Following critical evaluation of the available literature to date, The International Society of Sports Nutrition (ISSN) position regarding caffeine intake is as follows: 1. Supplementation with ...caffeine has been shown to acutely enhance various aspects of exercise performance in many but not all studies. Small to moderate benefits of caffeine use include, but are not limited to: muscular endurance, movement velocity and muscular strength, sprinting, jumping, and throwing performance, as well as a wide range of aerobic and anaerobic sport-specific actions. 2. Aerobic endurance appears to be the form of exercise with the most consistent moderate-to-large benefits from caffeine use, although the magnitude of its effects differs between individuals. 3. Caffeine has consistently been shown to improve exercise performance when consumed in doses of 3-6 mg/kg body mass. Minimal effective doses of caffeine currently remain unclear but they may be as low as 2 mg/kg body mass. Very high doses of caffeine (e.g. 9 mg/kg) are associated with a high incidence of side-effects and do not seem to be required to elicit an ergogenic effect. 4. The most commonly used timing of caffeine supplementation is 60 min pre-exercise. Optimal timing of caffeine ingestion likely depends on the source of caffeine. For example, as compared to caffeine capsules, caffeine chewing gums may require a shorter waiting time from consumption to the start of the exercise session. 5. Caffeine appears to improve physical performance in both trained and untrained individuals. 6. Inter-individual differences in sport and exercise performance as well as adverse effects on sleep or feelings of anxiety following caffeine ingestion may be attributed to genetic variation associated with caffeine metabolism, and physical and psychological response. Other factors such as habitual caffeine intake also may play a role in between-individual response variation. 7. Caffeine has been shown to be ergogenic for cognitive function, including attention and vigilance, in most individuals. 8. Caffeine may improve cognitive and physical performance in some individuals under conditions of sleep deprivation. 9. The use of caffeine in conjunction with endurance exercise in the heat and at altitude is well supported when dosages range from 3 to 6 mg/kg and 4-6 mg/kg, respectively. 10. Alternative sources of caffeine such as caffeinated chewing gum, mouth rinses, energy gels and chews have been shown to improve performance, primarily in aerobic exercise. 11. Energy drinks and pre-workout supplements containing caffeine have been demonstrated to enhance both anaerobic and aerobic performance.
•The international evidence clearly shows that purely qualitative forward guidance does little to anchor expectations of future policy rates.•Forward guidance that conditions the duration of low ...rates on observable macroeconomic outcomes anchors expectations of future policy rates quite well.•Forward guidance that pledges to keep rates low through a specified calendar date has a mixed record. It worked well in the United States and poorly in other countries.•The novel theory of information aggregation in prices when traders face cognitive costs of information processing predicts that weak forward guidance can amplify market responses to macroeconomic news.•Since Walrasian financial markets perform no allocative role in New Keynesian models, central bank actions which impede the aggregation of macroeconomic information in market prices could stabilize the economy and enhance private welfare.
Ehrmann et al. contains very useful international evidence on the efficacy of forward guidance at anchoring expectations of future policy rates at the ELB. The authors give one finding particular attention, that short-term time-consistent forward guidance raises the responses of expected future policy rates to macroeconomic data surprises. I argue that this empirical result should be interpreted with caution. Nevertheless, the paper’s development of a novel theoretical explanation for it based on financial market prices’ imperfect information aggregation merits the reader’s attention. I conjecture that such “imperfections” are welfare improving in standard New Keynesian models.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A large output gap accompanied by stable inflation close to its target calls for further monetary accommodation, but the zero lower bound on interest rates has robbed the Federal Open Market ...Committee (FOMC) of the usual tool for its provision. We examine how public statements of FOMC intentions—forward guidance—can substitute for lower rates at the zero bound. We distinguish between Odyssean forward guidance, which publicly commits the FOMC to a future action, and Delphic forward guidance, which merely forecasts macroeconomic performance and likely monetary policy actions. Others have shown how forward guidance that commits the central bank to keeping rates at zero for longer than conditions would otherwise warrant can provide monetary easing, if the public trusts it. We empirically characterize the responses of asset prices and private macroeconomic forecasts to FOMC forward guidance, both before and since the recent financial crisis. Our results show that the FOMC has extensive experience successfully telegraphing its intended adjustments to evolving conditions, so communication difficulties do not present an insurmountable barrier to Odyssean forward guidance. Using an estimated dynamic stochastic general equilibrium model, we investigate how pairing such guidance with bright-line rules for launching rate increases can mitigate risks to the Federal Reserve's price stability mandate.
