bluuebunny/crossref_metadata_2025 huggingface dataset:
A Unified Approach to Local Cohomology Modules using Serre Classes
Authors: Asgharzadeh Mohsen , Tousi Massoud
Published: July 2010

This paper discusses the connection between the local cohomology modules and the Serre classes of R-modules. This connection has provided a common language for expressing some results regarding the local cohomology R-modules that have appeared in different papers.
Multiple Solutions for a Class of Neumann Elliptic Problems on Compact Riemannian Manifolds with Boundary
Authors: Kristály Alexandru , Papageorgiou Nikolaos S. , Varga Csaba
Published: July 2010

We study a semilinear elliptic problem on a compact Riemannian manifold with boundary, subject to an inhomogeneous Neumann boundary condition. Under various hypotheses on the nonlinear terms, depending on their behaviour in the origin and infinity, we prove multiplicity of solutions by using variational arguments.
Non-Right-Orderable 3-Manifold Groups
Authors: Roberts R. , Shareshian J.
Published: July 2010

We exhibit infinitely many hyperbolic 3-manifold groups that are not right-orderable.
Measures with Fourier Transforms in L2 of a Half-space
Authors: Shayya Bassam
Published: July 2010

We prove that if the Fourier transform of a compactly supported measure is in L2 of a half-space, then the measure is absolutely continuous to Lebesgue measure. We then show how this result can be used to translate information about the dimensionality of a measure and the decay of its Fourier transform into geometric information about its support.
Interval Pattern Avoidance for Arbitrary Root Systems
Authors: Woo Alexander
Published: July 2010

We extend the idea of interval pattern avoidance defined by Yong and the author for Sn to arbitrary Weyl groups using the definition of pattern avoidance due to Billey and Braden, and Billey and Postnikov. We show that, as previously shown by Yong and the author for GLn, interval pattern avoidance is a universal tool for characterizing which Schubert varieties have certain local properties, and where these local properties hold.
Integrated yield and productivity enhancement strategy for biotechnological production of Azadirachtin by suspension culture of Azadirachta indica
Authors: Prakash Gunjan , Srivastava Ashok K.
Published: July 2010

Azadirachtin is considered as the best pesticide among the biopesticides available in market for crop protection due to its broad spectrum activity and varying mode of action. To meet the increasing demand and primarily due to geographical and variability limitations, its biotechnological production from plant cell culture has gained momentum in last two decades. The major requirement for economic production is to increase the yield as well as the productivity of Azadirachtin production in the bioreactor. In general, different strategies used in the plant cell culture result in either yield or productivity enhancement. The simultaneous increase of both the parameters has remained a challenging task, particularly in plant cell cultivations. In this work, an integrated approach has been adopted by combining the various yield as well as productivity enhancement strategies, i.e. coupling the mathematical model–derived nutrient‐feeding strategy for continuous cultivation with elicitation, precursor addition, and permeabilization, etc. With this integrated approach, a yield of 0.0122 g/g and a productivity of 7.25 × 10−4 g/l/h Azadirachtin were obtained, which is so far highest in plant cell suspension culture of Azadirachta indica to the best of our knowledge. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.
Nanoparticles prepared by blending of carboxylic acid terminated poly(ε‐caprolactone) and L‐phenylalanine substituted dextran
Authors: Liu Jiyan , Liu Xueqing
Published: July 2010

Preparation and characterization of nanoparticles from L‐phenylalanine substituted dextrans (Dex‐Phes) and carboxyl‐terminated poly(ε‐caprolactone) (PCL‐COOH) blends in water/dimethyl sulfoxide (DMSO) (10/1, v/v) solution are reported. Dex‐Phe with degree of substitution (DS) = 0.67 has good solubility in both water and DMSO, which can form the nanoparticles with PCL‐COOH in water/DMSO solution. The size and size distribution of the nanoparticles were characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The effect of weight ratio of PCL‐COOH to Dex‐Phes on particle size was investigated. A possible mechanism for the formation of nanoparticles was also proposed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Analyzing and predicting the thermodynamic effects of the metabolite trehalose on nucleic acids
Authors: Hart Jonathan L. , Harris Zachary M. , Testa Stephen M.
Published: July 2010

There is a lot of interest in exactly how nucleic acid duplexes are affected by the addition of certain stabilizing and destabilizing metabolites. Unfortunately, the differences in reaction conditions between published reports often precludes a comparison of the results, effectively preventing a cohesive strategy for predicting additive effects on nucleic acid stability. This information is critically important for obtaining a fundamental understanding of how additives, including metabolites, alter DNA and RNA stability and structure. We now show that the destabilization of nucleic acids by the metabolite trehalose in standard optical melting buffer (20 mM sodium cacodylate, 1M NaCl, and 0.5 mM EDTA) differs from that of a common PCR buffer, and a simulated physiological buffer, with up to an 8°C melting temperature difference. We also demonstrate that the extent of DNA destabilization due to trehalose depends on DNA length and depends on percent GC content, at least for the primer‐length duplexes studied here. Furthermore, we show that glucose (a monomer) is not quite as effective a destabilizer as trehalose (a dimer). The implications of these results related to trehalose‐destabilization of DNA, related to conducting and analyzing DNA‐additive experiments, and related to using this type of data for predictive purposes are discussed. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 1085–1092, 2010.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Magneto–Structural Correlations in Discrete MnII‐WV Cyano‐Bridged Assemblies with Polyimine Ligands
Authors: Podgajny Robert , Korzeniak Tomasz , Przychodzeń Paweł , Gimenez‐Saiz Carlos , Rams Michał , Kwaśniak Michał , Sieklucka Barbara
Published: July 2010

