bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Threose Nucleic Acid (TNA) Triphosphates and Oligonucleotides by Polymerase‐Mediated Primer Extension
Authors: Zhang Su , Yu Hanyang , Chaput John C. 
Published: March 2013

AbstractThis unit describes the chemical synthesis of α‐L‐threofuranosyl nucleic acid (TNA) triphosphates for thymidine (T), guanosine (G), cytidine (C), and the diaminopurine (D) analog of adenosine and their incorporation into TNA oligonucleotides by enzyme‐mediated polymerization of a DNA primer‐template complex. Starting from suitably protected threofuranosyl nucleosides, TNA triphosphates are synthesized in a single‐pot reaction and purified by ion‐exchange and HPLC chromatography. Purified TNA triphosphates are diluted into stock solutions and used as substrates for the synthesis of TNA oligonucleotides. Oligonucleotide synthesis is accomplished using Therminator DNA polymerase, a commercial variant of the 9oN DNA polymerase bearing the A485L mutation. Curr. Protoc. Nucleic Acid Chem. 52:4.54.1‐4.54.17. © 2013 by John Wiley & Sons, Inc.
Electron beam and UV cationic polymerization of glycidyl ethers PART II: Reaction of diglycidyl ether of bisphenol A
Authors: Mascioni Matteo , Ghosh Narendra N. , Sands James M. , Palmese Giuseppe R. 
Published: March 2013

AbstractElectron‐beam (e‐beam) and ultraviolet (UV)‐induced cationic polymerization of diglycidyl ether of bisphenol A (DGEBA) using the photo‐initiator diaryliodonium hexafluoroantimonate was investigated using in situ NIR spectroscopy. The effect of processing parameters, such as temperature, radiation intensity, and photo‐initiator concentration, on kinetics of the reaction were determined quantitatively. In contrast to the behavior of monofunctional epoxy systems reported previously, the difunctional epoxy forms a high Tg crosslinked network, so a kinetic model that takes into account diffusion limitations associated with vitrification was developed. The combined benefits of the real‐time in situ NIR spectroscopy study and the well‐defined diffusion model resulted in very accurate predictions for cure of epoxy networks by e‐beam‐induced polymerization. The results support the view that e‐beam processing of epoxies is constrained by vitrification in the same way that UV and thermally cured epoxies are. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Luminescent Noble Metal Nanoclusters as an Emerging Optical Probe for Sensor Development
Authors: Yuan Xun , Luo Zhentao , Yu Yong , Yao Qiaofeng , Xie Jianping 
Published: March 2013

AbstractIn the past few years, highly luminescent noble metal nanoclusters (e.g., Au and Ag NCs or Au/Ag NCs in short) have emerged as a class of promising optical probes for the construction of high‐performance optical sensors because of their ultrasmall size (<2 nm), strong luminescence, good photostability, excellent biocompatibility, and unique metal‐core@ligand‐shell structure. In this Focus Review, we briefly summarize the common syntheses for water‐soluble highly‐luminescent thiolate‐ and protein‐protected Au/Ag NCs and their interesting luminescence properties, highlight recent progress in their use as optical sensors with an emphasis on the mechanisms underlying their selectivity, and finally discuss approaches to improving their sensitivity. The scope of the works surveyed is confined to highly luminescent thiolate‐ and protein‐protected Au/Ag NCs.
Colorimetric and Fluorescent Chemosensors for the Detection of 2,4,6‐Trinitrophenol and Investigation of their Co‐Crystal Structures
Authors: Dong Ming , Wang Ya‐Wen , Zhang Ai‐Jiang , Peng Yu 
Published: March 2013

AbstractA full account of our studies of 2,4,6‐trinitrophenol (TNP) sensing is provided. A series of chemosensors 2, 3, 4, 5 with a variety of aromatic chromophores for specific recognition of TNP has been designed and then realized through the fluorescence “on/off” mechanism. These chemosensors demonstrated highly selective, sensitive, and fluorescent quenching of TNP with remarkable visual changes through the intramolecular charge‐transfer (ICT) process. Their host–guest interactions were investigated by 1H NMR spectroscopic titrations and their corresponding co‐crystal structures, which showed that the 1:1 host–guest complexes were formed by multiple hydrogen‐bond interactions in solution or in the solid state. The origins of the significant affinity demonstrated during the fluorescence recognition process were further disclosed through DFT calculations of corresponding compounds.
Biomass and bioenergy in the wider land‐use context of the European Union
Authors: Allen Benjamin R , Keegan Dearbhla , Elbersen Berien 
Published: March 2013

