bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and characterization of ZnO nanoflowers using Chlamydomonas reinhardtii: A green approach
Authors: Rao M. Divya , Gautam P.
Published: February 2016

Recently, there has been a lot of interest in the synthesis and application of nanoparticles with anisotropic morphologies. The focus of this study has been to use a biologically mediated, low temperature approach for the synthesis of zinc oxide nanoflowers. “Green” methods have a number of advantages over conventional approaches; these include the use of environmentally benign reactants and its economic feasibility. The cell free extract of Chlamydomonas reinhardtii, a fresh water microalga was used to synthesize the nanoflowers. The nanoflowers were composed of individual nanorods that assembled to form flower‐like structures. The nanorods measured 330 nm in length and these nanorods self‐assembled to form porous nanosheets that were found to measure 55–80 nm. Particle size analysis revealed that the larger porous nanoflowers approximately measured 4 µm. Powder X‐ray diffraction studies revealed that the zinc oxide nanoflowers had a hexagonal wurtzite crystal structure. Fourier transform infrared spectroscopy analysis suggested that algal biomolecules were responsible for the synthesis and stabilization of zinc oxide nanostructures. These nanoflowers demonstrate enhanced photocatalytic activity against methyl orange (MO) under natural sunlight. The effects of dye concentration and catalyst dosage on photocatalysis were also studied. The present approach represents a novel, eco‐friendly method to synthesize zinc oxide nanoflowers that have potential applications in water treatment and dye degradation. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1020–1026, 2016
Biomethanization of Brewer's spent grain evaluated by application of the Anaerobic Digestion Model No.1
Authors: Colussi Iginio , Cortesi Angelo , Gallo Vittorino , Vitanza Rosa
Published: February 2016

Brewer's spent grain (BSG), the residual solid fraction of the final mash process of malting, is a main waste fraction of beer production, recently considered as possible substrate for biovalorization by anaerobic digestion (AD).

In this article, the biomethanization of BSG was evaluated by performing biochemical methane potential (BPM) tests. The obtained specific methane production (SMP) was 0.284 LCH4·g−1COD. The process was modelled by implementing the Anaerobic Digestion Model No.1 (ADM1) into AQUASIM software with the focus on the disintegration and hydrolysis step. The calibrated disintegration rate for BSG was equal to 0.823 d−1 and the hydrolysis rate constants varied from 0.124 d−1 for lipids to 1.056 d−1 for proteins.

The obtained results showed a good efficiency in treating BSG with anaerobic digestion. The practical conversion degree of the biowaste COD into methane was equal to 81.1%, a high value for a substrate with an elevated solid content. Moreover, the estimated values of disintegration and hydrolysis rates complied with the retention time values generally adopted in an anaerobic digestor. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1055–1060, 2016
Tea waste and food waste as a potential feedstock for biogas production
Authors: Yadav Dipti , Barbora Lepakshi , Rangan Latha , Mahanta Pinakeswar
Published: February 2016

Recent strategies on fuel‐development to reduce oil dependency to mitigate greenhouse gas emissions and to utilize domestic resources have generated interest in the search for alternative sources of fuel supplies. In this context, the industrial waste may be regarded as potential alternatives for biogas production. This study entails a detailed characterization of tea waste and food waste to evaluate their potential as an alternate feedstock to cattle dung for biogas production. The samples were characterized for volatile matter, moisture content, ash content and carbon hydrogen nitrogen (CHN). Property analysis of the biomass was also done by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The volatile matter content in tea and food waste was found to be 64.17% and 36.05% respectively, which is quite encouraging. The carbon‐to‐nitrogen (C:N) ratio, chemical oxygen demand and total solids of the sample also attributed its suitability for biogas production. The thermal behavior and heating values interpreted higher lignin content in tea waste. The lab scale study was conducted with combination of food waste/cattle dung and tea waste/cattle dung that showed higher biogas production in comparison to cattle dung alone implying their potential as biogas feedstock. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1247–1253, 2016
Influence of boundary conditions on the out‐of‐plane response of brick masonry walls in buildings with RC slabs
Authors: Tondelli Marco , Beyer Katrin , DeJong Matthew
Published: February 2016

In modern unreinforced masonry buildings with stiff RC slabs, walls of the top floor are most susceptible to out‐of‐plane failure. The out‐of‐plane response depends not only on the acceleration demand and wall geometry but also on the static and kinematic boundary conditions of the walls. This paper discusses the influence of these boundary conditions on the out‐of‐plane response through evaluation of shake table test results and numerical modelling. As a novum, it shows that the in‐plane response of flanking elements, which are orthogonal to the wall whose out‐of‐plane response is studied, has a significant influence on the vertical restraint at the top of the walls. The most critical configuration exists if the flanking elements are unreinforced masonry walls that rock. In this case, the floor slabs can uplift, and the out‐of‐plane load‐bearing walls loose the vertical restraint at the top. Numerical modelling confirms this experimentally observed behaviour and shows that slab uplift and the difference in base and top excitation have a strong influence on the out‐of‐plane response of the walls analysed. Copyright © 2016 John Wiley & Sons, Ltd.
SER analysis of selective DF relaying based OWC system with generalised turbulence
Authors: Sharma Nikhil , Bansal Ankur , Garg Parul
Published: February 2016

