bluuebunny/crossref_metadata_2025 huggingface dataset:
La pédagogie : une source de conflits entre chefs d’établissement et enseignants ? Le cas du secondaire en France
Authors: Combaz Gilles , Cacouault-Bitaud Marlaine
Published: September 2014

En France, depuis le début des années 2000, les personnels de direction de l’enseignement du second degré sont invités par les autorités de tutelle à jouer un rôle plus déterminant qu’auparavant dans le registre pédagogique. Cette orientation pose la question de leur légitimité dans ce domaine. L’article montre qu’elle n’est que partiellement reconnue par les enseignants, qui leur contestent cette compétence. À partir d’une enquête nationale qui a permis d’interroger par questionnaire 332 chefs d’établissement, la recherche vise à identifier et à analyser les conflits qui opposent les deux catégories de personnels. Leur mésentente peut affecter le fonctionnement harmonieux de l’établissement.
L’expérience scolaire d’élèves issus de l’immigration dans trois écoles pluriethniques de Montréal
Authors: Potvin Maryse , Audet Geneviève , Bilodeau Angèle
Published: September 2014

Cet article reprend les principaux constats d’une étude portant sur l’expérience socioscolaire de trois groupes de jeunes issus de l’immigration dans trois écoles en milieu défavorisé à Montréal. À partir de leur propre analyse, les jeunes dégagent les différents facteurs, relations sociales et enjeux significatifs de leur expérience et donnent à celle-ci des significations normatives, stratégiques et éthiques. Leur analyse met en évidence l’impact des processus migratoires, culturels et sociaux de leur expérience socioscolaire. L’importance de faire une lecture fine et expérientielle des facteurs liés à la pluriethnicité ou à la défavorisation est finalement mise de l’avant.
Identifier le verbe : élaboration des connaissances par les élèves en classe
Authors: Gauvin Isabelle , Boivin Marie-Claude
Published: September 2014

Cet article décrit les connaissances grammaticales relatives à la notion de verbe, élaborées par des élèves de 12-13 ans au cours de l’apprentissage de l’accord du verbe. Nos données, recueillies grâce à la captation vidéo en classe, indiquent que les élèves utilisent plus de connaissances procédurales que déclaratives pour identifier le verbe et que le recours à des connaissances marginales diminue après l’institutionnalisation des savoirs. Toutefois, les connaissances antérieures des élèves sont prégnantes : elles résistent à l’institutionnalisation de savoirs nouveaux. Nous discutons des implications des résultats pour la transposition didactique externe, en soulignant l’intérêt de l’enseignement des savoirs procéduraux.
Fristverlängerung zur Anspruchsbegründung nach Widerspruch gegen den Mahnbescheid?
Authors: Hogenschurz Johannes
Published: September 2014

Die Angst des Anwalts vor der Fristversäumung führt reflexartig zum Fristverlängerungsantrag. Der folgende Beitrag zeigt, warum dieser Aufwand bei der Frist für die Anspruchsbegründung gem. § 697 Abs. 1 S. 1 ZPO nach vorangegangenem Mahnbescheid und Widerspruch schlecht investiert ist und zur folgenlosen Ablehnung führen muss.
Vermögenssorge für minderjährige Kinder Unter besonderer Berücksichtigung der Trennung der Eltern
Authors: Jordans Roman
Published: September 2014

Vertragsabschlüsse (v.a. Onlineverträge und Fitnessverträge) mit minderjährigen Kindern sind in der Praxis keine Seltenheit. Grundsätzlich werden minderjährige Kinder bei Vertragsabschlüssen im Rahmen der Vermögenssorge durch ihre Eltern vertreten und der Vertrag bedarf nach §§ 107, 108 BGB der elterlichen Zustimmung. Doch es gibt eine unüberschaubare Fülle von Einzelfällen: So soll eine Tätowierung einer 17-jährigen vom „Taschengeldparagraphen“ § 110 BGB erfasst sein (AG München v. 17.3.2011 - 213 C 917/11, NJW 2012, 2452); nicht jedoch das Herunterladen eines Klingeltons bei einem Prepaid-Mobiltelefon (AG Düsseldorf v. 2.8.2006 - 52 C 17756/05, MMR 2007, 404). Die Frage nach der Verfassungsgemäßheit des Sonnenstudioverbots hat bereits das BVerfG beschäftigt (BVerfG v. 21.12.2011 - 1 BvR 2007/11, NJW 2012, 1062). Darüber hinaus sind Besonderheiten zu beachten, wenn die Eltern minderjähriger Kinder nicht miteinander verheiratet sind bzw. sich die Eltern minderjähriger Kinder trennen bzw. scheiden lassen. Für Vertragspartner Minderjähriger ist gerade in diesen Fällen wichtig zu wissen, wer im Namen des minderjährigen Kindes handeln darf. Der folgende Beitrag geht auf verschiedene Fallgruppen der elterlichen Sorge sowie die Ausübung des gemeinsamen Sorgerechts ein und erläutert die Rechtsfolgen für Vertragsabschlüsse.
Theoretical Approaches to Digital Services and Digital Democracy: The Merits of the Contextual New Medium Theory Model
Authors: Hoff Jens , Scheele Christian Elling
Published: September 2014

This article develops a theoretical framework that can be used to analyze all types of political and administrative web applications Through a discussion and criticism of social construction of technology (SCOT), an earlier version of this model based on new medium theory (the NeMT model), Leavitt's “diamond” and Jane Fountain's “technology enactment” model, the article arrives at a model, called the “Contextual NeMT” model. This model focuses on how the specific affordances of the Internet are translated into specific political and/or administrative practices, and how these practices are produced through the interplay between and among discourses, actors, and technology. Finally, the article demonstrates the merits of the model by using it in the analysis of the digital practices of the municipality of Odder, a frontrunner in the development of digital services and e‐democracy in Denmark.
A drought index accounting for snow
Authors: Staudinger Maria , Stahl Kerstin , Seibert Jan
Published: September 2014