We present the magneto–structural correlations for two novel discrete cyano‐bridged assemblies based on cationic complexes of manganese(II) with diimine ligands and octacyanotungstate(V) ions. The crystal structure of [MnII(terpy)(dmf)(H2O)2][MnII(terpy)(H2O)(dmf)(μ‐NC)WV(CN)7]2·6H2O (1) (terpy = 2,2′;6′,2″‐terpyridine, dmf = dimethylformamide) contains dinuclear {MnIIWV}– cyano‐bridged anions, while the crystal structure of [MnII(phen)3]2[MnII(phen)2(μ‐NC)2WV(CN)6]2(ClO4)2·9H2O (2) (phen = 1,10‐phenanthroline) is built of tetranuclear {MnII2WV2}2– square anions. Intramolecular Mn–W magnetic interactions through the cyano bridges are represented by magnetic coupling constants J = –39 cm–1 for the {MnIIWV}– unit in 1 and J1 = –25.7 and J2 = –16.7 cm–1 for the {MnII2WV2}2– unit in 2. J and J1 represent relatively strong W–CN–Mn interactions and are ascribed to the bridges in b positions of TPRS‐8 (trigonal prism square‐face bicapped) of [W(CN)8]3– polyhedra, favoring the strongest electronic interactions between the d–d orbital of W and the π* orbitals of CN–, whereas J2 is related to the m vertex of [W(CN)8]3–. The magnetic properties of 1 and 2 are compared with reference compounds and discussed in the context of the type of coordination polyhedra of [W(CN)8]3– as well as the metric parameters of cyano‐bridged W–CN–Mn linkages. We found the type of coordination polyhedra and bridging mode of [W(CN)8]3– to be the most important factors influencing the magnitude of the Mn–W magnetic interaction.
From Salicylaldehyde to Chiral Salen Sulfonates – Syntheses, Structures and Properties of New Transition Metal Complexes Derived from Sulfonato Salen Ligands
Authors: Delahaye Émilie , Diop Mayoro , Welter Richard , Boero Mauro , Massobrio Carlo , Rabu Pierre , Rogez Guillaume
Published: July 2010

Coordination complexes derived from chiral and nonchiral sulfonato salen ligands {(SalenSO3)Na2: N,N′‐bis(5‐sulfonatosalicylidene)‐1,2‐diaminoethane disodium salt, [(R,R) and (S,S)‐CySalenSO3]NaK: (R,R) and (S,S)‐N,N′‐bis(5‐sulfonatosalicylidene)‐1,2‐diaminocyclohexane sodium–potassium salt} have been synthesized. The crystal structures of the chiral and nonchiral NiII complexes [Ni(SalenSO3)]Na2 (1) and [Ni((R,R)CySalenSO3)]NaK (2) were solved. The other chiral and nonchiral sulfonato salen complexes, [Cu(SalenSO3)]Na2 (4), [Cu((R,R)CySalenSO3)]NaK (5), [Cu((S,S)CySalenSO3)]NaK (6) and [Zn(SalenSO3)]Na2 (7) got hydrolyzed before suitable crystals could form. Yet, their hydrolysis led to the formation of single crystals of the residues of total or partial hydrolysis: 5‐sulfonatosalicylaldehyde sodium salt (A), N‐(5‐sulfonatosalicylidene)‐1,2‐diaminoethane copper(II) [Cu(SalSO3)] (8) and (R,R)‐N‐(5‐sulfonatosalicylidene)‐1,2‐diaminocyclohexane copper(II) {Cu[(R,R)CySalSO3]} (9). All compounds were studied with IR and UV/Vis spectroscopy; chiral compounds were also investigated by circular dichroism. The magnetic properties of the copper compounds were investigated. Whereas 8 shows intermolecular antiferromagnetic interactions between mononuclear CuII complexes, 7 presents a weak intramolecular ferromagnetic coupling (J = 0.66 cm–1, H = –JŜCu1ŜCu2), which has been rationalized by DFT calculations.
Synthesis of Binaphthyl Sulfonimides and Their Application in the Enantioselective Michael Addition of Ketones to Nitroalkenes
Authors: Ban Shurong , Du Da‐Ming , Liu Han , Yang Wen
Published: July 2010

Novel types of L‐proline‐based binaphthyl sulfonimides and sulfonamides were found to be efficient organocatalysts for the asymmetric Michael addition of ketones to nitroalkenes to provide optically active γ‐nitroketone derivatives of synthetic and biological importance. After the fine optimization of solvents, temperature, and additive, good to excellent enantioselectivities and diastereoselectivities (71–96 % ee, up to >99:1 dr) can be achieved.
Immune thrombocytopenia as a paraneoplastic syndrome in patients with nasopharyngeal cancer
Authors: Yang Kunyu , Zhang Tao , Chen Jing , Fan Li , Yin Zhongyuan , Hu Yu , Wu Gang
Published: July 2010

Background

Nasopharyngeal cancer (NPC) presenting with thrombocytopenia is rare. This report details 2 cases of NPC with grade III thrombocytopenia as a paraneoplastic syndrome.

