bluuebunny/crossref_metadata_2025 huggingface dataset:
Synaptic Structure Quantification in Cultured Neurons
Authors: Roqué Pamela J. , Guizzetti Marina , Costa Lucio G.
Published: May 2014

Behavioral problems (e.g., learning and memory) following developmental exposure to toxicants suggests that dysregulation of the process of synapse formation and function may occur. The ability to assess these changes is thus of value. This unit describes a method to investigate toxicant‐induced changes to synaptic structure formation in primary hippocampal neurons using immunocytochemical labeling of the pre‐ and post‐synaptic markers synaptophysin and PSD‐95, confocal imaging, and three‐dimensional object analysis. Protocols for the long‐term culturing of primary hippocampal neurons and of primary cortical astrocytes, as well as their co‐culture, are included. While the described methods focus on how astrocytes influence synapse formation and how toxicants may interfere in this process, modifications to the experimental plan can easily be implemented. This would allow for the investigation of the effects of toxicants after treating neurons alone, or both astrocytes and neurons in co‐culture. With the common endpoint of synapse structure formation, differences between varying treatment paradigms can expand the understanding of the influence of particular toxicants on these diverse cell types and provide insight into potential mechanisms of effect and the contributions of each to synapse formation. Curr. Protoc. Toxicol. 60:12.22.1‐12.22.32. © 2014 by John Wiley & Sons, Inc.
Magnetopause reconnection and energy conversion as influenced by the dipole tilt and the IMF Bx
Authors: Hoilijoki Sanni , Souza Vitor M. , Walsh Brian M. , Janhunen Pekka , Palmroth Minna
Published: May 2014

We study the effect of Earth's dipole tilt angle and interplanetary magnetic field (IMF) Bx and By components on the location of reconnection and the energy conversion at the magnetopause. We simulate southward IMF satisfying both inward‐ and outward‐type Parker spiral conditions during three different dipole tilt angles using a global magnetohydrodynamic model GUMICS‐4. We find that positive (negative) Bx contributes to the magnetopause reconnection line location by moving northward (southward) and positive (negative) dipole tilt angle by moving it southward (northward). The tilt shifts the dayside load region toward the winter hemisphere and the summer cusp toward the equatorial plane. Magnetic flux hence piles effectively in the summer hemisphere leading to increased magnetopause currents that enhance the Poynting flux through the magnetopause. We find that the intensity of the energy conversion in the generators is strongly affected by the dipole tilt angle, whereas intensity in the load region is mainly affected by IMF Bx.
The long‐wavelength admittance and effective elastic thickness of the Canadian Shield
Authors: Kirby J. F. , Swain C. J.
Published: May 2014

The strength of the cratonic lithosphere has been controversial. On the one hand, many estimates of effective elastic thickness (Te) greatly exceed the crustal thickness, but on the other the great majority of cratonic earthquakes occur in the upper crust. This implies that the seismogenic thickness of cratons is much smaller than Te, whereas in the ocean basins they are approximately the same, leading to suspicions about the large Te estimates. One region where such estimates have been questioned is the Canadian Shield, where glacial isostatic adjustment (GIA) and mantle convection are thought to contribute to the long‐wavelength undulations of the topography and gravity. To date these have not been included in models used to estimate Te from topography and gravity which conventionally are based only on loading and flexure. Here we devise a theoretical expression for the free‐air (gravity/topography) admittance that includes the effects of GIA and convection as well as flexure and use it to estimate Te over the Canadian Shield. We use wavelet transforms for estimating the observed admittances, after showing that multitaper estimates, which have hitherto been popular for Te studies, have poor resolution at the long wavelengths where GIA and convection predominate, compared to wavelets. Our results suggest that Te over most of the shield exceeds 80 km, with a higher‐Te core near the southwest shore of Hudson Bay. This means that the lack of mantle earthquakes in this craton is simply due to its high strength compared to the applied stresses.
AGU Celebrates Leaders for Contributions to Policy and Public Awareness
Authors: Buhrman Joan
Published: May 2014

In recognition of outstanding leadership and vision in shaping policy and heightening public awareness of the value of Earth and space science, AGU has chosen Sen. Barbara Mikulski (D‐Md.), chairwoman of the Senate Appropriations Committee; Naomi Oreskes, a science historian and author of the book Merchants of Doubt; and Eugenie Scott, former executive director for the National Center for Science Education (NCSE), as recipients of the 2014 AGU Presidential Citations for Science and Society. The awards will be presented on Tuesday, 17 June, during the 2014 AGU Science Policy Conference at a reception on Capitol Hill.
Observing trends in total ozone and extreme ozone events
Authors: Balcerak Ernie
Published: May 2014

The ozone layer in the stratosphere has been recovering since the 1989 Montreal Protocol reduced the use of ozone‐destroying chlorofluorocarbons. Fitzka et al. observed trends in total ozone levels and the vertical distribution of ozone at Hoher Sonnblick, a mountain in Austria, from 1994 to 2011.
Snowmelt decreases in lower‐density forests
Authors: Wendel JoAnna
Published: May 2014

As climate change threatens global freshwater supplies, researchers are looking for better ways to manage water sources like snowmelt. Many regions of the world depend on annual snowmelt for water, and portions of these regions are also forested. Forest dynamics are complex and can vary widely depending on region, precipitation, altitude, and many other factors, which makes it difficult to determine whether dense forests retain snowpack or accelerate melt.
Trees, more than shrubs, protect against soil erosion
Authors: Wendel JoAnna
Published: May 2014