In this paper, we analyse the error performance of selective decode‐and‐forward based optical wireless communication system utilising subcarrier intensity modulation for arbitrary M‐ary signalling over generalised
‐distributed atmospheric turbulence. The
‐distribution is a generic statistical model for characterising the atmospheric turbulence‐induced fading and unifies several existing statistical models for atmospheric turbulence. In particular, we derive a closed‐form expression of the approximate average symbol error rate for the considered system with independent and non‐identically distributed optical links. Furthermore, we analytically evaluate the diversity order for various distributions (e.g. gamma–gamma distribution, K‐distribution and negative exponential distribution), characterised by the generalised
‐distribution model. The analytical results have been verified by simulations. Copyright © 2016 John Wiley & Sons, Ltd.
From evoked potentials to cortical currents: Resolving V1 and V2 components using retinotopy constrained source estimation without fMRI
Authors: Inverso Samuel A. , Goh Xin‐Lin , Henriksson Linda , Vanni Simo , James Andrew C.
Published: February 2016

Despite evoked potentials' (EP) ubiquity in research and clinical medicine, insights are limited to gross brain dynamics as it remains challenging to map surface potentials to their sources in specific cortical regions. Multiple sources cancellation due to cortical folding and cross‐talk obscures close sources, e.g. between visual areas V1 and V2. Recently retinotopic functional magnetic resonance imaging (fMRI) responses were used to constrain source locations to assist separating close sources and to determine cortical current generators. However, an fMRI is largely infeasible for routine EP investigation. We developed a novel method that replaces the fMRI derived retinotopic layout (RL) by an approach where the retinotopy and current estimates are generated from EEG or MEG signals and a standard clinical T1‐weighted anatomical MRI. Using the EEG‐RL, sources were localized to within 2 mm of the fMRI‐RL constrained localized sources. The EEG‐RL also produced V1 and V2 current waveforms that closely matched the fMRI‐RL's (n = 2) r(1,198) = 0.99, P < 0.0001. Applying the method to subjects without fMRI (n = 4) demonstrates it generates waveforms that agree closely with the literature. Our advance allows investigators with their current EEG or MEG systems to create a library of brain models tuned to individual subjects' cortical folding in retinotopic maps, and should be applicable to auditory and somatosensory maps. The novel method developed expands EP's ability to study specific brain areas, revitalizing this well‐worn technique. Hum Brain Mapp 37:1696–1709, 2016. © 2016 Wiley Periodicals, Inc.
Coordinate‐based (ALE) meta‐analysis of brain activation in patients with fibromyalgia
Authors: Dehghan Mahboobeh , Schmidt‐Wilcke Tobias , Pfleiderer Bettina , Eickhoff Simon B. , Petzke Frank , Harris Richard E. , Montoya Pedro , Burgmer Markus
Published: February 2016

There are an increasing number of neuroimaging studies that allow a better understanding of symptoms, neural correlates and associated conditions of fibromyalgia. However, the results of these studies are difficult to compare, as they include a heterogeneous group of patients, use different stimulation paradigms, tasks, and the statistical evaluation of neuroimaging data shows high variability. Therefore, this meta‐analytic approach aimed at evaluating potential alterations in neuronal brain activity or structure related to pain processing in fibromyalgia syndrome (FMS) patients, using quantitative coordinate‐based “activation likelihood estimation” (ALE) meta‐analysis. 37 FMS papers met the inclusion criteria for an ALE analysis (1,264 subjects, 274 activation foci). A pooled ALE analysis of different modalities of neuroimaging and additional analyses according functional and structural changes indicated differences between FMS patients and controls in the insula, amygdala, anterior/mid cingulate cortex, superior temporal gyrus, the primary and secondary somatosensory cortex, and lingual gyrus. Our analysis showed consistent results across FMS studies with potential abnormalities especially in pain‐related brain areas. Given that similar alterations have already been demonstrated in patients with other chronic pain conditions and the lack of adequate control groups of chronic pain subjects in most FMS studies, it is not clear however, whether these findings are associated with chronic pain in general or are unique features of patients with FMS. Hum Brain Mapp 37:1749–1758, 2016. © 2016 Wiley Periodicals, Inc.
Diastereoselective Synthesis and Configurational Assignment of Novel Functionalized Cyclic Sulfamidites Precursors of Cyclic Sulfamidates
Authors: Slama Soumaya , Arfaoui Youssef , Besbes Rafâa
Published: February 2016

New 3,4,5‐trisubstituted sulfamidites were prepared through cyclization of β‐amino alcohol diesters with thionyl chloride. The oxidation of these N‐alkylated sulfamidites into the corresponding sulfamidates was then performed. Interestingly, the NMR spectra of the prepared sulfamidites revealed that the ratios of the exo and endo diastereomers of these compounds were influenced by the substituents on the α‐carbon. In addition, theoretical calculations at the DFT B3LYP/6‐31G(d) level were carried and indicated that the exo‐diastereomers were more stable than the endo forms.
Structure Revision of Caesalpinistas A and B and Isolation of a New Furanoditerpenoid from the Cotyledons of Caesalpinia decapetala var. japonica
Authors: Kamikawa Sayuri , Ohta Emi , Nehira Tatsuo , Ômura Hisashi , Ohta Shinji
Published: February 2016

A known cassane‐type furanoditerpenoid, caesalpinista B (1), and a new diterpenoid, deoxycaesaljaponin A (2), were isolated from the cotyledons of Caesalpinia decapetala var. japonica. The previously reported configurational assignments of 1 and the related diterpenoid caesalpinista A (3) were revised on the basis of X‐ray crystallography and chemical conversion. The structure of 2 was elucidated by spectroscopic data and chemical conversion into 3.
A Diastereoselective Synthesis of Functionalized Tetrahydroindeno[2′,1′,3,4]pyrido[2,1‐a]isoquinolines
Authors: Manouchehri Arezoo Lazar , Mirzaei Anvar , Yavari Issa
Published: February 2016

