bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tandem Gold Self‐Relay Catalysis for the Synthesis of 2,3‐Dihydropyridin‐4(1 H)‐ones: Combination of σ and π Lewis Acid Properties of Gold Salts
Authors: Fustero Santos , Miró Javier , Sánchez‐Roselló María , del Pozo Carlos 
Published: September 2014

AbstractThe dual ability of gold salts to act as π‐ and σ Lewis acids has been exploited in a tandem self‐relay catalysis. Thus, triphenylphosphanegold(I) triflate mediated the intramolecular carbonyl addition of the amide functionality of homoprogargyl amides to a triple bond. The formation of a σ complex of the gold salt with the intermediate oxazine promoted a nucleophilic addition followed by a Petasis–Ferrier rearrangement. This tandem protocol, catalyzed by the same gold salt under the same reaction conditions, gave rise to the efficient synthesis of 2,3‐dihydropyridin‐4‐(1 H)‐ones, which contain a cyclic quaternary α‐amino acid unit. The asymmetric version was performed by generating the starting materials from the corresponding sulfinylimines.
Pseudorotational Landscape of Seven‐Membered Rings: The Most Stable Chair and Twist‐Boat Conformers of ε‐Caprolactone
Authors: Jahn Michaela K. , Dewald David A. , Vallejo‐López Montserrat , Cocinero Emilio J. , Lesarri Alberto , Zou Wenli , Cremer Dieter , Grabow Jens‐Uwe 
Published: September 2014

AbstractThe conformational landscape and ring‐puckering properties of ε‐caprolactone have been analyzed by using microwave spectroscopy and quantum chemical calculations. Two conformers were detected in a supersonic jet expansion, the most stable form being a chair containing the ester group in its rectangular flap. This conformation benefits from reduced CH2 bond eclipsing and angle strain, while π‐electron delocalization in the ester group is increased. The derived effective structure of the chair form satisfactorily agrees with the calculated near‐equilibrium structure. A twist‐boat conformer was also identified (9.4 kJ mol−1 higher in energy at CCSD(T)/aug‐cc‐pVTZ level), and was located in the boat‐twist‐boat pseudorotation cycle of the seven‐membered ring. Three other low‐energy conformers were investigated and characterized in terms of the four puckering coordinates of the seven‐membered ring. Potential interconversions in the four‐dimensional conformation space are also discussed.
Characterisation of Alkane σ‐Complexes
Authors: Young Rowan D. 
Published: September 2014

AbstractAlkane σ‐complexes have evolved from a curious phenomenon to an intermediate of intense interest, fuelling research into the area. Over the last fifteen years, metal alkane complex characterisation has evolved to incorporate reports employing UV/Vis, IR and NMR spectroscopy, and X‐ray and neutron diffractometry. Previously, due to the sparse geometric characterisation of alkane σ‐complexes, assumptions regarding bonding geometries and selectivities were made by comparison to related σ‐complexes, or by analysis of CH activation products. This minireview assembles relevant literature that illuminates the metrics of alkane–metal bonding, and critically analyses the binding mode, selectivity and stability of alkane complexes.
Mechanism of Alkyne Alkoxycarbonylation at a Pd Catalyst with P,N Hemilabile Ligands: A Density Functional Study
Authors: Crawford L. Ellis , Cole‐Hamilton David J. , Drent Eite , Bühl Michael 
Published: September 2014

AbstractA detailed mechanism for alkyne alkoxycarbonylation mediated by a palladium catalyst has been characterised at the B3PW91‐D3/PCM level of density functional theory (including bulk solvation and dispersion corrections). This transformation, investigated via the methoxycarbonylation of propyne, involves a uniquely dual role for the P,N hemilabile ligand acting co‐catalytically as both an in situ base and proton relay coupled with a Pd0 centre, allowing for surmountable barriers (highest ΔG≠ of 22.9 kcal mol−1 for alcoholysis). This proton‐shuffle between methanol and coordinated propyne accounts for experimental requirements (high acid concentration) and reproduces observed regioselectivities as a function of ligand structure. A simple ligand modification is proposed, which is predicted to improve catalytic turnover by three orders of magnitude.
Cube‐in‐Cube Hollow Cu9S5 Nanostructures with Enhanced Photocatalytic Activities in Solar H2 Evolution
Authors: Xu Miao , Wang Min , Ye Tiannan , Liang Na , Jin Lun , Zai Jiantao , Qian Xuefeng 
Published: September 2014

