bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation, Structural Analyses and Biological Activity Assays against Chronic Lymphocytic Leukemia of Two Novel Cytochalasins — Sclerotionigrin A and B
Authors: Petersen Lene , Bladt Tanja , Dürr Claudia , Seiffert Martina , Frisvad Jens , Gotfredsen Charlotte , Larsen Thomas
Published: July 2014

Two new cytochalasins, sclerotionigrin A (1) and B (2) were isolated together with the known proxiphomin (3) from the filamentous fungus Aspergillus sclerotioniger. The structures and relative stereochemistry of 1 and 2 were determined based on comparison with 3, and from extensive 1D and 2D NMR spectroscopic analysis, supported by high resolution mass spectrometry (HRMS). Compounds 2 and 3 displayed cytotoxic activity towards chronic lymphocytic leukemia cells in vitro, with 3 being the most active.
The Hydractinia echinata Test-System. III: Structure-Toxicity Relationship Study of Some Azo-, Azo-Anilide, and Diazonium Salt Derivatives
Authors: Chicu Sergiu , Munteanu Melania , Cîtu Ioana , Şoica Codruta , Dehelean Cristina , Trandafirescu Cristina , Funar-Timofei Simona , Ionescu Daniela , Simu Georgeta
Published: July 2014

Structure-toxicity relationships for a series of 75 azo and azo-anilide dyes and five diazonium salts were developed using Hydractinia echinata (H. echinata) as model species. In addition, based on these relationships, predictions for 58 other azo-dyes were made. The experimental results showed that the measured effectiveness Mlog(1/MRC50) does not depend on the number of azo groups or the ones corresponding to metobolites, but it is influenced by the number of anilide groups, as well as by the substituents’ positions within molecules. The conformational analysis pointed out the intramolecular hydrogen bonds, especially the simple tautomerization of quinoidic (STOH) or aminoidic (STNH2) type. The effectiveness is strongly influenced by the “push-pull” electronic effect, specific to two hydroxy or amino groups separated by an azo moiety (double alternate tautomery, (DAT), to the –COOH or –SO3H groups which are located in ortho or para position with respect to the azo group. The levels of the lipophylic/hydrophilic, electronic and steric equilibriums, pointed out by the Mlog(1/MRC50) values, enabled the calculation of their average values Clog(1/MRC50) (“Köln model”), characteristic to one derivative class (class isotoxicity). The azo group reduction and the hydrolysis of the amido/peptidic group are two concurrent enzymatic reactions, which occur with different reaction rates and mechanisms. The products of the partial biodegradation are aromatic amines. No additive or synergic effects are noticed among them.
Glutaraldehyde Cross-Linking of Immobilized Thermophilic Esterase on Hydrophobic Macroporous Resin for Application in Poly(ε-caprolactone) Synthesis
Authors: Wang Min , Shi Hui , Wu Di , Han Haobo , Zhang Jianxu , Xing Zhen , Wang Shuang , Li Quanshun
Published: July 2014

The immobilized thermophilic esterase from Archaeoglobus fulgidus was successfully constructed through the glutaraldehyde-mediated covalent coupling after its physical adsorption on a hydrophobic macroporous resin, Sepabeads EC-OD. Through 0.05% glutaraldehyde treatment, the prevention of enzyme leaching and the maintenance of catalytic activity could be simultaneously realized. Using the enzymatic ring-opening polymerization of ε-caprolactone as a model, effects of organic solvents and reaction temperature on the monomer conversion and product molecular weight were systematically investigated. After the optimization of reaction conditions, products were obtained with 100% monomer conversion and Mn values lower than 1010 g/mol. Furthermore, the cross‑linked immobilized thermophilic esterase exhibited an excellent operational stability, with monomer conversion values exceeding 90% over the course of 12 batch reactions, still more than 80% after 16 batch reactions.
Identifying Practical Solutions to Meet America’s Fiber Needs: Proceedings from the Food & Fiber Summit
Authors: Mobley Amy , Jones Julie , Rodriguez Judith , Slavin Joanne , Zelman Kathleen
Published: July 2014

Fiber continues to be singled out as a nutrient of public health concern. Adequate intakes of fiber are associated with reduced risk for cardiovascular disease, cancer, diabetes, certain gastrointestinal disorders and obesity. Despite ongoing efforts to promote adequate fiber through increased vegetable, fruit and whole-grain intakes, average fiber consumption has remained flat at approximately half of the recommended daily amounts. Research indicates that consumers report increasingly attempting to add fiber-containing foods, but there is confusion around fiber in whole grains. The persistent and alarmingly low intakes of fiber prompted the “Food & Fiber Summit,” which assembled nutrition researchers, educators and communicators to explore fiber’s role in public health, current fiber consumption trends and consumer awareness data with the objective of generating opportunities and solutions to help close the fiber gap. The summit outcomes highlight the need to address consumer confusion and improve the understanding of sources of fiber, to recognize the benefits of various types of fibers and to influence future dietary guidance to provide prominence and clarity around meeting daily fiber recommendations through a variety of foods and fiber types. Potential opportunities to increase fiber intake were identified, with emphasis on meal occasions and food categories that offer practical solutions for closing the fiber gap.
Inner FoV Stitching of Spaceborne TDI CCD Images Based on Sensor Geometry and Projection Plane in Object Space
Authors: Tang Xinming , Hu Fen , Wang Mi , Pan Jun , Jin Shuying , Lu Gang
Published: July 2014

