bluuebunny/crossref_metadata_2025 huggingface dataset:
An investigation of the bluish material on Ceres
Authors: Stephan K. , Jaumann R. , Krohn K. , Schmedemann N. , Zambon F. , Tosi F. , Carrozzo F. G. , McFadden L. A. , Otto K. , De Sanctis M. C. , Ammannito E. , Matz K.‐D. , Roatsch T. , Preusker F. , Raymond C. A. , Russell C. T.
Published: February 2017

The dwarf planet Ceres shows spatially well‐defined regions, which exhibit a negative (blue) spectral slope between 0.5 and 2.5 µm. Comparisons with planetary bodies known to exhibit a blue slope and spectral properties of materials identified on Ceres's surface based on infrared wavelength signatures indicate that the spectral changes could be related to physical properties of the surface material rather than variations in its composition. The close association of bluish surface regions to fresh impact craters implies a possible relationship to an impact‐triggered alteration and/or space weathering processes. The bluish regions could be linked with blankets of ultrafine grains and partly amorphous phyllosilicates, which form larger agglomerates due to the sticky behavior of impact‐induced phyllosilicate dust and/or the amorphization of the ejecta material during the impact process. Space weathering processes (micrometeoritic impacts, temperature changes) cause a reversal of the agglutination process and a recrystallization of the surface material with time resulting in a reddening of the spectral slope.
A climate model projection weighting scheme accounting for performance and interdependence
Authors: Knutti Reto , Sedláček Jan , Sanderson Benjamin M. , Lorenz Ruth , Fischer Erich M. , Eyring Veronika
Published: February 2017

Uncertainties of climate projections are routinely assessed by considering simulations from different models. Observations are used to evaluate models, yet there is a debate about whether and how to explicitly weight model projections by agreement with observations. Here we present a straightforward weighting scheme that accounts both for the large differences in model performance and for model interdependencies, and we test reliability in a perfect model setup. We provide weighted multimodel projections of Arctic sea ice and temperature as a case study to demonstrate that, for some questions at least, it is meaningless to treat all models equally. The constrained ensemble shows reduced spread and a more rapid sea ice decline than the unweighted ensemble. We argue that the growing number of models with different characteristics and considerable interdependence finally justifies abandoning strict model democracy, and we provide guidance on when and how this can be achieved robustly.
Meltwater pulse recorded in Last Interglacial mollusk shells from Bermuda
Authors: Winkelstern Ian Z. , Rowe Mark P. , Lohmann Kyger C. , Defliese William F. , Petersen Sierra V. , Brewer Aaron W.
Published: February 2017

The warm climate of Bermuda today is modulated by the nearby presence of the Gulf Stream current. However, iceberg scours in the Florida Strait and the presence of ice‐rafted debris in Bermuda Rise sediments indicate that, during the last deglaciation, icebergs discharged from the Laurentide Ice Sheet traveled as far south as subtropical latitudes. We present evidence that an event of similar magnitude affected the subtropics during the Last Interglacial, potentially due to melting of the Greenland Ice Sheet. Using the clumped isotope paleothermometer, we found temperatures ~10°C colder and seawater δ18O values ~2‰ lower than modern in Last Interglacial Cittarium pica shells from Grape Bay, Bermuda. In contrast, Last Interglacial shells from Rocky Bay, Bermuda, record temperatures only slightly colder and seawater δ18O values similar to modern, likely representing more typical Last Interglacial conditions in Bermuda outside of a meltwater event. The significantly colder ocean temperatures observed in Grape Bay samples illustrate the extreme sensitivity of Bermudian climate to broad‐scale ocean circulation changes. They indicate routine meltwater transport in the North Atlantic to near‐equatorial latitudes, which would likely have resulted in disruption of the Atlantic Meridional Overturning Circulation. These data demonstrate that future melting of the Greenland Ice Sheet, a potential source of the Last Interglacial meltwater event, could have dramatic climate effects outside of the high latitudes.
Strength and Ductility Balance on an Extruded Mg–Zn–Ca–La Alloy
Authors: Du Yuzhou , Zheng Mingyi , Qiao Xiaoguang , Chen Hongjun , Jiang Bailing
Published: February 2017

Mg–6Zn–0.7Ca–0.2La (wt%) alloy is cast and extruded in the present study. The microstructure of the as‐extruded Mg–6Zn–0.7Ca–0.2La (wt%) alloy is investigated via scanning electron microscopy (SEM), transmission electron microscope (TEM) and electron backscattering diffraction (EBSD). Results show that the as‐extruded Mg–6Zn–0.7Ca–0.2La (wt%) alloy exhibited a balanced strength and ductility with the yield strength of 261 MPa and elongation‐to‐fracture of 20.7%. The superior strength is mainly attributed to grain refinement and precipitates, whereas the plasticity is ascribed to fine homogenous microstructure and weaker texture. The fine microstructure is obtained in the as‐extruded Mg–6Zn–0.7Ca–0.2La (wt%) alloy, mainly attributing to the dynamic recrystallization and pinning effects from precipitates.
Biofluid‐Triggered Burst Release from an Adaptive Covalently Assembled Dipeptide Nanocontainer for Emergency Treatment
Authors: Fei Jinbo , Zhang He , Wang Anhe , Qin Chenchen , Xue Huimin , Li Junbai
Published: February 2017