Methods

We present 2 cases of NPC in whom grade III thrombocytopenia was diagnosed concurrently at presentation. One patient underwent definitive intensity‐modulated radiation therapy (IMRT) in combination with concurrent cetuximab, the other with cisplatin. Both patients received adjuvant chemotherapy composed of docetaxel and cisplatin.

Results

The cause of their grade III thrombocytopenia was diagnosed as immunologic in origin. Prednisone was administered before IMRT, and their peripheral platelet counts recovered to normal levels. Their platelet counts fell below normal levels several times during their treatment. However, their radiotherapy and chemotherapy had never been interrupted due to thrombocytopenia.

Conclusion

Grade III thrombocytopenia is a rare paraneoplastic syndrome in patients with NPC. These patients can tolerate the aggressive definitive management of radiotherapy and chemotherapy with supportive care. © 2010 Wiley Periodicals, Inc. Head Neck, 2012
How to test nontarget effects of veterinary pharmaceutical residues in livestock dung in the field
Authors: Jochmann Ralf , Blanckenhorn Wolf U , Bussière Luc , Eirkson Charles E , Jensen John , Kryger Ute , Lahr Joost , Lumaret Jean-Pierre , Römbke Jörg , Wardhaugh Keith G , Floate Kevin D
Published: July 2010

To register veterinary medicinal products (VMPs) as parasiticides on pastured animals, legislation in the European Union requires an environmental risk assessment to test the potential nontarget effects of fecal residues on dung-dwelling organisms. Products with adverse effects in single-species laboratory tests require further, higher-tier testing to assess the extent of these effects on entire communities of dung-dwelling organisms under more realistic field or semifield conditions. Currently, there are no documents specifically written to assist researchers in conducting higher-tier tests or to assist regulators in interpreting the results of such tests in an appropriate context. Here we provide such a document, written by members of the SETAC Advisory Group DOTTS (Dung Organism Toxicity Testing Standardization) with research experience on dung fauna in central and southern Europe, Canada, Australia, and South Africa. This document briefly reviews the organisms that make up the dung community and their role in dung degradation, identifies key considerations in the design and interpretation of experimental studies, and makes recommendations on how to proceed. Integr Environ Assess Manag 2011;7:287–296. © 2010 SETAC
The Ku‐dependent non‐homologous end‐joining pathway contributes to low‐dose radiation‐stimulated cell survival
Authors: Yu Xiaoyan , Wang Hongyan , Wang Ping , Chen Benjamin P.C. , Wang Ya
Published: July 2010

Low‐dose (≤0.1 Gy) radiation‐induced adaptive responses could protect cells from high‐challenge dose radiation‐induced killing. The protective role is believed to promote the repair of DNA double‐strand breaks (DSBs) that are a severe threat to cell survival. However, it remains unclear which repair pathway, homologous recombination repair (HRR) or non‐homologous end‐joining (NHEJ), is promoted by low‐dose radiation. To address this question, we examined the effects of low‐dose (0.1 Gy) on high‐challenge dose (2–4 Gy) induced killing in NHEJ‐ or HRR‐deficient cell lines. We showed that 0.1 Gy reduced the high‐dose radiation‐induced killing for wild‐type or HRR‐deficient cells, but enhanced the killing for NHEJ‐deficient cells. Interestingly, low‐dose radiation also enhanced the killing for wild‐type cells exposed to high‐challenge dose radiation with high‐linear energy transfer (LET). Because it is known that high‐LET radiation induces an inefficient NHEJ, these results support that the low‐dose radiation‐stimulated protective role in reducing high‐challenge dose (low‐LET)‐induced cell killing might depend on NHEJ. In addition, we showed that low‐dose radiation activated the DNA‐PK catalytic subunit (DNA‐PKcs) and the inhibitor of DNA‐PKcs destroyed the low‐dose radiation‐induced protective role. These results suggest that low‐dose radiation might promote NHEJ through the stimulation of DNA‐PKcs activity and; therefore, increase the resistance of cells to high‐challenge dose radiation‐induced killing. J. Cell. Physiol. 226: 369–374, 2011. © 2010 Wiley‐Liss, Inc.
Highly Air‐Stable Thieno[3,2‐b]thiophene‐Thiophene‐Thiazolo[5,4‐d]thiazole‐Based Polymers for Light‐Emitting Diodes
Authors: Mishra Sarada P. , Palai Akshaya K. , Kumar Amit , Srivastava Ritu , Kamalasanan Modeeparampil N. , Patri Manoranjan
Published: July 2010

A series of highly air‐stable, low‐bandgap poly(3‐alkylthiophene)s containing electron‐rich thieno[3,2‐b]thiophene and electron‐deficient thiazolo[5,4‐d]thiazole rings were synthesized by the Stille coupling reaction. The polymers exhibited good thermal stability and solubility with excellent film forming properties when drop‐ or spin‐cast from solution. A strong absorption at 564–568 nm and a shoulder at 614–616 nm were observed. The optical bandgap of the polymers was found to be 1.82–1.85 eV. The IP of the polymers was found to be 5.62–5.65 eV. All polymers showed strong fluorescent emission both in solution and in the solid state. EL devices were fabricated using the polymers as an emissive layer and red emission was observed with the emission range of 649–679 nm.

