bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of Volatile Organic Compounds in Human Leukocyte Antigen Heterologous Expression Systems: a Cell's “Chemical Odor Fingerprint”
Authors: Aksenov Alexander A. , Gojova Andrea , Zhao Weixiang , Morgan Joshua T. , Sankaran Shankar , Sandrock Christian E. , Davis Cristina E. 
Published: April 2012

AbstractThe major histocompatibility complex (MHC), or human leukocyte antigen (HLA) gene‐coding region in humans, plays a significant role in infectious disease response, autoimmunity, and cellular recognition. This super locus is essential in mate selection and kin recognition because of the organism‐specific odor which can be perceived by other individuals. However, how the unique MHC genetic combination of an organism correlates with generation of the organism‐specific odor is not well understood. In the present work, we have shown that human B‐cells produce a set of volatile organic compounds (VOCs) that can be measured by GC‐MS. More importantly, our results show that specific HLA alleles are related to production of selected VOCs, and that this leads to a cell‐specific odor “fingerprint”. We used a C1R HLA class I A and B locus negative cell line, along with C1R cell lines that were stably transfected with specific A and B alleles. Our work demonstrates for the first time that HLA alleles can directly influence production of specific odor compounds at the cellular level. Given that the resulting odor fingerprint depends on expression of specific HLA sequences, it may yield information on unique human scent profiles, composition of exhaled breath, as well as immune response states in future studies.
Control over the Chemoselectivity of Pd‐Catalyzed Cyclization Reactions of (2‐Iodoanilino)carbonyl Compounds
Authors: Solé Daniel , Fernández Israel , Sierra Miguel A. 
Published: April 2012

AbstractThe factors that control the chemoselectivity of palladium‐catalyzed cyclization reactions of (2‐iodoanilino)carbonyl compounds have been explored by an extensive experimental computational (DFT) study. It was found that the selectivity of the process, that is, the formation of fused six‐ versus five‐membered rings, can be controlled by the proper selection of the initial reactant, reaction conditions, and additives. Thus, esters or amides produce ketones by a nucleophilic addition process, whereas the addition of PhO− ions leads to the formation of indolines by an α‐arylation reaction. In contrast, the corresponding ketone reactants yield a mixture of both reaction products, the ratio of which depends on the base used, in the presence of phenol. The outcome of the processes can be explained by the formation of a common four‐membered palladacycle intermediate from which the competitive nucleophilic addition and α‐arylation reactions occur. The remarkable effect of phenol in the process, which makes the α‐arylation reaction easier, favored the formation of enol complexes, which are stabilized by an intramolecular hydrogen bond between the hydroxy group of the enol moiety and the oxygen atom of the phenoxy ligand. Moreover, the chemoselectivy of the process can be also controlled by the addition of bidendate ligands that lead to the almost exclusive formation of indoles at expenses of the corresponding alcohols.
Design, Synthesis and Biological Evaluation of Potent Azadipeptide Nitrile Inhibitors and Activity‐Based Probes as Promising Anti‐Trypanosoma brucei Agents
Authors: Yang Peng‐Yu , Wang Min , Li Lin , Wu Hao , He Cynthia Y. , Yao Shao Q. 
Published: April 2012

AbstractTrypanosoma cruzi and Trypanosoma brucei are parasites that cause Chagas disease and African sleeping sickness, respectively. There is an urgent need for the development of new drugs against both diseases due to the lack of adequate cures and emerging drug resistance. One promising strategy for the discovery of small‐molecule therapeutics against parasitic diseases has been to target the major cysteine proteases such as cruzain for T. cruzi, and rhodesain/TbCatB for T. brucei. Azadipeptide nitriles belong to a novel class of extremely potent cysteine protease inhibitors against papain‐like proteases. We herein report the design, synthesis, and evaluation of a series of azanitrile‐containing compounds, most of which were shown to potently inhibit both recombinant cruzain and rhodesain at low nanomolar/picomolar ranges. A strong correlation between the potency of rhodesain inhibition (i.e., target‐based screening) and trypanocidal activity (i.e., whole‐organism‐based screening) of the compounds was observed. To facilitate detailed studies of this important class of inhibitors, selected hit compounds from our screenings were chemically converted into activity‐based probes (ABPs), which were subsequently used for in situ proteome profiling and cellular localization studies to further elucidate potential cellular targets (on and off) in both the disease‐relevant bloodstream form (BSF) and the insect‐residing procyclic form (PCF) of Trypanosoma brucei. Overall, the inhibitors presented herein show great promise as a new class of anti‐trypanosome agents, which possess better activities than existing drugs. The activity‐based probes generated from this study could also serve as valuable tools for parasite‐based proteome profiling studies, as well as bioimaging agents for studies of cellular uptake and distribution of these drug candidates. Our studies therefore provide a good starting point for further development of these azanitrile‐containing compounds as potential anti‐parasitic agents.
Enantiomerically Pure Phosphaalkene–Oxazolines (PhAk‐Ox): Synthesis, Scope and Copolymerization with Styrene
Authors: Dugal‐Tessier Julien , Serin Spencer C. , Castillo‐Contreras Emmanuel B. , Conrad Eamonn D. , Dake Gregory R. , Gates Derek P. 
Published: April 2012

