bluuebunny/crossref_metadata_2025_split huggingface dataset:
AFM and UFM surface characterization of rubber‐toughened poly(methyl methacrylate) samples
Authors: Porfyrakis K. , Kolosov O. V. , Assender H. E. 
Published: August 2002

AbstractThe microstructure of a series of injection‐molded and extruded rubber–toughened poly(methyl methacrylate) (RTPMMA) samples was investigated. Atomic force microscopy (AFM) and ultrasonic force microscopy (UFM) were used to study surface topography and local elastic properties. AFM topography measurements combined with UFM can reveal the distribution and orientation of the rubber particles in the PMMA matrix. UFM, in particular, reveals the core–shell structure of the particles as well as the presence of particles immediately under the surface, otherwise invisible. In some cases the particles appear to be covered by a thin PMMA layer, whereas in other cases they appear to have broken, thereby exposing parts of their internal structure. Generally, the particles are elongated in the skin region of the injection‐molded samples. On the other hand, the particles in the surface region of the extruded samples appear to be almost spherical. The observed difference is attributed to the fountain flow phenomenon, which takes place during injection molding. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2790–2798, 2001
Polypropylene fibers grafted with poly(acrylic acid)
Authors: Buchenska Jadwiga 
Published: August 2002

AbstractAn effective method for the grafting of poly(acrylic acid) on polypropylene fibers has been developed, using diphenyl and a dispersing agent (NNO) in the grafting bath as additives to facilitate the grafting process. The method makes it possible to obtain high grafting degrees of poly(acrylic acid) on polypropylene fibers with a minimal quantity of homopolymer as a side product. The effect of grafting degree on the moisture absorption and swelling of the modified fibers has been examined and described with mathematical equations. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2295–2299, 2002
Mechanical properties and morphologies of PP/mPE/filler composites
Authors: Qiu Gui‐Xue , Raue Frank , Ehrenstein Gottfried W. 
Published: August 2002

AbstractBecause of the poor impact behavior of polypropylene (PP) at low temperatures, the blending of PP with metallocene‐polymerized polyethylene (mPE) elastomers was investigated in this study. However, a reduced modulus of the overall blend was inevitable because of the addition to elastomers. To obtain a balance of the properties, we introduced rigid inorganic fillers to PP/mPE blends. The performance of the composites was characterized with tensile and Charpy notched impact tests, and the fracture morphology was examined with scanning electron microscopy. The results showed that the effects of fillers in a brittle matrix and in a ductile matrix were quantitatively different. For PP/mPE/filler ternary composites, the dependence of Young's modulus and yield strength on CaCO3 content was not significant compared with that of PP/filler binary composites, whereas the elongation at break and tensile toughness at room temperature for PP/mPE/filler systems were more improved. The impact strength of the PP/mPE blends filled with untreated glass beads and CaCO3 at a low temperature was lowered because of the weak interfacial bond. However, the values of the impact strength of the PP/mPE/filler composites at a low temperature remained at a high level compared with that of pure PP. In particular, a PP/mPE blend filled with surface‐treated kaolin had a higher low‐temperature impact toughness than the unfilled blend. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3029–3035, 2002; DOI 10.1002/app.2333
A co‐operative training programme in the field of coastal and ocean management
Authors: Vallejo Stella Maris 
Published: August 2002

Abstract1. One of the major challenges that countries and institutions will face in the years to come is the massive training of personnel in the broad spectrum of disciplines and cross‐sectoral perspectives needed to successfully implement integrated coastal zone management (ICZM) initiatives.2. This paper discusses the needs and challenges faced by institutions involved in training.3. In particular, the TRAIN–SEA–COAST Programme is discussed as an existing mechanism that provides an effective support system for training, with the focus on institution building at the national and regional levels, and increased cost‐effectiveness. Copyright © 2001 John Wiley & Sons, Ltd.
Correlation between the sequential ingrowth of afferents and transient patterns of cortical lamination in preterm infants
Authors: Kostović Ivica , Judaš Miloš 
Published: August 2002