AbstractInvited for the cover of this issue is the group of Xuefeng Qian at Shanghai Jiao Tong University. The image depicts hydrogen being produced from water by solar energy. Read the full text of the article at 10.1002/chem.201403683.
Comparison of methods for estimation of the covariance matrix of measurement errors
Authors: Feital Thiago , Prata Diego Martinez , Pinto José Carlos 
Published: September 2014

AbstractMeasurement errors normally present in measured process variables can mask the actual process conditions and lead to wrong operational decisions. This is due not only to the imprecise measured values but also to the propagation of the measurement error through process models used to perform control and optimization tasks. One possible alternative to deal with this problem is to characterize the measurement errors online and to incorporate the obtained information in the process operation. The present work analyzes the performances of different methods used for characterization of measurement errors in different scenarios commonly found in the industrial practice. Based on the obtained results, a method is proposed for direct evaluation of measurement errors at plant site.
Identification of Green Tea Catechins as Potent Inhibitors of the Polo‐Box Domain of Polo‐Like kinase 1
Authors: Shan Hong‐Mei , Shi Yanxia , Quan Junmin 
Published: September 2014

AbstractPolo‐like kinase 1 (PLK1) plays crucial functions in multiple stages of mitosis and is considered to be a potential drug target for cancer therapy. The functions of PLK1 are mediated by its N‐terminal kinase domain and C‐terminal polo‐box domain (PBD). Most inhibitors targeting the kinase domain of PLK1 have a selectivity issue because of a high degree of structural conservation within kinase domains of all protein kinases. Here, we combined virtual and experimental screenings to identify green tea catechins as potent inhibitors of the PLK1 PBD. Initially, (−)‐epigallocatechin, one of the main components of green tea polyphenols, was found to significantly block the binding of fluorescein‐labeled phosphopeptide to the PBD at a concentration of 10 μm. Next, additional catechins were evaluated for their dose‐dependent inhibition of the PBD and preliminary structure–activity relationships were derived. Cellular analysis further showed that catechins interfere with the proper subcellular localization of PLK1, lead to cell‐cycle arrest in the S and G2M phases, and induce growth inhibition of several human cancer cell types, such as breast adenocarcinoma (MCF7), lung adenocarcinoma (A549), and cervical adenocarcinoma (HeLa). Our data provides new insight into understanding the anticancer activities of green tea catechins.
Childhood Maltreatment, Shame‐Proneness and Self‐Criticism in Social Anxiety Disorder: A Sequential Mediational Model
Authors: Shahar Ben , Doron Guy , Szepsenwol Ohad 
Published: September 2014

Previous research has shown a robust link between emotional abuse and neglect with social anxiety symptoms. However, the mechanisms through which these links operate are less clear. We hypothesized a model in which early experiences of abuse and neglect create aversive shame states, internalized into a stable shame‐based cognitive–affective schema. Self‐criticism is conceptualized as a safety strategy designed to conceal flaws and prevent further experiences of shame. However, self‐criticism maintains negative self‐perceptions and insecurity in social situations. To provide preliminary, cross‐sectional support for this model, a nonclinical community sample of 219 adults from Israel (110 females, mean age = 38.7) completed measures of childhood trauma, shame‐proneness, self‐criticism and social anxiety symptoms. A sequential mediational model showed that emotional abuse, but not emotional neglect, predicted shame‐proneness, which in turn predicted self‐criticism, which in turn predicted social anxiety symptoms. These results provide initial evidence supporting the role of shame and self‐criticism in the development and maintenance of social anxiety disorder. The clinical implications of these findings are discussed Copyright © 2014 John Wiley & Sons, Ltd.Key Practitioner MessagePrevious research has shown that histories of emotional abuse and emotional neglect predict social anxiety symptoms, but the mechanisms that underlie these associations are not clear.Using psycho‐evolutionary and emotion‐focused perspectives, the findings of the current study suggest that shame and self‐criticism play an important role in social anxiety and may mediate the link between emotional abuse and symptoms.These findings also suggest that therapeutic interventions specifically targeting shame and self‐criticism should be incorporated into treatments for social anxiety, especially with socially anxious patients with abuse histories.
Novel Pathways to 2,5‐Dimethylfuran via Biomass‐Derived 5‐(Chloromethyl)furfural
Authors: Dutta Saikat , Mascal Mark 
Published: September 2014

