specific knowledge of the imaging system to improve receiver probes (coils) and receiving hardware. A brief history of improvements in MRI receiver and coil design is presented, including the transition from large linear volume coils to local surface coils and quadrature volume coils. Then quadrature surface coils are introduced and finally multi-coil arrays with independent acquisition systems. The research covers improvements in these areas and begins with a surface coil which is adjustable in size to optimize performance given the region of interest. By careful design of trombone-like coil elements, physical adjustment can be made without electrical adjustment. Second, new understanding of noise correlation and crosstalk between coils is developed and applied to multi-coil arrays. This provides the ability to increase available SNR for such systems. Third, a method for optimally combining multiple coils in a transverse (extending perpendicular to the static magnetic field) array into a single channel by proper signal combination is presented. This method is termed generalized quadrature because of the similarity of the method to standard quadrature combination, but with freedom in weighting and phasing in the combination process. Fourth, several methods of manipulating the multiple signals from an array to allow separation after acquisition are presented. These methods require new hardware demands but allow significant improvements in SNR for either transverse or longitudinal arrays. Fifth, several novel design methods are demonstrated, including an algorithm for impedance matching, a generalized quadrature combination method, transmission synchronized rf shielding and a bird-cage surface coil. Finally, the potential future applications and benefits of this research are presented.
Gao, Kai
2016-01-01
The conventional Perfectly Matched Layer (PML) is unstable for certain kinds of anisotropic media. This instability is intrinsic and independent of PML formulation or implementation. The Multi-axial PML (MPML) removes such instability using a nonzero damping coefficient in the direction parallel with the interface between a PML and the investigated domain. The damping ratio of MPML is the ratio between the damping coefficients along the directions parallel with and perpendicular to the interface between a PML and the investigated domain. No quantitative approach is available for obtaining these damping ratios for general anisotropic media. We develop a quantitative approach to determining optimal damping ratios to not only stabilize PMLs, but also minimize the artificial reflections from MPMLs. Numerical tests based on finite-difference method show that our new method can effectively provide a set of optimal MPML damping ratios for elastic-wave propagation in 2D and 3D general anisotropic media.
Institute of Scientific and Technical Information of China (English)
SHI NingZhong; LAI Min; ZHENG ShuRong; ZHANG BaoXue
2008-01-01
Most of the previous researches about portfolio analysis focus on short-selling.In fact,no short-selling is also important because short-selling is not allowed in stock markets of some coun-tries.This paper gives the sufficient and necessary conditions and proposes an optimal algorithm for Markowitz's mean-variance models and Sharpe's ratio with no short-selling.The optimal algorithm makes it easier to obtain the efficient frontiers with no short-selling.
Directory of Open Access Journals (Sweden)
Karen Olson
2012-01-01
Full Text Available Insulin resistance (IR is a risk factor for ischemic heart disease and diabetes and raises the triglyceride/high-density lipoprotein (TG/HDL ratio in adults, but is not well defined in children. Purpose. To investigate the TG/HDL ratios in children as an IR marker. Methods. Wausau SCHOOL Project assessed 99 prepubertal and 118 postpubertal children. The TG/HDL ratio was correlated with numerous risk factors. Results. TG/HDL ratio was significantly correlated with QUICKI, HOMA-IR, zBMI, waist-to hip ratio, systolic and diastolic BP, LDL size and LDL number. A group of 32 IR children (HOMA-IR > 1 SD from the mean, i.e., >2.45 had significantly higher TG/HDL (3.11 ± 1.77 compared to non-IR children (1.86 ± 0.75. A TG/HDL ratio of ≥2.0 identified 32 of the 40 children deemed IR by HOMA-IR (>2.45 with a sensitivity of 0.80 and a specificity of 0.66. Children with TG/HDL ratio ≥3 were heavier and had higher BP, glucose, HOMA-IR, LDL number, and lower HDL level, QUICKI, and LDL size, regardless of pubertal status. Conclusion. The TG/HDL ratio is strongly associated with IR in children, and with higher BMI, waist hip ratio, BP, and more athrogenic lipid profile.
X-ray dual energy spectral parameter optimization for bone Calcium/Phosphorus mass ratio estimation
Sotiropoulou, P. I.; Fountos, G. P.; Martini, N. D.; Koukou, V. N.; Michail, C. M.; Valais, I. G.; Kandarakis, I. S.; Nikiforidis, G. C.
2015-09-01
Calcium (Ca) and Phosphorus (P) bone mass ratio has been identified as an important, yet underutilized, risk factor in osteoporosis diagnosis. The purpose of this simulation study is to investigate the use of effective or mean mass attenuation coefficient in Ca/P mass ratio estimation with the use of a dual-energy method. The investigation was based on the minimization of the accuracy of Ca/P ratio, with respect to the Coefficient of Variation of the ratio. Different set-ups were examined, based on the K-edge filtering technique and single X-ray exposure. The modified X-ray output was attenuated by various Ca/P mass ratios resulting in nine calibration points, while keeping constant the total bone thickness. The simulated data were obtained considering a photon counting energy discriminating detector. The standard deviation of the residuals was used to compare and evaluate the accuracy between the different dual energy set-ups. The optimum mass attenuation coefficient for the Ca/P mass ratio estimation was the effective coefficient in all the examined set-ups. The variation of the residuals between the different set-ups was not significant.
Directory of Open Access Journals (Sweden)
A. Makhlouf
2016-03-01
Full Text Available Micronic and submicronic mineral fillers recently appeared as efficient reinforcing agents for polyolefins in addition to the benefit of bypassing the exfoliation/dispersion problem encountered in the case of incorporation of nanoscopic fillers such as clay. Submicronic-talc, designated as μ-talc, belongs to this kind of new fillers. This work was aimed at searching to optimize the crystallinity ratio of isotactic polypropylene in the presence of μ-talc in relation to the filler ratio of the composites and the cooling rate from the melt. In order to highlight the efficiency of the μ-talc on the crystallization of polypropylene comparison has been made with PP composites containing conventional talc particles. The study has been carried out on samples having μ-talc weight fractions covering the range 3–30%. In the context of optimizing the crystallinity ratio of the polypropylene matrix in the composites, calorimetric experiments have been planned using a full factorial design. The results were statistically processed by analysis of the variance via mathematical models for predicting the crystallinity ratio in relation to the cooling rate and the filler ratio. Contour graphs have been plotted to determine the effect of each parameter on crystallinity. The cooling rate proved to have a significantly stronger influence on crystallinity than the type and content of filler.
DEFF Research Database (Denmark)
de Los Milagros Bassani Molinas, Maria; Beer, Christiane; Hesse, F
2014-01-01
Large scale, transient gene expression (TGE) is highly dependent of the physiological status of a cell line. Therefore, intracellular nucleotide pools and ratios were used for identifying and monitoring the optimal status of a suspension cell line used for TGE. The transfection efficiency upon......-dependent manner and could be used to distinguish early- from late-passage cells. The observed effects were also dependent on the presence of serum in the culture. Nucleotide ratios were shown being applied to investigate the optimal passage number of cultured cell lines for achieving a maximum productivity...... polyethyleneimine (PEI)-mediated transient gene delivery into HEK-293 cells cultured in suspension was investigated to understand the effect of different culture and transfection conditions as well as the significance of the culture age and the quality of the cell line used. Based on two different bicistronic model...
An Application Of Optimization Based Expert System: Analysis Of Financial Ratios
Narasimhamurthi, N.; Dechen, R.
1988-03-01
This paper describes an application of rule-based expert system to the financial analysis of companies. The system was implemented on the Opine/Rubex system which uses ideas from optimization theory to drawing inferences. The paper provides a description of the expert system and the nature of the rule base. Typical analysis of two corporations is also presented.
Energy Technology Data Exchange (ETDEWEB)
Kim, Ye Won; Kim, Myung Soo; Yoo, Hyun Jun; Lee, Dae Hee; Cho, Gyu Seong [Dept. of Nuclear and Quantum Engineering, KAIST, Daejeon (Korea, Republic of); Moon, Myung Kook [Neutron Instrumentation Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2017-02-15
The scintillation efficiency of the polystyrene based plastic scintillator depends on the ratio of the wavelength shifters, organic fluors (PPO and POPOP). Thus, 24 samples of the plastic scintillator were fabricated in order to find out the optimum ratio of the wavelength shifters in the plastic scintillator. The fabricated plastic scintillators were trimmed through a cutting and polishing process. They were used in gamma energy spectrum measurement with the {sup 137}Cs emitting monoenergy photon with 662 keV for the comparison of the scintillation efficiency. As a result, it was found out that the scintillator sample with 1.00 g of PPO (2,5-Diphenyloxazole) and 0.50 g of POPOP (1,4-Bis(5-phnyl-2oxidazolyl)benzene) dissolved in 100 g of styrene solution has the optimum ratio in terms of the light yield of the polystyrene based plastic scintillator.
A New Approach to Online Scheduling: Approximating the Optimal Competitive Ratio
Günther, Elisabeth; Megow, Nicole; Wiese, Andreas
2012-01-01
We propose a new approach to competitive analysis in online scheduling by introducing the novel concept of online approximation schemes. Such a scheme algorithmically constructs an online algorithm with a competitive ratio arbitrarily close to the best possible competitive ratio for any online algorithm. We study the problem of scheduling jobs online to minimize the weighted sum of completion times on parallel, related, and unrelated machines, and we derive both deterministic and randomized algorithms which are almost best possible among all online algorithms of the respective settings. We also general- ize our techniques to arbitrary monomial cost functions and apply them to the makespan objective. Our method relies on an abstract characterization of online algorithms combined with various simplifications and transformations. We also contribute algorithmic means to compute the actual value of the best possi- ble competitive ratio up to an arbitrary accuracy. This strongly contrasts all previous manually obta...
Feng, Zhengfu; Dong, Chaohua; Wang, Linlin; Hu, Yanjiang; Zhu, Wei
2013-07-01
The optimal quantity of dietary lysine (Lys) and arginine (Arg), and the optimal ratio of dietary Lys to Arg for Pacific white shrimp Litopenaeus vannamei were investigated. Coated Lys and Arg were added to a basal diet (37.99% crude protein and 7.28% crude lipid) to provide graded levels of Lys and Arg. The experimental diets contained three Lys levels (2.51%, 2.11%, and 1.70% of total diet), and three Arg levels (1.41%, 1.80%, and 2.21% of total diet) and all combinations of these levels were tested. Pacific white shrimp, with a mean weight of 3.62±0.1 g, were randomly distributed in 36 fiberglass tanks with 30 shrimp per tank and reared on the experimental diets for 50 days. After the feeding trial, the growth performance, survival, feed conversion rate (FCR), body composition and protease and lipase activities in the hepatopancreases of the experimental shrimps were determined. The results show that weight gain (WG), specific growth rate (SGR), FCR, body protein, body Lys and Arg content were significantly affected by dietary Lys and Arg ( P 0.05). Therefore, according to our results, the optimal Lys and Arg quantities in the diet of Pacific white shrimp, L. vannamei, were considered to be 2.11%-2.51% and 1.80%-2.21%, respectively, and the optimal ratio to be 1:0.88-1:1.05.
Optimizing rib width to height and rib spacing to deck plate thickness ratios in orthotropic decks
Directory of Open Access Journals (Sweden)
Abdullah Fettahoglu
2016-12-01
Full Text Available Orthotropic decks are composed of deck plate, ribs, and cross-beams and are frequently used in industry to span long distances, due to their light structures and load carrying capacities. Trapezoidal ribs are broadly preferred as longitudinal stiffeners in design of orthotropic decks. They supply the required stiffness to the orthotropic deck in traffic direction. Trapezoidal ribs are chosen in industrial applications because of their high torsional and buckling rigidity, less material and welding needs. Rib width, height, spacing, thickness of deck plate are important parameters for designing of orthotropic decks. In the scope of this study, rib width to height and rib spacing to deck plate thickness ratios are assessed by means of the stresses developed under different ratios of these parameters. For this purpose a FE-model of orthotropic bridge is generated, which encompasses the entire bridge geometry and conforms to recommendations given in Eurocode 3 Part 2. Afterwards necessary FE-analyses are performed to reveal the stresses developed under different rib width to height and rib spacing to deck plate thickness ratios. Based on the results obtained in this study, recommendations regarding these ratios are provided for orthotropic steel decks occupying trapezoidal ribs.
The optimal exercise to rest ratios in repeated sprint ability training in youth soccer players.
Ruscello, Bruno; Partipilo, Filippo; Pantanella, Laura; Esposito, Mario; D'Ottavio, Stefano
2016-12-01
The aim of this study was to investigate the applicability of three different exercise to rest ratios in RSA training in youth soccer players, applying those ones already adopted in adult players, when performing three different sprinting modes (straight, shuttle and sprinting with changing of direction). Eighteen young trained male soccer players (Height: 1.66±0.07 m; weight: 58.22±7.64 kg; BMI 19.37±3.42 kg·m-2; age:14 years) participated to the study. In order to compare the different values of the time recorded, a Fatigue Index (FI) was used. Recovery times among trials in the sets were administered according to the 1:5, 1:3; 1:2 exercise to rest ratio, respectively. Significant differences among trials within each set (Repeated Measures Anova; Psprinting modalities when applying the investigated exercise to rest ratios (Factorial Anova; between; P>0.05). The results of this study confirm that the exercise to rest ratios considered in this study might be suitable to design effective testing protocols and training sessions aimed at the development of the RSA in youth soccer players, keeping the performances in the speed domain (FI%< ≈7-8%) but inducing the fatigue processes sought with this kind of training method.
Laser thermal annealing of Ge, optimized for highly activated dopants and diode ION/IOFF ratios
DEFF Research Database (Denmark)
Shayesteh, M.; O'Connell, D.; Gity, F.;
2014-01-01
The authors compared the influence of laser thermal annealing (LTA) and rapid thermal annealing (RTA) on dopant activation and electrical performance of phosphorus and arsenic doped n+/p junction. High carrier concentration above 1020 cm-3 as well as an ION/IOFF ratio of approximately 105 and ide...
Optimal education in times of ageing: The dependency ratio in the Uzawa–Lucas growth model
von Gaessler, A.E.; Ziesemer, T.
2016-01-01
The increasing share of retirees puts pressure on the shrinking working generation which will need to produce more output per worker to ensure a constant standard of living. We investigate the influence of a changing dependency ratio has on the time individuals spend in education and production. Lon
Effects of the optimal flexor/extensor ratio on G-tolerance
Park, Jung Sub; Choi, Jean; Kim, Jung Woon; Jeon, Sang Yun; Kang, Sunghwun
2016-01-01
[Purpose] The aim of this study was to examine the flexor/extensor ratio of the knee joints and compare it with the results of Korean Air Force students in G-tolerance test. [Subjects and Methods] The body composition of Korea Air Force students (n=77) was measured by an impedance method. A muscular function test was performed using a Humac Norm (USA) at angular speeds of 60°/sec and 240°/sec and an isokinetic muscular function test was also conducted. [Results] In the failed C and passing groups, muscle mass and fat percentages were significantly higher than those of students in the failed A group. The BMI of the failed C and passing groups were significantly higher than that of the failed A group. The group that passed had a significantly higher value of left knee 60°/sec flexion peak torque than the failed B group. Moreover, the total work of left knee extension of the failed C group and the passing group was significantly higher than that of the failed A group. The C group and the passing group had significantly higher values of the trunk 60°/sec flexor/extensor ratio than the failed A group, and the total work flexor/extensor ratio of the passing group was significantly higher than that of the failed A group. [Conclusions] Based on these results, balance the right and left knee flexor/extensor ratio, and a high flexor/extensor ratio of the trunk are required to endure a high G-tolerance test (+6G/30 sec). Moreover, an improvement in the maximum muscular strength is necessary to endure a situation of rapidly increasing acceleration in the early stage.
Directory of Open Access Journals (Sweden)
Sébastien Ménigot
2013-01-01
Full Text Available Ultrasound contrast imaging has provided more accurate medical diagnoses thanks to the development of innovating modalities like the pulse inversion imaging. However, this latter modality that improves the contrast-to-tissue ratio (CTR is not optimal, since the frequency is manually chosen jointly with the probe. However, an optimal choice of this command is possible, but it requires precise information about the transducer and the medium which can be experimentally difficult to obtain, even inaccessible. It turns out that the optimization can become more complex by taking into account the kind of generators, since the generators of electrical signals in a conventional ultrasound scanner can be unipolar, bipolar, or tripolar. Our aim was to seek the ternary command which maximized the CTR. By combining a genetic algorithm and a closed loop, the system automatically proposed the optimal ternary command. In simulation, the gain compared with the usual ternary signal could reach about 3.9 dB. Another interesting finding was that, in contrast to what is generally accepted, the optimal command was not a fixed-frequency signal but had harmonic components.
Using Optimal Ratio Mask as Training Target for Supervised Speech Separation
Xia, Shasha; Li, Hao; ZHANG Xueliang
2017-01-01
Supervised speech separation uses supervised learning algorithms to learn a mapping from an input noisy signal to an output target. With the fast development of deep learning, supervised separation has become the most important direction in speech separation area in recent years. For the supervised algorithm, training target has a significant impact on the performance. Ideal ratio mask is a commonly used training target, which can improve the speech intelligibility and quality of the separate...
Contrast-to-noise ratio optimization for a prototype phase-contrast computed tomography scanner
Energy Technology Data Exchange (ETDEWEB)
Müller, Mark, E-mail: mark-mueller@ph.tum.de; Yaroshenko, Andre; Velroyen, Astrid; Tapfer, Arne [Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Bech, Martin [Medical Radiation Physics, Lund University, Barngatan 2:1, 221 85 Lund (Sweden); Pauwels, Bart; Bruyndonckx, Peter; Sasov, Alexander [Bruker microCT, Kartuizersweg 3B, B-2550 Kontich (Belgium); Pfeiffer, Franz [Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Institut für diagnostische und interventionelle Radiologie, Klinikum rechts der Isar, Technische Universität München, 81675 München (Germany); Institute for Advanced Study, Technische Universität München, 85748 Garching (Germany)
2015-12-15
In the field of biomedical X-ray imaging, novel techniques, such as phase-contrast and dark-field imaging, have the potential to enhance the contrast and provide complementary structural information about a specimen. In this paper, a first prototype of a preclinical X-ray phase-contrast CT scanner based on a Talbot-Lau interferometer is characterized. We present a study of the contrast-to-noise ratios for attenuation and phase-contrast images acquired with the prototype scanner. The shown results are based on a series of projection images and tomographic data sets of a plastic phantom in phase and attenuation-contrast recorded with varying acquisition settings. Subsequently, the signal and noise distribution of different regions in the phantom were determined. We present a novel method for estimation of contrast-to-noise ratios for projection images based on the cylindrical geometry of the phantom. Analytical functions, representing the expected signal in phase and attenuation-contrast for a circular object, are fitted to individual line profiles of the projection data. The free parameter of the fit function is used to estimate the contrast and the goodness of the fit is determined to assess the noise in the respective signal. The results depict the dependence of the contrast-to-noise ratios on the applied source voltages, the number of steps of the phase stepping routine, and the exposure times for an individual step. Moreover, the influence of the number of projection angles on the image quality of CT slices is investigated. Finally, the implications for future imaging purposes with the scanner are discussed.
Contrast-to-noise ratio optimization for a prototype phase-contrast computed tomography scanner.
Müller, Mark; Yaroshenko, Andre; Velroyen, Astrid; Bech, Martin; Tapfer, Arne; Pauwels, Bart; Bruyndonckx, Peter; Sasov, Alexander; Pfeiffer, Franz
2015-12-01
In the field of biomedical X-ray imaging, novel techniques, such as phase-contrast and dark-field imaging, have the potential to enhance the contrast and provide complementary structural information about a specimen. In this paper, a first prototype of a preclinical X-ray phase-contrast CT scanner based on a Talbot-Lau interferometer is characterized. We present a study of the contrast-to-noise ratios for attenuation and phase-contrast images acquired with the prototype scanner. The shown results are based on a series of projection images and tomographic data sets of a plastic phantom in phase and attenuation-contrast recorded with varying acquisition settings. Subsequently, the signal and noise distribution of different regions in the phantom were determined. We present a novel method for estimation of contrast-to-noise ratios for projection images based on the cylindrical geometry of the phantom. Analytical functions, representing the expected signal in phase and attenuation-contrast for a circular object, are fitted to individual line profiles of the projection data. The free parameter of the fit function is used to estimate the contrast and the goodness of the fit is determined to assess the noise in the respective signal. The results depict the dependence of the contrast-to-noise ratios on the applied source voltages, the number of steps of the phase stepping routine, and the exposure times for an individual step. Moreover, the influence of the number of projection angles on the image quality of CT slices is investigated. Finally, the implications for future imaging purposes with the scanner are discussed.
Optimization of urban wastewater treatment plants process with low C/N ratio
Zheng, L.; Xu, G. M.; Chen, J.; Chen, B.; Lv, Z.; Yang, Y. A.
2016-08-01
In southern China, the inflow of water to wastewater treatment plants has a lower concentration of organic matter. This causes treatment plants to face issues in the denitrification and phosphorus removal processes such as deficient carbon sources, high energy consumption, and unstable nitrogen removal. To resolve these issues, we propose the reconstruction of the internal reflux port, improvement of the internal reflux ratio to 200%, the addition of carbon source to anoxic zone, and the addition of phosphorus removal agents in secondary settling tank. The results of study show significantly improved efficiency of nitrogen and phosphorus removal, which ensures the stability of subsequent supply of reused water.
Resource elasticity of offspring survival and the optimal evolution of sex ratios.
Directory of Open Access Journals (Sweden)
Rui-Wu Wang
Full Text Available The fitness of any organisms includes the survival and reproductive rate of adults and the survival of their offspring. Environmental selection pressures might not affect these two aspects of an organism equally. Assuming that an organism first allocates its limited resources to maintain its survival under environmental selection pressure, our model, based on the evolutionarily stable strategy theory, surprisingly shows that the sex ratio is greatly affected by the environmental pressure intensity and by the reproductive resource elasticity of offspring survival. Moreover, the concept of the resource elasticity of offspring survival intrinsically integrates the ecological concepts of K selection and r selection. The model shows that in a species with reproductive strategy K, increased environmental selection pressure will reduce resource allocation to the male function. By contrast, in a species with reproductive strategy r, harsher environmental selection pressure will increase allocation to the male function. The elasticity of offspring survival might vary not only across species, but also across many other factors affecting the same species (e.g., age structure, spatial heterogeneity, which explains sex ratio differences across species or age structures and spatial heterogeneity in the same species.
DEFF Research Database (Denmark)
de Los Milagros Bassani Molinas, Maria; Beer, Christiane; Hesse, F
2014-01-01
Large scale, transient gene expression (TGE) is highly dependent of the physiological status of a cell line. Therefore, intracellular nucleotide pools and ratios were used for identifying and monitoring the optimal status of a suspension cell line used for TGE. The transfection efficiency upon...... polyethyleneimine (PEI)-mediated transient gene delivery into HEK-293 cells cultured in suspension was investigated to understand the effect of different culture and transfection conditions as well as the significance of the culture age and the quality of the cell line used. Based on two different bicistronic model...
Hendricks, F.; der Au, J. Aus; Matylitsky, V. V.
2014-10-01
High average power, high repetition rate femtosecond lasers with μJ pulse energies are increasingly used for material processing applications. The unique advantage of material processing with sub-picosecond lasers is efficient, fast and localized energy deposition, which leads to high ablation efficiency and accuracy in nearly all kinds of solid materials. This work focuses on the machining of high aspect ratio structures in transparent dielectrics, in particular chemically strengthened Xensation™ glass from Schott using multi-pass ablative material removal. For machining of high aspect ratio structures, among others needed for cutting applications, a novel method to determine the best relation between kerf width and number of overscans is presented. The importance of this relation for optimization of the machining throughput will be demonstrated.
Optimization study on pin tip diameter of an impact-pin nozzle at high pressure ratio
Energy Technology Data Exchange (ETDEWEB)
Kumar, C. Palani; Lee, Kwon Hee [FMTRC, Daejoo Machinery Co. Ltd., Daegu (Korea, Republic of); Park, Tae Choon; Cha, Bong Jun [Engine Components Research Team, Korea Aerospace Research Institute, Daejeon (Korea, Republic of); Kim, Heuy Dong [Dept. of Mechanical Engineering, Andong National University, Andong (Korea, Republic of)
2016-09-15
Wet compression system is typically installed in a gas turbine engine to increase the net power output and efficiency. A crucial component of the wet compression system is the nozzle which generates fine water droplets for injection into the compressor. The main objective of present work is to optimize a kind of nozzle called impact-pin spray nozzle and thereby produce better quality droplets. To achieve this, the dynamics occurring in the water jet impinging on the pin tip, the subsequent formation of water sheet, which finally breaks into water droplets, must be studied. In this manuscript, the progress on the numerical studies on impact-pin nozzle are reported. A small computational domain covering the orifice, pin tip and the region where primary atomization occurs is selected for numerical analysis. The governing equations are selected in three dimensional cartesian form and simulations are performed to predict the dynamics of water jet impinging on the pin. Systematic studies were carried out and the results leading to the choice of turbulence model and the effect of pin tip diameter are reported here. Further studies are proposed to show the future directions of the present research work.
Corrêa, Márcia Mara; Thumé, Elaine; De Oliveira, Elizabete Regina Araújo; Tomasi, Elaine
2016-01-01
A systematic review was carried out aiming to collect evidence on the use of the waist-to-height ratio (WHtR) on the elderly population, focusing on validity measures to identify the best anthropometric indicator in assessing obesity associated with non-communicable diseases. The review consisted in a search of papers published on the databases Pubmed, Web of Science, and Lilacs, with no restriction regarding period of publication, using the following combinations: abdominal fat or overweight or obesity and waist-to-height ratio or waist height or waist ht or WHtR or waist to stature ratio or wst stature or WSR or stature and girth. Sixteen papers were selected, most of which with high methodological quality. The receiver-operating characteristic (ROC) curves was the validity measure explored in 13 papers, followed by sensitivity and specificity measures. In all studies, the body mass index (BMI) and waist circumference (WC) received special attention for analysis along with WHtR. Five manuscripts showed evidence of WHtR being the best anthropometric index when used alone, four showed that both WHtR and WC had the best discriminatory power in predicting cardiovascular risk factors compared to the other indices, and two ranked WHtR at the same performance level as waist-to-hip ratio (WHR) and BMI. An association was shown of the obesity assessed by WHtR in predicting risk factors for cardiovascular diseases, metabolic syndrome, and diabetes compared to other anthropometric parameters.
X-ray spectral optimization for mammography applications using signal-to-noise ratio
Tucker, Jonathan Ernest
2000-07-01
A hypotheses that optimum exposure technique factors for mammography can be computed using uncorrected x-ray spectra measured with an inexpensive semiconductor detector is proven. A parametric model is developed, based upon the minimum signal-to-noise ratio required to perceive an object against background, to predict optimum exposure technique factors. Using published molybdenum- and rhodium-target x-ray spectra, the model predicts that aluminum-filtered molybdenum and rhodium spectra are optimum. The model is subsequently used to predict optimum exposure technique factors using uncorrected x- ray spectra from a GE Senographe DMR mammography unit measured with a cadmium zinc telluride detector and multichannel analyzer. The computed optimum exposure technique factors using uncorrected measured spectra and published spectra are comparable. The model is validated using the uncorrected measured spectra and a phantom containing objects mimicking microcalcifications and fibrous tissue structures. Entrance skin exposure and breast dose for aluminum-filtered spectra are well below those produced using currently popular k-edge filtered spectra. Aluminum-filtered spectra should be considered useful because (1)structures associated with breast cancer can be successfully imaged, and (2)the patient receives a greatly reduced dose.
Sica, R J; Haefele, A
2016-02-01
Lidar measurements of the atmospheric water vapor mixing ratio provide an excellent complement to radiosoundings and passive, ground-based remote sensors. Lidars are now routinely used that can make high spatial-temporal resolution measurements of water vapor from the surface to the stratosphere. Many of these systems can operate during the day and night, with operation only limited by clouds thick enough to significantly attenuate the laser beam. To enhance the value of these measurements for weather and climate studies, this paper presents an optimal estimation method (OEM) to retrieve the water vapor mixing ratio, aerosol optical depth profile, Ångstrom exponent, lidar constants, detector dead times, and measurement backgrounds from multichannel vibrational Raman-scatter lidars. The OEM retrieval provides the systematic uncertainties due to the overlap function, calibration factor, air density and Rayleigh-scatter cross sections, in addition to the random uncertainties of the retrieval due to measurement noise. The OEM also gives the vertical resolution of the retrieval as a function of height, as well as the height to which the contribution of the a priori is small. The OEM is applied to measurements made by the Meteoswiss Raman Lidar for Meteorological Observations (RALMO) in the day and night for clear and cloudy conditions. The retrieved water vapor mixing ratio is in excellent agreement with both the traditional lidar retrieval method and coincident radiosoundings.
Institute of Scientific and Technical Information of China (English)
FENG Zhengfu; DONG Chaohua; WANG Linlin; HU Yanjiang; ZHU Wei
2013-01-01
The optimal quantity of dietary lysine (Lys) and arginine (Arg),and the optimal ratio of dietary Lys to Arg for Pacific white shrimp Litopenaeus vannamei were investigated.Coated Lys and Arg were added to a basal diet (37.99％ crude protein and 7.28％ crude lipid) to provide graded levels of Lys and Arg.The experimental diets contained three Lys levels (2.51％,2.11％,and 1.70％ of total diet),and three Arg levels (1.41％,1.80％,and 2.21％ of total diet) and all combinations of these levels were tested.Pacific white shrimp,with a mean weight of 3.62±0.1 g,were randomly distributed in 36 fiberglass tanks with 30 shrimp per tank and reared on the experimental diets for 50 days.After the feeding trial,the growth performance,survival,feed conversion rate (FCR),body composition and protease and lipase activities in the hepatopancreases of the experimental shrimps were determined.The results show that weight gain (WG),specific growth rate (SGR),FCR,body protein,body Lys and Arg content were significantly affected by dietary Lys and Arg (P＜0.05) and improved when dietary Lys and Arg levels were 2.11％-2.51％ and 1.80％-2.21％,respectively.Protease and lipase activities in the hepatopancreases of the shrimps appeared higher when dietary Lys and Arg quantities were 2.11％-2.51％ and 1.80％-2.21％,although the difference was not statistically significant (P＞0.05).Therefore,according to our results,the optimal Lys and Arg quantities in the diet of Pacific white shrimp,L.vannamei,were considered to be 2.11％-2.51％ and 1.80％-2.21％,respectively,and the optimal ratio to be 1:0.88-1:1.05.
Margolis, H S
2015-01-01
A method is presented for analysing over-determined sets of clock frequency comparison data involving standards based on a number of different reference transitions. This least-squares adjustment procedure, which is based on the method used by CODATA to derive a self-consistent set of values for the fundamental physical constants, can be used to derive optimized values for the frequency ratios of all possible pairs of reference transitions. It is demonstrated to reproduce the frequency values recommended by the International Committee for Weights and Measures, when using the same input data used to derive those values. The effects of including more recently published data in the evaluation is discussed and the importance of accounting for correlations between the input data is emphasised.
Directory of Open Access Journals (Sweden)
Ali Gorener
2013-04-01
Full Text Available Location selection problem in banking is an important issue for the commercial success in competitive environment. There is a strategic fit between the location selection decision and overall performance of a new branch. Providing physical service in requested location as well as alternative distribution channels to meet profitable client needs is the current problematic to achieve the competitive advantage over the rivalry in financial system. In this paper, an integrated model has been developed to support in the decision of branch location selection for a new bank branch. Analytic Hierarchy Process (AHP technique has been conducted to prioritize of evaluation criteria, and multi-objective optimization on the basis of ratio analysis (MOORA method has been applied to rank location alternatives of bank branch.
Institute of Scientific and Technical Information of China (English)
祝效华; 石昌帅; 童华
2015-01-01
In order to meet the high temperature environment requirement of deep and superdeep well exploitation, a technology of large length-to-diameter ratio metal stator screw lining meshing with rotor is presented. Based on the elastic-plasticity theory, and under the consideration of the effect of tube size, material mechanical parameters, friction coefficient and loading paths, the external pressure plastic forming mechanical model of metal stator screw lining is established, to study the optimal loading path of metal stator lining tube hydroforming process. The results show that wall thickness reduction of the external pressure tube hydroforming (THF) is about 4%, and three evaluation criteria of metal stator screw lining forming quality are presented: fillet stick mold coefficient, thickness relative error and forming quality coefficient. The smaller the three criteria are, the better the forming quality is. Each indicator has a trend of increase with the loading rate reducing, and the adjustment laws of die arc transition zone equidistance profile curve are acquired for improving tube forming quality. Hence, the research results prove the feasibility of external pressure THF used for processing high-accuracy large length-to-diameter ratio metal stator screw lining, and provide theoretical basis for designing new kind of stator structure which has better performance and longer service life.
Directory of Open Access Journals (Sweden)
Imam Taufik
2013-06-01
Full Text Available Pond productivity can be increased by applied polyculture system in the deep pond. The purpose of this experiment is to examine the optimal ratio between nile tilapia and common carp, in order to increase the productivity. Nine concrete tanks (15 m2 with water depth of 2.2 m and were completed by water inlet, water outlet, and aeration. Both of nile tilapia and common carp with size ranging of 5-8 cm in total length were used. Stock density was 150 ind./m2. The difference ratio of both fish tilapia and carp of fish stocked as a treatment. The fish ratio this experiment were as followed: A 100%; B 80%:20%; C 60%:40%. Fish fed by pellet until at ad libitum. The duration of experiment was 100 days. Parameters such as survival, growth, and productivity were observed every ten days during the experiment period. Water quality parameters were also periodically observed. The results showed that survival of nile tilapia among the treatments were not significantly different (P>0.05 where survival of common carp at B treatment was better than C treatment (P<0.05. The highest of growth of absolute weight (94.86±2.85 g and total length (14.71±1 cm of nile tilapia at B treatment was found (P<0.05 where the best of growth of absolute weight (106.52±10.47 g and total length (11.57±1.78 cm of common carp was also found at B treatment (P<0.05. Biomass productivity at B treatment was the highest compared with A treatment (P<0.05. Combination between polyculture and the deep water pond technology could increase productivity. The polyculture system and the deep water pond technology would be able to keep constant water quality within in the threshold accordance with the regulation for fish culture.
Boulyga, Sergei F; Klötzli, Urs; Stingeder, Gerhard; Prohaska, Thomas
2007-10-15
An inductively coupled plasma mass spectrometer with dynamic reaction cell (ICP-DRC-MS) was optimized for determining (44)Ca/(40)Ca isotope ratios in aqueous solutions with respect to (i) repeatability, (ii) robustness, and (iii) stability. Ammonia as reaction gas allowed both the removal of (40)Ar+ interference on (40)Ca+ and collisional damping of ion density fluctuations of an ion beam extracted from an ICP. The effect of laboratory conditions as well as ICP-DRC-MS parameters such a nebulizer gas flow rate, rf power, lens potential, dwell time, or DRC parameters on precision and mass bias was studied. Precision (calculated using the "unbiased" or "n - 1" method) of a single isotope ratio measurement of a 60 ng g(-1) calcium solution (analysis time of 6 min) is routinely achievable in the range of 0.03-0.05%, which corresponded to the standard error of the mean value (n = 6) of 0.012-0.020%. These experimentally observed RSDs were close to theoretical precision values given by counting statistics. Accuracy of measured isotope ratios was assessed by comparative measurements of the same samples by ICP-DRC-MS and thermal ionization mass spectrometry (TIMS) by using isotope dilution with a (43)Ca-(48)Ca double spike. The analysis time in both cases was 1 h per analysis (10 blocks, each 6 min). The delta(44)Ca values measured by TIMS and ICP-DRC-MS with double-spike calibration in two samples (Ca ICP standard solution and digested NIST 1486 bone meal) coincided within the obtained precision. Although the applied isotope dilution with (43)Ca-(48)Ca double-spike compensates for time-dependent deviations of mass bias and allows achieving accurate results, this approach makes it necessary to measure an additional isotope pair, reducing the overall analysis time per isotope or increasing the total analysis time. Further development of external calibration by using a bracketing method would allow a wider use of ICP-DRC-MS for routine calcium isotopic measurements, but it
Solevåg, Anne Lee; Schmölzer, Georg M.
2017-01-01
Cardiopulmonary resuscitation (CPR) duration until return of spontaneous circulation (ROSC) influences survival and neurologic outcomes after delivery room (DR) CPR. High quality chest compressions (CC) improve cerebral and myocardial perfusion. Improved myocardial perfusion increases the likelihood of a faster ROSC. Thus, optimizing CC quality may improve outcomes both by preserving cerebral blood flow during CPR and by reducing the recovery time. CC quality is determined by rate, CC to ventilation (C:V) ratio, and applied force, which are influenced by the CC provider. Thus, provider performance should be taken into account. Neonatal resuscitation guidelines recommend a 3:1 C:V ratio. CCs should be delivered at a rate of 90/min synchronized with ventilations at a rate of 30/min to achieve a total of 120 events/min. Despite a lack of scientific evidence supporting this, the investigation of alternative CC interventions in human neonates is ethically challenging. Also, the infrequent occurrence of extensive CPR measures in the DR make randomized controlled trials difficult to perform. Thus, many biomechanical aspects of CC have been investigated in animal and manikin models. Despite mathematical and physiological rationales that higher rates and uninterrupted CC improve CPR hemodynamics, studies indicate that provider fatigue is more pronounced when CC are performed continuously compared to when a pause is inserted after every third CC as currently recommended. A higher rate (e.g., 120/min) is also more fatiguing, which affects CC quality. In post-transitional piglets with asphyxia-induced cardiac arrest, there was no benefit of performing continuous CC at a rate of 90/min. Not only rate but duty cycle, i.e., the duration of CC/total cycle time, is a known determinant of CC effectiveness. However, duty cycle cannot be controlled with manual CC. Mechanical/automated CC in neonatal CPR has not been explored, and feedback systems are under-investigated in this
Karino, Naoki; Shiba, Takashi; Yokoyama, Ryohei; Ito, Koichi
In planning an air conditioning system, supply water and air temperatures are important factors from the viewpoint of energy saving and cost reduction. For example, lower temperature supply water and air for space cooling reduce the coefficient of performance of a refrigeration machine, and increase the thickness of heat insulation material. However, they enable larger temperature differences, and reduce equipment sizes and power demand. It is also an important subject to evaluate the effect of the supply water and air temperatures on energy saving and cost reduction on the annual basis by considering not only cooling but also heating loads. The purposes of this paper are to propose an optimal planning method for an air conditioning system with large temperature difference, and to analyze the effect of supply water and air temperatures on the long-term economics through a numerical study for an office building. As a result, it is shown that the proposed method effectively determines supply water and air temperatures, and the influence of the cooling to heating load ratio on the long-term economics is clarified.
Energy Technology Data Exchange (ETDEWEB)
Garzillo, Valerio; Grigutis, Robertas [Dipartimento di Scienza e Alta Tecnologia, University of Insubria, Via Valleggio 11, I-22100 Como (Italy); Jukna, Vytautas [Centre de Physique Theorique, CNRS, Ecole Polytechnique, Université Paris-Saclay, F-91128 Palaiseau (France); LOA, ENSTA-ParisTech, CNRS, Ecole Polytechnique, Université Paris Saclay, F-91762 Palaiseau (France); Couairon, Arnaud [Centre de Physique Theorique, CNRS, Ecole Polytechnique, Université Paris-Saclay, F-91128 Palaiseau (France); Di Trapani, Paolo [Dipartimento di Scienza e Alta Tecnologia, University of Insubria and CNISM UdR Como, Via Valleggio 11, I-22100 Como (Italy); Jedrkiewicz, Ottavia, E-mail: ottavia.jedrkiewicz@ifn.cnr.it [Istituto di Fotonica e Nanotecnologie, CNR and CNISM UdR Como, Via Valleggio 11, I-22100 Como (Italy)
2016-07-07
We investigate the generation of high aspect ratio microstructures across 0.7 mm thick glass by means of single shot Bessel beam laser direct writing. We study the effect on the photoinscription of the cone angle, as well as of the energy and duration of the ultrashort laser pulse. The aim of the study is to optimize the parameters for the writing of a regular microstructure due to index modification along the whole sample thickness. By using a spectrally resolved single pulse transmission diagnostics at the output surface of the glass, we correlate the single shot material modification with observations of the absorption in different portions of the retrieved spectra, and with the absence or presence of spectral modulation. Numerical simulations of the evolution of the Bessel pulse intensity and of the energy deposition inside the sample help us interpret the experimental results that suggest to use picosecond pulses for an efficient and more regular energy deposition. Picosecond pulses take advantage of nonlinear plasma absorption and avoid temporal dynamics effects which can compromise the stationarity of the Bessel beam propagation.
Garzillo, Valerio; Jukna, Vytautas; Couairon, Arnaud; Grigutis, Robertas; Di Trapani, Paolo; Jedrkiewicz, Ottavia
2016-07-01
We investigate the generation of high aspect ratio microstructures across 0.7 mm thick glass by means of single shot Bessel beam laser direct writing. We study the effect on the photoinscription of the cone angle, as well as of the energy and duration of the ultrashort laser pulse. The aim of the study is to optimize the parameters for the writing of a regular microstructure due to index modification along the whole sample thickness. By using a spectrally resolved single pulse transmission diagnostics at the output surface of the glass, we correlate the single shot material modification with observations of the absorption in different portions of the retrieved spectra, and with the absence or presence of spectral modulation. Numerical simulations of the evolution of the Bessel pulse intensity and of the energy deposition inside the sample help us interpret the experimental results that suggest to use picosecond pulses for an efficient and more regular energy deposition. Picosecond pulses take advantage of nonlinear plasma absorption and avoid temporal dynamics effects which can compromise the stationarity of the Bessel beam propagation.
Directory of Open Access Journals (Sweden)
Al-Attas Omar S
2012-08-01
Full Text Available Abstract Background Sagittal abdominal diameter (SAD is a novel anthropometric measure hypothesized to be a surrogate measure of visceral abdominal obesity in adults. This study aims to determine whether SAD is superior to other anthropometric measures such as body mass index (BMI and waist to hip ratio (WHR in terms of association to cardiometabolic risk and circulating adipocytokine concentrations in a cohort of Saudi children and adolescents. Methods A total of 948 (495 boys and 453 girls apparently healthy children with varying BMI, aged 10–17 years, were included in this cross sectional study. Fasting glucose, lipid profile, leptin, adiponectin, resistin, insulin, TNF-α and aPAI-1 were measured in serum and HOMA-IR was calculated. MetS components were defined according to the International Diabetes Federation (IDF criteria. Results BMI was superior to SAD as well as WHR, and had the highest number of significant associations to MetS components and adipocytokines even after adjustment for age and gender, including blood pressure, lipids, glucose and leptin. Conclusion In conclusion, while SAD is significantly associated with components of MetS among children and adolescents, it is not superior to BMI. The use of SAD therefore may not be practical for use in the pediatric clinical setting. Follow-up studies are needed to determine whether SAD has clinical significance in terms of harder outcomes such as predicting diabetes mellitus or cardiovascular diseases.
Al-Attas, Omar S; Al-Daghri, Nasser M; Alokail, Majed S; Alkharfy, Khalid M; Draz, Hossam; Yakout, Sobhy; Sabico, Shaun; Chrousos, George
2012-08-07
Sagittal abdominal diameter (SAD) is a novel anthropometric measure hypothesized to be a surrogate measure of visceral abdominal obesity in adults. This study aims to determine whether SAD is superior to other anthropometric measures such as body mass index (BMI) and waist to hip ratio (WHR) in terms of association to cardiometabolic risk and circulating adipocytokine concentrations in a cohort of Saudi children and adolescents. A total of 948 (495 boys and 453 girls) apparently healthy children with varying BMI, aged 10-17 years, were included in this cross sectional study. Fasting glucose, lipid profile, leptin, adiponectin, resistin, insulin, TNF-α and aPAI-1 were measured in serum and HOMA-IR was calculated. MetS components were defined according to the International Diabetes Federation (IDF) criteria. BMI was superior to SAD as well as WHR, and had the highest number of significant associations to MetS components and adipocytokines even after adjustment for age and gender, including blood pressure, lipids, glucose and leptin. In conclusion, while SAD is significantly associated with components of MetS among children and adolescents, it is not superior to BMI. The use of SAD therefore may not be practical for use in the pediatric clinical setting. Follow-up studies are needed to determine whether SAD has clinical significance in terms of harder outcomes such as predicting diabetes mellitus or cardiovascular diseases.
Institute of Scientific and Technical Information of China (English)
WEI-PING JIA; JUN-XI LU; KUN-SAN XIANG; YU-QIAN BAO; HUI-JUAN LU; LEI CHEN
2003-01-01
To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR were assessed in 690 Chinese adults (305 men and 385women) and compared with magnetic resonance imaging (MRI) measurements of abdominal visceral adipose tissue (VA). Receiver operating characteristic (ROC) curves were generated and used to determine the threshold point for each anthropometric parameter. Results 1) MRI showed that 61.7% of overweight/obese individuals (BMI≥25 kg/m2) and 14.2% of normal weight (BMI＜25kg/m2) individuals had abdominal visceral obesity (VA≥ 100 cm2). 2) VA was positively correlated with each anthropometric variable, of which WC showed the highest correlation (r=0.73-0.77,P＜0.001 ). 3) The best cut-off points for assessing abdominal visceral obesity were as followed: BMI of 26 kg/m2, WC of 90 cm, and WHR of 0.93, with WC being the most sensitive and specific factor. 4)Among subjects with BMI≥28 kg/m2 or WC≥95 cm, 95% of men and 90% of women appeared to have abdominal visceral obesity. Conclusion Measurements of BMI, WC, and WHR can be used in the prediction of abdominal visceral obesity, of which WC was the one with better accuracy.
Waist-to-height ratio is the best anthropometric predictor of hypertension
Caminha, Tainá C.S.; Ferreira, Haroldo S.; Costa, Narithania S.; Nakano, Ricardo P.; Carvalho, Renata Elyonara S.; Xavier, Antônio F.S.; Assunção, Monica L.
2017-01-01
Abstract The WHO recommends the use of some anthropometric parameters as a screening resource for individuals under cardiometabolic risk. However, in the validation of these indicators, Brazilian women were not included. These women have different anthropometric profile compared to women who integrated the samples of the validation studies. We aimed to verify the accuracy of anthropometric indicators as a resource for the screening of women with hypertension. A cross-sectional study, with a probability sample of 3143 women (20–49 years) from the state of Alagoas (northeast of Brazil), was carried out. Hypertension was identified by systolic blood pressure (SBP) ≥140 mm Hg and/or diastolic BP ≥90 mm Hg and/or regular use of antihypertensive drugs. The anthropometric indicators analyzed were BMI, waist circumference, waist-to-hip ratio, waist-to-height ratio (WHtR), body fat percentage, and conicity index. The accuracy definition of the indicators and the identification of best cut-off points were carried out on the basis of ROC curve analysis and Youden index, respectively. The prevalence of hypertension was 21.8%. All indicators used in hypertension identification had area under the ROC curve (AUC) >0.5. The WHtR with cut-off point of 0.54 was the best performance indicator (AUC = 0.72; P < 0.05; sensitivity = 67%, specificity = 66%). The WHtR with cut-off point of 0.54 has constituted the most accurate indicator in the screening of women with hypertension. In the absence of specific studies and considering the largest ethnic proximity and environmental/epidemiological similarity, the findings now obtained can be extended to women of other Brazilian states, especially those in the Northeastern region. PMID:28079826
Directory of Open Access Journals (Sweden)
G. Magudeeswaran
2014-09-01
Full Text Available The activated TIG (ATIG welding process mainly focuses on increasing the depth of penetration and the reduction in the width of weld bead has not been paid much attention. The shape of a weld in terms of its width-to-depth ratio known as aspect ratio has a marked influence on its solidification cracking tendency. The major influencing ATIG welding parameters, such as electrode gap, travel speed, current and voltage, that aid in controlling the aspect ratio of DSS joints, must be optimized to obtain desirable aspect ratio for DSS joints. Hence in this study, the above parameters of ATIG welding for aspect ratio of ASTM/UNS S32205 DSS welds are optimized by using Taguchi orthogonal array (OA experimental design and other statistical tools such as Analysis of Variance (ANOVA and Pooled ANOVA techniques. The optimum process parameters are found to be 1 mm electrode gap, 130 mm/min travel speed, 140 A current and 12 V voltage. The aspect ratio and the ferrite content for the DSS joints fabricated using the optimized ATIG parameters are found to be well within the acceptable range and there is no macroscopically evident solidification cracking.
Institute of Scientific and Technical Information of China (English)
G. MAGUDEESWARAN; Sreehari R. NAIR; L. SUNDAR; N. HARIKANNAN
2014-01-01
The activated TIG (ATIG) welding process mainly focuses on increasing the depth of penetration and the reduction in the width of weld bead has not been paid much attention. The shape of a weld in terms of its width-to-depth ratio known as aspect ratio has a marked influence on its solidification cracking tendency. The major influencing ATIG welding parameters, such as electrode gap, travel speed, current and voltage, that aid in controlling the aspect ratio of DSS joints, must be optimized to obtain desirable aspect ratio for DSS joints. Hence in this study, the above parameters of ATIG welding for aspect ratio of ASTM/UNS S32205 DSS welds are optimized by using Taguchi orthogonal array (OA) experimental design and other statistical tools such as Analysis of Variance (ANOVA) and Pooled ANOVA techniques. The optimum process parameters are found to be 1 mm electrode gap, 130 mm/min travel speed, 140 A current and 12 V voltage. The aspect ratio and the ferrite content for the DSS joints fabricated using the optimized ATIG parameters are found to be well within the acceptable range and there is no macroscopically evident solidification cracking.
G. Magudeeswaran; Sreehari R. Nair; Sundar, L.; N. Harikannan
2014-01-01
The activated TIG (ATIG) welding process mainly focuses on increasing the depth of penetration and the reduction in the width of weld bead has not been paid much attention. The shape of a weld in terms of its width-to-depth ratio known as aspect ratio has a marked influence on its solidification cracking tendency. The major influencing ATIG welding parameters, such as electrode gap, travel speed, current and voltage, that aid in controlling the aspect ratio of DSS joints, must be optimized to...
Directory of Open Access Journals (Sweden)
Banani Basu
2010-05-01
Full Text Available In this paper, we propose a technique based on two evolutionary algorithms simulated annealing and particle swarm optimization to design a linear array of half wavelength long parallel dipole antennas that will generate a pencil beam in the horizontal plane with minimum standing wave ratio (SWR and fixed side lobe level (SLL. Dynamic range ratio of current amplitude distribution is kept at a fixed value. Two different methods have been proposed withdifferent inter-element spacing but with same current amplitude distribution. First one uses a fixed geometry and optimizes the excitation distribution on it. In the second case further reduction of SWR is done via optimization of interelement spacing while keeping the amplitude distribution same as before. Coupling effect between the elements is analyzed using induced EMF method and minimized interms of SWR. Numerical results obtained from SA are validated by comparing with results obtained using PSO.
Talukder, Srijeeta; Sen, Shrabani; Shandilya, Bhavesh K.; Sharma, Rahul; Chaudhury, Pinaki; Adhikari, Satrajit
2015-10-01
We propose a strategy of using a stochastic optimization technique, namely, simulated annealing to design optimum laser pulses (both IR and UV) to achieve greater fluxes along the two dissociating channels (O18 + O16O16 and O16 + O16O18) in O16O16O18 molecule. We show that the integrated fluxes obtained along the targeted dissociating channel is larger with the optimized pulse than with the unoptimized one. The flux ratios are also more impressive with the optimized pulse than with the unoptimized one. We also look at the evolution contours of the wavefunctions along the two channels with time after the actions of both the IR and UV pulses and compare the profiles for unoptimized (initial) and optimized fields for better understanding the results that we achieve. We also report the pulse parameters obtained as well as the final shapes they take.
