bluuebunny/crossref_metadata_2025 huggingface dataset:
Crystal structure and dynamics of a lipid-induced potential desensitized-state of a pentameric ligand-gated channel
Authors: Basak Sandip , Schmandt Nicolaus , Gicheru Yvonne , Chakrapani Sudha
Published: March 2017

Desensitization in pentameric ligand-gated ion channels plays an important role in regulating neuronal excitability. Here, we show that docosahexaenoic acid (DHA), a key ω−3 polyunsaturated fatty acid in synaptic membranes, enhances the agonist-induced transition to the desensitized state in the prokaryotic channel GLIC. We determined a 3.25 Å crystal structure of the GLIC-DHA complex in a potentially desensitized conformation. The DHA molecule is bound at the channel-periphery near the M4 helix and exerts a long-range allosteric effect on the pore across domain-interfaces. In this previously unobserved conformation, the extracellular-half of the pore-lining M2 is splayed open, reminiscent of the open conformation, while the intracellular-half is constricted, leading to a loss of both water and permeant ions. These findings, in combination with spin-labeling/EPR spectroscopic measurements in reconstituted-membranes, provide novel mechanistic details of desensitization in pentameric channels.
Laparoscopic Treatment of Primary Hydatid Cyst of Omentum
Authors: Ertugrul Ismail , Kayaalp Cuneyt , Dirican Abuzer , Tardu Ali , Karagul Servet , Kirmizi Serdar
Published: March 2017

Omental hydatid cysts usually secondarily exist after the spontaneous, traumatic, or iatrogenic perforation of primary abdominal hydatid cysts. An isolated omental hydatid cyst in the absence of other organ involvement is very rare. Here, we present a 49-year-old male with a primary omental hydatid cyst. He was living in an urban area, but he spent his childhood in rural areas and worked with livestock. The differential diagnosis was not easy because of the negative serological test. Laparoscopic exploration revealed the diagnosis of hydatid cyst and it was removed by laparoscopy without spillage of the cyst contents. After the total excision, no albendazole treatment was prescribed. Isolated omental hydatid cysts should be in the differential diagnosis of the peritoneal cysts and its laparoscopic total excision is a feasible treatment.
Tides and Water Levels
Authors: Haigh Ivan D.
Published: March 2017

Sea level relates to the vertical change in height of the sea surface, which occurs over all time and space scales. The observed sea level (excluding wind waves) can be regarding as being the combination of tides, nontidal residuals, and mean sea level. Tides are the most predictable and dominant component of sea‐level fluctuations in many parts of the world. To fully understand, predict, and categorize them, one must understand both the astronomical forcing that gives rise to them and also the hydrodynamic response of the oceans, to this forcing. The nontidal residual is the part of the sea level that remains once the tidal component has been removed and primarily contains the meteorological contribution to sea level. The most dramatic meteorological sea‐level changes occur during storms, when low atmospheric pressure allows sea level to rise and strong winds force water toward the coastline. Mean sea level is the average height of the sea over longer periods of time with the short‐term variations associated with tide and storm surges averaged out. The main climate‐related factors that are currently causing mean sea levels to rise are: the melting of land‐based sources of ice; thermal expansion of seawater; and changes in terrestrial hydrological regimes.
The facial width‐to‐height ratio determines interpersonal distance preferences in the observer
Authors: Lieberz Klara A. , Windmann Sabine , Geniole Shawn N. , McCormick Cheryl M. , Mueller‐Engelmann Meike , Gruener Felix , Bornefeld‐Ettmann Pia , Steil Regina
Published: March 2017

Facial width‐to‐height ratio (fWHR) is correlated with a number of aspects of aggressive behavior in men. Observers appear to be able to assess aggressiveness from male fWHR, but implications for interpersonal distance preferences have not yet been determined. This study utilized a novel computerized stop‐distance task to examine interpersonal space preferences of female participants who envisioned being approached by a man; men's faces photographed posed in neutral facial expressions were shown in increasing size to mimic approach. We explored the effect of the men's fWHR, their behavioral aggression (measured previously in a computer game), and women's ratings of the men's aggressiveness, attractiveness, and masculinity on the preferred interpersonal distance of 52 German women. Hierarchical linear modelling confirmed the relationship between the fWHR and trait judgements (ratings of aggressiveness, attractiveness, and masculinity). There were effects of fWHR and actual aggression on the preferred interpersonal distance, even when controlling statistically for men's and the participants’ age. Ratings of attractiveness, however, was the most influential variable predicting preferred interpersonal distance. Our results extend earlier findings on fWHR as a cue of aggressiveness in men by demonstrating implications for social interaction. In conclusion, women are able to accurately detect aggressiveness in emotionally neutral facial expressions, and adapt their social distance preferences accordingly.
Conductivity and Local Structure of LaNiO3 Thin Films
Authors: Fowlie Jennifer , Gibert Marta , Tieri Giulio , Gloter Alexandre , Íñiguez Jorge , Filippetti Alessio , Catalano Sara , Gariglio Stefano , Schober Alexander , Guennou Mael , Kreisel Jens , Stéphan Odile , Triscone Jean‐Marc
Published: March 2017