The construction of quickly dissociating containers holding bioactive components that meet the extreme requirements of emergency treatment is highly desirable but remains a great challenge. Here the use of small‐molecule‐induced dynamic covalent assembly is reported for simple and tunable fabrication of a biocompatible diphenylalanine‐based nanocontainer toward rapidly responsive cargo delivery. The assembled nanocontainer can adaptively encapsulate various charged or neutral molecules. Upon biofluid trigger, the encapsulated molecules and bioactive proteins are released in a burst (within 5 s) from the nanocontainer due to highly sensitive deprotonation‐mediated disruption of hydrogen bonding. This highlighted feature allows the nanocontainer as an excellent “fast dissolving” delivery vehicle available in spray dosage form for medical emergencies, as demonstrated by in vivo application for massive hemorrhage.
Efficient Selenium‐Catalyzed Selective C(sp3)−H Oxidation of Benzylpyridines with Molecular Oxygen
Authors: Jin Weiwei , Zheng Poonnapa , Wong Wing‐Tak , Law Ga‐Lai
Published: February 2017

An efficient selenium‐catalyzed direct oxidation of benzylpyridines in aqueous DMSO has been successfully developed by using molecular oxygen as the oxidant. A variety of benzoylpyridines with broad functional group tolerance were obtained in modest to excellent yields and with exclusive chemoselectivity.

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Poly(p‐vinylbenzoic acid)‐block‐polystyrene Self‐assembled Structures as Templates in the Synthesis of ZIF‐8
Authors: Yang Yongfang , Li Hua , Zhang Yue , Wang Hefang , Xu Lidong , Zhao Hanying
Published: February 2017

Hybrid nanocrystals of PVBA‐b‐PS/ZIF‐8 were prepared by the growth of ZIF‐8 on the surface of the self‐assembled structures from poly(p‐vinylbenzoic acid)‐block‐polystyrene. Two different morphologies—micelles and vesicles—were obtained in selective solvents owing to the different ratios of PVBA to PS blocks. The structure and morphology of the PVBA‐b‐PS/ZIF‐8 composites were characterized by Fourier transform IR spectroscopy, thermogravimetric analysis, X‐ray diffraction, transmission electron microscopy and scanning electron microscopy. PVBA‐b‐PS/ZIF‐8 showed high catalytic performance in Knoevenagel condensation reactions at room temperature, which were attributed to the more exposed active sites of the small ZIF‐8 nanocrystals grown in a confined space and a high concentration of reactants in the polymeric aggregates.
Coordination‐Driven Dimerization of Zinc Chlorophyll Derivatives Possessing a Dialkylamino Group
Authors: Watanabe Hiroaki , Kamatani Yusuke , Tamiaki Hitoshi
Published: February 2017

Zinc chlorophyll derivatives Zn‐1–3 possessing a tertiary amino group at the C31 position have been synthesized through reductive amination of methyl pyropheophorbide‐d obtained from naturally occurring chlorophyll‐a. In a dilute CH2Cl2 solution as well as in a dilute 10 %(v/v) CH2Cl2/hexane solution, Zn‐1 possessing a dimethylamino group at the C31 position showed red‐shifted UV/Vis absorption and intensified exciton‐coupling circular dichroism (CD) spectra at room temperature owing to its dimer formation via coordination to the central zinc by the 31‐N atom of the dimethylamino group. However, Zn‐2/3 bearing 31‐ethylmethylamino/diethylamino groups did not. The difference was dependent on the steric factor of the substituents in the tertiary amino group, where an increase of the carbon numbers on the N atom reduced the intermolecular N⋅⋅⋅Zn coordination. UV/Vis, CD, and 1H NMR spectroscopic analyses including DOSY measurements revealed that Zn‐1 formed closed‐type dimers via an opened dimer by single‐to‐double axial coordination with an increase in concentration and a temperature decrease in CH2Cl2, while Zn‐2/3 gave open and flexible dimers in a concentrated CH2Cl2 solution at low temperature. The supramolecular closed dimer structures of Zn‐1 were estimated by molecular modelling calculations, which showed these structures were promising models for the chlorophyll dimer in a photosynthetic reaction center.
Optimal Modified Tracking Performance of Time‐Delay Systems with Packet Dropouts Constraint
Authors: Zhan Xi‐Sheng , Zhou Zhu‐Jun , Wu Jie , Han Tao
Published: February 2017

This paper investigates the optimal modified tracking performance of networked time‐delay systems with packet dropout constraint. A novel modified tracking performance index of networked time‐delay systems is proposed which prevents variations in the tracking error from leading to invalid data when there is no integrator in the plant. Some explicit expressions are obtained by using spectral decomposition. The obtained results show that the optimal modified tracking performance is related to the intrinsic properties of a given plant such as non‐minimum phase (NMP) zeros, unstable poles and time‐delay. Furthermore, the modified factor and packet dropout probability affect the optimal modified tracking performance of the networked time‐delay systems. The optimal modified tracking performance with the channel input power constraint is obtained by searching through all stabilizing one‐parameter compensators. Finally, the efficiency of the result is verified using some typical examples.
Manufacturing of recombinant adeno‐associated viruses using mammalian expression platforms
Authors: Robert Marc‐André , Chahal Parminder S. , Audy Alexandre , Kamen Amine , Gilbert Rénald , Gaillet Bruno
Published: February 2017

Manufacturing practices for recombinant adeno‐associated viruses (AAV) have improved in the last decade through the development of new platforms in conjunction with better production and purification methods. In this review, we discuss the advantages and limitations of the most popular systems and methods employed with mammalian cell platforms. Methods and systems such as transient transfection, packaging and producer cells and adenovirus and herpes simplex virus are described. In terms of best production yields, they are comparable with about 104–105 vector genomes produced per cell but transient transfection of HEK293 cells is by far the most commonly used. For small‐scale productions, AAV can be directly purified from the producing cell lysate by ultracentrifugation on a CsCl or iodixanol‐step gradient whereas large‐scale purification requires a combination of multiple steps. Micro/macrofiltration (i.e. including tangential flow filtration and/or dead‐end filtration) and chromatography based‐methods are used for large‐scale purification. Purified AAV products must then be quantified and characterized to ensure quality. Recent purification methods and current analytical techniques are reviewed here. Finally, AAV technology is very promising, but manufacturing improvements are still required to meet the needs of affordable, safe and effective AAV vectors essential for licensing of gene therapy clinical protocols.
Enantioselective Reduction of Citral Isomers in NCR Ene Reductase: Analysis of an Active‐Site Mutant Library
Authors: Kress Nico , Rapp Johanna , Hauer Bernhard
Published: February 2017

