Showing papers by "University of Colorado Boulder published in 2010"
TL;DR: An overview of the analysis pipeline and links to raw data and processed output from the runs with and without denoising are provided.
Abstract: Supplementary Figure 1 Overview of the analysis pipeline. Supplementary Table 1 Details of conventionally raised and conventionalized mouse samples. Supplementary Discussion Expanded discussion of QIIME analyses presented in the main text; Sequencing of 16S rRNA gene amplicons; QIIME analysis notes; Expanded Figure 1 legend; Links to raw data and processed output from the runs with and without denoising.
28,911 citations
TL;DR: Baron and Kenny's procedure for determining if an independent variable affects a dependent variable through some mediator is so well known that it is used by authors and requested by reviewers almost reflexively.
Abstract: Baron and Kenny’s procedure for determining if an independent variable affects a dependent variable through some mediator is so well known that it is used by authors and requested by reviewers almost reflexively. Many research projects have been terminated early in a research program or later in the review process because the data did not conform to Baron and Kenny’s criteria, impeding theoretical development. While the technical literature has disputed some of Baron and Kenny’s tests, this literature has not diffused to practicing researchers. We present a nontechnical summary of the flaws in the Baron and Kenny logic, some of which have not been previously noted. We provide a decision tree and a step-by-step procedure for testing mediation, classifying its type, and interpreting the implications of findings for theory building and future research.
8,032 citations
4,756 citations
TL;DR: It is found that in direct contrast to the highly differentiated communities of their mothers, neonates harbored bacterial communities that were undifferentiated across multiple body habitats, regardless of delivery mode.
Abstract: Upon delivery, the neonate is exposed for the first time to a wide array of microbes from a variety of sources, including maternal bacteria. Although prior studies have suggested that delivery mode shapes the microbiota's establishment and, subsequently, its role in child health, most researchers have focused on specific bacterial taxa or on a single body habitat, the gut. Thus, the initiation stage of human microbiome development remains obscure. The goal of the present study was to obtain a community-wide perspective on the influence of delivery mode and body habitat on the neonate's first microbiota. We used multiplexed 16S rRNA gene pyrosequencing to characterize bacterial communities from mothers and their newborn babies, four born vaginally and six born via Cesarean section. Mothers' skin, oral mucosa, and vagina were sampled 1 h before delivery, and neonates' skin, oral mucosa, and nasopharyngeal aspirate were sampled <5 min, and meconium <24 h, after delivery. We found that in direct contrast to the highly differentiated communities of their mothers, neonates harbored bacterial communities that were undifferentiated across multiple body habitats, regardless of delivery mode. Our results also show that vaginally delivered infants acquired bacterial communities resembling their own mother's vaginal microbiota, dominated by Lactobacillus, Prevotella, or Sneathia spp., and C-section infants harbored bacterial communities similar to those found on the skin surface, dominated by Staphylococcus, Corynebacterium, and Propionibacterium spp. These findings establish an important baseline for studies tracking the human microbiome's successional development in different body habitats following different delivery modes, and their associated effects on infant health.
3,640 citations
TL;DR: PyNAST as discussed by the authors is a complete reimplementation of NAST, which includes three convenient interfaces: a Mac OS X GUI, a command-line interface and a simple application programming interface (API).
Abstract: Motivation: The Nearest Alignment Space Termination (NAST) tool is commonly used in sequence-based microbial ecology community analysis, but due to the limited portability of the original implementation, it has not been as widely adopted as possible. Python Nearest Alignment Space Termination (PyNAST) is a complete reimplementation of NAST, which includes three convenient interfaces: a Mac OS X GUI, a command-line interface and a simple application programming interface (API).
Results: The availability of PyNAST will make the popular NAST algorithm more portable and thereby applicable to datasets orders of magnitude larger by allowing users to install PyNAST on their own hardware. Additionally because users can align to arbitrary template alignments, a feature not available via the original NAST web interface, the NAST algorithm will be readily applicable to novel tasks outside of microbial community analysis.
Availability: PyNAST is available at http://pynast.sourceforge.net.
Contact: ude.odaroloc@thgink.bor
3,301 citations
TL;DR: The radical-mediated thiol-ene reaction has all the desirable features of a click reaction, being highly efficient, simple to execute with no side products and proceeding rapidly to high yield.
