bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct Measurements of HOx Radicals in the Marine Boundary Layer: Testing the Current Tropospheric Chemistry Mechanism
Authors: Kanaya Yugo , Akimoto Hajime 
Published: October 2002

AbstractOH and HO2 radicals, atmospheric detergents, and the reservoir thereof, play central roles in tropospheric chemistry. In spite of their importance, we had no choice but to trust their concentrations predicted by modeling studies based on known chemical processes. However, recent direct measurements of these radicals have enabled us to test and revise our knowledge of the processes by comparing the predicted and observed values of the radical concentrations. We developed a laser‐induced fluorescence (LIF) instrument and successfully observed OH and HO2 at three remote islands of Japan (Oki Island, Okinawa Island, and Rishiri Island). At Okinawa Island, the observed daytime level of HO2 agreed closely with the model estimates, suggesting that the photochemistry at Okinawa is well described by the current chemistry mechanism. At Rishiri Island, in contrast, the observed daytime level of HO2 was consistently much lower than the calculated values. We proposed that iodine chemistry, usually not incorporated into the mechanism, is at least partly responsible for the discrepancy in the results. At night, HO2 was detected at levels greater than 1 pptv at all three islands, suggesting the presence of processes in the dark that produce radicals. We showed that ozone reactions with unsaturated hydrocarbons, including monoterpenes, could significantly contribute to radical production. © 2002 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 2: 199–211, 2002: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.10019
Conjugated Macrocycles as Active Materials in Nonlinear Optical Processes: Optical Limiting Effect with Phthalocyanines and Related Compounds
Authors: Hanack Michael , Dini Danilo , Barthel Markus , Vagin Sergej 
Published: October 2002

AbstractAn overview of the optical limiting (OL) processes in phthalocyanines and related compounds is presented, particularly a description of the synthesis and relevant optical properties of a series of axially substituted indium(III), titanium(IV), phthalo‐ and naphthalocyanines, and octaarylporphyrazines. Several techniques, such as transient absorption, Z‐scan, and degenerate four‐wave mixing, were used to assess the optical properties and OL performance of the investigated compounds. The versatility of the methods of organic synthesis leads to the achievement of effective systems in terms of OL performance through the appropriate combination and modulation of several structural components. The chemistry of the macrocycles here considered allows the variation of the different chemical features, such as the degree of electronic conjugation of the macrocycle and the nature of the ring substituents, the central atom, and the ligands attached to the central atom. © 2002 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 2: 129–148, 2002: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.10024
New Approaches in Radical Carbonylation Chemistry: Fluorous Applications and Designed Tandem Processes by Species‐Hybridization with Anions and Transition Metal Species
Authors: Ryu Ilhyong 
Published: October 2002

AbstractNew approaches in radical carbonylation chemistry are described. We have successfully integrated tin mediated radical carbonylation chemistry into modern fluorous applications and separation techniques. We revealed that radical carbonylation reactions can be performed using fluorous tin mediators, such as fluorous tin hydride and fluorous allyltin reagents. Fine tuning of the reaction conditions resulted in a good efficiency equivalent to conventional tin mediators. The tedious procedure of removing organotin byproducts can be circumvented through the use of fluorous/organic liquid‐liquid extraction or fluorous liquid‐solid phase extraction with fluorous reverse phase silica (FRPS). Also described are newly developed tandem carbonylation reactions that are based on species hybridization approaches. Using a radical/anionic hybrid system based on zinc‐induced one‐electron reduction, we achieved a three‐component coupling reaction consisting of 4‐alkenyl iodides, carbon monoxide, and electron‐deficient alkenes. We observed two types of annulations processes, namely [4 + 1](radical)/[3 + 2](anionic) and [5 + 1](radical)/[3 + 2](anionic), which lead to the production of bicyclo[3.3.0]octanols and bicyclo[3.2.1]octanols, respectively. We found a radical/palladium hybrid system to be useful in the construction of new cyclic systems that incorporate two or three molecules of carbon monoxide. © 2002 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 2: 249–258, 2002: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.10026
Determination of chiral ratio of o,p‐DDT and o,p‐DDD pesticides on polysaccharides chiral stationary phases by HPLC under reversed‐phase mode
Authors: Ali Imran , Aboul‐Enein Hassan Y. 
Published: October 2002

