3,089 research outputs found
Measurement of the underlying event in pp collisions using the ATLAS detector and development of a software suite for Bayesian unfolding
First measurements are made of the underlying event in calorimeter
jet events at the LHC, using 37 pb-1 of pp collisions at √s = 7TeV,
recorded during 2010 by the ATLAS detector. Results are compared
for an assumed di-jet topology based on a single identified jet, and an
exclusive di-jet requirement. The number of charged particles in the
azimuthal region transverse to the jet axis is recorded, as well as their
total and average transverse momentum. The total energy carried by
all particles - charged and neutral - is also calculated, using the full
calorimeter acceptance |η| < 4:8. Distributions are constructed to show
the variation of these quantities versus the transverse momentum of
the selected jet, over the range 20 - 800 GeV. Additional jets in the
transverse region are shown to dramatically influence the measured
activity.
Software is developed to perform Bayesian iterative unfolding, testing
closure of the process and stability with respect to the number of iterations
performed. Pseudo-experiments are used to propagate systematic
errors, and the intrinsic error due to unfolding is estimated. Although the
correction relies on a prior probablitity distribution, model-dependence
is reduced to an uncertainty comparable to or smaller than experimental
systematic errors.
The software is used to correct underlying event measurements
for effects introduced by the ATLAS detector. Unfolded results are
compared to predictions from different Monte Carlo event generators
used in LHC analyses, showing general agreement in the range |η| <
2:5, but discrepancies in the forward region. Comparison with other
ATLAS results shows compatible behaviour in events defined by any
high-momentum charged particle, or by leptonic Z-boson decays
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ARC OF RECREATION 2.0 Connecting the McKnight Rail Trail From Mason Square to Union Station, Springfield MA
ARC OF RECREATION 2.0
Connecting the McKnight Rail Trail From Mason Square to Union Station, Springfield MA
ARC OF RECREATION 2.0 is a Senior Urban Design Studio that created design concepts to envision the McKnight Rail Trail on an abandoned railroad corridor as a place to walk, bike, recreate, and congregate and to connect Mason Square to Union Station. Arc of Recreation was a name that was coined over 10 years ago through a different project at UMass. Finally realization is within reach. The City published a feasibility study in 2014 and has freed a construction budget of $430,000 for the first phases.The McKnight neighborhood hosts a diverse demographic that would benefit to an implemented rail trail in their community. With health complications including obesity and diabetes, the trail can provide a free means of transportation to the metro center that encourages an active lifestyle and increased employment in the neighborhood. Children will be able to utilize a safe passage to school, such as the nearby Rebecca M. Johnson Middle School, as well as young adults working part time jobs in the neighborhood and surrounding areas.
The trail will connect from Union Station in downtown to Mason Square in the east. Access along the trail route will enable more community members to enter the trail and use it. Therefore it creates a more equitable transportation network that can be shared by all residents.
The Studio created design concepts including first phase tactical interventions that make the street and public space experience enticing to visitors and engaging for the local residents, workers, and their families. The designs reflect the feedback of local community members through community meetings and a design charrette. In conclusion, the envisioned trail will foster community engagement and interaction to steer the future development of the neighborhood.
The following measures are crucial for a successful rail trail:
• Improvement of major street crossings to enable safe use of the trail during all day and nighttime hours.
• Integration of on street bike lanes and the trail to create a bicycle loop around the neighborhood. Expand the downtown bike-share stations for entry points to the trail.
• Create accessibility to public parks in the City through a network of safe streets with extensive tree plantings. Envision a trail that allows for access to the Connecticut River Walk and Bikeway.
• Embrace the industrial and underused architecture through public art.
• Protect existing wetlands on the trail through bypasses and boardwalks.
• Raise awareness for the rich ecology on the trail through signage and education.
• Create diverse opportunities to play for all ages and demographics.
• Create areas for urban gardening to connect trail and community.
• Creation of spaces on the trail where the community comes together and hold events and meetings.
• Design for activities throughout the year including the winter season.
