588 research outputs found
1-loop matching and NNLL resummation for all partonic 2 to 2 processes in QCD
The Wilson Coefficients for all 4-parton operators which arise in matching
QCD to Soft-Collinear Effective Theory (SCET) are computed at 1-loop. Any dijet
observable calculated in SCET beyond leading order will require these results.
The Wilson coefficients are separated by spin and color, although most
applications will involve only the spin-averaged hard functions. The anomalous
dimensions for the Wilson coefficients are given to 2-loop order, and the
renormalization group equations are solved explicitly. This will allow for
analytical resummation of dijet observables to next-to-next-to-leading
logarithmic accuracy. For each channel, there is a natural basis in which the
evolution is diagonal in color space. The same basis also diagonalizes the
color evolution for the soft function. Even though soft functions required for
SCET calculations are observable dependent, it is shown that their
renormalization group evolution is almost completely determined by a universal
structure. With these results, it will be possible to calculate hadronic event
shapes or other dijet observables to next-to-leading order with
next-to-next-to-leading log resummation.Comment: 28 pages, 5 tables; v2: typo corrected in Eq. (56
Peer Mentoring: Benefits to First-Time College Students and Their Peer Mentors
The experiences of first-year, first-time college students are impacted by a variety of challenges that pose a threat to student success and retention. One intervention universities are implementing to address these challenges are peer mentorship programs. While the benefits to first-time students of peer mentorship programs are well-researched, there is a lack of research on the benefits for mentors themselves. The purpose of this study was to examine the perceived and demonstrable benefits for peer mentors working within a first-year seminar. This mixed-methods study assessed both first-time student achievement outcomes (i.e., first-term GPA and one-year persistence; N = 7,154) as well as the professional and personal development benefits of peer mentors (n = 52). Results showed first-time students who participated in the peer mentor program had significantly higher student achievement and peer mentors themselves had increased academic self-efficacy, improved communication, leadership, and interpersonal presence, and strengthened social and professional networks
The Interactive Effect of Major Depression and Nonsuicidal Self-Injury On Current Suicide Risk and Lifetime Suicide Attempts
Objectives: This study examined the main and interactive effects of MDD and lifetime nonsuicidal self-injury (NSSI) on current suicide risk and past suicide attempts. We predicted that individuals with a history of NSSI and current MDD would be at greater suicide risk than those with either risk factor alone. An interaction between lifetime MDD and NSSI was hypothesized for past suicide attempts.
Methods: 204 substance dependent inpatients completed self-report measures and a diagnostic interview.
Results: Patients with both a history of NSSI and current MDD, relative to all other groups, had the greatest suicide risk. No support was found for the lifetime MDD by NSSI interaction.
Conclusion: Findings suggest the relevance of both NSSI and MDD in suicide risk
Functional neuroanatomy of meditation: A review and meta-analysis of 78 functional neuroimaging investigations
Meditation is a family of mental practices that encompasses a wide array of
techniques employing distinctive mental strategies. We systematically reviewed
78 functional neuroimaging (fMRI and PET) studies of meditation, and used
activation likelihood estimation to meta-analyze 257 peak foci from 31
experiments involving 527 participants. We found reliably dissociable patterns
of brain activation and deactivation for four common styles of meditation
(focused attention, mantra recitation, open monitoring, and
compassion/loving-kindness), and suggestive differences for three others
(visualization, sense-withdrawal, and non-dual awareness practices). Overall,
dissociable activation patterns are congruent with the psychological and
behavioral aims of each practice. Some brain areas are recruited consistently
across multiple techniques - including insula, pre/supplementary motor
cortices, dorsal anterior cingulate cortex, and frontopolar cortex - but
convergence is the exception rather than the rule. A preliminary effect-size
meta-analysis found medium effects for both activations (d = .59) and
deactivations (d = -.74), suggesting potential practical significance. Our
meta-analysis supports the neurophysiological dissociability of meditation
practices, but also raises many methodological concerns and suggests avenues
for future research
Influence of landscape attributes on Virginia opossum density