Abstract2,5‐Dimethylfuran (DMF) is one of the most actively pursued biomass‐derived chemicals due to the fact that it can serve both as a biofuel and an intermediate for drop‐in terephthalate polymers. DMF can be accessed via catalytic hydrogenation of 5‐(hydroxymethyl)furfural (HMF), but the difficult accessibility of HMF from cellulosic biomass is a major impediment to the commercial development of such a process. Alternatively, 5‐(chloromethyl)furfural (CMF) is freely accessible in high yield directly from raw biomass and is shown here to be efficiently reduced to DMF under mild conditions via simple derivatives (aldimine, acetal).
Early adverse experience increases emotional reactivity in juvenile rhesus macaques: Relation to amygdala volume
Authors: Howell Brittany R. , Grand Alison P. , McCormack Kai M. , Shi Yundi , LaPrarie Jamie L. , Maestripieri Dario , Styner Martin A. , Sanchez Mar M. 
Published: September 2014

ABSTRACTThis study investigated the impact of infant maltreatment on juvenile rhesus monkeys' behavioral reactivity to novel stimuli and its associations with amygdala volume. Behavioral reactivity to novel stimuli of varying threat intensity was measured using Approach/Avoidance (AA) and Human Intruder (HI) tasks. In vivo magnetic resonance imaging (MRI) was used to measure amygdala volume. Interestingly, group behavioral differences were context‐dependent. When exposed to a human intruder, maltreated subjects displayed more anxious behaviors than controls; however, when presented with fear‐evoking objects, maltreated animals exhibited increased aggression and a shorter latency to inspect the objects. Finally, under testing conditions with the lowest levels of threat (neutral novel objects) maltreated animals also showed shorter latencies to inspect objects, and reduced avoidance and increased exploration compared to controls. This suggests alterations in threat assessment and less behavioral inhibition in animals with early adverse experience compared to controls. Some of these behavioral responses were associated with amygdala volume, which was positively correlated with abuse rates received during infancy, particularly reflecting a relationship with exploration, consistent with previous studies. © 2014 Wiley Periodicals, Inc. Dev Psychobiol 56: 1735–1746, 2014.
The prevalence and adverse associations of stigmatization in people with eating disorders
Authors: Griffiths Scott , Mond Jonathan M. , Murray Stuart B. , Touyz Stephen 
Published: September 2014

ABSTRACTObjectiveTo date, studies of stigma relating to eating disorders have been largely confined to surveys of the public. We sought to examine the prevalence and correlates of stigma as reported by individuals with eating disorders.MethodAn online survey designed to assess frequency of exposure to potentially stigmatizing attitudes and beliefs as well as the perceived impact of this on health and well‐being was completed by a cross‐national sample of 317 individuals with anorexia nervosa (n = 165), bulimia nervosa (n = 66), or Eating Disorder Not Otherwise Specified (EDNOS; n = 86).ResultsParticipants rated two beliefs as both particularly common and particularly damaging, namely “I should be able to just pull myself together” and “I am personally responsible for my condition”. Participants with bulimia nervosa more commonly experienced the belief that they had “no self‐control” and male participants more commonly experienced the belief that they were “less of a man”. More frequent stigmatization was associated with higher levels of eating disorder psychopathology, a longer duration of disorder, lower self‐esteem, and more self‐stigma of seeking psychological help.DiscussionStigma towards individuals with eating disorders, as experienced by sufferers, is common and associated with numerous adverse outcomes. The perceptions that eating disorders are trivial and self‐inflicted should be a focus of destigmatization interventions. Efforts to reduce stigma towards individuals with bulimia nervosa may need to focus on perceptions of self‐control, whereas efforts to reduce stigma towards males with eating disorders may need to focus on perceptions of masculinity/manhood. © 2014 Wiley Periodicals, Inc. (Int J Eat Disord 2015; 48:767–774)
Individual phenotypic variation reduces interaction strengths in a consumer–resource system
Authors: Gibert Jean P. , Brassil Chad E. 
Published: September 2014

SummaryNatural populations often show variation in traits that can affect the strength of interspecific interactions. Interaction strengths in turn influence the fate of pairwise interacting populations and the stability of food webs. Understanding the mechanisms relating individual phenotypic variation to interaction strengths is thus central to assess how trait variation affects population and community dynamics. We incorporated nonheritable variation in attack rates and handling times into a classical consumer–resource model to investigate how variation may alter interaction strengths, population dynamics, species persistence, and invasiveness. We found that individual variation influences species persistence through its effect on interaction strengths. In many scenarios, interaction strengths decrease with variation, which in turn affects species coexistence and stability. Because environmental change alters the direction and strength of selection acting upon phenotypic traits, our results have implications for species coexistence in a context of habitat fragmentation, climate change, and the arrival of exotic species to native ecosystems.
Facile Synthesis of 9,10,19,20‐Tetraarylporphycenes
Authors: Ganapathi Emandi , Chatterjee Tamal , Ravikanth Mangalampalli 
Published: September 2014

