bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Ligand Structure on MnO Nanoparticles for Enhanced T1 Magnetic Resonance Imaging of Inflammatory Macrophages
Authors: Park Joseph , Bang Doyeon , Kim Eunjung , Yang Jaemoon , Lim Eun‐Kyung , Choi Jihye , Kang Byunghoon , Suh Jin‐Suck , Park Hyo Seon , Huh Yong‐Min , Haam Seungjoo 
Published: October 2012

AbstractCarboxymethyl‐dextran (CM‐dextran) replaced the hydrophobic oleylamine ligands on the surfaces of MnO nanoparticles, rendering them highly water‐soluble by allowing direct contact with excited water protons. Solution MRI studies of the two types of nanoparticles, exchanged and bilayered, with different core sizes have shown that the exchanged ligand structure exhibits significantly enhanced longitudinal relaxation. The modification with dextran converted the nanoparticles into effective T1 MRI contrast agents, as well as promoting strong interactions with macrophages. Thus, it is a potential MR contrast agent for visualizing inflammatory macrophages.
(E,E)‐1,2,3,4‐Tetracyclopropylbuta‐1,3‐diene: Synthesis and Some of Its Properties
Authors: de Meijere Armin , Redlich Stefan , Kozhushkov Sergei I. , Yufit Dmitry S. , Magull Jörg , Vidović Denis , Schill Heiko , Menzel Henning 
Published: October 2012

Abstract(E,E)‐1,2,3,4‐Tetracyclopropylbuta‐1,3‐diene (3) and (Z,Z)‐1,4‐diodo‐1,2,3,4‐tetracyclopropylbuta‐1,3‐diene (4) were prepared from dicyclopropylacetylene via an intermediate 2,3,4,5‐tetracyclopropyltitanacyclopentadiene (2) in 91 and 77 % yield, respectively. In the crystal, 3 adopts a conformation with an almost coplanar (φ = 163°) 1,3‐diene core, with the inner vinylcyclopropane units in an orthogonal and the outer vinylcyclopropane moieties in an s‐trans orientation. This diene, like 2,3‐cyclopropylbuta‐1,3‐diene (5), undergoes facile concerted [4+2] cycloadditions at 130 °C with dimethyl acetylenedicarboxylate as well as N‐phenylmaleimide and at 0 °C with N‐phenyltriazolinedione. An X‐ray crystal structure analysis of 2,3‐dicyclopropylbuta‐1,3‐diene (5) also reveals a coplanar inner core with the vinylcyclopropane units in essentially orthogonal (φav = 89.3°) orientation. Differential scanning calorimetry (DSC) measurements indicate that 3 undergoes significant internal reorganization on going from the liquid to the crystalline phase, and a gauche conformer of 3 may well be favored over the s‐trans conformer in the liquid.
Acetamide as Cocatalyst for the Nitrogen‐Directed Coupling of Arenes with Aryl Chlorides through Ruthenium‐Catalyzed C–H Activation
Authors: Zhang Jie , Yang Qin , Zhu Zhu , Yuan Mao Lin , Fu Hai Yan , Zheng Xue Li , Chen Hua , Li Rui Xiang 
Published: October 2012

AbstractA simple and highly efficient method for the cross‐coupling of aromatics by C–H activation is described. Acetamide was found to be an effective cocatalyst for this generally applicable ruthenium(II)‐catalyzed direct arylation reaction. A wide range of deactivated aryl chlorides could be efficiently coupled under the mild temperature of 101 °C. The new process is highly atom‐economical and sustainable.
Synthesis of the AB‐Ring Pyranolactone Substructure of Granaticin A
Authors: Bartholomäus Ruben , Bachmann Janina , Mang Christian , Haustedt Lars Ole , Harms Klaus , Koert Ulrich 
Published: October 2012

AbstractA synthesis of the AB‐ring substructure of granaticin A was developed. The pyranolactone moiety was stereoselectively accessed by Sharpless asymmetric dihydroxylation and subsequent oxa‐Pictet–Spengler cyclization. The use of BF3·OEt2 resulted in the formation of the cis pyranolactone, whereas the combination of BF3·OEt2 with trifluoroacetic acid led to the trans isomer. The resulting hydroquinones were cleaved selectively by ozonolysis to dicarboxylic acids. An aryl Grignard reagent could be regioselectively added to unsymmetrical anhydrides. As an alternative strategy for the construction of the B‐ring, a benzyne–furan cycloaddition could be established.
A Novel Neutral Carrier for Uranyl Ion Based on a Commercially Available Aminophosphate Derivative: Evaluation in Membrane Electrodes and Nuclear Safeguards Applications
Authors: Badr Ibrahim H. A. , Zidan W. I. , Akl Z. F. 
Published: October 2012

