bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resveratrol derivatives from Commiphora africana (A. Rich.) Endl. display cytotoxicity and selectivity against several human cancer cell lines
Authors: Segun Peter A. , Ogbole Omonike O. , Ismail Fyaz M.D. , Nahar Lutfun , Evans Andrew R. , Ajaiyeoba Edith O. , Sarker Satyajit D. 
Published: October 2018

Commiphora africana (A. Rich.) Endl. (Burseraceae) is a medicinal plant widely used in Nigerian ethnomedicine. The in vitro cytotoxicity of the stem bark extract of C. africana and isolated cytotoxic compounds was investigated. Three resveratrol derivatives: (E)‐resveratrol 3‐O‐rutinoside (1), 5‐methoxy‐(E)‐resveratrol 3‐O‐rutinoside (2), and pinostilbene (3), together with 3‐hydroxy‐5‐methoxybenzoic acid (4) were isolated from the methanol fraction of C. africana. Their structures were determined by extensive analysis of their HREIMS and NMR spectra. The cytotoxicity of the isolated compounds against four human carcinoma cells was determined using the MTT assay. Compound 1 displayed the highest antiproliferative effect on the cell lines, with IC50 values of 16.80, 21.74, 17.89, and 17.44 μM, against MCF7, A549, PC3, and HepG2 human cancer cell lines, respectively. In addition, compounds 1–3 showed low toxicity against normal human prostate cell line, with selectivity indices greater than five across the carcinoma cells, indicating that the compounds possess potential in the development of low‐toxicity chemotherapeutic agents. These results support the traditional use of this plant in the treatment of cancer.
Vapor Phase Selective Production of Ethyl Lactate over ZrO2‐SiO2 Catalysts Using Lactic Acid and Ethanol
Authors: Peddinti Nagaiah , Venkata Pramod Chodimella , Challa Prathap , Burri David Raju , Kamaraju Seetha Rama Rao 
Published: October 2018

AbstractA series of zirconia‐silica catalysts with different weight % of ZrO2 were prepared by sol‐gel method and tested for the vapor phase production of ethyl lactate via esterification of lactic acid using ethanol. Under the optimized conditions, 99% selectivity to ethyl lactate and complete conversion of lactic acid is observed over 7% ZrO2/SiO2 catalyst at 453 K with 1:15 molar ratio of lactic acid and ethanol. The catalysts were studied for various properties using XRD, FTIR, NH3‐TPD, N2 sorption, Pyridine FT‐IR and UV‐Vis. The results revealed that 7% ZrO2/SiO2 possesses amorphous phase and sufficient number of acidic sites which are helpful in achieving higher activity.
Continuous Production of 5‐Hydroxymethylfurfural from Monosaccharide over Zirconium Phosphates
Authors: Zhu Changhui , Cai Chiliu , Liu Qiying , Li Wenzhi , Tan Jin , Wang Chenguang , Chen Lungang , Zhang Qi , Ma Longlong 
Published: October 2018

Abstract5‐hydroxymethylfurfural (HMF), an important platform compound produced from lignocellulosic biomass, is widely applied in petrochemical industry for downstream synthesis of medical supplies or intermediate of the other important chemicals by the typical catalytic processes. A continuous production route was developed to yield HMF from monosaccharides by using zirconium phosphate (ZrP) with different Zr/P ratios as catalysts. Its physicochemical properties were then characterized by Brunauer‐Emmett‐Teller (BET), X‐ray powder diffraction (XRD), X‐ray photoelectron spectra (XPS), Fourier transform infrared spectroscopy (FT‐IR), pyridine adsorbed Fourier transform infrared spectroscopy (Py‐FT‐IR), X‐ray fluorescence (XRF) and temperature programmed desorption of ammonia (NH3‐TPD) techniques. A mixed phase containing monosaccharide in aqueous and dimethyl sulfoxide (DMSO) phase was applied in the fixed bed to keep the continuous production. The optimized reaction conditions were applied to maximized HMF yield by varying the processing parameters. The highest HMF yield of 56.3% was obtained when using fructose as the feedstock under the reaction condition of 120 °C, 180 min, N2 pressure 2 MPa and DMSO: fructose solution of 9:1 over ZrP with the P/Zr with molar ratio of 2. Comparatively, the glucose conversion of 72% with the HMF yield of 32% were gained under the same conditions using glucose as the feedstock. It is deduced that the ZrP catalysts simultaneously possessing Brönsted/Lewis acid showed synergy in glucose dehydration to HMF. The ZrP catalyst showed good stability and no obvious deactivation was observed after 30 h of time‐on‐stream, due to the primary structure and acidic properties of catalyst can be kept during the reaction. Finally, it is generally efficient for some C6 sugars dehydration to HMF with the Brönsted/Lewis acid synergy of ZrP.
Asymmetric Color‐Changeable Luminophore with Donor–Acceptor–Donor Structure for Solvent and Temperature Sensitive Properties
Authors: Kitagawa Yuichi , Yachi Ryuto , Nakanishi Takayuki , Fushimi Koji , Hasegawa Yasuchika 
Published: October 2018

