2,345 research outputs found
A simple dependence between protein evolution rate and the number of protein-protein interactions
BACKGROUND: It has been shown for an evolutionarily distant genomic comparison that the number of protein-protein interactions a protein has correlates negatively with their rates of evolution. However, the generality of this observation has recently been challenged. Here we examine the problem using protein-protein interaction data from the yeast Saccharomyces cerevisiae and genome sequences from two other yeast species. RESULTS: In contrast to a previous study that used an incomplete set of protein-protein interactions, we observed a highly significant correlation between number of interactions and evolutionary distance to either Candida albicans or Schizosaccharomyces pombe. This study differs from the previous one in that it includes all known protein interactions from S. cerevisiae, and a larger set of protein evolutionary rates. In both evolutionary comparisons, a simple monotonic relationship was found across the entire range of the number of protein-protein interactions. In agreement with our earlier findings, this relationship cannot be explained by the fact that proteins with many interactions tend to be important to yeast. The generality of these correlations in other kingdoms of life unfortunately cannot be addressed at this time, due to the incompleteness of protein-protein interaction data from organisms other than S. cerevisiae. CONCLUSIONS: Protein-protein interactions tend to slow the rate at which proteins evolve. This may be due to structural constraints that must be met to maintain interactions, but more work is needed to definitively establish the mechanism(s) behind the correlations we have observed
C-axis Optical Sum Rule in Josephson Coupled Vortex State
Observed violations of the -axis optical sum rule can give important
information on deviations from in-plane Fermi liquid behavior and on the nature
of interlayer coupling between adjacent copper oxide planes. Application of a
magnetic field perpendicular to these planes is another way to probe in-plane
dynamics. We find that the optical sum rule is considerably modified in the
presence of the -axis magnetic field. Interlayer correlation of pancake
vortices is involved in the sum rule modification; however, details of the
vortex distribution in the plane are less important.Comment: one figure. To be published in PRB (Sep. 20001
The Smoking Gun: Can We Do for Gun Control What We Are Doing to Control the Vaping and E-Cigarettes Epidemic?
An editorial by UMass Medical School public health experts calls for legislators and policymakers to take bold action on gun control, similar to the recent ban in Massachusetts on vaping products in response to lung illnesses in vaping device and e-cigarette users
Magnon-Paramagnon Effective Theory of Itinerant Ferromagnets
The present work is devoted to the derivation of an effective
magnon-paramagnon theory starting from a microscopic lattice model of
ferromagnetic metals. For some values of the microscopic parameters it
reproduces the Heisenberg theory of localized spins. For small magnetization
the effective model describes the physics of weak ferromagnets in accordance
with the experimental results. It is written in a way which keeps O(3) symmetry
manifest,and describes both the order and disordered phases of the system.
Analytical expression for the Curie temperature,which takes the magnon
fluctuations into account exactly, is obtained. For weak ferromagnets is
well below the Stoner's critical temperature and the critical temperature
obtained within Moriya's theory.Comment: 14 pages, changed content,new result
A typology of longitudinal integrated clerkships
Context
Longitudinal integrated clerkships (LICs) represent a model of the structural redesign of clinical education that is growing in the USA, Canada, Australia and South Africa. By contrast with timeālimited traditional block rotations, medical students in LICs provide comprehensive care of patients and populations in continuing learning relationships over time and across disciplines and venues. The evidence base for LICs reveals transformational professional and workforce outcomes derived from a number of small institutionāspecific studies.
Objectives
This study is the first from an international collaborative formed to study the processes and outcomes of LICs across multiple institutions in different countries. It aims to establish a baseline reference typology to inform further research in this field.
Methods
Data on all LIC and LICālike programmes known to the members of the international Consortium of Longitudinal Integrated Clerkships were collected using a survey tool developed through a Delphi process and subsequently analysed. Data were collected from 54 programmes, 44 medical schools, seven countries and over 15 000 studentāyears of LICālike curricula.
Results
Wide variation in programme length, student numbers, health care settings and principal supervision was found. Three distinct typological programme clusters were identified and named according to programme length and discipline coverage: Comprehensive LICs; Blended LICs, and LICālike Amalgamative Clerkships. Two major approaches emerged in terms of the sizes of communities and types of clinical supervision. These referred to programmes based in smaller communities with mainly family physicians or general practitioners as clinical supervisors, and those in more urban settings in which subspecialists were more prevalent.
Conclusions
Three distinct LIC clusters are classified. These provide a foundational reference point for future studies on the processes and outcomes of LICs. The study also exemplifies a collaborative approach to medical education research that focuses on typology rather than on individual programme or context
Teen Distracted Reality an Interactive Virtual Education (D.R.I.V.E.): Experience and Impact on Teenage Drivers
Introduction: In 2013, 2,163 teens in the United States ages 16ā19 were killed and 243,243 were treated in emergency departments for injuries from motor vehicle crashes. distracted driving (i.e. texting, loud music, or phone conversations) and impaired driving (driving under the influence) play a role in these motor vehicle crashes. Prevention efforts aimed at high-risk teenager driving behavior may encourage safe driving habits.
