bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing Decision Support through Calculating Utility Weighted Contract Prices
Authors: Strydom D.B. , Grové B.
Published: September 2015

Worldwide, table (fresh) and processing potatoes represent major marketing channels. In South Africa, uncertainties influence marketing and production decisions. Producers need to decide on the channel most suited to their needs based on its characteristics. A decision support system (DSS) developed in this study provides producers with relevant price-related information. It evaluates gross production values (GPVs), risk quantifications and utility weighted premiums for both channels. The processing market had the highest GPV in a cumulative distribution function. For South Africa, the processing market had the highest probability of better price based on price and yield risk. Stochastic efficiency with respect to a function (SERF) was used to calculate a utility break-even price, incorporating different risk aversion levels. A utility break-even price of R1,618/ton creates indifference between the two channels for a neutral risk-averse producer. The DSS provides a valuable tool for producers and processors and may be replicated for other commodities and global markets with similar challenges.
The Windmill Approach
Authors: Leonardo Wilson José , Bijman Jos , Slingerland M.A.
Published: September 2015

A common theoretical approach for understanding smallholder farmers' choice of sales arrangements is transaction cost economics (TCE), which usually focuses on a single transaction. However, farmers produce different crops and participate in several value chains simultaneously. Based on two case studies in central Mozambique, the authors propose an analytical framework that pays attention to both the production and the transaction strategies of farmers. This Windmill Approach acknowledges that farmers decide on participating in various value chains on the basis of multiple objectives and aspirations. Farmers prioritize the allocation of available resources towards the sustainability of the whole farm. Policy to support smallholder farmers' market access should not focus on single transactions, but on the combination of farming system and value chain costs and benefits.
Impact Assessment of Greening and the Issue of Nitrogen-Fixing Crops
Authors: Solazzo Roberto , Donati Michele , Arfini Filippo
Published: September 2015

In the CAP reform 2014–2020, the ‘green’ component of direct payments remunerates environmental services and includes three greening requirements: crop diversification, maintenance of permanent grassland and establishment of an ecological focus area (EFA). This paper evaluates the effect of ‘greening’ and payment redistribution on farm incomes and land use, considering two different hypotheses of the EFA weighting factor (Ewf) for nitrogen-fixing crops. The evaluation is developed at farm level by a positive mathematical programming (PMP) model and applied to more than 2,000 farms in northern Italy. The results show that crop diversification will mainly affect the cereal area, with significant reductions in maize and wheat, while the EFA requirement, especially with the lower Ewf, will boost the spread of protein crops. Nevertheless, ‘greening’ does not significantly affect farm income, while greater economic effects are mainly due to the redistribution of direct payments.
The Effects of Household Wealth on Adoption of Agricultural Related Climate Change Adaptation Strategies in Zambia
Authors: Kuntashula Elias , Chabala Lydia M. , Chibwe Terence K. , Kaluba Peter
Published: September 2015

Despite increased emphasis targeting climate change adaptation strategies towards the poorer sections of communities, few adoption studies assess the uptake of these practices by these groups in a systematic and comprehensive manner. In this study, we used a combination of participatory rapid approaches and quantitative principal component analysis to determine each household’s wealth status, and to assess the relationship between wealth and the adoption of various agricultural related climate change adaptation strategies. Evidence from a random sample of 1231 households across six districts of Zambia showed that the more well-endowed households than their poorly endowed counter parts, adopted most of the climate change adaptation strategies. The relatively well-endowed households had a high probability of 10.6%, 9.5%, 7.1%, and 5.5% to embrace crop rotation, minimum tillage, fertiliser trees and change crop varieties due to climate change, respectively, than their poorly endowed counter parts. Most, if not all of these strategies require some level of resource investment hence only those households who could afford such resources are most likely to adopt them. The influence of household resource endowment on the uptake of several climate change adaptation strategies call for the subsidising of the relatively poor endowed households to encourage adoption of these strategies among this category of farmers.
Development of Monoclonal Hybridoma Cell Lines and Extracting Antibody Against Fummonisin B1
Authors: Guangyu Yang  , Wenxue Li  , Xiaoyun Liang  , Jinyin Wu  , Wei Zhu
Published: September 2015

Objective:To acquire monoclonal hybridoma cell lines against fummonisin B1(FB1) and extract monoclonal antibody against FB1.Methods: Coupling antigens of FB1-KLH and FB1-BSA with chemical methods and immune 6-8 weeks old femaleBALB/c mice with FB1-KLH. Integrating spleen cells with sp2/0 myeloma cells to acquire hybridoma cell lines secreting McAb against FB1. The method of multiple subclones was used to select cell lines stably secreting McAb. McAbs was got from ascites and purified. The subclass of antibody was measured and the molecular weight was identified. The specificity and sensitivity of McAb were identified with indirect competitive inhibition ELISA.Results:The results of serum from immuned mice showed that after five times of immunization the titer stables at 1×10-6, and the McAb belongs to IgG1 subclass, the light chain was ?, the molecular weight of heavy and light chain were 55kDa and 32kDa, respectively. ELISA results showed that McAb could react with FB1. The linear range indirect competitive inhibition ELISA is 10-500ng/ml.Conclusion:The monoclonal hybridoma cell lines and the high specificity,high sensitivity of FB1-McAb was got.
Introduction: Social Network Analysis Applications in Complex Governance Networks
Authors: Kapucu Naim
Published: September 2015

