bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of 2‐substituted O,O‐bis(trimethylsilyl) alkylphosphonites with aryl and heterocyclic fragments and their amino or amido derivatives
Authors: Prishchenko Andrey A. , Livantsov Mikhail V. , Novikova Olga P. , Livantsova Ludmila I. , Petrosyan Valery S. 
Published: May 2008

AbstractFree‐radical addition of bis(trimethyl‐siloxy)phosphine to various functionalized alkenes with aryl and heterocyclic fragments is proposed as a convenient procedure for the synthesis of new 2‐substituted alkylphosphonites of corresponding structures. Also the new functionalized derivatives of these phosphonites, including various amino and amido groups as well as certain properties of these compounds, are presented. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:345–351, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20431
Thiol–thione tautomeric forms recognition on the example of 4‐[3‐(2‐methyl‐furan‐3‐yl)‐5‐thioxo‐1,2,4‐triazolin‐4‐yl]acetic acid
Authors: Siwek Agata , Wujec Monika , Wawrzycka‐Gorczyca Irena , Dobosz Maria , Paneth Piotr 
Published: May 2008

AbstractThe synthesis of 4‐[3‐(2‐methyl‐furan‐3‐yl)‐5‐thioxo‐1,2,4‐triazolin‐4‐yl]acetic acid, its structural study in the solid state, and the thiol–thione tautomeric recognition on the basis of spectroscopic data and theoretical calculations are presented. It is shown that NMR spectra, especially 13C and 15N, are indicative of the actual tautomeric form whereas vibrational data can be ambiguous. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:337–344, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20433
Synthesis of tervalent phosphorus esters in biphasic system using potassium phosphate as unique solid base
Authors: Ilia Gheorghe , Iliescu Smaranda , Macarie Lavinia , Popa Adriana 
Published: May 2008

AbstractThe synthesis of tervalent phosphorus esters continues to be a significant area of interest, much of it again directed toward the synthesis of phosphite ligands for metal‐catalyzed reactions. Typically, they were obtained through esterification of the corresponding phosphorus chlorides with the appropriate alcohols in the presence of an amine. In this paper, we present a new method for the synthesis of tervalent phosphorus esters, not yet mentioned in the literature, when potassium phosphate, as a unique base, is used in liquid–solid system. Symmetrical and unsymmetrical phosphites were obtained with good yields (65%–80%) using this method. The compounds were characterized by 31P NMR spectroscopy. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:360–364, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20438
A mild and efficient synthesis of chiral tetrahydroquinolino pyranose derivatives catalyzed by lanthanum(iii) nitrate hexahydrate
Authors: Narasimhulu M. , Reddy S. Malla , Rajesh K. , Suryakiran N. , Ramesh D. , Venkateswarlu Y. 
Published: May 2008

AbstractA mild and highly efficient synthesis of chiral tetrahydroquinolino pyranose derivatives is described. The reaction of a chiral α,β‐unsaturated aldehyde containing a hydroxyl group with different aryl amines using lanthanum(III) nitrate hexahydrate as a catalyst afforded corresponding chiral tetrahydroquinolinated pyranosides in excellent yields. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:429–433, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20441
Halogen switching of azacarbenes C2NH ground states at ab initio and DFT levels
Authors: Kassaee M. Z. , Ghambarian M. , Musavi S. M. 
Published: May 2008

AbstractRelative stabilities and singlet–triplet energy differences are calculated for 24 C2NX azacarbenes (where X is H, F, Cl, and Br). Three skeletal arrangements are employed including azacyclopropenylidene, [(imino)methylene]carbene, and cyanocarbene. Halogens appear to alternate the electronic ground states of C2NH azacarbenes, from triplet to singlet states, at MP3/6‐311++G**, B1LYP/6‐311++G**, B3LYP/6‐311++G**, MP2/6‐311++G**, MP4(SDTQ)/6‐311++G**, QCISD(T)/6‐311++G**, CCSD(T)/6‐311++G**, CCSD(T)/cc‐pVTZ, G1, and G2 levels of theory. The aromatic characters of singlet cyclic azacyclopropenylidenes are measured using GIAO–NICS calculations. Linear correlations are found between the B3LYP/6‐311++G** calculated LUMO–HOMO energy gaps (ΔEHOMO ‐ LUMO) of the singlet carbenes versus their corresponding singlet–triplet energy separations (ΔE). Electrophilic characters are found for all singlet azacarbenes in their addition reactions to alkenes with the highest electrophilicity being exhibited for X = F. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:377–388, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20442
Ylide character and stability of heterocyclic benzenes
Authors: Kassaee M. Z. , Vessally E. , Pirelahi H. , Arshadi S. 
Published: May 2008

