bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of a microprocessing-assisted cell-systematic evolution of ligands by exponential enrichment method for human umbilical vein endothelial cells
Authors: Terazono Hideyuki , Kim Hyonchol , Nomura Fumimasa , Yasuda Kenji 
Published: May 2016

Abstract
We developed a microprocessing-assisted technique to select single-strand DNA aptamers that bind to unknown targets on the cell surface by modifying the conventional systematic evolution of ligands by exponential enrichment (cell-SELEX). Our technique involves 1) the specific selection of target-cell-surface-bound aptamers without leakage of intracellular components by trypsinization and 2) cloning of aptamers by microprocessing-assisted picking of single cells using magnetic beads. After cell-SELEX, the enriched aptamers were conjugated with magnetic beads. The aptamer-magnetic beads conjugates attached to target cells were collected individually by microassisted procedures using microneedles under a microscope. After that, the sequences of the collected magnetic-bead-bound aptamers were identified. As a result, a specific aptamer for the surface of target cells, e.g., human umbilical vein endothelial cells (HUVECs), was chosen and its specificity was examined using other cell types, e.g., HeLa cells. The results indicate that this microprocessing-assisted cell-SELEX method for identifying aptamers is applicable in biological research and clinical diagnostics.
Mortality in HIV-infected patients with tuberculosis treated with streptomycin and a two-week intensified regimen: data from an HIV cohort study using inverse probability of treatment weighting
Authors: Alvarez-Uria Gerardo , Midde Manoranjan , Naik Praveen K. 
Published: May 2016

Background.Despite the dramatic scale-up of antiretroviral therapy in low- and middle-income countries, tuberculosis (TB) is still the main cause of death among HIV-infected patients in resource-limited settings. Previous studies in patients with TB meningitis suggest that the use of higher doses of common anti-TB drugs could reduce mortality.Methods.Using clinical data from an HIV cohort study in India, we compared the mortality among HIV-infected patients diagnosed with TB according to the regimen received during the first two weeks of treatment: standard anti-tuberculosis therapy (ATT) (N= 847), intensified ATT (N= 322), and intensified ATT with streptomycin (N= 446). The intensified ATT comprised double dose of rifampicin and substitution of ethambutol with levofloxacin. Multivariate analysis was performed using Cox proportional hazard models and inverse probability of treatment weighting (IPTW) based on propensity scores. Patients with TB meningitis were excluded.Results.The use of intensified ATT alone did not improve survival. However, when streptomycin was added, the use intensified ATT was associated with reduced mortality in Cox models (adjusted hazard ratio 0.72, 95% CI [0.57–0.91]) and after IPTW (hazard ratio 0.77, 95% CI [0.67–0.96]). Other factors associated with improved survival were high serum albumin concentration, high CD4 lymphocyte cell-counts, and high glomerular filtration rates. Factors associated with increased mortality were high urea concentrations, being on antiretroviral therapy at the time of ATT initiation and high BUN/creatinine ratio. In an effect modification analysis, the survival benefits of the intensified ATT with streptomycin disappeared in patients with severe hypoalbuminemia.Conclusion.The results of this study are in accordance with a previous study from our cohort involving patients with TB meningitis, and suggest that an intensified 2-week ATT with streptomycin could reduce mortality in HIV infected patients with TB. As this is an observational study, we should be cautious about our conclusions, but given the high mortality of HIV-related TB, our findings deserve further research.
Forest harvest contribution to Boreal freshwater methyl mercury load
Authors: Kronberg Rose‐Marie , Drott Andreas , Jiskra Martin , Wiederhold Jan G. , Björn Erik , Skyllberg Ulf 
Published: May 2016

