bluuebunny/crossref_metadata_2025 huggingface dataset:
Probing Synergistic Effects of DNA Methylation and 2′‐β‐Fluorination on i‐Motif Stability
Authors: Abou Assi Hala , Lin Yu Chen , Serrano Israel , González Carlos , Damha Masad J.
Published: November 2017

The possible role of DNA i‐motif structures in telomere biology and in the transcriptional regulation of oncogene promoter regions is supported by several recent studies. Herein we investigate the effect of four cytidine nucleosides (and combinations thereof) on i‐motif structure and stability, namely 2′‐deoxycytidine (dC), 2′‐deoxy‐5‐methyl‐cytidine (5‐Me‐dC), 2′‐deoxy‐2′‐fluoro‐arabinocytidine (2′F‐araC), and 2′‐deoxy‐2′‐fluoro‐5‐methyl‐arabinocytidine (5‐Me‐2′F‐araC). The base pair 5‐Me‐2′F‐araC:2′F‐araC produced i‐motifs with a pH1/2 (“pKa”) value that closely matches physiological pH (7.34±0.3). NMR analysis of the most stable telomeric sequence (HJ‐2) at pH 7.0 indicated that the structure is stabilized by hybrid 5‐Me‐dC:2′F‐araC hemiprotonated base pairs and therefore highlights the significance of the interplay between base and sugar modifications on the stability of i‐motif structures.
Intra‐ versus Intermolecular Hydrogen Bonding: Solvent‐Dependent Conformational Preferences of a Common Supramolecular Binding Motif from 1H NMR and Vibrational Circular Dichroism Spectra
Authors: Demarque Daniel P. , Merten Christian
Published: November 2017

Invited for the cover of this issue are Daniel P. Demarque and Christian Merten from Ruhr University in Bochum, Germany. The image depicts a DMSO‐solvated 2,6‐pyridinediyl‐dialkylamide, the model system used in their study to investigate solute‐solvent driven conformational changes. Read the full text of the article at 10.1002/chem.201703643.
De Novo Synthesis of α‐Hydroxy Ketones by Gallic Acid‐Promoted Aerobic Coupling of Terminal Alkynes with Diazonium Salts
Authors: Alcaide Benito , Almendros Pedro , Fernández Israel , Herrera Fernando , Luna Amparo
Published: November 2017

An unprecedented metal‐free direct preparation of unprotected α‐hydroxy ketones from terminal alkynes under mild conditions with diazonium salts as the arene source and without the requirement of irradiation is described. The process is general and fully compatible with a wide variety of substitution in both reactants. Experimental and computational evidence strongly suggest the involvement of radical species in the transformation.
Macrocyclic Triruthenium Complexes Having Electronically Coupled Mixed‐Valent States
Authors: Fink Daniel , Bodensteiner Michael , Linseis Michael , Winter Rainer F.
Published: November 2017

5‐Ethynyl‐2‐furancarboxylic acid and 3‐ethynylbenzoic acid self‐assemble with [HRu(CO)Cl(PiPr3)2] to form macrocyclic C3‐symmetric triangular triruthenium alkenyl complexes [{Ru(CO)(PiPr3)2(CH=CHArCOO)}3] (Ar=C6H4: 1‐B, Ar=C4H2O: 1‐F), which were characterized by multinuclear NMR spectroscopy, high‐resolution ESI mass spectrometry, and, in the case of 1‐B, by X‐ray crystallography. Electrochemical studies indicate that the macrocycles are oxidized in three consecutive one‐electron steps. The mixed‐valent states obtained by electrochemical or chemical oxidation show signs of valence delocalization, which makes these complexes rare examples of molecule‐based conductive loops with through‐bond charge delocalization.
The effects of rewards on psychological health in the workplace: Underlying mechanisms
Authors: Pellerin Sabrina , Cloutier Julie
Published: November 2017

The effort‐reward imbalance (ERI) model in the workplace (Siegrist, 1996) suggests that inequity of rewards contributes to a degradation of mental health through a process of devaluation. The objective of our study is to test this hypothesis empirically. Data were collected from 659 agents in three call centres located in the province of Quebec. A bootstrap mediation test show that perceived inequity with respect to rewards (recognition, promotion, job security) affects the level of psychological distress through the perception of being valued by the organization. Perceived inequity affects mental health because it signals to workers the extent to which they are valued by their organization. Our correlational study provides evidence of the internal validity of the ERI model. Copyright © 2017 ASAC. Published by John Wiley & Sons, Ltd.
Magnetic particles for sugar separation from sulphuric acid solution generated during nano‐crystalline cellulose production
Authors: Sarma Saurabh J. , Ayadi Mariem , Maiti Sampa , Brar Satinder K. , Berry Richard
Published: November 2017

Nano‐crystalline cellulose (NCC) is a renewable material having different applications ranging from drug delivery to a reinforcing filling agent in polymer synthesis. Concentrated sulphuric acid is used to hydrolyze cellulosic biomass to obtain NCC. Manufacturers are keen to reuse the diluted acid solution left after the process. However, the presence of mono and oligosaccharides makes it unsuitable for repeated use. About 99 % of these compounds have been successfully separated from the acid solution by employing NaOH‐treated magnetic particles developed during this investigation. It has been observed that by NaOH treatment, zeta potential of the magnetic particles could be increased from +11 mV to +37.5 mV; correspondingly, sugar removal efficiency was increased from 23.04 % to more than 99 %. Thus a direct correlation between the change in zeta potential of the particles and sugar separation efficiency has been observed.
Impact of a draft tube on industrial‐scale Fluid Coker™ Spray Jets in fluidized beds
Authors: ZirGachian M. Ali , Briens Cedric , Berruti Franco , McMillan Jennifer
Published: November 2017