An effective route to alkyl 9a‐(2,3‐dihydro‐1,3‐dioxo‐1H‐inden‐2‐yl)‐9a,14,14a,14b‐tetrahydro‐14‐oxoindeno[2′,1′:3,4]pyrido[2,1‐a]isoquinoline‐9‐carboxylates via a diastereoselective one‐pot four‐component reaction of isoquinoline and alkyl prop‐2‐ynoates with two equivalents of indane‐1,3‐dione, in aqueous MeOH at room temperature, is described.
New Cytotoxic Meroterpenoids from the Plant Endophytic Fungus Pestalotiopsis fici
Authors: Wang Bo , Zhang Zhuowei , Guo Liangdong , Liu Ling
Published: February 2016

Pestalofones I – K (1–3), three new dimeric meroterpenoids with 2‐(7‐benzoyl‐2,3‐dihydrobenzofuran‐2‐yl)‐1‐phenylethan‐1‐one (in 1) and 2‐(7‐benzoyl‐2,3‐dihydrobenzofuran‐2‐yl)‐1‐(3,8‐dioxatricyclo[5.1.0.02,4]oct‐4‐yl)ethan‐1‐one (in 2 and 3) skeletons, were isolated from the solid cultures of the plant endophytic fungus Pestalotiopsis fici. The structures of 1–3 were elucidated by NMR experiments. Compound 1 was found to be present as a racemic mixture. The absolute configurations of 2 and 3 were deduced by analogy to the previously isolated metabolites pestalofones G and H (4 and 5) from the same fungus. Biogenetically, compounds 1–3 are derived from the same precursors (co‐isolated compounds 9 and 10) as the previously isolated compounds 4–8. Compounds 2 and 3 showed weak cytotoxic activities against four human tumor cell lines T24, HeLa, A549, and MCF‐7.
Molecular Cloning and Expression Determination of p38 MAPK from the Liver and Kidney of Silver Carp
Authors: Li Xiaoyu , Ma Junguo , Li Yuanyuan
Published: February 2016

The sequence of p38MAPK in silver carp (Hm‐p38a) was cloned and sequenced. Additionally, the acute toxicity of crude microcystins (MCs) on silver carp and induction expression of Hm‐p38a by MCs exposure were also determined in this study. The results reveal that the length of Hm‐p38a is 2418 bp and it contains a 1086 bp open reading frame. Hm‐p38a could encode 361 amino acids. Sequence analysis indicates that Hm‐p38a contains the conserved structures of Thr‐Gly‐Tyr motif and substrate binding site Ala‐Thr‐Arg‐Trp, and it is highly conserved in fish. Phylogenetic analysis reveals that Hm‐p38a is more closely related to fish than mammals and it belongs to p38α subfamily. Moreover, Hm‐p38a in silver carp is constitutively expressed in all examined tissues. In addition, our results indicate that MCs exposure significantly promotes the transcription of Hm‐p38a in fish liver or kidney, suggesting that mitogen‐activated protein kinase should also be the signal pathway of MCs hepatotoxicity in fish.
Phosphorylation Regulates Functions of ZEB1 Transcription Factor
Authors: Llorens M. Candelaria , Lorenzatti Guadalupe , Cavallo Natalia L. , Vaglienti Maria V. , Perrone Ana P. , Carenbauer Anne L. , Darling Douglas S. , Cabanillas Ana M.
Published: February 2016

ZEB1 transcription factor is important in both development and disease, including many TGFβ‐induced responses, and the epithelial‐to‐mesenchymal transition (EMT) by which many tumors undergo metastasis. ZEB1 is differentially phosphorylated in different cell types; however the role of phosphorylation in ZEB1 activity is unknown. Luciferase reporter studies and electrophoresis mobility shift assays (EMSA) show that a decrease in phosphorylation of ZEB1 increases both DNA‐binding and transcriptional repression of ZEB1 target genes. Functional analysis of ZEB1 phosphorylation site mutants near the second zinc finger domain (termed ZD2) show that increased phosphorylation (due to either PMA plus ionomycin, or IGF‐1) can inhibit transcriptional repression by either a ZEB1‐ZD2 domain clone, or full‐length ZEB1. This approach identifies phosphosites that have a substantial effect regulating the transcriptional and DNA‐binding activity of ZEB1. Immunoprecipitation with anti‐ZEB1 antibodies followed by western analysis with a phospho‐Threonine‐Proline‐specific antibody indicates that the ERK consensus site at Thr‐867 is phosphorylated in ZEB1. In addition to disrupting in vitro DNA‐binding measured by EMSA, IGF‐1‐induced MEK/ERK phosphorylation is sufficient to disrupt nuclear localization of GFP‐ZEB1 fusion clones. These data suggest that phosphorylation of ZEB1 integrates TGFβ signaling with other signaling pathways such as IGF‐1. J. Cell. Physiol. 231: 2205–2217, 2016. © 2016 Wiley Periodicals, Inc.
High‐efficient xylitol production by evolved Candida maltosa adapted to corncob hemicellulosic hydrolysate
Authors: Jiang Xiaolong , He Peng , Qi Xianni , Lin Yuping , Zhang Yongkui , Wang Qinhong
Published: February 2016

BACKGROUND

To compete with chemical hydrogenation, xylitol production by a biotechnological method has to decrease production cost by improving the performance of the strain, using low‐cost substrate and developing a simple and efficient bioprocess. This study attempted to reach high‐efficient xylitol production using cheap substrate.

RESULTS

A new evolved strain, Candida maltosa CHH65 showed improved cell growth in corncob hemicellulosic hydrolyzate (CHH) and similar product performance using xylose and CHH as substrate, was developed by serial culture transfer for adapting to CHH and solving the problem of inhibition of CHH. The new strain was recycled at least four times and still produced xylitol. In the test conditions, xylitol concentration reached more than 100 g L−1 within 48 h, with yield > 0.73 g g−1, and productivity > 2 g L−1 h−1 when using CHH as substrate.