The Standardized Precipitation Index (SPI) is the most widely used index to characterize droughts that are related to precipitation deficiencies. However, theSPIdoes not always deliver the relevant information for hydrological drought management particularly in snow‐influenced catchments. If precipitation is temporarily stored as snow, then there is a significant difference between meteorological and hydrological drought because the delayed release of melt water to the stream. We introduce an extension to theSPI, the Standardized Snow Melt and Rain Index (SMRI), that accounts for rain and snow melt deficits, which effectively influence streamflow. TheSMRIcan be derived without snow data, using temperature and precipitation to model snow. The value of the new index is illustrated for seven Swiss catchments with different degrees of snow influence. In particular for catchments with a larger component of snowmelt in runoff generation, theSMRIwas found to be a worthwhile complementary index to theSPIto characterize streamflow droughts.
Liquid iron‐sulfur alloys at outer core conditions by first‐principles calculations
Authors: Umemoto Koichiro , Hirose Kei , Imada Saori , Nakajima Yoichi , Komabayashi Tetsuya , Tsutsui Satoshi , Baron Alfred Q.R.
Published: September 2014

We perform first‐principles calculations to investigate liquid iron‐sulfur alloys (Fe, Fe56S8, Fe52S12, and Fe48S16) under high‐pressure and high‐temperature (150–300 GPa and 4000–6000 K) conditions corresponding to the Earth's outer core. Considering only the density profile, the best match with the preliminary reference Earth model is by liquid Fe–14 wt % S (Fe50S14), assuming sulfur is the only light element. However, its bulk sound velocity is too high, in particular in the deep outer core, suggesting that another light component such as oxygen is required. An experimental check using inelastic X‐ray scattering shows good agreement with the calculations. In addition, a present study demonstrates that the Birch's law does not hold for liquid iron‐sulfur alloy, consistent with a previous report on pure liquid iron.
Moral disengagement in the legitimation and realization of aggressive behavior in soccer and ice hockey
Authors: Traclet Alan , Moret Orlan , Ohl Fabien , Clémence Alain
Published: September 2014

The aim of the present study was to verify that the level of tolerance for aggression is higher in a collective context than in an individual context (polarization effect), and to test the association between moral disengagement, team and self‐attitudes toward aggression, and tolerance and realization of aggressive acts in Swiss male soccer and ice hockey. In individual or collective answering conditions, 104 soccer and 98 ice hockey players viewed videotaped aggressive acts and completed a questionnaire, including measures of the perceived legitimacy of videotaped aggression, of the teammates, coach, and self attitudes toward transgressions (modified TNQ), of the moral disengagement in sport (modified MDSS‐S), and of self‐reported aggressive behavior. A multilevel analysis confirmed a strong polarization effect on the perception of instrumental aggression, the videotaped aggressive acts appearing more tolerated in the collective than in the individual answering condition. Using a structural equation modeling, we found that the moral disengagement, which mediates the effects of perceived coach and ego attitudes toward transgressions, correlates positively with the tolerance of hostile aggression within teams, and with the level of aggressive acts reported by the participants. Aggr. Behav. Aggr. Behav. 42:123–133, 2015. © 2014 Wiley Periodicals, Inc.
Theranostic USPIO‐Loaded Microbubbles for Mediating and Monitoring Blood‐Brain Barrier Permeation
Authors: Lammers Twan , Koczera Patrick , Fokong Stanley , Gremse Felix , Ehling Josef , Vogt Michael , Pich Andrij , Storm Gert , van Zandvoort Marc , Kiessling Fabian
Published: September 2014

Efficient and safe drug delivery across the blood‐brain barrier (BBB) remains one of the major challenges of biomedical and (nano‐) pharmaceutical research. Here, it is demonstrated that poly(butyl cyanoacrylate)‐based microbubbles (MB), carrying ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles within their shell, can be used to mediate and monitor BBB permeation. Upon exposure to transcranial ultrasound pulses, USPIO‐MB are destroyed, resulting in acoustic forces inducing vessel permeability. At the same time, USPIO are released from the MB shell, they extravasate across the permeabilized BBB and they accumulate in extravascular brain tissue, thereby providing non‐invasive R
2*‐based magnetic resonance imaging information on the extent of BBB opening. Quantitative changes in R
2* relaxometry are in good agreement with 2D and 3D microscopy results on the extravascular deposition of the macromolecular model drug fluorescein isothiocyanate (FITC)‐dextran into the brain. Such theranostic materials and methods are considered to be useful for mediating and monitoring drug delivery across the BBB and for enabling safe and efficient treatment of CNS disorders.
Engineering Acidithiobacillus ferrooxidans growth media for enhanced electrochemical processing
Authors: Li Xiaozheng , Mercado Roel , Berlinger Sarah , Banta Scott , West Alan C.
Published: September 2014

The chemolithoautotroph Acidithiobacillus ferrooxidans has been proposed as a potential electrofuel synthetic platform, and its growth medium is engineered to increase its conductivity and energy density, thereby improving viability of the process. The ion V3+ is used as an indirect electron supplier together with Fe2+ to grow A. ferrooxidans to increase the energy density of the medium, overcoming the Fe3+ solubility limit. A medium containing 10 mM Fe2+ with 60 mM V3+ was able to support cell growth to a final cell concentration very similar to medium of 70 mM Fe2+. Integration of the biological process with an electrochemical reactor requires, for economical operation, a medium with high ionic conductivity. This is achieved by the addition of salt, and Mg2+ was found to be least toxic to the bacterium. A concentration of 500 mM Mg2+ is optimal considering constraints on bacterial growth and electrochemistry. © 2014 American Institute of Chemical Engineers AIChE J 60: 4008–4013, 2014
The conservation value of degraded forests for agile gibbonsHylobates agilis
Authors: Lee David C. , Powell Victoria J. , Lindsell Jeremy A.
Published: September 2014

