bluuebunny/crossref_metadata_2025_split huggingface dataset:
Silica‐gel‐supported Phosphorus Pentoxide:a Simple and Efficient Solid‐supported Reagent for Esterification of Long‐ Chain Carboxylic Acids and Their Antimicrobial Screening
Authors: RAUF Abdul , GANGAL Saloni , SHARMA Shweta 
Published: April 2008

AbstractA silica‐gel‐supported heterogeneous phosphorus pentoxide reagent has been developed for the esterification of various long‐chain carboxylic acids with aromatic alcohols. The reactions occurred under relatively mild conditions and afforded the desired products in good yields. All the compounds 3a–3x were screened for antibacterial and antifungal activity, which showed good activity against Gram positive and Gram negative bacteria and also good results against almost all fungal strains. The structures of the synthesized compounds were elucidated by IR, 1H NMR, 13C NMR, mass spectroscopic techniques and elemental analysis.
An Efficient Ag+ Ionophore Based on Thiacalix[4]arene
Authors: LI Xiong , GONG Shu‐Ling , YANG Wei‐Ping , CHEN Yuan‐Yin 
Published: April 2008

AbstractA novel Ag+ ionophore, p‐tert‐butyl‐tetrakis(hydrazinocarbonylmethoxy)thiacalix[4]arene in 1,3‐alternate conformation (thiacalix[4]arene tetrahydrazide, 1) was synthesized. Its binding properties towards alkali and transition metal cations were studied by noncompetitive liquid‐liquid extraction of alkali metal (Li+, Na+, K+ and Cs+) and transition metal (Co2+, Ni2+, Cu2+, Zn2+, Ag+) picrates. It was found that the thiacalix[4]arene tetrahydrazide exhibited high extractability towards Ag+, lower percent extraction towards Cu2+, and little or no extraction ability towards the others. The selectivity towards Ag+ was further evaluated by competitive Ag+ extraction experiments in the mixture of the above‐mentioned nine cations, the concentration of which was monitored with ICP‐OES. 1H NMR titration experiments and ESI‐MS proved the stoichiometry of 1 to Ag+ was 1:1, and the ′N‐Ag+′ interaction with the assistance of thiacalixarene skeleton was primarily involved in the complexation.
Catalytic Reaction of Aryldiazoacetates with Indole and Its Derivatives:Profound Effect of N‐1 Substitutent on the Reaction Pathways
Authors: ZHANG Xue‐Jing , LIU Sheng‐Ping , YAN Ming 
Published: April 2008

AbstractThe reaction of indole and its derivatives with aryldiazoacetates has been studied in the presence of copper and rhodium catalysts. The electronic property of N‐1 substitutent showed significant effect on the reaction pathways. The electron‐donating group favored the formation of the β‐alkylation products, while the electron‐withdrawing group favored the formation of the cyclopropane products. A reaction mechanism was proposed based on the experimental data and previous research results. The structure of aryl group in diazo compounds also affected the yield of the β‐alkylation products or the cyclopropane products.
Calix[4]arene‐Based Enantioselective Fluorescent Sensors for the Recognition of N‐Acetyl‐aspartate
Authors: QING Guang‐Yan , CHEN Zhi‐Hong , WANG Feng , YANG Xi , MENG Ling‐Zhi , HE Yong‐Bing 
Published: April 2008

AbstractTwo‐armed chiral anion receptors (1 and 2), calix[4]arenes bearing dansyl fluorophore and (1R,2R)‐ or (1S,2S)‐1,2‐diphenylethylenediamine binding sites, were prepared and examined for their chiral amino acid anion binding abilities by the fluorescence spectra in dimethylsulfoxide (DMSO). The results of non‐linear curve fitting indicate that 1 or 2 forms a 1:1 stoichiometry complex with N‐acetyl‐L‐ or D‐aspartate by multiple hydrogen bonding interactions, exhibiting good enantioselective fluorescent recognition for the enantiomers of N‐acetyl‐aspartate, [receptor 1:Kass(D)/Kass(L)=6.74; receptor 2:Kass(L)/Kass(D)=6.48]. The clear fluorescent response difference indicates that receptors 1 and 2 could be used as a fluorescent chemosensor for N‐Acetyl‐aspartate.
Direct Substitution of the Hydroxy Group at the Allylic/propargylic Position with Carbon‐ and Heteroatom‐ centered Nucleophiles Catalyzed by Yb(OTf)3
Authors: HUANG Wen , SHEN Quan‐Sheng , WANG Jia‐Liang , ZHOU Xi‐Geng 
Published: April 2008

