bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sex identification assay useful in great apes is not diagnostic in a range of other primate species
Authors: Ensminger Amanda L. , Hoffman Susan M.G. 
Published: August 2002

AbstractThe ability to identify the sex of individuals from noninvasive samples can be a powerful tool for field studies. Amelogenin, a nuclear gene proximate to the pseudoautosomal region of mammalian sex chromosomes, has a 6 base‐pair (bp) size difference between human X and Y chromosomes that can be PCR‐amplified and sized to distinguish male from female DNA. We examined whether this test can be used to identify sex from different DNA sources across a number of nonhuman primate taxa. Using human amelogenin primers, we were able to amplify diagnostic products from the four great ape species tested, but products from five other primate species were not sexually dimorphic. Am. J. Primatol. 56:129–134, 2002. © 2002 Wiley‐Liss, Inc.
Geometric morphometric study of the regional variation of modern human craniofacial form
Authors: Hennessy Robin J. , Stringer Chris B. 
Published: August 2002

AbstractThe regional variability of the modern human craniofacial form is of importance to debates about human origins. The study of craniofacial form has generally been carried out either by interlandmark distance measurement and analysis or by observation and character scoring. In this study of four modern human groups (Eskimo/Inuit, African, Australian, and Romano‐British), nine craniofacial landmark coordinates were recorded by extraction from laser scans. The coordinates were studied by geometric morphometrics, and a regression analysis was used to investigate the dominant variability in shape within and between groups. Statistical tests of shape difference between groups were carried out. By these methods, the statistical patterns of shape variability and their geometric interpretations were studied on a common basis. The results were found to be in agreement with the classic studies of Howells ([1989:189] Pap Peabody Mus 79), and show the potential of this approach for future research. Am J Phys Anthropol 117:37–48, 2002. © 2002 Wiley‐Liss, Inc.
Male orangutan subadulthood: A new twist on the relationship between chronic stress and developmental arrest
Authors: Maggioncalda Anne N. , Czekala Nancy M. , Sapolsky Robert M. 
Published: August 2002

AbstractBoth in the wild and in captivity, a marked and enduring arrest of secondary sexual developmental occurs in some male orangutans (Pongo pygmaeus) (Kingsley [1982] The Orang‐Utan: Its Biology and Conservation, The Hague: Junk; Utami [2000]). Researchers have hypothesized that chronic stress, perhaps related to aggression from mature males, causes endocrine changes altering growth and maturation rates in these males (Maple [1980] Orangutan Behavior, New York: Van Nostrand Reinhold; Graham [1988] Orangutan Biology, Oxford: Oxford University Press). In this study, urine samples were collected over a 3‐year period from 23 captive male orangutans to test the hypothesis that developmentally arrested male orangutans have an endocrine profile consistent with chronic stress. Three study males were juveniles, seven were arrested adolescents, six were developing adolescents, and seven were mature adults. Morning samples were analyzed by radioimmunoassay for levels of the stress hormones cortisol and prolactin, and group hormone profiles were compared by analysis of variance. Results indicate that developing adolescent male orangutans have a significantly higher stress hormone profile than juvenile, developmentally arrested adolescent, or adult males. These results imply that the arrest of secondary sexual development in some male orangutans is not stress‐induced, but instead perhaps an adaptation for stress avoidance during the adolescent or “subadult” period. These data, together with previously reported data on levels of gonadotropins, testicular steroids, and growth‐related hormones, define endocrine profiles associated with alternative reproductive strategies for males with and males without secondary sexual features (Maggioncalda et al. [1999], [2000]. Am J Phys Anthropol 118:25–32, 2002. © 2002 Wiley‐Liss, Inc.
Analysis of tufted capuchin (Cebus apella) courtship and sexual behavior repertoire: Changes throughout the female cycle and female interindividual differences
Authors: Carosi Monica , Visalberghi Elisabetta 
Published: August 2002