The growth in studying complexity, governance, and networks is a noticeable fact. Complex public policy problems require productive collaborations among multiple actors from different sectors. Public, private, and not-for-profit organizations work through governance networks and collaborative governance to solve complex public policy problems. There is a strong interest in both the practice and theory of networks in public governance. This interest has given boost to the use of social network analysis (SNA) in studies on complex governance networks. This special issue of Complexity, Governance, & Networks, includes theoretically, conceptually, and analytically rigorous papers with social network analysis applications. The papers help our understanding in studying complex governance networks.
Sea ice convergence along the Arctic coasts of Greenland and the Canadian Arctic Archipelago: Variability and extremes (1992–2014)
Authors: Kwok Ron
Published: September 2015

After the summer of 2013, a convergence‐induced tail in the thickness distribution of the ice cover is found along the Arctic coasts of Greenland and Canadian Arctic Archipelago. Prompted by this, a normalized ice convergence index (ICI) is introduced to examine the variability and extremes in convergence in a 23 year record (1992–2014) of monthly ice drift. Large‐scale composites of circulation patterns, characteristic of regional convergence and divergence, are examined. Indeed, the ICI shows the June 2013 convergence event to be an extreme (i.e., ICI > 2). Furthermore, there is a cluster of 9 months over a 17 month period with positive ICIs (i.e., >1) following the record summer minimum ice extent (SMIE) in 2012; the imprint of ice dynamics from this cluster of positive ICIs likely contributed to higher SMIEs in 2013 and 2014. The impact of convergence on SMIE is discussed, and the increase in Arctic ice volume in 2013 is underscored.
Funktionsorientiertes Design von Aerogelen: Selbstanordnung von legierten PdNi‐Hohlnanosphären als effiziente Elektrokatalysatoren
Authors: Cai Bin , Wen Dan , Liu Wei , Herrmann Anne‐Kristin , Benad Albrecht , Eychmüller Alexander
Published: September 2015

Eine gezielte Verbesserung der Baueinheiten ist eine naheliegende Herangehensweise, um Aerogele mit herausragenden Eigenschaften zu versehen und gleichzeitig ihre Vorzüge zu erhalten. Bestimmte Eigenschaften, wie die Optimierung der Morphologie für katalytische Anwendungen oder die Übergangsmetalldotierung in metallischen Aerogelen, sind jedoch nach wie vor schwer zu realisieren. In diesem Zusammenhang präsentieren wir hier erstmalig elektrokatalytisch aktive Aerogele, welche sich vollständig aus legierten PdNi‐Hohlnanosphären (HNS) aufbauen und deren chemische Zusammensetzung und Schalendicke gezielt eingestellt werden kann. Die Kombination von Übergangsmetalldotierung mit hohlen Baueinheiten in einem dreidimensionalen Netzwerk machen PdNi‐HNS‐Aerogele zu vielversprechenden Elektrokatalysatoren für die Ethanoloxidation. Gegenüber dem kommerziellen Pd/C‐Katalysator zeigt das Pd83Ni17‐HNS‐Aerogel eine 5.6‐fach höhere Massenaktivität. Durch diese Arbeit wird die Nutzbarkeit von metallischen Aerogelen in der Elektrokatalyse erweitert, indem die Morphologie und Zusammensetzung der Baueinheiten gezielt kontrolliert werden.
Exklusiver π‐Einschluss leichter Alkalimetallkationen durch ein neutrales Molekül
Authors: Bertermann Rüdiger , Braunschweig Holger , Constantinidis Philipp , Dellermann Theresa , Dewhurst Rian D. , Ewing William C. , Fischer Ingo , Kramer Thomas , Mies Jan , Phukan Ashwini K. , Vargas Alfredo
Published: September 2015

Kation‐π‐Wechselwirkungen sind eine der wichtigsten Klassen von nichtkovalenten Bindungen. Sie können in der Biologie, Chemie und den Materialwissenschaften beobachtet werden. Jedoch spielen diese bisher nur in Verbindung mit sehr starken kovalenten oder dativen Bindungen eine Rolle, was dazu führt, dass nur wenige Beispiele mit ausschließlich Kation‐π‐Bindungen bekannt sind. In dieser Arbeit wurde gezeigt, dass ein neutrales Diborin in der Lage war, die leichten Alkalimetallkationen Li+ und Na+ in Abwesenheit von Ladungen, kovalenten Bindungen oder Elektronenpaardonoren einzuschließen. Die entstehenden Einschlusskomplexe sind gemäß unserem Kenntnisstand die ersten strukturell belegten Beispiele, in welchen ein neutrales Molekül leichte Alkalimetall‐Kationen ausschließlich durch Kation‐π‐Wechselwirkungen bindet.
An Atomic‐Scale View of CO and H2 Oxidation on a Pt/Fe3O4 Model Catalyst
Authors: Bliem Roland , van der Hoeven Jessi , Zavodny Adam , Gamba Oscar , Pavelec Jiri , de Jongh Petra E. , Schmid Michael , Diebold Ulrike , Parkinson Gareth S.
Published: September 2015

Metal–support interactions are frequently invoked to explain the enhanced catalytic activity of metal nanoparticles dispersed over reducible metal oxide supports, yet the atomic‐scale mechanisms are rarely known. In this report, scanning tunneling microscopy was used to study a Pt1‐6/Fe3O4 model catalyst exposed to CO, H2, O2, and mixtures thereof at 550 K. CO extracts lattice oxygen atoms at the cluster perimeter to form CO2, creating large holes in the metal oxide surface. H2 and O2 dissociate on the metal clusters and spill over onto the support. The former creates surface hydroxy groups, which react with the support, ultimately leading to the desorption of water, while oxygen atoms react with Fe from the bulk to create new Fe3O4(001) islands. The presence of the Pt is crucial because it catalyzes reactions that already occur on the bare iron oxide surface, but only at higher temperatures.
Organomediated Enantioselective 18F Fluorination for PET Applications
Authors: Buckingham Faye , Kirjavainen Anna K. , Forsback Sarita , Krzyczmonik Anna , Keller Thomas , Newington Ian M. , Glaser Matthias , Luthra Sajinder K. , Solin Olof , Gouverneur Véronique
Published: September 2015

