bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Iron in Spinach Using Linear Sweep Voltammetry at Iodine-Coated Platinum Rotating Disk Electrode
Authors: Amayreh Mohammad , Hourani Mohammed Khair 
Published: November 2018

Abstract
Background: In contrast to the hyper-reactive platinum electrode, iodine-coated platinum electrode shows remarkable inertness toward adsorption and surface processes. For this reason, iodine-coated platinum electrode lends itself to interesting voltammetric applications. Hydrodynamic voltammetric analysis, one of the voltammetric techniques family, has many advantages over stationary voltammetric techniques inter aliathe steady state current and the higher sensitivity. Objective: The present work is aimed at utilization of iodine-coated platinum rotating disk electrode for analysis of iron in spinach.Methods: The developed method is based on a voltammetric sweep at an iodine-coated rotating-disk platinum electrode. The optimized experimental parameters included a potential scan from –0.20 to 0.85 V versus Ag/AgCl/[Cl-] = 1.0 M, 50 mV/s scan rate, and a rotation rate of 1000 rpm. Results: Oxidation of iron at the iodine-coated platinum rotating disk electrode was manifested by a wave at E1/2 = +0.72 V. The limiting current was found to exhibit an excellent linearity with the concentration of iron (R2 = 0.996). The detection limit was 0.0 7 ppm. A comparative analytical study on determination of iron content in spinach samples was conducted by the voltammetric method and ICP-OES method. Application of the paired t-test to the results indicated that the null hypothesis is valid at P = 0.05. Conclusions: A sensitive and selective validated method was developed for determination of iron content in spinach. Highlights: A simple, fast, and reliable voltammetric methodwas developed for iron analysis in spinach. The main feature of the developed method is removing the effect of cationic interferences.
Activating Open Science Communities in Göttingen: From Policies to Real Meet-Ups
Authors: Schmidt Birgit 
Published: November 2018

Watch the VIDEO.Over the last two decades several research institutions have created policies which target Open Access to publications and research data, and are now moving on to Open Science from a wider perspective. These policies formulate an ambition with references to reality. This reality might look good on paper however, the challenge is to make this vision work at the individual and research group level.One way to bring these visions forward is to activate and grow a network of institutional Open Science practitioners and enthusiasts – by involving researchers, librarians, research managers/administrators and others, and creating opportunities for exchange and collaboration. In particular early career researchers will have very concrete ideas on what works for them, what is missing and what their challenges are when stepping into Open Science practices. The University of Göttingen is committed to make research results accessible and reusable for academia and the wider society. Its revised OA policy dates from 2016 (the first version dates from 2005) and the research data policy from 2014 [1].These policies serve as a reference point for desired practices as well as existing and emerging service areas. However, often these policies may not play an explicit role in researchers’ day-to-day practices – some elements may already be part of “normal science” while others have not been fully implemented yet.The presentation will focus on the practical vision and establishment of the Göttingen Open Science Meet-ups [2], as well as experiences and lessons learned from nearly two years of operation (at the time of the Munin conference). The initiative was launched in Autumn 2016 by a group of librarians. We will elaborate on how we reach out to and work with early career researchers, and what types of meetings are requested, e.g. informal technology-focused meetings (Hacky Hour Göttingen [3]). Moreover, we will provide some insight into how the sessions facilitate learning together and from each other (both in terms of topics as well as mind sets). From the library perspective there are also opportunities to link Open Science learning to service areas, in particular where new demands emerge, and to make existing services better known.Last, but not least, the Open Science network facilitated by these meet-ups provides opportunities to better link institutional policies with researchers’ practices – in particular, through discussions on opportunities and how to overcome obstacles as well as how to increase benefits and incentives. To this end, although the meet-ups mainly aim at strengthening a bottom-up approach, they also provide opportunities to inspire next steps for Open Science from a leadership perspective and to lift emerging good practices to a higher level.
De novo annotation of the transcriptome of the Northern Wheatear (Oenanthe oenanthe)
Authors: Frias-Soler Roberto Carlos , Villarín Pildaín Lilian , Hotz-Wagenblatt Agnes , Kolibius Jonas , Bairlein Franz , Wink Michael 
Published: November 2018