In fluidized bed reactors such as Fluid Cokers™, liquid injections are used. Good contact between liquid and bed solids is required to maximize product yields and quality, and gas‐atomized nozzles are, therefore, used in all these processes. The spray nozzle technology is known to affect the liquid distribution. Therefore, the objective of this study is to assess the effect on liquid distribution of a draft tube located downstream of the spray nozzle, inside the fluidized bed. Experiments were conducted at a relevant scale, using a commercial‐scale nozzle with a liquid flow rate of about 100 L/min in a large‐scale pilot fluid bed containing about 7 tonnes of silica sand. Liquid injected into a fluidized bed either forms liquid‐solid agglomerates or free moisture, consisting of individual particles coated with a thin layer of liquid. Several electrodes were used to map the free moisture distribution throughout the bed. A draft tube greatly improves the contact efficiency throughout the bed. It also increases the penetration of the gas‐liquid jet formed by spray inside the fluidized bed.
Visible Light Accelerated Vinyl C–H Arylation in Pd‐Catalysis: Application in the Synthesis of ortho Tetra‐substituted Vinylarene Atropisomers
Authors: Feng Jia , Li Bin , Jiang Julong , Zhang Mingkai , Ouyang Wenbai , Li Chunyu , Fu Yao , Gu Zhenhua
Published: November 2017

A visible light accelerated C–H functionalization reaction in palladium‐catalyzed arylation of vinyl arenes with diaryliodonium salts is reported in the absence of additional photosensitizer. The kinetic isotope effect (kH/kD) was changed from 3.6 (under darkness) to 1.1 when irradiated by visible light, which indicated that the C–H functionalization step was the rate determining step under darkness and significantly accelerated by the irradiation of visible light. Finally the synthesis of ortho tetra‐substituted vinylarene atropisomers with high enantiospecificity was realized via this protocol.
The Transferability of Topologically Partitioned Electron Correlation Energies in Water Clusters
Authors: Silva Arnaldo F. , Vincent Mark A. , McDonagh James L. , Popelier Paul L. A.
Published: November 2017

The electronic effects that govern the cohesion of water clusters are complex, demanding the inclusion ofN‐body, Coulomb, exchange and correlation effects. Here we present a much needed quantitative study of the effect of correlation (and hence dispersion) energy on the stabilization of water clusters. For this purpose we used a topological energy partitioning method called Interacting Quantum Atoms (IQA) to partition water clusters into topological atoms, based on a MP2/6‐31G(d,p) wave function, and modified versions of GAUSSIAN09 and the Quantum Chemical Topology (QCT) program MORFI. Most of the cohesion in the water clusters provided by electron correlation comes from intramolecular energy stabilization. Hydrogen bond‐related interactions tend to largely cancel each other. Electron correlation energies are transferable in almost all instances within 1 kcal mol−1. This observed transferability is very important to the further development of the QCT force field FFLUX, especially to the future modelling of liquid water.
The Pregnancy Related Beliefs Questionnaire (PRBQ): An examination of the psychometric properties in perinatal samples
Authors: Leach Dawn M. , Terry Philip , Nikčević Ana V.
Published: November 2017

Background

Identifying vulnerability to perinatal depression is an important public health issue. Risk factors include general and maternal‐specific dysfunctional attitudes. Scales of maternal attitudes have a number of shortcomings. Further, it is not known whether antenatal maternal attitudes predict post‐natal depression, independently of general dysfunctional attitudes (GDA). The aim of the current study was to examine the psychometric properties of the Pregnancy Related Beliefs Questionnaire (PRBQ) and to establish, prospectively, the utility of the revised PRBQ in predicting the symptoms of post‐natal depression.

Method

In Study 1, a cross‐sectional sample of 344 participants, who were either pregnant or in the post‐natal period, completed a battery of questionnaires assessing background factors, GDA, attitudes specific to motherhood (PRBQ), and depression. In Study 2, a sample of 210 women completed a battery of questionnaires, including a measure of GDA, the PRBQ‐8, and depression, on two occasions: early in the second trimester of pregnancy and post‐natally.

Results

Exploratory and confirmatory factor analyses supported a one‐factor, eight‐item measure of maladaptive attitudes specific to motherhood (PRBQ‐8). The PRBQ‐8 was found to have good convergent, concurrent, and predictive validity and high internal and test–retest reliability. A hierarchical regression analysis revealed that antenatal PRBQ‐8 scores predict the severity of post‐natal depression symptoms, after controlling for background factors, antenatal depression, and GDA.

