bluuebunny/crossref_metadata_2025 huggingface dataset:
The α‐like RNA polymerase II core subunit 3 (RPB3) is involved in tissue‐specific transcription and muscle differentiation via interaction with the myogenic factor myogenin
Authors: Corbi Nicoletta , Di Padova Monica , De Angelis Roberta , Bruno Tiziana , Libri Valentina , Iezzi Simona , Floridi Aristide , Fanciulli Maurizio , Passananti Claudio
Published: October 2002

RNA polymerase II core subunit 3 (RPB3) is an α‐like core subunit of RNA polymerase II (pol II). It is selectively down‐regulated upon treatment with doxorubicin (dox). Due to the failure of skeletal muscle cells to differentiate when exposed to dox, we hypothesized that RPB3 is involved in muscle differentiation. To this end, we have isolated human muscle RPB3interacting proteins by using yeast two‐hybrid screening. It is of interest that an interaction between RPB3 and the myogenic transcription factor myogenin was identified. This interaction involves a specific region of RPB3 protein that is not homologous to the prokaryotic α subunit. Although RPB3 contacts the basic helix‐loop‐helix (HLH) region of myogenin, it does not bind other HLH myogenic factors such as MyoD, Myf5, and MRF4. Coimmunoprecipitation experiments indicate that myogenin contacts the pol II complex and that the RPB3 subunit is responsible for this interaction. We show that RPB3 expression is regulated during muscle differentiation. Exogenous expression of RPB3 slightly promotes myogenin transactivation activity and muscle differentiation, whereas the region of RPB3 that contacts myogenin, when used as a dominant negative molecule (Sud), counteracts these effects. These results indicate for the first time that the RPB3 pol II subunit is involved in the regulation of tissue‐specific transcription.
Etomoxir‐induced increase in UCP3 supports a role of uncoupling protein 3 as a mitochondrial fatty acid anion exporter
Authors: Schrauwen Patrick , Hinderling Vera , Hesselink Matthijs K. C. , Schaart Gert , Kornips Esther , Saris Wim H. M. , Westerterp‐Plantenga Margriet , Langhans Wolfgang
Published: October 2002

The physiological function of human uncoupling protein‐3 is still unknown. Uncoupling protein‐ 3 is increased during fasting and high‐fat feeding. In these situations the availability of fatty acids to the mitochondria exceeds the capacity to metabolize fatty acids, suggesting a role for uncoupling protein‐3 in handling of non‐metabolizable fatty acids. To test the hypothesis that uncoupling protein‐3 acts as a mitochondrial exporter of non‐metabolizable fatty acids from the mitochondrial matrix, we gave human subjects Etomoxir (which blocks mitochondrial entry of fatty acids) or placebo in a cross‐over design during a 36‐h stay in a respiration chamber. Etomoxir inhibited 24‐h fat oxidation and fat oxidation during exercise by ~14–19%. Surprisingly, uncoupling protein‐3 content in human vastus lateralis muscle was markedly up‐ regulated within 36 h of Etomoxir administration. Up‐regulation of uncoupling protein‐3 was accompanied by lowered fasting blood glucose and increased translocation of glucose transporter‐4. These data support the hypothesis that the physiological function of uncoupling protein‐3 is to facilitate the outward transport of non‐metabolizable fatty acids from the mitochondrial matrix and thus prevents mitochondria from the potential deleterious effects of high fatty acid levels. In addition our data show that up‐regulation of uncoupling protein‐3 can be beneficial in the treatment of type 2 diabetes.
Korean women’s clothing brand loyalty
Authors: Oh Jungmi , Fiorito Susan S.
Published: October 2002

To be a dominant company (in other words, a long‐term successful company), it is an enormous task to build brand loyalty, to reach brand loyal customers, and to give those customers’ product satisfaction. The purpose of this study was to identify clothing brand loyal customers regarding their buying behavior, self‐image, and demographics. Also, brand loyal customers’ post‐purchase outcomes based on clothing attributes were investigated. The questionnaire was based on a self‐administrated pilot study and included measuring brand loyalty, consumer decision making, and demographics. Data were from 328 questionnaires completed by adult women living in Seoul, Korea. The results showed that in purchasing tee shirts, 24.4 percent of the sample were brand loyal customers, 42.2 percent were brand loyal customers in purchasing trousers and 38.7 percent were brand loyal customers in purchasing jackets. The multiple discriminant analysis indicated several significant variables for profiling brand loyal customers and non‐brand loyal customers. High price, brand loyal customers and low/medium price, brand loyal customers significantly differed in post‐purchase satisfaction.
Apparel involvement and advertisement processing
Authors: Kim Hye‐Shin , Lynn Damhorst Mary , Lee Kyu‐Hye
Published: October 2002

