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91.
This study analyzed the environmental impacts of packaging‐derived changes in food production and consumer behavior to assist packaging designers in making environmentally conscious decisions. Packaging can be functionalized to prevent food loss and waste (FLW), for example, extending the expiration date and apportioning the package size, but it can generate additional environmental impacts from changes in food and packaging production. Previous studies assessed additional impacts from packaging production; however, the effects of packaging functionalization are yet to be connected with food production and consumer behavior. To examine the effect of functionalization on these aspects, we analyzed packaging‐derived changes in food production for milk and cabbage products. The case study compared products with functionalized packaging that permits a longer expiration date or a smaller portion size to their base‐case products. Our results showed that the packaging‐derived changes increased the global warming potential (GWP) of food production more than other processes did. Thus, changes in food production weakened the effectiveness of the packaging functionalization to decrease the GWP. Moreover, the analysis of consumer behavior scenarios showed that consumers’ perception of the expiration date decisively influences the effectiveness of packaging functionalization. When consumers discarded food after the expiration date, provided they consumed in small quantities, the packaging functionalization reduced FLW. From the scenario analysis, we identified appropriate combinations of packaging functionalization and consumer behaviors to effectively decrease total GWP. With our expanded analysis, packaging designers can understand the effectiveness of their decisions on the product life cycle in reducing FLW and environmental impacts.  相似文献   
92.
Haploinsufficiency is a form of genetic dominance and is the underlying mechanism of numerous human inherited conditions in which the causal genes are sensitive to altered dosage. This review examines the poorly understood relationships between haploinsufficiency, dosage sensitivity and genetic dominance, whose common theme is the existence of nonlinear relationships between genotype and phenotype. We present an up‐to‐date account of the bases of haploinsufficiency from the perspective of theoretical and experimental models. We also discuss human conditions caused by haploinsufficiency, including developmental syndromes and cancer. Connections between the understanding of these conditions' genetic mechanisms and advances in treatments are also described.  相似文献   
93.
Objective: The purpose of this study was to evaluate long‐term weight loss and eating and exercise behaviors of successful weight losers who lost weight using a low‐carbohydrate diet. Research Methods and Procedures: This study examined 3‐year changes in weight, diet, and physical activity in 891 subjects (96 low‐carbohydrate dieters and 795 others) who enrolled in the National Weight Control Registry between 1998 and 2001 and reported ≥30‐lb weight loss and ≥1 year weight loss maintenance. Results: Only 10.8% of participants reported losing weight after a low‐carbohydrate diet. At entry into the study, low‐carbohydrate diet users reported consuming more kcal/d (mean ± SD, 1895 ± 452 vs. 1398 ± 574); fewer calories in weekly physical activity (1595 ± 2499 vs. 2542 ± 2301); more calories from fat (64.0 ± 7.9% vs. 30.9 ± 13.1%), saturated fat (23.8 ± 4.1 vs. 10.5 ± 5.2), monounsaturated fat (24.4 ± 3.7 vs. 11.0 ± 5.1), and polyunsaturated fat (8.6 ± 2.7 vs. 5.5 ± 2.9); and less dietary restraint (10.8 ± 2.9 vs. 14.9 ± 3.9) compared with other Registry members. These differences persisted over time. No differences in 3‐year weight regain were observed between low‐carbohydrate dieters and other Registry members in intent‐to‐treat analyses (7.0 ± 7.1 vs. 5.7 ± 8.7 kg). Discussion: It is possible to achieve and maintain long‐term weight loss using a low‐carbohydrate diet. The long‐term health effects of weight loss associated with a high‐fat diet and low activity level merits further investigation.  相似文献   
94.