A marked conductivity enhancement is reported in 6–11 unit cell LaNiO3 thin films. A maximal conductivity is also observed in ab initio calculations for films of the same thickness. In agreement with results from state of the art scanning transmission electron microscopy, the calculations also reveal a differentiated film structure comprising characteristic surface, interior, and heterointerface structures. Based on this observation, a three‐element parallel conductor model is considered and leads to the conclusion that the conductivity enhancement for films of 6–11 unit cells, stems from the onset of intercompetition between the three local structures in the film depth.
Compromise and Synergy in High‐Efficiency Thermoelectric Materials
Authors: Zhu Tiejun , Liu Yintu , Fu Chenguang , Heremans Joseph P. , Snyder Jeffrey G. , Zhao Xinbing
Published: March 2017

The past two decades have witnessed the rapid growth of thermoelectric (TE) research. Novel concepts and paradigms are described here that have emerged, targeting superior TE materials and higher TE performance. These superior aspects include band convergence, “phonon‐glass electron‐crystal”, multiscale phonon scattering, resonant states, anharmonicity, etc. Based on these concepts, some new TE materials with distinct features have been identified, including solids with high band degeneracy, with cages in which atoms rattle, with nanostructures at various length scales, etc. In addition, the performance of classical materials has been improved remarkably. However, the figure of merit zT of most TE materials is still lower than 2.0, generally around 1.0, due to interrelated TE properties. In order to realize an “overall zT > 2.0,” it is imperative that the interrelated properties are decoupled more thoroughly, or new degrees of freedom are added to the overall optimization problem. The electrical and thermal transport must be synergistically optimized. Here, a detailed discussion about the commonly adopted strategies to optimize individual TE properties is presented. Then, four main compromises between the TE properties are elaborated from the point of view of the underlying mechanisms and decoupling strategies. Finally, some representative systems of synergistic optimization are also presented, which can serve as references for other TE materials. In conclusion, some of the newest ideas for the future are discussed.
Label‐Free and Regenerative Electrochemical Microfluidic Biosensors for Continual Monitoring of Cell Secretomes
Authors: Shin Su Ryon , Kilic Tugba , Zhang Yu Shrike , Avci Huseyin , Hu Ning , Kim Duckjin , Branco Cristina , Aleman Julio , Massa Solange , Silvestri Antonia , Kang Jian , Desalvo Anna , Hussaini Mohammed Abdullah , Chae Su‐Kyoung , Polini Alessandro , Bhise Nupura , Hussain Mohammad Asif , Lee HeaYeon , Dokmeci Mehmet R. , Khademhosseini Ali
Published: March 2017

Development of an efficient sensing platform capable of continual monitoring of biomarkers is needed to assess the functionality of the in vitro organoids and to evaluate their biological responses toward pharmaceutical compounds or chemical species over extended periods of time. Here, a novel label‐free microfluidic electrochemical (EC) biosensor with a unique built‐in on‐chip regeneration capability for continual measurement of cell‐secreted soluble biomarkers from an organoid culture in a fully automated manner without attenuating the sensor sensitivity is reported. The microfluidic EC biosensors are integrated with a human liver‐on‐a‐chip platform for continual monitoring of the metabolic activity of the organoids by measuring the levels of secreted biomarkers for up to 7 d, where the metabolic activity of the organoids is altered by a systemically applied drug. The variations in the biomarker levels are successfully measured by the microfluidic regenerative EC biosensors and agree well with cellular viability and enzyme‐linked immunosorbent assay analyses, validating the accuracy of the unique sensing platform. It is believed that this versatile and robust microfluidic EC biosensor that is capable of automated and continual detection of soluble biomarkers will find widespread use for long‐term monitoring of human organoids during drug toxicity studies or efficacy assessments of in vitro platforms.
Progress in Tandem Solar Cells Based on Hybrid Organic–Inorganic Perovskites
Authors: Chen Bo , Zheng Xiaopeng , Bai Yang , Padture Nitin P. , Huang Jinsong
Published: March 2017

Owing to their high efficiency, low‐cost solution‐processability, and tunable bandgap, perovskite solar cells (PSCs) made of hybrid organic‐inorganic perovskite (HOIP) thin films are promising top‐cell candidates for integration with bottom‐cells based on Si or other low‐bandgap solar‐cell materials to boost the power conversion efficiency (PCE) beyond the Shockley‐Quiesser (S‐Q) limit. In this review, recent progress in such tandem solar cells based on the emerging PSCs is summarized and reviewed critically. Notable achievements for different tandem solar cell configurations including mechanically‐stacked, optical coupling, and monolithically‐integrated with PSCs as top‐cells are described in detail. Highly‐efficient semitransparent PSC top‐cells with high transmittance in near‐infrared (NIR) region are critical for tandem solar cells. Different types of transparent electrodes with high transmittance and low sheet‐resistance for PSCs are reviewed, which presents a grand challenge for PSCs. The strategies to obtain wide‐bandgap PSCs with good photo‐stability are discussed. The PCE reduction due to reflection loss, parasitic absorption, electrical loss, and current mismatch are analyzed to provide better understanding of the performance of PSC‐based tandem solar cells.
When Research “Unravels”: One Community Psychologist's Tale of Becoming a Nepantlera
Authors: Silva Janelle M.
Published: March 2017

