bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Preparation of Silica Aerogels/Polystyrene Microspheres with Core-Shell Structure
Authors: Geng Gang Qiang , Liu Xin Jun , Bian Gong Xun
Published: July 2010

With silane coupling agent on silica aerogels by modification pretreatment, we obtained the core-shell structure of polystyrene grafted mesoporous silica aerogels through the dispersion polymerization process. By Orthogonal design method to study the effects of the system, results showed that: the greatest influence of the system component on the conversion rates was the mass ratio of silica aerogels and styrene and the best parameter value was obtained. By analyzing the effects of the initiator and dispersion technology, we obtained a core-shell structure whose stable coating was 70% with organic initiator AIBN as initiator after a unique ultrasound technique. Through TEM the core-shell structure was characterized.
Direct Presentation Regulates the Magnitude of the CD8+ T Cell Response to Cell-Associated Antigen through Prolonged T Cell Proliferation
Authors: Tatum Angela M. , Watson Alan M. , Schell Todd D.
Published: July 2010

The magnitude and complexity of Ag-specific CD8+ T cell responses is determined by intrinsic properties of the immune system and extrinsic factors, such as vaccination. We evaluated mechanisms that regulate the CD8+ T cell response to two distinct determinants derived from the same protein Ag, SV40 T Ag (T Ag), following immunization of C57BL/6 mice with T Ag-transformed cells. The results show that direct presentation of T cell determinants by T Ag-transformed cells regulates the magnitude of the CD8+ T cell response in vivo but not the immunodominance hierarchy. The immunodominance hierarchy was reversed in a dose-dependent manner by addition of excess naive T cells targeting the subdominant determinant. However, T cell competition played only a minor role in limiting T cell accumulation under physiological conditions. We found that the magnitude of the T cell response was regulated by the ability of T Ag-transformed cells to directly present the T Ag determinants. The hierarchy of the CD8+ T cell response was maintained when Ag presentation in vivo was restricted to cross-presentation, but the presence of T Ag-transformed cells capable of direct presentation dramatically enhanced T cell accumulation at the peak of the response. This enhancement was due to a prolonged period of T cell proliferation, resulting in a delay in T cell contraction. Our findings reveal that direct presentation by nonprofessional APCs can dramatically enhance accumulation of CD8+ T cells during the primary response, revealing a potential strategy to enhance vaccination approaches.
TLR9-Targeted Biodegradable Nanoparticles as Immunization Vectors Protect against West Nile Encephalitis
Authors: Demento Stacey L. , Bonafé Nathalie , Cui Weiguo , Kaech Susan M. , Caplan Michael J. , Fikrig Erol , Ledizet Michel , Fahmy Tarek M.
Published: July 2010

Vaccines that activate humoral and cell-mediated immune responses are urgently needed for many infectious agents, including the flaviviruses dengue and West Nile (WN) virus. Vaccine development would be greatly facilitated by a new approach, in which nanoscale modules (Ag, adjuvant, and carrier) are assembled into units that are optimized for stimulating immune responses to a specific pathogen. Toward that goal, we formulated biodegradable nanoparticles loaded with Ag and surface modified with the pathogen-associated molecular pattern CpG oligodeoxynucleotides. We chose to evaluate our construct using a recombinant envelope protein Ag from the WN virus and tested the efficiency of this system in eliciting humoral and cellular responses and providing protection against the live virus. Animals immunized with this system showed robust humoral responses polarized toward Th1 immune responses compared with predominately Th2-biased responses with the adjuvant aluminum hydroxide. Immunization with CpG oligodeoxynucleotide-modified nanoparticles resulted in a greater number of circulating effector T cells and greater activity of Ag-specific lymphocytes than unmodified nanoparticles or aluminum hydroxide. Ultimately, compared with alum, this system offered superior protection in a mouse model of WN virus encephalitis.
Boutet de Monvel’s calculus and groupoids I
Authors: Aastrup Johannes , Melo Severino T. , Monthubert Bertrand , Schrohe Elmar
Published: July 2010

Can Boutet de Monvel’s algebra on a compact manifold with boundary be obtained as the algebra

\Psi^0(G)

of pseudodifferential operators on some Lie groupoid

G

? If it could, the kernel

{\mathcal G}

of the principal symbol homomorphism would be isomorphic to the groupoid C*-algebra

C^*(G)

. While the answer to the above question remains open, we exhibit in this paper a groupoid

G

such that

C^*(G)

possesses an ideal

\mathcal{I}

isomorphic to

{\mathcal G}

. In fact, we prove first that

{\mathcal G}\simeq\Psi\otimes{\mathcal K}

with the C*-algebra

\Psi

generated by the zero order pseudodifferential operators on the boundary and the algebra

\mathcal K

of compact operators. As both

\Psi\otimes \mathcal K

and

\mathcal{I}

are extensions of

C(S^*Y)\otimes \mathcal{K}

by

\mathcal{K}

(

S^*Y

is the co-sphere bundle over the boundary) we infer from a theorem by Voiculescu that both are isomorphic.
Effects of Hand-Arm and Whole-Body Vibrations on Heart of Motorcycle Rider
Authors: Shivakumara B.S. , Sridhar V.
Published: July 2010

Motorcycle riders are subjected to hand arm and whole body vibrations. Both these vibrations affect the health of the rider. This paper attempts to analyze the effects of these vibrations on heart using finite element simulation and experiments. Firstly, the hand arm and whole body vibration forces are measured by conducting experiments on different motorcycles and for various road conditions. These measured forces are applied to the finite element model of a motorcycle rider to predict the distribution of Von mises stress around heart. Secondly, the average relative heart rate, the hand arm and whole body vibration accelerations are measured with by conducting experiments on different riders with typical body mass index and for various road conditions. The variations in the vibrations magnitude and the Von mises stress around heart correlate well. The Von mises stress and heart rate are more sensitive to the hand arm vibrations than the whole body vibrations. This effect on the heart may cause a cardiac problem in the long run.
Influence of Air Conditioning Characteristics on Vehicle Interior Noise
Authors: Hammad Nabil
Published: July 2010