AbstractDemands from land are increasing within the EU. Targets set out under the Renewable Energy Directive (RED) are driving the production of energetic biomass for use within the energy sector and, at the same time, changing populations, diets, and societal preferences are leading to increased demands for other types of biomass including food, feed, and fiber. As an inherently multifunctional natural resource, land is already meeting many of these demands as well as providing a wider range of services to society including clean and reliable water, carbon sequestration, and cultural services. However, as demands from land increase, its continued ability to support a range of different sectors sustainably is called into question.This review considers the EU demand for bioenergy and the biomass used to produce it, to 2020, within the wider land‐use context. It reflects on the different demands facing the EU and global land resources beyond those emanating from the energy sector, their drivers, and the implications for land resources as a central element in the development of sustainable biomass supply chains in the EU. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd
The Minimum Activation Peptide from ilvH Can Activate the Catalytic Subunit of AHAS from Different Species
Authors: Zhao Yuefang , Niu Congwei , Wen Xin , Xi Zhen 
Published: March 2013

AbstractAcetohydroxyacid synthases (AHASs), which catalyze the first step in the biosynthesis of branched‐chain amino acids, are composed of a catalytic subunit (CSU) and a regulatory subunit (RSU). The CSU harbors the catalytic site, and the RSU is responsible for the activation and feedback regulation of the CSU. Previous results from Chipman and co‐workers and our lab have shown that heterologous activation can be achieved among isozymes of Escherichia coli AHAS. It would be interesting to find the minimum peptide of ilvH (the RSU of E. coli AHAS III) that could activate other E. coli CSUs, or even those of ## species. In this paper, C‐terminal, N‐terminal, and C‐ and N‐terminal truncation mutants of ilvH were constructed. The minimum peptide to activate ilvI (the CSU of E. coli AHAS III) was found to be ΔN14–ΔC89. Moreover, this peptide could not only activate its homologous ilvI and heterologous ilvB (CSU of E. coli AHAS I), but also heterologously activate the CSUs of AHAS from Saccharomyces cerevisiae, Arabidopsis thaliana, and Nicotiana plumbaginifolia. However, this peptide totally lost its ability for feedback regulation by valine, thus suggesting different elements for enzymatic activation and feedback regulation. Additionally, the apparent dissociation constant (Kd) of ΔN14–ΔC89 when binding CSUs of different species was found to be 9.3–66.5 μM by using microscale thermophoresis. The ability of this peptide to activate different CSUs does not correlate well with its binding ability (Kd) to these CSUs, thus implying that key interactions by specific residues is more important than binding ability in promoting enzymatic reactions. The high sequence similarity of the peptide ΔN14–ΔC89 to RSUs across species hints that this peptide represents the minimum activation motif in RSU and that it regulates all AHASs.
Luminescent Platinum(II) Complexes of 1,3‐Bis(N‐alkylbenzimidazol‐ 2′‐yl)benzene‐Type Ligands with Potential Applications in Efficient Organic Light‐Emitting Diodes
Authors: Lam Elizabeth Suk‐Hang , Tsang Daniel Ping‐Kuen , Lam Wai Han , Tam Anthony Yiu‐Yan , Chan Mei‐Yee , Wong Wing‐Tak , Yam Vivian Wing‐Wah 
Published: March 2013

AbstractA series of luminescent platinum(II) complexes of tridentate 1,3‐bis(N‐alkylbenzimidazol‐2′‐yl)benzene (bzimb) ligands has been synthesized and characterized. One of these platinum(II) complexes has been structurally characterized by X‐ray crystallography. Their electrochemical, electronic absorption, and luminescence properties have been investigated. Computational studies have been performed on this class of complexes to elucidate the origin of their photophysical properties. Some of these complexes have been utilized in the fabrication of organic light‐emitting diodes (OLEDs) by using either vapor deposition or spin‐coating techniques. Chloroplatinum(II)bzimb complexes that are functionalized at the 5‐position of the aryl ring, [Pt(R‐bzimb)Cl], not only show tunable emission color but also exhibit high current and external quantum efficiencies in OLEDs. Concentration‐dependent dual‐emissive behavior was observed in multilayer OLEDs upon the incorporation of pyrenyl ligand into the Pt(bzimb) system. Devices doped with low concentrations of the complexes gave rise to white‐light emission, thereby representing a unique class of small‐molecule, platinum(II)‐based white OLEDs.
K⋅⋅⋅F/O Interactions Bridge Copper(I) Fluorinated Alkoxide Complexes and Facilitate Dioxygen Activation
Authors: Lum June S. , Tahsini Laleh , Golen James A. , Moore Curtis , Rheingold Arnold L. , Doerrer Linda H. 
Published: March 2013

