bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Synthesis and Biological Screening of 1,2,4‐Triazole Derivatives.
Authors: Godhani Dinesh R. , Jogel Anand A. , Sanghani Anil M. , Mehta Jignasu P.
Published: October 2015

Title compounds (VI) exhibit moderate to good antibacterial and antitubercular activity.
ChemInform Abstract: Organocatalytic Asymmetric 1,6‐Addition/1,4‐Addition Sequence to 2,4‐Dienals for the Synthesis of Chiral Chromans.
Authors: Poulsen Pernille H. , Feu Karla Santos , Paz Bruno Matos , Jensen Frank , Joergensen Karl Anker
Published: October 2015

A wide range of optically active chromans are highly regio‐ and stereoselectively obtained utilizing a novel asymmetric 1,6‐Friedel—Crafts/1,4‐oxa‐Michael cascade reaction of hydroxyarenes with 2,4‐dienals.
ChemInform Abstract: Base‐Promoted β‐C(sp3)—H Functionalization of Enaminones: An Approach to Polysubstituted Pyridines.
Authors: Shen Jinhai , Cai Dingding , Kuai Changsheng , Liu Yunqi , Wei Ming'e , Cheng Guolin , Cui Xiuling
Published: October 2015

1‐Arylethylamines and 1,3‐diarylprop‐2‐ynones give 2,4,6‐triarylpyridines regioselectively under basic conditions using air as the oxidant.
ChemInform Abstract: Three‐Component Functionalized Dihydropyridine Synthesis via a Formal Inverse Electron‐Demand Hetero‐Diels—Alder Reaction.
Authors: Yan Xiaonan , Ling Fei , Zhang Yuchen , Ma Cheng
Published: October 2015

The reaction proceeds trough a formal inverse electron‐demand hetero‐Diels—Alder reaction of electron‐deficient 1‐azadienes with metalated ynamide intermediates arising from a Cu‐catalyzed azide—alkyne reaction.
ChemInform Abstract: Lewis Acid Catalyzed Condensation—Cyclization Cascade: Direct Synthesis of Di/Trifluoromethyl‐1,2,3,4‐tetrahydroquinazolines.
Authors: Prakash G. K. Surya , Papp Attila , Munoz Socrates B. , May Nathan , Jones John‐Paul , Haiges Ralf , Esteves Pierre Mothe , Mathew Thomas
Published: October 2015

Fluorinated quinazolines are conveniently obtained from simple difluoro/trifluoroacetaldehyde hemiacetals and aromatic amines using gallium triflate as safe and stable Lewis acid catalyst.
ChemInform Abstract: N‐Protected 1,2‐Oxazetidines as a Source of Electrophilic Oxygen: Straightforward Access to Benzomorpholines and Related Heterocycles by Using a Reactive Tether.
Authors: Javorskis Tomas , Sriubaite Simona , Bagdziunas Gintautas , Orentas Edvinas
Published: October 2015

1,2‐Oxazetidine reacts with organometallic compounds to provide electrophilic oxygen with a nitrogen‐terminated two‐carbon‐atom tether.
ChemInform Abstract: Cyclization of Allenamides to Benzazepine Skeleton Through Pd Catalysis.
Authors: Kim Hongtaek , Kim Guncheol
Published: October 2015

This is the first report for the synthesis of seven‐membered azepine ring compounds (III) from allenamides.
ChemInform Abstract: Structure Determination from Powder Diffraction Data: Past, Present and Future Challenges
Authors: Meden Anton , Radosavljevic Evans Ivana
Published: October 2015

Review: 93 refs.
ChemInform Abstract: Freestanding Ultrathin Metallic Nanosheets: Materials, Synthesis, and Applications
Authors: Ling Tao , Wang Jing‐Jing , Zhang Hao , Song Shu‐Tao , Zhou Yu‐Zhu , Zhao Jiong , Du Xi‐Wen
Published: October 2015

Review: 36 refs.
ChemInform Abstract: Titanate and Titania Nanostructured Materials for Environmental and Energy Applications: A Review
Authors: Zhang Yanyan , Jiang Zhelong , Huang Jianying , Lim Linda Y. , Li Wenlong , Deng Jiyang , Gong Dangguo , Tang Yuxin , Lai Yuekun , Chen Zhong
Published: October 2015

Review: 306 refs.
ChemInform Abstract: The Ligand Polyhedral Model Approach to the Mechanism of Complete Carbonyl Exchange in [Rh4(CO)12] and [Rh6(CO)16]
Authors: Johnson Brian F. G.
Published: October 2015

Review: 30 refs.
ChemInform Abstract: Organocatalytic Reactions Enabled by N‐Heterocyclic Carbenes
Authors: Flanigan Darrin M. , Romanov‐Michailidis Fedor , White Nicholas A. , Rovis Tomislav
Published: October 2015

Review: 374 refs.
ChemInform Abstract: Gold(I)‐Catalyzed Activation of Alkynes for the Construction of Molecular Complexity
Authors: Dorel Ruth , Echavarren Antonio M.
Published: October 2015

Review: 812 refs.
ChemInform Abstract: Transition‐Metal‐Catalyzed Site‐Selective C—H Functionalization of Quinolines Beyond C2 Selectivity
Authors: Iwai Tomohiro , Sawamura Masaya
Published: October 2015

Review: 81 refs.
ChemInform Abstract: Recent Advancements in Chiral Porphyrin Self‐Assembly
Authors: Monti Donato
Published: October 2015

Review: 163 refs.
ChemInform Abstract: Recent Progress in the Use of Pd‐Catalyzed C—C Cross‐Coupling Reactions in the Synthesis of Pharmaceutical Compounds
Authors: Biajoli Andre F. P. , Schwalm Cristiane S. , Limberger Jones , Claudino Thiago S. , Monteiro Adriano L.
Published: October 2015

