bluuebunny/crossref_metadata_2025 huggingface dataset:
Hybrid modeling and receding horizon control of sewer networks
Authors: Joseph‐Duran Bernat , Ocampo‐Martinez Carlos , Cembrano Gabriela
Published: September 2014

In this work, a control‐oriented sewer network model is presented based on a hybrid linear modeling framework. The model equations are described independently for each network element, thus allowing the model to be applied to a broad class of networks. A parameter calibration procedure using data obtained from simulation software that solves the physically based model equations is described and validation results are given for a case study. Using the control model equations, an optimal control problem to minimize flooding and pollution is formulated to be solved by means of mixed‐integer linear or quadratic programming. A receding horizon control strategy based on this optimal control problem is applied to the case study using the simulation software as a virtual reality. Results of this closed‐loop simulation tests show the effectiveness of the proposed approach in fulfilling the control objectives while complying with physical and operational constraints.
Pluto‐Bound Spacecraft Crosses Orbit of Neptune
Authors: Showstack Randy
Published: September 2014

NASA's New Horizons spacecraft, which is en route to explore Pluto and its planetary system in 2015, crossed the orbit of Neptune on 25 August, 25 years to the day after NASA's Voyager 2 flew by Neptune.
NOAA Lists 20 Coral Species as Threatened
Authors: Showstack Randy
Published: September 2014

Twenty coral species have been listed as threatened under the U.S. Endangered Species Act (ESA), the National Oceanic and Atmospheric Administration (NOAA) announced on 27 August. This is NOAA's largest ESA rule making. The coral species include 15 found in the Indo‐Pacific region and 5 that are located in the Caribbean. They join two other Caribbean coral species that NOAA listed as threatened in 2006.
Assessing Approaches for Determination of Liquid Water in Snow
Authors: Eisen Olaf , Schweizer Jürg
Published: September 2014

Scientists with expertise in avalanche formation, remote sensing issues, and other cryospheric matters gathered in Davos, Switzerland, in early April for a workshop on liquid water in snow—the first such meeting since 1982. The focus of this year's workshop, held at the Institute for Snow and Avalanche Research, was to compare different measurement techniques and their accuracy, to discuss current assumptions for modeling liquid water transport and storage in snow, and to gather ideas on how to best obtain good validation and verification data.
Moynier Receives 2013 Hisashi Kuno Award: Citation
Authors: Albarède Francis
Published: September 2014

Once upon a time, in a small town in wonderful Provence known by the name of Manosque, best known today, however, for being home to the international tokamak project, a boy was born to a local couple of chemists and was given the name of Frédéric. These parents decided to give him some education and sent him far away from his native Provence to the Ecole Normale Supérieure de Lyon.
Moynier Receives 2013 Hisashi Kuno Award: Response
Authors: Moynier Frédéric
Published: September 2014

I would like to thank the Volcanology, Geochemistry, and Petrology section for awarding me this prize and all the people who were involved in my nomination and wrote the letters. When Catherine McCammon phoned me to let me know that I was awarded the Kuno Award, I was very surprised at first, and then I felt very honored and lucky. I have been very lucky to have Francis Albarède and Janne Blichert‐Toft as Ph.D. advisors. Without their mentoring, I would not be standing here today. Completing my Ph.D. in this dynamic laboratory was an incredible experience, and I was very fortunate to meet many people who became mentors, collaborators, and friends, among whom I will cite Arnaud Agranier, Pierre Beck, and Toshi Fujii.
Dingwell, Head Receive 2013 N. L. Bowen Award: Citation for Donald B. Dingwell
Authors: Russell Kelly
Published: September 2014

It is my privilege and honor to deliver the citation for Don Dingwell to receive AGU's N. L. Bowen Award. Don's research has profoundly influenced our understanding of the properties of silicate melts, glasses, and magmas and the fundamental control they exert on magmatic, volcanic, and, recently, even on earthquake processes. Don's approach is experimental, and his studies have interrogated melts, glasses, and magmas for their transport, calorimetric, geophysical, and rheological properties, as well as the solubilities of volatile species. These experiments have been elegantly designed to elucidate properties that provide quantitative explanations for volcanic processes. He has a prodigious publication record, including many seminal “must‐read papers,” as evidenced by any bibliometrics you choose. Indeed, his research has changed the very way we communicate about volcanic processes by expanding our vocabulary to include “glass transition” or “melt relaxation.” In many ways, his research career has established what is a new, unique, and expanding line of science—“experimental volcanology.”
Dingwell, Head Receive 2013 N. L. Bowen Award: Citation for James W. Head III
Authors: Wilson Lionel
Published: September 2014

It is my pleasure to present James W. Head III of Brown University as a recipient of the 2013 Bowen Award. A major theme of Jim Head's research career has been the unraveling of the volcanic history of the rocky bodies of the solar system, and he has been an investigator on virtually all of the major international planetary investigation missions. Jim is an excellent observer and interpreter of observations. But more than that, as I have observed over our long history of collaboration, he shares the need to understand the basic physical processes controlling volcanism and to interpret observations in a quantitative, as well as qualitative, way. So in addition to documenting the history of volcanism on silicate planets, Jim has been at the forefront of trying to understand the mechanisms of volcanic eruption processes, on Earth as well as elsewhere.
Dingwell, Head Receive 2013 N. L. Bowen Award: Response
Authors: Head James W.
Published: September 2014