This study examines how consumer involvement with apparel influences perceptions of an apparel product (T‐shirt) presented in a print advertisement. Consumer involvement with apparel was examined in relation to three advertisement response concepts: attitude toward the advertisement, product attribute beliefs, and product attitude. Also as part of the study, three dimensions of apparel involvement were tested (fashion, comfort, and individuality). Finally, an advertising processing model that integrates apparel involvement with the three advertisement response concepts was tested. A convenience sample of students attending a midwestern university in the USA participated in data collection. Respondents were presented with a full‐page advertisement for a fictitious brand of apparel and answered items on the questionnaire. Findings confirmed that dimensions of apparel involvement shaped consumer attitudes. A combination of apparel involvement dimensions (fashion, individuality, and comfort) influenced consumer beliefs about product attributes in the advertisement. In terms of gender differences, the comfort variable showed to be a stronger component of apparel involvement for men and women tended to be more involved in fashion. Findings also supported relationships among advertisement response variables previously tested by scholars. Product attribute beliefs and ad attitude were significant in product attitude formation.
Agreeableness: Dimension of Personality or Social Desirability Artifact?
Authors: Graziano William G. , Tobin Renée M.
Published: October 2002

ABSTRACT Agreeableness is linked to socially valued traits and prosocial motives, so self‐reported Agreeableness may be distorted by self‐favoring biases (SFB). A three‐study multimethod research program explored links between the Big Five dimension of Agreeableness and SFB from three perspectives. First, we examined zero‐order relations between Agreeableness and SFB measures (N = 316). Next, we used a round robin design (N = 351) and the Social Relations Model analyses (Kenny, 1994) to partition perceptions of Agreeableness into target and perceiver effects. These effects then were related to SFB concerns, and differential responsiveness to a manipulation of the social desirability of Agreeableness. Study 3 (N = 312) examined a manipulation of Agreeableness as a moderator of the relation between dispositional Agreeableness and interpersonal conflict tactics. Overall, results indicate that Agreeableness is not easily manipulated nor distorted by SFB. Results are discussed in terms of Agreeableness as a substantive system of motives.
Recognition of DNA by Fur: a Reinterpretation of the Fur Box Consensus Sequence
Authors: Baichoo Noel , Helmann John D.
Published: October 2002

Ferric uptake repressor (Fur) proteins regulate the expression of iron homeostasis genes in response to intracellular iron levels. In general, Fur proteins bind with high affinity to a 19-bp inverted repeat sequence known as the Fur box. An alignment of 19 operator sites recognized byBacillus subtilisFur revealed a different conserved 15-bp (7-1-7) inverted repeat present twice within this 19-bp consensus sequence. We demonstrated using electrophoretic mobility shift assays that this 7-1-7 inverted repeat comprises a minimal recognition site for high-affinity binding by Fur. The resulting revised consensus sequence is remarkably similar to a related 7-1-7 inverted repeat sequence recognized by PerR, a Fur paralog. Our analysis of the affinity and stoichiometry of DNA binding byB. subtilisFur, together with a reinterpretation of previously described studies ofEscherichia coliFur, supports a model in which the 19-bp Fur box represents overlapping recognition sites for two Fur dimers bound to opposite faces of the DNA helix. The resulting recognition complex is reminiscent of that observed for the functionally related protein DtxR. Like Fur, DtxR contains a helix-turn-helix DNA-binding motif, recognizes a 19-bp inverted repeat sequence, and has a typical DNase I footprint of ∼30 bp. By envisioning a similar mode of DNA recognition for Fur, we can account for the internal symmetries noted previously within the Fur box, the tendency of Fur to extend into adjacent regions of DNA in a sequence-selective manner, and the observed patterns of DNA protection against enzymatic and chemical probes.
An ABC Transporter from
Bacillus thuringiensis
Is Essential for β-Exotoxin I Production
Authors: Espinasse Sylvain , Gohar Michel , Lereclus Didier , Sanchis Vincent
Published: October 2002

