bluuebunny/crossref_metadata_2025 huggingface dataset:
Apprendre à l’âge adulte : entre imitation et émancipation
Authors: Vieille-Grosjean Henri , Di Patrizio Gabriel
Published: June 2015

Le processus d’apprentissage en FPC (Formation Professionnelle Continue) s’inscrit dans un espace/temps qui renvoie selon nous à l’agir communicationnel. Il relève d’un espace de sens, référé à la notion de passage et donc de processus. Il est bien connu aujourd’hui qu’une des modalités de l’apprentissage chez les adultes comme chez les enfants, s’appuie sur le mimétisme et l’imitation. D’autre part, le jeu des interactions fait que les apprentissages ne sont pas transmis sans une renégociation autonome et médiate de chacun des sujets « entre soi » et des sujets entre eux (apprentissage vicariant). Cette relation entre les partenaires se fondera sur des caractéristiques qui permettent de comprendre l’interprétation comme une modalité, un médium indispensable à un « apprentissage émancipateur ». Dès lors, le savoir construit, le savoir en élaboration, engage le pas vers une conversion (métanoïa) du regard de l’apprenant adulte, mais également de celui de l’appreneur, vers une autonomisation du sujet et son émancipation.
Les enseignants du secondaire à l’épreuve de la loi de 2005
Authors: Guibert Pascal , Le Corre Nadine
Published: June 2015

En modifiant le code de l’Éducation et la définition du handicap, la loi du 11 février 2005 en faveur des personnes handicapées a permis d’accroître le nombre d’élèves en situation de handicap dans les établissements ordinaires du second degré. Neuf ans après la promulgation de cette loi, la confrontation sur le terrain avec des élèves à « besoins éducatifs particuliers » est une épreuve que les enseignants peuvent évoquer en tant qu’expérience. Quel est l’impact de cette loi sur les pratiques professionnelles des enseignants du second degré? Dans une perspective interactionniste, cet article tente de montrer de quelles manières la loi de 2005 met en question le « mandat » et « la licence » (Hughes, 1996) de la profession enseignante, mais aussi selon quelles modalités elle peut encourager les enseignants du second degré à développer de nouvelles compétences professionnelles.
L’activité de démoustication, entre contraintes techniques, écologiques et sociales
Authors: Pécaud Sophie
Published: June 2015

Nous présentons les résultats d’une étude de terrain menée en 2009 et visant à une meilleure compréhension de l’activité des agents de démoustication de l’EID Atlantique dans les zones humides littorales de la façade atlantique française (du Morbihan à la Gironde). Nous nous attachons d’abord à caractériser le contexte dans lequel ces agents travaillent, tant en termes écologiques qu’en termes sociaux. Puis nous proposons une modélisation de leur activité, mettant en lumière de manière inédite sa forte composante sociale : il s’agit pour eux de maintenir, dans les zones qu’ils prennent en charge, non seulement un équilibre écologique minimisant la prolifération de moustiques, mais aussi un équilibre social visant la satisfaction de l’ensemble des usagers auxquels ils ont affaire (paludiers, ostréiculteurs, éleveurs de bétail, membres d’associations de chasse et d’associations naturalistes, randonneurs et promeneurs).
A new species of Cochlospermum (Bixaceae) from Arnhem Land, Northern Territory, Australia
Authors: Cowie Ian Donald , Kerrigan Raelee A.
Published: June 2015

A new species of small tree, Cochlospermum arafuricum Cowie & Kerrigan sp. nov. from the wet-dry tropics of Australia is described and illustrated here. The species is distinctive in having the leaves divided for ⅓–½ of their length with broadly triangular, aristate leaf lobes, conspicuously serrate margins, red outer staminal filaments and with most parts almost glabrous. It appears to be relatively common although not abundant and occurs in various woodland communities in foot slope situations over a wide area of central and eastern Arnhem Land. As there are no obvious threats or decline and the species is relatively widespread and common, it is assessed as Least Concern using IUCN criteria. A key to species of Cochlospermum in the Northern Territory is provided.
Source, transport, and evolution of saline groundwater in a shallow Holocene aquifer on the tidal deltaplain of southwest Bangladesh
Authors: Worland Scott C. , Hornberger George M. , Goodbred Steven L.
Published: June 2015

Deltaic groundwater resources are often vulnerable to degradation from seawater intrusion or through interaction with saline paleowaters. The Ganges‐Brahmaputra‐Meghna River delta, in Bangladesh and West Bengal, India, is a particularly vulnerable area with an estimated 20 million coastal inhabitants directly affected by saline drinking water. The shallow groundwater of the coastal regions is primarily brackish with pockets of fresher water. A small‐scale hydrologic investigation of groundwater salinity beneath an embanked tidal channel island was undertaken to explore possible hydrogeological explanations of the distribution of water salinities in the shallow aquifer. This study employs a combination of 3H and 14C dating, electromagnetic subsurface mapping, and a 2‐D solute transport model. The authors conclude that the shallow groundwater salinity can best be explained by the slow infiltration of meteoric water into paleo‐brackish estuarine water that was deposited during the early‐mid Holocene.
Feasibility study on the derivation of the O+‐O collision frequency from ionospheric field‐aligned observations
Authors: Dang Tong , Lei Jiuhou , Dou Xiankang , Wan Weixing
Published: June 2015