All gibbon species are globally threatened with extinction yet conservation efforts are undermined by a lack of population and ecological data. Agile gibbons (Hylobates agilis) occur in Sumatra, Indonesia and adjacent mainland Southeast Asia. Population densities are known from four sites (three in Sumatra) while little is known about their ability to tolerate habitat degradation. We conducted a survey of agile gibbons in Harapan Rainforest, a lowland forest site in Sumatra. The area has been severely degraded by selective logging and encroachment but is now managed for ecosystem restoration. We used two survey methods: an established point count method for gibbons with some modifications, and straight line transects using auditory detections. Surveys were conducted in the three main forest types prevalent at the site: high, medium, and low canopy cover secondary forests. Mean group density estimates were higher from point counts than from line transects, and tended to be higher in less degraded forests within the study site. We consider points more time efficient and reliable than transects since detectability of gibbons was higher from points per unit effort. We recommend the additional use of Distance sampling methods to account for imperfect detection and provide other recommendations to improve surveys of gibbons. We estimate that the site holds at least 6,070 and as many as 11,360 gibbons. Our results demonstrate that degraded forests can be extremely important for the conservation of agile gibbons and that efforts to protect and restore such sites could contribute significantly to the conservation of the species. Am. J. Primatol. 77:76–85, 2015. © 2014 Wiley Periodicals, Inc.
Sleep in the spider monkey (Ateles geoffroyi): A semi‐restrictive, non‐invasive, polysomnographic study
Authors: Cruz‐Aguilar Manuel Alejandro , Ayala‐Guerrero Fructuoso , Jiménez‐Anguiano Anabel , Santillán‐Doherty Ana María , García‐Orduña Francisco , Velázquez‐Moctezuma Javier
Published: September 2014

The normal sleep patterns of the spider monkey (Ateles geoffroyi) have not been described yet. The objective of this study was to characterize the electrophysiological patterns, sleeping postures, and sleep‐wake cycle in semi‐restricted spider monkeys. Continuous 24‐hr polysomnographic (PSG) recordings, involving simultaneous recording of non‐invasive electroencephalographic (EEG), electro‐oculographic (EOG), and electromyographic (EMG) activities, were carried out in captive monkeys living in outdoor rainforest enclosures. Electrode placement was done according to the human international 10–20 system. Specific behaviors displayed by monkeys during the sleep‐wake cycles were correlated with the PSG recordings. The nycthemeral distribution of the sleep‐wake cycle was also calculated. The results show that electrophysiological N‐REM sleep patterns in spider monkeys are similar to those observed in other primates, including human beings. Furthermore, a vertical semi‐fetal posture was observed during N‐REM and REM sleep phases. The amount of nocturnal sleep was significantly higher than that of the diurnal period, showing that the spider monkey is a diurnal primate. An outstanding finding was the absence of muscular atonia during the spider monkey's REM sleep, which suggests that arboreal primates have developed a neuromuscular mechanism specialized for sleeping in a vertical posture. Am. J. Primatol. 77:200–210, 2015. © 2014 Wiley Periodicals, Inc.
A novel method for capturing and monitoring a small neotropical primate, the squirrel monkey (Saimiri collinsi)
Authors: Stone Anita I. , Castro Paulo H. G. , Monteiro Frederico O. B. , Ruivo Luana P. , de Sousa e Silva Júnior José
Published: September 2014

Squirrel monkeys (genus Saimiri) are agile, arboreal primates that are seldom captured in the wild due to their small body size (<1 kg) and large, non‐cohesive social groups (40–50 individuals). However, long‐term studies on these primates often require captures and permanent identification of individuals, in order to monitor their behavior and health. Here we report on a novel trapping method successfully used to capture Saimiri collinsi, in Eastern Amazonia, Brazil. Our objective was to capture as many individuals as possible from one social group of approximately 50 individuals, ranging over 150 ha of terra firme forest. Captures occurred in November and December 2013. We habituated animals to feed on a large platform located in a 123.5 m2 area enclosed by a green net (3 m high). Multiple individuals could freely enter and exit the area via four ropes affixed from surrounding trees to the platform. Once individuals were feeding inside the netted area on selected trapping days, the ropes were dropped remotely, eliminating their escape routes. We successfully trapped 21 different individuals of the social group (14 adults and 7 immatures) with this method. We conclude that this is a conceptually simple, effective method for trapping squirrel monkeys in most habitats, and possibly other small arboreal primates that live in large social groups. The present method was more effective than previous methods utilized to capture squirrel monkeys in the field, and has the advantages of: allowing for safe capture of several individuals simultaneously; enabling re‐captures; releasing of animals as a group at the site of capture; use of soft netting which facilitates safe capture of the monkeys. Am. J. Primatol. 77:239–245, 2015. © 2014 Wiley Periodicals, Inc.
Thermal and chemical stabilization of ethylene/vinyl acetate/vinyl alcohol (EVA‐OH) terpolymers under nitroplasticizer environments
Authors: Yang Dali , Hubbard Kevin M. , Henderson Kevin C. , Labouriau Andrea
Published: September 2014