A deeper understanding of the >99 % S‐selective reduction of both isomers of citral catalyzed by NCR ene reductase was achieved by active‐site mutational studies and docking simulation. Though structurally similar, the E/Z isomers of citral showed a significantly varying selectivity response to introduced mutations. Although it was possible to invert (E)‐citral reduction enantioselectivity to ee 46 % (R) by introducing mutation W66A, for (Z)‐citral it remained ≥88 % (S) for all single‐residue variants. Residue 66 seems to act as a lever for opposite binding modes. This was underlined by a W66A‐based double‐mutant library that enhanced the (E)‐citral derived enantioselectivity to 63 % (R) and significantly lowered the S selectivity for (Z)‐citral to 44 % (S). Formation of (R)‐citronellal from an (E/Z)‐citral mixture is a desire in industrial (−)‐menthol synthesis. Our findings pave the way for a rational enzyme engineering solution.
Dominant deafness–onychodystrophy syndrome caused by an ATP6V1B2 mutation
Authors: Menendez Ibis , Carranza Claudia , Herrera Mariana , Marroquin Nely , Foster Joseph , Cengiz Filiz Basak , Bademci Guney , Tekin Mustafa
Published: February 2017

Key Clinical Message

Our report clarifies the role of ATP6V1B2 in patients with deafness and onycho‐osteodystrophy and confirms that a recurring ATP6V1B2 c.1516C>T [p.(Arg506*)], variant causes dominant deafness–onychodystrophy (DDOD) syndrome.
The different features of angiographic peri‐stent contrast staining after implantation of sirolimus‐eluting stents
Authors: Kageyama Michiya , Abe Shichiro , Koichi Iwamatsu , Nishida Hiroaki , Kiozumi Satoshi , Nasuno Takahisa , Yoneda Shuichi , Sakuma Masashi , Inoue Teruo
Published: February 2017

Key Clinical Message

If we had a case with angiographic peri‐stent contrast staining(PSS)s after the first‐generation sirolimus‐eluting stent, we need a further observation using coronary imaging modalities to evaluate the risk of very late stent thrombosis due to PSSs and to continue or to resume the dual antiplatelet therapy if necessary.
Nickel‐Foam‐Supported Co3O4 Nanosheets/PPy Nanowire Heterostructure for Non‐enzymatic Glucose Sensing
Authors: Dai Hongxiu , Lin Meng , Wang Nan , Xu Fei , Wang Donglei , Ma Houyi
Published: February 2017

Cobalt oxide nanosheets (Co3O4 NSs)/polypyrrole nanowire (PPy NW) core‐shell nano‐heterostructures based on nickel foam (NF) were fabricated for electrochemical non‐enzymatic glucose determination. The Co3O4/PPy nanostructures grew directly on nickel foam substrate by electrochemical deposition processes. The PPy NW core and the Co3O4 NS shell constructed the hierarchical nanocomposites to form a three dimensional micro−nanostructure in the micropores of NF. The as‐prepared Co3O4/PPy/NF heterostructures were characterized by using scanning electron microscopy, transmission electron microscopy, and X‐ray photoelectron spectroscopy. The introduction of the Co3O4 NSs can provide a high surface area and lead to high sensitivity to glucose. Chronoamperometry was used to evaluate the sensitivity of the sensor toward glucose. Compared with NF, PPy/NF, and Co(OH)2/PPy/NF electrodes, the Co3O4/PPy/NF electrode exhibited higher electrocatalytic activity for the oxidation of glucose, and the proposed glucose sensor showed linear electrochemical responses to glucose with a low detection limit of 0.74 μM (S/N=3). In addition, the prepared biosensor revealed good selectivity in the presence of electro‐active species such as d‐fructose, uric acid, ascorbic acid and hydrogen peroxide, and provided an excellent platform for the determination of glucose in human urine samples.
Quantitative Structure–Activity Relationships for the Nucleophilicity of Trivalent Boron Compounds
Authors: García‐López Diego , Cid Jessica , Marqués Ruben , Fernández Elena , Carbó Jorge J.
Published: February 2017

We describe herein the development of quantitative structure–activity relationships (QSAR) for the nucleophilicity of trivalent boron compounds covering boryl fragments bonded to alkali and alkaline‐earth metals, to transition metals, and to sp3 boron units in diboron reagents. We used the charge of the boryl fragment (q[B]) and the boron p/s population ratio (p/s) to describe the electronic structures of boryl moieties, whereas the distance‐weighted volume (Vw) descriptor was used to evaluate the steric effects. The three‐term easy‐to‐interpret QSAR model showed statistical significance and predictive ability (r2=0.88, q2=0.83). The use of chemically meaningful descriptors has allowed identification of the factors governing the boron nucleophilicity and indicates that the most efficient nucleophiles are those with enhanced the polarization of the B−X bond towards the boron atom and reduced steric bulk. A detailed analysis of the potential energy surfaces of different types of boron substituents has provided insight into the mechanism and established an order of nucleophilicity for boron in B−X: X=Li>Cu>B(sp3)>Pd. Finally, we used the QSAR model to make a priori predictions of experimentally untested compounds.
Synthetische flüssige Kohlenwasserstoffe aus erneuerbaren Energien – Ergebnisse der Helmholtz Energieallianz
Authors: Moser Massimo , Pregger Thomas , Simon Sonja , König Daniel H. , Wörner Antje , Dietrich Ralph‐Uwe , Köhler Markus , Oßwald Patrick , Grohmann Jasper , Kathrotia Trupti , Eckel Georg , Schweitzer Daniel , Armbrust Nina , Dieter Heiko , Scheffknecht Günter , Kern Christoph , Thiessen Johannes , Jess Andreas , Aigner Manfred
Published: February 2017