We have sequenced a partial transcriptome of the Northern Wheatear (Oenanthe oenanthe), a species with one of the longest migrations on Earth. The transcriptome was constructed de novo using RNA-Seq sequence data from the pooled mRNA of six different tissues: brain, muscle, intestine, liver, adipose tissue and skin. The samples came from nine captive-bred wheatears collected at three different stages of the endogenous autumn migratory period: (1) lean birds prior the onset of migration, (2) during the fattening stage and (3) individuals at their migratory body mass plateau, when they have almost doubled their lean body mass. The sample structure used to build up the transcriptome of the Northern Wheatears concerning tissue composition and time guarantees the future survey of the regulatory genes involved in the development of the migratory phenotype. Through the pre-migratory period, birds accomplish outstanding physical and behavioural changes that involve all organ systems. Nevertheless, the molecular mechanisms through which birds synchronize and control hyperphagia, fattening, restlessness increase, immunity boosting and tuning the muscles for such endurance flight are still largely unknown. The use of RNA-Seq has emerged as a powerful tool to analyse complex traits on a broad scale, and we believe it can help to characterize the migratory phenotype of wheatears at an unprecedented level. The primary challenge to conduct quantitative transcriptomic studies in non-model species is the availability of a reference transcriptome, which we have constructed and described in this paper. The cDNA was sequenced by pyrosequencing using the Genome Sequencer Roche GS FLX System; with single paired-end reads of about 400 bp. We estimate the total number of genes at 15,640, of which 67% could be annotated using Turkey and Zebra Finch genomes, or protein sequence information from SwissProt and NCBI databases. With our study, we have made a first step towards understanding the migratory phenotype regarding gene expression of a species that has become a model to study birds long-distance migrations.
Rational Design of Porous Nanofiber Adsorbent by Blow‐Spinning with Ultrahigh Uranium Recovery Capacity from Seawater
Authors: Yuan Yihui , Zhao Shilei , Wen Jun , Wang Dong , Guo Xiwei , Xu Liangliang , Wang Xiaolin , Wang Ning 
Published: November 2018

AbstractHighly efficient recovery of uranium from seawater is of great concern because of the growing demand for nuclear energy. The use of amidoxime‐based polymeric fiber adsorbents is considered to be a promising approach because of their relatively high specificity and affinity to uranyl. The surface area, hydrophility, and surface charge of the adsorbent are reported to be critical factors that influence uranium recovery efficiency. Here, a porous amidoxime‐based nanofiber adsorbent (SMON–PAO) that exhibits the highest uranium recovery capacity among the existing fiber adsorbents both in 8 ppm uranium spiked seawater (1089.36 ± 64.31 mg‐U per g‐Ads) and in natural seawater (9.59 ± 0.64 mg‐U per g‐Ads) is prepared by blow spinning. These nanofibers are obtained by compositing polyacrylamidoxime with montmorillonite and exhibit the increased surface area and more exposed functional amidoxime moieties for uranyl adsorption. The residual montmorillonite enhances the hydrophility and reduces the negative surface charge, thereby increasing the contact of the adsorbent with seawater and reducing the charge repulsion between negative amidoxime group and negative uranyl species ([UO2(CO3)3]4−). The finding of this study indicates that rational design of uranium recovery adsorbents by comprehensive utilizing the key factors that influence uranium recovery performance is a promising approach for developing economically feasible uranium recovery materials.
Creep life assessment craze damage evolution of polyethylene methacrylate
Authors: Gao Zongzhan , Liu Wei , Li QingHai , Yue ZhuFeng 
Published: November 2018

