bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel synthesis of some 1,4‐phenylene‐bis‐heterocyclic carboxamide derivatives
Authors: Abdelrazek Fathy M. , Metwally Nadia H. , Kassab Nazmi A. , Sobhy Nehal A. 
Published: November 2009

Abstract
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N,N′‐(1,4‐phenylene)bis(3‐oxo‐3‐phenylpropanamide) 1 reacts with DMFDMA in refluxing toluene to afford N,N′‐(1,4‐phenylene)bis(2‐benzoyl‐3‐(dimethylamino)acrylamide) 2. Compound 2 reacts with a twofold excess of the active methylene reagents 3a, 3b, 3c to afford the pent‐2‐enediamide derivatives 7 and 8a, 8b, respectively. Compounds 7 and 8a could be cyclized to afford the same compound N,N′‐(1,4‐phenylene)bis(5‐cyano‐6‐oxo‐2‐phenyl‐1,6‐dihydropyridine‐3‐carboxamide) 9a while 8b was cyclized to afford the 6‐thioxo analogue 9b. Compound 2 reacts with hydrazine derivatives 10a, 10b in refluxing ethanol/piperidine to afford the hydrazinylacrylamide derivatives 11a, 11b, which have been cyclized to the corresponding N,N′‐(1,4‐phenylene)bis(1H‐pyrazole‐4‐carboxamide) derivatives 12a, 12b, respectively. Compound 2 reacts also with urea derivatives 13a, 13b, 13c in refluxing ethanol/piperidine to afford the N,N′‐(1,4‐phenylene)bis(2‐benzoyl‐3‐substituted‐acrylamide) derivatives 14a‐c, which could be cyclized into N,N′‐(1,4‐phenylene)bis(6‐phenyl‐1,2‐dihydropyrimidine‐5‐carboxamide)‐2‐oxo; 2‐thioxo or 2‐imino derivatives 15a, 15b, 15c, respectively. J. Heterocyclic Chem., (2009).
Alterations in GluR2 AMPA receptor phosphorylation at serine 880 following group I metabotropic glutamate receptor stimulation in the rat dorsal striatum
Authors: Ahn Sung Min , Choe Eun Sang 
Published: November 2009

AbstractPhosphorylation of ionotropic glutamate receptors in the brain plays a crucial role in the regulation of synaptic plasticity. In this study, we investigated the regulation of α‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propionic acid (AMPA) receptor phosphorylation by thestimulation of group I metabotropic glutamate receptors (mGluRs) in the dorsal striatum in vivo. The results showed that intrastriatal infusion of the group I mGluR agonist, (RS)‐3,5‐dihydroxyphenylglycine (DHPG, 250 nmol), enhanced the sensitivity of GluR2 subunit in its phosphorylation at serine 880 (S880) in the dorsal striatum. This enhancement of the sensitivity of GluR2‐S880 phosphorylation was reduced by blocking group I mGluRs andN‐methyl‐D‐aspartate (NMDA) receptors. Similar reduction of the enhancement was also induced by inhibiting phospholipase C (PLC), calcium/calmodulin‐dependent protein kinase (CaMK), c‐Jun N‐terminal kinase (JNK), and protein kinase C (PKC). Inhibition of protein phosphatase (PP) 1/2A and calcineurin (PP2B) alone enhanced GluR2‐S880 phosphorylation in the dorsal striatum, whereas inhibition of these phosphatases did not further enhance the S880 phosphorylation by DHPG stimulation. In addition, inhibition of PP1/2A or PP2B also enhanced the phosphorylation of CaMKII, JNK and PKC. These data suggest that the phosphorylation of AMPA receptor GluR2 subunit at S880 is subject to the upregulation by the stimulation of group I mGluRs. Interactions among glutamate receptors, protein kinases, and PPs participate in this upregulation. © 2009 Wiley‐Liss, Inc.
Gold‐coated zinc oxide nanowire‐based substrate for surface‐enhanced Raman spectroscopy
Authors: Khan Muhammad A. , Hogan Timothy P. , Shanker B. 
Published: November 2009

