Showing papers by "Northwestern University published in 2005"
TL;DR: Nathaniel L. Rosi focuses on the rational assembly of DNA-modified nanostructures into larger-scale materials and their roles in biodiagnostic screening for nucleic acids.
Abstract: In the last 10 years the field of molecular diagnostics has witnessed an explosion of interest in the use of nanomaterials in assays for gases, metal ions, and DNA and protein markers for many diseases. Intense research has been fueled by the need for practical, robust, and highly sensitive and selective detection agents that can address the deficiencies of conventional technologies. Chemists are playing an important role in designing and fabricating new materials for application in diagnostic assays. In certain cases assays based upon nanomaterials have offered significant advantages over conventional diagnostic systems with regard to assay sensitivity, selectivity, and practicality. Some of these new methods have recently been reviewed elsewhere with a focus on the materials themselves or as subclassifications in more generalized overviews of biological applications of nanomaterials.1-7 We intend to review some of the major advances and milestones in the field of detection systems based upon nanomaterials and their roles in biodiagnostic screening for nucleic acids, * To whom correspondence should be addressed. Phone: 847-4913907. Fax: 847-467-5123. E-mail: chadnano@northwestern.edu. Nathaniel L. Rosi earned his B.A. degree at Grinnell College (1999) and his Ph.D. degree from the University of Michigan (2003), where he studied the design, synthesis, and gas storage applications of metal−organic frameworks under the guidance of Professor Omar M. Yaghi. In 2003 he began postdoctoral studies as a member of Professor Mirkin’s group at Northwestern University. His current research focuses on the rational assembly of DNA-modified nanostructures into larger-scale materials.
4,308 citations
University of Vermont1, Delft University of Technology2, Northwestern University3, Vrije Universiteit Brussel4, University of British Columbia5, Leiden University Medical Center6, University of Oregon7, University of Maryland, Baltimore8, State University of New York Upstate Medical University9, University of Massachusetts Lowell10
TL;DR: A definition of a joint coordinate system (JCS) for the shoulder, elbow, wrist, and hand is proposed and a standard for the local axis system in each articulating segment or bone is generated.
3,866 citations
TL;DR: A methodology is proposed that can find functional modules in complex networks, and classify nodes into universal roles according to their pattern of intra- and inter-module connections, which yields a ‘cartographic representation’ of complex networks.
Abstract: High-throughput techniques are leading to an explosive growth in the size of biological databases and creating the opportunity to revolutionize our understanding of life and disease Interpretation of these data remains, however, a major scientific challenge Here, we propose a methodology that enables us to extract and display information contained in complex networks1,2,3 Specifically, we demonstrate that we can find functional modules4,5 in complex networks, and classify nodes into universal roles according to their pattern of intra- and inter-module connections The method thus yields a ‘cartographic representation’ of complex networks Metabolic networks6,7,8 are among the most challenging biological networks and, arguably, the ones with most potential for immediate applicability9 We use our method to analyse the metabolic networks of twelve organisms from three different superkingdoms We find that, typically, 80% of the nodes are only connected to other nodes within their respective modules, and that nodes with different roles are affected by different evolutionary constraints and pressures Remarkably, we find that metabolites that participate in only a few reactions but that connect different modules are more conserved than hubs whose links are mostly within a single module
3,298 citations
TL;DR: Extracellular ATP regulates microglial branch dynamics in the intact brain, and its release from the damaged tissue and surrounding astrocytes mediates a rapid microglia response towards injury.
Abstract: Parenchymal microglia are the principal immune cells of the brain. Time-lapse two-photon imaging of GFP-labeled microglia demonstrates that the fine termini of microglial processes are highly dynamic in the intact mouse cortex. Upon traumatic brain injury, microglial processes rapidly and autonomously converge on the site of injury without cell body movement, establishing a potential barrier between the healthy and injured tissue. This rapid chemotactic response can be mimicked by local injection of ATP and can be inhibited by the ATP-hydrolyzing enzyme apyrase or by blockers of G protein-coupled purinergic receptors and connexin channels, which are highly expressed in astrocytes. The baseline motility of microglial processes is also reduced significantly in the presence of apyrase and connexin channel inhibitors. Thus, extracellular ATP regulates microglial branch dynamics in the intact brain, and its release from the damaged tissue and surrounding astrocytes mediates a rapid microglial response towards injury.