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BFBNIB, CEKLJ, INZLJ, IZUM, KILJ, NMLJ, NUK, ODKLJ, PILJ, PNG, SAZU, UL, UM, UPUK, ZRSKP
Liquidity Constraints of the Middle Class Campbell, Jeffrey R.; Hercowitz, Zvi
American economic journal. Economic policy,
08/2019, Volume:
11, Issue:
3
Journal Article
Peer reviewed
Open access
Existing evidence from US middle class households shows that their MPCs out of tax rebates greatly exceed the PIH’s prediction and are weakly related to their liquid assets. The standard ...precautionary-saving model predicts the first fact but counterfactually requires MPCs to decrease with liquid wealth. Evidence from the Survey of Consumer Finances indicates widespread saving in anticipation of major expenditures like home purchases and college education. Adding such savings to the standard precautionary-saving model allows it to generate realistic MPCs for households with liquid wealth: the approaching expenditure simultaneously motivates asset accumulation and raises MPCs by shortening the effective planning horizon.
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BFBNIB, CEKLJ, NMLJ, NUK, PNG, UL, UM, UPUK
The International Society of Sports Nutrition (ISSN) provides an objective and critical review related to the intake of protein for healthy, exercising individuals. Based on the current available ...literature, the position of the Society is as follows:An acute exercise stimulus, particularly resistance exercise, and protein ingestion both stimulate muscle protein synthesis (MPS) and are synergistic when protein consumption occurs before or after resistance exercise.For building muscle mass and for maintaining muscle mass through a positive muscle protein balance, an overall daily protein intake in the range of 1.4-2.0 g protein/kg body weight/day (g/kg/d) is sufficient for most exercising individuals, a value that falls in line within the Acceptable Macronutrient Distribution Range published by the Institute of Medicine for protein.Higher protein intakes (2.3-3.1 g/kg/d) may be needed to maximize the retention of lean body mass in resistance-trained subjects during hypocaloric periods.There is novel evidence that suggests higher protein intakes (>3.0 g/kg/d) may have positive effects on body composition in resistance-trained individuals (i.e., promote loss of fat mass).Recommendations regarding the optimal protein intake per serving for athletes to maximize MPS are mixed and are dependent upon age and recent resistance exercise stimuli. General recommendations are 0.25 g of a high-quality protein per kg of body weight, or an absolute dose of 20-40 g.Acute protein doses should strive to contain 700-3000 mg of leucine and/or a higher relative leucine content, in addition to a balanced array of the essential amino acids (EAAs).These protein doses should ideally be evenly distributed, every 3-4 h, across the day.The optimal time period during which to ingest protein is likely a matter of individual tolerance, since benefits are derived from pre- or post-workout ingestion; however, the anabolic effect of exercise is long-lasting (at least 24 h), but likely diminishes with increasing time post-exercise.While it is possible for physically active individuals to obtain their daily protein requirements through the consumption of whole foods, supplementation is a practical way of ensuring intake of adequate protein quality and quantity, while minimizing caloric intake, particularly for athletes who typically complete high volumes of training. Rapidly digested proteins that contain high proportions of essential amino acids (EAAs) and adequate leucine, are most effective in stimulating MPS. Different types and quality of protein can affect amino acid bioavailability following protein supplementation. Athletes should consider focusing on whole food sources of protein that contain all of the EAAs (i.e., it is the EAAs that are required to stimulate MPS). Endurance athletes should focus on achieving adequate carbohydrate intake to promote optimal performance; the addition of protein may help to offset muscle damage and promote recovery. Pre-sleep casein protein intake (30-40 g) provides increases in overnight MPS and metabolic rate without influencing lipolysis.
The role of immune-oncologic mechanisms of racial disparities in prostate cancer remains understudied. Limited research exists to evaluate the molecular underpinnings of immune differences in African ...American men (AAM) and European American men (EAM) prostate tumor microenvironment (TME).