β-Exotoxin I is a nonspecific insecticidal metabolite secreted by some
Bacillus thuringiensis
strains. Several studies of
B
.
thuringiensis
strains that have lost the capacity to produce β-exotoxin I have suggested that there is a strong correlation between high levels of β-exotoxin I production and the ability to synthesize crystal proteins. In this study, we showed that a mutant strain,
B
.
thuringiensis
407-1(Cry
−
)(Pig
+
), with no crystal gene, produced considerable amounts of β-exotoxin I together with a soluble brown melanin pigment. Therefore, β-exotoxin I production can take place after a strain has lost the plasmids bearing the
cry
genes, which suggests that these curable plasmids probably contain determinants involved in the regulation of β-exotoxin I production. Using a mini-Tn
10
transposon, we constructed a library of strain 407-1(Cry
−
)(Pig
+
) mutants. We screened for nonpigmented mutants with impaired β-exotoxin I production and identified a genetic locus harboring two genes (
berA
and
berB
) essential for β-exotoxin I production. The deduced amino acid sequence of the
berA
gene displayed significant similarity to the ATP-binding domains of the DRI (drug resistance and immunity) family of ATP-binding cassette (ABC) proteins involved in drug resistance and immunity to bacteriocins and lantibiotics. The
berB
gene encodes a protein with six putative transmembrane helices, which probably constitutes the integral membrane component of the transporter. The demonstration that
berAB
is required for β-exotoxin I production and/or resistance in
B
.
thuringiensis
adds an adenine nucleotide analog to the wide range of substrates of the superfamily of ABC proteins. We suggest that
berAB
confers β-exotoxin I immunity in
B
.
thuringiensis
, through active efflux of the molecule.
Surface Diversity in
Mycoplasma agalactiae
Is Driven by Site-Specific DNA Inversions within the
vpma
Multigene Locus
Authors: Glew Michelle D. , Marenda Marc , Rosengarten Renate , Citti Christine
Published: October 2002

The ruminant pathogen
Mycoplasma agalactiae
possesses a family of abundantly expressed variable surface lipoproteins called Vpmas. Phenotypic switches between Vpma members have previously been correlated with DNA rearrangements within a locus of
vpma
genes and are proposed to play an important role in disease pathogenesis. In this study, six
vpma
genes were characterized in the
M. agalactiae
type strain PG2. All
vpma
genes clustered within an 8-kb region and shared highly conserved 5′ untranslated regions, lipoprotein signal sequences, and short N-terminal sequences. Analyses of the
vpma
loci from consecutive clonal isolates showed that
vpma
DNA rearrangements were site specific and that cleavage and strand exchange occurred within a minimal region of 21 bp located within the 5′ untranslated region of all
vpma
genes. This process controlled expression of
vpma
genes by effectively linking the open reading frame (ORF) of a silent gene to a unique active promoter sequence within the locus. An ORF (
xer1
) immediately adjacent to one end of the
vpma
locus did not undergo rearrangement and had significant homology to a distinct subset of genes belonging to the λ integrase family of site-specific
xer
recombinases. It is proposed that
xer1
codes for a site-specific recombinase that is not involved in chromosome dimer resolution but rather is responsible for the observed
vpma
-specific recombination in
M. agalactiae
.
ON THE FIXED-POINT SETS OF TORUS ACTIONS ON FLAG MANIFOLDS
Authors: SHIPMAN BARBARA A.
Published: October 2002

This paper takes a detailed look at a subject that occurs in various contexts in mathematics, the fixed-point sets of torus actions on flag manifolds, and considers it from the (perhaps nontraditional) perspective of moment maps and length functions on Weyl groups. The approach comes from earlier work of the author where it is shown that certain singular flows in the Hamiltonian system known as the Toda lattice generate the action of a group A on a flag manifold, where A is a direct product of a non-maximal torus and unipotent group. As a first step in understanding the orbits of A in connection with the Toda lattice, this paper seeks to understand the fixed points of the non-maximal tori in this setting.
PATCHING DUALITIES
Authors: ÁNH PHAM NGOC , HERBERA DOLORS
Published: October 2002

Let R anf T be rings, and let U be a faithful R-T-bimodule. We show that the triple (R, U, T) has a Morita duality if and only if RR and TT are linearly compact, and there is a duality between the semisimple factors R/J(R) and T/J(T) induced by the socle of U.

The main tool to prove this result is proving that lattice anti-isomorphisms can be patched together provided the AB-5* condition is satisfied.
An analysis of misaligned spline couplings
Authors: Medina S , Olver A. V.
Published: October 2002

The evolution of slip and pressure between the teeth of involute side-fit spline couplings subjected to a steady torque and a rotating misalignment has been studied, using the boundary integral element method.

