6,420 research outputs found
Spin-triplet paired phases inside ferromagnet induced by Hund's rule coupling and electronic correlations: Application to
We discuss a mechanism of real-space spin-triplet pairing, alternative to
that due to quantum paramagnon excitations, and demonstrate its applicability
to . Both the Hund's rule ferromagnetic exchange and
inter-electronic correlations contribute to the same extent to the equal-spin
pairing, particularly in the regime in which the weak-coupling solution does
not provide any. The theoretical results, obtained within the
orbitally-degenerate Anderson lattice model, match excellently the observed
phase diagram for with the coexistent ferromagnetic (FM1) and
superconducting (-type) phase. Additionally, weak - and -type
paired phases appear in very narrow regions near the metamaganetic (FM2
FM1) and FM1 paramagnetic first-order
phase-transition borders, respectively. The values of magnetic moments in the
FM2 and FM1 states are also reproduced correctly in a semiquantitative manner.
The Hund's metal regime is also singled out as appearing near FM1-FM2 boundary
Automatic identification of gait events using an instrumented sock
Background: textile-based transducers are an emerging technology in which piezo-resistive properties of materials
are used to measure an applied strain. By incorporating these sensors into a sock, this technology offers the
potential to detect critical events during the stance phase of the gait cycle. This could prove useful in several
applications, such as functional electrical stimulation (FES) systems to assist gait.
Methods: we investigated the output of a knitted resistive strain sensor during walking and sought to determine
the degree of similarity between the sensor output and the ankle angle in the sagittal plane. In addition, we
investigated whether it would be possible to predict three key gait events, heel strike, heel lift and toe off, with a
relatively straight-forward algorithm. This worked by predicting gait events to occur at fixed time offsets from
specific peaks in the sensor signal.
Results: our results showed that, for all subjects, the sensor output exhibited the same general characteristics as
the ankle joint angle. However, there were large between-subjects differences in the degree of similarity between
the two curves. Despite this variability, it was possible to accurately predict gait events using a simple algorithm.
This algorithm displayed high levels of trial-to-trial repeatability.
Conclusions: this study demonstrates the potential of using textile-based transducers in future devices that provide active gait assistance
Mechanical and Chemical Control of Smooth Cordgrass in Waillapa Bay, Washington
We evaluated four methods to control smooth cordgrass
(Spartina alterniflora Loisel), hereafter spartina, in Willapa
Bay, Washington: mowing, mowing plus herbicide combination,
herbicide only for clones, and aerial application of herbicide
for meadows. (PDF has 7 pages.
Non-target Impacts to Eelgrass from Treatments to Control Spartina in Willapa Bay, Washington
Four methods to control the smooth cordgrass Spartina
(Spartina alterniflora) and the footwear worn by treatment personnelat several sites in Willapa Bay, Washington were evaluatedto determine the non-target impacts to eelgrass (Zostera japonica). Clone-sized infestations of Spartina were treated bymowing or a single hand-spray application of Rodeo® formulatedat 480 g L-1acid equivalence (ae) of the isopropylaminesalt of glyphosate (Monsanto Agricultural Co., St. Louis, MO;currently Dow AgroSciences, Indianapolis, IN) with the nonionic surfactant LI 700® (2% v/v) or a combination of mowing and hand spraying. An aerial application of Rodeo® with X-77 Spreader® (0.13% v/v) to a 2-ha meadow was also investigated. Monitoring consisted of measuring eelgrass shoot densities and
percent cover pre-treatment and 1-yr post-treatment. Impacts
to eelgrass adjacent to treated clones were determined 1 m
from the clones and compared to a control 5-m away. Impacts
from footwear were assessed at 5 equidistant intervals along a 10-m transect on mudflat and an untreated control transect at each of the three clone treatment sites. Impacts from the aerial application were determined by comparing shoot densities and percent cover 1, 3 and 10 m from the edge of the treated Spartina meadow to that at comparable distances from an untreated meadow. Methods utilized to control Spartina clones did not impact surrounding eelgrass at two of three sites. Decreases in
shoot densities observed at the third site were consistent across treatments. Most impacts to eelgrass from the footwear worn by treatment personnel were negligible and those that were significant were limited to soft mud substrate. The aerial application of the herbicide was associated with reductions in eelgrass (shoot density and percent cover) at two of the three sampling distances, but reductions on the control plot were greater. We conclude that the unchecked spread of Spartina is a far greater
threat to the survival and health of eelgrass than that from any of the control measures we studied. The basis for evaluating control measures for Spartina should be efficacy and logistical constraints and not impacts to eelgrass.
