bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cysteine enhances clastogenic activity of dimethylarsinic acid
Authors: Kitamura Mari , Kuroda Koichi , Endo Yoko , Endo Ginji 
Published: August 2002

AbstractThe effects of cysteine on dimethylarsinic acid (DMA)‐induced cytotoxicity and chromosomal aberration were studied using Chinese hamster V79 cells. The IC 50 of DMA, i.e. the concentration resulting in a 50% decrease in cell population of viable cells, was 130 µg ml−1 (0.94 mM), whereas that in the presence of 50 µg ml−1 (0.28 mM) cysteine was 20 µg ml−1 (0.14 mM). The mitotic index with co‐administration of 50 µg ml−1 (0.36 mM) DMA and 50 µg ml−1 cysteine was 1.4 times that with 50 µg ml−1 DMA alone. Whereas 82% of cells divided twice with 25 µg ml−1 (0.18 mM) DMA alone, most cells divided only once with co‐administration of 25 µg ml−1 DMA and 50 µg ml−1 cysteine. These results indicated that the increase in mitotic index by cysteine was due to enhancement of mitotic arrest by DMA. With co‐administration of 25 µg ml−1 DMA and 50 µg ml−1 cysteine, tetraploidy was 14.3% higher and fivefold by that with 25 µg ml−1 DMA only. Cysteine at 50 µg ml−1 enhanced induction of chromosomal aberrant cells by DMA. 100 µg ml−1 (0.72 mM) DMA induced 91% chromosomal aberrant cells in the presence of cysteine, and 12% in the absence of cysteine. Chromatid breaks and chromatid gaps were the most frequent types of aberration induced by co‐administration of DMA and cysteine or DMA alone. Co‐administration of DMA and cysteine produced many attenuated chromosomal figures. The attenuated chromosomal figures always had several chromatid gaps and chromatid breaks. Our findings may provide clues to arsenic carcinogenesis in humans. Copyright © 2002 John Wiley & Sons, Ltd.
A study on weld line morphology and mechanical strength of injection molded polystyrene/poly(methyl methacrylate) blends
Authors: Guo Shaoyun , Ait‐Kadi A. 
Published: August 2002

AbstractIn this work, the mechanical strength and weld line morphology of injection molded polystyrene/poly(methyl methacrylate) (PS/PMMA) blends were investigated by scanning electron microscopy (SEM) and mechanical property test. The experimental results show that the tensile strength of PS/PMMA blends get greatly decreased due to the presence of the weld line. Although the tensile strength without the weld line of PS/PMMA (70/30) is much higher than that of the PS/PMMA (30/70) blend, their tensile strength with weld line shows reversed change. The viscosity ratio of dispersed phase over matrix is a very important parameter for control of weld‐line morphology of the immiscible polymer blend. In PS/PMMA (70/30) blend, the PMMA dispersed domains at the core of the weld line are spherically shaped, which is the same as bulk. While in the PS/PMMA (30/70) blend, the viscosity of the dispersed PS phase is lower than that of the PMMA matrix, the PS phase is absent at the weld line, and PS particles are highly oriented parallel to the weld line, which is a stress concentrator. This is why weld line strength of PS/PMMA (30/70) is lower than that of PS/PMMA (70/30) blend. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1856–1865, 2002; DOI 10.1002/app.10450
Oligomeric benzoin photoinitiators
Authors: Kizilcan Nilgün , Akar Ahmet 
Published: August 2002

AbstractNovel oligomeric photoinitiators were synthesised by reacting benzoin with isophorone diisocyanate‐terminated oligomers of dihydroxy‐terminated depolymerization products of polyethylene terephthalate (PET). PET was depolymerized by ethylene glycol (EG), hexylene glycol (HG), polyethylene glycol 10 000 (PEG), and α, ω‐dihydroxy poly(dimethyl siloxane)s (PDMS). Oligomeric photoinitiators were used as free radical initiators for polymerization of styrene and acrylonitrile. Formation of block copolymers was illustrated by several characterisation methods such as FTIR, 1H‐NMR, DSC, and GPC. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 500–508, 2002
High solids content emulsions. IV. Improved strategies for producing concentrated latices
Authors: Schneider M. , Graillat C. , Guyot A. , Betrémieux I. , McKenna T. F. 
Published: August 2002

