bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemie und Biochemie der Pflanzenstoffe, XXII1) 6‐ und 7‐substituierte 1.4‐Dioxo‐isochromane
Authors: Reichel Ludwig , Hampel Winfried 
Published: December 2009

Abstract6‐ und 7‐substituierte 1.4‐Dioxo‐isochromane (4a – f) werden aus 4‐substituierten Phthalsäureanhydriden (1a‐‐f) über die Monomethylester. Säurechloride und Diazomethylketone dargestellt. Die Reaktion von 4‐Halogen‐phthalsäureanhydriden mit absol. Methanol führt bevorzugt zu 2‐Methoxycarbonyl‐4‐halogen‐benzoesäuren (5a–d). 4‐Halogen‐homophthalsäuren (9a und b) b) werden synthetisiert und zum Konstitutionsbeweis von 5a – herangezogen. 4‐Methoxy‐phthalsäureanhydrid (1e) liefert mit absol. Methanol ebenfalls überwiegend den 2‐Monomethylester 5e.
Zur Kenntnis der Proanthocyanidine, XI1) Konfigurationsbestimmung von C30H26O12‐Procyanidinen und Strukturaufklärung eines neuen Procyanidins
Authors: Weinges Klaus , Göritz Klaus , Nader Franz 
Published: December 2009

AbstractMit Hilfe der NMR‐Spektren werden 4 diastereomeren Decaacetyl‐procyanidinen B1–B4 die Konfigurationen 4–7 zugeordnet. Ein Procyanidin der Summenformel C30H26O11 wird aus den Hülsen der Glyzinie (Wistaria sinensis) isoliert; seine Konstitution 2 und die Konfiguration 8 seines Nonaacetats ergeben sich massenspektrometrisch und durch Vergleich mit dem NMR‐Spektrum von 7.
Zuckerperoxide IV1) Darstellung, Reaktionen und NMR‐Untersuchungen von Zucker‐1.2‐peroxyorthoestern2)
Authors: Schulz Manfred , Boeden Hans‐Friedrich , Berlin Peter , Bley Wolf‐Rüdiger 
Published: December 2009

AbstractDie Synthese der acetylierten 1.2‐tert.‐Butylperoxyrothoacetate von D‐Glucose, D‐Galaktose, D‐Mannose, L‐Rhamnose und D‐Xylose sowie der benzoylierten 1.2‐tert.‐Butylperoxyorthobenzoate von pyranoider und furanoider L‐Arabinose wird beschrieben (Tab. 1). Die durch Entacetylierung der Verbindungen erhaltenen Zucker‐1.2.‐tert.‐butyl‐peroxyrothoester (Tab. 2) mit freien Hydroxylgruppen sind kristallin. Mit wasserfreien Säuren lagern sich die acylierten tert.‐Butylperoxyorthoester zu acylierten Peroxyglykosiden um (Tab. 3). Aus den Ergebnissen von NMR‐Untersuchungen der acylierten Zucker‐1.2‐tert.‐butylperoxyorthoester werden mit den Kopplungskonstanten (Tab. 4) unter Voraussetzung der Gültigkeit der Karplus‐Beziehung und mit Hilfe von Dreiding‐Modellen Konformationen abgeleitet: für das D‐Glucose‐ und das D‐Xylose‐Derivat (3 bzw. 7) einen verzerrte Wanne, für das D‐Galaktose‐,D‐Mannose‐ bzw. L‐Rhamnose‐Derivat (5 bzw. 11 bzw. 13) ein verzerrter Sessel.
Darstellung von abeo‐ und diabeo‐Steroiden, II1)
Authors: Snatzke Günther , Nising Wolfgang 
Published: December 2009

AbstractAus 3α‐Acetoxy‐Δ8‐5β‐cholensäure‐methylester (1) werden durch RuO4‐Oxydation, Kondensation, erneute Doppelbindungssprengung und Kondensation die beiden an C‐14 epimeren 3α‐Acetoxy‐9(8→7).8(9→11)‐diabeo→7(11)‐5β‐cholen‐8.9‐dionsäure‐methylester (11 und 12), zwei Linearanaloge der Steroid‐Reihe, hergestellt. Als Nebenprodukte der Oxydation von 1 entstehen das 8α.9α‐Glykol 3 und das 9β‐Hydroxy‐8β‐epoxid 4. Aus dem Δ8‐En‐7.11‐dion 14 erhält man mit RuO4 unter anderem das 8α.9α‐Epoxid 15.
Kinetik der Spaltung von N‐Schutzgruppen Aminosäure‐phenacylestern
Authors: Losse Günter , Berndsen Gunda 
Published: December 2009