Results show that the tooth load and pressure oscillate during shaft rotation while the teeth undergo a complex cycle of slip. Approximate formulae are provided in order to describe the pressure and wear behaviour of the coupling in terms of dimensionless parameters. The wear pattern on a spline tooth was correctly predicted.
A multi-beam intensity-based approach for lubricant film measurements in non-conformal contacts
Authors: Guo F , Wong P. L.
Published: October 2002

Studies of elastohydrodynamic lubrication (EHL) frequently utilize the phenomenon of optical interference which is exhibited when an illuminated steel ball is in contact with a partially Cr-coated glass disc in conjunction with a lubricant layer of known refractive index. The use of the steel and chromium surfaces enables lubricants having similar refractive indices to glass to be examined. The EHL contact is composed of two microscopically thin layers: the Cr coating and the lubricant film, bounded by the glass disc and the steel ball. That the two-beam interference method frequently used in optical EHL research may induce significant errors in the measurement of film thickness is reported in this paper. A theoretical analysis which includes consideration of the effects of both multi-beam interference and optical absorption within the Cr film and the steel surface is presented. The analysis is used to devise a multi-beam intensity-based test technique which has been validated for a wide range of lubricant film thickness measurements at a resolution of 1 nm and offers a practical minimum detectable film thickness as thin as 1 nm.
A study of a journal bearing lubricated by couple stress fluids considering thermal and cavitation effects
Authors: Wang X-L , Zhu K-Q , Gui C-L
Published: October 2002

A theoretical study of a finite grooved journal bearing lubricated with couple stress fluids is made considering both thermal and cavitation effects. On the basis of the Stokes couple stress fluid model, the modified Reynolds equation and the energy equation are derived and then numerically solved together with the heat conduction equation. The solution to the modified Reynolds equation is determined using the Elrod cavitation algorithm. The effects of couple stress on the performance of a journal bearing are investigated. It is observed that the lubricants with couple stress, compared with Newtonian lubricants, not only yield an obvious increase in load capacity and decrease in coefficient of friction but also produce a slight increase in the temperature of lubricants and bush and a slight decrease in the side leakage flow.
Antiaggressive Effects of Zolpidem and Zopiclone in Agonistic Encounters Between Male Mice
Authors: Martín‐López Mercedes , Navarro José Francisco
Published: October 2002

The effects of benzodiazepines on various types of aggression have been extensively studied. These substances produce their pharmacological effects by allosterically modulating the action of GABA via specific recognition sites on the GABAA receptor called omega 1 and omega 2. The antiaggressive profile of non‐benzodiazepine compounds that also act at omega sites, such as zopiclone (a non‐selective omega 1 and 2 ligand) and zolpidem (a selective omega 1 ligand) has been scarcely explored. In this study, we examined the action of zolpidem (0.75‐3 mg/kg, intraperitoneally) and zopiclone (1.5‐6 mg/kg), administered acutely or subchronically for 10 days, on agonistic behavior elicited by isolation in male mice. Individually housed mice were exposed to anosmic “standard opponents” 30 min after drug administration, and the encounters were videotaped and evaluated using an ethologically based analysis. Acute treatment with zopiclone produced a marked antiaggressive effect, reducing offensive behaviors (threat and attack) at all doses used (1.5, 3, and 6 mg/kg) without affecting immobility. Likewise, the intermediate dose of zolpidem (1.5 mg/kg) significantly decreased aggression in a specific manner, without altering immobility, whereas the highest dose (3 mg/kg) provoked a reduction of aggression accompanied by a weak (but significant) increase of immobility. With repeated treatment, no tolerance to the antiaggressive effects of zopiclone and zolpidem was developed. It is concluded that omega sites at the GABAA receptor could be involved in the control of aggression. Aggr. Behav. 28:416–425, 2002. © 2002 Wiley‐Liss, Inc.
On the design of signal sets with constrained magnitude spectrum and phase structure
Authors: Jiao Bin , Nordholm Sven , Yan Wei‐Yong , Zang Zhuquan
Published: October 2002

