bluuebunny/crossref_metadata_2025 huggingface dataset:
Distribution of viral antigen and development of lesions after experimental infection with highly virulent bovine viral diarrhea virus type 2 in calves
Authors: Liebler-Tenorio Elisabeth M. , Ridpath Julia F. , Neill John D.
Published: December 2005

Objective—To correlate tissue distribution with development of lesions after experimental infection with a virulent strain of noncytopathic bovine viral diarrhea virus (BVDV) type 2 in calves.

Animals—Ten 14-day-old and two 2-month-old colostrum-deprived calves.

Procedure—Calves were intranasally inoculated with BVDV type-2 strain 1373 from an outbreak of clinically severe bovine viral diarrhea (BVD). Two 14-day-old calves served as noninfected controls. Two calves each were euthanatized on postinoculation days 3, 6, and 12, and 1 each on days 8, 9, 13, and 14. Tissues were collected for immunohistologic and histologic examination.

Results—Inoculated calves developed nonspecific clinical signs characterized by high fever and decreased numbers of leukocytes and thrombocytes. Viral antigen was detected focally in lymphoid tissues on day 3. On days 6, 8, 9, 12, and 14, viral antigen became increasingly widespread throughout organs and tissues. Viral antigen in lymphoid tissues was associated with severe depletion of all compartments. Lesions in other tissues were not well correlated with distribution of viral antigen. Depletion of lymphoid tissues was observed in a calf on day 13, but viral antigen had been cleared from most tissues and was detected in vascular walls only.

Conclusions and Clinical Relevance—Infection with a virulent BVDV strain resulted in wide dissemination of viral antigen in host tissues. Severe lymphoid depletion developed in lymphoid tissues, whereas viral antigen was generally not associated with lesions in other tissues. Findings suggest that development of lesions in acute BVD is not solely a function of viral replication and is also attributable to host reaction to infection. (Am J Vet Res2002;63:1575–1584
Purification and partial characterization of canine pepsinogen A and B
Authors: Suchodolski Jan S. , Steiner Jörg M. , Ruaux Craig G. , Boari Andrea , Williams David A.
Published: December 2005

Objective—To purify and partially characterize various
isoforms of canine pepsinogen (PG) from gastric
mucosa.

Sample Population—Stomachs obtained from 6
euthanatized dogs.

Procedure—Mucosa was scraped from canine stomachs,
and a crude mucosal extract was prepared and
further purified by use of weak anion-exchange chromatography,
hydroxyapatite chromatography, sizeexclusion
chromatography, and strong anionexchange
chromatography. Pepsinogens were characterized
by estimation of molecular weights, estimation
of their isoelectric points (IEPs), and N-terminal
amino acid sequencing.

Results—Two different groups of canine PG were
identified after the final strong anion-exchange chromatography:
PG A and PG B. Pepsinogens differed in
their molecular weights and IEP. Pepsinogen B
appeared to be a dimer with a molecular weight of
approximately 34,100 and an IEP of 4.9. Pepsinogen
A separated into several isoforms. Molecular weights
for the various isoforms of PG A ranged from 34,200
to 42,100, and their IEPs ranged from 4.0 to < 3.0. The
N-terminal amino acid sequence for the first 25 amino
acid residues for PG A and B had good homology with
the amino acid sequences for these proteins in other
species.

Conclusions and Clinical Relevance—Canine PG B
and several isoforms of canine PG A have been purified.
Availability of these PGs will facilitate development
of immunoassays to measure PG in canine
serum as a potential diagnostic marker for gastric disorders
in dogs. (Am J Vet Res 2002;63:1585–1590)
Computer-assisted image analysis of neovascularization in thyroid neoplasms from dogs
Authors: Kent Michael S. , Griffey Stephen M. , Verstraete Frank J. M. , Naydan Diane , Madewell Bruce R.
Published: December 2005

Objective—To develop a computer-assisted image analysis procedure for quantitation of neovascularization in formalin-fixed paraffin-embedded specimens of thyroid gland tissue from dogs with and without thyroid gland neoplasia.

Sample Population—47 thyroid gland carcinomas, 8 thyroid gland adenomas, and 8 specimens of thyroid tissue from dogs without thyroid gland abnormalities (normal).

Procedure—Serial tissue sections were prepared and stained with antibodies against human CD31 or factor VIII-related antigen (factor VIII-rag). The areas of highest vascularity were identified in CD31- stained sections, and corresponding areas were then identified in factor VIII-rag-stained sections. Image analysis was used to calculate the total vascular density in each section, and neovascularization, expressed as a percentage, was determined as the absolute value of the total vascular density derived from factor VIII-rag-stained sections minus the vascular density derived from CD31-stained sections.

Results—Mean vascular density of thyroid gland carcinomas derived from CD31-stained sections was significantly greater than density derived from factor VIII-rag-stained sections. This incremental difference was presumed to represent degree of neovascularization. However, significant differences were not detected between vascular densities derived from CD31 and factor VIII-rag-stained sections for either normal thyroid gland tissue or thyroid gland adenomas. No significant correlations were found between vascular density in thyroid gland carcinomas and survival time following surgery.

Conclusion and Clinical Relevance—A computerassisted image analysis method was developed for quantifying neovascularization in thyroid gland tumors of dogs. This method may allow identification of dogs with tumors that are most likely to respond to treatment with novel antiangiogenesis agents. (Am J Vet Res2002;63:363–369)
Evaluation of a bladder tumor antigen test for the diagnosis of lower urinary tract malignancies in dogs
Authors: Billet Jean-Philippe H.G. , Moore Alasdair Hotston , Holt Peter E.
Published: December 2005

Objective—To evaluate the use of a human bladder tumor antigen test for diagnosis of lower urinary tract malignancies in dogs.

