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Calorie restriction (CR) enhances immune response and prolongs life span in animals. However, information on the applicability of these results to humans is limited. T-cell function declines with age. We examined effects of CR on T-cell function in humans. Forty-six overweight, nonobese participants aged 20-42 years were randomly assigned to 30% or 10% CR group for 6 months. Delayed-type hypersensitivity (DTH), T-cell proliferation (TP), and prostaglandin E(2) (PGE(2)) productions were determined before and after CR. DTH and TP to T-cell mitogens were increased in both groups over baseline (p < or = .019). However, number of positive responses to DTH antigens (p = .016) and TP to anti-CD3 reached statistical significance only after 30% CR (p = .001). Lipopolysaccharide-stimulated PGE(2) was reduced in both groups but reached statistical significance after 30% CR (p < or = .029). These results, for the first time, show that 6-month CR in humans improves T-cell function. [ABSTRACT FROM AUTHOR]

BACKGROUND AND AIMS: Caloric restriction (CR) attenuates biological aging in animal models but there is little information on the feasibility and efficacy of CR regimens in humans. We examined the effects of consuming an insoluble cereal fiber supplement on ability to sustain CR over 1 year in healthy overweight adults. MEHODS: In 34 healthy overweight women and men (BMI 25-30 kg/m2, age 20-42 yr), a 30% CR regimen meeting national recommendations for dietary fiber was provided for 24 weeks, and for an additional 24 weeks subjects were counseled to prepare the same regimen at home. During 5-10 weeks of CR, subjects were randomized to consume an extra 20 g/day of dietary fiber from a high fiber cereal (+F) or to not consume additional fiber (-F). After this time, all subjects were encouraged to consume the extra fiber. Outcomes included adherence to the provided and self-prepared CR regimens (energy intake determined using doubly labeled water), changes in body weight, and self-reported satisfaction with the amount of consumed food. RESULTS: During 5-10 weeks of CR when all food was provided, both +F and -F groups were highly adherent to the CR regimen and there was no significant difference between groups in energy intake (p=0.51), weight change (p=0.96), or satisfaction with amount of provided food (p=0.08). During self-prepared CR from 25 to 48 weeks, mean adherence was lower than during the food-provided phase and there was a significant association between fiber intake and % CR (r=0.69, p<0.001), decreased BMI (r=- 0.38, p=0.04) and satisfaction with the amount of consumed food (r=0.59, p=0.002). CONCLUSIONS: A high fiber cereal intake may facilitate CR in humans self-selecting their own food; longer-term intervention studies are needed to confirm these findings. [ABSTRACT FROM AUTHOR]

Quantum algorithms provide an exponential speedup for solving certain classes of linear systems, including those that model geologic fracture flow. However, this revolutionary gain in efficiency does not come without difficulty. Quantum algorithms require that problems satisfy not only algorithm-specific constraints, but also application-specific ones. Otherwise, the quantum advantage carefully attained through algorithmic ingenuity can be entirely negated. Previous work addressing quantum algorithms for geologic fracture flow has illustrated core algorithmic approaches while incrementally removing assumptions. This work addresses two further requirements for solving geologic fracture flow systems with quantum algorithms: efficient system state preparation and efficient information extraction. Our approach to addressing each is consistent with an overall exponential speed-up., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Solving large systems of equations is a challenge for modeling natural phenomena, such as simulating subsurface flow. To avoid systems that are intractable on current computers, it is often necessary to neglect information at small scales, an approach known as coarse-graining. For many practical applications, such as flow in porous, homogenous materials, coarse-graining offers a sufficiently-accurate approximation of the solution. Unfortunately, fractured systems cannot be accurately coarse-grained, as critical network topology exists at the smallest scales, including topology that can push the network across a percolation threshold. Therefore, new techniques are necessary to accurately model important fracture systems. Quantum algorithms for solving linear systems offer a theoretically-exponential improvement over their classical counterparts, and in this work we introduce two quantum algorithms for fractured flow. The first algorithm, designed for future quantum computers which operate without error, has enormous potential, but we demonstrate that current hardware is too noisy for adequate performance. The second algorithm, designed to be noise resilient, already performs well for problems of small to medium size (order 10-1000 nodes), which we demonstrate experimentally and explain theoretically. We expect further improvements by leveraging quantum error mitigation and preconditioning., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Theoretical calculations suggest that small daily reductions in energy intake can cumulatively lead to substantial weight loss, but experimental data to support these calculations are lacking. We conducted a 1-year randomized controlled pilot study of low (10%) or moderate (30%) energy restriction (ER) with diets differing in glycemic load in 38 overweight adults (mean +/- s.d., age 35 +/- 6 years; BMI 27.6 +/- 1.4 kg/m(2)). Food was provided for 6 months and self-selected for 6 additional months. Measurements included body weight, resting metabolic rate (RMR), adherence to the ER prescription assessed using (2)H(2)(18)O, satiety, and eating behavior variables. The 10%ER group consumed significantly less energy (by (2)H(2)(18)O) than prescribed over 12 months (18.1 +/- 9.8%ER, P = 0.04), while the 30%ER group consumed significantly more (23.1 +/- 8.7%ER, P < 0.001). Changes in body weight, satiety, and other variables were not significantly different between groups. However, during self-selected eating (6-12 months) variability in % weight change was significantly greater in the 10%ER group (P < 0.001) and poorer weight outcome on 10%ER was predicted by higher baseline BMI and greater disinhibition (P < 0.0001; adj R(2) = 0.71). Weight loss at 12 months was not significantly different between groups prescribed 10 or 30%ER, supporting the efficacy of low ER recommendations. However, long-term weight change was more variable on 10%ER and weight change in this group was predicted by body size and eating behavior. These preliminary results indicate beneficial effects of low-level ER for some but not all individuals in a weight control program, and suggest testable approaches for optimizing dieting success based on individualizing prescribed level of ER.