AbstractOptimizations are carried out on heterocyclic benzenes including oxabenzene (1O), thiabenzene (1S), selenabenzene (1Se), tellurabenzene (1Te), 1,1‐dihydropyridinium (2N), 1,1‐dihydrophosphinium (2P), 1,1‐dihydroarsinium (2As), and 1,1‐dihydrostybinium (2Sb), using HF and DFT methods with 6‐311++G* basis sets. These partly aromatic compounds have 6π‐electrons showing ylide character. Nonplanar boat conformers appear as global minima for 1X. In contrast, planar conformers are the most stable in 2X series. The inversion barrier energy of heteroatom in 1O appears the least in 1X structures. Ylide character increases in series 1X and 2X with the orders of 1Te > 1O > 1Se > 1S and 2As > 2N > 2Sb > 2P, respectively. Homodesmic studies show stability order for series 1X to be 1S > 1Se > 1Te > 1O, whereas the order of stability for series 2X is 2As > 2P > 2Sb > 2N. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:412–417, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20443
Synthesis of new organophosphorus‐substituted derivatives of functionalized propionates and their analogues
Authors: Prishchenko Andrey A. , Livantsov Mikhail V. , Novikova Olga P. , Livantsova Ludmila I. , Petrosyan Valery S. 
Published: May 2008

AbstractNucleophilic or radical addition of trimethylsilyl esters of trivalent organophosphorus acids to various functionalized acrylates and their cyclic analogues is proposed as convenient methods for the synthesis of new 2‐trimethylsiloxycarbonyl‐substituted alkylphosphonites and their derivatives under mild conditions. Also the new functionalized derivatives of these phosphonites, including amino, amido, and amino acids fragments as well as certain properties of these compounds, are presented as important precursors of new organophosphorus‐substituted derivatives of functionalized propionates and their analogues. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:418–428, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20446
Novel bile acid derived H‐phosphonate conjugates: Synthesis and spectroscopic characterization
Authors: Li Yan , Chu Weijun , Ju Yong 
Published: May 2008

AbstractThe H‐phosphonate bioconjugates of bile acids, conjugated with various alcohols and nucleosides, were obtained in one pot by a tandem transesterification with diphenyl phosphite (DPP). The synthesis of cholic acid derived phosphoramide from the corresponding H‐phosphonate was also demonstrated. The structures of these novel conjugates were confirmed on the basis of IR,31P NMR, 1H NMR, and mass spectra. The synthesized bile acid conjugates were mixtures of diastereoisomers due to the chirality of the phosphorus. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:402–407, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20447
Variations in obstetric practice in Russia: a story of professional autonomy, isolation and limited evidence
Authors: Danishevski Kirill , McKee Martin , Balabanova Dina 
Published: May 2008

