bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aqueous ethyl acetate as a novel solvent for the degreasing of black soldier fly (Hermetia illucens L.) larvae: degreasing rate, nutritional value evaluation of the degreased meal, and thermal properties
Authors: Wang Tielin , Shen Qiao , Feng Weiliang , Wang Cunwen , Yang Fang 
Published: November 2019

AbstractBACKGROUNDThe aim of this study was to select appropriate low‐toxicity degreasing solvents to degrease black soldier fly (BSF, Hermetia illucens L.) larvae to prepare high‐quality protein. Aqueous ethyl acetate was chosen as the solvent to extract BSF protein, and traditional solvents, such as petroleum ether, n‐hexane, and isopropanol, were chosen as controls.RESULTSThe meal degreased by aqueous ethyl acetate (the volume ratio of ethyl acetate to water is 90 to 10, EA + W10) shows a high degreasing rate (29.04%), crude protein content (562.3 g kg−1), essential amino acid index (EAAI, 95.57), and digestible indispensable amino acid score (DIAAS, 85). The digestibility of the degreased meal samples in the simulated in vitro intestine can reach 76.52%. Thermodynamic analysis and the apparent morphology of the protein fragments showed that the meal degreased by EA + W10 exhibited thermodynamic stability, which suggests that using aqueous ethyl acetate as the degreasing solvent did not affect the nutritional value of the degreased meal.CONCLUSIONThe results suggest that aqueous ethyl acetate (EA + W10) can be used as a novel solvent in the degreasing of BSF larvae meal to prepare high‐quality protein with high EAAI and DIAAS and good digestibility. © 2019 Society of Chemical Industry
Separation and quantification of imidazoles in atmospheric particles using LC–Orbitrap‐MS
Authors: Teich Monique , Schmidtpott Mechthild , van Pinxteren Dominik , Chen Jianmin , Herrmann Hartmut 
Published: November 2019

AbstractA method using ultra‐high performance liquid chromatography coupled to a high resolution Orbitrap mass spectrometer was developed to identify and quantify imidazoles in aqueous extracts of aerosol particles. The aqueous particle extract was used without further enrichment or sample clean‐up. Five columns were tested for efficient separation of ten imidazoles and the Acquity HSS T3 column was chosen for further optimization. Low limits of detection (<25 nM) and good intraday and interday repeatability (<1.6 and <6%, respectively) were achieved. Investigation of matrix effects showed that external calibration is applicable when the loading of organic carbon in the sample is below 10 µg m−3. The developed method was applied to ten real samples, and six out of the ten test imidazoles were successfully quantified, while six further imidazoles were qualitatively identified, among them 4‐imidazolecarboxaldehyde and 4‐methyl‐5‐imidazolecarboxaldehyde. Advantages of the method are the minimal sample preparation, the short run time for each sample, and the low detection limits. These allow for a fast and reliable quantification of imidazoles even in a large number of aqueous particle extract samples.
Genetic Management of Captive and Reintroduced Bilby Populations
Authors: Lott Matthew J. , Wright Belinda R. , Kemp Leah F. , Johnson Rebecca N. , Hogg Carolyn J. 
Published: November 2019

