bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Different Sowing Windows on Dry Matter Accumulation of Pigeonpea Genotypes
Authors: Usha N. , Patil S. B. , Nandagavi R. A. 
Published: January 2024

A field experiment was conducted to study the “Effect of different sowing windows on dry matter accumulation of pigeonpea genotypes” at Regional Agricultural Research Station, Vijayapura, during Kharif 2021. The experiment was laid out in a split-plot design assigning four sowing windows to main plots viz., first fortnight of June (23-24th SMW), second fortnight of June (25-26th SMW), first fortnight of July (27-28th SMW) and second fortnight of July (29-30th SMW), whereas genotypes to subplot viz.,TS-3R, GRG-152 and GRG-811 and replicated thrice. The results revealed that sowing in first fortnight of June accumulated more dry matter in leaves (18.47 g plant-1), stem (131.22 g plant-1) and reproductive parts (68.16 g plant-1). Among the genotype GRG-152 accumulated higher dry matter in leaves (17.34 g plant-1) and stem (123.01 g plant-1). However, dry matter accumulation in reproductive parts is higher in TS-3R (63.68 g plant-1). Similarly TDMP was higher in first fortnight of June sowing (217.85 g plant-1) than delayed sowing in second fortnight of July. TS-3R accumulated higher TDMP in the beginning growth stage when compared to GRG-152 and GRG-811. However, TDMP was higher in GRG-152 at later stage. This study revealed that pigeonpea sown in first fortnight of June recorded higher dry matter production and it’s partitioning in leaf, stem and reproductive parts and among the genotype TS-3R recorded significantly higher dry matter in pods due to more photosynthetic activity of the genotype which results in higher yield of the crop.
Maturation of granule cell dendrites after mossy fiber arrival in hippocampal field CA3
Authors: Jones Shawn P. , Rahimi Omid , O'Boyle Michael P. , Diaz Daniel L. , Claiborne Brenda J. 
Published: March 2003

AbstractMost granule neurons in the rat dentate gyrus are born over the course of the first 2 postnatal weeks. The resulting heterogeneity has made it difficult to define the relationship between dendritic and axonal maturation and to delineate a time course for the morphological development of the oldest granule neurons. By depositing crystals of the fluorescent label DiI in hippocampal field CA3, we retrogradely labeled granule neurons in fixed tissue slices from rats aged 2–9 days. The results showed that all labeled granule cells, regardless of the age of the animal, exhibited apical dendrites. On day 2, every labeled neuron had rudimentary apical dendrites, and a few dendrites on each cell displayed immature features such as growth cones, varicosities, and filopodia. Some cells displayed basal dendrites. By day 4, the most mature granule neurons had longer and more numerous apical branches, as well as various immature features. Most had basal dendrites. On days 5 and 6, the immature features and the basal dendrites had begun to regress on the oldest cells, and varying numbers of spines were present. On day 7, the first few adult‐like neurons were seen: immature features and basal dendrites had disappeared, all dendrites reached the top of the molecular layer, and the entire dendritic tree was covered with spines. These data show that dendritic outgrowth occurs before, or concurrent with, axon arrival in the CA3 target region, and that adult‐like granule neurons are present by the end of the first week. Hippocampus 2003;13:413–427. © 2003 Wiley‐Liss, Inc.
Uncoupled analysis of secondary and tertiary protein structure by circular dichroism and electrospray ionization mass spectrometry
Authors: Grandori Rita , Matecko Irena , Müller Norbert 
Published: March 2003