AbstractAn efficient and highly selective Yb(OTf)3‐catalyzed direct substitution of the hydroxy group at the allylic and propargylic positions with a variety of heteroatom‐ and carbon‐centered nucleophiles, such as alcohols, thiols, amines, amides and active methylene compounds has been developed. The advantages of the present catalytic system are wide availability of the starting materials, especially for tolerance to thiols, no need for dried solvents and additives, mild conditions, short time of reaction, simple manipulation and environmentally friendly catalyst that can be recovered and reused at least ten times without significant reduction of activity.
Stereoselective Synthesis of trans‐2‐Thien‐α‐oyl‐3‐ [(un)substituted phenyl]‐4‐acetyl‐5‐methyl‐2,3‐dihydrofurans
Authors: JIANG Hai‐Yan , CAO Wei‐Guo , ZHANG Hui , SUN Ru‐Shu , CHEN Jie , DENG Hong‐Mei , SHAO Min , ZHU Shi‐Zheng 
Published: April 2008

AbstractTrans‐2‐thien‐α‐oyl‐3‐[(un)substituted phenyl]‐4‐acetyl‐5‐methyl‐2,3‐dihydrofurans 3 were prepared in good yields with high stereoselectivity by the reaction of thien‐α‐oylmethyltriphenylarsonium bromide 1 with 3‐[(un)substituted benzylidene]‐2,4‐pentadione 2 in benzene in the presence of potassium carbonate at 55 °C. The structure of compound 3 was confirmed by IR, MS, 1H NMR, 1H‐1H COSY, microanalysis and single crystal X‐ray diffraction analysis. The possible reaction mechanism for the formation of products was also proposed.
Photoluminescence and Electroluminescence of Organic Light Emitting Diodes Based on Tris‐(8‐quinolinolato) Aluminum Nanoparticles
Authors: HUA Rui‐Nian , NIU Jing‐Hua , YU Tian‐Zhi , HONG Zi‐Ruo , LI Wen‐Lian , FAN Sheng‐Di 
Published: April 2008

AbstractTris‐(8‐quinolinolato) aluminum (AlQ3) organic nanoparticles with an average diameter 20 nm were prepared through a reprecipitation method. The AlQ3 nanoparticles are spherical and the average particle size does not change by varying the aging time. The photoluminescent and electroluminescent properties were investigated via the AlQ3 nanoparticles and the device based on the AlQ3 nanoparticles, respectively. Blue shift of both the photoluminescence and electroluminescence spectra for the AlQ3 nanoparticles was observed. With increasing the driving bias, the maximum EL emission peak of the AlQ3 nanoparticles was shifted to longer wavelength. The maximum luminance and luminous efficiency of the AlQ3 nanoparticle‐based device are about 600 cd/m2 at driving bias 16V and 0.19 cd/A at a current density of 150 mA/cm2, respectively. The obvious quantum size effect of electro‐luminescence devices with the AlQ3 nanoparticles has been proved, which will open a useful route and new studying field of organic electronic devices, and the study of the fundamental process connecting both of those more conventional classes of materials, i.e., organic molecular crystals.
Synthesis, Crystal Structure, Solid Photochromic Properties and Light‐induced Radical Behavior of Bis{3‐[alkyl/(p‐alkoxyphenyl)]‐3‐hydroxyindan‐1‐on‐2‐ylidene} Derivatives
Authors: HAN Jie , WANG Chang‐Qing , WEI Yong‐Heng , PANG Mei‐Li , MENG Ji‐Ben 
Published: April 2008

