bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ancestral loss of the maxillary sinus in Old World monkeys and independent acquisition in Macaca
Authors: Rae Todd C. , Koppe Thomas , Spoor Fred , Benefit Brenda , McCrossin Monte 
Published: August 2002

AbstractCercopithecoid monkeys are unique among primates in that all species (except macaques) lack a maxillary sinus, an unusual condition among eutherian mammals. Although this uncommon distribution of cranial pneumatization was noted previously, the phylogenetic ramifications have not been investigated fully. Recently, character state optimization analysis of computed tomography (CT) data from extant Old World monkeys suggested that the loss of the sinus may have occurred at the origin of the group, unlike previous hypotheses positing only a reduction in size of the structure. To critically evaluate the “early loss” hypothesis, a recently recovered complete cranium of Victoriapithecus macinnesi from Maboko Island, Kenya, was examined by CT to determine the extent of its cranial pneumatization. This taxon is crucial for evaluating character state evolution in Old World monkeys, due to its phylogenetic position, preceding the cercopithecine/colobine split.CT analysis reveals only cancellous bone lateral of the nasal cavity, indicating that Victoriapithecus does not possess a maxillary sinus. Phylogenetic evaluation of the fossil with extant catarrhine taxa strongly supports the early loss of the sinus in cercopithecoids. The results suggest that the maxillary sinus found in the genus Macaca is not homologous with that of other eutherians, which may provide insights into the origin and function (if any) of the paranasal pneumatizations. Am J Phys Anthropol 117:293–296, 2002. © 2002 Wiley‐Liss, Inc.
Morphological variation within a macaque hybrid zone
Authors: Bynum Nora 
Published: August 2002

AbstractA hybrid zone exists between Macaca tonkeana and Macaca hecki (Primates: Cercopithecidae), centered along the Tawaeli‐Toboli road in the narrow isthmus that connects North and Central Sulawesi, Indonesia. The current study demonstrates morphological substructure from north to south across the hybrid zone. Macaques to the northwest of the Tawaeli‐Toboli road more closely resemble M. hecki, and macaques to the southeast of the road resemble M. tonkeana. While morphology shifted for both males and females over a distance of 1,500–2,000 m, adult males were significantly more M. tonkeana‐like across the morphological gradient. This suggests that in the study area, males of M. tonkeana‐like morphology are dispersing into hybrid groups at the expense of M. hecki‐like males. A permutation analysis of diagnostic character states indicated that associations existed among several morphological traits. This could be due to the operation of one or several nonexclusive evolutionary processes, including recent secondary contact, pleiotropic effects, physical linkage of loci, natural selection against hybrids, the influx of parental types, or assortative mating. Continued environmental perturbation associated with the Tawaeli‐Toboli road is likely to be a significant factor in the future of the M. tonkeana/M. hecki hybrid interaction. Am J Phys Anthropol 118:45–49, 2002. © 2002 Wiley‐Liss, Inc.
Loss of interhemispheric inhibition on the ipsilateral primary sensorimotor cortex in patients with brachial plexus injury: fMRI study
Authors: Hsieh Jen‐Chuen , Cheng Henrich , Hsieh Hsiu‐Min , Liao Kwong‐Kum , Wu Yu‐Te , Yeh Tzu‐Chen , Ho Low‐Tone 
Published: August 2002

AbstractThis functional magnetic resonance imaging study verified an antagonistic pattern in which a concomitant deactivation of ipsilateral primary sensorimotor (SM1) was coupled to the contralateral SM1 activation in healthy controls during unimanual hand grasping. Of note, dramatic reduction of ipsilateral SM1 deactivation (loss of antagonistic pattern) was observed during movement of intact hands by patients with unilateral brachial plexus injury. We propose that the disappearance of the antagonistic pattern of SM1 activities in the patients with brachial plexus injury reflects a reduction of interhemispheric inhibition, which may mirror an adaptive mechanism to functional status.
Mature, long‐lived CD4+ and CD8+ T cells are generated by the thymoma in myasthenia gravis
Authors: Buckley Camilla , Douek Daniel , Newsom‐Davis John , Vincent Angela , Willcox Nicholas 
Published: August 2002