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Synthesis and Characterization of a Red‐Emitting Copolymer Containing 5,8‐Quinoline Units
Authors: Liu Zhanpeng , Zhang Juanjuan , Qiu Yurui , Qin Long , Zhang Ping
Published: July 2010

A novel nitrogen‐containing electroluminescent copolymer, PQV‐alt‐MOPPV has been designed and synthesized by Wittig‐Horner polymerization. Structure, thermal stability, and optical and electrochemical properties of the resulting copolymer were characterized by FT‐IR, 1H NMR, elemental analysis, GPC, DSC, TGA, UV‐vis, PL, EL, and CV. The copolymer possesses excellent solubility in common organic solvents and good thermal stability. The absorption maxima of the copolymer in solution and a thin film are 490 and 516 nm, and the photoluminescence maxima in solution and thin film are 571 and 629 nm, respectively. The PLED (ITO/PEDOT: PSS (40 nm)/PQV‐alt‐MOPPV (80 nm)/Ca (30 nm)/Al (150 nm) shows a very pure red light emission with maximum peaks around 618 nm.

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Coping strategies used by children hospitalized with cancer: an exploratory study
Authors: Li H.C. William , Chung Oi Kwan Joyce , Ho Ka Yan Eva , Chiu Sau Ying , Lopez Violeta
Published: July 2010

Objectives: The treatment of cancer is a stressful and threatening experience, particularly for children. Knowing how children cope with cancer is a crucial step toward designing appropriate psychological interventions that help them ease the burden of cancer treatment. The purpose of this study was to examine the coping strategies used by Chinese children hospitalized with cancer, an area of research that is under‐represented in the existing literature.

Methods: Hong Kong Chinese children (9–16‐year olds) admitted for cancer treatment to the pediatric oncology units of two different regional acute public hospitals were invited to participate. A short one‐to‐one structured interview was conducted with each participant. Content analysis was conducted to analyze the interview data.

Results: A convenience sample of 88 children was recruited and participated in the interviews during an 8‐month period. The coping strategies used by Chinese children hospitalized with cancer did not differ according to gender and diagnosis, but only according to age, with younger children using less problem‐focused and more emotion‐focused coping strategies than older children. The overall results indicated that 30% of these Chinese patients used problem‐focused coping strategies, while 70% used emotion‐focused coping.

Conclusions: Findings from this study indicated that children use different coping strategies at different developmental stages. The study also revealed that Chinese children used more emotion‐focused than problem‐focused coping strategies than their Western counterparts. The information derived from this study will help health‐care professionals design and shape appropriate psychological interventions that can help reduce the burden of cancer treatment. Copyright © 2010 John Wiley & Sons, Ltd.
Arraying prostate specific antigen PSA and Fab anti‐PSA using light‐assisted molecular immobilization technology
Authors: Parracino Antonietta , Neves‐Petersen Maria Teresa , di Gennaro Ane Kold , Pettersson Kim , Lövgren Timo , Petersen Steffen B.
Published: July 2010

We here report for the first time the creation of prostate specific antigen (PSA) and Fab anti‐PSA biosensor arrays using UV light‐assisted molecular immobilization (LAMI), aiming at the detection and quantification of PSA, a cancer marker. The technology involves formation of free, reactive thiol groups upon UV excitation of protein aromatic residues located in spatial proximity of disulphide bridges, a conserved structural feature in both PSA and Fab molecules. The created thiol groups bind onto thiol reactive surfaces leading to oriented covalent protein immobilization. Protein activity was confirmed carrying out immunoassays: immobilized PSA was recognized by Fab anti‐PSA in solution and immobilized Fab anti‐PSA cross‐reacted with PSA in solution. LAMI technology proved successful in immobilizing biomedically relevant molecules while preserving their activity, highlighting that insight into how light interacts with biomolecules may lead to new biophotonic technologies. Our work focused on the application of our new engineering principles to the design, analysis, construction, and manipulation of biological systems, and on the discovery and application of new engineering principles inspired by the properties of biological systems.
Neuroprotective and anti‐inflammatory effects of the adenosine A2A receptor antagonist ST1535 in a MPTP mouse model of Parkinson's disease
Authors: Frau Lucia , Borsini Franco , Wardas Jadwiga , Khairnar Amit S. , Schintu Nicoletta , Morelli Micaela
Published: July 2010

Adenosine A2A receptor antagonists are one of the most attractive classes of drug for the treatment of Parkinson's disease (PD) as they are effective in counteracting motor dysfunctions and display neuroprotective and anti‐inflammatory effects in animal models of PD. In this study, we evaluated the neuroprotective and anti‐inflammatory properties of the adenosine A2A receptor antagonist ST1535 in a subchronic 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) mouse model of PD. C57BL/6J mice were repeatedly administered with vehicle, MPTP (20 mg/kg), or MPTP + ST1535 (2 mg/kg). Mice were sacrificed three days after the last administration of MPTP. Immunohistochemistry for tyrosine hydroxylase (TH) and cresyl violet staining were employed to evaluate dopaminergic neuron degeneration in the substantia nigra pars compacta (SNc) and caudate‐putamen (CPu). CD11b and glial fibrillary acidic protein (GFAP) immunoreactivity were, respectively, evaluated as markers of microglial and astroglial response in the SNc and CPu. Stereological analysis for TH revealed a 32% loss of dopaminergic neurons in the SNc after repeated MPTP administration, which was completely prevented by ST1535 coadministration. Similarly, CPu decrease in TH (25%) was prevented by ST1535. MPTP treatment induced an intense gliosis in both the SNc and CPu. ST1535 totally prevented CD11b immunoreactivity in both analyzed areas, but only partially blocked GFAP increase in the SNc and CPu. A2A receptor antagonism is a new opportunity for improving symptomatic PD treatment. With its neuroprotective effect on dopaminergic neuron toxicity induced by MPTP and its antagonism on glial activation, ST1535 represents a new prospect for a disease‐modifying drug. Synapse, 2010. © 2010 Wiley‐Liss, Inc.
Mitochondria in the striatum of subjects with schizophrenia: Relationship to treatment response
Authors: Somerville Shahza M. , Lahti Adrienne C. , Conley Robert R. , Roberts Rosalinda C.
Published: July 2010