Abstract: Following Sharpless' visionary characterization of several idealized reactions as click reactions, the materials science and synthetic chemistry communities have pursued numerous routes toward the identification and implementation of these click reactions. Herein, we review the radical-mediated thiol-ene reaction as one such click reaction. This reaction has all the desirable features of a click reaction, being highly efficient, simple to execute with no side products and proceeding rapidly to high yield. Further, the thiol-ene reaction is most frequently photoinitiated, particularly for photopolymerizations resulting in highly uniform polymer networks, promoting unique capabilities related to spatial and temporal control of the click reaction. The reaction mechanism and its implementation in various synthetic methodologies, biofunctionalization, surface and polymer modification, and polymerization are all reviewed.
3,229 citations
TL;DR: Soils collected across a long-term liming experiment were used to investigate the direct influence of pH on the abundance and composition of the two major soil microbial taxa, fungi and bacteria, and both the relative abundance and diversity of bacteria were positively related to pH.
Abstract: Soils collected across a long-term liming experiment (pH 4.0-8.3), in which variation in factors other than pH have been minimized, were used to investigate the direct influence of pH on the abundance and composition of the two major soil microbial taxa, fungi and bacteria. We hypothesized that bacterial communities would be more strongly influenced by pH than fungal communities. To determine the relative abundance of bacteria and fungi, we used quantitative PCR (qPCR), and to analyze the composition and diversity of the bacterial and fungal communities, we used a bar-coded pyrosequencing technique. Both the relative abundance and diversity of bacteria were positively related to pH, the latter nearly doubling between pH 4 and 8. In contrast, the relative abundance of fungi was unaffected by pH and fungal diversity was only weakly related with pH. The composition of the bacterial communities was closely defined by soil pH; there was as much variability in bacterial community composition across the 180-m distance of this liming experiment as across soils collected from a wide range of biomes in North and South America, emphasizing the dominance of pH in structuring bacterial communities. The apparent direct influence of pH on bacterial community composition is probably due to the narrow pH ranges for optimal growth of bacteria. Fungal community composition was less strongly affected by pH, which is consistent with pure culture studies, demonstrating that fungi generally exhibit wider pH ranges for optimal growth.
2,966 citations
TL;DR: In this article, a biennial review summarizes much of particle physics using data from previous editions, plus 2158 new measurements from 551 papers, they list, evaluate and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons.
Abstract: This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2158 new measurements from 551 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. Among the 108 reviews are many that are new or heavily revised including those on neutrino mass, mixing, and oscillations, QCD, top quark, CKM quark-mixing matrix, V-ud & V-us, V-cb & V-ub, fragmentation functions, particle detectors for accelerator and non-accelerator physics, magnetic monopoles, cosmological parameters, and big bang cosmology.
2,788 citations
TL;DR: The Spectral and Photometric Imaging REceiver (SPIRE) is the Herschel Space Observatory's sub-millimetre camera and spectrometer as discussed by the authors, which is used for image and spectroscopic data acquisition.
Abstract: The Spectral and Photometric Imaging REceiver (SPIRE), is the Herschel Space Observatory`s submillimetre camera and spectrometer It contains a three-band imaging photometer operating at 250, 350 and 500 mu m, and an imaging Fourier-transform spectrometer (FTS) which covers simultaneously its whole operating range of 194-671 mu m (447-1550 GHz) The SPIRE detectors are arrays of feedhorn-coupled bolometers cooled to 03 K The photometer has a field of view of 4' x 8', observed simultaneously in the three spectral bands Its main operating mode is scan-mapping, whereby the field of view is scanned across the sky to achieve full spatial sampling and to cover large areas if desired The spectrometer has an approximately circular field of view with a diameter of 26' The spectral resolution can be adjusted between 12 and 25 GHz by changing the stroke length of the FTS scan mirror Its main operating mode involves a fixed telescope pointing with multiple scans of the FTS mirror to acquire spectral data For extended source measurements, multiple position offsets are implemented by means of an internal beam steering mirror to achieve the desired spatial sampling and by rastering of the telescope pointing to map areas larger than the field of view The SPIRE instrument consists of a cold focal plane unit located inside the Herschel cryostat and warm electronics units, located on the spacecraft Service Module, for instrument control and data handling Science data are transmitted to Earth with no on-board data compression, and processed by automatic pipelines to produce calibrated science products The in-flight performance of the instrument matches or exceeds predictions based on pre-launch testing and modelling: the photometer sensitivity is comparable to or slightly better than estimated pre-launch, and the spectrometer sensitivity is also better by a factor of 15-2
2,425 citations
TL;DR: Overall survival was significantly improved in those who experienced an acneiform rash of at least grade 2 severity compared with patients with no rash or grade 1 rash, confirming cetuximab plus radiotherapy as an important treatment option in this group of patients.