This is an autoethnography of one community psychologist's reflections on the abrupt conclusion of a project that resulted in the dismantlement of a Latinx Student Union at a public middle school in the Pacific Northwest. Gloria Anzaldúa's (Borderlands/La Frontera: The new mestiza, Aunt Lute Books, San Francisco, 2002) notion of nepantla is used to situate how an individual's personal identities often intersects with their professional identities in ways that collide within the research environment. Drawing on the “heart work” core competencies within the field of community psychology (The Community Psychologist, 45, 2012, 8; American Journal of Community Psychology, 55, 2015, 266) and extending the dialogue of feminist community psychologists engaged in narrative work (American Journal of Community Psychology, 37, 2006, 157; American Journal of Community Psychology, 37, 2006, 267; Feminist research practice: A primer, Sage, Los Angeles, 2014; American Journal of Community Psychology, 28, 2000, 883), the author addresses why it is important for researchers of Color engaged in community collaborations to reflect on projects that have unraveled to understand how their positionality shifts within social contexts.
Brønsted‐Acid‐Catalyzed Multicomponent One‐Pot Reaction: Efficient Synthesis of Polysubstituted 1,2‐Dihydropyridines
Authors: Xie Yi‐Bi , Ye Si‐Pei , Chen Wei‐Feng , Hu Yu‐Lin , Li De‐Jiang , Wang Long
Published: March 2017

An efficient method for the synthesis of 1,2‐dihydropyridine derivatives from simple and readily available aromatic ketones, DMF, amines and propargylic alcohols has been developed via a Brønsted‐acid‐catalyzed multicomponent one‐pot reaction. This reaction proceeded smoothly under metal‐ and ligand‐free conditions in good yields, leading to functional organic molecules, via a self‐organized sequence.
Efficient Construction of Well‐Defined Multicompartment Porous Systems in a Modular and Chemically Orthogonal Fashion
Authors: Gao Ning , Tian Tian , Cui Jiecheng , Zhang Wanlin , Yin Xianpeng , Wang Shiqiang , Ji Jingwei , Li Guangtao
Published: March 2017

A microfluidic assembly approach was developed for efficiently producing hydrogel spheres with reactive multidomains that can be employed as an advantageous platform to create spherical porous networks in a facile manner with well‐defined multicompartments and spatiotemporally controlled functions. This strategy allows for not only large scale fabrication of various robust hydrogel microspheres with controlled size and porosity, but also the domains embedded in hydrogel network could be introduced in a modular manner. Additionally, the number of different domains and their ratio could be widely variable on demand. More importantly, the reactive groups distributed in individual domains could be used as anchor sites to further incorporate functional units in an orthogonal fashion, leading to well‐defined multicompartment systems. The strategy provides a new and efficient route to construct well‐defined functional multicompartment systems with great flexibility and extendibility.
Using body donor demographics to assist the implementation of donation programs in Brazil
Authors: da Rocha Andrea Oxley , de Campos Deivis , Farina Marco Aurélio , Pacini Gabriel Sartori , Girotto Marina Cornelli , Hilbig Arlete
Published: March 2017

The use of human material in anatomy education depends upon the generosity of body donors. However, little is known regarding the demographics of body donors in Brazil, where voluntary body donation is a relatively rare phenomenon. Hence, the aim of the present study was to elucidate the demographic profile of applicants to the Body Donation Program (BDP) at the Federal University of Health Sciences of Porto Alegre in Brazil, as well as to assess whether the observed characteristics of body donors are unique to that sample, or if they merely reflect the characteristics of the regional population. Information derived from the specific forms filled out by donors between January 2008 and June 2016 at the time of registration were collected. Data from 416 forms were analyzed. Based on this study, the typical applicant in Brazil is typically a white female (67.4%), over 60 years of age (60.3%), unmarried or single (70.6%), affiliated with a religious group (89.1%), of middle class background (40.4%), who has completed high school and/or holds a university degree (93.8%). The motivation of donors was, in most cases, an altruistic gesture, represented by the desire to help society and science. Elucidating these demographic characteristics of potential donors may help identify the target public to which information regarding body donation campaigns could be directed. Anat Sci Educ 10: 475–486. © 2017 American Association of Anatomists.
Mixture Markov regression model with application to mosquito surveillance data analysis
Authors: Gao Xin , Cao Yurong R. , Ogden Nicholas , Aubin Louise , Zhu Huaiping P.
Published: March 2017

A mixture Markov regression model is proposed to analyze heterogeneous time series data. Mixture quasi‐likelihood is formulated to model time series with mixture components and exogenous variables. The parameters are estimated by quasi‐likelihood estimating equations. A modified EM algorithm is developed for the mixture time series model. The model and proposed algorithm are tested on simulated data and applied to mosquito surveillance data in Peel Region, Canada.
A sensitive quantitative assay for the determination of propafenone and two metabolites, 5‐hydroxypropafenone and N‐depropylpropafenone, in human K2EDTA plasma using LC–MS/MS with ESI operated in positive mode
Authors: Patel Harilal , Ghoghari Ashok , Bhatt Chandrakant , Shah Shaival , Jha Anilkumar , Desai Nirmal , Srinivas Nuggehally R.
Published: March 2017