In this study, we compare the aging behaviors of cross‐linked ethylene/vinyl acetate/vinyl alcohol terpolymers, also referred to as EVA‐OH, when they are either immersed in nitroplasticizer (NP) liquid or exposed to NP vapor at different temperatures. While thermogravimetric analysis and differential scanning calorimetry are used to probe the thermal stability of aged NP and polymers, Fourier transform infrared, gel permeation chromatography, ultra‐violet/vis, and nuclear magnetic resonance are used to probe their structural changes over the aging process. The study confirms that NP degrades through CN cleavage, and releases HONO molecules at a slightly elevated temperature (<75°C). As these molecules accumulate in the vapor phase, they react among themselves to create an acidic environment. Therefore, these chemical constituents in the NP vapor significantly accelerate the hydrolysis of EVA‐OH polymer. When the hydrolysis occurs in both vinyl acetate and urethane groups and the scission at the cross‐linker progresses, EVA‐OH becomes vulnerable to further degradation in the NP vapor environment. Through the comprehensive characterization, the possible degradation mechanisms of the terpolymers are proposed. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41450.
Cranial neural crest cell contribution to craniofacial formation, pathology, and future directions in tissue engineering
Authors: Snider Taylor Nicholas , Mishina Yuji
Published: September 2014

This review provides an overview of the state and future directions of development and pathology in the craniofacial complex in the context of Cranial Neural Crest Cells (CNCC). CNCC are a multipotent cell population that is largely responsible for forming the vertebrate head. We focus on findings that have increased the knowledge of gene regulatory networks and molecular mechanisms governing CNCC migration and the participation of these cells in tissue formation. Pathology due to aberrant migration or cell death of CNCC, termed neurocristopathies, is discussed in addition to craniosynostoses. Finally, we discuss tissue engineering applications that take advantage of recent advancements in genome editing and the multipotent nature of CNCC. These applications have relevance to treating diseases due directly to the failure of CNCC, and also in restoring tissues lost due to a variety of reasons. Birth Defects Research (Part C) 102:324–332, 2014. © 2014 Wiley Periodicals, Inc.
The capacity of neural crest‐derived stem cells for ocular repair
Authors: Liu Bo , Hunter Daniel J. , Smith Andrew A. , Chen Serafine , Helms Jill A.
Published: September 2014

Whether it is due to a particular epigenetic signature, or some other component of an embryonic differentiation program, accumulating evidence indicates that the origins of a stem cell has a profound impact on the potential of a tissue to regenerate and repair. Here, we focus on Müller glia, long considered the stem cells of the retina, and their surprising derivation from the neural crest. Whether the multipotent properties of a subset of Müller glia is associated with their neural crest origin remains a tantalizing possibility. Birth Defects Research (Part C) 102:299–308, 2014. © 2014 Wiley Periodicals, Inc.
A kinetic study of the enhancement of solution chemiluminescence of glyoxylic acid oxidation by manganese species
Authors: Otamonga Jean‐Paul , Abdel‐Mageed Amal , Agater Irena B. , Jewsbury Roger A.
Published: September 2014

In order to study the mechanism of the enhancement of solution chemiluminescence, the kinetics of the decay of the oxidant and the chemiluminescence emission were followed for oxidations by permanganate, manganese dioxide sol and Mn3+(aq) of glyoxylic acid, using stopped‐flow spectrophotometry. Results are reported for the glyoxylic acid oxidized under pseudo first‐order conditions and in an acidic medium at 25 °C. For permanganate under these conditions, the decay is sigmoidal, consistent with autocatalysis, and for manganese dioxide sol and Mn3+ it is pseudo first order. The effects of the presence of aqueous formaldehyde and Mn2+ were observed and a fit to a simple mechanism is discussed. It is concluded that chemiluminescent enhancement in these systems is best explained by reaction kinetics. Copyright © 2014 John Wiley & Sons, Ltd.
Effect of replacement of Ca by Zn on the structure and optical property of CaTiO3:Eu3+ red phosphor prepared by sol‐gel method
Authors: Wang Yulong , Zhang Wentao , Zhang Peicong , Li Junfeng , Long Jianping
Published: September 2014

Eu3+‐doped calcium titanate red phosphors, Ca1‐xZnxTiO3:Eu3+, were prepared by the sol‐gel method. The structure of prepared Ca1‐xZnxTiO3:Eu3+ phosphors were investigated by X‐ray diffraction and infrared spectra. Due to the 5D0 → 7F1–3 electron transitions of Eu3+ ions, photoluminescence spectra showed a red emission at about 619 nm under excitation of 397 nm and 465 nm, respectively. When zinc was added to the host, the luminescent intensity of Ca1‐xZnxTiO3:Eu3+ was markedly improved several fold compared with that of CaTiO3:Eu3+. Ca0.9Zn0.1TiO3:Eu3+ also had higher luminescence intensity than the commercially available Y2O3:Eu3+ phosphors under UV light excitation. Copyright © 2014 John Wiley & Sons, Ltd.
Bone marrow mesenchymal stem cells protect alveolar macrophages from lipopolysaccharide‐induced apoptosis partially by inhibiting the Wnt/β‐catenin pathway
Authors: Li Bin , Zhang Hongwu , Zeng Mian , He Wanmei , Li Ming , Huang Xubin , Deng David Y. B. , Wu Jianfeng
Published: September 2014