Soil erosion and saltation—the transport of ground particles by wind—are significant producers of dust and can damage crops or lead to nutrient‐poor soil in semiarid regions. These regions are particularly vulnerable to climate warming and increased human activity, which can exacerbate erosion and induce dust bowl–like conditions. Previous research and observations have shown that vegetation such as shrubs and trees can reduce soil erosion, but existing models do not account for variations in wind direction or strength.
Warm river waters contributed to melting Arctic sea ice
Authors: Balcerak Ernie
Published: May 2014

In 2012 Arctic sea ice extent reached a record low in the satellite‐observed record. A new study by Nghiem et al. suggests that warm waters discharged into the Arctic's Beaufort Sea from the Mackenzie River could have contributed to that low ice extent.
Antarctica's Whillans Ice Plain ice flows are highly variable
Authors: Schultz Colin
Published: May 2014

The Whillans Ice Plain (WIP) is a roughly 20,000‐square‐kilometer region of the West Antarctic Ice Sheet that acts as a massive conveyor, driving glacial ice into the Ross Ice Shelf. As the climate changes, knowing how large bodies of ice like the WIP behave will be important to assessing sea level rise.
Ultrasonic Welding of Bulk Carbon Nanotube Conductors
Authors: Schauerman Christopher M. , Alvarenga Jack , Staub Jason , Forney Michael W. , Foringer Ryan , Landi Brian J.
Published: May 2014

Incorporation of bulk carbon nanotube (CNT) conductors into energy and data systems can require new methods of making a functional interface with low electrical contact resistance and high mechanical strength. Ultrasonic welding has been shown as a viable technique for mechanically and electrically bonding commercial CNT materials (CVD) to copper foil. The mechanical strength across the ultrasonic welds was measured via dynamic mechanical analysis with single lap welds exceeding 350 kPa. The electrical properties of the ultrasonically welded bulk CNT conductors (chemically doped with KAuBr4) to Cu were measured via 4‐point probe and show specific contact resistance between the CNTs and copper as low as 4.3 mΩ cm2. Thus, ultrasonic welding represents a mechanically robust method for making functional contacts between bulk CNTs and metallic interconnects with a low contact resistance. In addition, ultrasonic welding was successfully used to join two CNT ribbons end‐to‐end (breaking strength of single lap welds exceeding 200 kPa) demonstrating that it is also a viable technique for making larger dimension CNT materials from smaller components.
Micromolding Surface‐Initiated Polymerization: A Versatile Route for Fabrication of Coatings with Microscale Surface Features of Tunable Height
Authors: Escobar Carlos A. , Cooksey Tyler J. , Spellings Matthew P. , Jennings G. Kane
Published: May 2014

This article introduces a process termed micromolding surface‐initiated polymerization (μMSIP) as a versatile route to provide surface‐bound, partially fluorinated polymer coatings with a homogeneous array of microscale surface features. The process employs hard‐polydimethylsiloxane (h‐PDMS) to mold the surface structure of master substrates exhibiting patterned microscale features. Upon filling the mold with the monomer 5‐(perfluorooctyl)norbornene (NBF8) and placing against a surface that is pre‐activated for surface‐initiated ring‐opening metathesis polymerization (SI‐ROMP), a partially fluorinated polymer film propagates from the surface with features that grow into the recesses of the mold to produce the final microtextured coating. The heights of these features can be tuned from 20–100% of the full height of the mold features based on the amount of initiator employed as well as the polymerization time and temperature. Reproduced topographies include pyramidal and inverted pyramidal structures. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) images show that the final polymer film exhibits a homogeneously microstructured surface that resembles that of its corresponding master.
Exploring the indirect effects of catechol‐O‐methyltransferase (COMT) genotype on psychotic experiences through cognitive function and anxiety disorders in a large birth cohort of children
Authors: Niarchou Maria , Zammit Stanley , Escott‐Price Valentina , Owen Michael J. , van den Bree Marianne B. M.
Published: May 2014

Children reporting psychotic experiences (PEs) are at increased risk of developing psychosis in adulthood. Cognitive deficits and anxiety disorders often precede psychotic disorders and are associated with higher risk of PEs. While the high activity alleles of variants within COMT have been associated with cognitive deficits, and the low activity alleles with higher risk of anxiety disorders, no associations of COMT with PEs have been found. One possible explanation is that the association between COMT and PEs is indirect, through cognitive function and anxiety disorders. We examined whether the association between PEs and COMT (four single nucleotide polymorphisms and three haplotypes) is indirect, through cognition or anxiety disorders. 6,784 individuals from the Avon Longitudinal Study of Parents and Children (ALSPAC) were genotyped and completed neurocognitive assessments at ages 8 and 11, as well as semi‐structured interviews for anxiety disorders and PEs at ages 10 and 12, respectively. Alleles rs2097603 and rs4680, and two COMT haplotypes, all indexing high activity, were indirectly associated with higher risk of PEs through impaired processing speed, IQ and attention. There was no evidence of a total effect of COMT on PEs, nor for an indirect effect through anxiety disorders. This is the first study to examine indirect effects of COMT on PEs. Evidence of an indirect association suggests a complex developmental pathway underlies the emergence of PEs in children, with possible implications for prevention/intervention strategies. Our findings provide additional support for processing speed and attention as endophenotypes in psychotic disorders. © 2014 Wiley Periodicals, Inc.
Carbonylierungen von Alkenen mit CO‐Alternativen
Authors: Wu Lipeng , Liu Qiang , Jackstell Ralf , Beller Matthias
Published: May 2014