Conclusions

The PRBQ‐8 is a psychometrically sound measure of maternal attitudes that can be used antenatally to identify women at risk of post‐natal depression.
Modeling Interface Shape in Czochralski Growth of Sapphire Crystals
Authors: Stelian Carmen , Duffar Thierry
Published: November 2017

Numerical modeling is applied to investigate the factors affecting the shape of the crystal‐melt interface in Czochralski growth of sapphire crystals having 10 cm in diameter. The modeling is performed for a 2D – axisymmetric furnace configuration, where all the furnace components are included. The shape of the crystal‐melt interface is computed by using the deformable mesh technique. Numerical results show that the conical shape of the interface depends essentially on the internal radiative heat exchanges in the semi‐transparent sapphire crystal, being less influenced by the buoyancy convection. The Marangoni effect enhances the flow near the triple solid‐liquid‐gas point, leading to convex‐concave shape of the growth interface, which is prone to facet formation. Numerically computed shape of the interface is compared to experimental results taken from literature. Applying crystal/crucible rotation has a significant impact on the flow pattern and the shape of the growth interface. Computations performed by applying only crystal rotation at rates higher than a critical value, show a reversed convection at the sample centre, underneath the crystal. This flow affects the shape of the interface, which is less curved and exhibits a convex shape. If the rotation rate is too much increased, the interface shape can be distorted by the intense flow. Application of crucible rotation intensifies the downward flow at the sample centre, leading to increased interface curvature. Rotating both the crystal and crucible in opposite directions generates a complex flow pattern, but has no flattening effect on the interface.
Thickness‐Dependent Tensile and Fatigue Behavior of A Single‐Slip‐Oriented Cu Single Crystal
Authors: Liu Ming‐Qiu , Liu Ya‐Lan , Yan Ying , Han Dong , Li Xiao‐Wu
Published: November 2017

To explore the micro‐mechanism for the size effect of the mechanical behavior of metallic crystals, the tensile and fatigue behavior of Cu single crystal with t of 0.1−2.0 mm is investigated. The results show that with the reduction of t, an obvious increase in σYS and a slight decrease in σUTS take place; meanwhile, the δ evidently reduces, especially as t < 0.6 mm, while the Nf first sharply increases and then decreases at a constant stress amplitude of 80 MPa. The activated slip system reduces with t under tensile loading, and the fracture modes are transferred from ductile to slip separation rupture, whereas under cyclic loading, slip separation rupture becomes dominant especially at t = 2.0 and 0.1 mm. Correspondingly, the tensile microstructures are transformed from the cell‐walls to dislocation cells, while dislocation cells are the dominant microstructure in fatigued specimens, and the dislocation density obviously decreases with decreasing t. In a word, a strong dependence of tensile and fatigue behavior on t is exhibited for the Cu single crystal.
Synthesis, Structure and Properties of Formamidine‐templated Metal Formate Crystals
Authors: Luo Chunhua , Fang Minjie , Luo Qianqian , Lin Hechun , Zhang Yuanyuan , Yue Fangyu , Xiang Pinghua , Peng Hui
Published: November 2017

This work reports the preparation of crystals of two metal organic frameworks [(NH2CHNH2)][Zn(HCOO)3] (1) and [(NH2CHNH2)2][Cu2(HCOO)6] (2) by using the solvent evaporation method. Under the same experimental conditions, the obtained crystals show different crystal structures. The complex 1 forms 3D structure geometry with one Zn(Ⅱ) ion in the center of an octahedral coordination environment, which is bridged with six nearest Zn(Ⅱ) ions by the formate ligands. The 3D scaffold of the complex 2 consists of two copper ions (Cu1 and Cu2) in the center of an octahedral coordination environment bridged by formate ligands. Magnetic study shows diamagnetic susceptibility for [NH2CHNH2][Zn(HCOO)3] and antiferromagnetic coupling between the Cu(Ⅱ) ions for [(NH2CHNH2)2][Cu2(HCOO)6].
Multiple‐Trapping Model for the Charge Recombination Dynamics in Mesoporous‐Structured Perovskite Solar Cells
Authors: Wang Hao‐Yi , Wang Yi , Hao Ming‐Yang , Qin Yujun , Fu Li‐Min , Guo Zhi‐Xin , Ai Xi‐Cheng , Zhang Jian‐Ping
Published: November 2017

The photovoltaic performance of organic–inorganic hybrid perovskite solar cells has reached a bottleneck after rapid development in last few years. Further breakthrough in this field requires deeper understanding of the underlying mechanism of the photoelectric conversion process in the device, especially the dynamics of charge‐carrier recombination. Originating from dye‐sensitized solar cells (DSSCs), mesoporous‐structured perovskite solar cells (MPSCs) have shown many similarities to DSSCs with respect to their photoelectric dynamics. Herein, by applying the multiple‐trapping model of the charge‐recombination dynamic process for DSSCs in MPSCs, with rational modification, a novel physical model is proposed to describe the dynamics of charge recombination in MPSCs that exhibits good agreement with experimental data. Accordingly, the perovskite‐ and TiO2‐dominating charge‐recombination processes are assigned and their relationships with the trap‐state distribution are also discussed. An optimal balance between these two dynamic processes is required to improve the performance of mesoporous‐structured perovskite devices.
Topology of syngameons
Authors: Boecklen William J.
Published: November 2017

Syngameons are sets of species linked by interspecific hybridization. Common observations regarding the structure of syngameons are that hybridization propensity is not uniform across species and that patterns of hybridization are dominated by a few species. I use computer simulations to test these claims in naturally occurring syngameons selected from the literature and from personal observation. Natural syngameons, especially those involving plants, typically exhibit nonrandom structure: The first three order statistics for the number of hybrid partners and the variance in the number of hybrid partners are larger than chance alone would predict. The structure of two insect syngameons examined is not significantly different from random. To test a hypothesis that variation in hybridization propensity across species in natural syngameons is simply an artifact of hybridization opportunity, I examine the structure of four artificial syngameons (fertility relationships) produced by full diallel crosses. Three of four artificial syngameons exhibit nonrandom structure, as the observed variation in number of successful crosses is larger than chance alone would predict. In general, there are no significant results involving the order statistics. Finally, I discuss biogeographic, ecological, and phylogenetic hypotheses for variation in hybridization propensity across species in natural syngameons.
The effects of elevated CO2 (0.5%) on chloroplasts in the tetraploid black locust (Robinia pseudoacacia L.)
Authors: Cao Yuan , Jiang Mingquan , Xu Fuling , Liu Shuo , Meng Fanjuan
Published: November 2017