Talukder, Srijeeta; Sen, Shrabani; Shandilya, Bhavesh K; Sharma, Rahul; Chaudhury, Pinaki; Adhikari, Satrajit
2015-10-14
We propose a strategy of using a stochastic optimization technique, namely, simulated annealing to design optimum laser pulses (both IR and UV) to achieve greater fluxes along the two dissociating channels (O(18) + O(16)O(16) and O(16) + O(16)O(18)) in O(16)O(16)O(18) molecule. We show that the integrated fluxes obtained along the targeted dissociating channel is larger with the optimized pulse than with the unoptimized one. The flux ratios are also more impressive with the optimized pulse than with the unoptimized one. We also look at the evolution contours of the wavefunctions along the two channels with time after the actions of both the IR and UV pulses and compare the profiles for unoptimized (initial) and optimized fields for better understanding the results that we achieve. We also report the pulse parameters obtained as well as the final shapes they take.
... overweight. Your provider may also take your waist circumference and waist-to-hip ratio into consideration. Your BMI alone can't predict your health risk, but most experts say that a BMI greater ...
Energy Technology Data Exchange (ETDEWEB)
Sri Bala Kameswari, K.; Chitra Kalyanaraman,; Porselvam, S. [Central Leather Research Institute (CLRI), Environmental Technology Division, Chennai (India); Thanasekaran, K. [Anna University, Centre for Environmental Studies, Chennai (India)
2012-04-15
The inoculum to substrate (I/S) ratio is an important factor which influences the anaerobic digestion process. In this study, the effect of different I/S ratios on the performance of co-digestion of fleshings along with mixture of sludge generated during treatment of tannery wastewater was investigated. The parameters studied were biogas generation, volatile solids reduction, volatile fatty acid (VFA) production, and the stability of the digestion process based on VFA to alkalinity ratio was evaluated for various I/S ratios. Economical significance of I/S ratio as related to the volume of the anaerobic digester and the potential benefit of bio-energy generated are discussed in detail. (orig.)
Institute of Scientific and Technical Information of China (English)
2008-01-01
Most of the previous researches about portfolio analysis focus on short-selling. In fact, no short-selling is also important because short-selling is not allowed in stock markets of some coun-tries. This paper gives the suffcient and necessary conditions and proposes an optimal algorithm for Markowitz’s mean-variance models and Sharpe’s ratio with no short-selling. The optimal algorithm makes it easier to obtain the effcient frontiers with no short-selling.
Global Optimization Algorithm for Nonlinear Sum of Ratios Problems%非线性比式和问题的全局优化算法
Institute of Scientific and Technical Information of China (English)
焦红伟; 郭运瑞; 陈永强
2008-01-01
In this paper,a global optimization algorithm is proposed for nonlinear sum of ratios problem(P).The algorithm works by globally solving problem(P1)that is equivalent to problem(P),by utilizing linearization technique a linear relaxation programming of the(P1)is then obtained.The proposed algorithm is convergent to the global minimum of(P1)through the successive refinement of linear relaxation of the feasible region of objective function and solutions of a series of linear relaxation programming.Numerical results indicate that the proposed algorithm is feasible and can be used to globally solve nonlinear sum of ratios problems(P).
Visual cues to female physical attractiveness.
Tovée, M.J.; Maisey, D S; Emery, J. L.; Cornelissen, P L
1999-01-01
Evolutionary psychology suggests that a woman's sexual attractiveness is based on cues of health and reproductive potential. In recent years, research has focused on the ratio of the width of the waist to the width of the hips (the waist-to-hip ratio (WHR). A low WHR (i.e. a curvaceous body) is believed to correspond to the optimal fat distribution for high fertility, and so this shape should be highly attractive. In this paper we present evidence that weight scaled for height (the body mass ...
Calderone, Luigi; Pinola, Licia; Varoli, Vincenzo
1992-04-01
The paper describes an analytical procedure to optimize the feed-forward compensation for any PWM dc/dc converters. The aims of achieving zero dc audiosusceptibility was found to be possible for the buck, buck-boost, Cuk, and SEPIC cells; for the boost converter, however, only nonoptimal compensation is feasible. Rules for the design of PWM controllers and procedures for the evaluation of the hardware-introduced errors are discussed. A PWM controller implementing the optimal feed-forward compensation for buck-boost, Cuk, and SEPIC cells is described and fully experimentally characterized.
Directory of Open Access Journals (Sweden)
Ali Eliassi
2013-01-01
Full Text Available In this study the effects of some different factors on ceria (CeO2 catalytic activity for ethanol steam reforming (ESR to produce high H2/CO ratio were investigated. The considered factors were sonication time in three durations (0, 15 and 30 minutes, calcination temperature at three temperatures (500, 650 and 800°C, mole ratio of H2O/ethanol in three ratios (3, 5 and 8 and reactor temperature at three temperatures (300, 350 and 400°C. The Taguchi L9 experimental design method was used to investigate the effect of these parameters on maximization of H2/CO. To identify the catalyst characteristics XRD, SEM, EDS, BET and TGA analysis were done. It was established that a face centered cubic crystal forms of nano particles of CeO2 were formed. Also the obtained results showed that by increasing calcination temperature or reducing the sonication time, the nano particle size was increased. The reactor tests showed that the optimum conditions for maximization of H2/CO ratio were: sonication time zero, calcination temperature 800°C, H2O/ethanol ratio 3 and reactor temperature 300°C. The mole percent of H2 and CO in these conditions were 64.46 and 0.011%, respectively.
CSIR Research Space (South Africa)
Raju, M
2011-11-01
Full Text Available and optimization of core sampling procedure for carbon isotope analysis in eucalyptus and variation in carbon isotope ratios across species and growth conditions Mohan Raju, B#; Nuveshen Naidoo*; Sheshshaayee, M. S; Verryn, S. D*; Kamalkannan, R^; Bindumadhava... isotope analysis in Eucalyptus. Methods Expt 1: * Cores were taken from periphery to pith in 5 year old trees of Eucalyptus * Five half sib families of Eucalyptus grandis & E. urophylla were used ? Cores were further subdivided into 5 fragments...
Lapert, M; Assémat, E; Glaser, S J; Sugny, D
2015-01-28
We show to which extent the signal to noise ratio per unit time of a spin 1/2 particle can be maximized. We consider a cyclic repetition of experiments made of a measurement followed by a radio-frequency magnetic field excitation of the system, in the case of unbounded amplitude. In the periodic regime, the objective of the control problem is to design the initial state of the system and the pulse sequence which leads to the best signal to noise performance. We focus on two specific issues relevant in nuclear magnetic resonance, the crusher gradient and the radiation damping cases. Optimal control techniques are used to solve this non-standard control problem. We discuss the optimality of the Ernst angle solution, which is commonly applied in spectroscopic and medical imaging applications. In the radiation damping situation, we show that in some cases, the optimal solution differs from the Ernst one.
Energy Technology Data Exchange (ETDEWEB)
Lapert, M.; Glaser, S. J. [Department of Chemistry, Technische Universität München, Lichtenbergstrasse 4, D-85747 Garching (Germany); Assémat, E. [Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université de Bourgogne, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex (France); Department of Chemical Physics, Weizmann Institute of Science, 76100 Rehovot (Israel); Sugny, D., E-mail: dominique.sugny@u-bourgogne.fr [Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université de Bourgogne, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex (France)
2015-01-28
We show to which extent the signal to noise ratio per unit time of a spin 1/2 particle can be maximized. We consider a cyclic repetition of experiments made of a measurement followed by a radio-frequency magnetic field excitation of the system, in the case of unbounded amplitude. In the periodic regime, the objective of the control problem is to design the initial state of the system and the pulse sequence which leads to the best signal to noise performance. We focus on two specific issues relevant in nuclear magnetic resonance, the crusher gradient and the radiation damping cases. Optimal control techniques are used to solve this non-standard control problem. We discuss the optimality of the Ernst angle solution, which is commonly applied in spectroscopic and medical imaging applications. In the radiation damping situation, we show that in some cases, the optimal solution differs from the Ernst one.
Institute of Scientific and Technical Information of China (English)
井源; 董砚虎; 韩婷; 张磊; 王娜; 朱娅梅; 徐美华
2012-01-01
Objective To evaluate the relationship between waist to stature ratio (WSR) and hypertension,diabetes,dyslipidemia in Qingdao. Methods Data were collected from a 2001 - 2007 Qingdao area diabetes survey,population-based cross-sectional study,and 30 712 Chinese adults aged ＞ 18 years old were enrolled.Correlation analysis of BMI,WSR,hip circumference,waist circumference,waist to hip ratio (WHR) with blood glucose,blood pressure,blood lipid were conducted.ROC curve analysis in diabetes,bypertension,dyslipidemia and multivariate logistic regression analysis were also conducted.Results Anthropometric indicators were related with hypertension,diabetes and dyslipidemia in both men and women.Comparing with other anthropometric indicators,WSR was found to have the largest area under the ROC curve and the best cut-off point of WSR was 0.52.Multivariate logistic regression analysis showed that, after controlling age, disease history, physical activity, sex, the diabetes hypertension and dyslipidemia risk OR of WSR≥0.52 were largest.Conclusions Anthropometric indicators intimately related with cardiovascular risk factors in Qingdao region,and may predict and evaluate the risk of cardiovascular disease.WSR may be the best index for predicting cardiovascular risk factors in Qingdao area.The optimal WSR cut off point for identifying cardiovascular risk factors clustering is 0.52.%目的 探讨和评价青岛地区人群腰围身高比值(WSR)与高血压、糖尿病、脂代谢异常等心血管疾病危险因素的关系.方法 选取青岛地区糖尿病流行病学调查数据库中资料完整的汉族成年人共30 712例,分析BMI、腰围、WSR、腰臀比(WHR)和臀围与血糖、血压、血脂的相关关系；ROC曲线分析比较5个指标对糖尿病、高血压和脂代谢异常的预测价值并判断最佳切点；多因素logistic逐步回归分析比较5个指标对高血压、糖尿病、脂代谢异常风险的预测价值.结果 (1)各人体测量学指
Directory of Open Access Journals (Sweden)
Yongxiu He
2014-04-01
Full Text Available In Beijing, China, the rational consumption of energy is affected by the insufficient linkage mechanism of the energy pricing system, the unreasonable price ratio and other issues. This paper combines the characteristics of Beijing’s energy market, putting forward the society-economy equilibrium indicator R maximization taking into consideration the mitigation cost to determine a reasonable price ratio range. Based on the computable general equilibrium (CGE model, and dividing four kinds of energy sources into three groups, the impact of price fluctuations of electricity and natural gas on the Gross Domestic Product (GDP, Consumer Price Index (CPI, energy consumption and CO2 and SO2 emissions can be simulated for various scenarios. On this basis, the integrated effects of electricity and natural gas price shocks on the Beijing economy and environment can be calculated. The results show that relative to the coal prices, the electricity and natural gas prices in Beijing are currently below reasonable levels; the solution to these unreasonable energy price ratios should begin by improving the energy pricing mechanism, through means such as the establishment of a sound dynamic adjustment mechanism between regulated prices and market prices. This provides a new idea for exploring the rationality of energy price ratios in imperfect competitive energy markets.
Guo, Xiao-Long; Lu, Xi-Li; Dong, De-Li; Sun, Zhi-Jie
2014-11-01
Poly(glycerol-sebacate) (PGS) is an elastomeric biodegradable polyester. Our previous series of studies have showed that PGS has good biocompatibility. In view of the potential use of PGS in bioengineering, we attempt to characterize the PGS polymer with different ratio of glycerol and sebacic acid, and the cell adhesion and growth on these polymers. PGSs with different proportion of glycerol and sebacic acid were synthesized by polycondensation reaction. The microstructure of the series PGSs were characterized by infrared spectroscopy and X-ray diffraction analysis (XRD). Results showed that, with the increase of the ratio of sebacic acid in PGS from 1:0.8, 1:1, to 1:1.2 (ratio of glycerol to sebacic acid), the main diffraction peak in XRD, the sol content and gel swelling increased but then decreased, suggesting that the degree of crosslinking and the inherent degree of order of the series PGS increased and then decreased. With the increase of sebacic acid proportion, water absorption increased and then decreased, and the water absorption ranged from 9.62% to 10.66%. The mass loss of the series of samples in degradation experiments ranged from 24.63% to 40.06% on the 32nd day of degradation. Cell culture data suggested that the polymer with the ratio of 1:0.8 for glycerol and sebacate was suitable for cell adhesion and growth. In conclusion, PGS can be used as the cell culture matrix by modifying the composition ratio of glycerol and sebacic acid to improve the properties of cell adhesion and growth.
Directory of Open Access Journals (Sweden)
Yamada Hiroaki
2011-11-01
Full Text Available The performance of an electrical generator using bio-fuel and gasoline blends of different composition as fuel in a single cylinder engine is presented. The effect of an optimized blend ratio of bio-fuel with gasoline on engine performance improvement and thereby on the electrical generator output is studied. Bio-fuels such as ethanol, butanol and methanol are blended with gasoline in different proportions and evaluated for performance. The effects of different bio-fuel/gasoline blending ratios are compared experimentally with that of the gasoline alone using the output power developed by the electric generator as the evaluation parameter. With a composition of 10% ethanol–gasoline, the engine performance is increased up to 6% and with a blending ratio of 20% butanol–gasoline the performance is increased up to 8% compared to the use of 100% gasoline. The investigations are performed on a portable generator used in palm tree harvesting applications.
Energy Technology Data Exchange (ETDEWEB)
Almuallim, H. [King Fahd Univ. of Petroleum & Minerals, Dhahran (Saudi Arabia); Akiba, Yasuhiro; Kaneda, Shigeo [NTT Communication Science Labs., Kanagawa (Japan)
1996-12-31
Given a set of training examples S and a tree-structured attribute x, the goal in this work is to find a multiple-split test defined on x that maximizes Quinlan`s gain-ratio measure. The number of possible such multiple-split tests grows exponentially in the size of the hierarchy associated with the attribute. It is, therefore, impractical to enumerate and evaluate all these tests in order to choose the best one. We introduce an efficient algorithm for solving this problem that guarantees maximizing the gain-ratio over all possible tests. For a training set of m examples and an attribute hierarchy of height d, our algorithm runs in time proportional to dm, which makes it efficient enough for practical use.
Directory of Open Access Journals (Sweden)
YOGENDRA TYAGI
2012-08-01
Full Text Available In this paper the drilling of mild steel with the help of CNC drilling machining operation with tool use high speed steel by applying taguchi methodology has been reported. The signal-to-noise ratio applied to find optimum process parameter for CNC drilling machining .A L9 orthogonal array and analysis of variance(ANOVA are applied to study the performance characteristics of machining parameter (spindle speed, feed, depth with consideration of good surface finish as well as high material removal rate(MRR .Surfacefinishing is one of the prime requirements of customers of machining parts .Results obtained by taguchi method and signal-to-noise ratio match closely with (ANOVA and the feed is most effective factor for MRR. And spindle speed is the most effective factor for surface roughness. Multiple regression equation are formulated forestimating predicted value surface roughness and material removal rate
Hambali, Nor Azura Malini A; Mahdi, Mohd Adzir; Al-Mansoori, Mohammed Hayder; Saripan, M Iqbal; Abas, Ahmad Fauzi
2009-09-20
The operation of a single-wavelength Brillouin-erbium fiber laser (BEFL) system with a Brillouin pump preamplified technique for different output coupling ratios in a ring cavity is experimentally demonstrated. The characteristics of Brillouin Stokes power and tunability were investigated in this research. The efficiency of the BEFL operation was obtained at an optimum output coupling ratio of 95%. By fixing the Brillouin pump wavelength at 1550 nm while its power was set at 1.6 mW and the 1480 pump power was set to its maximum value of 135 mW, the Brillioun Stokes power was found to be 28.7 mW. The Stokes signal can be tuned within a range of 60 nm from 1520 to 1580 nm without appearances of the self-lasing cavity modes in the laser system.
Mohammadi, Bahareh; Tammari, Esmail; Fakhri, Sajad; Bahrami, Gholamreza
2013-06-01
Topiramate is an antiepileptic agent, which is structurally different from the other anticonvulsants. The drug has no UV-Vis absorption or emits fluorescence. Thus for its analysis using high performance liquid chromatography (HPLC) with conventional UV or fluorescence detectors, the drug should be derivatized with a suitable reagent. In previous study using fluorenylmethyl chloroformate (FMOC-Cl) and HPLC coupled with fluorescence detector, we reported an analytical method for derivatization and analysis of the drug in human serum. In this method, several factors including time and temperature of the reaction, pH and concentration of the used buffer, ratio of organic phase in the medium and removal of the reagent excess by glycine should be optimized to obtain maximum yield of the product. In HPLC coupled with fluorescence detector, there is not any signal from intact topiramate and only the final product (FMOC-topiramate) is appeared. Thus to optimize the reaction conditions for obtaining the highest derived yield, intensity of the final product peak is considered as a criteria for progression of the reaction. In LC-MS/MS system however, both free and reacted topiramate are visible in observed spectra. In the present study reaction of the drug with FMOC-Cl was re-optimized using LC-MS/MS technique on the basis of reacted/free topiramate ratio as the new and more accurate index. The results showed that, ratio of organic/aqueous phase has a dominant effect on the reaction, the most efficient temperature is 70°C and the reaction is reversed following addition of the glycine.
Shen, Tie; Rui, Bin; Zhou, Hong; Zhang, Ximing; Yi, Yin; Wen, Han; Zheng, Haoran; Wu, Jihui; Shi, Yunyu
2013-01-27
The ability of a microorganism to adapt to changes in the environment, such as in nutrient or oxygen availability, is essential for its competitive fitness and survival. The cellular objective and the strategy of the metabolic response to an extreme environment are therefore of tremendous interest and, thus, have been increasingly explored. However, the cellular objective of the complex regulatory structure of the metabolic changes has not yet been fully elucidated and more details regarding the quantitative behaviour of the metabolic flux redistribution are required to understand the systems-wide biological significance of this response. In this study, the intracellular metabolic flux ratios involved in the central carbon metabolism were determined by fractional (13)C-labeling and metabolic flux ratio analysis (MetaFoR) of the wild-type E. coli strain JM101 at an oxidative environment in a chemostat. We observed a significant increase in the flux through phosphoenolpyruvate carboxykinase (PEPCK), phosphoenolpyruvate carboxylase (PEPC), malic enzyme (MEZ) and serine hydroxymethyltransferase (SHMT). We applied an ε-constraint based multi-objective optimization to investigate the trade-off relationships between the biomass yield and the generation of reductive power using the in silico iJR904 genome-scale model of E. coli K-12. The theoretical metabolic redistribution supports that the trans-hydrogenase pathway should not play a direct role in the defence mounted by E. coli against oxidative stress. The agreement between the measured ratio and the theoretical redistribution established the significance of NADPH synthesis as the goal of the metabolic reprogramming that occurs in response to oxidative stress. Our work presents a framework that combines metabolic flux ratio analysis and multi-objective optimization to investigate the metabolic trade-offs that occur under varied environmental conditions. Our results led to the proposal that the metabolic response of E
Loginova, N. A.; Grigor'ev, S. V.; Lapin, E. E.; Pogorelov, S. I.; Ryzhenkov, A. V.
2016-05-01
Fast-mounted heat-insulating constructions based on foamed synthetic rubbers, polyethylene, and polyurethane are characterized by a thermostability up to 150°C and emit toxic substances when burnt. However, there is a need for heat insulation of surfaces with higher coolant temperatures, such as pipelines, equipment of nuclear and thermal power plants, and heating systems with remote heat sources. One of the most promising types of heat insulation materials for creation of fast-mounted heat insulation constructions is the syntactic foams or thin-film multilayer heat-insulating coatings (TFMHIC), which are created using hollow microspheres and various types of binders. The formation of TFMHIC on the heat-insulating surface is carried out mostly by means of spraying methods that have well proven themselves at coating on flat and cylindrical surfaces of large area, but they turned out ineffective for cylindrical surfaces with a diameter of 300 mm and less, since they are characterized by a large degree of carryover of composite material. This article analyzed the binders and microspheres promising to create the fast-mounted heat-insulating constructions based on TFMHIC with high thermostability. Based on the analysis, a conclusion is drawn that organicsilicon binding and glass microspheres are promising for use in the heat-insulating constructions with thermostability up to 300°C. The results of experimental research are given that point to the possibility of predicting the optimal composition of heat-insulating material characterized by a high degree of filling with microspheres with maintaining the mechanical strength, by means of performing the analysis of rheological characteristics of nonpolymerized liquid compositions of heat-insulation material. The index of tensile strength in bending was the criterion for evaluating the mechanical strength of heat-insulating material. The critical volume concentrations of filling the heat-insulating material with glass
Plaza, Fernando; Wen, Yipei; Perone, Hanna; Xu, Yi; Liang, Xu
2017-01-15
Acid rock drainage (ARD) is one of the most adverse environmental problems of the mining industry. Surface and ground water affected by this pollution are characterized by their acidity and the high content of sulfates and metals/metalloids. In this study, alkaline clay (AC), an industrial waste with a high alkalinity, which is utilized in the alumina refining process, was used as the remediation material to inhibit pyrite oxidation in waste coal piles. Through a series of laboratory experiments (static and kinetic), complemented with field measurements and geochemical modeling, three important issues associated with this passive and sustainable ARD remediation method were investigated: 1) the potential use of alkaline clay as an ARD remediation material, 2) the adequate alkaline clay/coal refuse mixing ratio (AC/CR) to ensure pH values close to neutral conditions, and, 3) the implications for long-term performance, in terms of the trends of the main parameters involved in this process such as pH, concentrations of sulfate, iron and other dissolved contaminants. Both field measurements and the samples used for the experiments came from a local waste coal site. Through the analysis of the field measurements and the outcome of the laboratory experiments, AC proved to be an effective remediation material for ARD. Compared to those found in mine tailings, the concentrations of contaminants such as iron, manganese or sulfate were significantly reduced with this remediation approach. Moreover, results suggest a reliable long-term stability of the remediation (i.e. neutral pH conditions are maintained), thus enhancing the generation of iron precipitates that could produce pyrite grain coating. These processes also made the amended layer less porous, thus increased water retention and hindered oxygen diffusion.
Cianfrini, C.; Corcione, M.; Habib, E.; Quintino, A.
2017-06-01
Natural convection in air-filled rectangular cavities inclined with respect to gravity, so that the heated wall is facing upwards, is studied numerically under the assumption of two-dimensional laminar flow. A computational code based on the SIMPLE-C algorithm is used for the solution of the system of the mass, momentum and energy transfer governing equations. Simulations are performed for height-to-width aspect ratios of the enclosure from 0.25 to 8, Rayleigh numbers based on the length of the heated and cooled walls from 102 to 107, and tilting angles of the enclosure from 0° to 75°. The existence of an optimal tilting angle is confirmed for any investigated configuration, at a location that increases as the Rayleigh number is decreased, and the height-to-width aspect ratio of the cavity are increased, unless the value of the Rayleigh number is that corresponding to the onset of convection or just higher. Dimensionless correlating equations are developed to predict the optimal tilting angle and the heat transfer performance of the enclosure.
Johnston, Michael J W; Semple, Sean C; Klimuk, Sandra K; Edwards, Katarina; Eisenhardt, Merete L; Leng, Esther C; Karlsson, Göran; Yanko, Daniel; Cullis, Pieter R
2006-01-01
The anti-tumor efficacy of liposomal formulations of cell cycle dependent anticancer drugs is critically dependent on the rates at which the drugs are released from the liposomes. Previous work on liposomal formulations of vincristine have shown increasing efficacy for formulations with progressively slower release rates. Recent work has also shown that liposomal formulations of vincristine with higher drug-to-lipid (D/L) ratios exhibit reduced release rates. In this work, the effects of very high D/L ratios on vincristine release rates are investigated, and the antitumor efficacy of these formulations characterized in human xenograft tumor models. It is shown that the half-times (T(1/2)) for vincristine release from egg sphingomyelin/cholesterol liposomes in vivo can be adjusted from T(1/2) = 6.1 h for a formulation with a D/L of 0.025 (wt/wt) to T(1/2) = 117 h (extrapolated) for a formulation with a D/L ratio of 0.6 (wt/wt). The increase in drug retention at the higher D/L ratios appears to be related to the presence of drug precipitates in the liposomes. Variations in the D/L ratio did not affect the circulation lifetimes of the liposomal vincristine formulations. The relationship between drug release rates and anti-tumor efficacy was evaluated using a MX-1 human mammary tumor model. It was found that the antitumor activity of the liposomal vincristine formulations increased as D/L ratio increased from 0.025 to 0.1 (wt/wt) (T(1/2) = 6.1-15.6 h respectively) but decreased at higher D/L ratios (D/L = 0.6, wt/wt) (T(1/2) = 117 h). Free vincristine exhibited the lowest activity of all formulations examined. These results demonstrate that varying the D/L ratio provides a powerful method for regulating drug release and allows the generation of liposomal formulations of vincristine with therapeutically optimized drug release rates.
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Wega Trisunaryanti
2010-06-01
Full Text Available Optimation of time and catalyst/feed ratio in catalytic cracking of waste plastics fraction to gasoline fraction using Cr/Natural Zeolite catalyst has been studied.The natural zeolite was calcined by using nitrogen gas at 500 oC for 5 hours. The chromium supported on to the zeolite was prepared by ion exchange methode with Cr(NO33.9H2O solution with chromium/zeolite concentration of 1% (w/w. The zeolite samples were then calcined with nitrogen gas at 500 oC for 2 hours, oxidyzed with oxygen gas and reduced with hydrogen at 400 oC for 2 hours. The characterization of the zeolite catalyst by means of Si/Al ratio by UV-Vis spectroscopy, acidity with pyridine vapour adsorption and Na, Ca and Cr contents by atomic adsorption spectroscopy (AAS. The catalyst activity test was carried out in the cracking process of waste plastics fraction with boiling point range of 150 - 250 °C (consisted of C12 - C16 hydrocarbons at 450 oC for 30 min, 60 min and 90 min, and catalyst/feed ratio 1/1, 1/2, 1/3, ¼ (w/w. The result of catalyst activity test showed that the maximum number conversion of gasoline fraction (C5-C11 is 53,27% with relatively low coke formation using 1/3 catalyst/feed ratio and the cracking time of 60 min.. This catalyst has Si/Al ratio = 1,21 (w/w , acidity = 0,16 mmol/g and Na content = 0,81%, Ca content = 0,15% and Cr content 0,24%. Keywords: zeolite, catalytic cracking, gasoline, chromium.
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Aura M. Pedroza-Rodríguez
2013-01-01
Full Text Available C/N ratio and MnSO4 and CuSO4 concentrations were optimized for decolorization and chemical oxygen demand (COD removal of bleached Kraft pulp mill effluent by Trametes versicolor immobilized in polyurethane foam. Statistical differences (P<0.0001 at high C/N ratios (169, 2 mM CuSO4, and 0.071 mM MnSO4 were determined. Decolorization of 60.5%, COD removal of 55%, laccase (LAC 60 U/L, and manganese peroxidase (MnP 8.4 U/L were obtained. Maximum of decolorization (82%, COD removal (83%, LAC (443.5 U/L, and MnP (18 U/L activities at C/N ratio of 405 (6.75 mM CuSO4 and 0.22 mM MnSO4 was achieved in step 7 at 4 d. Positive correlation between the decolorization, COD removal, and enzymatic activity was found (P<0.0001. T. versicolor bioremediation capacity was evaluated in bubble column reactor during 8 d. Effluent was adjusted according to optimized parameters and treated at 25°C and air flow of 800 mL/min. Heterotrophic bacteria growth was not inhibited by fungus. After 4 d, 82% of COD reduction and 80% decolorization were recorded. Additionally, enzymatic activity of LAC (345 U/L and MnP (78 U/L was observed. The COD reduction and decolorization correlated positively (P<0.0001 with enzymatic activity. Chlorophenol removal was 98% of pentachlorophenol (PCP, 92% of 2,4,5-trichlorophenol (2,4,5-TCP, 90% of 3,4-dichlorophenol (3,4-DCP, and 99% of 4-chlorophenols (4CP.
Félix-Urquídez, Dalmira; Pérez-Urquiza, Melina; Valdez Torres, José-Benigno; León-Félix, Josefina; García-Estrada, Raymundo; Acatzi-Silva, Abraham
2016-01-05
Certified reference materials (CRMs) are required to guarantee the reliability of analytical measurements. The CRMs available in the field of genetically modified organisms (GMOs) are characterized using real-time polymerase chain reaction (qPCR). This technology has limited application, because of its dependence on a calibrant. The objective of this study was to obtain a method with higher metrological quality, to characterize the CRMs for their contents of T-nos/hmg copy number ratio in maize. A duplex droplet digital PCR (ddPCR) assay was developed and optimized by a central composite design. The developed method achieved an absolute limit of detection (LOD) of 11 cP T-nos, a relative LOD of 0.034%, a limit of quantification (LOQ) of 23 cP (relative LOQ of 0.08%), and a dynamic range of 0.08%-100% T-nos/hmg ratio. The specificity and applicability of the assay were established for the analysis of low T-nos concentrations (0.9%) in several corn varieties. The convenience of DNA digestion to reduce measurement bias in the case of multiple-copy binding was confirmed through an enzymatic restriction assay. Given its overall performance, this method can be used to characterize CRM candidates for their contents of T-nos/hmg ratio.
Carver, Charles S.; Scheier, Michael F.; Segerstrom, Suzanne C.
2010-01-01
Optimism is an individual difference variable that reflects the extent to which people hold generalized favorable expectancies for their future. Higher levels of optimism have been related prospectively to better subjective well-being in times of adversity or difficulty (i.e., controlling for previous well-being). Consistent with such findings, optimism has been linked to higher levels of engagement coping and lower levels of avoidance, or disengagement, coping. There is evidence that optimism is associated with taking proactive steps to protect one's health, whereas pessimism is associated with health-damaging behaviors. Consistent with such findings, optimism is also related to indicators of better physical health. The energetic, task-focused approach that optimists take to goals also relates to benefits in the socioeconomic world. Some evidence suggests that optimism relates to more persistence in educational efforts and to higher later income. Optimists also appear to fare better than pessimists in relationships. Although there are instances in which optimism fails to convey an advantage, and instances in which it may convey a disadvantage, those instances are relatively rare. In sum, the behavioral patterns of optimists appear to provide models of living for others to learn from. PMID:20170998
Pearce, Charles
2009-01-01
Focuses on mathematical structure, and on real-world applications. This book includes developments in several optimization-related topics such as decision theory, linear programming, turnpike theory, duality theory, convex analysis, and queuing theory.
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Maoinser Mohd Azuwan
2014-07-01
Full Text Available Drilling hybrid fiber reinforced polymer (HFRP composite is a novel approach in fiber reinforced polymer (FRP composite machining studies as this material combining two different fibers in a single matrix that resulted in considerable improvement in mechanical properties and cost saving as compared to conventional fiber composite material. This study presents the development and optimized way of drilling HFRP composite at various drilling parameters such as drill point angle, feed rate and cutting speed by using the full factorial design experiment with the combination of analysis of variance (ANOVA approach and signal to noise (S/N ratio analysis. The results identified optimum drilling parameters for drilling the HFRP composite using small drill point angle at low feed rate and medium cutting speed that resulted in lower thrust force.
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Dr. Nimai Mukhopadhyay
2017-04-01
Full Text Available Energy is at scarcity, crisis of energy is leading towards a world where growth might come to an absolute hold and optimizing the processes might give a way out to save energy for future generations and give some positive way out. In this situation if the maximum heat energy (Q is absorbed by the evaporator inside the cold room through convective heat transfer process in terms of –heat transfer due to convection and heat transfer due to condensation and also heat enter in the cold store due to air exchange through the windows more energy has to be wasted to maintain the evaporator space at the desired temperature range of 2-6 degree centigrade. In this paper we have tried to optimize the heat gain by the air exchange through the windows of cold storage in the evaporator space using regression analysis. Temperature difference (dT, Height of cold store Window (H and Relative Humidity (RH are the basic variable and three ranges are taken each of them in the model development. Graphical interpretations from the model justify the reality through S/N ratio calculation and ANOVA analysis
Servin, Manuel; Garnica, Guillermo
2016-01-01
Synthesis of single-wavelength temporal phase-shifting algorithms (PSA) for interferometry is well-known and firmly based on the frequency transfer function (FTF) paradigm. Here we extend the single-wavelength FTF-theory to dual and multi-wavelength PSA-synthesis when several simultaneous laser-colors are present. The FTF-based synthesis for dual-wavelength PSA (DW-PSA) is optimized for high signal-to-noise ratio and minimum number of temporal phase-shifted interferograms. The DW-PSA synthesis herein presented may be used for interferometric contouring of discontinuous industrial objects. Also DW-PSA may be useful for DW shop-testing of deep free-form aspheres. As shown here, using the FTF-based synthesis one may easily find explicit DW-PSA formulae optimized for high signal-to-noise and high detuning robustness. To this date, no general synthesis and analysis for temporal DW-PSAs has been given; only had-hoc DW-PSAs formulas have been reported. Consequently, no explicit formulae for their spectra, their sign...
Zhang, Xinai; Jiang, Yuxiang; Huang, Chenyong; Shen, Jianzhong; Dong, Xiaoya; Chen, Guangwei; Zhang, Wen
2017-03-15
An amplified electrochemical immunosensor was developed by exploiting poly(diallyldimethylammonium chloride)-functionalized graphene oxide and gold nanoparticles (GO-PDDA@AuNP) as sensing platform. Highlight of this work was to investigate and optimize the ratio of GO-PDDA to AuNP for sensitivity enhancement. The suitable GO-PDDA@AuNP nanocomposites were proven to not only provide an excellent biocompatible microenvironment for the immobilized antibody, but also accelerate electron transfer to enhance electrochemical signal. Moreover, the {dAb-Au-THi} nanoprobes as biorecognition elements were designed by utilizing the amplification effect of AuNPs to load detection antibody (dAb) and enormous thionine (THi), in which dAb was used for specific recognition of E. coli and THi served as electroactive species. Under optimal conditions, experimental results demonstrated that the variations (ΔI) in the peak current linearly depended on the logarithmic value of E. coli concentration from 50 to 5.0×10(6)cfumL(-)(1) with the detection limit of 35cfumL(-1). Recovery experiments were also performed for E. coli assay in dairy product (pure fresh milk, yogurt in shelf-life and expired yogurt), and the recoveries of standard additions were in the range of 89.7-112.6%. The excellent performance of the proposed strategy indicated its promising prospect as a valuable tool to estimate the quality deterioration in dairy product. Copyright © 2016 Elsevier B.V. All rights reserved.
Obesity Related Indices for Screening of Obesity in Adolescents
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Amit Sohani
2015-09-01
Full Text Available Background: Obesity is a fast growing problem in the developing countries like India and is now known to be associated with increased health risk. Realizing the fact that the obesity in adolescent age group does not receive the deserved attention in the prevention and control programme, the present study was undertaken on 585 adolescent subjects studying in one college and three schools. Aims and Objectives: 1. To study the prevalence of overweight and obesity in adolescent population. 2. To find the association of body mass index (BMI with important parameters like skin fold thickness, waist circumference and waist to hip ratio. Methods: It was a cross sectional observational study. The study population was school and college going adolescents in the age group of 11-19 years. The estimated sample size for present study is 585 students. The subjects were screened by body mass index, skin fold thickness, waist circumference and waist to hip ratio. Results: The prevalence of overweight and obesity was 19.14% and 4.44% respectively. It was found that there was strong association between the waist circumference with overweight and obesity. Similarly a strong association between waist to hip ratio with overweight and obesity has been found. Also it was found that there was a strong association between skin fold thickness with overweight and obesity. Skin-fold thickness has more sensitivity as compared to waist circumference and waist to hip ratio. Waist to hip ratio has got maximum specificity amongst all but when both sensitivity and specificity criteria are considered together waist circumference stands out. Conclusion: It was found that the prevalence of overweight and obesity was 19.14% and 4.44% respectively. Skin-fold thickness has more sensitivity as compared waist circumference and waist to hip ratio. Waist to hip ratio has got maximum specificity. When sensitivity and specificity criteria are considered together waist circumference can be
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Tandi E Matsha
Full Text Available BACKGROUND: The proposed waist-to-height ratio (WHtR cut-off of 0.5 is less optimal for cardiometabolic risk screening in children in many settings. The purpose of this study was to determine the optimal WHtR for children from South Africa, and investigate variations by gender, ethnicity and residence in the achieved value. METHODS: Metabolic syndrome (MetS components were measured in 1272 randomly selected learners, aged 10-16 years, comprising of 446 black Africans, 696 mixed-ancestry and 130 Caucasians. The Youden's index and the closest-top-left (CTL point approaches were used to derive WHtR cut-offs for diagnosing any two MetS components, excluding the waist circumference. RESULTS: The two approaches yielded similar cut-off in girls, 0.465 (sensitivity 50.0, specificity 69.5, but two different values in boys, 0.455 (42.9, 88.4 and 0.425 (60.3, 67.7 based on the Youden's index and the CTL point, respectively. Furthermore, WHtR cut-off values derived differed substantially amongst the regions and ethnic groups investigated, whereby the highest cut-off was observed in semi-rural and white children, respectively, Youden's index0.505 (31.6, 87.1 and CTL point 0.475 (44.4, 75.9. CONCLUSION: The WHtR cut-off of 0.5 is less accurate for screening cardiovascular risk in South African children. The optimal value in this setting is likely gender and ethnicity-specific and sensitive to urbanization.
Vanderstichele, Hugo Marcel Johan; Janelidze, Shorena; Demeyer, Leentje; Coart, Els; Stoops, Erik; Herbst, Victor; Mauroo, Kimberley; Brix, Britta; Hansson, Oskar
2016-01-01
Background: Reduced cerebrospinal fluid (CSF) concentration of amyloid-β1-42 (Aβ1-42) reflects the presence of amyloidopathy in brains of subjects with Alzheimer’s disease (AD). Objective: To qualify the use of Aβ1-42/Aβ1-40 for improvement of standard operating procedures (SOP) for measurement of CSF Aβ with a focus on CSF collection, storage, and analysis. Methods: Euroimmun ELISAs for CSF Aβ isoforms were used to set up a SOP with respect to recipient properties (low binding, polypropylene), volume of tubes, freeze/thaw cycles, addition of detergents (Triton X-100, Tween-20) in collection or storage tubes or during CSF analysis. Data were analyzed with linear repeated measures and mixed effects models. Results: Optimization of CSF analysis included a pre-wash of recipients (e.g., tubes, 96-well plates) before sample analysis. Using the Aβ1-42/Aβ1-40 ratio, in contrast to Aβ1-42, eliminated effects of tube type, additional freeze/thaw cycles, or effect of CSF volumes for polypropylene storage tubes. ‘Low binding’ tubes reduced the loss of Aβ when aliquoting CSF or in function of additional freeze/thaw cycles. Addition of detergent in CSF collection tubes resulted in an almost complete absence of variation in function of collection procedures, but affected the concentration of Aβ isoforms in the immunoassay. Conclusion: The ratio of Aβ1-42/Aβ1-40 is a more robust biomarker than Aβ1-42 toward (pre-) analytical interfering factors. Further, ‘low binding’ recipients and addition of detergent in collection tubes are able to remove effects of SOP-related confounding factors. Integration of the Aβ1-42/Aβ1-40 ratio and ‘low-binding tubes’ into guidance criteria may speed up worldwide standardization of CSF biomarker analysis. PMID:27258423
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Jiahong Zhang
2016-10-01
Full Text Available In order to meet the requirement of high sensitivity and signal-to-noise ratios (SNR, this study develops and optimizes a piezoresistive pressure sensor by using double silicon nanowire (SiNW as the piezoresistive sensing element. First of all, ANSYS finite element method and voltage noise models are adopted to optimize the sensor size and the sensor output (such as sensitivity, voltage noise and SNR. As a result, the sensor of the released double SiNW has 1.2 times more sensitivity than that of single SiNW sensor, which is consistent with the experimental result. Our result also displays that both the sensitivity and SNR are closely related to the geometry parameters of SiNW and its doping concentration. To achieve high performance, a p-type implantation of 5 × 1018 cm−3 and geometry of 10 µm long SiNW piezoresistor of 1400 nm × 100 nm cross area and 6 µm thick diaphragm of 200 µm × 200 µm are required. Then, the proposed SiNW pressure sensor is fabricated by using the standard complementary metal-oxide-semiconductor (CMOS lithography process as well as wet-etch release process. This SiNW pressure sensor produces a change in the voltage output when the external pressure is applied. The involved experimental results show that the pressure sensor has a high sensitivity of 495 mV/V·MPa in the range of 0–100 kPa. Nevertheless, the performance of the pressure sensor is influenced by the temperature drift. Finally, for the sake of obtaining accurate and complete information over wide temperature and pressure ranges, the data fusion technique is proposed based on the back-propagation (BP neural network, which is improved by the particle swarm optimization (PSO algorithm. The particle swarm optimization–back-propagation (PSO–BP model is implemented in hardware using a 32-bit STMicroelectronics (STM32 microcontroller. The results of calibration and test experiments clearly prove that the PSO–BP neural network can be effectively applied
Choi, Eun-Ji; Kim, Jin-Woo; Kim, Soo-Jung; Seo, Seung-Oh; Lane, Stephan; Park, Yong-Cheol; Jin, Yong-Su; Seo, Jin-Ho
2016-11-01
Galactose and glucose are two of the most abundant monomeric sugars in hydrolysates of marine biomasses. While Saccharomyces cerevisiae can ferment galactose, its uptake is tightly controlled in the presence of glucose by catabolite repression. It is desirable to construct engineered strains capable of simultaneous utilization of glucose and galactose for producing biofuels and chemicals from marine biomass. The MTH1 gene coding for transcription factor in glucose signaling was mutated in a pyruvate decarboxylase (Pdc)-deficient S. cerevisiae expressing heterologous 2,3-butanediol (2,3-BD) biosynthetic genes. The engineered S. cerevisiae strain consumed glucose and galactose simultaneously and produced 2,3-BD as a major product. Total sugar consumption rates increased with a low ratio of glucose/galactose, though, occurrence of the glucose depletion in a fed-batch fermentation decreased 2,3-BD production substantially. Through optimizing the profiles of sugar concentrations in a fed-batch cultivation with the engineered strain, 99.1 ± 1.7 g/L 2,3-BD was produced in 143 hours with a yield of 0.353 ± 0.022 g 2,3-BD/g sugars. This result suggests that simultaneous and efficient utilization of glucose and galactose by the engineered yeast might be applicable to the economical production of not only 2,3-BD, but also other biofuels and chemicals from marine biomass.
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Douaud A.
2006-11-01
Full Text Available Une synthèse des études entreprises à l'institut Français du Pétrole pour la compréhension des phénomènes de combustion, de transferts thermiques, de cliquetis et leur maîtrise pour l'optimisation du rendement de chambre à haut taux de compression conduit à proposer deux thèmes de réalisation : - chambre calme à double allumage; - chambre turbulente à effet de chasse. Les avantages de principe et les contraintes associés à la mise en oeuvre de chaque type de chambre sont examinés. A synthesis of research undertaken at the Institut Français du Pétrole on understanding combustion, heat-transfer and knock phenomena and on mastering them to optimize the efficiency of high-compression-ratio combustion chambers has led to the proposing of two topics of implementation:(a calm chamber with dual ignition;(b turbulent chamber with squish effect. The advantages of the principle and the constraints connected to the implementation of each type of chamber are examined.
Renaud, J.E.O.
2004-01-01
The optimal value of the firm under the new Dutch income tax reform act in 2002, is reconsidered in this discussion paper. Tax shield of debt-financing and the aggregate tax payments of its joint investors are simultaneously considered. A more-period model is presented for making integrated decision
Renaud, Jan
2004-01-01
The optimal value of the firm under the new Dutch income tax reform act in 2002, is reconsidered in this discussion paper. Tax shield of debt-financing and the aggregate tax payments of its joint investors are simultaneously considered. A more-period model is presented for making integrated decision
Renaud, J.E.O.
The optimal value of the firm under the new Dutch income tax reform act in 2002, is reconsidered in this discussion paper. Tax shield of debt-financing and the aggregate tax payments of its joint investors are simultaneously considered. A more-period model is presented for making integrated
Renaud, Jan
2004-01-01
The optimal value of the firm under the new Dutch income tax reform act in 2002, is reconsidered in this discussion paper. Tax shield of debt-financing and the aggregate tax payments of its joint investors are simultaneously considered. A more-period model is presented for making integrated
Renaud, J.E.O.
2004-01-01
The optimal value of the firm under the new Dutch income tax reform act in 2002, is reconsidered in this discussion paper. Tax shield of debt-financing and the aggregate tax payments of its joint investors are simultaneously considered. A more-period model is presented for making integrated decision
Renaud, Jan
2004-01-01
The optimal value of the firm under the new Dutch income tax reform act in 2002, is reconsidered in this discussion paper. Tax shield of debt-financing and the aggregate tax payments of its joint investors are simultaneously considered. A more-period model is presented for making integrated decision
National Research Council Canada - National Science Library
Ting Hou; Liping Zhang; Yuchen Chen
2014-01-01
.... In this paper, a kind of fuzzy self-optimizing control based on differential evolution algorithm is proposed, which applied in the power plant boiler system, the boiler combustion efficiency has been...
Gehre, Matthias; Renpenning, Julian; Geilmann, Heike; Qi, Haiping; Coplen, Tyler B.; Kümmel, Steffen; Ivdra, Natalija; Brand, Willi A.; Schimmelmann, Arndt
2017-01-01
Rationale: Accurate hydrogen isotopic analysis of halogen- and sulfur-bearing organics has not been possible with traditional high-temperature conversion (HTC) because the formation of hydrogen-bearing reaction products other than molecular hydrogen (H2) is responsible for non-quantitative H2 yields and possible hydrogen isotopic fractionation. Our previously introduced, new chromium-based EA-Cr/HTC-IRMS (Elemental Analyzer–Chromium/High-Temperature Conversion Isotope Ratio Mass Spectrometry) technique focused primarily on nitrogen-bearing compounds. Several technical and analytical issues concerning halogen- and sulfur-bearing samples, however, remained unresolved and required further refinement of the reactor systems.
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Mojdeh Dinarvand
2013-01-01
Full Text Available The study is to identify the extraction of intracellular inulinase (exo- and endoinulinase and invertase as well as optimization medium composition for maximum productions of intra- and extracellular enzymes from Aspergillus niger ATCC 20611. From two different methods for extraction of intracellular enzymes, ultrasonic method was found more effective. Response surface methodology (RSM with a five-variable and three-level central composite design (CCD was employed to optimize the medium composition. The effect of five main reaction parameters including sucrose, yeast extract, NaNO3, Zn+2, and Triton X-100 on the production of enzymes was analyzed. A modified quadratic model was fitted to the data with a coefficient of determination (R2 more than 0.90 for all responses. The intra-extracellular inulinase and invertase productions increased in the range from 16 to 8.4 times in the optimized medium (10% (w/v sucrose, 2.5% (w/v yeast extract, 2% (w/v NaNO3, 1.5 mM (v/v Zn+2, and 1% (v/v Triton X-100 by RSM and from around 1.2 to 1.3 times greater than in the medium optimized by one-factor-at-a-time, respectively. The results of bioprocesses optimization can be useful in the scale-up fermentation and food industry.
Avercheva, O. V.; Berkovich, Yu. A.; Konovalova, I. O.; Radchenko, S. G.; Lapach, S. N.; Bassarskaya, E. M.; Kochetova, G. V.; Zhigalova, T. V.; Yakovleva, O. S.; Tarakanov, I. G.
2016-11-01
The aim of this work were to choose a quantitative optimality criterion for estimating the quality of plant LED lighting regimes inside space greenhouses and to construct regression models of crop productivity and the optimality criterion depending on the level of photosynthetic photon flux density (PPFD), the proportion of the red component in the light spectrum and the duration of the duty cycle (Chinese cabbage Brassica сhinensis L. as an example). The properties of the obtained models were described in the context of predicting crop dry weight and the optimality criterion behavior when varying plant lighting parameters. Results of the fractional 3-factor experiment demonstrated the share of the PPFD level participation in the crop dry weight accumulation was 84.4% at almost any combination of other lighting parameters, but when PPFD value increased up to 500 μmol m-2 s-1 the pulse light and supplemental light from red LEDs could additionally increase crop productivity. Analysis of the optimality criterion response to variation of lighting parameters showed that the maximum coordinates were the following: PPFD = 500 μmol m-2 s-1, about 70%-proportion of the red component of the light spectrum (PPFDLEDred/PPFDLEDwhite = 1.5) and the duty cycle with a period of 501 μs. Thus, LED crop lighting with these parameters was optimal for achieving high crop productivity and for efficient use of energy in the given range of lighting parameter values.
Avercheva, O V; Berkovich, Yu A; Konovalova, I O; Radchenko, S G; Lapach, S N; Bassarskaya, E M; Kochetova, G V; Zhigalova, T V; Yakovleva, O S; Tarakanov, I G
2016-11-01
The aim of this work were to choose a quantitative optimality criterion for estimating the quality of plant LED lighting regimes inside space greenhouses and to construct regression models of crop productivity and the optimality criterion depending on the level of photosynthetic photon flux density (PPFD), the proportion of the red component in the light spectrum and the duration of the duty cycle (Chinese cabbage Brassica сhinensis L. as an example). The properties of the obtained models were described in the context of predicting crop dry weight and the optimality criterion behavior when varying plant lighting parameters. Results of the fractional 3-factor experiment demonstrated the share of the PPFD level participation in the crop dry weight accumulation was 84.4% at almost any combination of other lighting parameters, but when PPFD value increased up to 500µmol m(-2)s(-1) the pulse light and supplemental light from red LEDs could additionally increase crop productivity. Analysis of the optimality criterion response to variation of lighting parameters showed that the maximum coordinates were the following: PPFD = 500µmol m(-2)s(-1), about 70%-proportion of the red component of the light spectrum (PPFDLEDred/PPFDLEDwhite = 1.5) and the duty cycle with a period of 501µs. Thus, LED crop lighting with these parameters was optimal for achieving high crop productivity and for efficient use of energy in the given range of lighting parameter values. Copyright © 2016 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.
Haque, Md. Mozammel; Kim, Sang Yun; Kim, Gil Won; Kim, Pil Joo
2015-01-01
The cultivation of a winter cover crop as green manure is strongly recommended to improve soil quality in mono-rice paddy systems; however, the biomass is largely removed to feed cattle in many Asian regions. To determine the minimum recycling ratio of the biomass that can sustain soil organic carbo
Ravindran, B; Mnkeni, P N S
2016-09-01
The main objective of the present study was to determine the optimum C/N ratio for converting waste paper and chicken manure to nutrient-rich manure with minimum toxicity. Six treatments of C/N ratio 20, 30, 40, 50, 60, and 70 (T1, T2, T3, T4, T5, and T6, respectively) achieved by mixing chicken manure with shredded paper were used. The study involved a composting stage for 20 days followed by vermicomposting with Eisenia fetida for 7 weeks. The results revealed that 20 days of composting considerably degraded the organic waste mixtures from all treatments and a further 7 weeks of vermiculture significantly improved the bioconversion and nutrient value of all treatments. The C/N ratio of 40 (T3) resulted in the best quality vermicompost compared to the other treatments. Earthworm biomass was highest at T3 and T4 possibly due to a greater reduction of toxic substances in these waste mixtures. The total N, total P, and total K concentrations increased with time while total carbon, C/N ratio, electrical conductivity (EC), and heavy metal content gradually decreased with time during the vermicomposting process. Scanning electron microscopy (SEM) revealed the intrastructural degradation of the chicken manure and shredded paper matrix which confirmed the extent of biodegradation of treatment mixtures as result of the composting and vermicomposting processes. Phytotoxicity evaluation of final vermicomposts using tomato (Lycopersicon esculentum), radish (Raphanus sativus), carrot (Daucus carota), and onion (Allium cepa) as test crops showed the non-phytotoxicity of the vermicomposts to be in the order T3 > T4 > T2 > T1 > T5 > T6. Generally, the results indicated that the combination of composting and vermicomposting processes is a good strategy for the management of chicken manure/paper waste mixtures and that the ideal C/N ratio of the waste mixture is 40 (T3).