AbstractZinc oxide nanowires with two distinct morphologies were synthesized on silicon substrates using a simple thermal evaporation and vapor transport method in an oxidizing environment. The as‐synthesized nanowires were coated with gold to allow excitation of surface plasmons over a broad frequency range. SERS studies with near‐IR excitation at 785 nm showed significant enhancement (average enhancement > 106) with excellent reproducibility to detect monolayer concentrations of 4‐methylbenzenethiol (4‐MBT) and 1,2‐benzendithiol (1,2‐BDT) probe molecules. The Raman enhancement showed a strong dependence on the gold film thickness, and the peak enhancement was observed for a ∼40‐nm‐thick film. The Raman enhancement was stronger for randomly oriented nanowires compared to aligned ones suggesting the importance of contributions from the junctions of nanowires. Copyright © 2009 John Wiley & Sons, Ltd.
Fundamental investigation of interfaces in particle reinforced steel sheets processed by thin strip casting
Authors: Martin M. , Weber S. , Theisen W. , Pyzalla A.R. 
Published: November 2009

AbstractAlong the steel industry history, the production of flat‐steel products has technologically evolved towards reducing slab thickness at the output of the continuous casting machine. This development has been related to the incessant requirement of providing a certain steel quality at lower costs. As a result of this procedure, the thin strip casting technology emerged in a commercial scale at the end of the nineties, with all the advantages of a near‐net‐shape manufacturing process. In particularly, the higher energy efficiency and reduced environmental impact turned it as a very promising and attractive technology for the steel industry.With the purpose of obtaining new types of steel sheets, characterized by improved mechanical and tribological properties, reinforced steel strips have been produced by introducing slight modifications to a twin‐roll caster. In this regard, a considerable enhancement of the mechanical properties has been achieved.
Electron beam welding of titanium aluminides
Authors: Reisgen U. , Holk J. , Olschok S. 
Published: November 2009

AbstractThis paper gives an account of research which has been carried out on electron‐beam welded specimens made of high‐Nb γ/α2‐titanium aluminides (in short: TiAl). The high niobium content of this alloy (5–8 %) has a positive effect on the strength and the creep resistance and also on the oxidation resistance. The standard welding parameters weld speed and beam current and also additional beam oscillation have been used for the determination of factors which will effect the solidification morphology and structural constitution since those, in return, exert influence on the high cracking susceptibility of the alloy. In order to reduce the critical cooling rate, preheating which has a positive effect on crack formation has, in addition, been applied. In a direct comparison of both alloys, micrographs and electron beam micro‐analyses of the developing weld structure and of the HAZ the effects of the beam parameters on both alloys have been established.
Semi‐empirische Berechnungsmethode zur Bestimmung des Grenzformänderungsdiagramms auf Basis mechanischer Kennwerte
Authors: Held C. , Dadrich J. , Denninger R. , Schleich R. , Weidenmann K. A. , Liewald M. 
Published: November 2009

AbstractEin probates Mittel zur Bewertung von Umformprozessen hinsichtlich der werkstofflichen Verarbeitbarkeit ist die Grenzformänderungskurve (Forming Limit Curve, kurz: FLC). Diese kann sowohl experimentell gemessen oder anhand semi‐empirischer mathematischer Modelle berechnet werden. Die bestehenden Modelle sind lediglich für weiche Stahlgüten gültig – Grenzformänderungskurven für hochfeste Stahlgüten bzw. Aluminiumlegierungen können auf diese Weise nicht vorhergesagt werden. Aus diesem Grund beinhaltet dieser Beitrag die Vorstellung einer allgemeingültigen semi‐empirisch basierten Berechnungsmethode für Grenzformänderungskurven, welche für sämtliche im Fahrzeugbau eingesetzten Blechwerkstoffe Gültigkeit besitzt. Diese semi‐empirische Methode basiert auf einer Korrelation zwischen Kennwerten aus dem uniaxialen Zugversuch und experimentell ermittelten Grenzformänderungen. Mit Hilfe dieser Methode ist es möglich, basierend auf den Erkenntnissen aus dem uniaxialen Zugversuch Grenzformänderungsdiagramme für drei Werkstoffklassen (weiche Tiefziehgüten, höher‐ und hochfeste Stahlblechwerkstoffe und Aluminiumlegierungen) vorherzusagen bzw. mit hinreichender Genauigkeit mathematisch zu berechnen.
Apathy may herald cognitive decline and dementia in Parkinson's disease
Authors: Dujardin Kathy , Sockeel Pascal , Delliaux Marie , Destée Alain , Defebvre Luc 
Published: November 2009

