bluuebunny/crossref_metadata_2025 huggingface dataset:
A Global Detectability Condition for Consensus Tracking of Linear Multi‐Agent Systems with Stochastic Disturbances
Authors: Diao Miao , Duan Zhisheng , Wen Guanghui
Published: October 2014

This paper investigates the consensus tracking problem for both continuous‐ and discrete‐time multi‐agent systems with general linear dynamics and stochastic disturbances under a global detectability condition. It is assumed that there exists a dynamic leader and the subgraph describing the communication topology among the followers is undirected and connected. The proposed global detectability condition extends the traditional local detectability condition to the networked case. By using the relative states of neighboring followers and the relative measurement information of the leader, distributed observer‐type consensus protocols are constructed for both continuous‐ and discrete‐time cases to guarantee all the followers to track the leader. A distinct feature of this paper is that the relative states of the leader are estimated by a group of followers rather than any individual follower. It is found that the mean square tracking errors are bounded even if the leader is not detectable by any follower, where the only requirement is that the leader is globally detectable by followers. Simulation results are finally presented to verify the effectiveness of theoretical results.
The exponential‐Poisson model for recurrent event data: An application to a set of data on malaria in Brazil
Authors: Macera Márcia A. C. , Louzada Francisco , Cancho Vicente G. , Fontes Cor J. F.
Published: October 2014

In this paper, we introduce a new model for recurrent event data characterized by a baseline rate function fully parametric, which is based on the exponential‐Poisson distribution. The model arises from a latent competing risk scenario, in the sense that there is no information about which cause was responsible for the event occurrence. Then, the time of each recurrence is given by the minimum lifetime value among all latent causes. The new model has a particular case, which is the classical homogeneous Poisson process. The properties of the proposed model are discussed, including its hazard rate function, survival function, and ordinary moments. The inferential procedure is based on the maximum likelihood approach. We consider an important issue of model selection between the proposed model and its particular case by the likelihood ratio test and score test. Goodness of fit of the recurrent event models is assessed using Cox‐Snell residuals. A simulation study evaluates the performance of the estimation procedure in the presence of a small and moderate sample sizes. Applications on two real data sets are provided to illustrate the proposed methodology. One of them, first analyzed by our team of researchers, considers the data concerning the recurrence of malaria, which is an infectious disease caused by a protozoan parasite that infects red blood cells.
Bioactive Derivatives of Isopropylstilbene from Mutasynthesis and Chemical Synthesis
Authors: Kronenwerth Max , Brachmann Alexander O. , Kaiser Marcel , Bode Helge B.
Published: October 2014

Isopropylstilbene is a natural product from Photorhabdus luminescens TT01, with multiple biological activities. A mutant deficient in the production of both anthraquinones and cinnamic acid was constructed, thus giving a clean background according to UV detection. This anthraquinone and stilbene deficient (ASD) mutant was used in mutasynthesis experiments to obtain new stilbene derivatives, which were detected by GC–MS. The structures of the new derivatives were confirmed by detailed MS analysis and then chemically synthesised; all of the natural and synthetic compounds were tested against protozoa that cause tropical diseases. Two compounds obtained by mutasynthesis showed the highest activity against Trypanosoma cruzi, the causative agent of Chagas disease, and Leishmania donovani, which causes leishmaniasis.
De‐SOX Performance of Spinels Containing Manganese
Authors: Jiang Ruiyu , Zhang Jiling , Tang Zhe , Cao Yuebin , Xu Ning , Hou Guihua
Published: October 2014

The development of sulfur transfer agents plays a significant role in the environmental pollution control. However, at present, there are only few researches on the addition of active components to the sulfur transfer agent. Using manganese as an active component, the structure of a sulfur transfer agent is regulated through microwave reaction. The influence of the sulfur transfer agent with manganese on oxidative desulfurization performance is analyzed. The results demonstrate the key role of manganese as an active component in the reduction reaction process by pulse reduction reaction.
Enzymatic Fuel Cells Solely Supplied with Unpurified Cellobiose Dehydrogenase and Laccase in Microorganism’s Culture Supernatants
Authors: Sané Sabine , Heilemann Corinna , Salavei Pavel , Rubenwolf Stefanie , Jolivalt Claude , Madzak Catherine , Zengerle Roland , Nielsen Peter J. , Kerzenmacher Sven
Published: October 2014

Enzymatic electrodes have great potential for catalysing the direct conversion of chemical compounds into electricity with the use of redox enzymes. However, expensive and time‐consuming enzyme purification and the frequent need to add mediators are considered as drawbacks of enzymatic electrodes. We report a biofuel cell at pH 5, supplied with the unpurified enzymes laccase and cellobiose dehydrogenase (CDH) in crude culture supernatant, without the further addition of mediators. A maximum power output of 6.2±1.2 μW cm−2 was achieved by using supernatants containing laccase from Trametes versicolor (2.84 UmL−1) and CDH (0.90 UmL−1) from a recombinant yeast Yarrowia lipolytica YPC4. In comparison, the supply of purified enzymes (laccase: 2.40 UmL−1, CDH: 0.15 UmL−1) in a buffer solution yielded only about a twofold higher power density. Our results demonstrate the feasibility of using unpurified laccase and CDH in an enzymatic biofuel cell, which can simplify its construction and operation.
Poly(N‐vinylpyrrolidone)‐Decorated Reduced Graphene Oxide with ZnO Grown In Situ as a Cathode Buffer Layer for Polymer Solar Cells
Authors: Hu Ting , Chen Lie , Yuan Kai , Chen Yiwang
Published: October 2014