Methods: The Teen D.R.I.V.E. program is a mobile driving simulator that provides teenagers with distracted and impaired driving scenarios. We administered anonymous surveys from April 2015-April 2016 to obtain demographic data and evaluate the programās impact on their driving behavior. We retrospectively analyzed survey responses using univariate and multivariate statistical analysis.
Results: A total of 1374 participants in the survey, however, 50 did not respond to the driving experience portion of the survey. Most participants (70%) were between 16-17 years of age years old and 51% were males. A majority (76%) of respondents had driving experience (26% permit, and 46% license) or had attended a driverās education course (67%). After experiencing the simulation respondents felt that the consequences of driving distracted (53%) and driving impaired (61%) were worse than previously expected. In addition, participants said that they would never drive distracted (70%) or drive impaired (90%). A majority of participants (72%) feel that simulation is the most effective way to teach driving related topics.
Conclusion: Teen D.R.I.V.E. offers a valuable experience to teenagers, teaching them about the dangers of driving distracted and impaired. Participants are likely to never drive impaired compared or distracted. Most teenagers feel simulation teaches these driving lessons most effectively
Conductivity sum rule, implication for in-plane dynamics and c-axis response
Recently observed -axis optical sum rule violations indicate non-Fermi
liquid in-plane behavior. For coherent -axis coupling, the observed flat,
nearly frequency independent -axis conductivity implies
a large in-plane scattering rate around and therefore any
pseudogap that might form at low frequency in the normal state will be smeared.
On the other hand incoherent -axis coupling places no restriction on the
value of and gives a more consistent picture of the observed sum rule
violation which, we find in some cases, can be less than half.Comment: 3 figures. To appear in PR
Spin-Wave Theory of the Spiral Phase of the t-J Model
A graded H.P,realization of the SU(2|1) algebra is proposed.A spin-wave
theory with a condition that the sublattice magnetization is zero is
discussed.The long-range spiral phase is investigated.The spin-spin correlator
is calculated.Comment: 17 page
Are Goods for Guns Good for the Community? An Update of a Community Gun Buyback Program
BACKGROUND: Gun violence remains a leading cause of death in the United States. Community gun buyback programs provide an opportunity to dispose of extraneous firearms. The purpose of this study was to understand the demographics, motivation, child access to firearms and household mental illness of buyback participants in hopes of improving the program\u27s effectiveness.
METHODS: A 2015 Injury Free Coalition for Kids gun buyback program which collaborated with local police departments was studied. We administered a 23-item questionnaire survey to gun buyback participants assessing demographic characteristics, motivation for relinquishing firearms, child firearm accessibility, and mental illness/domestic violence history.
RESULTS: A total of 186 individuals from Central/Western Massachusetts turned in 339 weapons. Participants received between 75 in gift cards dependent on what type of gun was turned in, with an average cost of $41/gun. A total of 109 participants (59%) completed the survey. Respondents were mostly white (99%), male (90%) and first-time participants in the program (85.2%). Among survey respondents, 54% turned in firearms for safety reasons . Respondents reported no longer needing/wanting their weapons (47%) and approximately one in eight participants were concerned the firearm(s) were accessible to children. Most respondents (87%) felt the program encouraged neighborhood awareness of firearm safety. Three out of every five participants reported that guns still remained in their homes, additionally; 21% where children could potentially access them and 14% with a history of mental illness/suicide/domestic violence in the home.
CONCLUSIONS: Gun buybacks can provide a low-cost means of removing unwanted firearms from the community. Most participants felt their homes were safer after turning in the firearm(s). In homes still possessing guns, emphasis on secure gun storage should continue increasing the safety of children and families. The results of this survey also provided new insights into the association between mental illness/suicide and gun ownership.
LEVEL OF EVIDENCE: Level III, Prognostic and Epidemiological
Non equilibrium effects in fragmentation
We study, using molecular dynamics techniques, how boundary conditions affect
the process of fragmentation of finite, highly excited, Lennard-Jones systems.
We analyze the behavior of the caloric curves (CC), the associated thermal
response functions (TRF) and cluster mass distributions for constrained and
unconstrained hot drops. It is shown that the resulting CC's for the
constrained case differ from the one in the unconstrained case, mainly in the
presence of a ``vapor branch''. This branch is absent in the free expanding
case even at high energies . This effect is traced to the role played by the
collective expansion motion. On the other hand, we found that the recently
proposed characteristic features of a first order phase transition taking place
in a finite isolated system, i.e. abnormally large kinetic energy fluctuations
and a negative branch in the TRF, are present for the constrained (dilute) as
well the unconstrained case. The microscopic origin of this behavior is also
analyzed.Comment: 21 pages, 11 figure
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