CONCLUSION

The capability of the xylose‐fermenting C. maltosa to convert CHH to xylitol was greatly enhanced so that the newly developed bioprocess for xylitol production from low‐cost substrate with multiple recycled C. maltosa could be suitable for industrial application and reduce the production cost. © 2016 Society of Chemical Industry
Calmodulin activity regulates group I metabotropic glutamate receptor‐mediated signal transduction and synaptic depression
Authors: Sethna Ferzin , Zhang Ming , Kaphzan Hanoch , Klann Eric , Autio Dawn , Cox Charles L. , Wang Hongbing
Published: February 2016

Group I metabotropic glutamate receptors (mGluR), including mGluR1 and mGluR 5 (mGluR1/5), are coupled to Gq and modulate activity‐dependent synaptic plasticity. Direct activation of mGluR1/5 causes protein translation‐dependent long‐term depression (LTD). Although it has been established that intracellular Ca2+ and the Gq‐regulated signaling molecules are required for mGluR1/5 LTD, whether and how Ca2+ regulates Gq signaling and upregulation of protein expression remain unknown. Through pharmacological inhibition, we tested the function of the Ca2+ sensor calmodulin (CaM) in intracellular signaling triggered by the activation of mGluR1/5. CaM inhibitor N‐[4‐aminobutyl]‐5‐chloro‐2‐naphthalenesulfonamide hydrochloride (W13) suppressed the mGluR1/5‐stimulated activation of extracellular signal‐regulated kinase 1/2 (ERK1/2) and p70‐S6 kinase 1 (S6K1) in hippocampal neurons. W13 also blocked the mGluR1/5 agonist‐induced synaptic depression in hippocampal slices and in anesthetized mice. Consistent with the function of CaM, inhibiting the downstream targets Ca2+/CaM‐dependent protein kinases (CaMK) blocked ERK1/2 and S6K1 activation. Furthermore, disruption of the CaM–CaMK–ERK1/2 signaling cascade suppressed the mGluR1/5‐stimulated upregulation of Arc expression. Altogether, our data suggest CaM as a new Gq signaling component for coupling Ca2+ and protein upregulation and regulating mGluR1/5‐mediated synaptic modification. © 2016 Wiley Periodicals, Inc.
Studying the features of 57 confirmed CRISPR loci in 29 strains of Escherichia coli
Authors: Rahmatabadi Seyyed Soheil , Nezafat Navid , Negahdaripour Manica , Hajighahramani Nasim , Morowvat Mohammad Hossein , Ghasemi Younes
Published: February 2016

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) system is a novel type of innate defense system in prokaryotes for destruction of exogenous elements. To gain further insight into behavior and organization of the system, the extensive analysis of the available sequenced genomes is necessary. The dynamic nature of CRISPR loci is possibly valuable for typing and relative analyses of strains and microbial population. There are a few orderly bioinformatics investigations about the structure of CRISPR sequences in the Escherichia coli strains. In this study, 57 CRISPR loci were selected from 32 Escherichia coli strains to investigate their structural characteristics and potential functions using bioinformatics tools. Our results showed that most strains contained several loci that mainly included conserved direct repeats, while the spacers were highly variable. Moreover, RNA analysis of the sequences indicated that all loci could form stable RNA secondary structures and showed homology mostly with phages compared to plasmids. Only three strains included cas genes around their loci.
Phosphorus adsorption and desorption in undisturbed samples from subtropical soils under conventional tillage or no‐tillage
Authors: Fink Jessé R. , Inda Alberto V. , Bavaresco Jovana , Barrón Vidal , Torrent José , Bayer Cimélio
Published: February 2016

The dynamics of P in soil is greatly influenced by the adsorption of phosphate onto Fe‐oxides. Access of phosphate to the surface of these minerals depends on the degree of soil aggregation, which in turn is influenced by soil management system. The primary purpose of this work was to investigate P adsorption and desorption in undisturbed and disturbed soil samples from an Ultisol (Rhodic Paleudult) and an Oxisol (Humic Hapludox) under conventional tillage (CT) or no‐tillage (NT). Phosphorus adsorption and desorption in undisturbed soil was studied by using a continuous flux system containing a P solution for adsorption measurements or deionized water and Mehlich‐I solution for desorption measurements. The Oxisol, which had higher clay, hematite, and goethite contents than the Ultisol, exhibited the highest maximum P adsorption capacity (Pmax) values in disturbed samples. Also, the disturbed Ultisol samples had lower Pmax values under NT than under CT. The undisturbed soil samples exhibited no significant differences in P adsorption between soil management systems, but P desorption was more marked under NT than under CT. The samples of Oxisol under NT exhibited lower P adsorption rates and higher P desorption rates than the CT samples of the same soil. The decreased P adsorption in undisturbed samples relative to disturbed samples suggests that P adsorption is influenced by physical properties of soil.
Microbial biomass and soil organic carbon accumulation on a former lakebed near Novosibirsk, Russia
Authors: Yakutin Mikhail. V. , Anopchenko L. , Conen F.
Published: February 2016

Shrinking of Lake Chany in W Siberia exposed 10,000 km2 of former lakebed. On this new land we studied a chronosequence of young soils. The fraction of microbial C in total organic C had stabilized at 3% after 30 to 40 y. Concentration of organic C increased within the first 50 to 100 y to 4–5% in the first 10 cm, and to 2–3% at 10–20 cm depth. The amount of sequestered C is equivalent to about 2.5 d of current anthropogenic CO2 emissions.
Effect of preceding crop on Fusarium species and mycotoxin contamination of wheat grains
Authors: Qiu Jianbo , Dong Fei , Yu Mingzheng , Xu Jianhong , Shi Jianrong
Published: February 2016

BACKGROUND

The Fusarium graminearum species complex infects several cereals and causes the reduction of grain yield and quality. Many factors influence the extent of Fusarium infection and mycotoxin levels. Such factors include crop rotation. In the present study, we explored the effect of rice or maize as former crops on mycotoxin accumulation in wheat grains.