AbstractTests have been conducted to investigate the influence of temperature, stress, and crazing for polyethylene methacrylate (PMMA) creep life. Creep life decreases with stress in a logarithmic relation, and rupture strains increase with decreasing stress. To assess the creep life of PMMA, the Larson–Miller parameter is first introduced to correlate stress and temperature with rupture time. The important role of crazing in polymer material damage, especially, the craze density and craze growth rate in the stable creep stage, is demonstrated. The craze initiation time is related to the tensile strength and to the stress and temperature at the elastic limit, and the craze initiation time can be predicted by an empirical model subsequently presented in this paper. Based on the connection between craze growth and creep rupture time, thereafter, a modified Monkman–Grant model is presented to predict creep life. The curve of craze density over creep time has the same two distinct stages as the curve of strain over time. In the final sections, a critical assessment of creep damage is also presented to provide a convenient method to predict residual life using only craze density.
Slippery Surface Based on Photoelectric Responsive Nanoporous Composites with Optimal Wettability Region for Droplets' Multifunctional Manipulation
Authors: Han Keyu , Heng Liping , Zhang Yuqi , Liu Yao , Jiang Lei 
Published: November 2018

AbstractThe development of responsive slippery surfaces is important because of the high demand for such materials in the fields of liquid manipulation on biochips, microfluidics, microreactions, and liquid‐harvesting devices. Although great progress has been achieved, the effect of substrate wettability on slippery surfaces stability is overlooked by scientists. In addition, current responsive slippery surfaces generally function utilizing single external stimuli just for imprecisely controlling liquid motion, while advanced intelligences are always expected to be integrated into one smart interface material for widespread multifunctional applications. Therefore, designing slippery surfaces that collaboratively respond to complex external stimuli and possess sophisticated composite function for expanding applications from controlling droplets motion to patterned writing is urgently needed but remains a challenge. Here, a photoelectric cooperative‐responsive slippery surface based on ZnO nanoporous composites is demonstrated. First, the effect of composite surface wettability on slippery surface stability is systematically researched and the optimum wettability region for fabricating stable slippery surfaces is determined. Furthermore, controllable droplet motion and patterned writing are realized on the same slippery surfaces under photoelectric cooperative stimuli, and the related response mechanism is also deeply studied. This kind of material has potential applications in biochips, microfluidics, in situ patterning, and water‐harvesting systems.
Double Ring‐Expanding Carbonylation Using an In Situ Generated Aluminum Phthalocyanine Cobalt Carbonyl Complex
Authors: Jiang Jianwei , Rajendiran Senkuttuvan , Yoon Sungho 
Published: November 2018

AbstractThe ring‐expanding carbonylation of epoxides provides an efficient one‐step procedure for synthesizing β‐lactones and succinic anhydride derivatives. Although porphyrin‐based catalysts generally show excellent catalytic activities in the ring‐expanding carbonylation of epoxides, the application of porphyrin catalysts is limited owing to the low yield and high cost of preparing porphyrins. This study aims to propose a new and highly efficient catalytic system for the carbonylation of propylene oxide (PO) using an in situ generated active catalyst from cost‐effective and readily available aluminum phthalocyanine chloride (AlPcCl) and dicobalt octacarbonyl (Co2(CO)8). The catalyst showed not only excellent catalytic activities of single carbonylation but also double carbonylation resulting in anhydride by judicious choice of reaction parameters, such as reaction temperature and the ratio of PO to catalyst. This is the first report on the use of an in situ generated catalyst for the one‐pot double carbonylation of epoxide to anhydride.
Chiral Sulfide Catalysis for Desymmetrizing Enantioselective Chlorination
Authors: Cao Qingxiang , Luo Jie , Zhao Xiaodan 
Published: November 2018

AbstractAn unprecendented chiral sulfide catalyzed desymmetrizing enantioselective chlorination is disclosed. Various aryl‐tethered diolefins and diaryl‐tethered olefins afforded teralins and tricyclic hexahydrophenalene derivatives, respectively, bearing multiple stereogenic centers in high yields with excellent enantio‐ and diastereoselectivities. In contrast, the tertiary amine catalyst (DHQD)2PHAL led to a diastereomeric product. The products could be transformed into a variety of compounds, such as spiro‐N‐heterocycles.
Synthesis of Gossypium hirsutum‐derived silver nanoparticles and their antibacterial efficacy against plant pathogens
Authors: Vanti Gulamnabi L. , Nargund Vijendra B. , N Basavesha K. , Vanarchi Rajinikanth , Kurjogi Mahantesh , Mulla Sikandar I. , Tubaki Suresh , Patil Rajashekar R. 
Published: November 2018