AbstractEffects of Boreal forest harvest on mercury (Hg) and methyl mercury (MeHg) soil pools and export by stream runoff were quantified by comparing 10 reference watersheds (REFs) covered by >80 year old Norway spruce (Picea abies Karst.) forests with 10 similar watersheds subjected to clear‐cutting (CCs). While total Hg soil storage did not change, MeHg pools increased six times (p = 0.004) in the organic topsoil 2 years after clear‐cutting. In undulating terrain, situated above the postglacial marine limit (ML) of the ancient Baltic Sea, the mass ratio between flux‐weighted MeHg and dissolved organic carbon (MeHg/DOC) in stream runoff increased 1.8 times (p < 0.004) as a consequence of forest harvest. When recalculated to 100% clear‐cutting of the watershed, the annual MeHg stream export increased 3.8 times (p = 0.047). Below the ML, where the terrain was flatter, neither the MeHg/DOC ratio nor the annual export of MeHg differed between REFs and CCs, likely because of the larger contribution of MeHg exported from peaty soils and small wetlands. The most robust measure, MeHg/DOC, was used to calculate MeHg loadings to Boreal headwaters. If the forest harvest effect lasts 10 years, clear‐cutting increases MeHg runoff by 12–20% in Sweden and 2% in the Boreal zone as a whole. In Sweden, having intensely managed forests, 37% and 56% of MeHg are exported from peatlands and forest soils, respectively, and forest clear‐cutting is adding another 6.6%. In the Boreal zone as a whole peatlands and forests soils contribute with 53% and 46%, respectively, and clear‐cutting is estimated to add another 1.0%. An expected rapid increase in Boreal forest harvest and disturbance urge for inclusion of land use effects in mercury biogeochemical cycling models at different scales.
Low shear velocity in a normal fault system imaged by ambient noise cross correlation: The case of the Irpinia fault zone, Southern Italy
Authors: Vassallo Maurizio , Festa Gaetano , Bobbio Antonella , Serra Marcello 
Published: May 2016

AbstractWe extracted the Green's functions from cross correlation of ambient noise recorded at broadband stations located across the Apennine belt, Southern Italy. Continuous records at 26 seismic stations acquired for 3 years were analyzed. We found the emergence of surface waves in the whole range of the investigated distances (10–140 km) with energy confined in the frequency band 0.04–0.09 Hz. This phase reproduces Rayleigh waves generated by earthquakes in the same frequency range. Arrival time of Rayleigh waves was picked at all the couples of stations to obtain the average group velocity along the path connecting the two stations. The picks were inverted in separated frequency bands to get group velocity maps then used to obtain an S wave velocity model. Penetration depth of the model ranges between 12 and 25 km, depending on the velocity values and on the depth of the interfaces, here associated to strong velocity gradients. We found a low‐velocity anomaly in the region bounded by the two main faults that generated the 1980, M 6.9 Irpinia earthquake. A second anomaly was retrieved in the southeast part of the region and can be ascribed to a reminiscence of the Adria slab under the Apennine Chain.
Future Arctic temperature change resulting from a range of aerosol emissions scenarios
Authors: Wobus Cameron , Flanner Mark , Sarofim Marcus C. , Moura Maria Cecilia P. , Smith Steven J. 
Published: May 2016

AbstractThe Arctic temperature response to emissions of aerosols—specifically black carbon (BC), organic carbon (OC), and sulfate—depends on both the sector and the region where these emissions originate. Thus, the net Arctic temperature response to global aerosol emissions reductions will depend strongly on the blend of emissions sources being targeted. We use recently published equilibrium Arctic temperature response factors for BC, OC, and sulfate to estimate the range of present‐day and future Arctic temperature changes from seven different aerosol emissions scenarios. Globally, Arctic temperature changes calculated from all of these emissions scenarios indicate that present‐day emissions from the domestic and transportation sectors generate the majority of present‐day Arctic warming from BC. However, in all of these scenarios, this warming is more than offset by cooling resulting from SO2 emissions from the energy sector. Thus, long‐term climate mitigation strategies that are focused on reducing carbon dioxide (CO2) emissions from the energy sector could generate short‐term, aerosol‐induced Arctic warming. A properly phased approach that targets BC‐rich emissions from the transportation sector as well as the domestic sectors in key regions—while simultaneously working toward longer‐term goals of CO2 mitigation—could potentially avoid some amount of short‐term Arctic warming.
Background seismicity in Boso Peninsula, Japan: Long‐term acceleration, and relationship with slow slip events
Authors: Reverso T. , Marsan D. , Helmstetter A. , Enescu B. 
Published: May 2016