In this paper, a new method is introduced for designing signals that have low cross‐correlation among them with constant passband magnitude spectrum and quadratic phase. It is shown that in order to get low values of the cross‐correlation magnitude between any two signals in the set, the coefficients of the phase functions should be equally spaced along one axis of an ellipse determined by the bandwidth and time duration of signals. Furthermore, as an estimate of the maximum cross‐correlation magnitude, a new tighter upper bound is also given in the paper. Copyright © 2002 John Wiley & Sons, Ltd.
Very low dose warfarin as prophylaxis against ultrasound detected deep vein thrombosis following primary hip replacement
Authors: Bern Murray M. , Bierbaum Benjamin , Wetzner Steven , Brennan William , McAlister Sheila
Published: October 2002

One mg daily warfarin was compared to variable dose warfarin (PT 1.3–1.5 times the normal PT), as prophylaxis against deep vein thrombosis (DVT) following unilateral hip replacement for degenerative joint disease (DJD). Ninety‐eight patients entered onto study after having had negative color Doppler ultrasounds of the legs. Patients receiving 1 mg began therapy 7 days preoperatively and continued daily until discharge. Patients receiving the variable dose took 5 mg the night preoperatively, and thereafter daily based upon the daily PT. Seventy‐eight patients completed the study protocol. No patient completing the protocol had DVT or pulmonary embolus (PE). Based upon intent to treat for all registered patients, one from each group had DVT after withdrawal from study. For patients receiving 1 mg warfarin daily, PTs extended none or slightly. Therefore, 1 mg warfarin can be used to prevent postoperative DVT following elective hip surgery. Am. J. Hematol. 71:69–74, 2002. © 2002 Wiley‐Liss, Inc.
Antiphospholipid antibodies impact the protein C (PC) pathway behavior
Authors: Gennari Laura C. , Blanco Alicia N. , Alberto María Fabiana , Grosso Silvia H. , Peirano Andrea A. , Lazzari Maria A.
Published: October 2002

Antiphospholipid antibodies may interfere with the PC pathway, displaying a resistance to the activated PC (resistant phenotype). This effect was evaluated by the APCR and the ProCG systems in 36 lupus anticoagulant samples, yielding abnormal results in 47% of APCRoriginal, 17% of APCRmodified, and 22% of ProCG test. ProCG values correlated with APCRoriginal but not with APCRmodified. Most of lupus anticoagulants affecting the PC pathway showed abnormal APCRoriginal results but not abnormal ProCG values. The different behavior between both systems may be due to the heterogeneity of the antibodies or could be attributed to the fact that, in the ProCG, a PC activator is added, while the APCR employs already activated exogenous PC. Am. J. Hematol. 71:128–130, 2002. © 2002 Wiley‐Liss, Inc.
N‐ras and p53 gene mutations in Japanese patients with myeloproliferative disorders
Authors: Tsurumi Shigeharu , Nakamura Yuichi , Maki Kazuhiro , Omine Mitsuhiro , Fujita Kazuhiro , Okamura Takashi , Niho Yoshiyuki , Hashimoto Sachiko , Kanno Keiko , Suzuki Kenshi , Hangaishi Akira , Ogawa Seishi , Hirai Hisamaru , Mitani Kinuko
Published: October 2002

Alterations of the N‐ras oncogene and p53 tumor suppressor gene have been demonstrated to play an important role in pathogenesis of hematological malignancies. We simultaneously investigated genetic lesions of both genes in bone marrow cells from 64 Japanese patients with myeloproliferative disorders (MPD), including polycythemia vera (PV), essential thrombocythemia (ET), and idiopathic myelofibrosis (MF), by direct sequencing analysis. No mutations of the N‐ras gene were detected in any cases. Two patients, one with chronic neutrophilic leukemia derived from PV and one with acute mylogenous leukemia derived from ET, exhibited three mutations of the p53 gene. Among them, two were missense mutations in exon 5 or 7 and one was a deletion in exon 5. All samples in chronic phase or from MF were devoid of mutations in both genes. These data suggested that disruptions of both genes are extremely rare in MPD in chronic phase and that loss of functions in the p53 gene could be involved in progression of MPD such as PV and ET. Am. J. Hematol. 71:131–133, 2002. © 2002 Wiley‐Liss, Inc.
Self‐reported hand and wrist arthritis and occupation: Data from the U.S. National Health Interview Survey–Occupational Health Supplement
Authors: Dillon Charles , Petersen Martin , Tanaka Shiro
Published: October 2002

Background

There is a paucity of population‐based studies examining occupational hand‐wrist arthritis. We examined relationships between hand‐wrist arthritis, occupation, and biomechanical exposures in the U.S. National Health Interview Survey–Occupational Health Supplement.