AbstractThe construction and performance characteristics of uranyl membrane electrodes based on cheap and commercially available amino(trimethyl)phosphate are described. The influence of various membrane constituents on the potentiometric responses of the prepared membrane electrodes has been studied. Optimized membrane electrodes exhibited performance characteristics comparable with those based on high cost and commercially available ionophores. Selectivity studies indicated that the developed membrane electrodes are selective towards uranyl ion over a large number of cations including the well‐known uranyl ion interferents (e.g., Fe3+, Th+4). The analytical utility of the proposed membrane electrode has been demonstrated through its application in nuclear safeguards verification purposes.
Performance spectra based method for the seismic design of structures equipped with passive supplemental damping systems
Authors: Guo Jack Wen Wei , Christopoulos Constantin 
Published: October 2012

SUMMARYA new direct performance‐based design method utilizing design tools called performance‐spectra (P‐Spectra) for low‐rise to medium‐rise frame structures incorporating supplemental damping devices is presented. P‐Spectra are graphic tools that relate the responses of nonlinear SDOF systems with supplemental dampers to various damping parameters and dynamic system properties that structural designers can control. These tools integrate multiple response quantities that are important to the performance of a structure into a single compact graphical format to facilitate direct comparison of different potential solutions that satisfy a set of predetermined performance objectives under various levels of seismic hazard. An SDOF to MDOF transformation procedure that defines the required supplemental damping properties for the MDOF structure to achieve the response defined by the target SDOF system is also presented for hysteretic, linear viscous and viscoelastic damping devices. Using nonlinear time‐history analyses of idealized shear structures, the accuracy of the transformation procedure is verified. A seismic performance upgrade design example is presented to demonstrate the usefulness of the proposed method for achieving design performance goals using supplemental damping devices. Copyright © 2012 John Wiley & Sons, Ltd.
Research on mobility handover for IPv6‐based MANET
Authors: Xiaonan Wang , Shan Zhong 
Published: October 2012

ABSTRACTThe paper proposes a mobility handover scheme for IPv6‐based mobile ad hoc network (MANET) Mobility Handover (IMMH). In IMMH, when a node moves out of the communication scope of its upstream node, it is the node that directly establishes the routing path reaching to the upstream node in the Unicast way, which reduces the mobility handover cost and shortens the mobility handover delay. In mobile ad‐hoc networks without any infrastructures, a user always uses a node's home address to communicate with the node, and both the node's mobility handover process and its care‐of address update process are transparent to the user. Therefore, the communication continuity is ensured. From both the theoretical perspective and the simulative perspective, the paper analyzes the performance parameters of IMMH, including the mobility handover cost and the mobility handover delay. The data results show that the mobility handover cost of IMMH is lower and the delay is shorter.Copyright © 2012 John Wiley & Sons, Ltd.
Effects of agriculture production systems on nitrate and nitrite accumulation on baby‐leaf salads
Authors: Aires Alfredo , Carvalho Rosa , Rosa Eduardo A. S. , Saavedra Maria J. 
Published: October 2012

AbstractNitrate and nitrite are widespread contaminants of vegetables, fruits, and waters. The levels of these compounds are increased as a result of using organic wastes from chemical industries, domestic wastes, effluents, nitrogenous fertilizers, and herbicides in agriculture. Therefore, determining the nitrate and nitrite levels in biological, food, and environmental samples is important to protect human health and the environment. In this context, we set this study, in which we report the effect of production system (conventional and organic) on the accumulation of nitrates and nitrites in fresh baby‐leaf samples. The average levels of the nitrate (NO3−) and nitrite (NO2−) contents in six different baby‐leaf salads of a single species (green lettuce, red lettuce, watercress, rucola, chard, and corn salad) produced in organic and conventional agriculture system were evaluated. Spectrophotometric analytical method recently published was validated and used. Nitrates and nitrites were detected in all samples. The nitrates levels from organic production varied between 1.45 and 6.40 mg/kg fresh weight (FW), whereas those from conventional production ranged from 10.5 to 45.19 mg/kg FW. The nitrites content was lower than nitrates and ranged from 0.32 to 1.89 mg/kg FW in organic production system and between 0.14 and 1.41 mg/kg FW in conventional production system. Our results showed that the nitrate content was dependent on the agricultural production system, while for nitrites, this dependency was less pronounced.
Physico‐chemical and sensory properties of cookies made from blends of germinated pigeon pea, fermented sorghum, and cocoyam flours
Authors: Okpala Laura , Okoli Eric , Udensi Emelem 
Published: October 2012

