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41.
This paper describes a comparative analysis of the suitability of three artificial diets for the development of the cherry bark tortrix (CBT), Enarmonia formosana Scopoli (Lepidoptera: Tortricidae), to simplify the rearing process for this species and its potential classical biological control agents. The three diets tested included (1) a pinto bean-based diet modified specifically for the CBT, (2) the diet for codling moth, Cydia pomonella Linnaeus (Lepidoptera: Tortricidae), and (3) the Singh general-purpose diet. Survival from first instar to the pupal stage was very low on the pinto bean, codling moth, and Singh general-purpose diets (29, 0, and 0%, respectively). Survival was consistently greater, yet still low, for larvae that were reared through the first instar on bark and subsequently transferred to the codling moth or Singh general-purpose diets (5 and 32%, respectively). In comparison, larvae started on the pinto bean diet as second instars had a survival rate of 90%, only slightly below that of sibling larvae from the cherry bark control group (100%). Larval development time was fastest on cherry bark (36±2?days), differing significantly from that on the pinto bean diet (started as first instars: 58±2?days; started as second instars: 46±2?days), but not from the development time of larvae on the Singh general-purpose diet (44±3?days). Pupal weights were greatest for specimens from the Singh general-purpose diet (14.9±0.5?mg) and lowest for those from the pinto bean diet (started as first instar: 12.3±0.6?mg; started as second instar: 12.1±0.4?mg). Pupal weights from cherry bark were intermediate (13.5±0.6?mg). Early mortality, resulting primarily from rejection of the diet, remains to be the critical impediment in CBT rearing. It is therefore suggested that a phagostimulant from cherry bark be identified and included in an artificial diet shown to be nutritionally suitable, such as the Singh general-purpose diet or the pinto bean diet. 相似文献
42.
Denise K. Houston June Stevens Jianwen Cai Miriam C. Morey 《Obesity (Silver Spring, Md.)》2005,13(10):1793-1802
Objective: To examine associations of weight history with functional limitations and disability in white and African‐American men and women. Research Methods and Procedures: Data were from the Atherosclerosis Risk in Communities study (n = 11, 177). Associations of recalled weight status at age 25 and weight change from age 25 to ages 45 to 64 with functional limitations, activities of daily living (ADLs), and instrumental activities of daily living (IADLs) at follow‐up (ages 52 to 75) were examined using logistic regression. Results: Obesity (BMI ≥ 30 kg/m2) at age 25 was associated with functional limitations and ADL and IADL impairment at follow‐up in white and African‐American men and women. For example, obese compared with normal weight (BMI, 18.5 to 24.9 kg/m2) white women had higher odds of mild [odds ratio (95% confidence interval), 1.97 (1.18 to 3.29)] and severe [9.81 (5.92 to 16.27)] functional limitations and ADL [3.48 (2.36 to 5.13)] and IADL [2.95 (2.00 to 4.33)] impairment. In African‐American women, obesity was associated with higher odds of mild [2.71 (1.14 to 6.41)] and severe [6.01 (2.53 to 14.26)] functional limitations and ADL [1.82 (1.10 to 3.00)] and IADL [2.39 (1.47 to 3.90)] impairment. Similar associations were found in men. Compared with weight maintenance (±10 lbs), large weight gain (>30 lbs) from age 25 to ages 45 to 64 was also associated with functional limitations and ADL and IADL impairment in white and African‐American men and women. Discussion: Maintenance of a healthy body weight throughout adulthood may play a role in preventing or delaying the onset of functional limitations and disability, resulting in increased quality of life and decreased health care costs. 相似文献
43.
Weight Stigmatization and Ideological Beliefs: Relation to Psychological Functioning in Obese Adults
Kelli E. Friedman Simona K. Reichmann Philip R. Costanzo Arnaldo Zelli Jamile A. Ashmore Gerard J. Musante 《Obesity (Silver Spring, Md.)》2005,13(5):907-916
Objective: This study evaluated the relation among weight‐based stigmatization, ideological beliefs about weight, and psychological functioning in an obese, treatment‐seeking sample. Research Methods and Procedure: Ninety‐three obese, treatment‐seeking adults (24 men and 69 women) completed a battery of self‐report questionnaires measuring psychological adjustment, attitudes about weight, belief in the controllability of weight, and the frequency of weight‐based stigmatization. Results: Weight‐based stigmatization was a common experience for participants. Frequency of stigmatizing experiences was positively associated with depression, general psychiatric symptoms, and body image disturbance, and negatively associated with self‐esteem. Further, participants’ own negative attitudes about weight problems were associated with their psychological distress and moderated the relation between the experience of stigmatization and body image. Discussion: Weight‐based stigmatization is a common experience for obese individuals seeking weight loss treatment and appears to contribute to poor mental health adjustment. The negative effects of these experiences are particularly damaging for those who hold strong antifat beliefs. 相似文献
44.