Objectives: The effect of national exercise recommendations on adiposity is unknown and may differ by sex. We examined long‐term effects of aerobic exercise on adiposity in women and men. Research Methods and Procedures: This was a 12‐month randomized, controlled clinical trial testing exercise effect on weight and body composition in men (N = 102) and women (N = 100). Sedentary/unfit persons, 40 to 75 years old, were recruited through physician practices and media. The intervention was facility‐ and home‐based moderate‐to‐vigorous intensity aerobic activity, 60 min/d, 6 days/wk vs. controls (no intervention). Results: Exercisers exercised a mean 370 min/wk (men) and 295 min/wk (women), and seven dropped the intervention. Exercisers lost weight (women, ?1.4 vs. +0.7 kg in controls, p = 0.008; men, ?1.8 vs. ?0.1 kg in controls, p = 0.03), BMI (women, ?0.6 vs. +0.3 kg/m2 in controls, p = 0.006; men, ?0.5 kg/m2 vs. no change in controls, p = 0.03), waist circumference (women, ?1.4 vs. +2.2 cm in controls, p < 0.001; men, ?3.3 vs. ?0.4 cm in controls, p = 0.003), and total fat mass (women, ?1.9 vs. +0.2 kg in controls, p = 0.001; men, ?3.0 vs. +0.2 kg in controls, p < 0.001). Exercisers with greater increases in pedometer‐measured steps per day had greater decreases in weight, BMI, body fat, and intra‐abdominal fat (all p trend < 0.05 in both men and women). Similar trends were observed for increased minutes per day of exercise and for increases in maximal oxygen consumption. Discussion: These data support the U.S. Department of Agriculture and Institute of Medicine guidelines of 60 min/d of moderate‐to‐vigorous physical activity.  相似文献   
95.
Objective: Body image dissatisfaction is common in treatment‐seeking patients with obesity. We aimed to investigate the effects of obesity management on body image in patients with obesity attending Italian medical centers for weight loss programs. Research Methods and Procedures: A total of 473 obese patients seeking treatment in 13 Italian medical centers (80% females; age, 45.9 ± standard deviation 11.0 years; BMI, 36.8 ± 5.7 kg/m2) were evaluated at baseline and after a 6‐month weight loss treatment. Body uneasiness, psychiatric distress, and binge eating were tested by Body Uneasiness Test (BUT, Part A), Symptom CheckList‐90 (SCL‐90), and Binge Eating Scale (BES), respectively. Results: At 6‐month follow‐up, the percentage weight loss was significantly higher in men (9.0 ± 6.3%) than in women (6.8 ± 7.3%; p = 0.010). Both men and women had a significant improvement in BUT Global Severity Index and in all of the BUT subscales with the exception of the Compulsive Self‐Monitoring subscale. Linear regression analysis selected baseline psychological and behavioral measures (global score of BUT and SCL‐90) and improved psychiatric distress and binge eating as independent predictors of changes in basal body dissatisfaction in females, whereas in males, changes were associated only with baseline BUT‐Global Severity Index score, binge eating, and its treatment‐associated improvement. Pre‐treatment BMI and BMI changes did not enter the regression. Discussion: Obesity treatment, even with a modest degree of weight loss, is associated with a significant improvement of body image, in both females and males. This effect depends mainly on psychological factors, not on the amount of weight loss.  相似文献   
96.
水分是限制干旱与半干旱地区植被恢复和农业发展的最重要因素之一,减少土壤水分无效蒸发损失可提高水分利用效率。凹凸棒土(ATP)作为一种黏土矿物,其亲水性和吸附性对限制土壤蒸发具有重要作用。本研究选取黄土高原干旱与半干旱区3种不同质地的典型土壤(黑垆土、黄绵土、风沙土),设置5种ATP添加量(0%、1%、2%、3%、4%),使用微型蒸发器在自然条件下进行土壤蒸发试验,探究ATP添加对不同土壤蒸发过程和蒸发面裂缝特征的影响。结果表明: 当ATP添加量<3%时,在同一种土壤下累积蒸发量与蒸发损失率随ATP添加量的增加而减小;ATP添加量为3%时,黑垆土、风沙土的累积蒸发量和蒸发损失率均减小,黄绵土的累积蒸发量和蒸发损失率增加;ATP添加量为4%时,黑垆土的累积蒸发量减小、蒸发损失率增加,风沙土的累积蒸发量增加、蒸发损失率减小,黄绵土的累积蒸发量和蒸发损失率均减小。不同土壤平均累积蒸发量表现为:黑垆土>黄绵土>风沙土。在同一种土壤的整个蒸发过程中,施加ATP处理的土壤含水量始终高于对照。累积蒸发量与时间平方根关系的模拟结果表明,蒸发结束时ATP处理下土壤样品可以释放的水量高于对照。添加ATP后黑垆土和黄绵土的裂缝面密度显著增加,风沙土裂缝面密度随ATP添加量的增加而增加,3种土壤的裂缝面密度在ATP添加量为4%时均达到最大值。ATP添加量为3%时可以在最大程度上减少土壤水分无效蒸发。  相似文献   
97.
