bluuebunny/crossref_metadata_2025_split huggingface dataset:
Step by step: Capturing the dynamics of work team process through relational event sequences
Authors: Schecter Aaron , Pilny Andrew , Leung Alice , Poole Marshall Scott , Contractor Noshir 
Published: November 2017

SummaryThe emergence of group constructs is an unfolding process, whereby actions and interactions coalesce into collective psychological states. Implicitly, there is a connection between these states and the underlying procession of events. The manner in which interactions follow one another over time describe a group's behavior, with different temporal patterns being indicative of different team characteristics. In this study, we explicitly connect event sequences to the process of emergence. We argue that the temporal relationship between events in a sequence will vary depending on the team's psychological outcome. Further, certain patterns of behavior will be repeated at different rates in teams with varying emergent states. To support this approach, we apply a statistical methodology—relational event modeling—for analyzing sequences of interactions that builds on the foundation of social network analysis. Using a dataset comprised of 55 work teams of military personnel engaged in a tactical scenario, we found that individuals who perceived team process (regarding coordination and information sharing) as having different qualities engaged in significantly different patterns of behavior. Our findings indicate that individuals who had a positive perception of process quality were more likely to initiate communication events in a reciprocal, transitive, and decentralized fashion.
Why is your boss making you sick? A longitudinal investigation modeling time‐lagged relations between abusive supervision and employee physical health
Authors: Liang Lindie H. , Hanig Samuel , Evans Rochelle , Brown Douglas J. , Lian Huiwen 
Published: November 2017

SummaryAlthough an abundance of cross‐sectional data have linked abusive supervision with employees' experience of health‐related problems, further research accounting for the temporal dynamics of these variables is needed to establish causality. Furthermore, the process by which abusive supervision relates to subordinate health problems requires greater clarification. In a 1‐year longitudinal cross‐lagged investigation, we sought to test the time‐lagged relationship between abusive supervision and employee physical health; additionally, we test rumination as a cognitive process that mediates this time‐lagged relationship while modeling other relevant social and motivational mediators. Our results indicate that subordinate ruminative thinking about their experiences of abusive supervision mediates the time‐lagged association between abusive supervision and physical health problems. These findings suggest that reducing ruminative thinking may limit the long‐term impact of abusive supervision on employees' physical health.
Role of dexamethasone in the long‐term functional maturation of MSC‐laden hyaluronic acid hydrogels for cartilage tissue engineering
Authors: Kim Minwook , Garrity Sean T. , Steinberg David R. , Dodge George R. , Mauck Robert L. 
Published: November 2017

ABSTRACTThe purpose of study was to investigate the maturation of mesenchymal stem cells (MSC) laden in HA constructs with various combinations of chemically defined medium (CM) components and determine the impact of dexamethasone and serum on construct properties. Constructs were cultured in CM with the addition or withdrawal of media components or were transferred to serum containing media that partially represents an in vivo‐like condition where pro‐inflammatory signals are present. Constructs cultured in CM+ (CM with TGF‐β3) and DEX− (CM+ without dexamethasone) conditions produced robust matrix, while those in ITS/BSA/LA− (CM+ without ITS/BSA/LA) and Serum+ (10% FBS with TGF‐β3) produced little matrix. While construct properties in DEX− were greater than those in CM+ at 4 weeks, properties in CM+ and DEX− reversed by 8 weeks. While construct properties in DEX− were greater than those in CM+ at 4 weeks, the continued absence or removal of dexamethasone resulted in marked GAG loss by 8 weeks. Conversely, the continued presence or new addition of dexamethasone at 4 weeks further improved or maintained construct properties through 8 weeks. Finally, when constructs were converted to Serum (in the continued presence of TGF‐β3 with or without dexamethasone) after pre‐culture in CM+ for 4 weeks, GAG loss was attenuated with addition of dexamethasone. Interestingly, however, collagen content and type was not impacted. In conclusion, dexamethasone influences the functional maturation of MSC‐laden HA constructs, and may help to maintain properties during long‐term culture or with in vivo translation by repressing pro‐inflammatory signals. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1717–1727, 2018.
Frontal plane hip joint loading according to pain severity in people with hip osteoarthritis
Authors: Hall Michelle , Allison Kim , Wrigley Tim V. , Metcalf Ben R. , Pua Yong‐Hao , Van Ginckel Ans , Bennell Kim L. 
Published: November 2017