Malvaceae and Brassicaceae family crops are economically important; however, their production has been markedly decreased in recent years due to various plant pests. Hence, the search for novel classes of efficient biological approaches continues due to unavailability of precise pesticides. The present study was designed to synthesize, characterize and evaluate the efficacy of silver nanoparticles (AgNPs) obtained using stem extract of Gossypium hirsutum (cotton plant) against plant pathogens Xanthomonas axonopodis pv. malvacearum and Xanthomonas campestris pv. campestris. Biosynthesized AgNPs were characterized using UV–visible spectrophotometry, Dynamic Light Scattering, Scanning Electron Microscopy combined with energy‐dispersive X‐ray analysis and Fourier transform infrared spectroscopy. The synthesized AgNPs were spherical in shape with size ranging from 20 to 100 nm. The characterized AgNPs were investigated for their efficacy against bacterial plant pathogens using the paper disc method. In vitro studies with two concentrations of AgNPs (50 and 100 μg mL−1) showed zone of inhibition 11.0 ± 1.0 and 12.3 ± 0.5 mm for X. axonopodis pv. malvacearum and 9.7 ± 0.6 and 15.33 ± 1.0 mm for X. campestris pv. campestris. Furthermore, the AgNPs exhibited strong antioxidant activity, and a phytotoxicity study on Vigna unguiculata (cowpea plant) showed no toxicity. Overall, the findings suggest that G. hirsutum stem extract could be efficiently used in the synthesis of AgNPs and showed antimicrobial activity against plant pathogens. Hence, the synthesized nanoparticles could be used to combat plant pathogens in the agriculture sector.
Influence of imide functionalized organo‐modified Mg‐Al layered double hydroxide on the thermal and mechanical properties of new aliphatic‐aromatic poly (amide‐imide)
Authors: Hajibeygi Mohsen , Shafiei‐Navid Saeid , Shabanian Meisam 
Published: November 2018

A new dicarboxylic acid modified Mg‐Al LDH (DLDH) containing imide groups was prepared and its effects on the thermal and mechanical properties of the new synthesized aliphatic‐aromatic poly (amide‐imide) (PAI) were investigated via preparation of PAI/nanocomposite films by solution casting method. The results of X‐ray diffraction (XRD), field emission‐scanning electron microscopy (FE‐SEM) and transmission electron microscopy (TEM) showed a uniform dispersion for LDH layers into the PAI matrix. For comparison, the effects of polyacrylic acid‐co‐poly‐2‐acrylamido‐ 2‐methylpropanesulfonic acid (PAMPS‐co‐PAA) modified Mg‐Al LDH (ALDH) on the PAI properties were also studied. The thermogravimetric analysis (TGA) results exhibited that the temperature at 5 mass% loss (T5) increased from 277 °C to 310 °C for nanocomposite containing 2 mass% of DLDH, while T5 for nanocomposite containing 2 mass% of ALDH increased to 320 °C, along with the more enhancement of char residue compared to the neat PAI. According to the tensile test results, with 5 mass% DLDH loading in the PAI matrix, the tensile strength increased from 51.6 to 70.8 MPa along with an increase in Young's modulus. Also the Young's modulus of PAI nanocomposite containing 5 mass% ALDH reduced from 1.95 to 0.81 GPa.
Water channel activity of putative aquaporin‐6 present in Aedes aegypti
Authors: Sreedharan Sandhya , Sankaranarayanan Kavitha 
Published: November 2018