Reduction of Heating, Ventilation and Air Conditioning (HVAC) systems and other components such as engine and exhaust system has resulted the study on the vehicle noise as an increasingly important aspect for the automotive industry in meeting the passenger comfort requirements. In this paper, the influence of vehicle air conditioning characteristics such as the fan speed, engine speed and air conditioning positions (i.e., ON or OFF) on the vehicle interior Sound Pressure Level (SPL) is presented. The generation of noise and its transmission mechanisms are studied. The major contributors to the HVAC system airborne noise are the aerodynamic, mechanical and hydraulic noises from the compressor and handling units. Since the HVAC's fan is driven directly by the vehicle battery that is separated from the HVAC, the noise generation due to the fan speeds or positions can be directly obtained by turning the compressor to OFF and the fan to ON positions. Meanwhile, the mechanical and hydraulic noises can be obtained by extracting the airborne noise by turning the compressor to OFF and the fan to ON positions from those obtained by turning both the compressor and fan to ON position. The experimental results indicate that the principal source of vehicle noise is related to the aerodynamic noise and the noise level has shown considerable increase when both the fan and compressor units are turned to ON positions. For a specific fan speed, an increase in the noise due to the mechanical and hydraulic sources is observed for an increase in the engine speed.
Optical signatures of the filamentous cyanobacterium Leptolyngbya boryana during mass viral lysis
Authors: Simis Stefan G. H. , Tijdens Marjolijn , Hoogveld Hans L. , Gons Herman J.
Published: July 2010

The inherent optical properties of absorption and scattering, the population density of virus‐like particles, and the particle size distribution (PSD) for particles <0.7 µm of the filamentous cyanobacterium Leptolyngbya boryana were monitored for 72 h at 9‐h intervals following infection with cyanophage LPP‐1. Lorenz‐Mie scattering theory and the anomalous diffraction approximation were used to derive the refractive index representative of the bulk of particles and to model the particulate backscattering coefficient [bbp(λ)]. Upon lysis, particulate absorption [ap(λ)] and scattering [bbp(λ)] decreased, the number of free virus‐like particles increased drastically, the PSD shifted to relative abundance of small particles, and average trichome length decreased sharply. The complex refractive index of the bulk of particles was comparable with literature values for cyanobacteria. Modeled bbp(λ) spectra were lowered upon lysis, while backscattering probability increased. The effect of underrepresentation of particles below the measurement limit of the particle sizer was studied; more small particles in the PSD resulted in higher, but still relatively low, backscattering probability. The consequences of the studied optical behavior on spectral reflectance was explored. Significant spectral changes at longer wavelengths were mostly masked by water absorption at nominal population densities. However, strongly reduced ap(λ) in the red pigment absorption bands resulted in a pronounced green peak in reflectance spectra, and it was concluded that reflectance band ratio algorithms targeted at the absorption of the pigments phycocyanin and chlorophyll a can be used to detect the mass mortality caused by viral infection. The integrated intensity of reflected light was too variable to serve as an optical indicator for lytic events.
Evolutionary stoichiometry: The role of food quality for clonal differentiation and hybrid maintenance in a Daphnia species complex
Authors: Seidendorf Bernd , Boersma Maarten , Schwenk Klaus
Published: July 2010

Interspecific hybridization is a common phenomenon among Daphnia species (Crustacea: Anomopoda); interspecific hybrids and parental species have been shown to be ecologically differentiated and often co‐occur in the same lake. Food quantity, temperature, and the level of predation (by juvenile fish) have been identified as the main environmental factors determining the fitness of Daphnia taxa. Here we tested another environmental factor, food quality, which is known to shape fitness in Daphnia. We conducted life‐history experiments with clones of Daphnia galeata, Daphnia cucullata, and their interspecific hybrids and measured fitness‐related life‐history traits at two food quality conditions (phosphorus [P]‐rich and P‐limited algae). D. galeata × cucullata hybrids show highest fitness values in some traits at low food quality conditions, relative to the parental species, whereas D. galeata was superior in P‐rich conditions. These results, based on single‐clone life‐history studies, were confirmed by a multiclone experiment. Large natural variation in food quality and the observed differential response of clones and taxa to P variation indicates that variation in food quality represents an additional factor, besides fish predation and food quantity, explaining hybrid maintenance.
Water droplet calibration of a cloud droplet probe and in-flight performance in liquid, ice and mixed-phase clouds during ARCPAC
Authors: Lance S. , Brock C. A. , Rogers D. , Gordon J. A.
Published: July 2010

Abstract. Laboratory calibrations of the Cloud Droplet Probe (CDP) sample area and droplet sizing are performed using water droplets of known size, generated at a known rate. However, comparison with an independent measure of liquid water content (LWC) during in-flight operation suggests much greater biases in the droplet size and/or droplet concentration measured by the CDP than would be expected based on the laboratory calibrations. Since the bias in CDP-LWC is strongly concentration dependent, we hypothesize that this discrepancy is a result of coincidence, when two or more droplets pass through the CDP laser beam within a very short time. The coincidence error, most frequently resulting from the passage of one droplet outside and one inside the instrument sample area at the same time, is evaluated in terms of an "extended sample area" (SAE), the area in which individual droplets can affect the sizing detector without necessarily registering on the qualifier. The SAE is calibrated with standardized water droplets, and used in a Monte-Carlo simulation to estimate the effect of coincidence on the measured droplet size distributions. The simulations show that extended coincidence errors are important for the CDP at droplet concentrations even as low as 200 cm−3, and these errors are necessary to explain the trend between calculated and measured LWC observed in liquid and mixed-phase clouds during the Aerosol, Radiation and Cloud Processes Affecting Arctic Climate (ARCPAC) study. We estimate from the simulations that 60% oversizing error and 50% undercounting error can occur at droplet concentrations exceeding 500 cm−3. Modification of the optical design of the CDP is currently being explored in an effort to reduce this coincidence bias.
The model of own seismoelectromagnetic oscillations of LAI system
Authors: Kachakhidze M. K. , Kereselidze Z. A. , Kachakhidze N. K.
Published: July 2010