Alkencarbonylierungen sind wichtige Prozesse für die Produktion von Groß‐ und Feinchemikalien. Heutzutage nutzen alle industriellen Carbonylierungsprozesse das hochtoxische und brennbare Gas Kohlenmonoxid, dessen Eigenschaften einen breiten Einsatz von Carbonylierungen in Industrie und Wissenschaft aber erschweren. Daher ist die Durchführung von Carbonylierungen ohne Verwendung von CO wünschenswert, auch unter den Gesichtspunkten der nachhaltigen Chemie. Obwohl über Alternativen zu Kohlenmonoxid schon seit 30 Jahren berichtet wurde, erweckte dieses Gebiet erst vor kurzem wieder ein größeres Interesse. Dieser Kurzaufsatz fasst Carbonylierungen von Alkenen mit unterschiedlichen Kohlenmonoxidalternativen zusammen.
A Metallic Room‐Temperature Oxide Ion Conductor
Authors: Heise Martin , Rasche Bertold , Isaeva Anna , Baranov Alexey I. , Ruck Michael , Schäfer Konrad , Pöttgen Rainer , Eufinger Jens‐Peter , Janek Jürgen
Published: May 2014

Nanoparticles of Bi3Ir, obtained from a microwave‐assisted polyol process, activate molecular oxygen from air at room temperature and reversibly intercalate it as oxide ions. The closely related structures of Bi3Ir and Bi3IrOx (x≤2) were investigated by X‐ray diffraction, electron microscopy, and quantum‐chemical modeling. In the topochemically formed metallic suboxide, the intermetallic building units are fully preserved. Time‐ and temperature‐dependent monitoring of the oxygen uptake in an oxygen‐filled chamber shows that the activation energy for oxide diffusion (84 meV) is one order of magnitude smaller than that in any known material. Bi3IrOx is the first metallic oxide ion conductor and also the first that operates at room temperature.
Remote‐controlled peristaltic locomotion in free‐floating pnipam hydrogels
Authors: Gregory Jarod , Riasi M. Sadegh , Cannell Jonathan , Arora Hitesh , Yeghiazarian Lilit , Nistor Vasile
Published: May 2014

Peristalsis‐driven locomotion, by nature of its flexibility and deformability, is a highly advantageous mechanism for mobility in soft materials and robots; however, utilization of this mechanism has been limited to restricted, frictional environments. (Seok et al., presented at 2010 IEEE International Conference on Robotics and Automation, Anchorage, AK May 3–8, 2010; Boxerbaum et al., Int J Robotics Res 2012, 31, 302; Boxerbaum et al., presented at 2011 IEEE/RSJ International Conference on Intelligent Robots and Systems, San Francisco, CA, 2011; Arora et al., J Polym Sci Part A: Polym Chem 2009, 47, 5027). We have removed this limitation and expanded the use of peristaltic locomotion to open aqueous environments by remotely inducing peristalsis via spatially controlled volume phase transitions in thermosensitive poly(N‐isopropylacrylamide) (PNIPAM) hydrogels. The resulting asymmetry causes steady, incremental linear displacement in the hydrogel's center of mass, thus producing directed, remote‐controlled locomotion. In our proof‐of‐principle system, we controlled the peristaltic locomotion of the hydrogels using a handheld laser to selectively induce volume phase transitions in the hydrogel. The PNIPAM hydrogels' energy absorbance capability was enhanced by incorporating the New Indocyanine Green laser dye (IR‐820) into the gel. The use of IR‐820 is likely to expand the application space for these hydrogels due to new opportunities for conjugation chemistry. (Prajapati et al., Molecular Imaging 2009, 8, 45; Fernandez‐Fernandez et al., Molecular Imaging 2011, 11, 1). Overall, such an approach increases the capability of both peristaltic locomotion as a mechanism for mobility in soft robots, and PNIPAM hydrogels as a biotechnological platform. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40927.
Enhanced microwave absorbing properties of lightweight films based on polyaniline/aliphatic polyurethane composites in X band
Authors: Zeghina Sofiane , Wojkiewicz Jean‐Luc , Lamouri Saad , Belaabed Belkacem , Redon Nathalie
Published: May 2014

Polymer blends based on nanostructured polyaniline (PANI) doped with hydrochloric acid (HCl) and para‐toluene sulfonic acid (PTSA) introduced into aliphatic polyurethane matrix (PU) are synthesized to produce flexible thin composite films for microwave absorbers. The effects of dopant type, PANI content and film thickness on morphologies, dielectric and microwave absorption properties in the X‐band are studied. It reveals that real and imaginary parts of the complex permittivity are proportional to filler concentrations and type of doped PANI. The PANI‐PTSA/PU films show higher permittivity and better microwave absorbing properties than PANI‐HCl/PU for the same weight fraction of PANI. The minimum reflection loss RL(dB) values for the PANI‐PTSA/PU are −37 dB at (20% PANI and 11.6 GHz) and −30 dB at (15% PANI and 11.3 GHz) for thicknesses of 1.2 and 1.6 mm, respectively. These high values of reflection losses make the obtained lightweight and flexible composites promising radar absorbing materials (RAM). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40961.
Quality of life after surgical resection compared with radiofrequency ablation for small hepatocellular carcinomas
Authors: Huang G , Chen X , Lau W Y , Shen F , Wang R-Y , Yuan S-X , Geng W-X , Zhou W-P
Published: May 2014

Background

Health-related quality of life (HRQL) is an important outcome measure in studies of cancer therapy. This study aimed to investigate HRQL and survival in patients with small hepatocellular carcinoma (HCC) treated with either surgical resection or percutaneous radiofrequency ablation (RFA).

Methods

Between January 2006 and June 2009, patients with newly diagnosed solitary, small (3 cm or less) HCC were invited to participate in this non-randomized prospective parallel cohort study. The Functional Assessment of Cancer Therapy – Hepatobiliary (FACT-Hep) instrument was used for assessing HRQL. HRQL and survival were compared between the two treatment groups.