Thank you, Lionel, for your kind words. N. L. Bowen has been an inspiration to me since the first geology course that I took as an incoming freshman at Washington and Lee University. I had to take a science course for distribution requirements, and I discovered geology, where the laboratories were often outdoors and the Earth was your laboratory and inspiration! Geology seemed perfect for me: I could combine my love of the outdoors with an insatiable curiosity about what made things work. I was quickly overwhelmed, however, by the beauty and extreme diversity of rocks and minerals, so much so that it was beginning to seem like yet another foreign language to me. Then one day we discussed N. L. Bowen's reaction series, and it all immediately started to make sense to me. This inspired in me a “systems approach” to understanding complex geologic processes and problems. It also compelled me to try to quantify all of the observations that contributed to understanding geological processes.
A remote sensing technique for measuring forest composition
Authors: Schult Colin
Published: September 2014

When it comes to carbon, energy, water, and nutrient cycling, not all trees are the same. Different species, and even the same species at different phases of life, process these resources in diverse ways.
Pyroxenes can be used to estimate upper mantle water content
Authors: Wendel JoAnna
Published: September 2014

The ocean of water locked in the rocks of Earth's mantle can influence geological processes such as melting and mineral deformation. Traditionally, researchers have used the mineral olivine to study the water in Earth's upper mantle, but evolving technology has offered scientists the ability to use other minerals as well.
Magnetic reconnection at the edge of Uranus's magnetic field
Authors: Balcerak Ernie
Published: September 2014

A new modeling study sheds light on how the magnetosphere of Uranus compares to those of other planets. Magnetospheres around the inner planets Mercury and Earth are primarily driven by the solar wind—the charged particles spewed out from the Sun—through magnetic reconnection, in which the planet's magnetic field lines break and reconnect, releasing energy in the process.
Atmospheric forces drive development of superrotation
Authors: Wendel JoAnna
Published: September 2014

Planetary scientists are still puzzling over how superrotation—when a planet's atmosphere rotates faster than its surface—develops on a small or slowly rotating planet like Venus or Titan. Researchers have previously suggested that a certain kind of atmospheric eddy activity is required to retain the momentum surplus over the equator of a planet, where superrotation develops, but have not yet identified this underlying mechanism.
Processes controlling water vapor in the upper troposphere/lowermost stratosphere: An analysis of 8 years of monthly measurements by the IAGOS‐CARIBIC observatory
Authors: Zahn A. , Christner E. , van Velthoven P. F. J. , Rauthe‐Schöch A. , Brenninkmeijer C. A. M.
Published: September 2014

An extensive set of in situ water vapor (H2O) data obtained by the IAGOS‐CARIBIC passenger aircraft at 10–12 km altitude over 8 years (2005–2013) is analyzed. A multifaceted description of the vertical distribution of H2O from the upper troposphere (UT) via the extratropical tropopause mixing layer (exTL) into the lowermost stratosphere (LMS) is given. Compared to longer‐lived trace gases, H2O is highly variable in the UT and exTL. It undergoes considerable seasonal variation, with maxima in summer and in phase from the UT up to ~4 km above the tropopause. The transport and dehydration pathways of air starting at the Earth's surface and ending at 10–12 km altitude are reconstructed based upon (i) potential temperature (θ), (ii) relative humidity with respect to ice (RHi), and (iii) back trajectories as a function of altitude relative to the tropopause. RHi of an air mass was found to be primarily determined by its temperature change during recent vertical movement, i.e., cooling during ascent/expansion and warming during descent/compression. The data show, with great clarity, that H2O and RHi at 10–12 km altitude are controlled by three dominant transport/dehydration pathways: (i) the Hadley circulation, i.e., convective uplift in the tropics and poleward directed subsidence drying from the tropical tropopause layer with observed RHi down to 2%; (ii) warm conveyor belts and midlatitude convection transporting moist air into the UT with observed RHi usually above 60%; and (iii) the Brewer–Dobson shallow and deep branches with observed RHi down to 1%.
Glycomic Analysis of Glycans Released from Glycoproteins Using Chemical Immobilization and Mass Spectrometry
Authors: Yang Shuang , Zhang Hui
Published: September 2014

Protein glycosylation is one of most common protein modifications and is involved in many biological activities. N‐linked and O‐linked glycosylation not only represent abundant glycan modifications, but also are structurally diverse. Mass spectrometry has emerged as a major method for glycomic analysis. However, glycan extraction from proteins and glycan modification are two critical steps in glycomic analysis of glycans using mass spectrometry. In this protocol, we describe a novel and high‐throughput method for isolation and modification of glycans from glycoproteins using a chemoenzymatic approach on solid‐phase. Proteins are first immobilized to a solid support and unconjugated molecules are washed away; glycans, while still linked to glycoproteins on the solid support, can be treated enzymatically or chemically on solid phase for glycan derivatization. Glycans are then released from the solid support for analysis by mass spectrometry. The procedures outlined are robust and useful for high‐throughput glycomic analysis from complex biological or clinical samples. Curr. Protoc. Chem. Biol. 6:191‐208 © 2014 by John Wiley & Sons, Inc.
Supramolekulare Chemie von Anionen: von der Erkennung zur chemischen Anwendung
Authors: Evans Nicholas H. , Beer Paul D.
Published: September 2014

Seit der Jahrtausendwende fanden bemerkenswerte Fortschritte bei der Bindung und dem Nachweis von Anionen statt, die teilweise von den Erkenntnissen zur Ausnutzung von Wasserstoffbrücken ebenso wie den zuvor selten eingesetzten Anionen‐π‐Wechselwirkungen und Halogenbrücken angetrieben wurden. Die supramolekulare Chemie von Anionen wurde indes substantiell über die Anionenerkennung hinaus weiterentwickelt und umfasst nun verschiedene Disziplinen. Große Fortschritte wurden bei der Synthese von Makrocyclen und ineinandergreifenden molekularen Architekturen mit Anionen als Templaten erzielt, während die Untersuchung von anionischen Transmembrantransportern aus dem Nichts heraus zu einem rasch wachsenden Forschungsgebiet erblühte. Die supramolekulare Chemie der Anionen kam außerdem in verschiedenen Anwendungsbereichen wie der Katalyse, der Ionenextraktion und der Verwendung von Anionen als Impuls für molekulare Systeme zum praktischen Einsatz.
Reprogramming Nonribosomal Peptide Synthetases for “Clickable” Amino Acids
Authors: Kries Hajo , Wachtel Rudolf , Pabst Anja , Wanner Benedikt , Niquille David , Hilvert Donald
Published: September 2014