A ZnO@reduced graphene oxide–poly(N‐vinylpyrrolidone) (ZnO@RGO‐PVP) nanocomposite, prepared by in situ growth of ZnO nanoparticles on PVP‐decorated RGO (RGO‐PVP) was developed as a cathode buffer layer for improving the performance of polymer solar cells (PSCs). PVP not only favors homogeneous distribution of the RGO through the strong π–π interactions between graphene and PVP molecules, but also acts as a stabilizer and bridge to control the in situ growth of sol–gel‐derived ZnO nanoparticles on the surface of the graphene. At the same time, RGO provides a conductive connection for independent dispersion of ZnO nanoparticles to form uniform nanoclusters with fewer domain boundaries and surface traps. Moreover, the LUMO level of ZnO is effectively improved by modification with RGO‐PVP. Compared to bare ZnO, a ZnO@RGO‐PVP cathode buffer layer substantially reduces the recombination of carriers, increases the electrical conductivity, and enhances electron extraction. Consequently, the power conversion efficiency of an inverted device based on thieno[3,4‐b]thiophene/benzodithiophene (PTB7):[6,6]‐phenyl C71‐butyric acid methyl ester (PC71BM) with ZnO@RGO‐PVP as cathode buffer layer was greatly improved to 7.5 % with improved long‐term stability. The results reveal that ZnO@RGO‐PVP is universally applicable as a cathode buffer layer for improving the performance of PSCs.
Sulfur‐Impregnated Core–Shell Hierarchical Porous Carbon for Lithium–Sulfur Batteries
Authors: Zhang Fei‐Fei , Huang Gang , Wang Xu‐Xu , Qin Yu‐Ling , Du Xin‐Chuan , Yin Dong‐Ming , Liang Fei , Wang Li‐Min
Published: October 2014

Core–shell hierarchical porous carbon spheres (HPCs) were synthesized by a facile hydrothermal method and used as host to incorporate sulfur. The microstructure, morphology, and specific surface areas of the resultant samples have been systematically characterized. The results indicate that most of sulfur is well dispersed over the core area of HPCs after the impregnation of sulfur. Meanwhile, the shell of HPCs with void pores is serving as a retard against the dissolution of lithium polysulfides. This structure can enhance the transport of electron and lithium ions as well as alleviate the stress caused by volume change during the charge–discharge process. The as‐prepared HPC‐sulfur (HPC‐S) composite with 65.3 wt % sulfur delivers a high specific capacity of 1397.9 mA h g−1 at a current density of 335 mA g−1 (0.2 C) as a cathode material for lithium–sulfur (Li‐S) batteries, and the discharge capacity of the electrode could still reach 753.2 mA h g−1 at 6700 mA g−1 (4 C). Moreover, the composite electrode exhibited an excellent cycling capacity of 830.5 mA h g−1 after 200 cycles.
Reversible Reduction of Oxatriphyrin(3.1.1)—Adjusting the Coordination Abilities to the Central Ion
Authors: Pawlicki Miłosz , Kędzia Aneta , Bykowski Dominik , Latos‐Grażyński Lechosław
Published: October 2014

Furan‐fused oxatriphyrin(3.1.1) acts as a ligand towards boron(III), phosphorous(III), and phosphorous(V) ions. The coordination abilities are adjusted by changes of the oxidation state. Two coordination modes are possible, depending on the central‐ion entrapped in the oxatriphyrin(3.1.1) environment. A free base, structurally similar to the complexes, can be easily obtained by regioselective reduction. The resulting molecules are highly emissive after conversion into a phlorin‐like oxatriphyrin(3.1.1) frame (NON donors), and show chiral activity caused by the presence of a tetrahedral carbon.
Podand‐Based Dimeric Chromium(III)–Salen Complex for Asymmetric Henry Reaction: Cooperative Catalysis Promoted by Complexation of Alkali Metal Ions
Authors: Ouyang Guang‐Hui , He Yan‐Mei , Fan Qing‐Hua
Published: October 2014

A new kind of podand‐based dimeric salen ligand was synthesized, and its association with potassium cations was investigated by 1H NMR spectroscopy. The corresponding CrIII–salen dimer was assembled by a supramolecular host–guest self‐assembly process and was then used as a catalyst in highly efficient and enantioselective asymmetric Henry reactions. Regulation by KBArF (BArF=[3,5‐(CF3)2C6H3]4B) led to remarkable improvements in yield (by up to 58 %) and enantioselectivity (for example, from 80 % ee to 96 % ee).
Chemoselective Reductive Nucleophilic Addition to Tertiary Amides, Secondary Amides, and N‐Methoxyamides
Authors: Nakajima Minami , Oda Yukiko , Wada Takamasa , Minamikawa Ryo , Shirokane Kenji , Sato Takaaki , Chida Noritaka
Published: October 2014

As the complexity of targeted molecules increases in modern organic synthesis, chemoselectivity is recognized as an important factor in the development of new methodologies. Chemoselective nucleophilic addition to amide carbonyl centers is a challenge because classical methods require harsh reaction conditions to overcome the poor electrophilicity of the amide carbonyl group. We have successfully developed a reductive nucleophilic addition of mild nucleophiles to tertiary amides, secondary amides, and N‐methoxyamides that uses the Schwartz reagent [Cp2ZrHCl]. The reaction took place in a highly chemoselective fashion in the presence of a variety of sensitive functional groups, such as methyl esters, which conventionally require protection prior to nucleophilic addition. The reaction will be applicable to the concise synthesis of complex natural alkaloids from readily available amide groups.
Novel λ3‐Iodane‐Based Functionalization of Synthetic Carbon Allotropes (SCAs)—Common Concepts and Quantification of the Degree of Addition
Authors: Hof Ferdinand , Schäfer Ricarda A. , Weiss Cornelius , Hauke Frank , Hirsch Andreas
Published: October 2014