AbstractA simple and reliable HPLC method for the chiral resolution of o,p‐DDT and o,p‐DDD is described. The enantiomeric resolution of o,p‐DDT and o,p‐DDD has been achieved on Chiralpak AD‐R, Chiralcel OD‐R, and Chiralcel OJ‐R chiral stationary phases. The mobile phases used were acetonitrile–water (50:50 [v/v]) and acetonitrile‐2‐propanol (50:50 [v/v]) at a flow rate of 1.0 mL/min. For both pesticides detection was done at 220 nm. The values for o,p‐DDT of α and Rs varied from 1.24 to 2.52 and from 0.80 to 2.47, respectively. The values of α and Rs for o,p‐DDD were 1.26 and 0.60, respectively. © 2002 Wiley Periodicals, Inc. Environ Toxicol 17: 329–333, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/tox.10069
The nebulous art of using wind tunnel aerofoil data for predicting rotor performance
Authors: Tangler James L. 
Published: October 2002

AbstractThe objective of this study was threefold: to evaluate different two‐dimensional S809 aerofoil data sets in the prediction of rotor performance; to compare blade element momentum rotor predicted results with lifting surface, prescribed wake results; and to compare the NASA Ames combined experiment rotor measured data with the two different performance prediction methods. The S809 aerofoil data sets evaluated included those from Delft University of Technology, Ohio State University and Colorado State University. Substantial differences in prediction performance resulted from the different two‐dimensional aerofoil data sets. Predicted performance comparison with NASA Ames data documents shortcomings of these methods and recommends the use of the lifting surface, prescribed wake method over blade element momentum theory for future analytical improvements. Copyright © 2002 John Wiley & Sons, Ltd.
Analyses of the stained glasses of Certosa di Pavia
Authors: Bonizzoni L. , Galli A. , Milazzo M. 
Published: October 2002

AbstractIn the planned restoration of the stained glass windows of the ‘Certosa di Pavia’ presently in progress, systematic elemental energy‐dispersive x‐ray fluorescence (XRF) analysis of glasses has been undertaken on the request of ‘Soprintendenza per i Beni Ambientali e Architettonici’. Analyses of fragments from the first two window‐panes (‘S. Girolamo’ and ‘Presepe’) have been performed. For homogeneous glass samples, quantitative analyses have been obtained by using a secondary XRF set‐up and applying the method of measuring Compton scattering intensity to evaluate self‐absorption corrections. This procedure proved to be effective, as it was checked after comparisons with several standard glass analyses. Also, lateral cross‐sections of each sample have been examined by a 100 µm capillary x‐ray microprobe, so that elements characteristic of glass composition can be discriminated from those due to surface contamination (from lead bindings, for instance). X‐ray microprobe was also a method suited for analyses of layered glasses, as well as spotted small areas or grisaille zones. Copyright © 2002 John Wiley & Sons, Ltd.
Reproductive endocrine patterns in captive female and male red wolves (Canis rufus) assessed by fecal and serum hormone analysis
Authors: Walker S.L. , Waddell W.T. , Goodrowe K.L. 
Published: October 2002

AbstractReproductive steroid profiles in female (n=13) and male (n=5) red wolves (Canis rufus) were characterized in fecal samples collected during the breeding season (December—May) and over a 1 year period, respectively. Blood samples from females (n=12) also were collected during the periovulatory period for luteinizing hormone (LH) and steroid analysis. High performance liquid chromatography (HPLC) of fecal extracts determined that estradiol and estrone constituted the major and minor forms, respectively, of fecal estrogen metabolites. Although native progesterone was present, pregnane metabolites predominated as the major forms of fecal progestins. HPLC analysis of fecal extracts from males revealed no native testosterone, but rather the predominance of more polar androgen metabolites. Based on hormone profiles and/or pup production, females were classified as pregnant (n=3), ovulatory‐nonpregnant (n=9), or acyclic (n=3). Longitudinal monitoring of females indicated no pregnancy‐specific differences in concentrations of either fecal progestagen or estrogen metabolites compared to ovulatory‐nonpregnant individuals; however, baseline progestagen concentrations were consistently elevated in acyclic females. There was good correspondence between serum and fecal steroid concentration during the periovulatory period. A rise in serum estrogens preceded the ovulatory LH surge which was then followed by a significant progesterone rise during the luteal phase. In males, changes in fecal androgen metabolite concentrations coincided with photoperiod fluctuations, increasing in late autumn and reaching peak concentrations during mid‐ to late winter just before the start of the breeding season. Collectively, these results serve as a database of ovarian and testicular endocrine events in this species, which can be utilized in population management and application of assisted reproductive technologies. Zoo Biol 21:321–335, 2002. © 2002 Wiley‐Liss, Inc.
Velocity spectra over different terrains
Authors: Al‐Jiboori M. H. , Xu Yumao , Qian Yongfu 
Published: October 2002