A total of 1,173 radiation-naïve radical prostatectomy samples with whole transcriptome data from the Decipher GRID registry were used. Transcriptomic expressions of 1,260 immune-specific genes were selected to assess immune-oncologic differences between AAM and EAM prostate tumors. Race-specific differential expression of genes was assessed using a rank test, and intergene correlational matrix and gene set enrichment was used for pathway analysis.
AAM prostate tumors have significant enrichment of major immune-oncologic pathways, including proinflammatory cytokines, IFNα, IFNγ, TNFα signaling, ILs, and epithelial-mesenchymal transition. AAM TME has higher total immune content score (ICS
) compared with 0 (37.8% vs. 21.9%,
= 0.003). AAM tumors also have lower DNA damage repair and are genomically radiosensitive as compared with EAM.
(IFN-inducible transmembrane protein 3) was one of the major proinflammatory genes overexpressed in AAM that predicted increased risk of biochemical recurrence selectively for AAM in both discovery HR
= 2.30; 95% confidence interval (CI), 1.21-4.34;
= 0.01 and validation (HR
= 2.42; 95% CI, 1.52-3.86;
= 0.0001) but not in EAM.
Prostate tumors of AAM manifest a unique immune repertoire and have significant enrichment of proinflammatory immune pathways that are associated with poorer outcomes. Observed immune-oncologic differences can aid in a genomically adaptive approach to treating prostate cancer in AAM.
Structural variations of DNA greater than 1 kilobase in size account for most bases that vary among human genomes, but are still relatively under-ascertained. Here we use tiling oligonucleotide ...microarrays, comprising 42 million probes, to generate a comprehensive map of 11,700 copy number variations (CNVs) greater than 443 base pairs, of which most (8,599) have been validated independently. For 4,978 of these CNVs, we generated reference genotypes from 450 individuals of European, African or East Asian ancestry. The predominant mutational mechanisms differ among CNV size classes. Retrotransposition has duplicated and inserted some coding and non-coding DNA segments randomly around the genome. Furthermore, by correlation with known trait-associated single nucleotide polymorphisms (SNPs), we identified 30 loci with CNVs that are candidates for influencing disease susceptibility. Despite this, having assessed the completeness of our map and the patterns of linkage disequilibrium between CNVs and SNPs, we conclude that, for complex traits, the heritability void left by genome-wide association studies will not be accounted for by common CNVs.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This chapter studies the effects of FOMC forward guidance. We begin by using high-frequency identification and direct measures of FOMC private information to show that puzzling responses of ...private-sector forecasts to movements in federal funds futures rates on FOMC announcement days can be attributed entirely to Delphic forward guidance. However, a large fraction of futures rates’ variability on announcement days remains unexplained, leaving open the possibility that the FOMC has successfully communicated Odyssean guidance. We then examine whether the FOMC used Odyssean guidance to improve macroeconomic outcomes since the financial crisis. To this end we usean estimated medium-scale New Keynesian model to perform a counterfactual experiment for the period 2009:Q1–2014:Q4, in which we assume the FOMC did not employ any Odyssean guidance and instead followed its reaction function from before the crisis as closely as possible while respecting the effective lower bound. We find that a purely rule-based policy would have delivered a shallower recession and kept inflation closer to target in the years immediately following the crisis than FOMC forward guidance did in practice. However, starting toward the end of 2011, after the Fed’s introduction of “calendar-based” communications, the FOMC’s Odyssean guidance appears to have boosted real activity and moved inflation closer to target. We show that our results do not reflect Del Negro, Giannoni, and Patterson’s (2015) forward-guidance puzzle.
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BFBNIB, INZLJ, NMLJ, NUK, PNG, UL, UM, UPUK, ZRSKP
To characterize the demographic and clinical features of pediatric severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) syndromes and identify admission variables predictive of disease ...severity.
We conducted a multicenter, retrospective, and prospective study of pediatric patients hospitalized with acute SARS-CoV-2 infections and multisystem inflammatory syndrome in children (MIS-C) at 8 sites in New York, New Jersey, and Connecticut.