AbstractDie Hydrogenolyse N‐geschützter Aminosäure‐phenacylester und ihre Spaltung mit Natriumthiophenolat werden am Modell Hippursäure in Abhängigkeit von Substituenten an der Phenacyl‐Gruppe kinetisch verfolgt. Anwendungsmöglichkeiten der gefundenen Reaktivitätsdifferenzen für die selektive Entblockierung von Carboxylgruppen bei Peptid‐Synthesen werden erörtert.
Zur Chemie derp‐Chinole, XI1). Neue Östratriene mit verschiedenen Stickstoff‐Funktionen in 3‐Stellung
Authors: Traut Martin , Hecker Erich 
Published: December 2009

Abstractp‐Chinole undp‐Chinolacetate lassen sich mit Hydroxylamin zu Abkömmlingen des Nitrosobenzols aromatisieren. Auf diesem Wege erhält manp‐Nitroso‐toluol, 6‐Nitroso‐tetralin (2f) und 3‐Nitroso‐Δ1.3.5(10)‐östratrien (1f), das auch aus dem Amin1aüber 3‐Nitro‐Δ1.3.5(10)‐östratrien (1e) dargestellt wird. Analog entsteht 2‐Nitroso‐fluoren aus 2‐Nitro‐fluoren. Die Nitrosoverbindungen sind grüne Monomere; 2‐Nitroso‐fluoren und 3‐Nitroso‐Δ1.3.5(10)‐östratrien zeigen im ESR‐Spektrum einen geringfügigen Radikal‐Gehalt. Nitrosoverbindungen und Hydroxylamin‐Abkömmlinge sind möglicherweise Wirkformen entsprechender carcinogener Amine.
A facile and efficient synthesis of d6‐labeled PU‐H71, a purine‐scaffold Hsp90 inhibitor
Authors: Taldone Tony , Zatorska Danuta , Kang Yanlong , Chiosis Gabriela 
Published: December 2009

AbstractPU‐H71 is a purine‐scaffold Hsp90 inhibitor currently undergoing late stage preclinical evaluation for the treatment of cancer. In this investigation, we present a simple method for the synthesis of d6‐labeled PU‐H71 for use as an internal standard to accurately quantitate the drug in biological matrices based on an LC‐MS‐MS method. PU‐H71‐d6 was synthesized in five steps using readily available 1,3‐dibromopropane‐d6 and is an important compound for the advancement of our clinical program. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of tritium‐labeled (R,R)‐4‐methoxyfenoterol
Authors: Kozocas Joseph A. , Bupp James E. , Tanga Mary J. , Pluhar Joseph T. , Wainer Irving W. 
Published: December 2009

AbstractThe preparation of 2′,4′,6′‐[3H3]‐(R,R)‐4‐methoxyfenoterol, a tritium‐labeled derivative of (R,R)‐4‐methoxyfenoterol was demonstrated on a 15 mCi scale providing material with a specific activity of 57 Ci/mmol. Copyright © 2009 John Wiley & Sons, Ltd.
Anxiety sensitivity and posttrauma stress symptoms in female undergraduates following a campus shooting
Authors: Stephenson Katherine L. , Valentiner David P. , Kumpula Mandy J. , Orcutt Holly K. 
Published: December 2009

