bluuebunny/crossref_metadata_2025_split huggingface dataset:
Frequency and intensity of pyrethroid resistance through the CDC bottle bioassay and their association with the frequency of kdr mutations in Aedes aegypti (Diptera: Culicidae) from Mexico
Authors: Lopez‐Monroy Beatriz , Gutierrez‐Rodriguez Selene M , Villanueva‐Segura Olga Karina , Ponce‐Garcia Gustavo , Morales‐Forcada Franco , Alvarez Leslie C , Flores Adriana E 
Published: March 2018

AbstractBACKGROUNDThe control of Aedes aegypti (L.), the main urban vector that causes arboviral diseases such as dengue, Chikungunya and Zika, has proved to be a challenge because of a rapid increase in insecticide resistance. Therefore, adequate monitoring of insecticide resistance is an essential element in the control of Ae. aegypti and the diseases it transmits. We estimated the frequency and intensity (Resistance Frequency Rapid Diagnostic Test [F‐RDT] and Resistance Intensity Rapid Diagnostic Test [I‐RDT]) of pyrethroid resistance in populations of Ae. aegypti from Mexico using the bottle bioassay and results were related to the frequencies of knockdown resistance (kdr) mutations V1016I and F1534C.RESULTSAll populations under study were resistant to the pyrethroids: bifenthrin (99%), d‐(cis–trans)‐phenothrin (6.3% cis, 91.7% trans) and permethrin (99.5%) according to F‐RDT, and showed moderate to high‐intensity resistance at 10× the diagnostic dose (DD) in I‐RDT. Frequencies of the kdr mutation V1016I in Ae. aegypti populations were correlated with moderate permethrin resistance at 10× DD, whereas F1534C mutation frequencies were correlated with high bifenthrin resistance at 5× DD. Both I1016 and C1535 were highly correlated with high‐intensity phenothrin resistance at 1× to 10× DD.CONCLUSIONSThis study showed that high frequencies of kdr mutations V1016I and F1534C are reflected in the results of F‐RDT and I‐RDT tests. Bioassays in conjunction with the characterization of genetic resistance mechanisms are indispensable in the strategic and rational management of resistance in mosquitoes. © 2018 Society of Chemical Industry
The New Urbanisation Plan and permanent urban settlement of migrants in Chongqing, China
Authors: Zhou Jing 
Published: March 2018

AbstractFor over 30 years, urbanisation in China went along with policies that discouraged migrants from permanently settling in cities. Since 2014, however, policies have shifted towards the encouragement of the urban settlement of migrants. This change has triggered new academic research aimed at re‐understanding the urban integration. Findings of this paper are based on a survey conducted in Chongqing, the first municipality to implement elements of China's New Urbanisation Plan. The focus was on the preference for permanently settling in the city among migrants. Situations before and after the policy transition have been compared, while special attention was given to the impact of 2 key institutional factors—hukou reform and access to public rental housing. The other key to the investigation was whether migrants who have accessed public rental housing seek to buy such housing in order to eventually achieve permanent urban settlement. Results show that the policy transition has had positive effects on the preference of migrants for permanent urban settlement. However, the influence of public rental housing occupancy was quantitatively limited and the impact of the hukou reform has not yet fully crystalized. The policy transition has brought certain equity to disadvantaged and intra‐provincial rural–urban migrants, but this in turn has had negative effects on more advantaged and inter‐provincial migrants. The latter categories appeared to have fewer incentives to approach permanent urban settlement via accessing public rental housing.
CRPS chart: Simultaneously monitoring location and scale under data‐rich environment
Authors: Shi Liangxing , Gong Ling , Lin Dennis K.J. 
Published: March 2018