AbstractAn Erratum has been published for this article in Journal of Mass Spectrometry 38 (3) 2003, 345.
Electrospray ionization mass spectrometry (ESI‐MS) applied to protein conformational studies is a powerful new method that seems to provide specific information about protein tertiary structure. In this study, we analyzed the effect of trifluoroethanol (TFE) on a myoglobin peptide and cytochrome c (cyt c) at low pH by circular dichroism (CD) and ESI‐MS. These experiments show that coil‐to‐helix transition per se does not affect ESI mass spectra, confirming that this technique is insensitive to the local conformation of the polypeptidic chain and, rather, reports on the tertiary contacts characterizing different protein conformations. This property makes ESI‐MS an excellent method, complementary to CD, for the characterization of protein conformational changes. Fluorinated alcohols have been suggested to induce molten globule formation in acid‐unfolded cyt c. The experiments described here show that TFE does not induce major changes in the ESI mass spectrum of cyt c at pH 2.2, indicating that no stabilization of compact, globular structures is detectable under the conditions employed. On the other hand, even low concentrations of TFE (2–5%) are shown to destabilize the folded state of the protein around the mid‐point of its acid‐induced unfolding transition. Copyright © 2001 John Wiley & Sons, Ltd.
Liquid chromatographic/mass spectrometric determination of biologically active alkaloids in extracts of Peschiera fuschiaefolia
Authors: Lépine François , Milot S. , Zamir L. , Morel R. 
Published: March 2003

AbstractFour alkaloids were isolated from an alcoholic extract of the bark from the stem of Peschiera fuschiaefolia. Two of these compounds, voacamine and voacamidine, are dimeric alkaloids which are thought to be responsible for the antimalarial activity of these extracts. The mass spectra and the response factors of these four compounds were obtained by liquid chromatography/mass spectrometry in the electrospray positive ionization mode. The concentrations of these alkaloids were measured in two different P. fuschiaefolia extracts. The ion chromatograms of the two extracts were compared on the basis of their [M + H]+ and [M + 2H]+2 ions characteristic of various alkaloids previously isolated from P. fuschiaefolia bark. The two extracts were found to differ mostly in the relative concentrations of the dimeric alkaloids. Copyright © 2002 John Wiley & Sons, Ltd.
SN2 Substitution on sp2 Nitrogen of Protonated Oxime
Authors: Mori Seiji , Uchiyama Katsuya , Hayashi Yujiro , Narasaka Koichi , Nakamura Eiichi 
Published: March 2003

Abstract
Theoretical studies on intramolecular nucleophilic displacement of the protonated oxime oxygen with an aryl ring revealed that the substitution reaction on the sp2 nitrogen atom is a low energy process. This seemingly anomalous substitution is due to the low-lying σ*-orbital of the O-protonated oxime. The theoretical conclusion received experimental support.
Palladium-Catalyzed Coupling Reactions of N-Methoxy-N-methylcarbamoyl Chloride for the Synthesis of N-Methoxy-N-methylamides
Authors: Murakami Masahiro , Hoshino Yujiro , Ito Hajime , Ito Yoshihiko 
Published: March 2003

Abstract
A new synthetic method of N-methoxy-N-methylamides is developed. The palladium-catalyzed coupling reaction of N-methoxy-N-methylcarbamoyl chloride furnished N-methoxy-N-methylamide in moderate to good yield, wherein a carbonyl equivalent was appended to sp and sp2 carbon atoms as a versatile synthetic basis for further manipulation.
Oxorhenium(V) Complex of Amidophenolate: Structure and Redox Characteristics
Authors: Sugimoto Hideki , Sasaki Yoichi 
Published: March 2003

Abstract
A new mono-oxo rhenium(V) complex with a chelating ligand amidophenolate was synthesized and structurally characterized. Significance of the protonation at the amido nitrogen was demonstrated by the large positive shift of the redox potential of Re(IV/III) in the presence of weak proton donors in acetonitrile.
The First Asymmetric Synthesis of Optically Active Tropilidenes. Highly Regio- and Diastereo-differentiating Addition of Diazo Ester to Aromatic Ring Using 2,4-Pentanediol as Chiral Linking Bridge
Authors: Sugimura Takashi , Nagano Shinya , Tai Akira 
Published: March 2003

Abstract
Optically active tropilidenes were prepared by cycloaddition of a diazo ester to an aromatic ring using 2,4-pentanediol as a chiral linking bridge under complete regio- and stereo-differentiations.
Thermal Reaction of Ethyl(hydrido){(2-phosphinoethyl)silyl}iridium(III) Complex—Formation of a {(2-Phosphinoethyl) silyl}(ethene)iridium(I) Complex—
Authors: Okazaki Masaaki , Tobita Hiromi , Ogino Hiroshi 
Published: March 2003