Abstract: Summary Background Previous results from our phase 3 randomised trial showed that adding cetuximab to primary radiotherapy increased overall survival in patients with locoregionally advanced squamous-cell carcinoma of the head and neck (LASCCHN) at 3 years. Here we report the 5-year survival data, and investigate the relation between cetuximabinduced rash and survival. Methods Patients with LASCCHN of the oropharynx, hypopharynx, or larynx with measurable disease were randomly allocated in a 1:1 ratio to receive either comprehensive head and neck radiotherapy alone for 6–7 weeks or radiotherapy plus weekly doses of cetuximab: 400 mg/m² initial dose, followed by seven weekly doses at 250 mg/m². Randomisation was done with an adaptive minimisation technique to balance assignments across stratifi cation factors of Karnofsky performance score, T stage, N stage, and radiation fractionation. The trial was un-blinded. The primary endpoint was locoregional control, with a secondary endpoint of survival. Following discussions with the US Food and Drug Administration, the dataset was locked, except for queries to the sites about overall survival, before our previous report in 2006, so that an independent review could be done. Analyses were done on an intention-to-treat basis. Following completion of treatment, patients underwent physical examination and radiographic imaging every 4 months for 2 years, and then every 6 months thereafter . The trial is registered at www.ClinicalTrials.gov , number NCT00004227. Findings Patients were randomly assigned to receive radiotherapy with (n=211) or without (n=213) cetuximab, and all patients were followed for survival. Updated median overall survival for patients treated with cetuximab and radiotherapy was 49·0 months (95% CI 32·8–69·5) versus 29·3 months (20·6–41·4) in the radiotherapy-alone group (hazard ratio [HR] 0·73, 95% CI 0·56–0·95; p=0·018). 5-year overall survival was 45·6% in the cetuximab-plus-radiotherapy group and 36·4% in the radiotherapy-alone group. Additionally, for the patients treated with cetuximab, overall survival was signifi cantly improved in those who experienced an acneiform rash of at least grade 2 severity compared with patients with no rash or grade 1 rash (HR 0·49, 0·34–0·72; p=0·002). Interpretation For patients with LASCCHN, cetuximab plus radiotherapy signifi cantly improves overall survival at 5 years compared with radiotherapy alone, confi rming cetuximab plus radiotherapy as an important treatment option in this group of patients. Cetuximab-treated patients with prominent cetuximab-induced rash (grade 2 or above) have better survival than patients with no or grade 1 rash.
1,784 citations
TL;DR: The magnitude of benefit of antidepressant medication compared with placebo increases with severity of depression symptoms and may be minimal or nonexistent, on average, in patients with mild or moderate symptoms.
Abstract: Context Antidepressant medications represent the best established treatment for major depressive disorder, but there is little evidence that they have a specific pharmacological effect relative to pill placebo for patients with less severe depression. Objective To estimate the relative benefit of medication vs placebo across a wide range of initial symptom severity in patients diagnosed with depression. Data Sources PubMed, PsycINFO, and the Cochrane Library databases were searched from January 1980 through March 2009, along with references from meta-analyses and reviews. Study Selection Randomized placebo-controlled trials of antidepressants approved by the Food and Drug Administration in the treatment of major or minor depressive disorder were selected. Studies were included if their authors provided the requisite original data, they comprised adult outpatients, they included a medication vs placebo comparison for at least 6 weeks, they did not exclude patients on the basis of a placebo washout period, and they used the Hamilton Depression Rating Scale (HDRS). Data from 6 studies (718 patients) were included. Data Extraction Individual patient-level data were obtained from study authors. Results Medication vs placebo differences varied substantially as a function of baseline severity. Among patients with HDRS scores below 23, Cohen d effect sizes for the difference between medication and placebo were estimated to be less than 0.20 (a standard definition of a small effect). Estimates of the magnitude of the superiority of medication over placebo increased with increases in baseline depression severity and crossed the threshold defined by the National Institute for Clinical Excellence for a clinically significant difference at a baseline HDRS score of 25. Conclusions The magnitude of benefit of antidepressant medication compared with placebo increases with severity of depression symptoms and may be minimal or nonexistent, on average, in patients with mild or moderate symptoms. For patients with very severe depression, the benefit of medications over placebo is substantial.