AbstractSlow slip events (SSEs) in subduction zones can trigger earthquake swarms, especially at shallow depth. The monitoring of seismicity rates has therefore the potential to help detect and characterize SSEs, and transient changes in coupling. However, the relationship between seismicity rate and slow slip rate during a SSE is unknown and made complicated by aftershock triggering within the swarm. Here we propose to complement geodetic methods with an objective measure of the seismicity rate that is directly associated with changes in slip rate. We show that this measure, applied to known occurrences of SSEs in the Boso area, Japan, yields an estimate, albeit indirect, of their seismic moment, hence their slip rate. We finally prove that the background rate in Boso has been accelerating since 1990; this explains previous observations of the shortening of the recurrence time between SSEs in Boso, that clearly predate the 2011 Mw9.0 Tohoku‐Oki earthquake.
Response of lightning NOx emissions and ozone production to climate change: Insights from the Atmospheric Chemistry and Climate Model Intercomparison Project
Authors: Finney D. L. , Doherty R. M. , Wild O. , Young P. J. , Butler A. 
Published: May 2016

AbstractResults from an ensemble of models are used to investigate the response of lightning nitrogen oxide emissions to climate change and the consequent impacts on ozone production. Most models generate lightning using a parameterization based on cloud top height. With this approach and a present‐day global emission of 5 TgN, we estimate a linear response with respect to changes in global surface temperature of +0.44 ± 0.05 TgN K−1. However, two models using alternative approaches give +0.14 and −0.55 TgN K−1 suggesting that the simulated response is highly dependent on lightning parameterization. Lightning NOx is found to have an ozone production efficiency of 6.5 ± 4.7 times that of surface NOx sources. This wide range of efficiencies across models is partly due to the assumed vertical distribution of the lightning source and partly to the treatment of nonmethane volatile organic compound (NMVOC) chemistry. Careful consideration of the vertical distribution of emissions is needed, given its large influence on ozone production.
Flux transfer event observation at Saturn's dayside magnetopause by the Cassini spacecraft
Authors: Jasinski Jamie M. , Slavin James A. , Arridge Christopher S. , Poh Gangkai , Jia Xianzhe , Sergis Nick , Coates Andrew J. , Jones Geraint H. , Waite J. Hunter 
Published: May 2016

AbstractWe present the first observation of a flux rope at Saturn's dayside magnetopause. This is an important result because it shows that the Saturnian magnetopause is conducive to multiple X‐line reconnection and flux rope generation. Minimum variance analysis shows that the magnetic signature is consistent with a flux rope. The magnetic observations were well fitted to a constant‐α force‐free flux rope model. The radius and magnetic flux content of the rope are estimated to be 4600–8300 km and 0.2–0.8 MWb, respectively. Cassini also observed five traveling compression regions (remote signatures of flux ropes), in the adjacent magnetosphere. The magnetic flux content is compared to other estimates of flux opening via reconnection at Saturn.
Designing variable ocean model resolution based on the observed ocean variability
Authors: Sein Dmitry V. , Danilov Sergey , Biastoch Arne , Durgadoo Jonathan V. , Sidorenko Dmitry , Harig Sven , Wang Qiang 
Published: May 2016

AbstractIf unstructured meshes are refined to locally represent eddy dynamics in ocean circulation models, a practical question arises on how to vary the resolution and where to deploy the refinement. We propose to use the observed sea surface height variability as the refinement criterion. We explore the utility of this method (i) in a suite of idealized experiments simulating a wind‐driven double gyre flow in a stratified circular basin and (ii) in simulations of global ocean circulation performed with FESOM. Two practical approaches of mesh refinement are compared. In the first approach the uniform refinement is confined within the areas where the observed variability exceeds a given threshold. In the second one the refinement varies linearly following the observed variability. The resolution is fixed in time. For the double gyre case it is shown that the variability obtained in a high‐resolution reference run can be well captured on variable‐resolution meshes if they are refined where the variability is high and additionally upstream the jet separation point. The second approach of mesh refinement proves to be more beneficial in terms of improvement downstream the midlatitude jet. Similarly, in global ocean simulations the mesh refinement based on the observed variability helps the model to simulate high variability at correct locations. The refinement also leads to a reduced bias in the upper‐ocean temperature.
Row and Column Designs
Authors: Freeman Geoff H. , Williams Emlyn R. 
Published: May 2016