Abstract
Thermolysis of LnIr(C2H5)(H) [Ln={η2-Me2Si(CH2)2PPh2}(PMe3)2] led to the clean formation of a 1 : 1 mixture of ethene complex LnIr(C2H4) and dihydrido complex LnIr(H)2. The former product is proved to be an efficient precursor of an unsaturated silyliridium(I) species through dissociation of ethene.
The Silylformylation of Simple 1-Alkynes Catalyzed by [Rh(cod)][BPh4] in an Ionic Liquid, [Bmim][PF6], under Biphasic Conditions: An Efficiently Reusable Catalyst System
Authors: Okazaki Hiromi , Kawanami Yukio , Yamamoto Keiji 
Published: March 2003

Abstract
Taking into account the precedent rhodium complex-catalyzed silylformylation of 1-alkynes, an efficient recycling of the catalyst consisting of a zwitterionic rhodium complex, [Rh(cod)][BPh4] (cod = 1,5-cyclooctadiene) (2), in a typical ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate [Bmim][PF6] (1), under biphasic conditions was easily achieved.
Low Operating Voltage Bilayer Organic Light Emitting Diodes Using Electrochemically Synthesized and p-Doped Starburst-Polymer as Hole Transport Layer
Authors: Kunugi Yoshihito , Niwa Yoshie , Zhu Lihua , Harima Yutaka , Yamashita Kazuo 
Published: March 2003

Abstract
Bilayer organic light emitting diodes based on electrochemically synthesized and p-doped PTPA hole transport layer have been investigated. When a thin p-doped PTPA layer is inserted between the anode (ITO) and Alq3, the operating voltage of the devices has been clearly decreased while the current density and luminance increased.
A Conjugate Addition of Arylboronic Acids to α,β-Unsaturated Carbonyl Compounds Catalyzed by 2β-CD-[Rh(OH)(cod)]2 or [RhCl(cod)]2 in a Single Aqueous Medium
Authors: Itooka Ryoh , Iguchi Yuki , Miyaura Norio 
Published: March 2003

Abstract
The rhodium-catalyzed conjugate addition of tolylboronic acid to α,β-unsaturated ketones, esters or amides was carried out in water. [RhCl(cod)]2 and 2β-cyclodextrin-[Rh(OH)(cod)]2 complexes were found to catalyze the reaction efficiently in a single aqueous medium.
l-Threoninol as a Chiral Linker of Azobenzene for the Effective Photo-regulation of DNA Triplex Formation
Authors: Takarada Tohru , Tamaru Daisuke , Liang Xingguo , Asanuma Hiroyuki , Komiyama Makoto 
Published: March 2003

Abstract
An azobenzene was enantioselectively attached to the 5′-end of oligo(T) through d- or l-threoninol. Photo-isomerization of azobenzene, tethered on l-threoninol, induced much larger change of melting temperature of triplex formation than did that on the d-form.
Adsorption-Induced Self-Organization of Calix[4]arene on Au(111) Surfaces
Authors: Sakai Takemitu , Ohira Akihiro , Sakata Masayo , Hirayama Chuichi , Kunitake Masashi 
Published: March 2003

Abstract
The construction and sub-molecular visualization of a self-organized adlayer of calix[4]arene on a Au(111) surface were achieved by potential-controlled adsorption and in situ STM. In situ STM images revealed that the self-organized molecular array consisted of a calix[4]arene dimer. The two molecules in a cone conformation with a sideways orientation were connected in a “head to head” orientation between the hydroxy groups.
Crystal Structure Analysis of a Hexatungstate by a High-Energy X-ray Diffraction Experiment Using an Imaging Plate Weissenberg Camera at the BL04B2 Beamline of SPring-8
Authors: Ozeki Tomoji , Kusaka Katsuhiro , Honma Noritaka , Nakamura Yuji , Nakamura Setsuko , Oike Shunsuke , Yasuda Nobuhiro , Imura Hiroyuki , Uekusa Hidehiro , Isshiki Maiko , Katayama Chuji , Ohashi Yuji 
Published: March 2003

