Does the Scopus author ID suffice to track scientific international mobility? A case study based on Leibniz laureates

In this paper I outline how author identifiers enable to track international mobility of scientists. Authorship systems help to distinguish among similar names and provide information on affiliations and thus countries of stay. This study explores the relation between CV data and Scopus data in regard to tracking international mobility of scientists. To test the consistency and applicability of data on mobility episodes, residence countries as provided in CVs of a set of German scientists were compared against country information in the affiliations of their publications. Therefore, the CVs of Leibniz laureates were coded for the period 1996–2015 and their publications were gathered on the basis of Scopus author ID. Results show that the majority of scientists under study have a single author ID (68.4%). However, there are laureates with so-called ‘split identities’ where more than one author ID exists. Most of them have a dominant author ID that covers the majority of their publications and one or more additional IDs with only a few publications causing these split identities. Recall statistic shows that the use of the dominant author ID of each laureate would result in around 97% of their publication output. In contrast, the precision of Scopus author ID proves to be high. A random sample shows that all publications assigned to a specific author ID relate to a single individual, so that the precision statistic would yield 100%. Further results show that the registry systems ORCID and ResearcherID are no alternatives to Scopus author ID, because a minority of laureates make use of these identifier systems and data is often incomplete. Unlike ORCID and ResearcherID that suffer from a selection bias as those scientists who remain in science maintain their author profiles, Scopus author ID exists for every author publishing in sources covered by Scopus. The comparison of mobility data in Scopus versus CV data shows that bibliometric data is suitable to identify a scientist’s international mobility and appears to be a good solution if there are no CVs available or if they are incomplete. Furthermore, the reasons for inconsistencies in mobility data are discussed. These mainly reside in the lack of co-author affiliations, incomplete CV data, and other minor reasons.     

工业生产过程数据稳定性评价方法的适应性研究

在分析工业生产过程的多形态数据特征基础上,模拟具有不同形态特征、不同稳定性等级的工业生产过程数据,对比分析6种常用方法对不同形态工业生产数据稳定性分析的适应性。研究结果表明,极差法、偏差程度 (z-分数) 法、假设检验p值法、方差法、信息熵法仅适应于部分工业过程数据的稳定性分析,且信息熵法所得的量化指标值与生产过程时间有关;变异系数法具有更大范围的适应性,可定量评价具有典型结构特征的工业生产过程数据稳定性。卷烟制丝生产数据分析结果表明,变异系数法适用于卷烟制丝等工业生产过程的稳定性定量评价。     

Monitoring the Coefficient of Variation Using a Variable Sampling Interval Control Chart

The coefficient of variation (CV) is a quality characteristic that has several applications in applied statistics and is receiving increasing attention in quality control. Few papers have proposed control charts that monitor this normalized measure of dispersion. In this paper, an adaptive Shewhart control chart implementing a variable sampling interval (VSI) strategy is proposed to monitor the CV. Tables are provided for the statistical properties of the VSI CV chart, and a comparison is performed with a Fixed Sampling Rate Shewhart chart for the CV. An example illustrates the use of these charts on real data gathered from a casting process. Copyright © 2012 John Wiley & Sons, Ltd.     

A reproducible and high-throughput HPLC/MS method to separate sarcosine from α- and β-alanine and to quantify sarcosine in human serum and urine

While sarcosine was recently identified as a potential urine biomarker for prostate cancer, further studies have cast doubt on its utility to diagnose this condition. The inconsistent results may be due to the fact that alanine and sarcosine coelute on an HPLC reversed-phase column and the mass spectrometer cannot differentiate between the two isomers, since the same parent/product ions are generally used to measure them. In this study, we developed a high-throughput liquid chromatography-mass spectrometry (LC-MS) method that resolves sarcosine from alanine isomers, allowing its accurate quantification in human serum and urine. Assay reproducibility was determined using the coefficient of variation (CV) and intraclass correlation coefficient (ICC) in serum aliquots from 10 subjects and urine aliquots from 20 subjects across multiple analytic runs. Paired serum/urine samples from 42 subjects were used to evaluate sarcosine serum/urine correlation. Both urine and serum assays gave high sensitivity (limit of quantitation of 5 ng/mL) and reproducibility (serum assay, intra- and interassay CVs < 3% and ICCs > 99%; urine assay, intra-assay CV = 7.7% and ICC = 98.2% and interassay CV = 12.3% and ICC = 94.2%). In conclusion, this high-throughput LC-MS method is able to resolve sarcosine from α- and β-alanine and is useful for quantifying sarcosine in serum and urine samples.     