AbstractTransient patterns of regional, laminar, modular, neuronal, and functional organization are essential features of the developing cerebral cortex in preterm infants. Analysis of cytological, histological, histochemical, functional, and behavioral parameters revealed that transient cerebral patterns develop and change rapidly between 24 weeks post ovulation (W) and birth. The major afferent fibers (thalamocortical, basal forebrain, and corticocortical) grow through the transient “waiting” subplate zone (SP) compartment and accumulate below the cortical plate (CP) between 22 and 26 W. These afferent fibers gradually penetrate the CP after 26 W. The prolonged process of dissolution of the SP can be explained by prolonged growth and maturation of associative connections in the human cerebral cortex. The neurons and circuitry elements of the transient layers are the substrate for transient functional and behavioral patterns. The predominance of deep synapses and deep dendritic maturation underlies the immaturity and different polarity of the cortical electrical response in the preterm infant. The significant changes in the transient SP, together with profound changes in the transient architecture of the neocortical plate, parallel the changes observed in recent MRI studies. The role of the SP in the formation of cortical connections and functions is an important factor in considering the pathogenesis of cognitive deficits after brain lesions in the preterm infant. Anat Rec 267:1–6, 2002. © 2002 Wiley‐Liss, Inc.
Induction of microsomal cytochrome P450s by tire‐leachate compounds, habitat components of Aedes albopictus mosquito larvae
Authors: Suwanchaichinda Chansak , Brattsten Lena B. 
Published: August 2002

AbstractBenzothiazole (BZT) and its derivatives are the major leachate compounds of automobile tires, the principal breeding habitat of Aedes albopictus, particularly in the United States. Effects of the compounds on insecticide toxicity, and activities and expression of microsomal cytochrome P450s (P450s) in the mosquito larvae were examined. Mosquito larvae were more tolerant to carbaryl, rotenone, and temephos when they were pre‐exposed to tire‐leachate compounds, particularly BZT. There was no change in toxicity from the aldrin treatment by BZT. The effect of BZT was reversed when a P450 inhibitor, piperonyl butoxide, was applied in admixture with the insecticides. Microsomes from BZT‐treated larvae had increased peroxidation activity of tetramethylbenzidine. This correlated with increased intensity of SDS‐PAGE protein bands corresponding to molecular weights of 59 and 62 kD, which were detected as heme‐containing proteins, a characteristic of P450s. The results suggest that BZT induces P450s, which detoxify insecticides and thus cause insecticide tolerance in the mosquito larvae. Arch. Insect Biochem. Physiol. 49:71–79, 2002. © 2002 Wiley‐Liss, Inc.
Th2‐oriented profile of male offspring T cells present in women with systemic sclerosis and reactive with maternal major histocompatibility complex antigens
Authors: Scaletti Cristina , Vultaggio Alessandra , Bonifacio Stefania , Emmi Lorenzo , Torricelli Francesca , Maggi Enrico , Romagnani Sergio , Piccinni Marie‐Pierre 
Published: August 2002

AbstractObjectiveTo characterize the cytokine production profile of male‐offspring T cells reactive against maternal major histocompatibility complex (MHC) antigens present in the peripheral blood and/or skin from women with systemic sclerosis (SSc).MethodsT cell clones were generated from peripheral blood and/or skin biopsy specimens from 3 women with SSc of recent onset and from peripheral blood from 3 healthy women, all of whom had 1 male child. All clones were screened for their proliferative response in vitro to maternal MHC antigens by measuring3H‐thymidine uptake and for their expression of Y chromosome by using fluorescence in situ hybridization. The concentrations of interferon‐γ and interleukin‐4 (IL‐4) released by T cell clones in response to maternal MHC antigens were evaluated in culture supernatants, using appropriate enzyme‐linked immunosorbent assays.ResultsThirty‐nine of 202 T cell clones generated from women with SSc and 11 of 312 from healthy women proliferated in vitro in response to maternal MHC antigens. Seven MHC‐reactive T cell clones obtained from women with SSc and 1 obtained from healthy women exhibited the Y chromosome, thus indicating that the clones were derived from T cells of male offspring. All clones generated from male‐offspring T cells of SSc women (but not from those of healthy women) produced significantly higher levels of IL‐4 in response to stimulation with maternal MHC antigens than did all other clones generated from the same women. The other clones proliferated in response to maternal or allogeneic MHC antigens but did not exhibit the Y chromosome.ConclusionMale‐offspring T cells that are present in the blood and skin of women with SSc and react with maternal MHC antigens exhibit a Th2‐oriented profile, supporting the possibility that a chronic graft‐versus‐host reaction attributable to long‐term microchimerism plays a pathogenic role in SSc.
Descriptions of joint pain by American Indians: Comparison of inflammatory and noninflammatory arthritis
Authors: Kramer B. Josea , Harker Judith O. , Wong Andrew L. 
Published: August 2002