Abstract
An imaging plate Weissenberg camera was installed in the BL04B2 beamline of SPring-8 aiming at automated crystal structure determinations of small molecules. Since this beamline is designed to provide X-rays with the energies higher than 37 keV (λ &lt; 0.33 Å), this camera is advantageous in crystal structure analyses of heavily X-ray absorbing materials. The title crystal structure analysis led to precise positional parameters and well-behaved displacement parameters not only for heavy atoms but also for light atoms.
Sodium Perborate Catalyzed Selective Transesterification of β-Keto Esters under Neutral Conditions
Authors: Bandgar B P , Sadavarte V S , Uppalla L S 
Published: March 2003

Abstract
Transesterification of β-keto esters with various alcohols has been carried out using sodium perborate as an inexpensive catalyst under neutral conditions. The effectiveness of the protocol is manifested in its selectivity towards β-keto esters whereas other esters are found to be unreactive under these reaction conditions.
Fe-MCM-41 for Selective Epoxidation of Styrene with Hydrogen Peroxide
Authors: Zhang Qinghong , Wang Ye , Itsuki Satoko , Shishido Tetsuya , Takehira Katsuomi 
Published: March 2003

Abstract
Fe-MCM-41 prepared by direct hydrothermal synthesis catalyzes the epoxidation of styrene with diluted H2O2. The selectivity to styrene oxide reached 67% at styrene conversion of 17% over the catalyst with Si/Fe ratio of 86, which is better than that obtained over TS-1 or a titanium-incorporated silica.
Green High Energy Density Material, N2H2O
Authors: Ding Yi-hong , Inagaki Satoshi 
Published: March 2003

Abstract
We proposed a new concept “green high energy density material” (HEDM) and designed some N2H2O isomers, i.e. oxadiaziridines (1a, 1b), diimide N-oxides (2a, 2b), hydroxydiimides (4a, 4b) and nitrosoamide (5). These isomers satisfy the following conditions: (i) they have high energy densities; (ii) they have considerable kinetic stability; (iii) their green channels are favored more than non-green channels; and (iv) they have high possibility to be actually synthesized for practical use. The very high energy densities of oxadiaziridines (1a, 1b) and the outstanding kinetic stability of diimide N-oxides (2a, 2b) are strongly encouraging the first realization of green HEDM.
Highly Active Delaminated Ti-MWW for Epoxidation of Bulky Cycloalkenes with Hydrogen Peroxide
Authors: Nuntasri Duangamol , Wu Peng , Tatsumi Takashi 
Published: March 2003

Abstract
A novel titanosilicate, prepared by the partial delamination of acid-treated Ti-MWW, possesses an extremely high specific surface area and proves to be a selective and active liquid-phase oxidation catalyst for bulky alkenes.
Novel Sulfoalkoxylated Polyimide Membrane for Polymer Electrolyte Fuel Cells
Authors: Yin Yan , Fang Jianhua , Kita Hidetoshi , Okamoto Ken-ichi 
Published: March 2003

Abstract
A novel sulfoalkoxylated diamine, 2,2′-bis(3-sulfopropoxy)benzidine (2,2′-BSPB) was successfully synthesized and the sulfonated polyimide was prepared from this diamine and 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA). The resulting polyimide membrane displayed high proton conducting performance and excellent water stability, indicating potential application for polymer electrolyte fuel cells.
Diastereoselective Formation of Metallaphosphacyclo Iridium(III) Complexes from Phosphoranido Iridium(III) Complex
Authors: Kajiyama Kazumasa , Nakamoto Atsushi , Miyazawa Shunsuke , Miyamoto Takeshi Ken 
Published: March 2003

Abstract
A phosphoranido iridium(III) complex is prepared by the reaction of Cp*IrCl2(PMe3) with lithium phosphoranide generated from a P–H spirophosphorane bearing two 8-oxy-1-naphthyl groups. The complex is thermally converted into metallaphosphacyclo complexes with diastereoselectivity.
p-Doping of Poly(3-hexylthiophene-2,5-diyl) with Sulfonic Acids and Oxygen Related to Self-doping of Sulfonated Polythiophenes
Authors: Yamamoto Takakazu 
Published: March 2003