The covalent functionalization of carbon allotropes represents a main topic in the growing field of nano materials. However, the development of functional architectures is impeded by the intrinsic polydispersibility of the respective starting material, the unequivocal characterization of the introduced functional moieties, and the exact determination of the degree of functionalization. Based on a novel carbon allotrope functionalization reaction, utilizing λ3‐iodanes as radical precursor systems, we were able to demonstrate the feasibility to separate and to quantify thermally detached functional groups, formerly covalently linked to carbon nanotubes and graphene through thermogravimetric GC‐MS.
Enantioselective Total Synthesis of the Lignan (+)‐Linoxepin
Authors: Tietze Lutz F. , Clerc Jérôme , Biller Simon , Duefert Svenia‐C. , Bischoff Matthias
Published: October 2014

An enantioselective total synthesis of the natural (+)‐linoxepin (1) was accomplished in eleven steps from bromovanin (24). Key steps are a domino carbopalladation/ Mizoroki–Heck reaction with the formation of a pentacyclic system, an asymmetric hydroboration as well as an oxidative lactonization.
Precise Tuning of the Charge Transfer Kinetics and Catalytic Properties of MoS2 Materials via Electrochemical Methods
Authors: Chia Xinyi , Ambrosi Adriano , Sedmidubský David , Sofer Zdeněk , Pumera Martin
Published: October 2014

MoS2 has become particularly popular for its catalytic properties towards the hydrogen evolution reaction (HER). It has been shown that the metallic 1T phase of MoS2, obtained by chemical exfoliation after lithium intercalation, possesses enhanced catalytic activity over the semiconducting 2H phase due to the improved conductivity properties which facilitate charge‐transfer kinetics. Here we demonstrate a simple electrochemical method to precisely tune the electron‐transfer kinetics as well as the catalytic properties of both exfoliated and bulk MoS2‐based films. A controlled reductive or oxidative electrochemical treatment can alter the surface properties of the film with consequently improved or hampered electrochemical and catalytic properties compared to the untreated film. Density functional theory calculations were used to explain the electrochemical activation of MoS2. The electrochemical tuning of electrocatalytic properties of MoS2 opens the doors to scalable and facile tailoring of MoS2‐based electrochemical devices.
Screen‐Printed Calcium–Birnessite Electrodes for Water Oxidation at Neutral pH and an “Electrochemical Harriman Series”
Authors: Lee Seung Y. , González‐Flores Diego , Ohms Jonas , Trost Tim , Dau Holger , Zaharieva Ivelina , Kurz Philipp
Published: October 2014

A mild screen‐printing method was developed to coat conductive oxide surfaces (here: fluorine‐doped tin oxide) with micrometer‐thick layers of presynthesized calcium manganese oxide (Ca–birnessite) particles. After optimization steps concerning the printing process and layer thickness, electrodes were obtained that could be used as corrosion‐stable water‐oxidizing anodes at pH 7 to yield current densities of 1 mA cm−2 at an overpotential of less than 500 mV. Analyses of the electrode coatings of optimal thickness (≈10 μm) indicated that composition, oxide phase, and morphology of the synthetic Ca–birnessite particles were hardly affected by the screen‐printing procedure. However, a more detailed analysis by X‐ray absorption spectroscopy revealed small modifications of both the Mn redox state and the structure at the atomic level, which could affect functional properties such as proton conductivity. Furthermore, the versatile new screen‐printing method was used for a comparative study of various transition‐metal oxides concerning electrochemical water oxidation under “artificial leaf conditions” (neutral pH, fairly low overpotential and current density), for which a general activity ranking of RuO2>Co3O4≈(Ca)MnOx≈NiO was observed. Within the group of screened manganese oxides, Ca–birnessite performed better than “Mn‐only materials” such as Mn2O3 and MnO2.
Synthetic cannabimimetic agents metabolized by carboxylesterases
Authors: Thomsen Ragnar , Nielsen Line M. , Holm Niels B. , Rasmussen Henrik B. , Linnet Kristian ,   the INDICES Consortium
Published: October 2014

Synthetic cannabimimetic agents are a large group of diverse compounds which act as agonists at cannabinoid receptors. Since 2004, synthetic cannabinoids have been used recreationally, although several of the compounds have been shown to cause severe toxicity in humans. In this study, the metabolism of two indazole carboxamide derivatives, AB‐PINACA and AB‐FUBINACA, was investigated by using human liver microsomes (HLM). For both compounds, a major metabolic pathway was the enzymatic hydrolysis of the primary amide, resulting in the major metabolites AB‐PINACA‐COOH and AB‐FUBINACA‐COOH. Other major metabolic pathways were mono‐hydroxylation of the N‐pentyl chain in AB‐PINACA and mono‐hydroxylation of the 1‐amino‐3‐methyl‐1‐oxobutane moiety in AB‐FUBINACA. To identify the enzyme(s) responsible for the amide hydrolysis, incubations with recombinant carboxylesterases and human serum, as well as inhibition studies in HLM and human pulmonary microsomes (HPM) were performed. Carboxylesterase 1 (CES1) was identified as the major human hepatic and pulmonary enzyme responsible for the amide hydrolysis.We employed similar studies to identify the esterase(s) involved in the previously described hydrolytic metabolism of two quinolineindole synthetic cannabinoids, PB‐22 and 5F‐PB‐22, as well as the closely related compound, BB‐22. Our investigations again revealed CES1 to be the key enzyme catalyzing these reactions. The identified major metabolites of AB‐PINACA and AB‐FUBINACA are likely to be useful in documenting drug usage in forensic and clinical screening. Additionally, the identification of CES1 as the main enzyme hydrolyzing these compounds improves our knowledge in the emerging field of xenobiotic metabolism by esterases. Copyright © 2014 John Wiley & Sons, Ltd.
Phylogeography and palaeodistribution modelling of Nassauvia subgenus Strongyloma (Asteraceae): exploring phylogeographical scenarios in the Patagonian steppe
Authors: Nicola Marcela V. , Sede Silvana M. , Pozner Raúl , Johnson Leigh A.
Published: October 2014