AbstractObjectiveTo improve assessment of arthritis joint pain in American Indians by describing how symptoms are communicated.MethodIn‐depth interviews were conducted with American Indians who experience chronic joint pain (n = 56), to elicit descriptions and self‐reported ratings of pain, disability, and beliefs associated with the pain for affected joints (n = 326).ResultsDiscrete sets of specific verbal descriptions distinguished inflammatory arthritis (n = 20 terms) from noninflammatory arthritis (n = 22 terms), and indicated levels of pain intensity. An additional set of 14 vague but commonly used verbal descriptors did not distinguish the type of joint disease or pain intensity.ConclusionsSubtle pain complaints and vague verbal descriptions, such as “ache,” “hurt,” and “discomfort,” may reflect severe pain symptoms, disability, and more serious joint disease in American Indian patients. In addition, certain specific sensory descriptions used by American Indians suggest inflammatory arthritis and may warrant further evaluation.
Extended exposure of adult and fetal mice to 50 Hz magnetic field does not increase the incidence of micronuclei in erythrocytes
Authors: Abramsson‐Zetterberg L. , Grawé J. 
Published: August 2002

AbstractThe flow cytometer‐based micronucleus assay was used to study the effects on chromosomes in erythroid cells of CBA/Ca mice after extended exposure to 50 Hz magnetic field (MF), 14 μT, peak‐to‐peak (p‐p). The study included two different experiments: (a) mice exposed in utero during 18 days of their prenatal stage, and (b) adult mice exposed for 18 days. In experiment (a) 35 days after exposure was terminated, peripheral blood was drawn from the mice exposed in utero to determine whether the exposure had a genotoxic effect on the pluripotent erythroid stem cells. About 200000 polychromatic erythrocytes (PCE) and 200000 normochromatic erythrocytes (NCE) were analysed from each of 20 exposed mice. The EMF exposure did not significantly change the frequency of micronucleated PCE or NCE in comparison with 20 sham‐irradiated mice. There was no difference in the proportion of PCE between exposed and unexposed animals. Similarly, in experiment (b) no differences were seen between EMF exposed and unexposed adult mice when samples of peripheral blood were taken at the end of exposure and analyzed for micronuclei in PCE and NCE. The proportion of PCE was the same in both groups. The results indicate that exposure to EMF does not induce direct or indirect effects on chromosomes in erythroid cells expressed as increased levels of micronucleated erythrocytes of mice. No indications of delayed genetic effects were found. Bioelectromagnetics 22:351–357, 2001. © 2001 Wiley‐Liss, Inc.
Coordination of cell proliferation and cell fate decisions in the angiosperm shoot apical meristem†
Authors: Fletcher Jennifer C. 
Published: August 2002