Some ploidy plants demonstrate environmental stress tolerance. Tetraploid (4×) black locust (Robinia pseudoacacia L.) exhibits less chlorosis in response to high CO2 than do the corresponding diploid (2×) plants of this species. We investigated the plant growth, anatomy, photosynthetic ability, chlorophyll (chl) fluorescence, and antioxidase activities in 2× and 4× black locusts cultivated under high CO2 (0.5%). Elevated CO2 (0.5%) induced a global decrease in the contents of total chl, chl a, and chl b in 2× leaves, while few changes were found in the chl content of 4× leaves. Analyses of the chl fluorescence intensity, maximum quantum yield of photosystem II (PSII) photochemistry (Fv/Fm), K‐step (Vk), and J‐step (VJ) revealed that 0.5% CO2 had a negative effect on the photosynthetic capacity and growth of the 2× plants, especially the performance of PSII. In contrast, there was no significant effect of high CO2 on the growth of the 4× plants. These analyses indicate that the decreased inhibition of the growth of 4× plants by high CO2 (0.5%) may be attributed to an improved photosynthetic capacity, pigment content, and ultrastructure of the chloroplast compared to 2× plants.
Hidden Hysteretic Behavior of a Paramagnetic Iron(II) Network Revealed by Light Irradiation
Authors: Ndiaye Mame Mguenar , Pillet Sébastien , Bendeif El‐Eulmi , Marchivie Mathieu , Chastanet Guillaume , Boukheddaden Kamel , Triki Smail
Published: November 2017

The paramagnetic coordination polymer [Fe(3phOH‐trz){Pt(CN)4}]·2H2O [3phOH‐trz = 4‐(3‐hydroxyphenyl)‐1,2,4‐triazole] was obtained through the reaction of an iron(II) salt with the 3phOH‐trz ligand and a [Pt(CN)4]2– anion. Its structure consists of two‐dimensional {FePt(CN)4} layers linked by π‐stacking interactions and a strong H‐bonding network between water molecules and the hydroxy groups of the organic neutral ligand. From the paramagnetic high‐spin (HS) state at 10 K, irradiation at λ = 830 nm led to the fully low‐spin (LS) state, as determined through the reverse light‐induced excited spin‐state trapping (LIESST) process. As the compound is warmed up, this LS state undergoes a thermally induced spin transition to high spin at ca. 105 K. This photoswitching process is reversible, and the paramagnetic state can be recovered through light irradiation at λ = 510 nm below 105 K. Moreover, permanent irradiation (λ = 830 nm) revealed a hidden hysteresis loop with a width of 37 K. Photocrystallographic experiments did not detect any structural phase transition upon excitation but underlined that elastic frustration might be responsible for the inhibition of the spin crossover in this compound and allowed the observation of the hidden hysteresis loop.
The Baldwin Rearrangement: Synthesis of 2‐Acylaziridines
Authors: Tangara Salia , Kanazawa Alice , Py Sandrine
Published: November 2017

The Baldwin rearrangement is a thermally induced ring contraction of 4‐isoxazolines into 2‐acylaziridines. The reaction yields highly strained nitrogen‐containing three‐membered‐ring compounds from readily available five‐membered N‐O heterocycles. Diversely substituted isoxazolines are directly transformed into a variety of highly functionalized 2‐acylaziridines in a stereocontrolled process. In this review mechanistic aspects and stereoselectivity of this rearrangement are discussed. Although still undervalued, the Baldwin rearrangement may have significant applications in the synthesis of complex aziridine‐containing targets such as natural products or pharmaceuticals.
Anomalous ortho‐Proton Acidities of the para‐Haloanisoles
Authors: Slocum D. W. , Maulden Emily A. , Whitley Paul E. , Reinscheld Thomas K. , Jackson Colleen S. , Maddox Jeremy B.
Published: November 2017

This communication presents clear evidence for an aryl meta‐position acidification effect by a para‐situated bromine or iodine substituent. This effect is manifested at the ortho‐protons of both para‐bromoanisole and para‐iodoanisole. There are indications in the computational literature of an meta‐position acidification effect provided by a substituent bromine; there is also experimental evidence obtained mostly at cryoscopic temperatures. No conventional electronic effect can account for this acidification. Herein, both experimental evidence and computational justification are presented for this unusual meta‐acidification, not only for bromine, but for iodine as well.
Volumetric Hydrogen Storage Capacity in Metal–Organic Frameworks
Authors: Balderas‐Xicohténcatl R. , Schlichtenmayer Maurice , Hirscher Michael
Published: November 2017

Molecular hydrogen storage in metal–organic frameworks (MOFs) is one possibility for on‐board storage in fuel‐cell vehicles, but so far generally only the gravimetric hydrogen storage capacity has been considered. Here we analyze the volumetric absolute hydrogen uptake of many MOFs measured at 77 K and 2.0–2.5 MPa in our laboratory in recent years and correlate these to their structure. A linear relation is found for the volumetric absolute hydrogen uptake as a function of the volumetric surface area, which yields the same hydrogen surface density as in Chahine's rule. Furthermore, the experimental data show a correlation between the specific volume and the specific surface area, which is used to develop a phenomenological model for the volumetric absolute uptake as a function of the gravimetric absolute uptake. Most of the MOFs follow this relation. However, the interpenetrated framework, CFA‐7, shows the strongest deviation and the highest volumetric absolute hydrogen storage capacity at 77 K and 2.0 MPa.
Recent Progress in Solution‐Processed Copper‐Chalcogenide Thin‐Film Solar Cells
Authors: Li Wenjie , Tan Joel Ming Rui , Leow Shin Woei , Lie Stener , Magdassi Shlomo , Wong Lydia Helena
Published: November 2017