The Patagonian steppe is an immense, cold, arid region, yet phylogeographically understudied. Nassauvia subgen. Strongyloma is a characteristic element of the steppe, exhibiting a continuum of morphological variation. This taxon provides a relevant phylogeographical model not only to understand how past environmental changes shaped the genetic structure of its populations, but also to explore phylogeographical scenarios at the large geographical scale of the Patagonian steppe. Here, we (1) assess demographic processes and historical events that shaped current geographic patterns of haplotypic diversity; (2) analyze hypotheses of isolation in refugia, fragmentation of populations, and/or colonization of available areas during Pleistocene glaciations; and (3) model extant and palaeoclimatic distributions to support inferred phylogeographical patterns. Chloroplast intergenic spacers, rpl32–trnL and trnQ–5′rps16, were sequenced for 372 individuals from 63 populations. Nested clade analysis, analyses of molecular variance, and neutrality tests were performed to assess genetic structure and range expansion. The present potential distribution was modelled and projected onto a last glacial maximum (LGM) model. Of 41 haplotypes observed, ten were shared among populations associated with different morphological variants. Populations with highest haplotype diversity and private haplotypes were found in central‐western and south‐eastern Patagonia, consistent with long‐term persistence in refugia during Pleistocene. Palaeomodelling suggested a shift toward the palaeoseashore during LGM; new available areas over the exposed Atlantic submarine platform were colonized during glaciations with postglacial retraction of populations. A scenario of fragmentation and posterior range expansion may explain the observed patterns in the center of the steppe, which is supported by palaeomodelling. Northern Patagonian populations were isolated from southern populations by the Chubut and the Deseado river basins during glaciations. Pleistocene glaciations indirectly impacted the distribution, demography, and diversification of subgen. Strongyloma through decreased winter temperatures and water availability in different areas of its range.
Synthesis of Isotopically Labelled Oligoprenyl Diphosphates and Their Application in Mechanistic Investigations of Terpene Cyclases
Authors: Citron Christian A. , Rabe Patrick , Barra Lena , Nakano Chiaki , Hoshino Tsutomu , Dickschat Jeroen S.
Published: October 2014

A flexible, efficient and robust method for the synthesis of isotopically labelled oligoprenyl diphosphates was developed. The method makes use of just a few building blocks (acetone, triethyl phosphonoacetate, and ethyl acetoacetate) from which several isotopomers with deuterium or 13C‐labelling are commercially available or can be easily obtained by synthesis. Besides these building blocks, a few deuterated reagents were used for the introduction of deuterium labelling. Furthermore, the synthesis of [14‐2H]geranylgeranyl diphosphate is reported. The material was used for a stereochemical analysis of the cyclisation reaction catalysed by tuberculosinyl diphosphate synthase from Mycobacterium tuberculosis.
Synthesis of Vicinal Diketoses by Using a Metathesis–Hydroxylation–Oxidation Sequence
Authors: Menzel Melchior , Ziegler Thomas
Published: October 2014

Symmetrical vicinal diuloses were prepared from 2,3:4,5‐di‐O‐isopropylidene‐D‐arabinose and ‐L‐arabinose by using methyltriphenylphosphonium bromide to convert both enantiomers into the corresponding 1,2‐dideoxy‐3,4:5,6‐di‐O‐isopropylidene‐arabino‐hex‐1‐enitols D‐5 and L‐5. The metathesis reactions of D‐5 with itself and with L‐5, respectively, by using the Hoveyda–Grubbs catalyst gave diastereomeric dec‐5‐enitols DD‐6 and DL‐6, which were dihydroxylated with osmium tetroxide to give 1,2:3,4:7,8:9,10‐tetra‐O‐isopropylidene‐protected decitols DD‐7 and DL‐7. Swern oxidation of the decitols afforded isopropylidene‐protected deco‐5,6‐diuloses DD‐8 and DL‐8, which gave unprotected deco‐5,6‐diuloses DD‐9 and DL‐9 upon acidic cleavage of the isopropylidene groups. The structures of both diastereomers were confirmed by NMR spectroscopy and X‐ray crystal structure analysis.
From intrapsychic to ecological theories in social psychology: Outlines of a functional theory approach
Authors: Fiedler Klaus
Published: October 2014