The first organomediated asymmetric 18F fluorination has been accomplished using a chiral imidazolidinone and [18F]N‐fluorobenzenesulfonimide. The method provides access to enantioenriched 18F‐labeled α‐fluoroaldehydes (>90 % ee), which are versatile chiral 18F synthons for the synthesis of radiotracers. The utility of this process is demonstrated with the synthesis of the PET (positron emission tomography) tracer (2S,4S)‐4‐[18F]fluoroglutamic acid.
Manganese‐Catalyzed Direct Nucleophilic C(sp2)H Addition to Aldehydes and Nitriles
Authors: Zhou Bingwei , Hu Yuanyuan , Wang Congyang
Published: September 2015

Herein, a manganese‐catalyzed nucleophilic addition of inert C(sp2)H bonds to aldehydes and nitriles is disclosed by virtue of a dual activation strategy. The reactions feature mild reaction conditions, excellent regio‐ and stereoselectivity, and a wide substrate scope, which includes both aromatic and olefinic CH bonds, as well as a large variety of aldehydes and nitriles. Moreover, mechanistic studies shed light on possible catalytic cycles.
Energy Migration Upconversion in Manganese(II)‐Doped Nanoparticles
Authors: Li Xiyan , Liu Xiaowang , Chevrier Daniel M. , Qin Xian , Xie Xiaoji , Song Shuyan , Zhang Hongjie , Zhang Peng , Liu Xiaogang
Published: September 2015

We report the synthesis and characterization of cubic NaGdF4:Yb/Tm@NaGdF4:Mn core–shell structures. By taking advantage of energy transfer through Yb→Tm→Gd→Mn in these core–shell nanoparticles, we have realized upconversion emission of Mn2+ at room temperature in lanthanide tetrafluoride based host lattices. The upconverted Mn2+emission, enabled by trapping the excitation energy through a Gd3+ lattice, was validated by the observation of a decreased lifetime from 941 to 532 μs in the emission of Gd3+ at 310 nm (6P7/2→8S7/2). This multiphoton upconversion process can be further enhanced under pulsed laser excitation at high power densities. Both experimental and theoretical studies provide evidence for Mn2+ doping in the lanthanide‐based host lattice arising from the formation of F− vacancies around Mn2+ ions to maintain charge neutrality in the shell layer.
Inhibition of Osteoarthritis by Adipose‐Derived Stromal Cells Overexpressing Fra‐1 in Mice
Authors: Schwabe Kay , Garcia Mireia , Ubieta Kenia , Hannemann Nicole , Herbort Bettina , Luther Julia , Noël Daniele , Jorgensen Christian , Casteilla Louis , David Jean‐Pierre , Stock Michael , Herrmann Martin , Schett Georg , Bozec Aline
Published: September 2015

Objective

To determine whether overexpression of the activator protein 1 (AP‐1) transcription factor Fra‐1 in adipose‐derived stromal cells (ADSCs) is an effective treatment of collagenase‐induced osteoarthritis (OA).

Methods

OA was induced by injection of collagenase into the knee joints of male C57BL/6 mice. ADSCs were isolated from the inguinal fat pads of 8‐week‐old wild‐type or Fra‐1–transgenic mice and injected into the knee joints of mice with collagenase‐induced OA 7 days after OA induction. Histologic analyses of cartilage destruction and chondrocyte cell death were performed. Adipogenic differentiation capacity was evaluated, gene expression was analyzed, and cytokine profiling was performed in stromal vascular fractions (SVFs) and ADSCs.

Results

OA‐related cartilage destruction and chondrocyte cell death were significantly reduced in mouse knee joints treated with ADSCs from Fra‐1–transgenic mice compared to mouse knee joints treated with ADSCs from wild‐type mice. This effect did not result from the higher number of adipogenic progenitors observed in SVFs from Fra‐1–transgenic compared to wild‐type mouse fat pads, since injection of wild‐type mouse ADSCs enriched for adipogenic progenitors did not show any additional chondroprotective effects compared to nonsorted ADSCs. However, Fra‐1–transgenic mouse ADSCs showed decreased adipogenic differentiation capacity. Moreover, Fra‐1 significantly inhibited proinflammatory interleukin‐6 and pentraxin 3 expression, while increasing the expression of extracellular matrix proteins, such as periostin and spondin 1. These findings suggest that Fra‐1 overexpression leads to an increased chondroprotective effect of ADSCs in OA.