Propafenone is a potent antiarrhythmic agent; clinically propafenone has been used for a number of cardiac arrhythmias because it possesses multiple modes of action, via beta adrenergic receptor blockade and calcium antagonistic activity. Propafenone (PPF) exhibits extensive saturable presystemic biotransformation (first‐pass effect) resulting in two active metabolites: 5‐hydroxypropafenone (5‐OH PPF) formed by CYP2D6 and N‐depropylpropafenone (NDP) formed by both CYP3A4 and CYP1A2 enzymes. A specific and sensitive LC–MS/MS method was developed and validated for quantitation of PPF, 5‐OH PPF and NDP using turboion spray in a positive ion mode. A solid‐phase extraction was employed for the extraction from human plasma. Chromatographic separation of analytes was achieved using an ACE‐5 C8 (50 × 4.6 mm) column with a gradient mobile phase comprising ammonium acetate containing 0.01% TFA in purified water and acetonitrile. The retention times achieved were 1.36, 1.23, 1.24 min and 1.34 min for PPF, 5‐OH PPF, NDP and IS (carbamazepine), respectively. Quantitation was performed by monitoring multiple reaction monitoring transition pairs of m/z 342.30 to m/z 116.20, m/z 358.30 to m/z 116.20, m/z 300.30 to m/z 74.20 and m/z 237.20 to m/z 194.10, respectively. The developed method was validated for various parameters. The calibration curves of PPF and 5‐OH PPF showed linearity from 1 to 500 ng/mL, with a lower limit of quantitation of 1.0 ng/mL and for NDP linearity from 0.1 to 25 ng/mL with a lower limit of quantitation of 0.1 ng/mL. The bias and precision for intra‐ and‐inter batch assays were <10 and 5%, respectively. The developed assay was used to evaluate pharmacokinetic properties of propafenone and its major metabolites in healthy human subjects.
Workshop: Theory Development Within the Information Sciences
Authors: Chu Sam , Sonnenwald Diane H. , Wu Mei‐Mei , Chang ShanJu Lin
Published: March 2017

EDITOR'S SUMMARY

The Theory Development within the Information Sciences workshop was held on October 15, 2016, at the ASIS&T Annual Meeting in Copenhagen, Denmark. The two main goals of the theory development workshop were to understand stages of theory development and discuss solutions to common challenges in the field, and to gauge the interests of the participants on theory development strategies. Diane Sonnenwald gave an overview on theory development based on her own experiences, Sam Chu talked about theory development applied to inquiry project‐based learning, Mei‐Mei Wu discussed multi methodologies in information retrieval and ShanJu Lin Chang touched on theory development processes in research on browsing phenomena. The workshop's second half was a roundtable discussion that involved participants discussing challenges in the field and receiving feedback from the presenters.
Research in Information Science Award: Everyday Life Information Seeking
Authors: Savolainen Reijo
Published: March 2017

EDITOR'S SUMMARY

Reijo Savolainen, 2016 recipient of the ASIS&T Research in Information Science Award, observes that research on information behavior tends to be skewed more heavily toward the context of the workplace, but focusing on everyday life information seeking (ELIS) brings information behavior into the sphere of ordinary life. Using Brenda Dervin's sense‐making methodology, research on ELIS can illuminate information seeking behavior for individuals in many different fields and circles. Qualitative study results from environmental activists, home buyers and unemployed individuals reveal how these groups seek information to help solve everyday problems. These studies highlight the use of information source horizons and preferred information seeking paths of individuals, showing patterns in how far people search for information and where they prefer to begin and end their searches. While social media provided useful information in these contexts, the information was often clouded behind affective factors when dealing with sensitive or controversial topics and thus were not always reliable or accessible to all.
Designing a Metaphor for Your Model
Authors: Creekmore Laura
Published: March 2017

EDITOR'S SUMMARY

Creating metaphors to explain a data model is vital to explain the model to people without the knowledge or experience to understand it quickly. Much like family trees evoke a sense of relationships between people by using the structure and design of a tree, strong metaphors for information architecture can help anyone understand the relationships in any data model. Good metaphors, such as web “pages,” stick with people, even if they are not completely accurate. New ways of expressing relationships in data demand new metaphors in order to express the necessity of data models to executives deciding whether or not to fund a project or even programmers that need to build around the model. Complex metaphors such as oceans, with ecosystems of fish and other organisms reacting to their environment, are far more accurate and fluid for explaining modern information architecture.
Inhibitors of Protein Tyrosine Phosphatase 1B from Marine Natural Products
Authors: Zhou Yue , Zhang Weirui , Liu Xiaoyu , Yu Haobing , Lu Xiaoling , Jiao Binghua
Published: March 2017

The ocean is a capacious area with the most abundant biological resources on the earth. The particularity of the marine ecological environment (high pressure, high salt, and hypoxia) makes the marine species survival competition fiercely, forcing many marine organisms in the process of life to produce a great deal of secondary metabolites with special structures and biological activities. In this article, 118 natural products which were isolated from four kinds of marine organisms, sponges, algae, soft corals and fungus, showing PTP1B inhibitory activity were summarized from 2010 to 2016, which may become the leading compounds towards treating Diabetes mellitus (DM). What's more, we briefly summarized the structure–activity relationship of PTP1B inhibitors.
Diversity Profile and Dynamics of Peptaibols Produced by Green Mould Trichoderma Species in Interactions with Their Hosts Agaricus bisporus and Pleurotus ostreatus
Authors: Marik Tamás , Urbán Péter , Tyagi Chetna , Szekeres András , Leitgeb Balázs , Vágvölgyi Máté , Manczinger László , Druzhinina Irina S. , Vágvölgyi Csaba , Kredics László
Published: March 2017