AbstractSexual solicitations and initiative (proceptivity, sensu Beach [1976] Horm Behav 7:105–138) are important components of the sexuality of females of many primate species. In the tufted capuchin (Cebus apella), female proceptivity characterizes the species' mating system. In study 1, we defined and discussed 20 behavioral patterns based on the observation of 6 females and 5 males living in two social groups. In study 2, each behavior, including mounting activity, was quantitatively assessed during the periovulatory and nonperiovulatory cycle phases of 4 females, detected on the basis of urinary progestin levels (N = 20 ovulatory cycles, 5 for each female); moreover, we monitored changes in females' social interactions (agonism, grooming activity, and play). Nine of the behaviors typically used by the female during courtship and in sexual interactions showed a dramatic increase during the periovulatory phase. Though males mounted females at an apparently higher rate during the periovulatory than the nonperiovulatory phase, the difference was not significant. However, when adult male mounting is separated into those which occur within play and nonplay contexts, there is a significant periovulatory phase effect for mounts not associated with play. Females groomed adult males at the same rate throughout the cycle. Agonism and play did not show any phase effect; however, females' avoidance of adult males significantly increased during the periovulatory phase. Finally, each female made a statistically different use of the behavioral repertoire by performing some behaviors more than others. This variability among females during courtship calls for further research into whether it affects mating success. Am J Phys Anthropol 118:11–24, 2002. © 2002 Wiley‐Liss, Inc.
Cell death in experimental intracerebral hemorrhage: The “black hole” model of hemorrhagic damage
Authors: Felberg Robert A. , Grotta James C. , Shirzadi Ali L. , Strong Roger , Narayana Ponnada , Hill‐Felberg Sandra J. , Aronowski Jaroslaw 
Published: August 2002

AbstractIntracerebral hemorrhage (ICH) has a poor prognosis that may be the consequence of the hematoma's effect on adjacent and remote brain regions. Little is known about the mechanism, location, and severity of such effects. In this study, rats subjected to intracerebral blood injection were examined at 100 days. Stereology (neuronal count and density) and volume measures in the perihematoma rim, the adjacent and overlying brain, and the substantia nigra pars reticulata (SNr) were compared with contralateral brain regions at 100 days and the perihemorrhage region at 24 hours and 7 days. In addition, cytochrome c release was investigated at 24 hours, 3 days, and 7 days. At 100 days, post‐ICH rats showed no difference in neuronal density in the perihemorrhagic scar region or regions of the striatum immediately surrounding and distal to the perihemorrhage scar. The cell density index in the ipsilateral field was 16.2 ± 3.8 versus the contralateral control field of 15.6 ± 3.2 (not significant). Volume measurements of the ipsilateral striatum revealed a 20% decrease that was compensated by an increase in ipsilateral ventricular size. The area of the initial ICH as measured by magnetic resonance imaging correlated with the degree of atrophy. In the region immediately surrounding the hematoma, cytochrome c immunoreactivity increased at 24 hours and 3 days, and returned toward baseline by day 7. At 24 hours, stereology in the peri‐ICH region showed decreased density in the region where cytochrome c immunoreactivity was the highest. Neuronal density of the ipsilateral SNr was significantly less than the contralateral side (9.6 ± 1.9 vs 11.6 ± 2.3). Histologic damage from ICH occurred mainly in the immediate perihemorrhage region. Except for SNr, we found no evidence of neuronal loss in distal regions. We have termed this continued destruction of neurons, which occurs over at least 3 days as the neurons come into proximity to the hematoma, the “black hole” model of hemorrhagic damage.
Plasticization of cellulose diacetate by graft copolymerization of ε‐caprolactone and lactic acid
Authors: Teramoto Yoshikuni , Yoshioka Mariko , Shiraishi Nobuo , Nishio Yoshiyuki 
Published: August 2002