AbstractAn asymmetric donor–acceptor–donor (D–A–D) type organic luminophore is reported for solvent and temperature sensors. The electronic absorption and luminescence properties of the luminophore were assessed from its electronic absorption and luminescence spectra, which depended on the external environment. The D–A–D luminophore showed environment‐sensitive charge transfer fluorescence based on structural transformation through excited singlet states. Characteristic D–A–D phosphorescence was also observed at 494 nm, which was shorter than that of the D–A–D fluorescence (502 nm). In this study, the novel photophysical properties of a D–A–D‐type luminophore induced by its asymmetric electronic structure are described.
Facile Synthesis of Ag‐TiO2 Hybrid Nanocluster:A Comprehensive Experimental and Computational Insight into the Role of Surface Ligands on Enhanced Visible Light Photo‐catalysis
Authors: Goswami Tapas , Singh Manjeet , Reddy K. Mohan , Mishra Abhishek K. 
Published: October 2018

AbstractOwing to their ultrafine size, biocompatibility and excellent photo‐stability, metallic nanoclusters are promising materials which could be combined with ultra‐small TiO2 to discover a new class of hybrid nanomaterial with unique photocatalytic and self‐cleaning properties. A lot of effort has been made very recently to combine silver nanoclusters (AgNC) with titania and hence size and composition controlled electronic and catalytic properties. However, most of the methods used extended network of titania to support AgNC and individual titania functionalized AgNC is rarely observed. In the present study, we report a new low temperature method of preparation of ultra‐small TiO2 functionalized AgNC ligated with glutathione. AgNC alone shows negligible visible light photocatalysis whereas incorporation of ultra‐small titania, lowers the bandgap of the hybrid nanocluster and facilitate solar activation leading to enhanced catalytic activity. Visible light induced catalytic property of hybrid NCs are investigated in degradation of a model dye, Rhodamine B (RhB). Simple structural models Agm(SCH3)n‐TiO2 are used to explore the interaction of surface ligands with TiO2 molecule using Density Functional Theory (DFT) calculations. The calculated absorption spectra using Time Dependent Density Functional Theory (TD‐DFT) have been used for monitoring the spectral shifts of characteristics absorption bands towards visible region.
β‐Cyclodextrin Monosulphonic Acid Promoted Multicomponent Synthesis of 1,8‐Dioxodecahydroacridines in Water
Authors: Madankumar Natarajan , Pitchumani Kasi 
Published: October 2018

AbstractA simple and efficient route for the synthesis of 1,8‐dioxodecahydroacridine derivatives in water is described using β‐cyclodextrin monosulphonic acid (prepared readily from β‐cyclodextrin obtained by enzymatic degradation of starch and chlorosulphonic acid), as an environmentally friendly acid catalyst. In this one‐pot method, 1,8‐dioxodecahydroacridine derivatives (19 compounds) are synthesized from dimedone, ammonium chloride and aromatic aldehydes in high yields (upto 94 %). All the synthesized compounds are extensively characterized by 1H and 13C‐NMR, ESI‐MS and also by their melting points. A plausible mechanism involving a multifunctional role for β‐cyclodextrin monosulphonic acid is proposed. The other key benefits and green credentials of this protocol are nitrogen assimilation (formation of organic nitrogen compounds from ammonium chloride in laboratory), use of water which is an environmentally benign solvent, solid acid catalyst, easy workup, reusability upto five times, milder reaction conditions and broad substrate scope.
A Robust Integrated SnOx/Carbon Composite Anode for Sodium‐Ion Batteries
Authors: Xu Jia , Shen Lu , Shi Kai , Cao Tengfei , Lv Wei , He Yan‐Bing 
Published: October 2018