AbstractSeven E[Cu(OR)2] copper(I) complexes (E=K+, {K(18C6)}+ (18C6=[18]crown‐6), or Ph4P+; R=C4F9, CPhMeF2, and CMeMeF2) have been prepared and their reactivity with O2 studied. The K[Cu(OR)2] species react with O2 in a copper‐concentration‐dependent manner such that 2:1 and 3:1 Cu/O2 adducts are observed manometrically at −78 °C. Analogous reactivity with O2 is not observed with the {K(18C6)}+ or Ph4P+ derivatives. Solution conductivity data demonstrate that these K[Cu(OR)2] complexes do not behave as 1:1 electrolytes in solution. The K+ ions induce aggregation of multiple [Cu(OR)2]− units through K⋅⋅⋅F/O interactions and thereby effect irreversible O2 reduction by multiple Cu centers. Bond valence analyses for the potassium cations confirm the dominance of the fluorine interactions in the coordination spheres of K+ ions. Intramolecular hydroxylation of ligand aryl and alkyl CH bonds is observed. Nucleophilic reactivity with CO2 is observed for the oxygenated Cu complexes and a CuII carbonate has been isolated and characterized.
Silicateins—A Novel Paradigm in Bioinorganic Chemistry: Enzymatic Synthesis of Inorganic Polymeric Silica
Authors: Müller Werner E. G. , Schröder Heinz C. , Burghard Zaklina , Pisignano Dario , Wang Xiaohong 
Published: March 2013

AbstractThe inorganic matrix of the siliceous skeletal elements of sponges, that is, spicules, is formed of amorphous biosilica. Until a decade ago, it remained unclear how the hard biosilica monoliths of the spicules are formed in sponges that live in a silica‐poor (<50 μM) aquatic environment. The following two discoveries caused a paradigm shift and allowed an elucidation of the processes underlying spicule formation; first the discovery that in the spicules only one major protein, silicatein, exists and second, that this protein displays a bio‐catalytical, enzymatic function. These findings caused a paradigm shift, since silicatein is the first enzyme that catalyzes the formation of an inorganic polymer from an inorganic monomeric substrate. In the present review the successive steps, following the synthesis of the silicatein product, biosilica, and resulting in the formation of the hard monolithic spicules is given. The new insight is assumed to open new horizons in the field of biotechnology and also in biomedicine.
An Imine‐Based Molecular Cage with Distinct Binding Sites for Small and Large Alkali Metal Cations
Authors: Schouwey Clément , Scopelliti Rosario , Severin Kay 
Published: March 2013

AbstractThe synthesis of a cylindrical, imine‐based cage composed of two trimeric metallamacrocycles is described. The cage acts as a heterotopic receptor for alkali metal cations. The small cations Li+, Na+, and K+ bind to the outside of the cage with good selectivity for Li+, whereas the larger cations Rb+ and Cs+ are bound inside the cage to form unusual π complexes with a good selectivity for Cs+. Negative heterotopic cooperativity between the two binding sites is observed. The complexation of Cs+ is associated with a color change, which enables the cage to be used as a specific sensor for Cs+.
Alterations in the motor neuron–renshaw cell circuit in the Sod1G93A mouse model
Authors: Wootz Hanna , FitzSimons‐Kantamneni Eileen , Larhammar Martin , Rotterman Travis M. , Enjin Anders , Patra Kalicharan , André Elodie , Van Zundert Brigitte , Kullander Klas , Alvarez Francisco J. 
Published: March 2013