Social psychology is facing a major developmental task, which is not primarily one of achieving larger data samples and stricter significance testing. What is needed, rather, is an improvement in logic of science and powerful theorizing. The starting point of this article is a critical appraisal that the intrapsychic concepts (motives, attitudes, and explicit and implicit goals) that are the major focus of social–psychological theories lack in explanatory power because they are too close to the effects (actions, judgments, and decisions) they are intended to explain. To overcome this apparent weakness (compared with neuroscience or genetics), it is proposed that more powerful theories should relate social cognition and behavior to more distant variables in the environment. A functional analysis reveals that intrapsychic processes are multiply predetermined by extrapsychic, environmental constraints. The theoretical value and fertility of the proposed ecological functionalism are illustrated with reference to three areas of empirical research: sampling approaches to understanding biases in judgment and decision making; strategic influences on priming effects within a functional analysis of adaptive behavior; and the impact of verbal and symbolic communication constraints on the construction of attributions, stereotypes, and culture. Copyright © 2014 John Wiley & Sons, Ltd.
Seismic response of a case study soft story frame retrofitted using a GIB system
Authors: Agha Beigi Hossein , Christopoulos Constantin , Sullivan Timothy , Calvi Michele
Published: October 2014

This paper presents results from a numerical investigation into the seismic retrofit of a soft story frame using a novel gapped‐inclined brace (GIB) system. The GIB system consists of a pinned brace and a gap element that is added to the first story columns of the frame. The inclusion of GIB elements in addition to increasing the lateral capacity of columns at the first story increases the post‐yield stiffness ratio of the system and reduces the P‐delta effects on the columns, while not increasing the first story lateral resistance or stiffness. This allows for the isolating benefits of the soft story to protect the upper floors of the structure from damage while avoiding excessive deformations and reducing the propensity for collapse.

A six‐story RC frame with masonry infills on all floors except for the first floor is studied. The dynamic response of the retrofitted building using the GIB system is investigated numerically and is compared with the response of the original un‐retrofitted building and the same building in which masonry infills are added to the first story to mitigate the soft story response.

Results from the nonlinear time‐history analyses indicate that the GIB system could provide a reliable seismic retrofit mechanism for soft story buildings, which greatly reduces the likelihood of collapse by increasing the displacement capacity of the soft storey and by reducing P‐delta effects, while minimizing the overall damage and losses in the building by taking advantages of the isolation that is provided by the soft story to the rest of the structure located above. Copyright © 2014 John Wiley & Sons, Ltd.
Development of empirical and analytical fragility functions using kernel smoothing methods
Authors: Noh Hae Young , Lallemant David , Kiremidjian Anne S.
Published: October 2014

Fragility functions that define the probabilistic relationship between structural damage and ground motion intensity are an integral part of performance‐based earthquake engineering or seismic risk analysis. This paper introduces three approaches based on kernel smoothing methods for developing analytical and empirical fragility functions. A kernel assigns a weight to each data that is inversely related to the distance between the data value and the input of the fragility function of interest. The kernel smoothing methods are, therefore, non‐parametric forms of data interpolation. These methods enable the implicit treatment of uncertainty in either or both of ground motion intensity and structural damage without making any assumption about the shape of the resulting fragility functions. They are particularly beneficial for sparse, noisy, or non‐homogeneous data sets. For illustration purposes, two types of data are considered. The first is a set of numerically simulated responses for a four‐story steel moment‐resisting frame, and the second is a set of field observations collected after the 2010 Haiti earthquake. The results demonstrate that these methods can develop continuous representations of fragility functions without specifying their functional forms and treat sparse data sets more efficiently than conventional data binning and parametric curve fitting methods. Moreover, various uncertainty analyses are conducted to address the issues of over‐fitting, bias, and confidence intervals. Copyright © 2014 John Wiley & Sons, Ltd.
Distance Costs and The Degree of Inter‐Partner Involvement in International Relational‐Based Technology Alliances
Authors: van Kranenburg Hans , Hagedoorn John , Lorenz‐Orlean Stefanie
Published: October 2014

This research studies the effect of specific institutional and distance cost issues, in particular the protection of intellectual property rights and geographic distance, on the preference of companies for different governance modalities in terms of the degree of their involvement in international relational‐based technology alliances. In the sample, all technology alliances contain exclusive technology agreements. We find that international differences in intellectual property rights protection regimes between the home countries of partnering companies are a significant factor: the larger the difference, the more likely that partnering companies prefer to form an equity relational‐based technology alliance with substantial inter‐partner involvement. The degree of geographic distance between partners also affects the preference of companies for a particular form of relational‐based agreement. Companies prefer to engage in deeper inter‐partner involvement, albeit of a non‐equity nature, in case of large geographic distance between the home countries of the partnering companies.
Utensil manipulation during initial treatment of pediatric feeding problems
Authors: Wilkins Jonathan W. , Piazza Cathleen C. , Groff Rebecca A. , Volkert Valerie M. , Kozisek Jennifer M. , Milnes Suzanne M.
Published: October 2014

Children with feeding disorders exhibit a variety of problem behaviors during meals. One method of treating problem mealtime behavior is to implement interventions sequentially after the problem behavior emerges (e.g., Sevin, Gulotta, Sierp, Rosica, & Miller, 2002). Alternatively, interventions could target problem behavior in anticipation of its emergence. In the current study, we implemented nonremoval and re‐presentation of bites either on a spoon or on a Nuk for 12 children with feeding problems. The nonremoval and re‐presentation treatment improved feeding behavior for 8 of 12 children. Of those 8 children, 5 had lower levels of expulsions, and 4 of the 8 children had higher levels of mouth clean with the Nuk than with the spoon. We describe the subsequent clinical course of treatment and present follow‐up data for 7 of the 8 children who responded to the nonremoval and re‐presentation treatment with the spoon or Nuk. The data are discussed in terms of potential reasons why the utensil manipulation improved feeding behavior for some children.
Raman spectroscopy analysis of lipid droplets content, distribution and saturation level in Non‐Alcoholic Fatty Liver Disease in mice
Authors: Kochan Kamila , Maslak Edyta , Krafft Christoph , Kostogrys Renata , Chlopicki Stefan , Baranska Malgorzata
Published: October 2014

