bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic diversity and phylogenetic analysis of native mountain ponies of Britain and Ireland reveals a novel rare population
Authors: Winton Clare L. , Hegarty Matthew J. , McMahon Robert , Slavov Gancho T. , McEwan Neil R. , Davies‐Morel Mina C.G. , Morgan Charly M. , Powell Wayne , Nash Deborah M. 
Published: March 2013

AbstractThe conservation of unique populations of animals is critical in order to preserve valuable genetic diversity and, where populations are free‐living, maintain their irreplaceable influence upon habitat ecology. An accurate assessment of genetic diversity and structure within and between populations is crucial in order to design and implement conservation strategies in natural and domesticated species. Moreover, where it is possible to identify relic populations that are related to a structured breed an ideal opportunity presents itself to model processes that reveal historical factors that have shaped genetic diversity. The origins of native UK mountain and moorland ponies are uncertain, but they may have directly descended from prehistoric populations and potentially harbour specific adaptations to the uplands of Britain and Ireland. To date, there have been no studies of population structure and genetic diversity present within a free‐living group of ponies in the Carneddau mountain range of North Wales. Herein, we describe the use of microsatellites and SNPs together with analysis of the mitochondrial control region to quantify the extent and magnitude of genetic diversity present in the feral Carneddau pony and relate this to several recognised British and Irish pony breeds. Our results establish that the feral Carneddau ponies represent a unique and distinctive population that merits recognition as a defined population and conservation priority. We discuss the implications for conservation of this population as a unique pool of genetic diversity adapted to the British uplands and potentially of particular value in maintaining the biodiversity of these habitats.
Preparation of Mesoporous Titania Thin Films with Well‐Crystallized Frameworks by Using Thermally Stable Triblock Copolymers
Authors: Zakaria Mohamed B. , Suzuki Norihiro , Torad Nagy L. , Matsuura Mikiya , Maekawa Kazuhiko , Tanabe Hirofumi , Yamauchi Yusuke 
Published: March 2013

AbstractMesoporous titania (TiO2) thin films are prepared by a spin‐coating method using new laboratory‐made polystyrene‐block‐polybutadiene‐block‐polystyrene‐based triblock copolymers in which the polystyrene block is functionalized with hydrophilic sulfonic groups (abbreviated as sulfonated HmSEBmS). The polymer used in this study is more thermally stable than commercial Pluronic‐type block copolymers (e.g. P123 and F127). As‐prepared TiO2 thin films are calcined under various temperatures. The calcined films are systematically characterized by low‐angle and wide‐angle XRD, scanning electron microscopy (SEM), and nitrogen gas adsorption–desorption isotherms. As calcination temperatures increase, crystal growth proceeds in the pore walls and the phase transformation from anatase to rutile occurs. Even after calcination at 550 and 600 °C, the thin films nicely preserve high surface areas. On the other hand, the surface areas of mesoporous TiO2 prepared from P123 are markedly decreased after calcination at 550 °C.
Thermally Reversible, Flexible, Transparent, and Luminescent Ionic Organosilica Gels
Authors: Ru Qiaorong , Wang Yige , Zhang Wenjun , Yu Xiaoyan , Li Huanrong 
Published: March 2013

AbstractHerein, we report a facile method to prepare thermally reversible, flexible, transparent, and luminescent ionic organosilica gels with tunable emission colors. The reaction of an amino‐functionalized ionic liquid ([NH2‐Bim]Br) with 3‐(triethoxysilyl)propyl isocyanate results in an ionic‐liquid‐modified alkoxysilane, the hydrolysis and condensation of which lead to thermally reversible, flexible, and luminescent ionic gels in the presence of lanthanide species. The luminescence color can be fine‐tuned by changing the Ln3+ ions (Eu3+, Tb3+, or a mixture of Eu3+ and Tb3+) and by changing the excitation wavelength. The absolute quantum yields of the flexible luminescent gels with europium(III) and terbium(III) complexes are determined to be 15 and 21 %, respectively, by using an integrating sphere. The thermal reversibility of the organosilicas makes them attractive for the development of flexible optical devices and flexible luminescent devices such as organic light‐emitting diodes (OLEDs).
Glycosynthase with Broad Substrate Specificity – an Efficient Biocatalyst for the Construction of Oligosaccharide Library
Authors: Wei Jinhua , Lv Xun , Lü Yang , Yang Gangzhu , Fu Lifeng , Yang Liu , Wang Jianjun , Gao Jianhui , Cheng Shuihong , Duan Qian , Jin Cheng , Li Xuebing 
Published: March 2013