Variability of the mechanical properties of bone, and its evolutionary consequences

The relative variabilities (coefficient of variation (CV)) of 10 different mechanical properties of compact bone were determined from 2166 measurements. All measures of variability were made on a minimum of four specimens from any bone. Three pre-yield properties had a CV of about 12%. Six post-yield properties had CVs varying from 24 to 46%. Pre-yield properties increase as a function of mineral content, whereas post-yield properties decrease. These differences give insight into mechanical phenomena occurring at different stages during loading. Furthermore, the fact that some properties are more tightly determined than others has implications for the optimum values set by natural selection. This assertion is made more rigorous using a simple mathematical model for the evolutionarily optimal allocation in a trade-off where one property is imprecisely determined. It is argued that in general the optimum will be biased in favour of the more tightly determined properties than would be the case if all properties had the same CV.     

A Comparison of Interaction and Solvent Deposition Mixing

Abstract

The mixing of microingredients with diluents may be conducted by various methods. The purpose of this report is to compare the uniformity of mixing of finely powdered reserpine after mixing by an interactive and a solvent deposition method. Reserpine was used in concentrations of 0.25% with Avicel PH 102 and Sorbit Instant as carrier materials. The uniformity of the mixtures was compared by coefficients of variation (CV) of the content of powder or tablet samples. The dissolution of powder samples was measured in a rotating bottle apparatus. Interactive mixing with Avicel produced samples with larger variation in reserine content compared to solvent deposition. The variation in content was not significantly different when the drug was mixed interactively or by solvent deposition on Sorbit. Smaller coefficients of variation in content were observed for tablet samples compared to powder samples in most cases. The CVs obtained with powder samples for all the mixtures. except for solvent deposition on Avicel, were larger than 5% and would therefore not comply with pharmaceutical content uniformly standards. The CVs for all tablet samples, however, were less than 5%, and based on these results all the mixtures were sufficiently mixed so that the tablets complied with content uniformity standards. The dissolution profiles were not influenced by mixing method.     

International temporary mobility of researchers: a cross-discipline study

The increasing literature addressing international mobility of researchers has repeatedly pointed out the lack of empirical data compiled over the last two decades, jeopardizing progress in the understanding of the characteristics and impacts of such human flows. This paper makes a contribution to the field by exploring the extent to which information obtained from researchers’ electronic curriculum vitae (CV) may be used to study temporary geographical mobility. We exploit a new type of data set—a comprehensive database of electronic CVs—developing a broad set of cross-discipline mobility indicators to assess the dimensions and characteristics of international research visits among a population of over 10,000 researchers. The sample population is made up of PhD holders working in the regional research system of Andalusia, Spain. Information regarding their international research visits over the last four decades is downloaded from CVs contained in the electronic scientific information system of the region. We assess mobility rates and the characteristics of the temporary mobile population. The analysis of visiting patterns shows significant differences in mobility profiles in terms of frequency, duration and destination of visits, across disciplines, career stages and time periods. The study also shows how different definitions of international mobility lead to substantial variations in cross-discipline mobility rates.     

Relative quantification of carboxylic acid metabolites by liquid chromatography-mass spectrometry using isotopic variants of cholamine

Labeling reagents that differ only in their isotopic composition offer a powerful approach to achieve relative quantification between samples by ESI-MS. Heavy and light isotopic forms of cholamine, which contain a positively charged quaternary ammonium group, were synthesized and tested as new labeling reagents for the relative quantification of carboxylic acid-containing metabolites, specifically fatty acids. The positive charge on cholamine ensures that the labeled product is also positively charged under all LC-MS conditions, regardless of mobile-phase pH. This leads to high ionization efficiency and correspondingly high detection sensitivity, demonstrated here for the analysis of fatty acids in positive ion mode ESI-MS after reversed-phase separation under acidic conditions. Good accuracy and precision were obtained by mixing heavy- and light-labeled hydrolyzed egg lipid extracts in different known ratios. The relative quantification results for 10 observed fatty acids had an average absolute error of 4.6% and an average coefficient of variation (CV) of 2.6%. The labeling strategy yielded a median CV of 6% when employed for fatty acid analysis of eggs from chickens fed various dietary supplements.     