AbstractCookies were produced from germinated pigeon pea, fermented sorghum, and cocoyam flour (CF) blends to determine their potentials in cookie manufacture. Ten flour formulations were produced and they were evaluated for their proximate and functional properties. Protein content ranged from 4.85% to 19.89% with 100% CF (100CF) having the least value, while 100% germinated pigeon pea flour (100GPF) had the highest value. Increase in levels of GPF to the flour blends resulted in increase in protein content of the blends. Cookies made with 100% fermented sorghum flour (100FSF) had the highest ash content of 2.73%, while cookies made with 100GPF had the least ash content. Energy values of the cookies ranged between 369.37 and 376.56 kcal/100 g, with cookie formulation 50%CF:50%FSF having the least value and cookies made with 16.7%CF:16.7%FSF:66.6GPF having the highest value. The control (cookies made with wheat) had the highest spread ratio of 24.13, while cookies made with 100FSF had the least spread ratio of 14.97. Cookies made with 100CF were the least fragile. Sensory ratings revealed that cookies containing up to 50% CF and above, compared favorably with those made with wheat flour.
Supplementing long‐chain n‐3 polyunsaturated fatty acids in canned wild Pacific pink salmon with Alaska salmon oil
Authors: Lapis Trina J. , Oliveira Alexandra C. M. , Crapo Charles A. , Himelbloom Brian , Bechtel Peter J. , Long Kristy A. 
Published: October 2012

AbstractEstablishing n‐3 polyunsaturated fatty acid contents in canned wild Alaska pink salmon products is challenging due to ample natural variation found in lipid content of pink salmon muscle. This study investigated the effect of adding salmon oil (SO) to canned pink salmon produced from fish exhibiting two opposite degrees of skin watermarking, bright (B) and dark (D). Specific goals of the study were to evaluate the benefits of adding SO to canned pink salmon with regard to nutritional value of the product, sensory characteristics, and the oxidative and hydrolytic stability of the lipids over thermal processing. Six groups of canned pink salmon were produced with variable levels of SO, either using bright (with 0, 1, or 2% SO) or dark (with 0, 2, or 4% SO) pink salmon. Compositional analysis revealed highest (P < 0.05) lipid content in sample B2 (8.7%) and lowest (P < 0.05) lipid content in sample D0 (3.5%). Lipid content of samples B0, B1, D2, and D4 was not significantly different (P > 0.05) ranging from 5.7% to 6.8%. Consequently, addition of SO to canned pink salmon allowed for consistent lipid content between bright and dark fish. Addition of 1% or 2% SO to canned bright pink salmon was not detrimental to the sensory properties of the product. It is recommended that canned bright pink salmon be supplemented with at least 1% SO, while supplementation with 2% SO would guarantee a minimum quantity of 1.9 g of n‐3 fatty acids per 100 g of product. Addition of 4% SO to canned dark pink salmon was detrimental to product texture and taste, while supplementation with 2% SO did not negatively affect sensorial properties of the product. Accordingly, canned dark pink salmon should be supplemented with 2% SO so that a minimum n‐3 fatty acids content of 1.5 g per 100 g of product.
Comparative lethality kinetic curves and predictive models of F‐value for Listeria monocytogenes using different sanitizers
Authors: Beltrame Cezar A. , Kubiak Gabriela B. , Rottava Ieda , Toniazzo Geciane , Cansian Rogério L. , Lerin Lindomar A. , de Oliveira Débora , Treichel Helen 
Published: October 2012