AbstractA series of new bis{3‐[alkyl/(p‐alkoxyphenyl)]‐3‐hydroxyindan‐1‐on‐2‐ylidene} derivatives 1–6 were prepared and characterized fully by 1H NMR, IR, MS and elemental analysis data. The structures of compounds 1, 5 and 6 were confirmed by the single‐crystal X‐ray diffraction. The photochromic and light‐induced properties were examined by means of UV‐Vis and electron spin resonance (ESR) spectroscopy methods, respectively. The results show that all the title compounds in this work simultaneously exhibit photochromism in solid state and generate stable free radicals under irradiation with a 200 W high pressure Hg‐lamp. Structure‐property relationship within these photochromic compounds was discussed in the context of their molecular structures and intra‐molecular interactions.
Degradation Action of the Anaerobic Bacteria and Oxygen to the Polymer
Authors: LU Xiang‐Guo , ZHANG Ke 
Published: April 2008

AbstractOxygen could prohibit anaerobic bacterium in the produced water and degrade the polymer molecular chains. Aiming at problems making up aerobic polymer solution by the produced water in Daqing Oil Field, some evaluations were done on the viscosity characteristics of polymer solution and bactericide in anaerobic and aerobic environments. Reasonable aerobic concentration of the produced water was obtained. The experimental results indicate that the viscosity of polymer solution confected by the produced water in the aerobic environment is higher than that of the polymer solution confected by the produced water in the anaerobic environment, and the reasonable aerobic concentration is about 6 mg·L−1. The bactericide has sterilization ability in anaerobic and aerobic environments, but the sterilization effect is better in the aerobic environment.
Nano‐Aluminum Powder Mediated Allylation of Carbonyl Compounds in Aqueous Media
Authors: YUAN Shi‐Zhen , LIU Jin 
Published: April 2008

AbstractA new and effective Barbier‐Grignard allylation of aldehydes or ketones has been carried out with nano‐aluminum powder in aqueous 0.1 mol·L−1 NH4Cl (aq.) under an atmosphere of nitrogen. Aromatic carbonyl compounds gave homoallylic alcohols in good yields. The effectiveness of reaction was strongly influenced by the steric environment surrounding the carbonyl group. Aliphatic carbonyl compounds proceeded in low yields. The dominant stereoisomer was an erythro‐isomer when an ortho‐hydroxyl carbonyl compound was reacted under such a reaction condition.
Synthesis and in vitro Evaluation of α‐GalCer Epimers
Authors: Trappeniers Matthias , Goormans Stijn , Van Beneden Katrien , Decruy Tine , Linclau Bruno , Al‐Shamkhani Aymen , Elliott Tim , Ottensmeier Christian , Werner Joern M. , Elewaut Dirk , Van Calenbergh Serge 
Published: April 2008

Abstractα‐GalCer (also known as KRN7000) is an immunomodulatory glycolipid that is known to potently activate invariant natural killer T (NKT) cells upon CD1d‐mediated stimulation. Because Th1 and Th2 cytokines, which are released after α‐GalCer presentation, antagonize each other's effects, α‐GalCer analogues that induce a biased Th1/Th2 response are highly awaited. In this context, we report the synthesis and in vitro evaluation of α‐Gal‐D‐xylo‐Cer and two α‐Gal‐L‐lyxo‐Cer analogues, one with the natural acyl chain, the other with a truncated chain.
Exploring Acyclic Nucleoside Analogues as Inhibitors of Mycobacterium tuberculosis Thymidylate Kinase
Authors: Familiar Olga , Munier‐Lehmann Hélène , Negri Ana , Gago Federico , Douguet Dominique , Rigouts Leen , Hernández Ana‐Isabel , Camarasa María‐José , Pérez‐Pérez María‐Jesús 
Published: April 2008