AbstractThe detection performance of a conventional control chart is usually degraded by a large sample size as in Wang and Tsung. This paper proposes a new control chart under data‐rich environment. The proposed chart is based on the continuous ranked probability score and aims to simultaneously monitor the location and the scale parameters of any continuous process. We simulate different monitoring schemes with various shift patterns to examine the chart performance. Both in‐control and out‐of‐control performances are studied through simulation studies in terms of the mean, the standard deviation, the median, and some percentiles of the average run length distribution. Simulation results show that the proposed chart keeps a high sensitivity to shifts in location and/or scale without any distributional assumptions, and the outperformance improves, as the sample size becomes larger. Examples are given for illustration.
Reliability assessment of complex electromechanical systems: A network perspective
Authors: Lin Shuai , Wang Yanhui , Jia Limin , Zhang Hengrun 
Published: March 2018

AbstractThe network theory is widely applied to improve the reliability of a complex electromechanical system. In this application, system reliability assessment with network theory has been paid a great deal of attention. Because of instrument malfunctions, staff omissions, imperfect inspection strategies, and complex structures, field failure data are often subject to interval censoring, making the holistic reliability assessment becomes a difficult task. Most traditional methods assume reliability of critical components or partial reliability as system reliability, which may cause a large bias in system reliability estimation. This paper proposes a novel method to evaluate and predict the system reliability of a complex electromechanical system subject to the insufficient fault data problem from a network perspective. First, the system modeling based on network theory is developed to describe the topology of a holistic system. Second, interval‐valued intuitionistic hesitant fuzzy number is proposed in order to solve insufficient data for single component. Then, a new measure—comprehensive reliability—that can reflect the reliability of nodes in combination with functional properties and topological properties, which are formulated by failure data and network model, respectively, is constructed for system reliability assessment. Subsequently, an improved system reliability model based on percolation theory is given in terms of comprehensive reliability of nodes. Finally, to verify the effectiveness of the proposed method, a simulation and a real case study for traction system are implemented.
Assessing the impact of requirements review on quality outcomes
Authors: White Timothy E. , Iammartino Ronald , Fossaceca John M. 
Published: March 2018

AbstractStudies demonstrate that differences in how product development organizations and product realization organizations interpret requirements can lead to poor‐quality outcomes. Other research shows that in comparison to communicating requirements inside an organization, communicating requirements in buyer‐supplier relationships can be more difficult and has been identified as a source of rework, poor quality, and increased costs. The Raytheon Company identified misaligned requirements interpretation between the company and its suppliers as a source of program performance inefficiency and therefore instituted a collaborative requirements review process between the company and its critical suppliers. This study examines the impact of these requirements reviews on quality outcomes and demonstrates that these reviews result in positive quality outcomes. In addition, correlation analysis shows a relationship between conducting the requirements reviews and a reduction in failure modes that are characterized by high detection and remediation effort. Considered broadly, our methodology can be applied to other program performance improvement efforts to test their impact on quality outcomes and to reveal related failure modes.
Halogen in materials design: Fluoroammonium lead triiodide (FNH3PbI3) perovskite as a newly discovered dynamical bandgap semiconductor in 3D
Authors: Varadwaj Arpita , Varadwaj Pradeep R. , Yamashita Koichi 
Published: March 2018

AbstractMethylammonium lead triiodide (CH3NH3PbI3) has been recognized as one of the record‐breaking materials for photovoltaics since it can potentially convert light energy into electricity @ 23%. However, it has been suffering from serious stability and environmental issues for which it is not yet put on market. To this end, experimental and theoretical studies are underway to discover versatile halide‐based perovskite compounds. In this article, we report the polymorphic geometries, stabilities, band structures, density of states spectra, and carrier effective asses of a newly identified perovskite semiconductor called fluoroammonium lead triiodide (FNH3PbI3), obtained using compositional engineering combined with periodic density functional theory electronic structure calculations. We show that this compound is stable both in the orthorhombic and pseudocubic phases. We also show that the bandgap for this material oscillates between 1.62 eV (direct) and 1.79 (indirect) for the two polymorphs examined in the pseudocubic phase, with the former and latter values corresponding to the [111] and [110] orientations of the inorganic cationinside the perovskite cage, respectively. Contrariwise, it is direct at Γ‐point for the polymorph examined in the orthorhombic phase. The spin orbit coupling is displayed to have profound effect on the nature and magnitude of the bandgap for this material. This, together with the very small effective masses calculated for the charge carriers comparable with those of CH3NH3PbI3, allows us to propose that FNH3PbI3could be a possible candidate for photovoltaics, as well as for other optoelectronic applications.
Mapping the tandem mass spectrometric characteristics of citrulline‐containing peptides
Authors: Steckel Arnold , Uray Katalin , Turiák Lilla , Gömöry Ágnes , Drahos László , Hudecz Ferenc , Schlosser Gitta 
Published: March 2018