Non‐Alcoholic Fatty Liver Disease (NAFLD) is a common liver disorder, characterized by an excessive lipids deposition within the hepatic tissue. Due to the lack of clear‐cut symptoms and optimal diagnostic method, the actual prevalence of NAFLD and its pathogenesis remains unclear, especially in the early stages of progression. In the presented work confocal Raman microspectroscopy was used to investigate alterations in the chemical composition of the NAFLD‐affected liver. We have investigated two NAFLD models, representative for macrovesicular and microvesicular steatosis, induced by High Fat Diet (60 kcal %) and Low Carbohydrate High Protein Diet (LCHP), respectively. In both models we confirmed the development of NAFLD, manifested by the presence of lipid droplets (LDs), but of different sizes. Model of macrovesicular steatosis was characterized by large LDs, whereas in the microvesicular steatosis model small droplets were found. In both models, however, we observed a significant decrease in the degree of unsaturation of lipids, in comparison to the control. In addition, for both models, the impact of medical treatment with selected drugs (perindopril and nicotinic acid, respectively) was tested, indicating a significant influence of medicine not only on the occurrence and size of the droplets, but also on their composition. Inboth cases the drug treatment resulted in an increase of the degree of unsaturation of lipids forming droplets. Confocal Raman microspectroscopy was proven to be a powerful tool providing detailed insight into selected areas of hepatic tissue, following the NAFLD pathogenesis and diagnostic potential of the applied drugs.

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Osteoblast response to the surface of amino acid‐functionalized hydroxyapatite
Authors: Lee Wing‐Hin , Loo Ching‐Yee , Chrzanowski Wojciech , Rohanizadeh Ramin
Published: October 2014

Interactions between proteins and the surface of biomaterials are crucial for the biological function and success of materials implanted in the human body. In this study, hydroxyapatite (HA) with negative and positive surface charges were fabricated by functionalizing the HA surface with acidic or basic amino acids. The influence of HA surface charge on protein adsorption and cell activities was studied. The crystallinity, morphology, and surface charge of amino acid‐functionalized HA (AA‐HA) particles and the stability of amino acids on the HA surface were determined. Both AA‐HA and unmodified HA were studied for their capacity to adsorb proteins present in biological medium. The results showed that the presence of glutamic acid; Glu (acidic amino acids) and arginine; Arg (basic amino acids) on the HA surface resulted in higher protein adsorption owing to stronger electrostatic attraction between the HA particles and the proteins in medium. Functionalizing HA with Glu and Arg significantly promoted osteoblast adhesion on the surface of treated HA. No significant differences in cell proliferation between negatively and positively charged HA was observed. Significantly higher alkaline phosphatase (ALP) activity of osteoblasts on both charged surfaces was seen as compared to the unmodified HA. The study demonstrated that immobilization of amino acids (Glu and Arg) on the surface of HA promoted osteoblast proliferation and ALP activity. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 2150–2160, 2015.
A Green Strategy to Prepare Warfarin‐like Compounds Catalyzed by Zirconium Oxychloride
Authors: Khodabakhshi Saeed , Abbasabadi Masoud Khaleghi , Baghrnejad Mojtaba , Marahel Farzaneh
Published: October 2014

A one‐pot, three‐component synthesis of warfarin‐like compounds from the reaction of benzamide, aryl glyoxal and 4‐hydroxycoumarin is described. Zirconium oxychloride octahydrate catalyzed the reactions efficiently under solvent‐free conditions to yield desired products in good yields.
Single‐step simultaneous side‐by‐side placement of a self‐expandable metallic stent with a 6‐Fr delivery system for unresectable malignant hilar biliary obstruction: a feasibility study
Authors: Kawakubo Kazumichi , Kawakami Hiroshi , Kuwatani Masaki , Kudo Taiki , Abe Yoko , Kawahata Shuhei , Kubo Kimitoshi , Kubota Yoshimasa , Sakamoto Naoya
Published: October 2014

Background

Bilateral self‐expandable metallic stent (SEMS) placement for the management of unresectable malignant hilar biliary obstruction (UMHBO) is technically challenging to perform using the existing metallic stents with thick delivery systems. The recently developed 6‐Fr delivery systems could facilitate a single‐step simultaneous side‐by‐side placement through the accessory channel of the duodenoscope. The aim of this study was to evaluate the feasibility of this procedure.

Methods

Between May and September 2013, 13 consecutive patients with UMHBO underwent a single‐step simultaneous side‐by‐side placement of SEMS with the 6‐Fr delivery system. The technical success rate, stent patency, and rate of complications were evaluated from the prospectively collected database.

Results

Technical success was achieved in 11 (84.6%, 95% confidence interval [CI]: 57.8–95.8) patients. The median procedure time was 25 min. Early and late complications were observed in 23% (one segmental cholangitis and two liver abscesses) and 15% (one segmental cholangitis and one cholecystitis) patients, respectively. Median dysfunction free patency was 263 days (95% CI: 37–263). Five patients (38%) experienced stent occlusion that was successfully managed by endoscopic stent placement.