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
A new procedure of determining optimal C/N (the rate of carbon source to nitrogen source) of mixed distillers' grains for combined bacteria synergic fermentation is established. At the same time an improved method evaluating bacteria growth, called method of dry cell weighing by filtering is developed. For each combination of C and N , their initial and residual contents before and after fermentation respectively are determined. Then followed the calculation of utilization of C and N sources by the compound bacteria. The optimal C/N is finally located from among the utilization of C and N of several combinations and the weight of produced mass of oven-dried thallus The conditions of fermentation are: inoculum size 10%, temperature 30.0℃, rotational speed 170 r/min, shake culture time 48h. The best results obtained from orthogonal experiments are: maximum mass of oven dried thallus is 14.693g in a liter liquid medium, maximum utilization rate of carbon source is 98.13% and maximum utilization rate of nitrogen is 78.14%. Optimal C/N is 5.1.
Energy Technology Data Exchange (ETDEWEB)
Ro, K.S.; Arikere, B.; Sarkar, B.K.; Nagaraj, N.K.; Al-Shammary, S.; Al-Butairi, A. [Saudi Iron and Steel Co., Al-Jubail (Saudi Arabia)
2004-07-01
This paper described trials conducted to achieve a yield-to-tensile ratio lower than 0.85 for API X60 line pipes. The trials were based on the parameters affecting the mechanical and physical properties of hot-rolled coils. The production scale trials were performed by controlling: (1) finish rolling temperature; (2) coiling temperature; (3) cooling rates. The study also aimed to determine the effect of grain size and microstructure on yield-to-tensile ratios. A high reduction at approximately 1050 degrees C was provided at the roughing mill to ensure a transfer bar with a fine recrystallized austenitic grain size. A laminar cooling strategy was used to achieve a smaller grain size as well as to transform the austenites to ferrite and pearlite. A higher cooling rate (CR) was used to increase ferrite nucleation sites. Photomicrographs were used to show differences in grain size, grain shape, and the distribution of pearlite in the samples. A volume fraction analysis showed that the pearlite content varied from 8 per cent to 11 per cent in the trials. Samples for testing were collected from pipes made using a cage-forming process and a linear forming process. Results showed that the average yield strength drop from coil to pipe was 43.2 MPa, with a range of 30 to 90 MPa. Significant differences in yield strength drop were noted for the linear forming and cage forming processes. Results suggested that higher deformation temperatures combined with normal coiling temperatures and consistent water cooling patterns will provide optimum yield and tensile strengths with lower yield ratios. It was concluded that that a yield-to-tensile ratio of 0.84-0.88 can be achieved with API-X60 hot-rolled coils using the new process. 8 refs., 4 tabs., 6 figs.
Babbs, Charles F.; Nadkarni, Vinay
2003-01-01
Objective: To estimate the optimum ratio of chest compressions to ventilations for onerescuer CPR that maximizes systemic oxygen delivery in children. Method: Equations describing oxygen delivery and blood flow during CPR as functions of the number of compressions and the number of ventilations delivered over time were adapted from the former work of Babbs and Kern. These equations were solved explicitly as a function of body weight, using scaling algorithms based upon principles of developme...
Directory of Open Access Journals (Sweden)
Bharat Raj Singh,
2010-03-01
Full Text Available This paper deals with new concept of compressed air energy storage system using atmospheric air at ambient temperature as a zero pollution power source for running motorbikes. The proposed motorbike is equipped with an air turbine in place of an internal combustion engine, and transforms the energy of the compressed air into shaft work. The mathematical modeling and performance evaluation of such small capacity compressed air driven vaned type novel air turbine is presented here. The effect of isobaric admission and adiabatic expansion of high pressure air for different rotor to casing diameter ratios with respect to different vane angles (number of vanes have been considered and analyzed. It is found that the shaft work output is optimum for some typical values of rotor to casing diameter ratios at a particular vane angle (i.e. no. of vanes. In this study, when casing diameter is considered 100 mm, and rotor to casing diameter ratios are kept 0.70 to 0.55, the average maximum power is obtained to the order of 4.95 kW (6.6 HP which is sufficient to run motorbikes.
Directory of Open Access Journals (Sweden)
Piroska Szabó-Révész
2011-11-01
Full Text Available The objectives of this work were the formulation optimization of the preparation process parameters and to evaluate spray-dried sustained-release microspheres using ammonio methacrylate copolymer (AMC as a polymer matrix. The effects of log P and the concentrations of the cosolvents (acetone, methyl ethyl ketone and n-butyl acetate and different drug/copolymer ratios as independent variables on the physicochemical parameters (the W1/O emulsion viscosity, the microsphere production yield, the average particle size, the encapsulation efficiency and the cumulative in vitro drug release as dependent variables were studied. The optimization was carried out on the basis of the 33 factorial design study. The optimization process results showed that addition of polar cosolvents proved effective, linear relationships were observed between the independent and the dependent variables. The best conditions were achieved by microspheres prepared by using a low/medium cosolvent log P, cosolvent concentration of 25–50% v/v and a drug/copolymer ratio of 1:16. The microspheres ensured sustained release with Nernst and Baker-Lonsdale release profiles.
A Kind of Design and Optimization of Gear Ratio for Hybrid Electric Vehicle%一种混合动力电动汽车速比设计与优化方法
Institute of Scientific and Technical Information of China (English)
沈雨霏; 陈辛波
2012-01-01
针对一种PHEV混合动力电动汽车,在动力源功率一定并且需要保证整车动力性要求的前提下,对其传动系速比进行合理的设计与优化.仿真结果表明,可以通过调整速比与电机的最大扭矩,满足车辆动力性要求,达到减小电机体积及改善整车安装性能的目的；同时还可降低离合器的滑磨功损失,提高离合器使用寿命.%For a PHEV hybrid electric vehicle, we design and optimize the gear ratio reasonably when the engine power is unchanged as well as the motor power. In this way, we can guarantee the dynamic performance of the vehicle. The simulation results show that the vehicle can meet the dynamic performance requirements by adjusting the gear ratio and the maximal torque of the motor. Also we can downsize the motor volume to make the installation of the motor much more convenient. Meanwhile, the slipping frictional power of clutch can be reduced through the optimization of gear ratio so that the service life of clutch can be extended.
Optimal V̇O2max-to-mass ratio for predicting 15 km performance among elite male cross-country skiers
Directory of Open Access Journals (Sweden)
Carlsson T
2015-12-01
Full Text Available Tomas Carlsson,1,2 Magnus Carlsson,1,2 Daniel Hammarström,3 Bent R Rønnestad,3 Christer B Malm,2 Michail Tonkonogi1 1School of Education, Health and Social Studies, Dalarna University, Falun, 2Sports Medicine Unit, Umeå University, Umeå, Sweden; 3The Lillehammer Research Center for Medicine and Exercise Physiology, Lillehammer University College, Lillehammer, Norway Abstract: The aim of this study was 1 to validate the 0.5 body-mass exponent for maximal oxygen uptake (V̇O2max as the optimal predictor of performance in a 15 km classical-technique skiing competition among elite male cross-country skiers and 2 to evaluate the influence of distance covered on the body-mass exponent for V̇O2max among elite male skiers. Twenty-four elite male skiers (age: 21.4±3.3 years [mean ± standard deviation] completed an incremental treadmill roller-skiing test to determine their V̇O2max. Performance data were collected from a 15 km classical-technique cross-country skiing competition performed on a 5 km course. Power-function modeling (ie, an allometric scaling approach was used to establish the optimal body-mass exponent for V̇O2max to predict the skiing performance. The optimal power-function models were found to be race speed = 8.83 • (V̇O2max m-0.530.66 and lap speed = 5.89 • (V̇O2max m-(0.49+0.018lap0.43e0.010age, which explained 69% and 81% of the variance in skiing speed, respectively. All the variables contributed to the models. Based on the validation results, it may be recommended that V̇O2max divided by the square root of body mass (mL • min-1 • kg-0.5 should be used when elite male skiers’ performance capability in 15 km classical-technique races is evaluated. Moreover, the body-mass exponent for V̇O2max was demonstrated to be influenced by the distance covered, indicating that heavier skiers have a more pronounced positive pacing profile (ie, race speed gradually decreasing throughout the race compared to that of lighter
Directory of Open Access Journals (Sweden)
Ramaraj Ravi
2012-01-01
Full Text Available Problem statement: Virtual private networks have provided customers with a secure and low-cost communication environment. Approach: The COVPA, the provisioning algorithm for a Virtual Private Network service, which built and managed VPNs on demand. Results: The COVPA allowed each VPN to have guaranteed resources and customized control and supported a highly dynamic VPN service where creation and modification operations took place on fast timescales at reduced cost. Also, it allowed the sharing of bandwidth on the links to reduce the cost. A design process is described, that attempts to satisfy the goals of both the customer and the VPN Service Provider (VSP. Conclusion/Recommendations: The performance of the proposed algorithm is analyzed in terms of cost, the number of nodes, the number of VPN nodes, asymmetric ratio and rejection ratio with the breadth first search, steiner tree and primal dual algorithms. With the enhancement on the design process, the COVPA performs better than the breadth first search, steiner tree and primal dual algorithms
Energy Technology Data Exchange (ETDEWEB)
Talukder, Srijeeta; Chaudhury, Pinaki, E-mail: pinakc@rediffmail.com [Department of Chemistry, University of Calcutta, 92 A P C Road, Kolkata 700 009 (India); Sen, Shrabani [Department of Chemistry, Rammohan College, 102/1, Raja Rammohan Sarani, Kolkata 700 009 (India); Shandilya, Bhavesh K. [Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076 (India); Sharma, Rahul [Department of Chemistry, St. Xavier’s College, 30 Mother Teresa Sarani, Kolkata 700 016 (India); Adhikari, Satrajit, E-mail: pcsa@iacs.res.in [Department of Physical Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India)
2015-10-14
We propose a strategy of using a stochastic optimization technique, namely, simulated annealing to design optimum laser pulses (both IR and UV) to achieve greater fluxes along the two dissociating channels (O{sup 18} + O{sup 16}O{sup 16} and O{sup 16} + O{sup 16}O{sup 18}) in O{sup 16}O{sup 16}O{sup 18} molecule. We show that the integrated fluxes obtained along the targeted dissociating channel is larger with the optimized pulse than with the unoptimized one. The flux ratios are also more impressive with the optimized pulse than with the unoptimized one. We also look at the evolution contours of the wavefunctions along the two channels with time after the actions of both the IR and UV pulses and compare the profiles for unoptimized (initial) and optimized fields for better understanding the results that we achieve. We also report the pulse parameters obtained as well as the final shapes they take.
Li, S S; Loor, J J; Liu, H Y; Liu, L; Hosseini, A; Zhao, W S; Liu, J X
2017-08-01
Amino acids are the building blocks of proteins and serve as key molecular components upstream of the signaling pathways that regulate protein synthesis. The objective of this study was to systematically investigate the effect of essential AA ratios on milk protein synthesis in vitro and to elucidate some of the underlying mechanisms. Triplicate cultures of MAC-T cells and bovine mammary tissue explants (MTE) were incubated with the optimal AA ratio (OPAA; Lys:Met, 2.9:1; Thr:Phe, 1.05:1; Lys:Thr, 1.8:1; Lys:His, 2.38:1; and Lys:Val, 1.23:1) in the presence of rapamycin (control), OPAA, a Lys:Thr ratio of 2.1:1, a Lys:Thr ratio of 1.3:1, a Lys:His ratio of 3.05:1, or a Lys:Val ratio of 1.62:1 for 12 h; the other AA concentrations were equal to OPAA. In some experiments, the cells were cultured with OPAA with or without rapamycin (100 ng/mL) or with mammalian target of rapamycin (mTOR) small interference RNA, and the MTE were exposed to OPAA with rapamycin for β-casein expression. Among the treatments, the expression of β-casein was greatest in the MTE cultured with OPAA. In MAC-T cells, the OPAA upregulated the mRNA expression of SLC1A5 and SLC7A5 but downregulated the expression of IRS1, AKT3, EEF1A1, and EEF2 compared with the control. The OPAA had no effect on the mTOR phosphorylation status but increased the phosphorylation of S6K1 and RPS6. When the MTE were treated with rapamycin in the presence of OPAA, the expression of β-casein was markedly decreased. The phosphorylation of RPS6 and 4EBP1 also was reduced in MAC-T cells. A similar negative effect on the expression of RPS6KB1 and EIF4EBP1 was detected when the cells were cultured with either rapamycin or mTOR small interference RNA. The optimal AA ratio stimulated β-casein expression partly by enhancing the transport of AA into the cells, cross-talk with insulin signaling and a subsequent enhancement of mTOR signaling, or translation elongation in both MAC-T cells and bovine MTE. Copyright © 2017
Association of Serum Thyrotropin with Anthropometric Markers of Obesity in the General Population
DEFF Research Database (Denmark)
Tiller, Daniel; Ittermann, Till; Greiser, Karin H
2016-01-01
BACKGROUND: Except from associations study with body weight, there are few longitudinal data regarding the association between thyroid function and anthropometric measurements such as waist circumference, waist-to-hip ratio, or waist-to height ratio. OBJECTIVE: This study aimed to investigate the...
Measures of abdominal adiposity and the risk of stroke
DEFF Research Database (Denmark)
Bodenant, Marie; Kuulasmaa, Kari; Wagner, Aline
2011-01-01
Excess fat accumulates in the subcutaneous and visceral adipose tissue compartments. We tested the hypothesis that indicators of visceral adiposity, namely, waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR), are better predictors of stroke risk than body mass in...
Zhang, Zhongyang; Berti, Emanuele
2011-01-01
We study the effect of black hole spin on the accuracy of the post-Newtonian approximation. We focus on the gravitational energy flux for the quasicircular, equatorial, extreme mass-ratio inspiral of a compact object into a Kerr black hole of mass M and spin J. For a given dimensionless spin a=J/M^2 (in geometrical units), the energy flux depends only on the orbital velocity v or (equivalently) on the Boyer-Lindquist orbital radius r. We investigate the formal region of validity of the Taylor post-Newtonian expansion of the energy flux (which is known up to order v^8 beyond the quadrupole formula), generalizing previous work by two of us. The "error function" used to determine the region of validity of the post-Newtonian expansion can have two qualitatively different kinds of behavior, and we deal with these two cases separately. We find that, at any fixed post-Newtonian order, the edge of the region of validity (as measured by v/v_{ISCO}, where v_{ISCO} is the orbital velocity at the innermost stable circula...
Versey, H. Shellae; Kaplan, George A.
2012-01-01
Hostility may be related to risk factors for cardiovascular disease (CVD), such as blood pressure. However, the process by which hostility affects blood pressure is not fully understood. The current study sought to evaluate abdominal obesity (waist-to-hip ratio [WHR]) as a potential mediator and modifier of the relationship between cynical…
DEFF Research Database (Denmark)
Bugge, Anna; Hermansen, Bianca El-Naaman; Froberg, Karsten
13.35 yr in 7th grade). BMI, sum of 4 skinfolds (S4SF) and waist to hip ratio (WHR) were measured. PA was measured using CSA accelerometers for four consecutive days. Aerobic fitness (VO2max) was directly measured during a maximal progressive running test on a treadmill. Fasting intravenous blood...
2006-03-31
consuming, so easier, more efficient measures are often used. Body fat can be estimated by skinfold measures, waist-to-hip circumference ratios, or...of social interactions; and probably altered brain morphology such as cortical thickness and increased dendritic branching (based on archived
Yoneyama, Sachiko; Guo, Yiran; Lanktree, Matthew B.; Barnes, Michael R.; Elbers, Clara C.; Karczewski, Konrad J.; Padmanabhan, Sandosh; Bauer, Florianne; Baumert, Jens; Beitelshees, Amber; Berenson, Gerald S.; Boer, Jolanda M. A.; Burke, Gregory; Cade, Brian; Chen, Wei; Cooper-Dehoff, Rhonda M.; Gaunt, Tom R.; Gieger, Christian; Gong, Yan; Gorski, Mathias; Heard-Costa, Nancy; Johnson, Toby; Lamonte, Michael J.; Mcdonough, Caitrin; Monda, Keri L.; Onland-Moret, N. Charlotte; Nelson, Christopher P.; O'Connell, Jeffrey R.; Ordovas, Jose; Peter, Inga; Peters, Annette; Shaffer, Jonathan; Shen, Haiqinq; Smith, Erin; Speilotes, Liz; Thomas, Fridtjof; Thorand, Barbara; Verschuren, W. M. Monique; Anand, Sonia S.; Dominiczak, Anna; Davidson, Karina W.; Hegele, Robert A.; Heid, Iris; Hofker, Marten H.; Huggins, Gordon S.; Illig, Thomas; Johnson, Julie A.; Kirkland, Susan; Koenig, Wolfgang; Langaee, Taimour Y.; Mccaffery, Jeanne; Melander, Olle; Mitchell, Braxton D.; Munroe, Patricia; Murray, Sarah S.; Papanicolaou, George; Redline, Susan; Reilly, Muredach; Samani, Nilesh J.; Schork, Nicholas J.; Van der Schouw, Yvonne T.; Shimbo, Daichi; Shuldiner, Alan R.; Tobin, Martin D.; Wijmenga, Cisca; Yusuf, Salim; Hakonarson, Hakon; Lange, Leslie A.; Demerath, Ellen W.; Fox, Caroline S.; North, Kari E.; Reiner, Alex P.; Keating, Brendan; Taylor, Kira C.
2014-01-01
Waist circumference (WC) and waist-to-hip ratio (WHR) are surrogate measures of central adiposity that are associated with adverse cardiovascular events, type 2 diabetes and cancer independent of body mass index (BMI). WC and WHR are highly heritable with multiple susceptibility loci identified to d
Sports Participation, Anthropometric and Physiological Profiles of ...
African Journals Online (AJOL)
olayemitoyin
'Department of Sports and Exercise Science, Faculty of Allied Health Sciences, Kwame. Nkrumah ... Keywords: Body mass index; Waist-to- hip ratio; Body fat; Body water; Blood pressure; Heart rate ... Change in physical appearances is usually noticed ..... activity among children and adults: a review of ... Human Kinetics, UK.
Winkler, T.; Justice, A.E.; Graff, M.; Barata, L.; Feitosa, M.F.; Groot, de C.P.G.M.
2015-01-01
Genome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ substantially
T.W. Winkler (Thomas W.); A.E. Justice (Anne); M.J. Graff (Maud J.L.); Barata, L. (Llilda); M.F. Feitosa (Mary Furlan); Chu, S. (Su); J. Czajkowski (Jacek); T. Esko (Tõnu); M. Fall (Magnus); T.O. Kilpeläinen (Tuomas); Y. Lu (Yingchang); R. Mägi (Reedik); E. Mihailov (Evelin); T.H. Pers (Tune); Rüeger, S. (Sina); A. Teumer (Alexander); G.B. Ehret (Georg); T. Ferreira (Teresa); N.L. Heard-Costa (Nancy); J. Karjalainen (Juha); V. Lagou (Vasiliki); A. Mahajan (Anubha); Neinast, M.D. (Michael D.); I. Prokopenko (Inga); J. Simino (Jeannette); T.M. Teslovich (Tanya M.); R. Jansen; H.J. Westra (Harm-Jan); C.C. White (Charles); D. Absher (Devin); T.S. Ahluwalia (Tarunveer Singh); S. Ahmad (Shafqat); E. Albrecht (Eva); A.C. Alves (Alexessander Couto); Bragg-Gresham, J.L. (Jennifer L.); A.J. de Craen (Anton); J.C. Bis (Joshua); A. Bonnefond (Amélie); G. Boucher (Gabrielle); G. Cadby (Gemma); Y.-C. Cheng (Yu-Ching); Chiang, C.W. (Charleston W K); G. Delgado; A. Demirkan (Ayşe); N. Dueker (Nicole); N. Eklund (Niina); G. Eiriksdottir (Gudny); J. Eriksson (Joel); B. Feenstra (Bjarke); K. Fischer (Krista); F. Frau (Francesca); T.E. Galesloot (Tessel); F. Geller (Frank); A. Goel (Anuj); M. Gorski (Mathias); T.B. Grammer (Tanja); S. Gustafsson (Stefan); Haitjema, S. (Saskia); J.J. Hottenga (Jouke Jan); J.E. Huffman (Jennifer); A.U. Jackson (Anne); K.B. Jacobs (Kevin); A. Johansson (Åsa); M. Kaakinen (Marika); M.E. Kleber (Marcus); J. Lahti (Jari); I.M. Leach (Irene Mateo); Lehne, B. (Benjamin); Liu, Y. (Youfang); K.S. Lo; M. Lorentzon (Mattias); J. Luan (Jian'An); P.A. Madden (Pamela); M. Mangino (Massimo); B. McKnight (Barbara); Medina-Gomez, C. (Carolina); K.L. Monda (Keri); M.E. Montasser (May E.); G. Müller (Gabriele); M. Müller-Nurasyid (Martina); I.M. Nolte (Ilja); Panoutsopoulou, K. (Kalliope); L. Pascoe (Laura); L. Paternoster (Lavinia); N.W. Rayner (Nigel William); F. Renström (Frida); Rizzi, F. (Federica); L.M. Rose (Lynda); Ryan, K.A. (Kathy A.); P. Salo (Perttu); S. Sanna (Serena); H. Scharnagl (Hubert); Shi, J. (Jianxin); A.V. Smith (Albert Vernon); L. Southam (Lorraine); A. Stancáková (Alena); V. Steinthorsdottir (Valgerdur); R.J. Strawbridge (Rona); Sung, Y.J. (Yun Ju); I. Tachmazidou (Ioanna); T. Tanaka (Toshiko); G. Thorleifsson (Gudmar); S. Trompet (Stella); N. Pervjakova (Natalia); J.P. Tyrer (Jonathan); L. Vandenput (Liesbeth); S.W. Van Der Laan (Sander W.); N. van der Velde (Nathalie); J. van Setten (Jessica); J.V. van Vliet-Ostaptchouk (Jana); N. Verweij (Niek); E. Vlachopoulou (Efthymia); L. Waite (Lindsay); S.R. Wang (Sophie); Z. Wang (Zhaoming); S.H. Wild (Sarah); C. Willenborg (Christina); J.F. Wilson (James); A. Wong (Andrew); Yang, J. (Jian); L. Yengo (Loic); L.M. Yerges-Armstrong (Laura); Yu, L. (Lei); W. Zhang (Weihua); Zhao, J.H. (Jing Hua); E.A. Andersson (Ehm Astrid); S.J.L. Bakker (Stephan); D. Baldassarre (Damiano); Banasik, K. (Karina); Barcella, M. (Matteo); Barlassina, C. (Cristina); C. Bellis (Claire); P. Benaglio (Paola); J. Blangero (John); M. Blüher (Matthias); Bonnet, F. (Fabrice); L.L. Bonnycastle (Lori); H.A. Boyd (Heather); M. Bruinenberg (M.); Buchman, A.S. (Aron S.); H. Campbell (Harry); Y.D. Chen (Y.); P.S. Chines (Peter); S. Claudi-Boehm (Simone); J.W. Cole (John W.); F.S. Collins (Francis); E.J.C. de Geus (Eco); L.C.P.G.M. de Groot (Lisette); M. Dimitriou (Maria); J. Duan (Jubao); S. Enroth (Stefan); E. Eury (Elodie); A.-E. Farmaki (Aliki-Eleni); N.G. Forouhi (Nita); N. Friedrich (Nele); P.V. Gejman (Pablo); B. Gigante (Bruna); N. Glorioso (Nicola); A. Go (Attie); R.F. Gottesman (Rebecca); J. Gräßler (Jürgen); H. Grallert (Harald); N. Grarup (Niels); Gu, Y.-M. (Yu-Mei); L. Broer (Linda); A.C. Ham (Annelies); T. Hansen (T.); T.B. Harris (Tamara); C.A. Hartman (Catharina A.); Hassinen, M. (Maija); N. Hastie (Nick); A.T. Hattersley (Andrew); A.C. Heath (Andrew); A.K. Henders (Anjali); D.G. Hernandez (Dena); H.L. Hillege (Hans); O.L. Holmen (Oddgeir); G.K. Hovingh (Kees); J. Hui (Jennie); Husemoen, L.L. (Lise L.); Hutri-Kähönen, N. (Nina); P.G. Hysi (Pirro); T. Illig (Thomas); P.L. de Jager (Philip); S. Jalilzadeh (Shapour); T. Jorgensen (Torben); J.W. Jukema (Jan Wouter); Juonala, M. (Markus); S. Kanoni (Stavroula); M. Karaleftheri (Maria); K.T. Khaw; L. Kinnunen (Leena); T. Kittner (Thomas); W. Koenig (Wolfgang); I. Kolcic (Ivana); P. Kovacs (Peter); Krarup, N.T. (Nikolaj T.); W. Kratzer (Wolfgang); Krüger, J. (Janine); Kuh, D. (Diana); M. Kumari (Meena); T. Kyriakou (Theodosios); C. Langenberg (Claudia); L. Lannfelt (Lars); C. Lanzani (Chiara); V. Lotay (Vaneet); L.J. Launer (Lenore); K. Leander (Karin); J. Lindström (Jaana); A. Linneberg (Allan); Liu, Y.-P. (Yan-Ping); S. Lobbens (Stéphane); R.N. Luben (Robert); V. Lyssenko (Valeriya); S. Männistö (Satu); P.K. Magnusson (Patrik); W.L. McArdle (Wendy); C. Menni (Cristina); S. Merger (Sigrun); L. Milani (Lili); Montgomery, G.W. (Grant W.); A.P. Morris (Andrew); N. Narisu (Narisu); M. Nelis (Mari); K.K. Ong (Ken); A. Palotie (Aarno); L. Perusse (Louis); I. Pichler (Irene); M.G. Pilia (Maria Grazia); A. Pouta (Anneli); Rheinberger, M. (Myriam); Ribel-Madsen, R. (Rasmus); Richards, M. (Marcus); K.M. Rice (Kenneth); T.K. Rice (Treva K.); C. Rivolta (Carlo); V. Salomaa (Veikko); A.R. Sanders (Alan); M.A. Sarzynski (Mark A.); S. Scholtens (Salome); R.A. Scott (Robert); W.R. Scott (William R.); S. Sebert (Sylvain); S. Sengupta (Sebanti); B. Sennblad (Bengt); T. Seufferlein (Thomas); A. Silveira (Angela); P.E. Slagboom (Eline); J.H. Smit (Jan); T. Sparsø (Thomas); K. Stirrups (Kathy); R.P. Stolk (Ronald); H.M. Stringham (Heather); Swertz, M.A. (Morris A.); A.J. Swift (Amy); A.C. Syvänen; S.-T. Tan (Sian-Tsung); B. Thorand (Barbara); A. Tönjes (Anke); Tremblay, A. (Angelo); E. Tsafantakis (Emmanouil); P.J. van der Most (Peter); U. Völker (Uwe); M.-C. Vohl (Marie-Claude); J.M. Vonk (Judith); M. Waldenberger (Melanie); Walker, R.W. (Ryan W.); R. Wennauer (Roman); E. Widen; G.A.H.M. Willemsen (Gonneke); T. Wilsgaard (Tom); A.F. Wright (Alan); M.C. Zillikens (Carola); S. Van Dijk (Suzanne); N.M. van Schoor (Natasja); F.W. Asselbergs (Folkert); P.I.W. de Bakker (Paul); J.S. Beckmann (Jacques); J.P. Beilby (John); D.A. Bennett (David A.); R.N. Bergman (Richard); S.M. Bergmann (Sven); C.A. Böger (Carsten); B.O. Boehm (Bernhard); E.A. Boerwinkle (Eric); D.I. Boomsma (Dorret); S.R. Bornstein (Stefan); E.P. Bottinger (Erwin); C. Bouchard (Claude); J.C. Chambers (John); S.J. Chanock (Stephen); D.I. Chasman (Daniel); F. Cucca (Francesco); D. Cusi (Daniele); G.V. Dedoussis (George); J. Erdmann (Jeanette); K. Hagen (Knut); D. Evans; U. de Faire (Ulf); M. Farrall (Martin); L. Ferrucci (Luigi); I. Ford (Ian); L. Franke (Lude); P.W. Franks (Paul); P. Froguel (Philippe); R.T. Gansevoort (Ron); C. Gieger (Christian); H. Grönberg (Henrik); V. Gudnason (Vilmundur); U. Gyllensten (Ulf); P. Hall (Per); A. Hamsten (Anders); P. van der Harst (Pim); C. Hayward (Caroline); M. Heliovaara (Markku); C. Hengstenberg (Christian); A.A. Hicks (Andrew); A. Hingorani (Aroon); A. Hofman (Albert); Hu, F. (Frank); H.V. Huikuri (Heikki); K. Hveem (Kristian); A. James (Alan); Jordan, J.M. (Joanne M.); A. Jula (Antti); M. Kähönen (Mika); E. Kajantie (Eero); S. Kathiresan (Sekar); L.A.L.M. Kiemeney (Bart); M. Kivimaki (Mika); P. Knekt; H. Koistinen (Heikki); J.S. Kooner (Jaspal S.); S. Koskinen (Seppo); J. Kuusisto (Johanna); W. Maerz (Winfried); N.G. Martin (Nicholas); M. Laakso (Markku); T.A. Lakka (Timo); T. Lehtimäki (Terho); G. Lettre (Guillaume); D.F. Levinson (Douglas); W.H.L. Kao (Wen); M.L. Lokki; Mäntyselkä, P. (Pekka); M. Melbye (Mads); A. Metspalu (Andres); B.D. Mitchell (Braxton); F.L. Moll (Frans); J.C. Murray (Jeffrey); A.W. Musk (Arthur); M.S. Nieminen (Markku); I. Njølstad (Inger); C. Ohlsson (Claes); A.J. Oldehinkel (Albertine); B.A. Oostra (Ben); C. Palmer (Cameron); J.S. Pankow (James); G. Pasterkamp (Gerard); N.L. Pedersen (Nancy); O. Pedersen (Oluf); B.W.J.H. Penninx (Brenda); M. Perola (Markus); A. Peters (Annette); O. Polasek (Ozren); P.P. Pramstaller (Peter Paul); Psaty, B.M. (Bruce M.); Qi, L. (Lu); T. Quertermous (Thomas); Raitakari, O.T. (Olli T.); T. Rankinen (Tuomo); R. Rauramaa (Rainer); P.M. Ridker (Paul); J.D. Rioux (John); F. Rivadeneira Ramirez (Fernando); J.I. Rotter (Jerome I.); I. Rudan (Igor); H.M. den Ruijter (Hester ); J. Saltevo (Juha); N. Sattar (Naveed); Schunkert, H. (Heribert); P.E.H. Schwarz (Peter); A.R. Shuldiner (Alan); J. Sinisalo (Juha); H. Snieder (Harold); T.I.A. Sørensen (Thorkild); T.D. Spector (Timothy); Staessen, J.A. (Jan A.); Stefania, B. (Bandinelli); U. Thorsteinsdottir (Unnur); M. Stumvoll (Michael); J.-C. Tardif (Jean-Claude); E. Tremoli (Elena); J. Tuomilehto (Jaakko); A.G. Uitterlinden (André); M. Uusitupa (Matti); A.L.M. Verbeek; S.H.H.M. Vermeulen (Sita); J. Viikari (Jorma); Vitart, V. (Veronique); H. Völzke (Henry); P. Vollenweider (Peter); G. Waeber (Gérard); M. Walker (Mark); H. Wallaschofski (Henri); N.J. Wareham (Nick); H. Watkins (Hugh); E. Zeggini (Eleftheria); A. Chakravarti (Aravinda); Clegg, D.J. (Deborah J.); L.A. Cupples (Adrienne); P. Gordon-Larsen (Penny); C.E. Jaquish (Cashell); D.C. Rao (Dabeeru C.); Abecasis, G.R. (Goncalo R.); T.L. Assimes (Themistocles); I. Barroso (Inês); S.I. Berndt (Sonja); M. Boehnke (Michael); P. Deloukas (Panagiotis); C.S. Fox (Caroline); L. Groop (Leif); D. Hunter (David); E. Ingelsson (Erik); R.C. Kaplan (Robert); McCarthy, M.I. (Mark I.); K.L. Mohlke (Karen); J.R. O´Connell; Schlessinger, D. (David); D.P. Strachan (David); J-A. Zwart (John-Anker); C.M. van Duijn (Cock); J.N. Hirschhorn (Joel); C.M. Lindgren (Cecilia M.); I.M. Heid (Iris); K.E. North (Kari); I.B. Borecki (Ingrid); Z. Kutalik (Zoltán); R.J.F. Loos (Ruth)
2015-01-01
textabstractGenome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ
Multi-ethnic fine-mapping of 14 central adiposity loci
DEFF Research Database (Denmark)
Liu, Ching-Ti; Buchkovich, Martin L; Winkler, Thomas W;
2014-01-01
The Genetic Investigation of Anthropometric Traits (GIANT) consortium identified 14 loci in European Ancestry (EA) individuals associated with waist-to-hip ratio (WHR) adjusted for body mass index. These loci are wide and narrowing the signals remains necessary. Twelve of 14 loci identified in GI...
DEFF Research Database (Denmark)
Randall, Joshua C; Winkler, Thomas W; Kutalik, Zoltán
2013-01-01
Given the anthropometric differences between men and women and previous evidence of sex-difference in genetic effects, we conducted a genome-wide search for sexually dimorphic associations with height, weight, body mass index, waist circumference, hip circumference, and waist-to-hip-ratio (133,72...
Wormser, David; Kaptoge, Stephen; Di Angelantonio, Emanuele; Wood, Angela M.; Pennells, Lisa; Thompson, Alex; Sarwar, Nadeem; Kizer, Jorge R.; Lawlor, Debbie A.; Nordestgaard, Borge G.; Ridker, Paul; Salomaa, Veikko; Stevens, June; Woodward, Mark; Sattar, Naveed; Collins, Rory; Thompson, Simon G.; Whitlock, Gary; Danesh, John
2011-01-01
Background Guidelines differ about the value of assessment of adiposity measures for cardiovascular disease risk prediction when information is available for other risk factors. We studied the separate and combined associations of body-mass index (BMI), waist circumference, and waist-to-hip ratio wi
Zyriax, Birgit-Christiane; Schoeffauer, Mark; Klipstein-Grobusch, Kerstin; Boeing, Heiner; Windler, Eberhard
2011-01-01
Objective: The predictive value of weight gain, BMI, waist circumference (WC) and waist-to-hip ratio (WHR) as to cardiovascular risk factors and coronary heart disease (CHD) is still controversial. Methods: 200 consecutive pre- and postmenopausal women with incident CHD (cases) were compared with 25
Depressive Symptom Clusters Are Differentially Associated with General and Visceral Obesity
Marijnissen, Radboud M.; Bus, Boudewijn A. A.; Holewijn, Suzanne; Franke, Barbara; Purandare, Nitin; de Graaf, Jacqueline; den Heijer, Martin; Buitelaar, Jan K.; Voshaar, Richard C. Oude
2011-01-01
OBJECTIVES To examine the relationship between obesity and depressive symptoms taking into account different measures for obesity (body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR)) and different depressive symptom clusters. DESIGN Cross-sectional population-based survey.
DEFF Research Database (Denmark)
Wormser, David; Kaptoge, Stephen; Di Angelantonio, Emanuele
2011-01-01
Guidelines differ about the value of assessment of adiposity measures for cardiovascular disease risk prediction when information is available for other risk factors. We studied the separate and combined associations of body-mass index (BMI), waist circumference, and waist-to-hip ratio with risk...
Winkler, Thomas W.; Justice, Anne E.; Graff, Mariaelisa; Barata, Llilda; Feitosa, Mary F.; Chu, Su; Czajkowski, Jacek; Esko, Tonu; Fall, Tove; Kilpelainen, Tuomas O.; Lu, Yingchang; Magi, Reedik; Mihailov, Evelin; Pers, Tune H.; Rueeger, Sina; Teumer, Alexander; Ehret, Georg B.; Ferreira, Teresa; Heard-Costa, Nancy L.; Karjalainen, Juha; Lagou, Vasiliki; Mahajan, Anubha; Neinast, Michael D.; Prokopenko, Inga; Simino, Jeannette; Teslovich, Tanya M.; Jansen, Rick; Westra, Harm-Jan; White, Charles C.; Absher, Devin; Ahluwalia, Tarunveer S.; Ahmad, Shafqat; Albrecht, Eva; Alves, Alexessander Couto; Bragg-Gresham, Jennifer L.; de Craen, Anton J. M.; Bis, Joshua C.; Bonnefond, Amelie; Boucher, Gabrielle; Cadby, Gemma; Cheng, Yu-Ching; Chiang, Charleston W. K.; Delgado, Graciela; Demirkan, Ayse; Dueker, Nicole; Eklund, Niina; Eiriksdottir, Gudny; Eriksson, Joel; Feenstra, Bjarke; Fischer, Krista; Frau, Francesca; Galesloot, Tessel E.; Geller, Frank; Goel, Anuj; Gorski, Mathias; Grammer, Tanja B.; Gustafsson, Stefan; Haitjema, Saskia; Hottenga, Jouke-Jan; Huffman, Jennifer E.; Jackson, Anne U.; Jacobs, Kevin B.; Johansson, Asa; Kaakinen, Marika; Kleber, Marcus E.; Lahti, Jari; Leach, Irene Mateo; Lehne, Benjamin; Liu, Youfang; Lo, Ken Sin; Lorentzon, Mattias; Luan, Jian'an; Madden, Pamela A. F.; Mangino, Massimo; McKnight, Barbara; Medina-Gomez, Carolina; Monda, Keri L.; Montasser, May E.; Mueller, Gabriele; Mueller-Nurasyid, Martina; Nolte, Ilja M.; Panoutsopoulou, Kalliope; Pascoe, Laura; Paternoster, Lavinia; Rayner, Nigel W.; Renstrom, Frida; Rizzi, Federica; Rose, Lynda M.; Ryan, Kathy A.; Salo, Perttu; Sanna, Serena; Scharnagl, Hubert; Shi, Jianxin; Smith, Albert Vernon; Southam, Lorraine; Stancakova, Alena; Steinthorsdottir, Valgerdur; Strawbridge, Rona J.; Sung, Yun Ju; Tachmazidou, Ioanna; Tanaka, Toshiko; Thorleifsson, Gudmar; Trompet, Stella; Pervjakova, Natalia; Tyrer, Jonathan P.; Vandenput, Liesbeth; van der Laan, Sander W.; van der Velde, Nathalie; van Setten, Jessica; van Vliet-Ostaptchouk, Jana V.; Verweij, Niek; Vlachopoulou, Efthymia; Waite, Lindsay L.; Wang, Sophie R.; Wang, Zhaoming; Wild, Sarah H.; Willenborg, Christina; Wilson, James F.; Wong, Andrew; Yang, Jian; Yengo, Loic; Yerges-Armstrong, Laura M.; Yu, Lei; Zhang, Weihua; Zhao, Jing Hua; Andersson, Ehm A.; Bakker, Stephan J. L.; Baldassarre, Damiano; Banasik, Karina; Barcella, Matteo; Barlassina, Cristina; Bellis, Claire; Benaglio, Paola; Blangero, John; Blueher, Matthias; Bonnet, Fabrice; Bonnycastle, Lori L.; Boyd, Heather A.; Bruinenberg, Marcel; Buchman, Aron S.; Campbell, Harry; Chen, Yii-Der Ida; Chines, Peter S.; Claudi-Boehm, Simone; Cole, John; Collins, Francis S.; de Geus, Eco J. C.; de Groot, Lisette C. P. G. M.; Dimitriou, Maria; Duan, Jubao; Enroth, Stefan; Eury, Elodie; Farmaki, Aliki-Eleni; Forouhi, Nita G.; Friedrich, Nele; Gejman, Pablo V.; Gigante, Bruna; Glorioso, Nicola; Go, Alan S.; Gottesman, Omri; Graessler, Juergen; Grallert, Harald; Grarup, Niels; Gu, Yu-Mei; Broer, Linda; Ham, Annelies C.; Hansen, Torben; Harris, Tamara B.; Hartman, Catharina A.; Hassinen, Maija; Hastie, Nicholas; Hattersley, Andrew T.; Heath, Andrew C.; Henders, Anjali K.; Hernandez, Dena; Hillege, Hans; Holmen, Oddgeir; Hovingh, Kees G.; Hui, Jennie; Husemoen, Lise L.; Hutri-Kahonen, Nina; Hysi, Pirro G.; Illig, Thomas; De Jager, Philip L.; Jalilzadeh, Shapour; Jorgensen, Torben; Jukema, J. Wouter; Juonala, Markus; Kanoni, Stavroula; Karaleftheri, Maria; Khaw, Kay Tee; Kinnunen, Leena; Kittner, Steven J.; Koenig, Wolfgang; Kolcic, Ivana; Kovacs, Peter; Krarup, Nikolaj T.; Kratzer, Wolfgang; Krueger, Janine; Kuh, Diana; Kumari, Meena; Kyriakou, Theodosios; Langenberg, Claudia; Lannfelt, Lars; Lanzani, Chiara; Lotay, Vaneet; Launer, Lenore J.; Leander, Karin; Lindstrom, Jaana; Linneberg, Allan; Liu, Yan-Ping; Lobbens, Stephane; Luben, Robert; Lyssenko, Valeriya; Mannisto, Satu; Magnusson, Patrik K.; McArdle, Wendy L.; Menni, Cristina; Merger, Sigrun; Milani, Lili; Montgomery, Grant W.; Morris, Andrew P.; Narisu, Narisu; Nelis, Mari; Ong, Ken K.; Palotie, Aarno; Perusse, Louis; Pichler, Irene; Pilia, Maria G.; Pouta, Anneli; Rheinberger, Myriam; Ribel-Madsen, Rasmus; Richards, Marcus; Rice, Kenneth M.; Rice, Treva K.; Rivolta, Carlo; Salomaa, Veikko; Sanders, Alan R.; Sarzynski, Mark A.; Scholtens, Salome; Scott, Robert A.; Scott, William R.; Sebert, Sylvain; Sengupta, Sebanti; Sennblad, Bengt; Seufferlein, Thomas; Silveira, Angela; Slagboom, P. Eline; Smit, Jan H.; Sparso, Thomas H.; Stirrups, Kathleen; Stolk, Ronald P.; Stringham, Heather M.; Swertz, Morris A.; Swift, Amy J.; Syvanen, Ann-Christine; Tan, Sian-Tsung; Thorand, Barbara; Toenjes, Anke; Tremblay, Angelo; Tsafantakis, Emmanouil; van der Most, Peter J.; Voelker, Uwe; Vohl, Marie-Claude; Vonk, Judith M.; Waldenberger, Melanie; Walker, Ryan W.; Wennauer, Roman; Widen, Elisabeth; Willemsen, Gonneke; Wilsgaard, Tom; Wright, Alan F.; Zillikens, M. Carola; van Dijk, Suzanne C.; van Schoor, Natasja M.; Asselbergs, Folkert W.; de Bakker, Paul I. W.; Beckmann, Jacques S.; Beilby, John; Bennett, David A.; Bergman, Richard N.; Bergmann, Sven; Boeger, Carsten A.; Boehm, Bernhard O.; Boerwinkle, Eric; Boomsma, Dorret I.; Bornstein, Stefan R.; Bottinger, Erwin P.; Bouchard, Claude; Chambers, John C.; Chanock, Stephen J.; Chasman, Daniel I.; Cucca, Francesco; Cusi, Daniele; Dedoussis, George; Erdmann, Jeanette; Eriksson, Johan G.; Evans, Denis A.; de Faire, Ulf; Farrall, Martin; Ferrucci, Luigi; Ford, Ian; Franke, Lude; Franks, Paul W.; Froguel, Philippe; Gansevoort, Ron T.; Gieger, Christian; Gronberg, Henrik; Gudnason, Vilmundur; Gyllensten, Ulf; Hall, Per; Hamsten, Anders; van der Harst, Pim; Hayward, Caroline; Heliovaara, Markku; Hengstenberg, Christian; Hicks, Andrew A.; Hingorani, Aroon; Hofman, Albert; Hu, Frank; Huikuri, Heikki V.; Hveem, Kristian; James, Alan L.; Jordan, Joanne M.; Jula, Antti; Kaehoenen, Mika; Kajantie, Eero; Kathiresan, Sekar; Kiemeney, Lambertus A. L. M.; Kivimaki, Mika; Knekt, Paul B.; Koistinen, Heikki A.; Kooner, Jaspal S.; Koskinen, Seppo; Kuusisto, Johanna; Maerz, Winfried; Martin, Nicholas G.; Laakso, Markku; Lakka, Timo A.; Lehtimaki, Terho; Lettre, Guillaume; Levinson, Douglas F.; Lind, Lars; Lokki, Marja-Liisa; Mantyselka, Pekka; Melbye, Mads; Metspalu, Andres; Mitchell, Braxton D.; Moll, Frans L.; Murray, Jeffrey C.; Musk, Arthur W.; Nieminen, Markku S.; Njolstad, Inger; Ohlsson, Claes; Oldehinkel, Albertine J.; Oostra, Ben A.; Palmer, Lyle J.; Pankow, James S.; Pasterkamp, Gerard; Pedersen, Nancy L.; Pedersen, Oluf; Penninx, Brenda W.; Perola, Markus; Peters, Annette; Polasek, Ozren; Pramstaller, Peter P.; Psaty, Bruce M.; Qi, Lu; Quertermous, Thomas; Raitakari, Olli T.; Rankinen, Tuomo; Rauramaa, Rainer; Ridker, Paul M.; Rioux, John D.; Rivadeneira, Fernando; Rotter, Jerome I.; Rudan, Igor; den Ruijter, Hester M.; Saltevo, Juha; Sattar, Naveed; Schunkert, Heribert; Schwarz, Peter E. H.; Shuldiner, Alan R.; Sinisalo, Juha; Snieder, Harold; Sorensen, Thorkild I. A.; Spector, Tim D.; Staessen, Jan A.; Stefania, Bandinelli; Thorsteinsdottir, Unnur; Stumvoll, Michael; Tardif, Jean-Claude; Tremoli, Elena; Tuomilehto, Jaakko; Uitterlinden, Andre G.; Uusitupa, Matti; Verbeek, Andre L. M.; Vermeulen, Sita H.; Viikari, Jorma S.; Vitart, Veronique; Voelzke, Henry; Vollenweider, Peter; Waeber, Gerard; Walker, Mark; Wallaschofski, Henri; Wareham, Nicholas J.; Watkins, Hugh; Zeggini, Eleftheria; Chakravarti, Aravinda; Clegg, Deborah J.; Cupples, L. Adrienne; Gordon-Larsen, Penny; Jaquish, Cashell E.; Rao, D. C.; Abecasis, Goncalo R.; Assimes, Themistocles L.; Barroso, Ines; Berndt, Sonja I.; Boehnke, Michael; Deloukas, Panos; Fox, Caroline S.; Groop, Leif C.; Hunter, David J.; Ingelsson, Erik; Kaplan, Robert C.; McCarthy, Mark I.; Mohlke, Karen L.; O'Connell, Jeffrey R.; Schlessinger, David; Strachan, David P.; Stefansson, Kari; van Duijn, Cornelia M.; Hirschhorn, Joel N.; Lindgren, Cecilia M.; Heid, Iris M.; North, Kari E.; Borecki, Ingrid B.; Kutalik, Zoltan; Loos, Ruth J. F.