AbstractParticipants were recruited from female undergraduate students participating in an ongoing longitudinal study at the time of a campus shooting. Eighty‐five percent (N = 691) of the 812 students who were invited to participate in the current study completed questionnaires an average of 27 days following a campus shooting. In a mixed cross‐sectional and longitudinal design, the cognitive and the physical concerns dimensions of postshooting anxiety sensitivity accounted for unique variance in posttrauma stress symptom severity (cross‐sectional), after controlling for preshooting psychological symptoms (longitudinal). The cognitive concerns dimension showed the strongest relationship. Anxiety sensitivity also appeared to moderate the relationships of hyperarousal symptoms with reexperiencing and numbing symptoms.
The influence of news events on health after disaster: A longitudinal study in general practice
Authors: ten Veen Petra M.H. , Morren Mattijn , Yzermans C. Joris 
Published: December 2009

AbstractThis study investigates the influence of local and international news events on utilization of health services resources and health complaints as presented by victims of a fireworks depot disaster. It was hypothesized that victims (N = 2,854) will show more utilization and health complaints to their general practitioner (GP) in the week after 11 local news reports of events relating to the specific index trauma and 6 unrelated disasters reported in international print news, than the week before. Health data of victims and matched controls were extracted from electronic medical records, covering 4‐years postdisaster. Especially local news events concerning the cause of the disaster were associated in both victims and controls with an increase of GP utilization and health complaints, including medically unexplained physical symptoms, chronic diseases, and psychological problems. No difference between victims and controls were found.
Sleep disturbance and baroreceptor sensitivity in women with posttraumatic stress disorder
Authors: Ulmer Christi S. , Calhoun Patrick S. , Edinger Jack D. , Wagner H. Ryan , Beckham Jean C. 
Published: December 2009

AbstractIn a previous study, women with posttraumatic stress disorder (PTSD) had greater objective sleep disturbance than those without PTSD. In a separate previous study, women with PTSD were also found to have lower baroreceptor sensitivity (BRS), an index of blood pressure regulation. In the present study, the authors concurrently assessed BRS and objective sleep by diagnostic status. A comparison of 32 women with PTSD with 21 women without PTSD revealed an interaction between BRS and sleep efficiency, wake after sleep onset percentage, and sleep fragmentation. Lower BRS was associated with poorer sleep in women with PTSD, but not in those without. Future research should investigate causal relationships between sleep and blood pressure regulation in those with PTSD.
Poly(vinyl phosphonic acid): Hydrodynamic Properties and SEC‐Calibration in Aqueous Solution
Authors: Strandberg Clara , Rosenauer Christine , Wegner Gerhard 
Published: December 2009

AbstractPoly(vinyl phosphonic acid) (PVPA) as obtained by free radical polymerization of aqueous vinyl phosphonic acid was studied by light scattering (SLS, DLS) and size exclusion chromatography (SEC) in dilute aqueous solutions containing sufficient salt in order to screen long range electrostatic interactions. Samples of 37<$\overline M _{\rm w}$< 110 × 103were studied. The polymers showed positiveA2‐values in aqueous NaH2PO4solution (0.04 M), and self‐diffusion behavior and RH/RG—ratios indicative of the structure of random coiled chains. A comparison of the SEC‐elugrams of the PVPA‐samples with those of commercially available standards of poly(acrylic acid) sodium salt gave a fit to the same calibration curve described by logPn(PVPA) = −0.21νe + 7.0(+0.1) which correlates the number average degree of polymerization (Pn) with the elution volumeνe. This indicates that PVPA and PAA have the same hydrodynamic structure under given solution conditions.magnified image
Gold Nanoparticles Functionalized by a Dextran‐Based pH‐ and Temperature‐Sensitive Polymer
Authors: Lv Weipeng , Liu Shuoqi , Fan Xiaobin , Wang Shulan , Zhang Guoliang , Zhang Fengbao 
Published: December 2009

AbstractA dextran‐based dual‐sensitive polymer is employed to endow gold nanoparticles with stability and pH‐ and temperature‐sensitivity. The dual‐sensitive polymer is prepared by RAFT polymerization of N‐isopropylacrylamide from trithiocarbonate groups linked to dextran and succinoylation of dextran after polymerization. The functionalized nanoparticles show excellent stability under various conditions and can be stored in powder‐form. UV and DLS measurements confirm that the temperature‐induced optical changes and aggregation behaviors of the particles are strongly dependent on pH.magnified image
Direct Structuring of a Biomimetic Anti‐Reflective, Self‐Cleaning Surface for Light Harvesting in Organic Solar Cells
Authors: Choi Se‐Jin , Huh Sung‐Yoon 
Published: December 2009

