bluuebunny/crossref_metadata_2025 huggingface dataset:
17-Allylamino-17-demethoxygeldanamycin (17-AAG) is effective in down-regulating mutated, constitutively activated KIT protein in human mast cells
Authors: Fumo Gerard , Akin Cem , Metcalfe Dean D. , Neckers Len
Published: October 2003

Mutations in the proto-oncogene c-kit cause constitutive kinase activity of its product, KIT protein, and are associated with human mastocytosis and gastrointestinal stromal tumors (GISTs). Although currently available tyrosine kinase inhibitors are effective in the treatment of GISTs, there has been limited success in the treatment of mastocytosis. 17-Allylamino-17-demethoxygeldanamycin (17-AAG), a benzoquinoid ansamycin antibiotic, which binds to heat shock protein 90 (hsp90) causes destabilization of various hsp90-dependent kinases important in oncogenesis. Treatment with 17-AAG of the mast cell line HMC-1.2, harboring the Asp816Val and Val560Gly KIT mutations, and the cell line HMC-1.1, harboring a single Val560Gly mutation, causes both the level and activity of KIT and downstream signaling molecules AKT and STAT3 to be down-regulated following drug exposure. These data were validated using Cos-7 cells transfected with wild-type and mutated KIT. 17-AAG promotes cell death of both HMC mast cell lines. In addition, neoplastic mast cells isolated from patients with mastocytosis, incubated with 17-AAG ex vivo, are selectively sensitive to the drug compared to the mononuclear fraction. These data provide compelling evidence that 17-AAG may be effective in the treatment of c-kit-related diseases including mastocytosis, GISTs, mast cell leukemia, subtypes of acute myelogenous leukemia, and testicular cancer. (Blood. 2004;103:1078-1084)
lockjawencodes a zebrafishtfap2arequired for early neural crest development
Authors: Knight Robert D. , Nair Sreelaja , Nelson Sarah S. , Afshar Ali , Javidan Yashar , Geisler Robert , Rauch Gerd-Joerg , Schilling Thomas F.
Published: October 2003

The neural crest is a uniquely vertebrate cell type that gives rise to much of the craniofacial skeleton, pigment cells and peripheral nervous system, yet its specification and diversification during embryogenesis are poorly understood. Zebrafish homozygous for the lockjaw (low)mutation show defects in all of these derivatives and we show that low (allelic with montblanc) encodes a zebrafish tfap2a, one of a small family of transcription factors implicated in epidermal and neural crest development. A point mutation in lowtruncates the DNA binding and dimerization domains of tfap2a, causing a loss of function. Consistent with this, injection of antisense morpholino oligonucleotides directed against splice sites in tfap2a into wild-type embryos produces a phenotype identical to low. Analysis of early ectodermal markers revealed that neural crest specification and migration are disrupted in low mutant embryos. TUNEL labeling of dying cells in mutants revealed a transient period of apoptosis in crest cells prior to and during their migration. In the cranial neural crest, gene expression in the mandibular arch is unaffected in low mutants, in contrast to the hyoid arch, which shows severe reductions in dlx2 and hoxa2 expression. Mosaic analysis, using cell transplantation,demonstrated that neural crest defects in low are cell autonomous and secondarily cause disruptions in surrounding mesoderm. These studies demonstrate that low is required for early steps in neural crest development and suggest that tfap2a is essential for the survival of a subset of neural crest derivatives.
Thresholded scalogram and its applications in process fault detection
Authors: Jeong Myong K. , Chen Di , Lu Jye‐Chyi
Published: October 2003

Scalograms provide measures of signal energy at various frequency bands and are commonly used in decision making in many fields including signal and image processing, astronomy and metrology. This article extends the scalogram's ability for handling noisy and possibly massive data. The proposed thresholded scalogram is built on the fast wavelet transform, which can capture non‐stationary changes in data patterns effectively and efficiently. The asymptotic distribution of the thresholded scalogram is derived. This leads to large sample confidence intervals that are useful in detecting process faults statistically, based on scalogram signatures. Application of the scalogram‐based data mining procedure (mainly, classification and regression trees) demonstrates the potential of the proposed methods for analysing complicated signals for making engineering decisions. Copyright © 2003 John Wiley & Sons, Ltd.
Applications of Hilbert–Huang transform to non‐stationary financial time series analysis
Authors: Huang Norden E. , Wu Man‐Li , Qu Wendong , Long Steven R. , Shen Samuel S. P.
Published: October 2003

A new method, the Hilbert–Huang Transform (HHT), developed initially for natural and engineering sciences has now been applied to financial data. The HHT method is specially developed for analysing non‐linear and non‐stationary data. The method consists of two parts: (1) the empirical mode decomposition (EMD), and (2) the Hilbert spectral analysis. The key part of the method is the first step, the EMD, with which any complicated data set can be decomposed into a finite and often small number of intrinsic mode functions (IMF). An IMF is defined here as any function having the same number of zero‐crossing and extrema, and also having symmetric envelopes defined by the local maxima, and minima respectively. The IMF also thus admits well‐behaved Hilbert transforms. This decomposition method is adaptive, and, therefore, highly efficient. Since the decomposition is based on the local characteristic time scale of the data, it is applicable to non‐linear and non‐stationary processes. With the Hilbert transform, the IMF yield instantaneous frequencies as functions of time that give sharp identifications of imbedded structures. The final presentation of the results is an energy–frequency–time distribution, which we designate as the Hilbert Spectrum. Comparisons with Wavelet and Fourier analyses show the new method offers much better temporal and frequency resolutions. The EMD is also useful as a filter to extract variability of different scales. In the present application, HHT has been used to examine the changeability of the market, as a measure of volatility of the market. Published in 2003 by John Wiley & Sons, Ltd.
Interphalangeal sesamoid bones of the great toe: An anatomic variant demanding careful scrutiny of radiographs
Authors: Davies M.B. , Abdlslam K. , Gibson R.J.
Published: October 2003

