bluuebunny/crossref_metadata_2025_split huggingface dataset:
Properties of amphoteric polyurethane waterborne dispersions. III. Isoelectric points and precipitation
Authors: Dong Anjie , Hou Guoling , Feng Menghuang , Li Aigui 
Published: October 2002

AbstractThe isoelectric points of amphoteric polyurethane (APU) with hydrophobic soft segments and pendent COOH and CH2N(CH3)2 groups and the effect of inorganic salts on the isoelectric points were investigated by the conductivity titration method. The pH values at isoelectric points agreed with the theoretical isoelectric point equations of Patrickios and Merle with pKa = 6.1 and pKb = 8.3, even though, as an ionomer, APU has a low density of ionizable groups on the macromolecular chains and takes a micellar state in aqueous media. The precipitation of APU waterborne dispersions also was observed around the isoelectric points and around lower or higher pH values with the ultraviolet spectrophotometric method. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2440–2448, 2002
Modification of porous poly(ether sulfone) membranes by low‐temperature CO2‐plasma treatment
Authors: Wavhal Dattatray S. , Fisher Ellen R. 
Published: October 2002

AbstractA general method of modifying the entire cross section of porous poly(ether sulfone) membranes with a low‐temperature CO2‐plasma treatment is reported. Both surfaces of the membranes are highly hydrophilic, with a water drop on the surface disappearing in less than 1 s, even 6 months after plasma treatment. This high hydrophilicity of both membrane surfaces results from the incorporation of hydrophilic functionalities, as evidenced by Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy. The incorporation of these hydrophilic functionalities takes place primarily during plasma treatment, with some incorporation of atmospheric oxygen and nitrogen immediately upon exposure to air. Scanning electron microscopy shows that the membrane surface is covered by a thin, white layer that is likely the result of etching and redeposition of sputtered surface fragments. An increase in the water bubble point and glass‐transition temperature is also observed for CO2‐plasma‐treated membranes. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2473–2488, 2002
Experimental characterization of the volume strain of poly(vinylidene fluoride) in the region of homogeneous plastic deformation
Authors: Quatravaux T. , Elkoun S. , G'Sell C. , Cangemi L. , Meimon Y. 
Published: October 2002

AbstractDamage to poly(vinylidene fluoride) was studied under uniaxial tension testing at different temperatures and strain rates. A satisfactory accuracy was reached with an original procedure for the assessment of the principal strains and volume strain. The semicrystalline polymer exhibited an increase in the volume strain with the true axial strain caused by material damage. This damage depended on the temperature and strain rate and was related to the whitening phenomenon generally observed. The use of the general ideas of Bucknall's model, based on the decomposition of the whole volume strain into three components, allowed the extraction of the component of the volume strain corresponding to microstructural mechanisms of plastic deformation other than shearing. Therefore, nucleation and growth stages of cavitation were revealed. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2516–2522, 2002
Observations on granite weathering phenomena, Mount Keinath, Northern Victoria Land, Antarctica
Authors: French H. M. , Guglielmin M. 
Published: October 2002

AbstractRock varnish, erosional grooves, and well‐developed cavernous weathering phenomena occur in close association on a small biotite‐monzogranite nunatak in the Northern Foothills region, Northern Victoria Land, Antarctica. The grooves, similar in appearance to the ‘rinnenkarren’ described in the karst literature, are developed on steeply inclined (>35°) bedrock surfaces while the rock varnish occurs on adjacent, more gently sloping (<15°) bedrock surfaces. The varnish forms a resistant carapace through which small weathering pits have developed and below which are large cavernously weathered hollows (taffoni). We argue that the intimate association between the grooves and the rock varnish indicate the nunatak has been exposed to a long period of subaerial weathering. The preservation of both phenomena supports (a) the idea that landscape modification in this exceptionally cold and arid region of Antarctica is very slow and (b) the long‐term stability of the Antarctic ice sheet. Copyright © 2002 John Wiley & Sons, Ltd.
The fluvial morphodynamics of two small permafrost drainage basins, Richardson Mountains, Northwestern Canada
Authors: Priesnitz Kuno , Schunke Ekkehard 
Published: October 2002