Abstract
Poly(3-hexylthiophene-2,5-diyl), P3HexTh, was p-doped by sulfonic acids such as CH3SO3H in the presence of O2. In the case of regioregular head-to-tail type P3HexTh, molecular assembly took place prior to the p-doping. Tetramer and pentamer of thiophene underwent similar oxidation.
Crossed Aldol Reaction Using Polymer-bound Lithium Amides
Authors: Seki Atsushi , Takizawa Youichi , Ishiwata Fusae , Asami Masatoshi 
Published: March 2003

Abstract
Polymer-bound lithium amides were used in an aldol reaction. The introduction of a spacer between the polymer backbone and the reactive site was important to enhance yields of the aldol products. The polymer-bound reagent was repeatedly used in the same reaction after the conversion to the lithium amide.
Phototransamidation as a Method for the Synthesis of N-Glycosyl Asparagines
Authors: Vízvárdi Kristóf , Kreutz Christian , Davis Alexander S , Lee Vincent P , Philmus Benjamin J , Simo Ondrej , Michael Katja 
Published: March 2003

Abstract
N-Glycosyl asparagines were synthesized by a mild photochemical coupling method in which a photoreactive amide of an aspartic acid’s β-carboxyl group is condensed with an aminosaccharide. Upon excitation, the γ-carbon becomes susceptible to nucleophilic attack and the obtained N-glycosyl asparagines, which may be useful building blocks for the synthesis of N-glycopeptides and neoglycopeptides, are generated in good yields.
Synthesis of a Core Trisaccharide as a Versatile Building Block for N‐Glycans and Glycoconjugates
Authors: Unverzagt Carlo 
Published: March 2003

AbstractN‐Linked oligosaccharides from glycoproteins (N‐glycans) can be conveniently assembled with a building block approach. A protected form of the core trisaccharide (β‐mannosyl chitobiose) was identified as a key building block. The chitobiose part of the core trisaccharide was built from a glycosyl fluoride, which served as a precursor for the reducing GlcNAc azide and the inner GlcNAc moiety. β‐Mannosylation was accomplished at the trisaccharide stage by intramolecular inversion of a β‐glucosyl chitobiose. The benzylidene protection of the β‐mannoside and the azido group at the reducing end of the core trisaccharide allow modular synthesis of N‐glycans and their glycoconjugates.
Homogeneous Catalysts Supported on Soluble Polymers: Biphasic Sonogashira Coupling of Aryl Halides and Acetylenes Using MeOPEG‐Bound Phosphine–Palladium Catalysts for Efficient Catalyst Recycling
Authors: Köllhofer Axel , Plenio Herbert 
Published: March 2003

AbstractThe Sonogashira coupling of various aryl bromides and iodides with different acetylenes was studied under biphasic conditions with soluble, polymer‐modified catalysts to allow the efficient recycling of the homogeneous catalyst. For this purpose, several sterically demanding and electron‐rich phosphines of the type RPPR2 were synthesised. They are covalently linked to a monomethyl polyethylene glycol ether with a mass of 2000 Dalton (RP=MeOPEG2000) RPPR2: PR2=CH2C6H4CH2P(1‐Ad)2, C6H4‐P(1‐Ad)2, C6H4‐PPh2. To couple aryl iodides and acetylenes, the catalyst [(MeCN)2PdCl2]/2 RP‐C6H4‐PPh2 was used in CH3CN/Et3N/n‐heptane (5/2/5). The combined yields of coupling product over five reaction cycles are between 80–95 %. There is no apparent leaching of the catalyst into n‐heptane, as evidenced by 1H NMR spectroscopy. The new catalyst [(MeCN)2PdCl2]/2 (1‐Ad)2PBn can be used for room‐temperature coupling of various aryl bromides and acetylenes in THF with HNiPr2 as a base. A closely related catalyst Na2[PdCl4]/2 RP‐CH2C6H4CH2P(1‐Ad)2 linked to the polymer was used to couple aryl bromides and acetylenes in DMSO or DMSO/n‐heptane at 60 °C with 0.5 mol % Na2[PdCl4], 1 mol % RPPR2 and 0.33 mol % CuI. The combined yield of coupling products over five cycles is always greater than 90 %, except for sterically hindered aryl bromides. The determination of the turnover frequency (TOF) of the catalyst indicates only a small decrease in activity over five cycles. Leaching of the catalyst into the product containing n‐heptane solution could not be detected by means of 1H NMR and TXRF; this is indicative of >99.995 % catalyst retention in the DMSO solvent.
The Influence of σ and π Acceptors on Two‐Photon Absorption and Solvatochromism of Dipolar and Quadrupolar Unsaturated Organic Compounds
Authors: Strehmel Bernd , Sarker Ananda M. , Detert Heiner 
Published: March 2003

