bluuebunny/crossref_metadata_2025_split huggingface dataset:
Poly(silylenemethylene)‐based polymer blends. III. Synthesis and properties of polymer blends containing siloxane‐crosslinked poly(silylenemethylene)s
Authors: Ogawa Takuya , Murakami Masashi 
Published: December 2002

AbstractSoft–hard binary polymer blends consisting of amorphous poly(silylene methylene)s (PSMs) and crystalline poly(diphenylsilylenemethylene) were prepared by both melt processing at 360 °C and in situ polymerization at 300 °C. Linear and siloxane‐crosslinked PSMs were used as amorphous components for the purpose of determining how the crosslinks affected the interactions between the component polymers. Differential scanning calorimetry and dynamic mechanical analysis indirectly suggested that discernable differences between the blends containing linear and crosslinked PSMs were attributable to the degree of interactions between the amorphous and crystalline components. The morphological differences between these blends were studied with transmission electron microscopy. The dispersion phase was smaller in the blends containing crosslinked PSM than that in the blends containing linear PSM. This directly indicated that a larger interaction between the amorphous and crystalline phases was obtained by the introduction of crosslinks because of the smaller viscosity difference between the phases and a larger degree of polymer chain entanglement. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 257–263, 2003
Hydrogen‐bonded thermotropic liquid‐crystalline polyester–amides from bis(hydroxy alkamido)aranes: Synthesis and properties
Authors: Sudha J. D. , Pillai C. K. S. 
Published: December 2002

AbstractHydrogen‐bonded aromatic–aliphatic polyester–amides (PEAs) were prepared by solution/melt polycondensation of aromatic–aliphatic amidodiols 1,4‐bis(4‐hydroxybutyramide)benzene (BHBB), 1,4‐bis(5‐hydroxy pentamide)benzene, 1,4‐bis(6‐hydroxyhexamide)benzene, 1,4‐bis(4‐hydroxybutyramidexylene), 1,4‐bis(5‐hydroxypentamidexylene, 1,4‐bis(4‐hydroxybutyramide)benzene, and 1,4‐bis(6‐hydroxyhexamidexylene) with terephthaloyl chloride/dimethyl terephthalate. Aromatic–aliphatic amido diols were prepared by the aminolysis of γ‐butyrolactone, δ‐valerolactone, and ϵ‐caprolactone with aromatic diamines such as paraphenylene diamine and paraxylene diamine. The monomers and polymers were characterized by chemical analysis (hydroxyl value and elemental analysis), Fourier transform infrared spectroscopy, 1H NMR, and 13C NMR. The thermal‐ and phase‐transition behaviors of the polymers were investigated by differential scanning calorimetry in combination with hot‐stage optical microscopy. Crystallinity of polymers was examined with wide‐angle X‐ray diffraction. The polymers exhibited liquid crystallinity with layered structures formed by self‐organization of the hetero intermolecular hydrogen‐bonded networks indicating smectic phases except for PEAs prepared from BHBB. The hydrogen atom of the phenyl‐substituent group forces the neighboring carbonyl groups out of plane of the rings preventing formation of layered structures in the case of BHBB. The PEAs retained intermolecular hydrogen bonding even in the mesomorphic state, and variations in the hydrogen‐bonded lamellae/micelles might be responsible for the variations from one smectic to another texture. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 335–346, 2003
Synthesis and characterization of photocrosslinkable, side‐chain, second‐order nonlinear optical poly(ester imide)s with great film‐forming ability and long‐term dipole orientation stability
Authors: Lu Jiongxin , Yin Jie 
Published: December 2002

AbstractA series of photocrosslinkable, side‐chain, second‐order nonlinear optical (NLO) poly(ester imide)s (PEIs) based on a chromophore‐containing dianhydride, 2,2′‐{4‐[(4‐nitrophenyl)‐azo]phenyl}iminobis(ethyl benzene‐1,2‐dicarboxylic acid anhydride‐4‐carboxylate), benzophenone‐3,3′,4,4′‐tetracarboxylic dianhydride, and 4,4′‐diamino‐3,3′‐dimethyl diphenylmethane were prepared. The resulting PEIs exhibited many useful physical characteristics, such as good organosolubility, excellent film‐forming properties, high glass‐transition temperatures (186–229 °C), and high thermal decomposition temperatures. The electrooptic coefficient value of PEI3 at 650 nm was 11.5 pm/V, and high long‐term stability of the NLO chromophore alignment in the poled PEI3 film at 120 °C was observed. The temporal stability of the dipole orientation at 150 °C was further enhanced by ultraviolet irradiation because of photocrosslinking. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 303–312, 2003
Biodegradable brushlike graft polymers. I. Polymerization of ϵ‐caprolactone onto water‐soluble hydroxypropyl cellulose as the backbone by the protection of the trimethylsilyl group
Authors: Wang Caiqi , Dong Yuping , Tan Huimin 
Published: December 2002