TL;DR: A semi-quantitative scoring system that can be applied universally to instability, enzymatic, transgenic and spontaneous OA models may be a useful tool for both new and experienced scorers to sensitively evaluate models and OA mechanisms, and also provide a common paradigm for comparative evaluation across the many groups performing these analyses.
10 Apr 2010
TL;DR: Analysis of microblog posts generated during two recent, concurrent emergency events in North America via Twitter, a popular microblogging service, aims to inform next steps for extracting useful, relevant information during emergencies using information extraction (IE) techniques.
Abstract: We analyze microblog posts generated during two recent, concurrent emergency events in North America via Twitter, a popular microblogging service. We focus on communications broadcast by people who were "on the ground" during the Oklahoma Grassfires of April 2009 and the Red River Floods that occurred in March and April 2009, and identify information that may contribute to enhancing situational awareness (SA). This work aims to inform next steps for extracting useful, relevant information during emergencies using information extraction (IE) techniques.
Stockholm University1, Lawrence Berkeley National Laboratory2, University of California, Berkeley3, Pierre-and-Marie-Curie University4, Colorado College5, University of Colorado Boulder6, University of Utah7, Space Telescope Science Institute8, University of Tokyo9, University of Victoria10, Carnegie Institution for Science11, University of Oxford12, INAF13, Las Cumbres Observatory Global Telescope Network14, University of California, Santa Barbara15, Drexel University16, University of Bonn17, Japan Society for the Promotion of Science18, University of Barcelona19, Texas A&M University20, University of Pittsburgh21
TL;DR: Kowalski et al. as mentioned in this paper reported on work to increase the number of well-measured Type Ia supernovae (SNe Ia) at high redshifts.
Abstract: We report on work to increase the number of well-measured Type Ia supernovae (SNe Ia) at high redshifts. Light curves, including high signal-to-noise HST data, and spectra of six SNe Ia that were discovered during 2001 are presented. Additionally, for the two SNe with z > 1, we present groundbased J-band photometry from Gemini and the VLT. These are among the most distant SNe Ia for which ground based near-IR observations have been obtained. We add these six SNe Ia together with other data sets that have recently become available in the literature to the Union compilation (Kowalski et al. 2008). We have made a number of refinements to the Union analysis chain, the most important ones being the refitting of all light curves with the SALT2 fitter and an improved handling of systematic errors. We call this new compilation, consisting of 557 supernovae, the Union2
TL;DR: This critical review provides insight into emerging venues for application as well as new mechanistic understanding of this exceptional chemistry in its many forms.
Abstract: The merits of thiol-click chemistry and its potential for making new forays into chemical synthesis and materials applications are described Since thiols react to high yields under benign conditions with a vast range of chemical species, their utility extends to a large number of applications in the chemical, biological, physical, materials and engineering fields This critical review provides insight into emerging venues for application as well as new mechanistic understanding of this exceptional chemistry in its many forms (81 references)
Stony Brook University1, University of California, Berkeley2, Macquarie University3, University of California, Davis4, University of North Carolina at Chapel Hill5, University of Wisconsin-Madison6, McGill University7, University of California, Santa Barbara8, University of Bergen9, University of California, Irvine10, University of Florida11, University of Colorado Boulder12, University of Georgia13
TL;DR: The mounting evidence for the importance of niche conservatism to major topics in ecology and conservation and other areas where it may be important but has generally been overlooked is described.