We describe a patient who was found to have two sesamoid bones at the interphalangeal joint of the right great toe after radiographs for dislocation of the joint. Recognition of the sesamoids required careful scrutiny of the films. Interphalangeal sesamoids may cause painful callosities plantar to the joint or may become incarcerated in a dislocated joint. Our patient made a good recovery. The presence of sesamoid bones on the medial and lateral sides of the joint was unusual. Clin. Anat. 16:520–521, 2003. © 2003 Wiley‐Liss, Inc.
In the Twilight Zone between [2]Pseudorotaxanes and [2]Rotaxanes
Authors: Jeppesen Jan O. , Vignon Scott A. , Stoddart J. Fraser
Published: October 2003

A [2]pseudorotaxane, based on a semi‐dumbbell‐shaped component containing asymmetrically substituted monopyrrolotetrathiafulvalene and 1,5‐dioxynaphthalene recognition sites for encirclement by cyclobis(paraquat‐p‐phenylene) and with a “speed bump” in the form of a thiomethyl group situated between the two recognition sites, has been self‐assembled. This supramolecular entity is a mixture in solution of two slowly interconverting [2]pseudorotaxanes, one of which is on the verge of being a [2]rotaxane at room temperature, allowing it to be isolated by employing flash column chromatography. These two [2]pseudorotaxanes were both characterized in solution by UV/Vis and 1H NMR spectroscopies (1D and 2D) and also by differential pulse voltammetry. The spectroscopic and electrochemical data reveal that one of the complexes behaves wholly as a [2]pseudorotaxane, while the other has some [2]rotaxane character to it. The kinetics of the shuttling of cyclobis(paraquat‐p‐phenylene) between the monopyrrolotetrathiafulvalene and the 1,5‐dioxynaphthalene recognition sites have been investigated at different temperatures. The shuttling processes, which are accompanied by detectable color changes, can be monitored using UV/Vis and 1H NMR spectroscopies; the spectroscopic data have been employed in the determination of the rate constants, free energies of activation, enthalpies of activation, and the entropies of activation for the translation of cyclobis(paraquat‐p‐phenylene) between the two recognition sites.
Historische Pigmente unter Laserbestrahlung: Restaurierung von Kulturgütern
Authors: Chappé Marie , Hildenhagen Jens , Dickmann Klaus , Bredol Michael
Published: October 2003

Die Verwendung von Laserstrahlung zur Reinigung kunsthistorischer Objekte etabliert sich in den letzten Jahren zunehmend. Ein besonders verbreitetes und schwieriges Problem sind dabei Farbfassungen. Sie reagieren sehr empfindlich auf Laserstrahlung. In dieser Studie wurde untersucht, mit welchen Parametern (Wellenlänge, Energiedichte) und in welchem Ausmaß reine Pigmente unter Laserbestrahlung verändert werden. Es wurde gezeigt, dass die Farbveränderungen unterschiedliche Gründe haben kann: Sie können z.B. durch laserinduzierte Oxidation, Reduktion oder Phasenumwandlung verursacht werden.
Heiße Quellen am Meeresboden: Erzfabriken in der Tiefsee
Authors: Herzig Peter
Published: October 2003

Mit der Entdeckung der ersten Metallsulfidablagerungen und 350 °C heißen Black Smoker im Bereich des Ostpazifischen Rückens im Jahre 1979, begann die wissenschaftliche Untersuchung dieser einzigartigen Mineralvorkommen der Tiefsee. Heute sind in den Weltozeanen mehr als 200 Hydrothermalvorkommen bekannt, wovon zirka 30 momentan aktiv sind. Die im Umfeld der heißen Quellen entstehenden Mineralablagerungen sind die rezenten Gegenstücke einer bedeutenden Gruppe von Erzvorkommen (Massive Sulfidlagerstätten), die sich heute an Land befinden, aber ehemals am Grunde von Urozeanen gebildet wurden. Dieser Zusammenhang macht die Black Smoker‐Vorkommen der Tiefsee zu natürlichen Labors der Erzlagerstättenforschung. Zudem haben die zum Teil hohen Bunt‐ und Edelmetallgehalte der Meeresbodenvorkommen bereits zu Überlegungen geführt, diese Vererzungen eines Tages wirtschaftlich und umweltverträglich zu gewinnen. Erste Schritte hierzu sind bereits unternommen worden.
Mephitis mephitis, Du stinkst so sehr!
Authors: Roth Klaus
Published: October 2003

Wer der übelste Stinker in der Natur ist, darüber sind sich Laien und Fachleute einig: es ist Mephitis mephitis, das gestreifte Stinktier [1]. Es wundert daher nicht, dass nur wenige Wissenschaftler verwegen genug waren, sich an das Stinktier heranzuwagen. Aus ihren Arbeiten wissen wir, dass das Sekret ein hochkomplexer Naturstoff und ein Meisterstück der Schwefelchemie ist.
Polycarbonate
Authors: Hübner Karl
Published: October 2003