Schizophrenia (SZ) is a severe mental illness with neuropathology in many regions, including the striatum. The typical symptoms of this disease are psychosis (such as hallucinations and delusions), cognitive impairments, and the deficit syndrome. Not all patients respond to treatment and, in those who do, only psychotic symptoms are improved. Imaging studies support a biological distinction between treatment response and resistance, but postmortem examinations of this issue are rare. This study tests the hypotheses that abnormalities in mitochondria, the energy producing organelles in the cell, may correlate with treatment response. Postmortem striatal tissue was obtained from the Maryland Brain Collection. The density of mitochondria (in various neuropil compartments) and the number of mitochondria per synapse (all types of synapses combined) were tallied using electron microscopy and stereology in striatum from SZ subjects (rated treatment responsive or not) and normal controls. The number of mitochondria per synapse was significantly different among groups for both the caudate nucleus (P < 0.025) and putamen (P < 0.002). Compared to controls, treatment‐responsive SZ subjects had a 37–43% decrease in the number of mitochondria per synapse in the caudate nucleus and putamen. In the putamen, treatment‐responsive subjects also had decreases in this measure compared to treatment‐resistant subjects (34%). Our results provide further support for a biological distinction between treatment response and treatment resistance in SZ. Because treatment responders have fewer mitochondria per synapse than controls, although the treatment‐resistant subjects have similar results to that of controls, fewer mitochondria per synapse may be related to treatment response. Synapse, 2010. © 2010 Wiley‐Liss, Inc.
Speech perception and production
Authors: Casserly Elizabeth D. , Pisoni David B.
Published: July 2010

Until recently, research in speech perception and speech production has largely focused on the search for psychological and phonetic evidence of discrete, abstract, context‐free symbolic units corresponding to phonological segments or phonemes. Despite this common conceptual goal and intimately related objects of study, however, research in these two domains of speech communication has progressed more or less independently for more than 60 years. In this article, we present an overview of the foundational works and current trends in the two fields, specifically discussing the progress made in both lines of inquiry as well as the basic fundamental issues that neither has been able to resolve satisfactorily so far. We then discuss theoretical models and recent experimental evidence that point to the deep, pervasive connections between speech perception and production. We conclude that although research focusing on each domain individually has been vital in increasing our basic understanding of spoken language processing, the human capacity for speech communication is so complex that gaining a full understanding will not be possible until speech perception and production are conceptually reunited in a joint approach to problems shared by both modes. Copyright © 2010 John Wiley & Sons, Ltd.

This article is categorized under:

Linguistics > Language in Mind and Brain

Psychology > Language
Studies on the Effect of Amino Acids/Peptide on Micellization of SDS at Different Temperatures
Authors: Ali Anwar , Ansari Nizamul Haque
Published: July 2010

Conductivities of (0.001–0.012) m sodium dodecyl sulfate have been determined in water and in the presence of 0.10 m aqueous glycine/alanine/glycylglycine at 298.15, 303.15, 308.15, and 313.15 K. From the specific conductivity data, the critical micellar concentration, degree of counter ion association, degree of counterion dissociation, free energy of transfer of hydrophobic chain from the medium to interior of the micelle, and surface contribution, standard free energy of micellization, standard enthalpy of micellization, and standard entropy of micellization of sodium dodecyl sulfate have been computed. The thermodynamic parameters of micellization and the effect of additives on these parameters have been used to study the interactions present in the micellar systems.
Delhi and CWG2010: The Games Behind the Games
Authors: Menon-Sen Kalyani
Published: July 2010

If Shanghai has the World Expo 2010, Delhi has the Commonwealth Games 2010.
Transition to global instability in transverse-jet shear layers
Authors: DAVITIAN J. , GETSINGER D. , HENDRICKSON C. , KARAGOZIAN A. R.
Published: July 2010

In a recent paper (Megerianet al.,J. Fluid Mech., vol. 593, 2007, pp. 93–129), experimental exploration of the behaviour of transverse-jet near-field shear-layer instabilities suggests a significant change in the character of the instability as jet-to-crossflow velocity ratiosRare reduced below a critical range. The present study provides a detailed exploration of and additional insights into this transition, with quantification of the growth of disturbances at various locations along and about the jet shear layer, frequency tracking and response of the transverse jet to very strong single-mode forcing, creating a ‘lock-in’ response in the shear layer. In all instances, there is clear evidence that the flush transverse jet's near-field shear layer becomes globally unstable whenRlies at or below a critical range near 3. These findings have important implications for and provide the underlying strategy by which active control of the transverse jet may be developed.
On the maximum drag reduction due to added polymers in Poiseuille flow
Authors: WOODCOCK JAMES D. , SADER JOHN E. , MARUSIC IVAN
Published: July 2010