A strategy to prevent signal losses, analyte decomposition, and fluctuating carbon contamination bands in surface-enhanced Raman spectroscopy

Signal losses and fluctuating carbon contamination bands are "bottlenecks" in the application of surface-enhanced Raman spectroscopy (SERS) for reliable chemical analysis. They originate mainly from prolonged laser irradiation of the sample during data collection, which causes analyte decomposition and/or loss of the enhancing capabilities of the adsorption site. In this work, a laser illumination/signal collection technique, the "multiple points collection" (MPC) method is introduced to circumvent these problems. The MPC method is based on the use of a pair of galvanic mirrors to scan the laser beam rapidly and steadily across the sample surface. Each position is irradiated for <10 mus, at a rate of approximately 0.5 Hz. The SER spectrum is obtained by summing the signals collected from a large array of non-overlapping sample points. The MPC is compared with the conventional "single point collection" method, in which the laser beam is statically focused onto a particular spot and the scattered signals acquired. The MPC has the following advantages: (1) illumination and collection efficiencies are not compromised, (2) signal losses originating from analyte decomposition and/or alteration of the enhancing capabilities of the adsorption site are avoided, (3) high-quality SER spectra for analytes such as biomolecules and dipicolinic acid (a common marker for bacteria spores) can be easily obtained, and (4) the occurrence of broad amorphous carbon bands and the commonly observed temporal fluctuations in SERS are prevented. The success of the MPC is attributed to the reduction of local sample heating, as the time interval between the laser irradiations of a spot is much longer than the actual irradiation time itself.     

A strategy of plasma protein quantitation by selective reaction monitoring of an intact protein

Immunoassays are used extensively in the quantitative analysis of proteins in plasma, urine, and other biological matrixes to support preclinical and clinical studies. Although immunoassays are both sensitive and rapid, difficulties during development of these assays are compounded by the need to have a specific antibody or antigen to the protein of interest. Furthermore, calibration curves of immunoassays are inherently nonlinear, and the technique often detects many structurally related components in addition to the analyte of interest. We have developed a novel strategy of analyzing protein concentrations in plasma by utilizing 96-well solid-phase extraction and LC-MS/MS detection of the intact protein. This strategy has been successfully applied in method development and assay validation of quantitatively analyzing protein rK5 concentrations in monkey plasma samples. Additional techniques such as precolumn regeneration and column heating were also incorporated into the assay. Total run time for each sample was approximately 15 min. An LLOQ of 99.2 ng/mL from a sample volume of 50 microL, corresponding to only 380 fmol (3.97 ng) of the rK5 analyte being injected onto the analytical column (assuming 100% extraction recovery), was obtained. The validated linear dynamic range was between 99.2 and 52 920.0 ng/mL, with a correlation coefficient (r(2)) ranging from 0.9972 and 0.9994. The intraassay CV for this assay was between 0.6 and 3.8%, and the interassay CV was between 1.7 and 3.2%. Interassay mean accuracies were between 101.5 and 104.7%. The assay has proven rugged and specific and has been employed to generate data in support of preclinical studies. This strategy for rK5 assay could be used for the development of bioanalytical assays to provide preclinical and clinical support for other protein drug candidates and, furthermore, for the validation of biomarkers discovered from proteomic research.     

Screening of target-specific stress-responsive genes for the development of cell-based biosensors using a DNA microarray

In this study, we describe a straightforward strategy to develop whole cell-based biosensors using fusions of the bacterial bioluminescence genes and the promoters from chemically responsive genes within Escherichia coli, in which chemical target-responsive genes were screened by using the information of gene expression data obtained from DNA microarray analysis. Paraquat was used as a model chemical to trigger gene expression changes of E. coli and to show the DNA microarray-assisted development of whole cell-based biosensors. Gene expression data from the DNA microarray were obtained by time course analysis (10, 30, and 60 min) after exposure to paraquat. After clustering gene expression data obtained by time course analysis, a group of highly expressed genes over the all time courses could be classified. Within this group, three genes expressed highly for overall time points were selected and promoters of these genes were used as fusion partners with reporter genes, lux CDABE, to construct whole cell-based biosensors. The constructed biosensors recognized the presence of model inducer, paraquat, and structural analogue chemicals of paraquat with a high specificity, and the results were reconfirmed by using DNA microarray experiments for those structural analogues. This strategy to develop whole cell-based biosensors assisted by DNA microarray information should be useful in general for constructing chemical-specific or stress-specific biosensors with a high-throughput manner.     