RESULTS

More than 97% of samples were contaminated with deoxynivalenol (DON). DON concentrations in wheat grains from rice and maize rotation fields were 884.37 and 235.78 µg kg−1. Zearalenone (ZEN) was detected in 45% of samples which were mainly collected from maize–wheat rotation systems. Fusarium strains were isolated and more F. graminearum sensu stricto (s. str.) isolates were cultured from wheat samples obtained from maize rotation fields. DON levels produced by Fusarium isolates from rice rotation fields were higher than those of samples from maize rotation fields.

CONCLUSIONS

Rice–wheat rotation favours DON accumulation, while more ZEN contamination may occur in maize–wheat rotation models. Appropriate crop rotation may help to reduce toxin levels in wheat grains. © 2016 Society of Chemical Industry
Design and performance evaluation of a mesocosm facility and techniques to simulate ocean acidification and warming
Authors: Falkenberg Laura J. , Russell Bayden D. , Connell Sean D.
Published: February 2016

Forecasting the ecological consequences of a changing climate requires a range of approaches, including the use of mesocosms in which multiple physical and chemical parameters can be manipulated and the response of interacting organisms quantified. Here, we describe the design and evaluate the performance of a facility incorporating large mesocosms that can contain diverse biological assemblages within which CO2 and temperature can be manipulated. The key infrastructure is: 15 covered mesocosms each with a maximum water volume of 2300 L, a gas mixer containing two mass flow controllers to produce CO2‐enriched air and an individual heater/chiller unit for each treatment mesocosm to independently regulate temperature. Our results report an initial proof‐of‐concept experiment (total of 100 d duration) in which we constructed communities of biota that characterise temperate Australian kelp forests (i.e., kelp, their key competitors and herbivores) and then undertook procedures designed to reproduce CO2 and temperature conditions forecasted for the year 2100 (target differences in midday means: 0.15 pH units, 2.5°C). The system achieved the intended environmental conditions, with CO2 and temperature in treatment enclosures consistently different from the controls (mean midday treatment effect ± SE; 0.15 ± 0.01 pH units and 2.6 ± 0.1°C, respectively), yet still tracking their diurnal fluctuations. The reliability of the facility over the experimental period indicates it is a robust and accurate tool that can mimic intended scenarios of CO2 and temperature change, facilitating the study of the influence of these factors on marine organisms and their interactions.
Thermoreversible Order−Order Transition of a Triblock Copolymer Containing a Mesogen‐Jacketed Liquid Crystalline Polymer with a Re‐Entrant Phase Behavior
Authors: Pan Yu , Shi Ling‐Ying , Ping Jing , Zhang Zhenyu , Gu Kehua , Fan Xing‐He , Shen Zhihao
Published: February 2016

Poly{2,5‐bis[(4‐butoxyphenyl)‐oxycarbonyl]styrene} (PBPCS) with a re‐entrant phase behavior is used to synthesize a new kind of ABC triblock copolymers (triBCPs), poly(dimethylsiloxane)‐b‐polystyrene‐b‐PBPCS (PDMS‐b‐PS‐b‐PBPCS, DSB). Two well‐defined triBCPs D120S100B50 and D120S100B120 with different molecular weights (MWs) and narrow MW distributions are synthesized by sequential atom transfer radical polymerization. The volume fractions of PDMS, PS, and PBPCS in D120S100B50 are 0.24, 0.26, and 0.50, respectively, while the values in D120S100B120 are 0.14, 0.16, and 0.70, respectively. At low temperatures, PBPCS is amorphous. Both samples form a core–shell hexagonally packed cylindrical (CSH) morphology. At high temperatures, PBPCS in the triBCPs can form a liquid crystalline (LC) phase, the transformation of which can induce an order−order transition (OOT) of D120S100B120. The nanostructure changes from a CSH structure to a three‐phase‐four‐layer lamellar structure, and the transition is thermoreversible. The sequence of the OOT is opposite to that of a coil−coil−coil triBCP. The unusual LC behavior of PBPCS plays an important role on the thermoreversible morphological transition of the triBCP.

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Recent Progress on the Design and Applications of Polysaccharide‐Based Graft Copolymer Hydrogels as Adsorbents for Wastewater Purification
Authors: Mittal Hemant , Ray Suprakas Sinha , Okamoto Masami
Published: February 2016

Gum polysaccharides are one of the most abundant bio‐based polymers. They are generally derived from plants as exudates or from microorganisms and have diverse applications in many industries, especially in the food industries where they are used as emulsifiers and thickeners. In their natural form, gum polysaccharides have poor mechanical and physical properties; therefore, they are frequently modified with various synthetic monomers such as acrylamide and acrylic acid using graft copolymerization. Graft copolymerization is one of the most trusted and widely used synthetic methods for the modification of gum polysaccharides. Gum polysaccharides modified in this way have improved mechanical and physicochemical properties. Furthermore, gum polysaccharides contain a variety of functional groups, for example, carboxylic acid and hydroxyl groups; therefore, they have been used extensively as adsorbents for the removal of different impurities from wastewater such as toxic heavy metal cations and synthetic dyes. Here, the chemical and physical properties of gum polysaccharides, different methods of graft copolymerization, and the use of graft copolymer gum‐polysaccharide‐based hydrogels are reviewed in detail for the removal of toxic heavy metal cations and synthetic dyes from aqueous solutions.

