The Stationery Distribution of Wealth with Random Shocks

A convergence model with wealth accumulation subject to i.i.d. random shocks is examined. The transfer function shows what k_{t+1} - wealth at t+1 - would be, given k_t, with no shock: It has a positive slope, but its concavity/convexity is indeterminate. The stationary distribution of wealth satisfies a Fredholm integral equation. This distribution can be examined by direct analysis of the wealth-accumulation stochastic process and via the Fredholm equation. The analysis resembles some econometric theory of time series. Economic theory forces consideration of a broad range of cases, including some which violate B-convergence. "Twin peaks" in the stationary distribution cannot be excluded.Convergence, stochastic process, wealth distribution

Macaque cardiac physiology is sensitive to the valence of passively viewed sensory stimuli.

Autonomic nervous system activity is an important component of affective experience. We demonstrate in the rhesus monkey that both the sympathetic and parasympathetic branches of the autonomic nervous system respond differentially to the affective valence of passively viewed video stimuli. We recorded cardiac impedance and an electrocardiogram while adult macaques watched a series of 300 30-second videos that varied in their affective content. We found that sympathetic activity (as measured by cardiac pre-ejection period) increased and parasympathetic activity (as measured by respiratory sinus arrhythmia) decreased as video content changes from positive to negative. These findings parallel the relationship between autonomic nervous system responsivity and valence of stimuli in humans. Given the relationship between human cardiac physiology and affective processing, these findings suggest that macaque cardiac physiology may be an index of affect in nonverbal animals

Twitter reciprocal reply networks exhibit assortativity with respect to happiness

The advent of social media has provided an extraordinary, if imperfect, 'big data' window into the form and evolution of social networks. Based on nearly 40 million message pairs posted to Twitter between September 2008 and February 2009, we construct and examine the revealed social network structure and dynamics over the time scales of days, weeks, and months. At the level of user behavior, we employ our recently developed hedonometric analysis methods to investigate patterns of sentiment expression. We find users' average happiness scores to be positively and significantly correlated with those of users one, two, and three links away. We strengthen our analysis by proposing and using a null model to test the effect of network topology on the assortativity of happiness. We also find evidence that more well connected users write happier status updates, with a transition occurring around Dunbar's number. More generally, our work provides evidence of a social sub-network structure within Twitter and raises several methodological points of interest with regard to social network reconstructions.Comment: 22 pages, 21 figures, 5 tables, In press at the Journal of Computational Scienc

A Cross-Sectional Study Comparing the Frequency of Drug Interactions After Adding Simeprevir- or Sofosbuvir-Containing Therapy to Medication Profiles of Hepatitis C Monoinfected Patients.

INTRODUCTION:This study compares the expected occurrence of contraindicated drug-drug interactions (XDDIs) when simeprevir (SIM)- or sofosbuvir (SOF)-containing therapy is added to medication profiles of patients with hepatitis C (HCV) monoinfection to quantify, in relative terms, the population-based risk of XDDIs. Second, this study identified the predictors of XDDIs when HCV therapies are added to medication profiles. METHODS:A cross-sectional study was performed among Veterans' Affairs patients. Inclusion criteria were: (1) age ≥18 years, (2) HCV infection, and (3) availability of a medication list. Patients with human immunodeficiency virus were excluded. Demographics, comorbidities, year of HCV diagnosis, and most recent medication list were collected from medical records. The primary outcome was the presence of XDDIs involving HCV therapy and the medications in the patient's home medication list after the addition of either SIM- or SOF-containing regimens. To define XDDIs, Lexi-Interact drug interaction software was used. RESULTS:4,251 patients were included. The prevalence of XDDIs involving SIM- or SOF-containing therapy were 12.6% and 4.7% (p < 0.001), respectively. In multivariable analyses examining the predictors of XDDIs involving SIM-containing therapy, the only medication-related predictor was use of ≥6 home medications (odds ratio OR 4.58, 95% confidence interval CI 3.54-5.20, p < 0.001). Similarly, use of ≥6 home medications was also the only variable associated with an increased probability of XDDI involving SOF-containing therapy (OR 3.83, 95% CI 2.57-5.70, p < 0.001). CONCLUSIONS:Sofosbuvir-containing therapy had a lower frequency of XDDIs than SIM-containing therapy. Polypharmacy with various classes of home medications predicted XDDIs involving SIM- or SOF-containing therapy

Temporal patterns of happiness and information in a global social network: Hedonometrics and Twitter