High-quality inner FoV (Field of View) stitching is currently a prerequisite step for photogrammetric processing and application of image data acquired by spaceborne TDI CCD cameras. After reviewing the technical development in the issue, we present an inner FoV stitching method based on sensor geometry and projection plane in object space, in which the geometric sensor model of spaceborne TDI CCD images is used to establish image point correspondence between the stitched image and the TDI CCD images, using an object-space projection plane as the intermediary. In this study, first, the rigorous geometric sensor model of the TDI CCD images is constructed. Second, principle and implementation of the stitching method are described. Third, panchromatic high-resolution (HR) images of ZY-1 02C satellite and triple linear-array images of ZY-3 satellite are utilized to validate the correctness and feasibility of the method. Fourth, the stitching precision and geometric quality of the generated stitched images are evaluated. All the stitched images reached the sub-pixel level in precision. In addition, the geometric models of the stitched images can be constructed with zero loss in geometric precision. Experimental results demonstrate the advantages of the method for having small image distortion when on-orbit geometric calibration of satellite sensors is available. Overall, the new method provide a novel solution for inner FoV stitching of spaceborne TDI CCD images, in which all the sub-images are projected to the object space based on the sensor geometry, performing indirect image geometric rectification along and across the target trajectory. At present, this method has been successfully applied in the daily processing system for ZY-1 02C and ZY-3 satellites.
A Tool to Evaluate Different Renovation Alternatives with Regard to Sustainability
Authors: Mjörnell Kristina , Boss Anna , Lindahl Markus , Molnar Stefan
Published: July 2014

In Sweden and in other countries, building owners are encouraged to help reduce energy consumption, both in order to contribute to national energy saving goals and, in terms of their own interests, to reduce the costs of heating and operation of the building. However, it is important to pursue the most optimal strategy available so as to achieve cost-effective energy usage while simultaneously maintaining excellent indoor environments, without sacrificing the architectural quality or negatively affecting the environment. Building managers often do not have the time or expertise required to make a proper evaluation of the available options before making a final decision. Renovation measures are often considered in the light of repaying investments in a short time rather than taking into account life cycle costs, despite the fact that a thoughtful, comprehensive renovation is often more cost-effective in the long run. This article presents a systematic approach for evaluating different renovation alternatives based on sustainability criteria. A methodology has been developed to evaluate different renovation alternatives from environmental, economic, and social perspectives. The benefit of using the proposed methodology is that building managers who face a major renovation work are provided with a clear comparison between the different renovation options, viewed from a sustainability perspective, this may facilitate, in the long run, a culture in which renovation measures which involve marginally increased costs, but are seen to lead to significant environmental and social benefits, will be considered and carried out.
A promising cellulose-based polyzwitterion with pH-sensitive charges
Authors: Elschner Thomas , Heinze Thomas
Published: July 2014

A novel polyzwitterion possessing weak ionic groups could be efficiently synthesized from cellulose phenyl carbonate. Polyanion, polycation, and polyzwitterion are accessible by orthogonal removal of protecting groups. The molecular structure was proofed by FTIR- and NMR spectroscopy. Characteristic properties of the cellulose derivatives, e.g., acid dissociation constants, isoelectric point and complexation, were investigated by potentiometric titration (pH), nephelometry, rheology and dynamic light-scattering. The formation of pH-responsive interpolyelectrolyte complexes applying polydiallyldimethylammonium chloride was preliminary studied.
The land crab Johngarthia planata (Stimpson, 1860) (Crustacea, Brachyura, Gecarcinidae) colonizes human-dominated ecosystems in the continental mainland coast of Mexico
Authors: Perger Robert
Published: July 2014

The land crab Johngarthia planata (Stimpson, 1860) has been reported from the Baja California Peninsula and several oceanic islands in the Eastern Pacific as well as inshore islands of the Mexican, Costa Rican and Colombian coast. However, the species has not been observed on the continental mainland, as it is likely that the high diversity of terrestrial predators/competitors make the establishment of mainland populations nearly impossible. In this contribution, several new records of this species that have been observed in urban areas along the continental Pacific coast of Mexico are reported. These records demonstrate that the presence of humans does not necessarily have a negative impact on land crab species. Indeed, the presence of humans may actually discourage the presence of native crab predators/competitors and hence increase the likelihood of a successful mainland settlement of land crab species that are otherwise island and peninsula restricted. The presence of J. planata is ecologically relevant for coastal forests because gecarcinid crabs significantly influence plant recruitment and J. planata is considerably larger than the mainland species Gecarcinus quadratus.
Clonotypic Composition of the CD4+ T Cell Response to a Vectored Retroviral Antigen Is Determined by Its Speed
Authors: Thorborn Georgina , Ploquin Mickaël J. , Eksmond Urszula , Pike Rebecca , Bayer Wibke , Dittmer Ulf , Hasenkrug Kim J. , Pepper Marion , Kassiotis George
Published: July 2014

The mechanisms whereby different vaccines may expand distinct Ag-specific T cell clonotypes or induce disparate degrees of protection are incompletely understood. We found that several delivery modes of a model retroviral Ag, including natural infection, preferentially expanded initially rare high-avidity CD4+ T cell clonotypes, known to mediate protection. In contrast, the same Ag vectored by human adenovirus serotype 5 induced clonotypic expansion irrespective of avidity, eliciting a predominantly low-avidity response. Nonselective clonotypic expansion was caused by relatively weak adenovirus serotype 5–vectored Ag presentation and was reproduced by replication-attenuated retroviral vaccines. Mechanistically, the potency of Ag presentation determined the speed and, consequently, completion of the CD4+ T cell response. Whereas faster completion retained the initial advantage of high-avidity clonotypes, slower completion permitted uninhibited accumulation of low-avidity clonotypes. These results highlighted the importance of Ag presentation patterns in determining the clonotypic composition of vaccine-induced T cell responses and ultimately the efficacy of vaccination.
Continuity of Care in the Training Environment: Anesthesiology Residency in the Ambulatory Surgery Setting
Authors: Munro Jonathan L. T. , DiPompeo Christine M. , Kress Natalie E. , McDonald Timothy B.
Published: July 2014

Background

Anesthesiology residents acquire clinical skills and acumen primarily from experience providing anesthesia for procedural cases, with prior preparation maximizing learning. Ambulatory surgery and associated management styles create fluid anesthesiology staffing—reducing predictability for learners and disrupting continuity of care.