AbstractThe design of a synthetic route to a class of enantiomerically pure phosphaalkene–oxazolines (PhAk‐Ox) is presented. The condensation of a lithium silylphosphide and a ketone (the phospha‐Peterson reaction) was used as the PC bond‐forming step. Attempted condensation of PhC(O)Ox (Ox=CNOCH(iPr)CH2) and MesP(SiMe3)Li gave the unusual heterocycle (MesP)2C(Ph)CN‐(S)‐CH(iPr)CH2O (3). However, PhAk‐Ox (S,E)‐MesPC(Ph)CMe2Ox (1 a) was successfully prepared by treating MesP(SiMe3)Li with PhC(O)CMe2Ox (52 %). To demonstrate the modularity and tunability of the phospha‐Peterson synthesis several other phosphaalkene–oxazolines were prepared in an analogous manner to 1 a: TripPC(Ph)CMe2Ox (1 b; Trip=2,4,6‐triisopropylphenyl), 2‐iPrC6H4PC(Ph)CMe2Ox (1 c), 2‐tBuC6H4PC(Ph)CMe2Ox (1 d), MesPC(4‐MeOC6H4)CMe2Ox (1 e), MesPC(Ph)C(CH2)4Ox (1 f), and MesPC(3,5‐(CF3)2C6H3)C(CH2)4Ox (1 g). To evaluate the PhAk‐Ox compounds as prospective precursors to chiral phosphine polymers, monomer 1 a and styrene were subjected to radical‐initiated copolymerization conditions to afford [{MesPC(Ph)(CMe2Ox)}x{CH2CHPh}y]n (9 a: x=0.13n, y=0.87n; GPC: Mw=7400 g mol−1, PDI=1.15).
Risk Management in Mega Projects
Authors: Meier Peter 
Published: April 2012

AbstractIndustrielle Großprojekte sind mit beträchtlichen technischen und unternehmerischen Risiken verknüpft. Das Projektmanagement schließt ein Risikomanagement mit ein. Die Beurteilung der Risiken ist Teil der Entscheidungen in allen Phasen des Projekts. Das Risikomanagement in Projekten ist weitgehend standardisiert und bedient sich stochastischer Planungsmodelle, die mit Monte‐Carlo‐Rechnungen simuliert werden.
Optimization in Energy: Locally vs Globally Optimal Solutions
Authors: Martin Alexander , Pokutta Sebastian , Schewe Lars 
Published: April 2012

AbstractDie Anwendung von Optimierungsmethoden ist in den letzten Jahren zu einem zentralen Bestandteil eines effizienten Energiemanagements geworden. Kraftwerke müssen beispielsweise optimal gesteuert werden und die Energieproduktion auf variierende Lastprofile angepasst werden. Die Optimierung gewinnt daher in Ergänzung zur Simulation immer mehr an Bedeutung, gerade in Zusammenhang mit ingenieurwissenschaftlichen und energiewirtschaftlichen Fragestellungen. Die wichtigsten Optimierungsmethoden werden aus mathematischer Sicht vorgestellt. An zwei ausgewählten Beispielen wird der Mehrwert moderner mathematischer Verfahren zur Bestimmung von nachweislich guten bzw. global optimalen Lösungen gezeigt.
Der menschlichen Duftchemie auf der Spur
Authors: Natsch Andreas 
Published: April 2012

