bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Asymmetric Synthesis of Synthetic Alkaloids by a Tandem Biocatalysis/Ugi/Pictet—Spengler‐Type Cyclization Sequence.
Authors: Znabet Anass , Zonneveld Job , Janssen Elwin , De Kanter Frans J. J. , Helliwell Madelaine , Turner Nicholas J. , Ruijter Eelco , Orru Romano V. A. 
Published: February 2011

Abstract3,4‐cis‐substituted imines, such as (I), prepared via biocatalytic desymmetrization as reported earlier, are used as imine components in an Ugi‐type multicomponent reaction.
ChemInform Abstract: Synthesis and Antiinflammatory Activity of Derivatives of Coumarino‐Lignoid, Cleomiscosin A and Its Methyl Ether.
Authors: Sharma Shelly , Chattopadhyay S. K. , Trivendi Priyanka , Bawankule D. U. 
Published: February 2011

AbstractSix novel nitrated or halogenated derivatives of cleomiscosin A (I) are synthesized.
ChemInform Abstract: Red Fluorescent Organic Light‐Emitting Diodes Using Modified Pyran‐Containing DCJTB Derivatives.
Authors: Lee Kum Hee , Kim Sung Min , Kim Jeong Yeon , Kim Young Kwan , Yoon Seung Soo 
Published: February 2011

AbstractTwo new fluorescent compounds Red 1 (I) and Red 2 (II) are developed.
ChemInform Abstract: Amplification of the Inhibitory Activity and Reversal of the Selectivity of Miglitol by C(2′)‐Monofluorination.
Authors: Prell Erik , Korb Claudia , Kluge Ralph , Stroehl Dieter , Csuk Rene 
Published: February 2011

AbstractSelective monofluorination of the α‐glycosidase inhibitor and antidiabetic agent miglitol at positions C(2′) (Ia) or C(6) (Ib) creates competitive inhibitors of glycosidases.
ChemInform Abstract: ε‐Fe2O3: An Advanced Nanomaterial Exhibiting Giant Coercive Field, Millimeter‐Wave Ferromagnetic Resonance, and Magnetoelectric Coupling
Authors: Tucek Jiri , Zboril Radek , Namai Asuka , Ohkoshi Shin‐ichi 
Published: February 2011

AbstractReview: 104 refs.
ChemInform Abstract: Cyclopalladated Ferrocenylimines as Efficient Catalysts for Homogeneous Catalysis. A Brief Introduction to Our Preliminary Achievements
Authors: Wu Yang Jie , Yang Fan , Zhang Jin Li , Cui Xiu Ling , Gong Jun Fang , Song Mao Ping , Li Tie Sheng 
Published: February 2011

AbstractReview: 56 refs.
ChemInform Abstract: Progress Toward the First Observation of Parity Violation in Chiral Molecules by High‐Resolution Laser Spectroscopy
Authors: Darquie Benoit , Stoeffler Clara , Shelkovnikov Alexander , Daussy Christophe , Amy‐Klein Anne , Chardonnet Christian , Zrig Samia , Guy Laure , Crassous Jeanne , Soulard Pascale , et al. et al. 
Published: February 2011

AbstractReview: 104 refs.
Shape‐Persistent Macrocycles as Ligands and Sensitisers of Nd3+ Ions
Authors: Gallina Maria Elena , Giansante Carlo , Ceroni Paola , Venturi Margherita , Sakamoto Junji , Schlüter A. Dieter 
Published: February 2011

AbstractTwo shape‐persistent macrocycles with a hexagonal backbone incorporating two bpy units and two nonchromophoric methoxytetrahydropyran units (M), or two coumarin 2 dyes (C2–M–C2) are highly absorbing and emitting species in dichloromethane solution (ϵmax = 1.90 × 105 M–1 cm–1 at 308 nm and 1.92 × 105 M–1 cm–1 at 309 nm; φem = 0.60 and 0.73, τ = 0.76 and 3.6 ns for M and C2–M–C2, respectively). Time‐resolved fluorescence anisotropy measurements of M in dichloromethane has given information on the hydrodynamic volume of the free macrocycle in solution, which is close to the molecular volume measured by X‐ray crystallographic analysis. M and C2–M–C2 are very good ligands for lanthanide ions (Nd3+ and Gd3+): they form complexes with 1:2, 1:1 and 2:1 (clearly evident only in the case of M) metal to ligand stoichiometry. These complexes are characterised by very high association constants in dichloromethane solution, as demonstrated by significant changes to the photophysical properties of the macrocycles. In the 1:2 and 1:1 complexes, the lanthanide ion is likely sandwiched between two macrocycles and coordinated by two bpy units. The efficiency of energy transfer from the ligand to the lanthanide ion is quite high (73 % in the case of the [Nd2M]6+ complex), and it is not sensitive to the presence of oxygen. For the Nd3+ complexes with the C2–M–C2 macrocycle, sensitisation of the lanthanide NIR emission takes place with lower efficiency (ca. 50 %), due to a competitive electron transfer process from the coumarin to the complexed macrocycle. Lastly, upon addition of an excess of a competitive ligand, all the absorption and emission spectroscopic changes are completely reversible.
Improved One‐Pot Synthesis of C3‐Symmetric ClickPhos and Related Ligands: Structures of Unique Triazole–Zinc Complexes
Authors: Zink Daniel M. , Baumann Thomas , Nieger Martin , Bräse Stefan 
Published: February 2011

