32 research outputs found
Physiological Correlates of Volunteering
We review research on physiological correlates of volunteering, a neglected but promising research field. Some of these correlates seem to be causal factors influencing volunteering. Volunteers tend to have better physical health, both self-reported and expert-assessed, better mental health, and perform better on cognitive tasks. Research thus far has rarely examined neurological, neurochemical, hormonal, and genetic correlates of volunteering to any significant extent, especially controlling for other factors as potential confounds. Evolutionary theory and behavioral genetic research suggest the importance of such physiological factors in humans. Basically, many aspects of social relationships and social activities have effects on health (e.g., Newman and Roberts 2013; Uchino 2004), as the widely used biopsychosocial (BPS) model suggests (Institute of Medicine 2001). Studies of formal volunteering (FV), charitable giving, and altruistic behavior suggest that physiological characteristics are related to volunteering, including specific genes (such as oxytocin receptor [OXTR] genes, Arginine vasopressin receptor [AVPR] genes, dopamine D4 receptor [DRD4] genes, and 5-HTTLPR). We recommend that future research on physiological factors be extended to non-Western populations, focusing specifically on volunteering, and differentiating between different forms and types of volunteering and civic participation
Investigation of Genetic Variation Underlying Central Obesity amongst South Asians
The LOLIPOP study is supported by the National Institute for Health Research (NIHR) Comprehensive Biomedical Research Centre Imperial College Healthcare NHS Trust, the British Heart Foundation (SP/04/002), the Medical Research Council (G0601966,G0700931), the Wellcome Trust (084723/Z/08/Z), and the NIHR (RP-PG-0407-10371). The work was carried out in part at the NIHR/Wellcome Trust Imperial Clinical Research Facility. The Sikh Diabetes Study is supported by National Institute of Health grants KO1TW006087, funded by the Fogarty International Center, R01DK082766, funded by National Institute of Diabetes and Digestive and Kidney Diseases, and a seed grant from University of Oklahoma Health Sciences Center, Oklahoma City, USA. The Mauritius Family Study is supported by the Mauritius Ministry of Health and Quality of Life, Australian Government National Health and Medical Research Council NHMRC project grant numbers 1020285 and 1037916, the Victorian Government’s OIS Program, and partly funded by US National Institutes of Health Grant DK-25446. We thank the participants and research staff who made the study possible.South Asians are 1/4 of the world’s population and have increased susceptibility to central obesity and related cardiometabolic disease. Knowledge of genetic variants affecting risk of central obesity is largely based on genome-wide association studies of common SNPs in Europeans. To evaluate the contribution of DNA sequence variation to the higher levels of central obesity (defined as waist hip ratio adjusted for body mass index, WHR) among South Asians compared to Europeans we carried out: i) a genome-wide association analysis of >6M genetic variants in 10,318 South Asians with focused analysis of population-specific SNPs; ii) an exome-wide association analysis of ~250K SNPs in protein-coding regions in 2,637 South Asians; iii) a comparison of risk allele frequencies and effect sizes of 48 known WHR SNPs in 12,240 South Asians compared to Europeans. In genome-wide analyses, we found no novel associations between common genetic variants and WHR in South Asians at P<5x10-8; variants showing equivocal association with WHR (P<1x10-5) did not replicate at P<0.05 in an independent cohort of South Asians (N = 1,922) or in published, predominantly European meta-analysis data. In the targeted analyses of 122,391 population-specific SNPs we also found no associations with WHR in South Asians at P<0.05 after multiple testing correction. Exome-wide analyses showed no new associations between genetic variants and WHR in South Asians, either individually at P<1.5x10-6 or grouped by gene locus at P<2.5x10−6. At known WHR loci, risk allele frequencies were not higher in South Asians compared to Europeans (P = 0.77), while effect sizes were unexpectedly smaller in South Asians than Europeans (P<5.0x10-8). Our findings argue against an important contribution for population-specific or cosmopolitan genetic variants underlying the increased risk of central obesity in South Asians compared to Europeans.Yeshttp://www.plosone.org/static/editorial#pee
Deformation mechanism and process optimization of mechanical clinching joining technology used for steel and aluminum alloy sheets
Abstract. In this paper we construct several tools for manipulating pools of biases in the analysis of RC4. Then, we show that optimized strategies can break WEP based on 4000 packets by assuming that the first bytes of plaintext are known for each packet. We describe similar attacks for WPA. Firstly, we describe a distinguisher for WPA of complexity 2 43 and advantage 0.5 which uses 2 40 packets. Then, based on several partial temporary key recovery attacks, we recover the full 128-bit temporary key by using 2 38 packets. It works within a complexity of 2 96. So far, this is the best attack against WPA. We believe that our analysis brings further insights on the security of RC4.