3,251 citations
TL;DR: While research in this field needs improvement in terms of rigor and quality, high-fidelity medical simulations are educationally effective and simulation-based education complements medical education in patient care settings.
Abstract: SUMMARY Review date: 1969 to 2003, 34 years. Background and context: Simulations are now in widespread use in medical education and medical personnel evaluation. Outcomes research on the use and effectiveness of simulation technology in medical education is scattered, inconsistent and varies widely in methodological rigor and substantive focus. Objectives: Review and synthesize existing evidence in educational science that addresses the question, ‘What are the features and uses of high-fidelity medical simulations that lead to most effective learning?’. Search strategy: The search covered five literature databases (ERIC, MEDLINE, PsycINFO, Web of Science and Timelit) and employed 91 single search terms and concepts and their Boolean combinations. Hand searching, Internet searches and attention to the ‘grey literature’ were also used. The aim was to perform the most thorough literature search possible of peer-reviewed publications and reports in the unpublished literature that have been judged for academic quality. Inclusion and exclusion criteria: Four screening criteria were used to reduce the initial pool of 670 journal articles to a focused set of 109 studies: (a) elimination of review articles in favor of empirical studies; (b) use of a simulator as an educational assessment or intervention with learner outcomes measured quantitatively; (c) comparative research, either experimental or quasi-experimental; and (d) research that involves simulation as an educational intervention. Data extraction: Data were extracted systematically from the 109 eligible journal articles by independent coders. Each coder used a standardized data extraction protocol. Data synthesis: Qualitative data synthesis and tabular presentation of research methods and outcomes were used. Heterogeneity of research designs, educational interventions, outcome measures and timeframe precluded data synthesis using meta-analysis. Headline results: Coding accuracy for features of the journal articles is high. The extant quality of the published research is generally weak. The weight of the best available evidence suggests that high-fidelity medical simulations facilitate learning under the right conditions. These include the following:
3,176 citations
TL;DR: The use of nanosphere lithography for the fabrication of highly reproducible and robust SERS substrates is described and progress in applying SERS to the detection of chemical warfare agents and several biological molecules is described.
Abstract: The ability to control the size, shape, and material of a surface has reinvigorated the field of surface-enhanced Raman spectroscopy (SERS). Because excitation of the localized surface plasmon resonance of a nanostructured surface or nanoparticle lies at the heart of SERS, the ability to reliably control the surface characteristics has taken SERS from an interesting surface phenomenon to a rapidly developing analytical tool. This article first explains many fundamental features of SERS and then describes the use of nanosphere lithography for the fabrication of highly reproducible and robust SERS substrates. In particular, we review metal film over nanosphere surfaces as excellent candidates for several experiments that were once impossible with more primitive SERS substrates (e.g., metal island films). The article also describes progress in applying SERS to the detection of chemical warfare agents and several biological molecules.
2,986 citations
TL;DR: It is anticipated that an increased understanding of the contributions of these recently identified pathways will advance current thinking about how interferons work.
Abstract: Interferons are cytokines that have antiviral, antiproliferative and immunomodulatory effects. Because of these important properties, in the past two decades, major research efforts have been undertaken to understand the signalling mechanisms through which these cytokines induce their effects. Since the original discovery of the classical JAK (Janus activated kinase)-STAT (signal transducer and activator of transcription) pathway of signalling, it has become clear that the coordination and cooperation of multiple distinct signalling cascades - including the mitogen-activated protein kinase p38 cascade and the phosphatidylinositol 3-kinase cascade - are required for the generation of responses to interferons. It is anticipated that an increased understanding of the contributions of these recently identified pathways will advance our current thinking about how interferons work.
2,912 citations
TL;DR: A systematic review of the literature regarding how activity in diverse brain regions creates and modulates the experience of acute and chronic pain states, emphasizing the contribution of various imaging techniques to emerging concepts is presented in this paper.
2,686 citations
TL;DR: In this article, the authors measure the effect of Catholic high school attendance on educational attainment and test scores, and find that Catholic high schools substantially increase the probability of graduating from high school and, more tentatively, attending college.