Certain Trichoderma species are causing serious losses in mushroom production worldwide. Trichoderma aggressivum and Trichoderma pleuroti are among the major causal agents of the green mould diseases affecting Agaricus bisporus and Pleurotus ostreatus, respectively. The genus Trichoderma is well‐known for the production of bioactive secondary metabolites, including peptaibols, which are short, linear peptides containing unusual amino acid residues and being synthesised via non‐ribosomal peptide synthetases (NRPSs). The aim of this study was to get more insight into the peptaibol production of T. aggressivum and T. pleuroti. HPLC/MS‐based methods revealed the production of peptaibols closely related to hypomurocins B by T. aggressivum, while tripleurins representing a new group of 18‐residue peptaibols were identified in T. pleuroti. Putative NRPS genes enabling the biosynthesis of the detected peptaibols could be found in the genomes of both Trichoderma species. In vitro experiments revealed that peptaibols are potential growth inhibitors of mushroom mycelia, and that the host mushrooms may have an influence on the peptaibol profiles of green mould agents.
Comparing Completion Agendas at Community Colleges and Global Counterparts
Authors: Raby Rosalind Latiner , Friedel Janice Nahra , Valeau Edward J.
Published: March 2017

This chapter compares the role of institutional and national completion agendas at community colleges and global counterparts around the world.
Community Colleges, Human Capital, and Economic Growth in Developing Countries
Authors: Tyndorf Darryl M. , Glass Chris R.
Published: March 2017

This chapter argues that increasing human capital through a combination of university and community college education promotes greater economic growth in developing countries.
Selectivity Effects in Bimetallic Catalysis: Role of the Metal Sites in the Decomposition of Formic Acid into H2 and CO2 by the Coinage Metal Binuclear Complexes [dppmMM′(H)]+
Authors: Zavras Athanasios , Krstić Marjan , Dugourd Philippe , Bonačić‐Koutecký Vlasta , O'Hair Richard A. J.
Published: March 2017

Design of new bimetallic catalysts requires an understanding of how cooperative effects of the metal sites influences reactivity. Here we show how switching one or both of the silver atoms in binuclear silver hydride cations, [dppmAg2(H)]+ (dppm=1,1‐Bis(diphenylphosphino)‐methane), with all combinations of copper and/or gold maintains selective dehydrogenation of formic acid, enhancing reactivity by up to 2 orders of magnitude. This is a key step in the selective, catalyzed extrusion of carbon dioxide from formic acid, HO2CH, with important applications in hydrogen storage and in situ generation of H2. Decarboxylation of [dppmMM′(O2CH)]+ through collision induced dissociation regenerates [dppmMM′(H)]+. DFT calculations provide insights into these cooperative effects. The copper homobinuclear catalyst performs best overall.
Examination of Selectivity in the Oxidation of ortho‐ and meta‐Disubstituted Benzenes by CYP102A1 (P450 Bm3) Variants
Authors: Munday Samuel D. , Dezvarei Shaghayegh , Lau Ian C.‐K. , Bell Stephen G.
Published: March 2017

Cytochrome P450 CYP102A1 (P450 Bm3) variants were used to investigate the products arising from the P450 catalysed oxidation of a range of disubstituted benzenes. The variants used all generated increased levels of metabolites compared to the wild‐type enzyme. With ortho‐halotoluenes up to six different metabolites could be identified whereas the oxidation of 2‐methoxytoluene generated only two aromatic oxidation products. Addition of an ethyl group markedly shifted the selectivity for oxidation to the more reactive benzylic position. Epoxidation of an alkene was also preferred to aromatic oxidation in 2‐methylstyrene. Significant minor products arising from the migration of one substituent to a different position on the benzene ring were formed during certain P450‐catalysed substrate turnovers. For example, 2‐bromo‐6‐methylphenol was formed from the turnover of 2‐bromotoluene and the dearomatisation product 6‐ethyl‐6‐methylcyclohex‐2,4‐dienone was generated from the oxidation of 2‐ethyltoluene. The RLYF/A330P variant altered the product distribution enabling the generation of certain metabolites in higher quantities. Using this variant produced 4‐methyl‐2‐ethylphenol from 3‐ethyltoluene with ≥90 % selectivity and with a biocatalytic activity suitable for scale‐up of the reaction.
Heterogeneous One‐Pot Carbonylation and Mizoroki–Heck Reaction in a Parallel Manner Following the Cleavage of Cinnamaldehyde Derivatives
Authors: Hattori Tomohiro , Ueda Shun , Takakura Ryoya , Sawama Yoshinari , Monguchi Yasunari , Sajiki Hironao
Published: March 2017

Carbon monoxide (CO) and styrene derivatives that can be both generated by a palladium on carbon (Pd/C)‐catalyzed carbon–carbon (C−C) bond cleavage reaction of cinnamaldehyde derivatives were effectively utilized in further palladium‐catalyzed C−C bond forming reactions in a direct and practical way. CO derived from simple and affordable CO carriers such as cinnamaldehyde or terephthalaldehyde was efficiently employed in the in situ CO fixation with various aromatic iodides through a palladium‐catalyzed carbonylation followed by an inter‐ or intramolecular coupling reaction with alcohols to afford the corresponding esters or lactones, respectively. Styrene derivatives were also efficient substrates in an in situ Mizoroki–Heck‐type cross‐coupling reaction with aryl iodides, leading to the effective formation of asymmetric stilbenes. The decarbonylation of cinnamaldehyde derivatives and the subsequent independent syntheses of both esters/lactones and 1,2‐diarylethenes could be achieved in a virtual one‐pot and in situ reaction using a H‐shaped pressure‐tight glass‐sealed tube consisting of two independent but laterally connected reaction tubes in the gas space.
Carboranes as Aryl Mimetics in Catalysis: A Highly Active Zwitterionic NHC‐Precatalyst
Authors: Selg Christoph , Neumann Wilma , Lönnecke Peter , Hey‐Hawkins Evamarie , Zeitler Kirsten
Published: March 2017