AbstractA number of ClickPhos‐type ligands have been prepared by using an improved one‐pot procedure. Several [tris(triazolyl)phosphane]zinc complexes have been synthesized and characterized by X‐ray structure analyses.
A Cross‐Metathesis–Conjugate Addition Route to Enantiopure γ‐Butyrolactams and γ‐Lactones from a C2‐Symmetric Precursor
Authors: Schmidt Bernd , Staude Lucia , Kelling Alexandra , Schilde Uwe 
Published: February 2011

AbstractA protected derivative of (3R,4R)‐hexa‐1,5‐diene‐3,4‐diol, a conveniently accessible C2‐symmetric building block, undergoes single or double cross metathesis with methyl acrylate. The cross metathesis products are amenable to stereoselective conjugate addition reactions and can be converted into either γ‐butyrolactones or γ‐lactams.
Dynamic Kinetic Resolution of a Wide Range of Secondary Alcohols: Cooperation of Dicarbonylchlorido(pentabenzylcyclopentadienyl)ruthenium and CAL‐B
Authors: Päiviö Mari , Mavrynsky Denys , Leino Reko , Kanerva Liisa T. 
Published: February 2011

AbstractThe substrate scope in the dynamic kinetic resolution ofsecondary alcohols was studied by using 31 structurallydifferent alcohols and isopropenyl acetate in the presence ofdicarbonylchlorido(pentabenzylcyclopentadienyl)rutheniumand Candida antarctica lipase B (Novozym 435, CAL‐B) in toluene. The enzyme and the ruthenium complex were shown to function in a highly compatible manner allowing the conversion of the racemic alcohols into the (R)‐acetates in practically theoretical yields and, in most cases, ee values exceeding 99 %. The results are fully comparable to those published previously by using earlier reported, state‐of‐the‐art ruthenium‐based catalysts for the alcohol racemization. A clear benefit of the dicarbonylchlorido(pentabenzylcyclopentadienyl)ruthenium system, when compared to other (cyclopentadienyl)ruthenium racemization catalysts, is its simple and cost‐efficient preparation.
Continuous‐time random walk models of DNA electrophoresis in a post array: Part II. Mobility and sources of band broadening
Authors: Olson Daniel W. , Dutta Sarit , Laachi Nabil , Tian Mingwei , Dorfman Kevin D. 
Published: February 2011

AbstractUsing the two‐state, continuous‐time random walk model, we develop expressions for the mobility and the plate height during DNA electrophoresis in an ordered post array that delineate the contributions due to (i) the random distance between collisions and (ii) the random duration of a collision. These contributions are expressed in terms of the means and variances of the underlying stochastic processes, which we evaluate from a large ensemble of Brownian dynamics simulations performed using different electric fields and molecular weights in a hexagonal array of 1 μm posts with a 3 μm center‐to‐center distance. If we fix the molecular weight, we find that the collision frequency governs the mobility. On the contrary, the average collision duration is the most important factor for predicting the mobility as a function of DNA size at constant Péclet number. The plate height is reasonably well described by a single post rope‐over‐pulley model, provided that the extension of the molecule is small. Our results only account for dispersion inside the post array and thus represent a theoretical lower bound on the plate height in an actual device.
Energy consumption balancing (ECB) issues and mechanisms in wireless sensor networks (WSNs): a comprehensive overview
Authors: Ishmanov Farruh , Malik Aamir Saeed , Kim Sung Won 
Published: February 2011