Review: 77 refs.
ChemInform Abstract: Recent Advances in Reductive Amination Catalysis and Its Applications
Authors: Alinezhad Heshmatollah , Yavari Hossein , Salehian Fatemeh
Published: October 2015

Review: 111 refs.
ChemInform Abstract: Recent Developments in Enantioselective Nickel(II)‐Catalyzed Conjugate Additions
Authors: Pellissier Helene
Published: October 2015

Review: [96 refs.
ChemInform Abstract: Recent Progress Toward the Introduction of Functionalized Difluoromethylated Building Blocks onto C(sp2) and C(sp) Centers
Authors: Belhomme Marie‐Charlotte , Besset Tatiana , Poisson Thomas , Pannecoucke Xavier
Published: October 2015

Review: [86 refs.
ChemInform Abstract: Direct Arylation and Heterogeneous Catalysis; Ever the Twain Shall Meet
Authors: Cano Rafael , Schmidt Alexander F. , McGlacken Gerard P.
Published: October 2015

Review: 67 refs.
ChemInform Abstract: Metalorganocatalysis: Cooperating Transition‐Metal Catalysis and Organocatalysis Through a Covalent Bond
Authors: Dong Xiu‐Qin , Zhao Qingyang , Li Pan , Chen Caiyou , Zhang Xumu
Published: October 2015

Review: [31 refs.
ChemInform Abstract: Recent Progress Towards Ionic Hydrogenation: Lewis Acid Catalyzed Hydrogenation Using Organosilanes as Donors of Hydride Ions
Authors: Liu Tianqi , Wang Xiaojian , Yin Dali
Published: October 2015

Review: 50 refs.
ChemInform Abstract: Aggregation‐Induced Emission of Siloles
Authors: Zhao Zujin , He Bairong , Tang Ben Zhong
Published: October 2015

Review: [56 refs.
ChemInform Abstract: Discovering Functional, Non‐proteinogenic Amino Acid Containing, Peptides Using Genetic Code Reprogramming
Authors: Rogers J. M. , Suga H.
Published: October 2015

Review: [71 refs.
Lernen über digitale Medien in der Chemielehrerausbildung
Authors: Krause Moritz , Eilks Ingo
Published: October 2015

Dieser Artikel beschreibt die systematische Weiterentwicklung einer Lehrveranstaltung zur Nutzung digitaler Medien im Chemieunterricht an der Universität Bremen. Nach dem Ansatz der Partizipativen Aktionsforschung für Innovationen in der Hochschullehre wurden die Lehrveranstaltung über drei Jahre zyklisch verändert und begleitend dazu ausgewählte Aspekte des Einflusses einer solchen Lehrveranstaltung auf die Lernenden untersucht. Fokus der Untersuchung war der Effekt der Lehrveranstaltung auf die Einstellungen und die Selbstwirksamkeitserwartung der Studierenden zu digitalen Medien im Allgemeinen und bezogen auf den Chemieunterricht. Die Struktur der Lehrveranstaltung wird vorgestellt, Erfahrungen und Ergebnisse werden diskutiert.
Rationale, Design, and Methodological Aspects of the BUDAPEST‐GLOBAL Study (Burden of Atherosclerotic Plaques Study in Twins—Genetic Loci and the Burden of Atherosclerotic Lesions)
Authors: Maurovich‐Horvat Pál , Tárnoki Dávid L. , Tárnoki Ádám D. , Horváth Tamás , Jermendy Ádám L. , Kolossváry Márton , Szilveszter Bálint , Voros Viktor , Kovács Attila , Molnár Andrea Á. , Littvay Levente , Lamb Hildo J. , Voros Szilard , Jermendy György , Merkely Béla
Published: October 2015

The heritability of coronary atherosclerotic plaque burden, coronary geometry, and phenotypes associated with increased cardiometabolic risk are largely unknown. The primary aim of the Burden of Atherosclerotic Plaques Study in Twins—Genetic Loci and the Burden of Atherosclerotic Lesions (BUDAPEST‐GLOBAL) study is to evaluate the influence of genetic and environmental factors on the burden of coronary artery disease. By design this is a prospective, single‐center, classical twin study. In total, 202 twins (61 monozygotic pairs, 40 dizygotic same‐sex pairs) were enrolled from the Hungarian Twin Registry database. All twins underwent non–contrast‐enhanced computed tomography (CT) for the detection and quantification of coronary artery calcium and for the measurement of epicardial fat volumes. In addition, a single non–contrast‐enhanced image slice was acquired at the level of L3‐L4 to assess abdominal fat distribution. Coronary CT angiography was used for the detection and quantification of plaque, stenosis, and overall coronary artery disease burden. For the primary analysis, we will assess the presence and volume of atherosclerotic plaques. Furthermore, the 3‐dimensional coronary geometry will be assessed based on the coronary CT angiography datasets. Additional phenotypic analyses will include per‐patient epicardial and abdominal fat quantity measurements. Measurements obtained from monozygotic and dizygotic twin pairs will be compared to evaluate the genetic or environmental effects of the given phenotype. The BUDAPEST‐GLOBAL study provides a unique framework to shed some light on the genetic and environmental influences of cardiometabolic disorders.
Identification, modeling, and characterization studies ofTetrahymena thermophilamyosinFERMdomains suggests a conserved core fold but functional differences
Authors: Martin Che L. , Singh Shaneen M.
Published: October 2015