Objective

This prospective, observational study aimed to quantify anesthesia personnel changes in the operating rooms of a single teaching hospital.

Methods

For a 5-week period, Monday through Friday, we recorded the surgical schedule on the prior evening. After the day of surgery, tracking software provided a list of cases performed. We completed electronic health record review for each case, recorded the actual anesthesiology personnel involved, and compared that to the personnel originally scheduled. We also recorded the occurrence of any permanent transitions of care within a case, the type of operation, and the anesthesia start and end times.

Results

Anesthesia providers included 47 residents and 32 attending physicians. The study period included 1285 scheduled cases, 55% (n  =  711) of which were started and finished by the originally scheduled resident and attending physician. Including canceled cases (126 of 1285, 10%) and added cases (207 of 1366, 15%), residents started anesthetics on patients and with attending physicians assigned to them from the day before 54% of the time. Transitions of care occurred in 19% (260 of 1366) of the cases.

Conclusions

Anesthesiology residents prepare for many procedures that do not eventuate and frequently start other cases without prior opportunity for preparation and study. Transitions of care further reduce continuity of care and fragment supervision.
Relationship among soil parameters, tree nutrition and site index of Pinus radiata D. Don in Asturias, NW Spain
Authors: Afif-Khouri E. , Camara Obregon M. A. , Oliveira-Prendes J. A. , Gorgoso-Valera J. J. , Canga-Libano E.
Published: July 2014

Se estudia en 38 parcelas de 0,1 ha cada una las propiedades del suelo que más influyen en el índice de sitio (IS) de plantaciones de Pinus radiata D. Don de 10 a 54 años de edad y en su estado nutricional en Asturias, considerando diferentes variables de masa y distinto material parental. Los suelos estudiados presentaron un carácter fuertemente ácido, alto contenido de materia orgánica, relación C/N elevada, bajo contenido en bases y P disponible extraído por el método de Mehlich 3 (PM3). Las deficiencias más extendidas fueron en K y P, observándose en algunas parcelas deficiencias en Mg y Ca. Sin embargo, las concentraciones en N fueron siempre superiores al nivel crítico. El P foliar se correlacionó positivamente con la capacidad de intercambio catiónico efectiva y con PM3. El IS osciló entre 9,5 y 28,8 m y estuvo positivamente correlacionado con la concentración de P en acículas y con el K intercambiable en el suelo en todas las parcelas y negativamente con la pendiente y el N foliar en las parcelas desarrolladas sobre cuarcitas y areniscas respectivamente. Los resultados revelan la importancia de la elección del sitio y la necesidad de fertilización en los programas de reforestación.
Cultural Diversity and Paleomobility in the Andean Middle Horizon: Radiogenic Strontium Isotope Analyses in the San Pedro De Atacama Oases of Northern Chile
Authors: Knudson Kelly J. , Torres-Rouff Christina
Published: July 2014

Despite a long history of research, interactions between the Tiwanaku polity of the Andean Middle Horizon (ca.A.D. 500-1100) and the San Pedro de Atacama oases of northern Chile remain controversial. Here, we investigate Middle Horizon interactions through an isotopic identification of the geographic origins of individuals buried in San Pedro de Atacama cemeteries and present the largest radiogenic strontium isotope dataset generated, to date, for the Andes. For individuals in Middle Horizon San Pedro de Atacama cemeteries ofCasa Parroquial, Coyo Oriental, Coyo-3, Larache, Quitor-5, Solcor-3, Solcor Plaza, Solor-3, and Tchecar Túmulo Sur, mean tooth enamel and bone87Sr/86Sr = .70834 ± .00172 (2σ, n = 273). Overall, the mean87Sr/86Sr values from Middle Horizon San Pedro de Atacama cemeteries support the idea that interactions between Atacameños and inhabitants of other regions varied by ayllu, an Andean kin-based community structure, with some ayllus incorporating individuals with a wider variety of geographic origins than others. When our interpretations of the radiogenic strontium isotope data are contextualized with analyses of mortuary behavior and recent biodistance analyses, we argue that the San Pedro de Atacama oases appear to be have been inhabited by culturally and biologically diverse groups, rather than by large numbers of colonists from the Tiwanaku capital and the Lake Titicaca Basin.
The pseudo GTPase CENP-M drives human kinetochore assembly
Authors: Basilico Federica , Maffini Stefano , Weir John R , Prumbaum Daniel , Rojas Ana M , Zimniak Tomasz , De Antoni Anna , Jeganathan Sadasivam , Voss Beate , van Gerwen Suzan , Krenn Veronica , Massimiliano Lucia , Valencia Alfonso , Vetter Ingrid R , Herzog Franz , Raunser Stefan , Pasqualato Sebastiano , Musacchio Andrea
Published: July 2014

Kinetochores, multi-subunit complexes that assemble at the interface with centromeres, bind spindle microtubules to ensure faithful delivery of chromosomes during cell division. The configuration and function of the kinetochore–centromere interface is poorly understood. We report that a protein at this interface, CENP-M, is structurally and evolutionarily related to small GTPases but is incapable of GTP-binding and conformational switching. We show that CENP-M is crucially required for the assembly and stability of a tetramer also comprising CENP-I, CENP-H, and CENP-K, the HIKM complex, which we extensively characterize through a combination of structural, biochemical, and cell biological approaches. A point mutant affecting the CENP-M/CENP-I interaction hampers kinetochore assembly and chromosome alignment and prevents kinetochore recruitment of the CENP-T/W complex, questioning a role of CENP-T/W as founder of an independent axis of kinetochore assembly. Our studies identify a single pathway having CENP-C as founder, and CENP-H/I/K/M and CENP-T/W as CENP-C-dependent followers.
Joining Scientists and Stakeholders in Regional Earth System Modeling
Authors: Rosenzweig Bernice , Vörösmarty Charles , Gutowski William , Steiner Allison L.
Published: July 2014