AbstractAntibodies to muscle acetylcholine receptors, to other muscle antigens, and to some cytokines are found in the majority of patients with thymic tumors (thymomas) and myasthenia gravis (MG). The role of the tumor in initiating autoimmunity, however, is unclear; in particular, it is not known whether the thymoma exports mature and long‐lived T cells, which could provide help for antibody production in the periphery. Here, we quantified recently exported thymic T cells using the approach of measuring episomal DNA fragments [T‐cell receptor excision circles (TRECs)], generated by T‐cell receptor gene rearrangement. Compared to values in healthy individuals (n = 10) or in patients with late‐onset MG (n = 8), TREC levels were significantly raised in both the CD4+ and CD8+ peripheral blood compartments of patients with thymoma and MG (n = 14, p = 0.002 and p = 0.0004 compared to healthy controls) but only in the CD8+ compartment of the 3 patients with thymoma without MG (p = 0.4 and p = 0.01 for CD4+ and CD8+). TREC levels decreased following thymectomy to values similar to controls but were substantially raised in patients who had developed tumor recurrence (n = 6, p = 0.04 and p = 0.02 for CD4+ and CD8+); this was associated with increased antibodies to interferon‐α and interleukin‐12 in the one case studied serially. Collectively, these results support the hypothesis that the neoplastic thymoma tissue itself can generate and export mature, long‐lived T cells and that these T cells reflect the thymic pathology and are likely to be related to the associated autoimmune diseases. The results also provide a new approach for early diagnosis of thymoma recurrence.
Are certain diuretics also anticonvulsants?
Authors: Hesdorffer Dale C. , Stables James P. , Hauser W. Allen , Annegers John F. , Cascino Gregory 
Published: August 2002

AbstractA history of diuretic use has been shown to be protective for first unprovoked seizure in adult patients. Recent animal studies suggest that certain diuretics have anticonvulsant activity. We evaluated the potential for the anticonvulsant activity of current diuretic use in a population‐based, case–control study in older adults. We also tested chlorthiazide and furosemide for seizure protection in animal models of epilepsy. Concurrent medical prescription of any diuretic was protective for the development of epilepsy [odds ratio (OR) = 0.62, 95% confidence interval (CI) = 0.39–0.99]. A protective effect for current thiazide use was observed (OR = 0.53, CI = 0.31–0.90), and a protective effect for furosemide was suggested (OR = 0.44, CI = 0.1–1.9). In mice, both chlorthiazide and furosemide suppressed the occurrence of maximal electroshock‐induced seizures in a dose‐dependent manner. Chlorthiazide's toxic dose for 50% of animals tested (TD50) could not be achieved even with dosing as high as 1,500 mg/kg; for furosemide, TD50 was 549 mg/kg. Results were similar in rats. Furosemide and chlorthiazide are protective for unprovoked seizures in an epidemiological study and in animal models. Given the potential therapeutic value for seizure control, low toxicity, and low cost, therapeutic efficacy should be explored in clinical studies.
Myelinopathia centralis diffusa (vanishing white matter disease): Evidence of apoptotic oligodendrocyte degeneration in early lesion development
Authors: Brück Wolfgang , Herms Jochen , Brockmann Knut , Schulz‐Schaeffer Walter , Hanefeld Folker 
Published: August 2002

AbstractWe describe histopathological changes in a 2‐year‐old boy who died from myelinopathia centralis diffusa. Despite extensive white matter destruction, surprisingly high numbers of oligodendrocytes expressing proteolipid protein mRNA were detected. In an active demyelinating lesion in the brainstem, oligodendrocytes showed typical signs of apoptosis. We suggest that death of mature oligodendrocytes is the critical event in the disease.
Investigation of heterogeneous radical polymerization of methyl methacrylate with polydimethylsiloxane as stabilizing agent in supercritical CO2 by turbidimetry
Authors: Fehrenbacher U. , Ballauff M. , Muth O. , Hirth T. 
Published: August 2002

AbstractExperimental results of a turbidimetric in situ investigation of the heterogeneous radical polymerization (dispersion polymerization) of methyl methacrylate and polydimethylsiloxane–monomethacrylate in supercritical carbon dioxide are presented. The experiments were carried out at 60 °C and 330 bar. Turbidity spectra were measured directly in the autoclave to determine the average particle diameter στ and the particle density NAV/V during the first five minutes of polymerization. The results show that the particle density increased until a maximum was achieved, whereas the particle diameter increased during the first stage. Moreover, a comparison with kinetic data suggests that the particles nucleate through coagulation of polymer that is formed in the homogeneous phase. Copyright © 2001 John Wiley & Sons, Ltd.
Arsenic speciation in sea scallop gonads
Authors: Lai Vivian W.‐M. , Cullen William R. , Ray Sankar 
Published: August 2002