Nonribosomal peptide synthetases (NRPSs) are multifunctional enzymes that produce a wide array of bioactive peptides. Here we show that a single tryptophan‐to‐serine mutation in phenylalanine‐specific NRPS adenylation domains enables the efficient activation of non‐natural aromatic amino acids functionalized with azide and alkyne groups. The resulting 105‐fold switch in substrate specificity was achieved without appreciable loss of catalytic efficiency. Moreover, the effective communication of the modified A domains with downstream modules in dipeptide synthetases permitted incorporation of O‐propargyl‐L‐tyrosine into diketopiperazines both in vitro and in vivo, even in the presence of competing phenylalanine. Because azides and alkynes readily undergo bioorthogonal click reactions, reprogramming NRPSs to accept non‐natural amino acids that contain these groups provides a potentially powerful means of isolating, labeling, and modifying biologically active peptides.
Nanocrystalline‐Graphene‐Tailored Hexagonal Boron Nitride Thin Films
Authors: Lee Kang Hyuck , Shin Hyeon‐Jin , Kumar Brijesh , Kim Han Sol , Lee Jinyeong , Bhatia Ravi , Kim Sang‐Hyeob , Lee In‐Yeal , Lee Hyo Sug , Kim Gil‐Ho , Yoo Ji‐Beom , Choi Jae‐Young , Kim Sang‐Woo
Published: September 2014

Unintentionally formed nanocrystalline graphene (nc‐G) can act as a useful seed for the large‐area synthesis of a hexagonal boron nitride (h‐BN) thin film with an atomically flat surface that is comparable to that of exfoliated single‐crystal h‐BN. A wafer‐scale dielectric h‐BN thin film was successfully synthesized on a bare sapphire substrate by assistance of nc‐G, which prevented structural deformations in a chemical vapor deposition process. The growth mechanism of this nc‐G‐tailored h‐BN thin film was systematically analyzed. This approach provides a novel method for preparing high‐quality two‐dimensional materials on a large surface.
Photocatalytic Hydrogen Production using Polymeric Carbon Nitride with a Hydrogenase and a Bioinspired Synthetic Ni Catalyst
Authors: Caputo Christine A. , Gross Manuela A. , Lau Vincent W. , Cavazza Christine , Lotsch Bettina V. , Reisner Erwin
Published: September 2014

Solar‐light‐driven H2 production in water with a [NiFeSe]‐hydrogenase (H2ase) and a bioinspired synthetic nickel catalyst (NiP) in combination with a heptazine carbon nitride polymer, melon (CNx), is reported. The semibiological and purely synthetic systems show catalytic activity during solar light irradiation with turnover numbers (TONs) of more than 50 000 mol H2 (mol H2ase)−1 and approximately 155 mol H2 (mol NiP)−1 in redox‐mediator‐free aqueous solution at pH 6 and 4.5, respectively. Both systems maintained a reduced photoactivity under UV‐free solar light irradiation (λ>420 nm).
The Isomerization of Allylrhodium Intermediates in the Rhodium‐Catalyzed Nucleophilic Allylation of Cyclic Imines
Authors: Hepburn Hamish B. , Lam Hon Wai
Published: September 2014

Allylrhodium species generated from potassium allyltrifluoroborates can undergo isomerization by 1,4‐rhodium(I) migration to give more complex isomers, which then react with cyclic imines to provide products with up to three new stereochemical elements. High enantioselectivities are obtained using chiral diene–rhodium complexes.
N‐Heterocyclic Carbene Catalyzed Cyclocondensation of α,β‐Unsaturated Carboxylic Acids: Enantioselective Synthesis of Pyrrolidinone and Dihydropyridinone Derivatives
Authors: Chen Xiang‐Yu , Gao Zhong‐Hua , Song Chun‐Yu , Zhang Chun‐Lin , Wang Zhi‐Xiang , Ye Song
Published: September 2014

The catalytic cyclocondensation of in situ activated α,β‐unsaturated carboxylic acids was developed. N‐heterocyclic carbenes efficiently catalyzed the generation of α,β‐unsaturated acyl azolium intermediates from α,β‐unsaturated carboxylic acids via in situ generated mixed anhydrides for the enantioselective [3+2] and [3+3] cyclocondensation with α‐amino ketones and alkyl(aryl)imines, respectively. The corresponding pyrrolidinones and dihydropyridinones were isolated in good yields with high to excellent enantioselectivities.
Insertion of Nitriles into Zirconocene 1‐aza‐1,3‐diene Complexes: Chemoselective Synthesis of N–H and N‐Substituted Pyrroles
Authors: Yu Shasha , Xiong Meijun , Xie Xin , Liu Yuanhong
Published: September 2014

The direct insertion of nitriles into zirconocene‐1‐aza‐1,3‐diene complexes provides an efficient, chemoselective, and controllable synthesis of N‐H and N‐substituted pyrroles upon acidic aqueous work‐up. The outcome of the reaction (that is, the formation of N‐H or N‐substituted pyrroles) results from the different cyclization patterns, which depend on the relative stability and reactivity of the enamine–imine tautomers formed by hydrolysis of the diazazirconacycles.
Edge Detection of Archaeomagnetic Data: a Study from the City of Pisidia Antiocheia, Turkey
Authors: Ar𝚤soy Muzaffer Özgü
Published: September 2014