Abstract. Very low frequency (VLF) electromagnetic radiation (in diapason 1 kHz – 1 MHz) in atmosphere, generated during earthquake preparation period, may be connected with linear size, characterizing incoming earthquake source. In order to argue this hypothesis very simple quasi-electrostatic model is used: local VLF radiation may be the manifestation of own electromagnetic oscillations of concrete seismoactive segments of lithosphere-atmosphere system. This model explains qualitatively well-known precursor effects of earthquakes. At the same time, it will be principally possible to forecast expected earthquake with certain precision if we use this model after diagnosing existed data. As physical basis of working hypothesis is atmospheric effect of polarization charges occurred in surface layer of the Earth, it is possible to test the below constructed model in medium, where reasons of polarization charge generation may be different from piezoelectric mechanism, for example, due to electrolytic hydration.
Antireflective Nanoparticle Arrays Enhance the Efficiency of Silicon Solar Cells
Authors: Wan Dehui , Chen Hsuen‐Li , Tseng Te‐Chen , Fang Cheng‐Yi , Lai Yu‐Shen , Yeh Fang‐Yao
Published: July 2010

In this study, the phenomenon of light trapping in Si solar cells coated with metal (Au) and dielectric (TiO2, SiO2) nanoparticles (NPs) is systematically investigated. In contrast to previous reports, herein it is proposed that the photocurrent enhancement of solar cells should be attributed to the limited antireflection ability of the Au NP arrays. In other words, the Au NP arrays might not enhance the absorption of the active layer in cells when no light is reflected from the air–substrate interface. Therefore, the Au NPs are replaced with dielectric NPs, which possess lower extinction coefficients, and then the antireflection property of the TiO2 NP arrays is optimized. A simple, rapid, and cheap solution‐based method is used to prepare close‐packed TiO2 NP films on Si solar cells; these devices exhibit a uniform and remarkable increase (ca. 30%) in their photocurrents. To the best of the authors’ knowledge, this uniform photocurrent enhancement is greater than those obtained from previously reported metal and dielectric NP–enhanced Si wafer‐based solar cells.
Synthesis of poly(ε‐caprolactone)/clay nanocomposites using polyhedral oligomeric silsesquioxane surfactants as organic modifier and initiator
Authors: Hossain Md. D. , Yoo Youngjae , Lim Kwon T.
Published: July 2010

Poly(ε‐caprolactone)/clay nanocomposites were synthesized by in situ ring‐opening polymerization of ε‐caprolactone in the presence of montmorillonite modified by hydroxyl functionalized, quaternized polyhedral oligomeric silsesquioxane (POSS) surfactants. The octa(3‐chloropropyl) polyhedral oligomeric silsesquioxane was prepared by hydrolytic condensation of 3‐chloropropyltrimethoxysilane, which was subsequently quaternized with 2‐dimethylaminoethanol. Montmorillonite was modified with the quaternized surfactants by cation exchange reaction. Bulk polymerization of ε‐caprolactone was conducted at 110°C using stannous octoate as an initiator/catalyst. Nanocomposites were analyzed by X‐ray diffraction, transmission electron microscopy, thermo gravimetric analysis, and differential scanning calorimetry. Hydroxyl functionalized POSS was employed as a surface modifier for clay which gives stable clay separation for its 3‐D structure and also facilitates the miscibility of polymer with clay in the nanocomposites due to the star architecture. An improvement in the thermal stability of PCL was observed even at 1 wt % of clay loading. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Novel semisynthetic method for generating full length β‐amyloid peptides
Authors: Bockhorn Jessica J. , Lazar Kristi L. , Gasser Adam J. , Luther Laura M. , Qahwash Isam M. , Chopra Neeraj , Meredith Stephen C.
Published: July 2010

Bacterial expression of full length β‐amyloid (Aβ) is problematic because of toxicity and poor solubility of the expressed protein, and a strong tendency of Met35 to become oxidized in inclusion bodies. We have developed a semisynthetic method in which Aβ1‐29 is expressed in bacteria as part of a fusion protein with a C‐terminal intein and Chitin‐Binding Domain (CBD). There is also a single residue, N‐terminal Met extension. The protein, Met‐Aβ1‐29‐Intein‐CBD, is well expressed and highly water‐soluble. After binding of the expressed protein to Chitin beads, treatment with sodium 2‐mercapto‐ethane sulfonate (MESNA) yields Met‐Aβ1‐29‐MESNA, with a C‐terminal thioester suitable for native chemical ligation. Met‐Aβ1‐29‐MESNA is first subjected to CNBr cleavage, which removes the N‐terminal Met residue, but leaves the thioester intact. We synthesized NH2‐A30C‐Aβ30‐40, which has an N‐terminal Cys residue and is the partner for native chemical ligation with Met‐Aβ1‐29‐MESNA. Native chemical ligation proceeds rapidly and efficiently (>90% yield) to give A30C‐Aβ1‐40. The final step is selective desulfurization using Raney‐Ni, which also proceeds rapidly and efficiently (>90% yield) to give native sequence Aβ1‐40. Overall, this system is highly efficient, and can yield ≈8–10 mg of pure Aβ1‐40 from one liter of bacterial culture medium. This procedure is adaptable for producing other Aβ peptides. We have also expressed an Aβ construct bearing a point mutation associated with one type of familial Alzheimer's Disease, the Iowa mutation, i.e., Met‐D23N‐Aβ1‐29‐Intein‐CBD. Since expression of the intein‐containing fusion protein is robust in minimal media as well as standard enriched media, this procedure also can be readily modified for incorporating 15N or 13C labels for NMR. Future work will also include extending this system to longer Aβ peptides, such as Aβ1‐42. © 2010 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 94: 511–520, 2010.
Comparison analysis of primary ligand‐binding sites in seven‐helix membrane proteins
Authors: Pabuwal Vagmita , Li Zhijun
Published: July 2010