Heute werden weltweit jährlich fast zwei Millionen Tonnen einer Kunststoffklasse verarbeitet, die in diesen Tagen ihren 50. Geburtstag feiert: Am 17. Oktober 1953 reichten die Farbenfabriken Bayer AG ihren Patentantrag über ein „Verfahren zur Herstellung thermoplastischer Kunststoffe”︁ beim Deutschen Patentamt ein. Es ging um Polycarbonate.
Achieving proportional DiffServ per‐hop behaviour with PLQF
Authors: Li Jung‐Shian , Lai Hsing‐Chien , Lin Yi‐Ting
Published: October 2003

We propose a novel scheme that can provide both delay and loss proportional DiffServ per‐hop behaviour. DiffServ is a framework that can provide different QoS levels to different groups of network users, and eliminate the shortcoming of the best‐effort delivery in today's Internet. The scheme employs probabilistic longest queue first (PLQF) as its forwarding and dropping mechanism. PLQF mainly reacts immediately to the queue‐length fluctuation of each service class, and then decides the probability for each QoS class, which determines the forwarding or dropping behaviour. We couple delay and loss differentiated services in one scheme. The proposed scheme is proven to achieve proportional differentiated services after detailed evaluations. Furthermore, the implementation cost of PLQF is much less than that of the previously proposed schemes, such as WTP and PLR. Copyright © 2003 John Wiley & Sons, Ltd.
Ethical issues in psychotherapy with adolescents
Authors: Koocher Gerald P.
Published: October 2003

Treating adolescents in psychotherapy presents a number of unique ethical challenges. Because many adolescents who enter treatment have not yet attained the age of majority, reside in families that include other people with emotional difficulties, attend school, become involved with community agencies (e.g., the courts), and must generally take direction from adult authority figures, the role of the therapist becomes particularly complex. The unique dilemmas include developing specialized clinical competence, treatment contracting, choice of treatment modality, direction of the therapeutic process, and confidentiality. This article discusses the range of ethical concerns involved in treating adolescents and suggests strategies for optimal ethical care. © 2003 Wiley Periodicals, Inc. J Clin Psychol/In Session.
Rab3D redistribution and function in rat parotid acini
Authors: Ngyen Danielle , Jones Antoinette , Ojakian George K. , Raffaniello Robert D.
Published: October 2003

An Erratum has been published for this article in Journal of Cellular Physiology 199: 316, 2004.

Rab3D is a low molecular weight GTP‐binding protein believed to be involved with regulated secretion in many cell types. In parotid, Rab3D is localized to secretory granule membranes or present in the cytosol as a complex with Rab escort protein. In the present study, we examined the redistribution of membrane‐associated Rab3D during secretion in permeabilized parotid acini. When permeabilized acini were stimulated with calcium and cAMP, amylase release increased greater than twofold over basal. Quantitative immunoblotting of subcellular fractions revealed that Rab3D did not dissociate from parotid membranes during secretion. Immunohistochemical staining demonstrated that Rab3D co‐localizes with amylase containing granules that are found in the apical pole of the cell. Upon stimulation with calcium and cAMP, Rab3D and amylase immunostaining of granules appeared to be more dispersed. However, Rab3D immunostaining was not observed on the plasma membrane and appeared to reside in the apical cytoplasm. To examine the role of Rab3D in amylase release, cytosolic extracts containing myc‐tagged Rab3D and Rab3DQ81L, a GTP‐binding mutant, were prepared and incubated with streptolysin O‐permeabilized acini. Rab3D, but not Rab3DQ81L, bound to parotid membranes suggesting that Rab3D‐binding to parotid membranes is guanine nucleotide‐dependent. Moreover, wild‐type and mutant Rab3D inhibited agonist‐induced amylase release from permeabilized parotid acini. These observations indicate that in parotid acini, Rab3D does not dissociate from parotid membranes or redistribute to the plasma membrane during secretion, and may play an inhibitory role in regulated secretion. The fact that both wild‐type Rab3D and the GTP‐binding mutant inhibit amylase release suggests that binding of Rab3D to the membrane is not essential for secretory inhibition.
J. Cell. Physiol. 197: 400–408, 2003© 2003 Wiley‐Liss, Inc.
Mineralization of dissolved organic carbon in mineral soil solution of two forest soils
Authors: Schwesig David , Kalbitz Karsten , Matzner Egbert
Published: October 2003

Dissolved organic carbon (DOC) constitutes an important carbon input flux to forested mineral soils. Seepage from mineral subsoils contains only small amounts of DOC because of mineralization, sorption or the formation of particulate organic matter (POM). However, the relation between these processes is largely unknown. Therefore, the objective of this study was to quantify the mineralization of DOC from different depths of forest soils, and to determine degradation rate constants for rapidly and slowly degradable DOC pools. Mineralization of DOC and formation of POM in mineral soil solution from two forested sites in northern Bavaria (Germany) were quantified in a 97 days laboratory incubation experiment. Furthermore, spectroscopic properties such as specific UV absorption and a humification index derived from fluorescence emission spectrometry were measured before and after incubation. DOC in all samples turned out to belong mainly to the stable DOC pool (> 95 %) with half‐lives ranging from years to decades. Spectroscopic properties were not suitable to predict the mineralization of DOC from mineral soils. However, together with data on DOC from the forest floor and long‐term data on DOC concentrations in the field they helped to identify the processes involved in C sequestration in mineral subsoils. Mineralization, formation of POM, and probably sorption seem all to be responsible for maintaining low concentrations of DOC in the upper mineral soil. DOC below the upper mineral soil is highly resistant to mineralization, and thus the further decrease of DOC concentrations in the subsoil as observed under field conditions cannot be attributed to mineralization. Our results suggest that sorption and to some minor extent the formation of POM may be responsible for C sequestration in the subsoil.
Vertical distribution and bioavailability of 137Cs in organic and mineral soils
Authors: Kruse‐Irmer Sven , Giani Luise
Published: October 2003

The vertical distribution and bioavailability of 137Cs in Histosols and mineral soils with different physicochemical properties from the southeast of Bavaria (Germany) more than ten years after the Chernobyl accident were the focus of this study.

