1,257 research outputs found
A Pluralistic Theory of Wordhood
What are words and how should we individuate them? There are two main answers on the philosophical market. For some, words are bundles of structural-functional features defining a unique performance profile. For others, words are non-eternal continuants individuated by their causal-historical ancestry. These conceptions offer competing views of the nature of words, and it seems natural to assume that at most one of them can capture the essence of wordhood. This paper makes a case for pluralism about wordhood: the view that there is a plurality of acceptable conceptions of the nature of words, none of which is uniquely entitled to inform us as to what wordhood consists in
Ca. Nitrososphaera and Bradyrhizobium are inversely correlated and related to agricultural practices in long-term field experiments
Agricultural land management, such as fertilization, liming, and tillage affects soil properties, including pH, organic matter content, nitrification rates, and the microbial community. Three different study sites were used to identify microorganisms that correlate with agricultural land use and to determine which factors regulate the relative abundance of the microbial signatures of the agricultural land-use. The three sites included in this study are the Broadbalk Experiment at Rothamsted Research, UK, the Everglades Agricultural Area, Florida, USA, and the Kellogg Biological Station, Michigan, USA. The effects of agricultural management on the abundance and diversity of bacteria and archaea were determined using high throughput, barcoded 16S rRNA sequencing. In addition, the relative abundance of these organisms was correlated with soil features. Two groups of microorganisms involved in nitrogen cycle were highly correlated with land use at all three sites. The ammonia oxidizing-archaea, dominated by Ca. Nitrososphaera, were positively correlated with agriculture while a ubiquitous group of soil bacteria closely related to the diazotrophic symbiont, Bradyrhizobium, was negatively correlated with agricultural management. Analysis of successional plots showed that the abundance of ammonia oxidizing-archaea declined and the abundance of bradyrhizobia increased with time away from agriculture. This observation suggests that the effect of agriculture on the relative abundance of these genera is reversible. Soil pH and NH(3) concentrations were positively correlated with archaeal abundance but negatively correlated with the abundance of Bradyrhizobium. The high correlations of Ca. Nitrososphaera and Bradyrhizobium abundances with agricultural management at three long-term experiments with different edaphoclimatic conditions allowed us to suggest these two genera as signature microorganisms for agricultural land use
Photographic Validation of Target Versus Nontarget Take of Brown Treesnake Baits
Use of toxic baits or other tools for managing nuisance species must ensure that the species of interest is adequately targeted while exposure to nontarget species is minimized. Nontarget takes of acetaminophen‐laced baits for control of invasive brown treesnakes (Boiga irregularis) on Guam may put those animals at risk of lethal intoxication and render the bait unavailable to the intended target species. We used wildlife cameras to identify species removing toxic and nontoxic baits from brown treesnake bait stations designed to exclude nontarget taxa in 2015 and 2016. Throughout various sites and habitat types, and balanced by season (wet vs. dry), we monitored 512 bait stations. From those, 140 of the baits were taken and the species taking the bait was successfully identified. Brown treesnakes took 124 (88.6%) of the baits, 13 (9.3%) were taken by small coconut crabs (Birgus latro), and 3 (2.1%) were taken by monitor lizards (Varanus indicus). The greatest incidence of nontarget bait takes was by small coconut crabs at 2 adjacent sites atop the same cliff line during a single season; 96.9% of bait takes at all other sites were by brown treesnakes. Bait takes by brown treesnakes were particularly infrequent (2.3%) at sites associated with endangered swiftlet (Aerodramus bartschi) caves where intensive snake control was employed. Although the majority of baits in bait stations are taken by brown treesnakes, local and temporal pulses in nontarget species activity, particularly by crabs, may bias results, which would not be accounted for without supplemental validation by cameras
Multi-center planning study of radiosurgery for intracranial metastases through Automation (MC-PRIMA) by crowdsourcing prior web-based plan challenge study