Der vorliegende Beitrag stellt Arbeiten vor, die im Rahmen der dreijährigen Helmholtz‐Energieallianz Synthetische flüssige Kohlenwasserstoffe (SynKWS) – Speicher mit höchster Energiedichte durchgeführt wurden. Unter Einbezug technischer, prozessoptimierender und systemanalytischer Aspekte wurden ausgewählte Pfade für die Erzeugung von flüssigen, synthetischen Kohlenwasserstoffen aus erneuerbaren Energien und Biomassen untersucht und bewertet. Ergänzend erfolgte eine systemanalytische Bewertung synthetischer flüssiger Kohlenwasserstoffe in einem Energiesystem der Zukunft mit hohem Anteil erneuerbarer Energien.
Digital filters for low‐field NMR
Authors: Valori Andrea , Mitchell Jonathan , Fordham Edmund J.
Published: February 2017

We review the theory and operation of digital filters in modern nuclear magnetic resonance (NMR) spectrometers with fully digital receivers. Custom digital filters tailored for particular experimental requirements offer substantial improvements in signal‐to‐noise ratio (SNR), sensitivity, pulse sequence timing, and rejection of heteronuclear contamination. Pass‐band filters are designed and applied in the frequency domain. In high‐field imaging and spectroscopy, the impact of the filter is straight forward to visualize. However, low‐field NMR data acquired on bench‐top magnets are typically analyzed in the time‐domain where the influence of a frequency‐domain filter is not obvious and largely overlooked by end‐users. We provide practical guidance on the design and implementation of digital filters for bench‐top NMR applications, with examples of data acquired at 2.4 and 12.9 MHz. We discuss the compromise between speed (filter settling time) and noise rejection, and consider the special case of 19F signal contamination in 1H measurements. We suggest filter designs for narrow‐line liquid samples, broad‐line samples, and imaging.
Unique prevalence of oncogenic genetic alterations in young patients with lung adenocarcinoma
Authors: Tanaka Kosuke , Hida Toyoaki , Oya Yuko , Yoshida Tatsuya , Shimizu Junichi , Mizuno Tetsuya , Kuroda Hiroaki , Sakakura Noriaki , Yoshimura Kenichi , Horio Yoshitsugu , Sakao Yukinori , Yatabe Yasushi
Published: February 2017

BACKGROUND

Lung adenocarcinoma in the young is a rare entity, and the oncogenic genetic alterations (GAs) and clinical characteristics associated with this disease are poorly understood. Conversely, it has been demonstrated that young age at diagnosis defines unique biology in other cancers. For this report, the effects of young age on lung adenocarcinoma are reported.

METHODS

The authors retrospectively screened 1746 consecutive patients who were diagnosed with stage I through IV adenocarcinoma between 2009 and 2015 and identified 81 who were aged 40 years or younger at diagnosis. The clinical and genetic characteristics of this younger population were analyzed.

RESULTS

Of the 81 younger patients identified, 36 (44%) were men, 36 (44%) were never smokers, and the median age was 36 years (range, 26‐40 years). Thirty‐three patients (41%) harbored anaplastic lymphoma kinase (ALK) translocations, 24 (30%) had epidermal growth factor receptor (EGFR) mutations, and 2 (2%) had v‐Ki‐ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations. Rare oncogenic GAs also were studied in patients who had wild‐type ALK/EGFR/KRAS adenocarcinoma, including 4 patients with HER2 mutations, 2 with Ret proto‐oncogene (RET) translocations, and 2 with ROS proto‐oncogene 1 receptor tyrosine kinase (ROS1) translocations. Notably, oncogenic GAs (P < .001), ALK (P < .001) and ROS1 (P = .033) translocations, and HER2 mutations (P < .001) were associated with young age, and a similar trend was observed for RET translocations (P = .108). Younger patients who had adenocarcinoma without GAs had a significantly worse prognosis compared with older patients without GAs (overall survival, 8.9 vs 16.4 months; P < .001) and patients with GAs (24.9 months; P < .001).

CONCLUSIONS

Younger patients with adenocarcinoma have a distinctly unique prevalence of oncogenic GAs. Comprehensive oncogenic GA screening is especially recommended for personalized medicine strategies in this population. Cancer 2017;123:1731–1740. © 2017 American Cancer Society.
Burden of human metapneumovirus infections in patients with cancer: Risk factors and outcomes
Authors: El Chaer Firas , Shah Dimpy P. , Kmeid Joumana , Ariza‐Heredia Ella J. , Hosing Chitra M. , Mulanovich Victor E. , Chemaly Roy F.
Published: February 2017

BACKGROUND

Human metapneumovirus (hMPV) causes upper and lower respiratory tract infections (URIs and LRIs, respectively) in healthy and immunocompromised patients; however, its clinical burden in patients with cancer remains unknown.

METHODS

In a retrospective study of all laboratory‐confirmed hMPV infections treated at the authors’ institution between April 2012 and May 2015, clinical characteristics, risk factors for progression to an LRI, treatment, and outcomes in patients with cancer were determined.