The vertical distribution of 137Cs was low in the investigated soils. About 85–98 % of the total 137Cs was located in the upper 10 cm of the mineral soils. Slightly higher 137Cs percentages were observed in deeper soil layers of the peat soils. Although the organic matter is assumed to enhance 137Cs mobility in soils, 137Cs was also located in the upper 10 cm of the peat soils (73–85 %). The highest 137Cs‐activities were found in the humus layers of forest soils, where 45–93 % of the total 137Cs soil inventories were observed. To determine the bioavailability of radiocesium, the soil‐to‐plant transfer of 137Cs and additionally added 134Cs was investigated under controlled conditions. The results revealed that the 134+137Cs soil‐to‐plant transfer factors as well as the percentages of NH4‐exchangeable 134+137Cs were much higher for the peat soils and humus layers than for the mineral soils. Nevertheless, the migration of 137Cs from the humus layers to the underlying soils was low. Considering the high bioavailability and low migration of radiocesium in the humus layers, it is suggested that radiocesium is involved in a shortcut element cycle in the system humus layer‐plant uptake‐litter. Furthermore, the organic matter has to be taken into account for radiocesium immobilization.
α‐Fe layer formation during metal dusting of iron in CO‐H2‐H2O gas mixtures
Authors: Zhang J. , Schneider A. , Inden G.
Published: October 2003

The formation of an α‐Fe layer between cementite and graphite was observed and investigated during metal dusting of iron in CO‐H2‐H2O gas mixtures at both 600°C and 700°C. The condition to form this phenomenon is determined by the gas composition which depends on temperature. The iron layer formation was observed for CO content less than 1 % at 600°C and less than 5 % at 700°C. With increasing CO contents, no α‐Fe layer was detected at the cementite/graphite interface by optical microscopy. In this case cementite directly contacts with the coke layer. The morphologies of the coke formed in the gas mixtures with low CO contents were also analysed. Three morphologies of graphite have been identified with 1 % CO at 600°C: filamentous carbon, bulk dense graphite with columnar structure, and graphite particle clusters with many fine iron containing particles embedded inside. At 700°C with 5 % CO the coke mainly consists of graphite particle clusters with some filamentous carbon at the early stage of reaction. Coke analysis by X‐ray diffraction shows that both α‐Fe and Fe3C are present in the coke. The mechanism of α‐Fe accumulation between cementite and graphite is discussed in this paper.
Aliphatic‐Aromatic Hyperbranched Polyesters by Polycondensation of Potassium 3,5‐Bis(bromomethyl)benzoate: Formation of Cyclic Structures
Authors: Sepulchre Maurice , Sepulchre Marie‐Odile , Belleney Joël
Published: October 2003

Aliphatic‐aromatic hyperbranched polyesters of reasonable degrees of branching (DB's) but of relatively low molar masses were prepared from 3,5‐bis(bromomethyl)benzoic acid (2a). 2a was synthesized by radical bromination of 3,5‐dimethylbenzoic acid. The polymerization of 2a and that of the potassium salt of 2a (2K), both carried out in the presence of a potassium monocarboxylate (RCOOK), led to directly derivatized polyesters. Polyesters bearing free CH2Br groups were obtained by polymerization of 2K alone or in the presence of 2,4,6‐tris(bromomethyl)mesitylene (TBMM) or by polymerization of 2a in the presence of RCOOK provided that 1 ≤ [RCOOK]/[2a] < 2. These polyesters were later derivatized by reaction with RCOOK. In all cases, RCOOK can be chosen in order to introduce, in the polyesters, reactive functional groups such as unsaturated (double or triple bond) and hydroxy ones. The NMR analysis of polymers has shown that a cyclic dimer (C2) was formed in most cases. Its amount depends on the process of polymerization and on the experimental conditions. The $\overline M _{\rm n}$ of polyesters was found to be correlated with the amount of C2. The MALDI‐TOF analysis of polymers confirmed the formation of cycles and showed that both the polymerization of 2K in the presence of TBMM and that of 2a in the presence of some particular RCOOK's led to the formation of acyclic macromolecules.

Expanded aromatic region of the 1H NMR spectrum of a polymer showing the six characteristic resonances H, H, H, H, H and H of the cyclic dimer C2.

magnified image

Expanded aromatic region of the 1H NMR spectrum of a polymer showing the six characteristic resonances H, H, H, H, H and H of the cyclic dimer C2.
Thermoreversible Supramolecular Organization in Poly(vinylidene fluoride)–Dodecyl Benzene Sulfonic Acid Blends
Authors: Habibur Rahman M. , Malik Sudip , Nandi Arun K.
Published: October 2003

Blends of poly(vinylidene fluoride) (PVF2) and dodecyl benzene sulfonic acid (DBSA) were found to phase separate in the melt state from hot‐stage polarizing optical microscopy and differential scanning calorimetry (DSC). Both these studies also indicated the formation of a reversible mesomorphic order in the DBSA‐rich phase of the blends. Scanning electron microscopy (SEM) showed a fibrillar network morphology of the DBSA‐rich phase. Wide‐angle X‐ray diffraction (WAXD) revealed the formation of a lamellar structure in the blends corresponding to a long period of 26 Å. The mesomorphic nature of the blends is believed to arise from the supramolecular organization of the surfactant molecules within the lamella. Thermal study indicated that the supramolecularly organized complex is the VF2 monomer unit:DBSA ≈ 4:1, and the enthalpy of complexation is ∼723 J · mol−1.

