Modified Dispersion Relations from Closed Strings in Toroidal Cosmology

A long-standing problem of theoretical physics is the exceptionally small value of the cosmological constant $\Lambda \sim 10^{-120}$ measured in natural Planckian units. Here we derive this tiny number from a toroidal string cosmology based on closed strings. In this picture the dark energy arises from the correlation between momentum and winding modes that for short distances has an exponential fall-off with increasing values of the momenta.The freeze-out by the expansion of the background universe for these transplanckian modes may be interpreted as a frozen condensate of the closed-string modes in the three non-compactified spatial dimensions.Comment: 21 pages LaTeX. Clarification at end of Section 3. Modified Discussion Section. Two notes added. Title change

Prospective Mediation Models of Sleep, Pain, and Daily Function in Children With Arthritis Using Ecological Momentary Assessment

Sleep is an emerging area of concern in children with juvenile idiopathic arthritis (JIA). Research shows the presence of poor sleep quality and related adverse outcomes in pediatric pain populations, including JIA, but few studies have examined the prospective patterns of association between sleep and associated outcomes. This prospective study evaluated the direction and magnitude of associations between subjective sleep characteristics (sleep quality, difficulty initiating sleep, and sleep duration), pain intensity, and functional limitations in children with JIA. We hypothesized that pain intensity would partially mediate the relationship between sleep and functional limitations

Daily sleep quality and mood as predictors of pain in children with juvenile polyarticular arthritis.

Children with arthritis experience frequent pain, but the predictors of daily pain variations are largely unidentified. The goal of this study was to examine sleep quality as a predictor of pain in children with arthritis and to determine whether mood moderates this relationship

Humanin: A Novel Central Regulator of Peripheral Insulin Action

Decline in insulin action is a metabolic feature of aging and is involved in the development of age-related diseases including Type 2 Diabetes Mellitus (T2DM) and Alzheimer's disease (AD). A novel mitochondria-associated peptide, Humanin (HN), has a neuroprotective role against AD-related neurotoxicity. Considering the association between insulin resistance and AD, we investigated if HN influences insulin sensitivity.Using state of the art clamp technology, we examined the role of central and peripheral HN on insulin action. Continuous infusion of HN intra-cerebro-ventricularly significantly improved overall insulin sensitivity. The central effects of HN on insulin action were associated with activation of hypothalamic STAT-3 signaling; effects that were negated by co-inhibition of hypothalamic STAT-3. Peripheral intravenous infusions of novel and potent HN derivatives reproduced the insulin-sensitizing effects of central HN. Inhibition of hypothalamic STAT-3 completely negated the effects of IV HN analog on liver, suggesting that the hepatic actions of HN are centrally mediated. This is consistent with the lack of a direct effect of HN on primary hepatocytes. Furthermore, single treatment with a highly-potent HN analog significantly lowered blood glucose in Zucker diabetic fatty rats. Based upon the link of HN with two age-related diseases, we examined if there were age associated changes in HN levels. Indeed, the amount of detectable HN in hypothalamus, skeletal muscle, and cortex was decreased with age in rodents, and circulating levels of HN were decreased with age in humans and mice.We conclude that the decline in HN with age could play a role in the pathogenesis of age-related diseases including AD and T2DM. HN represents a novel link between T2DM and neurodegeneration and along with its analogues offers a potential therapeutic tool to improve insulin action and treat T2DM

Self-Reported Pain and Disease Symptoms Persist in Juvenile Idiopathic Arthritis Despite Treatment Advances: An Electronic Diary Study: Persistent Pain in JIA

To use electronic diaries (e-diaries) to determine whether pain, stiffness, and fatigue continue to be common, disabling symptoms in children with juvenile idiopathic arthritis (JIA) despite the use of aggressive treatments in contemporary medical management

Seroprevalence of Hepatitis E virus (HEV) in domestic non-commercial pigs reared in small-scale farms and wild boar in South of Brazil