AbstractThe Russian health system seeks to ensure consistent models of care through a series of nationwide decrees. Yet patterns of care vary widely, often unrelated to evidence of effectiveness. This study examines care provided by obstetricians in all 19 facilities in a typical Russian region. A first set of structured interviews was conducted with 52 obstetricians, with emerging themes explored in a second set of interviews with 36 of the original interviewees. Accounts were compared with quantitative data on patterns of practice.Obstetricians had little access to information, with only limited use of Russian journals and textbooks and minimal access to international evidence.The decisions made by obstetricians largely determined the overall pattern of care, with midwives, nurses and anaesthetists clearly subordinate. Care was highly medicalized, with many interventions long discarded in the west. There was no obvious reason for widespread variations.Obstetric care in Russia is characterized by widespread use of many harmful or ineffective practices, while many effective ones are not used. Effective policies to tackle these problems will require wide‐ranging policies addressing factors ranging from educational policies to the status of professionals but, above all, will have to confront the legacy of Soviet science that prioritized ideology over evidence. Copyright © 2008 John Wiley & Sons, Ltd.
Mass transfer enhancement by pulsatile flows in grooved channels (the effects of groove length on the resonant mass transfer enhancement)
Authors: Kunitsugu Koji , Nishimura Tatsuo , Tanoue Ken‐Ichiro 
Published: May 2008

AbstractThe effect of groove length on the resonant mass transfer enhancement by pulsatile flow in grooved channel at intermediate Reynolds number was studied for five channels using experimental methods. The mass transport processes from the bottom of the groove to the channel were visualized by an electrolytic precipitation method, and overall and local mass transfer rates were measured by electrochemical methods with a high Schmidt number fluid. The qualitative and quantitative observations show that the range of Strouhal numbers, which gives inertia‐dominated flow, is extended to the low‐value region with groove length. Moreover, it is revealed that a noticeable enhancement is obtained in a specific channel at a Reynolds number for a wide range of Strouhal numbers. The results indicate that there is a specific Reynolds number for transfer enhancement in a channel. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(4): 240–257, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20197
Experimental investigations of a double‐decker jet impingement/film structure's cooling effectiveness
Authors: Liu Zhenxiong , Mao Junkui , Guo Wen , Jiang Hefu 
Published: May 2008

AbstractExperiments were carried out to investigate the cooling coefficient of a laminar double‐decker jet impingement/film structure. Blowing rate M, the ratio of the jet impingement distance to the diameter of the jet hole H/D, the ratio of the distance between the jet hole and film hole to the diameter of the jet hole P/D were changed to study the rules of local cooling coefficient varying with these parameters. All the results show that a higher cooling coefficient was achieved under larger blowing rate conditions. There exists a proper range of H/D and P/D, which can result in a maximum cooling coefficient. It is verified that when H/D=0.5 and P/D=4, the maximum cooling coefficient can be achieved. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(4): 232–239, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20199
Transient flow patterns in a microfluidic chip with a complicated microstructure
Authors: Zhang Wei , Xu Jinliang 
Published: May 2008

AbstractThe transient flow patterns of the boiling flow in a microfluidic chip with a complicated microstructure were studied at low mass fluxes and high heat fluxes. The periodic flow pattern in the timescale of milliseconds and the stratified flow pattern were observed. For a specific separated zone, the liquid film thickness was increased along the flow direction and the dry‐out always occurred earlier at the microchannel upstream rather than downstream. However, for different microchannel zones, the dry‐out took place earlier in the downstream zone. It was determined that the low liquid Froude number was responsible for the formation of the stratified flow. The large boiling number resulted in a large shear stress at the vapor–liquid interface, leading to the accumulation of the liquid in the microchannel downstream, causing the increased liquid film thickness along the flow direction. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(4): 224–231, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20201
Research on the thermal corridor of a hypersonic vehicle
Authors: Jin Ling , Wang An‐Ling , Gui Ye‐Wei , Geng Xiang‐Ren , Tang Wei 
Published: May 2008

AbstractThe establishment of a reasonable physical model and an effective solution scheme for the thermal corridor is very important to thermal protection structure design, trajectory selection, aerodynamic configuration optimization design, etc. The concept of a thermal corridor for a hypersonic vehicle was analyzed and a physical model was proposed in this paper. Furthermore, the governing equations and the corresponding algorithm for the thermal corridor were discussed. The envelopes of the height–velocity curves at typical positions of the vehicle X43 were calculated, the characteristics of the thermal corridor were summarized, the effect of the thermal protection material on the thermal corridor was discussed, and the emission coefficient of the thermal protection material was defined. The results indicate that the thermal corridor depends on the emission coefficient of the surface material, the flow conditions, and turbulence transition position. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(4): 218–223, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20203
Investigation of film cooling and superposition method for double row dustpan‐shaped holes
Authors: Zhu Huiren , Guo Tao , Xu Duchun 
Published: May 2008