AbstractApathy is usually defined as a lack of motivation. It may occur as part of another disorder (notably depression and dementia) or as an isolated syndrome. In Parkinson's disease (PD), apathy is common and several studies have reported an association between this condition and more severe cognitive symptoms, such as executive dysfunction. However, this association has not been thoroughly investigated. The aim of this study (in nondepressed, nondemented PD patients) was to examine whether or not cognitive decline and/or dementia occurred more frequently in apathetic subjects than in nonapathetic subjects. Forty consecutive PD patients participated in the study (20 with apathy and 20 without). None of the subjects were either demented or depressed at the time of study entry. The patients' cognitive functions were extensively assessed twice: at study entry and after an 18‐month follow‐up period. At study entry, the apathetic PD patients had significantly lower global cognitive status and executive function scores than the nonapathetic subjects. After a median period of 18 months, the rate of conversion to dementia was found to be significantly higher in the apathetic group than in the nonapathetic group (8 of 20 and 1 of 20, respectively). Even in nondemented patients, the decrease over time in cognitive performance (mainly executive function but also memory impairment) was significantly greater in apathetic subjects than in nonapathetic subjects. These findings suggest that in nondemented, nondepressed PD patients, apathy may be a predictive factor for dementia and cognitive decline over time. © 2009 Movement Disorder Society
A facility reliability problem: Formulation, properties, and algorithm
Authors: Lim Michael , Daskin Mark S. , Bassamboo Achal , Chopra Sunil 
Published: November 2009

AbstractHaving a robustly designed supply chain network is one of the most effective ways to hedge against network disruptions because contingency plans in the event of a disruption are often significantly limited. In this article, we study the facility reliability problem: how to design a reliable supply chain network in the presence of random facility disruptions with the option of hardening selected facilities. We consider a facility location problem incorporating two types of facilities, one that is unreliable and another that is reliable (which is not subject to disruption, but is more expensive). We formulate this as a mixed integer programming model and develop a Lagrangian Relaxation‐based solution algorithm. We derive structural properties of the problem and show that for some values of the disruption probability, the problem reduces to the classical uncapacitated fixed charge location problem. In addition, we show that the proposed solution algorithm is not only capable of solving large‐scale problems, but is also computationally effective. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2010
Age‐related changes in brain energetics and phospholipid metabolism
Authors: Forester Brent P. , Berlow Yosef A. , Harper David G. , Jensen J. Eric , Lange Nicholas , Froimowitz Michael P. , Ravichandran Caitlin , Iosifescu Dan V. , Lukas Scott E. , Renshaw Perry F. , Cohen Bruce M. 
Published: November 2009