AbstractPower spectra of longitudinal and vertical components of wind velocity have been measured over a variety of terrain types: uniform, inhomogeneous and urban. The result shows that the spectral shapes and peaks of u‐spectra are sensitive to local terrain, while those of w‐spectra are not affected by changes in roughness surface. Copyright © 2003 Royal Meteorological Society.
Intracellular coordination by the ultradian clock.
Authors: Lloyd David , Kippert Fred 
Published: October 2002

AbstractThe time structure of a biological system is at least as intricate as its spatial structure. Whereas we have detailed information about the latter, our understanding of the former is still rudimentary. As techniques for monitoring intracellular processes continuously in single cells become more refined, it becomes increasingly evident that periodic behaviour abounds in all time domains. Timekeeping is essential for synchronization and coordination of intracellular processes. The presence of a temperature‐compensated oscillator provides such a timer. The coupled outputs (epigenetic oscillations) of this ultradian clock constitute a special class of ultradian rhythm. These are undamped and endogenously driven by a device which shows biochemical properties characteristic of transcriptional and translational elements. Energy‐yielding processes, protein turnover, motility, and the timing of the cell division cycle processes, are all controlled by the ultradian clock. Different periods 30 min‐4h characterize different species.
The ERE‐like sequence from the promoter region of the testis specific HSP70‐related gene is not estrogen responsive.
Authors: Krawczyk Zdzislaw , Schmid Wolfgang , Härkönen Pirkko , Wolniczek Piotr 
Published: October 2002

AbstractThe 5′flanking region of the hsp70‐related gene which is specifically expressed in rat and mouse spermatocytes contains the GGTCAnnnCGACC sequence closely resembling the palindromic consensus ERE (estrogen responsive element, GGTCAnnnTGACC). We used a transient expression assay to study whether this ERE‐like sequence can transfer estrogen responsiveness either to heterologous or homologous promoters linked to a reporter CAT gene. We found that the GGTCAnnnCGACC sequence either as an isolated element or in its natural sequence context does not respond to hormone stimulation in MCF‐7 and Fe33 cells. This observation points to the importance of the T‐nucleotide in a right half‐palindrome of ERE for ligand‐dependent activation of transcription.
Relationship between multidrug resistance, hypersensitivity to resistance modifiers and cell volume in Chinese hamster ovary cells.
Authors: Vickers S. E. , Stow M. W. , Warr J. R. 
Published: October 2002

AbstractWe have previously shown that very high levels of hypersensitivity to several resistance modifiers are correlated with increasing multidrug resistance in a series of Chinese hamster ovary cell lines. We have now selected a new member of the series which is an exception to this correlation in that although it is almost twice as multidrug resistant as the cell line from which it was derived, it shows much less hypersensitivity to resistance modifiers.Level of resistance modifier hypersensitivity correlated with the level of reduction of verapamil accumulation in these cells, and with the density of P‐glycoprotein, but since the selection of this cell line has involved a doubling of cell volume, it was not correlated with total amount of P‐glycoprotein.
Search for functional significance of peptidylarginine deiminase in rat pituitaries: variation during pregnancy and ultrastructural localization in prolactin cells
Authors: Akiyama Kyoichi , Nagata Saburo , Tanaka Shigeyasu , Inoue Kinji , Watanabe Kazutada , Senshu Tatsuo 
Published: October 2002