AbstractBased on hydrological fieldwork in the tundra of northwestern Canada during the springs of 1986, 1990, 1992, and 1994 and the summers of 1998, 1999, and 2000 the paper deals with the fluvial processes induced by spring snowmelt and by summer rainfall in two small stream valleys. At the end of winter the floors of these flat‐bottomed valleys are covered by icings (aufeis) over most of their length. The biggest quantity of meltwater runoff passes in an ice channel on top of the icing, with flow velocities up to 4.8 m/s. The main solid‐sediment transport takes place through the short runoff interval, when the stream channel has entrenched the aufeis in some places. The calculated suspended load transport during snowmelt flood varied from 62–313 t/km2 in different years. In summer, suspended‐sediment transport varies between 0.2–1.4 t/km2. There are no data about the frequency of exceptionally strong precipitation events, similar to those that occurred during the 1999 summer in the Douglas Creek basin that led to a suspended load transport of 153 t/km2 and a bedload transport of 444 t/km2 in about 12 days. The average annual suspended‐sediment yield for Andy Creek is 71 t/km2/yr, and 328 t/km2/yr for Douglas Creek. The average annual solutes yield for Andy Creek is 19 t/km2/yr, and 52 t/km2/yr for Douglas Creek. If one includes the hardly‐recordable bedload transport, the total equivalent surface lowering rate by fluvial solids transport is about 350 mm/1000yr for the Andy Creek basin and 850 mm/1000yr for the Douglas Creek basin. Copyright © 2002 John Wiley & Sons, Ltd.
Inhalation and deposition of nebulized sodium cromoglycate in two different particle size distributions in children with asthma
Authors: Nerbrink O.L. , Lindström M. , Meurling L. , Svartengren M. 
Published: October 2002

AbstractThe relative deposition of two inhaled droplet size distributions of sodium cromoglycate produced by a Hudson Updraft II nebulizer was evaluated, using a setup modified from the proposed Comité Européen Normalisé (CEN) standard prEN 13544‐1. The modified setup comprised an Andersen 296 impactor and a Spira Electro 2 dosimeter. The setup was characterized prior to use in children with sodium cromoglycate (SCG) and sodium fluoride as tracer aerosol. The main in vivo study was designed to allow nine children with a mean age of 10 years to inhale SCG aerosol at two different relative humidities (RH), a high RH (> 90%) and a low RH (13%), which in turn resulted in two different droplet size distributions. The nebulizer/dosimeter was set to provide 1‐sec nebulization during 50 inhalations. Throughout the exposures, the children were instructed to inhale in a consistent manner with target tidal volumes (0.5 L) and inhalation flows (0.4 L/sec). Blood samples were taken at predefined time intervals, and the area under the curve (AUC) was calculated. A lung deposition program, TGLD2, was used to calculate the expected deposition, using the droplet sizes and inhalation parameters obtained during in vivo exposures.The in vivo monitoring of droplet size distribution during the exposure showed that the low, intermediate (room air), and high RHs gave a mean droplet size distribution with a mass median aerosol diameter (MMAD) of 1.2, 1.7, and 2.0 μm, respectively. The average tidal volume over all exposures was 0.51 ± 0.12 L. The total deposition fraction was 33.4% of the estimated nebulizer output. A correlation was found between tidal volume and the calculated deposited fraction.The results indicate that there is a difference in total deposition, depending on the size of the droplet size distribution, with the larger droplet size distribution (MMAD, 2.0 μm) having a higher total deposition than the smaller droplet size distribution (MMAD, 1.2 μm). The deposition results were in good agreement with the deposition fractions estimated using the TGLD2 software for the inhalation parameters found in the study. The obtained study results can arise from differences in regional deposition, but may also be explained by differences in extrathoracic deposition. Pediatr Pulmonol. 2002; 34:351–360. © 2002 Wiley‐Liss, Inc.
Horseshoe lung with pseudo‐ring‐sling complex
Authors: Hwang Haw‐Kwei , Chen Ming‐Ren , Chen Shyh‐Jye , Kao Hsin‐An , Lee Kuo‐Sheng , Shih Shin‐Lin 
Published: October 2002

AbstractWe report on a 1‐month‐old boy who presented with a “horseshoe” lung, complete “O” rings of the trachea, and an unusual course of the left pulmonary artery mimicking a left pulmonary artery sling. Computed tomography, cardiac catheterization, and bronchoscopy were performed to confirm the rare coexistence of these anomalies. To our knowledge, such a combination of anomalies has not been reported in the English‐language literature. Pediatr Pulmonol. 2002; 34:402–404. © 2002 Wiley‐Liss, Inc.
Abernethy malformation: One of the etiologies of hepatopulmonary syndrome
Authors: Alvarez Alfonso E. , Ribeiro Antônio F. , Hessel Gabriel , Baracat Jamal , Ribeiro José D. 
Published: October 2002