Seven‐helix transmembrane proteins, including the G‐protein‐coupled receptors (GPCRs), mediate a broad range of fundamental cellular activities through binding to a wide range of ligands. Understanding the structural basis for the ligand‐binding selectivity of these proteins is of significance to their structure‐based drug design. Comparison analysis of proteins' ligand‐binding sites provides a useful way to study their structure‐activity relationships. Various computational methods have been developed for the binding‐site comparison of soluble proteins. In this work, we applied this approach to the analysis of the primary ligand‐binding sites of 92 seven‐helix transmembrane proteins. Results of the studies confirmed that the binding site of bacterial rhodopsins is indeed different from all GPCRs. In the latter group, further comparison of the binding sites indicated a group of residues that could be responsible for ligand‐binding selectivity and important for structure‐based drug design. Furthermore, unexpected binding‐site dissimilarities were observed among adrenergic and adenosine receptors, suggesting that the percentage of the overall sequence identity between a target protein and a template protein alone is not sufficient for selecting the best template for homology modeling of seven‐helix membrane proteins. These results provided novel insight into the structural basis of ligand‐binding selectivity of seven‐helix membrane proteins and are of practical use to the computational modeling of these proteins. © 2010 Wiley Periodicals, Inc. Biopolymers 95: 31–38, 2011.
Correlation between anatomical characteristics of ethanol organosolv pretreated Buddleja davidii and its enzymatic conversion to glucose
Authors: Hallac Bassem B. , Ray Michael , Murphy Richard J. , Ragauskas Arthur J.
Published: July 2010

Buddleja davidii is a unique biomass that has many attractive agroenergy features, especially its wide range of growth habitat. The anatomical characteristics of B. davidii were investigated before and after ethanol organosolv pretreatment (one of the leading pretreatment technologies) in order to further understand the alterations that occur to the cellular structure of the biomass which can then be correlated with its enzymatic digestibility. Results showed that the ethanol organosolv pretreatment of B. davidii selectively removes lignin from the middle lamella (ML), which does not significantly disrupt the crystalline structure of cellulose. The removal of ML lignin is a major factor in enhancing enzymatic cellulose‐to‐glucose hydrolysis. The pretreatment also causes cell deformation, resulting in cracks and breaks in the cell wall. These observations, together with characterization analysis of the cell wall polymer material, lend support to the hypothesis that the physical distribution of lignin in the biomass matrix is an important structural feature affecting biomass enzymatic digestibility. Biotechnol. Bioeng. 2010;107: 795–801. © 2010 Wiley Periodicals, Inc.
Recreating the perivascular niche ex vivo using a microfluidic approach
Authors: Carrion Bita , Huang Carlos P. , Ghajar Cyrus M. , Kachgal Suraj , Kniazeva Ekaterina , Jeon Noo Li , Putnam Andrew J.
Published: July 2010

Stem cell niches are composed of numerous microenvironmental features, including soluble and insoluble factors, cues from other cells, and the extracellular matrix (ECM), which collectively serve to maintain stem cell quiescence and promote their ability to support tissue homeostasis. A hallmark of many adult stem cell niches is their proximity to the vasculature in vivo, a feature common to neural stem cells, mesenchymal stem cells (MSCs) from bone marrow and adipose tissue, hematopoietic stem cells, and many tumor stem cells. In this study, we describe a novel 3D microfluidic device (MFD) as a model system in which to study the molecular regulation of perivascular stem cell niches. Endothelial cells (ECs) suspended within 3D fibrin gels patterned in the device adjacent to stromal cells (either fibroblasts or bone marrow‐derived MSCs) executed a morphogenetic process akin to vasculogenesis, forming a primitive vascular plexus and maturing into a robust capillary network with hollow well‐defined lumens. Both MSCs and fibroblasts formed pericytic associations with the ECs but promoted capillary morphogenesis with distinct kinetics. Biochemical assays within the niche revealed that the perivascular association of MSCs required interaction between their α6β1 integrin receptor and EC‐deposited laminin. These studies demonstrate the potential of this physiologically relevant ex vivo model system to study how proximity to blood vessels may influence stem cell multipotency. Biotechnol. Bioeng. 2010;107: 1020–1028. © 2010 Wiley Periodicals, Inc.
Glycosyltransferases and their Assays
Authors: Wagner Gerd K. , Pesnot Thomas
Published: July 2010

Glycosyltransferases (GTs) are a large family of enzymes that are essential in all domains of life for the biosynthesis of complex carbohydrates and glycoconjugates. GTs catalyse the transfer of a sugar from a glycosyl donor to a variety of acceptor molecules, for example, oligosaccharides, peptides, lipids or small molecules. Such glycosylation reactions are central to many fundamental biological processes, including cellular adhesion, cell signalling and bacterial‐ and plant‐cell‐wall biosynthesis. GTs are therefore of significant interest as molecular targets in chemical biology and drug discovery. In addition, GTs have found wide application as synthetic tools for the preparation of complex carbohydrates and glycoconjugates. In order to exploit the potential of GTs both as molecular targets and synthetic tools, robust and operationally simple bioassays are essential, especially as more and more protein sequences with putative GT activity but unknown biochemical function are being identified. In this minireview, we give a brief introduction to GT biochemistry and biology. We outline the relevance of GTs for medicinal chemistry and chemical biology, and describe selected examples for recently developed GT bioassays, with a particular emphasis on fluorescence‐based formats.
Telomerization of Myrcene and Catalyst Separation by Thermomorphic Solvent Systems
Authors: Behr Arno , Johnen Leif , Vorholt Andreas J.
Published: July 2010