AbstractFilm cooling effectiveness for injection from single row and double row dustpan‐shaped holes was studied experimentally. The difference in cooling performance between single row and double row holes are described. The results show that the optimal blowing ratio of injection from double row holes is higher than that of injection from a single row hole. In the case of higher blowing ratios, the traditional superposition calculation method underpredicts the film cooling effectiveness of the double row injection based on that of the single row hole injection. The modified superposition calculation method is given in this paper. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(4): 208–217, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20204
Haptoglobin‐β chain defined by monoclonal antibody RM2 as a novel serum marker for prostate cancer
Authors: Saito Seiichi , Murayama Yasuko , Pan Yuzhuo , Taima Takenobu , Fujimura Tsutomu , Murayama Kimie , Sadilek Martin , Egawa Shin , Ueno Seiji , Ito Akihiro , Ishidoya Shigeto , Nakagawa Haruo , Kato Masanori , Satoh Makoto , Endoh Mareyuki , Arai Yoichi 
Published: May 2008

AbstractIn our previous study, monoclonal antibody RM2, established toward the glycosyl epitope, reflected grade of malignancy of prostate cancer cells whereas RM2 reactivity to benign glands was negative or weak. RM2 reactivity was also detected in stroma, suggesting the glycoprotein RM2 recognizes could be released into the bloodstream. Then, we explored RM2 reactivity to sera of early prostate cancer. We compared RM2 reactivity to sera between 62 patients with early prostate cancer and 43 subjects with benign prostatic disease, and examined RM2 reactivity before and after radical prostatectomy in 15 patients by Western blotting. We also examined RM2 reactivity to sera of the other urogenital cancers. RM2 reactivity was significantly enhanced on a serum glycoprotein with molecular mass ∼40 kDa, hereby termed GPX, in the patients with early prostate cancer when compared with those with benign prostatic disease (p < 0.0001). Setting an appropriate cutoff level, RM2 reactivity to GPX for detection of prostate cancer had sensitivity of 87% and specificity of 84%, respectively. Furthermore, the level of RM2 reactivity significantly decreased after radical prostatectomy (p = 0.006). However, increased RM2 reactivity to GPX was also observed in the other urogenital cancers. The proteomics approach identified GPX as haptoglobin‐β chain and RM2 showed preferential reactivity toward haptoglobin‐β chain derived from prostate cancer when compared with polyclonal anti‐haptoglobin antibody. Haptoglobin‐β chain defined by RM2 is a novel serum marker that may be useful for detection of early prostate cancer when coupled with prostate‐specific antigen because it is not specific to prostate cancer. © 2008 Wiley‐Liss, Inc.
Selective sensitivity to carboxyamidotriazole by human tumor cell lines with DNA mismatch repair deficiency
Authors: Yang Jia‐Lin , Qu Xian‐Jun , Yu Yan , Kohn Elise C. , Friedlander Michael L. 
Published: May 2008