AbstractAfter the protection of partial hydroxyl groups with trimethylsilyl (TMS) groups, hydroxypropyl cellulose becomes soluble in organic solvents, and the number of hydroxyl groups as initiating groups can be controlled. As a result, a new brushlike graft poly(ϵ‐caprolactone) can be prepared with hydroxypropyl cellulose as the backbone polymer by homogeneous ring‐opening graft polymerization and deprotection. The protection and deprotection of the TMS group during the entire procedure were carefully monitored with Fourier transform infrared (FTIR) and NMR, and the final graft copolymers were characterized with FTIR, 1H NMR, 13C NMR, gel permeation chromatography, and differential scanning calorimetry. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 273–280, 2003
Passive and semi‐active seismic response control of a cable‐stayed bridge
Authors: Iemura Hirokazu , Pradono Mulyo Harris 
Published: December 2002

AbstractEffectiveness of passive and semi‐active seismic response control on a cable‐stayed bridge was studied by numerical analyses. An existing cable‐stayed bridge which has fixed‐hinge connections between deck and towers is modeled and its connections were replaced by isolation bearings and dampers. The isolation bearings are of elastic and hysteretic type. The dampers are of linear and variable type. The variable damper uses semi‐active control that incorporates a pseudo‐negative stiffness algorithm. A pseudo‐negative stiffness hysteretic loop produced by the variable damper, combined with a positive stiffness curve of the deck‐tower connections, creates nearly rigid–perfectly plastic force–deformation characteristics with a large damping ratio. The damping ratio for the main mode of the bridge for both passive and semi‐active control was also calculated. Soil‐structure interaction and three‐dimensional effects on structural responses were studied. Copyright © 2002 John Wiley & Sons, Ltd.
Effect of non‐proportional damping on seismic isolation
Authors: Du Yongfeng , Li Hui , Spencer Billie F. 
Published: December 2002

AbstractThis paper presents several new methods for estimating the maximum seismic responses of non‐proportionally damped two‐degrees of freedom isolation systems. For completeness of the discussion, the formulation, analysis methods, and results are first compared for proportionally and non‐proportionally damped structural systems. The effect of non‐proportional damping on the properties of eigenvalues and eigenvectors of a base‐isolated structure is presented. Several approaches to estimate the maximum response of a two‐degrees of freedom, non‐proportionally damped isolation system are developed, and numerical comparison is made through two examples. Numerical results show that the methods presented in this paper better reflect the optimum isolation damping that results in the minimum superstructure shear force response. Copyright © 2002 John Wiley & Sons, Ltd.
Global warming mode of atmospheric circulation
Authors: Zhu Jinhong , Wang Shaowu , Zhang Xiangdong 
Published: December 2002

AbstractVariations of global zonal‐mean atmospheric circulation are studied using the National Center of Environment Prediction/National Center of Atmosphere Research (NCEP/NCAR) reanalysis data set from January 1948 to February 2001 and CCM3.6 (Community Climate Model Version 3.6) simulations for the period 1900–1999. Empirical orthogonal function (EOF) analysis indicates that variations of zonal‐mean geopotential height in the tropics are usually opposite to those over the subpolar zone in both hemispheres. The first mode of EOF analysis shows that height is higher than normal in the tropics when it is lower over the subpolar zone in both hemispheres with much stronger westerlies over mid latitudes in both hemispheres, and vice versa. This mode explains about 50% variance and is predominant in the whole troposphere. The time series of EOF1 has a sharp transition near about 1977 and the polarity changes from negative to positive. This mode is closely related to the variations of global mean surface air temperature. The detrended correlation coefficient between EOF1 time series and the surface air temperature is 0.74 in the boreal winter. Furthermore, the lowest correlation coefficient among the other three seasons, annual mean, seasonal mean and monthly mean is higher than 0.42 which indicates the fairly good relationship between this mode and the surface air temperature. This result has been verified using CCM3.6 simulations. Copyright © 2002 Royal Meteorological Society.
Skill of statistical interpretation forecasting system during monsoon season in India
Authors: Kumar Ashok , Maini Parvinder , Rathore L. S. , Singh S. V. 
Published: December 2002