ABSTRACTCaptive breeding and translocation, whereby selected individuals are used to supplement or re‐establish failing populations, are powerful tools for conserving threatened fauna. These tools, however, are rarely successful at establishing self‐sustaining populations that can survive without ongoing human assistance. The maintenance of genetic diversity and demographic security in captivity, or following wildlife translocation events, is important for improving the long‐term effectiveness of threatened species recovery efforts around the world. Routine population monitoring using hypervariable genetic markers represents a promising technique for evaluating the effect of established management practices on population structure and genetic diversity across various spatial and temporal scales. In this study, we employed a data set of 1,068 single nucleotide polymorphisms to conduct a comprehensive survey of population structure and genetic diversity in greater bilbies (Macrotis lagotis) held at 13 zoos and wildlife sanctuaries across Australia between August 1996 and December 2016. We observed significant genetic structuring across the study sites, consistent with the limited exchange of animals between independently managed facilities. The majority of variation, however, still occurred at the level of individual bilbies (75%, P < 0.001). We also uncovered evidence for an ongoing loss of genetic diversity in some conservation‐fenced populations, despite a slight excess of heterozygosity across the sampling sites as a whole. Maintaining the genetic health of bilbies in captivity or following translocation will therefore require stakeholders to focus on reducing individual mortality, and maintaining genetic connectivity across all existing populations through the regular exchange of selected individuals. As such, admixture is expected to play an increasingly important role in future conservation programs. © 2019 The Authors. Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.
Stepwise Lateral Extension of Phenyl‐Substituted Linear Polyphenylenes
Authors: Hou Ian Cheng‐Yi , Narita Akimitsu , Müllen Klaus 
Published: November 2019

AbstractPolyphenylenes (PPs) are unique polymers showing high mechanical strength and chemical stability, and having potential applications, for example, in proton transfer and gas‐separation membranes. Moreover, phenyl‐substituted linear PPs can serve as precursors for bottom‐up syntheses of graphene nanoribbons (GNRs), a new class of nanoscale carbon materials that appear promising for nanoelectronics. Notably, lateral extensions of linear PPs with appropriate “branched” phenyl substituents, that is, avoiding spatial overlap of benzene rings in their projections into a plane, can lead to wider GNRs with modulated electronic and optical properties. GNRs with widths up to ≈2 nm are obtained, but synthetic methods to further expand PPs laterally so as to achieve even wider GNRs have not yet been developed. Here, phenyl‐substituted linear PPs bearing two ethynyl groups at “outer” positions in each repeating unit, together with 3,4‐diphenylcyclopentadienones bearing a trimethylsilyl‐protected ethynyl group are used for stepwise lateral extension of the PPs, based on a sequence of Diels–Alder cycloadditions and deprotections. Each successive reaction step is corroborated by 1H NMR and IR spectroscopy, as well as gel permeation chromatography, providing a new pathway toward branched polyphenylenes with linear‐PP‐backbones that can potentially serve as precursors of wider GNRs with tunable electronic bandgaps.
On convex multiobjective programs with application to portfolio optimization
Authors: Jayasekara Pubudu L.W. , Adelgren Nathan , Wiecek Margaret M. 
Published: November 2019

AbstractFocusing on (strictly) convex multiobjective programs (MOPs), we review some well‐established scalarizations in multiobjective programming from the perspective of parametric optimization and propose a modified hybrid scalarization suitable for a class of specially structured convex MOPs. Because multiobjective quadratic programs are a prominent class of convex MOPs due to their broad applicability, we review the state‐of‐the‐art algorithms for computing their efficient solutions. These two lines of investigation are merged to solve multiobjective portfolio optimization problems with three or more quadratic objective functions, a class of problems that has not been solved before. Computational examples are provided.
Coupling of NMR to ACOMP for Terpolymerization Monitoring and Control
Authors: McAfee Terry , Jarand Curtis W. , Zekoski Thomas , Montgomery Rick , Reed Wayne F. 
Published: November 2019

AbstractMonitoring and control of free radical copolymerization using automatic continuous online monitoring of polymerization reactions (ACOMP) with UV detection has been recently achieved. It is difficult, however, to achieve spectral separation of similar monomers with UV alone. Here, nuclear magnetic resonance (NMR) is coupled to ACOMP for the first time and terpolymerization reactions involving acrylamide (Am), sodium acrylate (Ac), and styrene sulfonate (SS) are monitored, and a first attempt at active composition control is made. The NMR resolves the concentrations of Am and Ac, while the UV resolves SS and the sum of Am and Ac. NMR analysis is performed in water, using signal suppression, to eliminate the need for deuterated solvents. From this, instantaneous fractions of each comonomer in the terpolymer are continuously known, along with weight average molecular weight and intrinsic viscosity, IV. Am and Ac have similar reactivities, whereas the reactivity ratio of SS is much larger. Hence, there is high composition drift in batch polymerization and SS is rapidly consumed, leaving a final copolymer of Am and SS to form. Maintaining constant terpolymer composition is taken as a first step toward active control.
Wall‐slab joint parameter identification of a reinforced concrete structure using possibly corrupted modal data
Authors: Oliveira Hugo , Louf François , Hervé‐Secourgeon Estelle , Gatuingt Fabrice 
Published: November 2019