ABSTRACTWireless sensor networks comprise of a large number of low cost sensor nodes that have strictly restricted sensing, computation and communication capabilities. In addition to this, sensor nodes have limited battery life which is not rechargeable in many applications. Due to resource limitations for the sensor nodes, it is important to use energy efficiently for each sensor node. This will result in prolonged network lifetime and functionality. Energy consumption balancing (ECB) property ensures that the average energy dissipation per sensor is equal for all sensors in the network. ECB can be considered as energy efficiency property that optimally manages energy consumption of sensors to prolong network lifetime. This paper investigates the ECB theory and ECB related mechanisms. A classification of ECB mechanism is given by surveying the current and state of the art research in this area. In addition, comparison and main constraints of the mechanisms are presented. Copyright © 2011 John Wiley & Sons, Ltd.
Carrier sense adaptation with enhanced fairness in IEEE 802.15.4 WPAN
Authors: Park Kyung‐Joon , Jeong Kwanhee , Lim Hyuk , Park Daeyoung 
Published: February 2011

AbstractWe propose an adaptive carrier sense (CS) scheme with enhanced fairness based on an observation that the conventional adaptive CS mechanism may lead to significant unfairness. Our experimental study with an IEEE 802.15.4 WPAN testbed shows that the proposed algorithm significantly improves fairness compared to the conventional mechanism while providing competitive throughput performance. Copyright © 2011 John Wiley & Sons, Ltd.
Coast erosion at Aberystwyth; the geological and human factors involved
Authors: Wood A. 
Published: February 2011

AbstractThe northern portion of the promenade at Aberystwyth is at present dangerously vulnerable to wave attack. The main factor involved is the geological evolution of the coastline which now strictly limits the available protective shingle and sand cover. The action of man, in building harbour protection works, protective sea walls and groynes, has had unforeseen consequences.
Caprionichnus, a new trace fossil from the Caradocian of southern Norway
Authors: Harland T. L. 
Published: February 2011

AbstractCaprionichnus steinvikensis ichnogen. et sp. nov. is described from a mixed carbonate‐terrigenous mudstone sequence of offshore marine origin, which forms the upper part of the Encrinite Limestone (Caradocian) in the Langesund area of southern Norway. The trace fossil is characterised by a chevron‐like arrangement of burrow pairs, some with a common central burrow. Systems consist of two to eight burrow pairs, burrow diameter varies between 5·5 and 11 mm and the angle between the paired burrows ranges between 41° and 67°. The burrows are interpreted as resulting from the probing activities of a deposit feeding organism with similar behaviour to that deduced for the producer of Chondrites by Simpson (1957), and it is suggested that the producer of Caprionichnus was capable of living both within and above its feeding level.
An unusual preservation of fossil plants from cumbria: Diagenetic and environmental significance
Authors: Nudds J. R. , Taylor P. D. 
Published: February 2011

AbstractLower Carboniferous fossil plants preserved as uncompressed external casts of calcite are recorded and described from a micritic limestone found in Cumbria. Most can be identified as the small leafy twigs of Archaeosigillaria kidstoni Kräusel and Weyland, but others are unidentified plant axes. Sporangia are recognised for the first time in Archaeosigillaria. Reasons for the unusual mode of preservation are considered. Rapid lithification of sediment is indicated by an erosional surface at the top of the plant bed and the presence of clasts of the latter in the overlying limestone. Subsequent plant decay probably left voids which became filled by acicular carbonate cement later altered to radiaxial fibrous calcite. The occurrence of inferred evaporite pseudomorphs in associated nodules suggests a highly saline environment which may have contributed to the lack of plant decomposition before burial.
A distinct subset of glioma cell lines with stem cell‐like properties reflects the transcriptional phenotype of glioblastomas and overexpresses CXCR4 as therapeutic target
Authors: Schulte Alexander , Günther Hauke S. , Phillips Heidi S. , Kemming Dirk , Martens Tobias , Kharbanda Samir , Soriano Robert H. , Modrusan Zora , Zapf Svenja , Westphal Manfred , Lamszus Katrin 
Published: February 2011