Conclusion

ADSCs overexpressing Fra‐1 effectively protect against OA. Our data indicate that genetic modifications of ADSCs, such as Fra‐1 overexpression, may improve their potential to protect articular cartilage against OA‐mediated damage.
Analyzing and optimizing pedestrian flow through a topological network based on M/G/C/C and network flow approaches
Authors: Khalid Ruzelan , Baten Md. Azizul , Nawawi Mohd. Kamal Mohd. , Ishak Nurhanis
Published: September 2015

An M/G/C/C state dependent queuing network measures the performance of a system whose service rate decreases with the increasing number of residing entities. However, the performance in terms of throughputs, levels of congestions, the expected number of entities, and the expected service time is typically analyzed based on a series of arrival rates without any further discussion on the optimal arrival rate. This paper derives the optimal arrival rates of corridors in a topological network using calculus and numerical analysis approaches. These optimal rates are then used as capacity parameters in the network's flow model to obtain the optimal arrival rates that maximize its total throughput. To ease the construction and performance evaluation of the network, we design and construct an M/G/C/C framework based on the Object‐Oriented Programming approach that integrates the lingo software as an optimization tool. The framework is then tested on virtual and real networks. This framework can be used to develop a more advanced traffic management tool for studying and managing traffic flow through a complex network. Copyright © 2015 John Wiley & Sons, Ltd.
How rods respond to single photons: Key adaptations of a G‐protein cascade that enable vision at the physical limit of perception
Authors: Reingruber Jürgen , Holcman David , Fain Gordon L.
Published: September 2015

Rod photoreceptors are among the most sensitive light detectors in nature. They achieve their remarkable sensitivity across a wide variety of species through a number of essential adaptations: a specialized cellular geometry, a G‐protein cascade with an unusually stable receptor molecule, a low‐noise transduction mechanism, a nearly perfect effector enzyme, and highly evolved mechanisms of feedback control and receptor deactivation. Practically any change in protein expression, enzyme activity, or feedback control can be shown to impair photon detection, either by decreasing sensitivity or signal‐to‐noise ratio, or by reducing temporal resolution. Comparison of mammals to amphibians suggests that rod outer‐segment morphology and the molecules and mechanism of transduction may have evolved together to optimize light sensitivity in darkness, which culminates in the extraordinary ability of these cells to respond to single photons at the ultimate limit of visual perception.
Molecular modeling and multi‐spectroscopic approaches to study the interaction between antibacterial drug and human immunoglobulin G
Authors: Wang Qin , Min Suotian , Liu Zhifeng , Zhang Shengrui
Published: September 2015

Mechanistic and conformational studies on the interaction of sulfamethoxazole (SMX) with human immunoglobulin G (HIgG) were performed by molecular modeling and multi‐spectroscopic methods. The interaction mechanism was firstly predicted through molecular modeling that confirmed the interaction between SMX and HIgG. The binding parameters and thermodynamic parameters at different temperatures had been calculated according to the Stern−Volmer, Scatchard, Sips and Van ’t Hoff equations, respectively. Experimental results showed that the fluorescence intensity of HIgG was quenched by the gradual addition of SMX. The binding constants of SMX with HIgG decreased with the increase of temperature, which meant that the quenching mechanism was a static quenching. Meanwhile, the results also confirmed that there was one independent class of binding site on HIgG for SMX during their interaction. The thermodynamic parameters of the reaction, namely standard enthalpy ΔH0 and entropy ΔS0, had been calculated to be −14.69 kJ·mol−1 and 22.99 J·mol−1·K−1, respectively, which suggested that the electrostatic and hydrophobic interactions were the predominant intermolecular forces in stabilizing the SMX−HIgG complex. Furthermore, experimental results obtained from three‐dimensional fluorescence spectroscopy, UV−vis absorption spectroscopy and circular dichroism (CD) spectroscopy confirmed that the conformational structure of HIgG was altered in the presence of SMX. Copyright © 2015 John Wiley & Sons, Ltd.
Micro 3D cell culture systems for cellular behavior studies: Culture matrices, devices, substrates, and in‐situ sensing methods
Authors: Choi Jonghoon , Lee Eun Kyu , Choo Jaebum , Yuh Junhan , Hong Jong Wook
Published: September 2015

Microfabricated systems equipped with 3D cell culture devices and in‐situ cellular biosensing tools can be a powerful bionanotechnology platform to investigate a variety of biomedical applications. Various construction substrates such as plastics, glass, and paper are used for microstructures. When selecting a construction substrate, a key consideration is a porous microenvironment that allows for spheroid growth and mimics the extracellular matrix (ECM) of cell aggregates. Various bio‐functionalized hydrogels are ideal candidates that mimic the natural ECM for 3D cell culture. When selecting an optimal and appropriate microfabrication method, both the intended use of the system and the characteristics and restrictions of the target cells should be carefully considered. For highly sensitive and near‐cell surface detection of excreted cellular compounds, SERS‐based microsystems capable of dual modal imaging have the potential to be powerful tools; however, the development of optical reporters and nanoprobes remains a key challenge. We expect that the microsystems capable of both 3D cell culture and cellular response monitoring would serve as excellent tools to provide fundamental cellular behavior information for various biomedical applications such as metastasis, wound healing, high throughput screening, tissue engineering, regenerative medicine, and drug discovery and development.
Quantitative determination of pravastatin and its metabolite 3α‐hydroxy pravastatin in plasma and urine of pregnant patients by LC‐MS/MS
Authors: Zhang Xing , Vernikovskaya Daria I. , Wang Xiaoming , Nanovskaya Tatiana N. , Costantine Maged , Hankins Gary D. V. , Ahmed Mahmoud S.
Published: September 2015