AbstractA versatile glycosynthase (TnG‐E338A) with strikingly broad substrate scope has been developed from Thermus nonproteolyticus β‐glycosidase (TnG) by using site‐directed mutagenesis. The practical utility of this biocatalyst has been demonstrated by the facile generation of a small library containing various oligosaccharides and a steroidal glycoside (total 25 compounds) in up to 100 % isolated yield. Moreover, an array of eight gluco‐oligosaccharides has been readily synthesized by the enzyme in a one‐pot, parallel reaction, which highlights its potential in the combinatorial construction of a carbohydrate library that will assist glycomic and glycotherapeutic research. Significantly, the enzyme provides a means by which glycosynthase technology may be extended to combinatorial chemistry.
Synthesis of Nopinone from β‐Pinene – A Journey Revisiting Methods for Oxidative Cleavage of C=C Bonds in Terpenoid Chemistry
Authors: Stolle Achim 
Published: March 2013

AbstractThe synthesis of nopinone from β‐pinene is an interesting model reaction for the investigation of methods for the oxidative cleavage of C=C bonds. Nopinone is used as chiral component for the total synthesis of different ligands or natural compounds such as di‐ or sesquiterpenes, as well as for the production of pharmaceutically active components. The cleavage of the C(2)=C(10) bond in β‐pinene by suitable oxidants leads to the replacement of the exo‐methylene functionality by a carbonyl group, which is more suitable for subsequent synthetic steps and the construction of complex condensed ring systems. Oxidants such as ozone, potassium permanganate, or sodium periodate have been applied successfully for this reaction. Ozonolysis of the double bond follows the classical Criegee mechanism, after which the secondary intermediate is isolated and reductive workup yields the carbonyl products. Dihydroxylation of the double bond can be initiated by permanganate or periodate. Further oxidation leads to the same products known from ozonolysis. Periodate oxidations in particular can be supported by catalysts such as RuCl3 or OsO4, because the oxidant is generally too weak to dihydroxylate the double bond. OsO4‐catalyzed reactions, for example, can take advantage of a co‐oxidant such as trimethylammonium N‐oxide for the dihydroxylation step. Other oxidants such as hydrogen peroxide or dioxygen have also been tested but with minor success with respect to conversion or selectivity.
Synthesis of 1,2‐Diaryl‐1H‐indol‐4‐ols and 1,2‐Diaryl‐7‐ethoxy‐1,5,6,7‐tetrahydroindol‐4‐ones from Arylglyoxals and Enamines through Domino Reactions
Authors: Maity Subhendu , Pathak Sudipta , Pramanik Animesh 
Published: March 2013

AbstractA series of 1,2‐diaryl‐ and 1‐alkyl‐2‐aryl‐1H‐indol‐4‐ols and 1,2‐diaryl‐7‐ethoxy‐1,5,6,7‐tetrahydroindol‐4‐ones have been prepared by the domino reactions of arylglyoxals and enamines at reflux in non‐nucleophilic and nucleophilic solvents such as acetonitrile and ethanol, respectively. The transformation occurs by annulation followed by aromatization without the use of any metal or catalyst.
Synthesis of Photoreactive 2‐Phenethylamine Derivatives – Synthesis of Adenosine Derivatives Enabling Functional Analysis of Adenosine Receptors by Photoaffinity Labeling
Authors: Murai Yuta , Masuda Katsuyoshi , Ogasawara Yui , Wang Lei , Hashidoko Yasuyuki , Hatanaka Yasumaru , Iwata So , Kobayashi Takuya , Hashimoto Makoto 
Published: March 2013

Abstract2‐Phenylethylamine is well known as a substructure of many biologically active compounds, and the synthesis of its photoreactive derivatives to allow the analysis of biological functions is reported. This allowed us to synthesise ligands for adenosine receptors, which have many functional roles in biology and have been extensively studied for their many roles in maintaining homeostasis. Adenosine is one of the most common biochemical compounds, but photoaffinity labeling has not yet been used to study adenosine receptors. Synthetic methods for producing photoreactive adenosine derivatives that can be used with adenosine receptors were established for the photophores phenyl azide and benzophenone. The effect of the introduction of the photoreactive components was determined using an adenosine receptor assay.
Synthesis of (+)‐Centrolobine and Its Analogues by Using Acyl Anion Chemistry
Authors: Sudarshan Kasireddy , Aidhen Indrapal Singh 
Published: March 2013