Results

A total of 389 patients were enrolled. Questionnaires were completed fully by 99·7 per cent of invited participants (388 of 389) at baseline, 98·7 per cent (383 of 388) at 3 months, 99·0 per cent (379 of 383) at 6 months, 98·4 per cent (365 of 371) at 1 year, 96·6 per cent (336 of 348) at 2 years and 95·1 per cent (289 of 304) at 3 years. There were no significant differences in disease-free and overall survival between the two groups. Patients treated with percutaneous RFA had significantly better HRQL total scores after 3, 6, 12, 24 and 36 months than those who had surgical resection (P < 0·001, P < 0·001, P = 0·001, P = 0·003 and P = 0·025 respectively). On multivariable analysis, the presence of concomitant disease, cirrhosis and surgical resection were significant risk factors associated with a worse HRQL score after treatment.

Conclusion

Percutaneous RFA produced better post-treatment HRQL than surgical resection for patients with solitary small (no more than 3 cm) HCC.
Optimization of a validated stability‐indicating RP‐LC method for the determination of fulvestrant from polymeric based nanoparticle systems, drugs and biological samples
Authors: Gumustas Mehmet , Sengel‐Turk Ceyda Tuba , Hascicek Canan , Ozkan Sibel A.
Published: May 2014

Fulvestrant is used for the treatment of hormone receptor‐positive metastatic breast cancer in postmenopausal women with disease progression following anti‐estrogen therapy. Several reversed‐phase columns with variable silica materials, diameters, lengths, etc., were tested for the optimization study. A good chromatographic separation was achieved using a Waters X‐Terra RP18 column (250 × 4.6 mm i.d. × 5 µm) and a mobile phase, consisting of a mixture of acetonitrile–water (65:35; v/v) containing phosphoric acid (0.1%). The separation was carried out 40°C with detection at 215 nm.The calibration curves were linear over the concentration range between 1.0–300 and 1.0–200 µg/mL for standard solutions and biological media, respectively. The proposed method is accurate and reproducible. Forced degradation studies were also realized. This fully validated method allows the direct determination of fulvestrant in dosage form and biological samples. The average recovery of the added fulvestrant amount in the samples was between 98.22 and104.03%. The proposed method was also applied for the determination of fulvestrant from the polymeric‐based nanoparticle systems. No interference from using polymers and other excipients was observed in in vitro drug release studies. Therefore an incorporation efficiency of fulvestrant‐loaded nanoparticle could be determined accurately and specifically. Copyright © 2014 John Wiley & Sons, Ltd.
Gradient elution mode for the troubleshooting of matrix effect on the determination of G004 in different tissues by LC‐MS/MS
Authors: Hu Linlin , Agbokponto Janvier Engelbert , Ding Li , Liu Bing , Shi Fuguo , Gong Chuting
Published: May 2014

A steep gradient elution mode was applied to reduce the risk of matrix effect (ME) for the determination of G004, a novel sulfonylurea hypoglycemic drug, in a tissue distribution study by LC‐MS/MS. The mass spectra of the total‐ion‐current chromatograms combined with the post‐column infusion traces enabled the ‘unseen’ interfering species to be directly detected, and ensured that the chromatography conditions and sample preparation method were adequate to overcome the ME. According to this, a steep gradient elution mode was designed to overcome the intense ME from different tissues. The analysis was performed by monitoring the transitions m/z 558.1 → 419.0 for G004 and m/z 489.3 → 364.1 for glimepiride used as the internal standard. Calibration curves recovered over a range from 0.1 to 10000 ng/mL for seven different tissues. Sex‐related difference was found in the tissue distribution. The drug levels in the tissues of female rats were about two to three times higher than those in male counterparts. The highest level was observed in liver, then in kidney, heart, pancreas, lung and spleen, but no G004 was detected in brain. G004 was slowly eliminated from female rats compared with male rats. There was no long‐term accumulation of G004 in male or female rat tissues. Copyright © 2014 John Wiley & Sons, Ltd.
Principles and levels of Mediterranean connectivity: Evidence from Prada's “Made in Worlds” brand strategy
Authors: Visconti Luca M. , Di Giuli Alberta
Published: May 2014

Mediterranean marketing is an ideological approach to marketing grounded on a corpus of distinctive values characterizing the market orientation of companies located both within and beyond the Mediterranean basin. Among Mediterranean values, this study focuses on connectivity, a largely under‐researched construct in marketing. Through an in‐depth analysis of Prada's “Made in Worlds” branding strategy, we extend both conceptualization of and managerial guidance on marketing connectivity. In detail, we identify the following: (i) three principles guiding connectivity (spatial, temporal, and disciplinary connectivity); (ii) two levels of reification (product and retail level) that translate this strategy into practice; and (iii) two types of connectivity (institutionalized and deliberate connectivity) that differ in breadth and origin of strategy. Copyright © 2014 John Wiley & Sons, Ltd.
Alienable gifts: Uses and meanings of gold in Turkey
Authors: Ertimur Burçak , Sandιkcι Özlem
Published: May 2014

Gold coins and bracelets, standardized and generic items readily available in every jewelry shop, feature predominantly in gift exchange in Turkey. In this study, we investigate why these objects are valued, what they mean to people, and how they are used. Through in‐depth interviews and ethnographic observations, we identify three occasions that gifts of gold take a prominent role. First, we discuss giving gold coins and bracelets in ritualized occasions and locate this traditional practice within a system of economically embedded solidarity. Second, we explain self‐gifting of gold items and discuss how such gift giving enables consumers to exercise self‐control. Finally, we look at how gold gifts serve as means for women to build socioeconomic power and discuss traditional and modern versions of gold accumulation. Overall, we observe that, in the context of Turkish consumer culture, gifting of gold contains a bundle of meanings that cannot be polarized into utilitarian or symbolic. Gold gifts serve multiple purposes simultaneously, and economic motives do not necessarily contradict with and jeopardize the social nature of gift‐giving behavior. Gold coins and bracelets stand as ambiguous objects that maintain their commodity status and financial value and at the same time gain relational and symbolic value. The appeal of gold gifts lies in their ability to navigate between the economic and the social, without subordinating one to the other. Copyright © 2014 John Wiley & Sons, Ltd.
Motivations behind acquiring tattoos and feelings of regret: Highlights from an Eastern Mediterranean context
Authors: Atik Deniz , Yιldιrιm Cansu
Published: May 2014