AbstractHepatopulmonary syndrome (HPS) is the clinical relationship between hepatic disease and the existence of pulmonary vascular dilatations, which can result in a range of arterial oxygenation abnormalities. It is probably caused by an alteration in the synthesis or metabolism of vasoactive pulmonary substances at a hepatic level, leading to vasodilatation of pulmonary vessels and diffusion perfusion defects. The Abernethy malformation is characterized by the congenital diversion of portal blood away from the liver, by either end‐to‐side or side‐to‐side shunt. Here, we report on a 5‐year‐and‐11‐month‐old‐boy who had started cyanosis at age 4 years and 11 months, and did not have any other pulmonary or cardiac signs or symptoms. In the investigation, arterial blood gases revealed a PaO2 of 41.4 mm Hg. The chest x‐ray film and echo Doppler cardiography were normal. Nuclear scanning with Technetium 99m‐labeled macroaggregated albumin showed the presence of arteriovenous shunt, at 47%. Abdominal echography revealed Abernethy malformation with an absence of portal vein. We concluded that the patient had HPS caused by Abernethy malformation. The possible mechanism is that in this malformation, there is a deviation in the blood that comes from the spleen to the vena cava without passing through the liver, so there is no metabolism of some substances which can be responsible for the imbalance between the vasodilatation and the vasoconstriction of the pulmonary circulation. Abernethy malformation must be included as one of the etiologies of hepatopulmonary syndrome. This is the first case described in the literature with this form of presentation. Pediatr Pulmonol. 2002; 34:391–394. © 2002 Wiley‐Liss, Inc.
bcl‐2 antagonizes the combined apoptotic effect of transforming growth factor‐β and dihydrotestosterone in prostate cancer cells
Authors: Bruckheimer Elizabeth M. , Kyprianou Natasha 
Published: October 2002

AbstractBACKGROUNDWe previously demonstrated that dihydrotestosterone (DHT) enhances transforming growth factor‐β (TGF‐β) ‐induced apoptosis in human prostate cancer cells (Endocrinology 2001;142:2419–2426).METHODSIn this study, the ability of the apoptosis suppressor bcl‐2 to directly antagonize the combined apoptotic effect of TGF‐β and DHT in the androgen‐sensitive LNCaP TβRII prostate cancer cells was examined. The previously cloned TGF‐RβII receptor LNCaP cells, responsive to both TGF‐β and androgens, were engineered to overexpress the bcl‐2 oncoprotein and the profile of apoptosis induction was analyzed in response to TGF‐β alone (5.0 ng/ml) or in combination with DHT (1 nM).RESULTSBiological characterization of cloned LNCaP TβRII hygromycin/bcl‐2 transfectants demonstrated that bcl‐2 overexpression resulted in a significant inhibition of the combined TGF‐β and DHT apoptotic effect in prostate cancer cells (P < 0.01). Furthermore, molecular analysis indicated that this antagonistic effect of bcl‐2 on apoptosis was due to partial suppression of TGF‐β and DHT‐mediated induction of caspase‐1 expression and activation in LNCaP TβRII‐hygro/bcl‐2 transfectants. These results support a potential bcl‐2 interference with the TGF‐β and androgen apoptotic signaling in prostate cancer cells by means of an antagonistic effect on caspase‐1 activation.CONCLUSIONThis evidence may have mechanistic significance in understanding the contribution of bcl‐2 overexpression in the development of androgen‐independent prostate cancer by means of conferring resistance to TGF‐β–mediated apoptosis. Prostate 53: 133–142, 2002. © 2002 Wiley‐Liss, Inc.
Target sites for herbicides: entering the 21st century
Authors: Wakabayashi Ko , Böger Peter 
Published: October 2002