Energy-restricted low glycemic load diets are being used increasingly for weight loss. However, the long-term effects of such regimens on mood and cognitive performance are not known. We assessed the effects of low glycemic load (LG) and high glycemic load (HG) energy-restricted diets on mood and cognitive performance during 6 months of a randomized controlled trial when all food was provided. Subjects were 42 healthy overweight adults (age 35+/-5 years; BMI 27.8+/-1.6 kg/m(2)) with a mean weight loss of 8.7+/-5.0% that did not differ significantly by diet randomization. Mood was assessed by using the Profile of Mood States (POMS) questionnaire. Cognitive performance was assessed by using computerized tests of simple reaction time, vigilance, learning, short-term memory and attention, and language-based logical reasoning. Worsening mood outcome over time was observed in the HG diet group compared to the LG for the depression subscale of POMS (p=0.009 after including hunger as a covariate). There was no significant change over time in any cognitive performance values. These findings suggest a negative effect of an HG weight loss diet on sub-clinical depression but, in contrast to a previous suggestion, provide no support for differential effects of LG versus HD diets on cognitive performance.

Objective: To examine characteristics of craved foods in relation to dietary energy restriction (ER) with high (HG) and low glycemic load (LG) diets., Design: Assessments of food cravings before and during a randomized controlled trial of HG and LG diets provided for 6 months., Subjects: Thirty-two healthy, overweight women aged 20-42 years., Measurements: Self-reported food cravings and dietary intake, body weight, weight history and measures of eating behaviors., Results: Foods craved at baseline were more than twice as high in energy density as the habitual diet (3.7+/-1.5 vs 1.7+/-0.3 kcal/g; P<0.001), and on average were lower in protein (P<0.001) and fiber (P<0.001) and higher in fat (P=0.002). There were no statistically significant changes in nutritional characteristics of craved foods after 6 months of ER. There was a significant relationship between reported portion size of craved food consumed at baseline and lifetime high body mass index (r=0.49, P=0.005). Additionally, there was a significant association between susceptibility to hunger and craving frequency at baseline, and there were significant relationships between hunger score, craving frequency, strength and percentage of time that cravings are given in to after 6 months of ER. In multiple regression models, subjects who lost a greater percentage of weight craved higher energy-dense foods at month 6 of ER, but also reported giving in to food cravings less frequently (adjusted R (2)=0.31, P=0.009)., Conclusion: High energy density and fat content, and low protein and fiber contents were identifying characteristics of craved foods. The relationships between craving variables and hunger score suggest that the relative influence of hunger susceptibility on cravings may be important before and especially after ER. Portion size of craved foods and frequency of giving in to food cravings appear to be important areas for focus in lifestyle modification programs for long-term weight loss.

A randomized controlled trial of high glycemic load (HG) and low glycemic load (LG) diets with food provided for 6 months and self-administered for 6 additional months at 30% caloric restriction (CR) was performed in 29 overweight adults (mean+/-SD, age 35+/-5y; BMI 27.5+/-1.5 kg/m(2)). Total energy expenditure (TEE), resting metabolic rate (RMR), fat and fat free mass (FFM), were measured at 3, 6 and 12 months. Changes in TEE, but not changes in RMR, were greater than accounted for by the loss of FFM and fat mass (P=0.001-0.013) suggesting an adaptive response to long-term CR. There was no significant effect of diet group on change in RMR or TEE. However, in subjects who lost >5% body weight (n=26), the LG diet group had a higher percentage of weight loss as fat than the HG group (p<0.05), a finding that may have implications for dietary recommendations during weight reduction.

Background: There remains no consensus about the optimal dietary composition for sustained weight loss., Objective: The objective was to examine the effects of 2 dietary macronutrient patterns with different glycemic loads on adherence to a prescribed regimen of calorie restriction (CR), weight and fat loss, and related variables., Design: A randomized controlled trial (RCT) of diets with a high glycemic load (HG) or a low glycemic load (LG) at 30% CR was conducted in 34 healthy overweight adults with a mean (+/-SD) age of 35 +/- 6 y and body mass index (kg/m(2)) of 27.6 +/- 1.4. All food was provided for 6 mo in diets controlled for confounding variables, and subjects self-administered the plans for 6 additional months. Primary and secondary outcomes included energy intake measured by doubly labeled water, body weight and fatness, hunger, satiety, and resting metabolic rate., Results: All groups consumed significantly less energy during CR than at baseline (P < 0.01), but changes in energy intake, body weight, body fat, and resting metabolic rate did not differ significantly between groups. Both groups ate more energy than provided (eg, 21% and 28% CR at 3 mo and 16% and 17% CR at 6 mo with HG and LG, respectively). Percentage weight change at 12 mo was -8.04 +/- 4.1% in the HG group and -7.81 +/- 5.0% in the LG group. There was no effect of dietary composition on changes in hunger, satiety, or satisfaction with the amount and type of provided food during CR., Conclusions: These findings provide more detailed evidence to suggest that diets differing substantially in glycemic load induce comparable long-term weight loss.