Recently, Vickers et al. (2013) used a simplified ion momentum equation to derive the ion‐neutral (O+‐O) collision frequency and thermospheric atomic oxygen density from the European Incoherent Scatter Svalbard Radar data. It was assumed that the vertical neutral wind at high latitudes is generally small under geomagnetically quiet conditions so that it was neglected in their derivation. Although the vertical neutral wind may indeed be small, the field‐aligned neutral wind component, which needs to be taken into consideration in the ion momentum equation, can be large. Simulations with the Thermosphere‐Ionosphere Electrodynamics Global Circulation Model have been carried out to evaluate the effect of the neutral wind on the estimation of the ion‐neutral collision frequency from the ion momentum equation. Our results reveal that, even at high latitudes, the effect of the neutral wind can be significant in the derivation of the ion‐neutral collision frequency from ionospheric field‐aligned observations, especially at night.
A statistical study of the low‐altitude ionospheric magnetic fields over the north pole of Venus
Authors: Zhang T. L. , Baumjohann W. , Russell C. T. , Villarreal M. N. , Luhmann J. G. , Teh W. L.
Published: June 2015

Examination of Venus Express (VEX) low‐altitude ionospheric magnetic field measurements during solar minimum has revealed the presence of strong magnetic fields at low altitudes over the north pole of Venus. A total of 77 events with strong magnetic fields as VEX crossed the northern polar region were identified between July 2008 and October 2009. These events all have strong horizontal fields, slowly varying with position. Using the superposed epoch method, we find that the averaged peak field is about 45 nT, which is well above the average ambient ionospheric field of 20 nT, with a full width at half maximum duration of 32 s, equivalent to a width of about 300 km. Considering the field orientation preference and spacecraft trajectory geometry, we conclude that these strong fields are found over the northern hemisphere with an occurrence frequency of more than 33% during solar minimum. They do not show a preference for any particular interplanetary magnetic field (IMF) orientation. However, they are found over the geographic pole more often when the interplanetary field is in the Venus orbital plane than when it is perpendicular to the orbital plane of Venus. The structures were found most frequently in the −E hemisphere, determined from the IMF orientation. The enhanced magnetic field is mainly quasi perpendicular to solar wind flow direction, and it is suggested that these structures form in the low‐altitude collisional ionosphere where the diffusion and convection times are long.
Intraseasonal to seasonal variability of the intermediate waters along the Kuroshio path east of Taiwan
Authors: Mensah Vigan , Jan Sen , Chang Ming‐Huei , Yang Yiing‐Jang
Published: June 2015

The variability of the intermediate water (IW) east of Luzon and Taiwan is investigated using data acquired from moored instrumented lines and shipboard hydrographic and current velocity surveys. The IW is defined as the water mass with a local salinity minimum along the Kuroshio path. An empirical formula is developed to estimate the IW salinity minimum east of Taiwan using temperature measurements around 580 m depth. Properties of the IW east of Taiwan vary greatly as a result of variable contributions from three water masses including the high‐salinity South China Sea Intermediate Water (SCSIW), the low‐salinity North Pacific Intermediate Water (NPIW), and the intermediate‐salinity Kuroshio Intermediate Water (KIW). Our analysis concludes that NPIW is predominantly found east of Taiwan, and the northward transport of KIW from northeast of Luzon to east of Taiwan is not a steady process. Concurrent mooring measurements at these two locations enable us to correlate the variations of the layer thickness of the Kuroshio near its origin (KLTo) northeast of Luzon to the nature of the IW east of Taiwan. When the Kuroshio is deep, i.e., large KLTo, KIW is transported northward across the Luzon Strait, where its salinity increases presumably due to turbulence mixing with SCSIW. This modified KIW is then transported to the east of Taiwan. When the Kuroshio is shallow, i.e., small KLTo, the KIW transport east of Luzon is nil or southward. East of Taiwan, NPIW feeds in below the Kuroshio and is transported northward beyond the I‐Lan Ridge.
The Fluid Joint: The Soft Spot of Micro‐ and Nanosystems
Authors: Mastrangeli Massimo
Published: June 2015

Fluid bridges are ubiquitous soft structures of finite size that conform to and link the surfaces of neighboring objects. Fluid joints, the specific type of fluid bridge with at least one extremity constrained laterally, display even more pronounced reactivity and self‐restoration, which make them remarkably suited for assembly, actuation, and manipulation purposes. Their peculiar surface and bulk properties place fluid joints at the rich intersection of diverse scientific interests, and foster their widespread use throughout micro‐ and nanotechnology. A critical survey of the mechanics and of the manifold applications of fluid bridges and joints in micro‐ and nanosystems is presented here, along with current challenges and multidisciplinary perspectives.
Seasonal Variation in the Price Discovery Process of International Wheat
Authors: Arnade Carlos , Vocke Gary
Published: June 2015

This paper uses the Gonzalo–Granger price discovery method to determine whether wheat prices are primarily discovered in the Northern Hemisphere or Southern Hemisphere and whether the price discovery process changes throughout the calendar year. Testing U.S. hard red winter prices against Argentina's wheat price we find that the United States dominates the price discovery process 7 months of the year. Testing U.S Portland soft white prices against Australia's wheat price we find that both countries play a significant role in price discovery but the relative country contribution to price formation varies throughout the year. We also find that the price discovery process changes over time. [EconLit citations: D4, C1, F15].
Cognitive function in chronic rhinosinusitis: a controlled clinical study
Authors: Soler Zachary M. , Eckert Mark A. , Storck Kristina , Schlosser Rodney J.
Published: June 2015

Background

Cognitive dysfunction in patients with chronic rhinosinusitis (CRS) has previously received little attention. Cognitive data generally includes only subjective measures and lack appropriate controls when cognition is considered. The purpose of this study was to characterize dimensions of cognitive function that are affected in patients with CRS compared to a control sample using subjective and objective measures of cognitive function.

Methods

Patients fulfilling diagnostic criteria for CRS and non‐CRS controls were recruited from the same clinical reference population. Patient‐reported cognitive dysfunction was assessed using the Cognitive Failures Questionnaire (CFQ) and fatigue via the Fatigue Severity Scale (FSS). Objective cognitive function was assessed using a battery of tests from the Automated Neuropsychological Assessment Metrics (ANAM) computerized platform.