AbstractA new means of producing high solids content latices with low viscosity is presented. The replacement of water‐soluble initiators that decompose to give charged free radicals is shown to perturb the stability of highly concentrated latices. Their replacement by an oil‐soluble initiator during particle growth, then by an activated, water‐soluble system to remove residual monomer has been shown to help significantly reduce the number of stable particles generated by homogeneous nucleation. Latices with 73% (v/v) solids have been produced with a bimodal particle size distribution (PSD) consisting of 900 and 110 nm particles. The viscosity of these latices can be as low as 300 mPa s−1 at 20 s−1. Despite the presence of water‐soluble monomers, excellent control over the evolution of the PSD allows one to obtain highly reproducible results. In addition, latices produced with the new initiator system have a much lower water uptake and their viscosity is much less sensitive to changes in pH than is the case for latices produced using standard emulsion polymerization techniques. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1935–1948, 2002; DOI 10.1002/app.10514
The effects of ultrasonic irradiation on the crystalline structures of nucleated polypropylene
Authors: Cao Yurong , Xiang Ming , Li Huilin 
Published: August 2002

AbstractThe effects of ultrasonic irradiation on crystallization behavior of polypropylene (PP)‐loaded fillers with nucleating activities, such as sodium benzoate, talc (P), talc (A), and mica, are examined. DSC and WAXD analyses demonstrate that the crystalline structure of PP is changed through ultrasonic vibration. Different nucleating systems have their own specific responses to ultrasound. In sodium benzoate‐added PP, β‐crystal appears when ultrasonic with an appropriate intensity was applied, which alters the growth of PP crystals and favors a special crystal transformation (α→β). On the other hand, ultrasonic does not induce β‐form in the talc or mica system, but prefers crystal growth of (040) plane. Based on the crystalline structure and structures of nucleating agents, the ultrasonic effects in determination of the crystalline preferential growth are analyzed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1956–1961, 2002; DOI 10.1002/app.10516
Effects of a hindered phenol compound on the dynamic mechanical properties of chlorinated polyethylene, acrylic rubber, and their blend
Authors: Wu Chifei 
Published: August 2002

AbstractThe dynamic mechanical properties of binary hybrids of chlorinated polyethylene (CPE) and acrylic rubber (ACM) with 3,9‐bis{1,1‐dimethyl‐2[β‐(3‐tert‐butyl‐4‐ hydroxy‐5‐methylphenyl)propionyloxy]ethyl}‐2,4,8,10‐tetraoxaspiro[5,5]‐undecane (AO‐80) and their ternary hybrids were investigated. The addition of AO‐80 was successful in tailoring the damping profile. The ACM/AO‐80 hybrids show only one relaxation, which is larger than that of pure ACM, whereas for the CPE/AO‐80 hybrids, one novel relaxation appears above the glass‐transition temperature of CPE. In the case of CPE/AO‐80/ACM, a supramolecular network was formed by a crosslink due to hydrogen bonding. The replacement of a part of CPE by ACM increased the value in the middle of two peaks. The AO‐80 molecule, which is a bifunctional hydrogen‐bonding acceptor, was found to act as a compatibilizer. In addition, in such ternary hybrids, the tan δ value in the middle of the two peaks was found to be proportional to the slope of the E′ curve at an identical temperature. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2468–2473, 2001
Copolymerization of 2‐(N‐phthalimido)ethyl methacrylate with glycidyl methacrylate: Synthesis, characterization, and monomer reactivity ratios
Authors: Senthilkumar U. , Balaji R. , Nanjundan S. 
Published: August 2002

AbstractA phthalimido group containing methacrylate based monomer 2‐(N‐phthalimido)ethyl methacrylate (NPEMA) was synthesized by reacting 2‐(N‐phthalimido)ethanol (NPE) with methacryloyl chloride. NPE was prepared by reacting phthalic anhydride dissolved in dimethyl formamide (DMF) with ethanolamine. Homopolymer of NPEMA and copolymers of NPEMA and glycidyl methacrylate (GMA) having various feed compositions were synthesized in methyl ethyl ketone (MEK) solution using benzoyl peroxide as an initiator at 70 ± 1°C. The polymers were characterized by IR and 1H‐NMR spectral studies. The composition of the copolymers was also determined by 1H‐NMR analysis. The reactivity ratios of the monomers were determined by the application of Fineman‐Ross and Kelen‐Tüdös methods. The molecular weights (M̄w and M̄n) and polydispersity index of the polymers were determined using gel permeation chromatography. Thermogravimetric analysis of the polymers was carried out in air and their thermal stability was studied. The solubility and intrinsic viscosity of the homo‐ and copolymers were also studied. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 96–103, 2001
Durable flame‐retardant treatment of polyethylene terephthalate (PET) and PET/cotton blend using dichlorotribromophenyl phosphate as new flame retardant for polyester
Authors: Kim Yoo‐Hun , Jang Jinho , Song Kyong‐Geun , Lee Eui‐So , Ko Sohk‐Won 
Published: August 2002