Telomerization of common petrochemical 1,3‐dienes such as butadiene and isoprene have long been successful with different nucleophiles; however, the telomerization of the C10 hydrocarbon myrcene was not known until now. Herein, the first telomerization of the monoterpene myrcene with diethylamine is discussed, which provides an atom‐economical way of generating C20 amines in a single step. Variation of the palladium precursors and phosphorous ligands and optimization of solvent and additives led to the optimum catalyst system [Pd(MeCN)4](BF4)2/PPh3. By using a thermomorphic solvent system, the Pd complex can be easily separated with low leaching values.
ChemInform Abstract: Synthesis and Characterizations of Two Anhydrous Metal Borophosphates: M2IIIBP3O12 (M: Fe, In).
Authors: Zhang Wei‐Long , Lin Chen‐Sheng , Geng Lei , Li Ye‐Yu , Zhang Hao , He Zhang‐Zhen , Cheng Wen‐Dan
Published: July 2010

The title compounds are obtained quantitatively by reacting mixtures of M2O3 (M: Fe, In), H3BO3, and NH4H2PO4 in a molar ratio of 1:1:3 at 1153 K.
ChemInform Abstract: Probing the Structure, Stability and Hydrogen Storage Properties of Calcium Dodecahydro‐closo‐dodecaborate.
Authors: Stavila Vitalie , Her Jae‐Hyuk , Zhou Wei , Hwang Son‐Jong , Kim Chul , Ottley Leigh Anna M. , Udovic Terrence J.
Published: July 2010

Compound (IV) crystallizes in the monoclinic space group C2/c with Z = 4 (powder XRD).
ChemInform Abstract: Investigation of the Structural Properties of an Extended Series of Lanthanide Bis‐hydroxychlorides Ln(OH)2Cl (Ln: Nd—Lu, Except Pm and Sm).
Authors: Zehnder Ralph A. , Clark David L. , Scott Brian L. , Donohoe Robert J. , Palmer Phillip D. , Runde Wolfgang H. , Hobart David E.
Published: July 2010

The title compounds are hydrothermally synthesized from LnCl3·6H2O in small amounts of H2O (autoclave, 220 °C, 21 d) and characterized by single crystal XRD, diffuse reflectance, FT‐IR, and FT‐Raman spectroscopy.
ChemInform Abstract: Lithium Storage Capability of Lithium Ion Conductor Li1.5Al0.5Ge1.5 (PO4)3.
Authors: Feng J. K. , Lu L. , Lai M. O.
Published: July 2010

The title compound with a NASICON structure is prepared by solid state reaction of stoichiometric amounts of Li2CO3, Al2O3, Ge, and NH4H2PO4 (Pt crucible, 700 and 950 °C, 2 h each) and characterized by XRD, cyclic voltammetry, AC impedance, DC conductivity measurements, and battery tests.
ChemInform Abstract: Synthesis, Characterization and Photocatalytic Properties of CaNb2O6 with Ellipsoid‐Like Plate Morphology.
Authors: Cho In‐Sun , Kim Dong Wook , Cho Chin Moo , An Jae‐Sul , Roh Hee‐Suk , Hong Kug Sun
Published: July 2010

Ellipsoid‐like two‐dimensional plates of the title compound are hydrothermally synthesized from EtOH solutions of Ca(NO3)2 and NbCl5 (pH 11 adjusted with NH4OH, autoclave, 200 °C, 24 h).
ChemInform Abstract: Development of a Building Block Strategy to Access Gigantic Nanoscale Heteropolyoxotungstates by Using SeO2‐3 as a Template Linker.
Authors: Yan Jun , Long De‐Liang , Cronin Leroy
Published: July 2010

Gigantic heteropolyoxotungstates are synthesized using the SeO32‐ group as both heterotemplate and linker.
ChemInform Abstract: Super Silyl Stereo‐Directing Groups for Complete 1,5‐syn and ‐anti Stereoselectivities in the Aldol Reactions of β‐Siloxy Methyl Ketones with Aldehydes.
Authors: Yamaoka Yousuke , Yamamoto Hisashi
Published: July 2010

Aldol reactions of β‐tris(trialkylsilyl)siloxy methyl ketones (I) with various aldehydes proceed in the presence of lithium hexamethyldisilazide with high syn‐selectivity.
ChemInform Abstract: Thermal Behavior of Bicyclo[2.2.2]octadiene‐Installed Precursors for 2H‐Anthra[2,3‐c]pyrroles and Anthra[2,3‐c]thiophene.
Authors: Uoyama Hiroki , Chenxin Cai , Tahara Hiroyuki , Shimizu Yusuke , Hagiwara Hideki , Hanasaki Yasuaki , Yamada Hiroko , Okujima Tetsuo , Uno Hidemitsu
Published: July 2010

4,11‐Ethano‐4,11‐dihydro‐2H‐anthra[2,3‐c]pyrroles (IV) and the corresponding thiophene (VI) are prepared, and their thermogravimetric behavior is studied.
ChemInform Abstract: Chemoselective Conjugate Reduction of α,β‐Unsaturated Ketones Catalyzed by Rhodium Amido Complexes in Aqueous Media.
Authors: Li Xuefeng , Li Liangchun , Tang Yuanfu , Zhong Ling , Cun Linfeng , Zhu Jin , Liao Jian , Deng Jingen
Published: July 2010

In the presence of HCOONa, Rh2Cl4(C5Me5)2, and the diamine (AMI) α,β‐unsaturated ketones are found to undergo reduction of the C=C double bond with high selectivity.
ChemInform Abstract: Nickel‐Catalyzed Amination of Aryl Pivalates by the Cleavage of Aryl C—O Bonds.
Authors: Shimasaki Toshiaki , Tobisu Mamoru , Chatani Naoto
Published: July 2010

The title reaction provides a new, efficient, and widely applicable method to prepare aromatic amines.
ChemInform Abstract: Straightforward Access to α‐Methylamines Through Cross‐Metathesis.
Authors: Poulhes Florent , Sylvain Remy , Perfetti Patricia , Bertrand Michele P. , Gil Gerard , Gastaldi Stephane
Published: July 2010