Solution‐based thin‐film semiconductors offer a promising path for the mass production of low‐cost solar cells prepared at low temperatures. Thin‐film Cu‐based chalcogenides such as Cu(In,Ga)(S,Se)2 (CIGSSe) and Cu2ZnSn(S,Se)4 (CZTSSe) hold great promise and have been regarded as viable candidates because of the abundance of their constituent elements and environmentally nontoxic nature. This Review summarizes the recent progress in solution‐processed Cu chalcogenides (CuInSe2, Cu(In,Ga)(S,Se)2, Cu2ZnSnS4, Cu2ZnSn(S,Se)4) for thin‐film solar cells, with emphasis on the precursor solution deposited by spray pyrolysis and spin coating. The general aspects, current status, and recent research highlights are introduced and analyzed in detail. Finally, the challenges and future prospects of these solar cells are also discussed.
Early‐onset epileptic encephalopathy and severe developmental delay in an association with de novo double mutations in NF1 and MAGEL2
Authors: Akamine Satoshi , Sagata Noriaki , Sakai Yasunari , Kato Takahiro A. , Nakahara Takeshi , Matsushita Yuki , Togao Osamu , Hiwatashi Akio , Sanefuji Masafumi , Ishizaki Yoshito , Torisu Hiroyuki , Saitsu Hirotomo , Matsumoto Naomichi , Hara Toshiro , Sawa Akira , Kano Shinichi , Furue Masutaka , Kanba Shigenobu , Shaw Chad A. , Ohga Shouichi
Published: November 2017

Advance in the exome‐wide sequencing analysis contributes to identifying hundreds of genes that are associated with early‐onset epileptic encephalopathy and neurodevelopmental disorders. On the basis of massive sequencing data, functional interactions among different genes are suggested to explain the common molecular pathway underlying the pathogenic process of these disorders. However, the relevance of such interactions with the phenotypic severity or variety in an affected individual remains elusive. In this report, we present a 45‐year‐old woman with neurofibromatosis type 1 (NF1), infantile‐onset epileptic encephalopathy, and severe developmental delay. Whole‐exome sequencing identified de novo pathogenic mutations in NF1 and the Schaaf‐Yang syndrome‐associated gene, MAGEL2. Literature‐curated interaction data predicted that NF1 and MAGEL2 proteins were closely connected in this network via their common interacting proteins. Direct conversion of fibroblasts into neurons in vitro showed that neuronal cells from 9 patients with NF1 expressed significantly lower levels of MAGEL2 (54%, p = 0.0047) than those from healthy individuals. These data provide the first evidence that pathogenic mutations of NF1 deregulate the expression of other neurodevelopmental disease‐associated genes. De novo mutations in multiple genes may lead to severe developmental phenotypes through their cumulative effects or synergistic interactions.
Periphyton and abiotic factors influencing arsenic speciation in aquatic environments
Authors: Lopez Adeline R. , Silva Silmara Costa , Webb Samuel M. , Hesterberg Dean , Buchwalter David B.
Published: November 2017

Benthic periphytic biofilms are important food sources at the base of aquatic ecosystems. These biofilms also sit at the interface of oxic waters and hypoxic sediments, and can be influenced by or influence trace element speciation. In the present study, we compared arsenic (As) enrichment in periphyton exposed to arsenate (As[V]) or arsenite (As[III]) (20 μg/L, static renewal, 7 d), and we found similar accumulation patterns of total As (101 ± 27 and 88 ± 22 mg kg−1 dry wt, respectively). Periphyton As was 6281- and 6684-fold higher than their aqueous exposures and occurred primarily as As(V). When these biofilms were fed to larval mayflies, similar total As tissue concentrations (13.9 and 14.6 mg kg−1 dry wt, respectively) were observed, revealing significant biodilution (∼ 10% of their dietary concentrations). Finally, we investigated the influence of aeration and periphyton presence on As speciation in solutions and solid phases treated with As(III). Predominantly As(III) solutions were slowly oxidized over a 7-d time period, in the absence of periphyton, and aeration did not strongly affect oxidation rates. However, in the presence of periphyton, solution and solid-phase analyses (by microscale x-ray absorption spectroscopy) showed rapid As(III) oxidation to As(V) and an increasing proportion of organo-As forming over time. Thus periphyton plays several roles in As environmental behavior: 1) decreasing total dissolved As concentrations via abiotic and biotic accumulation, 2) rapidly oxidizing As(III) to As(V), 3) effluxing organo-As forms into solution, and 4) limiting trophic transfer to aquatic grazers. Environ Toxicol Chem 2018;37:903–913. © 2017 SETAC
Benchmarking commodity investments
Authors: Blocher Jesse , Cooper Ricky , Molyboga Marat
Published: November 2017