AbstractGlioblastomas contain stem‐like cells that can be maintained in vitro using specific serum‐free conditions. We investigated whether glioblastoma stem‐like (GS) cell lines preserve the expression phenotype of human glioblastomas more closely than conventional glioma cell lines. Expression profiling revealed that a distinct subset of GS lines, which displayed a full stem‐like phenotype (GSf), mirrored the expression signature of glioblastomas more closely than either other GS lines or cell lines grown in serum. GSf lines are highly tumorigenic and invasive in vivo, express CD133, grow spherically in vitro, are multipotent and display a Proneural gene expression signature, thus recapitulating key functional and transcriptional aspects of human glioblastomas. In contrast, GS lines with a restricted stem‐like phenotype exhibited expression signatures more similar to conventional cell lines than to original patient tumors, suggesting that the transcriptional resemblance between GS lines and tumors is associated with different degrees of “stemness”. Among markers overexpressed in patient tumors and GSf lines, we identified CXCR4 as a potential therapeutic target. GSf lines contained a minor population of CXCR4hi cells, a subfraction of which coexpressed CD133 and was expandable by hypoxia, whereas conventional cell lines contained only CXCR4lo cells. Convection‐enhanced local treatment with AMD3100, a specific CXCR4 antagonist, inhibited the highly invasive growth of GS xenografts in vivo and cell migration in vitro. We thus demonstrate the utility of GSf lines in testing therapeutic agents and validate CXCR4 as a target to block the growth of invasive tumor‐initiating glioma stem cells in vivo. © 2011 Wiley‐Liss, Inc.
Inducible gene expression in GFAP+ progenitor cells of the SGZ and the dorsal wall of the SVZ—A novel tool to manipulate and trace adult neurogenesis
Authors: Weber Tillmann , Baier Vera , Pauly Rahel , Sahay Amar , Baur Max , Herrmann Elke , Ciccolini Francesca , Hen René , Kronenberg Golo , Bartsch Dusan 
Published: February 2011

AbstractIn the adult mammalian brain, neurogenesis originates from astrocyte‐like stem cells. We generated a transgenic mouse line in which the tetracycline dependent transactivator (tTA) is expressed under the control of the murine GFAP promoter. In this mouse line, inducible gene expression targets virtually all GFAP‐expressing stem‐like cells in the dentate gyrus and a subset of GFAP‐expressing progenitors located primarily in the dorsal wall/dorsolateral corner of the subventricular zone. Outside the neurogenic zones, astrocytes are infrequently targeted. We introduce a panel of transgenic mice which allow both inducible expression of candidate genes under control of the murine GFAP promoter and, at the same time, lineage tracing of all cells descendant from the original GFAP‐positive cell. This new mouse line represents a versatile tool for functional analysis of neurogenesis and lineage tracing. © 2011 Wiley‐Liss, Inc.
Isocitrate dehydrogenase mutations: A challenge to traditional views on the genesis and malignant progression of gliomas
Authors: Weller Michael , Wick Wolfgang , von Deimling Andreas 
Published: February 2011

AbstractIsocitrate dehydrogenases (IDHs) convert isocitrate to α‐ketoglutarate by oxidative decarboxylation and are thereby involved in multiple metabolic processes. Mutations in the genes encoding IDH1 and IDH2 were first reported in human gliomas in 2008 and later on also identified in a minority of patients with acute myeloid leukemia. The mutations universally affect codons 132 in IDH1 and 172 in IDH2 and result in decreased enzymatic activity. The oncogenic pathway triggered by IDH mutations may involve the activation of hypoxia‐inducible factor pathway as well as the acquisition of a novel (gain of enzymatic) function consuming NADPH and generating α‐hydroxyglutarate. Most intriguingly, IDH mutations are observed in ∼70–80% of grade II/III gliomas and the majority of secondary glioblastomas, but only 10% of primary glioblastomas, suggesting a different cellular origin of the gliomas, which had previously been viewed as a multistep process of malignant progression. Understanding the oncogenic pathway mediated by mutant IDH might result in the development of novel, tailored pharmacological therapies for human glioma patients. © 2011 Wiley‐Liss, Inc.
An Alzheimer's disease‐relevant presenilin‐1 mutation augments amyloid‐beta‐induced oligodendrocyte dysfunction
Authors: Desai Maya K. , Guercio Brendan J. , Narrow Wade C. , Bowers William J. 
Published: February 2011

AbstractWhite matter pathology has been documented in the brains of familial Alzheimer's disease (FAD)‐afflicted individuals during presymptomatic and preclinical stages of AD. How these defects in myelination integrity arise and what roles they may play in AD pathophysiology have yet to be fully elucidated. We previously demonstrated that triple‐transgenic AD (3xTg‐AD) mice, which harbor the human amyloid precursor Swedish mutation, presenilin‐1 M146V (PS1M146V) knock‐in mutation, and tauP301Lmutation, exhibit myelin abnormalities analogous to FAD patients and that Aβ1‐42contributes to these white matter deficits. Herein, we demonstrate that the PS1M146Vmutation predisposes mouse oligodendrocyte precursor (mOP) cells to Aβ1‐42‐induced alterations in cell differentiationin vitro. Furthermore, PS1M146Vexpression compromised mOP cell function and MBP protein distribution, a process that is further aggravated with exposure to Aβ1‐42. We found that the myelination defect and MBP subcellular mislocalization triggered by PS1M146Vand Aβ1‐42can be effectively prevented by treatment with the GSK‐3β inhibitor, TWS119, thereby implicating GSK‐3β kinase activity in this pathogenic cascade. Overall, this work provides further mechanistic insights into PS1M146Vand Aβ1‐42‐driven oligodendrocyte dysfunction andmyelin damage during early presymptomatic stages of AD, and provides a new target in oligodendrocytes for developing therapies designed to avert AD‐related white matter pathology. © 2011 Wiley‐Liss, Inc.
FOXO3a inhibits TNF‐α‐ and IL‐1β‐induced astrocyte proliferation:Implication for reactive astrogliosis
Authors: Cui Min , Huang Yunlong , Tian Changhai , Zhao Yong , Zheng Jialin 
Published: February 2011