The addition of elastic polymers to turbulent liquids is known to produce significant drag reduction. In this study, we prove that the drag in pipe and channel flows of an unforced laminar fluid constitutes a lower bound for the drag of a fluid containing dilute elastic polymers. Further, the addition of elastic polymers to laminar fluids invariably increases drag. This proof does not rely on the adoption of a particular constitutive equation for the polymer force, and would also be applicable to other similar methods of drag reduction, which are also achieved by the addition of certain particles to a flow. Examples of such methods include the addition of surfactants to a flowing liquid and the presence of sand particles in sandstorms and water droplets in cyclones.
In X. laevis embryos high levels of the anti-apoptotic factor p27BBP/eIF6 are stage-dependently found in BrdU and TUNEL-reactive territories
Authors: De Marco N. , Campanella C. , Carotenuto R.
Published: July 2010

p27BBP/eIF6 (β4 binding protein/eukaryotic initiation factor 6) is a highly conserved protein necessary for cell life. In adult eIF6 mice, a 50% decrease in the protein levels in all tissues is accompanied by a reduction in cell proliferation only in the liver, fat cells and cultured fibroblasts. During X. laevis embryogenesis expression of p27BBP/eIF6 is abundant in high proliferative territories. However, in Xenopus cell proliferation appears unaffected following p27BBP/eIF6 over-expression or down-regulation. Indeed, p27BBP/eIF6 is an anti-apoptotic factor acting upstream of Bcl2 that reduces endogenous apoptosis. We studied p27BBP/eIF6 protein localization in wild type embryos and compared it to proliferation and apoptosis. At the beginning of embryogenesis, high levels of p27BBP/eIF6, proliferation and apoptosis overlap. In later development stages high proliferation levels are present in the same regions where higher p27BBP/eIF6 expression is observed, while apoptosis does not appear specifically concentrated in the same sites. The higher presence of p27BBP/eIF6 would appear related to an increased need of apoptosis control in the regions where cell death is essential for normal development.
Calorimetry as a tool for understanding biomolecular interactions and an aid to drug design
Authors: Ladbury John E.
Published: July 2010

The binding of two biomolecules viewed from the atomic level is highly complex. It involves the formation or removal of many individual non-covalent bonds both between the interacting molecules as well as with solvent. Currently, our understanding of the thermodynamic quantification of biomolecular interactions is somewhat naïve. ITC (isothermal titration calorimetry) provides a rapid route to a full thermodynamic characterization of a biomolecular interaction. Armed with these data, what are we really able to understand about complex formation and can any of this information provide a useful tool to aid drug development? Correlations between thermodynamic data and structural detail have been investigated, allowing insight into ways in which these can be used to understand protein–ligand interactions and provide input into the decision-making process in drug development.
Role of stem-cell-derived hepatic endoderm in human drug discovery
Authors: Medine Claire N. , Greenhough Sebastian , Hay David C.
Published: July 2010

Accurate prediction of human drug toxicity is a vital part of the drug discovery process. However, the safety evaluation process is hindered by the availability and quality of primary human liver models with which to study drug toxicity. In an attempt to overcome this limitation, research has focused on deriving human hepatocytes from a number of sources, including progenitors from fetal and adult liver, human cell lines derived from liver tumours, immortalized human hepatocytes and pluripotent stem cells. The major hurdles in developing scalable and high-fidelity human hepatocytes from hepatic cell lines and fetal and adult progenitors have been limited organ availability, homogeneous cell purification, short-term cell culture, and the rapid loss of hepatocyte phenotype and function in culture. Therefore it has been necessary to find alternative sources of human hepatocytes which circumvent these issues. The research in our group has focused on generating human hepatic endoderm from the scalable pluripotent stem cell populations, human embryonic stem cells and induced pluripotent stem cells. We have developed efficient and scalable models of human hepatocyte differentiation from these cell populations. Moreover, stem-cell-derived hepatic endoderm displays many of the functional attributes of primary human hepatocytes. Our research is now focused on developing defined culture systems and improving cell culture microenvironments in order to improve our understanding of the mechanisms regulating human liver development. This will in turn facilitate the generation of broad-range functioning hepatic endoderm in vitro. By taking these approaches, we believe that it will be possible to improve the predictive nature of our in vitro models, revolutionizing the manner in which industry measures human drug toxicity and having an impact on drug attrition.
The potential of small chemical functional groups for directing the differentiation of kidney stem cells
Authors: Murray Patricia , Vasilev Krasimir , Fuente Mora Cristina , Ranghini Egon , Tensaout Hayeit , Rak-Raszewska Aleksandra , Wilm Bettina , Edgar David , Short Robert D. , Kenny Simon E.
Published: July 2010

In the future, stem-cell-based therapies could offer new approaches to treat kidney disease and reduce the incidence of ESRD (end-stage renal disease), but, as yet, research in this area is only being conducted in rodents and it is not clear whether or when it could be applied to human patients. Drug therapies, on the other hand, have been very effective at delaying the progression of kidney disease, but, for various reasons, current drug regimes are not suitable for all patients. A greater understanding of the molecular mechanisms that underlie disease progression in chronic kidney disease could help to identify novel drug targets. However, progress in this area is currently hindered due to the lack of appropriate in vitro culture systems for important renal cell types, such as proximal tubule cells and podocytes. This problem could be overcome if it were possible to direct the differentiation of kidney stem cells to renal cell types in vitro. In the present review, we highlight the potential of surface gradients of small chemical functional groups to direct the differentiation of kidney stem cells.
Determinants of ELAV gene-specific regulation
Authors: Soller Matthias , Li Min , Haussmann Irmgard U.
Published: July 2010