AbstractMotor neurons become hyperexcitable during progression of amyotrophic lateral sclerosis (ALS). This abnormal firing behavior has been explained by changes in their membrane properties, but more recently it has been suggested that changes in premotor circuits may also contribute to this abnormal activity. The specific circuits that may be altered during development of ALS have not been investigated. Here we examined the Renshaw cell recurrent circuit that exerts inhibitory feedback control on motor neuron firing. Using two markers for Renshaw cells (calbindin and cholinergic nicotinic receptor subunit alpha2 [Chrna2]), two general markers for motor neurons (NeuN and vesicular acethylcholine transporter [VAChT]), and two markers for fast motor neurons (Chondrolectin and calcitonin‐related polypeptide alpha [Calca]), we analyzed the survival and connectivity of these cells during disease progression in the Sod1G93A mouse model. Most calbindin‐immunoreactive (IR) Renshaw cells survive to end stage but downregulate postsynaptic Chrna2 in presymptomatic animals. In motor neurons, some markers are downregulated early (NeuN, VAChT, Chondrolectin) and others at end stage (Calca). Early downregulation of presynaptic VAChT and Chrna2 was correlated with disconnection from Renshaw cells as well as major structural abnormalities of motor axon synapses inside the spinal cord. Renshaw cell synapses on motor neurons underwent more complex changes, including transitional sprouting preferentially over remaining NeuN‐IR motor neurons. We conclude that the loss of presynaptic motor axon input on Renshaw cells occurs at early stages of ALS and disconnects the recurrent inhibitory circuit, presumably resulting in diminished control of motor neuron firing. © 2012 Wiley Periodicals, Inc.
Cubic Mesoporous Silica (SBA‐16) Prepared Using Butanol as the Co‐Surfactant: A General Matrix for the Preparation of FeCo‐SiO2 Nanocomposites
Authors: Carta Daniela , Bullita Salvatore , Casula Maria F. , Casu Alberto , Falqui Andrea , Corrias Anna 
Published: March 2013

AbstractA mesoporous ordered cubic Im3m silica (SBA‐16) characterized by a three dimensional cage‐like structure of pores was used as a host matrix for the preparation of a series of FeCo‐SiO2 nanocomposites with different alloy loading and composition by the wet impregnation method. The mesoporous structure of the SBA‐16‐type support, prepared according to a versatile sol‐gel templated synthetic method, which makes use of n‐butanol as a co‐surfactant, is stable during the treatments necessary to obtain the final nanocomposites, as pointed out by low‐angle X‐Ray diffraction, transmission electron microscopy, and N2 physisorption at 77 K. Wide‐angle X‐ray diffraction shows that upon reduction at 800 °C, FeCo nanocrystals (6–7 nm) with the typical bcc structure are formed and energy‐dispersive X‐ray spectroscopy analysis, performed by scanning transmission electron microscopy on one of the samples, shows that the Fe/Co atomic ratio in the alloy nanoparticles is very close to the expected value of two. Electron tomography was used for the first time to gain evidence on the highly interconnected mesoporous structure of SBA‐16 and the arrangement of the nanoparticles within the matrix. It was found that spherical alloy nanocrystals with narrow size distribution are homogeneously distributed throughout the mesoporous matrix and that the resulting FeCo‐SiO2 nanocomposite material displays superparamagnetic behavior with high strength dipolar interactions, as expected for particles with a large magnetic moment.
Structure and Immunological Activity of the Lipopolysaccharide Isolated from the Species Alkalimonas delamerensis
Authors: Silipo Alba , Di Lorenzo Flaviana , Fazio Luigi Lembo , Paciello Ida , Sturiale Luisa , Palmigiano Angelo , Parrilli Michelangelo , Grant William D. , Garozzo Domenico , Lanzetta Rosa , Bernardini Maria Lina , Molinaro Antonio 
Published: March 2013

AbstractWe have defined the complete structure and assessed the biological activity of the lipopolysaccharide (LPS) from Alkalimonas delamerensis, an alkaliphilic bacterium isolated from soda lakes in China and East Africa. The structural determination, which was achieved by the use of chemical, spectroscopic and spectrometric approaches, indicates a novel Rough type lipopolysaccharide that is rich in negatively charged groups in the lipid A inner core region. The proinflammatory activity of the pure lipopolysaccharide has also been defined by testing the LPS as a stimulant in human HEK293 cells, which express the CD14/MD2/TLR4 complex (HEK293‐hTLR4), and in bone marrow‐derived macrophages.
Noniterative interface reconstruction algorithms for volume of fluid method
Authors: Vignesh T.G. , Bakshi Shamit 
Published: March 2013