AbstractKörpergerüche haben im modernen Alltag möglicherweise keine Funktion und werden deshalb mit Deodorants und Antitranspirantien gezielt bekämpft. Die Duftproduktion basiert allerdings auf einem faszinierenden Zusammenspiel zwischen spezifischen Drüsensekreten und einer spezialisierten Flora von Hautbakterien. Die beteiligten chemischen und biochemischen Vorgänge wurden in Forschungsarbeiten der letzten zehn Jahre erstmals im Detail beschrieben: Die Struktur neuer Duftmoleküle und deren Konjugate mit Aminosäuren wurde aufgeklärt und die an der Duftfreisetzung beteiligten Enzyme isoliert. Diese Resultate werfen Fragen nach der evolutionären Bedeutung der menschlichen Körpergerüche auf, eröffnen aber auch neue Wege, gezielt wirkende Deodorants zu entwickeln.
Comparative Molecular Profiling of the PPARα/γ Activator Aleglitazar: PPAR Selectivity, Activity and Interaction with Cofactors
Authors: Dietz Michel , Mohr Peter , Kuhn Bernd , Maerki Hans Peter , Hartman Peter , Ruf Armin , Benz Jörg , Grether Uwe , Wright Matthew B. 
Published: April 2012

AbstractPeroxisome proliferator‐activated receptors (PPARs) are a family of nuclear hormone receptors that control the expression of genes involved in a variety of physiologic processes, through heterodimerization with retinoid X receptor and complex formation with various cofactors. Drugs or treatment regimens that combine the beneficial effects of PPARα and γ agonism present an attractive therapeutic strategy to reduce cardiovascular risk factors. Aleglitazar is a dual PPARα/γ agonist currently in phase III clinical development for the treatment of patients with type 2 diabetes mellitus who recently experienced an acute coronary event. The potency and efficacy of aleglitazar was evaluated in a head‐to‐head comparison with other PPARα, γ and δ ligands. A comprehensive, 12‐concentration dose–response analysis using a cell‐based assay showed aleglitazar to be highly potent, with EC50 values of 5 nM and 9 nM for PPARα and PPARγ, respectively. Cofactor recruitment profiles confirmed that aleglitazar is a potent and balanced activator of PPARα and γ. The efficacy and potency of aleglitazar are discussed in relation to other dual PPARα/γ agonists, in context with the published X‐ray crystal structures of both PPARα and γ.
Synthesis, Characterization, and CO2 Adsorptive Behavior of Mesoporous AlOOH‐Supported Layered Hydroxides
Authors: Chang Yen‐Po , Chen Yu‐Chun , Chang Po‐Hsueh , Chen San‐Yuan 
Published: April 2012

AbstractA novel CO2 solid sorbent was prepared by synthesizing and modifying AlOOH‐supported CaAl layered double hydroxides (CaAl LDHs), which were prepared by using mesoporous alumina (γ‐Al2O3) and calcium chloride (CaCl2) in a hydrothermal urea reaction. The nanostructured CaAl LDHs with nanosized platelets (3–30 nm) formed and dispersed inside the crystalline framework of mesoporous AlOOH (boehmite). By calcination of AlOOH‐supported LDHs at 700 °C, the mesoporous CaAl metal oxides exhibited ordered hexagonal mesoporous arrays or uniform nanotubes with a large surface area of 273 m2 g−1, a narrow pore size distribution of 6.2 nm, and highly crystalline frameworks. The crystal structure of the calcined mesoporous CaAl metal oxides was multiphasic, consisting of CaO/Ca(OH)2, Al2O3, and CaAlO mixed oxides. The mesoporous metal oxides were used as a solid sorbent for CO2 adsorption at high temperatures and displayed a maximum CO2 capture capacity (≈45 wt %) of the sorbent at 650 °C. Furthermore, it was demonstrated that the mesoporous CaAl oxides showed a more rapid adsorption rate (for 1–2 min) and longer cycle life (weight change retention: 80 % for 30 cycles) of the sorbent because of the greater surface area and increased number of activated sites in the mesostructures. A simple model for the formation mechanism of mesoporous metal oxides is tentatively proposed to account for the synergetic effect of CaAl LDHs on the adsorption of CO2 at high temperature.
Bemessung von unbewehrtem Mauerwerk nach EC 6 mit Nationalem Anhang
Authors: Graubner Carl‐Alexander , Schmitt Michael 
Published: April 2012