Abstract: The diversity of life is ultimately generated by evolution, and much attention has focused on the rapid evolution of ecological traits. Yet, the tendency for many ecological traits to instead remain similar over time [niche conservatism (NC)] has many consequences for the fundamental patterns and processes studied in ecology and conservation biology. Here, we describe the mounting evidence for the importance of NC to major topics in ecology (e.g. species richness, ecosystem function) and conservation (e.g. climate change, invasive species). We also review other areas where it may be important but has generally been overlooked, in both ecology (e.g. food webs, disease ecology, mutualistic interactions) and conservation (e.g. habitat modification). We summarize methods for testing for NC, and suggest that a commonly used and advocated method (involving a test for phylogenetic signal) is potentially problematic, and describe alternative approaches. We suggest that considering NC: (1) focuses attention on the within-species processes that cause traits to be conserved over time, (2) emphasizes connections between questions and research areas that are not obviously related (e.g. invasives, global warming, tropical richness), and (3) suggests new areas for research (e.g. why are some clades largely nocturnal? why do related species share diseases?).
TL;DR: Based on a review of broad literatures in sociology, economics, and public health, explanations of higher smoking, lower exercise, poorer diet, and excess weight among low-SES persons are classified into nine broad groups that specify related but conceptually distinct mechanisms.
Abstract: The inverse relationships between socioeconomic status (SES) and unhealthy behaviors such as tobacco use, physical inactivity, and poor nutrition have been well demonstrated empirically but encompass diverse underlying causal mechanisms. These mechanisms have special theoretical importance because disparities in health behaviors, unlike disparities in many other components of health, involve something more than the ability to use income to purchase good health. Based on a review of broad literatures in sociology, economics, and public health, we classify explanations of higher smoking, lower exercise, poorer diet, and excess weight among low-SES persons into nine broad groups that specify related but conceptually distinct mechanisms. The lack of clear support for any one explanation suggests that the literature on SES disparities in health and health behaviors can do more to design studies that better test for the importance of the varied mechanisms.
TL;DR: A versatile and powerful tool that allows large-scale comparison of proteome profiles among discrete populations, which will enable the discovery of novel biomarkers in a manner that is unencumbered by the incomplete knowledge of biology, thereby helping to advance the next generation of evidence-based medicine.
Abstract: Background
The interrogation of proteomes (“proteomics”) in a highly multiplexed and efficient manner remains a coveted and challenging goal in biology and medicine.
TL;DR: The ACLED dataset as discussed by the authors is an Armed Conflict Location and Event Dataset (ACLED) covering 50 unstable countries from 1997 through 2010, covering civil war and transnational violent events.
Abstract: This article presents ACLED, an Armed Conflict Location and Event Dataset. ACLED codes the actions of rebels, governments, and militias within unstable states, specifying the exact location and date of battle events, transfers of military control, headquarter establishment, civilian violence, and rioting. In the current version, the dataset covers 50 unstable countries from 1997 through 2010. ACLED’s disaggregation of civil war and transnational violent events allow for research on local level factors and the dynamics of civil and communal conflict. Findings from subnational conflict research challenges conclusions from larger national-level studies. In a brief descriptive analysis, the authors find that, on average, conflict covers 15% of a state’s territory, but almost half of a state can be directly affected by internal wars.
TL;DR: Current progress, the challenges ahead and the new interventions that are being tested to address the unmet need for preventative or curative therapies are described.
Abstract: Type 1 diabetes is an autoimmune disorder afflicting millions of people worldwide. Once diagnosed, patients require lifelong insulin treatment and can experience numerous disease-associated complications. The last decade has seen tremendous advances in elucidating the causes and treatment of the disease based on extensive research both in rodent models of spontaneous diabetes and in humans. Integrating these advances has led to the recognition that the balance between regulatory and effector T cells determines disease risk, timing of disease activation, and disease tempo. Here we describe current progress, the challenges ahead and the new interventions that are being tested to address the unmet need for preventative or curative therapies.
TL;DR: The potential of Fast UniFrac is shown using examples from three data types: Sanger-sequencing studies of diverse free-living and animal-associated bacterial assemblages and from the gut of obese humans as they diet, pyrosequencing data integrated from studies of the human hand and gut, and PhyloChip data from a study of citrus pathogens.