Sample Population—Urine samples from dogs without urinary tract abnormalities (n = 18) and from dogs with lower urinary tract neoplasia (20) or nonmalignant urinary tract disease (16).

Procedure—Test results were compared among groups and among 3 observers. The effects of urine pH and specific gravity, degree of hematuria, and storage temperature and time of urine samples on test results were also assessed.

Results—Test sensitivity and specificity were 90 and 94.4%, respectively, for differentiating dogs with lower urinary tract neoplasia from dogs without abnormalities. However, specificity decreased to 35% for differentiating dogs with neoplasia from dogs with nonmalignant urinary tract disease. In dogs with neoplasia, results were significantly affected by degree of hematuria. However, addition of blood to urine from dogs without hematuria had no significant effect on test results. Although intraobserver variation was significant, urine pH, specific gravity, or storage time or temperature had no significant effect on results.

Conclusions and Clinical Relevance—Although this bladder tumor antigen test was sensitive for differentiating dogs with malignancies of the lower urinary tract from dogs without urinary tract disease, it was not specific for differentiating dogs with neoplasia from dogs with other lower urinary tract abnormalities. It cannot, therefore, be recommended as a definitive diagnostic aid for the detection of lower urinary tract malignancies in dogs. (Am J Vet Res2002;63:370–373)
Clinical and pathologic analyses of bicipital tenosynovitis in dogs
Authors: Gilley Robert S. , Wallace Larry J. , Hayden David W.
Published: December 2005

Objective—To determine the clinical and pathologic findings in dogs with primary bicipital tenosynovitis.

Animals—19 dogs with 20 shoulder joints treated surgically for bicipital tenosynovitis and 8 shoulder joints from 4 clinically normal dogs.

Procedure—Histologic abnormalities of tendon sheaths of the biceps brachii in affected dogs were determined by use of comparison with findings in clinically normal dogs. Specimens were graded for inflammation, fibrosis, villous hypertrophy, vascular prominence, and synovial cell proliferation. Histopathologic results were statistically evaluated for relationship with clinical findings and treatment before surgery.

Results—Synovial villous hypertrophy and vascular prominence were the most consistent histologic findings in 16 and 14 of 20 affected joints, respectively. Evidence of inflammation was lacking in 6 joints. Ten joints had inflammatory cell infiltration of the tendon sheath. Plasma cells and lymphocytes were the most common infiltrates; however, the type and amount of inflammatory cell infiltrate were variable. Fibrosis of the tendon sheath was seen in 8 joints, and synovial cell proliferation was seen in 11 joints. Other changes included accumulation of hemosiderin, focal calcification, osseous metaplasia, lysis of collagen, and fibrocartilaginous metaplasia. No significant relationship was detected between histopathologic findings and clinical findings or treatment before surgery.

Conclusions and Clinical Relevance—Inflammation was more variable than hypothesized and may not be a consistent pathophysiologic feature of bicipital tenosynovitis. In some dogs, this disease may be the result of a degenerative process rather than an inflammatory process. (Am J Vet Res2002;63:402–407)
Effects of nonesterified fatty acids and β-hydroxybutyrate on functions of mononuclear cells obtained from ewes
Authors: Lacetera Nicola , Franci Ombretta , Scalia Daniela , Bernabucci Umberto , Ronchi Bruno , Nardone Alessandro
Published: December 2005

Objective—To assess the effects of nonesterified fatty acids (NEFA) and β-hydroxybutyrate (BHBA) on functions of mononuclear cells obtained from ewes.

Animals—6 Sardinian ewes.

Procedure—Mononuclear cells were cultured with concentrations of NEFA (0, 15.6, 31.2, 62.5, 125, 250, 500, 1,000, or 2,000 µmol/L) and BHBA (0, 0.45, 0.9, 1.8, or 3.6 mmol/L). Concentrations of NEFA and BHBA were intended to mimic those of ketotic or healthy ewes, and NEFA and BHBA were tested alone and in combination. Synthesis of DNA was stimulated by use of concanavalin A (Con A) or pokeweed-mitogen (PWM). Secretion of IgM was stimulated by use of PWM.

Results—Synthesis of DNA stimulated by Con A and PWM was significantly inhibited by high concentrations of NEFA (≥ 250 µmol/L) or by a combination of high concentrations of NEFA (≥ 250 µmol/L) and all concentrations of BHBA (≥ 0.45 mmol/L). In contrast, DNA synthesis was not inhibited by low concentrations of NEFA (≤ 125 µmol/L) or by a combination of low concentrations of NEFA (≤ 125 µmol/L) and the lowest concentration of BHBA (0.45 mmol/L). Secretion of IgM was significantly inhibited by all concentrations of NEFA and by all combinations of NEFA and BHBA concentrations. When used alone, none of the concentrations of BHBA inhibited DNA synthesis or IgM secretion.

Conclusions and Clinical Relevance—Reduced immunoresponsiveness during ketosis is likely to be associated with an increase in plasma concentration of NEFA and not with an increase in plasma concentration of BHBA. (Am J Vet Res2002;63:414–418)
Plasma concentrations of endothelin-like immunoreactivity in healthy horses and horses with naturally acquired gastrointestinal tract disorders
Authors: Ramaswamy Chidambaram M. , Eades Susan C. , Venugopal Changaram S. , Hosgood Giselle L. , Garza Frank , Barker Steven A. , Moore Rustin M.
Published: December 2005

Objective—To compare plasma endothelin (ET)- like immunoreactivity between healthy horses and those with naturally acquired gastrointestinal tract disorders.