Results

A total of 100 subjects were enrolled, including 50 patients with active CRS and 50 control subjects. Patients with CRS scored significantly worse in subjective cognition as measured by total CFQ scores (38.3 ± 16.5 vs 30.9 ± 12.5; p = 0.009) and the FSS (4.2 ± 1.6 vs 3.0 ± 1.5; p = 0.001). Patients with CRS were also found to have worse simple reaction time scores compared to controls without CRS (162.4 ± 56.2 vs 193.0 ± 44.6; p = 0.003). These differences persisted regardless of polyp status. Performance differences for FSS and SRT measures remained significant after controlling for age, gender, race/ethnicity, education, allergic rhinitis, asthma, obstructive sleep apnea, depression, and antihistamine usage.

Conclusion

Patients with CRS report significantly more cognitive dysfunction and fatigue on validated instruments and had worse reaction times on computerized testing. Further study is necessary to determine whether available treatments impact these measures.
Analysis of the clinical backgrounds of patients who developed respiratory acidosis under high‐flow oxygen therapy during emergency transport
Authors: Ogino Hirokazu , Nishimura Naoki , Yamano Yasuhiko , Ishikawa Genta , Tomishima Yutaka , Jinta Torahiko , Takahashi Osamu , Chohnabayashi Naohiko
Published: June 2015

Aim

High‐flow oxygen is often administered to patients during emergency transport and can sometimes cause respiratory acidosis with disturbed consciousness, thereby necessitating mechanical ventilation. Although oxygen titration in chronic obstructive pulmonary disease patients during emergency transport reduces mortality rates, the clinical risk factors for respiratory acidosis in emergency settings are not fully understood. Therefore, we analyzed the clinical backgrounds of patients who developed respiratory acidosis during pre‐hospital transport.

Methods

This was a retrospective study of patients who arrived at our hospital by emergency transport in 2010 who received high‐flow oxygen while in transit. Respiratory acidosis was defined by the following arterial blood gas readings: pH, ≤7.35; PaCO2, ≥45 mmHg; and HCO3−, ≥24 mmol/L. The risk factors were identified using multivariable logistic regression analysis.

Results

In 765 study patients, 66 patients showed respiratory acidosis. The following risk factors for respiratory acidosis were identified: age, ≥65 years (odds ratio [OR] 1.4; 95% confidence interval [CI], 0.7–2.8); transportation time, ≥10 min (OR 2.0; 95% CI, 1.1–3.7); three digits on the Japan Coma Scale (OR 3.1; 95% CI, 1.7–5.8); percutaneous oxygen saturation, ≤90% (OR 1.6; 95% CI, 0.8–3.0); tuberculosis (OR 4.5; 95% CI, 1.4–15.1); asthma (OR 1.8; 95% CI, 0.6–5.3); pneumonia (OR 1.5; 95% CI, 0.7–3.1); and lung cancer (OR 3.9; 95% CI, 1.5–10.1). These underlying diseases as risk factors included both comorbid diseases and past medical conditions.

Conclusions

The factors identified may contribute to the development of respiratory acidosis. Further studies on preventing respiratory acidosis will improve the quality of emergency medical care.
Quantum efficiencies in finite disordered networks connected by many‐body interactions
Authors: Ortega Adrian , Vyas Manan , Benet Luis
Published: June 2015

The quantum efficiency in the transfer of an initial excitation in disordered finite networks, modeled by the k‐body embedded Gaussian ensembles of random matrices, is studied for bosons and fermions. The influence of the presence or absence of time‐reversal symmetry and centrosymmetry/centrohermiticity are addressed. For bosons and fermions, the best efficiencies of the realizations of the ensemble are dramatically enhanced when centrosymmetry (centrohermiticity) is imposed. For few bosons distributed in two single‐particle levels this permits perfect state transfer for almost all realizations when one‐particle interactions are considered. For fermionic systems the enhancement is found to be maximal for cases when all but one single particle levels are occupied.

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Bottom‐Up Construction of Mesoporous Nanotubes from 78‐Component Self‐Assembled Nanobarrels
Authors: Zhang Guang‐Lu , Zhou Li‐Peng , Yuan Da‐Qiang , Sun Qing‐Fu
Published: June 2015

Segmental and continuous hexagonal‐packed mesoporous metal–organic nanotubes (MMONTs) with outside diameters of up to 4.5 nm and channel sizes of 2.4 nm were hierarchically constructed by a rational multicomponent self‐assembly process involving starting from [L2Pd2(NO3)2] (L=o‐phenanthroline or 2,2′‐bipyridine) and 4‐pyridinyl‐3‐pyrazole. An unprecedented crystallization‐driven cross‐linking between discrete nanobarrel building units by spontaneous loss of the capping ligands to form infinite nanotubes was observed. Such a barrel‐to‐tube transformation provides new possibilities for the fabrication of MMONTs using the solution bottom‐up approach.
Preparation and characterization of mPEG‐g‐α‐zein biohybrid micelles as a nano‐carrier
Authors: Song Rongguang , Zhou Yihan , Li Yanchun , Yang Zechuan , Li Fan , Huang Qingrong , Shi Tongfei , Zhang Guo
Published: June 2015