Myosins (MYO) define a superfamily of motor proteins which facilitate movement along cytoskeletal actin filaments in an ATP‐dependent manner. To date, over 30 classes of myosin have been defined that vary in their roles and distribution across different taxa. The multidomain tail of myosin is responsible for the observed functional differences in different myosin classes facilitating differential binding to different cargos. One domain found in this region, the FERM domain, is found in several diverse proteins and is involved in many biological functions ranging from cell adhesion and actin‐driven cytoskeleton assembly to cell signaling. Recently, new classes of unconventional myosin have been identified inTetrahymena thermophila. In this study, we have identified, modeled, and characterized eight FERM domains from the unconventionalT. thermophilamyosins as their complete functional MyTH4‐FERM cassettes. Our results reveal notable sequence, structural, and electrostatic differences betweenT. thermophilaand other characterized FERM domains. Specifically,T. thermophilaFERM domains contain helical inserts or extensions, which contribute to significant differences in surface electrostatic profiles ofT. thermophilamyosin FERMs when compared to the conventional FERM domains. Analyses of the modeled domains reveal differences in key functional residues as well as phosphoinositide‐binding signatures and affinities. The work presented here broadens the scope of our understanding of myosin classes and their inherent functions, and provides a platform for experimentalists to design rational experimental studies to test the functional roles forT. thermophilamyosins. © 2015 Wiley Periodicals, Inc.
Clinicopathological and genetic differences between low‐grade and high‐grade colorectal mucinous adenocarcinomas
Authors: Yoshioka Yasumasa , Togashi Yosuke , Chikugo Takaaki , Kogita Akihiro , Taguri Masataka , Terashima Masato , Mizukami Takuro , Hayashi Hidetoshi , Sakai Kazuko , de Velasco Marco A. , Tomida Shuta , Fujita Yoshihiko , Tokoro Tadao , Ito Akihiko , Okuno Kiyotaka , Nishio Kazuto
Published: October 2015

BACKGROUND

Although colorectal mucinous adenocarcinomas (MCs) are conventionally regarded as exhibiting high‐grade differentiation, they can be divided by differentiation into 2 groups according to the glandular appearance: low‐grade mucinous adenocarcinoma (low‐MC) and high‐grade mucinous adenocarcinoma (high‐MC).

METHODS

Patients with colorectal cancer (CRC) who underwent surgical resection between 2000 and 2012 were enrolled in this study. Among the cases with MC, the clinicopathological and genetic differences between low‐MC and high‐MC were investigated with next‐generation sequencing.

RESULTS

A total of 1373 patients with CRC were analyzed. Forty patients (2.9%) had MC, and 13 patients had high‐MC. Patients with MC had significantly shorter disease‐free survival (DFS) and overall survival (OS) periods than those with nonmucinous carcinoma. When low‐MC patients and high‐MC patients were compared, those with high‐MC had significantly shorter DFS and OS periods than those with low‐MC. Multivariate analyses revealed that high‐MC was significantly associated with both shorter DFS and shorter OS, but low‐MC was not. A genome analysis revealed that low‐MC had a considerably larger number of mutations than high‐MC, and Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations and adenomatous polyposis coli mutations were particularly frequently found in low‐MC. In contrast, SMAD family member 4 (SMAD4) mutations were frequently found in high‐MC.

CONCLUSIONS

High‐MC is an independent prognostic factor in CRC (but low‐MC is not), and it is genetically different from other CRCs, including low‐MC. Both the clinicopathological differences and the genetic differences suggest that low‐MC and high‐MC should be distinguished in clinical settings. Cancer 2015;121:4359–68. © 2015 American Cancer Society.
Differentiation between Shallow and Deep Charge Trap States on Single Poly(3‐hexylthiophene) Chains through Fluorescence Photon Statistics
Authors: Grußmayer Kristin S. , Steiner Florian , Lupton John M. , Herten Dirk‐Peter , Vogelsang Jan
Published: October 2015

Blinking of the photoluminescence (PL) emitted from individual conjugated polymer chains is one of the central observations made by single‐molecule spectroscopy (SMS). Important information, for example regarding excitation energy transfer, can be extracted by evaluating dynamic quenching. However, the nature of trap states, which are responsible for PL quenching, often remains obscured. We present a detailed investigation of the photon statistics of single poly(3‐hexylthiophene) (P3HT) chains obtained by SMS. The photon statistics provide a measure of the number and brightness of independently emitting areas on a single chain. These observables can be followed during blinking. A decrease in PL intensity is shown to be correlated with either 1) a decrease in the average brightness of the emitting sites; or 2) a decrease in the number of emitting regions. We attribute these phenomena to the formation of 1) shallow charge traps, which can weakly affect all emitting areas of a single chain at once; and 2) deep traps, which have a strong effect on small regions within the single chains.
Efficient Epimerization of Aldoses Using Layered Niobium Molybdates
Authors: Takagaki Atsushi , Furusato Shogo , Kikuchi Ryuji , Oyama S. Ted
Published: October 2015

Both non‐acidic LiNbMoO6 and strongly acidic HNbMoO6 efficiently catalyze the epimerization of sugars including glucose, mannose, xylose, and arabinose in water. The reactions over these oxides reached almost equilibrium within a few hours where yields of corresponding epimers from glucose, xylose, and arabinose were 24–29 %. The layered mixed oxides functioned as heterogeneous catalysts and could be reused without loss of activity, whereas bulk molybdenum oxide MoO3 was completely dissolved during the reaction. A 13C substitution experiment showed that the reaction proceeds through a 1,2‐rearrangement mechanism. The surface Mo octahedra were responsible for the activity. The layered HNbMoO6 could also afford mannose from cellobiose through hydrolysis and successive epimerization.
Assessing biodiversity and endemism using phylogenetic methods across multiple taxonomic groups
Authors: González‐Orozco Carlos E. , Mishler Brent D. , Miller Joseph T. , Laffan Shawn W. , Knerr Nunzio , Unmack Peter , Georges Arthur , Thornhill Andrew H. , Rosauer Dan F. , Gruber Bernd
Published: October 2015