While much is known about the financialization of commodities, less is known about how to profitably invest in commodities. We develop a four‐factor asset pricing model of commodity returns. Our four‐factor model prices both commodity spot and term risk premia in an intuitive manner related to investable portfolios. The straightforward construction of our factors is an improvement over previous models. Furthermore, our four‐factor model prices commodity risk premia using both sorted portfolios and risk adjusted alphas as benchmarks. Thus, we feel it is an appropriate benchmark to evaluate commodity investment vehicles.
Synthesis, Characterization, and Photonic Efficiency of Novel Photocatalytic Niobium Oxide Materials
Authors: Morais Lidiane A. , Adán Cristina , Araujo Antonio S. , Guedes Ana P. M. A. , Marugán Javier
Published: November 2017

The application of niobium oxides as photocatalytic materials for the removal of contaminants is scarcely reported in the literature. This work reports the methodology to synthesize four different mesoporous niobium oxide materials and the correlation between the physicochemical properties and the photocatalytic activity. X‐ray diffraction, UV–vis diffuse reflectance spectra (DRS), transmission electron microscopy, and nitrogen adsorption techniques are used to characterize the structure and composition of the obtained materials. The photocatalytic oxidation of methanol is used as reaction test to assess the photocatalytic activities and photonic efficiencies of the materials as a function of the catalyst concentration. Nb2O5 materials display lower reaction rates, which can be attributed to the relatively high average particle size. By contrast, NaNbO3 materials show higher activity, especially for high catalyst loading. No significant differences in absorption and scattering of light are observed among the materials, indicating that the higher photonic efficiency of NaNbO3 should be the result of a lower charge recombination derived from its microstructure, sodium composition, low particle size, and high specific surface area of these materials.
Archaeological prospection of the nearshore and intertidal area using ultra‐high resolution marine acoustic techniques: Results from a test study on the Belgian coast at Ostend‐Raversijde
Authors: Missiaen Tine , Evangelinos Dimitris , Claerhout Chloe , De Clercq Maikel , Pieters Marnix , Demerre Ine
Published: November 2017

The coastal site of Ostend‐Raversijde in Belgium is known for its archaeological artifacts, mainly from Roman and medieval times. In recent years, detailed geophysical and geotechnical investigations have been carried out here to test the efficiency of these techniques for geoarchaeological prospection of the subtidal and intertidal zone. Very high‐resolution 2D subbottom profiling using a parametric echosounder evidenced a highly complex system of paleogullies and tidal channels, some of which can be linked to the medieval peninsulaTesterepand the drowned settlement ofWalraversijde. For the first time marine seismic and terrestrial electromagnetic induction (EMI) data were fully integrated in the same intertidal area. The parametric echosounder proved a highly effective tool to map the (partly excavated) peat layers and submerged landscape in high detail, even in extremely shallow water. Using a novel multitransducer parametric echosounder (SES‐2000 Quattro), unique 3D imaging of the peat exploitation pattern was possible with unprecedented detail (submeter level). This sets a new standard for shallow water research and opens important new perspectives for geoarchaeological studies in nearshore areas.
Disparities in rate, triggers, and management in pediatric and adult cases of suspected drug‐induced anaphylaxis in Canada
Authors: Gabrielli Sofianne , Clarke Ann E. , Eisman Harley , Morris Judy , Joseph Lawrence , La Vieille Sebastien , Small Peter , Lim Rodrick , Enarson Paul , Zelcer Michal , Chan Edmond S. , Mill Chris , Ben‐Shoshan Moshe
Published: November 2017

Introduction

Data is sparse on drug‐induced anaphylaxis (DIA) and there have not been studies assessing the differences in clinical characteristics and management of DIA between adults and children.

Objective

We assessed the percentage, diagnosis, and management of DIA among all anaphylaxis visits in three pediatric and one adult emergency departments (ED) across Canada.

Methods

Children presenting to the Montreal Children's Hospital (MCH), British Columbia Children's Hospital (BCCH), and Children's Hospital at London Health Sciences Center and adults presenting to Hôpital du Sacré‐Coeur with anaphylaxis were recruited as part of the Cross‐Canada Anaphylaxis Registry. A standardized data form documenting the reaction and management was completed and patients were followed annually to determine assessment by allergist and use of confirmatory tests.

Results

From June 2012 to May 2016, 51 children were recruited from the pediatric centers and 64 adults from the adult center with drug‐induced anaphyalxis. More than half the cases were prospectively recruited. The percentage of DIA among all cases of anaphylaxis was similar in all three pediatric centers but higher in the adult center in Montreal. Most reactions in children were triggered by non‐antibiotic drugs, and in adults, by antibiotics. The majority of adults and a third of children did not see an allergist after the initial reaction. In those that did see an allergist, diagnosis was established by either a skin test or an oral challenge in less than 20% of cases.

Conclusions

Our results reveal disparities in rate, culprit, and management of DIA in children versus adults. Further, most cases of suspected drug allergy are not appropriately diagnosed. Guidelines to improve assessment and diagnosis of DIA are required.
Stimuli‐responsive Supra‐biomolecular Nanoassemblies of Cucurbit[7]uril with Bovine Serum Albumin: Drug Delivery and Sensor Applications
Authors: Barooah Nilotpal , Khurana Raman , Bhasikuttan Achikanath C. , Mohanty Jyotirmayee
Published: November 2017