A new kind of block copolymer micelles methoxy polyethylene glycol (mPEG) grafted α‐zein protein (mPEG‐g‐α‐zein) was synthesized. The chemical composition of mPEG‐g‐α‐zein was identified with the help of FT‐IR and 1H‐NMR. The biohybrid polymer can self‐assemble into spherical core–shell nanoparticles in aqueous solution. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to investigate the self‐assembled morphology of mPEG‐g‐α‐zein. Dynamic light scattering (DLS) results showed that the particle size of mPEG‐g‐α‐zein was about 90 nm. Moreover, the nanoparticles had a very low critical micelle concentration value with only 0.02 mg/mL. Then, the anticancer drug curcumin (CUR) was encapsulated into the biohybrid polymer micelles. The in vitro drug release profile showed a zero‐order release of CUR up to 12 h at 37°C. Cell viability studies revealed that the mPEG‐g‐α‐zein polymer exhibited low cytotoxicity for HepG2 cells (human hepatoma cells). Consequently, the mPEG‐g‐α‐zein micelles can be used as a potential nano‐carrier to encapsulate hydrophobic drugs and nutrients. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42555.
Qualitative analysis of chemical constituents in traditional Chinese medicine analogous formula cheng‐Qi decoctions by liquid chromatography–mass spectrometry
Authors: Wen Xuexun , Luo Kedi , Xiao Shun , Ai Ni , Wang Shufang , Fan Xiaohui
Published: June 2015

Cheng‐Qi decoctions (CQs), a group of analogous formulas, are well‐known traditional Chinese preparations used as purgative remedies to treat ‘internal heat’‐induced symptoms, which manifest as a bloated and painful abdomen, hard stools, fever and other clinical observations. In this study, HPLC‐ESI‐MS/MS and UPLC‐TOF‐MS were employed for separation and structural identification of constituents in CQs. As a result, a total of 90 compounds, including seven anthraquinones, 39 flavones, 21 glycosides, 11 stilbene glycosides, six organic acids, five coumarins and one lignans, were detected and tentatively identified in CQs extracts. The characterization results shed some light on the scientific foundation for clinical application of the CQ analogous formulas. Our results also indicate that the HPLC‐MS method is useful for the systemic identification of major constituents in traditional Chinese medicine formulas. Copyright © 2015 John Wiley & Sons, Ltd.
“Hummingbird” Behaviour of N‐Heterocyclic Carbenes Stabilises Out‐of‐Plane Bonding of AuCl and CuCl Units
Authors: Teci Matthieu , Brenner Eric , Matt Dominique , Gourlaouen Christophe , Toupet Loic
Published: June 2015

An N‐heterocyclic carbene substituted by two expanded 9‐ethyl‐9‐fluorenyl groups was shown to bind an AuCl unit in an unusual manner, namely with the AuX rod sitting out of the plane defined by the heterocyclic carbene unit. As shown by X‐ray studies and DFT calculations, the observed large pitch angle (21°) arises from an easy displacement of the gold(I) atom away from the carbene lone‐pair axis, combined with the stabilisation provided by weak CH⋅⋅⋅Au interactions involving aliphatic and aromatic H atoms of the NHC wingtips. Weak, intermolecular Cl⋅⋅⋅H bonds are likely to cooperate with the H⋅⋅⋅Au interactions to stabilise the out‐of‐plane conformation. A general belief until now was that tilt angles in NHC complexes arise mainly from steric effects within the first coordination sphere.
Influence of Fluorination on the Conformational Properties and Hydrogen‐Bond Acidity of Benzyl Alcohol Derivatives
Authors: Bogdan Elena , Compain Guillaume , Mtashobya Lewis , Le Questel Jean‐Yves , Besseau François , Galland Nicolas , Linclau Bruno , Graton Jérôme
Published: June 2015

The effect of fluorination on the conformational and hydrogen‐bond (HB)‐donating properties of a series of benzyl alcohols has been investigated experimentally by IR spectroscopy and theoretically with quantum chemical methods (ab initio (MP2) and DFT (MPWB1K)). It was found that o‐fluorination generally resulted in an increase in the HB acidity of the hydroxyl group, whereas a decrease was observed upon o,o′‐difluorination. Computational analysis showed that the conformational landscapes of the title compounds are strongly influenced by the presence of o‐fluorine atoms. Intramolecular interaction descriptors based on AIM, NCI and NBO analyses reveal that, in addition to an intramolecular OH⋅⋅⋅F interaction, secondary CH⋅⋅⋅F and/or CH⋅⋅⋅O interactions also occur, contributing to the stabilisation of the various conformations, and influencing the overall HB properties of the alcohol group. The benzyl alcohol HB‐donating capacity trends are properly described by an electrostatic potential based descriptor calculated at the MPWB1K/6‐31+G(d,p) level of theory, provided solvation effects are taken into account for these flexible HB donors.
1,2,4‐Triazole Links and N‐Azo Bridges Yield Energetic Compounds
Authors: Tang Yongxing , Gao Haixiang , Parrish Damon A. , Shreeve Jean'ne M.
Published: June 2015

Triazole links and polynitropyrazole rings give rise to compounds with energetic properties. These materials were fully characterized by NMR and infrared spectroscopy, elemental analysis, and differential scanning calorimetry (DSC). In addition, the structures of compounds 5 and 8 were confirmed by single‐crystal X‐ray diffraction analysis. Detonation properties, calculated from heats of formation and experimental densities, thermal stabilities, and impact and friction sensitivities support the potential use of these materials for explosive applications.
Palladium‐Catalyzed C(sp3)H Arylation of N‐Boc Benzylalkylamines via a Deprotonative Cross‐Coupling Process
Authors: Hussain Nusrah , Kim Byeong‐Seon , Walsh Patrick J.
Published: June 2015