Apoptosis of alveolar macrophages (AMs) plays a pathogenic role in acute lung injury (ALI) and its severe type, acute respiratory distress syndrome (ARDS). Mesenchymal stem cells (MSCs) are promising therapeutic cells for preventing apoptosis and eliminating cellular injury. We investigated the effects of rat bone marrow mesenchymal stem cells (BMSCs) on lipopolysaccharide (LPS)‐induced apoptosis in AMs using transwell experiments, and examined the underlying mechanisms LPS induced AMs apoptosis in a dose‐ and time‐dependent fashion, whereas BMSCs reduced AMs apoptosis when co‐cultured at appropriate ratios. BMSCs decreased expression of cleaved caspase‐3 and the pro‐apoptotic protein, Bax, whilst increased levels of the anti‐apoptotic protein, Bcl‐2, prolonging the lifespan of AMs in vitro. Promotion of AMs survival by BMSCs required down‐regulation of p‐GSK‐3β and β‐catenin in AMs. The anti‐apoptosis action of BMSCs was reversed by SB216763, a specific inhibitor of GSK‐3β that also activates Wnt/β‐catenin signaling. In conclusion, BMSCs can attenuate AM apoptosis partially by suppressing the Wnt/β‐catenin pathway.
Finite‐time stability and boundedness of switched nonlinear time‐delay systems under state‐dependent switching
Authors: Dong Yali , Yang Fengwei
Published: September 2014

This article investigates the finite‐time stability, stabilization, and boundedness problems for switched nonlinear systems with time‐delay. Unlike the existing average dwell‐time technique based on time‐dependent switching strategy, largest region function strategy, that is, state‐dependent switching control strategy is adopted to design the switching signal, which does not require the switching instants to be given in advance. Some sufficient conditions which guarantee finite‐time stable, stabilization, and boundedness of switched nonlinear systems with time‐delay are presented in terms of linear matrix inequalities. Detail proofs are given using multiple Lyapunov‐like functions. A numerical example is given to illustrate the effectiveness of the proposed methods. © 2014 Wiley Periodicals, Inc. Complexity 21: 267–275, 2015
Synthesis of 1,2‐Diols and Their Base‐Initiated Rearrangement to Butyrolactones
Authors: Moliterno Mauro , Margarita Cristiana , Panarello Silvia , Salvio Riccardo , Bella Marco
Published: September 2014

1,2‐Diols 3 have been synthesized by the aldol addition of hydroxy esters 1 to propargyl aldehydes 2 in dichloromethane. These 1,2‐diols undergo a base‐initiated rearrangement under mild conditions in methanol with an unusual 1,2‐alkyl shift to afford interesting α,β‐unsaturated γ‐butyrolactones 4. A possible mechanism is postulated on the basis of experimental evidence and the results of DFT calculations.
Capillary electrochromatographic fast enantioseparation based on a chiral metal–organic framework
Authors: Fei Zhi‐Xin , Zhang Mei , Xie Sheng‐Ming , Yuan Li‐Ming
Published: September 2014

Metal–organic frameworks (MOFs) have received great attention because of their unusual properties and fascinating structures in separation sciences. However, to the best of our knowledge, there has been no attempt to utilize chiral MOFs as stationary phases in packed‐CEC. Here, a chiral MOF [In3O(obb)3(HCO2)(H2O)]·solvent (4,4′‐oxybisbenzoic acid) was explored as the chiral stationary phase in packed‐CEC for separation of chiral compounds and isomers. The fabricated [In3O(obb)3(HCO2)(H2O)]·solvent packed capillary columns gave fast enantioseparation of (±)‐hydrobenzoin, (±)‐1‐phenyl‐1,2‐ethanediol, and clenbuterol within 3 min in CEC. Besides, the baseline separations of nitrophenol isomers within 6 min were also achieved. The RSDs for the retention time of run‐to‐run, day‐to‐day, and column‐to‐column reproducibility were 1.51–3.63, 1.83–3.98, and 3.42–5.66%, respectively. These results demonstrate that chiral MOFs are promising for enantioseparation in CEC.
High‐speed separation and detection of amino acids in laver using a short capillary electrophoresis system
Authors: Wang Wei , Ma Lihong , Yao Fenzeng , Lin Xiuli , Xu Kaixuan
Published: September 2014

A high‐speed separation method of capillary MEKC with LIF detection had been developed for separation and determination of amino acids in laver. The CE system comprised a manual slotted‐vial array (SVA) for sample introduction that could improve the separation efficiency by reducing injection volume. Using a capillary with 80 mm effective separation length, the separation conditions for amino acids were optimized. Applied with the separation electric field strength of 300 V/cm, the ten amino acids could be completely separated within 2.5 min with 10 mol/L Na2HPO4–NaOH buffer (pH = 11.5) including 30 mmol/L SDS. Theoretical plates for amino acids ranged from 72 000 to 40 000 (corresponding to 1.1–2.0 μm plate heights) and the detection limits were between 25 and 80 nmol/L. Finally, this method was applied to analyze the composition of amino acids in laver and eight known amino acids could be found in the sample. The contents of five amino acids, tyrosine, glutamic acid, glycine, lysine, and aspartic acid that could be completely separated in real sample were determined. The recoveries ranged from 82.3% to 123% that indicated the good reliability for this method in laver sample analysis.
High frequency dielectrophoretic response of microalgae over time
Authors: Hadady Hanieh , Wong Johnson J. , Hiibel Sage R. , Redelman Doug , Geiger Emil J.
Published: September 2014

The high frequency dielectrophoresis (>20 MHz) response of microalgae cells with different lipid content was monitored over time. Chlamydomonas reinhardtii was cultured in regular medium and under nitrogen‐depleted conditions in order to produce populations of cells with low and high lipid content, respectively. The electrical conductivity of the culture media was also monitored over the same time. The upper crossover frequency decreased for high‐lipid cells over time. The single‐shell model predicts that the upper crossover frequency is dictated primarily by the dielectric properties of the cytoplasm. The high frequency DEP response of the high‐lipid cells’ cytoplasm was changed by lipid accumulation. DEP response of the low‐lipid cells also varied with the conductivity of the culture media due to nutrient consumption. Relative lipid content was estimated with BODIPY 505/515 dye by calculating the area‐weighted intensity average of fluorescent images. Finally, microalgae cells were successfully separated based on lipid content at 41 MHz and DEP media conductivity 106 ± 1 μS/cm.
Discovery of potential serum protein biomarkers for lymph node metastasis in oral cancer
Authors: Chai Yang D. , Zhang Lifeng , Yang Yan , Su Trent , Charugundla Prashant , Ai Jiye , Messadi Diana , Wong David T. , Hu Shen
Published: September 2014

Background

The purpose of our study was to identify serum protein biomarkers for node‐positive oral squamous cell carcinoma (OSCC). Biomarkers indicating lymph node metastasis provides a valuable classification methodology to optimize treatment plans for patients with OSCC.

