3,007 research outputs found
Allowing Cities to Raise the Minimum Wage Could Prevent Hundreds of Infant Deaths Annually
This research brief discusses findings that show each additional dollar of minimum wage reduces infant deaths by up to 1.8% annually in large U.S. cities. Over 1,400 infants could be saved annually if localities were allowed to raise the minimum wage to $15. State laws that prevent cities and counties from raising their minimum wage contribute to infant deaths
Gate Coupling to Nanoscale Electronics
The realization of single-molecule electronic devices, in which a
nanometer-scale molecule is connected to macroscopic leads, requires the
reproducible production of highly ordered nanoscale gaps in which a molecule of
interest is electrostatically coupled to nearby gate electrodes. Understanding
how the molecule-gate coupling depends on key parameters is crucial for the
development of high-performance devices. Here we directly address this,
presenting two- and three-dimensional finite-element electrostatic simulations
of the electrode geometries formed using emerging fabrication techniques. We
quantify the gate coupling intrinsic to these devices, exploring the roles of
parameters believed to be relevant to such devices. These include the thickness
and nature of the dielectric used, and the gate screening due to different
device geometries. On the single-molecule (~1nm) scale, we find that device
geometry plays a greater role in the gate coupling than the dielectric constant
or the thickness of the insulator. Compared to the typical uniform nanogap
electrode geometry envisioned, we find that non-uniform tapered electrodes
yield a significant three orders of magnitude improvement in gate coupling. We
also find that in the tapered geometry the polarizability of a molecular
channel works to enhance the gate coupling
Piloting Signs of Safety : A Deaf-Accessible Toolkit for Trauma and Addiction
The Deaf community - a minority group of 500,000 Americans who use American Sign Language (ASL) - experiences trauma and addiction at rates double to the general population. Yet, there are no evidence-based treatments that have been evaluated to treat trauma, addiction, or other behavioral health conditions among Deaf people.
Current evidence-based treatments fail to meet the needs of Deaf clients. One example is Seeking Safety, a well-validated therapy for people recovering from trauma and addiction. Seeking Safety includes a therapist guide and client handouts for 25 therapy sessions, each teaching clients a safe coping skill. When Seeking Safety was used with Deaf clients, unique barriers were revealed with regard to the client materials: they were presented in complex English instead of ASL, nor sensitive to Deaf people’s culture, social norms, and history of oppression.
To address these barriers, Dr. Anderson assembled a team of Deaf and hearing researchers, clinicians, filmmakers, actors, artists, and Deaf people in recovery to develop Signs of Safety, a Deaf-accessible toolkit to be used with Seeking Safety. Signs of Safety is comprised of a therapist companion guide and population-specific client materials, including visual handouts and ASL teaching stories on digital video, which present key learning points via an “educational soap opera.”
Dr. Anderson is currently leading a pilot study of Signs of Safety. Preliminary results show that participants are reporting symptom reduction from baseline to follow-up and high levels of satisfaction with the model, giving us the confidence to further pursue this line of research
Absence of singular superconducting fluctuation corrections to thermal conductivity
We evaluate the superconducting fluctuation corrections to thermal
conductivity in the normal state which diverge as T approaches T_c. We find
zero total contribution for one, two and three-dimensional superconductors for
arbitrary impurity concentration. The method used is diagrammatic many-body
theory, and all contributions -- Aslamazov-Larkin (AL), Maki-Thompson (MT), and
density-of-states (DOS) -- are considered. The AL contribution is convergent,
whilst the divergences of the DOS and MT diagrams exactly cancel.Comment: 4 pages text; 2 figure
Symptom Patterns of Posttraumatic Stress Disorder among Deaf Trauma Survivors
Details about Deaf people’s pattern of posttraumatic stress disorder (PTSD) symptoms remain relatively unknown due to inaccessible methods used in most epidemiological research. We conducted semi-structured American Sign Language interviews with 16 trauma-exposed Deaf individuals to explore their PTSD symptom patterns. Half met criteria for current PTSD, a rate higher than the general population. Underlying this disparity may be heightened rates of dissociation and psychogenic amnesia reported by many Deaf trauma survivors. Future research with large samples of Deaf survivors is needed to clarify this hypothesis, and to inform interventions that more accurately target Deaf people’s pattern of trauma symptoms
RAD54 family translocases counter genotoxic effects of RAD51 in human tumor cells.