• Rezone the trail to Open Space to guide its future development as a functioning rail trail
Dynamic Protein Interactions of the Polycomb Repressive Complex 2 during Differentiation of Pluripotent Cells
Polycomb proteins assemble to form complexes with important roles in epigenetic regulation. The Polycomb Repressive Complex 2 (PRC2) modulates the di- and tri-methylation of lysine 27 on histone H3, each of which are associated with gene repression. Although three subunits, EZH1/2, SUZ12, and EED, form the catalytic core of PRC2, a wider group of proteins associate with low stoichiometry. This raises the question of whether dynamic variation of the PRC2 interactome results in alternative forms of the complex during differentiation. Here we compared the physical interactions of PRC2 in undifferentiated and differentiated states of NTERA2 pluripotent embryonic carcinoma cells. Label-free quantitative proteomics was used to assess endogenous immunoprecipitation of the EZH2 and SUZ12 subunits of PRC2. A high stringency data set reflecting the endogenous state of PRC2 was produced that included all previously reported core and associated PRC2 components, and several novel interacting proteins. Comparison of the interactomes obtained in undifferentiated and differentiated cells revealed candidate proteins that were enriched in complexes isolated from one of the two states. For example, SALL4 and ZNF281 associate with PRC2 in pluripotent cells, whereas PCL1 and SMAD3 preferentially associate with PRC2 in differentiating cells. Analysis of the mRNA and protein levels of these factors revealed that their association with PRC2 correlated with their cell state-specific expression. Taken together, we propose that dynamic changes to the PRC2 interactome during differentiation may contribute to directing its activity during cell fate transitions
First Contact Practitioners' (FCPs) and General Practitioners' Perceptions Towards FCPs Delivering Vocational Advice to Patients with Musculoskeletal Conditions: A Qualitative Investigation of the Implementation Potential of the I-SWAP Initiative.
Purpose Musculoskeletal (MSK) pain is a common cause of work absence. The recent SWAP (Study of Work And Pain) randomised controlled trial (RCT) found that a brief vocational advice service for primary care patients with MSK pain led to fewer days' work absence and provided good return-on-investment. The I-SWAP (Implementation of the Study of Work And Pain) initiative aimed to deliver an implementation test-bed of the SWAP vocational advice intervention with First Contact Practitioners (FCP). This entailed adapting the SWAP vocational advice training to fit the FCP role. This qualitative investigation explored the implementation potential of FCPs delivering vocational advice for patients with MSK pain. Methods Semi-structured interviews and focus groups were conducted with 10 FCPs and 5 GPs. Data were analysed thematically and findings explored using Normalisation Process Theory (NPT). Results I-SWAP achieved a degree of 'coherence' (i.e. made sense), with both FCPs and GPs feeling FCPs were well-placed to discuss work issues with these patients. However, for many of the FCPs, addressing or modifying psychosocial and occupational barriers to return-to-work was not considered feasible within FCP consultations, and improving physical function was prioritised. Concerns were also raised that employers would not act on FCPs' recommendations regarding return-to-work. Conclusion FCPs appear well-placed to discuss work issues with MSK patients, and signpost/refer to other services; however, because they often only see patients once they are less suited to deliver other aspects of vocational advice. Future research is needed to explore how best to provide vocational advice in primary care settings
The Relative Merits of Posterior Surgical Treatments for Multi-Level Degenerative Cervical Myelopathy Remain Uncertain: Findings from a Systematic Review.
OBJECTIVES: To assess the reporting of study design and characteristics in multi-level degenerative cervical myelopathy (DCM) treated by posterior surgical approaches, and perform a comparison of clinical and radiographic outcomes between different approaches. METHODS: A literature search was performed in Embase and MEDLINE between 1995-2019 using a sensitive search string combination. Studies were selected by predefined selection criteria: Full text articles in English, with >10 patients (prospective) or >50 patients (retrospective), reporting outcomes of multi-level DCM treated by posterior surgical approach. RESULTS: A total of 75 studies involving 19,510 patients, conducted worldwide, were identified. Laminoplasty was described in 56 studies (75%), followed by laminectomy with (36%) and without fusion (16%). The majority of studies were conducted in Asia (84%), in the period of 2016-2019 (51%), of which laminoplasty was studied predominantly. Twelve (16%) prospective studies and 63 (84%) retrospective studies were identified. The vast majority of studies were conducted in a single centre (95%) with clear inclusion/exclusion criteria and explicit cause of DCM. Eleven studies (15%) included patients with ossification of the posterior longitudinal ligament exclusively with cohorts of 57 to 252. The clinical and radiographic outcomes were reported with heterogeneity when comparing laminoplasty, laminectomy with and without fusion. CONCLUSIONS: Heterogeneity in the reporting of study and sample characteristics exists, as well as in clinical and radiographic outcomes, with a paucity of studies with a higher level of evidence. Future studies are needed to elucidate the clinical effectiveness of posterior surgical treatments
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