Diarylmethylamines are key intermediates and products in the pharmaceutical industry. Herein we disclose a novel method toward the synthesis of these important compounds via CH functionalization. Presented is a reversible deprotonation of N‐Boc benzylalkylamines at the benzylic CH with in situ arylation by a NiXantPhos‐based palladium catalyst (50–93 % yield, 29 examples). The method is also successful with N‐Boc‐tetrahydroisoquinolines. The advantages of this method are it avoids strong bases, low temperatures, and the need to transmetallate to main group metals for the coupling.
Modeling of unbalanced three‐phase driving‐point impedance with application to control of grid‐connected power converters
Authors: Li Zhen , Wong Siu‐Chung , Tse Chi K. , Liu Xiangdong
Published: June 2015

The dq transformation is widely used in the analysis and control of three‐phase symmetrical and balanced systems. The transformation is the real counterpart of the complex transformations derived from the symmetrical component theory. The widespread distributed generation and dynamically connected unbalanced loads in a three‐phase system inherently create unbalanced voltages to the point of common coupling. The unbalanced voltages will always be transformed as coupled positive‐sequence and negative‐sequence components with double‐frequency ripples that can be removed by some filtering algorithms in the dq frame. However, a technique for modeling unbalanced three‐phase impedance between voltages and currents of same sequences or of opposite sequences is still missing. We propose an effective method for modeling unbalanced three‐phase impedance using a decoupled zero‐sequence impedance and two interacting positive‐sequence and negative‐sequence balanced impedances in the dq frame. The proposed method can decompose a system with unbalanced resistance, inductance, or capacitance into a combination of independent reciprocal bases (IRB). Each IRB basis belongs to one of the positive‐sequence, negative‐sequence, or zero‐sequence system components to facilitate further analysis. The effectiveness of this approach is verified with a case study of an unbalanced load and another case study of an unbalanced voltage compensator in a microgrid application. Copyright © 2015 John Wiley & Sons, Ltd.
Diatoms as a tracer of hydrological connectivity: are they supply limited?
Authors: Coles Anna E. , Wetzel Carlos E. , Martínez‐Carreras Núria , Ector Luc , McDonnell Jeffrey J. , Frentress Jay , Klaus Julian , Hoffmann Lucien , Pfister Laurent
Published: June 2015

Recent work has shown that aerial diatoms are a useful ecological tracer of hydrological connectivity in the hillslope–riparian zone–stream (HRS) system. While such work has improved both our understanding of catchment functioning and aerial diatom taxonomy, assemblages and distribution, further work is hampered by lack of data on diatom population depletion during rainfall events. We still do not know whether or not diatom tracers are supply limited. Here we test the null hypothesis that aerial diatoms exhibit infinite supply in the context of natural rainfall events. Rainfall simulation experiments were conducted in a small forested catchment in northwest Luxembourg. We extracted periodically soil surface samples and overland flow samples for diatom population size and species assemblage analyses. Diatom population size was quantified using a new approach we have developed, which involves extracting diatoms using carbonated water and an isopycnic separation technique. Our results showed that pre‐event population size was c. 96 100 diatoms per cm2 in the riparian zone. During the artificial rainfall event, the diatom population was depleted by 72% to 27 200 diatoms per cm2. The diatom assemblage was characteristic of a frequently disturbed environment. Overall, these results suggest that diatoms are supply limited, and are flushed significantly throughout rainfall events. Nevertheless, based on the data from these 1 in 10‐year rainstorm simulations, the riparian zone diatom population is unlikely to be exhausted on an event time scale. Further research is now underway to investigate the spatial and temporal variability of aerial diatom communities across a range of storm sizes. Copyright © 2015 John Wiley & Sons, Ltd.
Redox‐State Dependent Ligand Exchange in Manganese‐Based Oxidation Catalysis
Authors: Abdolahzadeh Shaghayegh , de Boer Johannes W. , Browne Wesley R.
Published: June 2015

Manganese‐based oxidation catalysis plays a central role both in nature, in the oxidation of water in photosystem II (PSII) and the control of reactive oxygen species, as well as in chemical processes, in the oxidation of organic substrates and bleaching applications. The focus of this review is on efforts made to explore and elucidate the redox‐dependent coordination chemistry of these manganese‐based systems in solution and the mechanisms by which their catalytic redox reactions proceed. We also examine the behaviour and activity of complexes that have been developed and used as models for the active sites of the corresponding enzymes, or used as catalysts in the oxidation of organic substrates. Given the current concern over the environmental and economic impact of chemical processes, manganese catalysts that use H2O2as oxidant are the primary focus of this review.
Synthesis and Characterisation of Various Diester and Triester Adducts of TiCl4
Authors: Blackburn Ben J. , Crane Jared H. , Knapp Caroline E. , Marchand Peter , Pugh David , Parkin Ivan P. , Carmalt Claire J.
Published: June 2015

Titanium(IV) chloride and the triester glycerol tribenzoate (gtb) were reacted under moisture‐free conditions in order to investigate the use of triester‐containing oils in the purification of TiCl4 in industrial processes. This resulted in the isolation of a chloro‐bridged dimeric complex containing four titanium centres [{(TiCl4)2(gtb)}2] (1). Further novel coordination compounds of TiCl4 and the diesters; diisopropyl malonate, dibenzyl malonate and diethyl succinate were synthesised by direct reaction under moisture‐free conditions, yielding [TiCl4{CH2(COOiPr)2}] (2), [TiCl4{CH2(COOCH2Ph)2}] (3) and [TiCl4{C2H4(COOEt)2}] (4) respectively. The structures of compounds 1–4 were determined by single‐crystal X‐ray diffraction. All structures assumed an octahedral geometry consisting of the titanium bound to four chloride ligands and the diester molecule acting as a bidentate ligand, through its two carbonyl oxygen atoms. Exposure of the isopropyl malonate reaction to trace amounts of water during synthesis resulted in the formation of an oxo‐bridged dimeric structure [Ti2(μ‐O)Cl3{CH2(COOiPr)2}2] (2b), the structure of which was also obtained via single‐crystal X‐ray diffraction.
Production of lipid from depolymerised lignocellulose using the biocontrol yeast, Rhodotorula minuta: The fatty acid profile remains stable irrespective of environmental conditions
Authors: Sargeant Lisa A. , Mardell Matthew , Saad‐Allah Khalil M. , Hussein Ali H. , Whiffin Fraeya , Santomauro Fabio , Chuck Christopher J.
Published: June 2015