Extreme violation of sleep hygiene: sleeping against the biological clock during a multiday relay event
Background: Sleep hygiene is important for sleep quality and optimal performance during the day. However, it is not always possible to follow sleep hygiene requirements. In multiday relay events, athletes have to sleep immediately after physical exertion and sometimes against their biological clock. Objectives: In this pilot study we investigated the effect of having to sleep at an abnormal circadian time on sleep duration. Patients and Methods: Eight runners and two cyclists performing a 500 km relay race were followed. They were divided into two groups that took turns in running and resting. Each group ran four times for approximately five hours while the other group slept. As a result, sleep times varied between normal and abnormal times. All athletes wore actigraphs to record the duration and onset of sleep. Results: Linear mixed model analyses showed that athletes slept on average 43 minutes longer when they slept during usual (night) times than during abnormal (day) times. In general, sleep duration decreased during the race with on average 18 minutes per period. Conclusions: This pilot study shows that, even under extreme violation of sleep hygiene rules, there still is an apparent effect of circadian rhythm on sleep duration in relay race athletes. Keywords: Athletes; Sleep; Circadian Rhyth
Discovery and Exploitation of New Biases in RC4
Abstract. In this paper, we present several weaknesses in the stream cipher RC4. First, we present a technique to automatically reveal linear correlations in the PRGA of RC4. With this method, 48 new exploitable correlations have been discovered. Then we bind these new biases in the PRGA with known KSA weaknesses to provide practical key recovery attacks. Henceforth, we apply a similar technique on RC4 as a black box, i.e. the secret key words as input and the keystream words as output. Our objective is to exhaustively find linear correlations between these elements. Thanks to this technique, 9 new exploitable correlations have been revealed. Finally, we exploit these weaknesses on RC4 to some practical examples, such as the WEP protocol. We show that these correlations lead to a key recovery attack on WEP with only 9800 encrypted packets (less than 20 seconds), instead of 24200 for the best previous attack.
Lightweight GPS-Tags, One Giant Leap for Wildlife Tracking? An Assessment Approach
Recent technological improvements have made possible the development of lightweight GPS-tagging devices suitable to track medium-to-small sized animals. However, current inferences concerning GPS performance are based on heavier designs, suitable only for large mammals. Lightweight GPS-units are deployed close to the ground, on species selecting micro-topographical features and with different behavioural patterns in comparison to larger mammal species. We assessed the effects of vegetation, topography, motion, and behaviour on the fix success rate for lightweight GPS-collar across a range of natural environments, and at the scale of perception of feral cats (Felis catus). Units deployed at 20 cm above the ground in sites of varied vegetation and topography showed that trees (native forest) and shrub cover had the largest influence on fix success rate (89% on average); whereas tree cover, sky availability, number of satellites and horizontal dilution of position (HDOP) were the main variables affecting location error (±39.5 m and ±27.6 m before and after filtering outlier fixes). Tests on HDOP or number of satellites-based screening methods to remove inaccurate locations achieved only a small reduction of error and discarded many accurate locations. Mobility tests were used to simulate cats' motion, revealing a slightly lower performance as compared to the fixed sites. GPS-collars deployed on 43 cats showed no difference in fix success rate by sex or season. Overall, fix success rate and location error values were within the range of previous tests carried out with collars designed for larger species. Lightweight GPS-tags are a suitable method to track medium to small size species, hence increasing the range of opportunities for spatial ecology research. However, the effects of vegetation, topography and behaviour on location error and fix success rate need to be evaluated prior to deployment, for the particular study species and their habitats