Emergency department hyperoxia is associated with increased mortality in mechanically ventilated patients: A cohort study

Definitions of comorbid conditions. (DOCX 13 kb

Usual and Unusual Care: Existing Practice Control Groups in Randomized Controlled Trials of Behavioral Interventions

Objective: To evaluate the use of existing practice control groups in randomized controlled trials of behavioral interventions and the role of extrinsic health care services in the design and conduct of behavioral trials. Method: Selective qualitative review. Results: Extrinsic health care services, also known as nonstudy care, have important but under-recognized effects on the design and conduct of behavioral trials. Usual care, treatment-as-usual, standard of care, and other existing practice control groups pose a variety of methodological and ethical challenges, but they play a vital role in behavioral intervention research. Conclusions: This review highlights the need for a scientific consensus statement on control groups in behavioral trials

Water-Soluble Ruthenium Alkylidenes: Synthesis, Characterization, and Application to Olefin Metathesis in Protic Solvents

Ruthenium alkylidenes 6 and 7 bearing cationically functionalized phosphine ligands are soluble and stable in protic solvents and initiate olefin metathesis reactions in methanol, water, and aqueous emulsions. NMR spectroscopy data and X-ray diffraction analyses of alkylidene 6 suggested that these new alkylidenes were structurally similar to previously reported complexes of the type (PR_3)_2Cl_2Ru ═ CHR, in which the alkylidene substituents lie in the Cl−Ru−Cl plane. The anionic chloride ligands of complexes 6 and 7 were found to undergo facile ligand exchange reactions with other anions in protic solution. Both alkylidenes initiate the ring-opening metathesis polymerization (ROMP) of strained, cyclic olefins in water. However, the propagating species in these reactions decompose prior to complete consumption of monomer. These complexes initiate the quantitative, living polymerization of functionalized monomers in water in the presence of a Brønsted acid. Both chain termination and chain transfer reactions were experimentally demonstrated to be absent on the time scale of these acid-activated polymerizations. Alkylidenes 6 and 7 react readily with acyclic olefins:  alkylidene 6 reacted with trans-2-butene to yield a new ethylidene complex in either methanol or water, and the treatment of 6 with tri(ethylene glycol) methyl vinyl ether in water yielded water-soluble Fischer−carbene complex 16

Risk Profile and 3-Year Outcomes From the SYNTAX Percutaneous Coronary Intervention and Coronary Artery Bypass Grafting Nested Registries

ObjectivesThe aim of this study was to evaluate the use of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) in “real-world” patients unsuitable for the alternative treatment.BackgroundNo data are available on the risk profile and outcomes of patients that can only undergo PCI or CABG.MethodsIn the SYNTAX (Synergy between PCI with TAXUS and Cardiac Surgery) trial, a multidisciplinary Heart Team reached a consensus on whether PCI and CABG could result in clinical equipoise; if so, the patient was randomized. If not, the patient was enrolled in a CABG-ineligible PCI registry or PCI-ineligible CABG registry. A proportion (60%) of patients in the CABG registry was randomly assigned to be followed up for 5 years. No statistical comparisons were performed between randomized and registry patients. Major adverse cardiac or cerebrovascular event (MACCE) rates are presented as observational only.ResultsA total of 3,075 patients were treated in the SYNTAX trial; 198 (6.4%) and 1,077 (35.0%) patients were included in PCI and CABG registries, respectively. The main reason for inclusion in the CABG registry was too complex coronary anatomy (70.9%), and the main reason for inclusion in the PCI registry was too high-risk for surgery (70.7%). Three-year MACCE was 38.0% after PCI and 16.4% after CABG. Stratification by SYNTAX score terciles demonstrated a step-wise increase of MACCE rates in both PCI and CABG registries.ConclusionsThe SYNTAX Heart Team concluded that PCI and CABG remained the only treatment options for 6.4% and 35.0% of patients, respectively. Inoperable patients with major comorbidities that underwent PCI had high MACCE rates. In patients not suitable for PCI, surgical results were excellent. (SYNTAX Study: TAXUS Drug-Eluting Stent Versus Coronary Artery Bypass Surgery for the Treatment of Narrowed Arteries, NCT00114972

Entropy scaling in galaxy clusters: insights from an XMM-Newton observation of the poor cluster A1983