AbstractThe arsenic species in male and female sea scallop gonads (Placopecten magellanicus) at pre‐spawning and post‐spawning stages, collected near Newfoundland, Canada, were characterized by using high‐performance liquid chromatography–inductively coupled plasma‐mass spectrometry. All samples contain arsenobetaine (0.5–3.0 µg g−1) and a dimethylarsinoylriboside derivative as the major water‐soluble arsenic compounds. Male pre‐spawning gonads contain 0.35–2.4 µg g−1 of the dimethylarsinoylriboside. Female pre‐spawning gonads contain 0.47–9.64 µg g−1 of the same compound. Post‐spawning gonads, both male and female, contain higher concentrations of this compound (3.7–11.4 µg g−1). The total concentrations of water‐soluble arsenic compounds are different in male and female pre‐spawning gonads. These differences are not obvious in post‐spawning gonads. Post‐spawning gonads contain higher total concentrations of water‐soluble arsenic compounds than pre‐spawning gonads. Copyright © 2001 John Wiley & Sons, Ltd.
Computational study of dimethyl‐ and trimethyl‐tin(IV) complexes of porphyrin derivatives
Authors: Duca Dario , Barone Giampaolo , Manna Gianfranco La , Fiore Tiziana , Pellerito Claudia , Stefano Roberta Di , Scopelliti Michelangelo , Pellerito Lorenzo 
Published: August 2002

AbstractThe molecular geometry, energetics and electronic charge distribution of diorgano‐ and triorgano‐tin(IV) complexes of [protoporphyrin‐IX] and [meso‐tetra(4‐carboxyphenyl)porphine] derivatives were determined at semi‐empirical and ab initio levels. To study the molecular details of the complexes, simpler molecule models were calculated by the ab initio pseudo‐potential method. The molecular properties of these complexes are essentially independent of the presence of the peripheral tin atoms. Agreement was always found among the results of the different computational approaches, as well as between the theoretical and the experimental findings on the molecular geometry of the hypothesized complexes. Interaction modes between water and the organo‐tin systems considered were affected strongly by the presence of peripheral tin atoms. Copyright © 2001 John Wiley & Sons, Ltd.
Atmospheric pressure chemical vapour deposition of selenium and tellurium films by UV laser photolysis of diethyl selenium and diethyl tellurium
Authors: Pola Josef , Bastl Zdeněk , Šubrt Jan , Ouchi Akihiko 
Published: August 2002

AbstractExcimer laser‐induced photolysis of gaseous diethyl selenium and diethyl tellurium (C2H5)2M (M = Se, Te) is controlled by cleavage of both MC bonds, it yields C1–C4 hydrocarbons (ethene as major product) and results in chemical vapour deposition of selenium films and nanosized tellurium powder. The selenium and tellurium properties were characterized by X‐ray photoelectron spectroscopy and Scanning electron Microscopy techniques. Copyright © 2001 John Wiley & Sons, Ltd.
Organometallic dyes: Part 1. Synthesis of orange to cyan dyes based on donor–conjugated–acceptor chromogenes using ferrocene as the donor group
Authors: Asiri Abdullah Mohamed 
Published: August 2002

AbstractA novel series of organometallic donor–conjugated–acceptor dyes derived from ferrocene as the donor group have been synthesized via the Knoevenagel reaction of ferrocene carboxaldehyde and various active methylene compounds to give a range of dyes ranging from orange to blue–green in color. The most bathochromic dye is that derived from dialkyl thiobarbituric acid and the least is that derived from the tetralone. The dyes showed an unusual negative solvatochromism as the solvent polarity increased. All dyes synthesized are expected to have some non‐linear optical properties, as evidenced from the pronounced solvatochromism. Copyright © 2001 John Wiley & Sons, Ltd.
High‐resolution thermogravimetry of polyphenylene sulfide film under four atmospheres
Authors: Li Xin‐Gui , Huang Mei‐Rong , Bai He , Yang Yu‐Liang 
Published: August 2002