AbstractWe have studied the expression of peptidylarginine deiminase in rat pituitaries during pregnancy. Both the enzyme protein and its mRNA decreased to low levels after the onset of gestation. Both started to increase markedly during mid pregnancy reaching their maxima on day 18 and declined thereafter. The early phase of variations were accompanied with a progressive decrease in the pituitary prolactin content, an abrupt decrease in the prolactin mRNA content, and a small but significant increase in the serum estrogen. We also performed an immunoelectron microscopic study of the enzyme, and showed its scattered localization in the cytoplasm of prolactin cells.
Cholesterol, triacylglicerols and phospholipids during Xenopus embryo development
Authors: Rizzo Angela M. , Gornati Rosalba , Galli Carlo , Bernardini Giovanni , Berra Bruno 
Published: October 2002

ABSTRACTCholesterol, triacylglicerol and phospholipid content was analysed in Xenopus embryos during their early development (from day 1 to day 6). Triacylglicerols decrease significantly during the analysed stages and this can be explained by their use as energy substrate. Cholesterol and phospholipids, on the contrary, remain constant and are probably redistributed inside the embryo. The different phospholipid classes were separated by HPTLC. A constant decrease of PC and a marked increase of PS has been observed. The fatty acid composition of the single phospholipid classes has been analysed.
Plasma membrane transformation: a common response of uterine epithelial cells during the peri‐implantation period
Authors: Murphy Christopher R. , Shaw Timothy J. 
Published: October 2002

AbstractThe plasma membrane of uterine epithelial cells and its changes during early pregnancy are reviewed. The review first examines morphological alterations in rats and mice and laboratory rodents and finds that similar changes in membrane organization accompany the peri‐implantation period: long, thin, regular microvilli are gradually converted into irregular, flattened projections. It is also found however, that in many other species related plasma membrane alterations are seen during early pregnancy. Molecular alterations in the membrane are also examined and although the evidence is so far limited, striking similarities are noted across species. The review also examines some new morphological studies on the alterations in the plasma membrane of uterine epithelial cells during early pregnancy and concludes that a process of plasma membrane transformation may be a common response across species.
Effect of pentoxifylline, a multidrug resistance reversal agent, on haemopoietic stem cell homing.
Authors: Gude R. P. , Chitnis M. P. , Rao S. G. A. 
Published: October 2002

ABSTRACTThis paper investigates the mechanism of mouse haemopoietic stem cell homing into the cytoskeleton depolymerising agent Pentoxifylline was used, and shown to inhibit stem cell homing. The inhibition was reversible after 6 hours. The results obtained suggest that the haemopoietic stem cell homing receptor is anchored to cytoskeletal support intracellularly.
Increased secretion of latent elastase activity following contact between human skin fibroblasts and elastin derived peptides.
Authors: Landeau Jean‐Marie , Pellat Bernard , Hornebeck William 
Published: October 2002

ABSTRACTElastin‐derived peptides were previously shown to influence human skin fibroblasts (HSF) chemotaxis and proliferation (Ghuysen et al., 1992). We report here that culturing HSF on κ‐elastin (κE) but not onto fibronectin (FN) enhanced the secretion of latent elastinolytic activity. The proteinase involved was identified as the 72 kDa gelatinase A. Moreover, HSF‐κE as well as HSF‐FN interactions modulated the secretions of Il1 induced expressions of elastinolytic activities.
Efficient MHC Class II‐restricted presentation of measles virus to T cells relies on its targeting to its cellular receptor human CD46 and involves an endosomal pathway
Authors: Gerlier D. , Trescol‐Biémont M.‐C. , Varior‐Krishnan G. , Naniche D. , Fugier‐Vivier I. , Rabourdin‐Combe C. 
Published: October 2002

ABSTRACTThe role of the measles virus (MV) receptor, human CD46, in the uptake of MV and antigen presentation by Major Histocompatibility Complex (MHC) class II molecules was investigated. Expression of CD46 in murine B cells resulted in cells highly efficient in capturing UV‐inactivated MV particles and presenting both envelope hemagglutinin H and nucleoprotein N to specific T cell hybridomas. Although MV fuse with the plasma membrane of its target cells, presentation of both MV‐H and ‐N was sensitive to inhibition by chloroquine but was not affected by a tripeptide which prevents virus‐cell fusion. Whereas 50 μM of chloroquine was required to inhibit presentation of MV‐H, purified H or soluble N, only a two‐fold lower concentration was required to inhibit that of MV‐N. This shows that some CD46‐mediated captured MV particles are endocytosed, then disrupted and processed in an endosome/lysosome compartment.
The influence of maternal nicotine exposure on the interalveolar septal status of neonatal rat lung.
Authors: Maritz G. S. , Thomas R.‐A. 
Published: October 2002