Modern catalysis takes advantage of aryl‐based interactions to tune and control reactions. In the design of N‐heterocyclic‐carbene catalysts, both the electronic and steric nature of the nitrogen substituents play a crucial role. Although hydrocarbon‐based systems and especially aryl residues have contributed considerably to overcome multifaceted catalytic challenges, the unique properties of carborane moieties, including delocalized charge, potential planar chirality, and well‐known thermodynamic stability, offer unprecedented opportunities to develop new catalysts while being employed as aryl mimetics. We report a straightforward synthetic route to a novel zwitterionic triazolium‐based N‐heterocyclic carbene (NHC) precatalyst bearing a 7,8‐dicarba‐nido‐undecaboranyl substituent. The catalyst's excellent activity and its broad applicability are demonstrated in a wide range of organocatalytic transformations. Comparison of the performance with known N‐aryl NHC catalysts offers preliminary insights into the stereoelectronic nature of this nido‐carboranyl substituent.
Methoxylation and Direct Hydrogenative Coupling of Chloronitrobenzenes in Continuous Flow
Authors: Shi Songjie , Wan Li , Sun Xiaoning , Zhang Jiawei , Guo Kai
Published: March 2017

A novel continuous flow method for the methoxylation of chloronitrobenzenes was developed. The reaction went smoothly and high yields were achieved under the optimized conditions. Furthermore, up to 76% yield of azoxybenzenes were obtained from the corresponding nitrobenzenes in the presence of NaOH in continuous flow. Compared to batch conditions, the reaction time was significantly shortened, and the chemical waste was reduced obviously.
Recent Progress on Transition Metal (Fe, Co, Ni, Ti and V) Complex Catalysts in Olefin Polymerization with High Thermal Stability
Authors: Ma Zhifeng , Yang Wenhong , Sun Wen‐Hua
Published: March 2017

The design and synthesis of transition metal complexes with high thermal stability in olefin polymerization have become more and more important in order to meet the need of industrial application. This review focuses on the transition metal complex catalyst with high thermal stability containing different structures, including the backbone of bis(imino)pyridine, α‐diimine and other types of ligands. Besides the catalytic activity, the influence of reaction temperature on the molecular weight and molecular weight distribution of the obtained polymer was also described. The plausible mechanism on the stability of catalysts at high temperature was proposed, which may give guidance to design catalyst with good thermal stability.
Recent Advances in Oxidative ipso‐Annulation of N‐Arylpropiolamides
Authors: Song Renjie , Xie Yexiang
Published: March 2017

Oxidative radical reactions have attracted much attention due to their extensive applications in organic synthesis. We herein summarize recent progress in the oxidative ipso‐annulation of N‐arylpropiolamides with various functional reagents, including ethers, alkanes, aldehydes, NaSO2CF3, tert‐butyl nitrite, disulfides, thiophenols, sulfonylhydrazides, AgSCF3, tetra‐n‐butyl ammonium bromide (TBAB), phosphorus and silanes, for the construction of diverse substituted spirocycles. Moreover, the mechanisms for the oxidative ipso‐annulation of N‐arylpropiolamides were also discussed.
Post‐selection inference for ‐penalized likelihood models
Authors: Taylor Jonathan , Tibshirani Robert
Published: March 2017

We present a new method for post‐selection inference for (lasso)'penalized likelihood models, including generalized regression models. Our approach generalizes the post‐selection framework presented in Lee et al. (2013). The method provides P‐values and confidence intervals that are asymptotically valid, conditional on the inherent selection done by the lasso. We present applications of this work to (regularized) logistic regression, Cox's proportional hazards model, and the graphical lasso. We do not provide rigorous proofs here of the claimed results, but rather conceptual and theoretical sketches. The Canadian Journal of Statistics 46: 41–61; 2018 © 2017 Statistical Society of Canada
Semiparametric estimation for measurement error models with validation data
Authors: Xu Yuhang , Kim Jae Kwang , Li Yehua
Published: March 2017

We consider regression problems where error‐prone surrogates of true predictors are collected in a primary data set while accurate measurements of the predictors are available only in a relatively small validation data set. We propose a new class of semiparametric estimators for the regression coefficients based on expected estimating equations, where the relationship between the surrogates and the true predictors is modelled nonparametrically using a kernel smoother trained with the validation data. The new methods are developed under two different scenarios where the response variable is either observed or not observed in the validation data set. The proposed estimators have a natural connection with the fractional imputation method. They are consistent, asymptotically unbiased, and normal in both scenarios. Our simulation studies show that the proposed estimators are superior to competitors in terms of bias and mean squared error and are quite robust against the misspecification of the regression model and bandwidth selection. A real data application to the Korean Longitudinal Study of Aging is presented for illustration.The Canadian Journal of Statistics45: 185–201; 2017 © 2017 Statistical Society of Canada
Pharmacokinetic Considerations for Combining Antiretroviral Therapy, Direct‐Acting Antiviral Agents for Hepatitis C Virus, and Addiction Treatment Medications
Authors: Bednasz Cindy J. , Venuto Charles S. , Ma Qing , Morse Gene D.
Published: March 2017