Hepatitis E is a zoonotic emerging disease distributed worldwide. The domestic swine and wild boars (Sus scrofa) are known as important reservoirs of HEV although HEV infections have been detected in other animal species. The southern region of Brazil has the largest swine productions in the country, ranging from highly-specialized commercial swine productions to small-scale non-commercial pig farms. The small-scale farms allow interactions between wild boars and domestic pigs, when occasionally pathogens transmission can occur between these populations. The aim of this study was to determine HEV seroprevalence in non-commercial domestic pigs and wild boars from two southern Brazilian states (RS: Rio Grande do Sul; SC: Santa Catarina), and discuss if the consumption of raw or undercooked meat from these animals is a potential risk to public health. Animals from RS and SC States were sampled. Serum was harvested from wild boar hunted between 2012 and 2016, and from non-commercial small-scale pig farms in 2014. Overall 249 wild boars (56 from RS and 193 from SC) and 382 pigs (261 from RS and 121 from SC) were tested to detect anti-HEV IgG antibodies using a commercial HEV antibody ELISA kit (Thermo fisher), specific for swine. Overall difference was observed (P\u3c0.0001) regarding HEV seroprevalence between wild boar 4.42% (n=249) and non-commercial domestic pigs 46.60% (n=382). In relation to wild boars samples, higher seroprevalence for Hepatitis E was observed in RS (14.29%; n=56) and lower in SC (1.55%; n=193; P\u3c0.0004). In relation to pigs, RS had also higher seroprevalence (53.26%; n=261) than SC (32.23%; n=121; P\u3c0.0002). Although interactions between wild boar and non-commercial domestic pigs are known to occur, the lowest antibody detection in wild boar suggest that these contact may not be sufficient to explain seroprevalence in studied populations. Our results indicate that non-commercial pigs are a more likely source of infection for the human population than wild boar

Emotion Regulation Predicts Pain and Functioning in Children With Juvenile Idiopathic Arthritis: An Electronic Diary Study

Objectives This study utilized e-diaries to evaluate whether components of emotion regulation predict daily pain and function in children with juvenile idiopathic arthritis (JIA). Methods 43 children ages 8–17 years and their caregivers provided baseline reports of child emotion regulation. Children then completed thrice daily e-diary assessments of emotion, pain, and activity involvement for 28 days. E-diary ratings of negative and positive emotions were used to calculate emotion variability and to infer adaptive emotion modulation following periods of high or low emotion intensity. Hierarchical linear models were used to evaluate how emotion regulation related to pain and function. Results The attenuation of negative emotion following a period of high negative emotion predicted reduced pain; greater variability of negative emotion predicted higher pain and increased activity limitation. Indices of positive emotion regulation also significantly predicted pain. Conclusions Components of emotion regulation as captured by e-diaries predict important health outcomes in children with JIA

Parent Pain Responses as Predictors of Daily Activities and Mood in Children with Juvenile Idiopathic Arthritis: The Utility of Electronic Diaries

The present study used electronic diaries to examine how parent responses to their child's pain predict daily adjustment of children with juvenile idiopathic arthritis (JIA). Nine school-aged children with JIA along with one of their parents completed thrice-daily assessments of pain-related variables, activity participation, and mood using handheld computers (Palm® pilots) for 14 days, yielding a potential of 42 child and parent assessments for each dyad. Children provided information on current pain level, mood, and participation in social, physical, and school activities. Parents independently rated their own mood as well as their behavioral responses to their child's pain at the same time points using a separate handheld computer. Results of multilevel modeling analyses demonstrated that use of “protective” pain responses by parents significantly predicted decreases in child activity and positive mood, with an even stronger inverse relationship between protective pain response and positive mood observed in children with higher than average disease severity. Protective pain responses were not found to be significantly predictive of daily negative mood in children. The use of “distracting” responses by parents significantly predicted less child activity restrictions but only in children having higher disease severity. There also was an unexpected trend in which parent use of more distracting pain responses tended to be associated with lower child positive mood. These preliminary findings suggest the importance of the parent in influencing adjustment in children with JIA and lend support to the incorporation of parents into comprehensive pain management approaches. The potential benefits of using electronic daily diaries as a strategy to examine pain and adjustment in children with JIA pain are discussed

What Can WMAP Tell Us About The Very Early Universe? New Physics as an Explanation of Suppressed Large Scale Power and Running Spectral Index

The Wilkinson Microwave Anisotropy Probe microwave background data may be giving us clues about new physics at the transition from a ``stringy'' epoch of the universe to the standard Friedmann Robertson Walker description. Deviations on large angular scales of the data, as compared to theoretical expectations, as well as running of the spectral index of density perturbations, can be explained by new physics whose scale is set by the height of an inflationary potential. As examples of possible signatures for this new physics, we study the cosmic microwave background spectrum for two string inspired models: 1) modifications to the Friedmann equations and 2) velocity dependent potentials. The suppression of low ``l'' modes in the microwave background data arises due to the new physics. In addition, the spectral index is red (n<1) on small scales and blue (n>1) on large scales, in agreement with data.Comment: 18 pages, 2 figures, submitted for publication in Physical Review D, references added in this versio