498 research outputs found
Recommended from our members
Envisioning the Caucus Community: Online Newspaper Editors Conceptualize Their Political Roles
This paper explores how local newspaper editors, as they move online and develop increasingly comprehensive and sophisticated Web sites, conceptualize the ways in which they might take advantage of the opportunities afforded by this new medium. To do so, it considers five caucus-specific sites in light of the notion of a potentially reinvigorated public sphere. The results suggest that despite the participatory nature of the medium, local newspapers' efforts to facilitate formation of an online democratic community remain tentative. Online editors recognize interactivity as a key attribute of the Web, but most are only just beginning to explore ways to move beyond their traditional role as information providers to create a space for meaningful political discourse
Vortex ratchet reversal at fractional matching fields in kagom\'e-like array with symmetric pinning centers
Arrays of Ni nanodots embedded in Nb superconducting films have been
fabricated by sputtering and electron beam lithography techniques. The arrays
are periodic triangular lattices of circular Ni dots arranged in a
kagom\'e-like pattern with broken reflection symmetry. Relevant behaviors are
found in the vortex lattice dynamics : i) At values lower than the first
integer matching field, several fractional matching fields are present when the
vortex lattice moves parallel or perpendicular to the reflection symmetry axis
of the array showing a clear anisotropic character in the magnetoresistance
curves, ii) injecting an ac current perpendicular to the reflection symmetry
axis of the array yields an unidirectional motion of the vortex lattice
(ratchet effect) as a result of the interaction between the whole vortex
lattice and the asymmetric lattice of dots, iii) increasing the input current
amplitudes the ratchet effect changes polarity independently of matching field
values. These experimental results can be explained taking into account the
vortex lattice density.Comment: 9 pages, 4 figures, 1 tabl
Directional vortex motion guided by artificially induced mesoscopic potentials
Rectangular pinning arrays of Ni dots define a potential landscape for vortex
motion in Nb films. Magnetotransport experiments in which two in-plane
orthogonal electrical currents are injected simultaneously allow selecting the
direction and magnitude of the Lorentz force on the vortex-lattice, thus
providing the angular dependence of the vortex motion. The background
dissipation depends on angle at low magnetic fields, which is progressively
smeared out with increasing field. The periodic potential locks in the vortex
motion along channeling directions. Because of this, vortex-lattice direction
of motion is up to 85o away from the applied Lorentz force direction.Comment: PDF file includes figure
Magnetic order and disorder in nanomagnets probed by superconducting vortices
We have studied two nanomagnet systems with strong (Co/Pd multilayers) and
weak (NdCo alloy films) stray magnetic fields by probing the out-of-plane
magnetic states with superconducting vortices. The hybrid samples are made of
array of nanomagnets embedded in superconducting Nb thin films. The vortex
motion detects relevant magnetic state features, since superconducting vortices
are able to discriminate between different magnetic stray field strengths and
directions. The usual matching effect between the superconducting vortex
lattice and the periodic pinning array can be quenched by means of disorder
magnetic potentials with strong stray fields at random. Ordered stray fields
retrieve the matching effect and yield asymmetry and shift in the vortex
dissipation signal. Furthermore vortices can discriminate the sizes of the
nanomagnet magnetic domains, detecting magnetic domain sizes as small as 70 nm.
In addition, we observe that the vortex cores play the crucial role instead of
the supercurrents around the vortex.Comment: 22 pages, 8 figure
Preferences, use of and satisfaction with mental health services among a sample of Puerto Rican cancer patients
OBJECTIVE: The purpose of this study was to describe the preferences, the use, satisfaction of mental health services (MHS) among a sample of Puerto Rican patients with cancer undergoing oncology treatment.
METHODS: A convenience sample of 120 patients diagnosed with cancer was recruited. Self-report questionnaires assessed socio-demographic and background questions, and the Mental Health Service Preference, Utilization and Satisfaction Questionnaire (MHSPUS). The Socio-demographic and Background Questionnaire inquired about participants\u27 demographic and socioeconomic characteristics, and included questions such as history of psychiatric diagnosis and spiritual practices. Univariate and Chi square analyses were used for descriptive purposes. Logistic regressions were used to explore associations between sociodemographic factors and MHS preferences and use.
RESULTS: The majority of the sample were females (53.8%), 61 and older (53.8%), and married or living with partner (57.1%), and reported an income equal to or less than $12,000 per year (44.4%), which places them under the US federal poverty line. Most of the participants (66.7%) reported being receptive to seeking services. Findings showed a significant association between living situation and past (p \u3c .05) and lifetime use (p \u3c .05) of MHS and past use of MHS. Participants living alone were more like to have used MHS in the past and during their lifetime. Adjusted logistic regression analyses revealed that living with someone was a protective factor for not using MHS in their lifetime (OR = 0.28; C1 = 0.08-0.95). Participants preferred to receive MHS at the oncology clinic, preferably on the date of their oncology appointments and during morning hours.
CONCLUSION: Findings support the integration of mental health services within the oncology practice setting
Long-term assessment of the translocation of an endangered primate into an agroforestry system
Translocation is increasingly being used as a conservation tool in wildlife management, but long-term assessments of the animals’ establishment in the new habitat are rarely done. In addition, finding protected areas for translocations can often be a limitation, but habitat patches managed for productive purposes could potentially be used for translocations. Here, we present a translocation case study of the Endangered Mexican howler monkey Alouatta palliata mexicana
into a forest fragment managed as an agroforest in the Los Tuxtlas Biosphere Reserve (Mexico). We compared the behavior of the translocated focal group 6 yr after translocation with that ob -
served 1 yr after translocation (Year 1 vs. Year 6), and with reference parameters for conserved forest. We also examined the 14 yr trajectory of the translocated population through published data. We found that in Year 6, monkeys spent less time on locomotion and more time consuming fruit than in Year 1. The focal group in Year 6 had doubled its activity area compared to Year 1. All behavioral parameters during Year 6 were similar to those reported for the species in conserved forest. During the first 14 yr, the translocated population increased at a rate of 1.29 ind. yr−1. We conclude that this translocation succeeded in establishing a thriving population and that certain agroforestry systems may be adequate habitat for primate translocations. We also discuss
how the translocation of howler monkeys into defaunated habitats might help restore ecological functions associated with these primates, such as the dispersal of large-seeded plants. Long-term information on successful primate translocations has high practical value for designing adequate conservation strategies in anthropogenic landscapes
- …