AbstractA unique feature of flowering plants is their ability to produce organs continuously, for hundreds of years in some species, from actively growing tips called apical meristems. All plants possess at least one form of apical meristem, whose cells are functionally analogous to animal stem cells because they can generate specialized organs and tissues. The shoot apical meristem of angiosperm plants acts as a continuous source of pluripotent stem cells, whose descendents become incorporated into organ primordia and acquire different fates. Recent studies are unveiling some of the molecular pathways that specify stem cell fate in the center of the shoot apical meristem, that confer organ founder cell fate on the periphery, and that connect meristem patterning elements with events at the cellular level. The results are providing important insights into the mechanisms through which shoot apical meristems integrate cell fate decisions with cellular proliferation and global regulation of growth and development. BioEssays 24:27–37, 2002. Published 2002 John Wiley & Sons, Inc.
Animal models of Parkinson's disease
Authors: Betarbet Ranjita , Sherer Todd B. , Greenamyre J. Timothy 
Published: August 2002

AbstractAnimal models are important tools in experimental medical science to better understand pathogenesis of human diseases. Once developed, these models can be exploited to test therapeutic approaches for treating functional disturbances observed in the disease of interest. On the basis of experimental and clinical findings, Parkinson's disease (PD) was the first neurological disease to be modeled and, subsequently, to be treated by neurotransmitter replacement therapy. Agents that selectively disrupt or destroy catecholaminergic systems, such as reserpine, methamphetamine, 6‐hydroxydopamine and 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine have been used to develop PD models. Recently, it has been found that agricultural chemicals, such as rotenone and paraquat, when administered systemically, can reproduce specific features of PD in rodents, apparently via oxidative damage. Transgenic animals that over‐express α‐synuclein are used to study the role of this protein in dopaminergic degeneration. This review critically discusses animal models of PD and compares them with characteristics of the human disease. BioEssays 24:308–318, 2002. ©2002 Wiley Periodicals, Inc.
The efficacy of noncontingent reinforcement as treatment for automatically reinforced stereotypy
Authors: Britton Lisa N. , Carr James E. , Landaburu Heidi J. , Romick Kimberlee S. 
Published: August 2002

AbstractNoncontingent reinforcement (NCR), in the form of continuous access to preferred leisure items, has recently been reported as a successful treatment for automatically reinforced aberrant behavior. However, previous research has shown that the outcome of such procedures can be compromised under certain circumstances, such as when the response effort required to access leisure items is increased. The purpose of the current study was to assess the efficacy of two variations of NCR as treatment for automatically reinforced stereotypy. In the first phase of the study, functional analyses revealed that the stereotypy of three individuals with developmental disabilities was maintained independent of social consequences. A sensory class assessment was then conducted to identify the specific sensory products that appeared to maintain the behaviors. Finally, we evaluated the effects of NCR (using stimuli identified in the previous assessments) under two conditions. In the first condition, the leisure item was made freely available, by placing it on the table in front of the participant. In the other condition, an experimenter prompted the participant to interact with the leisure item at the beginning of the session. The results indicated that NCR successfully competed with stereotypy only when participants were prompted to interact with the leisure item. These findings are discussed in the context of developing NCR interventions for automatically reinforced aberrant behavior. Copyright © 2002 John Wiley & Sons, Ltd.
The reliability of the Detailed Behavior Report (DBR) in documenting functional assessment observations
Authors: Groden Gerald , Lantz Stephen 
Published: August 2002

AbstractAn emphasis on behavioral analysis, including delineation of antecedent conditions, has characterized the work of a rather large group of researchers and clinicians in recent years. Observational, or descriptive analysis, is now widely carried out, and instruments have been developed to facilitate such analysis. In spite of frequency of use in the clinic and laboratory, and as reported in journals, there is little data on the reliability of these measures. This study reports on the reliability of the Detailed Behavior Report (DBR), one instrument currently in use for conducting observational functional assessment. Copyright © 2001 John Wiley & Sons, Ltd.
Direct enzymatic reduction of lucigenin decreases lucigenin‐amplified chemiluminescence produced by superoxide ion
Authors: Afanas'ev Igor B. , Ostrakhovitch Elena A. , Mikhal'chik Elena V. , Korkina Ludmila G. 
Published: August 2002