Abstract: In this paper we measure the effect of Catholic high school attendance on educational attainment and test scores. Because we do not have a good instrumental variable for Catholic school attendance, we develop new estimation methods based on the idea that the amount of selection on the observed explanatory variables in a model provides a guide to the amount of selection on the unobservables. We also propose an informal way to assess selectivity bias based on measuring the ratio of selection on unobservables to selection on observables that would be required if one is to attribute the entire effect of Catholic school attendance to selection bias. We use our methods to estimate the effect of attending a Catholic high school on a variety of outcomes. Our main conclusion is that Catholic high schools substantially increase the probability of graduating from high school and, more tentatively, attending college. We find little evidence of an effect on test scores.
2,411 citations
TL;DR: Estimation of transcripts encoding selected hypothalamic peptides associated with energy balance was attenuated in the Clock mutant mice, suggesting that the circadian clock gene network plays an important role in mammalian energy balance.
Abstract: The CLOCK transcription factor is a key component of the molecular circadian clock within pacemaker neurons of the hypothalamic suprachiasmatic nucleus. We found that homozygous Clock mutant mice have a greatly attenuated diurnal feeding rhythm, are hyperphagic and obese, and develop a metabolic syndrome of hyperleptinemia, hyperlipidemia, hepatic steatosis, hyperglycemia, and hypoinsulinemia. Expression of transcripts encoding selected hypothalamic peptides associated with energy balance was attenuated in the Clock mutant mice. These results suggest that the circadian clock gene network plays an important role in mammalian energy balance.
2,241 citations
TL;DR: The improved therapeutic index and elimination of corticosteroid premedication required for solvent-based taxanes make the novel albumin-bound paclitaxel ABI-007 an important advance in the treatment of MBC.
Abstract: Purpose ABI-007, the first biologically interactive albumin-bound paclitaxel in a nanameter particle, free of solvents, was compared with polyethylated castor oil–based standard paclitaxel in patients with metastatic breast cancer (MBC). This phase III study was performed to confirm preclinical studies demonstrating superior efficacy and reduced toxicity of ABI-007 compared with standard paclitaxel. Patients and Methods Patients were randomly assigned to 3-week cycles of either ABI-007 260 mg/m2 intravenously without premedication (n = 229) or standard paclitaxel 175 mg/m2 intravenously with premedication (n = 225). Results ABI-007 demonstrated significantly higher response rates compared with standard paclitaxel (33% v 19%, respectively; P = .001) and significantly longer time to tumor progression (23.0 v 16.9 weeks, respectively; hazard ratio = 0.75; P = .006). The incidence of grade 4 neutropenia was significantly lower for ABI-007 compared with standard paclitaxel (9% v 22%, respectively; P < .001) de...
TL;DR: In this paper, monetary policy and the private sector behavior of the US economy are modeled as a time varying structural vector autoregression, where the sources of time variation are both the coefficients and the variance covariance matrix of the innovations.
Abstract: Monetary policy and the private sector behavior of the US economy are modeled as a time varying structural vector autoregression, where the sources of time variation are both the coefficients and the variance covariance matrix of the innovations. The paper develops a new, simple modeling strategy for the law of motion of the variance covariance matrix and proposes an efficient Markov chain Monte Carlo algorithm for the model likelihood/posterior numerical evaluation. The main empirical conclusions are: 1) both systematic and non-systematic monetary policy have changed during the last forty years. In particular, systematic responses of the interest rate to inflation and unemployment exhibit a trend toward a more aggressive behavior, despite remarkable oscillations; 2) this has had a negligible effect on the rest of the economy. The role played by exogenous non-policy shocks seems more important than interest rate policy in explaining the high inflation and unemployment episodes in recent US economic history.
TL;DR: It is found that the worldwide air transportation network is a scale-free small-world network, and it is demonstrated that the most connected cities are not necessarily the most central, resulting in anomalous values of the centrality.
Abstract: We analyze the global structure of the worldwide air transportation network, a critical infrastructure with an enormous impact on local, national, and international economies. We find that the worldwide air transportation network is a scale-free small-world network. In contrast to the prediction of scale-free network models, however, we find that the most connected cities are not necessarily the most central, resulting in anomalous values of the centrality. We demonstrate that these anomalies arise because of the multicommunity structure of the network. We identify the communities in the air transportation network and show that the community structure cannot be explained solely based on geographical constraints and that geopolitical considerations have to be taken into account. We identify each city's global role based on its pattern of intercommunity and intracommunity connections, which enables us to obtain scale-specific representations of the network.