BACKGROUND: Planning radiosurgery to multiple intracranial metastases is complex and shows large variability in dosimetric quality among planners and treatment planning systems (TPS). This project aimed to determine whether autoplanning using the Muliple Brain Mets (AutoMBM) software can improve plan quality and reduce inter-planner variability by crowdsourcing results from prior international planning study. METHODS: Twenty-four institutions autoplanned with AutoMBM on a five metastases case from a prior international planning competition from which population statistics (means and variances) of 23 dosimetric metrics and resulting composite plan score (maximum score = 150) of other TPS (Eclipse, Monaco, RayStation, iPlan, GammaPlan, MultiPlan) were crowdsourced. Plan results of AutoMBM and each of the other TPS were compared using two sample t-tests for means and Levene's tests for variances. Plan quality of AutoMBM was correlated with the planner' experience and compared between academic and non-academic centers. RESULTS: AutoMBM produced plans with comparable composite plan score to GammaPlan, MultiPlan, Eclipse and iPlan (127.6 vs. 131.7 vs. 127.3 vs. 127.3 and 126.7; all p > 0.05) and superior to Monaco and RayStation (118.3 and 108.6; both p 0.05). CONCLUSIONS: By plan crowdsourcing prior international plan challenge, AutoMBM produces high and consistent plan quality independent of the planning experience and the institution that is crucial to addressing the technical bottleneck of SRS to intracranial metastases
Nonvolatile ferroelectric control of ferromagnetism in (Ga,Mn)As
There is currently much interest in materials and structures that provide
coupled ferroelectric and ferromagnetic responses, with a long-term goal of
developing new memories and spintronic logic elements. Within the field there
is a focus on composites coupled by magnetostrictive and piezoelectric strain
transmitted across ferromagnetic-ferroelectric interfaces, but substrate
clamping limits the response in the supported multilayer configuration favoured
for devices. This constraint is avoided in a ferroelectric-ferromagnetic
bilayer in which the magnetic response is modulated by the electric field of
the poled ferroelectric. Here, we report the realization of such a device using
a diluted magnetic semiconductor (DMS) channel and a polymer ferroelectric
gate. Polarization reversal of the gate by a single voltage pulse results in a
persistent modulation of the Curie temperature as large as 5%. The device
demonstrates direct and quantitatively understood electric-fieldmediated
coupling in a multiferroic bilayer and may provide new routes to nanostructured
DMS materials and devices via ferroelectric domain nanopatterning. The
successful implementation of a polymer-ferroelectric gate fieldeffect
transistor (FeFET) with a DMS channel adds a new functionality to semiconductor
spintronics and may be of importance for future low-voltage spintronics devices
and memory structures.Comment: 19 pages, 5 figure
Minimally Invasive Surgical Approaches and Traditional Total Hip Arthroplasty: A Meta-Analysis of Radiological and Complications Outcomes
BACKGROUND: Minimally invasive total hip arthroplasty (MITHA) remains considerably controversial. Limited visibility and prosthesis malposition increase the risk of post-surgical complications compared to those of the traditional method. METHODS: A meta-analysis was undertaken of all published databases up to May 2011. The studies were divided into four subgroups according to the surgical approach taken. The radiological outcomes and complications of minimally invasive surgery were compared to traditional total hip arthroplasty (TTHA) using risk ratio, mean difference, and standardized mean difference statistics. RESULTS: In five studies involving the posterolateral approach, no significant differences were found between the MITHA groups and the TTHA groups in the acetabular cup abduction angle (p = 0.41), acetabular anteversion (p = 0.96), and femoral prosthesis position (p = 0.83). However, the femoral offset was significantly increased (WMD = 3.00; 95% CI, 0.40-5.60; p = 0.02). Additionally, there were no significant differences among the complications in both the groups (dislocations, nerve injury, infection, deep vein thrombosis, proximal femoral fracture) and revision rate (p>0.05). In three studies involving the posterior approach, there were no significant differences in radiological outcomes or all other complications between MITHA or TTHA groups (p>0.05). Three studies involved anterolateral approach, while 2 studies used the lateral approach. However, the information from imaging and complications was not adequate for statistical analysis. CONCLUSIONS: Posterior MITHA seems to be a safe surgical procedure, without the increased risk of post-operative complication rates and component malposition rates. The posterolateral approach THA may lead to increased femoral offset. The current data are not enough to reach a positive conclusion that lateral and anterolateral approaches will result in increased risks of adverse effects and complications at the prosthesis site