An XMM-Newton observation of the cool (kT=2.1 keV) cluster A1983, at z=0.044, is presented. Gas density and temperature profiles are calculated for the inner 500 h_{50}^{-1} kpc (~0.35 r_200). The outer regions of the surface brightness profile are well described with a beta model with beta=0.74, but the central regions require the introduction of a second component. The temperature profile is flat at the exterior with a slight dip towards the centre. The total mass profile, calculated assuming hydrostatic equilibrium, is consistent with an NFW profile, but with a low concentration parameter c=3.75 +/- 0.74. The M/L_B ratio profile shows that, at large scale, light traces mass to a reasonable extent, and the M/L_B ratio at 0.35 r_200 is consistent with the trends with mass observed in the optical. The M_Fe/L_B ratio is about two times less than that observed for a cluster at 5 keV. The gas mass fraction rises rapidly to level off at ~200 kpc; the value at 0.35 r_200 is ~8%. The scaling properties of the emission measure profile are consistent with the empirical relation \mgas \propto \Tx^{1.94}, and not with the self-similar relation \mgas \propto \Tx^{1.5}. Comparison of the entropy profile of A1983 with that of the hot cluster A1413 shows that the profiles are well scaled using the empirically determined relation S \propto \Tx^{0.65}, suggesting that the slope of the S-T relation is shallower than in the self-similar model. The form of the entropy profiles is remarkably similar, and there is no sign of a larger isentropic core in the cooler cluster. These data provide powerful agruments against preheating models. In turn, there is now increasing observational support for a trend of f_gas with system mass, which may go some way towards explaining the observed scaling behaviour. (Abridged.)Comment: Final refereed version to appear in A&A; Figs 2, 7, 11 and 12 are low re

Using intervention mapping and behavior change techniques to develop a digital intervention for self-management in stroke: Development study

BACKGROUND: Digital therapeutics, such as interventions provided via smartphones or the internet, have been proposed as promising solutions to support self-management in persons with chronic conditions. However, the evidence supporting self-management interventions through technology in stroke is scarce, and the intervention development processes are often not well described, creating challenges in explaining why and how the intervention would work. OBJECTIVE: This study describes a specific use case of using intervention mapping (IM) and the taxonomy of behavior change techniques (BCTs) in designing a digital intervention to manage chronic symptoms and support daily life participation in people after stroke. IM is an implementation science framework used to bridge the gap between theories and practice to ensure that the intervention can be implemented in real-world settings. The taxonomy of BCTs consists of a set of active ingredients designed to change self-management behaviors. METHODS: We used the first 4 steps of the IM process to develop a technology-supported self-management intervention, interactive Self-Management Augmented by Rehabilitation Technologies (iSMART), adapted from a face-to-face stroke-focused psychoeducation program. Planning group members were involved in adapting the intervention. They also completed 3 implementation measures to assess the acceptability, appropriateness, and feasibility of iSMART. RESULTS: In step 1, we completed a needs assessment consisting of assembling a planning group to codevelop the intervention, conducting telephone surveys of people after stroke (n=125) to identify service needs, and performing a systematic review of randomized controlled trials to examine evidence of the effectiveness of digital self-management interventions to improve patient outcomes. We identified activity scheduling, symptom management, stroke prevention, access to care resources, and cognitive enhancement training as key service needs after a stroke. The review suggested that digital self-management interventions, especially those using cognitive behavioral theory, effectively reduce depression, anxiety, and fatigue and enhance self-efficacy in neurological disorders. Step 2 identified key determinants, objectives, and strategies for self-management in iSMART, including knowledge, behavioral regulation, skills, self-efficacy, motivation, negative and positive affect, and social and environmental support. In step 3, we generated the intervention components underpinned by appropriate BCTs. In step 4, we developed iSMART with the planning group members. Especially, iSMART simplified the original psychoeducation program and added 2 new components: SMS text messaging and behavioral coaching, intending to increase the uptake by people after stroke. iSMART was found to be acceptable (mean score 4.63, SD 0.38 out of 5), appropriate (mean score 4.63, SD 0.38 out of 5), and feasible (mean score 4.58, SD 0.34 out of 5). CONCLUSIONS: We describe a detailed example of using IM and the taxonomy of BCTs for designing and developing a digital intervention to support people after stroke in managing chronic symptoms and maintaining active participation in daily life