AbstractGraft copolymerization of ε‐caprolactone (CL) and lactic acid (LA) onto cellulose diacetate (CDA) at the residual hydroxyl positions was conducted to obtain thermoplastic CDA. The effects of the reaction temperature and time and the CL/LA molar ratio in the feed on the progress of the graft copolymerization were investigated. The molecular weight of CDA was increased by this graft copolymerization. The oxycaproyl and lactyl molar substitutions (MSCLand MSLA, respectively) in grafted CDA (g‐CDA) were determined through1H‐NMR spectral analysis. These MS values were controllable by changing the reaction conditions adequately. The flow temperature and melt viscosity ofg‐CDA decreased with an increase in the total substitution of MSCLand MSLA, and transparent polymer sheets could be obtained from the resultingg‐CDA by hot pressing at around 200°C without adding any plasticizer. The mechanical properties of the moldedg‐CDA samples varied widely, depending on the different combinations of the MSCLand MSLAvalues; theg‐CDA sheets became elastic when the MSCLwas larger than the MSLA, and their tensile strengths were enhanced as the MSLAwas increased. It was thus found that CDA was successfully plasticized by this graft copolymerization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2621–2628, 2002
Mechanical properties and deformation mechanisms in high thermal resistant poly(acrylonitrile‐butadiene‐styrene) under static tension and Izod impact
Authors: Jar P.‐Y. B. , Creagh D. C. , Konishi K. , Shinmura T. 
Published: August 2002

AbstractDeformation mechanisms in a high thermal resistant poly(acrylonitrile‐butadiene‐styrene) (ABS) were investigated using transmission electron microscopy (TEM) and small‐angle X‐ray scattering (SAXS). The work followed our previous study, in which TEM was used for the craze observation and SAXS for the shear yielding, to evaluate the relationship between the mechanical properties and the deformation mechanisms of the ABS under static tension and Izod impact. The current results support our previous conclusion that the combination of TEM and SAXS enables us to identify the deformation mechanisms in the ABS, and provide new evidence for the coexistence of crazing and shear yielding. The SAXS patterns suggest that shear yielding occurred in the ABS, even under the impact loading. We concluded from the study that the occurrence of shear yielding had a major effect on the toughness enhancement of the ABS. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 17–24, 2002
pH‐sensitive shrinking of a dextran sulfate/chitosan complex gel and its promotion effect on the release of polymeric substances
Authors: Sakiyama Takaharu , Takata Hajime , Toga Takehiro , Nakanishi Kazuhiro 
Published: August 2002

AbstractA pH‐sensitive gel was prepared by polyelectrolyte complex formation between dextran sulfate and chitosan. When the complex gel contained more amino groups than sulfate groups, it shrank pronouncedly at around pH 7 in NaCl solutions of various concentrations, probably because of the deionization of protonated amino groups remaining free from electrostatic interaction with the sulfate groups. Using the complex gel loaded with dextran by absorption, releasing behaviors were studied under various conditions. It was shown that shrinking of the complex gel had a promotion effect on the release of dextran. In 170 mM NaCl solution, the complex gel released dextran more rapidly at pH 8 than at pH 2, because the degree of shrinking was greater at pH 8. Thus, the promotion effect of the complex gel on the release of dextran was pH dependent, though the release rates at the two pHs became closer as the average molecular weight of dextran loaded was lowered. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 667–674, 2001
Release and diffusion of sulfamethoxazole through acrylamide‐based hydrogel
Authors: Bajpai A. K. , Rajpoot M. 
Published: August 2002

AbstractTwo polymeric hydrogels (xerogels) containing poly(vinyl pyrrolidone) (PVP)‐crosslinked polyacrylamide and poly(vinyl alcohol) (PVA)‐crosslinked polyacrylamide were loaded with the sulfamethoxazole drug and their swelling and drug‐release dynamics were investigated at a fixed pH and at room temperature (27°C). The effects of various factors such as the composition of the xerogel, crosslinking density, and drug loading were studied on the swelling and drug‐release pattern of the xerogels. The kinetic parameters such as the diffusion exponent (n), diffusion constant (k), and diffusion coefficient (D) were also evaluated and analyzed. The percent drug released by these xerogels was also compared to that by the crosslinked gelatin gels. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1238–1247, 2001
Plasma‐induced graft polymerization of acrylic acid onto poly(ethylene terephthalate) films
Authors: Gupta Bhuvanesh , Hilborn Jons G. , Bisson Isabelle , Frey Peter 
Published: August 2002