AbstractTin (Sn) has been considered as a promising anode material for sodium ion battery due to its high specific capacity. However, its poor cycling stability and rate performance hinders the real application. Inspired by the structure of reinforced concrete and tunnel, an integrated SnOx/carbon composite anode was designed for high performance sodium ion batteries. In this structure, the SnOx nanoparticles were embedded in the amorphous carbon with interconnected pores derived from carbonization of the polyacrylonitrile (PAN) and starch, where the amorphous carbon can buffer the bulk expansion of SnOx to maintain structural stability and the interconnected pores can store the electrolyte to promote the sodium ion transportation for high rate reaction of the SnOx particles with sodium ion. The reduced graphene oxide as robust framework similar with rebar is inserted into the amorphous carbon/SnOx composite to enhance the stability and conductivity of composite. The starch as pore‐creating additive is decomposed during high‐heat treatment to form interconnected tunnel‐like pores in SnOx/carbon composite for electrolyte storage and high efficient sodium ion transportation. As a result, the as‐prepared integrated SnOx/carbon composite anode shows outstanding rate and cycling performance. Constructing the interconnected pore in SnOx/carbon composite using starch can greatly improve its charge specific capacity and rate performance.
2‐Hydroxyethyl‐Substituted (NHC)Pd(II)PPh3 Complexes: Synthesis, Characterization, Crystal Structure and Its Application on Sonogashira Cross‐Coupling Reactions in Aqueous Media
Authors: Aktaş Aydın , Celepci Duygu Barut , Gök Yetkin , Aygün Muhittin 
Published: October 2018

AbstractThis study contains the synthesis of the novel series of the 2‐ hydroxyethyl substituted Pd‐based N‐heterocyclic carbene (NHC) / triphenylphosphine (PPh3) complexes. The (NHC)Pd(II)PPh3 complexes have been prepared from the PPh3 ligand, replaced by 3‐chloro pyridine ligand in (NHC)Pd(II)(3‐Cl‐pyridine) complexes. The novel 2‐hydroxyethyl substituted (NHC)Pd(II)PPh3 complexes have been characterized by using 1H NMR, 13C {1H}NMR, 31P {1H}NMR, FTIR spectroscopy, and elemental analysis techniques. Molecular and crystal structure of 1 f was obtained by using single‐crystal X‐ray diffraction method. The novel 2‐hydroxyethyl substituted (NHC)Pd(II)PPh3 complexes have been examined as catalysts in the Sonogashira cross‐coupling reactions aqueous medium and demonstrated excellent activity in this reaction.
Investigation on the Nucleation Stage of Palladium Nanoparticles Using a Microfluidic Droplet Generator Integrated with In Situ Sol‐Gel Quencher
Authors: Bae Sunwoong , Jung Euiyoung , Yu Taekyung , Seo Tae Seok 
Published: October 2018

AbstractThe nanoparticle (NP) synthesis undergoes stepwise processes starting from the input metal ions: nucleation, coalescence, ripening, and growth. Considering the whole process is completed in a very short time, the conventional flask‐scale method, which requires at least minutes, is not adequate to trace the mechanism of NP nucleation. In this study, a microfluidic droplet generator is developed, which is capable of in situ sol–gel polymerization for synthetic reaction quenching. As a model, palladium (Pd) NPs are synthesized within microdroplets, and the reaction time is controlled by tuning the length of the microchannel. In the microfluidic design, the outmost microchannel is incorporated, in which tetraethyl orthosilicate (TEOS) dissolved in ethanol is injected. The generated droplets are merged to the outmost flow under the variety of time interval (50 to 5,000 ms), so that the tens of milliseconds observation on NP nucleation is conducted via flash‐like sol–gel quenching. Based on the result analysis, the seeds of Pd NPs have undergone slight size fluctuation and then a thermodynamically stable aggregation/coalescence step within 5 s before moving into the growth stage. This microfluidic platform permits the study of the fundamental and initial stage of the NP synthesis, which cannot be approached by the conventional methodology.
Dhh1 is a member of the SESA network
Authors: Ergüden Bengü 
Published: October 2018