SummaryIn numerical models, the connections among component members are crucial for the prediction of structural behaviour under different types of solicitations. In reinforced structures, the connections are often assumed rigid, what may not be realistic in many practical cases. As alternative, a semi‐rigid behaviour depending on a set of independent parameters can be proposed. In this case, a new difficulty arises, which is finding the appropriate values for those parameters. The present study proposes a numerical strategy for identification of the connection parameters based on the constitutive relation error (CRE). To include all available information, an augmented version (Modified CRE) is implemented. The parameters search is iterative and require large amount of system response analysis. To increase the computational efficiency, a reduced order model is adopted. The proposed approach shows low‐sensitivity to limited lack of information and also to support condition variability, both of them verified numerically. In this work, experimental tests for a real 1:4 scale structure is utilized for finding the parameters corresponding to the first three modal shapes. A good agreement between numerical predictions and observations is verified, what highlights the accuracy and stability of the proposed numerical approach. The present study may also find applications in the domain of design of experiments.
Noninvasive prenatal screening for patients with high body mass index: Evaluating the impact of a customized whole genome sequencing workflow on sensitivity and residual risk
Authors: Muzzey Dale , Goldberg James D. , Haverty Carrie 
Published: November 2019

AbstractObjectiveWomen with high body mass index (BMI) tend to have reduced fetal fraction (FF) during cell‐free DNA‐based noninvasive prenatal screening (NIPS), causing test failure rates up to 24.3% and prompting guidelines that recommend aneuploidy screening other than NIPS for patients with significant obesity. Because alternatives to NIPS are only preferable if they perform better, we compared the respective sensitivities at different BMI levels of traditional aneuploidy screening and a customized whole‐genome sequencing NIPS.MethodThe relationship between FF, aneuploidy, and BMI was quantified from 58 105 patients screened with a customized NIPS that does not fail samples because of low FF alone. Expected analytical sensitivity as a function of aneuploidy and BMI (eg, trisomy 18 sensitivity when BMI = 35) was determined by scaling the BMI‐ and aneuploidy‐specific FF distribution by the FF‐ and aneuploidy‐specific sensitivity calculated from empirically informed simulations.ResultsAcross all classes of obesity and assuming zero FF‐related test failures, analytical sensitivity for the investigated NIPS exceeded that of traditional aneuploidy screening for trisomies 13, 18, and 21.ConclusionRelative to traditional aneuploidy screening, a customized NIPS with high accuracy at low FF and a low test‐failure rate is a superior screening option for women with high BMI.
Quantitative Proteomics Reveals Remodeling of Protein Repertoire Across Life Phases of Daphnia pulex
Authors: Peshkin Leonid , Boukhali Myriam , Haas Wilhelm , Kirschner Marc W. , Yampolsky Lev Y. 
Published: November 2019