Tattoos have been a part of everyday life through the ages in diverse cultures. Its beginnings can be traced to the Mediterranean. Despite often being considered as a deviant act, the popularity of tattoos has increased during the last decades. Accordingly, investigating the motivations behind acquiring tattoos has become relevant in diverse academic fields, especially in the West. However, in parallel to the increase in tattoo consumption, the feelings of regret have also increased, which have been studied less in previous literature. Considering this research lack, through a qualitative inquiry with tattoo makers and consumers, this study sheds further light on both the motivations of acquiring tattoos, which mostly concentrate on the desire for self‐expression, and the reasons for regret, which can mainly be categorized as social and physical. Our results contribute to previous research, especially by expanding the discussion regarding the tattoo modifications and showing the cultural differences regarding the perceptions of tattoos in an Eastern Mediterranean context. Copyright © 2014 John Wiley & Sons, Ltd.
On the trail of supply side authenticity: Paradoxes and compromises emerging from an action research
Authors: Ranfagni Silvia , Guercini Simone
Published: May 2014

The paper investigates authenticity in supply chain, applying the concept of self‐authentication to analyse authentic productions resulting from an authentic supply chain. Adopting the method of action research, the authors accompany the planning and creation of an extended local textile and apparel supply chain based on the native wool produced by autochthonous Tuscan sheep. The research studies native wool's self‐authentications along the supply chain together with the related compromises and paradoxes. The methodology used is based on a mixture of qualitative techniques that has favoured researcher participation in the context of analysis. Copyright © 2014 John Wiley & Sons, Ltd.
Comparison of the Reactivity of Carbohydrate Photoaffinity Probes with Different Photoreactive Groups
Authors: Sakurai Kaori , Ozawa Shimpei , Yamada Rika , Yasui Tomoki , Mizuno Sakae
Published: May 2014

A judicious choice of photoreactive group is critical in successful photoaffinity labeling studies of small molecule–protein interactions. A set of carbohydrate‐based photoaffinity probes was prepared to compare the effects of three major photoreactive groups on the efficiency and selectivity of crosslinking a binding protein with low affinity. We showed that, despite the low crosslinking yield, the diazirine probe displayed the high ligand‐dependent reactivity consistent with the ideal mechanism of photoaffinity labeling. Moreover, we demonstrated that, among the three photoreactive groups, only the diazirine probe achieved highly selective crosslinking of a low‐affinity binding protein in cell lysate.
Biosynthetic Code for Divergolide Assembly in a Bacterial Mangrove Endophyte
Authors: Xu Zhongli , Baunach Martin , Ding Ling , Peng Huiyun , Franke Jakob , Hertweck Christian
Published: May 2014

Divergolides are structurally diverse ansamycins produced by a bacterial endophyte (Streptomyces sp.) of the mangrove tree Bruguiera gymnorrhiza. By genomic analyses a gene locus coding for the divergolide pathway was detected. The div gene cluster encodes genes for the biosynthesis of 3‐amino‐5‐hydroxybenzoate and the rare extender units ethylmalonyl‐CoA and isobutylmalonyl‐CoA, polyketide assembly by a modular type I polyketide synthase (PKS), and enzymes involved in tailoring reactions, such as a Baeyer–Villiger oxygenase. A detailed PKS domain analysis confirmed the stereochemical integrity of the divergolides and provided valuable new insights into the formation of the diverse aromatic chromophores. The bioinformatic analyses and the isolation and full structural elucidation of four new divergolide congeners led to a revised biosynthetic model that illustrates the formation of four different types of ansamycin chromophores from a single polyketide precursor.
Synthesis of Fluorinated Heteroaromatics through Formal Substitution of a Nitro Group by Fluorine under Transition‐Metal‐Free Conditions
Authors: Guo Ran‐Ning , Cai Xian‐Feng , Shi Lei , Chen Zhang‐Pei , Zhou Yong‐Gui
Published: May 2014

An efficient and transition‐metal‐free approach was developed to access a series of fluorinated heteroaromatics in moderate to excellent yields. This one‐pot procedure features a triple‐relay transformation of rapid dearomatization, fluorination, and rearomatization processes, which represents a conceptually novel strategy of combining partial hydrogenation and electrophilic fluorination.
Pipeline pattern in an object‐oriented, task‐parallel environment
Authors: Chow Jonathan , Giacaman Nasser , Sinnen Oliver
Published: May 2014

Task parallelism is an approach to parallel programming that has recently gained traction because of its compatibility with the predominant object‐oriented languages and its low overhead compared to threading approaches. Parallel Task is an Open Source task‐parallel compiler and runtime system for object‐oriented languages, in particular Java. It is very flexible and expressive, demonstrated by the fact that it can be directly employed to implement most parallel computing patterns. The only notable exception has been the pipeline pattern where many data items are streamed through a number of processing stages. This is not surprising, as task parallelism is generally not compatible with the pipeline pattern. In this paper, we investigate how the pipeline pattern can be elegantly and efficiently implemented in a task‐parallel environment. To do so, we extend Parallel Task with the concept of implicit futures to allow creating pipelines in an intuitive and object‐oriented manner. Our experimental evaluation uses the extended Parallel Task to implement pipelines of different lengths and characteristics and compares with manual implementations. The evaluation demonstrates very good performance and scalability of the proposed task‐parallel pipeline approach. Copyright © 2014 John Wiley & Sons, Ltd.
Computer‐Assisted Synthesis Optimisation of Inorganic–Organic Hybrid Compounds Using the Local Optimisation Algorithm BOBYQA
Authors: Schilling Lars‐Hendrik , Niekiel Felicitas , Stock Norbert , Hartke Bernd
Published: May 2014