ABSTRACTThe primary objective was to examine the hip adduction moment during walking in people with hip osteoarthritis (OA) according to pain severity. Sixty‐eight participants with unilateral symptomatic hip OA were included. Pain during walking was assessed on a 5‐point Likert item within the Western Ontario and McMaster Universities Index (no pain = 12; mild pain n = 37; moderate pain n = 19). Measures of the external hip adduction moment (peaks, Nm/BW × BH (%) and impulse, Nm.s/BW × BH (%)) were determined. Other measures included frontal plane hip, pelvis and trunk kinematics, walking speed and peak isometric hip abductor strength. Variables were compared according to pain severity using linear models and biomechanical variables were examined. Participants with moderate pain had a significantly higher second peak hip adduction moment and impulse compared to those with less pain. There was no difference in any measure of hip adduction moment between those with mild pain and no pain. There were no differences in kinematics across pain severity categories. Participants with moderate pain had a significantly slower walking speed compared to participants with mild and no pain. Participants with moderate pain had weaker peak isometric hip abductor strength compared to those with mild pain and no pain. The hip adduction moment during walking, hip abduction strength and walking speed differs according to pain severity during walking in people with hip OA. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1637–1644, 2018.
Authentication of commercial spices based on the similarities between gas chromatographic fingerprints
Authors: Matsushita Takaya , Zhao Jing Jing , Igura Noriyuki , Shimoda Mitsuya 
Published: November 2017

AbstractBACKGROUNDA simple and solvent‐free method was developed for the authentication of commercial spices. The similarities between gas chromatographic fingerprints were measured using similarity indices and multivariate data analyses, as morphological differentiation between dried powders and small spice particles was challenging. The volatile compounds present in 11 spices (i.e. allspice, anise, black pepper, caraway, clove, coriander, cumin, dill, fennel, star anise, and white pepper) were extracted by headspace solid‐phase microextraction, and analysed by gas chromatography–mass spectrometry.RESULTSThe largest 10 peaks were selected from each total ion chromatogram, and a total of 65 volatiles were tentatively identified. The similarity indices (i.e. the congruence coefficients) were calculated using the data matrices of the identified compound relative peak areas to differentiate between two sets of fingerprints. Where pairs of similar fingerprints produced high congruence coefficients (>0.80), distinctive volatile markers were employed to distinguish between these samples. In addition, hierarchical cluster analysis and principal component analysis were performed to visualise the similarity among fingerprints, and the analysed spices were grouped and characterised according to their distinctive major components.CONCLUSIONThis method is suitable for screening unknown spices, and can therefore be employed to evaluate the quality and authenticity of various spices. © 2017 Society of Chemical Industry
l‐Cysteine‐modified silver‐functionalized silica‐based material as an efficient solid‐phase extraction adsorbent for the determination of bisphenol A
Authors: Li Yuanyuan , Zhu Nan , Li Bingxiang , Chen Tong , Ma Yulong , Li Qiang 
Published: November 2017

AbstractA new silver‐functionalized silica‐based material with a core–shell structure based on silver nanoparticle‐coated silica spheres was synthesized, and silver nanoparticles were modified using strongly bound l‐cysteine. l‐Cysteine‐silver@silica was characterized by scanning electron microscopy and FTIR spectroscopy. Then, a solid‐phase extraction method based on l‐cysteine‐silver@silica was developed and successfully used for bisphenol A determination prior to HPLC analysis. The results showed that the l‐cysteine‐silver@silica as an adsorbent exhibited good enrichment capability for bisphenol A, and the maximum adsorption saturation was 20.93 mg/g. Moreover, a short adsorption equilibrium time was obtained due to the presence of silver nanoparticles on the surface of the silica. The extraction efficiencies were then optimized by varying the eluents and pH. Under the optimized conditions, good linearity for bisphenol A was obtained in the range from 0.4 to 4.0 μM (R2 > 0.99) with a low limit of detection (1.15 ng/mL). The spiked recoveries from tap water and milk samples were satisfactory (85–102%) with relative standard deviations below 5.2% (n = 3), which indicated that the method was suitable for the analysis of bisphenol A in complex samples.
Simultaneous quantitative assessment of nine glycosides in tobacco by liquid chromatography–tandem mass spectrometry
Authors: Yuan Yue , Zhou Rong , Li Dongliang , Luo Cheng , Li Guoyou 
Published: November 2017