Animals—29 healthy horses and 142 horses with gastrointestinal tract disorders.

Procedure—Blood samples were collected from healthy horses and from horses with gastrointestinal tract disorders prior to treatment. Magnitude and duration of abnormal clinical signs were recorded, and clinical variables were assessed via thorough physical examinations. Plasma concentrations of ET-like immunoreactivity were measured by use of a radioimmunoassay for human endothelin-1, and CBC and plasma biochemical analyses were performed.

Results—Plasma ET-like immunoreactivity concentration was significantly increased in horses with gastrointestinal tract disorders, compared with healthy horses. Median plasma concentration of ET-like immunoreactivity was 1.80 pg/ml (range, 1.09 to 3.2 pg/ml) in healthy horses. Plasma ET-like immunoreactivity was greatest in horses with strangulating largeintestinal obstruction (median, 10.02 pg/ml; range, 3.8 to 22.62 pg/ml), peritonitis (9.19 pg/ml; 7.89 to 25.83 pg/ml), and enterocolitis (8.89 pg/ml; 6.30 to 18.36 pg/ml). Concentration of ET-like immunoreactivity was significantly associated with survival, PCV, and duration of signs of pain. However, correlations for associations with PCV and duration of pain were low.

Conclusions and Clinical Relevance—Horses with gastrointestinal tract disorders have increased plasma concentrations of ET-like immunoreactivity, compared with healthy horses. The greatest values were detected in horses with large-intestinal strangulating obstructions, peritonitis, and enterocolitis. This suggests a potential involvement of ET in the pathogenesis of certain gastrointestinal tract disorders in horses. (Am J Vet Res2002;63:454–458)
Clinical use of serum parvovirus and distemper virus antibody titers for determining revaccination strategies in healthy dogs
Authors: Twark Lisa , Dodds W. Jean
Published: December 2005

Objective—To assess whether serum canine parvovirus (CPV) and canine distemper virus (CDV) antibody titers can be used to determine revaccination protocols in healthy dogs.

Design—Case series.

Animals—1,441 dogs between 6 weeks and 17 years old.

Procedure—CPV and CDV antibody titers in serum samples submitted to a commercial diagnostic laboratory were measured by use of indirect fluorescent antibody (IFA) tests. On the basis of parallel measurements of CPV and CDV serum antibody titers in 61 paired serum samples determined by use of hemagglutination inhibition and serum neutralization methods, respectively, we considered titers ≥ 1:5 (IFA test) indicative of an adequate antibody response.

Results—Age, breed, and sex were not significantly associated with adequate CPV- or CDV-specific antibody responses. Of 1,441 dogs, 1,370 (95.1%) had adequate and 71 (4.9%) had inadequate antibody responses to CPV, whereas 1,346 of 1,379 (97.6%) dogs had adequate and 33 (2.4%) had inadequate responses to CDV. Vaccination histories were available for 468 dogs (468 for CPV, 457 for CDV). Interval between last vaccination and antibody measurement was 1 to 2 years for the majority (281/468; 60.0%) of dogs and 2 to 7 years for 142 of 468 (30.3%) dogs. Interval was < 1 year in only 45 of 468 (9.6%) dogs.

Conclusion and Clinical Relevance—The high prevalence of adequate antibody responses (CPV, 95.1%; CDV, 97.6%) in this large population of dogs suggests that annual revaccination against CPV and CDV may not be necessary. (J Am Vet Med Assoc2000;217:1021–1024)
Advantage of dichromats over trichromats in discrimination of color‐camouflaged stimuli in nonhuman primates
Authors: Saito Atsuko , Mikami Akichika , Kawamura Shoji , Ueno Yoshikazu , Hiramatsu Chihiro , Widayati Kanthi A. , Suryobroto Bambang , Teramoto Migaku , Mori Yusuke , Nagano Kunitoshi , Fujita Kazuo , Kuroshima Hika , Hasegawa Toshikazu
Published: December 2005

Due to a middle‐ to long‐wavelength‐sensitive (M/LWS) cone opsin polymorphism, there is considerable phenotypic variation in the color vision of New World monkeys. Many females have trichromatic vision, whereas some females and all males have dichromatic vision. The selective pressures that maintain this polymorphism are unclear. In the present study we compared the performance of dichromats and trichromats in a discrimination task. We examined tri‐ and dichromatic individuals of two species: brown capuchin monkeys (Cebus apella) and long‐tailed macaques (Macaca fascicularis). We also examined one protanomalous chimpanzee (Pan troglodytes). The subjects' task was to discriminate a circular pattern from other patterns in which textural elements differed in orientation and thickness from the background. After they were trained with stimuli of a single color, the subjects were presented with color‐camouflaged stimuli with a green/red mosaic overlaid onto the pattern. The dichromatic monkeys and the protanomalous chimpanzee selected the correct stimulus under camouflaged conditions at rates significantly above chance levels, while the trichromats did not. These findings demonstrate that dichromatic nonhuman primates possess a superior visual ability to discriminate color‐camouflaged stimuli, and that such an ability may confer selective advantages with respect to the detection of cryptic foods and/or predators. Am. J. Primatol. 67:425–436, 2005. © 2005 Wiley‐Liss, Inc.
Influence of stimuli size on color discrimination in capuchin monkeys
Authors: Gomes Úrsula R. , Pessoa Daniel M.A. , Suganuma Elisa , Tomaz Carlos , Pessoa Valdir F.
Published: December 2005