TL;DR: The overall diagnostic accuracy of digital and film mammography as a means of screening for breast cancer is similar, but digital mammography is more accurate in women under the age of 50 years, women with radiographically dense breasts, and premenopausal or perimenopausal women.
Abstract: background Film mammography has limited sensitivity for the detection of breast cancer in women with radiographically dense breasts. We assessed whether the use of digital mammography would avoid some of these limitations. methods A total of 49,528 asymptomatic women presenting for screening mammography at 33 sites in the United States and Canada underwent both digital and film mammography. All relevant information was available for 42,760 of these women (86.3 percent). Mammograms were interpreted independently by two radiologists. Breast-cancer status was ascertained on the basis of a breast biopsy done within 15 months after study entry or a follow-up mammogram obtained at least 10 months after study entry. Receiver-operating-characteristic (ROC) analysis was used to evaluate the results. results In the entire population, the diagnostic accuracy of digital and film mammography was similar (difference between methods in the area under the ROC curve, 0.03; 95 percent confidence interval, i0.02 to 0.08; P=0.18). However, the accuracy of digital mammography was significantly higher than that of film mammography among women under the age of 50 years (difference in the area under the curve, 0.15; 95 percent confidence interval, 0.05 to 0.25; P=0.002), women with heterogeneously dense or extremely dense breasts on mammography (difference, 0.11; 95 percent confidence interval, 0.04 to 0.18; P=0.003), and premenopausal or perimenopausal women (difference, 0.15; 95 percent confidence interval, 0.05 to 0.24; P=0.002). conclusions The overall diagnostic accuracy of digital and film mammography as a means of screening for breast cancer is similar, but digital mammography is more accurate in women under the age of 50 years, women with radiographically dense breasts, and premenopausal or perimenopausal women. (clinicaltrials.gov number, NCT00008346.)
TL;DR: These data definitively implicate perturbation of TGFβ signaling in many common human phenotypes, including craniosynostosis, cleft palate, arterial aneurysms, congenital heart disease and mental retardation, and suggest that comprehensive mechanistic insight will require consideration of both primary and compensatory events.
Abstract: We report heterozygous mutations in the genes encoding either type I or type II transforming growth factor β receptor in ten families with a newly described human phenotype that includes widespread perturbations in cardiovascular, craniofacial, neurocognitive and skeletal development. Despite evidence that receptors derived from selected mutated alleles cannot support TGFβ signal propagation, cells derived from individuals heterozygous with respect to these mutations did not show altered kinetics of the acute phase response to administered ligand. Furthermore, tissues derived from affected individuals showed increased expression of both collagen and connective tissue growth factor, as well as nuclear enrichment of phosphorylated Smad2, indicative of increased TGFβ signaling. These data definitively implicate perturbation of TGFβ signaling in many common human phenotypes, including craniosynostosis, cleft palate, arterial aneurysms, congenital heart disease and mental retardation, and suggest that comprehensive mechanistic insight will require consideration of both primary and compensatory events.
TL;DR: Analysis of the resulting networks in different tasks shows that the distribution of functional connections, and the probability of finding a link versus distance are both scale-free and the characteristic path length is small and comparable with those of equivalent random networks.
Abstract: Functional magnetic resonance imaging is used to extract functional networks connecting correlated human brain sites. Analysis of the resulting networks in different tasks shows that (a) the distribution of functional connections, and the probability of finding a link versus distance are both scale-free, (b) the characteristic path length is small and comparable with those of equivalent random networks, and (c) the clustering coefficient is orders of magnitude larger than those of equivalent random networks. All these properties, typical of scale-free small-world networks, reflect important functional information about brain states.
TL;DR: Pregnant women should be screened for bacteriuria by urine culture at least once in early pregnancy and they should be treated if the results are positive, and the duration of antimicrobial therapy should be limited.
Abstract: 1. The diagnosis of asymptomatic bacteriuria should be based on results of culture of a urine specimen collected in a manner that minimizes contamination (A-II) (table 1). • For asymptomatic women, bacteriuria is defined as 2 consecutive voided urine specimens with isolation of the same bacterial strain in quantitative counts 10 cfu/mL (B-II). • A single, clean-catch voided urine specimen with 1 bacterial species isolated in a quantitative count 10 cfu/mL identifies bacteriuria in men (BIII). • A single catheterized urine specimen with 1 bacterial species isolated in a quantitative count 10 cfu/mL identifies bacteriuria in women or men (A-II). 2. Pyuria accompanying asymptomatic bacteriuria is not an indication for antimicrobial treatment (A-II). 3. Pregnant women should be screened for bacteriuria by urine culture at least once in early pregnancy, and they should be treated if the results are positive (A-I). • The duration of antimicrobial therapy should be
TL;DR: Conventional treatment would have low removal of many EDC/PPCPs, while addition of PAC and/or ozone could substantially improve their removals, and existing strategies that predict relative removal of herbicides, pesticides, and other organic pollutants can be directly applied.