AbstractAn evaluation of statistical interpretation(SI) forecast skill for rainfall and maximum/minimum temperature during monsoon season (June–September) is presented. A brief description of the methodology used for SI forecast and data used is also given. The skill of SI forecast is calculated during 1999, monsoon and has been found encouraging. Copyright © 2002 Royal Meteorological Society.
ACTIN‐RELATED PROTEIN (ARP2) INSERTS INTO ARTIFICIAL LIPID MEMBRANES
Authors: Goldmann Wolfgang H. , Isenberg Gerhard 
Published: December 2002

AbstractArp2 is localized in the cytoplasm of eukaryotic cells where it controls actin dynamics. Computer analyses have suggested one possible lipid binding site, residues 185–202 of the primary amino acid sequence on Arp2, that could allow for membrane attachment/insertion. We expressed this region as a fusion protein with schistosomal glutathione S‐transferase (GST) and investigated the interaction of this fragment with mixtures of dioleoylphosphatidylserine (DOPS) and dioleoylphosphatidylglycerol (DOPG) phospholipids in reconstituted lipid bilayers using differential scanning calorimetry (DSC). Calorimetric measurements showed that as the fusion protein increased, the main chain transition enthalpy decreased and the chain‐melting temperature shifted, which is indicative of partial protein insertion into the hydrophobic region of the lipid membrane. This was confirmed using the Langmuir Blodgett technique (film balance) on lipid monolayers. The dissociation constant (Kd) determined by the temperature jump method was approximately 1.1μM.
EXPRESSION AND REGULATION OF SPARC, FIBRONECTIN, AND COLLAGEN IV BY DEXAMETHASONE IN LENS EPITHELIAL CELLS
Authors: Sawhney Rajinder S. 
Published: December 2002

AbstractCataract formation is a deleterious side effect of some hormone therapies, thus, it is important to understand how hormones regulate lens basement structure and function. We have examined the effects of dexamethasone (DEX) on the regulation of Secreted Protein Acidic and Rich in Cysteines (SPARC), fibronectin (FN), and collagen IV (CN IV). To radiolabel newly synthesized proteins, cultured monolayers of bovine anterior lens capsule epithelial (ALCE) cells were pulsed with [3H] proline. To identify proteins, an immunofluorescent technique, immunoprecipitation with specific antibodies, and electrophoretic separation on sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) were used. DEX increased production of total proteins, whereas it specifically decreased synthesis of FN and CN IV. A decrease in FN and CN IV synthesis by DEX in ALCE cells may decrease adhesion of lens epithelium to the basement membrane (BM), which may in turn cause pathogenesis. Messenger RNAs were identified by Northern blot analyses using specific DNA probes. Treatment of lens epithelial cells with DEX causes a 100–150% up‐regulation of SPARC mRNA in a concentration‐dependent fashion. The increase in the expression of FN mRNA by DEX was in a dose‐response fashion and varied from 50–600%. A 24‐hour treatment with DEX (10−6M) increased CN IV mRNA levels to 386% over baseline levels. Thus showing a differential upregulation by DEX of mRNAs of SPARC, FN, and CN IV. Results of nuclear run‐on transcription assays indicate that regulation of RNAs by DEX may occur, in part, at the transcriptional level. The aberrant expression of lens basement membrane proteins by DEX may contribute to abnormal lens cell function and ultimately to anterior subcapsular cataract.
LOCALIZATION OF PAN‐CADHERIN IMMUNOREACTIVITY IN ADULT RAT TISSUES
Authors: Filiz Serdar , Dalcik Hakki , Yardimoglu Melda , Gonca Suheyla , Ceylan Sureyya 
Published: December 2002

AbstractCadherins, being responsible for selective cell recognition and normal tissue integrity in adults, regulate morphogenesis in a variety of organs during development. In this study, anti‐rat pan‐cadherin antibody, specific to all subgroups of the cadherin family, was used to map the distribution of the pan‐cadherin immunoreactivity in adult rat organs. Pan‐cadherin immunoreactivity positive tissues were: secretory cells of the adenohypophysis, autonomic nerve, corneal epithelium, oesophageal nerve plexus, stomach and pyloric glandular cells, epithelium of the ileum and its nerve plexus, alveolar cells of the lung, proximal convoluted tubules of the kidney, islet cells of Langerhans, and the acinar cells of the exocrine pancreas. For the first time, positive pan‐cadherin immunoreactivity was demonstrated in the epithelial cells of the corpus ciliaris and in the nerve plexus of corpus cavernosum of the penis. In conclusion, our results suggest that cells in many tissues and organs of the adult rat synthesize cadherins.
EFFECTS OF TRANSFORMING GROWTH FACTOR‐β1 AND FIBRONECTIN ON SPARC EXPRESSION IN CULTURES OF HUMAN PERIODONTAL LIGAMENT CELLS
Authors: Fujita Tsuyoshi , Shiba Hideki , Sakata Masatoshi , Uchida Yuushi , Ogawa Tetsuji , Kurihara Hidemi 
Published: December 2002

