Variability in energy expenditure is much greater in males than females

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Energy compensation and adiposity in humans

Acknowledgments The DLW database, which can be found at https://doubly-labelled-water-database.iaea.org/home, is hosted by the IAEA and generously supported by Taiyo Nippon Sanso and SERCON. We are grateful to the IAEA and these companies for their support and especially to Takashi Oono for his tremendous efforts at fundraising on our behalf. The authors also gratefully acknowledge funding from the Chinese Academy of Sciences (CAS 153E11KYSB20190045) to J.R.S. and the US National Science Foundation (BCS-1824466) awarded to H.P. The funders played no role in the content of this manuscript. We are grateful for the data submission of David Ludwig and Cara Ebbeling, and for the analysis by Steve Heymsfield of his own data indicating no change in FFM hydration with age in adults.Peer reviewedPublisher PD

Variation in human water turnover associated with environmental and lifestyle factors

Water is essential for survival, but one in three individuals worldwide (2.2 billion people) lacks access to safe drinking water. Water intake requirements largely reflect water turnover (WT), the water used by the body each day. We investigated the determinants of human WT in 5604 people from the ages of 8 days to 96 years from 23 countries using isotope-tracking (2H) methods. Age, body size, and composition were significantly associated with WT, as were physical activity, athletic status, pregnancy, socioeconomic status, and environmental characteristics (latitude, altitude, air temperature, and humidity). People who lived in countries with a low human development index (HDI) had higher WT than people in high-HDI countries. On the basis of this extensive dataset, we provide equations to predict human WT in relation to anthropometric, economic, and environmental factors.acceptedVersio

Greater male variability in daily energy expenditure develops through puberty

There is considerably greater variation in metabolic rates between men than between women, in terms of basal, activity and total (daily) energy expenditure (EE). One possible explanation is that EE is associated with male sexual characteristics (which are known to vary more than other traits) such as musculature and athletic capacity. Such traits might be predicted to be most prominent during periods of adolescence and young adulthood, when sexual behaviour develops and peaks. We tested this hypothesis on a large dataset by comparing the amount of male variation and female variation in total EE, activity EE and basal EE, at different life stages, along with several morphological traits: height, fat free mass and fat mass. Total EE, and to some degree also activity EE, exhibit considerable greater male variation (GMV) in young adults, and then a decrease in the degree of GMV in progressively older individuals. Arguably, basal EE, and also morphometrics, do not exhibit this pattern. These findings suggest that single male sexual characteristics may not exhibit peak GMV in young adulthood, however total and perhaps also activity EE, associated with many morphological and physiological traits combined, do exhibit GMV most prominently during the reproductive life stages

Greater Male Variability in Daily Energy Expenditure Develops Through Puberty

There is considerably greater variation in metabolic rates between men than between women, in terms of basal, activity and total (daily) energy expenditure (EE). One possible explanation is that EE is associated with male sexual characteristics (which are known to vary more than other traits) such as musculature and athletic capacity. Such traits might be predicted to be most prominent during periods of adolescence and young adulthood, when sexual behaviour develops and peaks. We tested this hypothesis on a large dataset by comparing the amount of male variation and female variation in total EE, activity EE and basal EE, at different life stages, along with several morphological traits: height, fat free mass and fat mass. Total EE, and to some degree also activity EE, exhibit considerable greater male variation (GMV) in young adults, and then a decreasing GMV in progressively older individuals. Arguably, basal EE, and also morphometrics, do not exhibit this pattern. These findings suggest that single male sexual characteristics may not exhibit peak GMV in young adulthood, however total and perhaps also activity EE, associated with many morphological and physiological traits combined, do exhibit GMV most prominently during the reproductive life stages

Greater male variability in daily energy expenditure develops through puberty

There is considerably greater variation in metabolic rates between men than between women, in terms of basal, activity and total (daily) energy expenditure (EE). One possible explanation is that EE is associated with male sexual characteristics (which are known to vary more than other traits) such as musculature and athletic capacity. Such traits might be predicted to be most prominent during periods of adolescence and young adulthood, when sexual behaviour develops and peaks. We tested this hypothesis on a large dataset by comparing the amount of male variation and female variation in total EE, activity EE and basal EE, at different life stages, along with several morphological traits: height, fat free mass and fat mass. Total EE, and to some degree also activity EE, exhibit considerable greater male variation (GMV) in young adults, and then a decrease in the degree of GMV in progressively older individuals. Arguably, basal EE, and also morphometrics, do not exhibit this pattern. These findings suggest that single male sexual characteristics may not exhibit peak GMV in young adulthood, however total and perhaps also activity EE, associated with many morphological and physiological traits combined, do exhibit GMV most prominently during the reproductive life stages