Identifying geographical areas with the greatest representation of the tree of life is an important goal for the management and conservation of biodiversity. While there are methods available for using a single phylogenetic tree to assess spatial patterns of biodiversity, there has been limited exploration of how separate phylogenies from multiple taxonomic groups can be used jointly to map diversity and endemism. Here, we demonstrate how to apply different phylogenetic approaches to assess biodiversity across multiple taxonomic groups. We map spatial patterns of phylogenetic diversity/endemism to identify concordant areas with the greatest representation of biodiversity across multiple taxa and demonstrate the approach by applying it to the Murray–Darling basin region of southeastern Australia. The areas with significant centers of phylogenetic diversity and endemism were distributed differently for the five taxonomic groups studied (plant genera, fish, tree frogs, acacias, and eucalypts); no strong shared patterns across all five groups emerged. However, congruence was apparent between some groups in some parts of the basin. The northern region of the basin emerges from the analysis as a priority area for future conservation initiatives focused on eucalypts and tree frogs. The southern region is particularly important for conservation of the evolutionary heritage of plants and fishes.
Out of Africa: evidence of the obligate mutualism between long corolla tubed plant and long‐tongued fly in the Himalayas
Authors: Paudel Babu Ram , Shrestha Mani , Dyer Adrian G. , Zhu Xing‐Fu , Abdusalam Aysajan , Li Qing‐Jun
Published: October 2015

Mutualism between long corolla tubed plants and their potential pollinators, long‐tongued flies, is a classic example of coevolution, but to date, has only been reported from the regions of southern Africa. Many plant species from the Himalayas also show botanical characteristics that could be consistent with pollination by long‐tongued flies. Here, we seek the evidence of the “long‐tongued‐long tubed fly/flower” mutualism out of Africa, in a different continent and climatic region, the Himalayas.

Floral traits of Himalayan region endemic alpine genus, Roscoea, indicate possible mutualism with long‐tongued flies for pollination success; however, effective pollinators of this genus are yet unknown. This study investigates whether long‐tongued flies and Roscoea purpurea in Nepal Himalayas show exclusive mutualism for their survival/reproduction.

We made extensive observations of floral visitors of R. purpurea and food source of Philoliche longirostris across their wide ranges of populations in Nepal Himalayas for three consecutive years (2012–2014). To confirm the obligate reliance of R. purpurea upon P. longirostris for pollination success, manipulated pollination experiments were conducted at two populations for 2 years. Similarly foraging behavior, visitation frequency, and pollination efficiency of P. longirostris were assessed at two populations for 2 years, and its contribution for the reproductive success of R. purpurea was evaluated. Our results indicate that R. purpurea is self‐compatible but lacks autonomous selfing and obligatorily relies on P. longirostris for reproductive success. Across all populations, P. longirostris was observed as an exclusive and highly efficient pollinator of R. purpurea, while P. longirostris exclusively depends up on R. purpurea for food source.

Out of Africa, this study provides the first evidence of long‐tongued fly pollination system and indicates the possibility of additional instances of such a rare phenomenon in the Himalayas. Finding of specialized pollinator of Roscoea only at its evolutionary center indicates that Roscoea species are originally pollinated by long‐tongued flies. Spatial mismatch with specialized pollinators may have induced the evolution of autonomous selfing in North Indochinese clades of Roscoea. This finding thus substantiates how geographic disjunction causes the shifting of pollination mechanism in closely related plant species.
High‐resolution analysis of the murine MHC class II immunopeptidome
Authors: Sofron Adriana , Ritz Danilo , Neri Dario , Fugmann Tim
Published: October 2015

The reliable identification of peptides bound to major histocompatibility complex (MHC) class II is fundamental for the study of the host immune response against pathogens and the pathogenesis of autoimmune conditions. Here, we describe an improved methodology combining immuno‐affinity enrichment of MHC class II complexes, optimized elution conditions and quadrupole Orbitrap mass spectrometry‐based characterization of the immunopeptidome. The methodology allowed the identification of over 1000 peptides with 1% false discovery rate from 108 murine A20 lymphoma cells. The study revealed the I‐Ad‐specific motif in high resolution after multisequence alignment. The methodology was generally applied to the purification of MHC class II from cell lines and murine spleens. We identified 2963 peptides from BALB/c and 2712 from C57BL/6 mouse spleens. The identification of peptides bound to MHC class II in vitro and in vivo will facilitate the characterization of T‐cell specificities, as well as the development of biotherapeutics and vaccines.
Formation of Hybrid Guanidine‐Stabilized Bis(μ‐oxo)dicopper Cores in Solution: Electronic and Steric Perturbations
Authors: Herres‐Pawlis Sonja , Haase Roxana , Verma Pratik , Hoffmann Alexander , Kang Peng , Stack T. Daniel P.
Published: October 2015

A series of new hybrid peralkylated amine‐guanidine ligands based on a 1,3‐propanediamine backbone and their Cu‐O2 chemistry is reported. The copper(I) complexes react readily with O2 at low temperatures in aprotic solvents with weakly coordinating anions to form exclusively bis(μ‐oxo)dicopper species (O). Variation of the substituents on each side of the hybrid bidentate ligand reveal that less sterically demanding amine and guanidine substituents increase not only the thermal stability of the formed O cores but also enhance inner‐sphere phenolate hydroxylation pathways. TD‐DFT analysis on selected guanidine‐amine O species suggest that the additional visible‐wavelength feature observed is a guanidine π* → Cu2O2 LMCT, which appears along with the classic oxo‐σu* → CuIII and πσ* → CuIII LMCT transitions.
Application of oxygen during olive fruit crushing impacts on the characteristics and sensory profile of the virgin olive oil
Authors: Sánchez‐Ortiz Araceli , Bejaoui Mohamed Aymen , Herrera María Paz Aguilera , Jiménez Márquez Antonio , Beltrán Maza Gabriel
Published: October 2015