This report describes the development and validation of a chromatography/tandem mass spectrometry method for the quantitative determination of pravastatin and its metabolite (3α‐hydroxy pravastatin) in plasma and urine of pregnant patients under treatment with pravastatin, as part of a clinical trial. The method includes a one‐step sample preparation by liquid–liquid extraction. The extraction recovery of the analytes ranged between 93.8 and 99.5% in plasma. The lower limits of quantitation of the analytes in plasma samples were 0.106 ng/mL for pravastatin and 0.105 ng/mL for 3α‐hydroxy pravastatin, while in urine samples they were 19.7 ng/mL for pravastatin and 2.00 ng/mL for 3α‐hydroxy pravastatin. The relative deviation of this method was <10% for intra‐ and interday assays in plasma and urine samples, and the accuracy ranged between 97.2 and 106% in plasma, and between 98.2 and 105% in urine. The method described in this report was successfully utilized for determining the pharmacokinetics of pravastatin in pregnant patients enrolled in a pilot clinical trial for prevention of preeclampsia. Copyright © 2015 John Wiley & Sons, Ltd.
Ultrafast Photoinduced Charge Separation in Wide‐Band‐Capturing Self‐Assembled Supramolecular Bis(donor styryl)BODIPY–Fullerene Conjugates
Authors: Shao Shuai , Gobeze Habtom B. , Karr Paul A. , D'Souza Francis
Published: September 2015

A new series of self‐assembled supramolecular donor–acceptor conjugates capable of wide‐band capture, and exhibiting photoinduced charge separation have been designed, synthesized and characterized using various techniques as artificial photosynthetic mimics. The donor host systems comprise of a 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) containing a crown ether entity at the meso‐position and two styryl entities on the pyrrole rings. The styryl end groups also carried additional donor (triphenylamine or phenothiazine) entities. The acceptor host system was a fulleropyrrolidine comprised of an ethylammonium cation. Owing to the presence of extended conjugation and multiple chromophore entities, the BODIPY host revealed absorbance and emission well into the near‐IR region covering the 300–850 nm spectral range. The donor–acceptor conjugates formed by crown ether–alkyl ammonium cation binding of the host–guest system was characterized by optical absorbance and emission, computational, and electrochemical techniques. Experimentally determined binding constants were in the range of 1–2×105 M−1. An energy‐level diagram to visualize different photochemical events was established using redox, computational, absorbance, and emission data. Spectral evidence for the occurrence of photoinduced charge separation in these conjugates was established from femtosecond transient absorption studies. The measured rates indicated ultrafast charge separation and relatively slow charge recombination revealing their usefulness in light‐energy harvesting and optoelectronic device applications. The bis(donor styryl)BODIPY‐derived conjugates populated their triplet excited states during charge recombination.
Proton Transverse Relaxation as a Sensitive Probe for Structure Determination in Solid Proteins
Authors: Rovó Petra , Grohe Kristof , Giller Karin , Becker Stefan , Linser Rasmus
Published: September 2015

Solid‐state nuclear magnetic resonance (NMR) spectroscopy has been successfully applied to elucidate the atomic‐resolution structures of insoluble proteins. The major bottleneck is the difficulty to obtain valuable long‐distance structural information. Here, we propose the use of distance restraints as long as 32 Å, obtained from the quantification of transverse proton relaxation induced by a methanethiosulfonate spin label (MTSL). Combined with dipolar proton–proton distance restraints, this method allows us to obtain protein structures with excellent precision from single spin‐labeled 1 mg protein samples using fast magic angle spinning.
Cytochrome P450 2D6 and 3A4 enzyme inhibition by amine stimulants in dietary supplements
Authors: Liu Yitong , Santillo Michael F.
Published: September 2015

A number of dietary supplements used for weight loss and athletic performance enhancement have been recently shown to contain a variety of stimulants, for which there is a lack of pharmacological and toxicological information. One concern for these emerging compounds is their potential to inhibit metabolic enzymes in the liver such as cytochromes P450 (CYP), which can lead to unexpected interactions among dietary supplements, drugs, and other xenobiotics. In this study, inhibition of human recombinant CYP2D6 and CYP3A4 by 27 amine stimulants associated with dietary supplements and their analogs was evaluated by luminescence assays. The strongest CYP2D6 inhibitors were coclaurine (IC50 = 0.14 ± 0.01 μM) and N‐benzylphenethylamine (IC50 = 0.7 ± 0.2 μM), followed by several other relatively strong inhibitors (IC50, 2–12 μM) including β‐methylphenethylamine, N,β‐dimethylphenethylamine (phenpromethamine), 1,3‐dimethylamylamine (DMAA), N,α‐diethylphenethylamine, higenamine (norcoclaurine) and N,N‐diethylphenethylamine. Only nine compounds inhibited CYP3A4 by 20–55% at 100 μM. Results of this study illustrate that several amine stimulants associated with dietary supplements inhibit CYP2D6 and CYP3A4 in vitro, and these compounds may participate in adverse drug‐dietary supplement interactions in vivo. Copyright © 2015 John Wiley & Sons, Ltd.
Beryllepin, C6H6Be, and “Beryllium‐Inserted Benzenes,” C6H6Ben, n = 2–6: A Density Functional Computational Investigation
Authors: Tabares Annette A. , Waters Essene L. , Zoellner Robert W.
Published: September 2015

The seven‐membered beryllium‐containing heterocycle beryllepin, C6H6Be, has been examined computationally at the B3LYP/6‐311++G** density functional level of theory. Beryllepin is best described as a planar singlet heterocyclic conjugated triene with marginal aromatic character containing a C–Be–C moiety forced to be nonlinear (∠C‐Be‐C = 146.25°) by the cyclic constraints of the seven‐membered ring. The molecule can be considered to be derived from a benzene‐like system in which a neutral beryllium atom has been inserted between two adjacent carbon atoms. The 11 other possible “beryllium‐inserted benzenes,” C6H6Ben, n = 2–6, have also been investigated. Only two of these heterocyclic systems, the eight‐membered 1,4‐diberyllocin and the nine‐membered 1,4,7‐triberyllonin, were found to be stable, singlet‐ground‐state systems, albeit with little aromatic character. Of the remaining nine beryllium‐inserted benzenes, with the exception of the 11‐membered ring containing five beryllium atoms and the 12‐membered ring containing six beryllium atoms, which were calculated to exist as a ground state pentet and septet, respectively, all were calculated to be ground state triplet systems.
Recent advances in optical fiber devices for microfluidics integration
Authors: Blue Robert , Uttamchandani Deepak
Published: September 2015