AbstractThe interaction of superoxide ion with lucigenin produces chemiluminescence (CL), which is widely used for the detection of this radical anion. However, in many biological systems lucigenin may be directly reduced to its semiquinone by some enzymes. We found that if the direct reduction of lucigenin takes place, it decreases superoxide production due to the competition with one‐electron reduction of dioxygen to superoxide ion. Comparison of two methods of superoxide detection (lucigenin‐amplified CL and cytochrome c reduction) showed that there are excellent correlations between the results obtained by the two methods. Hence, lucigenin‐amplified CL remains a sensitive and reliable assay of superoxide detection. Copyright © 2001 John Wiley & Sons, Ltd.
Optical properties of ovalbumin in 0.130–2.50 μm spectral region
Authors: Arakawa E. T. , Tuminello P. S. , Khare B. N. , Milham M. E. 
Published: August 2002

AbstractIn our continuing series of measurements of the complex index of refraction for representative samples of biological materials, we measured ovalbumin (egg albumin) over the spectral region from 0.130 (76,923 cm−1) to 2.50 μm (4000 cm−1). Films of ovalbumin suitable for optical analyses were prepared and measured in addition to solutions of ovalbumin in water. We show several examples of how the methods used in this study produced accurate results for this complex and difficult to measure material. The present work is applicable to quantitative optical studies involving ovalbumin and other serpin proteins, as well as the study of proteinaceous toxins. © 2001 John Wiley & Sons, Inc. Biopolymers (Biospectroscopy) 62: 122–128, 2001
Vibrational CD (VCD) and atomic force microscopy (AFM) study of DNA interaction with Cr3+ ions: VCD and AFM evidence of DNA condensation
Authors: Andrushchenko Valery , Leonenko Zoya , Cramb David , van de Sande Hans , Wieser Hal 
Published: August 2002

AbstractThe interaction of natural calf thymus DNA with Cr3+ ions was studied at room temperature by means of vibrational CD (VCD) and infrared absorption (ir) spectroscopy, and atomic force microscopy (AFM). Cr3+ ion binding mainly to N7 (G) and to phosphate groups was demonstrated. ψ‐Type VCD spectra resembling electronic CD (ECD) spectra, which appear during ψ‐type DNA condensation, were observed. These spectra are characterized mainly by an anomalous, severalfold increase of VCD intensity. Such anomalous VCD spectra were assigned to DNA condensation with formation of large and dense particles of a size comparable to the wavelength of the probing ir beam and possessing large‐scale helicity. Atomic force microscopy confirmed DNA condensation by Cr3+ ions and the formation of tight DNA particles responsible for the ψ‐type VCD spectra. Upon increasing the Cr3+ ion concentration the shape of the condensates changed from loose flower‐like structures to highly packed dense spheres. No DNA denaturation was seen even at the highest concentration of Cr3+ ions studied. The secondary structure of DNA remained in a B‐form before and after the condensation. VCD and ir as well as AFM proved to be an effective combination for investigating DNA condensation. In addition to the ability of VCD to determine DNA condensation, VCD and ir can in the same experiment provide unambiguous information about the secondary structure of DNA contained in the condensed particles. © 2002 Wiley Periodicals, Inc. Biopolymers 61: 243–260, 2002
Combinatorial array‐based enzymatic polyester synthesis
Authors: Kim Dae‐Yun , Dordick Jonathan S. 
Published: August 2002

AbstractA combinatorial strategy for biocatalytic polymer synthesis is demonstrated. A library of polymers was synthesized in 96 deep‐well plates using AA‐BB polycondensations of acyl donors and acceptors. The library was based on four straight‐chain diesters as acyl donors (C3–C10) with aliphatic/aromatic diols as well as more diverse structures including carbohydrates, nucleic acids, and a natural steroid diol used as acyl acceptors. The lipase from Candida antarctica was active in acetonitrile and was capable of catalyzing the polycondensation of the aforementioned monomers to polymers with Mw's reaching as high as 20,000 Da, including the preparation of novel sugar‐containing polyesters. The combinatorial approach to biocatalytic polymer synthesis described herein serves as a foundation for polymeric materials discovery by demonstrating that polymer arrays can be produced from structurally complex monomers. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 76: 200–206, 2001.