SEM micrograph of a PVF2‐DBSA blend with weight fraction of DBSA (WDBSA) = 0.62.

magnified image

SEM micrograph of a PVF2‐DBSA blend with weight fraction of DBSA (WDBSA) = 0.62.
Adducts of Polymeric Organolithiums with 1,1‐Diphenylethylene. Rates of Formation and Crossover to Styrene and Diene Monomers
Authors: Quirk Roderic P. , Lee Bumjae
Published: October 2003

The addition reactions of 1,1‐diphenylethylene (DPE) to polymeric organolithium (PLi) compounds and the crossover reactions of the resulting polymeric 1,1‐diphenylalkyllithiums with styrene, isoprene and butadiene monomers have been investigated and optimized. The addition of poly(styryl)lithium (PSLi) to one unit of DPE at 25 °C is complete in 6 and 8 h in benzene and cyclohexane, respectively. After 3 d at 25 °C, the extent of end‐capping with DPE was only 9% for poly(butadienyl)lithium and 15% for poly(isoprenyl)lithium. Addition of THF ([THF]/[PLi] = 15–40) promotes quantitative addition of poly(dienyl)lithiums to DPE within 1–4 hours at 25 °C. Crossover reactions of polymeric 1,1‐diphenylalkyllithiums (growth out) to styrene monomers are slow relative to crossover reactions to diene monomers. Crossover to diene monomers is complete within approximately 2 min at 25 °C and leads to well‐defined, narrow molecular weight distribution block copolymers ($\overline M _{\rm w} /\overline M _{\rm n}$ = 1.01 with $\overline M _{\rm n}$ (out, calc) > 2 900 g · mol−1). Crossover to styrene monomers requires 12 h and leads to broad molecular weight distributions ($\overline M _{\rm w} /\overline M _{\rm n}$ > 1.1) and inefficient crossover if $\overline M _{\rm n}$ (out; calc) < 7 000 g · mol−1 and the chain end concentration is ≤ 10−3 M. Crossover to the styrene monomer is favored by low temperatures (5 °C), high chain end concentrations, and higher molecular weights of the growing block.

magnified image
Comparative study by simulation of photovoltaic pumping systems with stationary and polar tracking arrays
Authors: Illanes R. , De Francisco A. , Torres J. L. , De Blas M. , Appelbaum J.
Published: October 2003

Using mathematical models for the different components of the photovoltaic pumping system: generator, inverter (if applicable), motors, pumps and piping, we have developed a computer program that, for given irradiance and temperature data, calculates the flow of water pumped at any given time. The program has been applied to study the hourly and yearly water flow pumped by a photovoltaic pumping system located in Madrid, employing centrifugal pumps powered by AC motors. The photovoltaic generator consists of, in one case, a stationary array and in the second case a polar tracking array. The hourly radiation data were estimated from the distribution of the atmospheric clearness coefficients and the monthly average daily radiation on a horizontal surface. The results of this study show that the use of a polar tracking array increases the average yearly water flow compared with the stationary array more than the corresponding increase of the incident radiation on the arrays. Copyright © 2003 John Wiley & Sons, Ltd.
Experimental analysis of battery charge regulation in photovoltaic systems
Authors: Díaz Pablo , Ángel Egido Miguel
Published: October 2003

The influence of charge regulation on batteries for stand‐alone photovoltaic systems is analysed in relation to two factors: battery lifetime and the daily energy service supplied. The regulation thresholds adjusted in the charge controller (for disconnection and reconnection), in overcharge and deep discharge conditions, determine the whole system operation. Laboratory testing procedures are proposed and applied to different components of the photovoltaic rural electrification market. Finally, technical recommendations for charge regulation of lead–acid batteries are presented. Copyright © 2003 John Wiley & Sons, Ltd.
Morphology‐dependent luminescence properties of poly(benzyl ether) dendrimers
Authors: Kimata Shu‐Ichi , Jiang Dong‐Lin , Aida Takuzo
Published: October 2003

Poly(benzyl ether) dendrimers with o‐, m‐, and p‐isomers of dialkoxybenzene at their focal points [o‐, m‐, and p‐(Gn)2Ar], having generation numbers (n) of 0–3, were synthesized. 1H NMR pulse relaxation times (T1) of the exterior MeO groups of o‐ and m‐(Gn)2Ar (n = 0–3) all remained in the range of 0.92–1.43 s. In sharp contrast, an exceptionally short T1 value (0.23 s) was observed for p‐(G3)2Ar. Although their absorption spectral profiles were slightly different from one another, an essential difference was observed for their fluorescence properties. When the generation number was increased, the fluorescence efficiency of o‐(Gn)2Ar increased, but that of p‐(Gn)2Ar decreased, whereas m‐(Gn)2Ar exhibited a relatively small change in the fluorescence efficiency. Fluorescence depolarization studies showed a highly efficient intramolecular energy migration in p‐(G3)2Ar as compared with o‐(G3)2Ar and m‐(G3)2Ar. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3524–3530, 2003
Solvent‐free polycondensation of 1,3‐bis(hydroxyphenylmethyl)benzene. II. The dramatic difference in the polymerization behavior between meso and racemic isomers
Authors: Suzuki Masato , Sasaki Takeshi , Matsuura Go , Kimura Mika
Published: October 2003

