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Despite considerable public and scholarly debate about the role of social media in self-injurious thoughts and behaviors (SITBs), no comprehensive, quantitative synthesis of this literature has previously been undertaken. The current systematic review and meta-analysis examines associations between social media use and SITBs, including suicidal ideation, suicide plans, suicide attempts, and nonsuicidal self-injury (NSSI). A range of social media behaviors and experiences were identified, including cybervictimization and perpetration, exposure to and generation of SITB-related content, problematic use, sexting, social media importance, and frequency of use. A systematic search of PsycINFO, Medline, CINAHL, and the references of prior reviews yielded 61 eligible studies. Results largely suggested medium effect sizes for associations between specific social media constructs (cybervictimization, SITB-related social media use, problematic social media use) and SITBs. There was no association between frequency of social media use and SITBs; however, studies on this topic were limited. The majority of studies identified focused on cybervictimization, and results suggested positive associations with all SITBs, with the association between cybervictimization and suicidal ideation stronger for adolescents than adults. Overall, findings highlight the utility of examining specific social media behaviors and experiences, and point to the need for more research in this area., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The heterologous or non-specific effects (NSEs) of vaccines, at times defined as "off-target effects" suggest that they can affect the immune response to organisms other than their pathogen-specific intended purpose. These NSEs have been the subject of clinical, immunological and epidemiological studies and are increasingly recognized as an important biological process by a growing group of immunologists and epidemiologists. Much remain to be learned about the extent and underlying mechanisms for these effects. The conference "Off-target effects of vaccination" held in Annecy-France (June 8-10 2015) intended to take a holistic approach drawing from the fields of immunology, systems biology, epidemiology, bioinformatics, public health and regulatory science to address fundamental questions of immunological mechanisms, as well as translational questions about vaccines NSEs. NSE observations were examined using case-studies on live attenuated vaccines and non-live vaccines followed by discussion of studies of possible biological mechanisms. Some possible pathways forward in the study of vaccines NSE were identified and discussed by the expert group., (Copyright © 2016.)

Uniaxial tensile tests are commonly used to characterize the structural and material properties of tendons and ligaments. During these tests, the stress and strain distributions applied to the specimen are assumed to be uniform. However, few studies have investigated the strain distributions throughout the tissue. The purpose of this study was to use imaging techniques to measure the strains around the circumference of 11 mm wide Achilles tendon grafts during a uniaxial tensile test. Pairs of radiopaque beads with a diameter of 2mm were affixed around the mid-substance of the tendon in four different locations. The motion of the beads was recorded using a cine fluoroscope. This system was shown to measure the displacement of the beads with an accuracy of 0.02 mm. During the uniaxial tensile test, large variations in local tissue strains were observed. At 10 MPa of applied stress, the local tissue strain varied from an average of 2.5-8.7%, an increase in strain of more than three times. As a result of these large variations, the modulus calculated from the stress-strain data varied from an average of 217 to 897 MPa, an increase of approximately 4 times. Furthermore, these data suggest that underestimates of the elastic modulus may result if a uniform strain distribution is assumed. These results indicate that during uniaxial tensile tests, the assumption of uniform stress and strain distributions should be carefully considered and small, uniform specimens should be used when measuring the material properties of soft tissues.

There is considerable evidence to suggest that adenosine is a modulator of behavioral state. Our previous reports showed that perfusion of adenosine into the basal forebrain decreased wakefulness. Furthermore, prolonged wakefulness resulted in increased levels of extracellular adenosine in the basal forebrain of cats and rats. However, the longer-term consequences of prolonged wakefulness and increased adenosine are largely unknown. We report here an increase in the DNA binding activity of the transcription factor, nuclear factor-kappa B (NF-kappaB) following 3 h of sustained wakefulness in the rat basal forebrain. Moreover, this treatment led to the appearance of the p65 subunit of NF-kappaB in the nucleus, as determined by western blot analysis of nuclear proteins. This contrasted with undetectable levels in the sleeping controls. A concomitant disappearance of I-kappaB in cytoplasm suggested the degradation of this inhibitor of NF-kappaB. In the acute in vitro basal forebrain slice preparation, perfusion of adenosine increased NF-kappaB DNA binding while pretreatment of the slices with the A1 adenosine receptor antagonist, cyclopentyl-1-3-dimethylxanthine, significantly reduced NF-kappaB DNA binding. These results are compatible with the hypothesis that increases in the levels of adenosine in the basal forebrain, that occur during prolonged wakefulness, act through an A1 adenosine receptor and a second messenger system to increase the activity of the transcription factor NF-kappaB. We further hypothesize that some of the long duration effects of prolonged wakefulness/sleep deprivation on performance and physiology, often termed 'sleep debt', might be mediated through adenosine and its activation of NF-kappaB, which is known to alter the expression of several behavioral state regulatory factors.