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Antidyskinetic effect of A2A and 5HT1A/1B receptor ligands in two animal models of Parkinson's disease
Authors: Pinna Annalisa , Ko Wai Kin D. , Costa Giulia , Tronci Elisabetta , Fidalgo Camino , Simola Nicola , Li Qin , Tabrizi Mojgan Aghazadeh , Bezard Erwan , Carta Manolo , Morelli Micaela
Published: February 2016

Background

The serotonin 5‐HT1A/1B receptor agonist eltoprazine suppressed dyskinetic‐like behavior in animal models of Parkinson's disease (PD) but simultaneously reduced levodopa (l‐dopa)–induced motility. Moreover, adenosine A2A receptor antagonists, such as preladenant, significantly increased l‐dopa efficacy in PD without exacerbating dyskinetic‐like behavior.

Objectives

We evaluated whether a combination of eltoprazine and preladenant may prevent or suppress l‐dopa–induced dyskinesia, without impairing l‐dopa's efficacy in relieving motor signs, in 2 PD models: unilateral 6‐hydroxydopamine–lesioned rats and 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)–treated monkeys.

Methods

Rotational behavior and abnormal involuntary movements, or disability and l‐dopa–induced dyskinesia were evaluated in 6‐hydroxydopamine–lesioned rats and MPTP‐treated monkeys, respectively. Moreover, in the rodent striatum, induction of immediate–early gene zif‐268, an index of long‐term changes, was correlated with dyskinesia.

Results

In 6‐hydroxydopamine–lesioned rats, combined administration of l‐dopa (4 mg/kg) plus eltoprazine (0.6 mg/kg) plus preladenant (0.3 mg/kg) significantly prevented or reduced dyskinetic‐like behavior without impairing motor activity. Zif‐268 was increased in the striatum of rats treated with l‐dopa and l‐dopa plus preladenant compared with vehicle. In contrast, rats treated with eltoprazine (with or without preladenant) had lower zif‐268 activation after chronic treatment in both the dyskinetic and l‐dopa–non‐primed groups. Moreover, acute l‐dopa plus eltoprazine plus preladenant prevented worsening of motor performance (adjusting step) and sensorimotor integration deficit. Similar results were obtained in MPTP‐treated monkeys, where a combination of preladenant with eltoprazine was found to counteract dyskinesia and maintain the full therapeutic effects of a low dose of l‐dopa.

Conclusions

Our results suggest a promising nondopaminergic pharmacological strategy for the treatment of dyskinesia in PD. © 2016 International Parkinson and Movement Disorder Society
A relaxometric method for the assessment of intestinal permeability based on the oral administration of gadolinium‐based MRI contrast agents
Authors: Gianolio Eliana , Boffa Cinzia , Orecchia Valeria , Bardini Paola , Catanzaro Valeria , Poli Valeria , Aime Silvio
Published: February 2016

Herein, a new relaxometric method for the assessment of intestinal permeability based on the oral administration of clinically approved gadolinium (Gd)‐based MRI contrast agents (CAs) is proposed. The fast, easily performed and cheap measurement of the longitudinal water proton relaxation rate (R1) in urine reports the amount of paramagnetic probe that has escaped the gastrointestinal tract. The proposed method appears to be a compelling alternative to the available methods for the assessment of intestinal permeability. The method was tested on the murine model of dextran sulfate sodium (DSS)‐induced colitis in comparison with healthy mice. Three CAs were tested, namely ProHance®, MultiHance® and Magnevist®. Urine was collected for 24 h after the oral ingestion of the Gd‐containing CA at day 3–4 (severe damage stage) and day 8–9 (recovery stage) after treatment with DSS. The Gd content in urine measured by 1H relaxometry was confirmed by inductively coupled plasma‐mass spectrometry (ICP‐MS). The extent of urinary excretion was given as a percentage of excreted Gd over the total ingested dose. The method was validated by comparing the results obtained with the established methodology based on the lactulose/mannitol and sucralose tests. For ProHance and Magnevist, the excreted amounts in the severe stage of damage were 2.5–3 times higher than in control mice. At the recovery stage, no significant differences were observed with respect to healthy mice. Overall, a very good correlation with the lactulose/mannitol and sucralose results was obtained. In the case of MultiHance, the percentage of excreted Gd complex was not significantly different from that of control mice in either the severe or recovery stages. The difference from ProHance and Magnevist was explained on the basis of the (known) partial biliary excretion of MultiHance in mice. Copyright © 2016 John Wiley & Sons, Ltd.
Investigation of relative metabolic changes in the organs and plasma of rats exposed to X‐ray radiation using HR‐MAS 1H NMR and solution 1H NMR
Authors: Jang Won Gyo , Park Ju Yeon , Lee Jueun , Bang Eunjung , Kim So Ra , Lee Eun Kyeong , Yun Hyun Jin , Kang Chang‐Mo , Hwang Geum‐Sook
Published: February 2016

