bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of amphiphilic PS‐b‐PMAA diblock copolymer by means of atom transfer radical polymerization
Authors: Wang Guojian , Yan Deyue 
Published: August 2002

AbstractAmphiphilic diblock copolymers of polystyrene‐b‐poly(methacrylic acid) were synthesized by means of atom transfer radical polymerization. First, the polystyrene with a bromine atom at the chain end (PS‐Br) was prepared using styrene as the monomer, 1‐bromoethyl benzene as the initiator, and CuCl/2,2′‐bipyridyl (bpy) as the catalyst ([1‐bromoethyl benzene]/[CuCl]/[bpy] = 1:1:3). The polymerization was well controlled. Second, the diblock copolymer of polystyrene‐b‐poly(tert‐butyl methacrylate) was synthesized also by atom transfer radical polymerization using PS‐Br as the macro‐initiator, CuCl/bpy as the catalyst, and tert‐butyl methacrylate (tBMA) as the monomer. Finally, the amphiphilic diblock copolymer, PS‐b‐PMAA, was obtained by hydrolysis of PS‐b‐PtBMA under the acid condition. The molecular weight and the structure of aforementioned copolymers were characterized with gel permeation chromatography, infrared, and nuclear magnetic resonance. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2381–2386, 2001
SEM study of a polystyrene/clay nanocomposite
Authors: Fan Jiaqi , Liu Suhuai , Chen Guangming , Qi Zongneng 
Published: August 2002

AbstractWe carried out a scanning electron microscopy study to investigate the morphology of a polystyrene (PS)/montmorillonite nanocomposite. Monodispersed spherical particles, about 200 nm in diameter, were observed when PS/montmorillonite powder was dispersed in water, whereas planar silicate sheets were found for cetyltrimethylammonium bromide‐exchange montmorillonite. The fracture surface of a PS/clay nanocomposite pellet sample showed a lot of fibrils rather than the smooth surface of a pure PS pellet. After the PS/clay nanocomposite pellet was chemically etched, flaky montmorillonite particles were homogeneously dispersed in the PS matrix. A film sample, prepared by the pressing of the PS/clay nanocomposite melt, revealed that the montmorillonite primary particles oriented parallel to the surface, and the corresponding X‐ray diffraction distribution map of silicon atoms confirmed that the dispersed particles were montmorillonite primary particles. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 66–69, 2002
Interpolyelectrolyte complex of poly(2‐vinylpyridinium chloride) and poly(sodium phosphate)
Authors: Acar Nermin 
Published: August 2002

AbstractA polyelectrolyte complex (PEC) was formed by mixing aqueous solutions of the polyanion poly(sodium phosphate) with the polycation poly(2‐vinylpyridinium chloride). Conductometric and potentiometric titrations indicated the electrochemical end point of each titration. In all cases the end point occurred at a unit molar ratio of polyanionic to polycationic groups that was approximately one. The stoichiometry was also confirmed by analysis of the supernatant liquid in conjunction with the weights of the initial components and complex. An analysis showed that the starting materials were regenerated after dissolution of the complex with a 2M HCl solution. The interaction of the bivalent cupric ions with PEC were also investigated. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3022–3028, 2002; DOI 10.1002/app.2332
Mechanical and thermal properties of acrylic fibers crosslinked with disulfonyl azides
Authors: Baker D. A. , East G. C. , Mukhopadhyay S. K. 
Published: August 2002

AbstractA novel method for the crosslinking of acrylic fibers was devised, which uses disulfonyl azides as crosslinking agents. This is a fiber‐finishing process in which 1,6‐hexanedisulfonyl azide, 1,3‐benzenedisulfonyl azide, 4,4‐biphenyldisulfonyl azide, 1,5‐naphthalenedisulfonyl azide, and 2,6‐naphthalenedisulfonyl azide were applied to an acrylic fiber (Courtelle) and thermally treated to bring about crosslinking. A study was made of the mechanical and thermal properties of the crosslinked fibers and of the abrasion and pilling performance of the associated fabrics. Crosslinking brought about significant improvements in the initial modulus, resistance to abrasion, pilling performance, and thermal stability of the fibers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1309–1319, 2002; DOI 10.1002/app.2349
Changes in population parameters and behaviour of blue cod (Parapercis colias; Pinguipedidae) in Long Island—Kokomohua Marine Reserve, Marlborough Sounds, New Zealand
Authors: Davidson R.J. 
Published: August 2002