Side-sensitive modified group runs charts with and without measurement errors for monitoring the coefficient of variation

The coefficient of variation (CV) is used in process monitoring when the process mean and standard deviation are proportional to each other. In this work, a side-sensitive modified group runs CV (SSMGR CV) chart is proposed for monitoring the process CV. The run length performance of the SSMGR CV chart is compared to those of the existing CV charts in terms of the average and standard deviation of the run length criteria. The SSMGR CV chart is found to outperform the existing CV charts. In addition, the run length performance of the SSMGR CV chart is also evaluated in the presence of measurement errors, as these errors are not only unavoidable in practice but they also affect the sensitivity of a control chart in detecting an out-of-control situation. The results obtained show that the accuracy and precision errors affect the performance of the SSMGR CV chart in detecting an out-of-control situation.     

FTIR spectral analysis of bituminous binders: reproducibility and impact of ageing temperature

This RILEM round robin study with nine participating laboratories investigated bitumen ageing, its effect on chemical properties and its reproducibility. The impact of temperature used for short-term (RTFOT) binder ageing on the combined short- and long-term (PAV) aged samples was investigated; thereby the effect of reduced mixing temperature such as those relevant for warm mix asphalt technologies on long term ageing was examined. Four 70/100 penetration graded bituminous binders from different sources were selected. In addition to the standard RTFOT temperature of 163 °C, two additional temperatures, 143 and 123 °C were used. The Fourier transform infrared spectroscopy (FTIR) analysis was carried out using an integration method which considers the area below the absorbance spectrum around a band maximum using baseline and tangential approaches. A statistical investigation into the reproducibility of FTIR spectra analysis based on the accumulated data was done. To assess the reproducibility, the coefficient of variation (CV) was taken as a benchmark parameter. Carbonyl and sulfoxide indices were calculated using different baseline correction methods and tangential and baseline integration, respectively. It was shown that the tangential method was not influenced by the applied baseline correction. However, in all considered cases, the tangential method led to significantly worse reproducibility (CVs ranging from 20 to 120%) compared to the baseline method. The sulfoxide indices calculated by both methods were not affected by the baseline correction method used. Impacts of changes in the short-term ageing temperature on short- or long-term aged samples could not be found whereas differences between different binder sources could be detected. RTFOT temperature and therefore mix production temperature had a stronger impact on the formation of sulfoxide structures than for carbonyl structures. The findings from this study show the most reproducible of all considered methods when more than one laboratory is providing FTIR data.     

Integrating baseline health status data collection into the process of care.

BACKGROUND: Health status data are an increasingly important component of outcomes assessment and can be used to facilitate quality assessment and improvement efforts. An enormous challenge to the use of health status data among hospitalized patients, however, is collecting baseline data at the time of treatment, an essential component for risk-adjusting subsequent outcomes. The Mid America Heart Institute of Saint Luke's Hospital (Kansas City, Mo), attempted to integrate the collection of health status assessments within the process of performing coronary revascularization. THE DATA COLLECTION STRATEGY: The data collection strategy was developed for each admission portalelective outpatients (admissions for same-day procedures), inpatients, and emergent cases. Health status data were collected on all patients with coronary artery disease who were receiving a percutaneous coronary intervention or coronary artery bypass graft with no disruption to physician scheduling or nursing staff. RESULTS: In general, patients were agreeable to completing the health status survey. Despite initial efforts to educate the hospital staff about the goal and purpose of health status assessment, staff members who were unaware of the uses of these data seemed to minimize their value. Providing examples of how to use these data relative to the staff member's specific occupational role facilitated buy-in for this project. EPILOGUE: After the pilot study, which lasted until June 1999, data were continually collected for 18 months, through August 2000, even with the cessation of external grant funding for this project. Baseline data collection finally stopped, primarily because of a failure to accommodate data collection into the routine flow of patient care by existing nursing staff.     

Optical fiber probe for biomedical Raman spectroscopy

In vitro experiments have demonstrated the ability of Raman spectroscopy to diagnose a wide variety of diseases. Recent in vivo investigations performed with optical fiber probes were promising but generally limited to easily accessible organs, often requiring relatively long collection times. We have implemented an optical design strategy to utilize system throughput fully by characterizing the Raman distribution from tissue. This scheme optimizes collection efficiency, minimizes noise, and has resulted in small-diameter, highly efficient Raman probes that are capable of collecting high-quality data in 1 s. Performance has been tested through simulations and experiments with tissue models and several in vitro tissue types, demonstrating that this new design can advance Raman spectroscopy as a clinically practical technique.     