This paper examines the recent emergence of miniaturized optical fiber based sensing and actuating devices that have been successfully integrated into fluidic microchannels that are part of microfluidic and lab‐on‐chip systems. Fluidic microsystems possess the advantages of reduced sample volumes, faster and more sensitive biological assays, multi‐sample and parallel analysis, and are seen as the de facto bioanalytical platform of the future. This paper considers the cases where the optical fiber is not merely used as a simple light guide delivering light across a microchannel, but where the fiber itself is engineered to create a new sensor or tool for use within the environment of the fluidic microchannel.

Detection and trapping of molecules can be achieved with optical fibers directly located within the fluidic microchannel.

magnified image

Detection and trapping of molecules can be achieved with optical fibers directly located within the fluidic microchannel.
Reflections on Becoming an Older and More Experienced Psychotherapist
Authors: Kantrowitz Judy L.
Published: September 2015

In this article, I describe how greater self‐awareness and increased affect tolerance changed my clinical work with patients. I provide a clinical example to illustrate how my personal growth occurred. Blind spots, created through both conflict and ignorance, are discussed. My acceptance of my limitations in general, as well as those that come with age, and the awareness of the limitations of time itself all increase as I age. Grief and mourning become more central in my work. My comfort and confidence increase, but awareness of my age makes me more selective about whom I will treat. I treasure the work more than ever and experience the benefits of mutual peer supervision increasing over time. I hope to convey what a privilege it has been to be a psychotherapist.
Functional impairment in older liver transplantation candidates: From the functional assessment in liver transplantation study
Authors: Wang Connie W. , Covinsky Kenneth E. , Feng Sandy , Hayssen Hilary , Segev Dorry L. , Lai Jennifer C.
Published: September 2015

The emerging epidemic of older patients with cirrhosis has led to a sharp increase in the number of ≥65 year olds considering liver transplantation (LT). However, clinicians lack objective measures to risk stratify older patients. We aimed to determine whether the short physical performance battery (SPPB), a well‐validated geriatric measure of physical function, has greater prognostic value in older versus younger LT candidates. Adult outpatients listed for LT with laboratory Model for End‐Stage Liver Disease score ≥ 12 underwent physical function testing using the SPPB, consisting of gait speed, chair stands, and balance. Patients were categorized by age (“younger,” < 65 years; “older,” ≥ 65 years) and SPPB (“impaired,” ≤ 9; “robust,” > 9). Competing risks models associated age and SPPB with wait‐list death/delisting. Of 463 LT candidates, 21% were ≥ 65 years and 18% died or were delisted. Older patients had slower gait (1.1 versus 1.3 m/seconds; P < 0.001), a trend of slower chair stands (12.8 versus 11.8 seconds; P = 0.06), and a smaller proportion able to complete all balance tests (65% versus 78%; P = 0.01); SPPB was lower in older versus younger patients (10 versus 11; P = 0.01). When compared to younger robust patients as a reference group, younger impaired patients (hazard ratio [HR], 1.77; P = 0.03) and older impaired patients (HR, 2.70; P = 0.003) had significantly higher risk of wait‐list mortality, but there was no difference in risk for older robust patients (HR 1.38; P = 0.35) [test of equality, P = 0.01]. After adjustment for Model for End‐Stage Liver Disease‐sodium (MELD‐Na) score, only older impaired patients had an increased risk of wait‐list mortality compared to younger robust patients (HR, 2.36; P = 0.01; test of equality P = 0.05). In conclusion, functional impairment, as assessed by the SPPB, predicts death/delisting for LT candidates ≥65 years independent of MELD‐Na. Further research into activity‐based interventions to reduce adverse transplant outcomes in this population is warranted. Liver Transpl 21:1465‐1470, 2015. © 2015 AASLD.
Conversion of once‐daily extended‐release tacrolimus is safe in stable liver transplant recipients: A randomized prospective study
Authors: Kim Jong Man , Kwon Choon Hyuck David , Joh Jae‐Won , Sinn Dong Hyun , Lee Sanghoon , Choi Gyu‐Seong , Lee Suk‐Koo
Published: September 2015

Simplifying the therapeutic regimen of liver transplantation (LT) recipients may help prevent acute rejection and graft failure. The present study aimed to evaluate the efficacy and safety of conversion from twice‐daily tacrolimus to once‐daily extended‐release tacrolimus under concurrent mycophenolate mofetil therapy in stable LT recipients. This randomized, prospective, controlled study included 91 patients who underwent LTs with at least 1 year of posttransplant follow‐up. Conversion was made on a 1 mg to 1 mg basis. No incidences of biopsy‐proven acute rejection, graft failure, or death were reported in either group at 24 weeks. Median serum tacrolimus level of the study group was 20% less than that of the control group at 8 weeks. However, no significant differences regarding biochemical indicators of liver function or serum creatinine levels were observed between the 2 groups. Adverse event (AE) profiles were similar for both groups, with comparable incidences of AEs and serious AEs. No significant differences regarding efficacy or safety were observed between the once‐daily tacrolimus and twice‐daily tacrolimus groups of stable LT recipients. In conclusion, our study suggests that tacrolimus can be safely converted from a twice‐daily regimen to a once‐daily regimen in stable LT recipients. Liver Transpl 22:209–216, 2016, 2015. © 2015 AASLD.
Beta oscillations in freely moving Parkinson's subjects are attenuated during deep brain stimulation
Authors: Quinn Emma J. , Blumenfeld Zack , Velisar Anca , Koop Mandy Miller , Shreve Lauren A. , Trager Megan H. , Hill Bruce C. , Kilbane Camilla , Henderson Jaimie M. , Brontë‐Stewart Helen
Published: September 2015