The 19th Conference of the Parties (COP19) to the United Nations Framework Committee on Climate Change concluded in November 2013 with limited progress toward reducing global emissions of greenhouse gases. However, while international negotiations on climate change have stalled, regional initiatives are quietly starting to play an important role in the fight to subvert catastrophic climate change. Examples include the Regional Greenhouse Gas Initiative to reduce emissions in the northeast United States and the ClimAct Regions Project, which aims to reduce greenhouse emissions in 60 regions and provinces of Europe.
Mineralogy of the MSL Curiosity landing site in Gale crater as observed by MRO/CRISM
Authors: Seelos Kimberly D. , Seelos Frank P. , Viviano‐Beck Christina E. , Murchie Scott L. , Arvidson Raymond E. , Ehlmann Bethany L. , Fraeman Abigail A.
Published: July 2014

Orbital data acquired by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) and High Resolution Imaging Science Experiment instruments on the Mars Reconnaissance Orbiter (MRO) provide a synoptic view of compositional stratigraphy on the floor of Gale crater surrounding the area where the Mars Science Laboratory (MSL) Curiosity landed. Fractured, light‐toned material exhibits a 2.2 µm absorption consistent with enrichment in hydroxylated silica. This material may be distal sediment from the Peace Vallis fan, with cement and fracture fill containing the silica. This unit is overlain by more basaltic material, which has 1 µm and 2 µm absorptions due to pyroxene that are typical of Martian basaltic materials. Both materials are partially obscured by aeolian dust and basaltic sand. Dunes to the southeast exhibit differences in mafic mineral signatures, with barchan dunes enhanced in olivine relative to pyroxene‐containing longitudinal dunes. This compositional difference may be related to aeolian grain sorting.
A new approach to discriminate dinoflagellate from diatom blooms from space in the East China Sea
Authors: Shang Shaoling , Wu Jingyu , Huang Bangqin , Lin Gong , Lee Zhongping , Liu James , Shang Shaoping
Published: July 2014

Dinoflagellate and diatom blooms often occur in the East China Sea (ECS) during spring and summer. Some of the dinoflagellate blooms are toxic, resulting in widespread economic damage. In order to mitigate the negative impacts, remote‐sensing methods that can effectively and accurately discriminate between bloom types are demanded for early warning and continuous monitoring of bloom events at large scales. An in situ bio‐optical data set collected from diatom and dinoflagellate blooming waters indicates that the two types of blooms exhibited distinctive differences in the shapes and magnitudes of remote‐sensing reflectance (Rrs). The ratio of in situ measured Rrs spectral slopes at two spectral ranges (443–488 and 531–555 nm, bands available with the moderate resolution imaging spectrometer (MODIS) sensor), abbreviated as BI (representing bloom index), was found effective in differentiating dinoflagellates from diatoms. Reflectance model simulations, which were carried out using in situ and algal culture data as input, provided consistent results. A classification approach for separating dinoflagellate from diatom blooms in the ECS was then developed: When fluorescence line height (FLH) is doubled over the background level and total absorption coefficient at 443 nm ≥ 0.5 m−1, if 0.0
BI
0.3, it suggests a dinoflagellate bloom; if 0.3
BI
1.0, it suggests a diatom bloom. Finally, the approach was applied to MODIS measurements over the ECS, and a series of diatom and dinoflagellate bloom events during April–June 2005 and 2011 were successfully identified, suggesting that the proposed approach is generally valid for the ECS.
LYSOZYME AND DEFENSE PEPTIDES AS SUPPRESSORS OF PHENOLOXIDASE ACTIVITY IN Galleria mellonella
Authors: Zdybicka‐Barabas Agnieszka , Mak Paweł , Jakubowicz Teresa , Cytryńska Małgorzata
Published: July 2014

The prophenoloxidase (proPO) cascade supplies quinones and other reactive compounds for melanin formation, protein cross‐linking, hemolymph coagulation, and killing of microbial invaders as well as parasites. The high cytotoxicity of the generated compounds requires a strict control of the activation of the proPO system and phenoloxidase (PO) activity to minimize damage to host tissues and cells. The PO activity in hemolymph of Escherichia coli challenged Galleria mellonella larvae increased, with a temporal drop 1 h after the challenge, reaching the highest level 24 h after the challenge. In the present study, a potential role of G. mellonella defense peptides and lysozyme in controlling the proPO system was investigated. The effects of purified defense peptides (anionic peptides 1 and 2, cecropin D‐like peptide, Galleria defensin, proline‐rich peptides 1 and 2) and lysozyme were analyzed. Four compounds, namely lysozyme, Galleria defensin, proline‐rich peptide 1, and anionic peptide 2, decreased the hemolymph PO activity considerably, whereas the others did not affect the enzyme activity level. Our results indicate that these hemolymph factors could play multiple and distinct roles in the insect immune response.
Towards Reassigning the Rare AGG Codon in Escherichia coli
Authors: Zeng Yu , Wang Wei , Liu Wenshe R.
Published: July 2014