Conclusions

A single‐step simultaneous side‐by‐side placement of SEMS with a 6‐Fr delivery system was feasible for the management of UMHBO.
The effect of surface treatment and topography on corrosion behavior of EN 1.4404 stainless steel
Authors: Lage R. , Møller P. , Fallesen H. E.
Published: October 2014

Corrosion properties of EN 1.4404 (316L) stainless steel with different applied surface treatment, were studied in NaCl solution using cyclic polarization. Observed properties were related to the specific topography of each surface by scanning electron microcopy and cross‐section analysis. Average roughness was measured to evaluate the usability for this parameter to be used in assessment of corrosion resistance. Increased surface roughness and the existence of crevices resulted in overall deterioration of corrosion resistance, whereas more smooth and level topographies displayed general improvement. By analyzing the characteristic geometry of the typographies produced, the correlation between the varying corrosion properties and surfaces is determinable. In continuation hereof, the utilization of average roughness values (Ra) as an isolated parameter, were found not to be sufficient for the assessment of corrosion resistance. Critical surface geometries with large impact on corrosion properties is not conveyed adequately by Ra, and thereby prevents sufficient differentiation between the actual surface properties.
Inclined stress corrosion cracks in gas pipeline steels: morphology and implications
Authors: Zadow L. , Gamboa E. , Lavigne O.
Published: October 2014

A systematic morphological survey was carried out on 120 stress corrosion cracks (SCC) from an ex service X65 Australian gas pipeline. Out of these cracks, 81% showed a tendency to grow into the material away from the perpendicular. The inclined crack path was suggested to be due to anisotropic residual stress/strains present in the material introduced during pipe manufacturing processes. The overall depth of inclined SCC cracks was found to follow a logarithmic relationship to the SCC surface crack length. Hoop travel was defined as the distance that the crack tip travels in the pipe hoop direction as it grows into the material. The specific hoop travel distance was found to follow a linear relationship as a function of the SCC surface crack length. The relationships between surface crack length to through‐wall crack depth and hoop travel could allow pipe operators to formulate a worst case scenario for the purposes of SCC assessment and management.
Oxidation behavior of chromium‐rich Fe‐based alloys containing HfC carbides at 1100 °C
Authors: Conrath E. , Berthod P.
Published: October 2014

Three HfC‐containing iron‐based alloys were successfully elaborated by foundry. The alloys, all containing 27 wt% Cr, 0.25 or 0.50 wt% C and 4 to 6 wt% Hf, are composed of a dendritic matrix and of HfC carbides of two types: pre‐eutectic blocky carbides and interdendritic script‐like HfC carbides. These alloys were subjected to thermogravimetry tests in air at 1100 °C for 46 h. The presence of hafnium led to oxidation kinetics globally parabolic and low mass gain rates, by comparison with similar Hf‐free ternary alloys. The scales formed all over the samples' surfaces were never composed exclusively of chromia. Iron oxides or (iron, chromium) oxides were also present. Some particles of hafnium oxides were noticed in the subsurface and in the external scales. These particles obviously pegged the external oxide scale on the alloy surface. The long exposure at this high temperature did not significantly modify the characteristics of the bulk HfC carbides. For the alloys in which they were present in the as‐cast state, the eutectic chromium carbides played an important role. They dissolved and helped to supply chromium by enriching the interdendritic spaces which act as fast diffusion paths. In the alloy containing 0.50 wt% Cr and 4 wt% Hf, a parabolic constant of only 2.5 ×10−10 g2 × cm−4 × s−1 was thus obtained, which is a very low value for 1100 °C.
Spinal muscular atrophy: Diagnosis and management in a new therapeutic era
Authors: Arnold W. David , Kassar Darine , Kissel John T.
Published: October 2014

Spinal muscular atrophy (SMA) describes a group of disorders associated with spinal motor neuron loss. In this review we provide an update regarding the most common form of SMA, proximal or 5q‐SMA, and discuss the contemporary approach to diagnosis and treatment. Electromyography and muscle biopsy features of denervation were once the basis for diagnosis, but molecular testing for homozygous deletion or mutation of theSMN1gene allows efficient and specific diagnosis. In combination with loss ofSMN1, patients retain variable numbers of copies of a second similar gene,SMN2, which produces reduced levels of the survival motor neuron (SMN) protein that are insufficient for normal motor neuron function. Despite the fact that understanding of how ubiquitous reduction of SMN protein leads to motor neuron loss remains incomplete, several promising therapeutics are now being tested in early‐phase clinical trials. Muscle Nerve51: 157–167, 2015
Lambs to the Slaughter: A Zooarchaeological Investigation of Stone Circles in Mongolia
Authors: Broderick L. G. , Seitsonen O. , Bayarsaikhan J. , Houle J.‐L.
Published: October 2014

Stone circles are a common monumental feature of the Mongolian Bronze Age (c. 1500–800BC), frequently occurring in association with other monument types, especially khirigsuurs. Until now the content of the stone circles has not been identified, a fact which has hampered our understanding not only of khirigsuurs and their related cosmology but also of the contemporary economy, owing to a research paradigm that was monument‐focused until very recently. The identification of domestic bovids in these features thus has profound implications for our approach to studying the society of this period and region. These implications, including a well‐developed cosmology and economy which included the ritual sacrifice of at least three different kinds of livestock, are introduced here. Copyright © 2014 John Wiley & Sons, Ltd.
Why pediatric patients with cancer visit the emergency department: United States, 2006–2010
Authors: Mueller Emily L. , Sabbatini Amber , Gebremariam Achamyeleh , Mody Rajen , Sung Lillian , Macy Michelle L.
Published: October 2014

Background

Little is known about emergency department (ED) use among pediatric patients with cancer. We explored reasons prompting ED visits and factors associated with hospital admission.