AbstractAlthough the microcrustacean Daphnia is becoming an organism of choice for proteomic studies, protein expression across its life cycle have not been fully characterized. Proteomes of adult females, juveniles, asexually produced embryos, and the ephippia‐resting stages containing sexually produced diapausing freezing‐ and desiccation‐resistant embryos are analyzed. Overall, proteins with known molecular functions are more likely to be detected than proteins with no detectable orthology. Similarly, proteins with stronger gene model support in two independent genome assemblies can be detected, than those without such support. This suggests that the proteomics pipeline can be applied to verify hypothesized proteins, even given questionable reference gene models. In particular, upregulation of vitellogenins and downregulation of actins and myosins in embryos of both types, relative to juveniles and adults, and overrepresentation of cell‐cycle related proteins in the developing embryos, relative to diapausing embryos and adults, are observed. Upregulation of small heat‐shock proteins and peroxidases, as well as overrepresentation of stress‐response proteins in the ephippium relative to the asexually produced non‐diapausing embryos, is found. The ephippium also shows upregulation of three trehalose‐synthesis proteins and downregulation of a trehalose hydrolase, consistent with the role of trehalose in protection against freezing and desiccation.
Template‐based modeling of diverse protein interactions in CAPRI rounds 38‐45
Authors: Dapkūnas Justas , Kairys Visvaldas , Olechnovič Kliment , Venclovas Česlovas 
Published: November 2019

AbstractStructures of proteins complexed with other proteins, peptides, or ligands are essential for investigation of molecular mechanisms. However, the experimental structures of protein complexes of interest are often not available. Therefore, computational methods are widely used to predict these structures, and, of those methods, template‐based modeling is the most successful. In the rounds 38‐45 of the Critical Assessment of PRediction of Interactions (CAPRI), we applied template‐based modeling for 9 of 11 protein‐protein and protein‐peptide interaction targets, resulting in medium and high‐quality models for six targets. For the protein‐oligosaccharide docking targets, we used constraints derived from template structures, and generated models of at least acceptable quality for most of the targets. Apparently, high flexibility of oligosaccharide molecules was the main cause preventing us from obtaining models of higher quality. We also participated in the CAPRI scoring challenge, the goal of which was to identify the highest quality models from a large pool of decoys. In this experiment, we tested VoroMQA, a scoring method based on interatomic contact areas. The results showed VoroMQA to be quite effective in scoring strongly binding and obligatory protein complexes, but less successful in the case of transient interactions. We extensively used manual intervention in both CAPRI modeling and scoring experiments. This oftentimes allowed us to select the correct templates from available alternatives and to limit the search space during the model scoring.
On the structure and function of Escherichia coli YjhC: An oxidoreductase involved in bacterial sialic acid metabolism
Authors: Horne Christopher R. , Kind Laura , Davies James S. , Dobson Renwick C. J. 
Published: November 2019

AbstractHuman pathogenic and commensal bacteria have evolved the ability to scavenge host‐derived sialic acids and subsequently degrade them as a source of nutrition. Expression of the Escherichia coli yjhBC operon is controlled by the repressor protein nanR, which regulates the core machinery responsible for the import and catabolic processing of sialic acid. The role of the yjhBC encoded proteins is not known—here, we demonstrate that the enzyme YjhC is an oxidoreductase/dehydrogenase involved in bacterial sialic acid degradation. First, we demonstrate in vivo using knockout experiments that YjhC is broadly involved in carbohydrate metabolism, including that of N‐acetyl‐d‐glucosamine, N‐acetyl‐d‐galactosamine and N‐acetylneuraminic acid. Differential scanning fluorimetry demonstrates that YjhC binds N‐acetylneuraminic acid and its lactone variant, along with NAD(H), which is consistent with its role as an oxidoreductase. Next, we solved the crystal structure of YjhC in complex with the NAD(H) cofactor to 1.35 Å resolution. The protein fold belongs to the Gfo/Idh/MocA protein family. The dimeric assembly observed in the crystal form is confirmed through solution studies. Ensemble refinement reveals a flexible loop region that may play a key role during catalysis, providing essential contacts to stabilize the substrate—a unique feature to YjhC among closely related structures. Guided by the structure, in silico docking experiments support the binding of sialic acid and several common derivatives in the binding pocket, which has an overall positive charge distribution. Taken together, our results verify the role of YjhC as a bona fide oxidoreductase/dehydrogenase and provide the first evidence to support its involvement in sialic acid metabolism.
Facile Construction of Microgel based Biomimetic Glutathione Peroxidase with Temperature Responsive Catalytic Activity
Authors: Jiao Shufei , Liang Xingtang , Zhang Ruirui , Zhong Shuming , Zheng Yunying , Wang Shuangshuang , Liu Min , Hu Xiaoxi , Yin Yanzhen 
Published: November 2019