Measurement of the Lifetime Difference Between B_s Mass Eigenstates
We present measurements of the lifetimes and polarization amplitudes for B_s
--> J/psi phi and B_d --> J/psi K*0 decays. Lifetimes of the heavy (H) and
light (L) mass eigenstates in the B_s system are separately measured for the
first time by determining the relative contributions of amplitudes with
definite CP as a function of the decay time. Using 203 +/- 15 B_s decays, we
obtain tau_L = (1.05 +{0.16}/-{0.13} +/- 0.02) ps and tau_H = (2.07
+{0.58}/-{0.46} +/- 0.03) ps. Expressed in terms of the difference DeltaGamma_s
and average Gamma_s, of the decay rates of the two eigenstates, the results are
DeltaGamma_s/Gamma_s = (65 +{25}/-{33} +/- 1)%, and DeltaGamma_s = (0.47
+{0.19}/-{0.24} +/- 0.01) inverse ps.Comment: 8 pages, 3 figures, 2 tables; as published in Physical Review Letters
on 16 March 2005; revisions are for length and typesetting only, no changes
in results or conclusion
Influence of surgical approach on component positioning in primary total hip arthroplasty
Background: Minimal invasive surgery (MIS) has gained growing popularity in total hip arthroplasty (THA) but concerns exist regarding component malpositioning. The aim of the present study was to evaluate femoral and acetabular component positioning in primary cementless THA comparing a lateral to a MIS anterolateral approach. Methods: We evaluated 6 week postoperative radiographs of 52 hips with a minimal invasive anterolateral approach compared to 54 hips with a standard lateral approach. All hips had received the same type of implant for primary cementless unilateral THA and had a healthy hip contralaterally. Results: Hip offset was equally restored comparing both approaches. No influence of the approach was observed with regard to reconstruction of acetabular offset, femoral offset, vertical placement of the center of rotation, stem alignment and leg length discrepancy. However, with the MIS approach, a significantly higher percentage of cups (38.5 %) was malpositioned compared to the standard approach (16.7 %) (p = 0.022). Conclusions: The MIS anterolateral approach allows for comparable reconstruction of stem position, offset and center of rotation compared to the lateral approach. However, surgeons must be aware of a higher risk of cup malpositioning for inclination and anteversion using the MIS anterolateral approach
Information Technology to Support Improved Care For Chronic Illness
BackgroundIn populations with chronic illness, outcomes improve with the use of care models that integrate clinical information, evidence-based treatments, and proactive management of care. Health information technology is believed to be critical for efficient implementation of these chronic care models. Health care organizations have implemented information technologies, such as electronic medical records, to varying degrees. However, considerable uncertainty remains regarding the relative impact of specific informatics technologies on chronic illness care.ObjectiveTo summarize knowledge and increase expert consensus regarding informatics components that support improvement in chronic illness care.DesignA systematic review of the literature was performed. "Use case" models were then developed, based on the literature review, and guidance from clinicians and national quality improvement projects. A national expert panel process was conducted to increase consensus regarding information system components that can be used to improve chronic illness care.ResultsThe expert panel agreed that informatics should be patient-centered, focused on improving outcomes, and provide support for illness self-management. They concurred that outcomes should be routinely assessed, provided to clinicians during the clinical encounter, and used for population-based care management. It was recommended that interactive, sequential, disorder-specific treatment pathways be implemented to quickly provide clinicians with patient clinical status, treatment history, and decision support.ConclusionsSpecific informatics strategies have the potential to improve care for chronic illness. Software to implement these strategies should be developed, and rigorously evaluated within the context of organizational efforts to improve care
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