We identified 281 hospitalized patients with SARS-CoV-2 infections and divided them into 3 groups based on clinical features. Overall, 143 (51%) had respiratory disease, 69 (25%) had MIS-C, and 69 (25%) had other manifestations including gastrointestinal illness or fever. Patients with MIS-C were more likely to identify as non-Hispanic black compared with patients with respiratory disease (35% vs 18%, P = .02). Seven patients (2%) died and 114 (41%) were admitted to the intensive care unit. In multivariable analyses, obesity (OR 3.39, 95% CI 1.26-9.10, P = .02) and hypoxia on admission (OR 4.01; 95% CI 1.14-14.15; P = .03) were predictive of severe respiratory disease. Lower absolute lymphocyte count (OR 8.33 per unit decrease in 109 cells/L, 95% CI 2.32-33.33, P = .001) and greater C-reactive protein (OR 1.06 per unit increase in mg/dL, 95% CI 1.01-1.12, P = .017) were predictive of severe MIS-C. Race/ethnicity or socioeconomic status were not predictive of disease severity.
We identified variables at the time of hospitalization that may help predict the development of severe SARS-CoV-2 disease manifestations in children and youth. These variables may have implications for future prognostic tools that inform hospital admission and clinical management.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The International Society of Sports Nutrition (ISSN) provides an objective and critical review regarding the timing of macronutrients in reference to healthy, exercising adults and in particular ...highly trained individuals on exercise performance and body composition. The following points summarize the position of the ISSN:Nutrient timing incorporates the use of methodical planning and eating of whole foods, fortified foods and dietary supplements. The timing of energy intake and the ratio of certain ingested macronutrients may enhance recovery and tissue repair, augment muscle protein synthesis (MPS), and improve mood states following high-volume or intense exercise.Endogenous glycogen stores are maximized by following a high-carbohydrate diet (8-12 g of carbohydrate/kg/day g/kg/day); moreover, these stores are depleted most by high volume exercise.If rapid restoration of glycogen is required (< 4 h of recovery time) then the following strategies should be considered:aggressive carbohydrate refeeding (1.2 g/kg/h) with a preference towards carbohydrate sources that have a high (> 70) glycemic indexthe addition of caffeine (3-8 mg/kg)combining carbohydrates (0.8 g/kg/h) with protein (0.2-0.4 g/kg/h) Extended (> 60 min) bouts of high intensity (> 70% VO
max) exercise challenge fuel supply and fluid regulation, thus carbohydrate should be consumed at a rate of ~30-60 g of carbohydrate/h in a 6-8% carbohydrate-electrolyte solution (6-12 fluid ounces) every 10-15 min throughout the entire exercise bout, particularly in those exercise bouts that span beyond 70 min. When carbohydrate delivery is inadequate, adding protein may help increase performance, ameliorate muscle damage, promote euglycemia and facilitate glycogen re-synthesis.Carbohydrate ingestion throughout resistance exercise (e.g., 3-6 sets of 8-12 repetition maximum RM using multiple exercises targeting all major muscle groups) has been shown to promote euglycemia and higher glycogen stores. Consuming carbohydrate solely or in combination with protein during resistance exercise increases muscle glycogen stores, ameliorates muscle damage, and facilitates greater acute and chronic training adaptations.Meeting the total daily intake of protein, preferably with evenly spaced protein feedings (approximately every 3 h during the day), should be viewed as a primary area of emphasis for exercising individuals.Ingestion of essential amino acids (EAA; approximately 10 g)either in free form or as part of a protein bolus of approximately 20-40 g has been shown to maximally stimulate muscle protein synthesis (MPS).Pre- and/or post-exercise nutritional interventions (carbohydrate + protein or protein alone) may operate as an effective strategy to support increases in strength and improvements in body composition. However, the size and timing of a pre-exercise meal may impact the extent to which post-exercise protein feeding is required.Post-exercise ingestion (immediately to 2-h post) of high-quality protein sources stimulates robust increases in MPS.In non-exercising scenarios, changing the frequency of meals has shown limited impact on weight loss and body composition, with stronger evidence to indicate meal frequency can favorably improve appetite and satiety. More research is needed to determine the influence of combining an exercise program with altered meal frequencies on weight loss and body composition with preliminary research indicating a potential benefit.Ingesting a 20-40 g protein dose (0.25-0.40 g/kg body mass/dose) of a high-quality source every three to 4 h appears to most favorably affect MPS rates when compared to other dietary patterns and is associated with improved body composition and performance outcomes.Consuming casein protein (~ 30-40 g) prior to sleep can acutely increase MPS and metabolic rate throughout the night without influencing lipolysis.
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