The rare AGG codon in Escherichia coli has been reassigned to code non‐canonical amino acids (ncAAs) by using the PylRS‐${{\rm tRNA}{{{\rm Pyl}\hfill \atop {\rm CCU}\hfill}}}$ pair. When Nε‐alloc‐lysine was used as a PylRS substrate, almost quantitative occupancy of Nε‐alloc‐lysine at an AGG codon site was achieved in minimal medium. ncAAs can be potentially incorporated at the AGG codon with varying efficiencies, depending on their activities towards corresponding enzymes. As AGG is a sense codon, the approach reported here resolves the typical low ncAA incorporation issue that has been associated with ncAA mutagenesis and therefore allows bulk preparation of proteins with site‐selectively incorporated ncAAs for applications such as therapeutic protein production.
Protein Arginine N‐Methyltransferase Substrate Preferences for Different Nη‐Substituted Arginyl Peptides
Authors: Thomas Dylan , Koopmans Timo , Lakowski Ted M. , Kreinin Helmi , Vhuiyan Mynol I. , Sedlock Shona A. , Bui Jennifer M. , Martin Nathaniel I. , Frankel Adam
Published: July 2014

Protein arginine N‐methyltransferases (PRMTs) catalyze methyl‐group transfer from S‐adenosyl‐L‐methionine onto arginine residues in proteins. In this study, modifications were introduced at the guanidine moiety of a peptidyl arginine residue to investigate how changes to the PRMT substrate can modulate enzyme activity. We found that peptides bearing Nη‐hydroxy or Nη‐amino substituted arginine showed higher apparent kcat values than for the monomethylated substrate when using PRMT1, whereas this catalytic preference was not observed for PRMT4 and PRMT6. Methylation by compromised PRMT1 variants E153Q and D51N further supports the finding that the N‐hydroxy substitution facilitates methyl transfer by tuning the reactivity of the guanidine moiety. In contrast, Nη‐nitro and Nη‐canavanine substituted substrates inhibit PRMT activity. These findings demonstrate that methylation of these PRMT substrates is dependent on the nature of the modification at the guanidine moiety.
The Scaffold Protein IscU Retains a Structured Conformation in the FeS Cluster Assembly Complex
Authors: Yan Robert , Kelly Geoff , Pastore Annalisa
Published: July 2014

IscU and IscS are two essential proteins in the machine responsible for the biogenesis of iron–sulfur clusters, prosthetic groups that are involved in several essential functions. The scaffold protein IscU is the temporary acceptor of the cluster that results when the protein forms a 110 kDa complex with the desulfurase IscS. In the absence of zinc, which stabilises the folded state, IscU is present in solution in equilibrium between a structured and an unstructured form. It has been suggested that IscS preferentially binds unstructured IscU, although crystal structures indicate otherwise. To learn more about the IscS–IscU complex, we have used advanced solution NMR techniques to observe directly the state of fold of IscS‐bound IscU. We present unambiguous evidence that IscU is folded in the complex and that the unstructured form does not bind to IscS. Our data correlate with several observations and explain an IscU‐related pathology.
Response and Adaptation of Escherichia coli to Suppression of the Amber Stop Codon
Authors: Wang Qian , Sun Tingting , Xu Jianfeng , Shen Zhouxin , Briggs Steven P. , Zhou Demin , Wang Lei
Published: July 2014

Some extant organisms reassign the amber stop codon to a sense codon through evolution, and suppression of the amber codon with engineered tRNAs has been exploited to expand the genetic code for incorporating non‐canonical amino acids (ncAAs) in live systems. However, it is unclear how the host cells respond and adapt to such amber suppression. Herein we suppressed the amber codon in Escherichia coli with an orthogonal tRNA/synthetase pair and cultured the cells under such a pressure for about 500 generations. We discovered that E. coli quickly counteracted the suppression with transposon insertion to inactivate the orthogonal synthetase. Persistent amber suppression evading transposon inactivation led to global proteomic changes with a notable up‐regulation of a previously uncharacterized protein (YdiI) for which we identified an unexpected function of expelling plasmids. These results should be valuable for understanding codon reassignment in genetic code evolution and for improving the efficiency of ncAA incorporation.
Synthesis and Electrocatalytic Properties of Uniform Palladium Nanocubes by using Graphene Oxide as Surfactant and Support
Authors: Qin Yu‐ling , Wang Jian‐wei , Zhang Lei‐lei , Wang Li‐min
Published: July 2014

Pd nanocubes dispersed on graphene oxide were prepared by the reduction of PdCl42−. In this method,graphene oxideactedasboth surfactant and support.The as‐prepared Pd nanocubes/graphene oxidecatalyst exhibited higher electrocatalytic activity and stability than a commercial Pd/C catalyst for methanol and formic acid oxidation.
Enantioselective Synthesis of (R)‐2‐Arylpropanenitriles Catalysed by Ene‐Reductases in Aqueous Media and in Biphasic Ionic Liquid–Water Systems
Authors: Brenna Elisabetta , Crotti Michele , Gatti Francesco G. , Manfredi Alessia , Monti Daniela , Parmeggiani Fabio , Santangelo Sara , Zampieri Davila
Published: July 2014

The enantioselective reduction of α‐methylene nitrile derivatives catalysed by ene‐reductases affords the corresponding (R)‐2‐arylpropanenitriles with high conversion values. The reaction is investigated either in aqueous medium (with an organic cosolvent or by loading the substrate onto hydrophobic resins) or in a biphasic ionic liquid–water system. The use of ionic liquids, herein with isolated ene‐reductases, is found to improve the work‐up and the substrate recovery method. The synthetic manipulation of the final chiral nitrile derivatives indicates how this biocatalysed method can be exploited for the preparation of a wide range of chiral compounds.
Selective N‐Alkylation of Indoles with α,β‐Unsaturated Compounds Catalyzed by a Monomeric Phosphate
Authors: Sunaba Hanako , Kamata Keigo , Mizuno Noritaka
Published: July 2014