AbstractA one‐step method to fabricate a biomimetic dual‐scale hierarchical structure for a transparent anti‐reflective, self‐cleaning layer for organic solar cells is reported. Template‐mediated UV replica molding is used to directly create a multi‐functional surface with an acrylate‐functionalized perfluoropolyether without complicated processing steps. The surface exhibits superhydrophobic properties and self‐cleaning characteristics. In addition, the surface leads to an enhancement of photovoltaic power conversion efficiency by ≈10% as a result of reflection suppression and transmittance enhancement. The method can easily be applied to large area substrates (22 cm × 24 cm) in a cost‐effective manner. Furthermore, the solar cell can withstand harsh outdoor conditions for a long time, without a notable change in the device performance, owing to robust surface layer and non‐fouling properties.magnified image
Self‐Complementary Nucleoside‐Thiophene Hybrid Systems: Synthesis and Supramolecular Organization
Authors: Navacchia Maria Luisa , Favaretto Laura , Treossi Emanuele , Palermo Vincenzo , Barbarella Giovanna 
Published: December 2009

AbstractVersatile synthetic methods towards a variety of thiophene‐nucleobase hybrid systems are reported. Adenine‐ and thymine‐based modified nucleosides characterized by a bithiophene unit linked to the C5′ or C8 position through an ethylenamino or an ethylensulfanyl bridge were synthesized and successfully polymerized in the presence of FeCl3. The self‐organization properties of the pure polymers as well as their mixtures ‐ with complementary nucleobases ‐ were investigated by means of optical microscopy and AFM in cast film showing complex supramolecular structures resulting from the interplay of multiple intermolecular interactions.magnified image
Angiostatic effects of Brazilian green propolis and its chemical constituents
Authors: Chikaraishi Yuichi , Izuta Hiroshi , Shimazawa Masamitsu , Mishima Satoshi , Hara Hideaki 
Published: December 2009

AbstractPropolis, a resinous substance collected by honeybees from various plant sources, has several pharmacological actions, such as anti‐tumor and anti‐inflammatory effects. The aim of this study was to evaluate the anti‐angiogenic effects of a water extract of Brazilian green propolis (WEP) and its constituents, caffeoylquinic acid derivatives, against angiogenic processes in human umbilical vein endothelial cells (HUVECs) in vitro. We also examined the anti‐angiogenic effects of WEP against retinal neovascularization in a murine oxygen‐induced retinopathy model in vivo. WEP and its constituents significantly suppressed vascular endothelial growth factor (VEGF)‐induced HUVEC proliferation, migration, and tube formation in vitro. WEP and its caffeoylquinic acid derivatives suppressed VEGF‐stimulated phosphorylation of mitogen‐activated protein kinase in HUVECs (versus VEGF alone). Moreover, WEP (300 mg/kg/day, subcutaneously for 5 days) significantly suppressed retinal neovascularization in the murine oxygen‐induced retinopathy model. These data indicate that (i) WEP has angiostatic effects against angiogenic processes in vitro and in an in vivo model of murine oxygen‐induced retinopathy and (ii) the inhibitory effects of WEP against in vitro angiogenesis are chiefly derived from its caffeoylquinic acid derivatives. Judging from these findings, WEP and its caffeoylquinic acid derivatives may represent candidates for preventive or therapeutic agents against diseases caused by angiogenesis.
Supplementation with the reduced form of Coenzyme Q10 decelerates phenotypic characteristics of senescence and induces a peroxisome proliferator‐activated receptor‐α gene expression signature in SAMP1 mice
Authors: Schmelzer Constance , Kubo Hiroshi , Mori Masayuki , Sawashita Jinko , Kitano Mitsuaki , Hosoe Kazunori , Boomgaarden Inka , Döring Frank , Higuchi Keiichi 
Published: December 2009