A novel crushing process which involves increasing the level of oxygen during the virgin olive oil (VOO) extraction has been applied to develop new knowledge on the biosynthesis of the compounds responsible for sensory, nutritional, and technological quality of VOO. The singular composition of VOO is the result of a series of physical, chemical, and biochemical processes that occur during its extraction procedure. The extraction conditions, temperature, time, addition of water, and oxygen availability, can modulate the final composition of VOO. The last parameter, oxygen, is a known co‐factor for the many endogenous enzyme activities present in the olive fruit, mainly oxide‐reductases. The present study focuses on the influence of oxygen during the crushing of olive fruits on enzyme activities and the process yield. Three different cultivars, namely “Picual,” “Arbequina,” and “Blanqueta”, were selected for the study. The increase of oxygen concentration during crushing produces a significant change in the volatile composition and sensory profile; however, no significant differences were shown on the content of fatty acid composition, total phenols, pigments, tocopherols, and qualitative parameters. This could be a useful analysis tool while designing new prototypes of mills or while working with breeding selection programs.

Practical applications: The application of oxygen during olive fruit crushing in the oil extraction process has been studied. The information provided by this study enables to increase the knowledge on metabolism pathway in olive fruit while working with breeding selection programs. The present study can be useful to clarify the optimum time, crushing, or malaxation to apply atmospheric control to the VOO extraction. Moreover, the results obtained in this work suggest new research opportunities in order to design new prototypes of mills that allow the modification of the sensory characteristics VOO.

The increase of oxygen concentration during crushing produces a significant change in the volatile composition and sensory profile; however, no significant differences were shown on the content of fatty acid composition, total phenols, pigments, tocopherols, and qualitative parameters. Oxygen availability can modulate the final composition of virgin olive oil.
Catalytic Enantioselective Synthesis of Trisubstituted Secondary Allylic Alcohols Starting from Terminal Alkynes and Aldehydes
Authors: Morimoto Haruki , Harada Toshiro
Published: October 2015

A general one‐pot method for the enantioselective synthesis of β,β‐disubstituted allylic alcohols has been developed starting from readily available terminal alkynes and aldehydes. Trisubstituted (E)‐vinylaluminium reagents, generated regio‐ and stereoselectively by the Zr‐catalyzed carboalumination of the alkynes with Me3Al, was used in subsequent enantioselective addition reactions with aldehydes using a DPP‐H8‐BINOL‐derived titanium catalyst system at low catalyst loading (5 mol‐%).
A Stereoselective Synthesis of (+)‐Piscidic Acid and Cimicifugic Acid L
Authors: Miranda Vanessa , Maycock Christopher D. , Ventura M. Rita
Published: October 2015

Alkylation of the lithium enolate of (2S,3S,5S,6S)‐dimethoxy‐2,3‐dimethyl‐1,4‐dioxane‐5,6‐dithiocarboxylate using 4‐benzyloxybenzyl bromide stereoselectively gave two new stereogenic centres with the carboxylate groups in a cis relationship. Hydrolytic deprotection of this intermediate produced the natural product (+)‐piscidic acid. Installation of a cinnamic acid ester at the secondary hydroxy group was followed by selective deprotection to give a mixture of cis/trans cinnamates in a 3:1 ratio. Finally, the natural product cimicifugic acid L was obtained.
Imidazole‐Based Sensitizers Containing Double Anchors for Dye‐Sensitized Solar Cells
Authors: Yen Yung‐Sheng , Ni Jen‐Shyang , Lin Tse‐Yen , Hung Wei‐I , Lin Jiann T. , Yeh Ming‐Chang P.
Published: October 2015

New imidazole‐based organic dyes with two 2‐cyanoacetic acid acceptors/anchors connected at the C‐4 and C‐5 positions, and a carbazole or arylamine donor connected at the C‐2 position of the imidazole entity were synthesized and used as sensitizers for dye‐sensitized solar cells. The dyes exhibit optical absorption from 300–600 nm with high molar extinction coefficients. The inclusion of a hexyl chain at the nitrogen atom of the imidazole was found to result in a large twist of the C‐4 segment from the imidazole and, hence, to less efficient electron injection. Although dye aggregation results in light harvesting at longer wavelength regions, it also leads to excited‐state quenching and hinders electron injection. Consequently, only moderate conversion efficiencies of DSSCs were achieved. Upon addition of CDCA coadsorbents, up to ca. 30 % improvement of the cell efficiency was achieved. The best cell efficiency reached 4.97 % with addition of 50 mM CDCA.
The Quest for Carbenic Nitrile Imines: Experimental and Computational Characterization of C‐Amino Nitrile Imine
Authors: Nunes Cláudio M. , Reva Igor , Rosado Mário T. S. , Fausto Rui
Published: October 2015

C‐Amino nitrile imine has been generated as primary photoproduct (λ = 220 nm) of 5‐amino‐2H‐tetrazole isolated in an argon matrix at 15 K. Subsequent photochemical experiments (λ = 330 nm) demonstrated that C‐amino nitrile imine isomerizes to the corresponding three‐membered‐ring 1H‐diazirine and decomposes to methylenimine. The experimentally observed νas(CNN) absorption at 1998 cm–1 and a carbenic resonance structure contribution of around 20 %, predicted by natural resonance theory calculations, demonstrate that the protoproduced C‐amino nitrile imine has significant carbenic character. These results pave the way to the discovery of carbenic nitrile imines.
Synthesis and (Spectro)electrochemistry of Ferrocenyl‐Substituted Pyridine Derivatives
Authors: Podolan Gabriel , Hettmanczyk Lara , Hommes Paul , Sarkar Biprajit , Reissig Hans‐Ulrich
Published: October 2015