Abstract: Next-generation sequencing techniques, and PhyloChip, have made simultaneous phylogenetic analyses of hundreds of microbial communities possible Insight into community structure has been limited by the inability to integrate and visualize such vast datasets Fast UniFrac overcomes these issues, allowing integration of larger numbers of sequences and samples into a single analysis Its new array-based implementation offers orders of magnitude improvements over the original version New 3D visualization of principal coordinates analysis results, with the option to view multiple coordinate axes simultaneously, provides a powerful way to quickly identify patterns that relate vast numbers of microbial communities We show the potential of Fast UniFrac using examples from three data types: Sanger-sequencing studies of diverse free-living and animal-associated bacterial assemblages and from the gut of obese humans as they diet, pyrosequencing data integrated from studies of the human hand and gut, and PhyloChip data from a study of citrus pathogens We show that a Fast UniFrac analysis using a reference tree recaptures patterns that could not be detected without considering phylogenetic relationships and that Fast UniFrac, coupled with BLAST-based sequence assignment, can be used to quickly analyze pyrosequencing runs containing hundreds of thousands of sequences, showing patterns relating human and gut samples Finally, we show that the application of Fast UniFrac to PhyloChip data could identify well-defined subcategories associated with infection Together, these case studies point the way toward a broad range of applications and show some of the new features of Fast UniFrac
ETH Zurich1, University of Colorado Boulder2, British Geological Survey3, University of Strasbourg4, Institut de Physique du Globe de Paris5, University of Liverpool6, Goddard Space Flight Center7, University of Nantes8, University of Newcastle9, Paris Diderot University10, Centre national de la recherche scientifique11, University of Maryland, Baltimore County12
Abstract: The eleventh generation of the International Geomagnetic Reference Field (IGRF) was adopted in December 2009 by the International Association of Geomagnetism and Aeronomy Working Group V-MOD. It updates the previous IGRF generation with a definitive main field model for epoch 2005.0, a main field model for epoch 2010.0, and a linear predictive secular variation model for 2010.0–2015.0. In this note the equations defining the IGRF model are provided along with the spherical harmonic coefficients for the eleventh generation. Maps of the magnetic declination, inclination and total intensity for epoch 2010.0 and their predicted rates of change for 2010.0–2015.0 are presented. The recent evolution of the South Atlantic Anomaly and magnetic pole positions are also examined.
University of British Columbia1, California Institute of Technology2, University of California, Davis3, University of Oxford4, University of California, Los Angeles5, College of DuPage6, University of Los Andes7, University of California, Santa Barbara8, Guilford College9, Providence Health Care10, Washington University in St. Louis11, Florida State University12, University of Colorado Boulder13, Boise State University14
TL;DR: This article found that participation in a world religion is associated with fairness, although not across all measures, and that market integration positively correlates with fairness while community size positively covaries with punishment.
Abstract: Large-scale societies in which strangers regularly engage in mutually beneficial transactions are puzzling. The evolutionary mechanisms associated with kinship and reciprocity, which underpin much of primate sociality, do not readily extend to large unrelated groups. Theory suggests that the evolution of such societies may have required norms and institutions that sustain fairness in ephemeral exchanges. If that is true, then engagement in larger-scale institutions, such as markets and world religions, should be associated with greater fairness, and larger communities should punish unfairness more. Using three behavioral experiments administered across 15 diverse populations, we show that market integration (measured as the percentage of purchased calories) positively covaries with fairness while community size positively covaries with punishment. Participation in a world religion is associated with fairness, although not across all measures. These results suggest that modern prosociality is not solely the product of an innate psychology, but also reflects norms and institutions that have emerged over the course of human history.
TL;DR: In this article, the authors examine the extent to which RM is associated with firms just meeting earnings benchmarks, and examine how RM affects subsequent operating performance, concluding that real activities manipulation is more likely to influence the output of the accounting system than accruals management.
Abstract: Earnings management can be classified into two categories: accruals management and real activities manipulation (RM). Accruals management involves within generally accepted accounting principles (GAAP) accounting choices that try to ‘‘obscure’’ or ‘‘mask’’ true economic performance (Dechow and Skinner 2000). RM occurs when managers undertake actions that change the timing or structuring of an operation, investment, and ⁄or financing transaction in an effort to influence the output of the accounting system. Schipper (1989, 92) includes RM in her definition of earnings management and describes earnings management as ‘‘a purposeful intervention in the external financial reporting process, with the intention of obtaining some private gain...[a] minor extension of this definition would encompass ‘real’ earnings management, accomplished by timing investment or financing decision to alter reported earnings or some subset of it.’’ This paper examines the extent to which RM is associated with firms just meeting earnings benchmarks. Then, I examine the extent to which RM affects subsequent operating performance. Accruals management is not accomplished by changing the underlying operating activities of the firm, but through the choice of accounting methods used to represent those activities. In contrast, RM involves changing the firm’s underlying operations in an effort to boost current-period earnings. Both types of earnings management involve managers’ attempts to increase ⁄decrease earnings; however, one type affects operations and the
TL;DR: The new era of anti-inflammatory agents includes "biologicals" such as anticytokine therapies and small molecules that block the activity of kinases and small RNAs.