AbstractDichlorotribromophenyl phosphate (DCTBPP) was synthesized via the reaction of tribromophenol and phosphorous oxychloride and characterized by elemental analysis, IR, 1H‐NMR, thermogravimetric analysis, and differential scanning calorimetry. To impart durable flame retardancy the poly(ethylene terephthalate) (PET) fabric was treated with DCTBPP via pad–dry–thermosol fixation and the PET/cotton (50/50) blend fabric was treated with both DCTBPP and tetrakis(hydroxymethyl) phosphonium chloride (THPC)/urea precondensate via a two‐bath sequential treatment. The treated PET fabric's increased limiting oxygen index value was proportional to the increasing DCTBPP application level and showed self‐extinguishing properties at 8.1% add‐on, even after 50 washes. The blend fabric treated with 15% DCTBPP and 30% THPC/urea precondensate became self‐extinguishable and durable to 50 washes, and the treated fabric retained over 85% of its breaking strength without excessive stiffness. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 793–799, 2001
12‐crown‐4–ether and tri(ethylene glycol) dimethyl–ether plasma‐coated stainless steel surfaces and their ability to reduce bacterial biofilm deposition
Authors: Denes Agnes R. , Somers Eileen B. , Wong Amy C. L. , Denes Ferencz 
Published: August 2002

AbstractIt has been demonstrated that surfaces coated with poly(ethylene glycol) (PEG) are capable of reducing protein adsorption, bacterial attachment, and biofilm formation. In this communication cold‐plasma–enhanced processes were employed for the deposition of PEG‐like structures onto stainless steel surfaces. Stainless steel samples were coated under 1,4,7,10‐tetraoxacyclododecane (12‐crown‐4)–ether and tri(ethylene glycol) dimethyl ether (triglyme)–radio frequency (RF)–plasma conditions. The chemistry and characteristics of plasma‐coated samples and biofilms were investigated using electron spectroscopy for chemical analysis (ESCA), atomic force microscopy (AFM), and water contact angle analysis. ESCA analysis indicated that the plasma modification resulted in the deposition of PEG‐like structures, built up mainly of –CH2CH2O– linkages. Plasma‐coated stainless steel surfaces were more hydrophilic and had lower surface roughness values compared to those of unmodified substrates. Compared to the unmodified surfaces, they not only significantly reduced bacterial attachment and biofilm formation in the presence of a mixed culture of Salmonella typhimurium, Staphylococcus epidermidis, and Pseudomonas fluorescens but also influenced the chemical characteristics of the biofilm. Thus, plasma deposition of PEG‐like structures will be of use to the food‐processing and medical industries searching for new technologies to reduce bacterial contamination. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3425–3438, 2001
Nonisothermal crystallization kinetics of polyoxymethylene/montmorillonite nanocomposite
Authors: Xu W. , Ge M. , He P. 
Published: August 2002

AbstractThe nonisothermal crystallization kinetics of polyoxymethylene (POM), polyoxymethylene/Na–montmorillonite (POM/Na–MMT), and polyoxymethylene/organic–montmorillonite (POM/organ–MMT) nanocomposites were investigated by differential scanning calorimetry at various cooling rates. The Avrami analysis modified by Jeziorny and a method developed by Mo were employed to describe the nonisothermal crystallization process of POM/Na–MMT and POM/organ–MMT nanocomposites. The difference in the values of the exponent n between POM and POM/montmorillonite nanocomposites suggests that the nonisothermal crystallization of POM/Na–MMT and POM/organ–MMT nanocomposites corresponds to a tridimensional growth with heterogeneous nucleation. The values of half‐time and the parameter Zc, which characterizes the kinetics of nonisothermal crystallization, show that the crystallization rate of either POM/Na–MMT or POM/organ–MMT nanocomposite is faster than that of virgin POM at a given cooling rate. The activation energies were evaluated by the Kissinger method and were 387.0, 330.3, and 328.6 kJ/mol for the nonisothermal crystallization of POM, POM/Na–MMT nanocomposite, and POM/organ–MMT nanocomposite, respectively. POM/montmorillonite nanocomposite can be as easily fabricated as the original polyoxymethylene, considering that the addition of montmorillonite, either Na–montmorillonite or organ–montmorillonite, may accelerate the overall nonisothermal crystallization process. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2281–2289, 2001
Porcine enamel matrix derivative enhances trabecular bone regeneration during wound healing of injured rat femur
Authors: Kawana Fumi , Sawae Yoshiko , Sahara Takako , Tanaka Shinpei , Debari Kazuhiro , Shimizu Miho , Sasaki Takahisa 
Published: August 2002