Variability in surface infrared reflectance of thirteen nitrile rubber gloves at key wavelengths for analysis of captan

The aim of this study was to investigate the surface variability of 13 powder-free, unlined, and unsupported nitrile rubber gloves using attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectrophotometry at key wavelengths for analysis of captan contamination. The within-glove, within-lot, and between-lot variability was measured at 740, 1124, 1252, and 1735 cm(-1), the characteristic captan reflectance minima wavelengths. Three glove brands were assessed after conditioning overnight at relative humidity (RH) values ranging from 2 +/- 1 to 87 +/- 4% and temperatures ranging from -8.6 +/- 0.7 to 59.2 +/- 0.9 degrees C. For all gloves, 1735 cm(-1) provided the lowest background absorbance and greatest potential sensitivity for captan analysis on the outer glove surface: absorbances ranged from 0.0074 +/- 0.0005 (Microflex) to 0.0195 +/- 0.0024 (SafeSkin); average within-glove coefficients of variation (CV) ranged from 2.7% (Best, range 0.9-5.3%) to 10% (SafeSkin, 1.2-17%); within-glove CVs greater than 10% were for one brand (SafeSkin); within-lot CVs ranged from 2.8% (Best N-Dex) to 28% (SafeSkin Blue); and between-lot variation was statistically significant (p < or = 0.05) for all but two SafeSkin lots. The RH had variable effects dependent on wavelength, being minimal at 1735, 1252, and 1124 cm(-1) and highest at 3430 cm(-1) (O-H stretch region). There was no significant effect of temperature conditioning. Substantial within-glove, within-lot, and between-lot variability was observed. Thus, surface analysis using ATR-FT-IR must treat glove brands and lots as different. ATR-FT-IR proved to be a useful real-time analytical tool for measuring glove variability, detecting surface humidity effects, and choosing selective and sensitive wavelengths for analysis of nonvolatile surface contaminants.     

The Scanning Data Collection Strategy for Enhancing the Quality of Electrical Impedance Tomography

This paper addresses a scanning data collection strategy in electrical impedance tomography (EIT) to enhance the quality of an impedance image by expanding the electrode number. This scanning EIT (SEIT) system rotates the electrode pairs at a small angle, and then, the measurement electrodes can scan around the circumference of a phantom tank. The numerical simulations examine the reconstructed result by using a cylindrical model with two conductivity varieties. The experimental results illustrate the reconstruction images with and without the SEIT from 2-D real measurement data. Compared with conventional EIT images, the images reconstructed from the scanning data collection strategy exhibit high resolution and are clearer. This paper provides a feasible configuration to reduce the noise and improve the resolution of the impedance image.     

Multiwalled carbon nanotubes enhance electrochemical properties of titanium to determine in situ bone formation

Multiwalled carbon nanotubes (MWCNTs) enhance osteoblast (bone-forming cell) calcium deposition compared to currently implanted materials (such as titanium). In this study, MWCNTs were grown out of nanopores anodized on titanium (MWCNT-Ti). The electrochemical responses of MWCNT-Ti were investigated in an attempt to ascertain if MWCNT-Ti can serve as novel in situ sensors of bone formation. For this purpose, MWCNT-Ti was subjected to a ferri/ferrocyanide redox couple and its electrochemical behavior measured. Cyclic voltammograms (CVs) showed an enhanced redox potential for the MWCNT-Ti. These redox signals were superior to that obtained with bare unmodified Ti, which did not sense either oxidation or reduction peaks in the CVs. A further objective of this study was to investigate the redox reactions of MWCNT-Ti in a solution of extracellular components secreted by osteoblasts in vitro. It was found that MWCNT-Ti exhibited well-defined and persistent CVs, similar to the ferri/ferrocyanide redox reaction. The higher electrodic performance and electrocatalytic activity of the MWCNT-Ti compared to the bare titanium observed in this study were likely due to the fact that MWCNTs enhanced direct electron transfer and facilitated double-layer effects, leading to a strong redox signal. Thus these results encourage the further study and modification of MWCNT-Ti to sense new bone growth in situ next to orthopedic implants and perhaps monitor other events (such as infection and/or harmful scar tissue formation) to improve the current clinical diagnosis of orthopedic implants.     

气液两相流管道噪声测试

气液两相流管道内气流扰动、气体与液体的扰动产生噪声。利用双通道数据采集器/频谱分析仪对实验管道沿程噪声进行数据采集与处理,得到管道噪声频谱图。改变实验条件,对不同气体流量,不同含液量的管道进行噪声测试。通过对噪声频谱图的数据统计与分析,对管道噪声特性进行总结。通过分析可知,管道噪声检测是确定输气管道是否含液及是否出现液塞的有效方法。