We describe a novel approach to highly functionalized ferrocenyl‐substituted pyridine derivatives. Key reaction is the cyclocondensation of an easily available β‐ketoenamide bearing an N‐ferrocenylcarbonyl group. The resulting 4‐hydroxypyridine derivatives were converted into the corresponding pyrid‐4‐yl nonaflates, which were employed in a range of palladium‐catalyzed coupling reactions. The reaction sequence delivers a library of new 2‐ferrocenyl‐substituted pyridine derivatives, including compounds with two ferrocene moieties, a butadiyne derivative, a 2,4‐bisferrocenylpyridine, and a compound with a thiophene core and two 2‐ferrocenylpyridine groups. The compounds were investigated by UV/Vis spectroscopy and by (spectro)electrochemistry. The (spectro)electrochemical results conclusively prove that the reaction takes place through a ferrocene‐centered oxidation and a reduction based on the heterocyclic part of the molecule. Intriguing effects on the electrochemical responses of these systems upon changing the electrolyte are also observed.
Trimethylsilyloxide‐Catalysed Peterson Olefinations with 2,2‐Bis(trimethylsilyl)‐1,3‐dithiane
Authors: Manvar Atul , O'Shea Donal F.
Published: October 2015

The synthesis of the reagent 2,2‐bis(trimethylsilyl)‐1,3‐dithiane was directly achieved in an excellent yield from 1,3‐dithiane in one step. The bench‐stable reagent can be utilized for Peterson olefinations using either TMSOK/Bu4NCl or fluoride ion as promoter of α‐silyl carbanion formation, thereby generating ketene dithioacetals, which are versatile intermediates in organic synthesis. Olefination reactions were successfully achieved with aromatic, heteroaromatic, aliphatic aldehydes and ketones.
Modulation of pain via expectation of its location
Authors: Stanton T.R. , Gilpin H.R. , Reid E. , Mancini F. , Spence C. , Moseley G.L.
Published: October 2015

Background

The spatial precision of expectancy effects on pain is unclear. We hypothesized that expecting nociceptive stimuli at particular skin sites would have an analgesic effect on nociceptive stimuli presented between them (middle zone).

Methods

Laser stimuli (evoking pin‐prick pain) were delivered to three discrete skin zones on the forearm, under two conditions. During ‘Localization’, participants’ expectation of stimuli was spatially divided between two locations (expected stimuli in only the outer two skin zones): pain intensity and stimulus location were judged. During ‘No‐localization’ (control condition), participants had no expectation concerning stimulus location; only pain intensity was rated. Additional experiments assessed the importance of the actual location on the forearm by: shifting all skin zones proximally towards the elbow (control for joint proximity, Experiment 2); adding a fourth zone distally (control for interaction between joint proximity and enhanced distal inhibition, Experiment 3).

Results

All experiments demonstrated spatially specific pain modulation, but only Experiment 2 (near elbow) supported our hypothesis: middle zone pain intensity was significantly lower (p = 0.02) during Localization than No‐localization. Experiment 1 (near wrist) found reduced pain intensity during Localization only for the distal zone (p = 0.04). Experiment 3 confirmed this effect: reduced pain during Localization occurred only for the most distal zone (p = 0.046).

Conclusion

Expecting a painful stimulus in non‐adjacent skin sites has spatially specific effects on pain modulation, but this reflects an interaction between the expected location of stimulation and the actual location. This suggests a more complex connection between somatotopic maps and nociceptive modulation than previously thought; several distinct mechanisms likely contribute.
Assessing the significance of the correlation between the components of a bivariate Gaussian random field
Authors: Bevilacqua Moreno , Vallejos Ronny , Velandia Daira
Published: October 2015

Assessing the significance of the correlation between the components of a bivariate random field is of great interest in the analysis of spatial data. This problem has been addressed in the literature using suitable hypothesis testing procedures or using coefficients of spatial association between two sequences. In this paper, testing the association between autocorrelated variables is addressed for the components of a bivariate Gaussian random field using the asymptotic distribution of the maximum likelihood estimator of a specific parametric class of bivariate covariance models. Explicit expressions for the Fisher information matrix are given for a separable and a nonseparable version of the parametric class, leading to an asymptotic test. The empirical evidence supports our proposal, and as a result, in most of the cases, the new test performs better than the modifiedttest even when the bivariate covariance model is misspecified or the distribution of the bivariate random field is not Gaussian. Finally, to illustrate how the proposed test works in practice, we study a real dataset concerning the relationship between arsenic and lead from a contaminated area in Utah, USA. Copyright © 2015 John Wiley & Sons, Ltd.
Pomolic Acid Inhibits Invasion of Breast Cancer Cells Through the Suppression of CXC Chemokine Receptor Type 4 Expression
Authors: Kim Buyun , Kim Ji‐Hun , Park Byoungduck
Published: October 2015

High mortality of cancer‐mediated deaths is due to metastasis. CXC chemokine receptor type 4 (CXCR4) signaling has been demonstrated to be involved in migration of breast cancer. Thus, identification of CXCR4 inhibitor has been challenged constantly as an anticancer drug. This study is aimed to investigate the CXCR4 inhibitor that could inhibit tumor metastasis from natural products. We demonstrated that pomolic acid (PA), a component of Euscaphis japonica, could downregulate CXCR4 expression in breast cancer cells. Treatment with proteasomal and lysosomal inhibitors did not show significant effects on PA's ability. When we further explored the molecular mechanism, suppression of CXCR4 occurred at transcriptional level and was correlated with inhibition of nuclear factor‐kappaB (NF‐κB) activation. Downregulation of CXCR4 by PA was accompanied by the inhibition of CXC motif chemokine 12 (CXCL12)‐induced invasion of breast cancer cells. Overall, our results indicate that PA, as a novel inhibitor of CXCR4, can be a promising therapeutic agent for treatment of cancer metastasis. J. Cell. Biochem. 117: 1296–1307, 2016. © 2015 Wiley Periodicals, Inc.
Ion strength limit of computed excess functions based on the linearized Poisson–Boltzmann equation
Authors: Fraenkel Dan
Published: October 2015