Construction and characterization of stimuli‐responsive supra‐biomolecular nanoassembly between cucurbit[7]uril (CB7) and bovine serum albumin (BSA), uptake and release of doxorubicin (DOX) in live cells, the enhanced sensitivity of brilliant green (BG) and the metal ion‐induced relocation of neutral red (NR) dye to BSA have been discussed in this review. The fluorescence intensity of DOX is largely quenched in the presence of nanoassembly which recovers with adamantylamine or by changing the pH of the solution, indicating the significant uptake and release of DOX. Whereas, the interaction of BG with CB7‐BSA assembly leads to a huge fluorescence enhancement ∼350‐fold through ternary complex formation. In another study, the supramolecular pKa tuning of nanoassembly encapsulated NR dye with metal ion and the consequent relocation of NR from CB7 cavity to the hydrophobic pocket of BSA have been demonstrated. All these studies show promising applications in drug delivery and on‐off sensor.
Let's Think Creatively: Designing a High School Lesson on Metaphorical Creativity for English L2 Learners
Authors: Wang Hung‐chun
Published: November 2017

This article reports on a practitioner research study exploring how creative thinking activities can be designed and integrated into high school English classes. It delineates the process of developing a metaphorical creativity workshop for year 11 students in Taiwan and demonstrates the students’ workshop experiences and learning outcomes. Results of the study reveal that the workshop stimulated the students’ metaphorical creativity and expanded their English‐language knowledge. Findings also suggest that the workshop can be further improved in several ways, such as including more diverse topics about language creativity and combining creativity training with textbook content. Overall, this study provides essential insights that can help English teachers design creative thinking activities and integrate them into high school English curricula effectively.
Low‐level perfluorooctanoic acid enhances 3 T3‐L1 preadipocyte differentiation via altering peroxisome proliferator activated receptor gamma expression and its promoter DNA methylation
Authors: Ma Yue , Yang Jie , Wan Yanjian , Peng Yang , Ding Shuai , Li Yuanyuan , Xu Bing , Chen Xi , Xia Wei , Ke Yuebin , Xu Shunqing
Published: November 2017

Recent studies suggest that perfluorooctanoic acid (PFOA) can play a role in the development of obesity; however, the associated mechanisms are poorly understood. We investigated how PFOA exposure affected the differentiation of 3 T3‐L1 preadipocytes and the associated transcriptional and epigenetic mechanisms. Cells treated with different doses of PFOA (ranging from 0.01 to 100 μg ml–1) were assessed for proliferation, differentiation and triglyceride accumulation. The gene expression levels of peroxisome proliferator activated receptor gamma (PPARγ) and its target genes were measured. DNA methylation levels of PPARγ promoter and global DNA methylation levels were also tested. We found a concentration‐dependent enhancement of adipocyte proliferation and differentiation following PFOA exposure. PFOA also induced a significant concentration‐dependent increase in the accumulation of lipid and triglyceride. Increased gene expression was also observed for PPARγ, CCAAT/enhancer binding proteins α, fatty acid binding protein 2 and lipoprotein lipase in differentiated cells after PFOA exposure. The ability of PFOA to induce adipogenesis was blocked by GW9662, a known PPARγ antagonist. In addition, significant demethylation of the cytosine–phosphate–guanine sites in the PPARγ promoter was observed after exposure to PFOA. In addition, PFOA exposure resulted in decreased global DNA methylation and increased expression levels of DNA methyltransferases genes. We found that treatment with low levels of PFOA can induce adipogenic differentiation in preadipocytes, and the underlying mechanisms probably involve the activation of PPARγ transcription and demethylation of PPARγ promoter.
Trichostatin A alters cytoskeleton and energy metabolism of pancreatic adenocarcinoma cells: An in depth proteomic study
Authors: Dalla Pozza Elisa , Manfredi Marcello , Brandi Jessica , Buzzi Arianna , Conte Eleonora , Pacchiana Raffaella , Cecconi Daniela , Marengo Emilio , Donadelli Massimo
Published: November 2017

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal of all human cancers with a high mortality rate. Resistance to conventional treatments and chemotherapeutics is a typical feature of PDAC. To investigate the causes of drug resistance it is essential to deeply investigate the mechanism of action of chemotherapeutics. In this study, we performed an in depth shotgun proteomic approach using the label‐free proteomic SWATH‐MS analysis to investigate novel insights of the mechanism of action of the histone deacetylase (HDAC) inhibitor trichostatin A (TSA) in PDAC cells. This proteomic analysis in PaCa44 cells and data elaboration of TSA‐regulated proteins by bioinformatics showed an overall up‐regulation of cytokeratins and other proteins related to the cytoskeleton organization, keratinization, and apoptotic cell death. On the contrary, a large amount of the down‐regulated proteins by TSA treatment belongs to the cellular energetic metabolism and to the machinery of protein synthesis, such as ribosomal proteins, determining synergistic cell growth inhibition by the combined treatment of TSA and the glycolytic inhibitor 2‐deoxy‐d‐glucose in a panel of PDAC cell lines. Data are available via ProteomeXchange with identifier PXD007801.
Combined molecular and periodic DFT analysis of the adsorption of co macrocycles on graphene
Authors: Calborean Adrian , Morari Cristian , Maldivi Pascale
Published: November 2017

The molecular doping of graphene with π‐stacked conjugated molecules has been widely studied during the last 10 years, both experimentally or using first‐principle calculations, mainly with strongly acceptor or donor molecules. Macrocyclic metal complexes have been far less studied and their behavior on graphene is less clear‐cut. The present density functional theory study of cobalt porphyrin and phthalocyanine adsorbed on monolayer or bilayer graphene allows to compare the outcomes of two models, either a finite‐sized flake of graphene or an infinite 2D material using periodic calculations. The electronic structures yielded by both models are compared, with a focus on the density of states around the Fermi level. Apart from the crucial choice of calculation conditions, this investigation also shows that unlike strongly donating or accepting organic dopants, these macrocycles do not induce a significant doping of the graphene sheet and that a finite size model of graphene flake may be confidently used for most modeling purposes. © 2017 Wiley Periodicals, Inc.
A case of retroperitoneal para‐aortic ectopic pregnancy detected by sonography
Authors: Zhang Min , Qin Ling‐Ling
Published: November 2017