State University of New York System1, University of California, Davis2, University of Colorado Boulder3, Massachusetts Institute of Technology4, California Institute of Technology5, Earth System Research Laboratory6, Carnegie Mellon University7, Paul Scherrer Institute8, Weizmann Institute of Science9
TL;DR: In this article, the authors present results from the factor analysis of 43 AMS datasets (27 of the datasets are reanalyzed in this work) and provide a holistic overview of Northern Hemisphere organic aerosol (OA) and its evolution in the atmosphere.
Abstract: . In this study we compile and present results from the factor analysis of 43 Aerosol Mass Spectrometer (AMS) datasets (27 of the datasets are reanalyzed in this work). The components from all sites, when taken together, provide a holistic overview of Northern Hemisphere organic aerosol (OA) and its evolution in the atmosphere. At most sites, the OA can be separated into oxygenated OA (OOA), hydrocarbon-like OA (HOA), and sometimes other components such as biomass burning OA (BBOA). We focus on the OOA components in this work. In many analyses, the OOA can be further deconvolved into low-volatility OOA (LV-OOA) and semi-volatile OOA (SV-OOA). Differences in the mass spectra of these components are characterized in terms of the two main ions m/z 44 (CO2+) and m/z 43 (mostly C2H3O+), which are used to develop a new mass spectral diagnostic for following the aging of OA components in the atmosphere. The LV-OOA component spectra have higher f44 (ratio of m/z 44 to total signal in the component mass spectrum) and lower f43 (ratio of m/z 43 to total signal in the component mass spectrum) than SV-OOA. A wide range of f44 and O:C ratios are observed for both LV-OOA (0.17±0.04, 0.73±0.14) and SV-OOA (0.07±0.04, 0.35±0.14) components, reflecting the fact that there is a continuum of OOA properties in ambient aerosol. The OOA components (OOA, LV-OOA, and SV-OOA) from all sites cluster within a well-defined triangular region in the f44 vs. f43 space, which can be used as a standardized means for comparing and characterizing any OOA components (laboratory or ambient) observed with the AMS. Examination of the OOA components in this triangular space indicates that OOA component spectra become increasingly similar to each other and to fulvic acid and HULIS sample spectra as f44 (a surrogate for O:C and an indicator of photochemical aging) increases. This indicates that ambient OA converges towards highly aged LV-OOA with atmospheric oxidation. The common features of the transformation between SV-OOA and LV-OOA at multiple sites potentially enable a simplified description of the oxidation of OA in the atmosphere. Comparison of laboratory SOA data with ambient OOA indicates that laboratory SOA are more similar to SV-OOA and rarely become as oxidized as ambient LV-OOA, likely due to the higher loadings employed in the experiments and/or limited oxidant exposure in most chamber experiments.
TL;DR: An integrative strategy is used to predict human genes involved in mitochondrial calcium entry based on clues from comparative physiology, evolutionary genomics and organelle proteomics, and finds MICU1 represents the founding member of a set of proteins required for high-capacity mitochondrial calcium uptake.
Abstract: Mitochondrial calcium uptake has a central role in cell physiology by stimulating ATP production, shaping cytosolic calcium transients and regulating cell death. The biophysical properties of mitochondrial calcium uptake have been studied in detail, but the underlying proteins remain elusive. Here we use an integrative strategy to predict human genes involved in mitochondrial calcium entry based on clues from comparative physiology, evolutionary genomics and organelle proteomics. RNA interference against 13 top candidates highlighted one gene, CBARA1, that we call hereafter mitochondrial calcium uptake 1 (MICU1). Silencing MICU1 does not disrupt mitochondrial respiration or membrane potential but abolishes mitochondrial calcium entry in intact and permeabilized cells, and attenuates the metabolic coupling between cytosolic calcium transients and activation of matrix dehydrogenases. MICU1 is associated with the mitochondrial inner membrane and has two canonical EF hands that are essential for its activity, indicating a role in calcium sensing. MICU1 represents the founding member of a set of proteins required for high-capacity mitochondrial calcium uptake. Its discovery may lead to the complete molecular characterization of mitochondrial calcium uptake pathways, and offers genetic strategies for understanding their contribution to normal physiology and disease.