AbstractA simple and efficient method combining ultrasound‐assisted extraction, the conditions of which were optimized by response surface methodology, with liquid chromatography and tandem mass spectrometry was established and validated for the absolute quantification of nine non‐volatile neutral glycosides originating from tobacco (Nicotiana tobaccum L.) leaves, comprising three phenolic glycosides, one benzanoid glycoside, and five sesquiterpene glycosides within three isomers, originating from tobacco leaves. Factors of extraction time, sample quantity, extraction solvent, liquid chromatographic conditions, and electrospray ionization parameters were carefully investigated to ensure the selectivity and sensitivity of the method. All calibration curves showed excellent coefficients of determination ranging from 0.9940 to 0.9996, within the range of tested concentrations. The limits of detection and quantification were 2.33–25.9 and 7.06–78.5 ng/mL, respectively. Satisfactory values of accuracy were between 80.1 to 107.9% among different sample matrixes. The relative standard deviations of intra‐ and inter‐day analysis were less than 13.7 and 13.0% respectively. The developed method was successfully applied in a pilot study to determine the amounts of the nine endogenous glycosides in real flue‐cured tobacco samples obtained from different habitats in China.
Analysis of emerging organic contaminants in poultry manure by gas chromatography–tandem mass spectrometry
Authors: Aznar Ramón , Albero Beatriz , Pérez Rosa Ana , Sánchez‐Brunete Consuelo , Miguel Esther , Tadeo José L. 
Published: November 2017

AbstractA multiresidue method was developed for the determination of 19 emerging organic contaminants (pharmaceutical drugs, personal care products, and bisphenol A) in poultry manure. Lyophilized samples of manure were extracted by ultrasound‐assisted matrix solid‐phase dispersion and the extracts were analyzed by gas chromatography with tandem mass spectrometry after derivatization. Analysis of spiked poultry manure samples, at levels ranging from 25 to 150 ng/g, gave satisfactory recovery results for all the compounds, with values from 67 to 106%. The developed procedure provided detection limits that ranged from 0.9 to 2.2 ng/g. Finally, the validated method was applied to poultry manure samples collected from 23 poultry farms in Spain. Salicylic acid was found in most of the samples analyzed at levels up to 2501 ng/g, whereas, methyl paraben, orthophenylphenol, ibuprofen, paracetamol, and carbamazepine were detected at levels up to 250 ng/g. Composting of manure showed an important decrease in the levels of the detected contaminants.
Geographic impact evaluation of the quality of Alismatis Rhizoma by untargeted metabolomics and quantitative assay
Authors: Wu Jia , Yang Wenzhi , Pan Huiqin , Yao Shuai , Wu Wanying , Guo Dean 
Published: November 2017

AbstractThe geographic impact on the quality of Alismatis Rhizoma (derived from the tuber of Alisma orientale), a reputable diuretic traditional Chinese medicine, has seldom been evaluated. Here a metabolomics‐driven approach targeting the bioactive protostane triterpenes was developed, by incorporating UHPLC with quadrupole time‐of‐flight mass spectrometry‐based untargeted metabolite profiling and multiple reaction monitoring quantitative assay, to probe the triterpene differences between Alismatis Rhizoma samples collected from Sichuan, Fujian, and Jiangxi Provinces. Following the metabolomics workflows, the samples from Sichuan and Jiangxi displayed distinct differences in their triterpene profiles, whereas those from Fujian showed remarkable intra‐class variation. Twenty‐three triterpenes were identified to contribute most to the differentiated clustering. A sensitive, precise, repeatable, and accurate quantitative assay method was established on a hybrid triple quadrupole‐linear ion trap mass spectrometer to quantify the contents of eight triterpene compounds. Taking into account the metabolomics and quantitation results, alisol B 23‐acetate and alisol A are significantly different in Alismatis Rhizoma from Sichuan and Jiangxi Provinces, and they may have the potential for geographic discrimination. These results illustrate how geographic difference impacts the triterpene chemistry of Alismatis Rhizoma. Metabolomics‐driven chemical comparison is suitable for the quality evaluation of traditional Chinese medicine.
Selective extraction of morphine from biological fluids by magnetic molecularly imprinted polymers and determination using UHPLC with diode array detection
Authors: Ebrahimi Rahmani Mahdiyeh , Ansari Mehdi , Kazemipour Maryam , Nateghi Mohammadreza 
Published: November 2017