Large‐field trichromacy is a general feature of protanope and deuteranope humans, provided that the stimuli size extends to an 8° visual angle. In this study we compared the performance of five male and three female tufted capuchin monkeys (Cebus apella) in discriminating pairs of Munsell color papers. Human subjects were also studied in two‐choice discrimination tests, using the same stimuli and apparatus employed for the monkeys. The results show that although the dichromatic humans showed improved discrimination with larger versions of the stimuli, the dichromatic monkeys exhibited the same performance for both stimuli sizes. Thus, Cebus apella apparently do not present large‐field trichromacy‐at least for the conditions in the present experiments. Am. J. Primatol. 67:437–446, 2005. © 2005 Wiley‐Liss, Inc.
Color‐vision polymorphism in wild capuchins (Cebus capucinus) and spider monkeys (Ateles geoffroyi) in Costa Rica
Authors: Hiramatsu Chihiro , Tsutsui Toko , Matsumoto Yoshifumi , Aureli Filippo , Fedigan Linda M. , Kawamura Shoji
Published: December 2005

New World monkeys are unique in exhibiting a color‐vision polymorphism due to an allelic variation of the red‐green visual pigment gene. This makes these monkeys excellent subjects for studying the adaptive evolution of the visual system from both molecular and ecological viewpoints. However, the allele frequencies of the pigments within a natural population have not been well investigated. As a first step toward understanding the relationship between vision and behavior, we conducted color‐vision typing by analyzing fecal DNA from two wild groups of white‐faced capuchin monkeys (Cebus capucinus) and one group of black‐handed spider monkeys (Ateles geoffroyi) inhabiting Santa Rosa National Park of Costa Rica. All color‐typed monkeys were individually identified. InC. capucinusandA. geoffroyiwe found three and two pigment types, respectively, and the spectral mechanism that created one of the twoAtelespigments was found to be novel. In oneCebusgroup and theAtelesgroup, all alleles were present, whereas in the otherCebusgroup only two alleles were found, with one allele predominating. This was likely due to the effect of close inbreeding, indicating that wild populations can exhibit a variety of allele compositions. This result also suggests that the color‐vision polymorphism can be easily distorted by natural factors, such as inbreeding, skewing the population structure. Am. J. Primatol. 67:447–461, 2005. © 2005 Wiley‐Liss, Inc.
Color vision pigment frequencies in wild tamarins (Saguinusspp.)
Authors: Surridge A.K. , Suárez S.S. , Buchanan‐smith H.M. , Smith A.C. , Mundy N.I.
Published: December 2005

The adaptive importance of polymorphic color vision found in many New World and some prosimian primates has been discussed for many years. Polymorphism is probably maintained in part through a heterozygote advantage for trichromatic females, as such individuals are observed to have greater foraging success when selecting ripe fruits against a background of forest leaves. However, recent work also suggests there are some situations in which dichromatic individuals may have an advantage, and that variation in color vision among individuals possessing different alleles may also be significant. Alleles that confer a selective advantage to individuals are expected to occur at a higher frequency in populations than those that do not. Therefore, analyzing the frequencies of color vision alleles in wild populations can add to our understanding of the selective advantages of some color vision phenotypes over others. With this aim, we used molecular techniques to determine the frequencies of color vision alleles in 12 wild tamarin groups representing three species of the genusSaguinus. Our results show that allele frequencies are not equal, possibly reflecting different selective regimes operating on different color vision phenotypes. Am. J. Primatol. 67:463–470, 2005. © 2005 Wiley‐Liss, Inc.
Demonstration of a genotype–phenotype correlation in the polymorphic color vision of a non‐callitrichine New World monkey, capuchin (Cebus apella)
Authors: Saito Atsuko , Kawamura Shoji , Mikami Akichika , Ueno Yoshikazu , Hiramatsu Chihiro , Koida Kowa , Fujita Kazuo , Kuroshima Hika , Hasegawa Toshikazu
Published: December 2005

Color‐vision polymorphism in New World monkeys occurs because of an allelic polymorphism of the single‐copy red‐green middle‐to‐long‐wavelength‐sensitive (M/LWS) opsin gene on the X chromosome. Because color‐vision types can readily be estimated from allelic types of the M/LWS opsin gene, this polymorphic system offers researchers an excellent opportunity to study the association between vision and behavior. As a prerequisite for such studies, genetically determined color‐vision types must be concordant with phenotypes determined directly by behavioral criteria (e.g., by a color discrimination test). However, such correlations between genotypes and phenotypes have been studied only for callitrichine species. Using genetic, electrophysiological, and behavioral approaches, we evaluated the color vision of brown capuchin monkeys (Cebus apella), a representative non‐callitrichine model animal for physiology and behavior. Two allelic M/LWS opsins–P545 and P530–were identified in the studied captive population. Females had one or both of the alleles, and males had either one. The retinal sensitivity in P530 dichromats was short‐wave shifted relative to that in P545 dichromats, whereas that in P530/P545 trichromats was between the two groups. In a discrimination task using Ishihara pseudo‐isochromatic plates, P530/P545 trichromats were successful in discriminating stimuli that P530 and P545 dichromats were unable to discriminate. In a food‐search task, P530/P545 trichromats were able to locate red targets among green distracters as quickly as among white distracters, whereas both types of dichromats took longer. These results demonstrate the mutual consistency between genotypes and phenotypes of color vision, and provide a solid genetic basis on which the ecology and evolution of color vision can be investigated. Am. J. Primatol. 67:471–485, 2005. © 2005 Wiley‐Liss, Inc.
Diffusion of additives and deterioration with passage of time in polypropylene
Authors: Inata Hitoshi , Maki Ikuhiro , Ishikawa Tomoyuki , Takeda Kunihiko
Published: December 2005