AbstractThe objective of this work was to evaluate the kinetic of inactivation of Listeria monocytogenes using peracetic acid, chlorhexidine, and organic acids as active agent, determining the respective D‐, Z‐, and F‐values. From our knowledge, these important results from an industrial view point are not available in the current literature, mainly for organic acids, pointing out the main contribution of the present work. Lower D‐values were obtained for peracetic acid and chlorhexidine, compared with the organic acids. For the reduction of 6 log10 of L. monocytogenes using peracetic acid, at 0.2, 0.1, and 0.05% are necessary 7.08, 31.08, and 130.44 min of contact, respectively. The mathematical models of F‐values showed that at concentrations lower than 0.15% one can verify an exponential increase in F‐values, for both de chlorhexidine and peracetic acid. The organic acids presented a linear behavior, showing slight variation in F‐values, is even more effective in under dosage. The results obtained are of fundamental importance in terms of industrial strategy for sanitization procedure, permitting to choose the best relation product concentration/exposure time, aiming at reducing costs without compromising the disinfectant efficiency.
Inhibitory effects of tert‐butylhydroquinone on osteoclast differentiation via up‐regulation of heme oxygenase‐1 and down‐regulation of HMGB1 release and NFATc1 expression
Authors: Yamaguchi Yu , Sakai Eiko , Sakamoto Hiroshi , Fumimoto Reiko , Fukuma Yutaka , Nishishita Kazuhisa , Okamoto Kuniaki , Tsukuba Takayuki 
Published: October 2012

ABSTRACTOsteoclasts (OCLs) are multinucleated bone‐resorbing cells that are differentiated by receptor activator of nuclear factor kappa‐B ligand (RANKL) and macrophage colony‐stimulating factor (M‐CSF). Our recent studies have shown that heme‐oxygenase‐1 (HO‐1), a stress‐induced cytoprotective enzyme, plays an important role in OCL differentiation, although the pharmacological significance of this effect remains unknown. In this study, we investigated the effects of tert‐butylhydroquinone (tBHQ), a pharmacological HO‐1 inducer, on in vitro differentiation of bone marrow‐derived macrophages (BMMs) or murine monocytic cell line RAW‐D into OCLs. tBHQ inhibited the formation and the bone‐resorbing activity of OCLs. Moreover, tBHQ treatment decreased the expression of nuclear factor of activated T cells cytoplasmic‐1 (NFATc1), a master regulator of OCL differentiation, and of OCL markers transcriptionally regulated by NFATc1, such as Src and cathepsin K. In addition, tBHQ impaired phosphorylation of extracellular signal‐regulated kinase, p38 mitogen‐activated protein kinase (MAPK), Jun N‐terminal kinase, Akt, and inhibitor of nuclear factor kappa B alpha (IκBα). Finally, we show that tBHQ inhibited the release of high mobility group box 1 (HMGB1), a recently identified activator of OCL differentiation. Thus, tBHQ inhibits OCL differentiation through the HO‐1/HMGB1 pathways. Copyright © 2012 John Wiley & Sons, Ltd.
Reaction of Phthalaldehyde with Aminoethanol under Different Conditions: Products and Mechanisms of Their Formation
Authors: Klíma Jiří , Polášek Miroslav , Ludvík Jiří , Urban Jiří 
Published: October 2012

Analysis of amino acids and very efficient disinfection procedures are based on the reaction of phthalaldehyde (OPA) with primary amines. In this contribution, aminoethanol (=kolamin) as a nitrogen‐containing nucleophile was used for the investigation of its reaction mechanism with OPA performed in basic aqueous buffered media (pH 9.5), where an influence of hydration or solvation is expected, and in anhydrous acetonitrile. Depending on the detailed reaction conditions, seven products were isolated and their structures determined by NMR, mass spectrometry, and X‐ray structure analysis. Reaction mechanisms are proposed, which involve hydride transfers to OPA (Cannizzaro‐type reaction).
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On the Nature of the Causal Relationships Between Foreign Direct Investment, GDP and Exports in South Africa
Authors: Akoto William 
Published: October 2012

AbstractWhat started as a financial crisis in 2008–2009 quickly became a crisis of trade for many emerging economies. Using South Africa as a case study, this paper examines the Granger causal relationships between foreign direct investment (FDI), exports and GDP as well as the responsiveness of exports to FDI shocks. The findings indicate that in the long run, FDI has a significant impact on boosting exports. In the short run, there is bi‐directional Granger causality between GDP and exports, with uni‐directional causality from FDI to exports and FDI to GDP. However, variance decomposition analyses shows that exports are not very responsive to changes in FDI inflow. Copyright © 2012 John Wiley & Sons, Ltd.
Rationally Designed α‐Helical Broad‐Spectrum Antimicrobial Peptides with Idealized Facial Amphiphilicity
Authors: Wiradharma Nikken , Sng Melvin Y. S. , Khan Majad , Ong Zhan‐Yuin , Yang Yi‐Yan 
Published: October 2012