AbstractIn the search for novel inhibitors of the enzyme thymidine monophosphate kinase of Mycobacterium tuberculosis (TMPKmt), an attractive target for novel antituberculosis agents, we report herein the discovery of the first acyclic nucleoside analogues that potently and selectively inhibit TMPKmt. The most potent compounds in this series are (Z)‐butenylthymines carrying a naphtholactam or naphthosultam moiety at position 4, which display Ki values of 0.42 and 0.27 μM, respectively. Docking studies followed by molecular dynamics simulations performed to rationalize the interaction of this new family of inhibitors with the target enzyme revealed a key interaction between the distal substituent and Arg 95 in the target enzyme. The fact that these inhibitors are more easily synthesizable than previously identified TMPKmt inhibitors, together with their potency against the target enzyme, makes them attractive lead compounds for further optimization.
Local circuitry in the anterior caudal lobe of the mormyrid cerebellum: A study of intracellular recording and labeling
Authors: Zhang Yueping , Han Phil F. , Han Victor Z. 
Published: April 2008

AbstractThe caudal lobe of the mormyrid cerebellum includes the anterior portion, which is associated with the lateral line and eighth nerve senses, and the posterior portion, which is associated with the electrosense. This study examines the physiology and morphology of cells in the anterior portion in slice preparations. Two subtypes of Purkinje cells, efferent cells and stellate cells, are described. Multipolar Purkinje cells are located in the central region of the lobe, with large, multipolar, spiny dendrites and locally ending axons. Small Purkinje cells are located along its anterior border with the eminentia granularis anterior (EGa), with spiny dendrites in the molecular region. Axons of some small Purkinje cells end locally, whereas axons of other such cells are cut at the surface of the slices, suggesting that they project outside the lobe. Efferent cells are also distributed along the border with EGa. These cells have thin, smooth dendrites in the molecular region, and their axons are cut at the sliced surface. Stellate cells have thin, smooth dendrites and locally terminating axons. Physiologically, all types of cells respond to parallel fiber activation, but only multipolar Purkinje cells showed characteristic all‐or‐none climbing fiber responses. Although the majority of Purkinje cells fire a single type of spikes at resting level, a subset of small Purkinje cells fire small, narrow and large, broad spikes. Thus, the anterior caudal lobe of the mormyrid cerebellum is different from the mammalian cerebellum in having different subtypes of Purkinje cells and local termination of many Purkinje cell axons. J. Comp. Neurol. 509:1–22, 2008. © 2008 Wiley‐Liss, Inc.
Distribution and neurochemical identification of pancreatic afferents in the mouse
Authors: Fasanella Kenneth E. , Christianson Julie A. , Chanthaphavong R. Savanh , Davis Brian M. 
Published: April 2008

AbstractDysfunction of primary afferents innervating the pancreas has been shown to contribute to the development of painful symptoms during acute and chronic pancreatitis. To investigate the distribution and neurochemical phenotype of pancreatic afferents, Alexa Fluor‐conjugated cholera toxin B (CTB) was injected into the pancreatic head (CTB‐488) and tail (CTB‐555) of adult male mice to label neurons retrogradely in both the dorsal root ganglia (DRG) and nodose ganglia (NG). The NG and DRG (T5–T13) were processed for fluorescent immunohistochemistry and visualized by using confocal microscopy. Spinal pancreatic afferents were observed from T5 to T13, with the greatest contribution coming from T9–T12. The pancreatic afferents were equally distributed between right and left spinal ganglia; however, the innervation from the left NG was significantly greater than from the right. For both spinal and vagal afferents there was significantly greater innervation of the pancreatic head relative to the tail. The total number of retrogradely labeled afferents in the nodose was very similar to the total number of DRG afferents. The neurochemical phenotype of DRG neurons was dominated by transient receptor potential vanilloid 1 (TRPV1)‐positive neurons (75%), GDNF family receptor alpha‐3 (GFRα3)‐positive neurons (67%), and calcitonin gene‐related peptide (CGRP)‐positive neurons(65%) neurons. In the NG, TRPV1‐, GFRα3‐, and CGRP‐positive neurons constituted only 35%, 1%, and 15% of labeled afferents, respectively. The disparity in peptide and receptor expression between pancreatic afferents in the NG and DRG suggests that even though they contribute a similar number of primary afferents to the pancreas, these two populations may differ in regard to their nociceptive properties and growth factor dependency. J. Comp. Neurol. 509:42–52, 2008. © 2008 Wiley‐Liss, Inc.
Novel interleaved ZVS converter with ripple current cancellation
Authors: Lin B.‐R. , Huang C.‐L. , Li M.‐Y. 
Published: April 2008