Individual happiness is a fundamental societal metric. Normally measured through self-report, happiness has often been indirectly characterized and overshadowed by more readily quantifiable economic indicators such as gross domestic product. Here, we examine expressions made on the online, global microblog and social networking service Twitter, uncovering and explaining temporal variations in happiness and information levels over timescales ranging from hours to years. Our data set comprises over 46 billion words contained in nearly 4.6 billion expressions posted over a 33 month span by over 63 million unique users. In measuring happiness, we use a real-time, remote-sensing, non-invasive, text-based approach---a kind of hedonometer. In building our metric, made available with this paper, we conducted a survey to obtain happiness evaluations of over 10,000 individual words, representing a tenfold size improvement over similar existing word sets. Rather than being ad hoc, our word list is chosen solely by frequency of usage and we show how a highly robust metric can be constructed and defended.Comment: 27 pages, 17 figures, 3 tables. Supplementary Information: 1 table, 52 figure

Acute Responses to High Intensity Interval Exercise and Moderate Aerobic Exercise on Anaerobically and Aerobically Trained Athletes

High Intensity Interval Training (HIIT) is emerging as the popular method of training recently for its ability to deliver an exercise that still elicits almost the same health benefits, when compared to traditional methods of training. Those who are trained possess higher lactate thresholds than those who are not trained. However, there is little research on males whom are trained as anaerobically or aerobically, and their differences on lactate or blood glucose recovery. PURPOSE: The purpose of this study is to compare the acute effects of high intensity interval exercise and moderate aerobic exercise on lactic acid and blood glucose levels on athletes who are either anaerobically trained or aerobically trained. METHODS: Males (20± 2.774) of average cardiorespiratory fitness (VO2max =35 ±5.95 ) participated in a high intensity interval exercise (HIIE) and a moderate aerobic trial in a balanced cross-over design in which the subject was randomized and assessed for changes in blood lactate levels and glucose levels during exercise. The HIIE is a 4 x 4 trial in which the subject pedaled on a cycle for four intervals of 4 minutes at 90-95% of maximal aerobic capacity (VO2max), interspersed with 3 minutes of active recovery at 60% VO2max. The subjects were assessed for blood lactate and blood glucose via finger stick prior to exercise, at minute 4, 13, 24, 32 and every 10 minutes post-exercise up to 30 minutes following the cessation of the exercise bout. The subjects also participated in a moderate aerobic trial at 60% of VO2max. The subjects were assessed for blood lactate and blood glucose via finger stick however time points are varied per subject due to variations in total work outputs. RESULTS: The main effect for recovery was not significant in lactate when comparing training status across both HIIE/Mod (Ana=5.7± 4.3, Aer=8.3± 4.7) (p=0.3470). The main effect for glucose was also not significant when comparing training status across both HIIE/Mod (Ana=93± 12.5, Aer=102.7± 12.5) (p=0.2350). The main effect for lactate when comparing training (Aer/Ana) across intensity (HIIE/Mod) was not significant (AnaHi=4.6± 1.2, AnaMod=6.9± 8.2, AerHi=5.7± 1.3, AerMod=10.9± 9.0) (p=0.5620). The main effect for glucose when comparing training (Aer/Ana) across intensity (HIIE/Mod) was also not significant (AnaGlucHi=93.5± 20.1, AnaGlucMod=92.5± 13.6, AerGlucHi=112.8± 20.1, AerGlucMod=92.6± 13.6) (p=0.2100) CONCLUSIONS: Although lactate nor glucose were statistically significant in this study, when comparing the values, anaerobically trained males buffered lactic acid more efficiently than those who are aerobically trained. This might suggest that those whom are anaerobically trained possess higher lactate threshold than those who are aerobically trained

The Effect of a Commercially Available Pre-Workout Supplement (The Bracket™) on Wingate Anaerobic Cycle Test Performance in Athletic Females