AbstractReactive astrogliosis is one of the pathological hallmarks of neurodegenerative diseases. Inflammatory cytokines, such as TNF‐α and IL‐1β, have been shown to mediate the reactive astrogliosis in neurodegenerative diseases; however, the molecular mechanism remains unclear. In this study, we investigated the role of transcription factor FOXO3a on astrocyte proliferation, one primary aspect of severe reactive astrogliosis. Our results confirmed that TNF‐α and IL‐1β increased astrocyte proliferation, as determined by Ki67 and BrdU immunostaining. Furthermore, we found that cytokine‐mediated astrocyte proliferation was accompanied by an increase of the phosphorylation and reduced nuclear expression of FOXO3a. Intracranial injection of TNF‐α and IL‐1β induced astrocyte proliferation and hypertrophy, which was associated with reduced nuclear expression of Foxo3a in astrocytes. To determine the function of FOXO3a in astrocyte proliferation, wild type FOXO3a was overexpressed with adenovirus, which subsequently upregulated p27Kip1 and Gadd45α, and significantly inhibited cytokine‐induced astrocyte proliferation. In contrast, overexpression of dominant negative FOXO3a decreased p27Kip1, upregulated cyclin D1 and promoted astrocyte proliferation. Along the same line, astrocytes isolated from Foxo3a‐null mice have higher proliferative potential. In response to intracranial injection of cytokines, Foxo3a‐null mice manifested severe astrogliosis in vivo. In conclusion, FOXO3a is important in restraining astrocyte proliferation during proinflammatory cytokine stimulation and loss of function of FOXO3a may be responsible for the proliferation of astrocytes in the severe form of reactive astrogliosis. Understanding the key regulatory role of FOXO3a in reactive astrogliosis may provide a novel therapeutic target during neuroinflammation. © 2011 Wiley‐Liss, Inc.
Zusammensetzung der Neutrallipide und deren Fettsäuren aus Wal‐Hirnen. II. Hirne von Finnwalen (Balaenoptera physalus)
Authors: Lesch Peter , Bernhard Karl 
Published: February 2011

AbstractPure lipids from 5 regions of brains from 6 whales have been separated into various fractions as cerebrosides, sphingomyelines, lecithines, ethanolamine cephalines, cholesterol and free fatty acids. The white matter contains mostly cholesterol and cerebrosides, the grey matter glycerophosphatides. The fatty acid composition of the cerebrosides from all regions is about the same. The fatty acids from sphingomyelines, lecithines, ethanolamine cephalines show significant differences in relation to their origin.
Etude de cyclohexanediols par spectrométrie de masse
Authors: Buchs A. 
Published: February 2011

AbstractLow resolution mass spectra of cyclohexane‐1,2‐diols and of deuterium labelled cyclohexane‐1,2‐diols cis and trans have been measured. The results indicate that it is easy to differentiate between positional isomers and that the stereochemistry of cyclohexane‐1,2‐diols can be deduced from the mass spectra. In the 1,2‐diols the elimination of water under electron impact occurs simultaneously in three ways: (a) between an OH group and a H atom in position 1,4, (b) between the two OH groups, (c) without participation of the II atoms of the OH groups. Difficulties encountered in deducing unambiguous fragmentation patterns are discussed.
ESR.‐Messungen an Radikal‐Anionen Trimethylsilyl‐substituierter π‐Elektronensysteme
Authors: Gerson F. , Heinzer J. , Bock H. , Alt H. , Seidl H. 
Published: February 2011

AbstractThe ESR spectra of the radical anions of several trimethylsilyl substituted polyenes, benzenes and naphthalenes have been recorded; most of them are surprisingly stable under the conditions of measurement. Accurate values could be obtained for the splitting parameters – not only of the protons, but also of the 29Si isotopes in natural abundance. The coupling constants of the 29Si nuclei in trimethylsilyl substituents are of the same order of magnitude as the corresponding values of the protons attached to centers of comparable π‐spin population. The results indicate some Si ← Cπ delocalization.