AbstractDie bauaufsichtliche Einführung der neuen europäischen Normengeneration stellt gerade im Mauerwerksbau Planer und Bauausführende vor neue Herausforderungen. Gegenüber der bisher gültigen DIN 1053‐1 müssen sich Planer und Bauausführende auf teilweise grundlegende Änderungen und Neuerungen im Sicherheitskonzept und in der Nachweisführung einstellen und Erfahrungen sammeln. Gerade bei der Bemessung und für die Ausführung von Mauerwerk waren die Unterschiede in den einzelnen europäischen Staaten groß, sodass gewisse Kompromisse erforderlich wurden. An wichtigen Stellen konnten jedoch die bisher in Deutschland üblichen Regelungen durchgesetzt werden. Dieser Beitrag beschäftigt sich mit den wichtigsten Änderungen von DIN EN 1996 gegenüber DIN 1053‐1 und soll den praxisorientierten Einstieg in den Eurocode 6 ermöglichen.Design of unreinforced Masonry structures according EC 6 including the National Annex. Concerning masonry structures the introduction of the Eurocodes is a major challenge for civil engineers and building contractors especially. In comparison with the current DIN 1053‐1 civil engineers and building contractors have to get used to essential innovations and modifications as well as to gather experience with the new regulations. Especially in design of masonry structures and execution significant differences between the European countries exist and compromises for the harmonization had to be found. Nevertheless important German positions could be inforced. This article points out the most important modifications and provides an easy access to the regulations of Eurocode 6.
Von der Bauproduktenrichtlinie zur Bauproduktenverordnung
Authors: Schneider Bernhard 
Published: April 2012

AbstractIm Juli 2013 wird die neue europäische Bauproduktenverordnung in Kraft treten. Sie löst die Bauproduktenrichtlinie ab, die bislang die rechtliche Grundlage der CE‐Kennzeichnung von Bauprodukten ist. Im Gegensatz zur bisherigen Richtlinie, die eine Umsetzung durch nationale Gesetze erforderte, sichert nun die Rechtsform der Verordnung die unmittelbare und gleiche Wirksamkeit der rechtlichen Regelungen in allen Mitgliedstaaten. Damit erfolgt die CE‐Kennzeichnung europaweit nach einheitlichen Vorgaben. Im deutschen Bauproduktengesetz ist damit im Wesentlichen nur noch zu regeln, welche Stellen die im europäischen Recht vorgesehenen Aufgaben zu erfüllen haben.From Construction Products Directive to Construction Products Regulation – the new European legal framework for construction products. In July 2013 the European Construction Products Regulation will enter into force. The new regulation will replace the Construction Products Directive, which is the legal basis for CE marking of construction products today. In contrast to the current situation the legal form of a regulation ensures the direct and equal applicability of the legal provisions in all Member States. On this basis CE marking will follow uniform rules in the European Union. The German construction products law, the Bauproduktengesetz, remains mainly necessary to define which bodies are competent for the tasks foreseen in the European law.
Untersuchungen zur Verbesserung der mechanischen Eigenschaften von Mauerwerk durch Elastomerlager
Authors: Aldoghaim Eyad 
Published: April 2012

AbstractErdbeben verursachen große Wirtschafts‐ und Gesundheitsprobleme durch das spröde Bauteil‐ und Materialversagen von Lebens‐ und Wohnraum. Unbewehrtes Mauerwerk gehört zur Klasse der Baustoffe, die nur einen begrenzten Erdbebenwiderstand aufweisen, da Bauteile aus Mauerwerk Zugspannungen und Zugkräfte nicht wie Stahlbeton‐ und Stahlbauten aufnehmen können. Aus diesem Grund wurde bereits mit unterschiedlichen Methoden versucht, die Schäden und Probleme durch Verbesserung der Tragfähigkeit von Mauerwerk im Erdbebenfall zu minimieren. Modernes Mauerwerk kann auch als bewehrtes oder eingefasstes Mauerwerk erstellt werden. Der Widerstand kann in bewehrtem Mauerwerk deutlich erhöht werden aufgrund der Aufnahme der Zugspannungen durch die Bewehrung. Durch Einfassung mit Stahlbetonelementen können die Tragfähigkeit sowie der Verbund zu angrenzenden Bauteilen verbessert werden. Weitere praktische Möglichkeiten zur Erhöhung des Widerstands bestehen im Aufbringen von Geweben oder hochfesten Lamellen.In diesem Artikel wird ein ganz anderer Weg beschritten, indem weiche Fugen Spannungsspitzen reduzieren sowie eine höhere Verformbarkeit der Bauteile gewährleisten. Dies bedeutet eine Entwicklung der Mauerwerksstruktur mit einer neuartigen Ausbildung der Mauerwerksfugen, nämlich mit Elastomerlagern und Epoxidharzkleber anstatt des üblichen Dünnbettmörtels.Masonry mechanical properties improvement by means of elastomeric material. As earthquake strikes, the brittle failure of living space may cause considerable economic and health problems. Unreinforced masonry which classified as a building material has a limited earthquake resistance, because it does not possess tensile and tension forces like reinforced concrete and steel. Hence, in the case of earthquake, a variety of methods were conducted in order to minimize problems by improving the load bearing capacity of masonry.Modern masonry can be produced as reinforced or constrained one, wherein its resistance significantly increases because its tensile stresses and forces are carried by the reinforcement. The load bearing capacity of masonry as well as its connection to adjacent components can be improved by constraining masonry with reinforced concrete elements. In addition, the application of high‐strength textile or lamella are other possibilities.In this project, a different approach is carried out. Soft bed‐joints lead to reduce stress‐peaks in units and generate higher ductility in masonry. Therefore, a development in the masonry structure by using a novel design of masonry bed‐joints, namely, elastomeric materials combined with epoxy glue; is better than conventional thin mortar.
Salivary cortisol measurement in developmental research: Where do we go from here?
Authors: Clements Andrea D. 
Published: April 2012