AbstractThe determination of morphine concentration in the blood and urine is necessary for patients and recruitment purposes. Herein, a magnetic molecularly imprinted polymer for selective and efficient extraction of morphine from biological samples was synthesized by using a core–shell method. Fe3O4 nanoparticles were coated with SiO2‐NH2. The molecularly imprinted polymer was coated on the Fe3O4/SiO2‐NH2 surface by the copolymerization of methacrylic acid and ethylene glycol dimethacrylate in the presence of morphine as the template molecule. The morphological and magnetic properties of the polymer were investigated. Field‐emission scanning electron microscopy indicated that the prepared magnetic polymer is almost uniform. The saturation magnetization values of Fe3O4 nanoparticles, Fe3O4/SiO2‐NH2, and the magnetic polymer were 48.41, 31.69, and 13.02 emu/g, respectively, indicating that all the particles are superparamagnetic. Kinetics of the adsorption of morphine on magnetic polymer were well described by second‐order kinetic and adsorption processes and well fitted by the Langmuir adsorption isotherm, in which the maximum adsorption capacity was calculated as 28.40 mg/g. The recoveries from plasma and urine samples were in the range of 84.9–105.5 and 94.9–102.8%, respectively. By using the magnetic molecularly imprinted polymer, morphine can selectively, reliably, and in low concentration be determined in biological samples with high‐performance liquid chromatography and UV detection.
Synthesis and chromatographic evaluation of phenyl/tetrazole bonded stationary phase based on thiol‐epoxy ring opening reaction
Authors: Jin Gaowa , Liu Yanming , Yang Fan , Yu Dongping , Yan Jingyu , Zhou Weijia , Guo Zhimou , Zhu Jianhua , Liang Xinmiao 
Published: November 2017

AbstractA silica‐based reversed‐phase stationary phase bonding with phenyl and tetrazole groups was synthesized by thiol‐epoxy ring opening reaction. The bonded groups could not only provide hydrophobic interaction, but also π–π, hydrogen bonding, electrostatic interactions, and so on. The results of characterization with elemental analysis and solid‐state 13C cross‐polarization magic‐angle‐spinning NMR spectroscopy indicated the successful preparation of phenyl/tetrazole sulfoether bonded stationary phase. Chromatographic evaluation revealed that phenyl/tetrazole sulfoether bonded stationary phase behaved well under the reversed‐phase mode. The column parameters (H, S*, A, B, and C) showed different selectivity compared with some typical commercial columns, and it was validated by the separation of estrogen, ginsenoside, alkaloid samples. Based on the different selectivity between phenyl/tetrazole sulfoether bonded stationary phase and C18 columns, phenyl/tetrazole sulfoether bonded stationary phase also showed potential to construct a 2D reversed‐phase liquid chromatography system with C18. And it was verified by the separation of corydalis tuber and curcuma zedoary extracts.
Generic approach to the method development of intact protein separations using hydrophobic interaction chromatography
Authors: Tyteca Eva , De Vos Jelle , Tassi Marco , Cook Ken , Liu Xiaodong , Kaal Erwin , Eeltink Sebastiaan 
Published: November 2017

