bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

ABSTRACTBACKGROUNDTo 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.RESULTSA 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.CONCLUSIONThe 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
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

AbstractThe 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

AbstractShrinking 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

AbstractBACKGROUNDThe 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.RESULTSMore 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.CONCLUSIONSRice–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

AbstractForecasting 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

AbstractBackgroundThe 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.ObjectivesWe 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.MethodsRotational 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.ResultsIn 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.ConclusionsOur results suggest a promising nondopaminergic pharmacological strategy for the treatment of dyskinesia in PD. © 2016 International Parkinson and Movement Disorder Society
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.
Crystal structure of translation initiation factor 5B from the crenarchaeon Aeropyrum pernix
Authors: Murakami Ryo , Miyoshi Tomohiro , Uchiumi Toshio , Ito Kosuke 
Published: February 2016

ABSTRACTInitiation 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

ABSTRACTProlyl 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.
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

AbstractWe 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.
An online method for the analysis of volatile organic compounds in electronic cigarette aerosol based on proton transfer reaction mass spectrometry
Authors: Breiev Kostiantyn , Burseg Kerstin M. M. , O'Connell Grant , Hartungen Eugen , Biel Stefan S. , Cahours Xavier , Colard Stéphane , Märk Tilmann D. , Sulzer Philipp 
Published: February 2016

RationaleDue to the recent rapid increase in electronic cigarette (e‐cigarette) use worldwide, there is a strong scientific but also practical interest in analyzing e‐cigarette aerosols. Most studies to date have used standardized but time‐consuming offline technologies. Here a proof‐of‐concept for a fast online quantification setup based on proton transfer reaction mass spectrometry (PTR‐MS) is presented.MethodsThe combination of a novel sampling interface with a time‐of‐flight PTR‐MS instrument specially designed for three scenarios is introduced: (i) mainstream aerosol analysis (aerosol that the user inhales prior to exhalation), and analysis of exhaled breath following (ii) mouth‐hold (no inhalation) and (iii) inhalation of e‐cigarette aerosols. A double‐stage dilution setup allows the various concentration ranges in these scenarios to be accessed.ResultsFirst, the instrument is calibrated for the three principal constituents of the e‐cigarettes' liquids, namely propylene glycol, vegetable glycerol and nicotine. With the double‐stage dilution the instrument's dynamic range was easily adapted to cover the concentration ranges obtained in the three scenarios: 20–1100 ppmv for the mainstream aerosol characterisation; 4–300 ppmv for the mouth‐hold; and 2 ppbv to 20 ppmv for the inhalation experiment.ConclusionsIt is demonstrated that the novel setup enables fast, high time resolution e‐cigarette studies with online quantification. This enables the analysis and understanding of any puff‐by‐puff variations in e‐cigarette aerosols. Large‐scale studies involving a high number of volunteers will benefit from considerably higher sample throughput and shorter data processing times. © 2016 The Authors. Rapid Communications in Mass Spectrometry Published by John Wiley & Sons Ltd.
Differentiation of cyclic tertiary amine cathinone derivatives by product ion electron ionization mass spectrometry
Authors: Abiedalla Younis , Abdel‐Hay Karim , DeRuiter Jack , Randall Clark C. 
Published: February 2016

RationaleA number of synthetic cathinones (aminoketones, 'bath salts') are tertiary amines containing a cyclic amino group, most commonly pyrrolidine. These totally synthetic compounds can be prepared in a number of regioisomeric designer modifications and many of these can yield isomeric major fragment ions in electron ionization mass spectrometry (EI‐MS).MethodsA series of regioisomeric cyclic tertiary amines were prepared and evaluated in EI‐MS and MS/MS product ion experiments. The cyclic amines azetidine, pyrrolidine, piperidine and azepane were incorporated into a series of aminoketones related to the cathinone derivative drug of abuse known as MDPV. Deuterium labeling in both the cyclic amine and alkyl side chain allowed for the confirmation of the structure for the major product ions formed from the EI‐MS iminium cation base peaks.ResultsThese iminium cation base peaks show characteristic product ion spectra which allow differentiation of the ring and side‐chain portions of the structure. The small alkyl side chains favor ring fragmentation in the formation of the major product ions. The higher side‐chain homologues appear to promote product ion formation by side‐chain fragmentation. Both side‐chain and ring fragmentation yield a mixture of product ions in the piperidine and azepane series.ConclusionsProduct ion fragmentation provides useful data for differentiation of cyclic tertiary amine iminium cations from cathinone derivative drugs of abuse. Regioisomeric iminium cations of equal mass yield characteristic product ions for the alkyl side‐chain homologues of azetidine, pyrrolidine, piperidine and azepane cyclic amines. Copyright © 2016 John Wiley & Sons, Ltd.
Polyalanine – a practical polypeptide mass calibration standard for matrix‐assisted laser desorption/ionization mass spectrometry and tandem mass spectrometry in positive and negative mode
Authors: Gruendling Till , Sauerland Volker , Barahona César , Herz Corinna , Nitsch Ute 
Published: February 2016

RationaleMass calibration in matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) is currently obtained using mixtures of individual peptides. This procedure has several drawbacks, including laborious preparation, limited shelf life and unequal calibration mass spacing. Polyalanine, a simple to prepare polydisperse molar mass standard, alleviates these problems.MethodsPolyalanine is prepared by the typical protocols for biological sample analytics.ResultsPolyalanine is the first polymeric standard providing abundant signals in both, positive and negative polarity mode with the typical matrices DHB and HCCA.ConclusionsFacile MS as well as MS/MS calibration is thus enabled for the first time in both polarity modes by employing this polydisperse standard. Copyright © 2016 John Wiley & Sons, Ltd.