The linearized Poisson–Boltzmann (L‐PB) equation is examined for its κ‐range of validity (κ, Debye reciprocal length). This is done for the Debye–Hückel (DH) theory, i.e., using a single ion size, and for the SiS treatment (D. Fraenkel, Mol. Phys. 2010, 108, 1435), which extends the DH theory to the case of ion‐size dissimilarity (therefore dubbed DH–SiS). The linearization of the PB equation has been claimed responsible for the DH theory's failure to fit with experiment at > 0.1 m; but DH–SiS fits with data of the mean ionic activity coefficient, γ± (molal), against m, even at m > 1 (κ > 0.33 Å−1). The SiS expressions combine the overall extra‐electrostatic potential energy of the smaller ion, as central ion—Ψa>b(κ), with that of the larger ion, as central ion—Ψb>a(κ); a and b are, respectively, the counterion and co‐ion distances of closest approach. Ψa>b and Ψb>a are derived from the L‐PB equation, which appears to conflict with their being effective up to moderate electrolyte concentrations (≈1 m). However, the L‐PB equation can be valid up to κ ≥ 1.3 Å−1 if one abandons the 1/κ criterion for its effectiveness and, instead, use, as criterion, the mean‐field electrostatic interaction potential of the central ion with its ion cloud, at a radial distance dividing the cloud charge into two equal parts. The DH theory's failure is, thus, not because of using the L‐PB equation; the lethal approximation is assigning a single size to the positive and negative ions. © 2015 Wiley Periodicals, Inc.
A Green Mechanochemical Synthesis of New 3,5‐Dimethyl‐4‐(arylsulfanyl)pyrazoles
Authors: Saeed Aamer , Channar Pervaiz Ali
Published: October 2015

A small series of new 3,5‐dimethyl‐4‐(arylsulfanyl)pyrazoles have been synthesized in good to excellent yields by a grinding‐induced, sequential one‐pot three‐component reaction, of an equimolar mixture of 3‐chloro‐2,4‐pentanedione, differently substituted thiophenols, and hydrazine hydrate in the presence of piperidine under solvent‐free conditions.
Community, Conflict and Land: Exploring the Strategic Partnership Model of South African Land Restitution
Authors: Basu Soutrik
Published: October 2015

The Strategic Partnership (SP) model was implemented in the South African land restitution programme. The model prematurely ended in a fiasco that left the community with huge debts and intractable conflicts. This paper aims at understanding the implementation process by taking up the issue of how conflict emerged, resolved and sustained around the SP model. This paper suggests that conflict emerged because of the following reasons: the policy framework failed to address the heterogeneity of the community; community value was undermined as a business partner; and the state placed unprecedented trust, power, and authority on strategic partners. Copyright © 2015 John Wiley & Sons, Ltd.
Comparison of three human papillomavirus DNA detection methods: Next generation sequencing, multiplex‐PCR and nested‐PCR followed by Sanger based sequencing
Authors: da Fonseca Allex Jardim , Galvão Renata Silva , Miranda Angelica Espinosa , Ferreira Luiz Carlos de Lima , Chen Zigui
Published: October 2015

To compare the diagnostic performance for HPV infection using three laboratorial techniques. Ninty‐five cervicovaginal samples were randomly selected; each was tested for HPV DNA and genotypes using 3 methods in parallel: Multiplex‐PCR, the Nested PCR followed by Sanger sequencing, and the Next_Gen Sequencing (NGS) with two assays (NGS‐A1, NGS‐A2). The study was approved by the Brazilian National IRB (CONEP protocol 16,800). The prevalence of HPV by the NGS assays was higher than that using the Multiplex‐PCR (64.2% vs. 45.2%, respectively; P = 0.001) and the Nested‐PCR (64.2% vs. 49.5 %, respectively; P = 0.003). NGS also showed better performance in detecting high‐risk HPV (HR‐HPV) and HPV16. There was a weak interobservers agreement between the results of Multiplex‐PCR and Nested‐PCR in relation to NGS for the diagnosis of HPV infection, and a moderate correlation for HR‐HPV detection. Both NGS assays showed a strong correlation for detection of HPVs (k = 0.86), HR‐HPVs (k = 0.91), HPV16 (k = 0.92) and HPV18 (k = 0.91). NGS is more sensitive than the traditional Sanger sequencing and the Multiplex PCR to genotype HPVs, with promising ability to detect multiple infections, and may have the potential to establish an alternative method for the diagnosis and genotyping of HPV. J. Med. Virol. 88:888–894, 2016. © 2015 Wiley Periodicals, Inc.
Human bocavirus in children with acute gastroenteritis in Albania
Authors: La Rosa G. , Della Libera S. , Iaconelli M. , Donia D. , Cenko F. , Xhelilaj G. , Cozza P. , Divizia M.
Published: October 2015