AbstractGlutathione peroxidase (GPx) is an important antioxidant enzyme. The exploration of a simple and efficient strategy for preparing biomimetic GPx is of great significance, because it can provide theoretical supports for the development of antioxidant drugs that can regulate the concentration of free radicals. In this work, a microgel based biomimetic GPx (PAMTegel) with temperature responsive catalytic activity was simply and efficiently constructed by the combination of one‐pot method and ATRP polymerization. The PAMTegel exhibited a typical enzymatic catalytic behavior with temperature responsiveness. The catalytic activity of PAMTegel could be facilely regulated by adjusting temperature from 25 to 50 °C. The hydrophobicity change of poly(N‐isopropylacrylamide) (PNIPAM) molecular chain in the PAMTegel was the key factor to manage the catalytic activity. The strategy for constructing temperature responsive biomimetic GPx and the related investigation for its catalytic mechanism may provide an important theoretical basis for the development of intelligent antioxidants.
A contingency perspective on imitation strategies: When is “benchmarking” ineffective?
Authors: Posen Hart E. , Yi Sangyoon , Lee Jeho 
Published: November 2019

AbstractResearch SummaryImitation is ubiquitous, yet the comparative efficacy of imitation strategies is poorly understood. A popular imitation strategy, sometimes called benchmarking, “mixes‐and‐matches” practices common to leading firms. Using computational models, we compare benchmarking with the “copy‐the‐best” imitation strategy of copying a subset of the best‐performing firm's practices. We find that benchmarking is more effective in heterogeneous environments, where practices that are good for firms in one group (e.g., geographic submarket) may be bad for firms in another. Firms using mix‐and‐match tend to imitate practices of rivals within their group, less likely copying inappropriate practices from other groups. In homogeneous environments, however, the “copy‐the‐best” strategy is superior because firms are more likely to go beyond their group and copy novel good practices from rivals in other groups.Managerial SummaryMix‐and‐match imitation, popularly known as benchmarking, is believed to be an effective means of enhancing firm performance. The popular press is replete with how‐to books for managers. However, our results suggest that this belief may be wrong under some industry conditions, in particular, where practices that are good for firms in one group (e.g., geographic submarket) are also good for firms in another. The efficacy of benchmarking is likely to be undermined by fads, fashions, and bandwagons that overemphasize practices common to leading firms. Our study highlights the possibility that, under these conditions, imitating common practices is prone to propagate bad practices and widespread practices may not always be good practices.
The origins of firm strategy: Learning by economic experimentation and strategic pivots in the early automobile industry
Authors: Pillai Sandeep D. , Goldfarb Brent , Kirsch David A. 
Published: November 2019

AbstractResearch SummaryWe explore the effectiveness of economic experimentation as a learning mechanism through a historical exploration of the early automobile industry. We focus on a particular subset of economic experiments, called strategic pivots, that requires irreversible firm commitments. Our quantitative analysis suggests that strategic pivoting was associated with success. We then use historical methods to understand whether this association is reasonably interpreted as a causal link. We identify lessons that could only plausibly have been learned through strategic pivoting and document that those firms that were able to learn from the strategic pivots were most likely to succeed. We discuss the generalizability of our findings to build the hypothesis that strategic pivots and economic experiments originate firm strategy.Managerial SummaryWe explore the effectiveness of experimentation as a learning mechanism through a historical exploration of the early automobile industry. We focus on a particular subset of experiments, called strategic pivots, that requires irreversible firm commitments. Our analysis suggests that strategic pivoting was associated with success. We identify lessons that could only plausibly be learned through strategic pivoting and document that those firms that were able to learn from the strategic pivots were most likely to succeed. Even though firms may use lean techniques, market solutions may only be discovered through strategic pivots whose outcomes are unknowable ex‐ante. Therefore, successful strategies reflect an element of luck.