Magnetic survey is one of a number of methods used in archaeological geophysics for detecting and mapping archaeological artefacts and features. Recent magnetic instruments have become both faster and more sensitive as a result of technological and industrial developments. Hence, magnetic methods are becoming an accepted part of archaeological projects. Mapping the edges of magnetic sources is a problem of fundamental importance in magnetic interpretation. Commonly used edge‐detection filters are considerably affected by the presence of noise because this requires the computation of horizontal and vertical derivatives of the magnetic data. Archaeomagnetic data are often dominated by large‐amplitude anomalies that mostly originate from the presence of noise and other environmental effects. Prior to application of the edge‐detection filters, an upward continuation of the archaeomagnetic anomaly or low‐pass filtering may be used to reduce environmental effects. Another useful approach is to apply edge‐detection filters to the pseudogravity‐transformed data. This paper compares the results of common edge‐detection filters applied to the original and pseudogravity‐transformed archaeomagnetic data. In the concept of edge detection, the feasibility and capability of the pseudogravity transformation is demonstrated using a real archaeomagnetic dataset from the ancient city of Pisidia Antiocheia in the province of Isparta (central part of Turkey). Copyright © 2014 John Wiley & Sons, Ltd.
Near‐peer teaching strategy in a large human anatomy course: Perceptions of near‐peer instructors
Authors: Reyes‐Hernández Cynthia Guadalupe , Carmona Pulido Juan Manuel , De la Garza Chapa Roberto Isaac , Serna Vázquez Ruth Patricia , Alcalá Briones Ricardo Daniel , Plasencia Banda Perla Marina , Villarreal Silva Eliud Enrique , Jacobo Baca Guillermo , de la Garza Castro Oscar , Elizondo Omaña Rodrigo Enrique , Guzmán López Santos
Published: September 2014

Near‐peer teaching (NPT) is a strategy in which senior students assume the instructor role with junior peers (mentees). Senior students develop unique skills and knowledge through NPT, an experience which extends their learning beyond content mastery. Different teaching modules featuring NPT were utilized in the human anatomy course at the School of Medicine, Autonomous University of Nuevo Leon in Monterrey, Mexico. Modules included: Theory, Clinical Hour, Imaging Anatomy, and Laboratory. The aim of this study was to assess instructor participants' perceptions on the benefits of the NPT strategy in the anatomy classroom. A survey was administered to anatomy course instructors who utilized NPT strategies during winter, fall, and spring semesters of the 2012–2013 school year. A total of 120 instructors were enrolled in the study. There were different perceptions of instructors' roles. Theory and Imaging Anatomy instructors considered themselves to be information providers and resource developers, whereas Clinical Hour and Laboratory instructors saw themselves more as facilitators, role models, and planners. All instructors' opinions on the benefits of NPT were positive. Thus, in this article, the authors find NPT to be a strategy that promotes self‐learning, a vital skill. Anat Sci Educ 8: 189–193. © 2014 American Association of Anatomists.
Exclusive Detection of Sub‐Nanomolar Levels of Palladium(II) in Water: An Excellent Probe for Multiple Applications
Authors: Kumari Namita , Dey Nilanjan , Kumar Krishan , Bhattacharya Santanu
Published: September 2014

A new colorimetric probe has been developed for the detection and estimation of PdII at sub‐nanomolar concentrations. The probe consisted of rhodamine (signaling unit), which was linked with a bis‐picolyl moiety (binding site) through a phenyl ring. PdII induced opening of the spirolactam ring of the probe with the generation of a prominent pink color. The excellent selectivity of the probe towards PdII over Pd0 or RhII ensured its potential utility for the detection of residual palladium contamination in pharmaceutical drugs and in Pd‐catalyzed reactions. The probe showed a “turn‐on” (bright yellow) fluorescence upon the addition of PdII, which made it suitable for the detection of Pd contaminants in mammalian cells.
Dramatic Mechanistic Change in Acid‐Catalyzed Arylation of Azafulleroids Depending on their Ambident N/C Basicity: Formation of Cyclopentene Centered Pentakisadduct
Authors: Ikuma Naohiko , Doi Yuta , Fujioka Koichi , Mikie Tsubasa , Kokubo Ken , Oshima Takumi
Published: September 2014

Azafulleroid, amino‐bridged [5,6]‐open fullerene, has the ambident N/C basicity of the incorporated enamine moiety. Acid‐catalyzed arylation of N‐substituted azafulleroids proceeded via two types of initial N/C protonation to perform monoarylation or 1,4‐bisarylation for the N‐alkyl substituents and shuttlecock‐type pentakisarylation for the N‐phenyl substituent. The dramatic product change was explained by considering the possible mechanism as well as the DFT computational results.
Malaria vaccine candidate antigen targeting the pre‐erythrocytic stage ofPlasmodium falciparumproduced at high level in plants
Authors: Voepel Nadja , Boes Alexander , Edgue Güven , Beiss Veronique , Kapelski Stephanie , Reimann Andreas , Schillberg Stefan , Pradel Gabriele , Fendel Rolf , Scheuermayer Matthias , Spiegel Holger , Fischer Rainer
Published: September 2014