AbstractA new route based on the use of acyl anion chemistry was developed for the synthesis of (+)‐centrolobine and its analogues. Acid‐catalyzed benzylic cation initiated cyclization was the key step in the stereoselective formation of the cis‐2,6‐disubstituted tetrahydropyran ring. The developed methodology was applied to the synthesis of (+)‐centrolobine analogues containing electron‐donating substituents in the aryl rings.
Electrochemical Sensing of Dissolved Hydrogen in Aqueous Solutions as a Tool to Monitor Magnesium Alloy Corrosion
Authors: Kuhlmann Julia , Witte Frank , Heineman William R. 
Published: March 2013

AbstractMagnesium and its alloys have been the focus of the development of biodegradable metallic implant materials for years. Since water is reduced to form hydrogen gas during their corrosion, the amount and rate of hydrogen evolution, and therefore the dissolved hydrogen, could be used as an indicator to monitor and compare the corrosion. Here we report on a commercially available Clark‐Type amperometric microsensor and a simple potentiometric sensor for hydrogen to monitor the corrosion of a magnesium alloy in aqueous solutions. The sensors were compared using rare‐earth containing Mg alloy discs (Mg with 4 % Y, 2 % Nd, 0.5 % Ga, 0.5 % Dy) immersed in phosphate buffered saline (pH 7.4) and 3.5 % NaCl.
A Sensitive Microchip‐Based Immunosensor for Electrochemical Detection of Low‐Level Biomarker S100B
Authors: Liu Yun , Wang Huixiang , Chen Jiayao , Liu Chengcheng , Li Wenxian , Kong Jilie , Yang Pengyuan , Liu Baohong 
Published: March 2013

AbstractA sensitive microchip‐based electrochemical immunosensor has been developed for quantification of low level S100B, which is an important biomarker of neurological diseases. Poly(ethyleneimine) (PEI), containing NH2 groups, was firstly modified on the surface of the poly(methyl methacrylate) (PMMA) microchannel to capture monoclonal anti‐S100B. Afterward, S100B and second polyclonal anti‐S100 were sequentially coupled by antigen‐antibody specific interaction, and the alkaline phosphatase conjugates (ALP‐conjugates) were bound to the second antibodies in a PMMA microchannnel. Using differential pulse voltammetry (DPV), the immunosensor achieved the detection limit of 0.1 pg mL−1 with the linear concentration range of 0.1 pg  mL−1–100 pg mL−1. The results indicate that the proposed strategy not only has high specificity and sensitivity, but also resists nonspecific protein adsorption. The disposable microchip immunosensor shows good promise for clinical screening of important biomarkers and convenient point‐of‐care diagnostics.
Electrochemical Pseudo‐Titration of Water‐Soluble Antioxidants
Authors: Tacchini Philippe , Lesch Andreas , Neequaye Alice , Lagger Grégoire , Liu Jifeng , Cortés‐Salazar Fernando , Girault Hubert H. 
Published: March 2013

AbstractAn amperometric test for the antioxidant power (AOP) of biological and food samples is presented. The gist of the method is to measure by linear sweep voltammetry the anodic current produced during the oxidation of the labile species present in the sample and then rationalizing this signal with a mathematical treatment that allows the pseudo‐titration of antioxidants (AOs) around a given threshold potential. As a result, the AOP of the sample is calculated. This method allows the discrimination of the most biologically relevant AOs that react rapidly and at low oxidation potentials, from less reactive AOs that are oxidised slowly and at much higher oxidation potentials. This methodology was applied for measuring the AOP of blood, saliva, and natural drinks like orange juice.
Adsorption and Electrooxidation of Nucleic Acids at Glassy Carbon Electrodes Modified with Multiwalled Carbon Nanotubes Dispersed In Polylysine
Authors: Jalit Yamile , Moreno Mónica , Gutierrez Fabiana A. , Sanchez Arribas Alberto , Chicharro Manuel , Bermejo Esperanza , Zapardiel Antonio , Parrado Concepción , Rivas Gustavo A. , Rodríguez Marcela C. 
Published: March 2013

AbstractWe report the advantages of the adsorption and electrooxidation of oligonucleotides and calf‐thymus double stranded DNA (dsDNA) at glassy carbon electrodes (GCE) modified with a dispersion of multiwalled carbon nanotubes (MWCNT) in poly‐L‐lysine (Plys) (GCE/MWCNT‐Plys). Important enhancement in the guanine oxidation signal was obtained by adsorptive stripping voltammetry (AdSV) due to a most favorable interaction between the negatively charged DNAs and the positively charged Plys that support the MWCNT. The layer of oligo(dG)11 immobilized at GCE/MWCNT‐Plys was successfully used for the selective detection of the hybridization event using oligo(dG)11/oligo(dC)11 as model.
Electrochemical Behaviour of Isoflavones Genistein and Biochanin A at a Glassy Carbon Electrode
Authors: Popa Oana M. , Diculescu Victor C. 
Published: March 2013