AbstractThermal degradation of polyphenylene sulfide (PPS) film was investigated in air, nitrogen, helium, and argon with different physical and reactive characteristics from room temperature to 790°C by a high‐resolution thermogravimetry (TG) at a variable heating rate in response to the changes in the sample's weight‐loss rate. In nitrogen and argon, only a single‐step degradation process of the PPS was observed, but in helium, a two‐step degradation process of PPS was found. Notably, in air a four‐step degradation process of the PPS, which was hardly ever revealed by a traditional TG, was found in this investigation. The initial thermal degradation temperature Td and temperature at the first maximum weight‐loss rate Tdm1 of the PPS increased in the following order: in helium < in nitrogen < in argon < in air. The first maximum weight‐loss rate also increased with the variation of atmosphere in the order: nitrogen < air < argon < helium. The char yield at 700°C increased in the order: in air < in helium < in nitrogen < in argon. The activation energy of the major degradation process of PPS calculated based on the high‐resolution TG data was very high, increasing in the order: in nitrogen < in argon < in helium < in air. The thermal decomposition parameters of the PPS determined by the high‐resolution TG were systematically compared with those by traditional TG at a constant heating rate. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2053–2059, 2002
Fast‐responding bulk hydrogels with microstructure
Authors: Cai Wensheng , Gupta Ram B. 
Published: August 2002

AbstractA new method was used for the production of fast‐responding bulk hydrogels with microstructure (BHMs) with a high swelling ratio. These BHMs were synthesized first by the formation of poly(N‐isopropylacrylamide‐co‐acrylic acid) (NIPAAm–AA) microgel particles and then by the crosslinking of the particles with N‐isopropylacrylamide monomer. The polymer obtained had the desired microstructure but was bulk (monolithic), so it could be used in a variety of applications. The NIPAAm–AA microgel particles were characterized with transmission electron microscopy, and the formed BHMs were characterized with scanning electron microscopy. Compared with conventional bulk hydrogels, the BHMs had very high swelling ratios and much faster swelling rates attributable to the collaboration of the ionized microgel particles and bulk hydrogels. An increase in the microgel particles embedded in the BHMs provided faster hydrogel swelling. The number of ionic acrylic acid groups in the hydrogels affected their swelling behavior. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 169–178, 2002
New supports for enzyme immobilization based on copolymers of vinylene carbonate and β‐hydroxyethylene acrylate
Authors: Ding Lunhan , Li Yue , Jiang Yan , Cao Zhe , Huang Jiaxian 
Published: August 2002

AbstractVinylene carbonate (VCA), β‐hydroxyethylene acrylate, and N,N′‐methylene bisacrylamide were dissolved in water, and the aqueous solutions were copolymerized via reverse‐phase suspension copolymerization in paraffin oil. A series of hydrophilic and beaded supports containing reactive cyclic carbonate groups for enzyme immobilization were obtained. The supports were examined by coupling with trypsin, and the results showed that the amount of enzymes coupled to the supports and the specific activity of the immobilized trypsin were related to the content of VCA structure units and the reaction time. Meanwhile, the optimal pH and temperature, as well as the Michaelis–Menten constant Km, for both native and immobilized trypsin were measured. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 94–102, 2002
Electrochemical deposition of polyaniline–polypyrrole composite coatings on aluminum
Authors: Akundy Gouri Smitha , Rajagopalan Ramakrishnan , Iroh Jude O. 
Published: August 2002

AbstractThe electrodeposition of polyaniline–polypyrrole composite coatings on aluminum was successfully performed by using cyclic voltammetry. Oxalic acid was used as the electrolyte. Electrodeposition was carried out at a scan rate of 20 mV/s by varying the number of cycles. An anodic peak current at around −0.1 V versus saturated calomel electrode (SCE) was observed in the cyclic voltammograms. This peak is due to the oxidation and adsorption of hydrogen. The cyclic voltammograms also show another anodic peak current at around 1.0 V versus SCE, which is the characteristic peak of the polyaniline–polypyrrole composite. The behavior of this peak with respect to the number of cycles is discussed in detail. A corresponding cathodic peak current at around −0.7 V versus SCE was also observed in the cyclic voltammograms. The infrared spectra of the composite coatings revealed the infrared peaks of both polypyrrole and polyaniline. The scanning electron micrographs of the coatings indicate a morphology completely different from its homopolymers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1970–1977, 2002
Postpolymerization of vinyl acetate‐containing latexes
Authors: Ilundain Pedro , Da Cunha Louis , Salazar Rafael , Alvarez Daniel , Barandiaran María J. , Asua José M. 
Published: August 2002