AbstractA simple route was developed for the synthesis of 9,10,19,20‐tetraarylporphycenes by combining both McMurry and oxidative synthetic strategies and using readily available precursors. The desired 5,6‐diaryldipyrroethenes, which were prepared in multigram quantities over two steps, were used to prepare 9,10,19,20‐tetraarylporphycenes under mild acid‐catalyzed conditions. As 5,6‐diaryldipyrroethene precursors can easily be prepared in multigram quantities, this method is useful for the preparation of meso‐tetrarylporphycenes that contain different aryl substituents. The molecular structures of these macrocycles were determined by HRMS analysis as well as 1D and 2D NMR studies. The tetraarylporphycenes exhibited a strong Soret band at approximately 380 nm and three Q bands in the region of 580–655 nm. The tetraarylprophycenes are reasonably fluorescent and stable under redox conditions.
Palladium‐Catalyzed Oxidative Synthesis of Aromatic Ketones Using Olefins as Acyl Equivalents through Selective ortho Aromatic C–H Bond Activation
Authors: Khemnar Ashok B. , Bhanage Bhalchandra M. 
Published: September 2014

AbstractAn efficient catalytic system has been developed for selective ortho‐acylation of arenes by oxidative C–H bond activation using a palladium catalyst. Olefins were oxidized to the corresponding aldehydes/benzoyl radicals, which, on coupling with 2‐phenylpyridine, gave the corresponding acylated products in good to excellent yields. 1‐Phenylpyrazole also reacts with substituted olefins to give the acylation products in good yields.
Anti‐inflammatory effects of a casein hydrolysate and its peptide‐enriched fractions on TNFα‐challenged Caco‐2 cells and LPS‐challenged porcine colonic explants
Authors: Mukhopadhya Anindya , Noronha Nessa , Bahar Bojlul , Ryan Marion T. , Murray Brian A. , Kelly Phil M. , O'Loughlin Ian B. , O'Doherty John V. , Sweeney Torres 
Published: September 2014

AbstractBioactive milk peptides are reported to illicit a range of physiological benefits and have been proposed as potential functional food ingredients. The objective of this study was to characterize the anti‐inflammatory properties of sodium caseinate (NaCAS), its enzyme hydrolysate (EH) and peptide‐enriched fractions (5 kDa retentate [R], 1 kDaR and 1 kDa permeate [P]), both in vitro using a Caco‐2 cell line, and also ex vivo using a porcine colonic tissue explant system. Caco‐2 cells were stimulated with tumour necrosis factor alpha (TNFα) and co‐treated with casein hydrolysates for 24 h. Following this, interleukin (IL)‐8 concentrations in the supernatant were measured using enzyme‐linked immunosorbent assay. Porcine colonic tissue was stimulated with lipopolysaccharide and co‐treated with casein hydrolysates for 3 h. The expression of a panel of inflammatory cytokines was measured using qPCR. While dexamethasone reduced the IL‐8 concentration by 41.6%, the 1 kDaR and 1 kDaP fractions reduced IL‐8 by 68.7% and 66.1%, respectively, relative to TNFα‐stimulated Caco‐2 cells (P < 0.05). In the ex vivo system, only the 1 kDaR fraction elicited a decrease in IL1‐α, IL1‐β, IL‐8, TGF‐β and IL‐10 expression (P < 0.05). This study provides evidence that the bioactive peptides present in the 1 kDaR fraction of the NaCAS hydrolysate possess anti‐inflammatory properties in vitro and ex vivo. Further in vivo analysis of the anti‐inflammatory properties of the 1 kDaR is proposed.
Numerical modeling of saturated soils, based on Smoothed Particle Hydrodynamics (SPH)
Authors: Grabe Jürgen , Stefanova Bozhana 
Published: September 2014