The local, deterministic optimisation algorithm BOBYQA (bound optimisation by quadratic approximation) was applied for the computer‐assisted optimisation of inorganic–organic hybrid compounds. Four proof‐of‐concept studies were performed: 1) increasing the crystallinity and 2) inhibiting the crystallisation of [Ca(H2O)2(H2PMBC)2] (H2PMBC−=−HO3P‐CH2‐C4H6‐COOH), 3) increasing the crystal size of [Bi(H2O)(BTC)] (BTC3−=benzene‐1,3,5‐tricarboxylate) and 4) tuning the particle sizes of [Al(OH)(CDC)]⋅x H2O (CDC2−=trans‐1,4‐cyclohexane dicarboxylate) to a desired value. The measurable quantities of crystallinity, crystal size and hydrodynamic diameter were used as the quality criteria for the optimisation, and the parameters of reaction time and temperature, molar ratios and overall concentration of the starting materials as well as the stirring rate were varied. The crystallinity of [Ca(H2O)2(H2PMBC)2] was increased in three optimisation steps by approximately 14 %, which was accompanied by an increase in crystal size by a factor of approximately 40. These crystals were suitable for structure determination from single‐crystal X‐ray diffraction data. The crystallisation of the same compound could be completely inhibited and clear solutions were obtained. The average crystal size of [Bi(H2O)(BTC)] was increased from (22.2±4.5) to (34.8±9.5) μm and the upper limit increased from 30.0 to 57.7 μm over the course of the optimisation. For the application in Bragg stacks, the variation of particle sizes of [Al(OH)(CDC)]⋅x H2O was studied. Although we aimed at a decrease to 100 nm, a lower limit of 460 nm and polydispersity index of 0.03 were accomplished. The convergence of the algorithm indicates that the optimisation progress is close to completion and the found value for the particle size is close to the lower limit in the system of the chosen parameters. These proofs‐of‐concept studies demonstrate the potential of optimisation algorithms like BOBYQA in synthesis optimisation experiments. At the same time, the convergence behaviour of the algorithm gives an indication of the progress of an optimisation.
PtM/Ba/Al2O3Ce0.6Zr0.4O2: Influence of Synergetic Interactions between Transition Metal and Platinum on NOx Storage and Reduction
Authors: Chen Zhilin , Wang Xiuyun , Wang Ruihu
Published: May 2014

PtM/Ba/ACZ (M=Mn, Fe, and Co) and Pt/Ba/ACZ were prepared using Al2O3Ce0.6Zr0.4O2 (ACZ) as a support. XRD analysis shows Ce0.6Zr0.4O2 solid solution was formed in the ACZ support, and M addition results in a slight shift of the characteristic peaks of Ce0.6Zr0.4O2 to higher 2θ value. A strong interaction between Pt and the transition metals was confirmed by X‐ray absorption fine structure experiments. The effects of transition‐metal addition on NOx storage and reduction, sulfur resistance, and regeneration of PtM/Ba/ACZ were explored. In general, the addition of Co is favorable for NOx storage and reduction, and the addition of Co and Fe facilitates sulfur desorption and regeneration of sulfated samples. Interestingly, if the Pt content is lowered from 1.0 wt % in Pt/Ba/ACZ to 0.5 wt % in PtCo/Ba/ACZ, higher NOx storage capacity and comparable reduction properties are demonstrated.
Catalytic Depolymerization of Lignin in Supercritical Ethanol
Authors: Huang Xiaoming , Korányi Tamás I. , Boot Michael D. , Hensen Emiel J. M.
Published: May 2014

One‐step valorization of soda lignin in supercritical ethanol using a CuMgAlOx catalyst results in high monomer yield (23 wt %) without char formation. Aromatics are the main products. The catalyst combines excellent deoxygenation with low ring‐hydrogenation activity. Almost half of the monomer fraction is free from oxygen. Elemental analysis of the THF‐soluble lignin residue after 8 h reaction showed a 68 % reduction in O/C and 24 % increase in H/C atomic ratios as compared to the starting Protobind P1000 lignin. Prolonged reaction times enhanced lignin depolymerization and reduced the amount of repolymerized products. Phenolic hydroxyl groups were found to be the main actors in repolymerization and char formation. 2D HSQC NMR analysis evidenced that ethanol reacts by alkylation and esterification with lignin fragments. Alkylation was found to play an important role in suppressing repolymerization. Ethanol acts as a capping agent, stabilizing the highly reactive phenolic intermediates by O‐alkylating the hydroxyl groups and by C‐alkylating the aromatic rings. The use of ethanol is significantly more effective in producing monomers and avoiding char than the use of methanol. A possible reaction network of the reactions between the ethanol and lignin fragments is discussed.
Compressed CO2 Accelerated the Synthesis of Mesoporous Heteroatom‐Substituted Aluminophosphates for Enhanced Catalytic Activity
Authors: Wang Fangxiao , Liang Lin , Ma Jun , Shi Lei , Sun Jianmin
Published: May 2014