Methods

A randomized, multi‐stage, and cross‐sectional national prevalence survey was carried out.

Results

Self‐reported, medically attended hand‐wrist arthritis was common among employed persons (period prevalence 1.58%; lifetime prevalence 3.58%). Highest prevalences occurred among technicians, machine operators, assemblers, and farmers, and in the mining, agriculture, and construction industries. Work requiring repetitive hand bending and twisting was associated with hand‐wrist arthritis (Odds Ratio 1.43; 95%CI: 1.11–1.84; P = 0.005). Among workers with hand arthritis, 7.4% had made major changes in their work, 7.6% missed work, and 4.5% stopped working or changed jobs because of the problem.

Conclusions

Our study links hand‐wrist arthritis to occupation and potentially modifiable workplace ergonomic factors. The spectrum of hand‐wrist “cumulative trauma” disorders may considerably exceed that of soft‐tissue injuries like carpal tunnel syndrome and tendonitis, and may include arthritis, a widely prevalent, disabling condition. Am. J. Ind. Med. 42: 318–327, 2002. © 2002 Wiley‐Liss, Inc.
Noise exposure and hearing conservation practices in an industry with high incidence of workers' compensation claims for hearing loss
Authors: Daniell William E. , Swan Susan S. , McDaniel Mary M. , Stebbins John G. , Seixas Noah S. , Morgan Michael S.
Published: October 2002

Background

Washington State has experienced a striking increase in workers' compensation claims for hearing loss.

Methods

This cross‐sectional study examined noise exposures and hearing conservation practices in one industry with a high rate of hearing loss claims. We evaluated 10 representative foundries with personal noise dosimetry, management interviews, employee interviews, and existing audiometry.

Results

Noise levels routinely exceeded 85 dBA. All companies were out of compliance with hearing conservation regulations. Most employees with important findings on audiograms were not aware of their findings. There was a significant positive correlation between management‐interview scores and worksite‐average employee‐interview scores (r = 0.70, P = 0.02).

Conclusions

Companies where more effort is put into hearing conservation program activities can achieve a greater positive impact on employee awareness. However, there were broad deficiencies even in the better programs in this sample, suggesting that workers in this industry probably face a continuing substantial risk of occupational hearing loss. Am. J. Ind. Med. 42:309–317, 2002. © 2002 Wiley‐Liss, Inc.
CFC index for the diagnosis of cardiofaciocutaneous syndrome
Authors: Kavamura M.I. , Peres C.A. , Alchorne M.M.A. , Brunoni D.
Published: October 2002

Controversy exists concerning the delineation of cardiofaciocutaneous syndrome (CFC). Many authors have attempted to establish syndrome traits for CFC, but to date none are pathognomonic or obligatory. We have created a clinical and objective method, called the CFC index, for CFC diagnosis. This method also differentiates CFC from Noonan syndrome and Costello syndrome, CFC's main differential diagnosis. We propose the use of the CFC index for the confirmation of CFC diagnosis and to differentiate CFC from other phenotypically similar genetic conditions, while molecular studies are still in progress. © 2002 Wiley‐Liss, Inc.
Classification trees as an alternative to linear discriminant analysis
Authors: Feldesman Marc R.
Published: October 2002

Linear discriminant analysis (LDA) is frequently used for classification/prediction problems in physical anthropology, but it is unusual to find examples where researchers consider the statistical limitations and assumptions required for this technique. In these instances, it is difficult to know whether the predictions are reliable. This paper considers a nonparametric alternative to predictive LDA: binary, recursive (or classification) trees. This approach has the advantage that data transformation is unnecessary, cases with missing predictor variables do not require special treatment, prediction success is not dependent on data meeting normality conditions or covariance homogeneity, and variable selection is intrinsic to the methodology. Here I compare the efficacy of classification trees with LDA, using typical morphometric data. With data from modern hominoids, the results show that both techniques perform nearly equally. With complete data sets, LDA may be a better choice, as is shown in this example, but with missing observations, classification trees perform outstandingly well, whereas commercial discriminant analysis programs do not predict classifications for cases with incompletely measured predictor variables and generally are not designed to address the problem of missing data. Testing of data prior to analysis is necessary, and classification trees are recommended either as a replacement for LDA or as a supplement whenever data do not meet relevant assumptions. It is highly recommended as an alternative to LDA whenever the data set contains important cases with missing predictor variables. Am J Phys Anthropol 119:257–275, 2002. © 2002 Wiley‐Liss, Inc.
Preparation and characterization of the copolymer containing N‐pyridyl bi(methacryl)imide unit
Authors: Li Xin‐Gui , Huang Mei‐Rong , Shao Hong‐Tao
Published: October 2002