AbstractTransforming growth factor‐β1 (TGF‐β1) increases synthesis of secreted protein, acidic and rich in cysteine (SPARC), as well as fibronectin (FN) and type I collagen. However, little is known about the regulatory mechanism of SPARC expression. We examined the effect of FN on SPARC expression by TGF‐β1 in cultures of human periodontal ligament cells (HPL cells). TGF‐β1 increased the SPARC and SPARC mRNA levels in HPL cells. Extracellular matrix (ECM) produced by HPL cells in the presence of TGF‐β1 also increased the SPARC levels. Contents of FN and type I collagen in the ECM were increased by TGF‐β1. HPL cells cultured on FN‐coated plates secreted more SPARC than those on non‐coated plates. However, type I collagen had little effect on SPARC levels. The addition of anti‐α5 antibody to the cultures abolished the increase in SPARC mRNA expression by TGF‐β1. This study demonstrated that FN may be partly involved in the increase in SPARC expression by TGF‐β1 in HPL cells.
Molecular phylogeny and status of Diploicia and Diplotomma, with observations on Diploicia subcanescens and Diplotomma rivas-martinezii
Authors: Molina María del Carmen , Crespo Ana , Blanco Oscar , Hladun Néstor , Hawksworth David L. 
Published: December 2002

AbstractITS rDNA sequence data shows that Diploicia and Diplotomma species form a monophyletic clade distinct from other Buellia species. This indicates that Diplotomma merits acceptance as a genus, and suggests that Diploicia should be treated as a synonym of Diplotomma, the earlier name. The data also shows Diploicia subcanescens, considered the fertile counterpart in a species pair with D. canescens, is nested within D. canescens and should be treated as a synonym despite reported chemical differences. In addition, the molecular data support the distinctness of Diplotomma rivas-martinezii, a species restricted to gypsum rocks in Spain, from the widespread D. venustum, which grows on calcareous rocks. Aposymbiotic cultures suggest that D. rivas-martinezii also differs from D. venustum in its germination and isolation success rates. One new combination is made: Diplotomnta pulverulenta (Anzi) D. Hawksw. (syn. Abrothallus pulverulentus Anzi) for the lichenicolous species previously known as Buellia pulverulenta.
Pain recurrence: A quality of life issue in endometriosis
Authors: Damario M.A. , Rock J.A. 
Published: December 2002

AbstractStudies reveal endometriosis to be present in 38–51% of women undergoing laparoscopy for chronic pelvic pain. Symptoms attributable to endometriosis include dysmenorrhea, dyspareunia, generalized pelvic pain, dyschezia, and radiation of pain to the back or leg. Psychological factors may also contribute to a more intense pain experience. Medical therapy provides symptom relief in 72–93% of patients, although recurrence is common following treatment discontinuation. Surgical therapy has had varying results for long‐term pain relief; adequacy of the initial surgical treatment appears to be a critical factor. Important adjunctive measures include presacral neurectomy and excisional techniques to remove deep, fibrotic, retroperitoneal lesions. The quality of life of women with endometriosis will improve with greater focus on achieving the long‐term relief of pelvic pain. Limitation of pain recurrence would benefit the patient greatly, by providing symptom relief and preventing the cycle of its probable adverse effects on physical activity, work productivity, sexual fulfilment, and mood.
Synaptic plasticity and tianeptine: structural regulation
Authors: Fuchs E. , Czéh B. , Michaelis T. , de Biurrun G. , Watanabe T. , Frahm J. 
Published: December 2002

