2,814 research outputs found
Program of Research on the Management of Research and Development Annual Report, 1965 - 1966 and Program Summary, 1960 - 1966
Research program on management of research and developmen
Program of research on the management of research and development Annual report, 1966-1967
Research program on methodologies of managing research and development project
Systematic review with meta‐analysis: race‐specific effects of alcohol and tobacco on the risk of oesophageal squamous cell carcinoma
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/100284/1/apt12514.pd
The mechanical response of semiflexible networks to localized perturbations
Previous research on semiflexible polymers including cytoskeletal networks in
cells has suggested the existence of distinct regimes of elastic response, in
which the strain field is either uniform (affine) or non-uniform (non-affine)
under external stress. Associated with these regimes, it has been further
suggested that a new fundamental length scale emerges, which characterizes the
scale for the crossover from non-affine to affine deformations. Here, we extend
these studies by probing the response to localized forces and force dipoles. We
show that the previously identified nonaffinity length [D.A. Head et al. PRE
68, 061907 (2003).] controls the mesoscopic response to point forces and the
crossover to continuum elastic behavior at large distances.Comment: 16 pages, 18 figures; substantial changes to text and figures to
clarify the crossover to continuum elasticity and the role of finite-size
effect
Bolus clearance in esophagogastric junction outflow obstruction is associated with strength of peristalsis
BackgroundA manometric diagnosis of esophagogastric junction outflow obstruction (EGJOO) without a mechanical cause creates a therapeutic conundrum. The aim of this study was to assess esophageal bolus clearance in EGJOO and assess manometric factors associated with clearance in EGJOO.MethodsBolus clearance was assessed using line‐tracing method and contour method to determine Complete Bolus Transit (CBT) and Functional Clearance (FC), respectively, on combined High‐Resolution Impedance Manometry (HRIM). HRIM studies of EGJOO patients, as well as a sample of achalasia types I‐III and asymptomatic controls, were retrospectively analyzed. In EGJOO, associations between Integrated Relaxation Pressure (IRP) or Distal Contractile Integral (DCI) and clearance were assessed using receiver‐operating‐characteristic (ROC) curves.Key ResultsSeventy‐five EGJOO, 28 achalasia, and 11 normal subjects were included. Agreement between CBT and FC was good (Kappa=0.75). CBT across swallows in each group was as follows: type I achalasia: 14%, type II achalasia: 8%, type III achalasia: 61%, EGJOO: 86%, and normal: 98% (p values .023, .006, and 610 mmHg‐s‐cm (accuracy 87.7%, P=.004). Complete Bolus Transit( CBT) across individual swallows was 97.8% when DCI>884 mmHg‐s‐cm (accuracy 81.9%, P900 mmHg‐s‐cm.Esophagogastric junction outflow obstruction (EGJOO) is a manometric diagnosis with unclear clinical significance. We studied bolus clearance in EGJOO, including in relationship to Distal Contractile Integral (DCI) and Integrated Relaxation Pressure (IRP). We found that intact peristalsis defined as a DCI of greater than 900 mmHg‐s‐cm is associated with complete bolus transit.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138211/1/nmo13093_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138211/2/nmo13093.pd
Word Embeddings for Entity-annotated Texts
Learned vector representations of words are useful tools for many information
retrieval and natural language processing tasks due to their ability to capture
lexical semantics. However, while many such tasks involve or even rely on named
entities as central components, popular word embedding models have so far
failed to include entities as first-class citizens. While it seems intuitive
that annotating named entities in the training corpus should result in more
intelligent word features for downstream tasks, performance issues arise when
popular embedding approaches are naively applied to entity annotated corpora.