Abstract
With the establishment of the 619‐ha Long Island—Kokomohua Marine Reserve in April 1993, a biological monitoring programme designed to investigate changes due to the total no‐take legislation applied to the reserve was initiated.
Size, distribution and behaviour of blue cod (Parapercis colias; Pinguipedidae) were investigated using baited hooks at reserve and control rubble bottom habitats annually from 1993 to 2000. Blue cod abundance was estimated using visual diver strip transects annually for a period of 9 years from 1992 to 2001.
A total of 5628 blue cod (2436 reserve and 3192 control specimens) were captured, measured and released. Two years after the reserve was established, the average size of blue cod was 22.4 mm larger inside the reserve compared with control sites outside it.
Over the duration of the study, the mean length of blue cod captured using baited hooks increased in the no‐take reserve, but declined at the control sites. By the end of the study, in April 2000, the proportion of large blue cod >330 mm in length in the reserve was 35% compared with <1% at the control sites, where recreational fishing activities occurred.
Blue cod catch rates from experimental fishing in the reserve increased within 11 months of removal of recreational fishing activities and continued to increase up to 47 months, in contrast to the control areas where recreational fishing was permitted, catch rates remained consistently low. Increased catch rates in the reserve were not due to increased blue cod abundance, rather an increase in the proportion of naïve fish in the population.
From March 1998 to the end of the study, the density of blue cod in the reserve was significantly higher compared with the control sites. This increase was primarily due to an increase in the density of larger blue cod >300 mm length in the reserve and a corresponding small decline in the density of these larger fish at the control sites.
It is concluded that the cessation of recreational fishing in the reserve had resulted in an increase in blue cod size, catch rate and abundance and also in a change to blue cod behaviour.
Copyright © 2001 John Wiley & Sons, Ltd.
Cellular origin of endochondral ossification from grafted periosteum
Authors: Ueno Takaaki , Kagawa Toshimasa , Mizukawa Nobuyoshi , Nakamura Hiroaki , Sugahara Toshio , Yamamoto Toshio 
Published: August 2002

AbstractGrafted periosteum is known to have potential for heterotopic bone formation by endochondral ossification. Although osteochondrogenic cells have been thought to originate from the osteogenic layer in grafted periosteum, no histological report has yet demonstrated this. The present study was designed to elucidate the origin of chondrogenesis preceding bone formation in grafted periosteum. Periostea harvested from young Japanese white rabbits' tibiae were grafted into suprahyoid muscles and examined radiographically and histologically at postoperative days 1, 7, 9, 14, 21, and 35. Normal periostea and tibial graft site were also examined. Surgical harvesting of the periosteum split and damaged its osteogenic layer but retained the fibrous layer intact. Most of the osteoblasts remained on the tibial bone surface, and only few cells of the osteogenic layer were present in grafted tissue. By the seventh day after grafting, the fibrous layer had thickened. The fibroblastic cells in the fibrous layer had significantly increased in number (P < 0.01) and were positively stained for proliferating cell nuclear antigen. These cells exhibited alkaline phosphatase activity at day 9. The differentiated chondrocytes had formed cartilage at postoperative day 14. Cells in the osteogenic layer appeared necrotic and subsequently disappeared. Following postoperative day 21, cartilage was replaced by trabecular bone. Bone formation was completed by 35 days. An X‐ray analysis at this time also revealed new bone formation. These findings indicate that grafted periosteum forms bone by endochondral ossification and that the cells of the fibrous layer play essential roles in chondrogenesis that precedes such bone formation. Anat Rec 264:348–357, 2001. © 2001 Wiley‐Liss, Inc.
GABA‐, glycine‐, and glutamate‐immunoreactive bouton profiles in apposition to neurons of the central cervical nucleus in the rat
Authors: Ragnarson Birger , Yi Seong Joon , Ulfhake Brun , Grant Gunnar 
Published: August 2002