The diffusion of additives and the deterioration with the passage of time in polypropylene (PP) were studied by using the UL flaming test and the oxygen index test to measure the flame retardancy. The weight change was also measured. The decreases with the lapse of time were observed for multiple flame retardants. Aliphatic brominated compounds showed the best result for flame retardancy in the initial stage of combustion. The best flame retardants for PP to inhibit the deterioration of flame retardancy with the passage of time were brominated hydrocarbon with more than two aromatic rings connected by a functional group or isocyanurate, and phosphates connected with a branching aliphatic hydrocarbon. The weight of the loss was plotted as a function of aging time and temperature to elucidate why the flame retardancy deteriorated. The apparent diffusion constant depends on the temperature and the rate was expressed with the Arrhenius equation. The concentration of flame retardant in PP was calculated by the constant and the equation at arbitrary time after thermal aging. The relation between the performance and chemical structure of the additives was also discussed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006
Preparation of collagen–polyurethane composite film and its subcutaneous implantation in rats: The improvement of tissue compatibility
Authors: Li Yanhui , Huang Yudong
Published: December 2005

This paper reports a safe, easy, effective, and one‐step process to introduce a collagen layer onto a polyester‐urethane surface for improving its biocompatibility and reducing acute inflammatory reaction. Collagen gel (COL) was spread onto the plasma‐treated polyurethanes (PU) film to make PU–COL composite film by lyophilization. In this process, collagen on the interface was covalently immobilized to PU surface. Density of immobilized collagen molecules was examined to find the optimal experiment condition. The surface properties of the immobilized film were characterized by attenuated total reflection infrared spectrum and X‐ray photoelectron spectroscopy to determine the efficiency of collagen immobilization. The results indicated that collagen chains had been grafted on PU surface because of plasma activation. To see if collagen modification can deduce acute inflammatory reaction and improve tissue guide regeneration, PU and PU–COL composite film were implanted subdermally in rats to analyze the effect of collagen immobilization. The reaction interface of PU–COL composite film and rat's tissue was observed by transmission electron microscope to analyze biocompatibility of PU–COL; unmodified PU film was used as control. The result showed that acute inflammatory reaction induced by PU–COL composite film had vanished gradually after 7 days and the material was embedded by tissue, almost forming a capsule. The capsule's wall thinned out gradually in the following days. Although the control group's inflammatory reaction did not vanish in 1 month and PU film embed in rat's tissue incompletely, PU implant migrated easily from the implant site. As a result, PU–COL composite film had most advantage in tissue guide regeneration and compatibility. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99:1832–1841, 2006
Sample size effect on the effective diffusion coefficients for the gas contained in closed‐cell polyethylene‐based foam subjected to compressive creep tests
Authors: Ruiz‐Herrero J. L. , Rodríguez‐Pérez M. A. , De Saja J. A.
Published: December 2005

In this article, the effect of sample size on the degassing behavior of closed‐cell low density polyethylene (LDPE) foam under long‐term compressive static loading is presented. The creep response was modeled by assuming isothermal compression of the gas. The change in gas pressure with time was obtained and the effective diffusion coefficients were calculated from pressure decrease using an analytical solution of the diffusion equation, and were found to increase when the sample size was reduced. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006
Study on sepiolite‐reinforced polymeric nanocomposites
Authors: Zheng Yaping , Zheng Ying
Published: December 2005

Epoxy nanocomposites reinforced by nano‐sized sepiolite are investigated. Sepiolite particles and the nanocomposites were characterized by SEM, TEM, XRD, and IR. The level of reinforcement is assessed from impact strength and flexural strength. It is shown that significant improvement in mechanical property is obtained for all reinforced nanocomposites and the addition of 1% sepiolite appears to be an optimum blend ratio. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006
Effect of ethanol on chemically synthesized polyaniline nanothread
Authors: Kan Jinqing , Zhang Shuling , Jing Guolin
Published: December 2005

The nanothread of polyaniline (PANI) using ammonium persulphate ((NH4)2S2O8) as an oxidant was prepared. The solution is composed of 0.4 mol dm−3 aniline, 1.0 mol dm−3 hydrochloric acid, and different proportions ethanol. The resulting products were characterized using infrared spectroscopy, UV–vis spectra, transmission electron microscope, thermogravimetric analysis techniques, and X‐ray diffraction. The experimental results show that the content of ethanol has effects on the morphology of PANI, but the effects on the conductivity are not very obvious. When the volume ratio of ethanol to aniline is 1:2, the more uniform and regular PANI nanothread can be prepared. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1848–1853, 2006
Effect of impregnation and in‐situ polymerization of methacrylates on hardness of sugar maple wood
Authors: Zhang Yaolin , Zhang S. Y. , Chui Ying Hei , Wan Hui
Published: December 2005