Human Bocavirus (HBoV) has been recently identified in association with acute viral gastroenteritis (AGE). The objective of this work was to investigate the prevalence of HBoV in children with AGE in Albania. Stool specimens collected from 142 children were analyzed by amplification of partial NP1 and Vp1/Vp2 genes. HBoV was detected in 13 samples (9.1%), 12 HBoV‐1 and one HBoV‐2. All HBoV‐positive patients were co‐infected with rotavirus and/or adenovirus, a finding which might indicate that there is no clear causal association of this agent with diarrhea. Further investigation is needed to assess the pathogenic role of HBoV in childhood diarrhea. J. Med. Virol. 88:906–910, 2016. © 2015 Wiley Periodicals, Inc.
Differential vascular permeability along the forebrain ventricular neurogenic niche in the adult murine brain
Authors: Colín‐Castelán Dannia , Ramírez‐Santos Jesús , Gutiérrez‐Ospina Gabriel
Published: October 2015

Adult neurogenesis is influenced by blood‐borne factors. In this context, greater or lesser vascular permeability along neurogenic niches would expose differentially neural stem cells (NSCs), transit amplifying cells (TACs), and neuroblasts to such factors. Here we evaluate endothelial cell morphology and vascular permeability along the forebrain neurogenic niche in the adult brain. Our results confirm that the subventricular zone (SVZ) contains highly permeable, discontinuous blood vessels, some of which allow the extravasation of molecules larger than those previously reported. In contrast, the rostral migratory stream (RMS) and the olfactory bulb core (OBc) display mostly impermeable, continuous blood vessels. These results imply that NSCs, TACs, and neuroblasts located within the SVZ are exposed more readily to blood‐borne molecules, including those with very high molecular weights, than those positioned along the RMS and the OBc, subregions in which every stage of neurogenesis also takes place. These observations suggest that the existence of specialized vascular niches is not a precondition for neurogenesis to occur; specialized vascular beds might be essential for keeping high rates of proliferation and/or differential differentiation of neural precursors located at distinct domains. © 2015 Wiley Periodicals, Inc.
Identification and analysis of anthocyanin components in fruit color variation in Schisandra chinensis
Authors: Liao Jingjing , Zang Jian , Yuan Fei , Liu Shuang , Zhang Yibo , Li Haiyan , Piao Zhongyun , Li Hongbo
Published: October 2015

BACKGROUND

Fruit color is an important index and parameter for measuring fruit quality. As an important pigment, anthocyanin is a determinant which appears in all sorts of colors of fruits in nature.

RESULTS

Color parameters were measured using a spectrometer and used as a basis to divide the materials into three groups: reddish‐orange, orange and yellow. A validated high‐performance liquid chromatographic–electrospray ionization–mass spectrometric method was used for the analysis of anthocyanin in Schisandra chinensis and for determining major anthocyanin components in S. chinensis fruits, i.e. cyanidin xylosyl‐glucoside (CyXylGlu), cyanidin glucosyl‐rutinoside (CyGluRutin), cyanidin rutinoside (CyRutin) and cyanidin xylosyl‐rutinoside (CyXylRutin). The anthocyanin contents vary obviously in different colored fruits in S. chinensis. The impact of anthocyanin on coloration of fruits was investigated by multiple regression analysis between color parameters and anthocyanin components, which indicated that CyRutin is the primary cause of fruit color variation in S. chinensis.

CONCLUSION

The content and type of anthocyanin determine fruit coloration in S. chinensis, laying the early foundations for systematically interpreting the mechanism of fruit coloration in S. chinensis. © 2015 Society of Chemical Industry
Influence of the hydrophilic head size and hydrophobic tail length of surfactants on the ability of micelles to stabilize citral
Authors: Hong Chi Rac , Park Sung Joon , Choi Seung Jun
Published: October 2015

BACKGROUND

Surfactant‐made micelles can control the rate of chemical degradation of poorly water‐soluble food flavors. To evaluate how the molecular structure of surfactant has an influence on the chemical decomposition rate of citral, micelles were prepared with polyoxyethylene alkyl ether‐type surfactants that had similar molecular structures but various hydrophilic head sizes and hydrophobic tail lengths.

RESULTS

At a critical 20× micelle concentration of surfactant, there was no significant difference in the chemical degradation rate of citral in micelles in neutral pH, regardless of the hydrophilic head size or hydrophobic tail length. In an acidic environment, the degradation rate constant of citral generally increased proportionally with increasing hydrophilic head size of surfactant (0.1563 and 0.2217 for surfactants with 23 and 100 oxyethylene units, respectively) but the length of hydrophobic tail did not affect the citral stability. Also, little difference (0.2217 and 0.2265 for surfactant having 100 oxyethylene units with and without Fe3+) in degradation rate constant of citral between simple micellar solution and micellar solution containing iron suggested that iron ions could not accelerate citral degradation in micelles, regardless of the form of iron (Fe2+ and Fe3+).

CONCLUSION

This work concludes that although the concentration of surfactant could be relevant, if its concentration could be controlled in the same manner as the critical micelle concentration, then a polyethylene alkyl ether‐type surfactant with a small hydrophilic head could more efficiently stabilize citral at an acidic pH. © 2015 Society of Chemical Industry
Finite element analysis of quasi‐static indentation of woven fabric textile composites using different nose shape indenters
Authors: Dixit A. , Misra R. K. , Mali H. S.
Published: October 2015

The finite element FE analysis of quasi‐static indentation event of various nose shape rigid indenters into woven fabric composite with carbon fiber as reinforcement has been performed and discussed in detail. It was found that indenter nose shape has large influence in terms of absorbed energy, indentation at failure and damage area. The FE software, ABAQUS® was employed to simulate quasi‐static response of woven composite unit cell. Exhaustive parametric studies have been conducted with an aim to analyze the effect of change in indenter geometry on the indentation response of the woven composite unit cell. The developed FE model for the purpose of validation was compared with available experimental results and was found to be in reasonably good agreement. The failure morphologies, damage shape and damage size were evaluated, compared and deeply discussed for different nose shape indenters. Largest damaged areas were observed for flat and truncated indenters while the smallest for the conical one.