AbstractThis paper presents a zero voltage switching (ZVS) converter with interleaved pulse‐width modulation scheme. An active clamp circuit is adopted in the proposed converter to recycle the energy stored in the leakage inductor of the transformer and reduce the voltage stress of the main power switch in the converter. The ZVS feature of switches can be achieved due to the resonance during the transition interval of two power switches. Two full‐wave rectifiers with ripple current cancellation are connected in parallel at the output side to reduce the current stress of the secondary winding of transformers. Instead of the conventional interleaved forward converter, power switches in the proposed converter can perform the functions of both forward converter and active clamp at the same time. Therefore, the circuit components in the power circuit are less than that of in the conventional interleaved forward converter. The operation principle and system analysis of the proposed converter are provided. Some experimental results for a 240 W (12 V/20 A) prototype are provided to demonstrate the effectiveness of the proposed converter. Copyright © 2008 John Wiley & Sons, Ltd.
Accurate differential tanh(nx) implementation
Authors: Carrasco‐Robles Manuel , Serrano Luis 
Published: April 2008

AbstractThis paper presents a novel non‐linear neural activation function architecture that approximates the tanh(nx) function accurately. The purpose of this realization is the description of a circuit that can be designed to obtain different slopes at the origin of the activation function. The special features of transistors working in the subthreshold region are combined with current mode techniques in order to minimize power consumption and occupied area. Moreover, the circuit has been designed with fully differential and balanced topologies so that the external influences, offset, and distortion of even order are reduced. The proposed activation function is thoroughly explained and it is analysed taking the body effect into account. Some modifications are applied in order to immunize it from the body effect, and simulated results for an implementation on a 0.35 µm AMI technology are presented. Copyright © 2008 John Wiley & Sons, Ltd.
MOS‐integrable circuitry for multi‐scroll chaotic grid realization: A SPICE‐assisted proof
Authors: Gandhi Gaurav , Roska Tamas 
Published: April 2008

AbstractA MOS‐integrable circuit realization of the class ofMulti‐Scroll Gridattractor using an implementation of nonlinear transconductor is presented. The design can be seen as the MOS‐integrable circuit implementation of modified jerk equations presented in the literature (Int. J. Bifurcat. Chaos2002;12(1):23–41). The proposed design ofMulti‐Scroll Gridattractor is adequately supported by SPICE simulation results. Copyright © 2008 John Wiley & Sons, Ltd.
A strategy for efficient handling of fresh tumor needle biopsies that allows histological and cytopathological assessment
Authors: Cohen Marta C. , Marven Sean , Walker Jenny , Gerrard Mary 
Published: April 2008

AbstractNeo‐adjuvant chemotherapy prior to surgery is used in the management of many pediatric solid tumors, and diagnosis is therefore valuable and is frequently made by percutaneous needle biopsy.We describe a method that enhances tissue preservation and obtains a sample for rapid cytopathological assessment.Biopsies are placed in Ham's F10 culture's medium in theatre and transferred to pathology. The biopsies are retrieved from the medium and dealt as before (submit to cytogenetics; fix in glutharaldheyde; snap frozen at −80°C and routine histology). An equal amount of 90% alcohol is then added to the Ham culture's medium fluid received from theatre before performing a cytospin preparation and a cell clot.We used this method in the diagnosis of 16 tumors demonstrating that this allows a more efficient handling of the biopsy, makes possible a same day diagnosis, enhances the quality of the immunohistochemistry and maximizes the amount of tissue available for diagnosis. Diagn. Cytopathol. 2008;36:285–289. © 2008 Wiley‐Liss, Inc.
Adult granulosa cell tumor of the ovary: Fine‐needle‐aspiration cytology of 10 cases and review of literature
Authors: Ali Sarfraz , Gattuso Paolo , Howard Allison , Mosunjac Marina B. , Siddiqui Momin T. 
Published: April 2008