RationaleProtein citrullination (deimination) is a post‐translational modification of proteins converting arginine(s) into citrulline(s). “Overcitrullination” could be associated with severe pathological conditions. Mass spectrometric analysis of modified proteins is hindered by several problems. A comprehensive study of the fragmentation of deiminated peptides is not yet available. In this paper we have made an attempt to describe the characteristics of these processes, based on the studies of epitope model oligopeptides derived from clinically relevant proteins.MethodsSolutions of purified model peptides containing either one or two citrulline residues as well as their native variants were injected directly into the electrospray source of a high accuracy and resolution quadrupole‐time‐of‐flight instrument and were analysed by tandem mass spectrometry using low‐energy collision‐induced dissociation.ResultsLoss of isocyanic acid from citrulline residues is a preferred fragmentation route for deiminated peptides, which yields ornithine residues in the sequence. However, simultaneous detection of both the isocyanic acid loss and sequence fragments is often compromised. A preferential cleavage site was observed between citrulline and any other following amino acids yielding intensive complementary b‐ and y‐type ions. Also, citrulline positioned at the C‐termini displays a preferential cleavage N‐terminal to this residue yielding characteristic y1 ions. These phenomena are described here for the first time and are referred to as the “citrulline effect”.ConclusionsWe found that the citrulline effect is very pronounced and could be used as a complementary tool for the confirmation of modification sites in addition to losses of isocyanic acids from the protonated molecules or from fragment ions. Low collision energy applied to peptide ions having partially mobile protons reveals the site of modification by generating specific and intensive fragments of the sequence. On the other hand, fragmenting precursor ions with mobile protons usually allows full sequence coverage, although citrulline‐specific fragments may exhibit lower intensities compared to other fragments.
Matrix‐assisted laser desorption/ionization imaging mass spectrometry of intraperitoneally injected danegaptide (ZP1609) for treatment of stroke‐reperfusion injury in mice
Authors: Wang Jasmine S.H. , Freitas‐Andrade Moises , Bechberger John F. , Naus Christian C. , Yeung Ken K.‐C. , Whitehead Shawn N. 
Published: March 2018

RationaleThis work focuses on direct matrix‐assisted laser desorption/ionization imaging mass spectrometry (MALDI‐IMS) detection of intraperitoneally (IP)‐injected dipeptide ZP1609 in mouse brain tissue. Direct analysis of drug detection in intact tissue sections provides distribution information that can impact drug development. MALDI‐IMS capabilities of uncovering drug transport across the blood–brain barrier are demonstrated.MethodsSuccessful peptide detection using MALDI‐IMS was achieved using a MALDI TOF/TOF system. Upon optimization of sample preparation procedures for dipeptide ZP1609, an additional tissue acidification procedure was found to greatly enhance signal detection. The imaging data acquired was able to determine successful transport of ZP1609 across the blood–brain barrier. Data obtained from MALDI‐IMS can help shape our understanding of biological functions, disease progression, and effects of drug delivery.ResultsDirect detection of ZP1609 throughout the brain tissue sections was observed from MALDI‐MS images. However, in cases where there was induction of stroke, a peak of lower signal intensity was also detected in the target m/z region. Although distinct differences in signal intensity can be seen between control and experimental groups, fragments and adducts of ZP1609 were investigated using MALDI‐IMS to verify detection of the target analyte.ConclusionsOverall, the data reveals successful penetration of ZP1609 across the blood–brain barrier. The benefits of tissue acidification in the enhancement of detection sensitivity for low‐abundance peptides were demonstrated. MALDI‐IMS has been shown to be a useful technique in the direct detection of drugs within intact brain tissue sections.
On‐line capillary electrophoresis/laser‐induced fluorescence/mass spectrometry analysis of glycans labeled with Teal™ fluorescent dye using an electrokinetic sheath liquid pump‐based nanospray ion source
Authors: Khan Shaheer , Liu Jenkuei , Szabo Zoltan , Kunnummal Baburaj , Han Xiaorui , Ouyang Yilan , Linhardt Robert J. , Xia Qiangwei 
Published: March 2018