ABSTRACTThe aim of this study was to determine the effect of maternal nicotine exposure (1 mg nicotine/kg body mass/day, subcutaneously) on the status of the alveolar septa of the 1 to 21 day old offspring. The data obtained showed swelling of type II and interstitial cell mitochondria. The type I:type II cell ratio decreased as a result of type II cell proliferation. The number of capillaries per unit length of septum was also significantly lower than that of control lung. Ruptured blood‐air barriers also occur in the nicotine exposed lungs of rats of all age groups. The results show that maternal nicotine exposure interfered with the morphometric and morphologic characteristics of the septa of lung tissue of the offspring.
Role of feeder cells in spreading and cytoskeleton organization of newborn rat keratinocytes.
Authors: Gorelik J. V. , Blinova M. I. , Diakonov I. A. , Kukhareva L. V. , Pinaev G. P. 
Published: October 2002

AbstractWe studied the effect of feeder cells (fibroblasts) and a mixture of the extracellular matrix components, Matrigel, on spreading and cytoskeleton organization of newborn rat keratinocytes (REK). REK formed lamellipodia on being plated together with feeder cells and on the Matrigel as a substrate whereas the same REK plated alone on a plastic surface formed filopodia. REK lamellipodia formation in co‐cultures depended on the fibroblast addition time. Although conditioned medium from fibroblast cultures was not enough to induce lamellipodia, the extracellular matrix left after fibroblast removal was as effective as Matrigel. Our results indicate that lamellipodia formation seems to depend on the factor(s) secreted by fibroblasts and associated with the extracellular matrix.
The cell and the organism: the role of subdivisional cell replication in the development and maintenance of the multicellular organism
Authors: Okun Milton R. , Edelstein Leon M. 
Published: October 2002

AbstractEvidence of new cell formation from nucleoli (subdivisional cell replication) was observed in vitro and in vivo. Mouse melanoma cells, human fibroblasts, and rat mast cells were observed in tissue culture with phase contrast time‐lapse cinematography. Evidence of subdivisional cell replication seen in tissue culture was supported by observations of mast cells, cervical epithelial cells, melanoma cells, keratinocytes, and fungal spores in vivo. Indirect evidence for subdivisional cell replication was the presence of differentiated form and function in nuclei and nucleoli. Synergism between subdivisional replication and mitotic replication (subdivisional expansion) is believed to be a key to morphogenesis, whereby cellular and subdivisional zones act as biologic "molds". It is believed that subdivisional cell replication has a key role in maintenance of differentiated form in multicellular organisms, as well as in morphogenesis.
Effects on properties of a thiol protease from Xenopus embryos of changes in substrate and assay conditions.
Authors: Miyata Shohei , Nishibe Yasuo , Kihara Hirozi K. 
Published: October 2002

ABSTRACTA protease was purified from Xenopus embryos. Proteolytic activity of the protease against BSA had an optimum pH of 3.8 in acetate buffer and was not detectable at neutral pH. However, when embryonic proteins were used as substrates and digested in phosphate buffer, proteolysis of embryonic proteins was enhanced and was detectable from pH 5.0 to pH 7.0. Digestion of three proteins were mainly detected in digestion of total embryonic proteins. The proteins digested had the same mobilities (on SDS polyacrylamide gel) as yolk proteins. The protease was present in the cytoplasm and around yolk granules. We propose that this protease mainly cleaves a certain yolk proteins in the cytoplasm of Xenopus embryos.
Fibroblast growth factors: at the heart of angiogenesis.
Authors: Slavin J. 
Published: October 2002

ABSTRACTAcidic fibroblast growth factor (FGF‐1) and basic fibroblast growth factor (FGF‐2) are ubiquitous cytokines found in many tissues. They have effects on multiple cell types derived from mesoderm and neuroectoderm, including endothelial cells. In this review the structure and function of the fibroblast growth factor family and its receptors are described. The evidence implicating both FGF‐1 and FGF‐2 in the control of blood vessel formation is presented and their involvement in normal and pathological angiogenesis during adult life is then described in more detail.