Early-Morning and Late-Night Maximal Runs: Metabolic and Perceived Exertion Outcomes

People may exercise at the ends of their day to fit activity into their schedule; the purpose of this investigation was to determine if metabolic or perceived exertion outcomes differed between maximal runs early in the morning and late at night. After consuming a standardized, glucose drink, thirteen recreationally active individuals completed an early-morning and a late-night run on the treadmill while researchers measured metabolic (aerobic capacity and substrate usage) and perceived exertion outcomes. Point of application #1: Aerobic capacity (maximal consumption of oxygen) and the usage of fat as a fuel to support energy production during exercise were similar between runs. Point of application #2: Maximal perceived exertion (Borg’s 6-20) was similar during early-morning and late-night runs. Point of application #3: While research indicates that people may prefer activity in the morning or evening, and this might impact metabolic responses to the exercise bout, most of our participants (n=8) identified with no preference for exercising in the early-morning or late-night. Key Words: glucose; CHO shake; VO2max; fat oxidation; effor

Endothelial function and arterial stiffness in young adults with histories of chronic resistance activity

Endothelial dysfunction and arterial stiffness indicate vessel damage and are detectable before overt cardiovascular disease. Chronic cardiorespiratory endurance activity improves arterial endothelial function and stiffness. The influence of chronic resistance activity on these variables is less definitive and thus deserves attention. The primary aim of this investigation was to determine if endothelial dysfunction and arterial stiffness were present in apparently healthy young adults who chronically engage in resistance activity with minimal cardiorespiratory endurance activity. Investigators measured endothelial function as LnRHI and arterial stiffness as AI@75 using the EndoPAT-2000. Investigators measured upper-body muscular strength using a standardized one-repetition maximum (1-RM) bench press. The LnRHI and AI@75 between males and females were compared via an independent-samples t-test and Mann-Whitney U test, respectively. Correlations between 1-RM, bench press to body weight ratio, LnRHI, and AI@75 were evaluated via Pearson’s correlation. Males’ LnRHI was abnormal according to manufacturer standards and lower than females’ (p = .005), but AI@75 was normal and similar for both sexes (p = .22). The 1-RM and bench press to body weight ratio correlated negatively with LnRHI (p = .03 and p = .01, respectively). The bench press to body weight ratio correlated negatively with AI@75 (p = .03), and percentage body fat correlated positively with the AI@75 (p = .003). Young adult males with considerable upper-body muscular strength due to chronic resistance activity, who complete minimal cardiorespiratory endurance activity, appear to have detectable signs of early endothelial dysfunction

Demonstrable Evidence of Beneficial Physical Outcomes from University Physical Education Activity Courses

Introduction: Engagement in physical activity (PA) is often dramatically reduced during the transition from high school into college. There appears to be more stability in PA patterns during the transition from college into post-graduate life. Consequently, researchers have highlighted the years in higher education as pivotal for shaping lasting PA habits. Sadly, there is a widespread lack of evidence regarding the outcomes from physical education activity courses (PEAC) offered on campuses of higher education. Thus, their overall value lacks validation. The purpose of this work was to offer evidence of outcomes from engagement in a single, semester-long university PEAC class. Methods: Students were recruited from a variety of classes. There were no directions provided to the instructors of the courses. For grouping, classes were categorized as aerobic- (aerobics, jogging, and walking) or sport-activity (badminton, pickle ball, self-defense, strength training, and ultimate frisbee). Students in the aerobic-activity arm were randomized to aerobic testing where they underwent a submaximal treadmill protocol and grip strength (GS) testing or body composition testing (air displacement plethysmography) and GS. Those in the sport-activity arm underwent vertical jump and GS testing. Students reported to the human performance lab in the first two and final two weeks of the semester. Paired t-tests were conducted to identify differences in pre-post outcomes. Values were carried forward, not dropped, when a subject failed to return at post-test. Results: A total of 46 students (age = 21.7 ± 4.1) were randomized into the aerobic (n=25; m/f = 11/14) or body composition arms (n=21; m/f = 7/14). Additionally, 45 students (age = 20.8 ± 3.2; m/f = 23/22) from sport-activity classes were enrolled. Participation in aerobic-activity classes resulted in improvements in estimated maximal aerobic ability (p = 0.030; 42.9 ± 9.9 vs. 44.6 ± 10.1). Participation also resulted in increases in GS for those allocated to both the aerobic (p = 0.010; 56.4 ± 21.5 vs. 60.3 ± 22.3) and body composition (p = 0.022; 54.1 ± 22.1 vs. 58.1 ± 24.6) arms. Participation did not result in changes in body composition (p = 0.817; 24.7 ± 8.5 vs. 24.6 ± 7.4) despite a near-significant increase in weight (p = 0.057; 152.7 ± 38.5 vs. 154.5 ± 37.7). Participation in sport-activity classes resulted in an improvement in vertical jump (p = 0.007; 18.2 ± 6.1 vs. 18.9 ± 6.0) and GS (p = 0.002; 65.3 ± 25.6 vs. 70.0 ± 27.8). Discussion: An important first step in rebutting challenges about the credibility and worthiness of PEAC offerings is evidencing beneficial outcomes. These results represent simple, but important, markers of change. Additional demonstrable evidence is needed to ascertain elements such as what outcomes are achievable, what classes are most effective classes, and what components from class support lasting change