AbstractAquaporins (AQPs) are integral membrane channels that facilitate the bidirectional transport of water and sometimes other small solutes across biological membranes. AQPs are important in mediating environmental adaptations in mosquitoes and are considered as a novel target for the development of effective insecticides against mosquitoes. Here, we expressed Aedes aegypti AQP6 (
AaAQP6) in human embryonic kidney (HEK) 293 cells and analyzed the water permeability by a conventional swelling assay, that is, a real‐time change in cell size corresponding to the cell swelling induced by hyposmotic solution. The swelling assay revealed that
AaAQP6 is a mercury‐sensitive water channel. Gene expression studies showed that
AaAQP6 is highly expressed in the pupae than other developmental stages. Heterologous expression of
AaAQP6 in HEK cell was mainly observed intracellularly suggesting
AaAQP6 possibly could be a subcellular water channel and may play an osmoregulatory function in the pupae of
A. aegypti.
Magnetic field modelling and analysis of uncertainty in archaeological geophysics
Authors: Schettino Antonio , Ghezzi Annalisa , Pierantoni Pietro Paolo 
Published: November 2018

AbstractOne of the major problems in the forward modelling of magnetic anomalies is the assessment of a minimum level of acceptable accuracy in the fit between observed and theoretical anomalies. We present a new approach to the analysis and interpretation of archaeological magnetic anomalies, based on classical algorithms of forward modelling and a new technique of error assessment. This approach allows us to determine geometry, physical properties, and location of buried archaeological features, as well as the occurrence of fires or other historical events that may have affected the observed magnetic signal. Our method starts from the acquisition of total field data, usually in a regular grid arrangement, and proceeds through their reduction to archaeological magnetic anomalies. This reduction is performed subtracting from the observed total field data a polynomial representation of the regional field, on the basis of a rigorous criterion that tries to separate archaeological anomalies from geological (crustal) contributions. At the next step, a map of the maximum allowed misfit is built, which depends from the estimated uncertainty at each point of the magnetic anomaly field. This map specifies the maximum allowed deviation of theoretical anomalies from the observed values. The last step is the analysis of these anomalies through a new forward modelling tool, with the objective to reconstruct the three‐dimensional arrangement of buried features and possibly obtain some information about the history.
A new derivatization method for the determination of valproic acid in serum using tetramethylammonium hydroxide as a catalyst
Authors: Mao Guifu , Zhao Kun , Sun Shusen , Lu Yanxia , Li Xingang 
Published: November 2018

AbstractValproic acid (VPA) pharmacokinetics is highly variable and monitoring of blood levels is necessary to determine its appropriate dosage. This study aimed to establish and validate a novel derivatization method for the determination of VPA. The method was based on the catalytic effect of tetramethylammonium hydroxide using 2,4′‐dibromoacetophenone as a derivatization reagent. After derivatization, samples were injected into the HPLC system for analysis. The method showed a good linearity in the range of 1.0–200.7 μg mL−1, and the limit of quantification was 1 μg mL−1. All values of the accuracy and relative standard deviations were acceptable for the analyses of biological samples. The recoveries were in the range from 91.6 to 97.4% for VPA with RSD <3.9%. A novel and high conversion‐rate derivatization method has been developed and validated for the determination of VPA in human serum. It can be applied to the analysis of VPA in clinic serum samples.
Influence of Linker Length on Ligase‐Catalyzed Oligonucleotide Polymerization
Authors: Guo Chun , Mahdavi‐Amiri Yasaman , Hili Ryan 
Published: November 2018

AbstractLigase‐catalyzed oligonucleotide polymerization (LOOPER) that enables the sequence‐defined generation of DNA with up to 16 different modifications has recently been developed. This approach was used to develop new classes of diversely modified DNA aptamers for molecular recognition through in vitro evolution. The modifications in LOOPER are appended by use of a long hexane‐1,6‐diamine linker, which could negatively impact binding thermodynamics. Here we explore the incorporation of modifications with the aid of shorter linkers and the use of commercially available phosphoramidites and assess their efficiency and fidelity of incorporation. We observed that shorter linkers are less tolerated during LOOPER, with very short linkers providing high levels of error and sequence bias. An ethane‐1,2‐diamine linker was found to be optimal in terms of yield, efficiency, and bias; however, codon adjustment was necessary. This shorter‐linker anticodon set for LOOPER should prove valuable in exploring the impact of diverse chemical modifications on the molecular function of DNA.