Procedure

A retrospective cohort analysis of pediatric ED visits from 2006 to 2010 using the Nationwide Emergency Department Sample, the largest all‐payer database of United States ED visits. Pediatric patients with cancer (ages ≤19 years) were identified using Clinical Classification Software. Proportion of visits and disposition for the top ten‐ranking non‐cancer diagnoses were determined. Weighted multivariate logistic regression was performed to analyze factors associated with admission versus discharge.

Results

There were 294,289 ED visits by pediatric patients with cancer in the U.S. over the study period. Fever and fever with neutropenia (FN) were the two most common diagnoses, accounting for almost 20% of visits. Forty‐four percent of pediatric patients with cancer were admitted to the same hospital, with admission rates up to 82% for FN. Risk factors for admission were: FN (odds ratio (OR) 8.58; 95% confidence interval (CI) 5.97–12.34); neutropenia alone (OR 7.28; 95% CI 5.08–10.43), ages 0–4 years compared with 15–19 years (OR 1.19; 95% CI 1.08–1.31) and highest median household income ZIP code (OR 1.27; 95% CI 1.08–1.49) compared with lowest. “Self‐pay” visits had lower odds of admission (OR 0.42; 95% CI 0.35–0.51) compared with public payer.

Conclusion

FN was the most common reason for ED visits among pediatric patients with cancer and is the condition most strongly associated with admission. Socioeconomic factors appear to influence ED disposition for this population. Pediatr Blood Cancer 2015;62:490–495. © 2014 Wiley Periodicals, Inc.
Ovarian function in survivors of childhood medulloblastoma: Impact of reduced dose craniospinal irradiation and high‐dose chemotherapy with autologous stem cell rescue
Authors: Balachandar Sadana , Dunkel Ira J. , Khakoo Yasmin , Wolden Suzanne , Allen Jeffrey , Sklar Charles A.
Published: October 2014

Background

Data on ovarian function (OvF) in medulloblastoma (MB) survivors is limited, with most studies describing outcomes in survivors treated with craniospinal irradiation (CSI) doses >24 Gy ± standard chemotherapy. The objective of the current study is to report on OvF: (i) across a range of CSI doses; and (ii) following high‐dose chemotherapy with autologous stem cell rescue (ASCR).

Procedure

Retrospective review of female MB survivors who were diagnosed in childhood and followed at Memorial Sloan Kettering Cancer Center. Patients were divided into three groups: (i) CSI ≤24 Gy +/− standard chemotherapy; (ii) CSI ≥35 Gy +/− standard chemotherapy; and (iii) high‐dose chemotherapy with ASCR +/− CSI.

Results

Primary ovarian dysfunction (POD) occurred in 2/17 subjects in group 1, 3/9 subjects in group 2 and 5/5 subjects in group 3 (P < 0.01). Normalization of function was noted in four subjects with POD. Persistent POD requiring hormone replacement (POF) was observed in 1/17 subjects in group 1, 2/9 in group 2, and 3/5 in group 3 (P = 0.02). Neither age at treatment nor type of standard chemotherapy correlated with risk of POD or POF.

Conclusions

Both POD and POF appear to occur in a small proportion of patients who are treated with contemporary doses of CSI +/− standard chemotherapy. However, ovarian dysfunction requiring hormone replacement therapy is common following high‐dose chemotherapy associated with ASCR. These findings will assist clinicians in counseling patients regarding fertility preservation and risk of impaired ovarian function/future fertility. Pediatr Blood Cancer 2015;62:317–321. © 2014 Wiley Periodicals, Inc.
First trimester screening for early and late preeclampsia based on maternal characteristics, biophysical parameters, and angiogenic factors
Authors: Crovetto Francesca , Figueras Francesc , Triunfo Stefania , Crispi Fatima , Rodriguez‐Sureda Victor , Dominguez Carmen , Llurba Elisa , Gratacós Eduard
Published: October 2014

Objective

The aim of this article is to develop the best first‐trimester screening model for preeclampsia (PE) based on maternal characteristics, biophysical parameters, and angiogenic factors in a low‐risk population.

Methods

A prospective cohort of 9462 pregnancies undergoing first‐trimester screening is used. Logistic regression predictive models were developed for early and late PE (cut‐off of 34 weeks' gestation at delivery). Data included the a priori risk (maternal characteristics), mean arterial pressure (MAP), and uterine artery (UtA) Doppler (11–13 weeks) in all cases. Plasma levels (8–11 weeks) of human chorionic gonadotrophin, pregnancy‐associated plasma protein A, placental growth factor (PlGF), and soluble Fms‐like tyrosine kinase‐1 (sFlt‐1) were analyzed using a nested case–control study design.

Results

The best model for early PE (n = 57, 0.6%) included a priori risk, MAP, UtA Doppler, PlGF, and sFlt‐1 achieving detection rates of 87.7% and 91.2% for 5% and 10% false‐positive rates, respectively (AUC: 0.98 [95% CI: 0.97–0.99]). For late PE (n = 246, 2.6%), the best model included the a priori risk, MAP, UtA Doppler, PlGF, and sFlt‐1 achieving detection rates of 68.3% and 76.4% at 5% and 10% of false‐positive rates, respectively (AUC: 0.87 [95% CI: 0.84–0.90]).

Conclusion

Preeclampsia can be predicted with high accuracy in general obstetric populations with a low risk for PE, by combined algorithms. Angiogenic factors substantially improved the prediction. © 2014 John Wiley & Sons, Ltd.