RESULTS

In total, 181 hMPV infections were identified in 90 patients (50%) with hematologic malignancies (HMs), in 57 (31%) hematopoietic cell transplantation (HCT) recipients, and in 34 patients (19%) with solid tumors. Most patients (92%) had a community‐acquired infection and presented with URIs (67%), and 43% developed LRIs (59 presented with LRIs and 19 progressed from a URI to an LRI). On multivariable analysis, an underlying HM (adjusted odds ratio [aOR], 3.11; 95% confidence interval [CI], 1.12‐8.64; P = .029), nosocomial infection (aOR, 26.9; 95% CI, 2.79‐259.75; P = .004), and hypoxia (oxygen saturation [SpO2], ≤ 92%) at presentation (aOR, 9.61; 95% CI, 1.98‐46.57; P = .005) were identified as independent factors associated with LRI. All‐cause mortality at 30 days from hMPV diagnosis was low (4%), and patients with LRIs had a 10% mortality rate at day 30 from diagnosis; whereas patients with URIs had a 0% mortality rate.

CONCLUSIONS

hMPV infections in patients with cancer may cause significant morbidity, especially for those with underlying HM who may develop an LRI. Despite high morbidity and the lack of directed antiviral therapy for hMPV infections, mortality at day 30 from this infection remained low in this studied population. Cancer 2017;123:2329–2337. © 2017 American Cancer Society.
Lornoxicam Immediate‐Release Tablets: Formulation and Bioequivalence Study in Healthy Mediterranean Volunteers Using a Validated LC‐MS/MS Method
Authors: Zaid Abdel Naser , Mousa Ayman , Jaradat Nidal , Bustami Rana
Published: February 2017

This study aimed to demonstrate interchangeability between 2 lornoxicam tablet formulations under fasting conditions among Mediterranean Arabs by using a newly validated high‐pressure liquid chromatography–tandem mass spectrometry method. A single‐oral solid dosage form (8 mg/tablet), randomized, open‐label, 2‐way crossover study was conducted on 30 healthy male volunteers. Blood samples were collected prior to dosing and over a 24‐hour period, and the washout period was 9 days. Statistical comparison of the main pharmacokinetic parameters showed no significant difference between generic and branded products. The point estimates (ratios of geometric mean %) were 90.91, 96.34, and 94.86 for Cmax, AUC0–last, and AUC0–∞, respectively. The 90% confidence intervals were within the predefined limits of 80.00%–125.00%, as specified by the international guidelines. This study showed that both formulations met the regulatory criteria for bioequivalence.
Harvesting Hydrogen Gas from Air Pollutants with an Unbiased Gas Phase Photoelectrochemical Cell
Authors: Verbruggen Sammy W. , Van Hal Myrthe , Bosserez Tom , Rongé Jan , Hauchecorne Birger , Martens Johan A. , Lenaerts Silvia
Published: February 2017

The concept of an all‐gas‐phase photoelectrochemical (PEC) cell producing hydrogen gas from volatile organic contaminated gas and light is presented. Without applying any external bias, organic contaminants are degraded and hydrogen gas is produced in separate electrode compartments. The system works most efficiently with organic pollutants in inert carrier gas. In the presence of oxygen, the cell performs less efficiently but still significant photocurrents are generated, showing the cell can be run on organic contaminated air. The purpose of this study is to demonstrate new application opportunities of PEC technology and to encourage further advancement toward PEC remediation of air pollution with the attractive feature of simultaneous energy recovery and pollution abatement.
RepMChord: A novel replication approach for mobile Chord with reduced traffic overhead
Authors: Cherbal Sarra , Boukerram Abdellah , Boubetra Abdelhak
Published: February 2017

Structured peer‐to‐peer systems based on distributed hash table (DHT) have known a great popularity and performance since their appearance. They have experienced multiple improvements to increase the efficiency, like replication mechanism with different used methods and different objectives like increasing data availability or fitting to churn. Besides their benefits, these methods suffer from the excessive generated overhead in maintenance process. On the other side, we have the interest deployment of DHT overlay on mobile ad hoc network, which benefits from the infrastructure‐less architecture, but presents some shortcomings because of the limited bandwidth and energy batteries, what require a reduced overhead. Therefore, the aim of this work is to improve the lookup efficiency of DHT‐based Chord on mobile ad hoc network underlay. For that, we propose a novel replication mechanism based on data structure to determine the replica nodes, while avoiding the excessive generated overhead in maintenance process to cope with the problem of limited energy batteries. To evaluate the proposed method, we present an extensive simulation study that compares the work to another efficient replication method and to mobile basic Chord. The results show the efficiency of our approach in decreasing the lookup path, the maintenance overhead, and the energy consumption.
Enantioselective analysis of citalopram and demethylcitalopram in human whole blood by chiral LC–MS/MS and application in forensic cases
Authors: Johansen Sys Stybe
Published: February 2017