AbstractSmoothed particle hydrodynamics (SPH) is a mesh‐free numerical method originally developed in the 1970s for astrophysical analysis. In the recent decades, it has been applied to a wide range of research fields, including fluid and solid mechanics, hydrodynamics and coastal and geotechnical engineering. This paper presents an application of SPH to the problem of interaction between the soil skeleton and the pore water in saturated soils. The formulation of the equations of conservation in SPH has been modified so that a drag force due to seepage is introduced and calculated using Darcy's law. Two test cases are considered for the analysis: a basic drainage of a vertical sand column due to gravity and seepage through a vertical dam (also known as the Muskat problem). Both simulations show very good agreement with the analytical solutions. The results prove the potential of SPH.Numerische Modellierung gesättigter Böden mit der Smoothed Particle Hydrodynamics – Teil 1: Grundwasserströmungsanalyse. Die Smoothed Particle Hydrodynamics (SPH) ist eine netzfreie numerische Methode, die ursprünglich in den 1970er‐Jahren für astrophysikalische Berechnungen entwickelt wurde. In den vergangenen Jahrzehnten hat sie zahlreiche Anwendungsgebiete gefunden, u. a. Fluid‐ und Strukturmechanik, Hydrodynamik, Küsteningenieurwesen und auch Geotechnik. Dieser Artikel zeigt eine Anwendung der SPH zur Untersuchung der Interaktion zwischen Korngerüst und Porenwasser wassergesättigter Böden. Zu diesem Zweck wurde die Formulierung der Erhaltungsgleichungen um eine Strömungskraft basierend auf dem Gesetz von Darcy erweitert. Zur Validierung werden zwei Sickerströmungsprobleme betrachtet: die Entwässerung einer Bodensäule unter Gravitation und die Strömung durch einen vertikalen Damm, auch bekannt als das Muskat‐Problem. Beide Simulationen haben eine sehr gute Übereinstimmung mit den analytischen Lösungen gezeigt. Die Ergebnisse bestätigen das Potential der SPH.
Kritische Anmerkungen zu DIN 18321 – ATV Düsenstrahlarbeiten
Authors: Schulze Bertram , Jud Holger 
Published: September 2014

AbstractDie Allgemeinen Technischen Vertragsbedingungen für Bauleistungen, die Bestandteil der VOB Teil C sind, sollen die Zusammenarbeit von Auftraggeber und Auftragnehmer regeln und erleichtern. Insbesondere im Falle von Unstimmigkeiten bei Abrechnungsfragen sollen die ATV Hilfestellungen für gerichtliche und außergerichtliche Einigungen liefern. Sie sollen somit dem Rechtsfrieden dienen. Nach Auffassung der Verfasser ist dies mit den ATV Düsenstrahlarbeiten, DIN 18321, aber nicht der Fall. In einer angeregten Überarbeitung sollte dem verfahrensbedingt engen Zusammenwirken von Boden‐ und Baustoff/Verfahren durch eine klare Zuweisung von Auftraggeber‐ und Auftragnehmeraufgaben und durch eine gemeinsam zu verantwortende Qualitätssicherung stärker Rechnung getragen werden als bisher. Der zuständige Normenausschuss hat eine detaillierte Zusammenstellung der Verbesserungsvorschläge erhalten.Critical notes on DIN 18321 – ATV Jet Grouting Works. The purpose of the General Technical Terms of Contract for Building Works (ATV), which are included in part C of the Contract Rules for Award of Public Works Contracts (VOB), is to regulate and facilitate the cooperation between client and contractor. Especially in the case of discrepancies on billing issues, the ATV is meant to provide support for arrangements both in and out of court. The general purpose is to give legal certainty. In the authors' view, the ATV Jet Grouting Works, DIN 18321:2012‐09, do not achieve this purpose. In a suggested revision, the close interaction of soil and building material/treatment needs to be taken more into account, by a clearly defined allocation of client and contractor tasks as well as by a shared responsibility with respect to quality assurance. The responsible standards committee has been sent a detailed compilation of the suggestions for improvement.
Experimental Study on the Permeability and Thermal Resistance of the Cement Clinker Accumulation
Authors: Wen Yan , Wang Jia‐shun , Yue Hai‐long , Jing Tong , Liu Bin 
Published: September 2014

A device was designed for measuring the permeability of cement clinker accumulation in three dimensions. In addition, the equivalent permeability and equivalent thermal resistance coefficient were introduced to evaluate the penetration ability in high temperature. First, the equivalent permeability of the accumulation in three dimensions was measured at a room temperature of 298 K and the order of magnitude was decided to be 10−6. The difference degree of equivalent permeability was less than 15% in each direction; Then the rule of equivalent permeability in three‐dimensional changed with temperature was obtained by the air‐cooled experiments of the cement clinker accumulation at an initial temperature – 773 K; Finally, the law of equivalent thermal resistance coefficient was obtained through comparing the change of the permeability from high temperature to room temperature. The results showed that the equivalent thermal resistance coefficient change with temperature was nonlinear and the equivalent thermal resistance coefficient changed from 1.0 to 1.3 when the temperature was in the range of 298 K to 773 K.