There are many factors that can affect the pharmacokinetics (PK) of drugs. Pathophysiological changes from disease states can alter the mechanisms that control the PK of antiretrovirals (ARVs), direct‐acting antivirals (DAAs), and addiction treatment medications. Drug–drug interaction pathways of certain ARVs and DAAs can be very complex, with agents being substrates, inhibitors, or inducers of multiple metabolic and transporter pathways. Buprenorphine and methadone may be used in HIV‐ and hepatitis C virus (HCV)–infected patients and may also be affected by drug interactions. Current research is focused on novel PK analyses, which aim to describe the PK of agents within organs that host the infection of interest, such as within hepatocytes during treatment for HCV. Modeling techniques allow for the prediction of drug PK in specific organs and the plasma compartment. This review will provide a summary of these areas while exploring PK considerations for ARVs, DAAs, and addiction treatment medications.
Asunaprevir: An HCV Protease Inhibitor With Preferential Liver Distribution
Authors: Eley Timothy , Garimella Tushar , Li Wenying , Bertz Richard J.
Published: March 2017

Asunaprevir is an inhibitor of the hepatitis C virus (HCV) NS3/4A protease, demonstrating efficacy in clinical studies in patients infected with HCV genotype 1 or 4, with either peginterferon/ribavirin or combinations of direct‐acting antivirals. Because of preferential distribution of asunaprevir to the liver via organic anion‐transporting polypeptide (OATP)–mediated transport, asunaprevir demonstrates high apparent oral clearance and very low plasma concentrations. Asunaprevir plasma concentrations are markedly increased by single‐dose rifampin (an OATP inhibitor) and in subjects with moderate to severe hepatic impairment. In addition, modestly higher plasma concentrations of asunaprevir have been noted in subjects infected with HCV relative to healthy subjects and in Asian subjects relative to whites. At the marketed dose, infrequent hepatic transaminase abnormalities were poorly predicted by plasma concentrations. For a compound with these characteristics, hepatic concentrations may have provided an improved understanding of the in vivo pharmacokinetic and pharmacodynamic data to support decision making during development.
Cure Strategies for Hepatitis B Virus: The Promise of Immunotherapy
Authors: Shire Norah J.
Published: March 2017

Chronic hepatitits B virus remains a public health challenge, infecting more than 240 million people globally and causing 600,000 deaths per year from end‐stage liver disease and/or hepatocellular carcinoma. Current antiviral therapeutic agents are highly effective at blocking viral replication, but discontinuation of therapy prior to loss of hepatitis B surface antigen generally leads to relapse. New modalities that target host factors of viral persistence such as immune response pathway inhibition hold promise. Other experimental approaches may target virally related persistence factors, including covalently closed circular DNA. All these approaches will require creative new means of assessing proof of biology and proof of mechanism, particularly in the relevant compartment of liver tissue. Furthermore, it is likely to require combinations of modalities in defined patient populations to achieve optimal response. A precompetitive consortium approach may enable companies, regulators, and academic researchers to share best practices and evaluate preclinical and clinical pathways for these novel approaches.
Assessment of Hepatic Impairment and Implications for Pharmacokinetics of Substance Use Treatment
Authors: Talal Andrew H. , Venuto Charles S. , Younis Islam
Published: March 2017

Although the liver is the primary site of metabolism and biliary excretion for many medications, data are limited on the liver's pharmacokinetic abilities in cirrhosis. Cirrhosis develops through collagen deposition, eventually culminating in end‐stage liver disease that compromises hepatic drug metabolism. Consequently, the US Food and Drug Administration (FDA) recommends evaluating the pharmacokinetics of medications in subjects with hepatic impairment if hepatic metabolism constitutes more than 20% of their elimination or if they have a narrow therapeutic range. A variety of noninvasive indices and radiologic procedures can be employed to assess hepatic drug metabolism and excretion. The Child‐Pugh score is the most commonly used scale for assessing hepatic impairment among drugs submitted for US FDA approval. The score, originally developed to guide operative mortality in patients undergoing hepatic resection, has not been modified since its inception 5 decades ago. Furthermore, the score was not originally intended to be a guide for potential dose modification in patients with hepatic impairment. These reasons, in combination with the availability of a variety of new imaging modalities and an enhanced understanding of hepatic biology, should foster the development of novel methods to assess the effect of hepatic impairment on liver drug metabolism.
Bicyclo[6.3.0]undeca‐1(11),2,4,6,8‐pentaen‐10‐ylidene: An Aromatic Carbene with Ambiphilic Properties
Authors: Ishikawa Hiroyuki , Nishida Jun‐ichi , Jones John W. , Scott Lawrence T. , Kawase Takeshi
Published: March 2017

The title carbene (4) was generated as a highly reactive species in solution by photoirradiation of 10‐diazobicyclo[6.3.0]undecapentaene (5) using a high‐pressure mercury lamp. Carbene 4 reacts with benzene to afford two isomeric adducts, 10‐phenylbicyclo[6.3.0]undecapentaene (10) and tricyclo[9.3.03, 10.0]heptadeca‐1,3(10),4,6,8,12,14,16‐octaene (11). The reactivity toward benzene is a characteristic of an electrophilic aromatic carbene analogous to cyclopentadienylidene 1. In contrast, the reaction of 4 with methanol produces 7‐methoxybicyclo[6.3.0]undeca‐1,3,5,8,10‐pentaene (15). When [D1]methanol was employed as a reactant, the 10‐deuterated analogue was formed. The results clearly indicate the formation of bicyclo[6.3.0]undecapentaenyl cation (7) as a novel 10 π‐electronic compound by protonation of 4. Theoretical calculations indicate that the 2‐ and 7‐positions of the cation have the largest positive charge in the cation. Moreover, the carbene was generated in the presence of tert‐butyl hydroperoxide in aqueous tetrahydrofuran to afford azulene through oxidation of 7, followed by decarbonylation. The nucleophilic property of carbene 3 is similar to that of cycloheptatrienylidene 2. Thus, 4 can be regarded as a novel ambiphilic aromatic carbene.
Systematic Investigation of Resorcin[4]arene‐Based Cavitands as Affinity Materials on Quartz Crystal Microbalances
Authors: Ryvlin Dimitrij , Dumele Oliver , Linke Alexander , Fankhauser Daniel , Schweizer W. Bernd , Diederich François , Waldvogel Siegfried R.
Published: March 2017