Survey Responses From “Wellness for Life” Classes: Overall Value and Barriers, Motivators, and Motives Towards Physical Activity

Introduction: Skill-based sport activity classes were the historical trend, but greater numbers of higher education institutions now offer courses that encompass “wellness for life” concepts. The goal of these offerings is to guide students in the development of knowledge, skills, and behaviors to adopt and maintain healthful behaviors. There is a need to amass evidence of the outcomes arising from engagement in these classes. Purpose: The purpose of this work was to document outcomes from participation in a single, semester-long, university wellness for life class. Methods: Students were recruited from courses at two universities. Survey responses were collected in the first two and final two weeks of class. The survey items included identification of: engagement in regular physical activity (PA), perceptions about PA (“view of self as an exerciser”, “contentment with current PA level”, among others), and barriers, motivators, and motives towards PA. There were no intervention suggestions provided to instructors. Results: A total of 173 students (m/f/not identified = 51/118/4; age 19.6 ± 1.4) participated. When questioned, many students identified as being an “exerciser.” Some perceived “no need to change their program” (n=37) but most “wanted more regular exercise” (n=88). A lesser number of students identified as being a “non-exerciser.” Most all “wanted more regular exercise” (n=46), but two had “no desire to start a program.” At post-test, the respective numbers were: 37, 95, 41, and 3. Numbers did not always align due to incomplete survey responses. The perceived value of the class to current and future health, rated on a scale from 0 (no impact)-100 (most influential), improved pre-post class (p \u3c 0.001) from 61.7 (±24.5) to 67.8 (±23.5). The top barrier, motivator, and motive at pre-test were: “I need to do better at managing my time to exercise more often,” “If I better organized my time or schedule I could exercise more,” and “I get pleasure or enjoy sports so I exercise,” respectively. There was shuffling among the top choices from pre- to post-test, but the top barrier remained the same. The top motivator became, “If I had more time I would exercise more,” and the top motive became, “I feel less stress after I exercise.” Discussion: Evidenced by the pre-post responses, students feel that wellness for life classes have some benefit and that perception improves after experiencing the class. There appears to be consistency in those who view themselves as “exercisers” and “non-exercisers,” which might represent a precarious situation. There is constancy in the primary barrier to exercise – the socially acceptable answer – time. It is obvious that time management is a critical element for inclusion in these classes. Students may also benefit more if instructors would offer insight on the use of motivators and motives in overcoming personal barriers

The NANOGrav 11-Year Data Set: Limits on Gravitational Waves from Individual Supermassive Black Hole Binaries

Observations indicate that nearly all galaxies contain supermassive black holes (SMBHs) at their centers. When galaxies merge, their component black holes form SMBH binaries (SMBHBs), which emit low-frequency gravitational waves (GWs) that can be detected by pulsar timing arrays (PTAs). We have searched the recently-released North American Nanohertz Observatory for Gravitational Waves (NANOGrav) 11-year data set for GWs from individual SMBHBs in circular orbits. As we did not find strong evidence for GWs in our data, we placed 95\% upper limits on the strength of GWs from such sources as a function of GW frequency and sky location. We placed a sky-averaged upper limit on the GW strain of $h_0 < 7.3(3) \times 10^{-15}$ at $f_\mathrm{gw}= 8$ nHz. We also developed a technique to determine the significance of a particular signal in each pulsar using ``dropout' parameters as a way of identifying spurious signals in measurements from individual pulsars. We used our upper limits on the GW strain to place lower limits on the distances to individual SMBHBs. At the most-sensitive sky location, we ruled out SMBHBs emitting GWs with $f_\mathrm{gw}= 8$ nHz within 120 Mpc for $\mathcal{M} = 10^9 \, M_\odot$, and within 5.5 Gpc for $\mathcal{M} = 10^{10} \, M_\odot$. We also determined that there are no SMBHBs with $\mathcal{M} > 1.6 \times 10^9 \, M_\odot$ emitting GWs in the Virgo Cluster. Finally, we estimated the number of potentially detectable sources given our current strain upper limits based on galaxies in Two Micron All-Sky Survey (2MASS) and merger rates from the Illustris cosmological simulation project. Only 34 out of 75,000 realizations of the local Universe contained a detectable source, from which we concluded it was unsurprising that we did not detect any individual sources given our current sensitivity to GWs.Comment: 10 pages, 11 figures. Accepted by Astrophysical Journal. Please send any comments/questions to S. J. Vigeland ([email protected]