Catalytic N‐alkylation of indoles is challenging because the N1 nitrogen atoms are inert toward electrophilic reagents. Herein, an organic‐solvent‐soluble alkylammonium salt of a simple monomeric phosphate ion, [PO4]3−, with a high charge density acts as an efficient homogeneous catalyst for selective N‐alkylation of indoles with α,β‐unsaturated compounds. For the reaction of indole with ethyl acrylate, the turnover number reached up to 36 and the turnover frequency was 216 h−1; these values are the highest among those reported for base‐mediated systems so far. In the presence of [PO4]3− ions, various combinations of nitrogen nucleophiles (ten examples) and α,β‐unsaturated compounds (four examples) were efficiently converted to the desired N‐alkylated products in high yields. NMR and IR spectroscopies showed formation of the indolyl anion through the activation of indole by the [PO4]3− ion, which plays an important role in the present N‐alkylation.
A 3D Nanoporous Ni–Mo Electrocatalyst with Negligible Overpotential for Alkaline Hydrogen Evolution
Authors: Wang Yuhang , Zhang Guoxin , Xu Wenwen , Wan Pengbo , Lu Zhiyi , Li Yaping , Sun Xiaoming
Published: July 2014

The front cover artwork is provided by the group of Prof. Xiaoming Sun and Prof. Pengbo Wan at Beijing University of Chemical Technology (PR China). The image shows a Ni–Mo electrocatalyst for the hydrogen evolution reaction (HER). It is revealed that the performance of the fabricated 3D Ni–Mo electrocatalyst with negligible overpotential, high current density, ultrahigh activity, and durable stability for alkaline HER, challenges that of Pt catalysts. Read the full text of the article at 10.1002/celc.201402089.
Effects of Salinity on the Photosynthesis of Two Poaceous Halophytes
Authors: Zhou Changfang , Shen Wenyan , Lu Changmei , Wang Hanxing , Xiao Yan , Zhao Yongqiang , An Shuqing
Published: July 2014

To explore the difference of C4and C3photosynthetic pathways in responding to high salinity and its potential role in determining vegetation zonation in coastal saltmarshes, two Poaceous halophytes, C4Spartina alternifloraand C3Phragmites australis, were studied with different salinities. The results showed that proper salinities were required for both species to maintain optimal photosynthesis. The maximal net assimilation rates ofS. alternifloraandP. australisappeared with 400 and 100 mmol L−1NaCl, respectively. Both species exhibited similar responses of stomatal conductance towards the set salinities, and chlorophyll contents inP. australiswere even promoted by 100–400 mmol L−1NaCl. Although no significant changes in the maximal quantum yield of photosystem II were found in either species treated by NaCl, instant quantum yield of photosystem II ofP. australiswas significantly decreased, whereas that ofS. alternifloraincreased. We suggest that the zonation betweenS. alternifloraandP. australisis not exclusively caused by the CO2‐concentrating mechanism of the C4pathway and stomatal conductance is not a restricting factor for either species. It might be that the electron transfer from photosystem II and the energy use efficiency being limited in the C3P. australisgrown under high salinity.
Effects of Connection Mode and Hydraulic Retention Time on Wastewater Pollutants Removal in Constructed Wetland Microcosms
Authors: Ren Li‐Jun , Xu Li‐Li , Zhang Yu‐Yuan , Pan Wei , Yin Sheng‐Lai , Zhou Yan , Yu Lu‐Ji , Chen Yu‐Shun , An Shu‐Qing
Published: July 2014

A series of multi‐stage connected constructed wetland (CW) microcosms were studied at different hydraulic retention times (HRTs) to determine the effects of the wetland connection mode and HRT on wastewater pollutants removal efficiency. The connection modes included series (Ser), parallel (Par), Ser–Par, and Par–Ser, while HRTs of 1, 2, 3, 4, and 5 h were studied. By integrating three stages of vertical‐ and horizontal‐flow CWs, the pollutant removal processes were separated into different steps. The results showed that the Ser–Par mode had the highest total nitrogen removal efficiency (45.2%) at an HRT of 3 h and the highest total phosphorus removal efficiency (74.6%) at HRT = 5 h. In terms of chemical oxygen demand (COD), the Par system had the highest removal efficiency (75.9%) at HRT = 4 h. The highest removal efficiency for NH4+‐N (68.4%) was observed in the Ser system at HRT = 4 h. Overall, coupled systems at the 4 h HRT showed optimal removal efficiency where 75.9% of COD and 68.4% of NH4+‐N were removed, respectively. Our results suggest multi‐stage coupled CW with appropriate HRT can be a comprehensive and effective method for urban wastewater treatment.
Combined Ozone and Biological Treatment of Oak Wood Leachate
Authors: Svensson Henric , Hansson Henrik , Hogland William
Published: July 2014

In the present study, we investigated the possibility of treating oak wood leachate with a combined ozone and biological treatment. Wood leachate is characterized by high amounts of organic carbon and is reported as being toxic to aquatic organisms. Ozone was used as a pre‐treatment before using aerobic degradation. The biological treatment was applied for seven days and evaluated using head‐space respirometry. Target pollutant in this investigation was polyphenols in combination with more general parameters, such as chemical oxygen demand (COD), total organic carbon (TOC) and colour. A custom made bubble column reactor was used, 1.5 L of wood leachate was exposed to 0–4 g/L of ozone, corresponding to a specific ozone dose between 0.7–7 g/L O3/g of initial COD. Oak wood leachate was found to be easily degraded by ozone, with >90% of polyphenols degraded. COD was degraded by 73%, TOC by 61% and colour by 97% by ozone. Furthermore, a positive correlation between biodegradation and ozone pre‐treatment was found.
The Effects of Conformational Constraints in the Polyamine Moiety of Philanthotoxins on AMPAR Inhibition
Authors: Franzyk Henrik , Grzeskowiak John W. , Tikhonov Denis B. , Jaroszewski Jerzy W. , Mellor Ian R.
Published: July 2014