Citalopram is one of the most frequently used antidepressants in Denmark. It is marketed as a racemic mixture (50:50) of S‐ and R‐enantiomers as well as of the S‐enantiomer alone, which is the active enantiomer named escitalopram that processes the inhibitory effects. In this study, a chiral liquid chromatography–tandem mass spectrometry (LC–MS/MS) method is developed for the measurement of citalopram and demethylcitalopram enantiomers in whole blood and is applied to forensic cases. Whole blood samples (0.10 g) were extracted with butyl acetate after adjusting the pH with 2 M NaOH. The analytes were separated on a 250 × 4.6 mm Chirobiotic V, 5 μm column by isocratic elution with methanol:ammonia:acetic acid (1000:1:1) using an ultra‐high‐pressure liquid chromatography (UHPLC) system. Quantification was performed by tandem mass spectrometry (MS/MS) using multiple reaction monitoring (MRM) in the positive mode. The total chromatographic run time was 20 min. The limit of detection (LOD) and quantification (LOQ) were 0.001 and 0.005 mg/kg of all four enantiomers, respectively. Linear behaviour was obtained for all four enantiomers from LOQ to 0.50 mg/kg blood with absolute recoveries from 71 to 80%. The method showed an acceptable precision and accuracy as the obtained coefficient of variation, and bias values were ≤16% for all enantiomers. After the validation of the method, a correlation with the racemic method was assessed and found to be acceptable. Then, the method was successfully applied to authentic blood samples from forensic investigations demonstrating that escitalopram was less frequent than citalopram among all forensic cases. Copyright © 2017 John Wiley & Sons, Ltd.
Intraspecific functional diversity of common species enhances community stability
Authors: Wood Connor M. , McKinney Shawn T. , Loftin Cynthia S.
Published: February 2017

Common species are fundamental to the structure and function of their communities and may enhance community stability through intraspecific functional diversity (iFD). We measured among‐habitat and within‐habitat iFD (i.e., among‐ and within‐plant community types) of two common small mammal species using stable isotopes and functional trait dendrograms, determined whether iFD was related to short‐term population stability and small mammal community stability, and tested whether spatially explicit trait filters helped explain observed patterns of iFD. Southern red‐backed voles (Myodes gapperi) had greater iFD than deer mice (Peromyscus maniculatus), both among habitats, and within the plant community in which they were most abundant (their “primary habitat”). Peromyscus maniculatus populations across habitats differed significantly between years and declined 78% in deciduous forests, their primary habitat, as did the overall deciduous forest small mammal community. Myodes gapperi populations were stable across habitats and within coniferous forest, their primary habitat, as was the coniferous forest small mammal community. Generalized linear models representing internal trait filters (e.g., competition), which increase within‐habitat type iFD, best explained variation in M. gapperi diet, while models representing internal filters and external filters (e.g., climate), which suppress within‐habitat iFD, best explained P. maniculatus diet. This supports the finding that M. gapperi had higher iFD than P. maniculatus and is consistent with the theory that internal trait filters are associated with higher iFD than external filters. Common species with high iFD can impart a stabilizing influence on their communities, information that can be important for conserving biodiversity under environmental change.
Native herbivores and environmental heterogeneity as mediators of an exotic grass invasion
Authors: Ender Cody L. , Christian Caroline E. , Cushman J. Hall
Published: February 2017

Given that many exotic plant species throughout the world are having large ecological and economic effects, it is vital to understand the forces that mediate their success in novel landscapes. Both native herbivores and recipient ecosystems can have substantial effects on the performance of exotic plant species, and may interact with each other or vary in their effects over time. Unfortunately, few studies have evaluated the importance of these kinds of context‐dependent effects. Here, we use a 17‐year‐old exclosure experiment stratified across a coastal grassland in northern California to address the relative importance of a reintroduced mammalian herbivore, tule elk (Cervus canadensis nannodes), and environmental heterogeneity in mediating the growth, abundance, and recruitment of a problematic grass invader, Holcus lanatus. We found that elk reduced Holcus abundance, aboveground biomass, percent cover, frequency, and seedling recruitment, but that these effects often varied among habitat types, with effects being greater in open grasslands than shrub‐dominated grasslands. The performance of Holcus populations also varied significantly among habitat types, with the invader usually having the greatest success in Baccharis‐dominated grasslands. Our results suggest that environmental heterogeneity had much greater influence on Holcus success than elk, and that these effects were due largely to soil pH and moisture. The negative effects of elk on Holcus appeared after 4 years and did not intensify after an additional 13 years. Furthermore, despite their negative effects, these prominent herbivores did not prevent the spread of Holcus into previously uninvaded areas. Our research highlights the importance of assessing the individual and interactive effects of native herbivores and environmental heterogeneity on the success of invasive, exotic plant species. It emphasizes the reality that the negative effects of herbivores on exotic plant species will often vary across heterogeneous landscapes and may be insufficient to prevent the expansion of these invaders.
Modeling nonbreeding distributions of shorebirds and waterfowl in response to climate change
Authors: Reese Gordon C. , Skagen Susan K.
Published: February 2017

To identify areas on the landscape that may contribute to a robust network of conservation areas, we modeled the probabilities of occurrence of several en route migratory shorebirds and wintering waterfowl in the southern Great Plains of North America, including responses to changing climate. We predominantly used data from the eBird citizen‐science project to model probabilities of occurrence relative to land‐use patterns, spatial distribution of wetlands, and climate. We projected models to potential future climate conditions using five representative general circulation models of the Coupled Model Intercomparison Project 5 (CMIP5). We used Random Forests to model probabilities of occurrence and compared the time periods 1981–2010 (hindcast) and 2041–2070 (forecast) in “model space.” Projected changes in shorebird probabilities of occurrence varied with species‐specific general distribution pattern, migration distance, and spatial extent. Species using the western and northern portion of the study area exhibited the greatest likelihoods of decline, whereas species with more easterly occurrences, mostly long‐distance migrants, had the greatest projected increases in probability of occurrence. At an ecoregional extent, differences in probabilities of shorebird occurrence ranged from −0.015 to 0.045 when averaged across climate models, with the largest increases occurring early in migration. Spatial shifts are predicted for several shorebird species. Probabilities of occurrence of wintering Mallards and Northern Pintail are predicted to increase by 0.046 and 0.061, respectively, with northward shifts projected for both species. When incorporated into partner land management decision tools, results at ecoregional extents can be used to identify wetland complexes with the greatest potential to support birds in the nonbreeding season under a wide range of future climate scenarios.
Association between demographic, organizational, clinical, and socio‐economic characteristics and underutilization of cardiac resynchronization therapy: results from the Swedish Heart Failure Registry
Authors: Lund Lars H. , Braunschweig Frieder , Benson Lina , Ståhlberg Marcus , Dahlström Ulf , Linde Cecilia
Published: February 2017

Aims

Cardiac resynchronization therapy (CRT) improves outcomes in heart failure (HF) but may be underutilized. The reasons are unknown.