The chemerin knockout rat reveals chemerin dependence in female, but not male, experimental hypertension

Measures of the adipokine chemerin are elevated in multiple cardiovascular diseases, including hypertension, but little mechanistic work has been done to implicate chemerin as being causative in such diseases. The chemerin knockout (KO) rat was created to test the hypothesis that removal of chemerin would reduce pressure in the normal and hypertensive state. Western analyses confirmed loss of chemerin in the plasma and tissues of the KO vs. wild‐type (WT) rats. Chemerin concentration in plasma and tissues was lower in WT females than in WT males, as determined by Western analysis. Conscious male and female KO rats had modest differences in baseline measures vs. the WT that included systolic, diastolic, mean arterial and pulse pressures, and heart rate, all measured telemetrically. The mineralocorticoid deoxycorticosterone acetate (DOCA) and salt water, combined with uninephrectomy as a hypertensive stimulus, elevated mean and systolic blood pressures of the male KO higher than the male WT. By contrast, all pressures in the female KO were lower than their WT throughout DOCA‐salt treatment. These results revealed an unexpected sex difference in chemerin expression and the ability of chemerin to modify blood pressure in response to a hypertensive challenge.—Watts, S. W., Darios, E. S., Mullick, A. E., Garver, H., Saunders, T. L., Hughes, E. D., Filipiak, W. E., Zeidler, M. G., McMullen, N., Sinal, C. J., Kumar, R. K., Ferland, D. J., Fink, G. D. The chemerin knockout rat reveals chemerin dependence in female, but not male, experimental hypertension. FASEB J. 32, 6596–6614 (2018). www.fasebj.orgPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154357/1/fsb2fj201800479.pd

Chiang Kai-shek’s “secret deal” at Xian and the start of the Sino-Japanese War

Using newly available archives, particularly the diary and the presidential papers of Chiang Kai-shek, this article challenges the conventional interpretations of the Xian Incident (1936), in particular the widely held belief that the kidnapping of China’s leader Chiang by two rebellious generals forced him to form a united front with the Communist Party to confront Japanese aggression, and of the outbreak of the Sino-Japanese War 7 months later. It puts forth the interpretation that full-scale war between China and Japan was started not by Japan but by Chiang after a Japanese provocation, and the united front was only formed after Chiang ordered his best army units to attack Japanese forces in Shanghai in August 1937 turning it into the largest land battle after the First World War. It must be noted, however, that Japan acted provocatively and aggressively in a local incident outside Beijing a month earlier. Chiang decided on war not because he reached an agreement with the Chinese Communists to form a united front whilst a captive in Xian but because in Xian he received a signal from Josef Stalin that the Soviet Union would support him in a war with Japan. Chiang read Stalin right and the Soviet Union became the largest supplier of weapons to China in the first 4 years of China’s 8-year war with Japan. The hitherto unknown or “secret deal” Chiang made in Xian was an implicit one with Stalin, not with the Chinese Communist Party or its man on the spot Zhou Enlai

Multi-Messenger Gravitational Wave Searches with Pulsar Timing Arrays: Application to 3C66B Using the NANOGrav 11-year Data Set

When galaxies merge, the supermassive black holes in their centers may form binaries and, during the process of merger, emit low-frequency gravitational radiation in the process. In this paper we consider the galaxy 3C66B, which was used as the target of the first multi-messenger search for gravitational waves. Due to the observed periodicities present in the photometric and astrometric data of the source of the source, it has been theorized to contain a supermassive black hole binary. Its apparent 1.05-year orbital period would place the gravitational wave emission directly in the pulsar timing band. Since the first pulsar timing array study of 3C66B, revised models of the source have been published, and timing array sensitivities and techniques have improved dramatically. With these advances, we further constrain the chirp mass of the potential supermassive black hole binary in 3C66B to less than $(1.65\pm0.02) \times 10^9~{M_\odot}$ using data from the NANOGrav 11-year data set. This upper limit provides a factor of 1.6 improvement over previous limits, and a factor of 4.3 over the first search done. Nevertheless, the most recent orbital model for the source is still consistent with our limit from pulsar timing array data. In addition, we are able to quantify the improvement made by the inclusion of source properties gleaned from electromagnetic data to `blind' pulsar timing array searches. With these methods, it is apparent that it is not necessary to obtain exact a priori knowledge of the period of a binary to gain meaningful astrophysical inferences.Comment: 14 pages, 6 figures. Accepted by Ap

Photoionization of alkali and alkaline earth atoms: Na and Mg

Determinations of the photoionization cross sections of ground state magnesium atoms and excited state sodium atoms have been made over a wide wavelength range. The ground state measurement in magnesium was performed using synchrotron radiation from the uv ring at the National Synchrotron Light Source. Several autoionizing resonances were observed. The photoionization cross section of excited sodium atoms was determined by irradiating laser-produced Na(3p) with synchrotron light. In both cases, agreement with theory is excellent