RationaleN‐linked glycan analysis of recombinant therapeutic proteins, such as monoclonal antibodies, Fc‐fusion proteins, and antibody‐drug conjugates, provides valuable information regarding protein therapeutics glycosylation profile. Both qualitative identification and quantitative analysis of N‐linked glycans on recombinant therapeutic proteins are critical analytical tasks in the biopharma industry during the development of a biotherapeutic.MethodsCurrently, such analyses are mainly carried out using capillary electrophoresis/laser‐induced fluorescence (CE/LIF), liquid chromatography/fluorescence (LC/FLR), and liquid chromatography/fluorescence/mass spectrometry (LC/FLR/MS) technologies. N‐linked glycans are first released from glycoproteins by enzymatic digestion, then labeled with fluorescence dyes for subsequent CE or LC separation, and LIF or MS detection. Here we present an on‐line CE/LIF/MS N‐glycan analysis workflow that incorporates the fluorescent Teal™ dye and an electrokinetic pump‐based nanospray sheath liquid capillary electrophoresis/mass spectrometry (CE/MS) ion source.ResultsElectrophoresis running buffer systems using ammonium acetate and ammonium hydroxide were developed for the negative ion mode CE/MS analysis of fluorescence‐labeled N‐linked glycans. Results show that on‐line CE/LIF/MS analysis can be readily achieved using this versatile CE/MS ion source on common CE/MS instrument platforms.ConclusionsThis on‐line CE/LIF/MS method using Teal™ fluorescent dye and electrokinetic pump‐based nanospray sheath liquid CE/MS coupling technology holds promise for on‐line quantitation and identification of N‐linked glycans on recombinant therapeutic proteins.
Three‐dimensional Kendrick mass plots as a tool for graphical lipid identification
Authors: Korf Ansgar , Vosse Christian , Schmid Robin , Helmer Patrick O. , Jeck Viola , Hayen Heiko 
Published: March 2018

RationaleThe rising field of lipidomics strongly relies on the identification of lipids in complex matrices. Recent technical advances regarding liquid chromatography (LC) and high‐resolution mass spectrometry (HRMS) enable the mapping of the lipidome of an organism with short data acquisition times. However, interpretation and evaluation of resulting multidimensional datasets are challenging and this is still the bottleneck regarding overall analysis times.MethodsA novel adaption of Kendrick mass plot analysis is presented for a rapid and accurate analysis of lipids in complex matrices. Separation of lipids by their respective head group was achieved via hydrophilic interaction liquid chromatography (HILIC) coupled to HRMS. The resulting LC/HRMS datasets are processed to a list of chromatographically separated features by applying an optimized MZmine 2 workflow. All features are plotted in a three‐dimensional Kendrick mass plot, which allows a fast identification of present lipid classes, based on equidistant features with fitting retention times and the same Kendrick mass defect. Suspected lipid classes are used for exact mass database matching to annotate features. A second three‐dimensional Kendrick mass plot of annotated features of a single lipid class helps to reveal potential database mismatches, resulting in a curated list of identified lipid species.ResultsThe use of the novel adaption of the Kendrick mass plot has accelerated the identification of the relevant lipid species in the green alga Chlamydomonas reinhardtii. A total of 106 species were identified within the lipid classes: phosphatidylserine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, monogalactosyldiacylglycerol, digalactosyldiacylglycerol, and sulfoquinovosyldiacylglycerol.ConclusionsThis work shows how the addition of chromatographic information, i.e. the retention time, to a classical two‐dimensional Kendrick mass plot enables rapid and accurate analysis of LC/HRMS datasets, exemplified on a green alga (C. reinhardtii) sample. Three‐dimensional Kendrick mass plots have improved lipid class identification and fast spotting of falsely annotated lipid species.
Influence of room temperature on magnesium isotope measurements by multi‐collector inductively coupled plasma mass spectrometry
Authors: Zhang Xing‐Chao , Zhang An‐Yu , Zhang Zhao‐Feng , Huang Fang , Yu Hui‐Min 
Published: March 2018