Philanthotoxin‐433 (PhTX‐433) is a known potent inhibitor of ionotropic glutamate receptors, and analogues have been synthesised to identify more potent and selective antagonists. Herein we report the synthesis of four PhTXs with a cyclopropane moiety introduced into their polyamine chain, and their inhibition of an α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA) receptor subtype by using two‐electrode voltage‐clamp assays on Xenopus oocytes expressing the GluA1flop subunit. All analogues were found to be more potent than PhTX‐343, with trans‐cyclopropyl‐PhTX‐343 being the most potent (∼28‐fold) and cis‐cyclopropyl‐PhTX‐343 least potent (∼4‐fold). Both cis‐ and trans‐cyclopropyl‐PhTX‐444 had intermediate potency (both ∼12‐fold). Molecular modelling indicates that a cyclopropane moiety confers a favourable steric constraint to the polyamine part, but this is compromised by a cis conformation due to enhanced intramolecular folding. Elongated PhTX‐444 analogues alleviate this to some extent, but optimal positioning of the amines is not permitted.
Cobalt‐Phosphate‐Assisted Photoelectrochemical Water Oxidation by Arrays of Molybdenum‐Doped Zinc Oxide Nanorods
Authors: Lin Yan‐Gu , Hsu Yu‐Kuei , Chen Ying‐Chu , Lee Bing‐Wei , Hwang Jih‐Shang , Chen Li‐Chyong , Chen Kuei‐Hsien
Published: July 2014

We report the first demonstration of cobalt phosphate (Co‐Pi)‐assisted molybdenum‐doped zinc oxide nanorods (Zn1−xMoxO NRs) as visible‐light‐sensitive photofunctional electrodes to fundamentally improve the performance of ZnO NRs for photoelectrochemical (PEC) water splitting. A maximum photoconversion efficiency as high as 1.05 % was achieved, at a photocurrent density of 1.4 mA cm−2. More importantly, in addition to achieve the maximum incident photon to current conversion efficiency (IPCE) value of 86 %, it could be noted that the IPCE of Zn1−xMoxO photoanodes under monochromatic illumination (450 nm) is up to 12 %. Our PEC performances are comparable to those of many oxide‐based photoanodes in recent reports. The improvement in photoactivity of PEC water splitting may be attributed to the enhanced visible‐light absorption, increased charge‐carrier densities, and improved interfacial charge‐transfer kinetics due to the combined effect of molybdenum incorporation and Co‐Pi modification, contributing to photocatalysis. The new design of constructing highly photoactive Co‐Pi‐assisted Zn1−xMoxO photoanodes enriches knowledge on doping and advances the development of high‐efficiency photoelectrodes in the solar‐hydrogen field.
Efficient Conversion of Polyamides to ω‐Hydroxyalkanoic Acids: A New Method for Chemical Recycling of Waste Plastics
Authors: Kamimura Akio , Ikeda Kosuke , Suzuki Shuzo , Kato Kazunari , Akinari Yugo , Sugimoto Tsunemi , Kashiwagi Kohichi , Kaiso Kouji , Matsumoto Hiroshi , Yoshimoto Makoto
Published: July 2014

An efficient transformation of polyamides to ω‐hydroxy alkanoic acids was achieved. Treatment of nylon‐12 with supercritical MeOH in the presence of glycolic acid gave methyl ω‐hydroxydodecanoate in 85 % yield and the alcohol/alkene selectivity in the product was enhanced to up to 9.5:1. The use of 18O‐enriched acetic acid for the reaction successfully introduced an 18O atom at the alcoholic OH group in the product. This strategy may provide a new and economical solution for the chemical recycling of waste plastics.
Phenothiazinedioxide‐Conjugated Sensitizers and a Dual‐TEMPO/Iodide Redox Mediator for Dye‐Sensitized Solar Cells
Authors: Lin Ryan Yeh‐Yung , Chu Te‐Chun , Chen Ping‐Wei , Ni Jen‐Shyang , Shih Pei‐Chieh , Chen Yung‐Chung , Ho Kuo‐Chuan , Lin Jiann T.
Published: July 2014

Metal‐free dyes containing a phenothiazinedioxide entity in the spacer were synthesized. The best conversion efficiency (7.47 %) of the dye‐sensitized solar cell (DSSC) by using new sensitizers with chenodeoxycholic acid as a co‐adsorbent and the I−/I3− electrolyte reached over 90 % of that of the standard N719‐based cell (8.10 %). A new type of ionic liquid containing the nitroxide radical (NO.) and iodide was successfully synthesized and applied to the DSSCs. If the I−/I3− electrolyte was replaced with a dual redox electrolyte, that is, a TEMPO (2,2,6,6‐tetramethylpiperidin‐1‐oxyl) derivative with a dangling imidazolium iodide entity, the cell exhibited a high open‐circuit voltage of 0.85 V and a cell efficiency of 8.36 %.
The Mechanisms of Oxygen Reduction and Evolution Reactions in Nonaqueous Lithium–Oxygen Batteries
Authors: Cao Ruiguo , Walter Eric D. , Xu Wu , Nasybulin Eduard N. , Bhattacharya Priyanka , Bowden Mark E. , Engelhard Mark H. , Zhang Ji‐Guang
Published: July 2014

A fundamental understanding of the mechanisms of both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) in nonaqueous lithium–oxygen (Li–O2) batteries is essential for the further development of these batteries. In this work, we systematically investigate the mechanisms of the ORR/OER reactions in nonaqueous Li–O2 batteries by using electron paramagnetic resonance (EPR) spectroscopy, using 5,5‐dimethyl‐pyrroline N‐oxide as a spin trap. The study provides direct verification of the formation of the superoxide radical anion (O2.−) as an intermediate in the ORR during the discharge process, while no O2.− was detected in the OER during the charge process. These findings provide insight into, and an understanding of, the fundamental reaction mechanisms involving oxygen and guide the further development of this field.
Electrochemical Performance of Planar Solid Oxide Fuel Cell (SOFC) Stacks: From Repeat Unit to Module
Authors: Guan Wanbing , Wang Wei Guo
Published: July 2014