Frequency and Clinical Determinants of Dementia after Ischemic Stroke

Objective: To investigate the frequency and clinical determinants of dementia after ischemic stroke. Methods: The authors administered neurologic, neuropsychological, and functional assessments to 453 patients (age 72.0 ± 8.3 years) 3 months after ischemic stroke. They diagnosed dementia using modified Diagnostic and Statistical Manual of Mental Disorders, 3rd ed., revised criteria requiring deficits in memory and two or more additional cognitive domains as well as functional impairment. Results: The authors diagnosed dementia in 119 of the 453 patients (26.3%). Regarding dementia subtypes, 68 of the 119 patients (57.1%) were diagnosed with vascular dementia, 46 patients (38.7%) were diagnosed with AD with concomitant stroke, and 5 patients (4.2%) had dementia for other reasons. Logistic regression suggested that dementia was associated with a major hemispheral stroke syndrome (OR 3.0), left hemisphere (OR 2.1) and right hemisphere (OR 1.8) infarct locations versus brainstem/cerebellar locations, infarcts in the pooled anterior and posterior cerebral artery territories versus infarcts in other vascular territories (OR 1.7), diabetes mellitus (OR 1.8), prior stroke (OR 1.7), age 80 years or older (OR 12.7) and 70 to 79 years (OR 3.9) versus 60 to 69 years, 8 or fewer years of education (OR 4.1) and 9 to 12 years of education (OR 3.0) versus 13 or more years of education, black race (OR 2.6) and Hispanic ethnicity (OR 3.1) versus white race, and northern Manhattan residence (OR 1.6). Conclusions: Dementia is frequent after ischemic stroke, occurring in one-fourth of the elderly patients in the authors’ cohort. The clinical determinants of dementia include the location and severity of the presenting stroke, vascular risk factors such as diabetes mellitus and prior stroke, and host characteristics such as older age, fewer years of education, and nonwhite race/ethnicity. The results also suggest that concomitant AD plays an etiologic role in approximately one-third of cases of dementia after stroke

The entropy and energy of intergalactic gas in galaxy clusters

Studies of the X-ray surface brightness profiles of clusters, coupled with theoretical considerations, suggest that the breaking of self-similarity in the hot gas results from an `entropy floor', established by some heating process, which affects the structure of the intracluster gas strongly in lower mass systems. Fitting analytical models for the radial variation in gas density and temperature to X-ray spectral images from the ROSAT PSPC and ASCA GIS, we derive gas entropy profiles for 20 galaxy clusters and groups. Scaling these profiles to coincide in the self-similar case, the lowest mass systems are found to have higher scaled entropy profiles than more massive systems. This appears to be due to a baseline entropy of 70-140 h50^-1/3 keV cm^2, depending on the extent to which shocks have been suppressed in low mass systems. The extra entropy may be present in all systems, but is detectable only in poor clusters, compared to the entropy generated by gravitational collapse. This excess entropy appears to be distributed uniformly with radius outside the central cooling regions. We determine the energy associated with this entropy floor, by studying the net reduction in binding energy of the gas in low mass systems, and find that it corresponds to a preheating temperature of ~0.3 keV. Since the relationship between entropy and energy injection depends upon gas density, we can combine the excesses of 70-140 keV cm^2 and 0.3 keV to derive the typical electron density of the gas into which the energy was injected. The resulting value of 1-3x10^-4 h50^1/2 cm-3, implies that the heating must have happened prior to cluster collapse but after a redshift z~7-10. The energy requirement is well matched to the energy from supernova explosions responsible for the metals which now pollute the intracluster gas.Comment: 15 pages, 10 figures, accepted for publication in MNRA

Metric Optimization for Surface Analysis in the Laplace-Beltrami Embedding Space

In this paper we present a novel approach for the intrinsic mapping of anatomical surfaces and its application in brain mapping research. Using the Laplace-Beltrami eigen-system, we represent each surface with an isometry invariant embedding in a high dimensional space. The key idea in our system is that we realize surface deformation in the embedding space via the iterative optimization of a conformal metric without explicitly perturbing the surface or its embedding. By minimizing a distance measure in the embedding space with metric optimization, our method generates a conformal map directly between surfaces with highly uniform metric distortion and the ability of aligning salient geometric features. Besides pairwise surface maps, we also extend the metric optimization approach for group-wise atlas construction and multi-atlas cortical label fusion. In experimental results, we demonstrate the robustness and generality of our method by applying it to map both cortical and hippocampal surfaces in population studies. For cortical labeling, our method achieves excellent performance in a cross-validation experiment with 40 manually labeled surfaces, and successfully models localized brain development in a pediatric study of 80 subjects. For hippocampal mapping, our method produces much more significant results than two popular tools on a multiple sclerosis study of 109 subjects