Plants have emerged as low‐cost production platforms suitable for vaccines targeting poverty‐related diseases. Besides functional efficacy, the stability, yield, and purification process determine the production costs of a vaccine and thereby the feasibility of plant‐based production. We describe high‐level plant production and functional characterization of a malaria vaccine candidate targeting the pre‐erythrocytic stage ofPlasmodium falciparum. CCT, a fusion protein composed of three sporozoite antigens (P. falciparumcell traversal protein for ookinetes and sporozoites [PfCelTOS],P. falciparumcircumsporozoite protein [PfCSP], andP. falciparumthrombospondin‐related adhesive protein [PfTRAP]), was transiently expressed by agroinfiltration inNicotiana benthamianaleaves, accumulated to levels up to 2 mg/g fresh leaf weight (FLW), was thermostable up to 80°C and could be purified to >95% using a simple two‐step procedure. Reactivity of sera from malaria semi‐immune donors indicated the immunogenic conformation of the purified fusion protein consisting ofPfCelTOS,PfCSP_TSR,PfTRAP_TSR domains (CCT) protein. Total IgG from the CCT‐specific mouse immune sera specifically recognizedP. falciparumsporozoites in immunofluorescence assays and induced up to 35% inhibition in hepatocyte invasion assays. Featuring domains from three promising sporozoite antigens with different roles (attachment and cell traversal) in the hepatocyte invasion process, CCT has the potential to elicit broader immune responses against the pre‐erythrocytic stage ofP. falciparumand represents an interesting new candidate, also as a component of multi‐stage, multi‐subunit malaria vaccine cocktails.
Systematic review of congenital and acquired portal-systemic shunts in otherwise normal livers
Authors: Matthews T J , Trochsler M I , Bridgewater F H , Maddern G J
Published: September 2014

Background

Portal-systemic shunts (PSSs) are rarely seen in healthy individuals or patients with non-cirrhotic liver disease. They may play an important role in hepatic metabolism as well as in the spread of gastrointestinal metastatic tumours to specific organs. Small spontaneous PSSs may be more common than generally thought. However, epidemiological data are scarce and inconclusive. This systematic review examined the prevalence of reported PSSs and the associated detection methods.

Methods

Literature up to 2011 was reviewed for adult patients with proven congenital or acquired PSSs. Only PSSs in normal livers were analysed for the methods of diagnosis. Eligible studies were identified by searching relevant databases, including PubMed, Embase, MEDLINE and the Cochrane Library. The selection of eligible articles was carried out using predefined inclusion criteria (adult, non-surgical PSS) and a set of search terms that were established before the articles were identified.

Results

Eighty studies were included describing 112 patients with congenital or acquired PSSs. The majority were diagnosed incidentally using Doppler ultrasound imaging and CT.

Conclusion

Congenital and acquired PSSs are rare. They are usually clinically asymptomatic and discovered incidentally by radiological techniques. They may be clinically relevant owing to drug, tumour cell, metabolic and pathogen shunting.
A Sensitive phage‐based capture ELISA for sub‐femtomolar detection of protein variants directly from biological samples
Authors: Williams Stephanie , Schulz Philip , Sierks Michael R.
Published: September 2014

To determine the role of proteins, and in particular protein variants, in human health, it may often be necessary to quantitatively determine the concentration of a specific protein variant present in complex biological samples such as blood, cerebral spinal fluid (CSF), or tissue. Many protein variants are present only at trace levels and therefore a simple assay with very high sensitivity and reliability would greatly facilitate correlation of the presence of particular protein variants with the progression of specific diseases. We have developed a simple phage based capture ELISA system that enables femtomolar or better detection of individual protein variants directly from complex biological samples. The protocol utilizes a capture reagent that selectively recognizes a unique epitope of the protein variant and a phage based detection reagent that binds to a second epitope present in all forms of the target protein. The phage based detection reagent is essentially a self‐assembling nanoparticle consisting of several thousand coat proteins that can each be labeled to amplify the detection signal by several orders of magnitude. Here we demonstrate that we can achieve subfemtomolar detection of individual protein variants that have been implicated in neurodegenerative disease directly from complex tissue homogenates and sera. The ELISA system should facilitate identification of disease specific protein variants or other compounds even when present at trace amounts in samples including blood, CSF, saliva and urine. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 31:289–298, 2015
Piloting the Membranolytic Activities of Peptides with a Self‐organizing Map
Authors: Lin Yen‐Chu , Hiss Jan A. , Schneider Petra , Thelesklaf Peter , Lim Yi Fan , Pillong Max , Koehler Fabian M. , Dittrich Petra S. , Halin Cornelia , Wessler Silja , Schneider Gisbert
Published: September 2014

Antimicrobial peptides (AMPs) show remarkable selectivity toward lipid membranes and possess promising antibiotic potential. Their modes of action are diverse and not fully understood, and innovative peptide design strategies are needed to generate AMPs with improved properties. We present a de novo peptide design approach that resulted in new AMPs possessing low‐nanomolar membranolytic activities. Thermal analysis revealed an entropy‐driven mechanism of action. The study demonstrates sustained potential of advanced computational methods for designing peptides with the desired activity.
Construction of a Chimeric Biosynthetic Pathway for the De Novo Biosynthesis of Rosmarinic Acid in Escherichia coli
Authors: Bloch Sarah E. , Schmidt‐Dannert Claudia
Published: September 2014

Hydroxycinnamic acid esters (HCEs) are widely‐distributed phenylpropanoid‐derived plant natural products. Rosmarinic acid (RA), the most well‐known HCE, shows promise as a treatment for cancer and neurological disorders. In contrast to extraction from plant material or plant cell culture, microbial production of HCEs could be a sustainable, controlled means of production. Through the overexpression of a six‐enzyme chimeric bacterial and plant pathway, we show the de novo biosynthesis of RA, and the related HCE isorinic acid (IA), in Escherichia coli. Probing the pathway through precursor supplementation showed several potential pathway bottlenecks. We demonstrated HCE biosynthesis using three plant rosmarinic acid synthase (RAS) orthologues, which exhibited different levels of HCE biosynthesis but produced the same ratio of IA to RA. This work serves as a proof‐of‐concept for a microbial production platform for HCEs by using a modular biosynthetic approach to access diverse natural and non‐natural HCEs.
Immobilized Transition Metals as Catalysts for Cross‐Couplings in Continuous Flow—A Critical Assessment of the Reaction Mechanism and Metal Leaching
Authors: Cantillo David , Kappe C. Oliver
Published: September 2014