Abstract: The potential occurrence of endocrine-disrupting compounds (EDCs) as well as pharmaceuticals and personal care products (PPCPs) in drinking water supplies raises concern over the removal of these compounds by common drinking water treatment processes. Three drinking water supplies were spiked with 10 to 250 ng/L of 62 different EDC/PPCPs; one model water containing an NOM isolate was spiked with 49 different EDC/PPCPs. Compounds were detected by LC/MS/MS or GC/MS/MS. These test waters were subjected to bench-scale experimentation to simulate individual treatment processes in a water treatment plant (WTP). Aluminum sulfate and ferric chloride coagulants or chemical lime softening removed some polyaromatic hydrocarbons (PAHs) but removed 98% of GC/MS/MS compounds (more volatile) and 10% to >95% of LC/MS/MS compounds (more polar); higher PAC dosages improved EDC/PPCP removal. EDC/PPCP per...
TL;DR: This article found evidence consistent with small banks being better able to collect and act on soft information than large banks, and that large banks are less willing to lend to informationally "difficult" credits, such as firms with no financial records.
TL;DR: In this work, dark-field microscopy is used to observe a new plasmon resonance effect for a single silver nanocube in which the plAsmon line shape has two distinct peaks when the particles are located on a glass substrate.
Abstract: In this work, we use dark-field microscopy to observe a new plasmon resonance effect for a single silver nanocube in which the plasmon line shape has two distinct peaks when the particles are located on a glass substrate. The dependence of the resonance on nanocube size and shape is characterized, and it is found that the bluer peak has a higher figure of merit for chemical sensing applications than that for other particle shapes that have been studied previously. Comparison of the measured results with finite difference time domain (FDTD) electrodynamics calculations enables us to confirm the accuracy of our spectral assignments.
TL;DR: In this article, the authors focus on how the Internet has impacted the process of collaborative innovation and suggest that firms can use these capabilities to engage customers in collaborative product innovation through a variety of Internet-based mechanisms.
University of Cologne1, Laboratory of Molecular Biology2, Wellcome Trust Sanger Institute3, Baylor College of Medicine4, University of California, San Diego5, Northwestern University6, University of Tsukuba7, Ludwig Maximilian University of Munich8, University of Cambridge9, Hokkaido University10, Pasteur Institute11, University of York12, National Institute of Genetics13, University of Tokyo14, Princeton University15, University of Dundee16
TL;DR: A proteome-based phylogeny shows that the amoebozoa diverged from the animal–fungal lineage after the plant–animal split, but Dictyostelium seems to have retained more of the diversity of the ancestral genome than have plants, animals or fungi.
Abstract: The social amoebae are exceptional in their ability to alternate between unicellular and multicellular forms. Here we describe the genome of the best-studied member of this group, Dictyostelium discoideum. The gene-dense chromosomes of this organism encode approximately 12,500 predicted proteins, a high proportion of which have long, repetitive amino acid tracts. There are many genes for polyketide synthases and ABC transporters, suggesting an extensive secondary metabolism for producing and exporting small molecules. The genome is rich in complex repeats, one class of which is clustered and may serve as centromeres. Partial copies of the extrachromosomal ribosomal DNA (rDNA) element are found at the ends of each chromosome, suggesting a novel telomere structure and the use of a common mechanism to maintain both the rDNA and chromosomal termini. A proteome-based phylogeny shows that the amoebozoa diverged from the animal-fungal lineage after the plant-animal split, but Dictyostelium seems to have retained more of the diversity of the ancestral genome than have plants, animals or fungi.
TL;DR: In this article, a model of preferences over acts is proposed and axiomatize, such that the decision maker will preference act f to act g if and only if Eμφ (Eπu ◦ f) ≥ Eπu g, where E is the expectation operator, u is a vN-M utility function, φ is an increasing transformation, and μ is a subjective probability over the set Π of probability measures π that thedecision maker thinks are relevant given his subjective information.