AbstractAt present the use‐rate of modern herbicides is in the range of 100–300 g AI ha−1, with a tendency to decline. The low use‐rate (ca 10 g AI ha−1) of the original sulfonylurea and cyclic imide herbicides prompted agrochemical scientists to look for even more active compounds which led to the successive discoveries of many new herbicidal acetolactate synthase inhibitors and no less than 18 cyclic imides in the class of protoporphyrinogen‐IX oxidase inhibitors in the 1990s. In this paper, mechanisms of action related to function and biosynthesis of chlorophylls, carotenoids, plastoquinone, amino acids, fatty acids and photosynthetic electron transport and other metabolic processes are discussed as plant‐specific herbicidal target domains.© 2002 Society of Chemical Industry
Simple assay for antitumour immunoactive glycoprotein derived from Chlorella vulgaris strain CK22 using ELISA
Authors: Noda Kiyoshi , Tanaka Kuniaki , Yamada Akira , Ogata Jyunko , Tanaka Hiroyuki , Shoyama Yukihiro 
Published: October 2002

AbstractA quantitative ELISA system was developed using a monoclonal antibody (MAb) specific for an antitumour immunoactive glycoprotein (CVS) derived from C. vulgaris strain CK22. The full measuring range of the assay extends from 0.63 to 10.0 ng/mL of CVS. Although no cross‐reaction was observed to proteins tested or other biological response modifiers (BRMs) derived from different sources, cross‐reactions were found with culture supernatants from two other strains of C. vulgaris having a strong antitumour immunoactivity. Treatment of CVS with protease, acid or alkali weakened or completely eliminated the reactivity against the MAb and also its antitumour immunoactivities. This ELISA system is suitable for the biologically active form of CVS derived from C. vulgaris strain CK22 and related immunoactive strains. Copyright © 2002 John Wiley & Sons, Ltd.
Bosons and fermions in a one‐dimensional harmonic oscillator potential
Authors: Wybourne Brian G. 
Published: October 2002

AbstractThe symmetry properties of bosons and fermions in a one‐dimensional harmonic oscillator are explored. It is shown that there is a one‐to‐one correspondence between the counts of the maximal spin states states formed by N‐noninteracting bosons and fermions in a one‐dimensional harmonic oscillator. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002
The origin of spontaneous point mutations in DNA via Löwdin mechanism of proton tunneling in DNA base pairs: Cure with covalent base pairing*
Authors: Kryachko Eugene S. 
Published: October 2002

AbstractThe key aim of the present work is twofold. On the one hand, we propose a novel model of the tautomerization of the A⋅T base pair leading to its mismatches and supporting thus the Löwdin mechanism of the proton transfers taking place within the valley formed by its mispairs. Its specific novelty is actually in that the existing barrier of ca. 23 kcal/mol is not directly related to the proton transfer. Rather, it governs a shift of the bases within the Watson–Crick A⋅T base pair relative to each other and separates it from the valley in its potential energy surface where the mispairing occurs quite easily due to lower barriers of the proton transfers therein. On the other hand, aiming to cure the DNA double helix of generating hydrogen‐bonded mispairs, which lead to the spontaneous point mutations in the genetic alphabet, by inserting covalent base pairs into the DNA architecture, we subject the covalent bond base pair designed recently by Gao and Orgel (Proc Natl Acad Sci USA 1999, 96, 14837) to the high‐level performance computational study. Its three tautomeric forms are found and it is shown that the most stable one is characterized by the amide‐type hydrogen bond. The comparison of the properties such as rotational constants, dipole moment, polarizability, and quadrupole moment is carried out for the Gao–Orgel covalent base pair and the canonical A⋅T one. We demonstrate that the former one can be easily inserted into the double helix DNA without any significant perturbations of the double helix architecture. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002
Growth pattern and bonding of copper clusters
Authors: Jug Karl , Zimmermann Bernd , Köster Andreas M. 
Published: October 2002

AbstractDensity functional theory calculations of copper cluster Cunwithn=2–10 are analyzed with respect to their molecular orbitals. It is shown that shell type orbitals ofs,p, anddcharacter govern the electronic structure growth and have an influence on the geometric structure. They appear as highest occupied molecular orbital, lowest unoccupied molecular orbital, or as orbitals energetically close to these. Their occurrence can explain the magic numbers of shell models. The bonding in such structures can be explained by an analysis of the critical points of the molecular electrostatic potential. Six types of critical points are observed and related to bonds, rings, cages, lone pairs, and their connections. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002
Logarithmic perturbation theory: A reappraisal*
Authors: Bandyopadhyay S. K. , Bhattacharyya K. 
Published: October 2002