Excess exposure to ionizing radiation generates reactive oxygen species and increases the cellular inflammatory response by modifying various metabolic pathways. However, an investigation of metabolic perturbations and organ‐specific responses based on the amount of radiation during the acute phase has not been conducted. In this study, high‐resolution magic‐angle‐spinning (HR‐MAS) NMR and solution NMR‐based metabolic profiling were used to investigate dose‐dependent metabolic changes in multiple organs and tissues – including the jejunum, spleen, liver, and plasma – of rats exposed to X‐ray radiation. The organs, tissues, and blood samples were obtained 24, 48, and 72 h after exposure to low‐dose (2 Gy) and high‐dose (6 Gy) X‐ray radiation and subjected to metabolite profiling and multivariate analyses. The results showed the time course of the metabolic responses, and many significant changes were detected in the high‐dose compared with the low‐dose group. Metabolites with antioxidant properties showed acute responses in the jejunum and spleen after radiation exposure. The levels of metabolites related to lipid and protein metabolism were decreased in the jejunum. In addition, amino acid levels increased consistently at all post‐irradiation time points as a consequence of activated protein breakdown. Consistent with these changes, plasma levels of tricarboxylic acid cycle intermediate metabolites decreased. The liver did not appear to undergo remarkable metabolic changes after radiation exposure. These results may provide insight into the major metabolic perturbations and mechanisms of the biological systems in response to pathophysiological damage caused by X‐ray radiation. Copyright © 2016 John Wiley & Sons, Ltd.
Effects of transcytolemmal water exchange on the assessment of myocardial extracellular volume with cardiovascular MRI
Authors: Goldfarb James W. , Zhao Wenguo
Published: February 2016

Quantitative analysis of the myocardial interstitial space is gaining increased interest as a biomarker in the MRI and clinical cardiovascular communities. To investigate the effect of water exchange on the calculation of myocardial extracellular volume (ECV), we employed two tissue models: the standard ECV two‐point model (SM) and the shutter speed model (SSM). Twenty individuals (18 men and two women; age 61.9 ± 10.3 years) underwent MRI at 1.5 T with pre‐contrast and post‐contrast dynamic T1 quantification. Means, standard deviations and ranges for SM and SSM model parameters were calculated. Infarct and viable myocardial model parameters as well as apparent ECV values calculated with the SM and SSM were statistically compared. Viable ECVSM remained temporally constant (27.3–28.0%: P = 0.5) and infarcted myocardial ECVSM changed significantly (49.3–58.8%; P < 0.001), reaching a steady‐state value after 15 min. The intracellular lifetime of water was three times greater in infarcted myocardium when compared with viable myocardium (τi: 66.6 ± 115 versus 208.7 ± 72.7 ms) and accompanied a twofold increase in ECV (ECVSSM: 30.3 ± 11.1 versus 71.0 ± 13.1%; P < 0.001). There was a consistent significant difference in ECV values of infarcted myocardium at different timepoints between the SM and SSM, but not viable myocardium, presumably due to slower water exchange. In summary, we found a significant change in apparent ECV and water exchange in infarcted myocardium when compared with viable myocardium. This was visualized by changes in dynamic contrast enhanced curve shapes and quantified using the SSM as not only an increase in apparent ECV but also a decrease in water exchange. Copyright © 2016 John Wiley & Sons, Ltd.
Vibrational behavior of non‐uniform piezoelectric sandwich beams made of CNT‐reinforced polymer nanocomposite by considering the agglomeration effect of CNTs
Authors: Kamarian S. , Bodaghi M. , Pourasghar A. , Talebi S.
Published: February 2016

The present work deals with natural frequency analysis of non‐uniform nanocomposite beams with surface‐bonded piezoelectric layers by considering the agglomeration effect of Carbon Nanotubes (CNTs). The material properties of the nanocomposite beam are predicted employing Eshelby–Mori–Tanaka approach based on an equivalent fiber and compared with available experimental data in the literature. The equation of motion is derived employing Hamilton's principle and Generalized Differential Quadrature technique as an efficient and accurate numerical tool is employed for free vibration analysis of the structures. Detailed parametric studies are carried out to examine influences of CNTs volume fraction, CNTs agglomeration, thickness of piezoelectric layers, piezoelectric constant, dielectric constant, boundary conditions etc., on the behavior of freely vibrating smart structure. Results represent that for some cases, consideration of agglomeration effect of CNTs is not required while for some other cases it has a significant role on the response. The numerical results also reveal that using thick piezoelectric layer does not necessarily improve the natural frequency of the structure. POLYM. COMPOS., 38:E553–E562, 2017. © 2016 Society of Plastics Engineers
A high‐level theoretical study into the atmospheric phase hydration, bond dissociation enthalpies, and acidity of aldehydes
Authors: Rayne Sierra , Forest Kaya
Published: February 2016

CBS‐Q//B3, G4(MP2), and G4 composite method calculations were used to estimate atmospheric phase standard state (298.15 K, 1 atm) free energies of hydration (ΔhydrG°(g)), hydration equilibrium constants (log Khydr,(g)), bond dissociation enthalpies (BDEs), and enthalpies (ΔdH°(g)) and free energies (ΔdG°(g)) of aldehydic proton acid dissociation for various substituted aldehydes with electron withdrawing and electron releasing groups. Good quality log Khydr,(g) correlations with the Swain–Lupton resonance effect parameters R and R+ were found, allowing extension of the model to predict log Khydr,(g) values for 487 substituted aldehydes having available R‐values and 108 substituted aldehydes having available R+ values. Good correlations were also found between experimental aqueous phase hydration equilibrium constants (log Khydr,(aq)) and summative R/R+ values for peripheral substituents on a range of carbonyl derivatives (aldehydes, ketones, esters, and amides), suggesting that the structure–reactivity modeling approach can be extended to include all possible combinations of R1C(O)R2 carbonyl substitution in both gas and aqueous systems. Computationally derived BDEs and ΔdH°(g)/ΔdG°(g) were in good agreement with the limited experimental and theoretical datasets. BDEs did not generally correlate with any of the Hammett substituent constants or Swain–Lupton parameters considered. Gas phase acidities exhibited high correlation coefficients with Hammett inductive substituent constants (σI) and field effect parameters (F), allowing these to be employed as surrogates for estimating the gas phase aldehydic proton acidities of a larger potential compound range. The resulting models will be of use in predicting the environmental behavior for a broad range of environmentally relevant compounds containing carbonyl functionalities. Copyright © 2016 John Wiley & Sons, Ltd.
Crystal structure of translation initiation factor 5B from the crenarchaeon Aeropyrum pernix
Authors: Murakami Ryo , Miyoshi Tomohiro , Uchiumi Toshio , Ito Kosuke
Published: February 2016