Resorcin[4]arene cavitands are well‐known supramolecular hosts, and their outstanding guest‐binding abilities in solution have been studied in detail in recent decades. In a systematic approach, different resorcin[4]arene cavitands and container molecules are characterized as affinity materials for gravimetric sensing using high‐fundamental‐frequency quartz crystal microbalances. Analysis of their affinity toward a series of various analytes reveals a remarkable dependence of both selectivity and sensitivity on the shape, accessibility, and size of the cavity, along with their supramolecular interactions with the host molecules.
What Drives Successful Implementation of Product Stewardship Strategy? The Role of Absorptive Capability
Authors: Bhupendra Kumar Verma , Sangle Shirish
Published: March 2017

Implementation of Product Stewardship Strategy (PSS) requires integration of ‘voices of stakeholders’ in business decisions to create ‘differentiation’ in the market place. Considering that absorptive capability (AC) is a critical aspect of organizational learning, it may deliver dynamic integration of stakeholder's expectations and know‐how in decision making. This paper attempts to link the attributes of AC with the features of PSS and presents outcomes of an empirical study of sixty Indian firms from several industry sectors. The result shows that firms demonstrating the traits of AC are in better position to implement PSS. This study also expands the scope of AC by including the additional source of knowledge as societal‐stakeholders to provide a comprehensive view that this type of knowledge is complimentary to technological and market knowledge for sustainable commercial success. Based on the research findings, the paper proposes some important managerial implications and suggests direction for future research. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
Corporate Social Responsibility Reporting and Varieties of Capitalism: an International Analysis of State‐Led and Liberal Market Economies
Authors: Gallego‐Álvarez Isabel , Quina‐Custodio Ivo Alexandre
Published: March 2017

Different studies carried out to date in the corporate social responsibility (CSR) field have focused on analysing certain explanatory factors of CSR reporting in different countries or individual factors, such as firm size, activity sector, good corporate governance, economic and financial profitability, and the cost of equity capital, among others. In contrast, other aspects of national cultures and institutions that make up the macroeconomic, legal, and political context of a country have been addressed to a lesser extent. This paper analyses how aspects of national institutions affect CSR reporting on an international level using the varieties of the capitalism approach. This approach is concerned with companies and the ways in which they interact strategically to solve the coordination problems that arise from their activities. The study uses data from the Thomson Reuters Eikon database and the Global Reporting Initiative (G3.1) for a sample of firms from countries classified as state‐led market economies (France, Portugal, and Spain) and countries considered liberal market economies (the USA and the UK). The results obtained by linear regression show those companies in state‐led market economies disclose more concerning CSR than companies in liberal market economies. Moreover, firms in state‐led market economies disclose more on stakeholder aspects such as social, environmental and business behaviour than companies in liberal market economies. This may be due to coercive pressure, that is, the existence of a significant and well‐developed legal system that seeks to protect stakeholders and is not exclusively oriented towards shareholder interests. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
Effects of ultrasound irradiation on enzymatic hydrolysis of protein and application for the determination of tetracyclines in complex matrices
Authors: Zhou Qian , Wang Hong , Zhu Kuanzheng , Zhu Lihua , Zhou Shengyin , Peng Jin , Lu Xiya
Published: March 2017

The widespread use of tetracyclines (TCs) in food animals has led to concerns regarding unsafe residue levels in feed, food and manure. The determination of TCs in such matrices suffers from interference by the interactions between proteins and TCs. Three deproteination methods were compared in this study. In contrast with acid deproteination, which caused a large loss of TCs due to the strong adsorption of TCs on protein precipitates, a normal enzymatic hydrolysis was confirmed to have a merit of effectively releasing TCs from protein matrices, but required treatment time as long as 16 h. The adoption of ultrasound irradiation was proposed to shorten the enzymatic hydrolysis time. After investigating the effects of ultrasound power and irradiation time, the conditions of the ultrasound‐enhanced enzymatic hydrolysis were optimized as ultrasound power of 100 W and irradiation time of 6 min. The ultrasound‐enhanced enzymatic hydrolysis treatment of 6 min yielded recovery of TCs (from protein‐containing matrices) as high as that obtained by the normal enzymatic hydrolysis treatment of 16 h. The acceleration effect of ultrasound irradiation was attributed to ultrasound‐induced cavitation, which increased exposure of both the functional groups of trypsin and the C‐terminal amino acid in the protein that was a cleavage site for trypsin attack. When the ultrasound‐enhanced enzymatic hydrolysis method was used to determine TCs in complex matrices, it was found that this new method achieved recoveries of 89.5, 117.7, 110.4 and 100.0% for oxytetracycline, tetracycline, chlortetracycline and doxycycline, being much higher than those (29.6–39.4%) obtained using the common acid deproteination process. Copyright © 2017 John Wiley & Sons, Ltd.