Methods

Quantitative serum proteomic analysis of OSCCs with either node‐positive or node‐negative disease was performed with tandem mass spectrometry and isobaric tagging for relative and absolute quantitation (iTRAQ). Immunoassays were used to validate a panel of candidate protein biomarkers and receiver operating characteristic (ROC) analysis was used to evaluate the performance of the candidate biomarkers.

Results

A total of 282 serum proteins were quantified between node‐positive and node‐negative OSCCs with the proteomic approach. Four candidate biomarkers, gelsolin, fibronectin, angiotensinogen, and haptoglobin, were validated in an independent group of patients with node‐positive or node‐negative OSCC. The best candidate biomarker, gelsolin, yielded a ROC value of 89% for node‐positive OSCC, although the sample size for validation is relatively small. Fibronectin, gelsolin, and angiotensinogen were also found to be differentially expressed between cancer cell lines of node‐positive and node‐negative cancer origin.

Conclusion

Our studies suggest that testing of serum protein biomarkers might help detect lymph node metastasis of oral cancer. Because of limited sample size in our studies, long‐term longitudinal studies with large populations of individuals with oral cancer are needed to validate these potential biomarkers. © 2015 Wiley Periodicals, Inc. Head Neck 38: 118–125, 2016
Chronic trimethyltin chloride exposure and the development of kidney stones in rats
Authors: Ren Xuefeng , Wu Xin , Sui Gang , Gong Zhihong , Yawson Emmanuel , Wu Banghua , Lai Guanchao , Ruan Xiaolin , Gao Hongbin , Zhou Feng , Su Bing , Olson James R. , Tang Xiaojiang
Published: September 2014

We recently reported that occupational exposure to trimethyltin (TMT) is a risk factor for developing kidney stones. To further examine the association between TMT exposure and the formation of kidney stones, we conducted a 180‐day animal study and exposed the randomly grouped Sprague–Dawley (SD) rats to TMT in the drinking water at doses of 0, 8.2, 32.8 and 131.3 µg kg–1 day–1. Transient behavioral changes were observed in the high‐dose group during the first 2 weeks of exposure. TMT exposure led to a significant dose‐dependent inhibition of renal H+/K+‐ATPase and an increase in urinary pH. In comparison to no kidney stones being identified in the control and the lowest dose group, 1 rat in the 32.8 µg kg–1 day–1 dose group and 3 out of 9 rats in the 131.3 µg kg–1 day–1 dose group were found to have stones in the kidney/urinary tract. Pathological analysis showed that more wide spread calcium disposition was observed in kidneys of rats with TMT exposure compared with the rats in the control group. However, X‐ray diffraction (XRD) analysis found that the kidney stones were mainly composed of struvite with the formula: NH4MgPO4 6H2O, while calcium‐containing components were also detected. Together, this study further demonstrates through animal studies that chronic exposure to a relatively low level of TMT induces nephrotoxicity and increases the risk for developing kidney stones. Copyright © 2014 John Wiley & Sons, Ltd.
Human mesenchymal stem cell osteoblast differentiation, ECM deposition, and biomineralization on PAH/PAA polyelectrolyte multilayers
Authors: Pattabhi Sudhakara Rao , Lehaf Ali M. , Schlenoff Joseph B. , Keller Thomas C. S.
Published: September 2014

Polyelectrolyte multilayer (PEMU) coatings built layer by layer with alternating pairs of polyelectrolytes can be tuned to improve cell interactions with surfaces and may be useful as biocompatible coatings to improve fixation between implants and tissues. Here, we show that human mesenchymal stromal cells (hMSCs) induced with bone differentiation medium (BDM) to become osteoblasts biomineralize crosslinked PEMUs built with the polycation poly(allylamine hydrochloride) (PAH) and the polyanion poly(acrylic acid) (PAA). Degrees of hMSC osteoblast differentiation and surface biomineralization on the smooth PAH‐terminated PEMUs (PAH‐PEMUs) and microstructured PAA‐terminated PEMUs (PAA‐PEMUs) reflect differences in cell‐deposited extracellular matrix (ECM). BDM‐induced hMSCs expressed higher levels of the early osteoblast differentiation marker alkaline phosphatase and collagen 1 (COL1) sooner on PAA‐PEMUs than on PAH‐PEMUs. Cells on both types of PEMUs proceeded to express the later stage osteoblast differentiation marker bone sialoprotein (BSP), but the BDM‐induced cells organized a more amorphous Collagen I and denser BSP localization on PAA‐PEMUs than on PAH‐PEMUs. These ECM properties correlated with greater biomineralization on the PAA‐PEMUs than on PAH‐PEMUs. Together, these results confirm the suitability of PAH/PAA PEMUs as a substrate for hMSC osteogenesis and highlight the importance of substrate effects on ECM organization and BSP presentation on biomineralization. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 1818–1827, 2015.
In vitro evaluation of a modified 4‐META/MMA‐TBB resin for filling access holes of screw‐retained implant prostheses
Authors: Tanimura Remy , Suzuki Shiro
Published: September 2014