The oleaginous yeast Rhodotorula minuta has been used previously as a biocide agent and for the production of β‐carotene. In addition, R. minuta has been shown to produce up to 40% lipids, while demonstrating a faster growth rate than the similar oleaginous yeasts; Lipomyces starkeyii and R. glutinis. In this study, this promising yeast was evaluated for its potential to produce glyceride lipids under the harsh conditions and complex sugar mixtures produced from depolymerised lignocellulose. The fatty acid profile of R. minuta was not found to change significantly irrespective of the environmental conditions and contained approximately 20% palmitic acid, 5% stearic acid, 60% oleic acid and 15% linolenic acid. R. minuta was found to grow on a range of sugars, and could consume xylose and glucose when both sugars were present; however, R. minuta was found to be highly sensitive to inhibitors, such as furfurals and organic acids, formed under the harsh lignocellulose depolymerisation conditions. Accordingly R. minuta did not grow well on biomass depolymerised with an acid pre‐treatment stage. However, R. minuta was cultured successfully on food waste depolymerised with no additional acids, producing up to 19 g/l cell mass with a lipid content of up to 25% of the dry cell weight.

Practical applications: While high oil productivity, fast growth rates and a suitable fatty acid composition are key traits for the economic viability of SCO production, it is essential that the organism can be cultured and produce lipids from low‐cost substrates. This requires the ability to assimilate the nutrients present in the desired hydrolysate, as well as maintain high‐growth rates in the presence of inhibitory compounds produced during the hydrolysis process. In this paper, we demonstrate that the yeast R. minuta has industrial applicability in being able to convert depolymerised waste food to lipids with a profile akin to rapeseed oil.

Rhodotorula minuta lipid cultured on depolymerised food waste.
Ureido‐Pyridazinone Derivatives: Insights into the Structural and Conformational Properties for STAT3 Inhibition
Authors: Meneghetti Fiorella , Villa Stefania , Masciocchi Daniela , Barlocco Daniela , Toma Lucio , Han Dong‐Cho , Kwon Byoung‐Mog , Ogo Naohisa , Asai Akira , Legnani Laura , Gelain Arianna
Published: June 2015

Three new ureido‐pyridazinone derivatives, which are structurally related to the known STAT3 inhibitor AVS‐0288, were designed by taking into account the structure–activity relationships determined for several ureido‐oxadiazole derivatives previously studied by our group. Their synthesis was first attempted through suitable 5‐aminopyridazinone intermediates (6a and 6b), which molecular structures were confirmed by means of X‐ray diffraction data on 6a. Amine functionalization was unsuccessful, therefore, an alternative method was devised. Dual‐luciferase and AlphaScreen‐based assays were used to test their activity. The obtained data were rationalized on the basis of a modeling study, which focused our attention on the geometrical preferences of the ureido moiety. Computational results seem to indicate that both the 1,2,5‐oxadiazole ring and the extended ZZ arrangement are essential and probably act in a synergistic way to confer significant activity against STAT3.
A Non‐Enzymatic Glucose Sensor Based on Ni/MnO2 Nanocomposite Modified Glassy Carbon Electrode
Authors: Wang Yan , Bai Wushuang , Nie Fei , Zheng Jianbin
Published: June 2015

A novel flower like 3D nickel/manganese dioxide (Ni/MnO2) nanocomposite was synthesized by a kind of simple electrochemical method and the formation mechanism of flower like structure was also researched. In addition, morphology and composition of the nanocomposite were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), and X‐ray photoelectron spectroscopy (XPS). Then the Ni/MnO2 nanocomposites were applied to fabricate electrochemical non‐enzymatic glucose sensor. The electrochemical investigation for the sensor indicated that it possessed an excellent electrocatalytic property for glucose, and could applied to the quantification of glucose with a linear range from 2.5×10−7 to 3.5×10−3 M, a sensitivity of 1.04 mA mM−1 cm−2, and a detection limit of 1×10−7 M (S/N=3). The proposed sensor also presented attractive features such as interference‐free, and long‐term stability. The present study provided a general platform for the one‐step synthesis of nanomaterials with novel structure and can be extended to other optical, electronic and magnetic nanocompounds.
Biosensing Applications of V2O5‐CeO2 Mesoporous Silica
Authors: Luo Xi , Shu Hao , Wan Qijin , Wang Zhaohao , Yang Nianjun
Published: June 2015

Mesoporous silica has been functionalized with vanadium pentoxide (V2O5) and cerium oxide (CeO2). It was then immobilized with biocatalyst horseradish (HRP) to realize highly sensitive detection of H2O2. The electrode was characterized with SEM, cyclic voltammetry, and impedance measurements. A well‐defined peak for HRP reduction was noticed at about −0.31 V with an apparent heterogeneous electron transfer rate constant of 1.01 s−1. The catalytic reduction of H2O2 was achieved. The Michaelis constant was calculated to be 0.018 mM. On this electrode, H2O2 was detectable in the range of 20 to 180 µM and the detection limit was 3.0 µM.
Selective and Sensitive Determination of Uranyl Ions in Complex Matrices by Ion Imprinted Polymers‐Based Electrochemical Sensor
Authors: Kalate Bojdi Majid , Behbahani Mohammad , Najafi Mostafa , Bagheri Akbar , Omidi Fariborz , Salimi Sara
Published: June 2015