2015-01-01
Genome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ substantially
Randall, Joshua C; Winkler, Thomas W; Kutalik, Zoltán; Berndt, Sonja I; Jackson, Anne U; Monda, Keri L; Kilpeläinen, Tuomas O; Esko, Tõnu; Mägi, Reedik; Li, Shengxu; Workalemahu, Tsegaselassie; Feitosa, Mary F; Croteau-Chonka, Damien C; Day, Felix R; Fall, Tove; Ferreira, Teresa; Gustafsson, Stefan; Locke, Adam E; Mathieson, Iain; Scherag, Andre; Vedantam, Sailaja; Wood, Andrew R; Liang, Liming; Steinthorsdottir, Valgerdur; Thorleifsson, Gudmar; Dermitzakis, Emmanouil T; Dimas, Antigone S; Karpe, Fredrik; Min, Josine L; Nicholson, George; Clegg, Deborah J; Person, Thomas; Krohn, Jon P; Bauer, Sabrina; Buechler, Christa; Eisinger, Kristina; Bonnefond, Amélie; Froguel, Philippe; Hottenga, Jouke-Jan; Prokopenko, Inga; Waite, Lindsay L; Harris, Tamara B; Smith, Albert Vernon; Shuldiner, Alan R; McArdle, Wendy L; Caulfield, Mark J; Munroe, Patricia B; Grönberg, Henrik; Chen, Yii-Der Ida; Li, Guo; Beckmann, Jacques S; Johnson, Toby; Thorsteinsdottir, Unnur; Teder-Laving, Maris; Khaw, Kay-Tee; Wareham, Nicholas J; Zhao, Jing Hua; Amin, Najaf; Oostra, Ben A; Kraja, Aldi T; Province, Michael A; Cupples, L Adrienne; Heard-Costa, Nancy L; Kaprio, Jaakko; Ripatti, Samuli; Surakka, Ida; Collins, Francis S; Saramies, Jouko; Tuomilehto, Jaakko; Jula, Antti; Salomaa, Veikko; Erdmann, Jeanette; Hengstenberg, Christian; Loley, Christina; Schunkert, Heribert; Lamina, Claudia; Wichmann, H Erich; Albrecht, Eva; Gieger, Christian; Hicks, Andrew A; Johansson, Asa; Pramstaller, Peter P; Kathiresan, Sekar; Speliotes, Elizabeth K; Penninx, Brenda; Hartikainen, Anna-Liisa; Jarvelin, Marjo-Riitta; Gyllensten, Ulf; Boomsma, Dorret I; Campbell, Harry; Wilson, James F; Chanock, Stephen J; Farrall, Martin; Goel, Anuj; Medina-Gomez, Carolina; Rivadeneira, Fernando; Estrada, Karol; Uitterlinden, André G; Hofman, Albert; Zillikens, M Carola; den Heijer, Martin; Kiemeney, Lambertus A; Maschio, Andrea; Hall, Per; Tyrer, Jonathan; Teumer, Alexander; Völzke, Henry; Kovacs, Peter; Tönjes, Anke; Mangino, Massimo; Spector, Tim D; Hayward, Caroline; Rudan, Igor; Hall, Alistair S; Samani, Nilesh J; Attwood, Antony Paul; Sambrook, Jennifer G; Hung, Joseph; Palmer, Lyle J; Lokki, Marja-Liisa; Sinisalo, Juha; Boucher, Gabrielle; Huikuri, Heikki; Lorentzon, Mattias; Ohlsson, Claes; Eklund, Niina; Eriksson, Johan G; Barlassina, Cristina; Rivolta, Carlo; Nolte, Ilja M; Snieder, Harold; Van der Klauw, Melanie M; Van Vliet-Ostaptchouk, Jana V; Gejman, Pablo V; Shi, Jianxin; Jacobs, Kevin B; Wang, Zhaoming; Bakker, Stephan J L; Mateo Leach, Irene; Navis, Gerjan; van der Harst, Pim; Martin, Nicholas G; Medland, Sarah E; Montgomery, Grant W; Yang, Jian; Chasman, Daniel I; Ridker, Paul M; Rose, Lynda M; Lehtimäki, Terho; Raitakari, Olli; Absher, Devin; Iribarren, Carlos; Basart, Hanneke; Hovingh, Kees G; Hyppönen, Elina; Power, Chris; Anderson, Denise; Beilby, John P; Hui, Jennie; Jolley, Jennifer; Sager, Hendrik; Bornstein, Stefan R; Schwarz, Peter E H; Kristiansson, Kati; Perola, Markus; Lindström, Jaana; Swift, Amy J; Uusitupa, Matti; Atalay, Mustafa; Lakka, Timo A; Rauramaa, Rainer; Bolton, Jennifer L; Fowkes, Gerry; Fraser, Ross M; Price, Jackie F; Fischer, Krista; Krjutå Kov, Kaarel; Metspalu, Andres; Mihailov, Evelin; Langenberg, Claudia; Luan, Jian'an; Ong, Ken K; Chines, Peter S; Keinanen-Kiukaanniemi, Sirkka M; Saaristo, Timo E; Edkins, Sarah; Franks, Paul W; Hallmans, Göran; Shungin, Dmitry; Morris, Andrew David; Palmer, Colin N A; Erbel, Raimund; Moebus, Susanne; Nöthen, Markus M; Pechlivanis, Sonali; Hveem, Kristian; Narisu, Narisu; Hamsten, Anders; Humphries, Steve E; Strawbridge, Rona J; Tremoli, Elena; Grallert, Harald; Thorand, Barbara; Illig, Thomas; Koenig, Wolfgang; Müller-Nurasyid, Martina; Peters, Annette; Boehm, Bernhard O; Kleber, Marcus E; März, Winfried; Winkelmann, Bernhard R; Kuusisto, Johanna; Laakso, Markku; Arveiler, Dominique; Cesana, Giancarlo; Kuulasmaa, Kari; Virtamo, Jarmo; Yarnell, John W G; Kuh, Diana; Wong, Andrew; Lind, Lars; de Faire, Ulf; Gigante, Bruna; Magnusson, Patrik K E; Pedersen, Nancy L; Dedoussis, George; Dimitriou, Maria; Kolovou, Genovefa; Kanoni, Stavroula; Stirrups, Kathleen; Bonnycastle, Lori L; Njølstad, Inger; Wilsgaard, Tom; Ganna, Andrea; Rehnberg, Emil; Hingorani, Aroon; Kivimaki, Mika; Kumari, Meena; Assimes, Themistocles L; Barroso, Inês; Boehnke, Michael; Borecki, Ingrid B; Deloukas, Panos; Fox, Caroline S; Frayling, Timothy; Groop, Leif C; Haritunians, Talin; Hunter, David; Ingelsson, Erik; Kaplan, Robert; Mohlke, Karen L; O'Connell, Jeffrey R; Schlessinger, David; Strachan, David P; Stefansson, Kari; van Duijn, Cornelia M; Abecasis, Gonçalo R; McCarthy, Mark I; Hirschhorn, Joel N; Qi, Lu; Loos, Ruth J F; Lindgren, Cecilia M; North, Kari E; Heid, Iris M
2013-01-01
Given the anthropometric differences between men and women and previous evidence of sex-difference in genetic effects, we conducted a genome-wide search for sexually dimorphic associations with height, weight, body mass index, waist circumference, hip circumference, and waist-to-hip-ratio (133,723 i
Winkler, Thomas W; Justice, Anne E; Graff, Mariaelisa; Barata, Llilda; Feitosa, Mary F; Chu, Su; Czajkowski, Jacek; Esko, Tõnu; Fall, Tove; Kilpeläinen, Tuomas O; Lu, Yingchang; Mägi, Reedik; Mihailov, Evelin; Pers, Tune H; Rüeger, Sina; Teumer, Alexander; Ehret, Georg B; Ferreira, Teresa; Heard-Costa, Nancy L; Karjalainen, Juha; Lagou, Vasiliki; Mahajan, Anubha; Neinast, Michael D; Prokopenko, Inga; Simino, Jeannette; Teslovich, Tanya M; Jansen, Rick; Westra, Harm-Jan; White, Charles C; Absher, Devin; Ahluwalia, Tarunveer S; Ahmad, Shafqat; Albrecht, Eva; Alves, Alexessander Couto; Bragg-Gresham, Jennifer L; de Craen, Anton J M; Bis, Joshua C; Bonnefond, Amélie; Boucher, Gabrielle; Cadby, Gemma; Cheng, Yu-Ching; Chiang, Charleston W K; Delgado, Graciela; Demirkan, Ayse; Dueker, Nicole; Eklund, Niina; Eiriksdottir, Gudny; Eriksson, Joel; Feenstra, Bjarke; Fischer, Krista; Frau, Francesca; Galesloot, Tessel E; Geller, Frank; Goel, Anuj; Gorski, Mathias; Grammer, Tanja B; Gustafsson, Stefan; Haitjema, Saskia; Hottenga, Jouke-Jan; Huffman, Jennifer E; Jackson, Anne U; Jacobs, Kevin B; Johansson, Åsa; Kaakinen, Marika; Kleber, Marcus E; Lahti, Jari; Leach, Irene Mateo; Lehne, Benjamin; Liu, Youfang; Lo, Ken Sin; Lorentzon, Mattias; Luan, Jian'an; Madden, Pamela A F; Mangino, Massimo; McKnight, Barbara; Medina-Gomez, Carolina; Monda, Keri L; Montasser, May E; Müller, Gabriele; Müller-Nurasyid, Martina; Nolte, Ilja M; Panoutsopoulou, Kalliope; Pascoe, Laura; Paternoster, Lavinia; Rayner, Nigel W; Renström, Frida; Rizzi, Federica; Rose, Lynda M; Ryan, Kathy A; Salo, Perttu; Sanna, Serena; Scharnagl, Hubert; Shi, Jianxin; Smith, Albert Vernon; Southam, Lorraine; Stančáková, Alena; Steinthorsdottir, Valgerdur; Strawbridge, Rona J; Sung, Yun Ju; Tachmazidou, Ioanna; Tanaka, Toshiko; Thorleifsson, Gudmar; Trompet, Stella; Pervjakova, Natalia; Tyrer, Jonathan P; Vandenput, Liesbeth; van der Laan, Sander W; van der Velde, Nathalie; van Setten, Jessica; van Vliet-Ostaptchouk, Jana V; Verweij, Niek; Vlachopoulou, Efthymia; Waite, Lindsay L; Wang, Sophie R; Wang, Zhaoming; Wild, Sarah H; Willenborg, Christina; Wilson, James F; Wong, Andrew; Yang, Jian; Yengo, Loïc; Yerges-Armstrong, Laura M; Yu, Lei; Zhang, Weihua; Zhao, Jing Hua; Andersson, Ehm A; Bakker, Stephan J L; Baldassarre, Damiano; Banasik, Karina; Barcella, Matteo; Barlassina, Cristina; Bellis, Claire; Benaglio, Paola; Blangero, John; Blüher, Matthias; Bonnet, Fabrice; Bonnycastle, Lori L; Boyd, Heather A; Bruinenberg, Marcel; Buchman, Aron S; Campbell, Harry; Chen, Yii-Der Ida; Chines, Peter S; Claudi-Boehm, Simone; Cole, John; Collins, Francis S; de Geus, Eco J C; de Groot, Lisette C P G M; Dimitriou, Maria; Duan, Jubao; Enroth, Stefan; Eury, Elodie; Farmaki, Aliki-Eleni; Forouhi, Nita G; Friedrich, Nele; Gejman, Pablo V; Gigante, Bruna; Glorioso, Nicola; Go, Alan S; Gottesman, Omri; Gräßler, Jürgen; Grallert, Harald; Grarup, Niels; Gu, Yu-Mei; Broer, Linda; Ham, Annelies C; Hansen, Torben; Harris, Tamara B; Hartman, Catharina A; Hassinen, Maija; Hastie, Nicholas; Hattersley, Andrew T; Heath, Andrew C; Henders, Anjali K; Hernandez, Dena; Hillege, Hans; Holmen, Oddgeir; Hovingh, Kees G; Hui, Jennie; Husemoen, Lise L; Hutri-Kähönen, Nina; Hysi, Pirro G; Illig, Thomas; De Jager, Philip L; Jalilzadeh, Shapour; Jørgensen, Torben; Jukema, J Wouter; Juonala, Markus; Kanoni, Stavroula; Karaleftheri, Maria; Khaw, Kay Tee; Kinnunen, Leena; Kittner, Steven J; Koenig, Wolfgang; Kolcic, Ivana; Kovacs, Peter; Krarup, Nikolaj T; Kratzer, Wolfgang; Krüger, Janine; Kuh, Diana; Kumari, Meena; Kyriakou, Theodosios; Langenberg, Claudia; Lannfelt, Lars; Lanzani, Chiara; Lotay, Vaneet; Launer, Lenore J; Leander, Karin; Lindström, Jaana; Linneberg, Allan; Liu, Yan-Ping; Lobbens, Stéphane; Luben, Robert; Lyssenko, Valeriya; Männistö, Satu; Magnusson, Patrik K; McArdle, Wendy L; Menni, Cristina; Merger, Sigrun; Milani, Lili; Montgomery, Grant W; Morris, Andrew P; Narisu, Narisu; Nelis, Mari; Ong, Ken K; Palotie, Aarno; Pérusse, Louis; Pichler, Irene; Pilia, Maria G; Pouta, Anneli; Rheinberger, Myriam; Ribel-Madsen, Rasmus; Richards, Marcus; Rice, Kenneth M; Rice, Treva K; Rivolta, Carlo; Salomaa, Veikko; Sanders, Alan R; Sarzynski, Mark A; Scholtens, Salome; Scott, Robert A; Scott, William R; Sebert, Sylvain; Sengupta, Sebanti; Sennblad, Bengt; Seufferlein, Thomas; Silveira, Angela; Slagboom, P Eline; Smit, Jan H; Sparsø, Thomas H; Stirrups, Kathleen; Stolk, Ronald P; Stringham, Heather M; Swertz, Morris A; Swift, Amy J; Syvänen, Ann-Christine; Tan, Sian-Tsung; Thorand, Barbara; Tönjes, Anke; Tremblay, Angelo; Tsafantakis, Emmanouil; van der Most, Peter J; Völker, Uwe; Vohl, Marie-Claude; Vonk, Judith M; Waldenberger, Melanie; Walker, Ryan W; Wennauer, Roman; Widén, Elisabeth; Willemsen, Gonneke; Wilsgaard, Tom; Wright, Alan F; Zillikens, M Carola; van Dijk, Suzanne C; van Schoor, Natasja M; Asselbergs, Folkert W; de Bakker, Paul I W; Beckmann, Jacques S; Beilby, John; Bennett, David A; Bergman, Richard N; Bergmann, Sven; Böger, Carsten A; Boehm, Bernhard O; Boerwinkle, Eric; Boomsma, Dorret I; Bornstein, Stefan R; Bottinger, Erwin P; Bouchard, Claude; Chambers, John C; Chanock, Stephen J; Chasman, Daniel I; Cucca, Francesco; Cusi, Daniele; Dedoussis, George; Erdmann, Jeanette; Eriksson, Johan G; Evans, Denis A; de Faire, Ulf; Farrall, Martin; Ferrucci, Luigi; Ford, Ian; Franke, Lude; Franks, Paul W; Froguel, Philippe; Gansevoort, Ron T; Gieger, Christian; Grönberg, Henrik; Gudnason, Vilmundur; Gyllensten, Ulf; Hall, Per; Hamsten, Anders; van der Harst, Pim; Hayward, Caroline; Heliövaara, Markku; Hengstenberg, Christian; Hicks, Andrew A; Hingorani, Aroon; Hofman, Albert; Hu, Frank; Huikuri, Heikki V; Hveem, Kristian; James, Alan L; Jordan, Joanne M; Jula, Antti; Kähönen, Mika; Kajantie, Eero; Kathiresan, Sekar; Kiemeney, Lambertus A L M; Kivimaki, Mika; Knekt, Paul B; Koistinen, Heikki A; Kooner, Jaspal S; Koskinen, Seppo; Kuusisto, Johanna; Maerz, Winfried; Martin, Nicholas G; Laakso, Markku; Lakka, Timo A; Lehtimäki, Terho; Lettre, Guillaume; Levinson, Douglas F; Lind, Lars; Lokki, Marja-Liisa; Mäntyselkä, Pekka; Melbye, Mads; Metspalu, Andres; Mitchell, Braxton D; Moll, Frans L; Murray, Jeffrey C; Musk, Arthur W; Nieminen, Markku S; Njølstad, Inger; Ohlsson, Claes; Oldehinkel, Albertine J; Oostra, Ben A; Palmer, Lyle J; Pankow, James S; Pasterkamp, Gerard; Pedersen, Nancy L; Pedersen, Oluf; Penninx, Brenda W; Perola, Markus; Peters, Annette; Polašek, Ozren; Pramstaller, Peter P; Psaty, Bruce M; Qi, Lu; Quertermous, Thomas; Raitakari, Olli T; Rankinen, Tuomo; Rauramaa, Rainer; Ridker, Paul M; Rioux, John D; Rivadeneira, Fernando; Rotter, Jerome I; Rudan, Igor; den Ruijter, Hester M; Saltevo, Juha; Sattar, Naveed; Schunkert, Heribert; Schwarz, Peter E H; Shuldiner, Alan R; Sinisalo, Juha; Snieder, Harold; Sørensen, Thorkild I A; Spector, Tim D; Staessen, Jan A; Stefania, Bandinelli; Thorsteinsdottir, Unnur; Stumvoll, Michael; Tardif, Jean-Claude; Tremoli, Elena; Tuomilehto, Jaakko; Uitterlinden, André G; Uusitupa, Matti; Verbeek, André L M; Vermeulen, Sita H; Viikari, Jorma S; Vitart, Veronique; Völzke, Henry; Vollenweider, Peter; Waeber, Gérard; Walker, Mark; Wallaschofski, Henri; Wareham, Nicholas J; Watkins, Hugh; Zeggini, Eleftheria; Chakravarti, Aravinda; Clegg, Deborah J; Cupples, L Adrienne; Gordon-Larsen, Penny; Jaquish, Cashell E; Rao, D C; Abecasis, Goncalo R; Assimes, Themistocles L; Barroso, Inês; Berndt, Sonja I; Boehnke, Michael; Deloukas, Panos; Fox, Caroline S; Groop, Leif C; Hunter, David J; Ingelsson, Erik; Kaplan, Robert C; McCarthy, Mark I; Mohlke, Karen L; O'Connell, Jeffrey R; Schlessinger, David; Strachan, David P; Stefansson, Kari; van Duijn, Cornelia M; Hirschhorn, Joel N; Lindgren, Cecilia M; Heid, Iris M; North, Kari E; Borecki, Ingrid B; Kutalik, Zoltán; Loos, Ruth J F
2015-01-01
Genome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ substantially betw
Freisling, Heinz; Arnold, Melina; Soerjomataram, Isabelle; O'Doherty, Mark George; Ordóñez-Mena, José Manuel; Bamia, Christina; Kampman, Ellen; Leitzmann, Michael; Romieu, Isabelle; Kee, Frank
2017-01-01
Background:We evaluated the associations of anthropometric indicators of general obesity (body mass index, BMI), an established risk factor of various cancer, and body fat distribution (waist circumference, WC; hip circumference, HC; and waist-to-hip ratio, WHR), which may better reflect
Yoneyama, Sachiko; Guo, Yiran; Lanktree, Matthew B.; Barnes, Michael R.; Elbers, Clara C.; Karczewski, Konrad J.; Padmanabhan, Sandosh; Bauer, Florianne; Baumert, Jens; Beitelshees, Amber; Berenson, Gerald S.; Boer, Jolanda M. A.; Burke, Gregory; Cade, Brian; Chen, Wei; Cooper-Dehoff, Rhonda M.; Gaunt, Tom R.; Gieger, Christian; Gong, Yan; Gorski, Mathias; Heard-Costa, Nancy; Johnson, Toby; Lamonte, Michael J.; Mcdonough, Caitrin; Monda, Keri L.; Onland-Moret, N. Charlotte; Nelson, Christopher P.; O'Connell, Jeffrey R.; Ordovas, Jose; Peter, Inga; Peters, Annette; Shaffer, Jonathan; Shen, Haiqinq; Smith, Erin; Speilotes, Liz; Thomas, Fridtjof; Thorand, Barbara; Verschuren, W. M. Monique; Anand, Sonia S.; Dominiczak, Anna; Davidson, Karina W.; Hegele, Robert A.; Heid, Iris; Hofker, Marten H.; Huggins, Gordon S.; Illig, Thomas; Johnson, Julie A.; Kirkland, Susan; Koenig, Wolfgang; Langaee, Taimour Y.; Mccaffery, Jeanne; Melander, Olle; Mitchell, Braxton D.; Munroe, Patricia; Murray, Sarah S.; Papanicolaou, George; Redline, Susan; Reilly, Muredach; Samani, Nilesh J.; Schork, Nicholas J.; Van der Schouw, Yvonne T.; Shimbo, Daichi; Shuldiner, Alan R.; Tobin, Martin D.; Wijmenga, Cisca; Yusuf, Salim; Hakonarson, Hakon; Lange, Leslie A.; Demerath, Ellen W.; Fox, Caroline S.; North, Kari E.; Reiner, Alex P.; Keating, Brendan; Taylor, Kira C.
2014-01-01
Waist circumference (WC) and waist-to-hip ratio (WHR) are surrogate measures of central adiposity that are associated with adverse cardiovascular events, type 2 diabetes and cancer independent of body mass index (BMI). WC and WHR are highly heritable with multiple susceptibility loci identified to
The Influence of Age and Sex on Genetic Associations with Adult Body Size and Shape
DEFF Research Database (Denmark)
Winkler, Thomas W; Justice, Anne E; Graff, Mariaelisa
2015-01-01
Genome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ substantially b...
Niaura, RS; Stroud, LR; Todaro, J; Ward, KD; Spiro, A; Aldwin, C; Landsberg, L; Weiss, ST
2003-01-01
We examined relationships between repression, general maladjustment, body mass index (BMI), and waist-to-hip ratio (WHR). The participants were 1,081 healthy older men from the Normative Aging Study. Repression and General Maladjustment Scales of the Minnesota Multiphasic Personality Inventory were
Versey, H. Shellae; Kaplan, George A.
2012-01-01
Hostility may be related to risk factors for cardiovascular disease (CVD), such as blood pressure. However, the process by which hostility affects blood pressure is not fully understood. The current study sought to evaluate abdominal obesity (waist-to-hip ratio [WHR]) as a potential mediator and modifier of the relationship between cynical…
Yoneyama, Sachiko; Guo, Yiran; Lanktree, Matthew B.; Barnes, Michael R.; Elbers, Clara C.; Karczewski, Konrad J.; Padmanabhan, Sandosh; Bauer, Florianne; Baumert, Jens; Beitelshees, Amber; Berenson, Gerald S.; Boer, Jolanda M. A.; Burke, Gregory; Cade, Brian; Chen, Wei; Cooper-Dehoff, Rhonda M.; Gaunt, Tom R.; Gieger, Christian; Gong, Yan; Gorski, Mathias; Heard-Costa, Nancy; Johnson, Toby; Lamonte, Michael J.; Mcdonough, Caitrin; Monda, Keri L.; Onland-Moret, N. Charlotte; Nelson, Christopher P.; O'Connell, Jeffrey R.; Ordovas, Jose; Peter, Inga; Peters, Annette; Shaffer, Jonathan; Shen, Haiqinq; Smith, Erin; Speilotes, Liz; Thomas, Fridtjof; Thorand, Barbara; Verschuren, W. M. Monique; Anand, Sonia S.; Dominiczak, Anna; Davidson, Karina W.; Hegele, Robert A.; Heid, Iris; Hofker, Marten H.; Huggins, Gordon S.; Illig, Thomas; Johnson, Julie A.; Kirkland, Susan; Koenig, Wolfgang; Langaee, Taimour Y.; Mccaffery, Jeanne; Melander, Olle; Mitchell, Braxton D.; Munroe, Patricia; Murray, Sarah S.; Papanicolaou, George; Redline, Susan; Reilly, Muredach; Samani, Nilesh J.; Schork, Nicholas J.; Van der Schouw, Yvonne T.; Shimbo, Daichi; Shuldiner, Alan R.; Tobin, Martin D.; Wijmenga, Cisca; Yusuf, Salim; Hakonarson, Hakon; Lange, Leslie A.; Demerath, Ellen W.; Fox, Caroline S.; North, Kari E.; Reiner, Alex P.; Keating, Brendan; Taylor, Kira C.
2014-01-01
Waist circumference (WC) and waist-to-hip ratio (WHR) are surrogate measures of central adiposity that are associated with adverse cardiovascular events, type 2 diabetes and cancer independent of body mass index (BMI). WC and WHR are highly heritable with multiple susceptibility loci identified to d
Kwakernaak, Arjan J.; Zelle, Dorien M.; Bakker, Stephan J. L.; Navis, Gerjan
2013-01-01
Central distribution of body fat is associated with a higher risk of renal disease, but whether it is the distribution pattern or the overall excess weight that underlies this association is not well understood. Here, we studied the association between waist-to-hip ratio (WHR), which reflects centra
Randall, Joshua C; Winkler, Thomas W; Kutalik, Zoltán; Berndt, Sonja I; Jackson, Anne U; Monda, Keri L; Kilpeläinen, Tuomas O; Esko, Tõnu; Mägi, Reedik; Li, Shengxu; Workalemahu, Tsegaselassie; Feitosa, Mary F; Croteau-Chonka, Damien C; Day, Felix R; Fall, Tove; Ferreira, Teresa; Gustafsson, Stefan; Locke, Adam E; Mathieson, Iain; Scherag, Andre; Vedantam, Sailaja; Wood, Andrew R; Liang, Liming; Steinthorsdottir, Valgerdur; Thorleifsson, Gudmar; Dermitzakis, Emmanouil T; Dimas, Antigone S; Karpe, Fredrik; Min, Josine L; Nicholson, George; Clegg, Deborah J; Person, Thomas; Krohn, Jon P; Bauer, Sabrina; Buechler, Christa; Eisinger, Kristina; Bonnefond, Amélie; Froguel, Philippe; Hottenga, Jouke-Jan; Prokopenko, Inga; Waite, Lindsay L; Harris, Tamara B; Smith, Albert Vernon; Shuldiner, Alan R; McArdle, Wendy L; Caulfield, Mark J; Munroe, Patricia B; Grönberg, Henrik; Chen, Yii-Der Ida; Li, Guo; Beckmann, Jacques S; Johnson, Toby; Thorsteinsdottir, Unnur; Teder-Laving, Maris; Khaw, Kay-Tee; Wareham, Nicholas J; Zhao, Jing Hua; Amin, Najaf; Oostra, Ben A; Kraja, Aldi T; Province, Michael A; Cupples, L Adrienne; Heard-Costa, Nancy L; Kaprio, Jaakko; Ripatti, Samuli; Surakka, Ida; Collins, Francis S; Saramies, Jouko; Tuomilehto, Jaakko; Jula, Antti; Salomaa, Veikko; Erdmann, Jeanette; Hengstenberg, Christian; Loley, Christina; Schunkert, Heribert; Lamina, Claudia; Wichmann, H Erich; Albrecht, Eva; Gieger, Christian; Hicks, Andrew A; Johansson, Asa; Pramstaller, Peter P; Kathiresan, Sekar; Speliotes, Elizabeth K; Penninx, Brenda; Hartikainen, Anna-Liisa; Jarvelin, Marjo-Riitta; Gyllensten, Ulf; Boomsma, Dorret I; Campbell, Harry; Wilson, James F; Chanock, Stephen J; Farrall, Martin; Goel, Anuj; Medina-Gomez, Carolina; Rivadeneira, Fernando; Estrada, Karol; Uitterlinden, André G; Hofman, Albert; Zillikens, M Carola; den Heijer, Martin; Kiemeney, Lambertus A; Maschio, Andrea; Hall, Per; Tyrer, Jonathan; Teumer, Alexander; Völzke, Henry; Kovacs, Peter; Tönjes, Anke; Mangino, Massimo; Spector, Tim D; Hayward, Caroline; Rudan, Igor; Hall, Alistair S; Samani, Nilesh J; Attwood, Antony Paul; Sambrook, Jennifer G; Hung, Joseph; Palmer, Lyle J; Lokki, Marja-Liisa; Sinisalo, Juha; Boucher, Gabrielle; Huikuri, Heikki; Lorentzon, Mattias; Ohlsson, Claes; Eklund, Niina; Eriksson, Johan G; Barlassina, Cristina; Rivolta, Carlo; Nolte, Ilja M; Snieder, Harold; Van der Klauw, Melanie M; Van Vliet-Ostaptchouk, Jana V; Gejman, Pablo V; Shi, Jianxin; Jacobs, Kevin B; Wang, Zhaoming; Bakker, Stephan J L; Mateo Leach, Irene; Navis, Gerjan; van der Harst, Pim; Martin, Nicholas G; Medland, Sarah E; Montgomery, Grant W; Yang, Jian; Chasman, Daniel I; Ridker, Paul M; Rose, Lynda M; Lehtimäki, Terho; Raitakari, Olli; Absher, Devin; Iribarren, Carlos; Basart, Hanneke; Hovingh, Kees G; Hyppönen, Elina; Power, Chris; Anderson, Denise; Beilby, John P; Hui, Jennie; Jolley, Jennifer; Sager, Hendrik; Bornstein, Stefan R; Schwarz, Peter E H; Kristiansson, Kati; Perola, Markus; Lindström, Jaana; Swift, Amy J; Uusitupa, Matti; Atalay, Mustafa; Lakka, Timo A; Rauramaa, Rainer; Bolton, Jennifer L; Fowkes, Gerry; Fraser, Ross M; Price, Jackie F; Fischer, Krista; Krjutå Kov, Kaarel; Metspalu, Andres; Mihailov, Evelin; Langenberg, Claudia; Luan, Jian'an; Ong, Ken K; Chines, Peter S; Keinanen-Kiukaanniemi, Sirkka M; Saaristo, Timo E; Edkins, Sarah; Franks, Paul W; Hallmans, Göran; Shungin, Dmitry; Morris, Andrew David; Palmer, Colin N A; Erbel, Raimund; Moebus, Susanne; Nöthen, Markus M; Pechlivanis, Sonali; Hveem, Kristian; Narisu, Narisu; Hamsten, Anders; Humphries, Steve E; Strawbridge, Rona J; Tremoli, Elena; Grallert, Harald; Thorand, Barbara; Illig, Thomas; Koenig, Wolfgang; Müller-Nurasyid, Martina; Peters, Annette; Boehm, Bernhard O; Kleber, Marcus E; März, Winfried; Winkelmann, Bernhard R; Kuusisto, Johanna; Laakso, Markku; Arveiler, Dominique; Cesana, Giancarlo; Kuulasmaa, Kari; Virtamo, Jarmo; Yarnell, John W G; Kuh, Diana; Wong, Andrew; Lind, Lars; de Faire, Ulf; Gigante, Bruna; Magnusson, Patrik K E; Pedersen, Nancy L; Dedoussis, George; Dimitriou, Maria; Kolovou, Genovefa; Kanoni, Stavroula; Stirrups, Kathleen; Bonnycastle, Lori L; Njølstad, Inger; Wilsgaard, Tom; Ganna, Andrea; Rehnberg, Emil; Hingorani, Aroon; Kivimaki, Mika; Kumari, Meena; Assimes, Themistocles L; Barroso, Inês; Boehnke, Michael; Borecki, Ingrid B; Deloukas, Panos; Fox, Caroline S; Frayling, Timothy; Groop, Leif C; Haritunians, Talin; Hunter, David; Ingelsson, Erik; Kaplan, Robert; Mohlke, Karen L; O'Connell, Jeffrey R; Schlessinger, David; Strachan, David P; Stefansson, Kari; van Duijn, Cornelia M; Abecasis, Gonçalo R; McCarthy, Mark I; Hirschhorn, Joel N; Qi, Lu; Loos, Ruth J F; Lindgren, Cecilia M; North, Kari E; Heid, Iris M
Given the anthropometric differences between men and women and previous evidence of sex-difference in genetic effects, we conducted a genome-wide search for sexually dimorphic associations with height, weight, body mass index, waist circumference, hip circumference, and waist-to-hip-ratio (133,723
Institute of Scientific and Technical Information of China (English)
刘发平; 陈宪龙
2015-01-01
In the process of upward drift stoping with backfill in Baixiangshan iron mine,the roof-contacted effect is not perfect,the roof-contacted filling ratio of the mine is researched.The MIDAS /GTS finite element software is applied to analyze the stress condition of the first-step approach stope cemented pillars that have different roof-contacted filling ratio when the second-step approach stope are conducted. Besides that,the security and stability of the cemented pillars are evaluated,and the different roof-con-tacted filling ratios are analyzed in depth so as to determine the optimal roof-contacted filling ratio.when the second-step approach stope are conducted,the tensile safety coefficient of the first-step approach stope cemented pillars with 80%roof-contacted filling ratio is 2.03,the compressive strength factor of safety is 1.28,the synthesized safety coefficient is 1.60.The above research results can provide a brand-new di-rection for the other mines to improve the roof-contacted filling ratio scientifically.%为解决白象山铁矿在上向进路充填采矿过程中充填接顶效果不理想的问题，对该矿山的充填接顶率进行了研究。运用 MIDAS ／GTS 有限元软件模拟分析二步进路采场开采时，一步进路采场不同充填接顶率胶结矿柱受力状况，并对胶结矿柱安全稳定性进行评价，对不同充填接顶率进行分析，从而确定最佳充填接顶率。当二步进路采场开采时，一步进路采场80％充填接顶率胶结矿柱抗拉安全系数为2．03，抗压安全系数为1．28，综合安全系数为1．6，为该矿上向进路充填法的最佳充填接顶率。该研究为其他矿山科学提高充填接顶率提供了一种全新的指导方向。
Energy Technology Data Exchange (ETDEWEB)
Altug, Mehmet [Inonu Univ., Malatya (Turkey). Dept. of Machine and Metal Technologies
2016-11-01
The study examines the changes of the microstructural, mechanical and conductivity characteristics of the titanium alloy Ti6Al4 V as a result of heat treatment using wire electrical discharge machining, and their effect on machinability. By means of optical microscopy and scanning electron microscopy (SEM), analyses have been performed to determine various characteristics and additionally, microhardness and conductivity measurements have been conducted. Material removal rate (MRR) and wire wear ratio (WWR) values have been determined by using L18 Taguchi test design. The microstructures of the samples have been changed by thermal procedures. Results have been obtained by using the Grey relational analysis (GRA) optimization technique to solve the maximum MRR and minimum WWR values. The best (highest) MRR value is obtained from sample E which was water quenched in dual phase processing. The microstructure of this sample is composed of primary α and α' phases. The best (lowest) WWR value is obtained from sample A.
Institute of Scientific and Technical Information of China (English)
李升波; 徐少兵; 王文军; 成波
2015-01-01
The fuel consumption of ground vehicles in accelerating scenarios is significantly affected by how they are driven. This paper quantitatively studies the fuel optimal accelerating strategies for vehicles with discontinuous gear ratio under the optimal control framework. The identification of economical accelerating strategy is converted into a Bolza-typed optimal control problem (OCP), in which an equivalent fuel consumption index is proposed to eliminate the difference of accelerating distances. The converted OCP has discontinuous input, i. e. gear ratio of transmission, and nonlinear cost function and plant model, which naturally casts in the mixed-integer OCP. Considering the gear shifting rules of mechanical transmission, we transform the discontinuous OCP into multiple but interconnected continuous problems. The multiple-phase knotting technology combining Legendre pseudospectral discretization is used to obtain the optimal numerical solutions to gear position, gear shifting time, and engine torque. The mechanism of the fuel optimal accelerating strategy is analyzed, and the practical rules of gear shifting and acceleration selection are also summarized. The fuel benefit of the economical accelerating strategy is validated by simulations.%加速过程中,车辆的油耗与驾驶员的操作策略密切相关。本文通过最优控制方法定量化地研究了挡位离散型车辆的经济性加速策略。将加速策略的辨识构建为一个Bolza型最优控制问题(Optimal control problem, OCP),设计了考虑加速距离影响的经济性定量评价指标。该问题含有离散型控制变量,隶属于混合整型最优控制问题,且性能函数和状态方程呈现强非线性。为高效地求解该问题,结合变速器挡位切换规律,将该整型问题转化为多段光滑问题的协同优化,采用Legendre伪谱拼接法实现变速器挡位、换挡时机、发动机力矩的数值求解。解析分析了经济性加速策略的形成机
Optimal cut-off point of waist-to-height ratio for predicting metabolic syndrome%腰围身高比预测代谢综合征的切点研究
Institute of Scientific and Technical Information of China (English)
蒋建家; 张雅萍; 林振忠; 牟伦盼; 孙炳庆; 苏劲波
2015-01-01
Objective To investigate the relationship between waist-to-height ratio and metabolic syndrome,in order to identify the optimal cut-off point of waist-to-height ratio for predicting metabolic syndrome.Methods In this cross-sectional study,we recruited 343 people who received physical examination in First Hospital of Quanzhou between January 2012 and June 2014,and collected the information of their waist circumference,height,weight,blood pressure,laboratory test results (including fasting blood glucose,2-hour glucose after oral glucose tolerance test,triglyceride,high-density lipoprotein cholesterol) and visceral fat area assessed by computed tomography.Then a receiver operating characteristic (ROC) curve analysis was used to estimate the optimal cut-off points of waist-to-height ratio for the prediction of metabolic syndrome.Results Among the 343 people,there were 195 metabolic syndrome patients,the prevalence rate was 56.8％,which was 70.2％ in men (127/181) and 42.0％ in women (68/162).In ROC curve analysis,the area under the curve of waist-to-height ratio for the prediction of metabolic syndrome was 0.664 for men,and 0.673 for women.The optimal cut-off point of waist-to-height ratio for predicting metabolic syndrome was 0.543 0 (sensitivity 88.2％,specificity 44.4％) for men,and 0.568 3 (sensitivity 86.8％,specificity 46.8％).Conclusion The optimal cut-off point of waist-to-height ratio for predicting metabolic syndrome in Quanzhou population is 0.543 0 for men and 0.568 3 for women.%目的 研究腰围身高比与代谢综合征的关系,寻找腰围身高比预测代谢综合征的最佳切点.方法 采用横断面调查方法,纳入2012年1月至2014年6月在福建医科大学附属泉州第一医院进行体检的343名人员,体检项目包括腰围、身高、体质量、血压、实验室检查(包括空腹血糖、口服葡萄糖耐量试验2h血糖、三酰甘油、高密度脂蛋白胆固醇)、CT测定腹腔内脂肪面积.通过受试者工
Vasques, Ana Carolina J; Cassani, Roberta S L; Forti, Adriana C e; Vilela, Brunna S; Pareja, José Carlos; Tambascia, Marcos Antonio; Geloneze, Bruno
2015-01-01
Sagittal abdominal diameter (SAD) has been proposed as a surrogate marker of insulin resistance (IR). However, the utilization of SAD requires specific validation for each ethnicity. We aimed to investigate the potential use of SAD, compared with classical anthropometrical parameters, as a surrogate marker of IR and to establish the cutoff values of SAD for screening for IR. A multicenter population survey on metabolic disorders was conducted. A race-admixtured sample of 824 adult women was assessed. The anthropometric parameters included: BMI, waist circumference (WC), waist-to-hip ratio and SAD. IR was determined by a hyperglycemic clamp and the HOMA-IR index. After adjustments for age and total body fat mass, SAD (r = 0.23 and r = -0.70) and BMI (r = 0.20 and r = -0.71) were strongly correlated with the IR measured by the HOMA-IR index and the clamp, respectively (p < 0.001). In the ROC analysis, the optimal cutoff for SAD in women was 21.0 cm. The women with an increased SAD presented 3.2 (CI 95%: 2.1-5.0) more likelihood of having IR, assessed by the HOMA-IR index compared with those with normal SAD (p < 0.001); whereas women with elevated BMI and WC were 2.1 (95% CI: 1.4-3.3) and 2.8 (95% CI: 1.7-4.5) more likely to have IR (p < 0.001), respectively. No statistically significant results were found for waist-to-hip ratio. SAD can be a suitable surrogate marker of IR. Understanding and applying routine and simplified methods is essential because IR is associated with an increased risk of obesity-related diseases even in the presence of normal weight, slight overweight, as well as in obesity. Further prospective analysis will need to verify SAD as a determinant of clinical outcomes, such as type 2 diabetes and cardiovascular events, in the Brazilian population.
促进经济增长的中国政府最优债务率测算%Measure of China's Optimal Public Debt Ratio of Promoting Economic Growth
Institute of Scientific and Technical Information of China (English)
干伟明; 张涤新
2016-01-01
This article builds a cross period model to discuss the relationship between a nation's debt and its economic growth .Results of the theoretical analysis show that there is an inverted U-shaped relationship between a nation's debt and its economic growth, that is, under specific conditions, when a nation's debt ratio is below the optimal threshold , the debt in-crease has a promoting influence on the economic growth; on the contrary , when the debt ratio exceeds that threshold , the debt increase will just put constraints on the economic growth .Based on China's time series data, this article builds a regres-sion model to validate the inverted U-shaped relationship between public debt and economic growth , which finds that China's optimal public debt ratio of recent years is about 47%.The policy implication of the paper is that China's public debt is still within the optimal threshold , although in the long run China's public debt increasing space is limited , in the short run China's public debt definitely has increasing capacity for financial policy to bolster China 's slowing down economy .%通过构建跨期模型来探讨一国债务与经济增长的关系。理论分析表明，一国债务与经济增长之间存在倒U形关系，即在一定条件下，当一国的债务低于最优值时，提高债务对经济增长具有促进作用，而当债务超过这一最优值时，增加债务则对经济增长具有副作用。在理论分析的基础上，构建了线性时间序列模型，基于中国样本数据证实了中国政府债务与中国经济增长之间倒U形关系的存在，并测算出现阶段中国政府最优债务率约为47％。这一结论表明：中国政府债务目前尚处于合理范围，虽然长期来看中国政府债务的提升空间已不大，但短期内进一步提升的空间犹存，这为中国政府充分运用财政政策提升尚处于探底阶段的中国经济预留了政策空间。
Institute of Scientific and Technical Information of China (English)
廖炎平; 刘莉; 龙腾
2011-01-01
Forward- Swept wing (FSW) configuration provides a now direction for the aerodynamic configuration desigu of UAV benause its excellent aerodynamic characteristics. The Class-Shape function Transformation (CST) method is used to describe the parameterized airfoil geometry. The parameterized models for aerodynamic and stealthy performance of FSW are constructed. The aerodynamic analysis model of FSW is constructed by computational fluid dynamics method basod on N - S equations. Tbe stealthy performance analysis model of FSW is constructed by computational electromagnetics method based Method of Moments ( MoM ). The multi - objective aerodynamic and stealthy performance optimization method for FSW using Kriging model is presented. The Latin hypercube method is employed to get a set of sample points. The aerodynamic and stealthy perfomance Kriging models are built. The multi-objective aerodynamic and stealthy performance optimization of FSW is optimized by combining Pareto genetic algorithm with Krigthg model. The results of the investigation show that the constructed analysis models are reasonable and the presented multi- objective optimization design method is feasible ,which can improve the performance of large- aspect- ratio FSW and the efficiency of optimization effiectively.%前掠翼布局优越的气动性能为无人机气动布局设计提供了一条新的方向.采用CST方法对翼型几何外形进行参数化描述,实现前掠翼气动和隐身多学科优化设计模型的参数化描述.建立了基于N-S方程的计算流体力学方法的前掠翼气动分析模型和基于矩量法的计算电磁学方法的前掠翼隐身分析模型.提出了基于Kriging模型的前掠翼气动隐身多目标优化方法,采用拉丁超方试验设计方法获取样本点,建立前掠翼气动和隐身的Kriging代理模型.将Pareto多目标遗传算法与Kriging代理模型结合进行大展弦比前掠翼的气动隐身多目标优化设计.研究结果表
Nonlinear trading models through Sharpe Ratio maximization.
Choey, M; Weigend, A S
1997-08-01
While many trading strategies are based on price prediction, traders in financial markets are typically interested in optimizing risk-adjusted performance such as the Sharpe Ratio, rather than the price predictions themselves. This paper introduces an approach which generates a nonlinear strategy that explicitly maximizes the Sharpe Ratio. It is expressed as a neural network model whose output is the position size between a risky and a risk-free asset. The iterative parameter update rules are derived and compared to alternative approaches. The resulting trading strategy is evaluated and analyzed on both computer-generated data and real world data (DAX, the daily German equity index). Trading based on Sharpe Ratio maximization compares favorably to both profit optimization and probability matching (through cross-entropy optimization). The results show that the goal of optimizing out-of-sample risk-adjusted profit can indeed be achieved with this nonlinear approach.
Application of alternative anthropometric measurements to predict metabolic syndrome
Gul Sagun; Aytekin Oguz; Engin Karagoz; Arzu Ti?li Filizer; Gonca Tamer; Banu Mesci
2014-01-01
OBJECTIVE: The association between rarely used anthropometric measurements (e.g., mid-upper arm, forearm, and calf circumference) and metabolic syndrome has not been proven. The aim of this study was to assess whether mid-upper arm, forearm, calf, and waist circumferences, as well as waist/height ratio and waist-to-hip ratio, were associated with metabolic syndrome. METHODS: We enrolled 387 subjects (340 women, 47 men) who were admitted to the obesity outpatient department of Istanbul Meden...
Directory of Open Access Journals (Sweden)
Rafiza Abdul Razak
2015-05-01
Full Text Available This paper presents the mechanical function and characterization of an artificial lightweight geopolymer aggregate (ALGA using LUSI (Sidoarjo mud and alkaline activator as source materials. LUSI stands for LU-Lumpur and SI-Sidoarjo, meaning mud from Sidoarjo which erupted near the Banjarpanji-1 exploration well in Sidoarjo, East Java, Indonesia on 27 May 2006. The effect of NaOH molarity, LUSI mud/Alkaline activator (LM/AA ratio, and Na2SiO3/NaOH ratio to the ALGA are investigated at a sintering temperature of 950 °C. The results show that the optimum NaOH molarity found in this study is 12 M due to the highest strength (lowest AIV value of 15.79% with lower water absorption and specific gravity. The optimum LUSI mud/Alkaline activator (LM/AA ratio of 1.7 and the Na2SiO3/NaOH ratio of 0.4 gives the highest strength with AIV value of 15.42% with specific gravity of 1.10 g/cm3 and water absorption of 4.7%. The major synthesized crystalline phases were identified as sodalite, quartz and albite. Scanning Electron Microscope (SEM image showed more complete geopolymer matrix which contributes to highest strength of ALGA produced.
Razak, Rafiza Abdul; Abdullah, Mohd Mustafa Al Bakri; Hussin, Kamarudin; Ismail, Khairul Nizar; Hardjito, Djwantoro; Yahya, Zarina
2015-05-21
This paper presents the mechanical function and characterization of an artificial lightweight geopolymer aggregate (ALGA) using LUSI (Sidoarjo mud) and alkaline activator as source materials. LUSI stands for LU-Lumpur and SI-Sidoarjo, meaning mud from Sidoarjo which erupted near the Banjarpanji-1 exploration well in Sidoarjo, East Java, Indonesia on 27 May 2006. The effect of NaOH molarity, LUSI mud/Alkaline activator (LM/AA) ratio, and Na2SiO3/NaOH ratio to the ALGA are investigated at a sintering temperature of 950 °C. The results show that the optimum NaOH molarity found in this study is 12 M due to the highest strength (lowest AIV value) of 15.79% with lower water absorption and specific gravity. The optimum LUSI mud/Alkaline activator (LM/AA) ratio of 1.7 and the Na2SiO3/NaOH ratio of 0.4 gives the highest strength with AIV value of 15.42% with specific gravity of 1.10 g/cm3 and water absorption of 4.7%. The major synthesized crystalline phases were identified as sodalite, quartz and albite. Scanning Electron Microscope (SEM) image showed more complete geopolymer matrix which contributes to highest strength of ALGA produced.
Microalbuminuria and obesity: impact on cardiovascular disease and mortality
DEFF Research Database (Denmark)
Klausen, Klaus Peder; Parving, Hans-Henrik; Scharling, Henrik
2008-01-01
P>Objective Microalbuminuria and obesity are both associated with cardiovascular disease (CVD). The aim of this study was to determine the association between obesity (measured by body mass index, waist-to-hip ratio, waist circumference) and different levels of microalbuminuria. We also aimed...... factors were measured during the years 1992-1994 at the Copenhagen City Heart Study. End-points were registered until 1999-2000 with respect to CVD and until 2004 with respect to death. Results There was a strong association between microalbuminuria and obesity. Microalbuminuria and obesity had additive...... to determine the risk of death and CVD at different levels of microalbuminuria and obesity. Design Population-based observational study based on 2696 men and women, 30-70 years of age. Urinary albumin excretion (UAE), body mass index, waist-to-hip ratio, waist circumference and other cardiovascular risk...
Body shape and size depictions of African American women in JET magazine, 1953-2006.
Dawson-Andoh, Nana A; Gray, James J; Soto, José A; Parker, Scott
2011-01-01
Depictions of Caucasian women in the mainstream media have become increasingly thinner in size and straighter in shape. These changes may be inconsistent with the growing influence of African American beauty ideals, which research has established as more accepting of larger body sizes and more curvaceous body types than Caucasians. The present study looked at trends in the portrayal of African American women featured in JET magazine from 1953 to 2006. Beauty of the Week (BOW) images were collected and analyzed to examine body size (estimated by independent judges) and body shape (estimated by waist-to-hip ratio). We expected body sizes to increase and body shapes to become more curvaceous. Results revealed a rise in models' body size consistent with expectations, but an increase in waist-to-hip ratio, contrary to prediction. Our findings suggest that the African American feminine beauty ideal reflects both consistencies with and departures from mainstream cultural ideals.
Directory of Open Access Journals (Sweden)
Tănase Alin-Eliodor
2014-08-01
Full Text Available This article focuses on computing techniques starting from trial balance data regarding financial key ratios. There are presented activity, liquidity, solvency and profitability financial key ratios. It is presented a computing methodology in three steps based on a trial balance.
Collins, Mimi
1997-01-01
Explores how human resource professionals, with above average offer/acceptance ratios, streamline their recruitment efforts. Profiles company strategies with internships, internal promotion, cooperative education programs, and how to get candidates to accept offers. Also discusses how to use the offer/acceptance ratio as a measure of program…
Akkerman, J. W.
1982-01-01
New mechanism alters compression ratio of internal-combustion engine according to load so that engine operates at top fuel efficiency. Ordinary gasoline, diesel and gas engines with their fixed compression ratios are inefficient at partial load and at low-speed full load. Mechanism ensures engines operate as efficiently under these conditions as they do at highload and high speed.
Vasques A.C.J.; de Lima Rosado L.E.F.P.; Rosado G.P.; Ribeiro R.C.L.; Franceschini S.C.C.; Geloneze B.; Priore S.E.; De Oliveira D.R.
2009-01-01
Objective: To assess the ability of anthropometric and body composition indicators in identifying insulin resistance (IR), determining cut-off points for those showing the best efficacy. Method: 138 men were evaluated. Waist perimeter (WP), sagittal abdominal diameter (SAD), conicity index, body mass index (BMI), body fat percent, sagittal index, and the waist-to-height, waist-to-hip and waist-to-thigh ratios were determined. IR was assessed by the HOMA-IR index. Statistical analysis consiste...
Randall, J. C.; Winkler, T.W.; Kutalik, Z.; Berndt, S.I.; Jackson, A.U.; Monda, K.L.; Kilpelainen, T.O.; Esko, T; Magi, R.; Li, S.; Workalemahu, T; Feitosa,M. F.; Croteau-Chonka, D.C.; Day, F. R.; Fall, T.
2013-01-01
Given the anthropometric differences between men and women and previous evidence of sex-difference in genetic effects, we conducted a genome-wide search for sexually dimorphic associations with height, weight, body mass index, waist circumference, hip circumference, and waist-to-hip-ratio (133,723 individuals) and took forward 348 SNPs into follow-up (additional 137,052 individuals) in a total of 94 studies. Seven loci displayed significant sex-difference (FDR<5%), including four previousl...
Abdominal Obesity and Lung Cancer Risk: Systematic Review and Meta-Analysis of Prospective Studies
Khemayanto Hidayat; Xuan Du; Guochong Chen; Minhua Shi; Bimin Shi
2016-01-01
Several meta-analyses of observational studies have been performed to examine the association between general obesity, as measured by body mass index (BMI), and lung cancer. These meta-analyses suggest an inverse relation between high BMI and this cancer. In contrast to general obesity, abdominal obesity appears to play a role in the development of lung cancer. However, the association between abdominal obesity (as measured by waist circumference (WC) (BMI adjusted) and waist to hip ratio (WH...
Luo, J.; Margolis, K L.; Adami, H-O; LaCroix, A. (Andrea); Ye, W.
2008-01-01
A total of 138 503 women in the Women's Health Initiative in the United States were followed (for an average of 7.7 years) through 12 September 2005 to examine obesity, especially central obesity in relation to pancreatic cancer (n=251). Women in the highest quintile of waist-to-hip ratio had 70% (95% confidence interval 10–160%) excess risk of pancreatic cancer compared with women in the lowest quintile.
Sex Categorization among Preschool Children: Increasing Utilization of Sexually Dimorphic Cues
Johnson, Kerri L.; Lurye, Leah E.; Tassinary, Louis G.
2010-01-01
Two studies examined how children between ages 4 and 6 use body shape (i.e., the waist-to-hip-ratio [WHR]) for sex categorization. In Study 1 (N = 73), 5- and 6-year-olds, but not 4-year-olds, selected bodies with increasingly discrepant WHRs to be "most like a man" and "most like a woman." Similarly, sex category judgments made by 5- and…
The Metabolic Syndrome among Postmenopausal Women in Gorgan
Abdoljalal Marjani; Sedigheh Moghasemi
2012-01-01
Introduction. The present study aimed to assess the metabolic syndrome among postmenopausal women in Gorgan, Iran. Materials and Methods. The study was conducted on hundred postmenopausal women who were referred to the health centers in Gorgan. Metabolic syndrome was diagnosed using Adult Treatment Panel III (ATP III) guidelines. Results. The mean body mass index, waist circumference, hip, circumference waist-to-hip ratio, diastolic blood pressure, and triglyceride and fasting blood glucose l...
Wyer, J C; Salzinger, F H
1983-01-01
Many common management techniques have little use in managing a medical group practice. Ratio analysis, however, can easily be adapted to the group practice setting. Acting as broad-gauge indicators, financial ratios provide an early warning of potential problems and can be very useful in planning for future operations. The author has gathered a collection of financial ratios which were developed by participants at an education seminar presented for the Virginia Medical Group Management Association. Classified according to the human element, system component, and financial factor, the ratios provide a good sampling of measurements relevant to medical group practices and can serve as an example for custom-tailoring a ratio analysis system for your medical group.
Optimally Stopped Optimization
Vinci, Walter; Lidar, Daniel A.