AbstractThe electrochemical behaviour of genistein and biochanin A was studied at a glassy carbon electrode by cyclic, differential pulse and square wave voltammetry. Genistein undergoes three irreversible, pH dependent oxidation reactions with the transfer of one electron and one proton from each hydroxyl group. The formation of two electroactive products that undergo reversible redox reactions was observed. Biochanin A undergoes two irreversible, pH dependent reactions due to the oxidation of the two hydroxyl groups. The electrochemical behaviour of the chemical analogue daidzein was also investigated. The electroactive centres of genistein and biochanin A were identified and their oxidation mechanisms discussed.
Label‐Free Amperometric Magnetoimmunosensors for Direct Determination of Lactoperoxidase in Milk
Authors: Torrente‐Rodríguez Rebeca M. , Campuzano Susana , Gamella María , Conzuelo Felipe , Reviejo A. Julio , Pingarrón José M. 
Published: March 2013

AbstractNovel label free electrochemical magnetoimmunosensors for the determination of lactoperoxidase (LPO) were developed based on the use of streptavidin‐magnetic beads (Strep‐MBs) and graphite‐Teflon composite or screen‐printed carbon electrodes (SPCEs) as electrochemical transducers. Biotinylated antiLPO antibodies were immobilized onto the Strep‐MBs and a direct‐type immunoassay by detecting the enzymatic activity of the captured target enzyme using amperometric detection at −0.20 V and the H2O2/hydroquinone (HQ) system was employed. The SPCEs‐based magnetoimmunosensors allowed a detection limit (LOD) of 0.12 μg mL−1 and a good selectivity against nontarget proteins. Moreover, their analytical usefulness was successfully demonstrated by analyzing different types of milk samples.
Simple and Sensitive Electrochemical DNA Detection of Primer Generation‐Rolling Circle Amplification
Authors: Lee Derek Chun , Yip Shea Ping , Lee Thomas M. H. 
Published: March 2013

AbstractA new electrochemical sequence‐specific DNA detection platform based on primer generation‐rolling circle amplification (PG‐RCA), methylene blue (MB) redox indicator, and indium tin oxide (ITO) electrode is reported. In the presence of a specific target sequence, PG‐RCA, an isothermal DNA amplification technique, produced large amounts of amplicons in an exponential manner. In addition to the standard components, the reaction mixture contained MB, which bound with the PG‐RCA amplicons. End‐point electrochemical measurement by differential pulse voltammetry (DPV) was performed using ITO electrode. The amplicon‐bound MB resulted in a lower DPV signal than free MB due to a smaller diffusion coefficient as well as electrostatic repulsion between the negatively charged amplicon‐bound MB and ITO electrode. With simple assay design (recognition probe) and instrumentation (operating temperature at 37 °C and ITO electrode without the need for probe immobilization), this detection platform is well suited for point‐of‐care and on‐site testing. Real‐time measurement was also achieved by pretreating the ITO electrode with bovine serum albumin.
How systematic is organized tropical convection within the MJO?
Authors: Dias J. , Leroux S. , Tulich S. N. , Kiladis G. N. 
Published: March 2013

AbstractRecent theories of the dynamics of the Madden‐Julian Oscillation (MJO) have been building on its multiscale structure. While it is observed that much of the convection within the MJO envelope is related to higher frequency equatorial waves, it is not known to what extent this organization is systematic from one MJO event to another. For instance, it is of interest to know whether MJO favors waves of particular types and propagation direction, and how this variability changes seasonally. This work presents a wavenumber‐frequency spectral analysis of the MJO convective envelope, which indicates that there is no strong preferred scale of high frequency organization that is ubiquitous to the MJO. This null finding supports the use of convective parametrizations in modeling the MJO since, while moist convection is likely critical to its initiation and maintenance, the particular details of that organization may not be critical for its prediction and simulation.
Triple check: Observations verify structural realism of an ocean ecosystem model
Authors: Santora Jarrod A. , Sydeman William J. , Messié Monique , Chai Fei , Chao Yi , Thompson Sarah Ann , Wells Brian K. , Chavez Francisco P. 
Published: March 2013