AbstractMany practical experiments are conducted on material arranged in the form of a grid, often a physical two‐dimensional structure such as a glasshouse bench or a field. These two dimensions may then be described asrowsandcolumns. In this article, the discussion of row and column designs is confined to those in which the intersection of any row and any column does not result in more than one experimental unit or plot. The same principles ofexperimental designcan also be used without the physical structure, for example, if there is an existing set of treatments and blocks to which a further set of treatments is to be added. In addition, there are situations where a set of experimental treatments is applied to a number of units, not just once but on several occasions, so that the units are “rows” and the occasions “columns.” Row and column designs with time as one classifying factor are used in, among other areas, animal experimentation, chemical engineering, and market research. An important practical consideration in all these row and column designs is that the effects of rows, columns, and treatments do not interact. If there are suchinteractions, it is still possible to conduct an experiment using rows and columns, and also to carry out a formal analysis of the results. However, the interpretation of the analysis is more difficult, and invalid conclusions may be drawn. Despite these drawbacks, row and column designs have a place in practical experimentation.
Estimating Functions
Authors: Desmond Anthony F. 
Published: May 2016

AbstractThe burgeoning area of estimating functions is reviewed with emphasis on developments in the past two decades or so. The emphasis is on semiparametric methods. Connections with empirical likelihood (seeEmpirical Likelihood) and the bootstrap (seeBootstrap: Theory) are noted, as well as extensions of the theory to stochastic processes. There are numerous application areas where estimating functions have become very influential relatively recently. Econometrics and finance, in particular, have, especially in the past decade or so, discovered the advantages of the estimating function approach. In the statistics arena, applications in biostatistics are particularly important, while survey sampling (seeSurvey Sampling) continues to be a source of methodological problems, which can be tackled via estimating functions.
Robust Estimation of Multivariate Location and Scatter
Authors: Maronna Ricardo A. , Yohai Víctor J. 
Published: May 2016

AbstractClassical methods in multivariate analysis require the estimation of means and covariance matrices. Although the sample mean and covariance matrix are optimal estimates of multivariate location and scatter when the data are multivariate normal, a small fraction of atypical points in the data (outliers) suffices to drastically alter them. This article describes different approaches to the development of substitutes to sample means and covariances that are resistant to outliers.
Profile Analysis
Authors: von Rosen Dietrich 
Published: May 2016

AbstractClassical profile analysis is reviewed. There are three basic hypothesis that are usually considered: test of parallelism, test of equality, and test of flatness. The main theme is to connect these tests within the frame of the analysis of the growth curve model. Moreover, a number of extensions are briefly mentioned including models with random effects, profile analysis within the growth curve model, profile analysis without an assumption of normality, and profile analysis with high‐dimensional data
SERVQUAL
Surveys
Authors: Ograjenšek Irena 
Published: May 2016

Abstract
Perceived service quality is often analyzed using rating scales to assess individual service attributes in questionnaire surveys. The most widely used and most carefully scrutinized rating scale is SERVQUAL. The scale is a result of a systematic ongoing study of service quality that began in 1983. The model defines quality as the difference between customer perceptions and expectations with regard to quality of delivered service. The respondents are asked to answer two sets of questions dealing with the same subject, one set at a general level and one for a service organization in question. Respondents choose from a modified Likert scale that measures intensity of agreement or disagreement with any given statement. Response options range from “strongly agree” and lesser levels of agreement to “neutral” (neither agree nor disagree) and lesser levels of disagreement to “strongly disagree.” Although SERVQUAL has been widely used in business‐to‐business and business‐to‐consumer settings, this does not mean that the scale has not been subjected to reexamination and criticism. There are several well researched and documented objections to SERVQUAL. As a consequence of this critique, various alternative formulations of the service quality model have been suggested. The only one that, to date, seems to outperfom SERVQUAL is SERVPERF, the performance‐only measure of perceived service quality.
Fraud in Clinical Trials
Authors: Buyse Marc , Evans Stephen J. W. 
Published: May 2016