AbstractThe correct separation of chromosomes during mitosis is necessary to prevent genetic instability and aneuploidy, which are responsible for cancer and other diseases, and it depends on proper centrosome duplication. In a recent study, we found that Smy2 can suppress the essential role of Mps2 in the insertion of yeast centrosome into the nuclear membrane by interacting with Eap1, Scp160, and Asc1 and designated this network as SESA (Smy2, Eap1, Scp160, Asc1). Detailed analysis showed that the SESA network is part of a mechanism which regulates translation of POM34 mRNA. Thus, SESA is a system that suppresses spindle pole body duplication defects by repressing the translation of POM34 mRNA. In this study, we performed a genome‐wide screening in order to identify new members of the SESA network and confirmed Dhh1 as a putative member. Dhh1 is a cytoplasmic DEAD‐box helicase known to regulate translation. Therefore, we hypothesized that Dhh1 is responsible for the highly selective inhibition of POM34 mRNA by SESA.
Corporate reputation in management research: a review of the literature and assessment of the concept
Authors: Veh Annika , Göbel Markus , Vogel Rick 
Published: October 2018

AbstractThe study of reputation figures prominently in management research, yet the increasing number of publications makes it difficult to keep track of this growing body of literature. This paper provides a systematic review of the literature based on a large-scale bibliometric analysis. We draw on bibliographic data of 5885 publications published until 2016, inclusively, and combine co-citation analysis and bibliographic coupling with network visualization. Results show how research on corporate reputation is embedded in the broader field of scholarship on reputation in general. When zooming into the publication cluster on corporate reputation more closely, the concept’s origins in economics, organizational studies, and marketing as well as corresponding theoretical and methodological discussions are revealed. Beyond providing a structured overview of the field, the bibliometric analyses also reveal conceptual incoherencies that lead to ambiguities in research. Our assessment builds on the philosophy of science and is guided by the criteria of good concepts in social sciences. It shows that the concept of corporate reputation lacks internal coherence and could have more theoretical utility. We recommend focusing on corporate reputation as an attitudinal concept and thereby emphasizing the stakeholder who acts as an evaluator of the corporation.
Selling the product: Strategies to increase recruitment and retention of Spanish-speaking Latinos in biomedical research
Authors: Rhodes Scott D. , Alonzo Jorge , Mann-Jackson Lilli , Tanner Amanda E. , Vissman Aaron T. , Martinez Omar , Rodriguez-Celedon Rodrigo , Garcia Jesus M. , Arellano Hall Jorge E. , Song Eunyoung Y. , Eng Eugenia , Reboussin Beth A. 
Published: October 2018

IntroductionThe Latino population in the United States is rapidly growing and faces profound health disparities; however, engagement of Latinos in biomedical research remains low. Our community-based participatory research partnership has recruited 2083 Spanish-speaking Latinos into 21 studies over 15 years. We sought to identify and describe the strategies we have used to successfully recruit and retain Spanish-speaking Latinos in research.MethodsWe abstracted and analyzed data from archived study notes, progress reports, team meeting minutes, and in-depth interviews conducted annually from community-based participatory research partnership members. We used a nominal group process to refine and prioritize strategies.ResultsOverall, 13 recruitment strategies and 12 retention strategies emerged. These strategies relied on the creativity and perseverance of the study team and partners.ConclusionsIt is essential that we develop and disseminate effective recruitment and retention strategies that engage Latinos in biomedical research to reduce health disparities and promote health equity.
Economic Expectations and Satisfaction with Democracy: Evidence from Italy
Authors: Loveless Matthew , Binelli Chiara 
Published: October 2018

AbstractIn this article, we argue that individuals’ expectations about their future economic prospects are a crucial missing determinant of their degree of satisfaction with democracy. To investigate this link, we collected an original, nationally representative data set on young skilled unemployed Italians using the innovative quantitative expectations data methodology (Manski 2004). Controlling for current local labour market conditions with administrative province-level data and for a rich array of individual-level determinants, we show that those expecting greater job insecurity and instability have lower current satisfaction levels with democracy. By better conceptualizing and operationalizing individuals’ expectations, we advance the theoretical framework on satisfaction with democracy and show that expectations are an important and often overlooked determinant of the current level of satisfaction with democratic institutions.
Glacier branch lines and glacier ice thickness estimation for debris-covered glaciers in the Central Tien Shan
Authors: PIECZONKA TINO , BOLCH TOBIAS , KRÖHNERT MELANIE , PETERS JULIANE , LIU SHIYIN 
Published: October 2018

