A Frictional Cooling Demonstration Experiment with Protons

Muon cooling is the main technological obstacle in the building of a muon collider. A muon cooling scheme based on Frictional Cooling holds promise in overcoming this obstacle. An experiment designed to demonstrate the Frictional Cooling concept using protons was undertaken. Although the results were inconclusive in the observation of cooling, the data allowed for the qualification of detailed simulations which are used to simulate the performance of a muon collider.Comment: 24 Pages 16 figures 2 table

Cannabidiol impairs neural tube closure in mouse whole embryo culture

BACKGROUND: Cannabidiol (CBD) is a nonpsychoactive constituent of cannabis widely available as a dietary supplement. Previous reports that it impairs the retinoid, sonic hedgehog, and folate metabolism pathways raise concern that it may impair closure of the embryonic neural tube (NT), producing NT defects including spina bifida and exencephaly. METHODS: We undertook teratogenicity testing of CBD in mouse whole embryo culture. RESULTS: At concentrations that do not diminish embryo viability, growth, or axial rotation, CBD dose-dependently impairs cranial NT closure, increasing the proportion of embryos that develop exencephaly. It concomitantly diminishes closure of the spinal NT, the posterior neuropore (PNP), producing longer neuropores at the end of culture which is a hallmark of spina bifida risk. Exposure to CBD does not disrupt the formation of long F-actin cables in surface ectoderm cells flanking the PNP or folding of the neuroepithelium at predictable hinge points. At the cellular level, CBD exposure does not alter proliferation or apoptosis of the spinal neuroepithelium. DISCUSSION: Thus, CBD acts selectively as a neuroteratogen predisposing to spina bifida and exencephaly in mouse whole embryo culture at exposure levels not associated with overt toxicity. Large-scale testing of CBD's effects on NT closure, particularly in at-risk groups, is warranted to inform its marketing to women of childbearing age

Associations between adjustment disorder and hospital-based infections in the Danish population.

OBJECTIVE:There is some evidence that posttraumatic stress disorder (PTSD) is associated with increased risk of infections, and it is unknown whether adjustment disorder is as well. We assessed the association between adjustment disorder and subsequent infections, and assessed additive interaction with sex. METHODS:The study population included a nationwide cohort of all Danish-born residents of Denmark diagnosed with adjustment disorder between 1995 and 2011, and an age- and sex-matched general population comparison cohort. We compared rates of infections requiring inpatient or outpatient hospitalization in the two cohorts. We fit Cox proportional hazards models to compute adjusted hazard ratios (aHR) for the associations between adjustment disorder and 32 types of infections, and calculated interaction contrasts to assess interaction between adjustment disorder and sex. RESULTS:Adjustment disorder was associated with increased rates of infections overall (n = 19,838 infections, aHR = 1.8, 95% confidence interval = 1.8. 1.9), and increased rates of each individual infection type (aHRs for 30 infections ranged from 1.5 to 2.3), adjusting for baseline psychiatric and somatic comorbidities and marital status. For many infection types (e.g., skin infections, pneumonia), interaction contrasts indicated rate differences were greater among men than women, while for two (urinary tract infections and sexually transmitted infections), rate differences were greater for women. CONCLUSIONS:These findings are consistent with studies examining the relationship between psychological stress and infections, and between PTSD and infections. They may be explained by a combination of the triggering of unhealthy behaviors as well as immune responses to stress

Active dynamic signage system: A full-scale evacuation trial

Efficient evacuation from transport terminals in an emergency can be constrained by the complex nature of the buildings. Although emergency signage systems are widely used as a well established means of facilitating evacuation, recent research demonstrates that only 38% of people 'see' conventional static emergency signage in simulated emergency situations. Besides, conventional signage only conveys single and passive information; therefore, they cannot be adapted to respond to developing evacuation situations. The EU FP7 GETWAY project addresses this problem for transport terminals through the development of an Intelligent Active Dynamic Signage System (IADSS), which routes terminal passengers to their optimal exit according to the distribution of occupants and the nature of the evolving incident. This paper presents the results of two full scale evacuation trials conducted in a rail station to establish the specific benefits of the Active Dynamic Signage System (i.e. ADSS, a subsystem of the IADSS without the intelligent component) over the current standard emergency signage system. These trials demonstrate that the flashing lights of the ADSS do have a greater effect on route choice compared to the standard signage system and therefore are more likely to promote the adoption of emergency evacuation procedures than would otherwise be the case, especially where evacuees are required to adopt routes not entirely based on proximity

Sclerostin's role in bone's adaptive response to mechanical loading

Mechanical loading is the primary functional determinant of bone mass and architecture, and osteocytes play a key role in translating mechanical signals into (re)modelling responses. Although the precise mechanisms remain unclear, Wnt signalling pathway components, and the anti-osteogenic canonical Wnt inhibitor Sost/sclerostin in particular, play an important role in regulating bone's adaptive response to loading. Increases in loading-engendered strains down-regulate osteocyte sclerostin expression, whereas reduced strains, as in disuse, are associated with increased sclerostin production and bone loss. However, while sclerostin up-regulation appears to be necessary for the loss of bone with disuse, the role of sclerostin in the osteogenic response to loading is more complex. While mice unable to down-regulate sclerostin do not gain bone with loading, Sost knockout mice have an enhanced osteogenic response to loading. The molecular mechanisms by which osteocytes sense and transduce loading-related stimuli into changes in sclerostin expression remain unclear but include several, potentially interlinked, signalling cascades involving periostin/integrin, prostaglandin, estrogen receptor, calcium/NO and Igf signalling. Deciphering the mechanisms by which changes in the mechanical environment regulate sclerostin production may lead to the development of therapeutic strategies that can reverse the skeletal structural deterioration characteristic of disuse and age-related osteoporosis and enhance bones' functional adaptation to loading. By enhancing the osteogenic potential of the context in which individual therapies such as sclerostin antibodies act it may become possible to both prevent and reverse the age-related skeletal structural deterioration characteristic of osteoporosis