The RAD54 family DNA translocases have several biochemical activities. One activity, demonstrated previously for the budding yeast translocases, is ATPase-dependent disruption of RAD51-dsDNA binding. This activity is thought to promote dissociation of RAD51 from heteroduplex DNA following strand exchange during homologous recombination. In addition, previous experiments in budding yeast have shown that the same activity of Rad54 removes Rad51 from undamaged sites on chromosomes; mutants lacking Rad54 accumulate nonrepair-associated complexes that can block growth and lead to chromosome loss. Here, we show that human RAD54 also promotes the dissociation of RAD51 from dsDNA and not ssDNA. We also show that translocase depletion in tumor cell lines leads to the accumulation of RAD51 on chromosomes, forming complexes that are not associated with markers of DNA damage. We further show that combined depletion of RAD54L and RAD54B and/or artificial induction of RAD51 overexpression blocks replication and promotes chromosome segregation defects. These results support a model in which RAD54L and RAD54B counteract genome-destabilizing effects of direct binding of RAD51 to dsDNA in human tumor cells. Thus, in addition to having genome-stabilizing DNA repair activity, human RAD51 has genome-destabilizing activity when expressed at high levels, as is the case in many human tumors
Non-BPS Solutions of the Noncommutative CP^1 Model in 2+1 Dimensions
We find non-BPS solutions of the noncommutative CP^1 model in 2+1 dimensions.
These solutions correspond to soliton anti-soliton configurations. We show that
the one-soliton one-anti-soliton solution is unstable when the distance between
the soliton and the anti-soliton is small. We also construct time-dependent
solutions and other types of solutions.Comment: 11 pages, minor correction
Fitting Event-History Models to Uneventful Data
Data with which to study disability dynamics usually take the form of successive current-status measures of disability rather than a record of events or spell durations. One recent paper presented a semi-Markov model of disability dynamics in which spell durations were inferred from sequences of current-status measures taken at 12-month intervals. In that analysis, it was assumed that no unobserved disablement transitions occurred between annual interviews. We use data from a longitudinal survey in which participants\u27 disability was measured at monthly intervals, and simulate the survival curves for remaining disabled that would be obtained with 1- and 12-month follow-up intervals. The median length of an episode of disability based on the 12-month interval data is over 22 months, while the true median, based on the 1-month interval data, is only one month
Modeling HER2 Effects on Cell Behavior from Mass Spectrometry Phosphotyrosine Data
Cellular behavior in response to stimulatory cues is governed by information encoded within a complex intracellular signaling network. An understanding of how phenotype is determined requires the distributed characterization of signaling processes (e.g., phosphorylation states and kinase activities) in parallel with measures of resulting cell function. We previously applied quantitative mass spectrometry methods to characterize the dynamics of tyrosine phosphorylation in human mammary epithelial cells with varying human epidermal growth factor receptor 2 (HER2) expression levels after treatment with epidermal growth factor (EGF) or heregulin (HRG). We sought to identify potential mechanisms by which changes in tyrosine phosphorylation govern changes in cell migration or proliferation, two behaviors that we measured in the same cell system. Here, we describe the use of a computational linear mapping technique, partial least squares regression (PLSR), to detail and characterize signaling mechanisms responsible for HER2-mediated effects on migration and proliferation. PLSR model analysis via principal component inner products identified phosphotyrosine signals most strongly associated with control of migration and proliferation, as HER2 expression or ligand treatment were individually varied. Inspection of these signals revealed both previously identified and novel pathways that correlate with cell behavior. Furthermore, we isolated elements of the signaling network that differentially give rise to migration and proliferation. Finally, model analysis identified nine especially informative phosphorylation sites on six proteins that recapitulated the predictive capability of the full model. A model based on these nine sites and trained solely on data from a low HER2-expressing cell line a priori predicted migration and proliferation in a HER2-overexpressing cell line. We identify the nine signals as a “network gauge,” meaning that when interrogated together and integrated according to the quantitative rules of the model, these signals capture information content in the network sufficiently to predict cell migration and proliferation under diverse ligand treatments and receptor expression levels. Examination of the network gauge in the context of previous literature indicates that endocytosis and activation of phosphoinositide 3-kinase (PI3K)-mediated pathways together represent particularly strong loci for the integration of the multiple pathways mediating HER2′s control of mammary epithelial cell proliferation and migration. Thus, a PLSR modeling approach reveals critical signaling processes regulating HER2-mediated cell behavior
Allowing Cities to Mandate Employer Paid Sick Leave Could Reduce Deaths among Working-Age Adults
Paid sick leave is good for health, yet there is no federal paid sick leave mandate, and U.S. states are increasingly preempting their city and county governments from mandating employer paid sick leave. This brief describes how working-age (ages 25-64) mortality rates from several external causes of premature death (suicide, homicide, drug overdose, alcohol poisoning, and transport accidents) from 1999 to 2019 may have been lower if states had not preempted cities and counties from mandating paid sick leave. The authors find that working-age mortality rates could have been over 7.5% lower in 2019 in cities and counties that were constrained by preemption laws if they had been able to mandate a 40-hour annual paid sick leave. The consequences of preemption laws are profound. They stymie local government innovation, constrain opportunities to take time off from work for medical care without financial repercussions, elevate risks of death among working-age adults, and contribute to geographic disparities in mortality
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