Abstract: We propose and axiomatize a model of preferences over acts such that the decision maker
prefers act f to act g if and only if Eμφ (Eπu ◦ f) ≥ Eμφ (Eπu ◦ g), where E is the
expectation operator, u is a vN-M utility function, φ is an increasing transformation,
and μ is a subjective probability over the set Π of probability measures π that the
decision maker thinks are relevant given his subjective information. A key feature of our
model is that it achieves a separation between ambiguity, identified as a characteristic
of the decision maker’s subjective information, and ambiguity attitude, a characteristic
of the decision maker’s tastes. We show that attitudes towards risk are characterized
by the shape of u, as usual, while attitudes towards ambiguity are characterized by the
shape of φ. We also derive φ (x) = −1
α
e−αx as the special case of constant ambiguity
aversion. Ambiguity itself is defined behaviorally and is shown to be characterized by
properties of the subjective set of measures Π. This characterization of ambiguity is
formally related to the definitions of subjective ambiguity advanced by Epstein-Zhang
(2001) and Ghirardato-Marinacci (2002). One advantage of this model is that the welldeveloped
machinery for dealing with risk attitudes can be applied as well to ambiguity
attitudes. The model is also distinct from many in the literature on ambiguity in that
allows smooth, rather than kinked, indifference curves. This leads to different behavior
and improved tractability, while still sharing the main features (e.g., Ellsberg’s Paradox,
etc.). The Maxmin EU model (e.g., Gilboa and Schmeidler (1989)) with a given set of
measures may be seen as an extreme case of our model with infinite ambiguity aversion.
Two illustrative applications to portfolio choice are offered.
University of Florida1, Duke University2, Harvard University3, University of Cincinnati4, University of Michigan5, Johns Hopkins University6, University of North Carolina at Chapel Hill7, University of California, Los Angeles8, University of Texas Southwestern Medical Center9, University of Minnesota10, Mayo Clinic11, Ohio State University12, Northwestern University13, University of Calgary14, University of Kentucky15, Cleveland Clinic16, Vanderbilt University17, University of Alabama18, Case Western Reserve University19, University of Washington20, University of California, San Francisco21, University of Wisconsin-Madison22
TL;DR: Therapy to reduce volume overload during hospitalization for heart failure led to marked improvement in signs and symptoms of elevated filling pressures with or without the PAC, which reached significance for the time trade-off at all time points after randomization.
Abstract: Context Pulmonary artery catheters (PACs) have been used to guide therapy in multiple settings, but recent studies have raised concerns that PACs may lead to increased mortality in hospitalized patients. Objective To determine whether PAC use is safe and improves clinical outcomes in patients hospitalized with severe symptomatic and recurrent heart failure. Design, setting, and participants The Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) was a randomized controlled trial of 433 patients at 26 sites conducted from January 18, 2000, to November 17, 2003. Patients were assigned to receive therapy guided by clinical assessment and a PAC or clinical assessment alone. The target in both groups was resolution of clinical congestion, with additional PAC targets of a pulmonary capillary wedge pressure of 15 mm Hg and a right atrial pressure of 8 mm Hg. Medications were not specified, but inotrope use was explicitly discouraged. Main outcome measures The primary end point was days alive out of the hospital during the first 6 months, with secondary end points of exercise, quality of life, biochemical, and echocardiographic changes. Results Severity of illness was reflected by the following values: average left ventricular ejection fraction, 19%; systolic blood pressure, 106 mm Hg; sodium level, 137 mEq/L; urea nitrogen, 35 mg/dL (12.40 mmol/L); and creatinine, 1.5 mg/dL (132.6 micromol/L). Therapy in both groups led to substantial reduction in symptoms, jugular venous pressure, and edema. Use of the PAC did not significantly affect the primary end point of days alive and out of the hospital during the first 6 months (133 days vs 135 days; hazard ratio [HR], 1.00 [95% confidence interval {CI}, 0.82-1.21]; P = .99), mortality (43 patients [10%] vs 38 patients [9%]; odds ratio [OR], 1.26 [95% CI, 0.78-2.03]; P = .35), or the number of days hospitalized (8.7 vs 8.3; HR, 1.04 [95% CI, 0.86-1.27]; P = .67). In-hospital adverse events were more common among patients in the PAC group (47 [21.9%] vs 25 [11.5%]; P = .04). There were no deaths related to PAC use, and no difference for in-hospital plus 30-day mortality (10 [4.7%] vs 11 [5.0%]; OR, 0.97 [95% CI, 0.38-2.22]; P = .97). Exercise and quality of life end points improved in both groups with a trend toward greater improvement with the PAC, which reached significance for the time trade-off at all time points after randomization. Conclusions Therapy to reduce volume overload during hospitalization for heart failure led to marked improvement in signs and symptoms of elevated filling pressures with or without the PAC. Addition of the PAC to careful clinical assessment increased anticipated adverse events, but did not affect overall mortality and hospitalization. Future trials should test noninvasive assessments with specific treatment strategies that could be used to better tailor therapy for both survival time and survival quality as valued by patients.