Fatigue Crack Growth And Piezoelectric Property Decay Induced By Cyclic Electric Fields For An Actuation Piezoceramic

Degradation of piezoelectric properties of piezomaterials has long been a concern in the applications of actuators and sensors. In this work, alternating electric field induced fatigue crack growth and effect of cyclic electric field on piezoelectric property decay were characterized for a polarized PZT-PIC151. The results show that a relatively high alternating electric field drives the pre-existing microcracks to grow very fast initially due to the superposition of electrostriction induced stress and residual stress at the crack tip, then slow down gradually to becoming dormant. The butterfly loop evolution shows that cyclic electric field strongly degrades the piezoelectric properties due to the frequent domain switching. The output strain decays more than 50% after 106 electric cycles at 0.9 Ec for PIC 151 pellet bonded on an aluminum beam

Bone gain following loading is site-specifically enhanced by prior and concurrent disuse in aged male mice

The primary aim of osteoanabolic therapies is to strategically increase bone mass in skeletal regions likely to experience high strains. In the young healthy skeleton, this is primarily achieved by bone's adaptation to loading. This adaptation appears to fail with age, resulting in osteoporosis and fractures. We previously demonstrated that prior and concurrent disuse enhances bone gain following loading in old female mice. Here, we applied site specificity micro-computed tomography analysis to map regional differences in bone anabolic responses to axial loading of the tibia between young (19-week-old) and aged (19-month-old), male and female mice. Loading increased bone mass specifically in the proximal tibia in both sexes and ages. Young female mice gained more cortical bone than young males in specific regions of the tibia. However, these site-specific sex differences were lost with age such that bone gain following loading was not significantly different between old males and females. To test whether disuse enhances functional adaption in old male mice as it does in females, old males were subjected to sciatic neurectomy or sham surgery, and loading was initiated four days after surgery. Disuse augmented tibial cortical bone gain in response to loading in old males, but only in regions which were load-responsive in the young. Prior and concurrent disuse also increased loading-induced trabecular thickening in the proximal tibia of old males. Understanding how diminished background loading rejuvenates the osteogenic loading response in the old may improve osteogenic exercise regimes and lead to novel osteoanabolic therapies

Considerations for partnering with Ryan White Case Managers to create equitable opportunities for people with HIV to participate in research

Many research studies focus on recruitment from one or few HIV clinics or internet-engaged populations, but this may result in inequitable representation of people with HIV (PWH), across the rural/urban/suburban continuum. Ryan White Case Managers (RWCM) meet regularly with PWH, potentially positioning them as partners in gathering research-related data from diverse groups of low-income, marginalized, PWH. Yet, data collection in partnership with RWCM, particularly over large geographic areas, has been under-explored. We partnered with RWCM and their organizations throughout Florida to administer a 10-item technology use and willingness survey to clients living with HIV; RWCMs provided process-oriented feedback. Among 382 approached RWCM, 71% completed human subjects and survey administration training; 48% gathered data on 10 predetermined survey administration days; and 68% administered at least one survey during the entire period for survey administration. Altogether, 1,268 client surveys were completed, 2.7% by rural participants. Stigma, privacy concerns, and disinterest reportedly inhibited client participation; competing obligations, policies, and narrow recruitment windows prevented some RWCM from offering the survey to clients. Research should further explore strategies and best practices to ensure equitable access to participate in research among PWH

Gait stability at early stages of multiple sclerosis using different data sources

Background: People at early stages of multiple sclerosis have subtle balance problems that may affect gait stability. However, differences in methods of determining stability such as sensor type and placements, may lead to different results and affect their interpretation when comparing to controls and other studies. Questions: Do people with multiple sclerosis (PwMS) exhibit lower gait stability? Do location and type of data used to calculate stability metrics affect comparisons? Methods: 30 PwMS with no walking impairments as clinically measured and 15 healthy controls walked on a treadmill at 1.2 ms−1 while 3D acceleration data was obtained from sacrum, shoulder and cervical markers and from an accelerometer placed at the sacrum. The local divergence exponent was calculated for the four data sources. An ANOVA with group (multiple sclerosis and control) and data source as main factors was used to determine the effect of disease, data source and their interaction on stability metrics. Results: PwMS walked with significantly less stability according to all sensors (no interaction). A significant effect of data source on stability was also found, indicating that the local divergence exponent derived from sacrum accelerometer was lower than that derived from the other 3 sensor locations. Significance: PwMS with no evident gait impairments are less stable than healthy controls when walking on a treadmill. Although different data sources can be used to determine MS-related stability deterioration, a consensus about location and data source is needed. The local divergence exponent can be a useful measure of progression of gait instability at early stages of MS

Top Quark Physics at the Tevatron

We review the field of top-quark physics with an emphasis on experimental techniques. The role of the top quark in the Standard Model of particle physics is summarized and the basic phenomenology of top-quark production and decay is introduced. We discuss how contributions from physics beyond the Standard Model could affect top-quark properties or event samples. The many measurements made at the Fermilab Tevatron, which test the Standard Model predictions or probe for direct evidence of new physics using the top-quark event samples, are reviewed here.Comment: 50 pages, 17 figures, 2 tables; version accepted by Review of Modern Physic