AbstractImprovements in fisheries and ecosystem management could be made if the prediction of key zooplankton, such as krill, were possible using ocean ecosystem models. To examine structural realism, hence the validity of a coupled physical‐biogeochemical model, we compared measured spatiotemporal dynamics of krill and seabird abundance off California to hindcasted mesozooplankton derived from an independently designed model. Observed krill and modeled mesozooplankton (Z2) displayed latitudinal coherence but distinct longitudinal offsets, possibly related to unrealistic bathymetry in the model. Temporally, Z2, Thysanoessa spinifera (a neritic krill species) and seabird density and reproductive performance were well correlated, indicating that quantitative prediction regarding marine predators in upwelling ecosystems is within reach. Despite its basin‐scale framework, the ROMS‐CoSiNE model captures zooplankton and top predator dynamics regionally in the central California region, suggesting its utility for management of marine ecosystems and highlighting rapid advances that can be made through collaboration between empirical scientists and ecosystem modelers.
The influence of fracture anisotropy on CO2 flow
Authors: Bond Clare E. , Wightman Ruth , Ringrose Philip S. 
Published: March 2013

AbstractGreenhouse gas mitigation through geological storage of carbon dioxide is dependent on rock formations storing CO2 effectively. Secure containment for periods of 100 × 105 years nee7ds to be verifiable. The effectiveness of geological storage is reliant on the chemical and physical properties of the geological storage complex and its ability to inhibit migration of CO2. Petroleum reservoir data and field evidence show that fracture networks often act as pathways for fluid movement, potentially allowing fluids to migrate to the surface within the time scale of interest. We demonstrate the importance of predicting the effects of fracture networks on flow, using a case study from the In Salah CO2 storage site, and show how fracture permeability is closely controlled by the stress regime determining the conductive fracture network. Our results demonstrate that fracture network prediction combined with present‐day stress analysis can be used to successfully predict CO2 movement in the subsurface.
Effects of the GABA‐uptake blocker NNC‐711 on spontaneous sharp wave–ripple complexes in mouse hippocampal slices
Authors: Viereckel Thomas , Kostic Milos , Bähner Florian , Draguhn Andreas , Both Martin 
Published: March 2013

AbstractThe precise temporal and spatial activity patterns of neurons in cortical networks are organized by different state‐dependent types of network oscillations. GABAergic inhibition plays a key role in the underlying mechanisms of such oscillations and it has been suggested that the duration of widely distributed phasic inhibitory postsynaptic potentials (IPSPs) determines the frequency of the resulting network oscillation. Here, we test this hypothesis in an in vitro model of sharp wave–ripple (SPW‐R) complexes, a particularly fast pattern of network oscillations at ∼200 Hz which is involved in memory consolidation. We recorded SPW‐R in mouse hippocampal slices in the absence and presence of NCC‐711, an inhibitor of GABA uptake. The resulting prolongation of IPSP resulted in reduced occurrence of SPW‐R, whereas the superimposed fast oscillations as well as the precision of rhythmic cell synchronization remained stable. Application of Diazepam which is a positive modulator of the GABAA receptor led to consistent results. We conclude that phasic inhibition is a major regulator of network excitability in CA3 (where SPW‐Rs are generated), but does not set the frequency of hippocampal ripples. © 2013 Wiley Periodicals, Inc.
Differential roles of the dorsal and ventral hippocampus in predator odor contextual fear conditioning
Authors: Wang Melissa E. , Fraize Nicolas P. , Yin Linda , Yuan Robin K. , Petsagourakis Despina , Wann Ellen G. , Muzzio Isabel A. 
Published: March 2013

AbstractThe study of fear memory is important for understanding various anxiety disorders in which patients experience persistent recollections of traumatic events. These memories often involve associations of contextual cues with aversive events; consequently, Pavlovian classical conditioning is commonly used to study contextual fear learning. The use of predator odor as a fearful stimulus in contextual fear conditioning has become increasingly important as an animal model of anxiety disorders. Innate fear responses to predator odors are well characterized and reliable; however, attempts to use these odors as unconditioned stimuli in fear conditioning paradigms have proven inconsistent. Here we characterize a contextual fear conditioning paradigm using coyote urine as the unconditioned stimulus. We found that contextual conditioning induced by exposure to coyote urine produces long‐term freezing, a stereotypic response to fear observed in mice. This paradigm is context‐specific and parallels shock‐induced contextual conditioning in that it is responsive to extinction training and manipulations of predator odor intensity. Region‐specific lesions of the dorsal and ventral hippocampus indicate that both areas are independently required for the long‐term expression of learned fear. These results in conjunction with c‐fos immunostaining data suggest that while both the dorsal and ventral hippocampus are required for forming a contextual representation, the ventral region also modulates defensive behaviors associated with predators. This study provides information about the individual contributions of the dorsal and ventral hippocampus to ethologically relevant fear learning. © 2013 Wiley Periodicals, Inc.