TheVirginia opossum (Didelphis virginiana), North America\u27s only marsupial, has a range extending from southern Ontario, Canada, to the Yucatan Peninsula, Mexico, and from the Atlantic seaboard to the Pacific. Despite the Virginia opossum\u27s taxonomic uniqueness in relation to other mammals in North America and rapidly expanding distribution, its ecology remains relatively understudied. Our poor understanding of the ecology of this important mesopredator is especially pronounced in the rural southeastern United States. Our goal was to estimate effects of habitat on opossum density within an extensive multiyear spatial capture‐recapture study. Additionally, we compared the results of this spatial capture‐recapture analysis with a simple relative abundance index. Opossum densities in the relatively underdeveloped regions of the southeastern United States were lower compared to the more human‐dominated landscapes of the Northeast and Midwest. In the southeastern United States, Virginia opossums occurred at a higher density in bottomland swamp and riparian hardwood forest compared to upland pine (Pinus spp.) plantations and isolated wetlands. These results reinforce the notion that the Virginia opossum is commonly associated with land cover types adjacent to permanent water (bottomland swamps, riparian hardwood). The relatively low density of opossums at isolated wetland sites suggests that the large spatial scale of selection demonstrated by opossums gives the species access to preferable cover types within the same landscape
A Plasmodium falciparum S33 proline aminopeptidase is associated with changes in erythrocyte deformability
Infection with the apicomplexan parasite Plasmodium falciparum is a major cause of morbidity and mortality worldwide. One of the Striking features of this parasite is its ability to remodel and decrease the deformability of host red blood cells, a process that contributes to disease. To further understand the virulence of Pf we investigated the biochemistry and function of a putative Pf S33 proline aminopeptidase (PJPAP). Unlike other P. falciparum aminopeptidases, PJPAP contains a predicted protein export element that is non-syntenic with other human infecting Plasmodium species. Characterization of PJPAP demonstrated that it is exported into the host red blood cell and that it is a prolyl aminopeptidase with a preference for N-terminal proline substrates. In addition genetic deletion of this exopeptidase was shown to lead to an increase in the deformability of parasite-infected red cells and in reduced adherence to the endothelial cell receptor CD36 under flow conditions. Our studies suggest that PJPAP plays a role in the rigidification and adhesion of infected red blood cells to endothelial surface receptors, a role that may make this protein a novel target for anti-disease interventions strategies. (C) 2016 Elsevier Inc. All rights reserved
Recommended from our members
Characterization of subsurface media from locations up- and down-gradient of a uranium-contaminated aquifer.
The processing of sediment to accurately characterize the spatially-resolved depth profiles of geophysical and geochemical properties along with signatures of microbial density and activity remains a challenge especially in complex contaminated areas. This study processed cores from two sediment boreholes from background and contaminated core sediments and surrounding groundwater. Fresh core sediments were compared by depth to capture the changes in sediment structure, sediment minerals, biomass, and pore water geochemistry in terms of major and trace elements including pollutants, cations, anions, and organic acids. Soil porewater samples were matched to groundwater level, flow rate, and preferential flows and compared to homogenized groundwater-only samples from neighboring monitoring wells. Groundwater analysis of nearby wells only revealed high sulfate and nitrate concentrations while the same analysis using sediment pore water samples with depth was able to suggest areas high in sulfate- and nitrate-reducing bacteria based on their decreased concentration and production of reduced by-products that could not be seen in the groundwater samples. Positive correlations among porewater content, total organic carbon, trace metals and clay minerals revealed a more complicated relationship among contaminant, sediment texture, groundwater table, and biomass. The fluctuating capillary interface had high concentrations of Fe and Mn-oxides combined with trace elements including U, Th, Sr, Ba, Cu, and Co. This suggests the mobility of potentially hazardous elements, sediment structure, and biogeochemical factors are all linked together to impact microbial communities, emphasizing that solid interfaces play an important role in determining the abundance of bacteria in the sediments
Collecting Symptoms and Sensor Data With Consumer Smartwatches (the Knee OsteoArthritis, Linking Activity and Pain Study):Protocol for a Longitudinal, Observational Feasibility Study