The copolymer of methacrylic acid anhydride and N‐2‐pyridyl bi(methacryl)imide was prepared based on the reaction of polymethacrylic acid with 2‐pyridylamine. The molecular structure was characterized by 1H‐NMR, FTIR, UV–Vis, and circular dichroism techniques. The physical properties of polymethacrylic acid change significantly after an introduction of 6 mol % N‐2‐pyridyl bi(methacryl)imide unit. In particular, the thermal degradation of the polymer was systematically studied in flowing nitrogen and air from room temperature to 800°C by thermogravimetry at a constant heating rate of 10°C/min. In both atmospheres, a four‐stage degradation process of the copolymer of methacrylic acid anhydride and N‐2‐pyridyl bi(methacryl)imide was revealed. The initial thermal degradation temperature Td, and the first, second, and third temperatures at the maximum weight‐loss rate Tdm1, Tdm2, and Tdm3 all decrease with decreasing sample size or changing testing atmosphere from nitrogen to air, but the fourth temperature at the maximum weight‐loss rate Tdm4 increases. The maximum weight‐loss rate, char yield at elevated temperature, four‐stage decomposition process, and three kinetic parameters of the thermal degradation were discussed in detail. It is suggested that the copolymer of methacrylic acid anhydride and N‐2‐pyridyl bi(methacryl)imide exhibits low thermal stability and multistage degradation characteristics. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1673–1678, 2002
Thermal and crystallization characteristics of poly(ethylene terephthalate) with poly(oxybenzoate‐p‐trimethylene terephthalate) copolymer
Authors: Ou Cheng‐Fang , Li Wang Cheng , Chen Yu Hsien
Published: October 2002

Poly(ethylene terephthalate) (PET) was blended with two different poly(oxybenzoate‐p‐trimethylene terephthalate) copolymers, designated T28 and T64, with the level of copolymer varying from 1 to 15 wt %. All samples were prepared by solution blending in a 60/40 (by weight) phenol/tetrachloroethane solvent at 50°C. The crystallization behavior of the samples was studied by DSC. The results indicate that both T28 and T64 accelerated the crystallization rate of PET in a manner similar to that of a nucleating agent. The acceleration of PET crystallization rate was most pronounced in the PET/T64 blends with a maximum level at 5 wt % of T64. The melting temperatures for the blends are comparable to that of pure PET. The observed changes in crystallization behavior are explained by the effect of the physical state of the copolyester during PET crystallization as well as the amount of copolymer in the blends. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1599–1606, 2002
Photo‐induced emulsion polymerization of vinyl acetate in the presence of poly(oxyethylene) nonyl phenyl ether, a nonionic emulsifier (II)
Authors: Mah Soukil , Lee Dongeun , Koo Donghun , Kwon Soonhong
Published: October 2002

Synthesis of high molecular weight poly(vinyl acetate) having less branched structure via photo‐induced emulsion polymerization of vinyl acetate in the presence of poly(oxyethylene)20 nonyl phenyl ether, a nonionic emulsifier, was attempted at 0°C or even below 0°C in the presence of methanol. It was found that 100% conversion is always achieved in all runs and poly(vinyl acetate) having the number‐average degree of polymerization of 9000 with less branched structure (degree of branch < 0.5) can be obtained from this photo‐induced emulsion polymerization system. Mechanisms of the polymerization were also discussed on the basis of the kinetic results. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2153–2158, 2002
The effect of TIBA on metallocene/MAO catalyzed synthesis of propylene oxazoline copolymers and their use in reactive blending
Authors: Kaya Atila , Pompe Gisela , Schulze Ulrich , Voit Brigitte , Pionteck Jürgen
Published: October 2002