2016-11-01
We combine the fields of heuristic optimization and optimal stopping. We propose a strategy for benchmarking randomized optimization algorithms that minimizes the expected total cost for obtaining a good solution with an optimal number of calls to the solver. To do so, rather than letting the objective function alone define a cost to be minimized, we introduce a further cost-per-call of the algorithm. We show that this problem can be formulated using optimal stopping theory. The expected cost is a flexible figure of merit for benchmarking probabilistic solvers that can be computed when the optimal solution is not known and that avoids the biases and arbitrariness that affect other measures. The optimal stopping formulation of benchmarking directly leads to a real-time optimal-utilization strategy for probabilistic optimizers with practical impact. We apply our formulation to benchmark simulated annealing on a class of maximum-2-satisfiability (MAX2SAT) problems. We also compare the performance of a D-Wave 2X quantum annealer to the Hamze-Freitas-Selby (HFS) solver, a specialized classical heuristic algorithm designed for low-tree-width graphs. On a set of frustrated-loop instances with planted solutions defined on up to N =1098 variables, the D-Wave device is 2 orders of magnitude faster than the HFS solver, and, modulo known caveats related to suboptimal annealing times, exhibits identical scaling with problem size.
Optimization and Optimal Control
Chinchuluun, Altannar; Enkhbat, Rentsen; Tseveendorj, Ider
2010-01-01
During the last four decades there has been a remarkable development in optimization and optimal control. Due to its wide variety of applications, many scientists and researchers have paid attention to fields of optimization and optimal control. A huge number of new theoretical, algorithmic, and computational results have been observed in the last few years. This book gives the latest advances, and due to the rapid development of these fields, there are no other recent publications on the same topics. Key features: Provides a collection of selected contributions giving a state-of-the-art accou
DEFF Research Database (Denmark)
Svendsen, Anders Jørgen; Holmskov, U; Bro, Peter
1995-01-01
hitherto unnoted differences between controls and patients with either rheumatoid arthritis or systemic lupus erythematosus. For this we use simple, but unconventional, graphic representations of the data, based on difference plots and ratio plots. Differences between patients with Burkitt's lymphoma...... and systemic lupus erythematosus from another previously published study (Macanovic, M. and Lachmann, P.J. (1979) Clin. Exp. Immunol. 38, 274) are also represented using ratio plots. Our observations indicate that analysis by regression analysis may often be misleading....
Institute of Scientific and Technical Information of China (English)
王闽申; 陈烜; 饶明; 陈智强; 林志
2016-01-01
为了解决频繁的LTE-CDMA20001xEV-DO重定向严重影响LTE用户感知体验的问题，对LTE-CDMA20001xEV-DO重定向比例异常、用户感知差等现象着手进行具体问题的原因定位和分析，采用对比分析的方法发现厂家间驻留和迁移参数配置存在不一致。通过实验及对参数优化前后的数据分析，验证了厂家互操作策略不同、参数设置不一致是导致互操作重定向比例异常的根本原因，并给出了LTE-CDMA20001xEV-DO互操作参数配置原则和建议。%In order to solve the problem of frequent LTE-CDMA2000 1xEV-DO redirection affecting the LTE user perception experience seriously. This article located and analyzed the cause for LTE-CDMA2000 1xEV-DO redirection rate anomaly as well as bad user perception experience. With the method of comparative analysis, the article discovered the inconsistent conifguration of reside and migration parameters between the different manufacturers. Through experiments and data analysis of parameters before and after optimization, various operation strategies and inconsistent conifguration of manufacturers were determined to be the fundamental cause for the anomaly, and principles of LTE-CDMA2000 1xEV-DO interoperability parameters conifguration and the suggestions were put forward.
Institute of Scientific and Technical Information of China (English)
ZHONG Chong Ke; ZHONG Xiao Yan; XU Tan; ZHANG Yong Hong
2016-01-01
ObjectiveWaist circumference, waist-to-hip ratio and waist-to-height ratio, which are the indicators or measures of abdominal adiposity, have long been hypothesized to increase therisk of stroke; yet evidence accumulated till date is not conclusive. Here, we conducted a dose-response meta-analysis to summarize evidences of the association between these measures of abdominal adiposity and the risk of stroke. MethodsPubMed and Web of Science databases were searched from inception to May 2015. Two investigators independently conducted the study selection and data extraction. Dose-response relationships were assessed by the generalized least squares trend estimation, while the summaryeffect estimates were evaluated by the use of fixed- or random-effect models. Subgroup and sensitivity analyses were performed to assess the potential sources of heterogeneity and the robustness of the pooled estimation. Publication biasof the literaturewas evaluated usingBegg’s and Egger’s test. ResultsAltogether 15 prospective cohort studies were identified in this study. The summary of relative risks (95% confidence intervals) of stroke for the highest versus the lowest categories was 1.28 (1.18-1.40) for waist circumference, 1.32 (1.21-1.44) for waist-to-hip ratio, and 1.49 (1.24-1.78) for waist-to-height ratio. For a 10-cm increase in waist circumference, the relative risk of stroke increased by 10%; for a 0.1-unit increase in waist-to-hip ratio, the relative risk increased by 16%; and for a 0.05-unit increase in waist-to-height ratio, the relative risk increased by 13%. There was evidence of a nonlinear association between waist-to-hip ratio and stroke risk,Pnonlinearity=0.028. ConclusionFindings from our meta-analysis indicated that waist circumference, waist-to-hip ratio, and waist-to-height ratio were positively associated with the risk of stroke, particularly ischemic stroke.
Directory of Open Access Journals (Sweden)
George Marsaglia
2006-05-01
Full Text Available This article extends and amplifies on results from a paper of over forty years ago. It provides software for evaluating the density and distribution functions of the ratio z/w for any two jointly normal variates z,w, and provides details on methods for transforming a general ratio z/w into a standard form, (a+x/(b+y , with x and y independent standard normal and a, b non-negative constants. It discusses handling general ratios when, in theory, none of the moments exist yet practical considerations suggest there should be approximations whose adequacy can be verified by means of the included software. These approximations show that many of the ratios of normal variates encountered in practice can themselves be taken as normally distributed. A practical rule is developed: If a < 2.256 and 4 < b then the ratio (a+x/(b+y is itself approximately normally distributed with mean μ = a/(1.01b − .2713 and variance 2 = (a2 + 1/(b2 + .108b − 3.795 − μ2.
Directory of Open Access Journals (Sweden)
George Marsaglia
2006-05-01
Full Text Available This article extends and amplifies on results from a paper of over forty years ago. It provides software for evaluating the density and distribution functions of the ratio z/w for any two jointly normal variates z,w, and provides details on methods for transforming a general ratio z/w into a standard form, (a+x/(b+y , with x and y independent standard normal and a, b non-negative constants. It discusses handling general ratios when, in theory, none of the moments exist yet practical considerations suggest there should be approximations whose adequacy can be verified by means of the included software. These approximations show that many of the ratios of normal variates encountered in practice can themselves be taken as normally distributed. A practical rule is developed: If a < 2.256 and 4 < b then the ratio (a+x/(b+y is itself approximately normally distributed with mean μ = a/(1.01b - .2713 and variance σ2 = (a2 + 1/(b2 + .108b - 3.795 μ2.
DEFF Research Database (Denmark)
Kjærgaard, Søren; Canudas-Romo, Vladimir
2017-01-01
, the prospective potential support ratio usually focuses on the current mortality schedule, or period life expectancy. Instead, in this paper we look at the actual mortality experienced by cohorts in a population, using cohort life tables. We analyse differences between the two perspectives using mortality models......, historical data, and forecasted data. Cohort life expectancy takes future mortality improvements into account, unlike period life expectancy, leading to a higher prospective potential support ratio. Our results indicate that using cohort instead of period life expectancy returns around 0.5 extra younger...
Htoo, J K; Zhu, C L; Huber, L; de Lange, C F M; Quant, A D; Kerr, B J; Cromwell, G L; Lindemann, M D
2014-08-01
Three 21-d experiments were conducted to determine the optimum standardized ileal digestible (SID) Ile:Lys ratio in 10- to 22-kg and 24- to 39-kg pigs. In Exp. 1, 144 Yorkshire pigs (initial BW = 10.2 kg) were assigned to 6 diets with 6 pens per treatment. Diets 1 to 5 were formulated to contain 5 graded SID Ile:Lys (44, 51, 57, 63, and 70%), 1.18% SID Leu, and 0.90% SID Lys (second limiting). Diet 6 (diet 5 with added Lys) was formulated (1.06% SID Lys) as a positive control. Pigs fed diet 6 had higher (P diet 5 (P diets 1 to 5. Final BW, ADG, and ADFI increased (linear and quadratic, P 0.10) by dietary Ile:Lys. Overall, ADG and ADFI were highest for pigs fed diet 2 (51% SID Ile:Lys). In Exp. 2, 216 Yorkshire pigs (initial BW = 9.6 kg) were assigned to 9 diets with 6 pens per treatment. Diets 1 to 4 contained 0.40, 0.47, 0.54, and 0.61% SID Ile, respectively, and 1.21% SID Lys; diets 5 to 8 contained 0.72, 0.84, 0.96, and 1.08% SID Lys, respectively, and 0.68% SID Ile. Diet 9 was high in both Ile and Lys (0.68% SID Ile and 1.21% SID Lys). All diets contained 1.21% SID Leu. The ADG and G:F increased (linear and quadratic, P diets 1 to 4 and 9). The ADG and G:F increased (linear, P diets 5 to 9). The PUN at d 21 decreased (linear, P Diets 1 to 5 were formulated to contain 5 graded SID Ile:Lys (39, 46, 53, 61, and 68%), 1.17% SID Leu, and 0.91% SID Lys (second limiting). Final BW and ADG increased (linear and quadratic, P diets containing nonexcess levels of Leu.
Miles, T. R.; Haslum, M. N.; Wheeler, T. J.
1998-01-01
A study involving 11,804 British children (age 10) found that when specified criteria for dyslexia were used, 269 children qualified as dyslexic. These included 223 boys and 46 girls, for a ratio of 4.51 to 1. Difficulties in interpreting these data are discussed and a defense of the criteria is provided. (Author/CR)
Directory of Open Access Journals (Sweden)
PO de Wet
2005-06-01
Full Text Available The rectilinear Steiner ratio was shown to be 3/2 by Hwang [Hwang FK, 1976, On Steiner minimal trees with rectilinear distance, SIAM Journal on Applied Mathematics, 30, pp. 104– 114.]. We use continuity and introduce restricted point sets to obtain an alternative, short and self-contained proof of this result.
A note on Youden's J and its cost ratio
Directory of Open Access Journals (Sweden)
Smits Niels
2010-09-01
Full Text Available Abstract Background The Youden index, the sum of sensitivity and specificity minus one, is an index used for setting optimal thresholds on medical tests. Discussion When using this index, one implicitly uses decision theory with a ratio of misclassification costs which is equal to one minus the prevalence proportion of the disease. It is doubtful whether this cost ratio truly represents the decision maker's preferences. Moreover, in populations with a different prevalence, a selected threshold is optimal with reference to a different cost ratio. Summary The Youden index is not a truly optimal decision rule for setting thresholds because its cost ratio varies with prevalence. Researchers should look into their cost ratio and employ it in a decision theoretic framework to obtain genuinely optimal thresholds.
Institute of Scientific and Technical Information of China (English)
李甍; 宋协法; 孙国祥; 马晓娜; 刘鹰
2015-01-01
Currently, intensive marine aquaculture has been widely adopted to obtain higher yields of aquatic food production. However, the effluent unfiltered wastewater, including organic and inorganic nitrogen and phosphorous can damage the physiology of farmed species and cause hyper-trophication of adjacent ecosystems. Using bivalve mollusc and macroalgae to purify wastewater before discharged is gaining extensive attention due to their cost effect and efficient features. The present study was conducted to investigate the effectiveness of an oyster-Gracilaria system. The study focused on the effects of Gracilaria lemaneiformisdensities and Crassostrea gigas toGracilaria lemaneiformis ratios. This experiment contained two parts. In the first part, four densities ofGracilaria (0.8, 1.6, 2.4 and 3.2 g/L) were set up. The results showed that all the four treatments had a low total ammonia nitrogen removal rate (less than 40%) before 48 h. However, treatments of 2.4 g/L and 3.2 g/L had a relative high TAN removal rate in 60 h (54.34% and 67.70%, respectively), 72 h (39.77% and 48.27%, respectively).Gracilaria of 1.6 g/L and 2.4 g/L removed relative more NO2-N in 6 h (56.64% and 55.26%), and in 12 h. In comparison, 2.4 g/L had a significant higher (P0.05) difference withGracilaria lemaneiformis of 2.4 g/L. Therefore, both oyster andGracilaria lemaneiformis had the best efficiency in treating wastewater at the density of 2.4 g/L (Oyster:Gracilaria=1:1).%水产养殖废水中含有大量的 N、P 等营养素，不加处理的排放将带来环境污染，通过养殖废水的资源化利用，可以保护环境，同时获得经济效益，促进水产养殖业可持续发展。该文研究了太平洋牡蛎（Crassostrea gigas）与龙须菜（Gracilaria lemaneiformis）处理大西洋鲑（Salmo salar）养殖废水的适宜养殖密度与数量配比。研究内容分为两部分：1）龙须菜试验。探讨不同龙须菜养殖密度（0.8、1.6、2.4和3.2 g/L）对大
Directory of Open Access Journals (Sweden)
Bae CY
2012-12-01
Full Text Available Chul-Young Bae,1 Young Gon Kang,2 Young-Sung Suh,3 Jee Hye Han,4 Sung-Soo Kim,5 Kyung Won Shim61MediAge Research Center, Seoul, Korea; 2Chaum Power Aging Center, College of Medicine, CHA University, Seoul, Korea; 3Health Promotion Center, Keimyung University Dongsam Medical Center, Daegu, Korea; 4Department of Family Medicine, College of Medicine, Eulji University, Seoul, Korea; 5Department of Family Medicine, College of Medicine, Chungnam National University, Daejeon, Korea; 6Department of Family Medicine, Ewha Womans University Mokdong Hospital, Ewha Womans University, Seoul, KoreaBackground: To date, no studies have attempted to estimate body shape biological age using clinical parameters associated with body composition for the purposes of examining a person's body shape based on their age.Objective: We examined the relations between clinical parameters associated with body composition and chronological age, and proposed a model for estimating the body shape biological age.Methods: The study was conducted in 243,778 subjects aged between 20 and 90 years who received a general medical checkup at health promotion centers at university and community hospitals in Korea from 2004 to 2011.Results: In men, the clinical parameters with the highest correlation to age included the waist-to-hip ratio (r = 0.786, P < 0.001, hip circumference (r = −0.448, P < 0.001, and height (r = −0.377, P < 0.001. In women, the clinical parameters with the highest correlation to age include the waist-to-hip ratio (r = 0.859, P < 0.001, waist circumference (r = 0.580, P < 0.001, and hip circumference (r = 0.520, P < 0.001. To estimate the optimal body shape biological age based on clinical parameters associated with body composition, we performed a multiple regression analysis. In a model estimating the body shape biological age, the coefficient of determination (R2 was 0.71 in men and 0.76 in women.Conclusion: Our model for estimating body shape biological age
Buskulic, Damir; De Bonis, I; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Odier, P; Pietrzyk, B; Ariztizabal, F; Chmeissani, M; Crespo, J M; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Gaitan, V; Martínez, M; Orteu, S; Pacheco, A; Padilla, C; Palla, Fabrizio; Pascual, A; Perlas, J A; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Farilla, A; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Natali, S; Nuzzo, S; Ranieri, A; Raso, G; Romano, F; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Engelhardt, A; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Jacobsen, R; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Markou, C; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Oest, T; Palazzi, P; Pater, J R; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wiedenmann, W; Wildish, T; Witzeling, W; Wotschack, J; Ajaltouni, Ziad J; Bardadin-Otwinowska, Maria; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rossignol, J M; Saadi, F; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Kyriakis, A; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Passalacqua, L; Rougé, A; Rumpf, M; Tanaka, R; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Delfino, M C; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Pepé-Altarelli, M; Dorris, S J; Halley, A W; ten Have, I; Knowles, I G; Lynch, J G; Morton, W T; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Smith, M G; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Braun, O; Geweniger, C; Graefe, G; Hanke, P; Hepp, V; Kluge, E E; Putzer, A; Rensch, B; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Colling, D J; Dornan, Peter J; Konstantinidis, N P; Moneta, L; Moutoussi, A; Nash, J; San Martin, G; Sedgbeer, J K; Stacey, A M; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Bowdery, C K; Brodbeck, T J; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Whelan, E P; Williams, M I; Galla, A; Greene, A M; Kleinknecht, K; Quast, G; Raab, J; Renk, B; Sander, H G; Wanke, R; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Thulasidas, M; Nicod, D; Payre, P; Rousseau, D; Talby, M; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Brown, D; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Jakobs, K; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Wolf, G; Alemany, R; Boucrot, J; Callot, O; Cordier, A; Courault, F; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Musolino, G; Nikolic, I A; Park, H J; Park, I C; Schune, M H; Simion, S; Veillet, J J; Videau, I; Abbaneo, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Triggiani, G; Vannini, C; Verdini, P G; Walsh, J; Betteridge, A P; Blair, G A; Bryant, L M; Cerutti, F; Gao, Y; Green, M G; Johnson, D L; Medcalf, T; Mir, L M; Perrodo, P; Strong, J A; Bertin, V; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Edwards, M; Maley, P; Norton, P R; Thompson, J C; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Beddall, A; Booth, C N; Boswell, R; Cartwright, S L; Combley, F; Dawson, I; Köksal, A; Letho, M; Newton, W M; Rankin, C; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Feigl, E; Grupen, Claus; Lutters, G; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Ragusa, F; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Bellantoni, L; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Harton, J L; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Schmitt, M; Scott, I J; Sharma, V; Turk, J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G
1996-01-01
From 64492 selected \\tau-pair events, produced at the Z^0 resonance, the measurement of the tau decays into hadrons from a global analysis using 1991, 1992 and 1993 ALEPH data is presented. Special emphasis is given to the reconstruction of photons and \\pi^0's, and the removal of fake photons. A detailed study of the systematics entering the \\pi^0 reconstruction is also given. A complete and consistent set of tau hadronic branching ratios is presented for 18 exclusive modes. Most measurements are more precise than the present world average. The new level of precision reached allows a stringent test of \\tau-\\mu universality in hadronic decays, g_\\tau/g_\\mu \\ = \\ 1.0013 \\ \\pm \\ 0.0095, and the first measurement of the vector and axial-vector contributions to the non-strange hadronic \\tau decay width: R_{\\tau ,V} \\ = \\ 1.788 \\ \\pm \\ 0.025 and R_{\\tau ,A} \\ = \\ 1.694 \\ \\pm \\ 0.027. The ratio (R_{\\tau ,V} - R_{\\tau ,A}) / (R_{\\tau ,V} + R_{\\tau ,A}), equal to (2.7 \\pm 1.3) \\ \\%, is a measure of the importance of Q...
Sex-ratio optimization with helpers at the nest
Pen, I.R.; Weissing, F.J.
2000-01-01
In many cooperatively breeding animals, offspring produced earlier in life assist their parents in raising subsequent broods. Such helping behaviour is often confined to offspring of one sex. Sex-allocation theory predicts that parents overproduce offspring of the helping sex, but the expected degre
Optimal Cross-Validation Split Ratio: Experimental Investigation
DEFF Research Database (Denmark)
Goutte, Cyril; Larsen, Jan
1998-01-01
Cross-validation is a common method for assessing the generalisation ability of a model in order to tune a regularisation parameter or otherhyper-parameters of a learning process. The use of cross-validation requires to set yet an additional parameter, the split rati. While a few texts haveinvest......Cross-validation is a common method for assessing the generalisation ability of a model in order to tune a regularisation parameter or otherhyper-parameters of a learning process. The use of cross-validation requires to set yet an additional parameter, the split rati. While a few texts...
Determining the Optimal C-130 Deployed Crew Ratio
2014-06-13
Flights Missions per Day: A count of the total number of missions launched from a location with a discreet mission number. Subsequent legs on the...the three flight times to render the total flight hours per discreet mission ID.for all legs are summed. After an initial review of the data, it was...will mathematically meet mission requirements in most plausible scenarios, less quantifiable factors would significantly increase the likelihood of
Sex-ratio optimization with helpers at the nest
Pen, I.R.; Weissing, F.J.
2000-01-01
In many cooperatively breeding animals, offspring produced earlier in life assist their parents in raising subsequent broods. Such helping behaviour is often confined to offspring of one sex. Sex-allocation theory predicts that parents overproduce offspring of the helping sex, but the expected
Directory of Open Access Journals (Sweden)
L. I. Rozonoer
1999-01-01
Full Text Available Necessary and sufficient conditions for existence of optimal control for all initial data are proved for LQ-optimization problem. If these conditions are fulfilled, necessary and sufficient conditions of optimality are formulated. Basing on the results, some general hypotheses on optimal control in terms of Pontryagin's maximum condition and Bellman's equation are proposed.
Lefever, A. E.
1982-01-01
Proposed arrangement of two connected planetary differentials results in gear ratio many times that obtainable in conventional series gear assembly of comparable size. Ratios of several thousand would present no special problems. Selection of many different ratios is available with substantially similar gear diameters. Very high gear ratios would be obtained from small mechanism.
Optimization Design for Digital Binoculars
Institute of Scientific and Technical Information of China (English)
CEN Jun-bo; CHEN Wei-min; LI Hui; HUANG Shang-lian
2005-01-01
In order to develop competitive and high performance/cost ratio of digital binoculars, design scheme should be optimized in term of technical capacity, economic benefit, product performance, risk management, etc. The common optimization method is limited in qualitative analysis, and the parameter optimization method is limited in obtaining optimal parameter only from technical side. Each method has its limitation. Based on the analysis of digital binoculars parameters, optional design schemes are laid down.Analytic hierarchy process combined the qualitative analysis with the quantitative analysis together. The design schemes are optimized, and result is worked out.
Assessing Readiness to Lose Weight among Obese Women Attending the Nutrition Clinic
Directory of Open Access Journals (Sweden)
Fatemeh Ghannadiasl
2014-07-01
Full Text Available Background: Assessing individual’s readiness to change and targeting the intervention to the level of readiness may improve successful weight loss rates. This study aimed to assess readiness for weight loss in obese women using the trans theoretical model. Methods: A cross-sectional study was conducted on 90 volunteer apparently healthy obese women, in Ardabil, Iran. Participants completed the translated and validated University of Rhode Island Change Assessment questionnaire in their first visit. Subjects were categorized into one of the stages of change based on the highest of four z-transformed scale scores. The readiness to change score was calculated. Results: More than half of the participants were in early stages of weight loss and 24.5% were in the action stage. The readiness score in the precontemplation stage was significantly lower than the other stages, but no significant difference was observed among the contemplation, action and maintenance stages. The significant correlation was observed between the stages of change and waist-to-hip ratio (r=0.33, P<0.05. Conclusion: Obese women attending the nutrition clinic are in different stages to change for weight loss. Understanding person specific stages of change orientates the dietitian to use the most appropriate counseling strategies. Hence the stages and readiness to change should be considered before implementing any intervention in clinical settings for optimal outcomes.
Numerical methods for stellarator optimization
Energy Technology Data Exchange (ETDEWEB)
Morris, R.N.; Hedrick, C.L.; Hirshman, S.P.; Lyon, J.F.; Rome, J.A.
1989-01-01
A numerical optimization procedure utilizing an inverse 3-D equilibrium solver, a Mercier stability assessment, a deeply-trapped-particle loss assessment, and a nonlinear optimization package has been used to produce low aspect ratio (A = 4) stellarator designs. These designs combine good stability and improved transport with a compact configuration. 7 refs., 2 figs., 1 tab.
Laird, Philip
1992-01-01
We distinguish static and dynamic optimization of programs: whereas static optimization modifies a program before runtime and is based only on its syntactical structure, dynamic optimization is based on the statistical properties of the input source and examples of program execution. Explanation-based generalization is a commonly used dynamic optimization method, but its effectiveness as a speedup-learning method is limited, in part because it fails to separate the learning process from the program transformation process. This paper describes a dynamic optimization technique called a learn-optimize cycle that first uses a learning element to uncover predictable patterns in the program execution and then uses an optimization algorithm to map these patterns into beneficial transformations. The technique has been used successfully for dynamic optimization of pure Prolog.
Schneider, Johannes J
2007-01-01
This book addresses stochastic optimization procedures in a broad manner. The first part offers an overview of relevant optimization philosophies; the second deals with benchmark problems in depth, by applying a selection of optimization procedures. Written primarily with scientists and students from the physical and engineering sciences in mind, this book addresses a larger community of all who wish to learn about stochastic optimization techniques and how to use them.
2015-07-06
consider a probabilistically-constrained portfolio optimization problem [16] to determine a minimum cost distribution of a unit investment among n assets...present a branching technique (Section 5). Through computational experiments on the probabilistic portfolio optimization problem (3) and an optimal ...at one. 15 DISTRIBUTION A: Distribution approved for public release. 6.2 Probabilistic Portfolio Optimization The first class of instances we test
Optimization Algorithms for Fully Automatic Optimizing Cross-cut Saw
Institute of Scientific and Technical Information of China (English)
LI Xiaochun; DING Qingxin; ZHAO Honglin; SUN Guangbin; XI Jiaxing
2010-01-01
The optimization of boards by grades plays an important role in the production for cross cutting boards, and the outturn rate and utilization of boards are directly affected by the optimization results of boards by grades. At present, the OptiCut series fully automatic optimizing cross-cut saw(FAOCCS) from Germany Weinig Group occupies the main markets in the world, but no report about the relative theories on the optimization technology and its algorithms is available. There exist some disadvantages in woodworking machinery and equipment used for cross cutting boards in China, for example, low sawing precision, outturn rate of boards and productivity, and difficulty in making statistics on the sawing results. Three optimization modes are presented for the optimization algorithms for FAOCCS, namely, optimization of fixed length, optimization of finger-jointed lumber and mixed optimization. Mathematical models are then established for these three optimization modes, and the corresponding software for realizing the optimization is prepared. Finally, Synthetic evaluation on the established mathematical models is presented through three practical examples. The results of synthetic evaluation indicate that FAOCCS using the optimization modes may raise the outturn rate of boards approximately 8% and the productivity obviously, and allows accurate statistics on the cross cut products of boards. The mathematical models of above three optimization modes are useful for increasing the outturn rate and utilization ratio of boards.
Directory of Open Access Journals (Sweden)
Tomas Ulitinas
2011-04-01
Full Text Available The article analyzes the task in truss height and in the optimization of the cross-sections of their elements. Element cross-sections are designed of steel profiles considering requirements for strength, stability and rigidity. A mathematical model is formulated as a nonlinear mathematical programming problem. It is solved as an iterative process, using mathematical software package “MATLAB” routine “fmincon”. The ratio of buckling is corrected in the each iteration. Optimization results are compared with those obtained applying software package “Robot Millennium”.Article in Lithuanian
Sex Ratio Elasticity Influences the Selection of Sex Ratio Strategy
Wang, Yaqiang; Wang, Ruiwu; Li, Yaotang; (Sam) Ma, Zhanshan
2016-01-01
There are three sex ratio strategies (SRS) in nature—male-biased sex ratio, female-biased sex ratio and, equal sex ratio. It was R. A. Fisher who first explained why most species in nature display a sex ratio of ½. Consequent SRS theories such as Hamilton’s local mate competition (LMC) and Clark’s local resource competition (LRC) separately explained the observed deviations from the seemingly universal 1:1 ratio. However, to the best of our knowledge, there is not yet a unified theory that accounts for the mechanisms of the three SRS. Here, we introduce the price elasticity theory in economics to define sex ratio elasticity (SRE), and present an analytical model that derives three SRSs based on the following assumption: simultaneously existing competitions for both resources A and resources B influence the level of SRE in both sexes differently. Consequently, it is the difference (between two sexes) in the level of their sex ratio elasticity that leads to three different SRS. Our analytical results demonstrate that the elasticity-based model not only reveals a highly plausible mechanism that explains the evolution of SRS in nature, but also offers a novel framework for unifying two major classical theories (i.e., LMC & LRC) in the field of SRS research. PMID:28009000
Sex Ratio Elasticity Influences the Selection of Sex Ratio Strategy
Wang, Yaqiang; Wang, Ruiwu; Li, Yaotang; (Sam) Ma, Zhanshan
2016-12-01
There are three sex ratio strategies (SRS) in nature—male-biased sex ratio, female-biased sex ratio and, equal sex ratio. It was R. A. Fisher who first explained why most species in nature display a sex ratio of ½. Consequent SRS theories such as Hamilton’s local mate competition (LMC) and Clark’s local resource competition (LRC) separately explained the observed deviations from the seemingly universal 1:1 ratio. However, to the best of our knowledge, there is not yet a unified theory that accounts for the mechanisms of the three SRS. Here, we introduce the price elasticity theory in economics to define sex ratio elasticity (SRE), and present an analytical model that derives three SRSs based on the following assumption: simultaneously existing competitions for both resources A and resources B influence the level of SRE in both sexes differently. Consequently, it is the difference (between two sexes) in the level of their sex ratio elasticity that leads to three different SRS. Our analytical results demonstrate that the elasticity-based model not only reveals a highly plausible mechanism that explains the evolution of SRS in nature, but also offers a novel framework for unifying two major classical theories (i.e., LMC & LRC) in the field of SRS research.
Ruszczynski, Andrzej
2011-01-01
Optimization is one of the most important areas of modern applied mathematics, with applications in fields from engineering and economics to finance, statistics, management science, and medicine. While many books have addressed its various aspects, Nonlinear Optimization is the first comprehensive treatment that will allow graduate students and researchers to understand its modern ideas, principles, and methods within a reasonable time, but without sacrificing mathematical precision. Andrzej Ruszczynski, a leading expert in the optimization of nonlinear stochastic systems, integrates t
Directory of Open Access Journals (Sweden)
James W Vaupel
Full Text Available Semelparous organisms have a simple life cycle characterized by immediate death after reproduction. We assume that semelparous life histories can be separated into a juvenile non-reproductive period followed by an adult period during which reproduction is possible. We derive formulae for the optimal age and size at reproduction and for the optimal size of the offspring (e.g., seeds. Our main contribution is to determine the conditions under which the optimal size of the offspring does not depend on the optimal size at reproduction and vice versa.
King, Andrew
2008-01-01
Remember when an optimized website was one that merely didn't take all day to appear? Times have changed. Today, website optimization can spell the difference between enterprise success and failure, and it takes a lot more know-how to achieve success. This book is a comprehensive guide to the tips, techniques, secrets, standards, and methods of website optimization. From increasing site traffic to maximizing leads, from revving up responsiveness to increasing navigability, from prospect retention to closing more sales, the world of 21st century website optimization is explored, exemplified a
On Quadratic Programming with a Ratio Objective
Bhaskara, Aditya; Manokaran, Rajsekar; Vijayaraghavan, Aravindan
2011-01-01
Quadratic Programming (QP) is the well-studied problem of maximizing over {-1,1} values the quadratic form \\sum_ij a_ij x_i x_j. QP captures many known combinatorial optimization problems and SDP techniques have given optimal approximation algorithms for many of these problems. We extend this body of work by initiating the study of Quadratic Programming problems where the variables take values in the domain {-1,0,1}. The specific problem we study is: QP-Ratio: max_{-1,0,1}^n (x^T A x) / (x^T x). This objective function is a natural relative of several well studied problems. Yet, it is a good testbed for both algorithms and complexity because the techniques used for quadratic problems for the {-1,1} and {0,1} domains do not seem to carry over to the {-1,0,1} domain. We give approximation algorithms and evidence for the hardness of approximating the QP-Ratio problem. We consider an SDP relaxation obtained by adding constraints to the natural SDP relaxation for this problem and obtain an O(n^{2/7}) algorithm for...
Costoiu, M.; Ioana, A.; Semenescu, A.; Marcu, D.
2016-11-01
The article presents the main advantages of electric arc furnace (EAF): it has a great contribution to reintroduce significant quantities of reusable metallic materials in the economic circuit, it constitutes itself as an important part in the Primary Materials and Energy Recovery (PMER), good productivity, good quality / price ratio, the possibility of developing a wide variety of classes and types of steels, including special steels and high alloy. In this paper it is presented some important developments of electric arc furnace: vacuum electric arc furnace, artificial intelligence expert systems for pollution control Steelworks. Another important aspect presented in the article is an original block diagram for optimization the EAF management system. This scheme is based on the original objective function (criterion function) represented by the price / quality ratio. The article presents an original block diagram for optimization the control system of the EAF. For designing this concept of EAF management system, many principles were used.
Institute of Scientific and Technical Information of China (English)
周晓容; 方玉; 刘鸿滨; 倪水芹; 何燕; 郑璇
2015-01-01
and explore the best indicator for predicting metabolic syndrome in the elderly. Method A cross-sectional study of 763 (406 men and 357 women) elderly people who participated in the annual health check-up was conducted. Clinical data of all participants were obtained including anthropometric parameters, body composition, lipid profiles, fasting blood glucose, and high sensitivity C-reactive protein. Receiver operating characteristic (ROC) curve was used to determine the optimal cutoff points for waist circumference, waist-to-hip ratio, waist-to-height ratio, percent body fat and fat mass index in relation to the area under the curve (AUC), sensitivity and specificity in the screening and prediction of metabolic syndrome. Result In total subjects, compared with non-metabolic syndrome group,the ROC curve analysis showed that parameters including waist circumference, waist-to-height ratio, waist-to-hip ratio, percent body fat and fat mass index had a significant potential for predicting metabolic syndrome (P<0.001). It was determined that waist circumference of 87.5 cm and 77.5 cm, waist-to-hip ratio of 0.89 and 0.87, waist-to-height ratio of 0.51 and 0.52, percent body fat of 24.1%and 31.7%and fat mass index of 5.00 kg/m2 and 7.80 kg/m2 were the optimal cutoff points for screening and predicting the presence of metabolic syndrome among men and women with a sensitivity of 81.3%,78.8%,87.5%, 51.3%and 83.8%(in men) and 85.1%,79.8%,71.3%, 70.2%and 80.9%(in women) and a specificity of 57.7%,62.6%,50.0%, 75.5%and 51.8%(in men) and 38.0%,53.2%,55.1%, 50.6%and 52.5% (in women),respectively. The area under the ROC curve (AUC) was 0.728, 0.755, 0.716, 0.671 and 0.725 in men and 0.652, 0.707, 0.658, 0.619 and 0.675 in women,respectively. Waist-to-hip ratio showed the highest AUC in all the parameters in men and women. Conclusion Anthropometric parameters and body composition analysis play important roles in the screening and prediction of metabolic syndrome, and waist-to-hip
United States current account deficits: a stochastic optimal control analysis
Stein, Jerome L.
2006-01-01
The "Pessimists" and the "Optimists" disagree whether the US external deficits and the associated buildup of US net foreign liabilities are problems that require urgent attention. A warning signal should be that the debt ratio deviates significantly from the optimal ratio. The optimal debt ratio or debt burden should take into account the vulnerability of consumption to shocks from the productivity of capital, the interest rate and exchange rate. The optimal debt ratio is derived from inter-t...
Deriving aerosol scattering ratio using range-resolved lidar ratio
Indian Academy of Sciences (India)
Reji K Dhaman; V Krishnakumar; V P Mahadevan Pillai; M Satyanarayana; K Raghunath
2014-02-01
The study on the optical characteristics of aerosol is carried out using the dual polarization lidar observations from the tropical inland station Gadanki (13.5°N, 79.2°E) for the period of observation during the year 2010. The summer and monsoon observation days show high scattering ratio at the tropical tropopause layer (TTL) and at the lower stratosphere region. The depolarization ratio is also high at this altitude due to the transport of particulates to the TTL layer by the active convection prevailing at the period. The study reveals more dependable values of scattering ratio that are seasonal and range-dependent.
Directory of Open Access Journals (Sweden)
Phillip M. Ligrani
1996-01-01
Full Text Available Experimental results are presented which describe the development and structure of flow downstream of a single row of holes with compound angle orientations producing film cooling at high blowing ratios. This film cooling configuration is important because similar arrangements are frequently employed on the first stage of rotating blades of operating gas turbine engines. With this configuration, holes are spaced 6d apart in the spanwise direction, with inclination angles of 24 degrees, and angles of orientation of 50.5 degrees. Blowing ratios range from 1.5 to 4.0 and the ratio of injectant to freestream density is near 1.0. Results show that spanwise averaged adiabatic effectiveness, spanwise-averaged iso-energetic Stanton number ratios, surveys of streamwise mean velocity, and surveys of injectant distributions change by important amounts as the blowing ratio increases. This is due to injectant lift-off from the test surface just downstream of the holes.
DEFF Research Database (Denmark)
Birkholm, Klavs
2010-01-01
En undersøgelse af anvendelsen af medicin til optimering af koncentration, hukommelse og følelsestonus. Efterfulgt af etiske overvejelser og anbefalinger til det politiske system......En undersøgelse af anvendelsen af medicin til optimering af koncentration, hukommelse og følelsestonus. Efterfulgt af etiske overvejelser og anbefalinger til det politiske system...
DEFF Research Database (Denmark)
A. Kristensen, Anders Schmidt; Damkilde, Lars
2007-01-01
. A way to solve the initial design problem namely finding a form can be solved by so-called topology optimization. The idea is to define a design region and an amount of material. The loads and supports are also fidefined, and the algorithm finds the optimal material distribution. The objective function...... dictates the form, and the designer can choose e.g. maximum stiness, maximum allowable stresses or maximum lowest eigenfrequency. The result of the topology optimization is a relatively coarse map of material layout. This design can be transferred to a CAD system and given the necessary geometrically...... refinements, and then remeshed and reanalysed in other to secure that the design requirements are met correctly. The output of standard topology optimization has seldom well-defined, sharp contours leaving the designer with a tedious interpretation, which often results in less optimal structures. In the paper...
Carver, Charles S.; Scheier, Michael F.
2014-01-01
Optimism is a cognitive construct (expectancies regarding future outcomes) that also relates to motivation: optimistic people exert effort, whereas pessimistic people disengage from effort. Study of optimism began largely in health contexts, finding positive associations between optimism and markers of better psychological and physical health. Physical health effects likely occur through differences in both health-promoting behaviors and physiological concomitants of coping. Recently, the scientific study of optimism has extended to the realm of social relations: new evidence indicates that optimists have better social connections, partly because they work harder at them. In this review, we examine the myriad ways this trait can benefit an individual, and our current understanding of the biological basis of optimism. PMID:24630971
Trace Ratio Criterion for Feature Extraction in Classification
Directory of Open Access Journals (Sweden)
Guoqi Li
2014-01-01
Full Text Available A generalized linear discriminant analysis based on trace ratio criterion algorithm (GLDA-TRA is derived to extract features for classification. With the proposed GLDA-TRA, a set of orthogonal features can be extracted in succession. Each newly extracted feature is the optimal feature that maximizes the trace ratio criterion function in the subspace orthogonal to the space spanned by the previous extracted features.
Critical Concentration Ratio for Solar Thermoelectric Generators
ur Rehman, Naveed; Siddiqui, Mubashir Ali
2016-10-01
A correlation for determining the critical concentration ratio (CCR) of solar concentrated thermoelectric generators (SCTEGs) has been established, and the significance of the contributing parameters is discussed in detail. For any SCTEG, higher concentration ratio leads to higher temperatures at the hot side of modules. However, the maximum value of this temperature for safe operation is limited by the material properties of the modules and should be considered as an important design constraint. Taking into account this limitation, the CCR can be defined as the maximum concentration ratio usable for a particular SCTEG. The established correlation is based on factors associated with the material and geometric properties of modules, thermal characteristics of the receiver, installation site attributes, and thermal and electrical operating conditions. To reduce the number of terms in the correlation, these factors are combined to form dimensionless groups by applying the Buckingham Pi theorem. A correlation model containing these groups is proposed and fit to a dataset obtained by simulating a thermodynamic (physical) model over sampled values acquired by applying the Latin hypercube sampling (LHS) technique over a realistic distribution of factors. The coefficient of determination and relative error are found to be 97% and ±20%, respectively. The correlation is validated by comparing the predicted results with literature values. In addition, the significance and effects of the Pi groups on the CCR are evaluated and thoroughly discussed. This study will lead to a wide range of opportunities regarding design and optimization of SCTEGs.
Injection molding of high aspect ratio sub-100 nm nanostructures
DEFF Research Database (Denmark)
Matschuk, Maria; Larsen, Niels B
2013-01-01
with FDTS. Reduced adhesion forces are consistent with lowered friction that reduces the risk of fracturing the nanoscopic pillars during demolding. Optimized mold surface chemistry and associated injection molding conditions permitted the fabrication of square arrays of 40 nm wide and 107 nm high (aspect......We have explored the use of mold coatings and optimized processing conditions to injection mold high aspect ratio nanostructures (height-to-width >1) in cyclic olefin copolymer (COC). Optimizing the molding parameters on uncoated nickel molds resulted in slight improvements in replication quality...
Moloud Payab; Roya Kelishadi; Mostafa Qorbani; Mohammad Esmaeil Motlagh; Shirin Hasani Ranjbar; Gelayol Ardalan; Hoda Zahedi; Mohammad Chinian; Hamid Asayesh; Bagher Larijani; Ramin Heshmat
2015-01-01
OBJECTIVE: This study aimed to evaluate the association of junk food consumption with hypertension and obesity in a national sample of Iranian children and adolescents. METHODS: This nationwide study was conducted in 2011-2012 among 14,880 students, aged 6-18 years, selected by cluster sampling from 30 provinces. Weight, height, waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), as well as systolic and diastolic blood pressure (BP) were m...
Moloud Payab; Roya Kelishadi; Mostafa Qorbani; Mohammad Esmaeil Motlagh; Shirin Hasani Ranjbar; Gelayol Ardalan; Hoda Zahedi; Mohammad Chinian; Hamid Asayesh; Bagher Larijani; Ramin Heshmat
2015-01-01
OBJECTIVE: This study aimed to evaluate the association of junk food consumption with hypertension and obesity in a national sample of Iranian children and adolescents. METHODS: This nationwide study was conducted in 2011-2012 among 14,880 students, aged 6-18 years, selected by cluster sampling from 30 provinces. Weight, height, waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), as well as systolic and diastolic blood pressure (BP) were m...
Modeling and Optimization of Cement Raw Materials Blending Process
Directory of Open Access Journals (Sweden)
Xianhong Li
2012-01-01
Full Text Available This paper focuses on modelling and solving the ingredient ratio optimization problem in cement raw material blending process. A general nonlinear time-varying (G-NLTV model is established for cement raw material blending process via considering chemical composition, feed flow fluctuation, and various craft and production constraints. Different objective functions are presented to acquire optimal ingredient ratios under various production requirements. The ingredient ratio optimization problem is transformed into discrete-time single objective or multiple objectives rolling nonlinear constraint optimization problem. A framework of grid interior point method is presented to solve the rolling nonlinear constraint optimization problem. Based on MATLAB-GUI platform, the corresponding ingredient ratio software is devised to obtain optimal ingredient ratio. Finally, several numerical examples are presented to study and solve ingredient ratio optimization problems.
Carbon Monoxide Mixing Ratio System
Oak Ridge National Laboratory — The Southern Great Plains (SGP) Carbon Monoxide (CO) system provides high-precision atmospheric concentration measurements of CO mixing ratio (ppbv dry air) every 10...
Pressure Ratio to Thermal Environments
Lopez, Pedro; Wang, Winston
2012-01-01
A pressure ratio to thermal environments (PRatTlE.pl) program is a Perl language code that estimates heating at requested body point locations by scaling the heating at a reference location times a pressure ratio factor. The pressure ratio factor is the ratio of the local pressure at the reference point and the requested point from CFD (computational fluid dynamics) solutions. This innovation provides pressure ratio-based thermal environments in an automated and traceable method. Previously, the pressure ratio methodology was implemented via a Microsoft Excel spreadsheet and macro scripts. PRatTlE is able to calculate heating environments for 150 body points in less than two minutes. PRatTlE is coded in Perl programming language, is command-line-driven, and has been successfully executed on both the HP and Linux platforms. It supports multiple concurrent runs. PRatTlE contains error trapping and input file format verification, which allows clear visibility into the input data structure and intermediate calculations.
Optimum Design of 1st Gear Ratio for 4WD Vehicles Based on Vehicle Dynamic Behaviour
M. H. Shojaeefard; Talebitooti,R.; Sadegh Yarmohammadi Satri
2013-01-01
This paper presents an approach that allows optimizing gear ratio and vehicle dimension to achieve optimum gear transmission. Therefore, augmented Lagrangian multiplier method, defined as classical method, is utilized to find the optimum gear ratios and the corresponding number of gear teeth applied to all epicyclical gears. The new method is able to calculate and also to optimize the gear ratio based on dynamics of 4WD vehicles. Therefore, 4WD vehicles dynamic equations are employed assuming...
Anderson Marliere NAVARRO; Michele Sun STEDILLE; de Unamuno, Maria do Rosário Del Lama; MARCHINI,Júlio Sérgio
2001-01-01
O objetivo deste trabalho foi avaliar a distribuição de gordura corporal, visceral e não visceral, em pacientes internados, medida por meio da antropometria. Foram avaliados 157 pacientes internados, distribuídos em dois grupos: Grupo I (95 pacientes portadores de doenças crônicas) e Grupo II (62 pacientes portadores de hepatopatias, pneumopatias, nefropatias, neoplasias, úlceras, gastrites, e doenças hematológicas), denominados PTodos. Em cada paciente, foram obtidas as seguintes medidas ant...
Frajtova-Michalikova, Katarina; Spuchľakova, Erika; Misankova, Maria
2015-01-01
In this paper Portfolio Optimization techniques were used to determine the most favorable investment portfolio. In particular, stock indices of three companies, namely Microsoft Corporation, Christian Dior Fashion House and Shevron Corporation were evaluated. Using this data the amounts invested in each asset when a portfolio is chosen on the efficient frontier were calculated. In addition, the Portfolio with minimum variance, tangency portfolio and optimal Markowitz portfolio are presented.
Institute of Scientific and Technical Information of China (English)
李扬璐; 阮祥燕; 崔亚美; 赵越; 武红琴; 杜鹃; Alfred O. Mueck
2015-01-01
Objective To investigate and compare predictive diagnostic value of the low density lipoprotein-cholesterol( LDL-C)/high density lipoprotein-cholesterol( HDL-C) , apolipoprotein( Apo) B/ApoAI, triglyceride( TG)/HDL-C, total cholesterol( TC)/HDL-C ratios for metabolic syndrome(MS) in patients with polycystic ovary syndrome(PCOS). Methods A total of 441 patients with PCOS were included in this study, whose height, weight, waist circumference were measured. Fasting venous blood specimens were collected on their first to fifth day of menstrual cycle to measure their concentration of sex hormones and metabolic parameters. All patients were devided into two groups according to the international diabetes federation( IDF) diagnostic criteria:MS group and non-MS group. Differences between the two groups were compared, including age, blood pressure, BMI, waist circumference, waist-to hip circumference ratio, fasting glucose, fasting insulin, LDL-C, HDL-C, Lp( a) , triglyceride, total cholesterol etc. Correlations between the 4 ratios and parameters in MS diagnostic criteria mentioned above were analyzed respectively. The whole patients were divided into 6 groups by the number of abnormal component, from 0 component to 5 components. The mean values of 4 ratios were compared between 6 groups. The diagnostic value of 4 ratios were determined and compared by ROC curves. Results Mean values of the 4 serum lipoprotein ratio were increased as increase in the number of abnormal components, and all of the ratios were significantly correlated with parameters in MS criteria. TG/HDL-C obtained the highest area under the curve(AUC) of 0. 941 determined by ROC curves, suggesting that TG/HDL-C has the greatest diagnostic value of MS. The cutoff value of TG/HDL-C was set at 1. 089, with the sensitivity of 0. 864 and the specificity of 0. 891. Conclusion TG/HDL-C has the best diagnostic value for MS among 4 ratios. Patients with PCOS whose TG/HDL-C ratio is over 1. 089 should be informed
Energy Technology Data Exchange (ETDEWEB)
Birzvalk, Yu.
1978-01-01
The shunting ratio and the local shunting ratio, pertaining to currents induced by a magnetic field in a flow channel, are properly defined and systematically reviewed on the basis of the Lagrange criterion. Their definition is based on the energy balance and related to dimensionless parameters characterizing an MHD flow, these parameters evolving from the Hartmann number and the hydrodynamic Reynolds number as well as the magnetic Reynolds number, and the Lundquist number. These shunting ratios, of current density in the core of a stream (uniform) or equivalent mean current density to the short-circuit (maximum) current density, are given here for a slot channel with nonconducting or conducting walls, for a conduction channel with heavy side rails, and for an MHD-flow around bodies. 5 references, 1 figure.
Finding the Minimum Ratio Traveling Salesman Tour by Artificial Ants
Institute of Scientific and Technical Information of China (English)
马良; 崔雪丽; 姚俭
2003-01-01
Ants of artificial colony are able to generate good solutions to the famous traveling salesman problem (TSP).We propose an artificial ants algorithm for solving the minimum ratio TSP, which is more general than the standard TSP in combinatorial optimization area. In the minimum ratio TSP, another criterion concerning each edge is added, that is,the traveling salesman can have a benefit if he travels from one city to another. The objective is to minimize the ratio between total costs or distances and total benefits. The idea of this type of optimization is in some sense quite similar to that of traditional cost-benefit analysis in management science. Computational results substantiate the solution quality and efficiency of the algorithm.
Incentive Ratios of Fisher Markets
DEFF Research Database (Denmark)
Chen, Ning; Deng, Xuaitue; Zhang, Hongyang
2012-01-01
In a Fisher market, a market maker sells m items to n potential buyers. The buyers submit their utility functions and money endowments to the market maker, who, upon receiving submitted information, derives market equilibrium prices and allocations of its items. While agents may benefit...... by misreporting their private information, we show that the percentage of improvement by a unilateral strategic play, called incentive ratio, is rather limited—it is less than 2 for linear markets and at most $e^{1/e}\\thickapprox 1.445$ for Cobb-Douglas markets. We further prove that both ratios are tight....
Ratio Bias and Policy Preferences
DEFF Research Database (Denmark)
Pedersen, Rasmus Tue
2016-01-01
Numbers permeate modern political communication. While current scholarship on framing effects has focused on the persuasive effects of words and arguments, this article shows that framing of numbers can also substantially affect policy preferences. Such effects are caused by ratio bias, which...... is a general tendency to focus on numerators and pay insufficient attention to denominators in ratios. Using a population-based survey experiment, I demonstrate how differently framed but logically equivalent representations of the exact same numerical value can have large effects on citizens’ preferences...
Ratio Bias and Policy Preferences
DEFF Research Database (Denmark)
Pedersen, Rasmus Tue
2016-01-01
Numbers permeate modern political communication. While current scholarship on framing effects has focused on the persuasive effects of words and arguments, this article shows that framing of numbers can also substantially affect policy preferences. Such effects are caused by ratio bias, which is ...
Gender Ratios for Reading Difficulties
Hawke, Jesse L.; Olson, Richard K.; Willcut, Erik G.; Wadsworth, Sally J.; DeFries, John C.
2009-01-01
The prevalence of reading difficulties is typically higher in males than females in both referred and research-identified samples, and the ratio of males to females is greater in more affected samples. To explore possible gender differences in reading performance, we analysed data from 1133 twin pairs in which at least one member of each pair had…
Risk modelling in portfolio optimization
Lam, W. H.; Jaaman, Saiful Hafizah Hj.; Isa, Zaidi
2013-09-01
Risk management is very important in portfolio optimization. The mean-variance model has been used in portfolio optimization to minimize the investment risk. The objective of the mean-variance model is to minimize the portfolio risk and achieve the target rate of return. Variance is used as risk measure in the mean-variance model. The purpose of this study is to compare the portfolio composition as well as performance between the optimal portfolio of mean-variance model and equally weighted portfolio. Equally weighted portfolio means the proportions that are invested in each asset are equal. The results show that the portfolio composition of the mean-variance optimal portfolio and equally weighted portfolio are different. Besides that, the mean-variance optimal portfolio gives better performance because it gives higher performance ratio than the equally weighted portfolio.