AbstractThe neurons of the central cervical nucleus (CCN) convey information about the position and movements of the head, and receive excitatory input from dorsal neck muscles and the labyrinth. Both of these afferent sources form glutamatergic synaptic contacts with CCN neurons. However, these sensory afferent sources can also inhibit CCN neurons. To further elucidate the synaptic organization, we made an electron microscopic investigation, identifying and evaluating the relative frequency of bouton profiles containing the inhibitory transmitters GABA and glycine in apposition to identified CCN neurons. In addition, labeling for glutamate was performed. The identification of the CCN neurons was made possible by injections of retrograde tracer substances into the cerebellum. These substances were made visible by preembedding immunocytochemistry or postembedding immunogold staining. Such staining was also used to detect the three amino acids that were found in boutons apposed to the identified neurons (cf. Örnung et al., J. Comp. Neurol. 1996;365:413–426; Lindå et al., J. Comp. Neurol. 2000;425:10–23). Due to the relatively poor transport of the tracer substances into dendrites of the CCN neurons, the analysis was restricted to the cell body and included bouton profiles in direct apposition to the soma membrane. Data from 10 CCN neurons revealed that about 50% of the apposing bouton profiles were immunoreactive for GABA, and about 34% for glycine. In four neurons, the degree of colocalization of GABA and glycine was determined to be close to 30%. Thus, the vast majority of glycine‐labeled profiles also contained GABA, while a considerable fraction of the profiles were immunoreactive for only GABA. The values for glycine immunoreactive bouton profiles presented here may represent somewhat low estimates, depending on the method used. Data from four neurons showed that about 18% of the profiles were labeled for glutamate. The large fraction of purely GABA immunoreactive profiles, or at least a substantial group of them, is suggestive of their derivation from axons descending from the brainstem. Anat Rec 266:226–233, 2002. © 2002 Wiley‐Liss, Inc.
Horizontally oriented clusters of multiple chondrons in the superficial zone of ankle, but not knee articular cartilage
Authors: Schumacher Barbara L. , Su Jui‐Lan , Lindley Kathy M. , Kuettner Klaus E. , Cole Ada A. 
Published: August 2002

AbstractOsteoarthritis is a progressive disease that is initiated at the surface of articular cartilage and proceeds to destroy the entire depth of the cartilage. The prevalence of osteoarthritis varies in different joints; e.g., the ankle joint has a very low prevalence of the disease compared to the knee joint. To better understand any inherent differences between the articular cartilage of the ankle and that of the knee that would account for the difference in occurrence of osteoarthritis, studies were undertaken to examine differences between the superficial zones in these two joint cartilages obtained from human donors. Chondrocytes in the superficial zones of the normal ankle (talocrural) and the normal knee (tibiofemoral) joints were identified with a monoclonal antibody specific for the superficial zone protein (SZP). When the chondrocytes from both joints were compared in serial horizontal sections, the chondrocytes in the superficial zone of the knee cartilage were seen either as isolated single cells or as doublets. However, the chondrocytes within the superficial zone of normal ankle cartilage were arranged in planar clusters containing multiple chondrons composed of 2–13 cells. There were no detectable differences in the chondrocyte clusters in the superficial zone of the ankle with respect to age, gender, or site on the cartilage surface. Adjacent to a lesion in an ankle joint with degenerative changes, the clusters were larger, containing up to 22 chondrocytes. This is the first report documenting the presence of multiple chondrons in the superficial zone of normal human adult articular cartilage. Anat Rec 266:241–248, 2002. © 2002 Wiley‐Liss, Inc.
Prenatal development of the human mandible
Authors: Lee Suk Keun , Kim Yeon Sook , Oh Hee Soo , Yang Kyu Ho , Kim Eun Cheol , Chi Je Geun 
Published: August 2002