AbstractThe postpolymerization of vinyl acetate (VAc)‐containing latexes with tert‐butyl hydroperoxide (TBH)/ascorbic acid (AsA) as a redox initiation system was investigated. Volatile organic compounds (VOCs) such as acetone and tert‐butyl alcohol were produced in this process. The influence of the TBH/AsA ratio, initiator concentration, reaction temperature, and feeding time on the reduction of residual VAc and VOC formation during the postpolymerization was investigated. A total reduction of residual VAc monomer was achieved, with the formation of VOCs kept within acceptable limits. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 923–928, 2002
High‐retention properties for Hg(II) ions of a resin containing ammonium and pyridine groups
Authors: Rivas Bernabé L. , Ovando Paulina , Villegas Sandra 
Published: August 2002

AbstractThe metal‐ion uptake behavior of the chelating resin poly([(3‐(methacryloylamino)propyl] trimethyl ammonium chloride‐co‐4‐vinyl pyridine) has been investigated. The resin is obtained by radical copolymerization in a yield of 99.6%. The hydrophilic resin shows a high retention capacity and selectivity toward Hg(II) ions in the presence of Cu(II), Pb(II), Cd(II), Zn(II), and Cr(III) ions. A retention of Hg(II) higher than 99% is observed after 5 min. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2595–2599, 2002
New polymer bipolar plates for polymer electrolyte membrane fuel cells: Synthesis and characterization
Authors: Del Río C. , Ojeda M. C. , Acosta J. L. , Escudero M. J. , Hontañón E. , Daza L. 
Published: August 2002

AbstractCarbon black (CB) and polyvinylidene fluoride (PVDF) composites were obtained and subsequently characterized, both microstructurally (DSC and DMA) and electrically. In addition, the electrochemical performance of these materials was tested in the form of bipolar plates, expressly manufactured for this purpose and incorporated in a conventional fuel cell. The results obtained allow for the conclusion that CB incorporation into PVDF yields polymer composite materials with electrical conductivity of about 2.4 S/cm, which may be thermically processed and given any convenient shape with the means conventionally applied in the field of polymer technologies. It was found that CB concentration slightly affects the microstructural parameters of the composites (melting temperature, glass‐transition temperature, Avrami kinetic parameters, etc.). © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2817–2822, 2002; DOI 10.1002/app.10257
Dynamic mechanical properties and hysteresis loss of epoxidized natural rubber chemically bonded to the silica surface
Authors: Manna Ajay K. , De P. P. , Tripathy D. K. 
Published: August 2002

AbstractHigh‐temperature (180°C) molding of epoxidized natural rubber (ENR) filled with precipitated silica leads to chemical bond formation between epoxy groups of ENR and silanol groups of silica. The extent of chemical bond formation is further enhanced in the presence of the silane coupling agent N‐3‐N‐(vinyl benzyl amino)ethyl‐γ‐amino‐propyl trimethoxy silane mono hydrogen chloride (trade name Z‐6032). The results of hysteresis loss measurements show that hysteresis loss increases with increase in coupling agent loading as a result of the higher modulus of the compounds compared to that of the ENR–silica mix. The dynamic mechanical property measurements show that the addition of coupling agent increases the glass‐transition temperature. Whereas strain‐dependent dynamic mechanical properties show that filler structure breakdown increases with increasing loading of coupling agent. Sulfur‐cured systems show higher filler structure breakdown compared to that of nonsulfur systems. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2171–2177, 2002
Preparation and mechanical properties of composite of fibrous cellulose and maleated polyethylene
Authors: Zhang Farao , Endo Takashi , Qiu Wulin , Yang Liqun , Hirotsu Takahiro 
Published: August 2002

AbstractFibrous cellulose and maleated polyethylene (FC–MPE) composites were prepared under melt mixing by maleation of polyethylene (PE) to obtain maleic anhydride (MA) grafted PE (MPE) and successive compounding of the resultant MPE with fibrous cellulose (FC). When increasing the content of added MA to 2 wt %, the grafting efficiency of MA decreases gradually to 84% and the grafted MA chains become longer. Scanning electron microscopy (SEM) reveals strong adhesion of MPE to FC in the FC–MPE composite, which is probably due to the increased compatibility between MPE and FC, in contrast to no adhesion of unmaleated PE (UPE) to FC in the FC–UPE composite. This difference in interfacial structure between the FC–MPE and FC–UPE composites results in quite different mechanical properties for them. With an increase in the FC content to 60 wt %, the tensile strength of the FC–MPE composite increases significantly and reaches 125% that of pure PE. Furthermore, the larger Young's modulus, larger bending elastic modulus, and smaller elongation of the FC–MPE composite strongly indicate effective transfer of the high tensile strength and elasticity of FC to the MPE matrix through the strong adhesion between FC and MPE. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1971–1980, 2002; DOI 10.1002/app.10428