In the not too distant future many industrially important chemicals (including pharmaceuticals) will probably be manufactured using continuous flow technology. For a significant number of synthetic steps involved in these protocols transition metal (mostly palladium)‐catalyzed carbon–carbon or carbon–heteroatom bond forming reactions (“cross‐coupling chemistry”) will play an important role. Designing a process for continuous cross‐coupling chemistry involves either the use of a homogeneous or of a heterogeneous (immobilized) catalyst/ligand system. In the latter case, the catalyst/ligand system is typically in the form of a packed‐bed reactor, through which the reaction mixture is pumped, employing an appropriate temperature regime and residence time. Although this approach has been widely popular during the past 15 years, there is growing evidence that suggests that the use of immobilized transition metal catalysts for performing cross‐coupling chemistry in continuous flow is, in fact, not very practical. As demonstrated in this review, significant leaching of the transition metal out of the packed‐bed catalyst will almost inevitably occur, leading to decreased catalyst activity and contamination of the product with transition metal. This is a consequence of the well‐known fact that the reaction mechanism for these kinds of transformations is (quasi)homogeneous and involves the transformation of a Pd0 species into a (soluble) PdII species. Using an immobilized catalyst in a batch protocol the transient leaching of palladium will not be immediately obvious, as, after completion of the catalytic cycle, Pd0 will typically redeposit onto the support. In contrast, in continuous flow mode, the palladium metal will progressively be “chromatographed” through the packed‐bed catalyst until, ultimately, all palladium will be removed from the support. This effect typically will become only evident when long run experiments are performed. The preferred alternative, in particular for larger scale experiments, is to use a homogeneous (pre)catalyst in combination with an appropriate catalyst recycling technology.
Visible‐Light‐Driven Alcohol Dehydrogenation with a Rhodium Catalyst
Authors: Kagalwala Husain N. , Maurer Andrew B. , Mills Isaac N. , Bernhard Stefan
Published: September 2014

We report the photocatalytic dehydrogenation of alcohols with a Rh catalyst and I− in an acidic medium. The catalyst screening of a structurally diverse family of Rh complexes found [RhIII(dtbbpy)2(OSO2CF3)2](CF3SO3) (Rh7; dtbbpy=4,4′‐di‐tert‐butyl‐2,2′‐bipyridine) to be the best catalyst. All components (Rh7, HI, alcohol, and light) were found to be essential for the dehydrogenation to occur. Under optimal conditions, generation of both H2 and acetone (for isopropyl alcohol) was observed, which increased linearly for 4 days with no significant decrease in activity. The proposed mechanism involves the formation of [RhIII(dtbbpy)2(I)2]+ [Rh7(a)] followed by the generation of photoinduced I3− via a ligand (I−) to metal (RhIII) charge transfer. The resulting RhI species reduces H+ and I3− oxidizes the alcohol, which completes the catalytic cycle. Supporting evidence for the catalytic mechanism was obtained by using UV/Vis spectroscopy, electrospray ionization mass spectrometry, cyclic voltammetry and time‐dependent DFT calculations.
Biosorption of Trivalent Chromium from Wastewater: An Approach towards Green Chemistry
Authors: Kanagaraj James , Senthilvelan Thamizharasan , Panda Ramesh C. , Aravindhan Rathinam , Mandal Asit B.
Published: September 2014

Chromium is one of the metals used in industry that create environmental toxicity and pollution problems. In the present study, chromium in wastewater was removed by a biosorption method using a bacterial culture of Bacillus pumilus. A mathematical model representing the biosorption kinetics was formulated, supporting the Langmuir isotherm for the adsorption of chromium. Fourier transform infrared and scanning electron microscopy studies were used to characterize the adsorption of chromium by the bacterial biomass. The analysis of pollution parameters (chemical oxygen demand, total organic content, total dissolved solid, total suspended solid) suggest a significant reduction of the pollution load. The results show that the method developed here is very effective for the removal of chromium from an aqueous environment.
Numerical Investigation of Three‐Dimensional Bubble Column Flows: A Detached Eddy Simulation Approach
Authors: Masood Rao M. A. , Delgado Antonio
Published: September 2014

Numerical simulations were performed employing detached eddy simulation (DES) in a three‐dimensional transient Euler‐Euler framework for bubble columns, and all the computational fluid dynamics results were compared with a k‐ϵ model and available experimental data. The numerical results are in good agreement with the experiments in predicting the time‐averaged axial velocity and turbulent kinetic energy profiles. The flow‐resolving capabilities of the DES model are highlighted, and it is shown that the DES turbulence model can be efficiently used for simulating flow field and turbulent quantities in the case of bubble columns.
Energy‐Efficient Size Reduction Technology for Wet Fibrous Biomass Treatment in Industrial Biofuel Technologies
Authors: Kratky Lukas , Jirout Tomas
Published: September 2014

Biomass size reduction belongs to the high energy‐consuming operations in industrial biofuel technologies. Its energy requirement actually ranges from hundreds to thousands of kilowatt‐hours per ton of dry biomass. These high energy values are primarily caused by energy demand of disintegrators used for wet fibrous biomass. Therefore, the reduction of this energy requirement could significantly improve the whole process economics. Suitable disintegrators were searched and several potential industrial technologies of mechanical disintegration for wet fibrous biomass with respect to minimum energy demand were designed. Wet wheat straw served as model material to evaluate their energy requirements. The technology with the least energy demand was composed of a new, fully developed retting mill.
Supercapacitive Behavior of Two Glucose‐Derived Microporous Carbons: Direct Pyrolysis versus Hydrothermal Carbonization
Authors: Sevilla Marta , Yu Linghui , Ania Conchi O. , Titirici Maria‐Magdalena
Published: September 2014