Methods and results

We linked the Swedish Heart Failure Registry to national registries with ICD‐10 (International Classification of Diseases‐10th Revision) co‐morbidity diagnoses and demographic and socio‐economic data. In patients with EF ≤39% and NYHA II–IV, we assessed prevalence of CRT indication and CRT use. In those with CRT indication, we assessed the association between 37 potential baseline covariates and CRT non‐use using multivariable generalized estimating equation (GEE) models. Of 12 807 patients (mean age 71 ± 12 years, 28% female), 841 (7%) had CRT, 3094 (24%) had an indication for but non‐use of CRT, and 8872 (69%) had no indication. Important variables independently associated with CRT non‐use were: HF duration <6 months [risk ratio (RR) 1.21, 95% confidence interval (CI) 1.17–1.24]; non‐cardiology planned follow‐up (RR 1.14, 95% CI 1.09–1.18); age >75 years (RR 1.13, 95% CI 1.09–1.18); non‐cardiology care at baseline (RR 1.10, 95% CI 1.07–1.14); small‐town non‐university centre (RR 1.08, 95% CI 1.05–1.12); female sex (RR 1.07 95% CI 1.03–1.10) (all P < 0.05); as was absence of AF, living alone; psychiatric diagnosis; smoking; and non‐use of HF drugs. Education, income, cancer, or HF characteristics were not independently associated with CRT non‐use.

Conclusion

In this population‐wide HF registry, CRT was underutilized. Non‐use was associated mostly with demographic and organizational, but not clinical or socio‐economic factors. This calls for programmes to raise awareness of CRT indications and improve access and referrals to cardiology specialists.
A Thermodynamic Study of Aqueous 1‐Allyl‐3‐Methylimidazolium Formate Ionic Liquid as a Tailored Sorbent for Carbon Dioxide Separation
Authors: Xie Yujiao , Raut Dilip G. , Samikannu Rakesh , Mikkola Jyri‐Pekka , Ji Xiaoyan
Published: February 2017

In this work, aqueous 1‐allyl‐3‐methylimidazolium formate ([Amim][HCOO]) was studied as a potential sorbent for CO2 separation. The density and viscosity of aqueous [Amim][HCOO] were measured at temperatures ranging from 293.15 to 333.15 K at atmospheric pressure. The solubility of CO2 and CH4 in dry [Amim][HCOO] as well as the CO2 solubility in aqueous [Amim][HCOO] were measured at pressures up to 1.8 MPa and temperatures of 298.2, 313.2, and 333.2 K. The results showed that the density and viscosity of aqueous [Amim][HCOO] as well as the CO2 solubility in aqueous [Amim][HCOO] decreased upon increasing the water concentration and temperature. The viscosity was very sensitive to the water concentration. The experimental density and viscosity of aqueous [Amim][HCOO] were fitted to semiempirical equations, and the excess molar volume and viscosity deviations were calculated to investigate the interaction between the [Amim][HCOO] ionic liquid and water. The experimental vapor–liquid equilibrium was represented with the nonrandom two‐liquid and Redlich–Kwong model. The model parameters can be further implemented into Aspen Plus software to conduct process simulations.
Petroleum generation and expulsion in middle Permian Lucaogou Formation, Jimusar Sag, Junggar Basin, northwest China: assessment of shale oil resource potential
Authors: Zhou Liming , Pang Xiongqi , Wu Luya , Kuang Lichun , Pang Hong , Jiang Fujie , Bai Hua , Peng Junwen , Pan Zhihong , Zheng Dingye
Published: February 2017

Shale oil exploration of the Permian Lucaogou Formation (P2l) has greatly advanced in the Jimusar Sag in the Junggar Basin. However, despite the strong exploration prospects of shale oil resources, the potential of shale oil resources in the Junggar Basin has been insufficiently assessed. This study performs systematical evaluation of P2l source rocks in the Jimusar Sag and proposes an improved hydrocarbon generation potential method to assess the hydrocarbon generation and expulsion characteristics and evaluates the shale oil resource potential of the P2l source rocks in the Jimusar Sag. The results show that the P2l source rocks are thick (up to 200 m) and are distributed over a wide area (up to 1200 km2) in the study region. It contains high TOC (2%–5%), characterized by dominantly type I and type II kerogen. The source rocks are in the low mature–mature stage, and possess good conditions for generation of hydrocarbons. The P2l source rocks reached the hydrocarbon expulsion threshold at a thermal maturity of 0.8% vitrinite reflectance. The efficiency of hydrocarbon expulsion of the source rock is 34%. The amounts of hydrocarbons generated and expelled were 65 × 108 t. Based on the above information, the shale oil resources potential is calculated to be 43 × 108 t, indicating very good shale oil resource prospect in the P2l source rocks of the Jimusar Sag. Copyright © 2017 John Wiley & Sons, Ltd.
Zircon U–Pb ages and Hf isotope of the granitoids from the Xingwen porphyry molybdenum deposit in the Xiaoxing'an Range – Zhangguangcai Range metallogenic belt, NE China
Authors: Zeng Qingdong , Wang Ruiliang , Cheng Guohua , Yang Yueheng
Published: February 2017