The improvement of Brinell hardness of sugar maple (Acer saccharum Marsh.) samples through impregnation and in‐situ polymerization of methyl methacrylate, 2‐hydroxylethyl methacrylate, and ethylene glycol dimethacrylate monomers was investigated. The formulation combinations were determined by a mixture design. Sugar maple samples were impregnated with these mixtures by a vacuum and pressure process and polymerized in situ by a catalyst‐thermal procedure. The effects of the monomers and their combinations on Brinell hardness and hardness modulus were analyzed. Chemical impregnation enhanced both Brinell hardness and hardness modulus. A significant relationship between hardness modulus and Brinell hardness was found. Modulus of elasticity of sugar maple was also improved through impregnation with methacrylates. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1674–1683, 2006
A rheological study on kinetics of poly(butylene terephthalate) melt intercalation
Authors: Wu Defeng , Zhou Chixing , Zheng Hong
Published: December 2005

A multilayered sample with alternatively superposed poly(butylene terephthalate) (PBT) and nonpolar polymer/clay sheets was elaborately prepared to investigate the whole hybridization process of polar polymer. The kinetics of PBT melt intercalation was studied by a rheological approach. The whole intercalation process was demonstrated by the changes of the low‐frequencies viscoelastic response with annealing time. The results of the apparent diffusivities and the calculated activation energy indicate that the PBT/clay hybrid formation presents a molecular weight dependence, which may result from the enhancement of interactions between polar groups on PBT chains and the silicate surface. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1865–1871, 2006
Structure development in amorphous starch as revealed by X‐ray scattering: Influence of the network structure and water content
Authors: Bayer R. K. , Cagiao M. E. , Calleja F. J. Baltá
Published: December 2005

The evolution of the amorphous structure of starch was characterized during the drying process by real‐time X‐ray wide‐angle scattering. The X‐ray diffractograms of injection‐molded starch show two superposed, rather broad, scattering maxima indicative of noncrystalline structures. The location of the two peaks has been associated to disordered starch single helices. A third maximum that arises upon drying the material in vacuum is associated to the scattering emerging from regions containing double helices. A model for the starch network is proposed, assuming a primary and a secondary component. The wider, temperature stable component appearing first, is correlated to the entanglement network of the melt. The narrower network component, which is created later, at lower temperature (secondary network), is explained by the formation of double helix regions that densify the wider primary network. The secondary network is increased strongly by the drying process. X‐ray experiments performed during the penetration of water, provoking a higher molecular mobility, reveal a better‐packed helical structure that becomes the precursor of a double helix crystalline formation. When temperature increases, the secondary network is dissolved and water molecules arrange themselves in better‐organized crystals as strongly bound crystal water. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1880–1886, 2006
Behavior of ionomers of sulfonated styrene–butadiene–styrene triblock copolymer in polymer blends with crystalline polyolefins and as compatibilizer
Authors: Xie Hong‐Quan , Liu Da‐Gang , Xie Dong , Guan Jian‐Guo
Published: December 2005

The blends of ionomers of sulfonated (styrene–butadiene–styrene) triblock copolymer with two polyolefins as well as the blends of polystyrene (PSt) with two polar, oil‐resistant elastomers, i.e., chlorohydrin rubber (CHR) and chlorosulfonated polyethylene (CSPE), using the ionomer as compatibilizer were studied. The blends of the ionomer with polypropylene or high density polyethylene showed synergistic effects with respect to tensile strength. With increasing PSt content, the blends change their behavior from thermoplastic elastomer to toughened plastics. The synergism is probably because of the thermoplastic interpenetrating polymer networks formed in the blend. The blends exhibited high resistance against diesel oil or toluene. When PSt was blended with CHR or CSPE using the ionomer as compatibilizer, only 2 or 3% ionomer was needed to enhance the mechanical properties of the blends. The effect is due to the ion–polar interaction of the ionomer with the polar polymer. The enhanced compatibility of the blends by the ionomer was demonstrated by DSC and Scanning electron micrograph. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1887–1894, 2006
Effect of nonsolvent coagulant on the morphology and radionuclide detection efficiency of CAYS‐impregnated polysulfone films
Authors: Lee Kune‐Woo , Seo Bum‐Kyoung , Lim Nan‐Ju , Nam Suk‐Tae , Han Myeong‐Jin
Published: December 2005

Single‐ or double‐layered porous films consisting of polysulfone (PSF) and cerium‐activated yttrium silicate (CAYS) were prepared through the phase inversion of polymeric solutions. For a single‐layered structure, a casting solution including n‐methylpyrrolidone (NMP) as a solvent was cast on a glass substrate and solidified by immersing into a nonsolvent bath. In a double‐layered structure, the bottom layer is a dense PSF film, prepared by vacuum coagulation of a methylene chloride/PSF solution. The top layer was formulated by coagulating the NMP solution, cast over the dense film, in a nonsolvent bath. The morphology and the radionuclide detection efficiency of the prepared films were significantly affected by the nonsolvent coagulants used. The water‐coagulated, double‐layered film showed a relatively clear‐cut interface between the two layers, indicating the rapid coagulation of the second layer. On the contrary, the film coagulated by isopropanol retained well‐developed sponge structures highly intertwined in the interface, associated with the delayed precipitation of the second layer. When spotted on the prepared films, radionuclides stayed mainly on the top surface of the isopropanol‐coagulated film, but went deep into the substructure of the film coagulated with water. In comparison with the mono‐layered films, the double‐layered ones improved the detection capacity of the spotted radionuclides, owing to the dense support layer. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99:1903–1909, 2006
Water sorption and diffusion behaviors in composite films of poly(ether imide) and bismaleimide
Authors: Seo Jongchul , Lee Choonkeun , Jang Wonbong , Sundar Saimani , Han Haksoo
Published: December 2005