RationaleWe observed that the accuracy and precision of magnesium (Mg) isotope analyses could be affected if the room temperature oscillated during measurements. To achieve high‐quality Mg isotopic data, it is critical to evaluate how the unstable room temperature affects Mg isotope measurements by multi‐collector inductively coupled plasma mass spectrometry (MC‐ICP‐MS).MethodsWe measured the Mg isotopes for the reference material DSM‐3 using MC‐ICP‐MS under oscillating room temperatures in spring. For a comparison, we also measured the Mg isotopes under stable room temperatures, which were achieved by the installation of an improved temperature control system in the laboratory.ResultsThe δ26Mg values measured under oscillating room temperatures have a larger deviation (δ26Mg from −0.09 to 0.08‰, with average δ26Mg = 0.00 ± 0.08‰) than those measured under a stable room temperature (δ26Mg from −0.03 to 0.03‰, with average δ26Mg = 0.00 ± 0.02‰) using the same MC‐ICP‐MS system.ConclusionsThe room temperature variation can influence the stability of MC‐ICP‐MS. Therefore, it is critical to keep the room temperature stable to acquire high‐precision and accurate isotopic data when using MC‐ICP‐MS, especially when using the sample‐standard bracketing (SSB) correction method.
Rapid oligonucleotide drug impurity determination by direct spectral comparison of ion‐pair reversed‐phase high‐performance liquid chromatography electrospray ionization mass spectrometry data
Authors: Roussis Stilianos G. , Koch Charlie , Capaldi Daniel , Rentel Claus 
Published: March 2018

RationaleQuantitative ion‐pair (IP) high‐performance liquid chromatography/mass spectrometry (HPLC/MS) methods are employed to determine the complex impurity profiles of oligonucleotide therapeutics. While impurities that co‐elute with the main product are routinely monitored, the large number of early and late eluting impurities makes their individual measurements tedious and time‐consuming. An improved method is needed for routine analyses.MethodsA Combined Ranking (CR) index is developed to provide a composite value for both qualitative and quantitative impurity changes. Positive and Negative Impurity Change (PIC/NIC) indices are developed to determine the degree and direction of change. Optimized experimental conditions are determined for the characterization of trace levels of impurities. Replicate analysis, blank subtraction, and signal processing approaches are used to enhance the signal‐to noise (S/N). Dot‐product and Euclidean distance equations monitor spectral changes.ResultsSpiking experiments with individual and complex impurity mixtures show the method can distinguish among samples differing in impurity content by 0.2% wt. The method has been applied to monitor changes in impurity profiles among different batches of the same oligonucleotide and changes in the same batch over time (stability analysis). The method permits rapid determination of changes in the types and amounts (increases and decreases) of impurities present.ConclusionsA novel approach for the rapid determination of changes in the impurity profile of oligonucleotide therapeutics has been developed. The straightforward data treatment and the speed and simplicity of the approach make the method easy to implement and use. Possible quality control applications include drug substance and drug product stability studies, and the assessment of batch‐to‐batch variability.