AbstractA series of 12‐amino acid peptide analogs is designed using point mutation strategy based on an α‐helical peptide template. The first mutation in the series, KL12, has an idealized facial amphiphilicity. Subsequent mutations are performed to increase hydrophobic or cationic contents. Idealized facial amphiphilicity show enhanced antimicrobial activity and selectivity against most of the tested microbes. Increasing hydrophobic contents further enhance antimicrobial potency; however, selectivity of the most hydrophobic analog is impaired due to non‐specific interactions with mammalian cell membrane. This study demonstrates that facial amphiphilicity and hydrophobic content are strongly correlated with antimicrobial activity and selectivity of antimicrobial peptides.
Low dietary folate and methylenetetrahydrofolate reductase deficiency may lead to pregnancy complications through modulation of ApoAI and IFN‐γ in spleen and placenta, and through reduction of methylation potential
Authors: Mikael Leonie G. , Pancer Jill , Jiang Xinyin , Wu Qing , Caudill Marie , Rozen Rima 
Published: October 2012

ScopeGenetic or nutritional disturbances in folate metabolism lead to hyperhomocysteinemia and adverse reproductive outcomes. Folate‐dependent homocysteine remethylation is required for methylation reactions and may influence choline/betaine metabolism. Hyperhomocysteinemia has been suggested to play a role in inflammation. The goal of this study was to determine whether folate‐related pregnancy complications could be due to altered expression of some inflammatory mediators or due to disturbances in methylation intermediates.Methods and resultsPregnant mice with or without a deficiency of methylenetetrahydrofolate reductase (MTHFR) were fed control diets or folate‐deficient (FD) diets; tissues were collected at embryonic day 14.5. FD decreased plasma phosphocholine and increased plasma glycerophosphocholine and lysophosphatidylcholine. Liver betaine, phosphocholine, and S‐adenosylmethionine:S‐adenosylhomocysteine ratios were reduced in FD. In liver, spleen, and placenta, the lowest levels of apolipoprotein AI (ApoAI) were observed in Mthfr+/– mice fed FD. Increased interferon‐gamma (IFN‐γ) was observed in spleen and placentae due to FD or Mthfr genotype. Plasma homocysteine correlated negatively with liver and spleen ApoAI, and positively with IFN‐γ.ConclusionLow dietary folate or Mthfr deficiency during pregnancy may result in adverse pregnancy outcomes by altering expression of the inflammatory mediators ApoAI and IFN‐γ in spleen and placenta. Disturbances in choline metabolism or methylation reactions may also play a role.
Living Anionic Polymerization of tert‐Butyl Acrylate in a Flow Microreactor System and Its Applications to the Synthesis of Block Copolymers
Authors: Nagaki Aiichiro , Takahashi Yusuke , Akahori Kana , Yoshida Jun‐ichi 
Published: October 2012

AbstractLiving anionic polymerization of tert‐butyl acrylate initiated by 1,1‐diphenylhexyllithium is conducted in a flow microreactor system in the presence of lithium chloride. A high degree of control over the molecular weight distribution is achieved under easily accessible conditions, for example at −20 °C. The subsequent reaction of a reactive polymer chain end with an alkyl methacrylate in an integrated flow micoreactor system leads to the formation of a block copolymer with a narrow molecular weight distribution. magnified image
Understanding Entheseal Changes: Definition and Life Course Changes
Authors: Villotte S. , Knüsel C. J. 
Published: October 2012

ABSTRACTOver the past two decades, many articles have been published on entheseal changes (usually called ‘Musculoskeletal Stress Markers’) as activity markers in past societies. Over‐simplified methods and over‐interpretation of past activities have generated strong critiques of research results in this area of enquiry. While some significant improvements regarding the recording systems for entheseal changes have been applied more recently, many bioarchaeologists appear not yet to be fully aware of the multi‐factorial aetiology of these alterations. In this article, we review the anatomical and clinical literature to discuss some of the difficulties associated with the recording of entheseal changes and the multiple factors leading to their appearance in the human skeleton. Thus far, fibrocartilaginous entheses appear to hold more promise for activity‐related reconstruction than do fibrous ones, but these relationships remain an area of active research interest. Copyright © 2012 John Wiley & Sons, Ltd.