AbstractSalivary cortisol has been measured extensively in developmental research over the last three decades. The purpose of this article is to summarize the contributions to and limitations of salivary cortisol measurement in developmental research and propose future directions for research that includes salivary cortisol measurement. The properties of cortisol, the history of its burgeoning popularity, and the utility and limitations of (a) cortisol as a biological indicator, (b) saliva as a source of cortisol, and (c) various saliva collection methodologies are described. The current state of understanding about what is and is not reliably predictable from cortisol is summarized and the value of salivary cortisol measurement in developmental research is discussed, addressing whether methodology could be driving research design. Recommendations are made for streamlining study design and reporting within developmental research. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 55: 205–220, 2013
Microsatellite variation and genetic structure of brook trout (Salvelinus fontinalis) populations in Labrador and neighboring Atlantic Canada: evidence for ongoing gene flow and dual routes of post‐Wisconsinan colonization
Authors: Pilgrim Brettney L. , Perry Robert C. , Keefe Donald G. , Perry Elizabeth A. , Dawn Marshall H. 
Published: April 2012

AbstractIn conservation genetics and management, it is important to understand the contribution of historical and contemporary processes to geographic patterns of genetic structure in order to characterize and preserve diversity. As part of a 10‐year monitoring program by the Government of Newfoundland and Labrador, Canada, we measured the population genetic structure of the world's most northern native populations of brook trout (Salvelinus fontinalis) in Labrador to gather baseline data to facilitate monitoring of future impacts of the recently opened Trans‐Labrador Highway. Six‐locus microsatellite profiles were obtained from 1130 fish representing 32 populations from six local regions. Genetic diversity in brook trout populations in Labrador (average HE= 0.620) is within the spectrum of variability found in other brook trout across their northeastern range, with limited ongoing gene flow occurring between populations (average pairwise FST= 0.139). Evidence for some contribution of historical processes shaping genetic structure was inferred from an isolation‐by‐distance analysis, while dual routes of post‐Wisconsinan recolonization were indicated by STRUCTURE analysis: K= 2 was the most likely number of genetic groups, revealing a separation between northern and west‐central Labrador from all remaining populations. Our results represent the first data from the nuclear genome of brook trout in Labrador and emphasize the usefulness of microsatellite data for revealing the extent to which genetic structure is shaped by both historical and contemporary processes.
Transition‐Metal‐Catalyzed Cyclization of Alkynals via Oxametallacycle Intermediates
Authors: Tanaka Ken , Tajima Yuki 
Published: April 2012

AbstractThe transition‐metal‐catalyzed cyclization of alkynals viaoxametallacycle intermediates is a useful method for thestereoselective synthesis of cyclic allylic alcohol derivatives. The reductive cyclization reactions are catalyzed by titanium and nickel complexes using organosilanes, organoboranes, and organozincs as reducing agents. The alkylative, arylative, and alkenylative cyclization reactions are catalyzed by nickel complexes using organozincs and alkenylzirconiums. On the other hand, the recently developed rhodium‐catalyzed reductive cyclization reactions of alkynals allow using dihydrogen as a reducing agent without the use of organometalloid and organometallic reagents. Furthermore, very recently, the rhodium‐catalyzed acylative cyclization reactions of alkynals were accomplished by using aldehydes and acyl phosphonates as acylating reagents. Importantly, the use of the rhodium catalysts realized the enantioselective cyclization reactions of alkynals with excellent levels of enantioselection.