This study evaluates a modified 4‐META/MMA‐TBB resin (M4M) as a candidate material for filling screw‐retained implant access hole. Its characteristics were compared with a conventional composite resin (CR) with or without a bonding agent (BA) or a ceramic primer (CP). Ceramic blocks were divided into five groups, including (A) CR, (B) CR with BA, (C) CR with CP and BA, (D) M4M, and (E) M4M with CP. Shear bond strengths were measured after 5000 times of thermocycling. Groups A, B, and D were excluded from further tests as they showed no adhesion. A cylindrical cavity (2.5 mm diameter, 3 mm depth) simulating access hole was prepared in a ceramic block and glazed to evaluate micro‐leakage and wear test of groups C and E. The results were statistically analyzed with Mann–Whitney test (p  <  0.05). Shear bond strength of groups C (7.6 ± 2.2 MPa) and E (8.6 ± 1.0 MPa) was not significantly different. In micro‐leakage analysis, average wear depth and wear volume, group E (7.5 ± 3.3%, 59.3 ± 12.9 μm, 0.16 ± 0.04 mm3) showed significantly lower values than those of group C (45.6 ± 24.4%, 76.0 ± 16.4 μm, 0.28 ± 0.03 mm3). It is suggested that the combination of CP and M4M can be one of feasible systems to fill the ceramic access holes of the implant upper structure. © 2014 The Authors. Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 1030–1036, 2015.
Translating textiles to tissue engineering: Creation and evaluation of microporous, biocompatible, degradable scaffolds using industry relevant manufacturing approaches and human adipose derived stem cells
Authors: Haslauer Carla M. , Avery Matthew R. , Pourdeyhimi Behnam , Loboa Elizabeth G.
Published: September 2014

Polymeric scaffolds have emerged as a means of generating three‐dimensional tissues, such as for the treatment of bone injuries and nonunions. In this study, a fibrous scaffold was designed using the biocompatible, degradable polymer poly‐lactic acid in combination with a water dispersible sacrificial polymer, EastONE. Fibers were generated via industry relevant, facile scale‐up melt‐spinning techniques with an islands‐in‐the‐sea geometry. Following removal of EastONE, a highly porous fiber remained possessing 12 longitudinal channels and pores throughout all internal and external fiber walls. Weight loss and surface area characterization confirmed the generation of highly porous fibers as observed via focused ion beam/scanning electron microscopy. Porous fibers were then knit into a three‐dimensional scaffold and seeded with human adipose‐derived stem cells (hASC). Confocal microscopy images confirmed hASC attachment to the fiber walls and proliferation throughout the knit structure. Quantification of cell‐mediated calcium accretion following culture in osteogenic differentiation medium confirmed hASC differentiation throughout the porous constructs. These results suggest incorporation of a sacrificial polymer within islands‐in‐the‐sea fibers generates a highly porous scaffold capable of supporting stem cell viability and differentiation with the potential to generate large three‐dimensional constructs for bone regeneration and/or other tissue engineering applications. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 1050–1058, 2015.
Evaluation of UV–HPLC and mass spectrometry methods for specific activity determination
Authors: Elmore Charles S. , Schenk David J. , Arent Robert , Kingston Lee
Published: September 2014

The specific activity (SA) values determined using two different methods were compared for a set of tritium‐labeled and carbon‐14‐labeled compounds. The methods employed were as follows: (a) liquid chromatography/mass spectrometry (LC/MS) isotopic peak intensity distribution, and (b) determination of the tracer mass concentration using ultraviolet–high‐performance liquid chromatography analysis coupled with the radioactive solution concentration measured by liquid scintillation counting. In general, at lower SA, the accuracy and or precision of the LC/MS‐determined SA value decreased significantly. Because of this decrease in accuracy, a rough guideline of ~10% of the theoretical maximum SA is recommended as the lower cutoff for MS‐based SA measurements. If the tracer contains heteroatoms that possess significant percentages of heavy isotopes at natural abundance (e.g. Cl and Br), then the MS‐based SA cutoff recommendation is approximately 25–30% of the fully labeled compound in the tracer mixture. Additionally, IsoPat2 was found to be the preferred calculation method for LC/MS‐based SA determination because SA values via this program were more consistent with those obtained by ultraviolet concentration calibration with solution count.
Cardiovascular magnetization transfer ratio imaging compared with histology: A postmortem study
Authors: Crooijmans Hendrikus J.A. , Ruder Thomas D. , Zech Wolf‐Dieter , Somaini Sandra , Scheffler Klaus , Thali Michael J. , Bieri Oliver
Published: September 2014

Cardiovascular magnetization transfer ratio (MTR) imaging by steady state free precession is a promising imaging method to assess microstructural changes within the myocardium. Hence, MTR imaging was correlated to histological analysis. Three postmortem cases were selected based on a suspicion of myocardial infarction. MTR and T2‐weighted (T2w) imaging was performed, followed by autopsy and histological analysis. All tissue abnormalities, identified by autopsy or histology, were retrospectively selected on visually matched MTR and T2w images, and corresponding MTR values compared with normal appearing tissue. Regions of elevated MTR (up to approximately 20%, as compared to normal tissue), appearing hypo‐intense in T2w‐images, revealed the presence of fibrous tissue in microscopic histological analysis. Macroscopic observation (autopsy) described scar tissue only in one case. Regions of reduced MTR (up to approximately 20%) corresponded either to (i) the presence of edema, appearing hyperintense in T2w‐images and confirmed by autopsy, or to (ii) inflammatory granulocyte infiltration at a microscopic level, appearing as hypo‐intense T2w‐signal, but not observed by autopsy. Findings from cardiovascular MTR imaging corresponded to histology results. In contrast to T2w‐imaging, MTR imaging discriminated between normal myocardium, scar tissue and regions of acute myocardial infarction in all three cases. J. Magn. Reson. Imaging 2014;40:915–919. © 2013 Wiley Periodicals, Inc.
‘Moringa oleifera: study of phenolics and glucosinolates by mass spectrometry’
Authors: Maldini Mariateresa , Maksoud Salwa A. , Natella Fausta , Montoro Paola , Petretto Giacomo Luigi , Foddai Marzia , De Nicola Gina Rosalinda , Chessa Mario , Pintore Giorgio
Published: September 2014