AbstractEvidence suggests that mitochondria undergo functional and morphological changes with age. This study aimed to investigate the relationship of brain energy metabolism to healthy aging by assessing tissue specific differences in metabolites observable by phosphorus (31P) MRS. 31P MRSI at 4 Tesla (T) was performed on 34 volunteers, aged 21–84, screened to exclude serious medical and psychiatric diagnoses. Linear mixed effects models were used to analyze the effects of age on phosphorus metabolite concentrations, intracellular magnesium and pH estimates in brain tissue. A significant age associated decrease in brain pH (−0.53% per decade), increase in PCr (1.1% per decade) and decrease in PME (1.7% per decade) were found in total tissue, with PCr effects localized to the gray matter. An increase in beta NTP as a function of age (1% per decade) approached significance (p = 0.052). There were no effects demonstrated with increasing age for intracellular magnesium, PDE or inorganic phosphate. This study reports the effects of healthy aging on brain chemistry in the gray matter versus white matter using 31P MRS measures of high energy phosphates, pH and membrane metabolism. Increased PCr, increased beta NTP (reflecting ATP) and reduced pH may reflect altered energy production with healthy aging. Unlike some previous studies of aging and brain chemistry, this study examined healthy, non‐demented and psychiatrically stable older adults and specifically analyzed gray‐white matter differences in brain metabolism. Copyright © 2009 John Wiley & Sons, Ltd.
An efficient coarse‐grained parallel algorithm for global–local multiscale computations on massively parallel systems
Authors: Rahul  , De Suvranu 
Published: November 2009

AbstractThe existing global–local multiscale computational methods, using finite element discretization at both the macro‐scale and micro‐scale, are intensive both in terms of computational time and memory requirements and their parallelization using domain decomposition methods incur substantial communication overhead, limiting their application. We are interested in a class of explicit global–local multiscale methods whose architecture significantly reduces this communication overhead on massively parallel machines. However, a naïve task decomposition based on distributing individual macro‐scale integration points to a single group of processors is not optimal and leads to communication overheads and idling of processors. To overcome this problem, we have developed a novel coarse‐grained parallel algorithm in which groups of macro‐scale integration points are distributed to a layer of processors. Each processor in this layer communicates locally with a group of processors that are responsible for the micro‐scale computations. The overlapping groups of processors are shown to achieve optimal concurrency at significantly reduced communication overhead. Several example problems are presented to demonstrate the efficiency of the proposed algorithm. Copyright © 2009 John Wiley & Sons, Ltd.
Novel toughened cyanate ester resin with good dielectric properties and thermal stability by copolymerizing with hyperbranched polysiloxane and epoxy resin
Authors: Zhou Cheng , Gu Aijuan , Liang Guozheng , Yuan Li 
Published: November 2009

AbstractA novel toughened cyanate ester (CE) resin with good dielectric properties and thermal stability was developed by copolymerizing 2,2′‐bis(4‐cyanatophenyl)iso‐propylidene (BCE) with a combined modifier (HBPSiEP) made up of hyperbranched polysiloxane (HBPSi) and epoxy (EP) resin. HBPSi was synthesized through the hydrolysis of 3‐(trimethoxysilyl)propyl methacrylate. The effect of differing stoichiometries of HBPSiEP on the curing characteristics and performance of BCE resin is discussed. Results show that the incorporation of HBPSiEP can not only effectively promote the curing reaction of BCE, but can also significantly improve the toughness of the cured BCE resin. In addition, the toughening effect of HBPSiEP is greater than single EP resin. For example, the impact strength of modified BCE resin with 30 wt% of HBPSiEP is 23.3 KJ/m2, which is more than 2.5 times of that of pure BCE resin, while the maximum impact strength of EP/BCE resin is about 2 times of pure BCE resin. It is worthy to note that HBPSiEP/BCE resins also exhibit improved thermal stability, dielectric properties, and flame retardancy, suggesting that the novel toughened CE resins have great potentiality to be used as a matrix for advanced functional composites or electronic packing resins. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and characterization of pH‐sensitive PAMPS/PVP nanogels in aqueous media
Authors: Atta Ayman M. , El‐Ghazawy Rasha A. M. , Farag Reem K. , Elsaeed Shymaa M. 
Published: November 2009