The effect of a crosslinkable imide moiety, bismaleimide (BMI), on the water sorption properties of poly(ether imide) (PEl) was gravimetrically measured and interpreted together with the chemical and morphological structures in composite films. The morphological structure of composite films was investigated by using a prism coupler and X‐ray diffraction pattern. It indicated that the in‐plane orientation and intermolecular packing order increased as the content of BMI in composite films increased. The water sorption behaviors showed dependence on the morphological change originating from the addition of BMI to PEI. The composite film with relatively high content of BMI exhibited a relatively high degree of in‐plane orientation and a small mean intermolecular distance, which resulted in a decrease in the diffusion rate and water sorption and an increase in the activation energy in composite films. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1692–1697, 2006
Characterization of evaporated and sputtered thin Au layers on poly(ethylene terephtalate)
Authors: Švorčík V. , Slepička P. , Švorčíková J. , Špírková M. , Zehentner J. , Hnatowicz V.
Published: December 2005

Gold layers were prepared on poly(ethylene terephtalate) substrate by diode sputtering and vacuum evaporation. The mean layer thickness was determined by atomic absorption spectroscopy. Sheet electrical resistance and reflection of electromagnetic waves were used for the characterization of layers. Surface morphology of the layers was determined using atomic force and scanning electron microscopy. While the sputtering was found to proceed with two different rates, the vacuum evaporation proceeds at a constant rate. Rapid decrease of the sheet resistance was observed during sputtering, depending on the layer thickness, in contrast to vacuum evaporation. This can be due to different mechanisms of the Au deposition. According to the measured reflection of electromagnetic waves, the layers prepared by both techniques, i.e., sputtering and vacuum evaporation, are discontinuous for thicknesses below 4 nm, continuous but heterogeneous for thickness from 4 to 10 nm, and continuous and homogeneous for thickness above10 nm. The morphology of the layers prepared by vacuum evaporation does not depend on the layer thickness. Rounded clusters are observed on the surface of the evaporated layers. The layers prepared by sputtering exhibit significantly different morphology with much smaller, pointed clusters. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99:1698–1704, 2006
Comparative measurement of interfacial tension by transient dynamic methods
Authors: Son Younggon
Published: December 2005

An experimental comparison between different techniques for the interfacial tension measurement is presented for polyamide‐6 and polystyrene pair. The techniques are transient dynamic methods, which include the breaking thread (BT) method, the imbedded fiber retraction (IFR) method, the deformed drop retraction (DDR) method, and two modified DDR methods. The modified DDR methods combine the analytical power of the DDR method with experimental simplicity of the BT and IFR methods, respectively. Interfacial tension values obtained by the modified DDR method that combines the BT method is much lower than those by the other methods. Among all techniques, the modified DDR that combines the IFR method is found to be most convenient and accurate method. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99:1910–1918, 2006
Effects of aroma chemical vapor pressure and fiber morphology on the retention of aroma chemicals on cotton and poly(ethylene terephthalate) fabrics
Authors: Obendorf S. Kay , Liu Haiqing , Leonard Michael J. , Young Timothy J. , Incorvia Michael J.
Published: December 2005

Aroma chemicals with vapor pressure in the range of 10–7460 mPa were applied onto cotton and poly(ethylene terephthalate) (PET) fabrics. Retentions on these two fabric substrates were measured using gas chromatography/mass spectrometry (GC/MS), while distribution on and within fiber was graphically demonstrated by backscattered electron microscopy (BSE). Aroma chemicals with low vapor pressures were retained on the fabrics to a larger extent than aroma chemicals with higher vapor pressures. Larger amounts of aroma chemicals were retained on cotton than on PET. Effect of fiber type on retention was largest for aroma chemicals with higher vapor pressures; for example, 20% of allyl cyclohexyl propionate (1360 mPa) was retained on cotton fabric after 480 min, while none was detected on PET as compared to ambrettolide (30 mPa) that had no difference between cotton and PET after 480 min. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1720–1723, 2006
A convenient method to determine the Rayleigh ratio with uniform polystyrene oligomers
Authors: Itakura Masanao , Shimada Kayori , Matsuyama Shigetomo , Saito Takeshi , Kinugasa Shinichi
Published: December 2005

The Rayleigh ratio of toluene at 25°C for a wavelength of 632.8 nm was determined by static light scattering measurement of a certified polystyrene reference material PS 2400 with exactly evaluated or certified mass‐average molecular mass (Mw). At first, static light scattering measurements were carried out for PS 2400 in toluene with a literature value of the Rayleigh ratio of toluene. Then, corrections of degree of depolarization, density fluctuations, and molecular mass dependence of refractive index increment were applied to the observed Mw of PS 2400 to obtain apparent Mw. Finally, from the ratio between the apparent Mw and the certified Mw, the Rayleigh ratio of toluene was reevaluated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99:1953–1959, 2006
Adhesion measurement of interfaces between gelatin and poly(ethylene terephthalate) using microscratch technique
Authors: Dai Chi‐An , Liao Chih‐Chien , Tsui Tai‐An , Chien Hao‐Ching , Liu Ming‐Wei
Published: December 2005