AbstractWe present logarithmic perturbation theory in its simplest form that rests only on matching of certain polynomial coefficients at each order. It thus avoids any integration step in the course of calculations of energy correction terms at various orders. The scheme applies to excited states as well. Corrections to nodal point shifts are also obtained without quadratures. A few existing variants of the theory are compared and certain anomalies rectified. Merits and demerits of the approach are pointed out. We also outline a direct route to obtain perturbation series for properties through this route. This renders tedious computations of wave function correction terms at each order, obeying the corresponding normalization requirement, unnecessary, thus achieving further simplification. Pilot calculations on several model systems reveal the worth of the endeavor. © 2002 John Wiley & Sons, Inc. Int J Quantum Chem, 2002
Rapid microorganism identification with on‐slide proteolytic digestion followed by matrix‐assisted laser desorption/ionization tandem mass spectrometry and database searching
Authors: Yao Zhong‐Ping , Afonso Carlos , Fenselau Catherine 
Published: October 2002

AbstractA simple method for microorganism identification is proposed in this paper. In this method, no isolation or fractionation of microorganisms and no special search algorithm or database are needed. Experimentally, a sample of the unfractionated intact microorganism is subjected to brief on‐slide proteolytic digestion and the digestion product ions detected in matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) are selected for tandem mass spectrometry (MS/MS). Database searching using the MS/MS spectrum identifies the microorganism protein, and thereby, according to the source of the protein, the microorganism. The method was demonstrated to be feasible with enterobacteriophage MS2 as the model microorganism. The novel method is simple, rapid, and requires a small quantity of sample. Copyright © 2002 John Wiley & Sons, Ltd.
Planning mobile agent architecture for open network environment
Authors: Hattori Masanori , Ohsuga Akihiko , Honiden Shinichi 
Published: October 2002

AbstractThis paper describes a planning mobile agent architecture proposed for open network environments such as the Internet. Mobile agents in this architecture have mobile, planning, and meta‐level control functionality, and address the locality, variability, and diversity problems to which open network environments are subject. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(12): 58–66, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10112
New directions in nanoscience: new challenges for surface analysis
Authors: Palmer R. E. 
Published: October 2002

AbstractThis paper considers the challenges for surface analysis presented by the creation of new types of nanometre‐scale structure. Such structures, with feature sizes in the range 1–100 nm, are central to the future development of semiconductor chip fabrication and also provide opportunities to address biological problems, especially the structure and function of protein molecules. The analysis of ‘nanostructured surfaces’ is likely to require both the further development of existing surface analysis methods and the invention of new techniques, especially if one wants to address molecular systems that are susceptible to irradiation damage or biological systems whose native environment is aqueous. One example of a new surface analysis technique, scanning probe energy‐loss spectroscopy, is discussed, along with specific ideas for further innovations. Copyright © 2002 John Wiley & Sons, Ltd.
Analysis and TEM examination of corrosion scales grown on Alloy 690 exposed to pressurized water at 325 °C
Authors: Carrette F. , Lafont M. C. , Chatainier G. , Guinard L. , Pieraggi B. 
Published: October 2002

AbstractCorrosion scales grown on Alloy 690 during exposure to pressurized water were examined and analysed by SIMS, scanning electron microscopy (SEM), cross‐sectional transmission electron microscopy (XTEM), XPS and x‐ray diffraction at grazing incidence. All the corrosion tests were performed in pure water on spark‐machined and 1 µm polished specimens at a temperature of 325°C and a pressure of 155 bar. This surface finish results in the formation of a highly defective and thin perturbed zone similar to the standard surface finish of tubes used in pressurized water reactors. Two different testing devices were used: a static autoclave made of stainless steel and a recirculating autoclave made of titanium alloy. Scale thicknesses deduced from XTEM, XPS and SIMS are in good agreement; the average value is ∼50 nm for an exposure of 2160 h. The microstructure of these scales cannot be considered as duplex, as is usually described in the open literature. The scale is formed of a rather continuous and uniform internal Cr‐rich thin layer and an external layer, the composition, morphology and microstructure of which depend on the test conditions and test duration. For example, scales grown in the static autoclave contain higher concentrations of Fe and Ni than scales grown in the recirculating titanium alloy autoclave. Copyright © 2002 John Wiley & Sons, Ltd.