The conversion of natural habitats to human land uses often increases local temperatures, creating novel thermal environments for species. The variable responses of ectotherms to habitat conversion, where some species decline while others persist, can partly be explained by variation among species in their thermal niches. However, few studies have examined thermal niche variation within species and across forest‐land use ecotones, information that could provide clues about the capacity of species to adapt to changing temperatures. Here, we quantify individual‐level variation in thermal traits of the tropical poison frog, Oophaga pumilio, in thermally contrasting habitats. Specifically, we examined local environmental temperatures, field body temperatures (Tb), preferred body temperatures (Tpref), critical thermal maxima (CTmax), and thermal safety margins (TSM) of individuals from warm, converted habitats and cool forests. We found that frogs from converted habitats exhibited greater mean Tb and Tpref than those from forests. In contrast, CTmax and TSM did not differ significantly between habitats. However, CTmax did increase moderately with increasing Tb, suggesting that changes in CTmax may be driven by microscale temperature exposure within habitats rather than by mean habitat conditions. Although O. pumilio exhibited moderate divergence in Tpref, CTmax appears to be less labile between habitats, possibly due to the ability of frogs in converted habitats to maintain their Tb below air temperatures that reach or exceed CTmax. Selective pressures on thermal tolerances may increase, however, with the loss of buffering microhabitats and increased frequency of extreme temperatures expected under future habitat degradation and climate warming. Abstract in Spanish is available with online material.  相似文献   
98.
The recovery process of aSasa tsuboiana population after a mass flowering and death in 1977 was investigated by 15 years of observation in the Hira Mountains, Kinki district, western Japan. Seed production was high (6600–13 800 seeds m−2 inSasa plots and 3900 seeds m−2 in a forest plot) but emergent seedling density was low (14–21 seedlings m−2), probably because of seed predation byMicrotus montebelli occurring between seed shedding and the next spring. The seedling density had decreased further by the next year and theS. tsuboiana population recovered from only a limited number of seedlings. In spite of such a low initial density, theS. tsuboiana population was able to regenerate successfully and attained the previous full stand height in 7–16 years.Miscantbus sinensis invaded and delayed the recovery ofS. tsuboiana in one plot, butS. tsuboiana became dominant as it caught up with the height ofM. sinensis. Seedling growth patterns, such as frequent tillering, the onset of rhizome extension in the early stage of seedling growth and frequent culm production from rhizomes, played important roles in the successful regeneration ofS. tsuboiana.  相似文献   
99.
The fertilized mouse egg actively demethylates the paternal genome within a few hours after fertilization, whereas the maternal genome is only passively demethylated by a replication-dependent mechanism after the two-cell stage. This evolutionarily conserved assymetry in the early diploid mammalian embryo may have a role in methylation reprogramming of the two very different sets of sperm and egg chromatin for somatic development and formation of totipotent cells. Immunofluorescence staining with an antibody against 5-methylcytosine (MeC) showed that the incidence of abnormal methylation patterns differs between mouse two-cell embryos from superovulated females, nonsuperovulated matings, and in vitro fertilization (IVF). It also depends on embryo culture conditions and genetic background. In general, there was a good correlation with the number of embryos (from the same experiment) which did not develop in vitro up to the blastocyst stage. Thus, aberrant genome-wide DNA methylation in early embryos may be an important mechanism contributing to the high incidence of developmental failure in mammals. Similar to the situation in abnormally methylated embryos from nuclear transfer, it may cause a high incidence of pregnancy loss and abnormal phenotypes.  相似文献   
100.
Sharing experiences and results among scientists and managers working on seagrass restoration was the main objective of the first European Seagrass Restoration Workshop that gathered researchers from around Europe. The meeting was the first forum in Europe that allowed for scientists, NGOs, and managers to interact and share their experiences relating to seagrass restoration and management. The results show that none of the seagrass restoration programs developed in Europe by the participants during the last 10 years was successful. Furthermore, an informal review of data published in seagrass restoration success, showed that the results reported were biased because they were mostly based on a very short monitoring period (i.e. < 1 year). Numerous decision trees, guidelines, and restoration models have been developed to aid seagrass restoration management, but the results of this workshop point toward a new paradigm in seagrass restoration were efforts should shift to give priority to natural restoration potential, with an emphasis on the fact that restoration should never be considered the first alternative when planning for the mitigation of coastal development projects or to justify mitigation as a compensation measure for economic activities.  相似文献   
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