Moringa oleifera is a medicinal plant and an excellent dietary source of micronutrients (vitamins and minerals) and health‐promoting phytochemicals (phenolic compounds, glucosinolates and isothiocyanates). Glucosinolates and isothiocyanates are known to possess anti‐carcinogenic and antioxidant effects and have attracted great interest from both toxicological and pharmacological points of view, as they are able to induce phase 2 detoxification enzymes and to inhibit phase 1 activation enzymes. Phenolic compounds possess antioxidant properties and may exert a preventative effect in regards to the development of chronic degenerative diseases.

The aim of this work was to assess the profile and the level of bioactive compounds in all parts of M. oleifera seedlings, by using different MS approaches. First, flow injection electrospray ionization mass spectrometry (FI‐ESI‐MS) fingerprinting techniques and chemometrics (PCA) were used to achieve the characterization of the different plant's organs in terms of profile of phenolic compounds and glucosinolates. Second, LC‐MS and LC‐MS/MS qualitative and quantitative methods were used for the identification and/or determination of phenolics and glucosinolates in M. oleifera. Copyright © 2014 John Wiley & Sons, Ltd.
Development, validation and application to real samples of a multiresidue LC‐MS/MS method for determination of β2‐agonists and anabolic steroids in bovine hair
Authors: Leporati M. , Bergoglio M. , Capra P. , Bozzetta E. , Abete M. C. , Vincenti M.
Published: September 2014

β2‐agonists are often abused in cattle breeding because of their effects on animal growth and meat properties. The use of β2‐agonists as growth promoters is forbidden in the European Union (Council Directive 96/23/EC classifies them into group A of Annex I), due to their toxicity and carcinogenic properties, as for anabolic steroids, which are often administered in combination with β2‐agonists, to promote the storage of proteins and increase muscle size.

A unique confirmatory liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method for the quantitative detection of 13 β2‐agonists and anabolic steroids plus the qualitative identification of other three analytes in bovine hair was developed and validated, according to Decision 2002/657/CE. Hair samples were washed with dichloromethane, digested within a NaOH solution and subjected to liquid–liquid extraction. The analysis was performed by high performance liquid chromatography coupled to a triple quadrupole mass spectrometer operating in the selected reaction monitoring mode. The absence of matrix interferents, together with good repeatability of both retention times and relative abundances of diagnostic transitions, allowed the correct identification of all analytes. The quantitative calibrations obtained from spiked blank hair samples proved linear in the range tested. CCα and CCβ ranged from 0.5 ng/g to 30 ng/g. Intralaboratory reproducibility (CV%) ranged between 5.0 and 17.7 and trueness between 96% ± 7% and 105% ± 8%. The applicability of the method to real positive samples was demonstrated for both β2‐agonists and anabolic steroids.

17α‐boldenone was found in most (70%) hair samples obtained from untreated animals, supporting the hypothesis of endogenous production of this steroid. Copyright © 2014 John Wiley & Sons, Ltd.
Transsacral screw safe zone size by sacral segmentation variations
Authors: Lee John J. , Rosenbaum Samuel L. , Martusiewicz Alex , Holcombe Sven A. , Wang Stewart C. , Goulet James A.
Published: September 2014

Variations in sacral segmentation may preclude safe placement of transsacral screws for posterior pelvis fixation. We developed a novel automated 3D technique to determine the safe zone size for transsacral screws in the upper two sacral segments in 526 adult pelvis computed tomography scans. Safe zone sizes were then compared by gender and sacral segmentation variations (number of neuroforamen and the presence/absence of lumbosacral transitional vertebrae, ±LSTV). Ten millimeters was used as the safety threshold for a large screw. 3 (0.6%), 366 (70%), and 157 (30%) sacra had 3, 4, or 5 neuroforamen, respectively. Eighty‐eight (17%) were +LSTV. Safe zone size depended on gender, number of neuroforamen in −LSTV sacra and presence of LSTV (p < 0.001) but not on the uni‐ or bilateral nature of the LSTV. 17% of −LSTV sacra were below the safety threshold in S1, 27% in S2, whereas 3% of +LSTV sacra were below in S1, 74% in S2. Of −LSTV sacra that cannot take an S1 screw safely, 77% can do so in S2, leaving only 4% of sacra that cannot accommodate a screw safely in either upper segment. The results demonstrate a predictable pattern of safe zone size based on gender and sacral segmentation variations. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:277–282, 2015.
A non‐invasive NMR relaxometric characterization of the cyclododecane–solvent system inside porous substrates
Authors: Presciutti F. , Doherty B. , Anselmi C. , Brunetti B. G. , Sgamellotti A. , Miliani C.
Published: September 2014

With the aim of deepening the knowledge on the behavior of cyclododecane (CDD) as a temporary consolidant agent for weathered stones, NMR longitudinal and transverse relaxation decays have been exploited to follow the distribution of cyclododecane solutions into porous matrices. By measuring as function of time the relaxation decay constants of CDD solutions dropped onto porous supports, it has been possible to differentiate the step encompassing the solvent evaporation, which determines the consolidant migration within the matrix, from that governing the consolidant sublimation, which is related to the consolidation effectiveness over time. Copyright © 2014 John Wiley & Sons, Ltd.