The Bracket™ is a proprietary blend, pre-workout supplement whose primary active ingredients consists mostly of a mixture of creatine, B-complex vitamins, and a glycerol/taurine combination. It has been third party tested for ingredient accuracy, and is also certified by NSF, meaning that it is certified for sports consumption. Previous research has been done on the ingredients within the supplement utilizing male demographics. However, there is limited research done on the pre-workout supplement as a whole. The little research done has showed no increases in any variables such as power output (relative/absolute) and/or rate of fatigue. Very little research has been done utilizing a female population, let alone athletic females. PURPOSE: To examine the effect of a commercially available pre-workout supplement (The Bracket™), in athletic females, on absolute peak power (APP), absolute mean power (AMP), relative peak power (RPP), relative mean power (RMP), rate of fatigue (FTR), absolute total work (ATW), and relative total work (RTW) utilizing the Wingate Anaerobic Cycle Test (WACT), a 30-s supra maximal exercise protocol. METHODS: Thirteen athletic females, ages 18-30, with no prior hamstrings or quadriceps injuries within the last years were recruited. All subjects underwent three experimental trials [treatment (TRT, supplement with Gatorade®), placebo (PLC, Gatorade®), and a control (CON, water)] in a single blind balanced crossover design. During the trials the subjects had to ingest one of the three liquids in an 8 ounce serving thirty minutes prior to engaging in the WACT. Each trial was performed approximately one week apart. The differences in the dependent variables between treatments were analyzed using an ANOVA (0 between, 1 within), α=0.05. RESULTS: No significant difference between trials were seen for APP (TRT=715 ± 126 W; PLC=71 6± 125 W; CON=696 ± 147 W) (p=0.2940), AMP (TRT=446 ± 94 W; PLC=436 ± 85 W; CON=441 ± 91 W)(p=0.3930), RPP (TRT=11.6 ±. 1.4 W·kg-1; PLC=11.6 ±. 1.5 W·kg-1; CON=11.3 ±. 1.5 W·kg-1)(p=0.2280), RMP (TRT=7.3 ±. 1.4 W·kg-1; PLC=7.1 ± 1.1 W·kg-1; CON=7.2 ±. 1.3 W·kg-1)(p=0.3920), FTR (TRT=62 ± 13%; PLC=61 ± 11%; CON=59 ± 11%) (p=0.1920), ATW (TRT=13368 ± 2798 J; PLC=13066 ± 2550 J; CON=13246 ± 2749 J)(p=0.4100), or RTW (TRT=218 ± 42 J·kg-1; PLC=212 ± 33 J·kg-1; CON= 215 ± 38 J·kg-1)(p=0.4080). CONCLUSION: Ingestion of (The Bracket™) prior to exercise does not affect performance on the WACT in athletic females

The Acute Effects of Self-Myofascial Release on Range of Motion and Fatigue Rate in the Lower Extremities

There has been a growing popularity in a technique similar to a massage that is easily accessible known as self-myofascial release, or more commonly as “foam rolling”. While research has been conducted to examine the effects on a smooth foam roller, little research has been conducted regarding a more aggressive form of deep tissue self-myofascial release on muscular strength and fatigability. PURPOSE: To examine the acute effect of deep tissue self-myofascial release on hip range of motion and fatigue rate of the quadriceps in uninjured individuals. METHODS: Nineteen males, ages 20-35, with no prior knee surgery/injury on their preferred leg regardless of current functional status were recruited. Subjects were allowed familiarity trials for goniometry of hip flexion/extension, self-myofascial release, and the isokinetic strength/fatigability test prior to exercise testing. All subjects underwent three experimental trials [self-myofascial release (SMR), static stretching (STS), no additional warm-up control (CON)] in a balanced crossover design. During the treatment trials, subjects were required to perform a 10 minute warm-up on a stationary rate independent cycle ergometer (50 W) followed by one of the treatments applied to the hamstrings and quadriceps of the preferred leg; SMR (1 set; 2 min), STS (4 sets; 30 secs). Subjects were required to perform the Thorstensson test, using a single-chair isokinetic dynamometer, which consisted of 50 voluntary maximal isokinetic leg extensions on their preferred leg where the rate of force production was controlled as 180°.sec-1. Measurement of hip flexion (HF) and extension (HE), absolute peak quadriceps force production (AF), relative peak quadriceps force production (RF), quadriceps fatigue rate (FR), and perceived local leg fatigue (PF) were recorded. One-way ANOVA with repeated measures was used to analyze for differences between trials (STS, SMR, CON), except for FR where a Friedman ANOVA was used, α=0.05. RESULTS: HF did differ significantly between the treatments (p\u3c0.05) where SMR (113.7±4.8°) and STS (114.7±4.9°) \u3e CON (106.2±5.0°). The treatments also differed significantly (p\u3c0.05) in HE, where SMR (19.7±3.3°) and STS (18.2±4.3°) \u3e CON (13.2±3.6°). AF did not differ significantly (p\u3e0.05) between the treatments (SMR=175.2±32.1 Nm, STS=180.9±35.6 Nm, CON=177.2±38.3 Nm), nor did RF (SMR=1.9±0.4 Nm/kg, STS=1.9±0.4 Nm/kg, CON=1.9±0.4). FR also did not differ (p\u3e0.05) between treatments (SMR=59.7±9.4%, STS=61.3±11.0%, CON=61.5±8.8%). PF was seen to be more frequently greater with most subjects in CON, but there were no significant difference (p\u3e0.05) between trials. CONCLUSION: While SMR had no effect on muscular strength and fatigability, SMR did have similar significant effect as static stretching on hip range of motion