ABSTRACTInformation about the ice volume stored in glaciers is of high importance for sustainable water management in many arid regions of Central Asia. Several methods to estimate the ice volume exist. However, none of them take the specific characteristics of flat terminus debris-covered glaciers into account. We present a method for deriving spatially-distributed ice thickness for debris-covered dendritic glaciers, which are common not only in Central Tien Shan but also in several other mountain ranges in High Asia. The method relies on automatically generated branch lines, observed surface velocities and surface topographic parameters as basic input. Branch lines were generated using Thiessen polygons and Dijkstra's path algorithm. Ice thicknesses for four debris-covered glaciers – South Inylchek, Kaindy, Tomur and Koxkar glaciers – have been estimated along the branch line network solving the equation of laminar flow. For Koxkar and South Inylchek glaciers, respectively, maximum thicknesses of ~250 and 380 m were estimated. These results differ by ~50 m compared with GPR measurements with an uncertainty for the debris-covered parts of ~40%. Based on geodetic mass balances, we estimate that the investigated glaciers lost between 6 and 28% of their volume from 1975 to the early 2000s.
Polarization and Electoral Incentives: The End of the Chilean Consensus Democracy, 1990–2014
Authors: Fábrega Jorge , González Jorge , Lindh Jaime 
Published: October 2018

AbstractConsensus democracy among the main Chilean political forces ended abruptly after the 2013 presidential and parliamentary elections, the most polarized elections since the return to democracy in 1990. Relying on spatial voting theory to uncover latent ideological dimensions from survey data between 1990 and 2014, this study finds patterns of gradual polarization starting at least ten years before the collapse of consensus, based on an increasing demobilization of the political center that misaligned politicians from their political platforms (particularly in the center-left parties). That phenomenon changed the political support for the two main political coalitions and the intracoalition bargaining power of their various factions. The pattern also helps to explain the process behind the 2015 reform of the electoral system.
The Deep Roots of Protectionism in the Southern Cone: Constituent Interests and Mercosur’s Common External Tariff
Authors: Pezzola Anthony A. 
Published: October 2018

AbstractThis article examines the influence of subnational economic interests on the formation of supranational trade policy in the Southern Common Market (Mercosur). Accounting for differences in the relative importance of member countries, the article argues that subnational economic interests influenced the structure of Mercosur’s common external tariff (CET). Although the CET was negotiated without direct input from voters or legislators, its structure reflects the interests of geographically specific economic interests in the member countries. The results of a regression analysis of tariffs toward nonmembers indicate that the economic composition of subnational political jurisdictions shaped the structure of the CET. These findings suggest that by overlooking subnational economic interests, much of the current literature on the evolution of Mercosur misses a critical aspect of the policymaking process.
A sociophonetic account of onset /s/ weakening in Salvadoran Spanish: Instrumental and segmental analyses
Authors: Brogan Franny D. , Bolyanatz Mariška A. 
Published: October 2018

AbstractIn this study, we identify the linguistic and social predictors that condition onset /s/ weakening in speech data from sociolinguistic interviews with 72 Salvadoran Spanish speakers. In addition, we compare and contrast the explanatory power of instrumental and traditional segmental approaches. We find that the instrumental approach, which identifies flanking segments, stress, and region of origin of the speaker as conditioners of onset /s/ shortening and lowering of center of gravity, does not account for observed social variation in the data. Contrastingly, an ordinal logistic regression based on a combination of instrumental measures and perceived phonetic categories identifies flanking segment, region of origin, sex, and age of the speaker as predictors of onset /s/ weakening. We conclude that an exclusively instrumental analysis examining variation of onset /s/ thus obscures the potential social meaning of onset /s/ weakening in El Salvador.
Stylistic variation among mobile speakers: Using old and new regional variables to construct complex place identity
Authors: Nycz Jennifer 
Published: October 2018

AbstractThis paper examines stylistic variation in the (oh), (o), (aw), and (ay) classes among native speakers of Canadian English living in or just outside either New York City or Washington, DC. Speakers show evidence of change toward US norms for all four vowels, though only (aw) shows consistent style shifting: prevoiceless (aw) is realized with higher nuclei when speakers express ambivalence about or distance from the United States, and lower nuclei when closeness to or positive affect about the United States is being conveyed. Canadians in New York also show topic- and stance-based shift in (oh): (oh)s are higher when expressing positive affect or closeness to New York City and lower when expressing negative affect or distance. These results suggest that mobile speakers continue to exploit the socioindexical links in their native dialect while learning and using new links in their adopted dialect—but only if those links are socially salient.