The physical and chemical characteristics of activated carbons produced from glucose and hydrothermally carbonized glucose are compared for the first time, as well as their performance as electrodes in supercapacitors with aqueous electrolyte (H2SO4). Both KOH‐activated carbons exhibit similar textural properties, with Brunauer–Emmett–Teller surface areas of ≈1400–1500 m2 g−1 and a pore volume of ≈0.70 cm3 g−1, with the pore size distribution centered in the micropore range. When tested as supercapacitor electrodes, the activated carbon produced from hydrothermally carbonized glucose exhibits a superior rate capability, owing to lower equivalent distributed resistance (being able to work at an ultrahigh discharge current of 90 A g−1), as well as higher specific capacitance (≈240 F g−1 vs. ≈220 F g−1 for the glucose‐derived activated carbon at 0.1 A g−1). Both supercapacitors have excellent robustness, even for a large cell voltage of 1.2 V in 1 M H2SO4.
Isoxazole‐Embedded Allylic Zinc Reagent for the Diastereoselective Preparation of Highly Functionalized Aldol‐Type Derivatives Bearing a Stereocontrolled Quaternary Center
Authors: Klier Lydia , Diène Coura R. , Schickinger Manuel , Metzger Albrecht , Wagner Andreas J. , Karaghiosoff Konstantin , Marek Ilan , Knochel Paul
Published: September 2014

Highly functionalized aldol‐type products bearing a β‐quaternary center and a stereoselectively controlled γ‐hydroxy function are readily prepared by the diastereoselective addition of an allylic zinc reagent embedded in an isoxazole ring to various aromatic and heteroaromatic aldehydes, in the presence of Lewis acids, such as MgCl2 or LaCl3⋅2 LiCl. After reductive cleavage of the NO bond by using Fe, NH4Cl, aldol‐type products bearing a stereocontrolled β‐quaternary center and a γ‐hydroxy group were observed. The benzylic reactivity of the isoxazolylmethylzinc reagent towards other electrophiles, such as acid chlorides, aryl and allylic halides, as well as aldehydes in the presence of BF3⋅OEt2 are also described.
Control of Excitation and Quenching in Multi‐colour Electrogenerated Chemiluminescence Systems through Choice of Co‐reactant
Authors: Barbante Gregory J. , Kebede Noah , Hindson Christopher M. , Doeven Egan H. , Zammit Elizabeth M. , Hanson Graeme R. , Hogan Conor F. , Francis Paul S.
Published: September 2014

We demonstrate a new approach to manipulate the selective emission in mixed electrogenerated chemiluminescence (ECL) systems, where subtle changes in co‐reactant properties are exploited to control the relative electron‐transfer processes of excitation and quenching. Two closely related tertiary‐amine co‐reactants, tri‐n‐propylamine and N,N‐diisopropylethylamine, generate remarkably different emission profiles: one provides distinct green and red ECL from [Ir(ppy)3] (ppy=2‐phenylpyridinato‐C2,N) and a [Ru(bpy)3]2+ (bpy=2,2′‐bipyridine) derivative at different applied potentials, whereas the other generates both emissions simultaneously across a wide potential range. These phenomena can be rationalized through the relative exergonicities of electron‐transfer quenching of the excited states, in conjunction with the change in concentration of the quenchers over the applied potential range.
Photochemical, Electrochemical, and Photoelectrochemical Water Oxidation Catalyzed by Water‐Soluble Mononuclear Ruthenium Complexes
Authors: Li Ting‐Ting , Zhao Wei‐Liang , Chen Yong , Li Fu‐Min , Wang Chuan‐Jun , Tian Yong‐Hua , Fu Wen‐Fu
Published: September 2014

Two mononuclear ruthenium complexes [Ru(H2tcbp)(isoq)2] (1) and [Ru(H2tcbp)(pic)2] (2) (H4tcbp=4,4′,6,6′‐tetracarboxy‐2,2′‐bipyridine, isoq=isoquinoline, pic=4‐picoline) are synthesized and fully characterized. Two spare carboxyl groups on the 4,4′‐positions are introduced to enhance the solubility of 1 and 2 in water and to simultaneously allow them to tether to the electrode surface by an ester linkage. The photochemical, electrochemical, and photoelectrochemical water oxidation performance of 1 in neutral aqueous solution is investigated. Under electrochemical conditions, water oxidation is conducted on the deposited indium‐tin‐oxide anode, and a turnover number higher than 15,000 per water oxidation catalyst (WOC) 1 is obtained during 10 h of electrolysis under 1.42 V vs. NHE, corresponding to a turnover frequency of 0.41 s−1. The low overpotential (0.17 V) of electrochemical water oxidation for 1 in the homogeneous solution enables water oxidation under visible light by using [Ru(bpy)3]2+ (P1) (bpy=2,2′‐bipyridine) or [Ru(bpy)2(4,4′‐(COOEt)2‐bpy)]2+ (P2) as a photosensitizer. In a three‐component system containing 1 or 2 as a light‐driven WOC, P1 or P2 as a photosensitizer, and Na2S2O8 or [CoCl(NH3)5]Cl2 as a sacrificial electron acceptor, a high turnover frequency of 0.81 s−1 and a turnover number of up to 600 for 1 under different catalytic conditions are achieved. In a photoelectrochemical system, the WOC 1 and photosensitizer are immobilized together on the photoanode. The electrons efficiently transfer from the WOC to the photogenerated oxidizing photosensitizer, and a high photocurrent density of 85 μA cm−2 is obtained by applying 0.3 V bias vs. NHE.
Catalytic Asymmetric Synthesis of Alkynyl Aziridines: Both Enantiomers of cis‐Aziridines from One Enantiomer of the Catalyst
Authors: Guan Yong , López‐Alberca Maria P. , Lu Zhenjie , Zhang Yu , Desai Aman A. , Patwardhan Aniruddha P. , Dai Yijing , Vetticatt Mathew J. , Wulff William D.
Published: September 2014