DEFF Research Database (Denmark)
Frandsen, P. E.; Jonasson, K.; Nielsen, Hans Bruun
1999-01-01
This lecture note is intended for use in the course 04212 Optimization and Data Fitting at the Technincal University of Denmark. It covers about 25% of the curriculum. Hopefully, the note may be useful also to interested persons not participating in that course. The aim of the note is to give...... an introduction to algorithms for unconstrained optimization. We present Conjugate Gradient, Damped Newton and Quasi Newton methods together with the relevant theoretical background. The reader is assumed to be familiar with algorithms for solving linear and nonlinear system of equations, at a level corresponding...
DEFF Research Database (Denmark)
Frandsen, P. E.; Jonasson, K.; Nielsen, Hans Bruun
1999-01-01
This lecture note is intended for use in the course 04212 Optimization and Data Fitting at the Technincal University of Denmark. It covers about 25% of the curriculum. Hopefully, the note may be useful also to interested persons not participating in that course. The aim of the note is to give...... an introduction to algorithms for unconstrained optimization. We present Conjugate Gradient, Damped Newton and Quasi Newton methods together with the relevant theoretical background. The reader is assumed to be familiar with algorithms for solving linear and nonlinear system of equations, at a level corresponding...
New genetic loci link adipose and insulin biology to body fat distribution
DEFF Research Database (Denmark)
Shungin, Dmitry; Winkler, Thomas W; Croteau-Chonka, Damien C.
2015-01-01
(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated......Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome...... adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms....
DEFF Research Database (Denmark)
Andreassen, Ole A; Djurovic, Srdjan; Thompson, Wesley K;
2013-01-01
-pleiotropy-informed method for improving gene discovery with the use of GWAS summary-statistics data. We applied this methodology to identify additional loci associated with schizophrenia (SCZ), a highly heritable disorder with significant missing heritability. Epidemiological and clinical studies suggest comorbidity...... between SCZ and cardiovascular-disease (CVD) risk factors, including systolic blood pressure, triglycerides, low- and high-density lipoprotein, body mass index, waist-to-hip ratio, and type 2 diabetes. Using stratified quantile-quantile plots, we show enrichment of SNPs associated with SCZ as a function...
DEFF Research Database (Denmark)
Jørgensen, Marit Eika; Moustgaard, Helene; Bjerregaard, Peter
2006-01-01
BACKGROUND: The Inuit have gone through an accelerated process of modernization especially since 1950. Primarily because of the dietary transition, westernisation is expected to influence the Inuit's metabolic risk in a negative way with respect to cardiovascular risk. The aim was to analyze...... metabolic risk factors among Inuit in Greenland and Denmark and their relation to westernization. METHODS: 1173 adult Inuit participated in a health survey in Greenland and Denmark. The examination included a 75 g OGTT. BMI, waist-to-hip ratio, and blood pressure were measured. P-glucose, s-insulin, lipids...
Folate and Breast Cancer: Role of Intake, Blood Levels, and Metabolic Gene Polymorphisms
2006-06-01
and dietary factors are presented in Table 1. Cases were, in general, more highly educated, more likely to have a history of fibroadenoma , younger...12.0 10.1 0.05 Breast cancer in first-degree relative, % 3.4 2.4 0.15 Ever had breast fibroadenoma , % 9.7 5.2 0.01 Age at menarche (yr) 14.5 1.6...15/13 1.4 (0.6-3.0) *All ORs are adjusted for age, history of fibroadenoma , waist-to-hip ratio, age at first live birth, physical activity, and total
DEFF Research Database (Denmark)
Bugge, Anna; Hermansen, Bianca El-Naaman; Froberg, Karsten
13.35 yr in 7th grade). BMI, sum of 4 skinfolds (S4SF) and waist to hip ratio (WHR) were measured. PA was measured using CSA accelerometers for four consecutive days. Aerobic fitness (VO2max) was directly measured during a maximal progressive running test on a treadmill. Fasting intravenous blood...... to CG-boys. There were no differences between groups in VO2max or PA at any time point. Our results suggest that school-based intervention might have an effect on CVD risk factors even without measurable changes in fitness and fatness. Funded by The Danish Heart Foundation and The Denmark...
Eckmann, B
2008-01-01
At the close of the 1980s, the independent contributions of Yann Brenier, Mike Cullen and John Mather launched a revolution in the venerable field of optimal transport founded by G Monge in the 18th century, which has made breathtaking forays into various other domains of mathematics ever since. The author presents a broad overview of this area.
DEFF Research Database (Denmark)
Bendsøe, Martin P.; Sigmund, Ole
2007-01-01
Taking as a starting point a design case for a compliant mechanism (a force inverter), the fundamental elements of topology optimization are described. The basis for the developments is a FEM format for this design problem and emphasis is given to the parameterization of design as a raster image...
DYNAMIC TEACHING RATIO PEDAGOGIC MODEL
Directory of Open Access Journals (Sweden)
Chen Jiaying
2010-11-01
Full Text Available This paper outlines an innovative pedagogic model, Dynamic Teaching Ratio (DTR Pedagogic Model, for learning design and teaching strategy aimed at the postsecondary technical education. The model draws on the theory of differential learning, which is widely recognized as an important tool for engaging students and addressing the individual needs of all students. The DTR model caters to the different abilities, interest or learning needs of students and provides different learning approaches based on a student’s learning ability. The model aims to improve students’ academic performance through increasing the lecturer-to-student ratio in the classroom setting. An experimental case study on the model was conducted and the outcome was favourable. Hence, a large-scale implementation was carried out upon the successful trial run. The paper discusses the methodology of the model and its application through the case study and the large-scale implementation.
Lipoprotein ratios: Physiological significance and clinical usefulness in cardiovascular prevention.
Millán, Jesús; Pintó, Xavier; Muñoz, Anna; Zúñiga, Manuel; Rubiés-Prat, Joan; Pallardo, Luis Felipe; Masana, Luis; Mangas, Alipio; Hernández-Mijares, Antonio; González-Santos, Pedro; Ascaso, Juan F; Pedro-Botet, Juan
2009-01-01
Low-density lipoprotein (LDL) cholesterol concentration has been the prime index of cardiovascular disease risk and the main target for therapy. However, several lipoprotein ratios or "atherogenic indices" have been defined in an attempt to optimize the predictive capacity of the lipid profile. In this review, we summarize their pathophysiological aspects, and highlight the rationale for using these lipoprotein ratios as cardiovascular risk factors in clinical practice, specifying their cut-off risk levels and a target for lipid-lowering therapy. Total/high-density lipoprotein (HDL) cholesterol and LDL/HDL cholesterol ratios are risk indicators with greater predictive value than isolated parameters used independently, particularly LDL. Future recommendations regarding the diagnosis and treatment of dyslipidemia, including instruments for calculating cardiovascular risk or action guidelines, should include the lipoprotein ratios with greater predictive power which, in view of the evidence-based results, are none other than those which include HDL cholesterol.
Envera Variable Compression Ratio Engine
Energy Technology Data Exchange (ETDEWEB)
Charles Mendler
2011-03-15
Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy has already demonstrated a degree of success, downsizing and fuel economy gains are currently limited. With new variable compression ratio technology however, the degree of engine downsizing and fuel economy improvement can be greatly increased. A small variable compression ratio (VCR) engine has the potential to return significantly higher vehicle fuel economy while also providing high power. Affordability and potential for near term commercialization are key attributes of the Envera VCR engine. VCR Technology To meet torque and power requirements, a smaller engine needs to do more work per stroke. This is typically accomplished by boosting the incoming charge with either a turbo or supercharger so that more energy is present in the cylinder per stroke to do the work. With current production engines the degree of engine boosting (which correlates to downsizing) is limited by detonation (combustion knock) at high boost levels. Additionally, the turbo or supercharger needs to be responsive and efficient while providing the needed boost. VCR technology eliminates the limitation of engine knock at high load levels by reducing compression ratio to {approx}9:1 (or whatever level is appropriate) when high boost pressures are needed. By reducing the compression ratio during high load demand periods there is increased volume in the cylinder at top dead center (TDC) which allows more charge (or energy) to be present in the cylinder without increasing the peak pressure. Cylinder pressure is thus kept below the level at which the engine would begin to knock. When loads on the engine are low
Noise of Embedded High Aspect Ratio Nozzles
Bridges, James E.
2011-01-01
A family of high aspect ratio nozzles were designed to provide a parametric database of canonical embedded propulsion concepts. Nozzle throat geometries with aspect ratios of 2:1, 4:1, and 8:1 were chosen, all with convergent nozzle areas. The transition from the typical round duct to the rectangular nozzle was designed very carefully to produce a flow at the nozzle exit that was uniform and free from swirl. Once the basic rectangular nozzles were designed, external features common to embedded propulsion systems were added: extended lower lip (a.k.a. bevel, aft deck), differing sidewalls, and chevrons. For the latter detailed Reynolds-averaged Navier-Stokes (RANS) computational fluid dynamics (CFD) simulations were made to predict the thrust performance and to optimize parameters such as bevel length, and chevron penetration and azimuthal curvature. Seventeen of these nozzles were fabricated at a scale providing a 2.13 inch diameter equivalent area throat." ! The seventeen nozzles were tested for far-field noise and a few data were presented here on the effect of aspect ratio, bevel length, and chevron count and penetration. The sound field of the 2:1 aspect ratio rectangular jet was very nearly axisymmetric, but the 4:1 and 8:1 were not, the noise on their minor axes being louder than the major axes. Adding bevel length increased the noise of these nozzles, especially on their minor axes, both toward the long and short sides of the beveled nozzle. Chevrons were only added to the 2:1 rectangular jet. Adding 4 chevrons per wide side produced some decrease at aft angles, but increased the high frequency noise at right angles to the jet flow. This trend increased with increasing chevron penetration. Doubling the number of chevrons while maintaining their penetration decreased these effects. Empirical models of the parametric effect of these nozzles were constructed and quantify the trends stated above." Because it is the objective of the Supersonics Project that
Klesh, Andrew T.
This dissertation studies optimal exploration, defined as the collection of information about given objects of interest by a mobile agent (the explorer) using imperfect sensors. The key aspects of exploration are kinematics (which determine how the explorer moves in response to steering commands), energetics (which determine how much energy is consumed by motion and maneuvers), informatics (which determine the rate at which information is collected) and estimation (which determines the states of the objects). These aspects are coupled by the steering decisions of the explorer. We seek to improve exploration by finding trade-offs amongst these couplings and the components of exploration: the Mission, the Path and the Agent. A comprehensive model of exploration is presented that, on one hand, accounts for these couplings and on the other hand is simple enough to allow analysis. This model is utilized to pose and solve several exploration problems where an objective function is to be minimized. Specific functions to be considered are the mission duration and the total energy. These exploration problems are formulated as optimal control problems and necessary conditions for optimality are obtained in the form of two-point boundary value problems. An analysis of these problems reveals characteristics of optimal exploration paths. Several regimes are identified for the optimal paths including the Watchtower, Solar and Drag regime, and several non-dimensional parameters are derived that determine the appropriate regime of travel. The so-called Power Ratio is shown to predict the qualitative features of the optimal paths, provide a metric to evaluate an aircrafts design and determine an aircrafts capability for flying perpetually. Optimal exploration system drivers are identified that provide perspective as to the importance of these various regimes of flight. A bank-to-turn solar-powered aircraft flying at constant altitude on Mars is used as a specific platform for
Aschepkov, Leonid T; Kim, Taekyun; Agarwal, Ravi P
2016-01-01
This book is based on lectures from a one-year course at the Far Eastern Federal University (Vladivostok, Russia) as well as on workshops on optimal control offered to students at various mathematical departments at the university level. The main themes of the theory of linear and nonlinear systems are considered, including the basic problem of establishing the necessary and sufficient conditions of optimal processes. In the first part of the course, the theory of linear control systems is constructed on the basis of the separation theorem and the concept of a reachability set. The authors prove the closure of a reachability set in the class of piecewise continuous controls, and the problems of controllability, observability, identification, performance and terminal control are also considered. The second part of the course is devoted to nonlinear control systems. Using the method of variations and the Lagrange multipliers rule of nonlinear problems, the authors prove the Pontryagin maximum principle for prob...
Trommer, Jochen
2005-01-01
In dieser Dissertation schlage ich eine Synthese (Distributed Optimality, DO) von Optimalitätstheorie und einem derivationellen, morphologischem Asatz, Distributed Morphology (DM; Halle & Marantz, 1993) vor. Durch die Integration von OT in DM wird es möglich, Phänomene, die in DM durch sprachspezifische Regeln oder Merkmale von lexikalischen Einträge erfasst werden, auf die Interaktion von verletzbaren, universellen Constraints zurückzuführen. Andererseits leistet auch DM zwei substantielle B...
Powell, Warren B
2012-01-01
Learn the science of collecting information to make effective decisions Everyday decisions are made without the benefit of accurate information. Optimal Learning develops the needed principles for gathering information to make decisions, especially when collecting information is time-consuming and expensive. Designed for readers with an elementary background in probability and statistics, the book presents effective and practical policies illustrated in a wide range of applications, from energy, homeland security, and transportation to engineering, health, and business. This book covers the
Directory of Open Access Journals (Sweden)
Yaping Hu
2015-01-01
the nonsmooth convex optimization problem. First, by using Moreau-Yosida regularization, we convert the original objective function to a continuously differentiable function; then we use approximate function and gradient values of the Moreau-Yosida regularization to substitute the corresponding exact values in the algorithm. The global convergence is proved under suitable assumptions. Numerical experiments are presented to show the effectiveness of this algorithm.
Hoppe, Fred M; Hoppe, Daniel J; Walter, Stephen D
2017-02-01
The aim of this analysis was to provide an alternative derivation of the odds ratio (OR) to provide an intuitive meaning, freeing it from any mention of odds, which may make it a more useful concept for clinicians to use when describing treatment effect. By examining the four possible combinations of treatment/control and corresponding outcomes, we considered the conditional risk ratio (RR, also known as relative risk) of an event with the treatment compared with an event with the control for pairs of patients for whom treatment and control would yield different results. Both matched and unmatched studies are considered. We found that the OR could be derived as the RR of an outcome with treatment compared with an outcome with control conditional on the treatment and control resulting in different outcomes, thus providing a measure of the net benefit of treatment. It has been claimed that the OR comparing the effect of treatment vs. control does not have the same clinical interpretability as RR because it involves ratios of odds and so is difficult to explain in terms of patient numbers. This new derivation provides an interpretation of the OR as an RR but conditional on treatment and control resulting in different outcomes. This may help explain the reason ORs cause interpretation difficulties in practice. Moreover, the OR may be a more clinically useful parameter to patients because it deals with only those situations where the outcome differs between the two groups. Copyright © 2016 Elsevier Inc. All rights reserved.
Gender ratios for reading difficulties
Hawke, Jesse L.; Olson, Richard K.; Willcutt, Erik G.; Wadsworth, Sally J.; DeFries, John C.
2009-01-01
The prevalence of reading difficulties is typically higher in males than females in both referred and research-identified samples, and the ratio of males to females is greater in more affected samples. To explore possible gender differences in reading performance, we analyzed data from 1,133 twin pairs in which at least one member of each pair had a school-history of reading problems and from 684 twin pairs from a comparison sample with no reading difficulties. Although the difference between...
Directory of Open Access Journals (Sweden)
Vestbo J
2012-09-01
Full Text Available Jørgen VestboUniversity of Manchester, Manchester, UKI read with interest the paper entitled "Diagnosis of airway obstruction in the elderly: contribution of the SARA study" by Sorino et al in a recent issue of this journal.1 Being involved in the Global Initiative for Obstructive Lung Diseases (GOLD, it is nice to see the interest sparked by the GOLD strategy document. However, in the paper by Sorino et al, there are a few misunderstandings around GOLD and the fixed ratio (forced expiratory volume in 1 second/forced volume vital capacity < 0.70 that need clarification.View original paper by Sorino and colleagues.
Switched reluctance motor optimal geometry design
Directory of Open Access Journals (Sweden)
Liviu Neamt
2010-12-01
Full Text Available This paper deals with the Switched Reluctance Motor (SRM analysis using Finite Element Method (FEM for geometrical optimization in terms of volume ratio of torque on the rotor, the so-called specific torque. The optimization parameter is the pair: stator and rotor pole angles, which forms a crucial part of the design process.
Optimal Hedging with the Vector Autoregressive Model
L. Gatarek (Lukasz); S.G. Johansen (Soren)
2014-01-01
markdownabstract__Abstract__ We derive the optimal hedging ratios for a portfolio of assets driven by a Cointegrated Vector Autoregressive model with general cointegration rank. Our hedge is optimal in the sense of minimum variance portfolio. We consider a model that allows for the hedges to be
Transformer ratio saturation in a beam-driven wakefield accelerator
Energy Technology Data Exchange (ETDEWEB)
Farmer, J. P.; Martorelli, R.; Pukhov, A. [Institut für Theoretische Physik I, Heinrich Heine Universität, 40225 Düsseldorf (Germany)
2015-12-15
We show that for beam-driven wakefield acceleration, the linearly ramped, equally spaced train of bunches typically considered to optimise the transformer ratio only works for flat-top bunches. Through theory and simulation, we explain that this behaviour is due to the unique properties of the plasma response to a flat-top density profile. Calculations of the optimal scaling for a train of Gaussian bunches show diminishing returns with increasing bunch number, tending towards saturation. For a periodic bunch train, a transformer ratio of 23 was achieved for 50 bunches, rising to 40 for a fully optimised beam.
Variational transport coefficients for low aspect ratio, low collisionality stellarators
Hirshman, S. P.; Spong, D. A.; D'Azevedo, E.; Peyton, B.; Lawkins, W.
2001-10-01
Stellarators with low aspect ratios (A converged results for these bounds. The convergence of DKES as the number of basis functions is varied is examined for several low aspect ratio configurations corresponding to the proposed NCSX and QPS experiments. It is shown that even on fairly coarse meshes, the minimax extremum yields a good approximation to the final (very fine mesh) values of the transport coefficients. Methods for optimally selecting the basis harmonic components, and hence greatly reducing the computational effort, are described. Iterative solution techniques have been developed which are scaleable to higher dimensional problems that include radial drift orbit effects. These methods are compared with the presently used Thomas algorithm.
Montenegro-Johnson, Thomas D; Lauga, Eric
2014-06-01
Propulsion at microscopic scales is often achieved through propagating traveling waves along hairlike organelles called flagella. Taylor's two-dimensional swimming sheet model is frequently used to provide insight into problems of flagellar propulsion. We derive numerically the large-amplitude wave form of the two-dimensional swimming sheet that yields optimum hydrodynamic efficiency: the ratio of the squared swimming speed to the rate-of-working of the sheet against the fluid. Using the boundary element method, we show that the optimal wave form is a front-back symmetric regularized cusp that is 25% more efficient than the optimal sine wave. This optimal two-dimensional shape is smooth, qualitatively different from the kinked form of Lighthill's optimal three-dimensional flagellum, not predicted by small-amplitude theory, and different from the smooth circular-arc-like shape of active elastic filaments.
Design of passive vehicle suspensions for maximal least damping ratio
Smith, Malcolm C.; Swift, Stuart J.
2016-05-01
This paper studies the use of the least damping ratio among system poles as a performance metric in passive vehicle suspensions. Methods are developed which allow optimal solutions to be computed in terms of non-dimensional quantities in a quarter-car vehicle model. Solutions are provided in graphical form for convenient use across vehicle types. Three suspension arrangements are studied: the standard suspension involving a parallel spring and damper and two further suspension arrangements involving an inerter. The key parameters for the optimal solutions are the ratios of unsprung mass to sprung mass and suspension static stiffness to tyre vertical stiffness. A discussion is provided of performance trends in terms of the key parameters. A comparison is made with the optimisation of ride comfort and tyre grip metrics for various vehicle types.
Parker, R Gary
1988-01-01
This book treats the fundamental issues and algorithmic strategies emerging as the core of the discipline of discrete optimization in a comprehensive and rigorous fashion. Following an introductory chapter on computational complexity, the basic algorithmic results for the two major models of polynomial algorithms are introduced--models using matroids and linear programming. Further chapters treat the major non-polynomial algorithms: branch-and-bound and cutting planes. The text concludes with a chapter on heuristic algorithms.Several appendixes are included which review the fundamental ideas o
Chvátal, V
2011-01-01
This book is a collection of six articles arising from the meeting of the NATO Advanced Study Institute (ASI) "Combinatorial Optimization: Methods and Applications," which was held at the University of Montreal in June 2006. This ASI consisted of seven series of five one-hour lectures and one series of four one-hour lectures. It was attended by some sixty students of graduate or postdoctoral level from fifteen countries worldwide. It includes topics such as: integer and mixed integer programming, facility location, branching on split disjunctions, convexity in combinatorial optimizat
Camps, Xavier; Velasco Quesada, Guillermo; Hoz Casas, Jordi de la; Martín Cañadas, María Elena
2015-01-01
This work presents a novel approach to the experimental validation of the optimal PV-to-inverter sizing ratio value for the energy yield maximization of a GCPVS by means the implementation of a custom workbench using a solar array simulator which has allowed to replicate a wide variety of technical configurations and environmental data. The compliance between the experimental setup and the mathematical model developed to simulate the optimal PV-to-inverter sizing ratio value was demonstrated ...
High-performance metasurface polarizers with extinction ratios exceeding 12000.
Kurosawa, Hiroyuki; Choi, Bongseok; Sugimoto, Yoshimasa; Iwanaga, Masanobu
2017-02-20
High-performance ultrathin polarizers have been experimentally demonstrated employing stacked complementary (SC) metasurfaces, which were produced using nanoimprint lithography. It is experimentally determined that the metasurface polarizers composed of Ag and Au have large extinction ratios exceeding 17000 and 12000, respectively, in spite of the subwavelength thickness. It is also shown that the ultrathin polarizers of the SC structures are optimized at telecommunication wavelengths.
Weather-Corrected Performance Ratio
Energy Technology Data Exchange (ETDEWEB)
Dierauf, T.; Growitz, A.; Kurtz, S.; Cruz, J. L. B.; Riley, E.; Hansen, C.
2013-04-01
Photovoltaic (PV) system performance depends on both the quality of the system and the weather. One simple way to communicate the system performance is to use the performance ratio (PR): the ratio of the electricity generated to the electricity that would have been generated if the plant consistently converted sunlight to electricity at the level expected from the DC nameplate rating. The annual system yield for flat-plate PV systems is estimated by the product of the annual insolation in the plane of the array, the nameplate rating of the system, and the PR, which provides an attractive way to estimate expected annual system yield. Unfortunately, the PR is, again, a function of both the PV system efficiency and the weather. If the PR is measured during the winter or during the summer, substantially different values may be obtained, making this metric insufficient to use as the basis for a performance guarantee when precise confidence intervals are required. This technical report defines a way to modify the PR calculation to neutralize biases that may be introduced by variations in the weather, while still reporting a PR that reflects the annual PR at that site given the project design and the project weather file. This resulting weather-corrected PR gives more consistent results throughout the year, enabling its use as a metric for performance guarantees while still retaining the familiarity this metric brings to the industry and the value of its use in predicting actual annual system yield. A testing protocol is also presented to illustrate the use of this new metric with the intent of providing a reference starting point for contractual content.
Optimal parameters uncoupling vibration modes of oscillators
Le, K. C.; Pieper, A.
2017-07-01
This paper proposes a novel optimization concept for an oscillator with two degrees of freedom. By using specially defined motion ratios, we control the action of springs to each degree of freedom of the oscillator. We aim at showing that, if the potential action of the springs in one period of vibration, used as the payoff function for the conservative oscillator, is maximized among all admissible parameters and motions satisfying Lagrange's equations, then the optimal motion ratios uncouple vibration modes. A similar result holds true for the dissipative oscillator having dampers. The application to optimal design of vehicle suspension is discussed.
Optimal parameters uncoupling vibration modes of oscillators
Le, Khanh Chau
2016-01-01
A novel optimization concept for an oscillator with two degrees of freedom is proposed. By using specially defined motion ratios, we control the action of springs and dampers to each degree of freedom of the oscillator. If the potential action of the springs in one period of vibration, used as the payoff function for the conservative oscillator, is maximized, then the optimal motion ratios uncouple vibration modes. The same result holds true for the dissipative oscillator. The application to optimal design of vehicle suspension is discussed.
Aircraft Trajectory Optimization Using Parametric Optimization Theory
Valenzuela Romero, Alfonso
2012-01-01
In this thesis, a study of the optimization of aircraft trajectories using parametric optimization theory is presented. To that end, an approach based on the use of predefined trajectory patterns and parametric optimization is proposed. The trajectory pat
Optimal performance of regenerative cryocoolers
de Boer, P. C. T.
2011-02-01
The key component of a regenerative cryocooler is its regenerative heat exchanger. This device is subject to losses due to imperfect heat transfer between the regenerator material and the gas, as well as due to viscous dissipation. The relative magnitudes of these losses can be characterized by the ratio of the Stanton number St to the Fanning friction factor f. Using available data for the ratio St/ f, results are developed for the optimal cooling rate and Carnot efficiency. The variations of pressure and temperature are taken to be sinusoidal in time, and to have small amplitudes. The results are applied to the case of the Stirling cryocooler, with flow being generated by pistons at both sides of the regenerator. The performance is found to be close to optimal at large ratio of the warm space volume to the regenerator void volume. The results are also applied to the Orifice Pulse Tube Refrigerator. In this case, optimal performance additionally requires a large ratio of the regenerator void volume to the cold space volume.
Hu, Q; Jiang, C Q; Zhang, W S; Cheng, J J; Xu, L; Jin, Y L; Rao, S L; Zheng, H Q; Lam, D Q
2016-10-10
Objective: To examine the correlation between body fat percentage (BFP) and general obesity indexes, including body mass index (BMI), waist circumference (WC) and waist to hip ratio (WHR) and calculate the corresponding BFP cutoff values in the middle aged and old people in Guangzhou. The corresponding cut-point of optimal body fat percentage for Guangzhou older population. Methods: Based on the Guangzhou Biobank Cohort Study (GBCS), 3 490 relatively healthy Guangzhou residents aged ≥50 years were selected and were randomly divided into 2 groups. The equations between BFP and BMI, WC, WHR were set up with Curve fitting analysis in one group. The multiple regression analysis was undertaken to establish predictive equations between BFP and BMI, WC, WHR with stepwise model for adding gender, age, physical activity, drinking and smoking. Then, the optimal cut-points of BFP corresponding to BMI, WC and WHR to reflect the degree of obesity were calculated. The equations were then validated with another group. Results: BFP increased with the increase of WHR, WC and BMI. BMI was a better predictor of body fat percentage than WC and WHR. The final regression equation was BFP=(-23.47 -8.87×sex) +2.94× (BMI) - 0.024 × (BMI)(2),the coefficient of determination was 0.805. Based on the equation, the BFP corresponding to overweight/obesity (24 kg/m(2)≤BMIobesity compared with WC and WHR, obtained the area of ROC 0.909 in men and 0.919 in women respectively. The sensitivity and specificity were 70.3% and 85.5% in men; and 75.2% and 93.0% in women respectively. Conclusion: BFP has a better correlation with BMI. The study results indicated that BFP for middle aged and old males and females in Guangzhou corresponding to overweight/obesity (BMI≥24 kg/m(2)) were <24.0% and <33.0% respectively.
On Optimizing the Satisfiability (SAT) Problem
Institute of Scientific and Technical Information of China (English)
GU Jun; GU Qianping; DU Dingzhu
1999-01-01
The satisfiability(SAT) problem is abasic problem in computing theory. Presently, an active area of researchon SAT problem is to design efficient optimization algorithms forfinding a solution for a satisfiable CNF formula. A newformulation, the Universal SAT problem model, which transforms the SAT problem on Boolean space into an optimization problem on real spacehas been developed. Many optimization techniques,such as the steepest descent method, Newton's method, and thecoordinate descent method, can be used to solve the Universal SAT problem. In this paper, we prove that, when the initial solution issufficiently close to the optimal solution, the steepest descent methodhas a linear convergence ratio β<1, Newton's method has aconvergence ratio of order two, and the convergence ratio of thecoordinate descent method is approximately (1-β/m) for the Universal SAT problem with m variables. An algorithm based on the coordinate descent method for the Universal SAT problem is alsopresented in this paper.
Bionomic Exploitation of a Ratio-Dependent Predator-Prey System
Maiti, Alakes; Patra, Bibek; Samanta, G. P.
2008-01-01
The present article deals with the problem of combined harvesting of a Michaelis-Menten-type ratio-dependent predator-prey system. The problem of determining the optimal harvest policy is solved by invoking Pontryagin's Maximum Principle. Dynamic optimization of the harvest policy is studied by taking the combined harvest effort as a dynamic…
Ravensbergen, Henrike Rianne Joanna Cornelie; Lear, Scott Alexander; Claydon, Victoria Elizabeth
2014-02-01
Obesity is an important identifier of cardiovascular disease (CVD) risk, but is challenging to determine accurately in individuals with spinal cord injury (SCI). Body mass index (BMI) is used worldwide as a simple indicator of obesity, but is difficult to measure in individuals with SCI. Furthermore, standard BMI cutoffs underestimate obesity in this population. Therefore, we aimed to identify the best marker of obesity in individuals with SCI, considering both practicality, and ability to detect adiposity and CVD risk. Five anthropometric measures were evaluated: BMI; waist circumference (WC); waist-to-height ratio (WHtR); waist-to-hip ratio; and neck circumference. We evaluated relationships between these measures and abdominal and total body-fat percentage, seven cardiovascular metabolic risk factors (fasting insulin, glucose, glucose tolerance, triglycerides, high-density lipoprotein, low-density lipoprotein, and total cholesterol), and the Framingham risk score. BMI, WC, and WHtR were correlated with abdominal fat percentage. WC and WHtR were correlated with five metabolic risk factors as well as the Framingham risk score. WC is a more practical measure for an SCI population. The optimal cutoff for identifying adverse CVD risk in individuals with SCI was identified as WC ≥94 cm, with 100% sensitivity and 79% specificity. We propose that WC is a simple, more sensitive alternative to BMI in this population that is easy to use in multiple settings. The cutoff provides a simple tool to predict adverse CVD risk profiles that can be used to guide risk management, as well as as a practical aid for individuals with SCI to maintain a healthy body composition.
Caste ratios affect the reproductive output of social trematode colonies.
Kamiya, T; Poulin, R
2013-03-01
Intraspecific phenotypic diversification in social organisms often leads to formation of physical castes which are morphologically specialized for particular tasks within the colony. The optimal caste allocation theory argues that specialized morphological castes are efficient at specific tasks, and hence different caste ratios should affect the ergonomic efficiency, hence reproductive output of the colony. However, the reproductive output of different caste ratios has been documented in few species of insects with equivocal support for the theory. This study investigated whether the ratios of nonreproductive and reproductive morphs affect the reproductive output of a recently discovered social trematode, Philophthalmus sp., in which the nonreproductive members are hypothesized to be defensive specialists. A census of natural infections and a manipulative in vitro experiment demonstrated a positive association between the reproductive output of trematode colonies and the ratio of nonreproductive to reproductive morphs in the presence of an intra-host trematode competitor, Maritrema novaezealandensis. On the contrary, without the competitor, reproductive output was negatively associated with the proportion of nonreproductive castes in colonies. Our findings demonstrate for the first time a clear fitness benefit associated with the nonreproductive castes in the presence of a competitor while illustrating the cost of maintaining such morphs in noncompetitive situations. Although the proximate mechanisms controlling caste ratio remain unclear in this trematode system, this study supports the prediction that the fitness of colonies is influenced by the composition of specialized functional morphs in social organisms, suggesting a potential for adaptive shifts of caste ratios over evolutionary time.
Directory of Open Access Journals (Sweden)
Öje Danell
1999-04-01
Full Text Available Optimal Production in Reindeer Husbandry.There are three ways to optimize the reindeer herd: 1 Adjusting the reindeer number to pasture resources. 2 Keeping as many productive animals in the herd as possible through slaughter. 3 Increasing the herd quality through selection.Renhjorden bör optimeras så att den fungerar som en "skördeapparat" for bete och lämnar största möjliga bidrag till försörjningen för dem som lever av renskötsel. Det finns minst tre sätt att optimera renhjorden, nämligen (1 anpassning av djurantalet till betesresurserna så att djurens kondition och därmed produktiviteten kan bibehållas på hög nivå, (2 utforma renhjordens struktur med hjalp av slaktuttaget så att den innehåller så stor andel produktiva djur som möjligt, och (3 förbättra djurmaterialets produktionsmässiga kvalitet genom urval baserat på registrerad produktion. Betesanpassningen är den mest grundläggande åtgärden och ger den snabbaste effekten. Även hjordstrukturering är en åtgärd som ger relativt snabb effekt och som dessutom kan beslutas och utforas av den enskilde djuraägaren utan att störa den kollektiva renskötseln. Urval är en åtgärd som ger effekt först på längre sikt och därför kräver en konsekvent insats under en längre tid.
Directory of Open Access Journals (Sweden)
Shivananda B. Nayak
2015-01-01
Full Text Available Background: The aim of this study was to determine the differences amongst the anthropometric measurements, lipid profile, blood pressure and body shape in diabetics as well as non-diabetics. Methods: This was a cross-sectional study comprised of 309 subjects with 91 males and 218 females. Of this, there were 217 diabetics and 92 non-diabetics. The sample was taken from three hospitals in Trinidad. Lipid profile and blood pressure were taken from each facility's physician's notes while anthropometric measurements were taken from the patients themselves. Results: The diabetic group had elevated body mass index and waist to hip ratios were significant (P <0.05 when compared to non-diabetics. There was no significant association of lipid profile, blood pressure, waist circumference and waist to height ratios between diabetics and non-diabetics. As age increased, the prevalence of type 2 diabetes mellitus was more common. Out of 217 diabetics, 173 were of East Indian descent. With regards to gender, more males were found to be diabetics resulting from having an android body shape as compared to females (gynoid body shape. Conclusion: It was found that of all the anthropometric measurements used, waist to hip ratio was found to be the most effective indicator of type 2 diabetes mellitus in Trinidadians, while body mass index was found to be the least effective indicator. [Int J Res Med Sci 2015; 3(1.000: 256-259
Research on shape optimization of CSG dams
Directory of Open Access Journals (Sweden)
Xin CAI
2011-12-01
Full Text Available The multi-objective optimization method was used for shape optimization of cement sand and gravel (CSG dams in this study. The economic efficiency, the sensitivities of maximum horizontal displacement and maximum settlement of the dam to water level changes, the overall stability, and the overall strength security were taken into account during the optimization process. Three weight coefficient selection schemes were adopted to conduct shape optimization of a dam, and the case studies lead to the conclusion that both the upstream and downstream dam slope ratios for the optimal cross-section equal 1:0.7, which is consistent with the empirically observed range of 1:0.6 to 1:0.8 for the upstream and downstream dam slope ratios of CSG dams. Therefore, the present study is of certain reference value for designing CSG dams.
[SIAM conference on optimization
Energy Technology Data Exchange (ETDEWEB)
1992-05-10
Abstracts are presented of 63 papers on the following topics: large-scale optimization, interior-point methods, algorithms for optimization, problems in control, network optimization methods, and parallel algorithms for optimization problems.
Fabrication of High Aspect Ratio SU-8 Structures for Integrated Spectrometers
DEFF Research Database (Denmark)
Anhøj, Thomas Aarøe
2007-01-01
of photolithography. Successful fabrication of re ection gratings requires a high degree of precision in the photolithographic process. The fabrication process has thus been optimized by optimizing the photolithographic process for fabrication of high aspect ratio structures, i.e. structures with details...... that are small compared to the height of the structure. A decisive factor is the ability of the process to separate closely- spaced structures. The primary measure of quality is thus the aspect ratio of the narrowest trench which it is possible to resolve in the lithographic process. The optimization...
GAS AND OIL POWER DISTRIBUTION RATIO OF A NEW HYDRAULIC BREAKER
Institute of Scientific and Technical Information of China (English)
ZHAO Hongqiang; LI Meixiang; GAO Bin; HE Qinghua
2007-01-01
The working principle of a new hydraulic breaker operated jointly by gas and hydraulic flow which has a reasonable structure, high efficiency and long piston life-span, is analyzed, and the optimal power distribution ratio of the sealed nitrogen gas to the high-pressure oil in the process of piston impacting is studied. Through theoretical analysis, optimization simulation and detailed calculation, it is determined that the impact system has optimal mechanical performance and highest efficiency when the distribution ratio Φis between 0.3 and 0.5. The theoretical result is also verified by repeated tests.
Directory of Open Access Journals (Sweden)
Ju-Young Hong
2016-03-01
Full Text Available BackgroundMost type 2 diabetes mellitus patients are obese and have obesity related vascular complications. Exenatide treatment is well known for both decreasing glycated hemoglobin levels and reduction in body weight. So, this study aimed to determine the effects of exenatide on body composition, glycated hemoglobin levels, and vascular stiffness in obese type 2 diabetes mellitus patients.MethodsFor 1 month, 32 obese type 2 diabetes mellitus patients were administered 5 µg of exenatide twice daily. The dosage was then increased to 10 µg. Patients' height, body weight, glycated hemoglobin levels, lipid profile, pulse wave velocity (PWV, body mass index, fat mass, and muscle mass were measured by using Inbody at baseline and after 3 months of treatment.ResultsAfter 3 months of treatment, glycated hemoglobin levels decreased significantly (P=0.007. Triglyceride, total cholesterol, and low density lipoprotein levels decreased, while aspartate aminotransferase and alanine aminotransferase levels were no change. Body weight, and fat mass decreased significantly (P=0.002 and P=0.001, respectively, while interestingly, muscle mass did not decrease (P=0.289. In addition to, Waist-to-hip ratio and aortic PWV decreased significantly (P=0.006 and P=0.001, respectively.ConclusionEffects of short term exenatide use in obese type 2 diabetes mellitus with cardiometabolic high risk patients not only reduced body weight without muscle mass loss, body fat mass, and glycated hemoglobin levels but also improved aortic PWV in accordance with waist to hip ratio.
New genetic loci link adipose and insulin biology to body fat distribution.
Shungin, Dmitry; Winkler, Thomas W; Croteau-Chonka, Damien C; Ferreira, Teresa; Locke, Adam E; Mägi, Reedik; Strawbridge, Rona J; Pers, Tune H; Fischer, Krista; Justice, Anne E; Workalemahu, Tsegaselassie; Wu, Joseph M W; Buchkovich, Martin L; Heard-Costa, Nancy L; Roman, Tamara S; Drong, Alexander W; Song, Ci; Gustafsson, Stefan; Day, Felix R; Esko, Tonu; Fall, Tove; Kutalik, Zoltán; Luan, Jian'an; Randall, Joshua C; Scherag, André; Vedantam, Sailaja; Wood, Andrew R; Chen, Jin; Fehrmann, Rudolf; Karjalainen, Juha; Kahali, Bratati; Liu, Ching-Ti; Schmidt, Ellen M; Absher, Devin; Amin, Najaf; Anderson, Denise; Beekman, Marian; Bragg-Gresham, Jennifer L; Buyske, Steven; Demirkan, Ayse; Ehret, Georg B; Feitosa, Mary F; Goel, Anuj; Jackson, Anne U; Johnson, Toby; Kleber, Marcus E; Kristiansson, Kati; Mangino, Massimo; Mateo Leach, Irene; Medina-Gomez, Carolina; Palmer, Cameron D; Pasko, Dorota; Pechlivanis, Sonali; Peters, Marjolein J; Prokopenko, Inga; Stančáková, Alena; Ju Sung, Yun; Tanaka, Toshiko; Teumer, Alexander; Van Vliet-Ostaptchouk, Jana V; Yengo, Loïc; Zhang, Weihua; Albrecht, Eva; Ärnlöv, Johan; Arscott, Gillian M; Bandinelli, Stefania; Barrett, Amy; Bellis, Claire; Bennett, Amanda J; Berne, Christian; Blüher, Matthias; Böhringer, Stefan; Bonnet, Fabrice; Böttcher, Yvonne; Bruinenberg, Marcel; Carba, Delia B; Caspersen, Ida H; Clarke, Robert; Daw, E Warwick; Deelen, Joris; Deelman, Ewa; Delgado, Graciela; Doney, Alex S F; Eklund, Niina; Erdos, Michael R; Estrada, Karol; Eury, Elodie; Friedrich, Nele; Garcia, Melissa E; Giedraitis, Vilmantas; Gigante, Bruna; Go, Alan S; Golay, Alain; Grallert, Harald; Grammer, Tanja B; Gräßler, Jürgen; Grewal, Jagvir; Groves, Christopher J; Haller, Toomas; Hallmans, Goran; Hartman, Catharina A; Hassinen, Maija; Hayward, Caroline; Heikkilä, Kauko; Herzig, Karl-Heinz; Helmer, Quinta; Hillege, Hans L; Holmen, Oddgeir; Hunt, Steven C; Isaacs, Aaron; Ittermann, Till; James, Alan L; Johansson, Ingegerd; Juliusdottir, Thorhildur; Kalafati, Ioanna-Panagiota; Kinnunen, Leena; Koenig, Wolfgang; Kooner, Ishminder K; Kratzer, Wolfgang; Lamina, Claudia; Leander, Karin; Lee, Nanette R; Lichtner, Peter; Lind, Lars; Lindström, Jaana; Lobbens, Stéphane; Lorentzon, Mattias; Mach, François; Magnusson, Patrik K E; Mahajan, Anubha; McArdle, Wendy L; Menni, Cristina; Merger, Sigrun; Mihailov, Evelin; Milani, Lili; Mills, Rebecca; Moayyeri, Alireza; Monda, Keri L; Mooijaart, Simon P; Mühleisen, Thomas W; Mulas, Antonella; Müller, Gabriele; Müller-Nurasyid, Martina; Nagaraja, Ramaiah; Nalls, Michael A; Narisu, Narisu; Glorioso, Nicola; Nolte, Ilja M; Olden, Matthias; Rayner, Nigel W; Renstrom, Frida; Ried, Janina S; Robertson, Neil R; Rose, Lynda M; Sanna, Serena; Scharnagl, Hubert; Scholtens, Salome; Sennblad, Bengt; Seufferlein, Thomas; Sitlani, Colleen M; Vernon Smith, Albert; Stirrups, Kathleen; Stringham, Heather M; Sundström, Johan; Swertz, Morris A; Swift, Amy J; Syvänen, Ann-Christine; Tayo, Bamidele O; Thorand, Barbara; Thorleifsson, Gudmar; Tomaschitz, Andreas; Troffa, Chiara; van Oort, Floor V A; Verweij, Niek; Vonk, Judith M; Waite, Lindsay L; Wennauer, Roman; Wilsgaard, Tom; Wojczynski, Mary K; Wong, Andrew; Zhang, Qunyuan; Hua Zhao, Jing; Brennan, Eoin P; Choi, Murim; Eriksson, Per; Folkersen, Lasse; Franco-Cereceda, Anders; Gharavi, Ali G; Hedman, Åsa K; Hivert, Marie-France; Huang, Jinyan; Kanoni, Stavroula; Karpe, Fredrik; Keildson, Sarah; Kiryluk, Krzysztof; Liang, Liming; Lifton, Richard P; Ma, Baoshan; McKnight, Amy J; McPherson, Ruth; Metspalu, Andres; Min, Josine L; Moffatt, Miriam F; Montgomery, Grant W; Murabito, Joanne M; Nicholson, George; Nyholt, Dale R; Olsson, Christian; Perry, John R B; Reinmaa, Eva; Salem, Rany M; Sandholm, Niina; Schadt, Eric E; Scott, Robert A; Stolk, Lisette; Vallejo, Edgar E; Westra, Harm-Jan; Zondervan, Krina T; Amouyel, Philippe; Arveiler, Dominique; Bakker, Stephan J L; Beilby, John; Bergman, Richard N; Blangero, John; Brown, Morris J; Burnier, Michel; Campbell, Harry; Chakravarti, Aravinda; Chines, Peter S; Claudi-Boehm, Simone; Collins, Francis S; Crawford, Dana C; Danesh, John; de Faire, Ulf; de Geus, Eco J C; Dörr, Marcus; Erbel, Raimund; Eriksson, Johan G; Farrall, Martin; Ferrannini, Ele; Ferrières, Jean; Forouhi, Nita G; Forrester, Terrence; Franco, Oscar H; Gansevoort, Ron T; Gieger, Christian; Gudnason, Vilmundur; Haiman, Christopher A; Harris, Tamara B; Hattersley, Andrew T; Heliövaara, Markku; Hicks, Andrew A; Hingorani, Aroon D; Hoffmann, Wolfgang; Hofman, Albert; Homuth, Georg; Humphries, Steve E; Hyppönen, Elina; Illig, Thomas; Jarvelin, Marjo-Riitta; Johansen, Berit; Jousilahti, Pekka; Jula, Antti M; Kaprio, Jaakko; Kee, Frank; Keinanen-Kiukaanniemi, Sirkka M; Kooner, Jaspal S; Kooperberg, Charles; Kovacs, Peter; Kraja, Aldi T; Kumari, Meena; Kuulasmaa, Kari; Kuusisto, Johanna; Lakka, Timo A; Langenberg, Claudia; Le Marchand, Loic; Lehtimäki, Terho; Lyssenko, Valeriya; Männistö, Satu; Marette, André; Matise, Tara C; McKenzie, Colin A; McKnight, Barbara; Musk, Arthur W; Möhlenkamp, Stefan; Morris, Andrew D; Nelis, Mari; Ohlsson, Claes; Oldehinkel, Albertine J; Ong, Ken K; Palmer, Lyle J; Penninx, Brenda W; Peters, Annette; Pramstaller, Peter P; Raitakari, Olli T; Rankinen, Tuomo; Rao, D C; Rice, Treva K; Ridker, Paul M; Ritchie, Marylyn D; Rudan, Igor; Salomaa, Veikko; Samani, Nilesh J; Saramies, Jouko; Sarzynski, Mark A; Schwarz, Peter E H; Shuldiner, Alan R; Staessen, Jan A; Steinthorsdottir, Valgerdur; Stolk, Ronald P; Strauch, Konstantin; Tönjes, Anke; Tremblay, Angelo; Tremoli, Elena; Vohl, Marie-Claude; Völker, Uwe; Vollenweider, Peter; Wilson, James F; Witteman, Jacqueline C; Adair, Linda S; Bochud, Murielle; Boehm, Bernhard O; Bornstein, Stefan R; Bouchard, Claude; Cauchi, Stéphane; Caulfield, Mark J; Chambers, John C; Chasman, Daniel I; Cooper, Richard S; Dedoussis, George; Ferrucci, Luigi; Froguel, Philippe; Grabe, Hans-Jörgen; Hamsten, Anders; Hui, Jennie; Hveem, Kristian; Jöckel, Karl-Heinz; Kivimaki, Mika; Kuh, Diana; Laakso, Markku; Liu, Yongmei; März, Winfried; Munroe, Patricia B; Njølstad, Inger; Oostra, Ben A; Palmer, Colin N A; Pedersen, Nancy L; Perola, Markus; Pérusse, Louis; Peters, Ulrike; Power, Chris; Quertermous, Thomas; Rauramaa, Rainer; Rivadeneira, Fernando; Saaristo, Timo E; Saleheen, Danish; Sinisalo, Juha; Slagboom, P Eline; Snieder, Harold; Spector, Tim D; Thorsteinsdottir, Unnur; Stumvoll, Michael; Tuomilehto, Jaakko; Uitterlinden, André G; Uusitupa, Matti; van der Harst, Pim; Veronesi, Giovanni; Walker, Mark; Wareham, Nicholas J; Watkins, Hugh; Wichmann, H-Erich; Abecasis, Goncalo R; Assimes, Themistocles L; Berndt, Sonja I; Boehnke, Michael; Borecki, Ingrid B; Deloukas, Panos; Franke, Lude; Frayling, Timothy M; Groop, Leif C; Hunter, David J; Kaplan, Robert C; O'Connell, Jeffrey R; Qi, Lu; Schlessinger, David; Strachan, David P; Stefansson, Kari; van Duijn, Cornelia M; Willer, Cristen J; Visscher, Peter M; Yang, Jian; Hirschhorn, Joel N; Zillikens, M Carola; McCarthy, Mark I; Speliotes, Elizabeth K; North, Kari E; Fox, Caroline S; Barroso, Inês; Franks, Paul W; Ingelsson, Erik; Heid, Iris M; Loos, Ruth J F; Cupples, L Adrienne; Morris, Andrew P; Lindgren, Cecilia M; Mohlke, Karen L
2015-02-12
Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms.
Weeks, Benjamin K; Purvis, Meredith; Beck, Belinda R
2016-11-01
The nature of physical activity that benefits bone is traditionally thought to differ from that benefiting cardiovascular health. Accordingly, exercise recommendations for improving bone health and cardiovascular health are largely incongruent. Our aim was to determine the associations between high-impact physical activity participation and both cardiovascular disease risk factors and bone mass. We recruited 94 men and women (age 34.0 ± 13.3 years) to undergo measures of cardiovascular disease risk (BMI, total cholesterol, fasting blood glucose, waist-to-hip ratio, and mean arterial pressure) and dual-energy X-ray absorptiometry (DXA XR-800, Norland) measures of bone mass (femoral neck, lumbar spine, and whole body BMD) and body composition (whole body lean mass and fat mass). Physical activity participation was estimated using the bone-specific physical activity questionnaire (BPAQ). Those in the upper tertile for current BPAQ score exhibited lower total cholesterol, waist-to-hip ratio, and mean arterial pressure than those in the lower tertiles (P high-impact physical activity as captured by the BPAQ may be beneficial for both bone health and for attenuating cardiovascular disease risk.
Cicchella, Antonio; Jürimäe, Toivo; Stefanelli, Claudio; Purge, Priit; Lätt, Evelin; Saar, Meeli
2014-06-01
The aim of this study was to investigate the correlations of leptin with values of skinfold thicknesses and circumferences in 10-12-year-old boys (N = 248) and these correlations were additionally studied in boys with different BMI subgroups (normal N = 190, overweight N = 34 and obese N = 24). In total, 9 skinfolds and 13 circumferences were measured using the recommendations of ISAK. Fasting leptin concentrations were also determined. No significant differences emerged between the three subgroups in age and Tanner stage. Skinfold thicknesses, circumferences and leptin concentrations were significantly higher in overweight and obese groups. In the total group, the correlation (partial correlation, eliminating age and Tanner stage) between separate skinfold thicknesses and leptin was higher than r = 0.70. The sum of 9 skinfold thicknesses correlated significantly to leptin in all groups (r = 0.558-0.779). In the obese group, triceps, biceps and front thigh skinfold thicknesses did not correlate (p > 0.05) with leptin. In the total group, all measured circumferences correlated significantly to leptin concentration (r = 0.328-0.724). However, in the obese group, the measured circumferences did not correlate to leptin (p > 0.05). Waist-to-hip ratio correlated with leptin only in the total group of boys. It was concluded that as a rule, close correlations emerged between leptin and skinfold thicknesses and circumferences. The strongest correlation with leptin was found with the sum of 9 skinfolds and waist-to-hip ratio.