The meso and racemic forms of 1,3‐bis(hydroxyphenylmethyl)benzene underwent solvent‐free polycondensation with the aid of an acid catalyst giving polyether. Very interestingly, the diastereoisomerism caused a considerable difference in the polymerization behavior. The meso isomer (mp = 96–98 °C) was polymerized even at 65 °C, whereas the racemic one (mp = 158–160 °C) required heating at 100 °C to undergo polymerization. However, the latter produced a much higher molecular weight than the former (30,000 vs 4000). The contamination of the meso isomer with the racemic one very sensitively reduced the polymerization temperature: the 98.5% meso monomer underwent polymerization at 50 °C. In contrast to solvent‐free polymerization, two diastereomeric monomers showed almost identical behavior in solution polymerization. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3564–3571, 2003
Alternating copolymerization of carbon dioxide and epoxide by manganese porphyrin: The first example of polycarbonate synthesis from 1‐atm carbon dioxide
Authors: Sugimoto Hiroshi , Ohshima Hiromitsu , Inoue Shohei
Published: October 2003

The first successful example of the formation of polycarbonate from 1‐atm carbon dioxide and epoxide was demonstrated by the alternating copolymerization of carbon dioxide and epoxide with manganese porphyrin as a catalyst. The copolymerization of carbon dioxide and cyclohexene oxide with (porphinato)manganese acetate proceeded under the 1‐atm pressure of carbon dioxide to give a copolymer with an alternating sequence. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3549–3555, 2003
Synthesis of glycosaminoglycans via enzymatic polymerization
Authors: Kobayashi Shiro , Itoh Ryosuke , Morii Hidekazu , Fujikawa Shun‐Ichi , Kimura Shunsaku , Ohmae Masashi
Published: October 2003

Hyaluronic acid and chondroitin were successfully synthesized as representative molecules of glucosaminoglycans and galactosaminoglycans found in a glycosaminoglycan family via enzymatic polymerization catalyzed by testicular hyaluronidases. A newly designed N‐acetylhyalobiuronate oxazoline derivative with a β‐D‐glucuronyl‐(1→3)‐N‐acetyl‐D‐glucosamine disaccharide structure served as a transition‐state analogue substrate monomer for the enzyme, giving rise to artificial hyaluronic acid in 52% yields with a number‐average molecular weight of 1.35 × 104 through ring‐opening polyaddition in a perfect regioselective and stereoselective manner. A novel N‐acetylchondrosine oxazoline derivative with a β‐D‐glucuronyl‐(1→3)‐N‐acetyl‐D‐galactosamine disaccharide structure also acted as a transition‐state analogue substrate monomer for the enzyme, yielding artificial chondroitin in 35% yields with a number‐average molecular weight of 2.5 × 103. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3541–3548, 2003
Cofacially constrained organic semiconductors
Authors: Tovar John D. , Swager Timothy M.
Published: October 2003

We present the synthesis, spectroscopy, and electrochemistry of bis[oligo(thiophene)] monomers where the sterics of covalently attached subunits enforced oblique spatial orientations. The synthetic scheme applied to a variety of chromophores; standard bromination and cross‐coupling chemistry afforded bis(terthienyl)benzene systems in high yield. We prepared model systems consisting of mono(terthiophene)s to probe the effects that van der Waals contacts impose during electropolymerization and methyl‐blocked analogues to examine the electrochemical properties of derivatives that do not undergo polymerization. We discuss the extent of delocalization between chromophores as deduced from electrochemical studies and demonstrate that these materials provide viable electrochromic polymers. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3693–3702, 2003
Quasi‐biennial variation of the 5‐day wave in the stratosphere
Authors: Miyoshi Y. , Hirooka T.
Published: October 2003

Interannual variability of the 5‐day wave in the stratosphere is examined by the use of National Center for Environmental Prediction reanalysis data. Quasi‐biennial variation of the 5‐day wave amplitude is clearly seen in the stratosphere. This quasi‐biennial variation is closely related to the zonal wind variation associated with the equatorial quasi‐biennial oscillation in the stratosphere. We give a short description of the mechanism bringing about the relationship.
A model of sea‐foam thickness distribution for passive microwave remote sensing applications
Authors: Reul N. , Chapron B.
Published: October 2003

Foam formations at the sea surface significantly contribute to microwave brightness temperature signatures over the ocean for moderate to high wind speeds. The thickness of foam layers generated by breaking waves follows a specific distribution due to unsteadiness of breaking and the large range of wave scales involved in the phenomenon. Although the effect of a distributed thickness‐parameter on the foam‐induced microwave brightness temperature may be comparable to or larger than the fractional whitecap coverage, it is not yet included in brightness models. To fill this gap, we develop a dynamical model for the conditional fraction of sea‐surface covered by whitecaps with given thickness, as a function of wind speed. It is an integrated function of the foam‐layer lifetime and of the distribution of the total length of breaking fronts at given scale. The depth at which air bubbles are injected into the water column is scaled with breaking front velocity using reported dynamical properties of unsteady breaking regions. For wind speed less than 20 m/s, the model predicts that two thirds of the fractional whitecap coverage is due to layers on average thinner than 60 cm and 35 cm for crest‐ and static‐foam formations, respectively. In unstable atmospheric conditions, an increase in wind speed from 7 to 20 m/s corresponds to a coverage‐weighted foam‐layer thickening of about 1 cm and 3.5 cm, respectively. In neutral conditions, the thickening is approximately 2 times lower. Still, this will induce doubling of foam emissivity at Ku and C bands.
The Space Weather Journal: How It Began
Authors: Robinson Robert
Published: October 2003