We report on the design of a UO22+‐selective electrode based on the use of UO22+ imprinted polymer nanoparticles (IP‐NPs), and its application for the differential pulse adsorptive cathodic stripping voltammetry determination of uranyl ions. A carbon paste electrode was modified with the IP‐NPs, and differential pulse adsorptive cathodic stripping voltammetry was applied as the detection technique after open‐circuit sorption of UO22+ ions. The modified electrode responses to UO22+ was linear in the 0.1 µg L−1 to 10 µg L−1 and in the 0.01 mg L−1 to 10 mg L−1. The method detection limit of the sensor was 0.03 µg L−1.
Rill length and plot‐scale effects on the hydrogeomorphologic response of gravelly roadbeds
Authors: Thomaz Edivaldo L. , Ramos‐Scharrón Carlos E.
Published: June 2015

Although unpaved roads are well‐recognized as important sources of Hortonian overland flow and sediment in forested areas, their role in agriculturally‐active rural settings still lacks adequate documentation. In this study, we assessed the effect of micro‐catchment size, slope, and ground cover on runoff and sediment generation from graveled roadbeds servicing a rural area in southern Brazil. Fifteen replications based on 30‐min‐long simulated rainfall experiments were performed at constant rainfall intensities of 22–58 mm h−1 on roadbeds with varying characteristics including ~3–7 m2 micro‐catchment areas, 2–11° slopes, 2–9.7‐m‐long shallow rill features, and 30–100% gravel cover. The contributions of micro‐catchment size and rill length were the most important physical characteristics affecting runoff response and sediment production; both the size of the micro‐catchment and the length of the rills were inversely related to sediment loss and this contradicts most of the rill erosion literature. The effect of micro‐catchment size on runoff and sediment response suggests a potentially problematic spatial‐scale subjectivity of experimental plot results. The inverse relationship between rill length and sediment generation is interpreted here as related to the predominance of coarse fragments within rills, the inability of the shallow flows generated during the simulations to erode this sediment, and their role as zones of net sediment storage. Copyright © 2015 John Wiley & Sons, Ltd.
Spatial variation in soil resistance to flowing water erosion along a regional transect in the Loess Plateau
Authors: Geng Ren , Zhang Guang‐hui , Li Zhen‐Wei , Wang Hao
Published: June 2015

The factors influencing soil erosion may vary with scale. It remains unclear whether the spatial variation in soil erosion resistance is controlled by regional variables (e.g. precipitation, temperature, and vegetation zone) or by local specific variables (e.g. soil properties, root traits, land use, and farming operations) when the study area enlarges from a hillslope or catchment to the regional scale. This study was performed to quantify the spatial variations in soil erosion resistance to flowing water under three typical land uses along a regional transect on the Loess Plateau and to identify whether regional or local specific variables are responsible for these changes. The results indicated that the measured soil detachment capacities (Dc) of cropland exhibited an irregular trend along the regional transect. The Dc of grassland increased with mean annual precipitation, except for two sites (Yijun and Erdos). The measured Dc of woodland displayed an inverted ‘U’ shape. The changes in rill erodibility (Kr) of three land uses were similar to Dc, whereas no distinguishable trend was found for critical shear stress (τc). No significant correlation was detected between Dc, Kr and τc, and the regional variables. The spatial variation in soil erosion resistance could be explained reasonably by changes in soil properties, root traits, land use, and farming operations, rather than regional variables. The adjustment coefficient of Kr for grassland and woodland could be well simulated by soil cohesion and root mass density (R2 = 0.70, P < 0.01), and the adjustment coefficient of critical shear stress could be estimated with aggregate stability (R2 = 0.57, P < 0.01). The results are helpful for quantifying the spatial variation in soil detachment processes by overland flow and to develop process‐based erosion model at a regional scale. Copyright © 2015 John Wiley & Sons, Ltd.
Im Sog der Großen
Authors: Grube Nikolai , Delvendahl Kai
Published: June 2015

Maya‐Stadt im Regenwald: Als das kleine Königtum Uxul unter die Oberherrschaft der mächtigen Kaan‐Dynastie geriet, begann ein Aufstieg, dem später der gemeinsame Niedergang folgte. Neue Zeugnisse dieser politischen Macht‐ und Siedlungsgeschichte ergräbt nun ein deutsch‐mexikanisches Archäologenteam.
Cost‐effectiveness of strategies for testing current hepatitis C virus infection
Authors: Chapko Michael K. , Dufour D.Robert , Hatia Rikita I. , Drobeniuc Jan , Ward John W. , Teo Chong‐Gee
Published: June 2015

Six strategies for identifying hepatitis C virus (HCV) viremia, involving testing for HCV antibody (HCVAb) followed by a nucleic acid test (NAT) for HCV RNA when the antibody test is positive, are compared. Decision analysis was used to determine mean relative cost per person tested and outcomes of HCV viremia detection. Parameters included proportions of test population with HCVAb and viremia plus specificity, sensitivity, and cost of individual tests. For testing a population with an HCVAb seroprevalence of 3.25%, all strategies when adopting quantitative NAT vary little in cost (range, $29.50‐$30.70) and are highly viremia specific (≥0.9997). Four of the strategies using venipuncture blood for HCVAb testing (whether laboratory conducted or employing a rapid, point‐of‐care assay) and for NAT (whether done by reflex or using separately drawn blood) achieve the highest viremia sensitivities (range, 0.9950‐0.9954). Point‐of‐care HCVAb testing in fingerstick blood followed by NAT in venipuncture blood yields relatively lower viremia sensitivity (0.9301). The strategy that requires returning for NAT is even less viremia sensitive (<0.9000) because of follow‐up loss. Strategies adopting qualitative rather than quantitative NAT are slightly cheaper (range, $28.90‐$29.99), similarly viremia specific (≥0.9997), but less viremia sensitive (≤0.9456). Viremia sensitivity and specificity remain the same regardless of the proportion of HCVAb‐seropositive persons in the cohort being tested. Conclusions: Strategies involving HCVAb testing in venipuncture blood, whether laboratory conducted or using a point‐of‐care assay, when followed by quantitative NAT done reflexively or in separately drawn blood, are comparably economical and suitably viremia sensitive. Less cost‐effective is point‐of‐care HCVAb testing in fingerstick blood followed by NAT in venipuncture blood. Least cost‐effective is the strategy requiring the tested person to return for NAT. (Hepatology 2015;62:1396–1404)
Orthogonal Polarity Graphs and Sidon Sets
Authors: Tait Michael , Timmons Craig
Published: June 2015