TL;DR: Fast-food consumption has strong positive associations with weight gain and insulin resistance, suggesting that fast food increases the risk of obesity and type 2 diabetes.
TL;DR: In this article, the relative impact of service provider expertise, product performance, firm reputation, satisfaction, and similarity in influencing customer's perception of these dimensions of trust in a service provider is examined.
TL;DR: In this article, the authors make theoretical comparisons among five coefficients (Cronbach's α, Revelle's β, McDonald's ω� h�, and two alternative conceptualizations of reliability) and demonstrate formally their nonequivalence.
Abstract: We make theoretical comparisons among five coefficients—Cronbach’s α, Revelle’s β, McDonald’s ω
h
, and two alternative conceptualizations of reliability. Though many end users and psychometricians alike may not distinguish among these five coefficients, we demonstrate formally their nonequivalence. Specifically, whereas there are conditions under which α, β, and ω
h
are equivalent to each other and to one of the two conceptualizations of reliability considered here, we show that equality with this conceptualization of reliability and between α and ω
h
holds only under a highly restrictive set of conditions and that the conditions under which β equals ω
h
are only somewhat more general. The nonequivalence of α, β, and ω
h
suggests that important information about the psychometric properties of a scale may be missing when scale developers and users only report α as is almost always the case
TL;DR: A model for the self-assembly of creative teams that has its basis in three parameters: team size, the fraction of newcomers in new productions, and the tendency of incumbents to repeat previous collaborations is proposed.
Abstract: Agents in creative enterprises are embedded in networks that inspire, support, and evaluate their work. Here, we investigate how the mechanisms by which creative teams self-assemble determine the structure of these collaboration networks. We propose a model for the self-assembly of creative teams that has its basis in three parameters: team size, the fraction of newcomers in new productions, and the tendency of incumbents to repeat previous collaborations. The model suggests that the emergence of a large connected community of practitioners can be described as a phase transition. We find that team assembly mechanisms determine both the structure of the collaboration network and team performance for teams derived from both artistic and scientific fields.
TL;DR: In this article, the authors review the motivations for, and recent advances in, new gate dielectric materials for incorporation into organic thin-film transistors (OTFTs) for organic electronics.
Abstract: In this contribution we review the motivations for, and recent advances in, new gate dielectric materials for incorporation into organic thin-film transistors (OTFTs) for organic electronics. After a general introduction to OTFT materials, operating principles, and processing requirements for optimizing low-cost organic electronics, this review focuses on three classes of OTFT-compatible dielectrics: i) inorganic (high-k) materials; ii) polymeric materials; and iii) self-assembled mono- and/multilayer materials. The principal goals in this active research area are tunable and reduced OTFT operating voltages, leading to decreased device power consumption while providing excellent dielectric/insulator properties and efficient low-cost solution-phase processing characteristics.
TL;DR: In this article, single-walled carbon nanotubes (SWCNTs) were functionalized with amino groups via chemical modification of carboxyl groups introduced on the carbon nanotide surface.
Abstract: Single-walled carbon nanotubes (SWCNT) functionalized with amino groups were prepared via chemical modification of carboxyl groups introduced on the carbon nanotube surface. Two different approaches (amide and amine-moieties) were used to produce the amino-functionalized nanotubes. The amino-termination allows further chemistry of the functionalized SWCNTs and makes possible covalent bonding to polymers and biological systems such as DNA and carbohydrates. The functionalization of the SWCNTs was characterized in detail using FTIR and XPS.