AbstractOur present study reveals significant decelerating effects on senescence processes in middle‐aged SAMP1 mice supplemented for 6 or 14 months with the reduced form (Q10H2, 500 mg/kg BW/day) of coenzyme Q10 (CoQ10). To unravel molecular mechanisms of these CoQ10 effects, a genome‐wide transcript profiling in liver, heart, brain and kidney of SAMP1 mice supplemented with the reduced (Q10H2) or oxidized form of CoQ10 (Q10) was performed. Liver seems to be the main target tissue of CoQ10 intervention, followed by kidney, heart and brain. Stringent evaluation of the resulting data revealed that Q10H2 has a stronger impact on gene expression than Q10, primarily due to differences in the bioavailability. Indeed, Q10H2 supplementation was more effective than Q10 to increase levels of CoQ10 in the liver of SAMP1 mice. To identify functional and regulatory connections of the “top 50” (p<0.05) Q10H2‐sensitive transcripts in liver, text mining analysis was used. Hereby, we identified Q10H2‐sensitive genes which are regulated by peroxisome proliferator‐activated receptor‐α and are primarily involved in cholesterol synthesis (e.g. HMGCS1, HMGCL and HMGCR), fat assimilation (FABP5), lipoprotein metabolism (PLTP) and inflammation (STAT‐1). These data may explain, at least in part, the decelerating effects on degenerative processes observed in Q10H2‐supplemented SAMP1 mice.
Hypolipidemic effects of proanthocyanidins and their underlying biochemical and molecular mechanisms
Authors: Bladé Cinta , Arola Lluis , Salvadó Maria‐Josepa 
Published: December 2009

AbstractProanthocyanidins are the most abundant polyphenols in human diets. Epidemiological studies strongly suggest that proanthocyanidins protect against cardiovascular diseases. Despite the antioxidant and anti‐inflammatory properties of these flavonoids, one of the mechanisms by which proanthocyanidins exert their cardiovascular protection is improving lipid homeostasis. Animal studies demonstrate that proanthocyanidins reduce the plasma levels of atherogenic apolipoprotein B‐triglyceride‐rich lipoproteins and LDL‐cholesterol but increase antiatherogenic HDL‐cholesterol. The results in humans, however, are less clear. This review summarizes the results that have been published on plasma triglyceride, apolipoprotein B, HDL‐cholesterol and LDL‐cholesterol levels in humans and animal models in response to proanthocyanidin extracts and proanthocyanidin‐rich foods. The physiological processes and biochemical pathways that are related to lipid homeostasis and affected by proanthocyanidin consumption are also discussed. Intestinal lipid absorption, chylomicron secretion by the intestine and VLDL secretion by the liver are the processes that are most repressed by proanthocyanidins, which, therefore, induce hypolipidemic effects.
Structural determination of two new triterpenoids biotransformed from glycyrrhetinic acid by Mucor polymorphosporus
Authors: Xin Xiu Lan , Yang Guowei , Gou Zhan Ping , Yao Ji Hong , Lan Rong , Ma Xiao Chi 
Published: December 2009

AbstractFive hydroxylated derivatives of glycyrrhetinic acid by Mucor polymorphosporus were isolated. Among them, 6β, 7β‐dihydroxyglycyrrhentic acid (2) and 27‐hydroxyglycyrrhentic acid (3) are new compounds. Their chemical structures were identified by spectral methods including 2D‐NMR. Copyright © 2009 John Wiley & Sons, Ltd.
Modeling of Polymerization Kinetics and Molecular Weight Development in the Microwave‐Activated RAFT Polymerization of Styrene
Authors: Hernández‐Ortiz Julio C. , Jaramillo‐Soto Gabriel , Palacios‐Alquisira Joaquín , Vivaldo‐Lima Eduardo 
Published: December 2009

AbstractA kinetic model for polymerization rate and molecular weight development in the RAFT polymerization of styrene activated by microwave irradiation has been developed. The effect of microwave irradiation was modeled assuming that the monomer can decompose into free radicals, even at temperatures where thermal initiation is negligible. The typical reactions of RAFT polymerization were also included in the model. The model was validated using experimental data from the literature for the RAFT polymerization of styrene with and without AIBN as initiator, and using CPDN as RAFT agent. Overall, good agreement between model predictions and experimental data was obtained.magnified image
An ejection chain algorithm for the quadratic assignment problem
Authors: Rego Cesar , James Tabitha , Glover Fred 
Published: December 2009