Kim, Dongwon; Ham, Ok Kyung; Kang, Changwan; Jun, Eunmi
2014-04-01
To examine the effects of auricular acupressure with Sinapsis alba seeds on obesity and self-efficacy. Randomized controlled trial. College settings located in metropolitan areas of Korea. A total of 49 female college students who were overweight or obese (body-mass index [BMI] ≥25.0 kg/m(2)) were recruited and randomly assigned to the experimental group (n=25) or the control group (n=24). The experimental group applied three S. alba seeds to each of five auricular points (Shenmen, mouth, stomach, endocrine, and small intestine points). These participants were asked to stimulate those points 10 times at a rate of two times per second 30 minutes before mealtime, three times daily, for 1 month. They performed the procedure for each earlobe for alternating weeks (a total of 2 weeks' treatment for each ear). The obesity index included weight (kg), BMI (kg/m(2)), percentage body fat, and waist-to-hip ratio. Self-efficacy was measured by using a self-efficacy scale. Female students in the experimental group showed significant decreases in weight (t=10.76; p0.05) and waist-to-hip ratio (t=0.60; p>0.05) changes did not significantly differ between the two groups. These findings suggest that auricular acupressure using S. alba seeds may be an effective intervention for decreasing weight and BMI and increasing self-efficacy of overweight and obese individuals.
Effect of Yoga Exercises on the Body Composition of Fasting Females
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Fatemeh Zorofi
2013-11-01
Full Text Available The purpose of this study was to investigate the effect of one-month fasting along with yoga training on the body composition of novice female athletes. Twenty trained women were randomly assigned to experimental (n=10 and control (n=10 groups. The experimental group participated in yoga training classes for 4 weeks, two 60-min sessions per week; the control group did not participate in any regular exercise programs. This study was conducted on two fasting groups in the month of Ramadan, 2012. The study variables including body fat percentage, body mass index (BMI, waist circumference and waist-to-hip ratio (WHR were measured in three stages: a week before Ramadan, the fifteenth day of Ramadan, and a week after Ramadan. The results showed that BMI in the fasting yoga group decreased; however the changes of BMI in the control group were not significant. Also, subcutaneous fat showed significant reduction in both experimental and control groups, though the changes were more significant in the exercise group; also, the results showed that waist-to-hip ratio significantly changed in the experimental group. As to the results, yoga exercises along with fasting can help overweight people to experience ideal weight loss; also for the athletes who stop exercising in Ramadan, yoga can be used as an alternative to maintain their weight.
Effect of yoga exercises on the body composition of fasting females
Directory of Open Access Journals (Sweden)
Fatemeh Zorofi
2013-12-01
Full Text Available The purpose of this study was to investigate the effect of one-month fasting along with yoga training on the body composition of novice female athletes. Twenty trained women were randomly assigned to experimental (n=10 and control (n=10 groups. The experimental group participated in yoga training classes for 4 weeks, two 60-min sessions per week; the control group did not participate in any regular exercise programs. This study was conducted on two fasting groups in the month of Ramadan, 2012. The study variables including body fat percentage, body mass index (BMI, waist circumference and waist-to-hip ratio (WHR were measured in three stages: a week before Ramadan, the fifteenth day of Ramadan, and a week after Ramadan. The results showed that BMI in the fasting yoga group decreased; however the changes of BMI in the control group were not significant. Also, subcutaneous fat showed significant reduction in both experimental and control groups, though the changes were more significant in the exercise group; also, the results showed that waist-to-hip ratio significantly changed in the experimental group. As to the results, yoga exercises along with fasting can help overweight people to experience ideal weight loss; also for the athletes who stop exercising in Ramadan, yoga can be used as an alternative to maintain their weight.
Albertson, Ann M; Thompson, Douglas; Franko, Debra L; Holschuh, Norton M; Bauserman, Robert; Barton, Bruce A
2009-10-01
Cereal consumption is a common dietary behavior that has been associated with positive health outcomes. The objective of this study was to examine prospective associations between cereal intake in childhood and percent body fat, waist-to-hip ratio, lipid levels, and physical activity during late adolescence. In this longitudinal investigation (data collected 1987-1997), data were analyzed for the 2,379 girls who participated in the 10-year National Heart, Lung, and Blood Institute Growth and Health Study. The cumulative percent of days that each girl consumed cereal during childhood (based on 3-day food diaries collected during six study visits between ages 11.5 and 18.6 years) was examined in relation to percent body fat, waist-to-hip ratio, lipid levels, and physical activity measured at age 18.6 years. Results indicated that nearly all girls (90.1%) reported eating cereal and 18.7% reported eating cereal on half or more of the days reported in the food diaries. Girls who ate cereal on a greater percentage of days during childhood had lower percent body fat and total cholesterol, and were more likely to exhibit high levels of physical activity and less television viewing during Study Year 10 (P values<0.05). Further research should explore lifestyle issues related to cereal consumption.
Effect of Vitamin D Supplementation on Anthropometric Parameters in Patients With Metabolic Syndrome
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A Najarzadeh
2014-07-01
Methods:We utilized randomized controlled double – blind intervention, administering 300,000 IU vitamin D in divided doses of 6 50,000 IU pearls per day to the treatment group and 6 pearls of placebo to control group in the first week of intervention. Participants were 88 men and women aged 30 to 65 which had metabolic syndrome according to NCEP-ATP III definition and had referred to diabetes clinic of Emam Khomeini Hospital in Tehran. 25(OHD3 levels and anthropometric parameters including weight, BMI, waist circumference and waist to hip ratio were measured at the beginning and 3 months later. Results: There was a significant increase in serum 25(OHD3 levels from 20 ng/ml to 33 ng/ml at the end of the study in vitamin D supplemented group (P-value < 0.001. There was a significant decrease in waist circumference in the vitamin D supplemented group at the end of the study (P-value = 0.005. There was no significant difference in weight, BMI and waist to hip ratio in the groups at the end of the study. Conclusion: Improving vitamin D status decreases waist circumference but does not affect other anthropometric parameters in patients with metabolic syndrome.
Relationship between Visceral Adiposity and Plasma Adiponectin Concentration: Effect of Weight Loss
Directory of Open Access Journals (Sweden)
E Nasseri
2008-05-01
Full Text Available Background: Adiponectin is an anti-inflammatory and antiatherogenic protein that has a protective effect against atherosclerosis and diabetes. It is exclusively secreted by adipose tissue. Serum adiponectin levels are inversely associated with parameters of overall adiposity including body mass index (BMI, fat mass, and percentage of body fat. Methods: In a cross-sectional study of 76 women we sought to evaluate if adiponectin is associated primarily with central adiposity rather than overall adiposity. We also assessed adiponectin changes after weight loss in a subgroup of 42 obese subjects.Results: Waist to hip ratio (WHR, an index of central obesity, was the only variable independently associated to adiponectin (Beta= 0.25, P< 0.05. A mean increase of 8.2±24.2% in adiponectin concentration was observed in response to the dietary restriction and weight loss (P= 0.03. Our findings provide evidence for association of serum adiponectin level with visceral fat, represented by waist to hip ratio index.Conclusion: Moderate weight loss result in significant improvements in adiponectin concentration and provide another biological explanation for the beneficial effect of body weight loss on reducing cardiovascular and diabetes risks in obese patients.
Yao, W-M; Zhang, H-F; Zhu, Z-Y; Zhou, Y-L; Liang, N-X; Xu, D-J; Zhou, F; Sheng, Y-H; Yang, R; Gong, L; Yin, Z-J; Chen, F-K; Cao, K-J; Li, X-L
2013-04-01
Elevated levels of circulating triglycerides and increased arterial stiffness are associated with cardiovascular disease. Numerous studies have reported an association between levels of circulating triglycerides and arterial stiffness. We used Mendelian randomization to test whether this association is causal. We investigated the association between circulating triglyceride levels, the apolipoprotein A-V (ApoA5) -1131T>C single nucleotide polymorphism and brachial-ankle pulse wave velocity (baPWV) by examining data from 4421 subjects aged 18-74 years who were recruited from the Chinese population. baPWV was significantly associated with the levels of circulating triglycerides after adjusting for age, sex, body mass index (BMI), systolic blood pressure, heart rate, waist-to-hip ratio, antihypertensive treatment and diabetes mellitus status. The -1131C allele was associated with a 5% (95% confidence interval 3-8%) increase in circulating triglycerides (adjusted for age, sex, BMI, waist-to-hip ratio, diabetes mellitus and antihypertensive treatment). Instrumental variable analysis showed that genetically elevated levels of circulating triglycerides were not associated with increased baPWV. These results do not support the hypothesis that levels of circulating triglycerides have a causal role in the development of arterial stiffness.
Duarte, Gleison Vieira; de Oliveira, Maria de Fátima S. P.; Follador, Ivonise; Silva, Thadeu Santo; de Carvalho Filho, Edgar Marcelino
2016-01-01
BACKGROUND Psoriasis is an immune-mediated disease that manifests predominantly in the skin, although systemic involvement may also occur. Although associated comorbidities have long been recognized and despite several studies indicating psoriasis as an independent risk factor for cardiovascular events, little has been done in general medical practice regardind screening. In the United States, less than 50% of clinicians are aware of these recommendations. OBJECTIVE To identify the prevalence of these comorbidities in 296 patients followed up at a university dermatology clinic. METHODS Systematically investigated comorbidity frequencies were compared with general practitioners' registry frequencies. Clinical features correlated with comorbidities were also investigated. RESULTS High prevalences of systematically investigated comorbidities such as hypertension (30%) and dyslipidemia (26.5%) were documented. Conversely, data from general practitioners' records showed that 33% of dyslipidemia cases were undiagnosed and indicated possible underdiagnosis of some comorbidities. Furthermore, an association was found between: the number of comorbidities and psoriasis duration, age and high body mass index an association was found between the number of comorbidities and psoriasis duration, age, high body mass index, waist circumference or waist-to-hip ratio. (p<0.05). CONCLUSION Disease duration, age and high body mass index, waist circumference or waist-to-hip ratio are possible criteria for choosing which patients should be screened for comorbidities. Underdiagnosis of comorbidities by general practitioners highlights the need for a multidisciplinary approach in psoriasis management. PMID:28099594
β-3AR W64R Polymorphism and 30-Minute Post-Challenge Plasma Glucose Levels in Obese Children.
Verdi, Hasibe; Tulgar Kınık, Sibel; Yılmaz Yalçın, Yaprak; Muratoğlu Şahin, Nursel; Yazıcı, Ayşe Canan; Ataç, F Belgin
2015-03-01
In this study, we aimed to investigate the association of W64R polymorphism of the β3-adrenergic receptor gene (β-3AR) with childhood obesity and related pathologies. β-3AR gene W64R genotyping was carried out in 251 children aged 6-18 years. Of these subjects, 130 were obese (62 boys) and 121 were normal-weight (53 boys). In the obese group, fasting lipids, glucose and insulin levels were measured. Oral glucose tolerance test (OGTT) was performed in 75 of the obese patients. The frequency of W64R genotype was similar in obese and non-obese children. In obese children, relative body mass index, waist-to-hip ratio, serum lipid, glucose and insulin levels, as well as homeostasis model assessment of insulin resistance (HOMA-IR) scores were not different between Arg allele carriers (W64R and R64R) and noncarriers (W64W). In 75 obese children, OGTT results showed that Arg allele carriers had significantly higher 30-minute glucose levels (p=0.027). W64R polymorphism of the β-3AR gene is not associated with obesity and waist-to-hip ratio in Turkish children. Although there were no relationships between the genotypes and lipid, glucose/insulin levels or HOMA-IR, the presence of W64R variant seemed to have an unfavorable influence on early glucose excursion after glucose loading.
Integrated photonic power divider with arbitrary power ratios.
Xu, Ke; Liu, Lu; Wen, Xiang; Sun, Wenzhao; Zhang, Nan; Yi, Ningbo; Sun, Shang; Xiao, Shumin; Song, Qinghai
2017-02-15
Integrated optical power splitters are one of the fundamental building blocks in photonic integrated circuits. Conventional multimode interferometer-based power splitters are widely used as they have reasonable footprints and are easy to fabricate. However, it is challenging to realize arbitrary split ratios, especially for multi-outputs. In this Letter, an ultra-compact power splitter with a QR code-like nanostructure is designed by a nonlinear fast search method. The highly functional structure is composed of a number of freely designed square pixels with the size of 120×120 nm which could be either dielectric or air. The light waves are scattered by a number of etched squares with optimized locations, and the scattered waves superimpose at the outputs with the desired power ratio. We demonstrate 1×2 splitters with 1:1, 1:2, and 1:3 split ratios, and a 1×3 splitter with the ratio of 1:2:1. The footprint for all the devices is only 3.6×3.6 μm. Well-controlled split ratios are measured for all the cases. The measured transmission efficiencies of all the splitters are close to 80% over 30 nm wavelength range.
All passive photonic power divider with arbitrary split ratio
Xu, Ke; Wen, Xiang; Sun, Wenzhao; Zhang, Nan; Yi, Ningbo; Sun, Shang; Xiao, Shumin; Song, Qinghai
2016-01-01
Integrated optical power splitter is one of the fundamental building blocks in photonic integrated circuits (PIC). Conventional multimode interferometer based power splitter is widely used as it has reasonable footprint and is easy to fabricate. However, it is challenging to realize arbitrary split ratio especially for multi-outputs. In this work, an ultra-compact power splitter with a QR code-like nanostructure is designed by a nonlinear fast search method (FSM). The highly functional structure is composed of a number of freely designed square pixels with the size of 120nm x 120nm which could be either dielectric or air. The lightwaves are scattered by a number of etched squares with optimized locations and the scattered waves superimpose at the outputs with the desired power ratio. We demonstrate 1x2 splitters with 1:1, 1:2, 1:3 split ratios and a 1x3 splitter with the ratio of 1:2:1. The footprint for all the devices is only 3.6umx3.6 um. Well-controlled split ratios are measured for all the cases. The mea...
Energy Technology Data Exchange (ETDEWEB)
Bower, Stanley [Ford Motor Company, Dearborn, MI (United States)
2011-12-31
A 5.0L V8 twin-turbocharged direct injection engine was designed, built, and tested for the purpose of assessing the fuel economy and performance in the F-Series pickup of the Dual Fuel engine concept and of an E85 optimized FFV engine. Additionally, production 3.5L gasoline turbocharged direct injection (GTDI) EcoBoost engines were converted to Dual Fuel capability and used to evaluate the cold start emissions and fuel system robustness of the Dual Fuel engine concept. Project objectives were: to develop a roadmap to demonstrate a minimized fuel economy penalty for an F-Series FFV truck with a highly boosted, high compression ratio spark ignition engine optimized to run with ethanol fuel blends up to E85; to reduce FTP 75 energy consumption by 15% - 20% compared to an equally powered vehicle with a current production gasoline engine; and to meet ULEV emissions, with a stretch target of ULEV II / Tier II Bin 4. All project objectives were met or exceeded.
A Librarian's Primer on Financial Ratios.
Kerbel, Sandra Sandor
1982-01-01
Explains in simple terms the nature and function of a number of basic types of business and industrial financial ratios. An annotated list of five basic sources for ratios is included and a reference list and bibliography are attached. (JL)
Evaluation of a risk factor scoring model in screening for undiagnosed diabetes in China population
Institute of Scientific and Technical Information of China (English)
Jian-jun DONG; Neng-jun LOU; Jia-jun ZHAO; Zhong-wen ZHANG; Lu-lu QIU; Ying ZHOU; Lin LIAO
2011-01-01
Objective:To develop a risk scoring model for screening for undiagnosed type 2 diabetes in Chinese population.Methods:A total of 5348 subjects from two districts of Jinan City,Shandong Province,China were enrolled.Group A (2985) included individuals from east of the city and Group B (2363) from west of the city.Screening questionnaires and a standard oral glucose tolerance test (OGTr) were completed by all subjects.Based on the stepwise logistic regression analysis of Group A,variables were selected to establish the risk scoring model.The validity and effectiveness of this model were evaluated in Group B.Results:Based on stepwise logistic regression analysis performed with data of Group A,variables including age,body mass index (BMI),waist-to-hip ratio (WHR),systolic pressure,diastolic pressure,heart rate,family history of diabetes,and history of high glucose were accepted into the risk scoring model.The risk for having diabetes increased along with aggregate scores.When Youden index was closest to 1,the optimal cutoff value was set up at 51.At this point,the diabetes risk scoring model could identify diabetes patients with a sensitivity of 83.3％ and a specificity of 66.5％,making the positive predictive value 12.83％and negative predictive value 98.53％.We compared our model with the Finnish and Danish model and concluded that our model has superior validity in Chinese population.Conclusions:Our diabetes risk scoring model has satisfactory sensitivity and specificity for identifying undiagnosed diabetes in our population,which might be a simple and practical tool suitable for massive diabetes screening.
Determining Extinction Ratio Of A Laser Diode
Unger, Glenn L.
1992-01-01
Improved technique to determine extinction ratio of pulsed laser diode based partly on definition of extinction ratio applicable to nonideal laser pulses. Heretofore, determinations involved assumption of ideal laser pulses, and neglected optical power from background light. Because power fluctuates during real pulse, more realistic to define extinction ratio in terms of energy obtained.
Multiple Satellite Trajectory Optimization
2004-12-01
SOLVING OPTIMAL CONTROL PROBLEMS ........................................5...OPTIMIZATION A. SOLVING OPTIMAL CONTROL PROBLEMS The driving principle used to solve optimal control problems was first formalized by the Soviet...methods and processes of solving optimal control problems , this section will demonstrate how the formulations work as expected. Once coded, the
Antenna optimization using Particle Swarm Optimization algorithm
Directory of Open Access Journals (Sweden)
Golubović Ružica M.
2006-01-01
Full Text Available We present the results for two different antenna optimization problems that are found using the Particle Swarm Optimization (PSO algorithm. The first problem is finding the maximal forward gain of a Yagi antenna. The second problem is finding the optimal feeding of a broadside antenna array. The optimization problems have 6 and 20 optimization variables, respectively. The preferred values of the parameters of the PSO algorithm are found for presented problems. The results show that the preferred parameters of PSO are somewhat different for optimization problems with different number of dimensions of the optimization space. The results that are found using the PSO algorithm are compared with the results that are found using other optimization algorithms, in order to estimate the efficiency of the PSO.
Institute of Scientific and Technical Information of China (English)
闫立辉; 陕忠远; 孙颖; 阎英; 卢智泉
2015-01-01
目的：探讨中老年人体质指数（BMI）、腰臀比（WHR）与食管癌的关系。方法采用以医院为基础的病例对照研究。选取2012年9月—2013年3月入住辽宁医学院附属第一医院、附属第三医院和锦州市中心医院肿瘤科和胸外科病房，经临床组织病理学诊断为食管癌，年龄≥40岁的282例食管癌患者为病例组；选取与病例同期入住相同医院，未患食管及其他消化系统癌症，罹患其他疾病的282例患者为对照组。采用标准调查表对患者进行面对面调查，同时对身高、体质量、腰围、臀围进行测量，并计算 BMI 及 WHR。结果两组患者的年龄、性别、职业、文化程度、居住地及高血压史间差异均无统计学意义（p >0.05）；家庭人均月收入、吸烟、饮酒及糖尿病史间差异均有统计学意义（p 0.95患者发生食管癌的危险性是对照组 WHR 0.94患者发生食管癌的危险性分别升高4.8%、32.6%和36.5%。结论 BMI、WHR是发生食管癌的重要危险因素，超重和肥胖的人群发生食管癌的危险性明显增加，维持正常体质量可能是食管癌发病的保护因素。%[AbstraCt] ObjeCtive To explore the association between body mass index(BMI),waist to hip ratio(WHR)and esophageal cancer risk in middle aged and elderly people. Methods A hospital _ based case _ control study was conducted. Cases (n = 282)were esophageal cancer patients who were hospitalized in department of oncology and chest surgery,the First Affiliated Hospital and the Third Affiliated Hospital,Liaoning Medical University and Central Hospital,Jinzhou from September,2012 to March,2013 and confirmed by clinical histopathological examination,and controls(n = 282)were patients admitted to the same hospital for different diseases. All of them received face _ to _ face investigation with a standardized questionnaire. Their height and weight,waist circumference and hip circumference were
Efficient Computation of Optimal Trading Strategies
Boyarshinov, Victor
2010-01-01
Given the return series for a set of instruments, a \\emph{trading strategy} is a switching function that transfers wealth from one instrument to another at specified times. We present efficient algorithms for constructing (ex-post) trading strategies that are optimal with respect to the total return, the Sterling ratio and the Sharpe ratio. Such ex-post optimal strategies are useful analysis tools. They can be used to analyze the "profitability of a market" in terms of optimal trading; to develop benchmarks against which real trading can be compared; and, within an inductive framework, the optimal trades can be used to to teach learning systems (predictors) which are then used to identify future trading opportunities.
Spectral ratio method for measuring emissivity
Watson, K.
1992-01-01
The spectral ratio method is based on the concept that although the spectral radiances are very sensitive to small changes in temperature the ratios are not. Only an approximate estimate of temperature is required thus, for example, we can determine the emissivity ratio to an accuracy of 1% with a temperature estimate that is only accurate to 12.5 K. Selecting the maximum value of the channel brightness temperatures is an unbiased estimate. Laboratory and field spectral data are easily converted into spectral ratio plots. The ratio method is limited by system signal:noise and spectral band-width. The images can appear quite noisy because ratios enhance high frequencies and may require spatial filtering. Atmospheric effects tend to rescale the ratios and require using an atmospheric model or a calibration site. ?? 1992.
High on/off ratio ns laser pulses for a triggered single-photon source
Jin, Gang; He, Jun; Wang, Junmin
2016-01-01
852nm nano-second laser pulse chain with a high on/off ratio is generated via chopping a continuous-wave laser beam by using of a Mach-Zehnder-type electro-optic intensity modulator (MZ-EOIM). Detailed analysis and dependence of the on/off ratio on the splitting ratio, the co-splitting ratio, and the arms loss of MZ-EIOM are presented. By optimizing the polarization of incident laser beam and stabilizing MZ-EOIM temperature, the static on/off ratio of 12600:1 is achieved. Also the dynamic on/off ratios versus the pulse repetition rate and the pulse duty cycle are measured and discussed. This high on/off ratio ns pulsed laser system has served as the excitation pulse source for a triggered single-photon source based on trapped single cesium atom, which reveals a representative anti-bunching.
Selection Relaying at Low Signal to Noise Ratios
Rajawat, Ketan
2007-01-01
Performance of cooperative diversity schemes at Low Signal to Noise Ratios (LSNR) was recently studied by Avestimehr et. al. [1] who emphasized the importance of diversity gain over multiplexing gain at low SNRs. It has also been pointed out that continuous energy transfer to the channel is necessary for achieving the max-flow min-cut bound at LSNR. Motivated by this we propose the use of Selection Decode and Forward (SDF) at LSNR and analyze its performance in terms of the outage probability. We also propose an energy optimization scheme which further brings down the outage probability.
OPTIMAL DESIGN OF SMART ANTENNA ARRAY
Institute of Scientific and Technical Information of China (English)
Gao Feng; Liu Qizhong; Shan Runhong; Zhang Hou
2004-01-01
This letter investigates an efficient design procedure integrating the Genetic Algorithm (GA) with the Finite Difference Time Domain (FDTD) for the fast optimal design of Smart Antenna Arrays (SAA). The FDTD is used to analyze SAA with mutual coupling. Then,on the basis of the Maximal Signal to Noise Ratio (MSNR) criteria, the GA is applied to the optimization of weighting elements and structure of SAA. Finally, the effectiveness of the analysis is evaluated by experimental antenna arrays.
The Investigation of EDM Parameters on Electrode Wear Ratio
Directory of Open Access Journals (Sweden)
Reza Atefi
2012-05-01
Full Text Available Electrical Discharge Machining (EDM is a well-established machining option for manufacturing geometrically complex or hard material parts that are extremely difficult-to-machine by conventional machining processes. The non-contact machining technique has been continuously evolving from a mere tool and die making process. In this study, the influence of different electro discharge machining parameters (current, pulse on-time, pulse off-time, arc voltage on the electrode wear ratio as a result of application copper electrode to hot work steel DIN1.2344 has been investigated. Design of the experiment was chosen as full factorial. Artificial neural network has been used to choose proper machining parameters and to reach certain electrode wear ratio. Finally a hybrid model has been designed to reduce the artificial neural network errors. The experiment results indicated a good performance of proposed method in optimization of such a complex and non-linear problems.
Adaptive Air-Fuel Ratio Control with MLP Network
Institute of Scientific and Technical Information of China (English)
Shi-Wei Wang; Ding-Li Yu
2005-01-01
This paper presents an application of adaptive neural network model-based predictive control (MPC) to the air-fuel ratio of an engine simulation. A multi-layer perceptron (MLP) neural network is trained using two on-line training algorithms: a back propagation algorithm and a recursive least squares (RLS) algorithm. It is used to model parameter uncertainties in the nonlinear dynamics of internal combustion (IC) engines. Based on the adaptive model, an MPC strategy for controlling air-fuel ratio is realized, and its control performance compared with that of a traditional PI controller.A reduced Hessian method, a newly developed sequential quadratic programming (SQP) method for solving nonlinear programming (NLP) problems, is implemented to speed up nonlinear optimization in the MPC.
Ecological optimization of endoreversible chemical engines
Directory of Open Access Journals (Sweden)
Dan Xia, Lingen Chen, Fengrui Sun
2011-09-01
Full Text Available Optimal ecological performances of endoreversible chemical engine cycles with both linear and diffusive mass transfer laws are derived by taking an ecological optimization criterion as the objective, which consists of maximizing a function representing the best compromise between the power output and entropy production rate of the chemical engines. Numerical examples are given to show the effects of mass-reservoir chemical potential ratio and mass-transfer coefficient ratio on the ecological function versus the efficiency characteristic of the cycles. The results can provide some theoretical guidelines for the design of practical chemical engines.
Optimal Disturbance Accommodation with Limited Model Information
Farokhi, F; Johansson, K H
2011-01-01
The design of optimal dynamic disturbance-accommodation controller with limited model information is considered. We adapt the family of limited model information control design strategies, defined earlier by the authors, to handle dynamic-controllers. This family of limited model information design strategies construct subcontrollers distributively by accessing only local plant model information. The closed-loop performance of the dynamic-controllers that they can produce are studied using a performance metric called the competitive ratio which is the worst case ratio of the cost a control design strategy to the cost of the optimal control design with full model information.
Optimization modeling with spreadsheets
Baker, Kenneth R
2015-01-01
An accessible introduction to optimization analysis using spreadsheets Updated and revised, Optimization Modeling with Spreadsheets, Third Edition emphasizes model building skills in optimization analysis. By emphasizing both spreadsheet modeling and optimization tools in the freely available Microsoft® Office Excel® Solver, the book illustrates how to find solutions to real-world optimization problems without needing additional specialized software. The Third Edition includes many practical applications of optimization models as well as a systematic framework that il
Protein to energy ratios in goldfish (Carassius auratus diets
Directory of Open Access Journals (Sweden)
Cristielle Nunes Souto
2013-12-01
Full Text Available The optimal dietary digestible protein to energy ratio is critical for the success of fish farming. Considering that it provides the proper development of the animals, this study was undertaken to evaluate the effects of different dietary digestible protein to energy ratio in diets for goldfish fingerlings. Diets were formulated to contain 28.0, 35.0, 42.0 and 49.0% DP and 3,600 and 3,200 kcal/kg. The growth parameters evaluated were daily weight gain (DWG, feed intake (FI, feed conversion ratio (FCR, protein efficiency ratio (PER, protein productive value (PPV and energy retention ratio (ERR and specific growth rate (SGR. Regardless FI, all the parameters were affected by protein and energy levels and interaction between both factors was observed. The second-order polynomial equation best fitted to the DWG, SGR, FCR, PER and ERR with estimated requirement values of 38.81, 38.85, 41.05, 41.80 and 39.39% DP, respectively, at the 3,200 kcal/kg. A second-order polynomial model was significant only for the ERR data at the 3,600 kcal/kg with an estimated requirement value of 36.45% DP. Generally, fish fed diets containing 3,200 kcal/kg had better growth performance than fish fed 3,600 kcal/kg (P<0.01, indicating a higher feed efficiency. A 3,200 kcal/kg diet seems to be the proper DE level for meeting goldfish requirement for highest weight gain. Based on this experimental condition, we recommend the use of DP levels between 38.0-40.0% in diets for goldfish with 3,200 kcal/kg or a dietary protein to energy ratio between 119-125 mg/kcal DE.
Energy Technology Data Exchange (ETDEWEB)
Buchert, Ralph; Lange, Catharina [Charite - Universitaetsmedizin Berlin, Department of Nuclear Medicine, Berlin (Germany); Kluge, Andreas; Bronzel, Marcus [ABX-CRO advanced pharmaceutical services Forschungsgesellschaft m.b.H., Dresden (Germany); Tossici-Bolt, Livia [University Hospital Southampton NHS Foundation Trust, Department of Medical Physics, Southampton (United Kingdom); Dickson, John [University College London Hospital NHS Foundation Trust, Institute of Nuclear Medicine, London (United Kingdom); Asenbaum, Susanne [Medical University of Vienna, Department of Nuclear Medicine, Vienna (Austria); Booij, Jan [University of Amsterdam, Department of Nuclear Medicine, Academic Medical Centre, Amsterdam (Netherlands); Kapucu, L. Oezlem Atay [Gazi University, Department of Nuclear Medicine, Faculty of Medicine, Ankara (Turkey); Svarer, Claus [Rigshospitalet and University of Copenhagen, Neurobiology Research Unit, Copenhagen (Denmark); Koulibaly, Pierre-Malick [University of Nice-Sophia Antipolis, Nuclear Medicine Department, Centre Antoine Lacassagne, Nice (France); Nobili, Flavio [University of Genoa, Department of Neuroscience (DINOGMI), Clinical Neurology Unit, Genoa (Italy); Pagani, Marco [CNR, Institute of Cognitive Sciences and Technologies, Rome (Italy); Karolinska Hospital, Department of Nuclear Medicine, Stockholm (Sweden); Sabri, Osama [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Sera, Terez [University of Szeged, Department of Nuclear Medicine and Euromedic Szeged, Szeged (Hungary); Tatsch, Klaus [Municipal Hospital of Karlsruhe Inc, Department of Nuclear Medicine, Karlsruhe (Germany); Borght, Thierry vander [CHU Namur, IREC, Nuclear Medicine Division, Universite catholique de Louvain, Yvoir (Belgium); Laere, Koen van [University Hospital and K.U. Leuven, Nuclear Medicine, Leuven (Belgium); Varrone, Andrea [Karolinska University Hospital, Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm (Sweden); Iida, Hidehiro [National Cerebral and Cardiovascular Center - Research Institute, Osaka (Japan)
2016-07-15
Quantitative estimates of dopamine transporter availability, determined with [{sup 123}I]FP-CIT SPECT, depend on the SPECT equipment, including both hardware and (reconstruction) software, which limits their use in multicentre research and clinical routine. This study tested a dedicated reconstruction algorithm for its ability to reduce camera-specific intersubject variability in [{sup 123}I]FP-CIT SPECT. The secondary aim was to evaluate binding in whole brain (excluding striatum) as a reference for quantitative analysis. Of 73 healthy subjects from the European Normal Control Database of [{sup 123}I]FP-CIT recruited at six centres, 70 aged between 20 and 82 years were included. SPECT images were reconstructed using the QSPECT software package which provides fully automated detection of the outer contour of the head, camera-specific correction for scatter and septal penetration by transmission-dependent convolution subtraction, iterative OSEM reconstruction including attenuation correction, and camera-specific ''to kBq/ml'' calibration. LINK and HERMES reconstruction were used for head-to-head comparison. The specific striatal [{sup 123}I]FP-CIT binding ratio (SBR) was computed using the Southampton method with binding in the whole brain, occipital cortex or cerebellum as the reference. The correlation between SBR and age was used as the primary quality measure. The fraction of SBR variability explained by age was highest (1) with QSPECT, independently of the reference region, and (2) with whole brain as the reference, independently of the reconstruction algorithm. QSPECT reconstruction appears to be useful for reduction of camera-specific intersubject variability of [{sup 123}I]FP-CIT SPECT in multisite and single-site multicamera settings. Whole brain excluding striatal binding as the reference provides more stable quantitative estimates than occipital or cerebellar binding. (orig.)
PLC BASED RATIO CONTROLLER AND MATERIAL DISTRIBUTION SYSTEM
Directory of Open Access Journals (Sweden)
V. M. Badwaik Prof. V. M. Umale
2012-04-01
Full Text Available Automation in an industry using programmable logic controller (PLC can be enumerated by optimizing the use of process control equipment, decreases the response time for process and equipment contingencies, provides information about process status, manages process logic at the plant floor level and increases overall productivity and plant efficiency. The primary reason for designing such a system is to eliminate large cost involved in replacing complicated relay based machine control system & to reduce process time. Ratio control system is feed forward system where one variable is controlled in ratio to another to satisfy some higher level objectives. Two difference chemicals are supplied from different tanks in proper ratio by maintaining the flow of quantity. Then desired mixture is obtained &checks the ratio of composition if any unbalanced, controlled by controlled values of supply tanks. Then this mixture is distributed as per requirements. In Industries for ten machines, total cycle time with existing PLC based system is 75 sec. But our modified PLC based system total cycle time is improved as 45 sec. Hence total reach time of distribution system is improved.
On the Australian Bank Financial Ratio Analysis
Institute of Scientific and Technical Information of China (English)
张丽娜
2011-01-01
Financial ratios,despite some criticisms,are still used as a basis to evaluate a firm's performance,to make credit risk assessment decisions and classify firms into bankrupt and non-bankrupt groups.There are a great number of financial ratios which can be used for the evaluation of banks performance.Golin (2001) provides a list of over 80 ratios covering the major categories of capital,asset quality,profitability & efficiency,and liquidity & funding provides.
GLRT-Optimal Noncoherent Lattice Decoding
Ryan, Daniel J; Clarkson, I Vaughan L
2007-01-01
This paper presents new low-complexity lattice-decoding algorithms for noncoherent block detection of QAM and PAM signals over complex-valued fading channels. The algorithms are optimal in terms of the generalized likelihood ratio test (GLRT). The computational complexity is polynomial in the block length; making GLRT-optimal noncoherent detection feasible for implementation. We also provide even lower complexity suboptimal algorithms. Simulations show that the suboptimal algorithms have performance indistinguishable from the optimal algorithms. Finally, we consider block based transmission, and propose to use noncoherent detection as an alternative to pilot assisted transmission (PAT). The new technique is shown to outperform PAT.
Topology optimization design of space rectangular mirror
Qu, Yanjun; Wang, Wei; Liu, Bei; Li, Xupeng
2016-10-01
A conceptual lightweight rectangular mirror is designed based on the theory of topology optimization and the specific structure size is determined through sensitivity analysis and size optimization in this paper. Under the load condition of gravity along the optical axis, compared with the mirrors designed by traditional method using finite element analysis method, the performance of the topology optimization reflectors supported by peripheral six points are superior in lightweight ratio, structure stiffness and the reflective surface accuracy. This suggests that the lightweight method in this paper is effective and has potential value for the design of rectangular reflector.
Back Work Ratio of Brayton Cycle
Directory of Open Access Journals (Sweden)
Malaver de la Fuente M.
2010-07-01
Full Text Available This paper analizes the existing relation between temperatures, back work ratio and net work of Brayton cycle, a cycle that describes gas turbine engines performance. The application of computational soft ware helps to show the influence of back work ratio or coupling ratio, compressor and turbine in let temperatures in an ideal thermodynamical cycle. The results lead to deduce that the maximum value reached in back work ratio will depend on the ranges of maximum and minimal temperatures of Brayton cycle.
A ratio model of perceptual transparency.
Tommasi, M
1999-12-01
A ratio model of the achromatic transparency of a phenomenal surface on a bipartite background is proposed. The model asserts that transparency corresponds to the evaluation of the ratio of the lightness difference inside the transparent surface to the difference in reference lightness inside the background. It applies to both balanced and unbalanced transparency. The ratio model was compared experimentally with the previous perceptual model of achromatic transparency proposed by Metelli. Each model was tested by comparing the rated with the predicted transparency. Analysis shows that the ratio model provides better predictions of transparency than those provided by Metelli's model.
Force dynamics in fixed-ratio schedules.
Pinkston, Jonathan W; McBee, Lindsey N
2014-03-01
Fixed-ratio schedules are widely used in behavioral research. Although fixed-ratio schedules often conjure up relationships to work and effort, little is known about effort-related measures in these schedules. Early research had shown that force and effort of operant behavior vary systematically during the execution of ratio schedules, and the goal of the present study was to revisit early research on force dynamics in fixed-ratio schedules. Four rats earned sucrose by pressing an isometric force transducer. Presses produced sucrose after ten or twenty responses. In general, the force of responses increased then decreased systematically across the ratio. The possibility that decreases in force during ratio execution was due to a trade-off with the differential reinforcement of short inter-response times (IRT) was investigated in an additional condition where sucrose was made available according to a tandem fixed-ratio 19 inter-response (IRT)> t schedule. The tandem IRT requirement did not eliminate decreasing trends in force across the ratio; unexpectedly, the tandem requirement did eliminate increases in force early in the ratio, which may reflect sequence-level organization operating in the control of force dynamics.
Optimum Design of 1st Gear Ratio for 4WD Vehicles Based on Vehicle Dynamic Behaviour
Directory of Open Access Journals (Sweden)
M. H. Shojaeefard
2013-01-01
Full Text Available This paper presents an approach that allows optimizing gear ratio and vehicle dimension to achieve optimum gear transmission. Therefore, augmented Lagrangian multiplier method, defined as classical method, is utilized to find the optimum gear ratios and the corresponding number of gear teeth applied to all epicyclical gears. The new method is able to calculate and also to optimize the gear ratio based on dynamics of 4WD vehicles. Therefore, 4WD vehicles dynamic equations are employed assuming that the rear wheels or the front wheels are at the point of slip. In addition, a genetic algorithm is modified to preserve feasibility of the encountered solutions. The basic dimension of a sample commercial vehicle (2009 hummer H3 4dr AWD SUV and its gearbox are optimized, and then the effects of changing slip angle, wheel base, and engine torque on optimum vehicle dimension are analyzed.
Portfolio optimization retail investor
Directory of Open Access Journals (Sweden)
I. А. Kiseleva
2016-01-01
Full Text Available The article notes that the task of the investor's risk management is to, on the one hand, as much as possible to strive to achieve the criterion of risk level, and on the other hand, in any case not exceed it. Since the domestic theory of risk management is under development, the problem of the optimal ratio of "risk-income" becomes now of particular relevance. This article discusses the different distribution areas of the private investor in order to obtain the maximum profit. The analysis showed us the overall economic and political system of the country, as well as the legislative provision of guarantees to the investor. To obtain sufficient income and reduce losses it is important to maintain the optimum value found between the amount of the investor's risk and capital transactions. Model of optimal placement of funds led to the conclusion about inexpediency strong increase in the diversification of the investment portfolio (more than 10 different types of assets in the portfolio, since it increases the complexity of its practical form, while the portfolio characteristics are improved significantly. It is concluded that it is impossible to increase revenue without increasing the risk or reduce risk without reducing income. The analysis shows that there is no single best asset portfolio. It is impossible to increase revenue without increasing the risk or reduce risk without reducing income. Possible combination of the "riskincome" will depend on the objective function. Most diversified and bringing the best return per unit of risk, is a portfolio that contains the most risky assets.
Institute of Scientific and Technical Information of China (English)
魏生贤; 胡粉娥; 晏翠琼
2016-01-01
thermal performance of the flat-plate type solar energy water heater has been studied globally. In order to ensure the efficient operation of the solar water heater and user's demand to the terminal temperature of a tank, the countries all over the world with different climate have given different recommended value for water-mass-to-collector-area ratio (the ratio is abbreviated as MAR) of the flat-plate solar water heater. However, China has a vast territory and its climate is complex. The value range of recommended value from literatures is too large to be used to practical application. The main residential buildings in large and medium-sized cities are mostly high-rise buildings. The solar water heater installed on roof can only meet hot water use for the top six to eight floors. The application of the balcony wall-mounted solar water heater is one of the effective ways to solve hot water needs for the rest of users in high-rise buildings. Based on the typical meteorological data of nine cities in mild region of China, the values of MAR of the balcony wall-mounted flat-plate solar water heater have been calculated by using the established mathematical model. The water tank terminal temperature of 60℃, the collector angle of 60°-90° and the azimuth angle of 0-90° were used in model analysis. Calculation results for south-facing balcony wall-mounted solar water heater in mild region showed that the appropriate MAR of spring, summer, autumn, winter and the whole year was 28-51, 21-41, 31-53, 37-57 and 31-47 kg/m2, respectively. For convenience of practical application, the linear regression relation between seasonal and annual average MAR and the tilt angle for south-facing balcony wall-mounted solar water heater. The correlation coefficients between them were greater than 0.99. In this paper, we introduced a new concept “azimuth factor of MAR” which was easy to calculate MAR for the collector with different azimuth angle. For the non-south-facing balcony wall
Corporate prediction models, ratios or regression analysis?
Bijnen, E.J.; Wijn, M.F.C.M.
1994-01-01
The models developed in the literature with respect to the prediction of a company s failure are based on ratios. It has been shown before that these models should be rejected on theoretical grounds. Our study of industrial companies in the Netherlands shows that the ratios which are used in
CCSSM Challenge: Graphing Ratio and Proportion
Kastberg, Signe E.; D'Ambrosio, Beatriz S.; Lynch-Davis, Kathleen; Mintos, Alexia; Krawczyk, Kathryn
2013-01-01
A renewed emphasis was placed on ratio and proportional reasoning in the middle grades in the Common Core State Standards for Mathematics (CCSSM). The expectation for students includes the ability to not only compute and then compare and interpret the results of computations in context but also interpret ratios and proportions as they are…
Osmosis and Surface Area to Volume Ratio.
Barrett, D. R. B.
1984-01-01
Describes an experiment designed to help students understand the concepts of osmosis and surface area to volume ratio (SA:VOL). The task for students is to compare water uptake in different sizes of potato cubes and relate differences to their SA:VOL ratios. (JN)
Key financial ratios can foretell hospital closures.
Lynn, M L; Wertheim, P
1993-11-01
An analysis of various financial ratios sampled from open and closed hospitals shows that certain leverage, liquidity, capital efficiency, and resource availability ratios can predict hospital closure up to two years in advance of the closure with an accuracy of nearly 75 percent.
How to use and interpret hormone ratios.
Sollberger, Silja; Ehlert, Ulrike
2016-01-01
Hormone ratios have become increasingly popular throughout the neuroendocrine literature since they offer a straightforward way to simultaneously analyze the effects of two interdependent hormones. However, the analysis of ratios is associated with statistical and interpretational concerns which have not been sufficiently considered in the context of endocrine research. The aim of this article, therefore, is to demonstrate and discuss these issues, and to suggest suitable ways to address them. In a first step, we use exemplary testosterone and cortisol data to illustrate that one major concern of ratios lies in their distribution and inherent asymmetry. As a consequence, results of parametric statistical analyses are affected by the ultimately arbitrary decision of which way around the ratio is computed (i.e., A/B or B/A). We suggest the use of non-parametric methods as well as the log-transformation of hormone ratios as appropriate methods to deal with these statistical problems. However, in a second step, we also discuss the complicated interpretation of ratios, and propose moderation analysis as an alternative and oftentimes more insightful approach to ratio analysis. In conclusion, we suggest that researchers carefully consider which statistical approach is best suited to investigate reciprocal hormone effects. With regard to the hormone ratio method, further research is needed to specify what exactly this index reflects on the biological level and in which cases it is a meaningful variable to analyze.
The Divine Ratio and Golden Rectangles.
Cooper, Martin
1982-01-01
The material examines aspects of Fibonacci and Lucas sequences, the generation of the Divine Ratio, and the nature of this ratio in golden rectangles, triangles, and figures made up of golden triangles. It is noted Lucas sequence is formed like Fibonacci but has one and three as the first elements. (Author/MP)
Design of flying vehicle control system by signal to noise ratio
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Presents the new concept of ″Desired to be small″ based on thebasic function of vehicle flight control system for an optimal design of flying vehicle control system, and the definition of S/N ratio and calculation formula for ″Desired to be small″ dynamic characteristics, and the S/N ratio method established for design of velicle flight control systems, by which, an orthogrnal table is used to arrange test schemes, and error facters are used to simulate various interferences, and the use of S/N ratio as a design criterion to synthesise the design of dynamic and static characteristics for definition of an optimal scheme, the application of S/N ratio method to the design of a type of vehicle control system and the single run success abtained in design of control system, technical evaluation test and design finalization flight test.
Duty ratio of cooperative molecular motors.
Dharan, Nadiv; Farago, Oded
2012-02-01
Molecular motors are found throughout the cells of the human body and have many different and important roles. These micromachines move along filament tracks and have the ability to convert chemical energy into mechanical work that powers cellular motility. Different types of motors are characterized by different duty ratios, which is the fraction of time that a motor is attached to its filament. In the case of myosin II (a nonprocessive molecular machine with a low duty ratio), cooperativity between several motors is essential to induce motion along its actin filament track. In this work we use statistical mechanical tools to calculate the duty ratio of cooperative molecular motors. The model suggests that the effective duty ratio of nonprocessive motors that work in cooperation is lower than the duty ratio of the individual motors. The origin of this effect is the elastic tension that develops in the filament which is relieved when motors detach from the track.
Equity Theory Ratios as Causal Schemas
Directory of Open Access Journals (Sweden)
Alexios Arvanitis
2016-08-01
Full Text Available Equity theory approaches justice evaluations based on ratios of exchange inputs to exchange outcomes. Situations are evaluated as just if ratios are equal and unjust if unequal. We suggest that equity ratios serve a more fundamental cognitive function than the evaluation of justice. More particularly, we propose that they serve as causal schemas for exchange outcomes, that is, they assist in determining whether certain outcomes are caused by inputs of other people in the context of an exchange process. Equality or inequality of ratios in this sense points to an exchange process. Indeed, Study 1 shows that different exchange situations, such as disproportional or balanced proportional situations, create perceptions of give-and-take on the basis of equity ratios. Study 2 shows that perceptions of justice are based more on communicatively accepted rules of interaction than equity-based evaluations, thereby offering a distinction between an attribution and an evaluation cognitive process for exchange outcomes.
Hydrodynamic chromatography and field flow fractionation in finite aspect ratio channels.
Shendruk, T N; Slater, G W
2014-04-25
Hydrodynamic chromatography (HC) and field-flow fractionation (FFF) separation methods are often performed in 3D rectangular channels, though ideal retention theory assumes 2D systems. Devices are commonly designed with large aspect ratios; however, it can be unavoidable or desirable to design rectangular channels with small or even near-unity aspect ratios. To assess the significance of finite-aspect ratio effects and interpret experimental retention results, an ideal, analytical retention theory is needed. We derive a series solution for the ideal retention ratio of HC and FFF rectangular channels. Rather than limiting devices' ability to resolve samples, our theory predicts that retention curves for normal-mode FFF are well approximated by the infinite plate solution and that the performance of HC is actually improved. These findings suggest that FFF devices need not be designed with large aspect ratios and that rectangular HC channels are optimal when the aspect ratio is unity.
Applications of combinatorial optimization
Paschos, Vangelis Th
2013-01-01
Combinatorial optimization is a multidisciplinary scientific area, lying in the interface of three major scientific domains: mathematics, theoretical computer science and management. The three volumes of the Combinatorial Optimization series aims to cover a wide range of topics in this area. These topics also deal with fundamental notions and approaches as with several classical applications of combinatorial optimization. "Applications of Combinatorial Optimization" is presenting a certain number among the most common and well-known applications of Combinatorial Optimization.
New Hoopoe Heuristic Optimization
El-Dosuky, Mohammed; EL-Bassiouny, Ahmed; Hamza, Taher; Rashad, Magdy
2012-01-01
Most optimization problems in real life applications are often highly nonlinear. Local optimization algorithms do not give the desired performance. So, only global optimization algorithms should be used to obtain optimal solutions. This paper introduces a new nature-inspired metaheuristic optimization algorithm, called Hoopoe Heuristic (HH). In this paper, we will study HH and validate it against some test functions. Investigations show that it is very promising and could be seen as an optimi...
Optimal online bounded space multidimensional packing
L. Epstein (Lea); R. van Stee (Rob)
2003-01-01
textabstractWe solve an open problem in the literature by providing an online algorithm for multidimensional bin packing that uses only bounded space. We show that it is optimal among bounded space algorithms for any dimension $d>1$. Its asymptotic performance ratio is $(Pi_{infty})^d$, where
LTE-Advanced Radio and Network Optimization
DEFF Research Database (Denmark)
Velez, Fernando J.; Sousa, Sofia; Flores, Jessica Acevedo
2017-01-01
In cellular optimization, the UL and DL the values from carrier-to-noise-plus-interference ratio (CNIR) from/at the mobile station are very important parameters. From a detailed analysis of its variation with the coverage and reuse distances for different values of the Channel Quality Indicator (...
CALIPSO lidar ratio retrieval over the ocean.
Josset, Damien; Rogers, Raymond; Pelon, Jacques; Hu, Yongxiang; Liu, Zhaoyan; Omar, Ali; Zhai, Peng-Wang
2011-09-12
We are demonstrating on a few cases the capability of CALIPSO to retrieve the 532 nm lidar ratio over the ocean when CloudSat surface scattering cross section is used as a constraint. We are presenting the algorithm used and comparisons with the column lidar ratio retrieved by the NASA airborne high spectral resolution lidar. For the three cases presented here, the agreement is fairly good. The average CALIPSO 532 nm column lidar ratio bias is 13.7% relative to HSRL, and the relative standard deviation is 13.6%. Considering the natural variability of aerosol microphysical properties, this level of accuracy is significant since the lidar ratio is a good indicator of aerosol types. We are discussing dependencies of the accuracy of retrieved aerosol lidar ratio on atmospheric aerosol homogeneity, lidar signal to noise ratio, and errors in the optical depth retrievals. We are obtaining the best result (bias 7% and standard deviation around 6%) for a nighttime case with a relatively constant lidar ratio (in the vertical) indicative of homogeneous aerosol type.
Selecting the aspect ratio of a scatter plot based on its delaunay triangulation.
Fink, Martin; Haunert, Jan-Henrik; Spoerhase, Joachim; Wolff, Alexander
2013-12-01
Scatter plots are diagrams that visualize two-dimensional data as sets of points in the plane. They allow users to detect correlations and clusters in the data. Whether or not a user can accomplish these tasks highly depends on the aspect ratio selected for the plot, i.e., the ratio between the horizontal and the vertical extent of the diagram. We argue that an aspect ratio is good if the Delaunay triangulation of the scatter plot at this aspect ratio has some nice geometric property, e.g., a large minimum angle or a small total edge length. More precisely, we consider the following optimization problem. Given a set Q of points in the plane, find a scale factor s such that scaling the x-coordinates of the points in Q by s and the y-coordinates by 1=s yields a point set P(s) that optimizes a property of the Delaunay triangulation of P(s), over all choices of s. We present an algorithm that solves this problem efficiently and demonstrate its usefulness on real-world instances. Moreover, we discuss an empirical test in which we asked 64 participants to choose the aspect ratios of 18 scatter plots. We tested six different quality measures that our algorithm can optimize. In conclusion, minimizing the total edge length and minimizing what we call the 'uncompactness' of the triangles of the Delaunay triangulation yielded the aspect ratios that were most similar to those chosen by the participants in the test.
Optimally moderated nuclear fission reactor and fuel source therefor
Ougouag, Abderrafi M.; Terry, William K.; Gougar, Hans D.
2008-07-22
An improved nuclear fission reactor of the continuous fueling type involves determining an asymptotic equilibrium state for the nuclear fission reactor and providing the reactor with a moderator-to-fuel ratio that is optimally moderated for the asymptotic equilibrium state of the nuclear fission reactor; the fuel-to-moderator ratio allowing the nuclear fission reactor to be substantially continuously operated in an optimally moderated state.