AbstractScientific research has a long history of fraud. In recent decades, the lay press has extensively debated over some cases of fraud in clinical trials, thereby fueling suspicions that fraud is a major problem in clinical research. Furthermore, the boundary between fraud and simple carelessness is often fuzzy, although the former is characterized by a deliberate attempt to deceive. Fraud, in the limited sense of data fabrication or falsification by investigators, is, in all likelihood, a rare phenomenon in clinical trials. Fraud, however, is so much at variance with the ethics of scientific research that any amount of it is deemed utterly unacceptable. Some cases of fraud could actually be prevented by making randomized clinical trials simpler and closer to clinical routine. Even so, any potential fraud must be detected, and statistical methods are especially well suited for this task in the context of multicenter trials. The detection of fraud using statistical techniques rests on the difficulty of fabricating plausible data, particularly in high dimensions, and on the fact that clinical trials are prospective studies that use a unique protocol across a number of investigational centers. A comparison of each center with the others in terms of the distribution of some variables, either taken in isolation (univariate approach) or jointly (multivariate approach), can detect unusual patterns in the data. Central statistical monitoring makes intensive use of such comparisons for an overall assessment of the data consistency across all investigational centers, thereby supporting a risk‐based monitoring strategy of clinical trials.
Trend Analysis
Authors: Harvey Andrew 
Published: May 2016

AbstractThe question of defining a trend is one which has exercised the minds of statisticians for many years. In much of the statistical literature, a trend is conceived of as that part of a series that changes relatively slowly over time. Viewed in terms of prediction, the estimated trend is that part of the series that when extrapolated gives the clearest indication of the future long‐term movements in the series. Trend analysis is best carried out by means of unobserved‐component, or structural, time‐series models. The trend components in structural time‐series models are always set up in such a way that their forecast functions indicate the long‐term movements in the series, and the trend within the series can be obtained by signal extraction methods.
Pattern‐Mixture Model
Authors: Kenward Michael G. 
Published: May 2016

AbstractPattern‐mixture models constitute a class of model for incomplete data and can be represented as a factorization of the joint distribution of the data and missing value process. In such models, units are categorized according to their pattern of missing values, and a different distribution is allowed for the units in each pattern group. Such models are practicable only when the number of such patterns is relatively small, and in practice, they are mainly confined to dropout in longitudinal data with a fixed set of measurement times, for which the number of potential patterns is equal to the number of times. Pattern‐mixture models have the advantage of transparency with respect to the assumptions that are required to allow models to be estimated from incomplete data and, as such, have become widely used as components of sensitivity analyses for missing data problems. There is a variety of ways in which the identifying assumptions can be introduced into a pattern‐mixture model, and the choice is highly dependent on the substantive setting. Estimation and inference for pattern‐mixture models commonly uses multiple imputation, but maximum likelihood and fully Bayesian analyses have also been developed.
Joint Modeling of Longitudinal and Survival Data
Authors: Wu Lang , Yu Tingting 
Published: May 2016

Abstract
In a longitudinal study, we often observe not only longitudinal data but also certain events of interest such as dropouts or deaths or infection of a disease. Usually, the longitudinal data and the event time data (or survival data) are associated. In this case, joint models of longitudinal and survival data are more desirable than separate analyses of either one in the sense that joint models may provide less biased and more efficient statistical inference. There has been a large literature on joint models of longitudinal and survival data in the past few decades. In this article, we provide a brief overview of the basic ideas of joint models, extensions, and recent developments in this field. A simple example is provided for illustration. The objective is to give readers a general picture of joint models, methods for statistical inference, their advantages and limitations, recent developments, and applications.