AbstractA novel method for preparing poly (2‐acrylamido‐2‐methylpropane sulfonic acid) (PAMPS) and poly (vinylpyrrolidone) (PVP) complex nanogels in PVP aqueous solution is discussed in this paper. The PAMPS/PVP complex nanogels were prepared via polymerization of 2‐acrylamido‐2‐methylpropane sulfonic acid (AMPS) monomer in the presence of PVP nanoparticles which formed in water/acetone cosolvent in presence of N, N′‐methylenebisacrylamide (MBA) as a crosslinker, N, N, N′, N′‐tetramethylethylenediamine (TEMED) and potassium peroxydisulfate (KPS) as redox initiator system. The results of FTIR and 1H NMR spectra indicated that the compositions of PAMPS/PVP are consistent with the designed structure. TEM micrographs proved that PAMPS/PVP nanogels possess the spherical morphology before and after swelling. These PAMPS/PVP nanogels exhibited pH‐induced phase transition due to protonation of PAMPS chains. The properties of PAMPS/PVP nanogels indicate that PAMPS/PVP nanogels can be developed into a pH‐controlled drug delivery system. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of aromatic poly(ether amide amide ether ketone ketone)s by electrophilic Friedel–Crafts solution polycondensation
Authors: Cai Mingzhong , Zhu Meihua , Qian Jiangping , Sun Yongfeng 
Published: November 2009

AbstractA new monomer, N,N′‐bis(4‐phenoxybenzoyl)‐p‐phenylenediamine (BPBPPD), was prepared by the condensation of p‐phenylenediamine with 4‐phenoxybenzoyl chloride in N,N‐dimethylacetamide (DMAc). Novel aromatic poly(ether amide amide ether ketone ketone)s (PEAAEKKs) were synthesized by electrophilic Friedel–Crafts solution copolycondensation of BPBPPD with a mixture of terephthaloyl chloride (TPC) and isophthaloyl chloride (IPC), over a wide range of TPC/IPC molar ratios, in the presence of anhydrous aluminum chloride and N‐methylpyrrolidone (NMP) in 1,2‐dichloroethane (DCE). The influences of reaction conditions on the preparation of polymers were examined. The polymers obtained were characterized by different physico–chemical techniques such as FT‐IR, Differential scanning calorimetry (DSC), Thermogravimetric analysis (TGA), and wide angle X‐ray diffraction (WAXD). The polymers with 70–100 mol% IPC are semicrystalline and have remarkably increased Tgs over commercially available poly(ether ether ketone) (PEEK) and poly(ether ketone ketone) (PEKK) due to the incorporation of amide groups in the main chain. The polymers with 70–80 mol% IPC had not only high Tgs of 209–213°C, but also moderate Tms of 339–348°C, which are suitable for melt processing. The polymers with 70–80 mol% IPC had tensile strengths of 107.5–109.8 MPa, Young's moduli of 2.53–2.69 GPa, and elongations at break of 9–11% and exhibited high thermal stability and good resistance to organic solvents. Copyright © 2009 John Wiley & Sons, Ltd.
The maternal age‐specific live birth prevalence of trisomies 13 and 18 compared to trisomy 21 (Down syndrome)
Authors: Savva George M. , Walker Kate , Morris Joan K. 
Published: November 2009

AbstractObjectiveTo estimate the maternal age‐specific live birth prevalence (in the absence of prenatal diagnosis and selective termination) of trisomy 13 (Patau syndrome) and trisomy 18 (Edwards syndrome) and compare it with that of trisomy 21 (Down syndrome).MethodsRecords of prenatal and postnatal diagnoses from seven UK regional congenital anomaly registers and two Australian registers covering 4.5 million births included 975 diagnoses of trisomy 13 and 2254 of trisomy 18. Prevalence at birth in the absence of prenatal diagnosis and selective termination was calculated by adjusting for prenatally diagnosed pregnancies that were terminated according to their likelihood of surviving to term.ResultsThe live birth prevalence in the absence of prenatal screening and selective termination in England and Wales from 1997 to 2004 was 1.4 (95% CI: 1.2–1.6) per 10 000 births for trisomy 13 and 2.3 (95% CI: 2.1–2.5) for trisomy 18. It has increased since 1989–1996, by 13% for trisomy 13 and 25% for trisomy 18. These increases are consistent with those predicted due to increases in maternal age.ConclusionThis study provides the first estimates of maternal age‐specific prevalence of trisomies 13 and 18 for women aged 16–45. Copyright © 2009 John Wiley & Sons, Ltd.
The complete three‐vessel view in prenatal detection of congenital heart defects
Authors: Tongsong Theera , Tongprasert Fuanglada , Srisupundit Kasemsri , Luewan Suchaya 
Published: November 2009