Alkynyl aziridines can be obtained from the catalytic asymmetric aziridination (AZ reaction) of alkynyl imines with diazo compounds in high yields and high asymmetric inductions mediated by a chiral boroxinate or BOROX catalyst. In contrast to the AZ reaction with aryl‐ and alkyl‐substituted imines, alkynyl imines react to give cis‐substituted aziridines with both diazo esters and diazo acetamides. Remarkably, however, the two diazo compounds give different enantiomers of the cis‐aziridine from the same enantiomer of the catalyst. Theoretical considerations of the possible transition states for the enantiogenic step reveal that the switch in enantiomers results from a switch from Si‐face to Re‐face addition to the imine, which in turn is related to a switch from reaction with an E‐imine in the former and a Z‐isomer of the imine in the latter.
Quantitative Insight into the Design of Compounds Recognized by the L‐Type Amino Acid Transporter 1 (LAT1)
Authors: Ylikangas Henna , Malmioja Kalle , Peura Lauri , Gynther Mikko , Nwachukwu Emmanuel O. , Leppänen Jukka , Laine Krista , Rautio Jarkko , Lahtela‐Kakkonen Maija , Huttunen Kristiina M. , Poso Antti
Published: September 2014

L‐Type amino acid transporter 1 (LAT1) is a transmembrane protein expressed abundantly at the blood–brain barrier (BBB), where it ensures the transport of hydrophobic acids from the blood to the brain. Due to its unique substrate specificity and high expression at the BBB, LAT1 is an intriguing target for carrier‐mediated transport of drugs into the brain. In this study, a comparative molecular field analysis (CoMFA) model with considerable statistical quality (Q2=0.53, R2=0.75, Q2 SE=0.77, R2 SE=0.57) and good external predictivity (CCC=0.91) was generated. The model was used to guide the synthesis of eight new prodrugs whose affinity for LAT1 was tested by using an in situ rat brain perfusion technique. This resulted in the creation of a novel LAT1 prodrug with L‐tryptophan as the promoiety; it also provided a better understanding of the molecular features of LAT1‐targeted high‐affinity prodrugs, as well as their promoiety and parent drug. The results obtained will be beneficial in the rational design of novel LAT1‐binding prodrugs and other compounds that bind to LAT1.
Randomized, placebo‐controlled trial of K1 acupoint acustimulation to prevent cisplatin‐induced or oxaliplatin‐induced nausea
Authors: Shen Yehua , Liu Luming , Chiang Joseph S. , Meng Zhiqiang , Garcia M. Kay , Chen Zhen , Peng Huiting , Bei Wenying , Zhao Qi , Spelman Amy R. , Cohen Lorenzo
Published: September 2014

BACKGROUND

Greater than 70% of patients with cancer experience chemotherapy‐induced nausea and vomiting. In the current study, the authors examined the effects of electrostimulation of the K1 acupoint located on the sole of the foot because it is believed to have the potential to control chemotherapy‐induced nausea and vomiting.

METHODS

In this trial, 103 patients diagnosed with primary or metastatic liver cancer were recruited before transcatheter arterial infusion (TAI) of cisplatin or oxaliplatin and randomized to either group A (51 patients who were treated with the antiemetic tropisetron and acustimulation at the K1 acupoint for 20 minutes approximately 1 to 2 hours before TAI on the first day and then daily for the subsequent 5 days) or group B (52 patients who were treated with tropisetron and electrostimulation at a placebo point on the heel). The rate, intensity, and duration of nausea and vomiting were collected at baseline and then daily for 5 days after TAI. Quality of life was assessed daily using the MD Anderson Symptom Inventory and the EuroQoL scale.

RESULTS

No differences were found between groups A and B with regard to the incidence and degree of nausea or vomiting on day 1 or the following 5 days. Patients in group A had better EuroQoL scores compared with patients in group B (72.83 in group A vs 65.94 in group B; P =.04) on day 4 but not on the other days. No group differences were noted at any time point for MD Anderson Symptom Inventory scores.

CONCLUSIONS

Electrostimulation of K1 combined with antiemetics did not result in initial prevention of cisplatin‐induced or oxaliplatin‐induced nausea or vomiting. Cancer 2015;121:84–92. © 2014 American Cancer Society.
Methoxyphenol and Dihydrobenzofuran as Oxidizable Labels for Electrochemical Detection of DNA
Authors: Simonova Anna , Balintová Jana , Pohl Radek , Havran Luděk , Fojta Miroslav , Hocek Michal
Published: September 2014

4‐Hydroxy‐3‐methoxyphenyl (MOP) and 2,3‐dihydrobenzofuran‐5‐yl (DHB) groups were tested as potential new oxidizable labels for electrochemical detection of DNA. The corresponding 5‐aryl‐cytosine and 7‐aryl‐7‐deazaadenine 2′‐deoxyribonucleoside triphosphates (dNTPs) were prepared by the Suzuki coupling of halogenated dNTPs or by triphosphorylation of modified nucleosides, and were incorporated enzymatically into DNA by polymerase. In parallel, the electrochemical behavior of the labeled nucleosides, nucleotides, and DNA was studied to show that most of them give analytically useful signals of oxidation on the carbon electrode. Particularly, MOP appears to be a useful oxidizable DNA label since it offers independent detection of the modified DNA.