The idea for a journal dedicated to space weather grew out of an AGU Chapman Conference in 2000. A major obstacle to improving operational space weather forecasting arises because much high‐quality research is not effectively transitioned for operational use. A large part of the problem resides in the lack of interaction among the communities involved in space weather activities. The primary goal of Space Weather: The International Journal of Research and Applications is to promote communication among scientists, engineers, technicians, science administrators, and space weather policy makers in a way that leads to continuous improvement in the nation's ability to mitigate space environment hazards to technical systems on the ground and in space.
Stereological study on the submandibular gland in hypothyroid ratsNote
Authors: Noorafshan Ali
Published: October 2003

Most research done on hypothyroidism has focused on physiological and biochemical aspects of the tissues, whilst there has been little work on tissue morphology especially on salivary glands. The present study has used hypothyroid Wistar rats as a model for investigating the effects of hypothyroidism on submandibular gland structure. Two groups of Wistar rats were studied. One was made hypothyroid with methimazole and the second was an untreated euthyroid group (control). They were euthanised after 10 weeks. Submandibular glands were removed and studied. Systematic random transverse sections were obtained from submandibular glands and subjected to morphometric analysis. Volume density and absolute volume of granular, striated and excretory ducts and interlobular connective tissue were estimated by point counting. Volume‐weighted mean particle volume of serous and mucous acini was also determined by unbiased stereology. Absolute volume of granular ducts in the submandibular gland of hypothyroid rats was reduced by ∼50% (p<0.009) whilst that of the striated and excretory ducts and interlobular connective tissue was unaffected. Volume of serous acini was also significantly (p<0.03) lower in hypothyroid rats. These changes suggest that hypothyroidism has an effect on submandibular gland structure, and that this effect occurs mostly in two major exocrine compartments (granular duct and serous acinus) of the gland.
Can ungulates foraging in a multiple‐use landscape alter forest nitrogen budgets?
Authors: Seagle Steven W
Published: October 2003

Ungulates alter nutrient dynamics within many of Earth's ecosystems. However, whether foraging ungulates transfer nutrients among ecosystems at a magnitude sufficient to alter nutrient budgets and associated ecological processes is unknown. I suggest that within eastern North American landscapes dominated by agriculture and forest, the juxtaposition of high nitrogen crops for foraging and forest used for diurnal concealment promotes a net transfer of nitrogen from cropland to forests by overabundant white‐tailed deer (Odocoileus virginianus). To estimate the magnitude of this nutrient transfer I apply allometric relationships of deer nitrogen consumption and excretion to populations within a hypothetical landscape in which deer use forest and cropland in equal proportions daily and are not limited in habitat use by landscape spatial pattern. Results indicate a non‐linear relationship between deer nitrogen deposition to forest and percent forest cover, with deposition rising toward estimated atmospheric nitrogen deposition when forest covers less than 40% of the landscape. This “spatial subsidy” of nitrogen to the forest‐floor represents a previously unrecognized input to the forest nitrogen budget with equally unknown impacts on forest‐floor ecosystem processes.
The interaction between epiphytic algae, a parasitic fungus and Sphagnum as affected by N and P
Authors: Limpens Juul , Raymakers Jeffrey T. A. G. , Baar Jacqueline , Berendse Frank , Zijlstra Jantineke D.
Published: October 2003

We report the effects of fertilisation with N and P on the infection of Sphagnum by its fungal parasite Lyophyllum palustre, the expansion of epiphytic algae and the interaction between the latter two from 1998 to 2001. We added 40 kg N ha−1 yr−1 or 3 kg P ha−1 yr−1 in a full factorial design at 4 field sites. In a greenhouse experiment we reinoculated Sphagnum to verify the identity of the fungus and its necrotic effect on Sphagnum.

Lyophyllum palustre was responsible for the necrosis of Sphagnum in our experiments. Adding N induced complete necrosis of Sphagnum cuspidatum by L. palustre, whereas adding P decreased the area of necrotic tissue. Disease severity was related to the N concentration in the Sphagnum capitula. In Sphagnum magellanicum and S. papillosum, infection with L. palustre resulted in defoliation of stem sections. Adding N stimulated the expansion of algae at all sites, reducing the volume of photosynthetic tissue in Sphagnum. The density of the film of algae in the treatments receiving N was a function of the frequency of defoliated Sphagnum stems.

We conclude that infection with parasitic fungi and, in humid environments, the expansion of epiphytic algae, may aggravate the impact of increased N deposition or of other ecosystem disturbances that affect nutrient availability.
Perfusion of melatonin into the prefrontal cortex disrupts the circadian rhythm of acetylcholine but not of locomotor activity
Authors: de Prado Blanca Marquez , Reiter Russel J. , Mora Francisco
Published: October 2003

Abstract: Extracellular concentrations of acetylcholine (ACh) in the prefrontal cortex displayed a circadian rhythm, with a maximum increase in the dark phase of the light:dark cycle. The increase in ACh related well to the circadian rhythm of the same rats in which a maximal increase of locomotor activity in the dark phase also was observed. Local perfusion of melatonin (200–500 μm), in a dose‐dependent manner, disrupted the ACh rhythm in the prefrontal cortex but did not affect the circadian rhythm of locomotor activity. It is suggested that the change in the cholinergic transmission during a circadian period in the prefrontal cortex may be under the control of the biological clock through the action of melatonin; however, the prefrontal cortical ACh cycle seems not to be related to the regulation of locomotor activity.
Immunoprotection of Gonads and Genital Tracts in Human Embryos and Fetuses: Immunohistochemical Study
Authors: GUREVICH PAVEL , BEN‐HUR HERZL , BERMAN VALENTINA , MOLDAVSKY MOISEY , SZVALB SERGIO , ZUSMAN ITSHAK
Published: October 2003