AbstractWe have previously reported that high‐dose nifedipine had a selective antiproliferative effect on colon cancer cell lines deficient in DNA mismatch repair (MMR).We hypothesized that carboxyamidotriazole (CAI), a calcium channel blocker, would also have a selective inhibitory effect on colon cancer cell lines with DNA MMR deficiency. In addition, we speculated that this effect may also be seen in cell lines deficient in DNA MMR derived from other tumor types. Fourteen human cancer cell lines with and without DNA MMR derived from carcinomas of the colon, bladder, ovary and prostate were treated with CAI, vehicle or control drugs (nifedipine and 5‐flurouracil). The effect of treatment on growth inhibition, invasion, apoptosis and cell cycle progression was assessed. Selective sensitivity to CAI was observed in all cancer cell lines deficient in MMR. Compared with the MMR‐proficient cells, the matched deficient cells were significantly more sensitive to the growth inhibitory effect of CAI and nifedipine, but less sensitive to 5‐flurouracil. CAI significantly inhibited the invasive ability of MMR‐deficient cancer cells compared to 5‐flurouracil. CAI induced more apoptosis but similar level of G2/M arrest in MMR (hMLH1− or hMSH6−)‐deficient colon cancer cells than MMR‐proficient counterparts. CAI selectively inhibits proliferation and invasion in MMR‐deficient human cancer cell lines. The antitumor effect is at least partly explained by G2/M cell cycle arrest and induction of apoptosis. These findings may have clinical implications directing clinical trials in selectively targeted patients with DNA MMR tumors. © 2008 Wiley‐Liss, Inc.
Two years after in vivo implantation of poly(DL‐lactide‐ε‐caprolactone) nerve guides: Has the material finally resorbed?
Authors: Meek Marcel F. , Jansen Koen 
Published: May 2008

AbstractLong‐term nerve guide studies on nerve regeneration in vivo are scarce. Previously, we showed that small fragments of biomaterial could still be found on the edge of the epineurium of the regenerated nerve after implantation of poly(DL‐lactide‐ϵ‐caprolactone) [poly(DLLA‐ϵ‐CL), Neurolac®] nerve guides. As these nerve guides are assumed to fully resorb, we studied the 2‐year degradation and possible long‐term foreign body reaction against the nerve guides after implantation in the sciatic nerve of the rat. In addition, the distribution of both collagen type III and IV, and nerve regeneration through the nerve guides were studied and compared with the non‐operated control side. The results demonstrate that nerve regeneration took place through the poly(DLLA‐ϵ‐CL) nerve guides. After 2 years of implantation, biomaterial could not be found macroscopically. Biomaterial fragments in company of multi‐nucleated giant cells and macrophages were found along the regenerated nerve tissue. Collagen III and IV were both found around the epineurium and perineurium in the regenerated nerve, the organization of these layers resembled that of the contra‐lateral non‐operated nerve. Although sufficient nerve regeneration was obtained after long‐term implantation in the rat sciatic nerve, biomaterial fragments and foreign body reactions against these fragments, even after 24 months of implantation, could still be found. The poly(DLLA‐ϵ‐CL), Neurolac nerve guides do resorb, however, not complete up to 2 years of implantation. It is not known whether the remaining biomaterial fragments and foreign body reactions may cause granulomas or other complications after longer implantation periods. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 2009
Structural features of glutamate‐based lipidic materials for small interfering RNA delivery system
Authors: Kusumoto Ken‐ichi 
Published: May 2008

AbstractUnderstanding of materials for small interfering RNA (siRNA) delivery system is essential for the effective design and selection of appropriate materials as potential applications in basic and therapeutic research. However, little attempt has been made to investigate how the structural features of lipidic materials are essential for delivery function. The purpose of this study was to identify the structural features of glutamate‐based lipidic materials as potential siRNA carriers for intracellular delivery. Totally designed lipid didodecylacetylglutamatetrimethylammonium (TMA‐C2‐Glu‐C12) and its analogs were synthesized and estimated by silencing effects of fluorescent protein (EGFP) expression in CHO‐EGFP cells. Here, we demonstrate that TMA‐C2‐Glu‐C12 among a series of lipidic materials is able to perform efficient siRNA delivery with low cytotoxicity into the cells; the transfer ability resulted in 92.2% ± 1.16% of the transferred cells with Cy3‐labeled siRNA. The chemical structure of TMA‐C2‐Glu‐C12 having both hydrophobic chain (CH2CO) in head region, hydrophobic chain ((CH2)11CH3) in tail regions, and ethylene (CH2 CH2) in connector region played a crucial role to enhance the siRNA transfer efficiency. Moreover, compared with commercial reagents, TMA‐C2‐Glu‐C12 was found to have an effective activity for siRNA delivery. These results may improve the novel design and development of lipidic materials on siRNA delivery system. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009