WiFi Hotspots for Reindeer Herding and other Delay-Tolerant Applications

Despite continuous advancements in mobile communication technologies, there are rural areas even in developed countries like Sweden that still lack basic forms of connectivity. Sweden’s arctic region suffer from a low cost effectiveness of mobile telecommunication infrastructures which results in a lack of cellular coverage in many areas. In response to these challenges, Tannak AB was founded by two Saami women who had their own solution for the reindeer herding industry. With Tannak’s telemetry network, reindeer are tracked with GPS-equipped collars and information is forwarded in-between base stations before transmitted through the regular cellular network. While reindeer inside these areas may now be tracked, reindeer herders still need Internet access to retrieve this information - which they in some places don’t have. This thesis explores how Tannak’s network could be further utilized to also provide limited connectivity and services to end users, primarily to allow access to tracking information directly form the network. The presented solution includes an interface to Tannak’s network in the form of portable WiFi hotspots, which would be hosted by mobile base stations in the network. The service of accessing tracking information is here implemented and tested between an Android device and a laptop controlling a WiFi module. A developed map based Android application allows viewing reindeer information both from the web and directly from the field network. Furthermore, introducing a power saving schedule specifically adapted to the delay-tolerant nature of the tracking network has shown to decrease hourly battery consumption of the WiFi module by 4/5 to merely 6.8 mAh. This is compared to not using the power schedule, while doing four transmissions per hour over the WiFi interface. The results indicate that the solution could be a valid approach as an end user interface to the tracking system. Based on the properties of the tracking network other possible applications are suggested to be included as well, one being the transmission of text messages to phones in the GSM network

INVESTERARES REAKTIONER PÅ SPELARÖVERGÅNGAR : En kvantitativ studie om hur spelarövergångar inom fotbollenpåverkar aktiepriset

Summorna som fotbollsklubbarna betalar för spelarförvärv har ökat avsevärt i modern tid. Inträdet av rika majoritetsägare med andra agendor än att vinstmaximera samt exponeringen sporten fått världen över har lett till att omsättningen nästan dubblerats mot för 10 år sedan. Incitamentet till att göra den här studien uppkom efter att övertid bevittnat de skenade transfersummorna och framför allt den ökade volymen av spelaövergångar. Med vetskap att några av de största klubbarna i världen också är börsnoterade började tankarna vandra mot hur investerare värderar dessa övergångar. Delar investerare den bilden av att förvärv inte alltid genomförs för den ekonomiska vinningens skull?Med dessa tankar kom författarna upp med följande problemformuleringar:Anser investerare att spelarövergångar är väsentlig information?Har investerares syn på spelarövergångar i europeiska börsnoterade fotbollsklubbar förändrats över tid?För att besvara dessa problemformuleringar har studien tillämpat en händelsestudie för att jämföra den förväntade avkastningen med den verkliga avkastningen efter att en spelarövergång inträffat. Den förväntade avkastningen har estimerats med hjälp av avkastningen det specifika aktieindexet haft på den börs där aktien finns noterad.Som alla kvantitativa studier som följer en deduktiv metod ligger en teori till grund som empiriskt ska undersökas. Genom den effektiva marknadshypotesen får vi en bild av vad som händer på marknaden då ny information blir tillgänglig. Genom att undersöka aktieavkastningen i samband med en spelarövergång bör därför ge en träffsäker förklaring på hur investerare värderar spelarövergångar.Vissa tendenser mellan avvikande avkastningar och övergångar har kunnat identifieras men, studien har inte kunnat presentera några statistiskt signifikanta avvikande avkastningar när det kommer till vare sig spelarköp eller spelarförsäljningar. Inte heller kan det sägas med någon statistisk säkerhet att investerare reagerar annorlunda på spelarövergångar idag än vad de tidigare gjor

Reliable and clinically applicable gait event classification using upper body motion in walking and trotting horses

Objectively assessing horse movement symmetry as an adjunctive to the routine lameness evaluation is on the rise with several commercially available systems on the market. Prerequisites for quantifying such symmetries include knowledge of the gait and gait events, such as hoof to ground contact patterns over consecutive strides. Extracting this information in a robust and reliable way is essential to accurately calculate many kinematic variables commonly used in the field. In this study, optical motion capture was used to measure 222 horses of various breeds, performing a total of 82 664 steps in walk and trot under different conditions, including soft, hard and treadmill surfaces as well as moving on a straight line and in circles. Features were extracted from the pelvis and withers vertical movement and from pelvic rotations. The features were then used in a quadratic discriminant analysis to classify gait and to detect if the left/right hind limb was in contact with the ground on a step by step basis. The predictive model achieved 99.98% accuracy on the test data of 120 horses and 21 845 steps, all measured under clinical conditions. One of the benefits of the proposed method is that it does not require the use of limb kinematics making it especially suited for clinical applications where ease of use and minimal error intervention are a priority. Future research could investigate the extension of this functionality to classify other gaits and validating the use of the algorithm for inertial measurement units