AbstractIn an effort to better understand the interrelationship of the growth and development pattern of the mandible and condyle, a sequential growth pattern of human mandibles in 38 embryos and 111 fetuses were examined by serial histological sections and soft X‐ray views. The basic growth pattern of the mandibular body and condyle appeared in week 7 of fertilization. Histologically, the embryonal mandible originated from primary intramembranous ossification in the fibrous mesenchymal tissue around the Meckel cartilage. From this initial ossification, the ramifying trabecular bones developed forward, backward and upward, to form the symphysis, mandibular body, and coronoid process, respectively. We named this initial ossification site of embryonal mandible as the mandibular primary growth center (MdPGC). During week 8 of fertilization, the trabecular bone of the mandibular body grew rapidly to form muscular attachments to the masseter, temporalis, and pterygoid muscles. The mandible was then rapidly separated from the Meckel cartilage and formed a condyle blastema at the posterior end of linear mandibular trabeculae. The condyle blastema, attached to the upper part of pterygoid muscle, grew backward and upward and concurrent endochondral ossification resulted in the formation of the condyle. From week 14 of fertilization, the growth of conical structure of condyle became apparent on histological and radiological examinations. The mandibular body showed a conspicuous radiating trabecular growth pattern centered at the MdPGC, located around the apical area of deciduous first molar. The condyle growth showed characteristic conical structure and abundant hematopoietic tissue in the marrow. The growth of the proximal end of condyle was also approximated to the MdPGC on radiograms. Taken together, we hypothesized that the MdPGC has an important morphogenetic affect for the development of the human mandible, providing a growth center for the trabecular bone of mandibular body and also indicating the initial growth of endochondral ossification of the condyle. Anat Rec 263:314–325, 2001. © 2001 Wiley‐Liss, Inc.
Molecular structure of the peritrophic membrane (PM): Identification of potential PM target sites for insect control
Authors: Wang Ping , Granados Robert R. 
Published: August 2002

AbstractPeritrophic membranes (PMs) are an invertebrate‐unique structure that lines the digestive tract, playing important roles in facilitating food digestion and providing protection to the gut epithelium. The importance of PMs in insects has been recognized ever since its presence was identified 200 years ago. In the last 5 years, significant progress towards understanding the PM molecular structure and the mechanism for PM formation has been made. Recent studies on Type 1 PMs from lepidopteran larvae have suggested a model for the PM molecular structure and formation. The important physiological functions of the PM suggest that PMs can be a significant structural target for insect control and the current understanding of the structure of lepidopteran larval PMs has provided us with potential opportunities for targeting the PM by various mechanisms. Arch. Insect Biochem. Physiol. 47:110–118, 2001. © 2001 Wiley‐Liss, Inc.
Pharmacological characterization of STKR, an insect G protein‐coupled receptor for tachykinin‐like peptides
Authors: Torfs Herbert , Oonk Hendrica B. , Broeck Jozef Vanden , Poels Jeroen , Van Poyer Wendy , De Loof Arnold , Guerrero Felix , Meloen Robbert H. , Åkerman Karl , Nachman Ronald J. 
Published: August 2002

AbstractSTKR is a G protein–coupled receptor that was cloned from the stable fly, Stomoxys calcitrans. Multiple sequence comparisons show that the amino acid sequence of this insect receptor displays several features that are typical for tachykinin (or neurokinin, NK) receptors. Insect tachykinin‐related peptides, also referred to as “insectatachykinins,” produce dose‐dependent calcium responses in Drosophila melanogaster Schneider 2 cells, which are stably transfected with this receptor (S2‐STKR). These responses do not depend on the presence of extracellular Ca2+‐ions. A rapid agonist‐induced increase of inositol 1,4,5‐trisphosphate (IP3) is observed. This indicates that the agonist‐induced cytosolic Ca2+‐rise is caused by a release of Ca2+ ions from intracellular calcium stores. The pharmacology of STKR is analyzed by studying the effects of the most important antagonists for mammalian NK‐receptors on STKR‐expressing insect cells. The results show that spantide II, a potent substance P antagonist, is a real antagonist of insectatachykinins on STKR. We have also tested the activity of a variety of natural insectatachykinin analogs by microscopic image analysis of calcium responses in S2‐STKR cells. At a concentration of 1 μM, almost all natural analogs produce a significant calcium rise in stable S2‐STKR cells. Interestingly, Stc‐TK, an insectatachykinin that was recently discovered in the stable fly (S. calcitrans), also proved to be an STKR‐agonist. Stc‐TK, a potential physiological ligand for STKR, contains an Ala‐residue (or A) instead of a highly conserved Gly‐residue (or G). Arch. Insect Biochem. Physiol. 48:39–49, 2001. © 2001 Wiley‐Liss, Inc.
Increased prevalence of renal disease in systemic lupus erythematosus families with affected male relatives
Authors: Stein Catherine M. , Olson Jane M. , Gray‐McGuire Courtney , Bruner Gail R. , Harley John B. , Moser Kathy L. 
Published: August 2002