AFI‐structured zeolites of aluminophosphates AlPO‐5 and heteroatom‐substituted aluminophosphates MeAPO‐5 (Me = Fe, Co) have been synthesized in the presence of compressed CO2, the synthesized materials exhibiting mesoporosity without the use of additional mesotemplates. The mesoporosity was introduced by CO2‐in‐water emulsions acting as mesotemplate during the crystallization of the zeolites. In addition, the crystallization time was shortened in compressed CO2 compared with the conventional synthesis in the absence of CO2. The synthesized aluminophosphates MeAPO‐5 (Me = Fe, Co) displayed much higher activities in the oxidation of styrene than conventional aluminophosphates MeAPO‐5 (Me = Fe, Co) due to the presence of mesopores in the former catalysts, which favor the diffusion of reactants and products. The compressed CO2 method provides a simple, green, and economic route to hierarchical zeolites, which are of great importance for industrial applications.
Chiral N(H)‐tBu and N(H)‐Ad NiII Complexes of Glycine Schiff Bases: Deduction of a Mode of Kinetic Diastereoselectivity
Authors: Maestro Miguel A. , Avecilla Fernando , Sorochinsky Alexander E. , Ellis Trevor K. , Aceña José Luis , Soloshonok Vadim A.
Published: May 2014

The results reported herein have led to the discovery of a novel mode of kinetic diastereoselectivity in the alkylation of N‐tert‐butyl‐ and N‐(1‐adamanyl)‐containing NiII complexes of glycine Schiff bases. It arises from a significant difference in the steric shielding between the N‐H and N‐tBu/Ad sides of the NiII coordination plane, directing the incoming electrophile towards the former.
Carbofuran Induced Oxidative Stress Mediated Alterations in Na+‐K+‐ATPase Activity in Rat Brain: Amelioration by Vitamin E
Authors: Jaiswal Sunil Kumar , Siddiqi Nikhat Jamal , Sharma Bechan
Published: May 2014

Pesticides cause oxidative stress and adversely influence Na+‐K+‐ATPase activity in animals. Since impact of carbofuran has not been properly studied in the mammalian brain, the ability of carbofuran to induce oxidative stress and modulation in Na+‐K+‐ATPase activity and its amelioration by vitamin E was performed. The rats divided into six groups received two different doses of carbofuran (15% and 30% LD50) for 15 days. The results suggested that the carbofuran treatment caused a significant elevation in levels of malonaldehyde and reduced glutathione and sharp inhibition in the activities of super oxide dismutase, catalase, and glutathione‐S‐transferase; the effect being dose dependent. Carbofuran at different doses also caused sharp reduction in the activity of Na+‐K+‐ATPase. The pretreatment of vitamin E, however, showed a significant recovery in these indices. The pretreatment of rats with vitamin E offered protection from carbofuran‐induced oxidative stress.
A Straightforward One‐Pot Synthesis of 3,4‐Dihydroquinazoline‐2(1H)‐thione Derivatives in Aqueous Organic Solvent
Authors: Ding Qiuping , Yao Shujuan , Yang Qin , Sang Xiaoyan , Yu Weihua , Peng Yiyuan
Published: May 2014

A novel and efficient method has been developed for the synthesis of a series of 3,4‐dihydroquinazoline‐2(1H)‐thione derivatives in aqueous organic solvent starting from 3‐(2‐aminophenyl)acrylates with isothiocyanates via a tandem intermolecular nucleophilic addition/intramolecular Michael addition reaction under mild conditions. A broad substrate scope has been demonstrated, which shows wide functional group tolerance and chemical specialization. The efficiency of the methodology could make this process available on gram‐scale.
Synthesis and Photooxygenation of Linear and Angular Furocoumarin Derivatives as a Hydroxyl Radical Source: Psoralen, Pseudopsoralen, Isopseudopsoralen, and Allopsoralen
Authors: Elgogary Sameh Ramadan , Hashem Neveen Mohamed , Khodeir Mohamed Nabeel
Published: May 2014

Synthesis of linear and angular furocoumarins with new skeleton structure of potential photobiological feature interest was carried out through Williamson reaction of hydroxycoumarins with 3‐chloro‐2‐butanone followed by cyclization with polyphosphoric acid or by heating in a strongly alkaline solution. The photooxygenation reactions of synthesized furocoumarins were performed in chloroform and in the presence of tetraphenylporphyrin as singlet oxygen sensitizer (1O2). The photooxygenation reactions afforded the photocleaved product through [2 + 2] cycloaddition and the photooxygenated products through ene reaction and [4 + 2] cycloaddition. The photoproducts were isolated and fully characterized by spectral analyses.
Tandem Synthesis of Bicyclic ortho‐Aminocarbonitrile Derivatives in Ionic Liquids
Authors: Wan Y. , Zhang X‐X. , Zhao L‐L. , Wang C. , Chen L‐F. , Liu G‐X. , Huang S‐Y. , Yue S‐N. , Zhang W‐L. , Wu H.
Published: May 2014

An efficient synthesis of 2‐amino‐4a,5,6,7‐tetrahydronaphthalene‐1,3,3(4H)‐tricarbonitriles via the tandem four‐component condensation of one equivalent of aromatic aldehyde, cyclohexanone, and two equivalents of malononitrile in ionic liquids was undertaken. Up to four new bonds and one new ring were formed in one‐pot with water as the only by‐product in this multi‐component procedure.
Synthesis and Tautomeric Structure of Tris(arylazo) Derivatives of Novel 1H‐Bis‐imidazo[1,2‐b:2′,1′‐e]pyrazole Ring System
Authors: Shawali Ahmad Sami , Farghaly Thoraya A. , Shehata Mohamed R. , Hussein Shadia M.
Published: May 2014

