2,295 research outputs found
Worldsheet instantons and coupling selection rules in heterotic orbifolds
We review recent results on string coupling selection rules for heterotic
orbifolds, derived using conformal field theory. Such rules are the first step
towards understanding the viability of the recently obtained compactifications
with potentially realistic particle spectra. They arise from the properties of
the worldsheet instantons that mediate the couplings, and include stringy
effects that would seem 'miraculous' to an effective field theory observer.Comment: 4 pages, talk presented at SQS'13, JINR, Dubna, Russia, 29 July - 03
August, 201
Time Variable Faraday Rotation Measures of 3C-273 and 3C-279
Multifrequency polarimetry with the VLBA confirms the previously reported
time-varying Faraday rotation measure (RM) in the quasar 3C-279. Variability in
the RM and electric vector position angle (EVPA) of the jet component (C4) is
seen making it an unreliable absolute EVPA calibrator. 3C-273 is also shown to
vary its RM structure on 1.5 year time-scales. Variation in the RM properties
of quasars may result from a Faraday screen which changes on time-scales of a
few years, or from the motion of jet components which sample spatial variations
in the screen. A new component emerging from the core of 3C-279 appears to be
starting to sample such a spatial variation. Future monitoring of this
component and its RM properties is suggested as a diagnostic of the narrow line
region in 3C-279. We also present a new method of EVPA calibration using the
VLA Monitoring Program.Comment: Accepted to ApJ Letters. 12 pages, 5 figure
Dark matter cores in the Fornax and Sculptor dwarf galaxies: joining halo assembly and detailed star formation histories
We combine the detailed Star Formation Histories of the Fornax and Sculptor
dwarf Spheroidals with the Mass Assembly History of their dark matter (DM) halo
progenitors to estimate if the energy deposited by Supernova type II (SNeII) is
sufficient to create a substantial DM core. Assuming the efficiency of energy
injection of the SNeII into DM particles is , we find
that a single early episode, , that combines the
energy of all SNeII due to explode over 0.5 Gyr, is sufficient to create a core
of several hundred parsecs in both Sculptor and Fornax. Therefore, our results
suggest that it is energetically plausible to form cores in Cold Dark Matter
(CDM) halos via early episodic gas outflows triggered by SNeII. Furthermore,
based on CDM merger rates and phase-space density considerations, we argue that
the probability of a subsequent complete regeneration of the cusp is small for
a substantial fraction of dwarf-size haloes.Comment: ApJL accepted versio
Doing Gender: Cars and Culture in the United States
This qualitative research study aims to define and describe gender stereotypes and car culture. It will also explain how these stereotypes influence car culture and vice versa. This paper aims to explain how the mass media uses car culture in the United States and imposes gender stereotypes. The mass media I will be discussing includes but is not limited to commercials and magazine adverts. This paper asserts that by portraying what it means to be a man and what it means to be a woman, car companies build car culture and use pre-existing constructs of gender for marketing it. According to mainstream media and culture, the car people buy indicates how they perform gender. The commercials, culture, and even the dealerships are all designed to guide people to buy the right car for their gender
CHNA: The Role of the Hospital in Addressing Specific Community Health Needs
The Patient Protection and Affordable Care Act (ACA) added a requirement for nonprofit hospitals to keep their tax-exempt status under the Internal Revenue System Code 501(c) 3. This code requires all nonprofit hospitals to complete Community Health Needs Assessment (CHNA) reports every three years and must include input from community stakeholders and underserved individuals representing the low-income, minority and chronically ill population.
In addition to the CHNA, implementation strategies are required to be executed in the geographic areas served in order to meet the identified prioritized needs from the CHNA. Oftentimes, CHNAs are difficult to conceptualize and operationalize within the general acute care settings, especially in large health care systems. The current landscape calls on healthcare organizations to play an active role in total health for communities. It is important to integrate the necessary stakeholders within the organization and execute on an overarching strategy to provide services to the community.
Kaiser Permanente (KP) has been committed to community health through its mission, vision and values. Beyond that, there is a structure and dedicated public health resources in place for addressing the health needs of the communities served by KP. The national and regional community benefit departments within KP plays an active role in the organization and are often looked to for providing expertise on addressing community health needs.
In the recent past, KP launched a statewide effort to improve the behavioral health program. Senior leadership identified the need to strengthen processes in screening, treating and following up on behavioral health patients. It consisted of community outreach through television campaigns, improving clinic environments, screening in the emergency room, expanding behavioral health resources by way of hiring, etc. Nonetheless, a critical piece was missing - how the organization will serve the non-member population the same way it serves its members.
Although the treatment is intended to be equal for uninsured non-members, there is a difference in follow-up treatment and disposition of the patient due to benefits. In order to close this gap, community partnership and outreach is not only in the best interest of the individual, but also that of the organization. By investing resources and creating active partnerships in the community, KP can reduce costs, contribute significantly to the overall health of communities, and more effectively deliver on its mission.
To achieve this, the hospital must take on a collaborative and active role in screening, treating and catching patients who fall through the cracks and present in the emergency rooms. Patients who present in the emergency rooms have clear needs for follow-up and treatment, whether it is through KP or community health services. Nonetheless, KP should ensure patients have a follow up plan. This paper illustrates how hospitals can play a more active role in community health initiatives. The example presented is that of behavioral health needs in Richmond, California. Behavioral health encompasses mental health and substance use disorders
Faraday rotation and polarization gradients in the jet of 3C~120: Interaction with the external medium and a helical magnetic field?
We present a sequence of 12 monthly polarimetric 15, 22, and 43 GHz VLBA
observations of the radio galaxy 3C 120 revealing a systematic presence of
gradients in Faraday rotation and degree of polarization across and along the
jet. The degree of polarization increases with distance from the core and
toward the jet edges, and has an asymmetric profile in which the northern side
of the jet is more highly polarized. The Faraday rotation measure is also
stratified across the jet width, with larger values for the southern side. We
find a localized region of high Faraday rotation measure superposed on this
structure between approximately 3 and 4 mas from the core, with a peak of about
6000 rad/m^2. Interaction of the jet with the external medium or a cloud would
explain the confined region of enhanced Faraday rotation, as well as the
stratification in degree of polarization and the flaring of superluminal knots
when crossing this region. The data are also consistent with a helical field in
a two-fluid jet model, consisting of an inner, emitting jet and a sheath
containing nonrelativistic electrons. However, this helical magnetic field
model cannot by itself explain the localized region of enhanced Faraday
rotation. The polarization electric vectors, predominantly perpendicular to the
jet axis once corrected for Faraday rotation, require a dominant component
parallel to the jet axis (in the frame of the emitting plasma) for the magnetic
field in the emitting region.Comment: Accepted for publication in ApJ Letters. 4 pages (including 5
figures
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