PROBLEM: The immune protection of genital organs in embryogenesis has not been sufficiently studied. The purpose of this study was to investigate the development of the secretory immune system (SIS) in the gonads and genital tracts of human embryos and fetuses.  MATERIALS AND METHODS: Developing gonads at different stages and genital tracts from 18 embryos and 39 fetuses in the first to third trimester of gestation were analyzed for presence of different component of SIS: secretory component (SC), joining (J) chain, IgA, IgM, IgG, macrophages, and subsets of lymphocytes. The material was divided into two groups: cases not subjected to foreign antigenic effects (group I, n=31) and those under antigenic attack (chorioamnionitis, group II, n=26).  RESULTS: In embryos and fetuses of group I, SC, J chain, and IgG were seen in the epithelium of mesonephric and paramesonephric ducts, proliferating coelomic epithelium, epithelium of the uterine tubes and uterus, epithelium of the vas deferens, epididymis, and rete testis. IgA and IgM appeared in 6‐week‐old embryos. J chain, IgA, IgM, and IgG, but not SC, were found in the primary oocytes and oogonia, spermatogonia, and interstitial cells. An abundance of macrophages was seen in 4‐week‐old embryos. T and B lymphocytes first appeared in 6–7‐week‐old embryos. In embryos and fetuses of group II, reactivity of immunoglobulins (Igs) decreased until they disappeared altogether.  CONCLUSIONS: Components of SIS were seen in genital organs in 4–5‐week‐old embryos and were present during the whole intrauterine period. We suggest the presence of two forms of immune protection of fetal genital organs. One form contains SC, J chain, and Igs and is present in the genital tract epithelium. The second form contains only J chain and Igs and is present in germ cells of gonads. The loss of Igs in cases with chorioamnionitis reflects the functional participation of the SIS of genital organs in response to antigen attack.
Role of the Actin Cytoskeleton in Regulating Endothelial Permeability in Venules
Authors: VALESKI J. EDWARD , BALDWIN ANN L.
Published: October 2003

Objective: This study was performed to determine the effect of myosin light chain kinase (MLCK) inhibition on histamine‐ and thrombin‐induced venular permeability in the rat mesentery, coincidental with actin cytoskeleton changes.

Methods: The mesenteric microvasculature of rats was perfused with a fluorescent tracer plus thrombin, histamine, or buffered saline, and the preparation was suffused with the MLCK inhibitor ML‐7. The microvasculature then was stained for actin.

Results: The average (±SE) number of leaks per micrometer of venule length of the thrombin plus 5 µM ML‐7 treatment (35.3 ± 5.9 × 10−4; n = 224) was significantly lower than that for the thrombin‐only treatment (61.7 ± 5.6 × 10−4; n = 385; p < 0.001). The histamine preparations required higher concentrations of ML‐7 to significantly reduce the number of leaks. A concentration of 100 µM reduced the average leak number from 20.8 ± 3.9 × 10 4 (n = 140) to 2.5 ± 0.8 × 10−4 (n = 383; p < 0.001), but 20 µM ML‐7 had no effect. Although leaky areas of both the thrombin‐ and histamine‐treated preparations showed disruptions of the peripheral actin rim coincident with fluorescein isothiocyanate‐bovine serum albumin leaks, qualitative and quantitative differences were identified.

Conclusions: The results suggest both similar and dissimilar mechanisms for thrombin and histamine regarding in situ endothelial gap formation.
The role of general practitioners’ working style and brief alcohol intervention activity
Authors: Aalto Mauri , Värre Tanja , Pekuri Petteri , Seppä Kaija
Published: October 2003

Aims  To examine correlates of general practitioners’ (GP) activity delivery of brief alcohol interventions to patients with particular reference to their ‘working style’.

Design  A postal questionnaire survey.

Setting and participants  All 75 GPs in the Community Primary Health Care Centre of the City of Tampere, Finland.

Measurements  Measures of working style classifying GPs into ‘problem solving’ versus ‘technological’, self‐reported brief advice activity and other demographic details.

Findings and conclusions  Of the respondents (response rate 85%) 45% (29/64) reported carrying out brief alcohol interventions. Male GPs provided brief interventions more often than female GPs (71% versus 36%, P = 0.017). The respondents had mainly positive attitudes to brief interventions for excessive drinkers. The working style typology did not show any relationship with brief intervention activity.
Effects of cardiac output on disposition kinetics of sorbitol: recirculatory modelling
Authors: WEISS M. , HÜBNER G. H. , HÜBNER I. G. , TEICHMANN W.
Published: October 2003

1 The purpose of this study was to determine the effects of cardiac output on distribution and elimination kinetics of the marker compound sorbitol.

2 The disposition kinetics of sorbitol were investigated after rapid intravenous injection and arterial sampling in nine patients who had undergone cardiac catheterization whereby the cardiac output was measured.

3 A minimal circulatory model consisting of pulmonary and systemic subsystems, both of which were characterized by an inverse Gaussian transit time density function, fitted the data very well. The method involves numerical inverse Laplace transform of the model equations.

4 The mixing clearance introduced as a novel non‐compartmental parameter of distribution dynamics was significantly correlated with cardiac output. The steady‐state volume of 14 l matched the extracellular volume. The systemic extraction ratio of 23% may reflect the fractional liver blood flow.

5 This pharmacokinetic model can be applied when an independent observation of cardiac output is available. In contrast to the conventional compartmental (or sum of exponential) approach it contains fewer adjustable parameters which can be more readily interpreted in physiological terms.