Retroperitoneal ectopic pregnancy is extremely rare. We present a case of a retroperitoneal ectopic pregnancy with a gestational sac located to the left of the abdominal aorta and of the left renal vessels at 9 weeks of gestation. Careful transabdominal sonographic examination is suggested when an ectopic pregnancy is suspected and the examination of the pelvis is negative.
Low‐intensity vibration increases cartilage thickness in obese mice
Authors: Pamon Tee , Bhandal Vincent , Adler Benjamin J. , Ete Chan M. , Rubin Clinton T.
Published: November 2017

Obesity is associated with an elevated risk of osteoarthritis (OA). We examined here whether high fat diet administered in young mice, compromised the attainment of articular cartilage thickness. Further, we sought to determine if low‐intensity vibration (LIV) could protect the retention of articular cartilage in a mouse model of diet‐induced obesity. Five‐week‐old, male, C57BL/6 mice were separated into three groups (n = 10): Regular diet (RD), High fat diet (HF), and HF + LIV (HFv; 90 Hz, 0.2g, 30 min/d, 5 d/w) administered for 6 weeks. Additionally, an extended HF diet study was run for 6 months (LIV at 15 m/d). Articular cartilage and subchondral bone morphology, and sulfated GAG content were quantified using contrast agent enhanced μCT and histology. Gene expression within femoral condyles was quantified using real‐time polymerase chain reaction. Contrary to our hypothesis, HF cartilage thickness was not statistically different from RD. However, LIV increased cartilage thickness compared to HF, and the elevated thickness was maintained when diet and LIV were extended into adulthood. RT‐PCR analysis showed a reduction of aggrecan expression with high fat diet, while application of LIV reduced the expression of degradative MMP‐13. Further, long‐term HF diet resulted in subchondral bone thickening, compared to RD, providing early evidence of OA pathology—LIV suppressed the thickening, such that levels were not significantly different from RD. These data suggest that dynamic loading, via LIV, protected the retention of cartilage thickness, potentially resulting in joint surfaces better suited to endure the risks of elevated loading that parallel obesity. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:751–759, 2018.
Application of visible/near infrared spectroscopy to quality control of fresh fruits and vegetables in large‐scale mass distribution channels: a preliminary test on carrots and tomatoes
Authors: Beghi Roberto , Giovenzana Valentina , Tugnolo Alessio , Guidetti Riccardo
Published: November 2017

BACKGROUND

The market for fruits and vegetables is mainly controlled by the mass distribution channel (MDC). MDC buyers do not have useful instruments to rapidly evaluate the quality of the products. Decisions by the buyers are driven primarily by pricing strategies rather than product quality. Simple, rapid and easy‐to‐use methods for objectively evaluating the quality of postharvest products are needed. The present study aimed to use visible and near‐infrared (vis/NIR) spectroscopy to estimate some qualitative parameters of two low‐price products (carrots and tomatoes) of various brands, as well as evaluate the applicability of this technique for use in stores.

RESULTS

A non‐destructive optical system (vis/NIR spectrophotometer with a reflection probe, spectral range 450–1650 nm) was tested. The differences in quality among carrots and tomatoes purchased from 13 stores on various dates were examined. The reference quality parameters (firmness, water content, soluble solids content, pH and colour) were correlated with the spectral readings. The models derived from the optical data gave positive results, in particular for the prediction of the soluble solids content and the colour, with better results for tomatoes than for carrots.

CONCLUSION

The application of optical techniques may help MDC buyers to monitor the quality of postharvest products, leading to an effective optimization of the entire supply chain. © 2017 Society of Chemical Industry
Prognostic significance of the distribution of lymph node metastasis in rectal cancer after neoadjuvant chemoradiation
Authors: Lee Soo Young , Kim Chang Hyun , Kim Young Jin , Kim Hyeong Rok
Published: November 2017

Background

This study aimed to evaluate the prognostic significance of lymph node distribution (LND) in rectal cancer after neoadjuvant chemoradiation.

Methods

A total of 519 patients with primary rectal cancer who underwent curative resection after neoadjuvant chemoradiation were included. LND was classified into four groups: LND0, no lymph node metastasis (368/519, 70.9%); LNDp, lymph node metastasis along the inferior mesenteric artery (proximal) (15/519, 2.9%); LNDm, lymph node metastasis at the mesorectum (109/519, 21.0%); and LNDpm, lymph node metastasis at both the proximal and mesorectal areas (27/519, 5.2%). Clinicopathologic characteristics were analyzed to identify independent prognostic factors.

Results

In patients with positive lymph nodes, LND showed superior discrimination for 3‐year DFS (LNDp 67.7%, LNDm 48.9%, and LNDpm 26.8%, P = 0.003) and 3‐year LRFS (LNDp 93.3%, LNDm 81.4%, and LNDpm 60.5%, P = 0.009) compared to ypN stage (3‐year DFS, N1 47.8%, N2 40.0%, P = 0.184; 3‐year LRFS, N1 79.4%, N2 75.2%, P = 0.527). On multivariate survival analysis, LND was an independent prognostic factor for LRFS (P = 0.030) in patients with positive lymph nodes.

Conclusions

LND may improve the prognostic value of the ypTNM staging system for patients with node‐positive rectal cancer after neoadjuvant chemoradiation, particularly in terms of local recurrence.