Hung‐Yuan Li Wei‐Jei Lee Mei‐Ju Chen Lee‐Ming Chuang 《Obesity (Silver Spring, Md.)》2005,13(5):855-861
Objective: The association between circulating vascular adhesion protein‐1 (VAP‐1) and metabolic phenotypes has been shown to be inconsistent. The current study explored whether the changes in serum VAP‐1 levels correlate with the changes in metabolic phenotypes after weight reduction surgery. Research Methods and Procedures: Clinical characteristics and serum VAP‐1 levels in 20 morbidly obese subjects (mean BMI 38.84 kg/m2) were measured before and after vertical banded gastroplasty. Results: Before surgery, serum VAP‐1 levels correlated positively with fasting plasma glucose (γ = 0.56, p = 0.01) and negatively with insulin levels (γ = ?0.51, p = 0.021). After surgery, the changes in serum VAP‐1 levels were negatively correlated with the changes in waist circumference (γ = ?0.57, p = 0.011), diastolic blood pressure (DBP) (γ = ?0.56, p = 0.015), and mean arterial pressure (γ = ?0.46, p = 0.055). In multivariate regression, serum VAP‐1 levels were negatively correlated with waist circumference (β = ?2.36, p = 0.014) and DBP (β = ?3.02, p = 0.017) after adjusting for age and gender. The change in DBP was negatively correlated with the change in VAP‐1 levels after adjusting for age, gender, and steady‐state plasma glucose. Discussion: The results suggest that VAP‐1 levels are correlated with fasting glucose and insulin levels in morbidly obese subjects. After surgery, the changes in VAP‐1 levels were associated with changes in visceral adiposity and DBP. Serum VAP‐1 might modulate DBP independently from the changes in insulin resistance in morbidly obese people. 相似文献
45.
Armen E. Aghajanyan Artur A. Hambardzumyan Anichka S. Hovsepyan Rafael A. Asaturian Andranik A. Vardanyan Ashot A. Saghiyan 《Pigment cell & melanoma research》2005,18(2):130-135
Melanins are widely used in medicine, pharmacology, cosmetics and other fields. Although several technologies for the purification of water‐insoluble dioxyphenylalanine (DOPA) melanins have been described, a source of water‐soluble melanin is highly desirable. Here we describe an effective procedure for the isolation and purification of water‐soluble melanin using the culture medium of Bacillus thuringiensis subsp. galleriae strain K1. Water‐soluble melanin from this organism has an isoelectric point (pI = 3.0–3.2) and was purified optimally by adsorbtion using the IA‐1r resin and elution as a concentrated solution. The purified melanin obtained exhibited a similar infra‐red absorbtion spectrum to synthetic melanin and contained quinolic and phenolic structures and an amino acid content of around 20% after acid hydrolysis. The molecular weight of the purified melanin determined by SDS‐PAGE was 4 kDa and the electromagnetic spin resonance spectrum of the purified microbial melanin was a slightly asymmetric singlet without hyperfine structure with about 7 Gauss width of the line between points of the maximum incline and g = 2.006. The concentration of paramagnetic centers in melanin is 0.21 × 1018 spin/g. The results obtained provide a rapid, simple and inexpensive method for the large scale purification of water soluble melanin that may have widespread applications. 相似文献
46.
Sheila M. Williams 《Obesity (Silver Spring, Md.)》2005,13(6):1123-1130
Objective: Adiposity rebound occurs when the ratio of the velocities of log(weight) to log(height) changes from <2 to >2. This study examined the timing of adiposity rebound in the context of the velocities of weight and height in early childhood because it is not known whether faster weight gain or slower gain in stature is the more important determinant. Research Methods and Procedures: This was a longitudinal study of 406 boys and 397 girls born in Dunedin, New Zealand, in 1972 and 1973. Each child's height and weight were measured at 3 years of age and at least twice more as part of their two yearly assessments until 11 years of age. Results: The mean age of adiposity rebound was 6.6 ± 1.10 years (SD) for boys and 6.0 ± 1.21 years for girls. After adjusting for sex, the correlations between the timing of rebound and z‐scores for BMI, weight, and height at rebound were ?0.35, ?0.30, and ?0.14, respectively. Correlations between the timing of rebound and estimated values of weight and height velocities at 3 years were ?0.48 and ?0.00. The correlations with BMI and waist girth at 26 years were ?0.39 and ?0.35. Discussion: Children with an earlier adiposity rebound were heavier and had above average BMIs. Early rebound is the result of higher rates of weight gain, measured in percentage terms, rather than slower than average accrual of stature. This suggests that restraining weight gain could delay adiposity rebound and prevent obesity in early adulthood. 相似文献
47.