Background

Investigations into the effect of deep brain stimulation (DBS) on subthalamic (STN) beta (13‐30 Hz) oscillations have been performed in the perioperative period with the subject tethered to equipment. Using an embedded sensing neurostimulator, this study investigated whether beta power was similar in different resting postures and during forward walking in freely moving subjects with Parkinson's disease (PD) and whether STN DBS attenuated beta power in a voltage‐dependent manner.

Methods

Subthalamic local field potentials were recorded from the DBS lead, using a sensing neurostimulator (Activa® PC+S, Medtronic, Inc., Food and Drug Administration– Investigational Device Exemption (IDE)‐, institutional review board–approved) from 15 PD subjects (30 STNs) off medication during lying, sitting, and standing, during forward walking, and during randomized periods of 140 Hz DBS at 0 V, 1 V, and 2.5/3 V. Continuous video, limb angular velocity, and forearm electromyography recordings were synchronized with neural recordings. Data were parsed to avoid any movement or electrical artifact during resting states.

Results

Beta power was similar during lying, sitting, and standing (P = 0.077, n = 28) and during forward walking compared with the averaged resting state (P = 0.466, n = 24), although akinetic rigid PD subjects tended to exhibit decreased beta power when walking. Deep brain stimulation at 3 V and at 1 V attenuated beta power compared with 0 V (P < 0.003, n = 14), and this was voltage dependent (P < 0.001).

Conclusions

Beta power was conserved during resting and forward walking states and was attenuated in a voltage‐dependent manner during 140‐Hz DBS. Phenotype may be an important consideration if this is used for closed‐loop DBS. © 2015 International Parkinson and Movement Disorder Society
Body image and quality of life of breast cancer patients: influence of timing and stage of breast reconstruction
Authors: Teo Irene , Reece Gregory P. , Christie Israel C. , Guindani Michele , Markey Mia K. , Heinberg Leslie J. , Crosby Melissa A. , Fingeret Michelle Cororve
Published: September 2015

Objective

The process of cancer‐related breast reconstruction is typically multi‐staged and can take months to years to complete, yet few studies have examined patient psychosocial well‐being during the reconstruction process. We investigated the effects of reconstruction timing and reconstruction stage on body image and quality of life at specific time points during the breast reconstruction process.

Methods

In this cross‐sectional study, 216 patients were grouped into four reconstructive stages: pre‐reconstruction, completed stage 1, completed stage 2, and final stages. Multiple regression analyses examined the roles of reconstruction timing (immediate vs delayed reconstruction) and reconstruction stage as well as their interaction in predicting body image and quality of life, controlling for patient age, BMI, type of reconstruction, chemotherapy, radiation therapy, and major complication(s).

Results

A difference in pattern of body image was observed across the reconstructive stages, with those receiving delayed reconstruction showing significant decrease in body image dissatisfaction compared with those with immediate reconstruction. At pre‐reconstruction, patients awaiting delayed reconstruction reported significantly lower social well‐being compared with those awaiting immediate reconstruction. Reconstruction stage predicted emotional well‐being, with higher emotional well‐being observed in those who had commenced reconstruction.

Conclusions

Timing and stage of reconstruction are important to consider when examining psychosocial outcomes of breast cancer patients undergoing reconstruction. Those waiting to initiate delayed reconstruction appear at particular risk for body image, emotional, and social distress. Our findings have implications for delivery of psychosocial treatment to maximize body image and quality of life of patients undergoing cancer‐related breast reconstruction.Copyright © 2015 John Wiley & Sons, Ltd.
Measurement method of plasma current and density in atmospheric pressure plasma jet
Authors: Yambe Kiyoyuki , Saito Hiroki , Ogura Kazuo
Published: September 2015

We present a measurement method of the plasma current and density in an atmospheric‐pressure plasma generated using a quartz tube, helium gas, and copper foil electrode by applying a high RF voltage. The plasma in the form of a bullet is released as a plume or jet into the atmosphere. To study the characteristics of the atmospheric‐pressure plasma, the plasma current is measured using a current probe, and the drift velocity of plasma plume is measured using a photodetector. The current of the plasma plume is estimated by subtracting the ground line current from the power line current in the circuit. The density of plasma plumenis estimated from the plasma plume currentIand the drift velocityvasI=envS, whereSis the cross section of plasma plume. The density of the released plasma into the atmosphere is estimated as ∼1018m−3by the method. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Oxidative stress by inorganic nanoparticles
Authors: Tee Jie Kai , Ong Choon Nam , Bay Boon Huat , Ho Han Kiat , Leong David Tai
Published: September 2015