AbstractTo elucidate the effects of enamel matrix derivative (EMD: Emdogain®) on bone regeneration in rat femurs after drill‐hole injury, defects in bone were filled with either EMD or its carrier, PGA, as control. On postoperative days 4 to 28, dissected femurs were examined by means of various morphological approaches. In both experimental groups, formation of trabecular bone, which was immunostained for bone sialoproteins (BSP), had occurred in the medullary cavities at cylindrical bone defects on Day 7 postoperatively. Cuboidal osteoblasts were clearly observed on these newly‐formed BSP‐positive bone trabeculae. On Days 7 and 14, many multinucleated giant cells, which strongly expressed cathepsin K, had appeared on these bone trabeculae, indicating active bone remodeling. In these bone trabeculae, Ca and P weight % and Ca/P ratio were similar to those of cortical bone, and there was no significant difference between the PGA‐ and EMD‐applied groups. Bone volume fraction of newly‐formed bone trabeculae on Day 7 postoperatively was significantly higher in the EMD‐applied group than in the PGA‐applied controls. Because of active bone remodeling and the marked decrease of bone volume, on Days 14 and 28 postoperatively, however, there was no longer a significant difference in trabecular bone volume fraction between the experimental groups. Our results suggest that EMD possesses an osteo‐promotive effect on bone and medullary regeneration during wound healing of injured long bones. Anat Rec 264:438–446, 2001. © 2001 Wiley‐Liss, Inc.
Development and maturation of taste buds of the palatal epithelium of the rat: Histological and immunohistochemical study
Authors: El‐Sharaby Ashraf , Ueda Katsura , Kurisu Kojiro , Wakisaka Satoshi 
Published: August 2002

AbstractPalatal taste buds are intriguing partners in the mediation of taste behavior and their spatial distribution is functionally important for suckling behavior, especially in the neonatal life. Their prenatal development has not been previously elucidated in the rat, and the onset of their maturation remains rather controversial. We delineated the development and frequency distribution of the taste buds as well as the immunohistochemical expression of α‐gustducin, a G protein closely related to the transduction of taste stimuli, in the nasoincisor papilla (NIP) and soft palate (SP) from the embryonic day 17 (E17) till the postnatal day 70 (PN70). The main findings in the present study were the development of a substantial number of taste pores in the SP of fetal rats (60.3 ± 1.7 out of 122.8 ± 5.5; mean ± SD/animal at E19) and NIP of neonatal rats (9.8 ± 1.0 out of 44.8 ± 2.2 at PN4). α‐gustducin‐like immunoreactivity (‐LI) was not expressed in the pored taste buds of either prenatal or newborn rats. The earliest expression of α‐gustducin‐LI was demonstrated at PN1 in the SP (1.5 ± 0.5 cells/taste bud; mean ± SD) and at PN4 in the NIP (1.4 ± 0.5). By age the total counts of pored taste buds continuously increased and their morphological features became quite discernible. They became pear in shape, characterized by distinct pores, long subporal space, and longitudinally oriented cells. Around the second week, a remarkable transient decrease in the total number of taste buds was recorded in the oral epithelium of NIP and SP, which might be correlated with the changes of ingestive behaviors. The total counts of cells showing α‐gustducin‐LI per taste bud gradually increased till the end of our investigation (14.1 ± 2.7 in NIP and 12.4 ± 2.5 in SP at PN70). We conclude that substantial development of taste buds began prenatally in the SP, whereas most developed entirely postnatal in the NIP. The present study provides evidence that the existence of a taste pore which is considered an important criterion for the morphological maturation of taste buds is not enough for the onset of the taste transduction, which necessitates also mature taste cells. Moreover, the earlier maturation of palatal taste buds compared with the contiguous populations in the oral cavity evokes an evidence of their significant role in the transmission of gustatory information, especially in the early life of rat. Anat Rec 263:260–268, 2001. © 2001 Wiley‐Liss, Inc.
Stereological determination of the volume of the rat hemimandible tissues
Authors: Silva Miralva A.J. , Merzel José 
Published: August 2002