Introducing optional reserve ratios in Hungary
Lóránt Varga
2010-01-01
As of the reserve maintenance period commencing in November 2010, Hungarian credit institutions will be free to decide whether to apply the previously valid 2% reserve ratio, or to apply a higher mandatory reserve ratio. Credit institutions required to hold reserves may select from reserve ratios of 2, 3, 4 and 5%, and may change their decision on a semi-annual basis. In line with the international best practice, the purpose of the MNB’s reserve requirement system is to support credit institu...
Financial Ratios and Perceived Household Financial Satisfaction
Directory of Open Access Journals (Sweden)
Scott Garrett
2013-08-01
Full Text Available This paper tests the relative strength of three objective measures of financial health (using the solvency, liquidity, and investment asset ratio in predicting a household’s subjective feeling of current financial satisfaction. Using a sample of 6,923 respondents in the 2008 Health and Retirement Study this paper presents evidence of two main findings: 1 the solvency ratio is most strongly associated with financial satisfaction levels based on a cross-sectional design and 2 changes in the investment asset ratio are most strongly associated with changes in financial satisfaction over time.
Corriveau, F.; Hasinoff, M. D.; Measday, D. F.; Poutissou, J.-M.; Salomon, M.
1987-11-01
The branching ratios have been measured for γ-ray channels produced by π- stopping in liquid 3He. The results for the Panofsky ratio are P3 = ω( π-3He → π0t)/ ω( π-3He → γt) = 2.83 ± 0.07, and for the ratio of the radiative breakup channels, B3 = ω)( π-3He → γnd + γnnp)/ ω( π-3He → γt) = 1.35 ±0.11.
Mechanical Design Optimization Using Advanced Optimization Techniques
Rao, R Venkata
2012-01-01
Mechanical design includes an optimization process in which designers always consider objectives such as strength, deflection, weight, wear, corrosion, etc. depending on the requirements. However, design optimization for a complete mechanical assembly leads to a complicated objective function with a large number of design variables. It is a good practice to apply optimization techniques for individual components or intermediate assemblies than a complete assembly. Analytical or numerical methods for calculating the extreme values of a function may perform well in many practical cases, but may fail in more complex design situations. In real design problems, the number of design parameters can be very large and their influence on the value to be optimized (the goal function) can be very complicated, having nonlinear character. In these complex cases, advanced optimization algorithms offer solutions to the problems, because they find a solution near to the global optimum within reasonable time and computational ...
Benchmarking optimization solvers for structural topology optimization
DEFF Research Database (Denmark)
Rojas Labanda, Susana; Stolpe, Mathias
2015-01-01
The purpose of this article is to benchmark different optimization solvers when applied to various finite element based structural topology optimization problems. An extensive and representative library of minimum compliance, minimum volume, and mechanism design problem instances for different...... sizes is developed for this benchmarking. The problems are based on a material interpolation scheme combined with a density filter. Different optimization solvers including Optimality Criteria (OC), the Method of Moving Asymptotes (MMA) and its globally convergent version GCMMA, the interior point...... profiles conclude that general solvers are as efficient and reliable as classical structural topology optimization solvers. Moreover, the use of the exact Hessians in SAND formulations, generally produce designs with better objective function values. However, with the benchmarked implementations solving...
Microgenetic optimization algorithm for optimal wavefront shaping
Anderson, Benjamin R; Gunawidjaja, Ray; Eilers, Hergen
2015-01-01
One of the main limitations of utilizing optimal wavefront shaping in imaging and authentication applications is the slow speed of the optimization algorithms currently being used. To address this problem we develop a micro-genetic optimization algorithm ($\\mu$GA) for optimal wavefront shaping. We test the abilities of the $\\mu$GA and make comparisons to previous algorithms (iterative and simple-genetic) by using each algorithm to optimize transmission through an opaque medium. From our experiments we find that the $\\mu$GA is faster than both the iterative and simple-genetic algorithms and that both genetic algorithms are more resistant to noise and sample decoherence than the iterative algorithm.
Particle Swarm Optimization Toolbox
Grant, Michael J.
2010-01-01
The Particle Swarm Optimization Toolbox is a library of evolutionary optimization tools developed in the MATLAB environment. The algorithms contained in the library include a genetic algorithm (GA), a single-objective particle swarm optimizer (SOPSO), and a multi-objective particle swarm optimizer (MOPSO). Development focused on both the SOPSO and MOPSO. A GA was included mainly for comparison purposes, and the particle swarm optimizers appeared to perform better for a wide variety of optimization problems. All algorithms are capable of performing unconstrained and constrained optimization. The particle swarm optimizers are capable of performing single and multi-objective optimization. The SOPSO and MOPSO algorithms are based on swarming theory and bird-flocking patterns to search the trade space for the optimal solution or optimal trade in competing objectives. The MOPSO generates Pareto fronts for objectives that are in competition. A GA, based on Darwin evolutionary theory, is also included in the library. The GA consists of individuals that form a population in the design space. The population mates to form offspring at new locations in the design space. These offspring contain traits from both of the parents. The algorithm is based on this combination of traits from parents to hopefully provide an improved solution than either of the original parents. As the algorithm progresses, individuals that hold these optimal traits will emerge as the optimal solutions. Due to the generic design of all optimization algorithms, each algorithm interfaces with a user-supplied objective function. This function serves as a "black-box" to the optimizers in which the only purpose of this function is to evaluate solutions provided by the optimizers. Hence, the user-supplied function can be numerical simulations, analytical functions, etc., since the specific detail of this function is of no concern to the optimizer. These algorithms were originally developed to support entry
Optimization of composite laminates
Gurdal, Zafer; Haftka, Raphael T.
Design of composite structures can be viewed as a multi-faceted task, one which requires integration of issues related to composite mechanics, structural analysis, optimization, and manufacturing. The major coverage of the paper is on the issue of optimization, with special emphasis on the use of optimization for designing with discrete and integer valued variables required for the stacking-sequence optimization. Different techniques that can be used for stacking sequence optimization are introduced, and different aspects of their application are demonstrated for laminate buckling optimization.
Asthma Medication Ratio Predicts Emergency Depart...
U.S. Department of Health & Human Services — According to findings reported in Asthma Medication Ratio Predicts Emergency Department Visits and Hospitalizations in Children with Asthma, published in Volume 3,...
Negative Poisson's Ratio in Modern Functional Materials.
Huang, Chuanwei; Chen, Lang
2016-10-01
Materials with negative Poisson's ratio attract considerable attention due to their underlying intriguing physical properties and numerous promising applications, particularly in stringent environments such as aerospace and defense areas, because of their unconventional mechanical enhancements. Recent progress in materials with a negative Poisson's ratio are reviewed here, with the current state of research regarding both theory and experiment. The inter-relationship between the underlying structure and a negative Poisson's ratio is discussed in functional materials, including macroscopic bulk, low-dimensional nanoscale particles, films, sheets, or tubes. The coexistence and correlations with other negative indexes (such as negative compressibility and negative thermal expansion) are also addressed. Finally, open questions and future research opportunities are proposed for functional materials with negative Poisson's ratios.
Determining sex ratios of turtle hatchlings
National Oceanic and Atmospheric Administration, Department of Commerce — Previous status assessments of marine turtles have assumed that the natural sex ratio of a marine turtle population is 1:1 (e.g. Conant et al. 2009). However, this...
Institute of Scientific and Technical Information of China (English)
无
2004-01-01
The demographic structure of populations,particularly age and sex, has profound consequences for harmonious and sustainable social and economic development. Furthermore, analyzing sex ratios of populations is important in analyzing the development of the status Of women and girls.
Ratio Analysis: Where Investments Meet Mathematics.
Barton, Susan D.; Woodbury, Denise
2002-01-01
Discusses ratio analysis by which investments may be evaluated. Requires the use of fundamental mathematics, problem solving, and a comparison of the mathematical results within the framework of industry. (Author/NB)
Enantiomer fractions instead of enantiomer ratios
Geus, de H.J.; Wester, P.G.; Boer, de J.; Brinkman, U.A.Th.
2000-01-01
The use of enantiomer ratios (ERs) to indicate the relative amounts of a pair of enantiomers in a sample has some disadvantages. Enantiomer fractions (EFs) are proposed as all alternative expression to eliminate the difficulties. (C) 2000 Elsevier Science Ltd.
From Fibonacci Sequence to the Golden Ratio
Directory of Open Access Journals (Sweden)
Alberto Fiorenza
2013-01-01
Full Text Available We consider the well-known characterization of the Golden ratio as limit of the ratio of consecutive terms of the Fibonacci sequence, and we give an explanation of this property in the framework of the Difference Equations Theory. We show that the Golden ratio coincides with this limit not because it is the root with maximum modulus and multiplicity of the characteristic polynomial, but, from a more general point of view, because it is the root with maximum modulus and multiplicity of a restricted set of roots, which in this special case coincides with the two roots of the characteristic polynomial. This new perspective is the heart of the characterization of the limit of ratio of consecutive terms of all linear homogeneous recurrences with constant coefficients, without any assumption on the roots of the characteristic polynomial, which may be, in particular, also complex and not real.
Optimality in Data Assimilation
Nearing, Grey; Yatheendradas, Soni
2016-04-01
It costs a lot more to develop and launch an earth-observing satellite than it does to build a data assimilation system. As such, we propose that it is important to understand the efficiency of our assimilation algorithms at extracting information from remote sensing retrievals. To address this, we propose that it is necessary to adopt completely general definition of "optimality" that explicitly acknowledges all differences between the parametric constraints of our assimilation algorithm (e.g., Gaussianity, partial linearity, Markovian updates) and the true nature of the environmetnal system and observing system. In fact, it is not only possible, but incredibly straightforward, to measure the optimality (in this more general sense) of any data assimilation algorithm as applied to any intended model or natural system. We measure the information content of remote sensing data conditional on the fact that we are already running a model and then measure the actual information extracted by data assimilation. The ratio of the two is an efficiency metric, and optimality is defined as occurring when the data assimilation algorithm is perfectly efficient at extracting information from the retrievals. We measure the information content of the remote sensing data in a way that, unlike triple collocation, does not rely on any a priori presumed relationship (e.g., linear) between the retrieval and the ground truth, however, like triple-collocation, is insensitive to the spatial mismatch between point-based measurements and grid-scale retrievals. This theory and method is therefore suitable for use with both dense and sparse validation networks. Additionally, the method we propose is *constructive* in the sense that it provides guidance on how to improve data assimilation systems. All data assimilation strategies can be reduced to approximations of Bayes' law, and we measure the fractions of total information loss that are due to individual assumptions or approximations in the
Mills' ratio: Reciprocal concavity and functional inequalities
Baricz, Árpád
2010-01-01
This note contains suficient conditions for the probability density function of an arbitrary continuous univariate distribution such that the corresponding Mills ratio to be reciprocally convex (concave). To illustrate the applications of the main results, the Mills ratio of some common continuous univariate distributions, like gamma, log-normal and Student's t distributions, are discussed in details. The application to monopoly theory is also summarized.
$\\tau$ hadronic branching ratios at DELPHI
Humble, Stephen
1999-01-01
Using data collected in the DELPHI detector at LEP1, we have measured the exclusive branching ratios in modes with several hadrons. Both classical cuts and neural network methods have been performed to make the best use of the DELPHI neutral particle identification capability. In addition, a measurement of inclusive branching ratios for tau decays containing one or three charged particles has been performed. (4 refs).
The Laplace Likelihood Ratio Test for Heteroscedasticity
Directory of Open Access Journals (Sweden)
J. Martin van Zyl
2011-01-01
Full Text Available It is shown that the likelihood ratio test for heteroscedasticity, assuming the Laplace distribution, gives good results for Gaussian and fat-tailed data. The likelihood ratio test, assuming normality, is very sensitive to any deviation from normality, especially when the observations are from a distribution with fat tails. Such a likelihood test can also be used as a robust test for a constant variance in residuals or a time series if the data is partitioned into groups.
Golden Ratio: A Measure of Physical Beauty
Indian Academy of Sciences (India)
2017-01-01
Our attraction to another body increases if the body is symmetricaland in proportion. If a face or a structure is in proportion,we are more likely to notice it and find it beautiful.The universal ratio of beauty is the ‘Golden Ratio’, found inmany structures. This ratio comes from Fibonacci numbers.In this article, we explore this concept along with its applications.
Multi-objective optimization of an axial compressor blade
Energy Technology Data Exchange (ETDEWEB)
Samad, Abdus; Kim, Kwang Yong [Inha University, Incheon (Korea, Republic of)
2008-05-15
Numerical optimization with multiple objectives is carried out for design of an axial compressor blade. Two conflicting objectives, total pressure ratio and adiabatic efficiency, are optimized with three design variables concerning sweep, lean and skew of blade stacking line. Single objective optimizations have been also performed. At the data points generated by D-optimal design, the objectives are calculated by three-dimensional Reynolds-averaged Navier-Stokes analysis. A second-order polynomial based response surface model is generated, and the optimal point is searched by sequential quadratic programming method for single objective optimization. Elitist non-dominated sorting of genetic algorithm (NSGA-II) with {epsilon}-constraint local search strategy is used for multi-objective optimization. Both objective function values are found to be improved as compared to the reference one by multi-objective optimization. The flow analysis results show the mechanism for the improvement of blade performance
Spectral variability of the particulate backscattering ratio
Whitmire, A. L.; Boss, E.; Cowles, T. J.; Pegau, W. S.
2007-05-01
The spectral dependency of the particulate backscattering ratio is relevant in the fields of ocean color inversion, light field modeling, and inferring particle properties from optical measurements. Aside from theoretical predictions for spherical, homogeneous particles, we have very limited knowledge of the actual in situ spectral variability of the particulate backscattering ratio. This work presents results from five research cruises that were conducted over a three-year period. Water column profiles of physical and optical properties were conducted across diverse aquatic environments that offered a wide range of particle populations. The main objective of this research was to examine the behavior of the spectral particulate backscattering ratio in situ, both in terms of its absolute magnitude and its variability across visible wavelengths, using over nine thousand 1-meter binned data points for each of five wavelengths of the spectral particulate backscattering ratio. Our analysis reveals no spectral dependence of the particulate backscattering ratio within our measurement certainty, and a geometric mean value of 0.013 for this dataset. This is lower than the commonly used value of 0.0183 from Petzold’s integrated volume scattering data. Within the first optical depth of the water column, the mean particulate backscattering ratio was 0.010.
Plutonium isotope ratio variations in North America
Energy Technology Data Exchange (ETDEWEB)
Steiner, Robert E [Los Alamos National Laboratory; La Mont, Stephen P [Los Alamos National Laboratory; Eisele, William F [Los Alamos National Laboratory; Fresquez, Philip R [Los Alamos National Laboratory; Mc Naughton, Michael [Los Alamos National Laboratory; Whicker, Jeffrey J [Los Alamos National Laboratory
2010-12-14
Historically, approximately 12,000 TBq of plutonium was distributed throughout the global biosphere by thermo nuclear weapons testing. The resultant global plutonium fallout is a complex mixture whose {sup 240}Pu/{sup 239}Pu atom ratio is a function of the design and yield of the devices tested. The average {sup 240}Pu/{sup 239}Pu atom ratio in global fallout is 0.176 + 014. However, the {sup 240}Pu/{sup 239}Pu atom ratio at any location may differ significantly from 0.176. Plutonium has also been released by discharges and accidents associated with the commercial and weapons related nuclear industries. At many locations contributions from this plutonium significantly alters the {sup 240}Pu/{sup 239}Pu atom ratios from those observed in global fallout. We have measured the {sup 240}Pu/{sup 239}Pu atom ratios in environmental samples collected from many locations in North America. This presentation will summarize the analytical results from these measurements. Special emphasis will be placed on interpretation of the significance of the {sup 240}Pu/{sup 239}Pu atom ratios measured in environmental samples collected in the Arctic and in the western portions of the United States.
A note on trader Sharpe Ratios.
Directory of Open Access Journals (Sweden)
John M Coates
Full Text Available Traders in the financial world are assessed by the amount of money they make and, increasingly, by the amount of money they make per unit of risk taken, a measure known as the Sharpe Ratio. Little is known about the average Sharpe Ratio among traders, but the Efficient Market Hypothesis suggests that traders, like asset managers, should not outperform the broad market. Here we report the findings of a study conducted in the City of London which shows that a population of experienced traders attain Sharpe Ratios significantly higher than the broad market. To explain this anomaly we examine a surrogate marker of prenatal androgen exposure, the second-to-fourth finger length ratio (2D:4D, which has previously been identified as predicting a trader's long term profitability. We find that it predicts the amount of risk taken by traders but not their Sharpe Ratios. We do, however, find that the traders' Sharpe Ratios increase markedly with the number of years they have traded, a result suggesting that learning plays a role in increasing the returns of traders. Our findings present anomalous data for the Efficient Markets Hypothesis.
A note on trader Sharpe Ratios.
Coates, John M; Page, Lionel
2009-11-25
Traders in the financial world are assessed by the amount of money they make and, increasingly, by the amount of money they make per unit of risk taken, a measure known as the Sharpe Ratio. Little is known about the average Sharpe Ratio among traders, but the Efficient Market Hypothesis suggests that traders, like asset managers, should not outperform the broad market. Here we report the findings of a study conducted in the City of London which shows that a population of experienced traders attain Sharpe Ratios significantly higher than the broad market. To explain this anomaly we examine a surrogate marker of prenatal androgen exposure, the second-to-fourth finger length ratio (2D:4D), which has previously been identified as predicting a trader's long term profitability. We find that it predicts the amount of risk taken by traders but not their Sharpe Ratios. We do, however, find that the traders' Sharpe Ratios increase markedly with the number of years they have traded, a result suggesting that learning plays a role in increasing the returns of traders. Our findings present anomalous data for the Efficient Markets Hypothesis.
Technique for Selecting Optimum Fan Compression Ratio based on the Effective Power Plant Parameters
Directory of Open Access Journals (Sweden)
I. I. Kondrashov
2016-01-01
Full Text Available Nowadays, civilian aircrafts occupy the major share of global aviation industry market. As to medium and long - haul aircrafts, turbofans with separate exhaust streams are widely used. Here, fuel efficiency is the main criterion of this engine. The paper presents the research results of the mutual influence of fan pressure ratio and bypass ratio on the effective specific fuel consumption. Shows the increasing bypass ratio to be a rational step for reducing the fuel consumption. Also considers the basic features of engines with a high bypass ratio. Among the other working process parameters, fan pressure ratio and bypass ratio are the most relevant for consideration as they are the most structural variables at a given level of technical excellence. The paper presents the dependence of the nacelle drag coefficient on the engine bypass ratio. For computation were adopted the projected parameters of prospective turbofans to be used in the power plant of the 180-seat medium-haul aircraft. Computation of the engine cycle was performed in Mathcad using these data, with fan pressure ratio and bypass ratio being varied. The combustion chamber gas temperature, the overall pressure ratio and engine thrust remained constant. Pressure loss coefficients, the efficiency of the engine components and the amount of air taken for cooling also remained constant. The optimal parameters corresponding to the minimum effective specific fuel consumption were found as the result of computation. The paper gives recommendations for adjusting optimal parameters, depending on the considered external factors, such as weight of engine and required fuel reserve. The obtained data can be used to estimate parameters of future turbofan engines with high bypass ratio.
Application of alternative anthropometric measurements to predict metabolic syndrome
Directory of Open Access Journals (Sweden)
Gul Sagun
2014-01-01
Full Text Available OBJECTIVE: The association between rarely used anthropometric measurements (e.g., mid-upper arm, forearm, and calf circumference and metabolic syndrome has not been proven. The aim of this study was to assess whether mid-upper arm, forearm, calf, and waist circumferences, as well as waist/height ratio and waist-to-hip ratio, were associated with metabolic syndrome. METHODS: We enrolled 387 subjects (340 women, 47 men who were admitted to the obesity outpatient department of Istanbul Medeniyet University Goztepe Training and Research Hospital between September 2010 and December 2010. The following measurements were recorded: waist circumference, hip circumference, waist/height ratio, waist-to-hip ratio, mid-upper arm circumference, forearm circumference, calf circumference, and body composition. Fasting blood samples were collected to measure plasma glucose, lipids, uric acid, insulin, and HbA1c. RESULTS: The odds ratios for visceral fat (measured via bioelectric impedance, hip circumference, forearm circumference, and waist circumference/hip circumference were 2.19 (95% CI, 1.30-3.71, 1.89 (95% CI, 1.07-3.35, 2.47 (95% CI, 1.24-4.95, and 2.11(95% CI, 1.26-3.53, respectively. The bioelectric impedance-measured body fat percentage correlated with waist circumference only in subjects without metabolic syndrome; the body fat percentage was negatively correlated with waist circumference/hip circumference in the metabolic syndrome group. All measurements except for forearm circumference were equally well correlated with the bioelectric impedance-measured body fat percentages in both groups. Hip circumference was moderately correlated with bioelectric impedance-measured visceral fat in subjects without metabolic syndrome. Muscle mass (measured via bioelectric impedance was weakly correlated with waist and forearm circumference in subjects with metabolic syndrome and with calf circumference in subjects without metabolic syndrome. CONCLUSION: Waist
Oil Reservoir Production Optimization using Optimal Control
DEFF Research Database (Denmark)
Völcker, Carsten; Jørgensen, John Bagterp; Stenby, Erling Halfdan
2011-01-01
Practical oil reservoir management involves solution of large-scale constrained optimal control problems. In this paper we present a numerical method for solution of large-scale constrained optimal control problems. The method is a single-shooting method that computes the gradients using the adjo......Practical oil reservoir management involves solution of large-scale constrained optimal control problems. In this paper we present a numerical method for solution of large-scale constrained optimal control problems. The method is a single-shooting method that computes the gradients using...... the adjoint method. We use an Explicit Singly Diagonally Implicit Runge-Kutta (ESDIRK) method for the integration and a quasi-Newton Sequential Quadratic Programming (SQP) algorithm for the constrained optimization. We use this algorithm in a numerical case study to optimize the production of oil from an oil...... reservoir using water ooding and smart well technology. Compared to the uncontrolled case, the optimal operation increases the Net Present Value of the oil field by 10%....
Optimization with PDE constraints
Pinnau, Rene
2008-01-01
Presents an introduction of pde constrained optimization. This book provides a precise functional analytic treatment via optimality conditions and a non-smooth algorithmical framework. It also presents structure-exploiting discrete concepts and large scale, practically relevant applications.
National Aeronautics and Space Administration — An optimal alarm system is simply an optimal level-crossing predictor that can be designed to elicit the fewest false alarms for a fixed detection probability. It...
Directory of Open Access Journals (Sweden)
Deepak Goyal
2013-07-01
Full Text Available This paper addresses the malicious node detection and path optimization problem for wireless sensor networks. Malicious node detection in neighborhood is a needed because that node may cause incorrect decisions or energy depletion. In this paper APSO (combination of Artificial bee colony and particular swarm optimization is used to choose an optimized path. Through this improved version we will overcome the disadvantage of local optimal which comes when we use PSO approach.
Optimization techniques in statistics
Rustagi, Jagdish S
1994-01-01
Statistics help guide us to optimal decisions under uncertainty. A large variety of statistical problems are essentially solutions to optimization problems. The mathematical techniques of optimization are fundamentalto statistical theory and practice. In this book, Jagdish Rustagi provides full-spectrum coverage of these methods, ranging from classical optimization and Lagrange multipliers, to numerical techniques using gradients or direct search, to linear, nonlinear, and dynamic programming using the Kuhn-Tucker conditions or the Pontryagin maximal principle. Variational methods and optimiza
Pseudolinear functions and optimization
Mishra, Shashi Kant
2015-01-01
Pseudolinear Functions and Optimization is the first book to focus exclusively on pseudolinear functions, a class of generalized convex functions. It discusses the properties, characterizations, and applications of pseudolinear functions in nonlinear optimization problems.The book describes the characterizations of solution sets of various optimization problems. It examines multiobjective pseudolinear, multiobjective fractional pseudolinear, static minmax pseudolinear, and static minmax fractional pseudolinear optimization problems and their results. The authors extend these results to locally
Optimization algorithms and applications
Arora, Rajesh Kumar
2015-01-01
Choose the Correct Solution Method for Your Optimization ProblemOptimization: Algorithms and Applications presents a variety of solution techniques for optimization problems, emphasizing concepts rather than rigorous mathematical details and proofs. The book covers both gradient and stochastic methods as solution techniques for unconstrained and constrained optimization problems. It discusses the conjugate gradient method, Broyden-Fletcher-Goldfarb-Shanno algorithm, Powell method, penalty function, augmented Lagrange multiplier method, sequential quadratic programming, method of feasible direc
Sex ratios at birth after induced abortion.
Urquia, Marcelo L; Moineddin, Rahim; Jha, Prabhat; O'Campo, Patricia J; McKenzie, Kwame; Glazier, Richard H; Henry, David A; Ray, Joel G
2016-06-14
Skewed male:female ratios at birth have been observed among certain immigrant groups. Data on abortion practices that might help to explain these findings are lacking. We examined 1 220 933 births to women with up to 3 consecutive singleton live births between 1993 and 2012 in Ontario. Records of live births, and induced and spontaneous abortions were linked to Canadian immigration records. We determined associations of male:female infant ratios with maternal birthplace, sex of the previous living sibling(s) and prior spontaneous or induced abortions. Male:female infant ratios did not appreciably depart from the normal range among Canadian-born women and most women born outside of Canada, irrespective of the sex of previous children or the characteristics of prior abortions. However, among infants of women who immigrated from India and had previously given birth to 2 girls, the overall male:female ratio was 1.96 (95% confidence interval [CI] 1.75-2.21) for the third live birth. The male:female infant ratio after 2 girls was 1.77 (95% CI 1.26-2.47) times higher if the current birth was preceded by 1 induced abortion, 2.38 (95% CI 1.44-3.94) times higher if preceded by 2 or more induced abortions and 3.88 (95% CI 2.02-7.50) times higher if the induced abortion was performed at 15 weeks or more gestation relative to no preceding abortion. Spontaneous abortions were not associated with male-biased sex ratios in subsequent births. High male:female ratios observed among infants born to women who immigrated from India are associated with induced abortions, especially in the second trimester of pregnancy. © 2016 Canadian Medical Association or its licensors.
Energy Technology Data Exchange (ETDEWEB)
Jurdziak, L.
1992-08-01
Discusses the basic financial ratios used to assess the financial standing of a mining enterprise: liquidity, leverage/gearing, activity and profitability ratios, cash flow to the current portion of long-term-debt ratio, etc. It is recommended that for mining enterprises, being high risk firms, the latter ratio be over 0.33:1 (the produced cash flow should cover the total debts in less than three years). The method described makes use of the ratio of various items of an annual balance in order to assess the value and credit worthiness of a mining enterprise. The possibility of a take-over, and investment risk are also evaluated. 11 refs.
Single gate optimization for plastic injection mold
Institute of Scientific and Technical Information of China (English)
LI Ji-quan; LI De-qun; GUO Zhi-ying; LV Hai-yuan
2007-01-01
This paper deals with a methodology for single gate location optimization for plastic injection mold. The objective of the gate optimization is to minimize the warpage of injection molded parts, because warpage is a crucial quality issue for most injection molded parts while it is influenced greatly by the gate location. Feature warpage is defined as the ratio of maximum displacement on the feature surface to the projected length of the feature surface to describe part warpage. The optimization is combined with the numerical simulation technology to find the optimal gate location, in which the simulated annealing algorithm is used to search for the optimum. Finally, an example is discussed in the paper and it can be concluded that the proposed method is effective.
Optimal obstacle control problem
Institute of Scientific and Technical Information of China (English)
ZHU Li; LI Xiu-hua; GUO Xing-ming
2008-01-01
In the paper we discuss some properties of the state operators of the optimal obstacle control problem for elliptic variational inequality. Existence, uniqueness and regularity of the optimal control problem are established. In addition, the approximation of the optimal obstacle problem is also studied.
Schaft, A.J. van der
1987-01-01
It is argued that the existence of symmetries may simplify, as in classical mechanics, the solution of optimal control problems. A procedure for obtaining symmetries for the optimal Hamiltonian resulting from the Maximum Principle is given; this avoids the actual calculation of the optimal
Drop cost and wavelength optimal two-period grooming with ratio 4
Bermond, Jean-Claude; Gionfriddo, Lucia; Quattrocchi, Gaetano; Valls, Ignasi Sau
2009-01-01
We study grooming for two-period optical networks, a variation of the traffic grooming problem for WDM ring networks introduced by Colbourn, Quattrocchi, and Syrotiuk. In the two-period grooming problem, during the first period of time, there is all-to-all uniform traffic among $n$ nodes, each request using $1/C$ of the bandwidth; and during the second period, there is all-to-all uniform traffic only among a subset $V$ of $v$ nodes, each request now being allowed to use $1/C'$ of the bandwidth, where $C' < C$. We determine the minimum drop cost (minimum number of ADMs) for any $n,v$ and C=4 and $C' \\in \\{1,2,3\\}$. To do this, we use tools of graph decompositions. Indeed the two-period grooming problem corresponds to minimizing the total number of vertices in a partition of the edges of the complete graph $K_n$ into subgraphs, where each subgraph has at most $C$ edges and where furthermore it contains at most $C'$ edges of the complete graph on $v$ specified vertices. Subject to the condition that the two-p...
DS-OPTIMAL DESIGNS FOR STUDYING COMBINATIONS OF CHEMICALS USING MULTIPLE FIXED-RATIO RAY EXPERIMENTS
ABSTRACT Detecting and characterizing interactions among chemicals is an important environmental issue. Traditional factorial designs become infeasible as the number of compounds under study increases. Ray designs, which reduce the amount of experimental effort, can be...
Directory of Open Access Journals (Sweden)
FarzinPiltan
2013-08-01
Full Text Available In this research, model reference fuzzy based control is presented as robust controls for IC engine. The objective of the study is to design controls for IC engines without the knowledge of the boundary of uncertainties and dynamic information by using fuzzy model reference PD plus mass of air while improve the robustness of the PD plus mass of air control. A PD plus mass of air provides for eliminate the mass of air and ultimate accuracy in the presence of the bounded disturbance/uncertainties, although this methods also causes some oscillation. The fuzzy PD plus mass of air is proposed as a solution to the problems crated by unstability. This method has a good performance in presence of uncertainty.
[Down with odds ratios: risk ratios in cohort studies and randomised clinical trials].
Knol, Mirjam J
2012-01-01
Various effect measures are available for quantifying the relationship between an intervention or a risk factor and an outcome, such as the risk ratio and the odds ratio. Odds ratios are intended for use in case-control studies in which they are an appropriate measure for estimating the relative risk; however, this measure is also often presented in cohort studies and in randomized clinical trials. When used for cohort studies and randomized clinical trials, the odds ratio is often incorrectly interpreted as the risk ratio; the odds ratio then provides an overestimation of the risk ratio, especially when the outcome is frequent. The use of logistic regression to adjust for confounding is one of the reasons that odds ratios are presented. For cohort studies and randomized clinical trials, however, there are methods to estimate adjusted risk ratios; these include the Mantel-Haenszel method, log-binomial regression, Poisson regression with robust standard error, and 'doubling of cases' method with robust standard error. To avoid misinterpretation of odds ratios, risk ratios should be calculated in cohort studies and randomized clinical trials.
Residential long-term care capacity planning: the shortcomings of ratio-based forecasts.
Zhang, Yue; Puterman, Martin L; Atkins, Derek
2012-05-01
This paper uses observations from two British Columbia studies to illustrate the shortcomings of widely used ratio-based approaches for residential long-term care capacity planning. It shows that capacity plans based on a fixed ratio of beds per population over age 75 may result in either excess capacity or long wait times for admission. It then investigates the use of linear regression models to obtain a "best" ratio by relating optimal plans derived by rigorous analytical methods to population characteristics and shows that no single ratio applies broadly. While the use of regression is promising, finding these "best" ratios is too analytically complex for general practice. The paper concludes by providing and evaluating an easy-to-use planning method, which we call the average flow model (AFM). The AFM combines demand forecasts with length-of-stay estimates to produce enhanced capacity plans. The AFM is transparent, easily implemented in a spreadsheet and well suited for "what if?" analyses.
Optimization and optimal control in automotive systems
Kolmanovsky, Ilya; Steinbuch, Maarten; Re, Luigi
2014-01-01
This book demonstrates the use of the optimization techniques that are becoming essential to meet the increasing stringency and variety of requirements for automotive systems. It shows the reader how to move away from earlier approaches, based on some degree of heuristics, to the use of more and more common systematic methods. Even systematic methods can be developed and applied in a large number of forms so the text collects contributions from across the theory, methods and real-world automotive applications of optimization. Greater fuel economy, significant reductions in permissible emissions, new drivability requirements and the generally increasing complexity of automotive systems are among the criteria that the contributing authors set themselves to meet. In many cases multiple and often conflicting requirements give rise to multi-objective constrained optimization problems which are also considered. Some of these problems fall into the domain of the traditional multi-disciplinary optimization applie...
Optimal Load Dispatch Using Ant Lion Optimization
Directory of Open Access Journals (Sweden)
Menakshi Mahendru Nischal
2015-08-01
Full Text Available This paper presents Ant lion optimization (ALO technique to solve optimal load dispatch problem. Ant lion optimization (ALO is a novel nature inspired algorithm. The ALO algorithm mimics the hunting mechanism of ant lions in nature. Five main steps of hunting prey such as the random walk of ants, building traps, entrapment of ants in traps, catching preys, and re-building traps are implemented. Optimal load dispatch (OLD is a method of determining the most efficient, low-cost and reliable operation of a power system by dispatching available electricity generation resources to supply load on the system. The primary objective of OLD is to minimize total cost of generation while honoring operational constraints of available generation resources. The proposed technique is implemented on 3, 6 & 20 unit test system for solving the OLD. Numerical results shows that the proposed method has good convergence property and better in quality of solution than other algorithms reported in recent literature.
Particle Swarm Optimization Based Reactive Power Optimization
Sujin, P R; Linda, M Mary
2010-01-01
Reactive power plays an important role in supporting the real power transfer by maintaining voltage stability and system reliability. It is a critical element for a transmission operator to ensure the reliability of an electric system while minimizing the cost associated with it. The traditional objectives of reactive power dispatch are focused on the technical side of reactive support such as minimization of transmission losses. Reactive power cost compensation to a generator is based on the incurred cost of its reactive power contribution less the cost of its obligation to support the active power delivery. In this paper an efficient Particle Swarm Optimization (PSO) based reactive power optimization approach is presented. The optimal reactive power dispatch problem is a nonlinear optimization problem with several constraints. The objective of the proposed PSO is to minimize the total support cost from generators and reactive compensators. It is achieved by maintaining the whole system power loss as minimum...
Serial binary interval ratios improve rhythm reproduction.
Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao
2013-01-01
Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.
Serial binary interval ratios improve rhythm reproduction
Directory of Open Access Journals (Sweden)
Xiang eWu
2013-08-01
Full Text Available Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8, non-binary integer (1:3:5:6, and non-integer (1:2.3:5.3:6.4 ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.
Duty-ratio of cooperative molecular motors
Dharan, Nadiv
2012-01-01
Molecular motors are found throughout the cells of the human body, and have many different and important roles. These micro-machines move along filament tracks, and have the ability to convert chemical energy into mechanical work that powers cellular motility. Different types of motors are characterized by different duty-ratios, which is the fraction of time that a motor is attached to its filament. In the case of myosin II - a non-processive molecular machine with a low duty ratio - cooperativity between several motors is essential to induce motion along its actin filament track. In this work we use statistical mechanical tools to calculate the duty ratio of cooperative molecular motors. The model suggests that the effective duty ratio of non-processive motors that work in cooperation is lower than the duty ratio of the individual motors. The origin of this effect is the elastic tension that develops in the filament which is relieved when motors detach from the track.
Using financial ratios to assess physician practices.
Doelling, P M
1996-01-01
Purchasing physician practices has become commonplace in the health care environment today. The most commonly used method to evaluate a physician's practice is the medical practice assessment. Although assessments include examining revenues, expenses, staffing ratios, collection ratios and other pertinent statistics, one of the often overlooked financial areas is the balance sheet. Evaluating a business, such as a medical practice, requires a thorough examination of the total financial picture including assets, liabilities, owner's equity or net worth, and the relationship of all the variables to each other. Ratios put the numbers into perspective by creating relationships between the balance sheet variables of assets, liabilities and owner's equity, and key income statement components of revenues, expenses and net income. As a result, ratios provide a unique perspective to the assessment process and enable a more complete analysis. This article examines the types and uses of ratios to assist physicians, managers, and hospital executives to better evaluate the financial viability of a physician's solo or group practice.
A novel approach for optimal chiller loading using particle swarm optimization
Energy Technology Data Exchange (ETDEWEB)
Ardakani, A. Jahanbani; Ardakani, F. Fattahi; Hosseinian, S.H. [Department of Electrical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Hafez Avenue, Tehran 15875-4413 (Iran, Islamic Republic of)
2008-07-01
This study employs two new methods to solve optimal chiller loading (OCL) problem. These methods are continuous genetic algorithm (GA) and particle swarm optimization (PSO). Because of continuous nature of variables in OCL problem, continuous GA and PSO easily overcome deficiencies in other conventional optimization methods. Partial load ratio (PLR) of the chiller is chosen as the variable to be optimized and consumption power of the chiller is considered as fitness function. Both of these methods find the optimal solution while the equality constraint is exactly satisfied. Some of the major advantages of proposed approaches over other conventional methods can be mentioned as fast convergence, escaping from getting into local optima, simple implementation as well as independency of the solution from the problem. Abilities of proposed methods are examined with reference to an example system. To demonstrate these abilities, results are compared with binary genetic algorithm method. The proposed approaches can be perfectly applied to air-conditioning systems. (author)
Quasiconvex optimization and location theory
Santos Gromicho, Jaoquim António
1998-01-01
grams of which the objective is given by the ratio of a convex by a positive (over a convex domain) concave function. As observed by Sniedovich (Ref. [102, 103]) most of the properties of fractional pro grams could be found in other programs, given that the objective function could be written as a particular composition of functions. He called this new field C programming, standing for composite concave programming. In his seminal book on dynamic programming (Ref. [104]), Sniedovich shows how the study of such com positions can help tackling non-separable dynamic programs that otherwise would defeat solution. Barros and Frenk (Ref. [9]) developed a cutting plane algorithm capable of optimizing C-programs. More recently, this algorithm has been used by Carrizosa and Plastria to solve a global optimization problem in facility location (Ref. [16]). The distinction between global optimization problems (Ref. [54]) and generalized convex problems can sometimes be hard to establish. That is exactly the reason ...
Law of Conservation of the Capital-Output Ratio*
Samuelson, Paul A.
1970-01-01
Just as simple harmonic motion, definable by a variational condition, δ [unk] (½ ẋ2 - ½ x2) dt = 0, has motions which must conserve the sum of kinetic and potential energies, ½ ẋ2 + ½x2 ≅ constant, so in a neoclassical von Neumann economy, where all output is saved to provide capital formation for the system's growth, it will be true that there exists a conservation law—namely the constancy along any intertemporally-efficient motion of the capital-output ratio ΣPtjKtj/ΣPtjKt j. This is derived as an „energy” integral of a time-free integrand1 in an optimal-control problem of variational type. PMID:16591882
Signal-to-noise ratio of Singer product apertures
Shutler, Paul M. E.; Byard, Kevin
2017-09-01
Formulae for the signal-to-noise ratio (SNR) of Singer product apertures are derived, allowing optimal Singer product apertures to be identified, and the CPU time required to decode them is quantified. This allows a systematic comparison to be made of the performance of Singer product apertures against both conventionally wrapped Singer apertures, and also conventional product apertures such as square uniformly redundant arrays. For very large images, equivalently for images at very high resolution, the SNR of Singer product apertures is asymptotically as good as the best conventional apertures, but Singer product apertures decode faster than any conventional aperture by at least a factor of ten for image sizes up to several megapixels. These theoretical predictions are verified using numerical simulations, demonstrating that coded aperture video is for the first time a realistic possibility.
High pressure ratio cryocooler with integral expander and heat exchanger
Crunkleton, J. A.; Smith, J. L., Jr.; Iwasa, Y.
A new 1 W, 4.2 K cryocooler is under development that is intended to miniaturize helium temperature refrigeration systems using a high-pressure-ratio Collins-type cycle. The configuration resulted from optimization studies of a saturated vapor compression (SCV) cycle that employs miniature parallel-plate heat exchangers. The basic configuration is a long displacer in a close-fitting, thin-walled cylinder. The displacer-to-cylinder gap is the high-pressure passage of the heat exchanger, and the low-pressure passage is formed by a thin tube over the OD of the cylinder. A solenoid-operated inlet valve admits 40 atm helium to the displacer-to-cylinder gap at room temperature, while the solenoid-operated exhaust valve operates at 4 atm. The single-stage cryocooler produces 1 W of refrigeration at 40 K without precooling and at 20 K with liquid nitrogen precooling.
Injection Molding of High Aspect Ratio Nanostructures
DEFF Research Database (Denmark)
Matschuk, Maria; Larsen, Niels Bent
We present a process for injection molding of 40 nm wide and >100 nm high pillars (pitch: 200 nm). We explored the effects of mold coatings and injection molding conditions on the replication quality of nanostructures in cyclic olefin copolymer. We found that optimization of molding parameters...
Concepts of combinatorial optimization
Paschos, Vangelis Th
2014-01-01
Combinatorial optimization is a multidisciplinary scientific area, lying in the interface of three major scientific domains: mathematics, theoretical computer science and management. The three volumes of the Combinatorial Optimization series aim to cover a wide range of topics in this area. These topics also deal with fundamental notions and approaches as with several classical applications of combinatorial optimization.Concepts of Combinatorial Optimization, is divided into three parts:- On the complexity of combinatorial optimization problems, presenting basics about worst-case and randomi
Introduction to Continuous Optimization
DEFF Research Database (Denmark)
Andreasson, Niclas; Evgrafov, Anton; Patriksson, Michael
optimal solutions for continuous optimization models. The main part of the mathematical material therefore concerns the analysis and linear algebra that underlie the workings of convexity and duality, and necessary/sufficient local/global optimality conditions for continuous optimization problems. Natural...... algorithms are then developed from these optimality conditions, and their most important convergence characteristics are analyzed. The book answers many more questions of the form “Why?” and “Why not?” than “How?”. We use only elementary mathematics in the development of the book, yet are rigorous throughout...
Optimization theory with applications
Pierre, Donald A
1987-01-01
Optimization principles are of undisputed importance in modern design and system operation. They can be used for many purposes: optimal design of systems, optimal operation of systems, determination of performance limitations of systems, or simply the solution of sets of equations. While most books on optimization are limited to essentially one approach, this volume offers a broad spectrum of approaches, with emphasis on basic techniques from both classical and modern work.After an introductory chapter introducing those system concepts that prevail throughout optimization problems of all typ
Is the lecithin/sphingomyelin ratio outdated?
James, D K; Tindall, V R; Richardson, T
1983-11-01
The lecithin/sphingomyelin (L/S) ratio in amniotic fluid is an excellent predictor of fetal lung maturity in most pregnancies but today its value is limited. A review of the use of the L/S ratio service in Manchester from 1975 to 1981 (inclusive) shows a dramatic and consistent fall in the number of requests made over the last 18 months of this period resulting in inconvenience and inefficiency in the laboratory service. Possible explanations for the declining use of the L/S ratio service are discussed with particular reference to St Mary's Hospital, Manchester and a regional re-organization of laboratory assessment of fetal lung maturity is proposed.
A quantum framework for likelihood ratios
Bond, Rachael L; Ormerod, Thomas C
2015-01-01
The ability to calculate precise likelihood ratios is fundamental to many STEM areas, such as decision-making theory, biomedical science, and engineering. However, there is no assumption-free statistical methodology to achieve this. For instance, in the absence of data relating to covariate overlap, the widely used Bayes' theorem either defaults to the marginal probability driven "naive Bayes' classifier", or requires the use of compensatory expectation-maximization techniques. Equally, the use of alternative statistical approaches, such as multivariate logistic regression, may be confounded by other axiomatic conditions, e.g., low levels of co-linearity. This article takes an information-theoretic approach in developing a new statistical formula for the calculation of likelihood ratios based on the principles of quantum entanglement. In doing so, it is argued that this quantum approach demonstrates: that the likelihood ratio is a real quality of statistical systems; that the naive Bayes' classifier is a spec...
Co-composting of green waste and food waste at low C/N ratio.
Kumar, Mathava; Ou, Yan-Liang; Lin, Jih-Gaw
2010-04-01
In this study, co-composting of food waste and green waste at low initial carbon to nitrogen (C/N) ratios was investigated using an in-vessel lab-scale composting reactor. The central composite design (CCD) and response surface method (RSM) were applied to obtain the optimal operating conditions over a range of preselected moisture contents (45-75%) and C/N ratios (13.9-19.6). The results indicate that the optimal moisture content for co-composting of food waste and green waste is 60%, and the substrate at a C/N ratio of 19.6 can be decomposed effectively to reduce 33% of total volatile solids (TVS) in 12days. The TVS reduction can be modeled by using a second-order equation with a good fit. In addition, the compost passes the standard germination index of white radish seed indicating that it can be used as soil amendment.
Venter, Gerhard; Sobieszczanski-Sobieski Jaroslaw
2002-01-01
The purpose of this paper is to show how the search algorithm known as particle swarm optimization performs. Here, particle swarm optimization is applied to structural design problems, but the method has a much wider range of possible applications. The paper's new contributions are improvements to the particle swarm optimization algorithm and conclusions and recommendations as to the utility of the algorithm, Results of numerical experiments for both continuous and discrete applications are presented in the paper. The results indicate that the particle swarm optimization algorithm does locate the constrained minimum design in continuous applications with very good precision, albeit at a much higher computational cost than that of a typical gradient based optimizer. However, the true potential of particle swarm optimization is primarily in applications with discrete and/or discontinuous functions and variables. Additionally, particle swarm optimization has the potential of efficient computation with very large numbers of concurrently operating processors.
Integrated controls design optimization
Lou, Xinsheng; Neuschaefer, Carl H.
2015-09-01
A control system (207) for optimizing a chemical looping process of a power plant includes an optimizer (420), an income algorithm (230) and a cost algorithm (225) and a chemical looping process models. The process models are used to predict the process outputs from process input variables. Some of the process in puts and output variables are related to the income of the plant; and some others are related to the cost of the plant operations. The income algorithm (230) provides an income input to the optimizer (420) based on a plurality of input parameters (215) of the power plant. The cost algorithm (225) provides a cost input to the optimizer (420) based on a plurality of output parameters (220) of the power plant. The optimizer (420) determines an optimized operating parameter solution based on at least one of the income input and the cost input, and supplies the optimized operating parameter solution to the power plant.
Evolutionary constrained optimization
Deb, Kalyanmoy
2015-01-01
This book makes available a self-contained collection of modern research addressing the general constrained optimization problems using evolutionary algorithms. Broadly the topics covered include constraint handling for single and multi-objective optimizations; penalty function based methodology; multi-objective based methodology; new constraint handling mechanism; hybrid methodology; scaling issues in constrained optimization; design of scalable test problems; parameter adaptation in constrained optimization; handling of integer, discrete and mix variables in addition to continuous variables; application of constraint handling techniques to real-world problems; and constrained optimization in dynamic environment. There is also a separate chapter on hybrid optimization, which is gaining lots of popularity nowadays due to its capability of bridging the gap between evolutionary and classical optimization. The material in the book is useful to researchers, novice, and experts alike. The book will also be useful...
Interactive Topology Optimization
DEFF Research Database (Denmark)
Nobel-Jørgensen, Morten
software where the users are assumed to be well-educated both in the finite element method and topology optimization. This dissertation describes how various topology optimization methods have been used for creating cross-platform applications with high performance. The user interface design is based......Interactivity is the continuous interaction between the user and the application to solve a task. Topology optimization is the optimization of structures in order to improve stiffness or other objectives. The goal of the thesis is to explore how topology optimization can be used in applications...... in an interactive and intuitive way. By creating such applications with an intuitive and simple user interface we allow non-engineers like designers and architects to easily experiment with boundary conditions, design domains and other optimization settings. This is in contrast to commercial topology optimization...
Radioactive anomaly discrimination from spectral ratios
Maniscalco, James; Sjoden, Glenn; Chapman, Mac Clements
2013-08-20
A method for discriminating a radioactive anomaly from naturally occurring radioactive materials includes detecting a first number of gamma photons having energies in a first range of energy values within a predetermined period of time and detecting a second number of gamma photons having energies in a second range of energy values within the predetermined period of time. The method further includes determining, in a controller, a ratio of the first number of gamma photons having energies in the first range and the second number of gamma photons having energies in the second range, and determining that a radioactive anomaly is present when the ratio exceeds a threshold value.
A Generalized Savage-Dickey Ratio
Cameron, Ewan
2013-01-01
In this brief research note I present a generalized version of the Savage-Dickey Density Ratio for representation of the Bayes factor (or marginal likelihood ratio) of nested statistical models; the new version takes the form of a Radon-Nikodym derivative and is thus applicable to a wider family of probability spaces than the original (restricted to those admitting an ordinary Lebesgue density). A derivation is given following the measure-theoretic construction of Marin & Robert (2010), and the equivalent estimator is demonstrated in application to a distributional modeling problem.
Secular trends in newborn sex ratios.
Grech, Victor
2014-11-01
A wide variety of factors have been shown to influence the male to female ratio at birth, which invariably displays a male excess. This paper will review and amplify recent work by the author, with specific references to individual countries, regions and entire continents in order to provide a global overview of this subject. It will be shown that stress, including stress related to political events, influences this ratio. Man-made radiation is also shown to have played a significant role in relation to the Windscale fire (1957) and Chernobyl (1986). Copyright © 2014 Elsevier Ltd. All rights reserved.
Ultima Ratio as a Constitutional Principle
Directory of Open Access Journals (Sweden)
Kaarlo Tuori
2013-01-01
Full Text Available The paper argues the criminal law notion of ultima ratio is an instance of a broader constitutional law principle of proportionality. However, ultima ratio is not the only principle relevant in a constitutional assessment of criminalization. The role of ultima ratio is to impose limitations on criminalization. But constitutional doctrines also exist which call for criminalization and might even be seen as establishing a criminalization obligation. The paper examines three constitutional counter weights to ultima ratio. The first of these is discussed in the context of state constitutions. This is the cluster of the interrelated constitutional doctrines of the horizontal effect of fundamental rights and the protective duty of the state, as well as the understanding of collective security as a basic right. These doctrines are analysed in the light of the praxis of the German Constitutional Court and the Finnish Constitutional Law Committee. The two other constitutional counterweights are discussed at the level of the transnational, European constitution. These are the principles of precaution and effectiveness. Este artículo defiende que el concepto de ultima ratio es una instancia más amplia del principio de proporcionalidad dentro del derecho constitucional. Sin embargo, el ultima ratio no es el único principio relevante en la valoración constitucional de la criminalización. El papel del ultima ratio es imponer límites a la criminalización. Pero también existen doctrinas constitucionales que exigen la criminalización e incluso dan pie a entender que obligan a establecer una pena. El documento examina tres contrapesos constitucionales al ultima ratio. En primer lugar, se analiza en el contexto de las constituciones estatales. Este es el conjunto de las doctrinas constitucionales interrelacionadas entre el efecto horizontal de los derechos fundamentales y el deber de protección del Estado, así como la asunción de la seguridad colectiva
The golden ratio and Fibonacci numbers
Dunlap, Richard A
1997-01-01
In this invaluable book, the basic mathematical properties of the golden ratio and its occurrence in the dimensions of two- and three-dimensional figures with fivefold symmetry are discussed. In addition, the generation of the Fibonacci series and generalized Fibonacci series and their relationship to the golden ratio are presented. These concepts are applied to algorithms for searching and function minimization. The Fibonacci sequence is viewed as a one-dimensional aperiodic, lattice and these ideas are extended to two- and three-dimensional Penrose tilings and the concept of incommensurate p