Metallic and metallic oxide nanoparticles (NPs) have been increasingly used for various bio‐applications owing to their unique physiochemical properties in terms of conductivity, optical sensitivity, and reactivity. With the extensive usage of NPs, increased human exposure may cause oxidative stress and lead to undesirable health consequences. To date, various endogenous and exogenous sources of oxidants contributing to oxidative stress have been widely reported. Oxidative stress is generally defined as an imbalance between the production of oxidants and the activity of antioxidants, but it is often misrepresented as a single type of cellular stress. At the biological level, NPs can initiate oxidative stress directly or indirectly through various mechanisms, leading to profound effects ranging from the molecular to the disease level. Such effects of oxidative stress have been implicated owing to their small size and high biopersistence. On the other hand, cellular antioxidants help to counteract oxidative stress and protect the cells from further damage. While oxidative stress is commonly known to exert negative biological effects, measured and intentional use of NPs to induce oxidative stress may provide desirable effects to either stimulate cell growth or promote cell death. Hence, NP‐induced oxidative stress can be viewed from a wide paradigm. Because oxidative stress is comprised of a wide array of factors, it is also important to use appropriate assays and methods to detect different pro‐oxidant and antioxidant species at molecular and disease levels. WIREs Nanomed Nanobiotechnol 2016, 8:414–438. doi: 10.1002/wnan.1374

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Emerging Technologies

Nanotechnology Approaches to Biology > Nanoscale Systems in Biology

Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials
The Canadian Management of Bovine Spongiform Encephalopathy in Historical and Scientific Perspective, 1990-2014
Authors: Quimby Alexandra E. , Shamy Michel C.F.
Published: September 2015

On February 11, 2015, the Canadian Food Inspection Agency announced that a cow born and raised in Alberta had tested positive for bovine spongiform encephalopathy (BSE), commonly known as mad cow disease. BSE is a prion disease of cattle that, when transmitted to humans, produces a fatal neurodegenerative disease known as variant Creutzfeldt-Jakob disease. We believe that this latest case of BSE in Canadian cattle suggests the timeliness of a review of the management of BSE in Canada from a historically and scientifically informed perspective. In this article, we ask: how did the Canadian management of BSE between 1990 and 2014 engage with the contemporary understanding of BSE’s human health implications? We propose that Canadian policies largely ignored the implicit medical nature of BSE, treating it as a purely agricultural and veterinary issue. In this way, policies to protect Canadians were often delayed and incomplete, in a manner disturbingly reminiscent of Britain’s failed management of BSE. Despite assurances to the contrary, it is premature to conclude that BSE (and with it the risk of variant Creutzfeldt-Jakob disease) is a thing of Canada’s past: BSE remains very much an issue in Canada’s present.
The effects of cannabis on memory function in users with and without a psychotic disorder: findings from a combined meta-analysis
Authors: Schoeler T. , Kambeitz J. , Behlke I. , Murray R. , Bhattacharyya S.
Published: September 2015

Background.

Effect of cannabis use on memory function is a contentious issue, with effects being different in healthy individuals and patients with psychosis.

Method.

Employing a meta-analytic approach we investigated the effects of cannabis use on memory function in patients with psychosis and healthy individuals, and the effect of diagnosis, memory dimension and moderating factors. A total of 88 studies were identified through a systematic literature search, investigating healthy (n = 7697) and psychotic (n = 3261) individuals. Standardized mean differences between the cannabis user and non-user groups on memory tasks were estimated using random-effects models and the effect-size statistic Cohen's d. Effects of potential moderating factors were tested using mixed-effects models and subgroup analyses.

Results.

We found that cannabis use was associated with significantly (p ⩽ 0.05) impaired global (d = 0.27) and prospective memory (d = 0.61), verbal immediate (d = 0.40) and delayed (d = 0.36) recall as well as visual recognition (d = 0.41) in healthy individuals, but a better global memory (d = −0.11), visual immediate recall (d = −0.73) and recognition (d = −0.42) in patients. Lower depression scores and younger age appeared to attenuate the effects of cannabis on memory. Cannabis-using patients had lower levels of depression and were younger compared with non-using patients, whilst healthy cannabis-users had higher depression scores than age-matched non-users. Longer duration of abstinence from cannabis reduced the effects on memory in healthy and patient users.

Conclusions.

These results suggest that cannabis use is associated with a significant domain-specific impairment in memory in healthy individuals but not in cannabis-using patients, suggesting that they may represent a less developmentally impaired subgroup of psychotic patients.
‘I know it exists … but I haven't experienced it personally’: older Canadian men's perceptions of ageism as a distant social problem
Authors: HURD CLARKE LAURA , KOROTCHENKO ALEXANDRA
Published: September 2015

This paper examines how older men perceive, experience and internalise ageist prejudice in the context of their everyday lives. We draw on in-depth interviews with 29 community-dwelling Canadian men aged 65–89. Although one-third of our participants were unfamiliar with the term ageism, the majority felt that age-based discrimination was prevalent in Canadian society. Indicating that they themselves had not been personally subjected to ageism, the men considered age-based discrimination to be a socially distant problem. The men explained their perceived immunity to ageism in terms of their youthful attitudes and active lifestyles. The men identified three groups who they considered to be particularly vulnerable to age-based discrimination, namely women, older workers and frail elders residing in institutions. At the same time, the majority of our participants had internalised a variety of ageist and sexist stereotypes. Indeed, the men assumed that later life was inevitably a time of physical decline and dependence, and accepted as fact that older adults were grumpy, poor drivers, unable to learn new technologies and, in the case of older women, sexually unattractive. In this way, a tension existed between the men's assertion that ageism did not affect their lives and their own internalisation of ageist stereotypes. We consider our findings in relation to the theorising about ageism and hegemonic masculinity.