AbstractObjectiveTo distinguish familial differences from sex‐related differences in the clinical manifestations of systemic lupus erythematosus (SLE).MethodsA total of 372 affected individuals from 160 multiplex SLE pedigrees were analyzed. Twenty‐five of these pedigrees contained at least 1 affected male relative. Comparisons of the presence of each of the 11 1982 American College of Rheumatology criteria for SLE were made between female family members with affected male relatives and those without affected male relatives, using Fisher's exact tests.ResultsThe presence of renal disease was significantly increased in female family members with an affected male relative when compared with those with no affected male relative (68% and 43%, respectively; P = 0.002). This trend remained after stratifying by race and was most pronounced in European Americans. A familial basis for differences in hematologic and immunologic manifestations was also suggested, while arthritis and dermatologic features appeared to be most influenced by sex.ConclusiosOur results demonstrate that the increased prevalence of renal disease previously reported in men with SLE is, in large part, a familial rather than sex‐based difference, at least in multiplex SLE families. Distinguishing familial from sex‐related differences may facilitate efforts to understand the genetic and hormonal factors that underlie this complex autoimmune disease.
Genome scan for quantity of hand osteoarthritis: The Framingham study
Authors: Demissie S. , Cupples L. A. , Myers R. , Aliabadi P. , Levy D. , Felson D. T. 
Published: August 2002

AbstractObjectiveTo search for markers linked to quantity of radiographic hand osteoarthritis (OA) in the Framingham Heart Study.MethodsThe sample included 684 original cohort members and 793 offspring in 296 pedigrees. Radiographic OA features evaluated included the Kellgren/Lawrence (K/L) score, osteophytes, and joint space narrowing (0–3 scale). Four quantitative phenotypes were computed from these measurements: sum of K/L scores across hand joints, sum of osteophyte scores, sum of joint space narrowing scores, and proportion of affected joints. Prior to linkage analysis, these phenotypes were adjusted for age using a linear regression analysis from which standardized residuals were computed. The regression analysis was performed separately for each sex and each generation. The variance component model (SOLAR) was then applied to the normalized scores of the residuals.ResultsThe average age was 62 years for the original cohort and 54 years for the offspring. Fifty percent of the original cohort and 30% of their offspring had at least 1 affected joint (K/L score ≥2). Heritability ranged from 28% (proportion of joints affected with OA) to 34% (sum of K/L scores). Eight chromosomal regions indicated suggestive linkage (multipoint logarithm of odds [LOD] score >1.5) for at least 1 phenotype; LOD scores were highest for joint space narrowing, with a multipoint LOD score = 2.96 on chromosome 1p at D1S1665. Chromosomes 7, 9, 13, and 19 indicated consistent LOD score elevation for multiple OA phenotypes.ConclusionThere are several chromosomes that may harbor OA susceptibility genes. Further investigation of these regions using larger studies and finer maps will be important to confirm linkage.
Cognitive space and information space
Authors: Newby Gregory B. 
Published: August 2002

AbstractThis article works towards realization of exosomatic memory for information systems. In exosomatic memory systems, the information spaces of systems will be consistent with the cognitive spaces of their human users. A method for measuring concept relations in human cognitive space is presented: the paired comparison survey with Principal Components Analysis. A study to measure the cognitive spaces of 16 research participants is presented. Items measured include relations among seven TREC topic statements as well as 17 concepts from the topic statements. A method for automatically generating information spaces from document collections is presented that uses term cooccurrence, eigensystems analysis, and Principal Components Analysis. The extent of similarity between the cognitive spaces and the information spaces, which were derived independently from each other, is measured. A strong similarity between the information spaces and the cognitive spaces are found, indicating that the methods described may have good utility for working towards information systems that operate as exosomatic memories.