Determining the maximum number of edges in an n‐vertex C4‐free graph is a well‐studied problem that dates back to a paper of Erdős from 1938. One of the most important families of C4‐free graphs are the Erdős‐Rényi orthogonal polarity graphs. We show that the Cayley sum graph constructed using a Bose‐Chowla Sidon set is isomorphic to a large induced subgraph of the Erdős‐Rényi orthogonal polarity graph. Using this isomorphism, we prove that the Petersen graph is a subgraph of every sufficiently large Erdős‐Rényi orthogonal polarity graph.
Graphs Containing Topological H
Authors: Ma Jie , Xie Qiqin , Yu Xingxing
Published: June 2015

Let H denote the tree with six vertices, two of which are adjacent and of degree 3. Let G be a graph and be distinct vertices of G. We characterize those G that contain a topological H in which are of degree 3 and are of degree 1, which include all 5‐connected graphs. This work was motivated by the Kelmans–Seymour conjecture that 5‐connected nonplanar graphs contain topological K5.
In vitro metabolism studies of desoxy‐methyltestosterone (DMT) and its five analogues, and in vivo metabolism of desoxy‐vinyltestosterone (DVT) in horses
Authors: Kwok Wai Him , Kwok Karen Y. , Leung David K. K. , Leung Gary N. W. , Wong Colton H. F. , Wong Jenny K. Y. , Wan Terence S. M.
Published: June 2015

The positive findings of norbolethone in 2002 and tetrahydrogestrinone in 2003 in human athlete samples confirmed that designer steroids were indeed being abused in human sports. In 2005, an addition to the family of designer steroids called ‘Madol’ [also known as desoxy‐methyltestosterone (DMT)] was seized by government officials at the US–Canadian border. Two years later, a positive finding of DMT was reported in a mixed martial arts athlete's sample. It is not uncommon that doping agents used in human sports would likewise be abused in equine sports. Designer steroids would, therefore, pose a similar threat to the horseracing and equestrian communities. This paper describes the in vitro metabolism studies of DMT and five of its structural analogues with different substituents at the 17α position (RH, ethyl, vinyl, ethynyl and 2H3‐methyl). In addition, the in vivo metabolism of desoxy‐vinyltestosterone (DVT) in horses will be presented.

The in vitro studies revealed that the metabolic pathways of DMT and its analogues occurred predominantly in the A‐ring by way of a combination of enone formation, hydroxylation and reduction. Additional biotransformation involving hydroxylation of the 17α‐alkyl group was also observed for DMT and some of its analogues. The oral administration experiment revealed that DVT was extensively metabolised and the parent drug was not detected in urine. Two in vivo metabolites, derived respectively from (1) hydroxylation of the A‐ring and (2) di‐hydroxylation together with A‐ring double‐bond reduction, could be detected in urine up to a maximum of 46 h after administration. Another in vivo metabolite, derived from hydroxylation of the A‐ring with additional double‐bond reduction and di‐hydroxylation of the 17α‐vinyl group, could be detected in urine up to a maximum of 70 h post‐administration. All in vivo metabolites were excreted mainly as glucuronides and were also detected in the in vitro studies. Copyright © 2015 John Wiley & Sons, Ltd.
Development of a time‐resolved fluorescence immunoassay for Epstein–Barr virus nuclear antigen 1‐immunoglobulin A in human serum
Authors: Chen Juan‐Juan , Liu Tian‐Cai , Liang Qian‐Ni , Dong Zhi‐Ning , Wu Ying‐Song , Li Ming
Published: June 2015

Enzyme‐linked immunosorbent assay (ELISAs) specific for Epstein–Barr virus nuclear antigen 1 (EBNA1)‐immunoglobulin A (IgA) are most commonly used in the clinical diagnosis of EBV infection. But they have a low sensitivity and the enzyme‐labeled antibodies are unstable. In this study, a novel immunoassay based on an indirect time‐resolved fluoroimmunoassay (TRFIA) was developed. Microtiter plates were coated with recombinant EBNA1. We used Eu3+‐labeled anti‐human IgA as probe. The precision, sensitivity, specificity, and stability were evaluated, and comparison with traditional and commercially available ELISAs was also made. The cut‐off value for our TRFIA was 2.7. Intra‐ and inter‐assay coefficients of variation for the TRFIA were 1.56–4.99% and 3.92–6.95%, respectively; whereas those for the ELISA were 4.54–8.16% and 7.07–10.52%, respectively. Sensitivity was obviously better than traditional ELISA when diluted positive samples serially. Additionally, stability, specificity test and comparison of sensitivity and specificity between the TRFIA and commercial ELISAs all proved satisfactory. In conclusion, the results demonstrated that EBNA1 IgA TRFIA was a sensitive immunoassay and had potential value in large‐scale screening of human serum samples in developing countries. J. Med. Virol. 87:1940–1945, 2015. © 2015 Wiley Periodicals, Inc.