TL;DR: Experimental evidence for exothermic atom-exchange chemical reactions is reported, starting with an optically trapped near–quantum-degenerate gas of polar 40K87Rb molecules prepared in their absolute ground state.
Abstract: How does a chemical reaction proceed at ultralow temperatures? Can simple quantum mechanical rules such as quantum statistics, single partial-wave scattering, and quantum threshold laws provide a clear understanding of the molecular reactivity under a vanishing collision energy? Starting with an optically trapped near-quantum-degenerate gas of polar 40K87Rb molecules prepared in their absolute ground state, we report experimental evidence for exothermic atom-exchange chemical reactions. When these fermionic molecules were prepared in a single quantum state at a temperature of a few hundred nanokelvin, we observed p-wave-dominated quantum threshold collisions arising from tunneling through an angular momentum barrier followed by a short-range chemical reaction with a probability near unity. When these molecules were prepared in two different internal states or when molecules and atoms were brought together, the reaction rates were enhanced by a factor of 10 to 100 as a result of s-wave scattering, which does not have a centrifugal barrier. The measured rates agree with predicted universal loss rates related to the two-body van der Waals length.
INAF1, University of Colorado Boulder2, University College London3, University of Toulouse4, University of Toronto5, Liverpool John Moores University6, California Institute of Technology7, University of Calgary8, European Southern Observatory9, University of Provence10, University of Paris-Sud11, Paris Diderot University12, Katholieke Universiteit Leuven13, University of Bordeaux14, University of Exeter15, University of New South Wales16, University of Leeds17, Spanish National Research Council18, Sapienza University of Rome19, University of Rome Tor Vergata20, Nagoya University21, University of Manchester22, University of Paris23, Jet Propulsion Laboratory24, Cardiff University25, Chinese Academy of Sciences26, Laval University27, University of Helsinki28, Harvard University29, Max Planck Society30, University of Hertfordshire31, University of Cologne32, University of Kent33, Open University34
TL;DR: In this paper, the first results from the science demonstration phase for the Hi-GAL survey, the Herschel key program that will map the inner Galactic plane of the Milky Way in 5 bands, were presented.
Abstract: We present the first results from the science demonstration phase for the Hi-GAL survey, the Herschel key program that will map the inner Galactic plane of the Milky Way in 5 bands. We outline our data reduction strategy and present some science highlights on the two observed 2° × 2° tiles approximately centered at l = 30° and l = 59°. The two regions are extremely rich in intense and highly structured extended emission which shows a widespread organization in filaments. Source SEDs can be built for hundreds of objects in the two fields, and physical parameters can be extracted, for a good fraction of them where the distance could be estimated. The compact sources (which we will call cores' in the following) are found for the most part to be associated with the filaments, and the relationship to the local beam-averaged column density of the filament itself shows that a core seems to appear when a threshold around AV ~ 1 is exceeded for the regions in the l = 59° field; a AV value between 5 and 10 is found for the l = 30° field, likely due to the relatively higher distances of the sources. This outlines an exciting scenario where diffuse clouds first collapse into filaments, which later fragment to cores where the column density has reached a critical level. In spite of core L/M ratios being well in excess of a few for many sources, we find core surface densities between 0.03 and 0.5 g cm-2. Our results are in good agreement with recent MHD numerical simulations of filaments forming from large-scale converging flows.
TL;DR: In this paper, it was shown that yttrium-stabilized zirconia can be sintered in a few seconds at ∼850°C to full density, starting from a green density of 0.5, by the application of a dc electrical field.
Abstract: We show that yttrium-stabilized zirconia can be sintered in a few seconds at ∼850°C to full density, starting from a green density of 0.5, by the application of a dc electrical field (nominally, several hours at 1450°C are needed to complete the sintering process). This finding is explained by the local Joule heating at grain boundaries, which, on the one hand, promotes grain-boundary diffusion (a kinetic effect), while at the same time restricts grain growth (a thermodynamic effect). The smaller grain size and the higher temperature at grain boundaries can then act synergistically to enhance the rate of sintering. These results have a bearing in explaining the widespread spark plasma and microwave-assisted techniques for enhanced sintering.