AbstractThe graft polymerization of acrylic acid was carried out onto poly(ethylene terephthalate) films that had been pretreated with argon plasma and subsequently exposed to oxygen to create peroxides. The influence of synthesis conditions, such as plasma treatment time, plasma power, monomer concentration, temperature, and the presence of Mohr's salt, on the degree of grafting was investigated. The observed initial increase in grafting with monomer concentration accelerated at about 20% monomer. The grafting reached a maximum at 40% monomer and subsequently decreased with further increases in monomer concentration. The reaction temperature had a pronounced effect on the degree of grafting. The initial rate of grafting increased with increasing temperature, but the degree of grafting showed a maximum at 50°C. The activation energy of the grafting obtained from an Arrhenius plot was 29.1 kJ/mol. The addition of Mohr's salt to the reaction medium not only led to a homopolymer‐free grafting reaction but also diminished the degree of grafting. The degree of grafting increased with increasing plasma power and plasma treatment time. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2993–3001, 2001
Electrically conductive, melt‐processed polyaniline/EVA blends
Authors: Barra Guilherme M. O. , Leyva Maria Elena , Soares Bluma G. , Mattoso L. H. , Sens Marcio 
Published: August 2002

AbstractMechanical blends of ethylene–vinyl acetate copolymer and polyaniline doped with dodecyl benzene sulfonic acid (PAni–DBSA) were prepared in a two‐roll mill at 50°C and in a Haake internal mixer at 150°C. The effects of the blend composition and processing conditions on the electrical conductivity and mechanical properties were investigated. These blends exhibited high levels of electrical conductivity at a small amount of PAni complex. Blends prepared in a two‐roll mill displayed conductivity values as high as 1 S/cm and a higher protonation degree than the pure PAni–DBSA, as indicated by X‐ray photoelectron spectroscopy. Two different insulator–conductor transition points were observed in these blends. The mechanical performance decreased as the amount of PAni–DBSA increased, indicating blend incompatibility and a plasticizing effect of the DBSA. The morphology of the blends were studied by scanning electron microscopy. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 114–123, 2001
In vitrodegradation behavior of carbon fiber‐reinforced PLA composites and influence of interfacial adhesion strength
Authors: Wan Y. Z. , Wang Y. L. , Xu X. H. , Li Q. Y. 
Published: August 2002

AbstractIn the present study, carbon fiber‐reinforced polylactide (C/PLA) composites with different interfacial conditions were prepared to determine the influence of interfacial adhesion strength (IAS) onin vitrodegradation behavior of the C/PLA composites. Pure PLA and untreated and treated C/PLA composite samples were immersed in phosphate buffered saline (PBS; pH 7.4, 37 ± 0.5°C) for predetermined time periods. These samples were removed at each degradation time, measured to analyze molecular weight loss, weighed to assess water uptake and mass loss, and mechanically tested to obtain bending strength, modulus, and IAS. The matrixes in the C/PLA composites showed higher water uptake and lower mass loss in comparison with the pure PLA. Further, the PLA matrix in the treated composite absorbed less water and lost less mass and molecular weight than its counterpart in the untreated composite. Mechanical tests confirmed that the treated C/PLA composite exhibited a slower rate of decrease in bending strength, modulus, and IAS than the untreated one. The differences in degradation behavior between two composites can only be attributed to the difference in interfacial conditions because all other parameters were kept constant. The loss of bending strength and modulus was mainly caused by the interface degradation of the C/PLA composites. It can be concluded from ourin vitroobservations that the IAS had an obvious influence on the degradation characteristics of the C/PLA composites. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 150–158, 2001
Clay nanolayer reinforcement of cis‐1,4‐polyisoprene and epoxidized natural rubber
Authors: Vu Yen T. , Mark James E. , Pham Ly H. , Engelhardt Martin 
Published: August 2002

AbstractConditions were established for dispersing clay nanolayers into both cis‐1,4‐polyisoprene (synthetic) natural rubber (NR) and epoxidized natural rubbers (ENR) having 25 or 50 mol % epoxide. The clay was a sodium montmorillonite and was used as a pristine layered silicate or as organically modified layered silicates to make the galleries more hydrophobic and thus more compatible with the elastomers. The chemical modifications were carried out using an ion‐exchange reaction with alkyl ammonium cations. Incorporation of the clays into the elastomers was achieved by mixing the components themselves in a standard internal blender or by mixing dispersions of them in toluene or methyl ethyl ketone. X‐ray diffraction results indicated intercalation of NR and ENR into the silicate interlayers, followed by exfoliation of the silicate layers into the elastomer matrices. Of primary interest was the effect of the intercalated and exfoliated clays on the mechanical properties of the elastomers. The reinforcing effects obtained were found to depend strongly on the extent of the dispersion of the silicate layers into the rubber matrices. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1391–1403, 2001
Large volume, high‐performance applications of fibers in civil engineering
Authors: Li Victor C. 
Published: August 2002