A two step procedure consisting of cross‐metathesis (olefins with methyl vinyl ketone) and reductive amination offers an efficient access to a variety of title compounds.
ChemInform Abstract: Reaction of Carboxylic Acids with Tetrachlorosilane.
Authors: Voronkov M. G. , Vlasov A. V. , Belousova L. I. , Grigor'eva O. Yu. , Vlasova N. N.
Published: July 2010

The reaction of carboxylic acids with SiCl4 can be recommended as a preparative route to corresponding acid chlorides only for weak acids (pKa < 4.7).
ChemInform Abstract: Catalytic Asymmetric Domino Michael—Henry Reaction: Enantioselective Access to Bicycles with Consecutive Quaternary Centers by Using Bifunctional Catalysts.
Authors: Rueping Magnus , Kuenkel Alexander , Froehlich Roland
Published: July 2010

A bifunctional, cinchonidine‐based, thiourea catalyst is shown to catalyze the enantioselective domino Michael—Henry reaction of cyclohexadienone (I) with various β‐nitrostyrenes.
ChemInform Abstract: Copper(II)‐Catalyzed Conversion of Aryl/Heteroaryl Boronic Acids, Boronates, and Trifluoroborates into the Corresponding Azides: Substrate Scope and Limitations.
Authors: Grimes Kimberly D. , Gupte Amol , Aldrich Courtney C.
Published: July 2010

A large variety of boronic acids, boronates and trifluoroborates bearing (het)aryl substituents reacts with sodium azide in the presence of Cu(OAc)2 to give the corresponding aryl azides.
ChemInform Abstract: Highly Efficient Asymmetric Three‐Component Vinylogous Mannich Reaction Catalyzed by a Chiral Scandium(III)‐N,N′‐dioxide Complex.
Authors: Zhang Qi , Hui Yonghai , Zhou Xin , Lin Lili , Liu Xiaohua , Feng Xiaoming
Published: July 2010

Various aldehydes can be converted to highly functionalized δ‐amino‐α,β‐unsaturated carboxylic esters with good to excellent enantioselectivity and complete regioselectivity.
ChemInform Abstract: A New Chemo‐Enzymatic Route to Chiral 2‐Hydroxy‐4‐phenylbutyrates by Combining Lactonase‐Mediated Resolution with Hydrogenation over Pd/C.
Authors: Chen Bing , Yin Hai‐Feng , Wang Zhen‐Sheng , Liu Jia‐Ying , Xu Jian‐He
Published: July 2010

A new chemo‐enzymatic route to both enantiomers of 2‐hydroxy‐4‐phenylbutyric acid is reported.
ChemInform Abstract: An Efficient Synthesis of Sulfamides.
Authors: Guo Chuangxing , Dong Liming , Kephart Susan , Hou Xinjun
Published: July 2010

In connection with efforts concerning the synthesis of potential FKBP‐12 inhibitors in which the known ketoamide linker is replaced by sulfamide, various target compounds are prepared.
ChemInform Abstract: Facile Preparation of Protected Benzylic and Heteroarylmethyl Amines via Room Temperature Curtius Rearrangement.
Authors: Leathen Matthew L. , Peterson Emily A.
Published: July 2010

A simple step‐wise procedure renders possible the rearrangement of a variety of carboxylic acids at room temperature.
ChemInform Abstract: Pd‐Catalyzed Decarboxylative Arylation of Thiazole, Benzoxazole, and Polyfluorobenzene with Substituted Benzoic Acids.
Authors: Xie Kai , Yang Zhiyong , Zhou Xingjian , Li Xiujian , Wang Sizhou , Tan Ze , An Xiangyu , Guo Can‐Cheng
Published: July 2010

The process allows the preparation of the target compounds with high chemo‐ and regioselectivities.
ChemInform Abstract: Palladium‐Catalyzed ortho‐Arylation of O‐Phenylcarbamates with Simple Arenes and Sodium Persulfate.
Authors: Zhao Xiaodan , Yeung Charles S. , Dong Vy M.
Published: July 2010

The present oxidative cross‐coupling reaction proceeds by a Pd(0)/Pd(II) catalytic cycle involving C—H bond activation by carbamate‐assisted cyclopalladation, C—H bond functionalization by electrophilic metalation, reductive elimination and reoxidation of Pd(0).
ChemInform Abstract: Water‐Soluble Palladium and Gold Nanoparticles Functionalized by a New Phosphine with Zwitterionic Liquid Based on Imidazolium Sulfonate Linked Ethylene Glycol Moiety.
Authors: Akiyama Taichi , Ibata Chiharu , Fujihara Hisashi
Published: July 2010

The new phosphine (PHOS) is used to prepare stable metal nanoparticles in aqueous electrolyte.
ChemInform Abstract: Boron Trichloride Mediated Alkyne‐Aldehyde Coupling Reactions.
Authors: Yao Min‐Liang , Quinn Michael P. , Kabalka George W.
Published: July 2010

The mechanism of the coupling reaction of aldehyde (I), phenylacetylene (II) and BCl3 is investigated.
ChemInform Abstract: Enantioselective Synthesis of Bicarbocyclic Structures with an All‐Carbon Quaternary Stereocenter Through Sequential Cross Metathesis and Intramolecular Rauhut—Currier Reaction.
Authors: Qiao Yuan , Kumar Sanjeev , Malachowski William P.
Published: July 2010

A process consisting of Ru‐catalyzed cross‐coupling and an intramolecular Rauhut—Currier reaction is described to construct highly functionalized hydrindan skeletons containing an all‐carbon quaternary stereocenter in an angular position.
ChemInform Abstract: Regioselective and Stereoselective Cyclizations of Chloropolyols in Water: Rapid Synthesis of Hydroxytetrahydrofurans.
Authors: Kang Baldip , Chang Stanley , Decker Shannon , Britton Robert
Published: July 2010