AbstractTwo‐photon absorption cross sections δ and solvatochromic properties were determined for a series of quadrupolar and dipolar compounds by using femtosecond excitation in the spectral range between 710 and 960 nm. The compounds investigated were distyrylbenzenes and polyenes bearing appropriate π or σ acceptors. The δ values for the centrosymmetric compounds trans,trans‐1,4‐bis[2‐(2′,5′‐dihexyloxy)phenylethenyl]‐2,3,5,6‐tetrafluorobenzene (6), trans,trans‐1,4‐bis[2‐(4′‐dibutylamino)phenylethenyl]‐2,3,5,6‐tetrafluorobenzene (2), trans,trans‐1,4‐bis[2‐(4′dimethylamino)phenylbutadienyl]‐2,3,5,6‐tetrafluorobenzene (7), trans,trans‐1,4‐bis[2‐(4′‐dimethylamino)phenylethenyl]‐2,5‐dicyanobenzene (4) and trans,trans‐1,4‐bis[2‐(4′‐dimethylamino)phenylethenyl]‐2‐propylsulfonyl‐5‐(2‐ethylhexyl)sulfonylbenzene (3) are on the order of 600, 1400, 1700, 3000, and 4100×10−50 cm4 s photon−1, respectively. The corresponding dipolar compounds trans‐2‐(4′‐dimethylaminophenyl)ethenyl‐2,3,4,5,6‐pentafluorobenzene (8), trans‐4‐(4′‐dimethylaminophenyl)butadienyl‐2,3,4,5,6‐pentafluorobenzene (9), trans‐6‐(4′‐dimethylaminophenyl)hexatrienyl‐2,3,4,5,6‐pentafluorobenzene (10) were additionally investigated. All centrosymmtric compounds are good fluorescent materials, while the dipolar chromophores 8–10 exhibit low fluorescence quantum yields. Solvatochromism was also observed for the fluorophores 2–10 as a result of intramolecular charge transfer (ICT). Furthermore, a reasonable correlation was obtained between measured and calculated δ. Quantum chemical calculations were performed by using the INDO Hamiltonian with a MRDCI scheme. The results show that the sum over states (SOS) expression for the second hyperpolarizability γ is appropriate to describe the mechanism of two‐photon absorption. Mechanistic investigations of quadrupolar compounds showed that the energy of the two‐photon excited state is higher than S1.
Photoluminescence Intensity Fluctuations and Electric‐Field‐Induced Photoluminescence Quenching in Individual Nanoclusters of Poly(phenylenevinylene)
Authors: Scheblykin Ivan , Zoriniants George , Hofkens Johan , De Feyter Steven , Van der Auweraer Mark , De Schryver Frans C. 
Published: March 2003

AbstractSubstantial fluctuations of the fluorescence intensity have been detected for single clusters of poly(phenylenevinylene) containing more than 75 polymer chains or 30 000 monomer units. To the best of our knowledge, this is the first time such fluctuations (which resemble the “blinking” effect in single‐molecule fluorescence) have been reported for such a large molecular ensemble containing several macromolecules. Together with the distinct jumps, smooth fluctuations of the fluorescence intensity, with characteristic times from milliseconds to seconds, were observed. This fact distinguishes the fluorescence behaviour of the polymer clusters from that of other multichromophoric systems such as the single chains of conjugated polymers reported in the literature. The consecutive or simultaneous switching of one or several emitting sites from the “on” to “off” state does not explain the character of the fluctuations observed. We suggest that the quenching of the light‐emitting exciton by a long‐lived species, such as, for example, polarons, plays an important role in these unusual fluctuations. Electric field induced fluorescence quenching differs significantly for different clusters. It is proposed that this fluorescence was mainly quenched by polarons injected from the electrodes in the presence of an electric field. The specific behaviour of each cluster is explained by suggesting a different position of the clusters with respect to the electrodes.