AbstractThis article presents an overview of fiber applications in cementitious composites. The socio‐economic considerations surrounding materials development in civil engineering in general, and fiber reinforced cementitious materials in particular, are described. Current FRC appliations are summarized, and the where, how, and why fibers are used in these applications, are documented. An attempt is made to extract common denominators among the widely varied applications. The R&D and industrial trends of applying fibers in enhancing structural performance are depicted. An actual case study involving a tunnel lining constructed in Japan is given to illustrate how a newly proposed structural design guideline takes into account the load carrying contribution of fibers. Composite properties related to structural performance are described for a number of FRCs targeted for use in load carrying structural members. Structural applications of FRCs are currently under rapid development. In coming years, it is envisioned that the ultra‐high performance FRC, with ductility matching that of metals, will be commercially exploited in various applications. Highlights of such a material are presented in this article. Finally, conclusions on market trends are drawn, and favorable fiber characteristics for structural applications are provided. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 660–686, 2002
Synthesis and characterization of biodegradable poly(ester‐urethanes) based on bacterial poly(R‐3‐hydroxybutyrate)
Authors: Saad Gamal R. , Lee Y. J. , Seliger H. 
Published: August 2002

AbstractA series of poly(R‐3‐hydroxybutyrate)/poly(ε‐caprolactone)/1,6‐hexamethylene diisocyanate‐segmented poly(ester‐urethanes), having different compositions and different block lengths, were synthesized by one‐step solution polymerization. The molecular weight of poly(R‐3‐hydroxybutyrate)‐diol, PHB‐diol, hard segments was in the range of 2100–4400 and poly(ε‐caprolactone)‐diol, PCL‐diol, soft segments in the range of 1080–5800. The materials obtained were investigated by using differential scanning calorimetry, wide angle X‐ray diffraction and mechanical measurements. All poly(ester‐urethanes) investigated were semicrystalline withTmvarying within 126–148°C. DSC results showed thatTgare shifted to higher temperature with increasing content of PHB hard segments and decreasing molecular weight of PCL soft segments. This indicates partial compatibility of the two phases. In poly(ester‐urethanes) made from PCL soft segments of molecular weight(Mn≥ 2200), a PCL crystalline phase, in addition to the PHB crystalline phase, was observed. As for the mechanical tensile properties of poly(ester‐urethane) cast films, it was found that the ultimate strength and the elongation at the breakpoint decrease with increasing PHB hard segment content. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 703–718, 2002
In situ heparin‐induced peroxisomal reticulum and biogenesis of peroxisomes in pulmonary intravascular macrophages (PIMs) of caprine lung: an ultrastructural and cytochemical study
Authors: Atwal Onkar S. , Williams Carol S. , Minhas Kanwal J. , Nijjar Mohinder S. 
Published: August 2002

AbstractPulmonary intravascular macrophages (PIMs) contain a unique electron‐dense globular surface‐coat which is sensitive to heparin treatment, halothane anesthesia, and the digestive effect of lipolytic lipase (LPL), suggesting that the coat is predominantly composed of lipoproteins. In the present study, evidence is presented that heparin, when administered intravenously in goats, potentiated both the translocation of the surface‐coat into the vacuolar system and the expansion of the Golgi apparatus. Sequentially, these changes were followed by proliferation of peroxisomes in combination with peroxisomal reticulum (PR), a transient precursor of this organelle. The peroxisomes, as well as PR, reacted positively for catalase after aldehyde fixation and 3,3′‐diaminobenzidine (DAB) staining. In addition to their role as phagocytes, the ultrastructural and cytochemical detection of peroxisomes suggests a functional capacity of the PIMs, which may be adaptable to the circulating level of free fatty acids (FAAs). Anat Rec 266:69–80, 2002. © 2002 Wiley‐Liss, Inc.