SummaryStress-induced structural and cellular alterations in the hippocampus can contribute to the pathophysiology of depression. The reversal of these alterations may be a mechanism by which antidepressants achieve their therapeutic effect. The aim of the present study was therefore to investigate the effect of tianeptine on stress-induced structural changes and alterations in cerebral metabolites. To this end, psychosocially stressed male tree shrews were treated with tianeptine. A combination of in vivo and postmortem methods was used to evaluate the antidepressant treatment on the preservation of neuronal plasticity. It was found that all stress-induced effects were prevented by the administration of tianeptine. It is concluded that these findings provide experimental evidence for recent theories that impairment of neuronal viability and neuroplasticity might be important causal factors in mood disorders, suggesting tianeptine as a potential stimulator of neural resilience.
Beyond the monoamine hypothesis: mechanisms, molecules and methods
Authors: Hindmarch I. 
Published: December 2002

SummaryThe first effective antidepressants (monoamine oxidase inhibitors and tricyclic antidepressants) relied on their ability to augment serotonin and noradrenaline levels at the synapse. Forty years later, the same biological model led to the supremacy of the serotonergic hypothesis to explain not only the pathophysiology of depressive illness, but also the neuropharmacological basis for obsessive compulsive disorder, phobias, posttraumatic stress disorder, and even generalized anxiety disorder. It could be argued that the blinkered view of depression as a solely serotonergic phenomenon has not only restrained and limited research into other potential systems, but has also slowed down the discovery of putative antidepressant drugs. While some might argue that the hypothalamic-pituitary-adrenal (HPA) axis explains an individual’s sensitivity to depression, there are others who equally claim that the most likely explanations are to be found in the neuropsychopharmacology of the immune system or even through reductions in hippocampal volume. There is a richness of possibilities regarding the mechanisms for antidepressant activity embracing theoretical, pharmacological and clinical data. However, the methods by which putative antidepressants are assessed and their clinical efficacy demonstrated are not always robust. That current clinical comparisons of antidepressants rarely show major differences in efficacy between existing molecules could be taken as an indication that “all drugs are the same” or perhaps, more insightfully, as an indication that the ubiquitous Hamilton depression (HAM-D) rating scales are not sensitive to inter-drug differences, even though pronounced pharmacodynamic differences between molecules are easily demonstrated. Any advances in the development of new antidepressants will have to find not only original compounds but also unique psychometric tests by which the drugs can be assessed in a sensitive, reliable, and valid manner.
Modelling a coastal ridging event over south‐eastern Australia
Authors: Reason C. J. C. , Jackson P. L. 
Published: December 2002

AbstractCoastal ridging is an important component of the weather of south‐eastern Australia during the summer. The mesoscale aspects of such an event are often not well forecast, and this can have serious implications for aviation, shipping, air quality and bushfire control. A previous study by Speer & Leslie (1997) identified three types of coastal ridging according to the associated synoptic conditions. In this study, a coastal ridging event, which appears to have aspects of all three types, is examined with the aid of mesoscale manual analyses, surface and radiosonde data and simulations with a mesoscale numerical model (Colorado State University Regional Atmospheric Modeling System).It is found that the model is able to capture the salient features of the event but, on the east coast, tends to produce a weaker event than that observed. The model ridging also tends to lag the observed feature on the east coast by a few hours. It is suggested that these model deficiencies may relate to deficiencies in the lower atmosphere air mass characteristics, which, in turn, may relate to the surface parameterisations in the model. Copyright © 2002 Royal Meteorological Society.
Areal PMP distribution of one‐day to three‐day duration over India
Authors: Clark Rakhecha C P R 
Published: December 2002

AbstractThere is a need to assess the areal depth of the probable maximum precipitation (PMP) over specified catchment areas for the safe construction of dam spillways. The large number of dams in India, coupled with their risk of failure, makes this need imperative both for the maximum use of water resources and for public safety. On the basis of rainfall data for the heaviest storms that occurred in different parts of India during the period 1880–1983, improved estimates of one‐, two‐, and three‐day point PMP for India have been made. In this paper the distribution of areal PMP over specified catchment sizes is provided for the first time. The areal reduction factors (ARF) were based on envelope curves of major storms to give the ARF for areas of 10–20,000 km2 . These factors were found to vary from 1.0 to 0.41, though there was no real difference between durations of rainfall. These values of ARF were then multiplied by values of one‐ to three‐day PMP. The resulting maps allow a broad description of the spatial distribution of areal PMP and also provide a rapid and consistent estimate of the probable maximum flood (PMF) from the PMP.For 500 km2 the areal PMP varies from 40 to 120 cm for one‐day duration; from 70 to 200 cm for twoday duration; and from 75 to 270 cm for three‐day duration. The pattern of PMP is consistent with the geography and available moisture. Copyright © 2002 Royal Meteorological Society.