A wide range of the sterically defined mono‐, tri‐ and tetrasubstituted tetrahydrofurans is prepared in a simple microwave‐assisted reaction in water without any additives.
ChemInform Abstract: Expeditious Synthesis of Benzopyrans via Lewis Acid‐Catalyzed C—H Functionalization: Remarkable Enhancement of Reactivity by an ortho Substituent.
Authors: Mori Keiji , Kawasaki Taro , Sueoka Shosaku , Akiyama Takahiko
Published: July 2010

ortho‐Substitution to the alkoxy group enhances the reactivity of the substrates and leads to the higher yields of the corresponding products [cf.
ChemInform Abstract: Improved Procedure for the Enantioselective Synthesis of Dihydrooxazolo and Dihydrothiazolo Ring‐Fused 2‐Pyridones.
Authors: Chorell Erik , Edvinsson Sofie , Almqvist Fredrik
Published: July 2010

The synthesis includes dehydrative cyclization of serine derivatives (I) and condensation of the resulting oxazolines with Meldrum′s acid derivative (II).
ChemInform Abstract: Furan Ring Recyclization in 2‐Furfurylthieno[2,3‐b]pyridines: An Intramolecular N‐Alkylation of Pyrrole Ring under Acid Conditions.
Authors: Kosulina Darya Yu. , Vasilin Vladimir K. , Stroganova Tatyana A. , Kaklyugina Tatyana Ya. , Krapivin Gennady D.
Published: July 2010

Depending on reaction conditions, the new heterocycles (V) and (VII) are formed from the 4‐unsubstituted derivative (IVa).
ChemInform Abstract: Four‐Component Domino Reaction Providing an Easy Access to Multifunctionalized Tricyclo[6.2.2.01.6]dodecane Derivatives.
Authors: Jiang Bo , Li Chao , Shi Feng , Tu Shu‐Jiang , Kaur Parminder , Wever Walter , Li Guigen
Published: July 2010

The reaction proceeds with complete control of stereoselectivity.
ChemInform Abstract: Acid‐Induced Rearrangement Reactions of α‐Hydroxy‐1,3‐dithianes.
Authors: Krohn Karsten , Cludius‐Brandt Stephan
Published: July 2010

The reactions include rearrangements, water elimination or deoxygenation.
ChemInform Abstract: Efficient Synthesis of Benzimidazo[1,2‐a]pyrimidinone Derivatives via Catalyst‐Free Reactions of Baylis—Hillman Acetates, Alcohols, and Amines with 2‐Aminobenzimidazole.
Authors: Wang Yan , Shafiq Zahid , Liu Li , Wang Dong , Chen Yong‐Jun
Published: July 2010

The title compounds, e.g. (III) and (V), are prepared by an efficient and facile one‐pot process without the use of any catalyst or additive.
ChemInform Abstract: Rumphellclovane A, a Novel Clovane‐Related Sesquiterpenoid from the Gorgonian Coral Rumphella antipathies.
Authors: Chung Hsu‐Ming , Chen Yung‐Husan , Hwang Tsong‐Long , Chuang Li‐Fan , Wan Wei‐Hsien , Sung Ping‐Jyun
Published: July 2010

Title compound A (I) and (II) is isolated together with the natural clovane 2β‐hydroxyclovan‐9‐one (II).
ChemInform Abstract: Phase‐Transfer Catalyzed Enantioselective Epoxidation of Estra‐Λ5(10),9(11)‐diene Using Chiral Ammonium Salts Derived from Cinchona Alkaloids.
Authors: Yang Ya‐Xi , Li Zheng , Chen Guo‐Rong , Li Yuan‐Chao
Published: July 2010

A series of chiral ammonium salts derived from cinchona alkaloids is synthesized and used as phase‐transfer catalyst to improve the epoxidation of title compound (I).
ChemInform Abstract: Studies in Synthesis of New Psoralenamines.
Authors: Patel Jagdish M. , Soman Shubhangi S.
Published: July 2010

Starting from the known brominated β‐methyl umbelliferone (I), a pathway to several novel psoralenamines (VI) is described.
ChemInform Abstract: Some Remarks on Substitution Effects in Sodalites
Authors: Peters Lars , Vega‐Flores Greys , Depmeier Wulf
Published: July 2010

Review: 43 refs.
ChemInform Abstract: Surface‐Mediated Organometallic Syntheses
Authors: Cariati Elena , Dragonetti Claudia , Lucenti Elena , Roberto Dominique , Ugo Renato
Published: July 2010

Review: 153 refs.
ChemInform Abstract: Cinchona‐Catalyzed Nucleophilic 1,2‐Addition to C—O and C‐N Double Bonds
Authors: Jang Hyeong Bin , Lee Ji Woong , Song Choong Eui
Published: July 2010

Review: 110 refs.
ChemInform Abstract: Cinchona‐Based Organocatalysts for Asymmetric Oxidations and Reductions
Authors: Shin Ueon Sang , Lee Je Eun , Yang Jung Woon , Song Choong Eui
Published: July 2010

Review: 54 refs.
ChemInform Abstract: The Chemistry of Superbasic Guanidines
Authors: Sundermeyer Joerg , Raab Volker , Gaoutchenova Ekatarina , Garrelts Udo , Abacilar Nuri , Harms Klaus
Published: July 2010

Review: 51 refs.
ChemInform Abstract: Solid‐State Electrochemiluminescence Analysis with Co‐Reactant of the Immobilized Tris(2,2′‐bipyridyl) Ruthenium
Authors: Su Ming , Liu Songqin
Published: July 2010

Review: 128 refs.
ChemInform Abstract: Modeling Copper Binding to the Amyloid‐β Peptide in Alzheimer′s Disease.
Authors: Epa V. Chandana , Streltsov Victor A. , Varghese Joseph N.
Published: July 2010

Review: 44 refs.
ChemInform Abstract: 5′‐Nucleotidases and Their New Roles in NAD+ and Phosphate Metabolism
Authors: Bogan Katrina L. , Brenner Charles
Published: July 2010

Review: 103 refs.
ChemInform Abstract: Amino Acids, Peptides, and Proteins: CE Analysis
Authors: Corradini Danilo
Published: July 2010

Review: 15 refs.
Osteosarcoma in very young children
Authors: Kager Leo , Zoubek Andreas , Dominkus Martin , Lang Susanna , Bodmer Nicole , Jundt Gernot , Klingebiel Thomas , Jürgens Heribert , Gadner Helmut , Bielack Stefan ,   for the COSS Study Group
Published: July 2010

BACKGROUND:

This study was conducted to investigate presentation, treatment, and outcome in very young children with osteosarcoma.