AbstractAdult granulosa cell tumor (GCT) of the ovary is mostly diagnosed in postmenopausal women. They typically secrete estrogen, which stimulates the endometrium to proliferate and cause abnormal bleeding. This study reviews the cytologic features of adult GCT of the ovary diagnosed by fine‐needle aspiration (FNA). We reviewed slides from ten cases diagnosed by CT guided FNA from 1995 to 2007 at our institutions. Smears were stained with Diff‐Quik and Papanicolaou stains. Patient's history and histologic diagnosis were also available and reviewed for all cases. The patients ranged in age from 39 to 83 yr. All 10 cases were hypercellular with both large and small overlapping cell clusters and individual cells. The cytologic features identified included: naked nuclei (10/10 cases), Call‐Exner bodies (7/10 cases), blood vessels with prominent perivascular tumor cell growth (4/10 cases), spindle‐shaped hyperchromatic stromal cells within cellular clusters (6/10 cases), mixed inflammation (3/10 cases), tumor cell necrosis (1/10 cases), and prominent metachromatic stroma seen in association with blood vessels (1/10 cases). Moderate to scant delicate cytoplasm was also seen (10/10 cases). Small, punctuate cytoplasmic vacuoles were also noted (7/10 cases) and were occasionally prominent (3/10 cases). In general nuclear to cytoplasmic ratios were high although lower than those typically seen in a lymphoma or small‐cell carcinoma. Nuclei were generally centrally located although eccentrically located nuclei were consistently seen in a minority of cells. Nuclei were monotonous in size showing slightly convoluted (occasional rentiform and fetiform nuclei) to polygonal outlines. Prominent, central nucleoli were also seen (4/10 cases). Nuclear grooves were also seen (9/10 cases). No atypical mitotic activity was identified in any of the 10 cases (0/10 cases). In summary, the above cytologic features can also help in the cytologic diagnosis of adult GCTs. Diagn. Cytopathol. 2008;36:297–302. © 2008 Wiley‐Liss, Inc.
Fine‐needle aspiration of fibrous dysplasia of bone: A worthwhile endeavor or not?
Authors: Huening Michael A. , Reddy Suraj , Dodd Leslie G. 
Published: April 2008

AbstractFine‐needle aspiration (FNA) is a minimally invasive technique which is enjoying ever‐increasing popularity in the initial diagnosis of many pathologic processes. However, FNA diagnosis of neoplasms occurring within bones is less commonly employed and is not the preferred method in some types of bony lesions. Fibrous dysplasia is a primary neoplasm of bone for which it is not yet clear whether FNA can reliably yield adequate diagnostic material.Review of data from 82 cases of fibrous dysplasia diagnosed between 1990 and 2006 yielded six cases, in which diagnosis was initially attempted by FNA prior to open biopsy and surgical resection. Corresponding cytologic, histologic, and imaging characteristics of the cases were reviewed.Of the six cases in which initial diagnosis was attempted by FNA, only two of six (33%) yielded adequate diagnostic material. Smears of aspirated material in all cases contained nonspecific elements, including fragments of benign host bone and cartilage, bland stromal cells, adipocytes, blood, and debris. Importantly, the two positive FNA cases were dependent on the concurrent core needle biopsy (all smears of aspirate material were nondiagnostic).Even with image guidance, FNA is insufficient to obtain diagnostic material for cases of suspected fibrous dysplasia of bone. Core needle biopsy at least is recommended to obtain adequate material, and to reduce the risk of misdiagnosis due to sampling error. Diagn. Cytopathol. 2008;36:325–330. © 2008 Wiley‐Liss, Inc.