AbstractRodent incisors are useful models to study the development and behavior of dental and periodontal tissues. Some studies require three‐dimensional reconstructions of the tooth but none of the described methods yield actual volumetric data. Unlike the rat lower incisors the hemimandible can be easily isolated and its volume was determined by Cavalieri's geometrical principle. This method associated with point‐counting volumetry was used to calculate the volume of the structures found in that bone mainly those related to the lower incisor. For 172 g male rats the mean volume of the hemimandible was 182.7 mm3, statistically not different from 184.9 mm3 the mean volume of the same hemimandibles determined by Archimedes' principle. The coefficients of error (CE) of Cavalieri's estimates for the hemimandible, incisor as a whole (the tooth itself, odontogenic region and periodontium) and bone tissue were less than 0.04. For the incisor individual tissues the CEs were usually above 0.05, however their calculated volumes are probably not different from the actual ones. The data for incisors and their periodontal tissues and for bone, because of continuous growth of these structures, are meaningful only for rats of the same gender, strain and weight range. Anat Rec 263:255–259, 2001. © 2001 Wiley‐Liss, Inc.
Application of magnetic and spectrometry methods in the detection of human activity in soils: a case study at the archaeological site of Kitros (Northern Greece)
Authors: Aidona E. V. , Sarris A. , Kondopoulou D. , Sanakis I. 
Published: August 2002

AbstractIn the present study the archaeological site of (Louloudies–Kitros) (northern Greece) is investigated by the use of magnetic and spectrometry geophysical methods. Soil samples were collected from several trenches within the archaeological site, as well as from radial traverses around kilns, which were used for glass production. Moreover, samples were collected from a long traverse, starting from the middle of the archaeological site and extending outside the site, in order to identify the limits of the settlement.Measurements were successful in identifying the different occupation levels and the boundaries of the archaeological site. High values of magnetic susceptibility and iron oxide content correlated well with the periods of intense human activity. Around the kilns, the mean values of the magnetic susceptibility indicated the effect of the fire mechanism in the surrounding area and gave some first evidence concerning the use of the kilns. Comparison of the magnetic and chemical properties of the anthropogenic soils suggests that their enhancement may be used as an index for locating areas and features of archaeological interest.Additionally, archaeomagnetic data have been obtained from a pottery and a glass kiln of the site. The magnetic directions (D = 355°, I = 62°, a95 = 3.6 and D = 356°, I = 51°, a95 = 2.3) were correlated to the reference curves compiled for Bulgaria and showed a satisfactory consistency for the declination, but the inclination values of the recorded magnetic field were divergent by about 10°. Copyright © 2001 John Wiley & Sons, Ltd.
Magnesium abnormalities of skeletal muscle in dermatomyositis and juvenile dermatomyositis
Authors: Niermann Kenneth J. , Olsen Nancy J. , Park Jane H. 
Published: August 2002

AbstractObjectiveTo characterize abnormalities in magnesium levels in the muscles of patients with dermatomyositis (DM) and juvenile dermatomyositis (JDM) and to evaluate the beneficial effects of prednisone and immunosuppressive therapy in elevating free magnesium (Mg2+) and ATP‐bound magnesium (Mg‐ATP).MethodsThe study groups consisted of 12 adult patients with DM and 10 juvenile patients with JDM. The 2 control groups were 11 normal adults and 6 healthy children. Levels of total ATP in the quadriceps muscles of the subjects were determined during rest, exercise, and recovery, using noninvasive P‐31 magnetic resonance spectroscopy (MRS). Concentrations of the biologically active free Mg2+ and the enzymatically active Mg‐ATP complex were determined from the spectroscopy data by calculation of the chemical shifts of the β‐phosphate peak of ATP.ResultsMg‐ATP levels in DM and JDM myopathic muscles were at least 37% lower than those in normal muscles during rest, exercise, and recovery from exercise (P < 0.0005). Free Mg2+ levels were normal in DM and JDM myopathic muscles at rest, but were significantly lower than control values during exercise and recovery (P < 0.029 and P < 0.005 for DM and JDM, respectively). Prednisone and immunosuppressive therapy partially reversed the magnesium abnormalities, as evidenced by elevation of the levels of Mg‐ATP and free Mg2+.ConclusionLow levels of Mg‐ATP and free Mg2+ are concordant with weakness and fatigue observed in DM and JDM patients. Immunosuppressive therapy alleviates, in part, the magnesium deficits in the diseased muscles. Therefore, Mg‐ATP and free Mg2+ may play a significant role in the pathophysiology of these diseases.