METHODS:

The authors retrospectively analyzed the data of 2706 consecutive COSS patients with newly diagnosed osteosarcoma and identified 28 (1.0%) patients aged younger than 5 years at diagnosis. Demographic, diagnostic, tumor, treatment‐related variables, response, and survival data were analyzed.

RESULTS:

Of the 28 preschoolers, 27 presented with high‐grade central osteosarcoma of an extremity, and 1 had a secondary osteosarcoma of the orbit. This analysis focused on the 27 patients with extremity tumors. The size of the primary was large (≥one‐third of the involved bone) in 20 of 27 patients. Primary metastases were detected in 4 of 27 children. All patients received multiagent chemotherapy, and 11 of 18 analyzed tumors responded well (>90% necrosis) to neoadjuvant chemotherapy. Limb‐sparing surgery was performed in 9 cases, ablative procedures were performed in 15, and, in 3 cases, no local surgery was performed. With a median follow‐up of 4 years (6.2 years for survivors), 13 patients were alive. Four patients never achieved a complete remission, and 11 developed recurrences; 14 of these 15 patients died. Five‐year overall and event‐free survival probabilities were 51% (standard error of the mean [SE], 10%) and 48% (SE, 10%). Better survival was correlated with good response to chemotherapy and later time period of diagnosis.

CONCLUSIONS:

Osteosarcoma is extremely rare in preschool children. These patients often have large tumors that may require mutilating resections. Prognosis is in the range of that reported for older patients. Cancer 2010. © 2010 American Cancer Society.
Dysembryoplastic neuroepithelial tumors and cognitive outcome
Authors: Qaddoumi Ibrahim , Ellison David W. , Morris E. Brannon , Broniscer Alberto , Boop Frederick , Merchant Thomas , Palmer Shawna L. , Gajjar Amar
Published: July 2010

BACKGROUND:

Dysembryoplastic neuroepithelial tumors (DNETs) are benign glioneuronal tumors that occur in children. These tumors are characterized by seizures, lack of neurologic deficits, and a seemingly benign course after resection.

METHODS:

A retrospective review was conducted of data relating to 11 children diagnosed with DNETs between January 1988 and December 2007 at St. Jude Children's Research Hospital. This report documented the clinical features, neurocognitive function, and treatment outcomes in this institutional series.

RESULTS:

The patient cohort included 8 boys and 3 girls (median age at diagnosis, 10 years); all patients presented with seizures: 4 complex partial, 3 generalized tonic‐clonic, 2 absence, 1 partial simple, and 1 not classified. Of the 11 patients, 1 died of cardiac fibrosis, and tumors recurred or progressed in 4 (36%) patients. Seizure control was achieved in all patients but 1. Of the 9 patients who completed neuropsychologic testing, only 3 (33%) functioned at or above the expected level of same‐age peers.

CONCLUSIONS:

The high recurrence and progression rates of DNETs and the high rate of abnormal neurocognitive test results noted in the current study highlight the need for regular follow‐up and appropriate academic counseling of children with these tumors. Cancer 2010. © 2010 American Cancer Society
Cancer incidence in the multicenter aids cohort study before and during the HAART era
Authors: Seaberg Eric C. , Wiley Dorothy , Martínez‐Maza Otoniel , Chmiel Joan S. , Kingsley Lawrence , Tang Yiwei , Margolick Joseph B. , Jacobson Lisa P. ,   for the Multicenter AIDS Cohort Study (MACS)
Published: July 2010

BACKGROUND:

The incidence of Kaposi sarcoma (KS) and non‐Hodgkin lymphoma (NHL) among human immunodeficiency virus (HIV)‐infected individuals declined after the introduction of highly active antiretroviral therapy (HAART) in the mid‐1990s, but the cancer risk associated with HIV infection during the HAART era remains to be clarified.

METHODS:

Cancer incidence among HIV‐infected and HIV‐uninfected participants in the Multicenter AIDS (acquired immunodeficiency syndrome) Cohort Study (MACS) between 1984 and 2007 was compared with the expected incidence using US population‐based data from the Surveillance, Epidemiology, and End Results (SEER) program. Age‐ and race‐adjusted cancer incidence rates were also compared HIV by status and over time within the MACS. Exact statistical methods were used for all analyses.

RESULTS:

A total of 933 incident cancers were observed during 77,320 person‐years of follow‐up. Compared with SEER, MACS HIV‐infected men had significantly (P < .05) elevated rates of KS (standardized incidence ratio [SIR], 139.10), NHL (SIR, 36.80), Hodgkin lymphoma (HL)(SIR, 7.30), and anal cancer (SIR, 25.71). Within MACS, HIV infection was found to be independently associated with each of these cancers across the entire follow‐up period, and KS (incidence rate ratio [IRR], 54.93), NHL (IRR, 11.18), and anal cancer (IRR, 18.50) were each found to be significantly elevated among HIV‐infected men during the HAART era. Among these men, the incidence of KS and NHL declined (IRR, 0.13 and 0.23, respectively), the incidence of anal cancer increased (IRR, 5.84), and the incidence of HL remained statistically unchanged (IRR, 0.75) from the pre‐HAART to the HAART era.

CONCLUSIONS:

Cancer risk remains elevated among HIV‐infected men who have sex with men, highlighting the continuing need for appropriate cancer screening in this population. Cancer 2010. © 2010 American Cancer Society.