The electrochemical performance of a solid oxide fuel cell (SOFC) manufactured stack module (MSM) subjected to thermal cycling sintering is generally lower than that of a unit cell tested directly. By characterizing a 10‐cell stack assembled from a 5‐cell testing stack and a 5‐cell manufactured short stack module, the main factors that affect the electrochemical performance were determined to be the contact uniformity and depth between the interconnect and cell cathode covering the total surface. The cathode contact is improved by designing the external pressure on the stack during the manufacturing process; thus, the output power of a 30‐cell MSM from a typical type of anode made from yttria‐stabilized zirconia (YSZ) and lanthanum strontium manganite (LSM), Ni–YSZ/YSZ/LSM, for which the cell reached approximately 750 W power at the working temperature of 800 °C. Futhermore, the 30‐cell MSM shows no degradation during the experiment. The electrochemical performance (herein referring to output power density and operating stability) approaches that of the corresponding unit cell being tested directly.
Electrochemical investigations of carbon‐based conductive coatings for application as anodes in ICCP systems of reinforced concrete structures
Authors: Poltavtseva M. , Ebell G. , Mietz J.
Published: July 2014

Carbon‐based conductive coatings are complex composites, consisting of an organic or inorganic binder and conductive carbon components, for application as anodes in impressed current cathodic protection systems of reinforced concrete structures. The electrochemical properties of three coatings at different humidity and in saturated calcium hydroxide solution were studied by electrochemical methods, such as electrochemical impedance measurement, measuring of open circuit potential over time and galvanostatic polarization. The dissolved organic and inorganic carbons in electrolyte solution were quantified by using a photometric method. The structures of the coatings were investigated before and after the electrochemical tests by microscopy and scanning electron microscope/EDX analysis. The results of the electrochemical impedance measurements show that the tested coatings all have a relatively low resistance, which is between 100 and 200 Ω. The binder and the surface porosity influence the degradation behavior of those coatings. Especially the organic binder reacts with the strong alkaline medium under dissolving of organic carbon.
Metal‐Free Cycloaddition of Internal Alkynes and Multifunctional Azides Under Solvent‐Free Conditions
Authors: Sandmann Benedict , Happ Bobby , Vitz Jürgen , Paulus Renzo M. , Hager Martin D. , Burtscher Peter , Moszner Norbert , Schubert U. S.
Published: July 2014

The synthesis of three different electron‐deficient internal alkynes for the metal‐free 1,3‐dipolar azide–alkyne cycloaddition is shown. The alkynes are polymerized with several multifunctional azides and the reaction enthalpy (ΔH) is investigated by differential scanning calorimetry (DSC). The mechanical properties of the resulting polymers are analyzed using nanoindentation. The polymerization results in hard materials with an E‐modulus of maximum 2.5 GPa, which make them interesting in particular for biomedical applications.

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Scalable Antifouling Reverse Osmosis Membranes Utilizing Perfluorophenyl Azide Photochemistry
Authors: McVerry Brian T. , Wong Mavis C. Y. , Marsh Kristofer L. , Temple James A. T. , Marambio‐Jones Catalina , Hoek Eric M. V. , Kaner Richard B.
Published: July 2014

We present a method to produce anti‐fouling reverse osmosis (RO) membranes that maintains the process and scalability of current RO membrane manufacturing. Utilizing perfluorophenyl azide (PFPA) photochemistry, commercial reverse osmosis membranes were dipped into an aqueous solution containing PFPA‐terminated poly(ethyleneglycol) species and then exposed to ultraviolet light under ambient conditions, a process that can easily be adapted to a roll‐to‐roll process. Successful covalent modification of commercial reverse osmosis membranes was confirmed with attenuated total reflectance infrared spectroscopy and contact angle measurements. By employing X‐ray photoelectron spectroscopy, it was determined that PFPAs undergo UV‐generated nitrene addition and bind to the membrane through an aziridine linkage. After modification with the PFPA‐PEG derivatives, the reverse osmosis membranes exhibit high fouling‐resistance.

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Anatomy of anteromedial thigh perforators: CT‐angiography study
Authors: Visconti Giuseppe , Salgarello Marzia , Visconti Emiliano , Cipriani Antonio , Cina Alessandro , Bonomo Lorenzo
Published: July 2014

The anatomy of perforator for anteromedial thigh (AMT) flap is a very much‐debated issue. In this article, we report AMT perforator vascular anatomy by CT‐Angiography (CTA) evaluation of 68 consecutive healthy thighs. Perforators emergence, caliber, length, course, and source vessel in the central three fifth of the thigh were studied by a virtual coordinate system. A mean 4.94 ± 1.75 perforators per thigh (average length, 2.6 ± 0.99 cm) from superficial femoral artery (SFA) were found, emerging medial and lateral to sartorius muscle. A mean 0.4 ± 0.74 perforators per thigh (average length, 2.45 ± 0.97 cm) branched from rectus femoris artery, of which 80% were emerging lateral to sartorius muscle. A mean 0.62 ± 0.91 perforators per thigh (average length, 3.1 ± 1.23 cm) branched from an unnamed branch of SFA, of which 88% were emerging lateral to the sartorius muscle. Perforators' calibre was inferior to 1–5 mm in 177 perforators (51.6%), between 1.5 and 2 mm in 159 (46.7%), and over 2 mm in 7 (2%). The findings from this study show that AMT region is plenty of reliable perforators with overlapping fascial emergence but branching from three different source arteries. © 2014 Wiley Periodicals, Inc. Microsurgery 35:196–203, 2015.