Not only are the resulting entity embeddings less useful than expected, but one
also finds that the performance of the non-entity word embeddings degrades in
comparison to those trained on the raw, unannotated corpus. In this paper, we
investigate approaches to jointly train word and entity embeddings on a large
corpus with automatically annotated and linked entities. We discuss two
distinct approaches to the generation of such embeddings, namely the training
of state-of-the-art embeddings on raw-text and annotated versions of the
corpus, as well as node embeddings of a co-occurrence graph representation of
the annotated corpus. We compare the performance of annotated embeddings and
classical word embeddings on a variety of word similarity, analogy, and
clustering evaluation tasks, and investigate their performance in
entity-specific tasks. Our findings show that it takes more than training
popular word embedding models on an annotated corpus to create entity
embeddings with acceptable performance on common test cases. Based on these
results, we discuss how and when node embeddings of the co-occurrence graph
representation of the text can restore the performance.Comment: This paper is accepted in 41st European Conference on Information
Retrieva
Indeterminacy of Spatiotemporal Cardiac Alternans
Cardiac alternans, a beat-to-beat alternation in action potential duration
(at the cellular level) or in ECG morphology (at the whole heart level), is a
marker of ventricular fibrillation, a fatal heart rhythm that kills hundreds of
thousands of people in the US each year. Investigating cardiac alternans may
lead to a better understanding of the mechanisms of cardiac arrhythmias and
eventually better algorithms for the prediction and prevention of such dreadful
diseases. In paced cardiac tissue, alternans develops under increasingly
shorter pacing period. Existing experimental and theoretical studies adopt the
assumption that alternans in homogeneous cardiac tissue is exclusively
determined by the pacing period. In contrast, we find that, when calcium-driven
alternans develops in cardiac fibers, it may take different spatiotemporal
patterns depending on the pacing history. Because there coexist multiple
alternans solutions for a given pacing period, the alternans pattern on a fiber
becomes unpredictable. Using numerical simulation and theoretical analysis, we
show that the coexistence of multiple alternans patterns is induced by the
interaction between electrotonic coupling and an instability in calcium
cycling.Comment: 20 pages, 10 figures, to be published in Phys. Rev.
Coupled dynamics of voltage and calcium in paced cardiac cells
We investigate numerically and analytically the coupled dynamics of
transmembrane voltage and intracellular calcium cycling in paced cardiac cells
using a detailed physiological model and its reduction to a three-dimensional
discrete map. The results provide a theoretical framework to interpret various
experimentally observed modes of instability ranging from electromechanically
concordant and discordant alternans to quasiperiodic oscillations of voltage
and calcium
Evidence for Vertical Transmission of HPV from Mothers to Infants
Few large studies have evaluated concordance based on a broad spectrum of human papillomavirus (HPV) types in oral and genital specimens of mothers and their recently born infants. This information is important in determining whether HPV vaccines administered prior to pregnancy may be useful for preventing vertical transmission. HPV DNA was positive in 30% of mothers and 1.5% of newborns. Maternal/newborn concordance (HPV+/+ or HPV−/−) was 71%. Among HPV DNA+ mothers, only 3% of their infants were DNA+ and only 1 pair had the same HPV type. Among HPV− women, 0.8% of infants were HPV+. HPV DNA detected in hospitalized newborns reflects current infection transmitted to infants during pregnancy or delivery. None of the mother/baby HPV DNA+ concordance pairs detected viral types found in HPV vaccines suggesting that vaccination prior to pregnancy is unlikely to be efficacious in preventing vertical transmission
Images and nonlocal vortex pinning in thin superfluid films
For thin films of superfluid adsorbed on a disordered substrate, we derive
the equation of motion for a vortex in the presence of a random potential
within a mean field (Hartree) description of the condensate. The compressible
nature of the condensate leads to an effective pinning potential experienced by
the vortex which is nonlocal, with a long range tail that smoothes out the
random potential coupling the condensate to the substrate. We interpret this
nonlocality in terms of images, and relate the effective potential governing
the dynamics to the pinning energy arising from the expectation value of the
Hamiltonian with respect to the vortex wavefunction.Comment: 19 pages, revtex, to appear Phys. Rev.
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