The newly discovered Xingwen porphyry Mo deposit is located in the most southern segment of the Xiaoxing'an Range–Zhangguangcai Range metallogenic belt (XZMB), NE China. The Mo deposit occurs with a granitic complex consisting of monzogranite, porphyritic granite and felsite porphyry. The Zircon U–Pb ages of monzogranite, porphyritic granite and felsite porphyry are 170.3 ± 2.1, 168.5 ± 2.5, and 166.7 ± 1.6 Ma, respectively. The inherited zircons from the monzogranite and porphyritic granite yield U–Pb ages of 239.8 ± 5.8 and 249.4 ± 6.2 Ma, respectively. These ages reveal that the Mo mineralization in the most southern segment of the XZMB took place in the Middle Jurassic, and is consistent with the epoch of the largest Daheishan Mo district in the XZMB. In contrast, Triassic ages of the inherited zircons are consistent with the ages of the Triassic magmatic activities along the E–W trending tectono‐magmatic belt in the northern margin of the North China Craton. The εHf(t) of the monzogranite, porphyritic granite and felsite porphyry change from −17.1 to +6.7 , −16.9 to +2.9, −5.94 to −0.90, respectively. The Hf isotopic compositions indicate that old crustal source, juvenile crustal source or depleted mantle contributed to their origin. When compared with the granite in Daheishan Mo district in XZMB, the εHf(t) probably indicates that the granitic complex in the margin of the Central Asia Orogenic Belt may have more old crustal materials than the granitic complex in the inner region of the Central Asia Orogenic Belt. Copyright © 2017 John Wiley & Sons, Ltd.
A multistate population‐based analysis of linked maternal and neonatal discharge records to identify risk factors for neonatal brachial plexus injury
Authors: Freeman Michael D. , Goodyear Shaun M. , Leith Wendy M.
Published: February 2017

Objective

To evaluate the interaction and contribution of maternal and fetal risk factors associated with neonatal brachial plexus injury (BPI).

Methods

In a case–control study, matched maternal and neonatal discharge records were accessed from US State Inpatient Databases for New Jersey (2010–2012), Michigan (2010–2011), and Hawaii (2010–2011). Univariate and multivariate logistic regressions were used to evaluate associations between risk factors and BPI. Area under the receiver operating characteristic curve was used to build predictive models, including two stratified models evaluating deliveries among obese and diabetic cohorts.

Results

Among 376 325 deliveries, BPI was diagnosed in 274 (0.1%). Significant BPI risk factors included maternal obesity (odds ratio [OR] 2.7, 95% confidence interval [CI] 1.7–4.4), maternal diabetes (OR 4.6, 95% CI 3.0–7.0), use of forceps (OR 4.6, 95% CI 2.3–9.0), and vacuum assistance (OR 2.3, 95% CI 1.7–3.3). After adjusting for shoulder dystocia and other predictive factors, cesarean reduced the risk of BPI by 88% (OR 0.1, 95% CI 0.07–0.2). When stratified by obesity and diabetes, the ORs for BPI increased significantly for macrosomia, forceps, and vacuum assistance.

Conclusion

The analysis confirms and quantifies more precisely the impact of risk factors for neonatal BPI, and provides a reliable basis for evidence‐based clinical decision‐making models.
The clinical implementation of primary HPV screening
Authors: Mariani Luciano , Igidbashian Sarah , Sandri Maria Teresa , Vici Patrizia , Landoni Fabio
Published: February 2017

Objective

To evaluate, from a gynecology perspective, the transition from cytology‐based HPV screening to primary HPV screening.

Methods

Studies examining switching from cytology‐based screening to primary HPV‐DNA testing with triaging of patients with positive test results were retrieved and reviewed, with a particular focus on screening in an Italian setting.

Results

The increased complexity of patient‐management decisions when implementing HPV‐based screening was a critical issue discussed in the literature. The change in strategy represents a paradigm shift in moving from a medical perspective of identifying the disease in individual patients, to a public‐healthcare perspective of excluding HPV from the healthy population and identifying a small sub‐group of individuals at increased risk of HPV.

Conclusion

With knowledge about HPV screening evolving rapidly, new programs and related algorithms need to be sufficiently flexible to be adjusted according to ongoing research and the validation of new assays. The establishment of a national working group (including epidemiologists, gynecologists, pathologists, and healthcare providers) will be necessary to properly implement and govern this important technical and cultural transition.
Angiogenesis mediators in women with idiopathic heavy menstrual bleeding
Authors: Elkilani Osama A. , Soliman Mohamed A.
Published: February 2017

Objective

To assess the relationship between stromal cell‐derived factor 1 (SDF‐1) and mature endothelial cells in patients with heavy menstrual bleeding (HMB).

Methods

In a prospective observational study, women with idiopathic HMB and control individuals attending Menoufia University Hospital, Egypt, between August 2015 and January 2016 were enrolled. The inclusion criteria were a regular menstrual cycle, a normal coagulation study, and no anomalous ultrasonographic or hysteroscopic findings. Blood samples were collected during different phases of the menstrual cycle (day 5, ovulation, day 24) for measurement of the SDF‐1 plasma level (by enzyme‐linked immunosorbent assay) and for quantification of mature endothelial cells (by flow cytometry).

Results

Overall, 20 women with HMB and 10 control individuals were enrolled. The SDF‐1 level was significantly lower in the HMB group than in the control group during all phases of the menstrual cycle (P≤0.05 for all). The percentage of mature endothelial cells was significantly higher in the HMB group than among controls (P<0.001 for all). The SDF‐1 level and the percentage of endothelial cells were negatively correlated throughout the cycle (P<0.001 for all).

Conclusion

Some mediators of angiogenesis, such as SDF‐1 and endothelial cells, are disturbed in women with idiopathic HMB.