Earl S. Ford Ali H. Mokdad Wayne H. Giles Deborah A. Galuska Mary K. Serdula 《Obesity (Silver Spring, Md.)》2005,13(1):118-122
Objective: To examine the variation in the prevalences of obesity and type 2 diabetes in weight loss counseling by health providers and in other potential obesity‐related determinants in 100 metropolitan statistical areas in the United States. Research Methods and Procedures: We performed a cross‐sectional study using data from the 2000 Behavioral Risk Factor Surveillance System, the largest telephone survey of health behaviors in the United States, of age‐adjusted prevalence of obesity, type 2 diabetes, intake of ≥five servings of fruits and vegetables per day, participation in 150 minutes of leisure‐time physical activity per week, receipt of weight management advice, and reports of trying to lose or maintain weight among men and women more than 18 years old. Results: The age‐adjusted prevalence of obesity ranged from 13.1% to 30.0% and that of type 2 diabetes from 3.3% to 9.2%. Among participants who had visited a physician for a routine checkup in the previous 12 months, 13.1% to 27.1% of all participants recalled receiving advice from a health professional about their weight, and 11.7% to 34.6% of overweight or obese participants recalled receiving advice to maintain or lose weight. Discussion: Significant differences in the prevalence of obesity and self‐reported type 2 diabetes and in medical practice patterns regarding weight management advice exist among metropolitan statistical areas. These results suggest important opportunities to investigate reasons for these variations that could potentially be used to mitigate the current epidemic of obesity and to identify areas where obesity and diabetes prevention efforts may need to be targeted. 相似文献
48.
Josep A. Tur Lluís Serra‐Majem Dora Romaguera Antoni Pons 《Obesity (Silver Spring, Md.)》2005,13(3):527-536
Objective: To assess the prevalence of excess weight (obesity and overweight) and the related environmental risk factors in a Mediterranean population. Self‐perception of body weight, attitudes toward weight‐control behaviors, and the associated factors were also examined. Research Methods and Procedures: A cross‐sectional nutritional survey was carried out in the Balearic Islands between 1999 and 2000. A random sample (n = 1200) of the adult population (20 to 60 years old) was interviewed. Dietary questionnaires and a global questionnaire incorporating questions related to sociodemographic and lifestyle variables were utilized. Anthropometric measurements were also obtained. Results: Nearly one‐half of the population of the Balearic Islands is above the normal weight range (BMI > 25). The predictors of overweight and obesity in the Balearic Islands are to be over 40 years old, to be married, to form part of the lowest educational levels, and to have a sedentary lifestyle. A large percentage of excess‐weight individuals tend to underestimate their BMI, are not concerned about their weight status, tend to snack more often, and have never dieted. Discussion: Although the likely causes of the rise in obesity prevalence are difficult to elucidate from this study, we have identified the profile of individuals with excess weight in the Balearic Islands as well as their attitudes toward their body image. 相似文献
49.
Hiroyuki Matsuda 《人类与生态风险评估》2005,11(1):189-200
Aim. Before intergovernmental consensus under the Rio Declaration in 1992, ignorance of type I errors had been disfavoured in science. However, the Precautionary Principle (PP) counsels the avoidance of type II errors, rather than of type I errors. We need a new academic code for the PP. Material and methods. The risk of extinction has usually been evaluated based on conservative estimates of the present population size. I define the weight of evidence as the extinction risk of Japanese vascular plants based on unbiased estimates. Catch quotas in the fisheries are usually decided by precautionary approach. I calculate the long-term yield and risk of stock collapse under a simple stock dynamics model. Results. The weight of evidence depends on the frequency of grids with size unknown. In a few plant species, rankings based on conservative estimates have differed from rankings based on unbiased estimates. In fishery management, a catch quota based on a precautionary approach proved neither sufficient nor necessary to avoid stock collapse. The precautionary approach is one of the reasons that prevent us from maximizing a sustainable yield. Conclusions. We need to clarify the endpoint of risks, and check whether it is necessary to adopt a PP. We can obtain the weight of evidence that is measured under unbiased estimates, while the risk based on a PP is measured under conservative estimates. 相似文献
50.
Shifting nonbreeding distributions of migratory fauna in relation to climatic change 总被引:1,自引:0,他引:1
The distributions of eight out of nine common species of waders (Charadrii) overwintering on UK estuaries have changed in association with recent climate change. These birds represent a high proportion of various populations from breeding grounds as far apart as Greenland to the west to high‐arctic Russia to the east. During warmer winters, smaller proportions of seven species wintered in south‐west Britain. The distributions of the smaller species show the greatest temperature dependence. The opposite was found for the largest species and no relationship was found for a particularly site‐faithful species. In north‐west Europe, the winter isotherms have a broadly north to south alignment, with the east being colder than the west. The average minimum winter temperatures across the UK having increased by about 1.5°C since the mid‐1980s, the temperatures on the east coast during recent winters have been similar to those of the west coast during the mid‐1980s. On average, estuaries on the east and south coasts of Britain have muddier sediments than those on the west coast and thus support a higher biomass of the invertebrate prey of waders. We suggest that, with global climatic change, the advantage gained by waders wintering in the milder west to avoid cold weather‐induced mortality is diminished. Consequently, more choose to winter in the east and thus benefit from better foraging opportunities. The implications of these results are considered in terms of a site‐based approach to wildlife protection used in Europe and elsewhere. 相似文献