An efficient and convenient synthesis of tris(arylazo) derivatives of novel heterocyclic ring system, namely, 1H‐bis‐imidazo[1,2‐b:2′,1′‐e]pyrazole, is described. The structures of the compounds prepared and their tautomeric structure were elucidated on the basis of their elemental analyses and spectral data in addition to correlation of their acidity constants by Hammett equation. The mechanism of the studied reactions and their site selectivity are discussed.
Synthesis, Antiproliferative, and c‐Src Kinase Inhibitory Activities of 4‐Oxo‐4H‐1‐benzopyran Derivatives
Authors: Chand Karam , Tiwari Rakesh K , Kumar Sumit , Shirazi Amir Nasrolahi , Sharma Sweta , Van der Eycken Erik V , Parmar Virinder S , Parang Keykavous , Sharma Sunil K
Published: May 2014

A new class of 4‐oxo‐4H‐1‐benzopyran derivatives were synthesized and their antiproliferative activity examined against a panel of three human cancer cell lines, that is, breast carcinoma (MDA‐MB‐468), ovarian adenocarcinoma (SK‐OV‐3), and colorectal adenocarcinoma (HT‐29). Two compounds, that is, 3‐hexyl‐7,8‐dihydroxy‐4‐oxo‐4H‐1‐benzopyran and (E)‐ethyl 3‐(7‐methoxy‐4‐oxo‐4H‐1‐benzopyran‐3‐yl)acrylate were found to be potent against all three cancer cell lines studied at 50 μM concentration. Also, the inhibitory potency of the compounds was evaluated against active Src kinase. A few of these compounds exhibited modest Src kinase inhibitory activity (IC50 = 52–57 μM). Structure‐activity relationship studies with respect to the nature and position of substituents on the lead compounds could be further exploited for the design and development of more potent antiproliferative agents and/or Src kinase inhibitors.
Triethylamine‐Catalyzed Synthesis of Oxazepine from Maleamic Acids
Authors: Badru Rahul , Singh Baldev
Published: May 2014

2‐Thioxo‐1,3‐oxazepine‐4,7‐dione compounds were obtained via triethylamine‐catalyzed condensation of maleamic acids with thiophosgene under anhydrous conditions. This method features relatively a simple methodology, use of inexpensive reagents, convenient operating conditions and high yields.
The interface between nacre and bone after implantation in the sheep: a nanotomographic and Raman study
Authors: Pascaretti‐Grizon Florence , Libouban Hélène , Camprasse Georges , Camprasse Serge , Mallet Romain , Chappard Daniel
Published: May 2014

Orthopedic bone devices can be prepared from the shells of giant pearl oysters. Nacre is biocompatible and composed of calcium carbonate (aragonite). Direct welding of bone onto the biomaterial surface has been reported but poorly investigated. Nacre from Pinctada maxima was used to prepare plates, screws and rods. Five sheep were implanted in the first metatarsus under general anesthesia and killed 2 months later. Bones were harvested and fixed in formalin. Analysis was performed by nanotomography and histology after embedding in poly(methyl methacrylate). Polished sections were imaged by scanning electron microscopy then analyzed on a Raman microscope. Nanotomography and histology evidenced the newly apposed bone composed of thin trabeculae with a lower mineralization than mature bone. Erosion of the nacre was also easily observed. The bone/nacre interface presented a characteristic toothed‐comb appearance. Raman spectroscopy identified the typical bands of aragonite (1091 and 711 cm−1) in the devices. At a distance from the interface, the bone matrix presented the typical bands of hydroxyapatite at 960, 1044 and 594–610 cm−1 with the amide bands of collagen at 1250 cm−1. At the bone/nacre interface, a phosphate‐rich layer was observed without proteins. The newly formed bone units exhibited a band at 1075 cm−1 corresponding to a high amount of B‐carbonate substitution. The carbonate/phosphate ratio decreased between new and mature bone, and crystallinity was improved. Raman spectroscopy confirmed the modifications of the bone matrix around the nacre implant and the direct apposition of bone without an interposing organic layer between the calcium carbonate (nacre) and the calcium phosphate (hydroxyapatite). Copyright © 2014 John Wiley & Sons, Ltd.
Cleft lip–cleft palate in Zimbabwe: Estimating the distribution of the surgical burden of disease using geographic information systems
Authors: Tollefson Travis T. , Shaye David , Durbin‐Johnson Blythe , Mehdezadeh Omid , Mahomva Leonard , Chidzonga Midion
Published: May 2014

Objectives/Hypothesis

To evaluate the prevalence and unmet need for cleft lip–cleft palate reconstructive surgery by using incidence. Our hypotheses were that the age of presentation to screening clinics will decrease between 2006 and 2012, and the geospatial distribution of cases will expand to a more rural catchment area.

Study Design

Longitudinal cross‐sectional/geospatial distribution study.

Methods

An online, secure database was created from intake forms for children with cleft lip–cleft palate (N = 604) in Zimbabwe (2006–2012). Univariate analysis was completed. A linear regression model was fitted to test the time trend of a child's age at the time of presentation. Unique patient addresses (n = 411) were matched. Maps presenting cleft diagnosis and presentation year were created with geographic information systems (GIS) software.

Results

The median age of presentation was greater for isolated cleft palate (4.2 years, n = 106) than isolated cleft lip (1.5 years, n = 251) and cleft lip–cleft palate (2.0 years, n = 175). Cleft lip cases were mostly left sided with equal gender distribution. The overall age of presentation remained stable (P = .83). The age of children with isolated cleft palate decreased by 0.8 years per surgical trip (P = .01), suggesting the prevalence of unrepaired cleft palate is decreasing due to local and visiting surgeons. The catchment area extended to a less populous area, but clustered around Harare and Bulawayo.

Conclusions

This study gives Zimbabwe‐specific evidence that supports reports of the persistent burden of disease requiring attention. The GIS software provided data for the primary needs assessment, which will direct communication to healthcare providers and prospective patients outside of the current catchment area.

Level of Evidence

3 Laryngoscope, 125:S1–S14, 2015