How RNA-binding proteins recognize their complement of targets in a complex cellular environment remains poorly understood. Sequence degeneracy and redundancy of short motifs at genomic scales have mostly eluded predictions of specific target genes for gene-specific ELAV (embryonic lethal abnormal visual system)/Hu proteins that bind ubiquitous AU-rich motifs. Using the genetic tools of Drosophila, we have analysed binding properties of ELAV in vitro and ELAV-dependent regulation of its major target ewg (erect wing) in neurons. These studies reveal that an integral part of ELAV gene-specific regulation involves combinatorial binding to variably spaced short U-rich motifs on an extensive binding site.
Lateralized human hippocampal activity predicts navigation based on sequence or place memory
Authors: Iglói Kinga , Doeller Christian F. , Berthoz Alain , Rondi-Reig Laure , Burgess Neil
Published: July 2010

The hippocampus is crucial for both spatial navigation and episodic memory, suggesting that it provides a common function to both. Here we adapt a spatial paradigm, developed for rodents, for use with functional MRI in humans to show that activation of the right hippocampus predicts the use of an allocentric spatial representation, and activation of the left hippocampus predicts the use of a sequential egocentric representation. Both representations can be identified in hippocampal activity before their effect on behavior at subsequent choice-points. Our results suggest that, rather than providing a single common function, the two hippocampi provide complementary representations for navigation, concerning places on the right and temporal sequences on the left, both of which likely contribute to different aspects of episodic memory.
D-peptide inhibitors of the p53–MDM2 interaction for targeted molecular therapy of malignant neoplasms
Authors: Liu Min , Li Chong , Pazgier Marzena , Li Changqing , Mao Yubin , Lv Yifan , Gu Bing , Wei Gang , Yuan Weirong , Zhan Changyou , Lu Wei-Yue , Lu Wuyuan
Published: July 2010

The oncoproteins MDM2 and MDMX negatively regulate the activity and stability of the tumor suppressor protein p53, conferring tumor development and survival. Antagonists targeting the p53-binding domains of MDM2 and MDMX kill tumor cells both in vitro and in vivo by reactivating the p53 pathway, promising a class of antitumor agents for cancer therapy. Aided by native chemical ligation and mirror image phage display, we recently identified a D-peptide inhibitor of the p53-MDM2 interaction termed
D
PMI-α (TNWYANLEKLLR) that competes with p53 for MDM2 binding at an affinity of 219 nM. Increased selection stringency resulted in a distinct D-peptide inhibitor termed
D
PMI-γ (DWWPLAFEALLR) that binds MDM2 at an affinity of 53 nM. Structural studies coupled with mutational analysis verified the mode of action of these D-peptides as MDM2-dependent p53 activators. Despite being resistant to proteolysis, both
D
PMI-α and
D
PMI-γ failed to actively traverse the cell membrane and, when conjugated to a cationic cell-penetrating peptide, were indiscriminately cytotoxic independently of p53 status. When encapsulated in liposomes decorated with an integrin-targeting cyclic-RGD peptide, however,
D
PMI-α exerted potent p53-dependent growth inhibitory activity against human glioblastoma in cell cultures and nude mouse xenograft models. Our findings validate D-peptide antagonists of MDM2 as a class of p53 activators for targeted molecular therapy of malignant neoplasms harboring WT p53 and elevated levels of MDM2.
Syringyl lignin biosynthesis is directly regulated by a secondary cell wall master switch
Authors: Zhao Qiao , Wang Huanzhong , Yin Yanbin , Xu Ying , Chen Fang , Dixon Richard A.
Published: July 2010

Lignin is a major component of plant secondary cell walls and is derived from
p
-hydroxyphenyl (H), guaiacyl (G), and syringyl (S) monolignols. Among higher plants, S lignin is generally considered to be restricted to angiosperms, which contain the S lignin-specific cytochrome P450-dependent monooxygenase, ferulic acid/coniferaldehyde/coniferyl alcohol 5-hydoxylase (F5H). The transcription factor MYB58 directly regulates expression of monolignol pathway genes except for
F5H
. Here we show that
F5H
expression is directly regulated by the secondary cell wall master switch NST1/SND1, which is known to regulate expression of MYB58. Deletion of
NST1
expression in
Medicago truncatula
leads to a loss of S lignin associated with a more than 25-fold reduction of
F5H
expression but only around a 2-fold reduction in expression of other lignin pathway genes. A detailed phylogenetic analysis showed that gymnosperms lack both
F5H
and orthologs of
NST1/SND1
. We propose that both
F5H
and
NST1
appeared at a similar time after the divergence of angiosperms and gymnosperms, with F5H possibly originating as a component of a defense mechanism that was recruited to cell wall biosynthesis through the evolution of NST1-binding elements in its promoter.
Internal representation and memory formation of odor preference based on oscillatory activities in a terrestrial slug
Authors: Sekiguchi Tatsuhiko , Furudate Hiroyuki , Kimura Tetsuya
Published: July 2010