AbstractWe describe a liquid chromatography method development approach for the separation of intact proteins using hydrophobic interaction chromatography. First, protein retention was determined as function of the salt concentration by isocratic measurements and modeled using linear regression. The error between measured and predicted retention factors was studied while varying gradient time (between 15 and 120 min) and gradient starting conditions, and ranged between 2 and 15%. To reduce the time needed to develop optimized gradient methods for hydrophobic interaction chromatography separations, retention‐time estimations were also assessed based on two gradient scouting runs, resulting in significantly improved retention‐time predictions (average error < 2.5%) when varying gradient time. When starting the scouting gradient at lower salt concentrations (stronger eluent), retention time prediction became inaccurate in contrast to predictions based on isocratic runs. Application of three scouting runs and a nonlinear model, incorporating the effects of gradient duration and mobile‐phase composition at the start of the gradient, provides accurate results (improved fitting compared to the linear solvent‐strength model) with an average error of 1.0% and maximum deviation of –8.3%. Finally, gradient scouting runs and retention‐time modeling have been applied for the optimization of a critical‐pair protein isoform separation encountered in a biotechnological sample.
High‐Temperature Rate Constants for H + Tetramethylsilane and H + Silane and Implications about Structure–Activity Relationships for Silanes
Authors: Peukert S. , Herzler J. , Fikri M. , Schulz C. 
Published: November 2017

ABSTRACTThe shock‐tube technique has been used to investigate the reactions H + SiH4 → H2 + SiH3 (R1) and H + Si(CH3)4 → Si(CH3)3CH2 + H2 (R2) behind reflected shock waves. C2H5I was used as a thermal in situ source for H atoms. For reaction (R1), the experiments covered a temperature range of 1170–1251 K and for (R2) 1227–1320 K. In both cases, the pressures were near 1.5 bar. In these experiments, H atoms were monitored with atomic resonance absorption spectrometry. Fits to the H‐atom temporal concentration profiles applying postulated chemical kinetic reaction mechanisms were used for determining the rate constants k1 and k2. Experimental rate constants were well represented by the Arrhenius equations k1(T) = 2.75 × 10−9 exp(−37.78 kJ mol−1/RT) cm3 s−1 and k2(T) = 1.17 × 10−7 exp(−86.82 kJ mol−1/RT) cm3 s−1. Transition state theory (TST) calculations based on CBS‐QB3 and G4 levels of theory show good agreement with experimentally obtained rate constants; the experimental values for k1 and k2 are ∼40% lower and ∼50% larger than theoretical predictions, respectively. For the development of a mechanism describing the thermal decomposition of tetramethylsilane (Si(CH3)4; TMS), also TST‐based rate constants for reaction CH3 + Si(CH3)4 → Si(CH3)3CH2 + CH4 (R3) were calculated. A comparison between experimental and theoretical rate constants k2 and k3 with available rate constants from the literature indicates that Si(CH3)4 has very similar reactivity toward H abstractions like neopentane (C(CH3)4), which is the analog hydrocarbon to TMS. Based on these results, the possibility of drawing reactivity analogies between hydrocarbons and structurally similar silicon‐organic compounds for H‐atom abstractions is discussed.
Optimization of a high‐throughput phenotyping method for chain‐forming phytoplankton species
Authors: Gross Susanna , Kourtchenko Olga , Rajala Tuomas , Andersson Björn , Fernandez Luciano , Blomberg Anders , Godhe Anna 
Published: November 2017

AbstractModern equipment facilitates phenotyping of hundreds of strains of unicellular organisms by culturing and monitoring growth in microplates. However, in the field of phytoplankton ecology, automated monitoring of growth is not often done and this method has not been tested for many species. To meet the demand for a high‐throughput technique for monitoring growth of chain‐forming phytoplankton species, we have assessed and optimized a method commonly used for other microorganisms. Skeletonema marinoi is a pelagic chain‐forming diatom, and we have acquired growth patterns in four different treatments (i.e., low and high light, low and high nutrient concentrations) when cultured in multi‐well plates. Due to the unexpected heterogeneity in growth rates and maximum cell densities observed between wells (spatial) and runs (temporal), a set of models was fitted to the obtained phenotypic data to correct for these biases. Models were tested for robustness on two replicate multi‐strain experiments including 23 different strains. Using the model accounting for temporal and spatial bias, we could reliably determine changes in growth rate caused by nutrient treatments as well as differences in cell density as a response to nutrient availability and light treatment. This method can facilitate high‐throughput phenotyping of hundreds of strains, which is often a bottleneck in characterizing the ecology and capacity for adaptation of chain‐forming phytoplankton.