AbstractObjectiveTo evaluate the effectiveness of the complete three‐vessel view (c3VV) in assessment of fetuses with prenatally diagnosed congenital heart defects (CHD).MethodsFetuses with prenatal suspicion of CHD were prospectively recruited into the study. All examinations included a c3VV for assessment of abnormalities in alignment, arrangement, vessel size, number of vessels, aortic arch sidedness and color flow mapping. Definite diagnoses of CHD were based on neonatal cardiologic exams or postnatal autopsy.ResultsOf 106 consecutive fetuses with CHD, 75 were shown to have at least one abnormality on the c3VV, a detection rate of 70.8%. When septal wall defects were excluded, the detection rate increased to 89%. All cases of transposition of great arteries (TGA), aortic stenosis, pulmonary stenosis, truncus arteriosus and ductal aneurysm showed abnormal c3VV. Additionally, abnormal c3VV was also visualized in most cases of double outlet right ventricle (DORV), Ebstein's anomaly and tricuspid atresia. Among the 75 fetuses with congenital heart defects detected at c3VV, some defects had several abnormalities visualized at c3VV. Of interest, two vessels on the c3VV were seen in all five cases of TGA, in all three cases of truncus arteriosus and in one‐third of DORV cases.ConclusionThis prospective descriptive study demonstrates that the c3VV has high detection rate in identifying clues for the presence of CHD, especially when excluding septal wall defects. Thus, c3VV could probably be used as part of routine screening for CHD. Copyright © 2009 John Wiley & Sons, Ltd.
First trimester maternal serum pregnancy‐specific beta‐1‐glycoprotein (SP1) as a marker of adverse pregnancy outcome
Authors: Pihl Kasper , Larsen Torben , Laursen Inga , Krebs Lone , Christiansen Michael 
Published: November 2009

AbstractObjectiveTo establish the first trimester levels of pregnancy‐specific beta‐1‐glycoprotein (SP1) in pregnancies with adverse outcome. Furthermore, to determine the screening performance for adverse outcome using SP1 alone and in combination with other first trimester markers including proMBP and PAPP‐A.MethodsA case‐control study was conducted in a primary hospital setting. The SP1 concentration was measured in first trimester maternal serum in pregnancies with small‐for‐gestational age fetuses (SGA) (n = 150), spontaneous preterm delivery (n = 88), preeclampsia (n = 40) and in controls (n = 500). Concentrations were converted to multiples of the median (MoM) in controls and groups were compared using Mann–Whitney U‐test. Logistic regression analysis was used to determine significant factors for predicting adverse pregnancy outcome. Screening performance was assessed using receiver operating characteristic (ROC) curves.ResultsThe SP1 MoM median was significantly reduced in cases with SGA (0.76 MoM, p < 0.0005) and spontaneous preterm delivery (0.77 MoM, p < 0.0005) whereas no alteration was found in cases with preeclampsia (0.94 MoM, p = 0.723). A significant correlation (r = 0.217) between log10(SP1 MoM) and the birth weight percentile was found in the SGA group. Screening performance was only slightly improved when SP1 was combined with PAPP‐A or proMBP.ConclusionSP1 is a first trimester maternal serum marker of SGA and preterm delivery. Copyright © 2009 John Wiley & Sons, Ltd.