BACKGROUND: The Knee OsteoArthritis, Linking Activity and Pain (KOALAP) study is the first to test the feasibility of using consumer-grade cellular smartwatches for health care research. OBJECTIVE: The overall aim was to investigate the feasibility of using consumer-grade cellular smartwatches as a novel tool to capture data on pain (multiple times a day) and physical activity (continuously) in patients with knee osteoarthritis. Additionally, KOALAP aimed to investigate smartwatch sensor data quality and assess whether engagement, acceptability, and user experience are sufficient for future large-scale observational and interventional studies. METHODS: A total of 26 participants with self-diagnosed knee osteoarthritis were recruited in September 2017. All participants were aged 50 years or over and either lived in or were willing to travel to the Greater Manchester area. Participants received a smartwatch (Huawei Watch 2) with a bespoke app that collected patient-reported outcomes via questionnaires and continuous watch sensor data. All data were collected daily for 90 days. Additional data were collected through interviews (at baseline and follow-up) and baseline and end-of-study questionnaires. This study underwent full review by the University of Manchester Research Ethics Committee (#0165) and University Information Governance (#IGRR000060). For qualitative data analysis, a system-level security policy was developed in collaboration with the University Information Governance Office. Additionally, the project underwent an internal review process at Google, including separate reviews of accessibility, product engineering, privacy, security, legal, and protection regulation compliance. RESULTS: Participants were recruited in September 2017. Data collection via the watches was completed in January 2018. Collection of qualitative data through patient interviews is still ongoing. Data analysis will commence when all data are collected; results are expected in 2019. CONCLUSIONS: KOALAP is the first health study to use consumer cellular smartwatches to collect self-reported symptoms alongside sensor data for musculoskeletal disorders. The results of this study will be used to inform the design of future mobile health studies. Results for feasibility and participant motivations will inform future researchers whether or under which conditions cellular smartwatches are a useful tool to collect patient-reported outcomes alongside passively measured patient behavior. The exploration of associations between self-reported symptoms at different moments will contribute to our understanding of whether it may be valuable to collect symptom data more frequently. Sensor data-quality measurements will indicate whether cellular smartwatch usage is feasible for obtaining sensor data. Methods for data-quality assessment and data-processing methods may be reusable, although generalizability to other clinical areas should be further investigated. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/10238
Characterization of cleavage events in the multifunctional cilium adhesin Mhp684 (P146) reveals a mechanism by which mycoplasma hyopneumoniae regulates surface topography
Mycoplasma hyopneumoniae causes enormous economic losses to swine production worldwide by colonizing the ciliated epithelium in the porcine respiratory tract, resulting in widespread damage to the mucociliary escalator, prolonged inflammation, reduced weight gain, and secondary infections. Protein Mhp684 (P146) comprises 1,317 amino acids, and while the N-terminal 400 residues display significant sequence identity to the archetype cilium adhesin P97, the remainder of the molecule is novel and displays unusual motifs. Proteome analysis shows that P146 preprotein is endogenously cleaved into three major fragments identified here as P50P146, P40P146, and P85P146 that reside on the cell surface. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) identified a semitryptic peptide that delineated a major cleavage site in Mhp684. Cleavage occurred at the phenylalanine residue within sequence 672ATEF2QQ677, consistent with a cleavage motif resembling S/T-X-F2XD/E recently identified in Mhp683 and other P97/P102 family members. Biotinylated surface proteins recovered by avidin chromatography and separated by two-dimensional gel electrophoresis (2-D GE) showed that more-extensive endoproteolytic cleavage of P146 occurs. Recombinant fragments F1P146-F3P146 that mimic P50P146, P40P146, and P85P146 were constructed and shown to bind porcine epithelial cilia and biotinylated heparin with physiologically relevant affinity. Recombinant versions of F3P146 generated from M. hyopneumoniae strain J and 232 sequences strongly bind porcine plasminogen, and the removal of their respective C-terminal lysine and arginine residues significantly reduces this interaction. These data reveal that P146 is an extensively processed, multifunctional adhesin of M. hyopneumoniae. Extensive cleavage coupled with variable cleavage efficiency provides a mechanism by which M. hyopneumoniae regulates protein topography
- …