PDF is 7 pages
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Taming the Beast: Adopting a Collaborative Email Inbox
This poster addresses the move to a Google Collaborative Inbox for departmental aliases; this use of a collaborative technology focused our workflows, increased our email productivity, and allowed for valuable data analysis
The use of cattle ear-tags as patagial markers for large birds-a field assessment on adult and nestling Australian White Ibis
To test the effectiveness of patagial marking with cattle ear-tags for Australian White Ibis (Threskiornis molucca), 105 adults and 58 nestlings were fitted with tags on each wing. Resighting frequency of adults, survival of nestlings, breeding behavior and foraging movements were monitored. The resighting frequency of wing-tagged adults was compared with resightings of 160 adults marked with colored leg-bands. Survival rates of wing-tagged nestlings were compared with an equal sample of 58 nestlings fitted with colored leg-bands. Over six months, 96% of tagged adults were resighted and there was no indication of impaired flight, with foraging movements ranging up to 30 km. Wing-tagged adults were more likely (40%) than color-banded adults (28%) to be detected in a one-off survey three months after marking and 65% of tagged birds were observed nesting. Higher mortality was observed among smaller nestlings (\u3c1100 g) compared with larger nestlings marked with wing tags, but not among those marked with leg bands. Inspection of the wings of two adult and two juvenile birds recaptured 6-8 months after marking indicated only minor feather abrasion, although further study is needed to assess long-term impacts. Because patagially-fitted cattle ear-tags are more visible than colored leg bands, can be fitted quickly with minimal trauma, and seem to have few adverse effects, they appear to be an effective technique for individually marking large adult birds
Oxidation Reduction Potential of Developing Plaque, Periodontal Pockets and Gingival Sulci
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141573/1/jper0630.pd
Neutralizing antibody response during acute and chronic hepatitis C virus infection
Little is known about the role of Abs in determining the outcome of hepatitis C virus (HCV) infection. By using infectious retroviral pseudotypes bearing HCV glycoproteins, we measured neutralizing Ab (nAb) responses during acute and chronic HCV infection. In seven acutely infected health care workers, only two developed a nAb response that failed to associate with viral clearance. In contrast, the majority of chronically infected patients had nAbs. To determine the kinetics of strain-specific and crossreactive nAb emergence, we studied patient H, the source of the prototype genotype 1a H77 HCV strain. An early weak nAb response, specific for the autologous virus, was detected at seroconversion. However, neutralization of heterologous viruses was detected only between 33 and 111 weeks of infection. We also examined the development of nAbs in 10 chimpanzees infected with H77 clonal virus. No nAb responses were detected in three animals that cleared virus, whereas strain-specific nAbs were detected in six of the seven chronically infected animals after approximately 50 weeks of infection. The delayed appearance of high titer crossreactive nAbs in chronically infected patients suggests that selective mechanism(s) may operate to prevent the appearance of these Abs during acute infection. The long-term persistence of these nAbs in chronically infected patients may regulate viral replication
Direct optical observation of walls and disclination effects in active photonic devices
Liquid crystal tunable Bragg Gratings defined in planar substrates via a laser patterning technique exhibit complex wavelength tuning. This tuning displays threshold points and hysteresis. These tuning features are shown to be a manifestation of physical processes occurring in the confined geometry of our tunable devices. Such physical processes include the formation and removal of line disclinations and an associated wall. We discuss the effect of walls in the liquid crystal with regards to voltage tuning characteristics and whether they may allow faster wavelength tuning
In situ studies of algal biomass in relation to physicochemical characteristics of the Salt Plains National Wildlife Refuge, Oklahoma, USA
This is the first in a series of experiments designed to characterize the Salt Plains National Wildlife Refuge (SPNWR) ecosystem in northwestern Oklahoma and to catalogue its microbial inhabitants. The SPNWR is the remnant of an ancient ocean, encompassing ~65 km(2 )of variably hypersaline flat land, fed by tributaries of the Arkansas River. Relative algal biomass (i.e., chlorophyll concentrations attributed to Chlorophyll-a-containing oxygenic phototrophs) and physical and chemical parameters were monitored at three permanent stations for a one-year period (July 2000 to July 2001) using a nested block design. Salient features of the flats include annual air temperatures that ranged from -10 to 40°C, and similar to other arid/semi-arid environments, 15–20-degree daily swings were common. Shade is absent from the flats system; intense irradiance and high temperatures (air and sediment surface) resulted in low water availability across the SPNWR, with levels of only ca. 15 % at the sediment surface. Moreover, moderate daily winds were constant (ca. 8–12 km h(-1)), sometimes achieving maximum speeds of up to 137 km h(-1). Typical of freshwater systems, orthophosphate (PO(4)(3-)) concentrations were low, ranging from 0.04 to <1 μM; dissolved inorganic nitrogen levels were high, but spatially variable, ranging from ca. 250–600 μM (NO(3)(- )+ NO(2)(-)) and 4–166 μM (NH(4)(+)). Phototroph abundance was likely tied to nutrient availability, with high-nutrient sites exhibiting high Chl-a levels (ca. 1.46 mg m(-2)). Despite these harsh conditions, the phototrophic microbial community was unexpectedly diverse. Preliminary attempts to isolate and identify oxygenic phototrophs from SPNWR water and soil samples yielded 47 species from 20 taxa and 3 divisions. Our data indicate that highly variable, extreme environments might support phototrophic microbial communities characterized by higher species diversity than previously assumed
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