SUMMARYIn this paper, noniterative interface reconstruction algorithms for volume of fluid (VOF) method are presented. Analytical expressions are derived to determine the coefficients of the curve to achieve a noniterative reconstruction procedure. Static interface reconstruction tests of standard geometries like circle and ellipse are performed. The noniterative algorithm based on Piecewise Linear Interface Calculation from an earlier work is found to reconstruct the VOF value within machine tolerance. Two piecewise continuous algorithms are also proposed in this work, which ensures C0 continuity. The first algorithm, namely, Piecewise Continuous Linear Interface Calculation (PCLIC), uses piecewise continuous linear segments to approximate the interface. The second algorithm uses piecewise continuous quadratic curve and is named as Piecewise Continuous Quadratic Interface Calculation. PCLIC is seen to achieve machine tolerance in reconstructing the VOF value. Piecewise Continuous Quadratic Interface Calculation is found to give a more accurate estimate of the length of the interface than Piecewise Linear Interface Calculation and PCLIC. Copyright © 2013 John Wiley & Sons, Ltd.
Using ammonium pore water profiles to assess stoichiometry of deep remineralization processes in methanogenic continental margin sediments
Authors: Burdige David J. , Komada Tomoko 
Published: March 2013

AbstractIn many continental margin sediments, a deep reaction zone exists which is separated from remineralization processes near the sediment surface. Here, methane diffuses upward to a depth where it is oxidized by downwardly diffusing sulfate. However, the methane sources that drive this anaerobic oxidation of methane (AOM) in the sulfate‐methane transition zone (SMT) may vary among sites. In particular, these sources can be thought of as either (i) “internal” sources from in situ methanogenesis (regardless of where it occurs in the sediment column) that are ultimately coupled to organic matter deposition and burial, or (ii) “external” sources such as hydrocarbon reservoirs derived from ancient source rocks, or deeply buried gas hydrates, both of which are decoupled from contemporaneous organic carbon deposition at the sediment surface. Using a modeling approach, we examine the relationship between different methane sources and pore water sulfate, methane, dissolved inorganic carbon (DIC), and ammonium profiles. We show that pore water ammonium profiles through the SMT represent an independent “tracer” of remineralization processes occurring in deep sediments that complement information obtained from profiles of solutes directly associated with AOM and carbonate precipitation, i.e., DIC, methane, and sulfate. Pore water DIC profiles also show an inflection point in the SMT based on the type of deep methane source and the presence/absence of accompanying upward DIC fluxes. With these results, we present a conceptual framework which illustrates how shallow pore water profiles from continental margin settings can be used to obtain important information about remineralization processes and methane sources in deep sediments.
Reciprocal Peer Coaching: A Critical Contributor to Implementing Individual Leadership Plans
Authors: Goldman Ellen , Wesner Marilyn , Karnchanomai Ornpawee 
Published: March 2013

AbstractBillions of dollars are spent annually on programs to develop organizational leaders, yet the effectiveness of these programs is poorly understood. Scholars advise that value is enhanced by the development of individual leadership plans at program completion, followed by implementation experience with subsequent coaching and reflection. The literature discusses coaching on specific skills in individual plans; research is lacking regarding coaching's value for the individual plan implementation process as a whole. In addition, there is scant literature concerning the use of reciprocal peer coaching in leadership development. This article presents the findings of research aimed at understanding the experience of individuals who completed a leadership development program, prepared individual leadership plans at completion, and then engaged in a process that included reciprocal peer coaching to help them implement their plans. The major contributions of the study concern the importance of the support structure provided, the nature of the benefits identified from giving as well as receiving coaching, and the specification of a transformational learning process regarding both the implementation of individual leadership plans and engagement in reciprocal peer coaching. While the study was conducted in a medical educational setting, the findings have implications for leadership development programs in other areas of education, as well as other organizational settings.
Invited Reaction: The Strategic Value of HRD in Lean Strategy Implementation
Authors: Yorks Lyle , Barto Jody 
Published: March 2013

AbstractThis study by Meera Alagaraja and Toby Egan provides a case study of a Lean strategy implementation in which HRD was an integrated part of the process and offers a model that can give direction for both future research and strategic advocacy on behalf of HRD practice. The case is actually more a study of the importance of cross‐functional and corporate‐SBU collaboration in implementing strategic business plans than of HRD per se. The HRD contribution is contextualized in the strategic implementation process. As such, it offers a comprehensive and contextualized perspective on the process through which the strategic aspirations of HRD can potentially be realized in practice. That said, there is a broader story that needs to be known in order to contextualize and further understand how the study fits into the broader discussion about SHRD.