AbstractIn this study, we present a new tabu search algorithm for the quadratic assignment problem (QAP) that utilizes an embedded neighborhood construction called an ejection chain. Our ejection chain approach provides a combinatorial leverage effect, where the size of the neighborhood grows multiplicatively while the effort of finding a best move in the neighborhood grows only additively. Our results illustrate that significant improvement in solution quality is obtained in comparison to the traditional swap neighborhood. We also develop two multistart tabu search algorithms utilizing the ejection chain approach in order to demonstrate the power of embedding this neighborhood construction within a more sophisticated heuristic framework. Comparisons to the best large neighborhood approaches from the literature are presented. © 2009 Wiley Periodicals, Inc. NETWORKS, 2010
Mixed search number and linear‐width of interval and split graphs
Authors: Fomin Fedor V. , Heggernes Pinar , Mihai Rodica 
Published: December 2009

AbstractWe show that the mixed search number and the linear‐width of interval graphs and of split graphs can be computed in linear time and in polynomial time, respectively. © 2009 Wiley Periodicals, Inc. NETWORKS, 2010
Polygonal finite elements for topology optimization: A unifying paradigm
Authors: Talischi Cameron , Paulino Glaucio H. , Pereira Anderson , Menezes Ivan F. M. 
Published: December 2009

AbstractIn topology optimization literature, the parameterization of design is commonly carried out on uniform grids consisting of Lagrangian‐type finite elements (e.g. linear quads). These formulations, however, suffer from numerical anomalies such as checkerboard patterns and one‐node connections, which has prompted extensive research on these topics. A problem less often noted is that the constrained geometry of these discretizations can cause bias in the orientation of members, leading to mesh‐dependent sub‐optimal designs. Thus, to address the geometric features of the spatial discretization, we examine the use of unstructured meshes in reducing the influence of mesh geometry on topology optimization solutions. More specifically, we consider polygonal meshes constructed from Voronoi tessellations, which in addition to possessing higher degree of geometric isotropy, allow for greater flexibility in discretizing complex domains without suffering from numerical instabilities. Copyright © 2009 John Wiley & Sons, Ltd.
An edge‐based smoothed finite element method for primal–dual shakedown analysis of structures
Authors: Tran Thanh Ngoc , Liu G. R. , Nguyen‐Xuan H. , Nguyen‐Thoi T. 
Published: December 2009

AbstractAn edge‐based smoothed finite element method (ES‐FEM) using three‐node linear triangular elements was recently proposed to significantly improve the accuracy and convergence rate of the standard finite element formulation for static, free and forced vibration analyses of solids. In this paper, ES‐FEM is further extended for limit and shakedown analyses of structures. A primal–dual algorithm based upon the von Mises yield criterion and a non‐linear optimization procedure is used to compute both the upper and lower bounds of the plastic collapse limit and the shakedown limit. In the ES‐FEM, compatible strains are smoothed over the smoothing domains associated with edges of elements. Using constant smoothing function, only one Gaussian point is required for each smoothing domain ensuring that the total number of variables in the resulting optimization problem is kept to a minimum compared with standard finite element formulation. Three benchmark problems are presented to show the stability and accuracy of solutions obtained by the present method. Copyright © 2009 John Wiley & Sons, Ltd.
Mammalian fauna from Palaeolithic sites in the Upper Yenisei River basin (southern Siberia): Review of the current zooarchaeological evidence
Authors: Kuzmin Yaroslav V. 
Published: December 2009

AbstractThe palaeontological data on mammal remains from two Middle Palaeolithic (ca. 125 000 years ago – 27 200 BP) and 34 (ca. 34 000–12 000 BP) Upper Palaeolithic cultural complexes in the upper part of the Yenisei River basin (southern Siberia) are considered. General features of the faunal assemblages are established. Several issues are discussed, including (a) changes in species composition through time and palaeoenvironmental implications of the zooarchaeological records; (b) patterns of human exploitation (hunting) of mammals; (c) issue of mammoth hunting and (d) possibility of domestication of dog in the late Upper Palaeolithic in the Yenisei River basin. Copyright © 2009 John Wiley & Sons, Ltd.