Initiation factor 5B (IF5B) is a universally conserved translational GTPase that catalyzes ribosomal subunit joining. In eukaryotes, IF5B directly interacts via a groove in its domain IV with initiation factor 1A (IF1A), another universally conserved initiation factor, to accomplish efficient subunit joining. Here, we have determined the first structure of a crenarchaeal IF5B, which revealed that the archaea‐specific region of IF5B (helix α15) binds and occludes the groove of domain IV. Therefore, archaeal IF5B cannot access IF1A in the same manner as eukaryotic IF5B. This fact suggests that different relationships between IF5B and IF1A exist in archaea and eukaryotes. Proteins 2016; 84:712–717. © 2016 Wiley Periodicals, Inc.
A hidden aggregation‐prone structure in the heart of hypoxia inducible factor prolyl hydroxylase
Authors: Hadi‐Alijanvand Hamid , Proctor Elizabeth A. , Ding Feng , Dokholyan Nikolay V. , Moosavi‐Movahedi Ali A.
Published: February 2016

Prolyl hydroxylase domain‐containing protein 2 (PHD2), as one of the most important regulators of angiogenesis and metastasis of cancer cells, is a promising target for cancer therapy drug design. Progressive studies imply that abnormality in PHD2 function may be due to misfolding. Therefore, study of the PHD2 unfolding pathway paves the way for a better understanding of the influence of PHD2 mutations and cancer cell metabolites on the protein folding pathway. We study the unfolding of the PHD2 catalytic domain using differential scanning calorimetry (DSC), fluorescence spectroscopy, and discrete molecular dynamics simulations (DMD). Using computational and experimental techniques, we find that PHD2 undergoes four transitions along the thermal unfolding pathway. To illustrate PHD2 unfolding events in atomic detail, we utilize DMD simulations. Analysis of computational results indicates an intermediate species in the PHD2 unfolding pathway that may enhance aggregation propensity, explaining mutation‐independent PHD2 malfunction. Proteins 2016; 84:611–623. © 2016 Wiley Periodicals, Inc.
Effects of surface morphology and C concentration in C‐doped GaN buffer on breakdown voltage of AlGaN/GaN HEMTs on free‐standing GaN substrate
Authors: Tanabe Shinichi , Watanabe Noriyuki , Uchida Masahiro , Matsuzaki Hideaki
Published: February 2016

We report on the validity of using a C‐doped GaN buffer to achieve high‐breakdown‐voltage AlGaN/GaN high‐electron mobility transistors (HEMTs) on conductive free‐standing GaN substrates. We use trimethygallium to dope C into the buffer. We show that breakdown voltage depends not only on the C concentration of the buffer but also on the surface morphology of the HEMT structure. We demonstrate off‐state breakdown voltage of over 2 kV by controlling the C concentration of the buffer, thickness of the buffer, and the surface morphology.
Probing the localization of charge and the extent of disorder through electronic transport on Au nanoparticle–copper phthalocyanine multijunction networks
Authors: Balliou Angelika , Kazim Samrana , Pfleger Jiří , Rakušan Jan , Skoulatakis George , Kennou Stella , Glezos Nikos
Published: February 2016

Precision control of charge transport can provide a solid basis for the design of materials with novel properties. We report on the bottom‐up fabrication and study of the electronic properties of molecular multijunction networks comprising ultrafine gold nanoparticles (AuNPs) of diameter ∼1.4 nm, electronically linked by means of copper 3‐diethylamino‐1‐propylsulfonamide sulfonic acid‐substituted phthalocyanine (CuPcSu) molecules. When electrons flow through the nonlinked nanoparticle arrays, they experience onsite Coulomb repulsion and are strongly localized, with a localization length ξ = 0.7 nm. Under dynamic excitation the system functions as a single electron‐transport regulator, undergoing Coulomb oscillations, whereas the introduction of CuPcSu molecules results in the formation of a network of multiple molecular/Au nanojunctions and conductance increases by five orders of magnitude. This switching behavior functions on reversible redox reactions and pushes carriers into a state of weaker localization. In this state, electrons spread over several junctions and all temperature‐scaled current versus voltage curves, J/T1 + α versus eV/kT, collapse into one universal curve, characterizing the network and the extent of its disorder. Utilizing this property, we demonstrate the effect of interelectrode distance on the conduction nodes' topological disorder. The system consists a promising candidate for Au NPs‐based thin films with tunable properties wherever solution‐based fabrication methods, such as injection printing, are envisioned.
Nanoconstrictions for investigating spin transfer torque effect in granular Ag–Co films
Authors: Paddubrouskaya H. , Volodin A. , Petermann C. , Tripathi S. , Lagae L. , Temst K. , Van Haesendonck C.
Published: February 2016

We used lithographically fabricated nanoconstrictions made of Ag–Co granular thin films to achieve current densities above 10 A/cm during magnetotransport measurements. Systematically measured variations of the resistance with current under high applied magnetic fields did not reveal any dramatically large magnetoresistance effect, in contrast to the previous observations using mechanical point contact based techniques. Our experimental results on resistance switching by current injection in the Ag–Co nanoconstrictions reveal spin torque effects. The switching amplitudes are considerably smaller when compared to the results obtained for pillar shaped trilayers due to the large number of Co grains in the nanoconstrictions. We demonstrate that the use of point contact patterns with nanometer dimensions, where effects resulting from current induced mechanical distortions at high magnetic fields are negligible, has obvious advantages over the mechanical point contact technique for studying spin injection effects.