The terrestrial slug Limax exhibits a highly developed ability to learn odors with a small nervous system. When a fluorescent dye, Lucifer Yellow (LY), is injected into the slug's body cavity after odor–taste associative conditioning, a group of neurons in the procerebral (PC) lobe, an olfactory center of the slug, is labeled by LY. We examined the relationships between conditioning strategies and LY labeling. The positions of LY-labeled neurons in the PC lobe after appetitive conditioning were more apical than those after aversive conditioning and did not depend on the conditioned odor, suggesting that the biological value of odors affected the position of LY-labeled neural clusters. A simple computational model consisting of two layers of oscillators with electrical synaptic interaction was constructed based on physiological features of the PC lobe, and showed that the oscillatory phase difference between the layers contributed to determination of the positions of LY-labeled neurons, suggesting that phase difference in oscillatory activity plays a role in the association of odors and the preference for them.
The Ternary Systems Leucite—Corundum—Spinel and Leucite—Forsterite—Spinel
Authors: SCHAIRER J. F.
Published: July 2010

These ternary systems are limiting faces, respectively, of the volumes leucite‐corundum‐spinel‐silica and leucite‐forsterite‐spinel‐silica in the quaternary system K2O–MgO–Al2O3–SiO2. The results of quenching experiments on these two ternary systems and on the binary system spinel‐leucite are given here. The relation of the system leucite‐corundum‐spinel to the volume leucite‐corundum‐spinel‐K2O·Al2O3·2SiO2 is indicated. The data presented are of general interest to the geologist and provide basic information which can be applied to refractories and slags by the ceramist and metallurgist. Some observations are made on the refractoriness and changes in refractoriness of certain mixtures of ceramic materials.
Preparation of Ultrafine Zirconia Particles
Authors: Xie Yuqun
Published: July 2010

Ultrafine ZrO2 particles have been prepared via a new sol‐gel process. This process involves the addition of excess C2H4O into the aqueous ZrOCl2 solution and reacting the mixture at room temperature; a glassy ZrO(OH)2 gel is formed moments later. An ultrafine ZrO2 powder is obtained after the gel is dried and calcined; the powder is monoclinic. The average particle size is ∼12 nm, and its specific surface area is 55.1 m2/g. In addition, partially stabilized ZrO2 can be prepared in the same manner, yielding a good result.
Dispersant‐Binder Interactions in Aqueous Silicon Nitride Suspensions
Authors: Paik Ungyu , Hackley Vincent A. , Lee Hae‐Weon
Published: July 2010

The interaction of dispersant and binder on the surface of particles was studied to identify the effect of these additives on aqueous ceramic powder processing. Poly(methacrylic acid) (PMAA) and poly(vinyl alcohol) (PVA) were used as the dispersant and binder, respectively. The adsorption isotherms of the organic additives on silicon nitride were determined. The adsorption of PMAA was differentiated from PVA in the mixed additive system via ultraviolet spectroscopy. The electrokinetic behavior of silicon nitride was measured by using an electrokinetic sonic amplitude analyzer. As the PMAA concentration increased, the isoelectric point (pHiep) of silicon nitride shifted from pH 6.7 ± 0.1 to acidic pH values. The magnitude of the shift depended on the surface coverage of PMAA. PVA did not affect the pHiep of suspensions but did cause a moderate decrease in the near‐surface potential. Finally, the rheological behavior of silicon nitride suspensions was measured to assess the stability of particles against flocculation in aqueous media; this behavior was subsequently correlated with the electrokinetic and adsorption isotherm data.
Rheological Behavior of Slurries and Consolidated Bodies Containing Mixed Silicon Nitride Networks
Authors: Fisher Matthew L. , Lange Fred F.
Published: July 2010

Two particle networks, each formulated with a different interparticle potential, were mixed to control the rheological properties of ceramic slurries and to develop claylike plasticity in consolidated bodies. A weakly attractive network, containing silicon nitride powder, alkylated with hexadecanol, was mixed with a second slurry containing flocculated (nonalkylated) silicon nitride powder. The elastic modulus and apparent yield stress of concentrated suspensions containing each constituent and their mixtures were found to increase with volume fraction according to a previously reported power law function (exponents of 4.8 and 3.75, respectively). Because of the large difference in the relative strengths of the two networks, the flocculated network overwhelmingly controlled the behavior of the mixed slurries when its volume fraction (relative to total solids) exceeded 0.30. Slurries were consolidated by pressure filtration, and the saturated bodies were tested in uniaxial compression. Bodies containing only alkylated powder packed to a high volume fraction and deformed at a low flow stress. The addition of small amounts of the flocculated network increased the flow stress to produce a body with rheological properties similar to clay.
Fabrication of Continuous‐SiC‐Fiber‐Reinforced SiAlON‐Based Ceramic Composites by Reactive Melt Infiltration
Authors: Kitaoka Satoshi , Kawashima Naoki , Suzuki Toshiyuki , Sugita Yuji , Shinohara Nobuo , Higuchi Takashi
Published: July 2010

A technique for fabrication of β′‐SiAlON‐based ceramics in three‐dimensional woven fabrics of BN‐coated SiC (Hi‐Nicalon™) fibers was developed by reactive melt infiltration in a controlled N2 atmosphere. β′‐SiAlON was produced in situ by the reaction of β‐Si3N4, AlN, and Y‐Al‐Si‐O molten glass. The wettability of the fibers with the molten glass was improved by infiltration and pyrolysis of perhydropolysilazane, resulting in fully dense matrix composites. The reaction between the fiber and molten glass could be depressed by increasing the N2 partial pressure during the melt infiltration. The inhibition of the interfacial reaction may be related to the formation of carbon and oxynitride on the SiC fiber, in agreement with thermodynamic calculations as a function of N2 partial pressure. The fabricated composites had a high ultimate flexure strength and a large work of fracture at room temperature. Degradation of the mechanical performance of the composites was small, even at 1773 K in an argon atmosphere.