A microscratch technique was used to evaluate the adhesion between interfaces of a gelatin coating and poly(ethylene terephthalate) (PET) film. The interface was reinforced by nitrogen plasma treatment on the PET surface and subsequently by heat treatment of each gelatin/PET sample to promote interactions at the interface. In the microscratch test, a normal load controlled conical stylus with 50‐μm radius tip was drawn over the gelatin coating surface under a continuously increasing normal load until failure occurred in the sample. Optical microscopy and depth profiling of the scratch track were used to detect failure and the failure mechanism. The critical normal load (Fc) was defined as when gelatin detached from the PET substrate or when a complete removal or plowing of the gelatin coating on the PET substrate occurred. With increasing plasma treatment time and heating treatment temperature, the Fc for both debonding and coating removal increased, which showed that both failure mechanisms are related to the adhesion. Different thicknesses of the gelatin coatings were also prepared under the same plasma and heat treatment conditions. It was found that the Fc increased with increasing coating thickness. The result demonstrated that both failure mechanisms depended on the plastic deformation of the coating and substrate. The Fc for coating detachment increased linearly with increasing coating thickness whereas the Fc for coating removal increased sharply with increasing thickness. Annealing temperatures ranging from 20 to 80°C exhibited a strong effect on the Fc, which increased with increasing annealing temperature. These results demonstrate that the microscratch technique can be used to access interfacial adhesion and that the Fc is a qualitative parameter for the evaluation of adhesion strengths. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1960–1974, 2006
Effect of molecular structure on performance of electroactive ionic acrylic copolymer–platinum composites
Authors: Jeong Han Mo , Woo Sung Min , Lee Sukmin , Cha Gook‐Chan , Mun Mu Seong
Published: December 2005

The character and performance of a new ionic polymer–metal composite (IPMC) prepared with a melt‐processable fluorinated acrylic copolymer were examined. The fluorinated acrylic copolymer was synthesized by the copolymerization of fluoroalkyl methacrylate (DuPont Zonyl) and acrylic acid, and it was compression molded to attain membranes of various thicknesses. The current and displacement responses by electric stimulus were measured to study the effects of the ionic concentration, thickness, and countercation on the actuation of the IPMC. The ionic center of the acrylic copolymer was essential for the actuation of the IPMC; however, too much ionic center induced excessive water uptake, which caused adverse effects on the performance of the IPMC. When the applied voltage was 5 V, the largest current and displacement responses were observed with the IPMC prepared by a fluorinated acrylic copolymer containing 11.8 wt % acrylic acid. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1732–1739, 2005
Novel method for preparation of quaternary ammonium ionomer from epoxidized styrene–butadiene–styrene triblock copolymer and its use as compatibilizer for blending of styrene–butadiene–styrene and chlorosulfonated polyethylene
Authors: Xie Hong‐Quan , Chen Yong , Guan Jian‐Guo , Xie Dong
Published: December 2005

A novel method for the preparation of a quaternary ammonium ionomer of styrene–butadiene–styrene triblock copolymer (SBS) was developed by a ring‐opening reaction of epoxidized SBS with triethylamine hydrochloride in the presence of a phase transfer catalyst. The optimum conditions were studied. The ionomer was characterized by quantitative analysis, IR spectroscopy, and 1H‐NMR spectroscopy. Its water absorbency, oil absorbency, dilute solution viscosity, and use as a compatibilizer for the blending of SBS and chlorosulfonated polyethylene (CSPE) were investigated. The results showed that, under optimum conditions, the epoxy groups can be completely converted to the quaternary ammonium groups. The IR spectrum did not exhibit the absorption peak for quaternary ammonium groups, whereas the 1H‐NMR spectrum and titration method demonstrated it. With increasing ionic group content, the water absorbency of the ionomer increased whereas its oil absorbency decreased. These indicated the amphiphilic character of the SBS ionomer. The dilute solution viscosity of the ionomer in toluene/methanol (9/1) solvent increased with increasing quaternary ammonium group content. The ionomer was used as a compatibilizer for the blends of SBS and CSPE. The addition of a small amount of the ionomer to the blend enhanced the mechanical properties of the blends: 2 wt % ionomer based on the blend increased the tensile strength and ultimate elongation of the blend nearly 2 times. The blends of equal parts SBS and CSPE behaved as oil‐resistant thermoplastic elastomers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1975–1980, 2006
Characterization and performance evaluations of sodium zeolite‐Y filled chitosan polymeric membrane: Effect of sodium zeolite‐Y concentration
Authors: Ahmad A. L. , Mohd Nawawi M. G. , So L. K.
Published: December 2005

Sodium zeolite‐Y (NaY zeolite) filled chitosan polymeric membranes were developed and characterized. The impact of adding different concentrations of NaY zeolite into the homogeneous chitosan membrane was investigated. The surface morphology, mechanical–physical properties, sorption, and pervaporation performance for the dehydration of isopropanol–water mixture separation by the pervaporation process were studied and evaluated. A homogeneous chitosan membrane showed preferential water sorption and permeation compared to isopropanol. The optimum concentration of NaY zeolite added to the homogeneous chitosan membrane was 0.4 wt %, which showed that the dispersion of the NaY zeolite was the most homogeneous and finely covered by the chitosan polymer in the zeolite–chitosan polymer interface. The tensile strength and percent strain at maximum of this membrane were 59.347 MPa and 27.5%, respectively. The sorption experiments showed that the degree of swelling was 6.54% with 1.01 wt % isopropanol sorbed in these membranes. The pervaporation separation tests demonstrated that the NaY zeolite filled chitosan membrane was capable for isopropanol–water mixture separation and improved the pervaporation separation index from 272 (homogeneous chitosan membrane) to 2687. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1740–1751, 2006