Oxazoline‐functionalized polypropylenes were synthesized by using the rac‐Et[1‐Ind]2ZrCl2/MAO catalyst system. The used comonomers were 2‐(9‐decene‐1‐yl)‐1,3‐oxazoline (R‐Ox1), 2‐(9‐decene‐1‐yl)‐4,4‐dimethyl‐1,3‐oxazoline (R‐Ox2), and 2‐(4‐(10‐undecene‐1‐oxy)phenyl)‐1,3‐oxazoline (R‐Ox3). The oxazolines reduce the catalyst activity in the order R‐Ox3 > R‐Ox1 > R‐Ox2. By the addition of triisobutylaluminum (TIBA), the catalyst poisoning is reduced and is most pronounced in the R‐Ox1‐ and R‐Ox2‐containing systems. The oxazoline‐containing copolymers were melt blended with carboxylic acid end‐functionalized polystyrene (PS‐COOH) at 200°C. Strong changes in the morphology of the reactive blends compared to the nonreactive blends, especially the cocontinuous morphology in a poly(propylene‐co‐R‐Ox3)/PS‐COOH blend, indicate the usefulness of the modified copolymers in the reactive blending processes. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2174–2181, 2002
Effect of isomerization on the stability of the surface aggregation structure of chlorinated polyacrylamide thin films on the basis of interferometric observations
Authors: Shehata A. B. , Amer M.
Published: October 2002

Three isomers of chlorinated polyacrylamides were synthesized by a solution polymerization technique. The prepared polymers were dissolved in acetone to prepare 0.1 and 0.05 wt % solution concentrations. Polymer thin films were then prepared by spin‐casting from acetone solutions onto a glass substrate. The prepared films were characterized by Fourier transform infrared (FTIR) spectroscopy and annealed at 80°C for 6 h. The surface morphology of the prepared films was studied before and after annealing with an interference microscope to determine the effect of isomerization on the stability of the polymer thin films. The thin film of the polymer with a chlorine atom in the para‐position showed better stability due to the ionic interaction with the glass substrate. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2601–2606, 2002
Polymerization and characterization of bis(trichlorophenolato)di(pyridine) nickel(II) and bis(tribromophenolato)di(pyridine) nickel(II) dihydrate complexes in solution in the presence of iodine
Authors: Molu L. (Karabey) , Kısakürek D.
Published: October 2002

The syntheses of bis(trihalophenolato)di(pyridine) nickel(II) complexes were achieved in aqueous solution, and their characterizations were performed by Fourier transform infrared (FTIR) spectroscopy, ultraviolet‐visible analysis, differential scanning calorimetry, and elemental analysis. The thermal polymerization of these complexes was studied in toluene solution in the presence of iodine. The effect of time, temperature, and amount of iodine added on the percentage conversion, structure of polymers, and intrinsic viscosity ([η]) were investigated. Polymers were characterized by FTIR, 1H‐NMR, and 13C‐NMR spectroscopic analyses, glass‐transition temperatures determined by differential thermal analysis, and [η] values determined by the viscometric method. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2232–2239, 2002
Microwave‐assisted synthesis of new optically active poly(ester‐imide)s containing N,N′‐(pyromellitoyl)‐bis‐L‐phenylalanine moieties
Authors: Mallakpour Shadpour E. , Hajipour Abdol‐Reza , Habibi Sakineh
Published: October 2002

Pyromellitic dianhydride (benzene‐1,2,4,5‐tetracarboxylic dianhydride) (1) was reacted with L‐phenylalanine (2) in a mixture of acetic acid and pyridine (3 : 2) and the resulting imide‐acid [N,N′‐(pyromellitoyl)‐bis‐L‐phenylalanine diacid] (4) was obtained in quantitative yield. The compound (4) was converted to the N,N′‐(pyromellitoyl)‐bis‐L‐phenylalanine diacid chloride (5) by reaction with thionyl chloride. A new facile and rapid polycondensation reaction of this diacid chloride (5) with several aromatic diols such as phenol phthalein (6a), bisphenol‐A (6b), 4,4′‐hydroquinone (6c), 1,8‐dihydroxyanthraquinone (6d), 4,4‐dihydroxy biphenyl (6e), and 2,4‐dihydroxyacetophenone (6f) was developed by using a domestic microwave oven in the presence of a small amount of a polar organic medium such as o‐cresol. The polymerization reactions proceeded rapidly and are completed within 20 min, producing a series of optically active poly(ester‐imide)s with good yield and moderate inherent viscosity of 0.10–0.26 dL/g. All of the above polymers were fully characterized by IR, elemental analyses, and specific rotation. Some structural characterization and physical properties of these optically active poly(ester‐imide)s are reported. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2211–2216, 2002
Novel fixed‐carrier membranes for CO2 separation
Authors: Zhang Ying , Wang Zhi , Wang Shichang
Published: October 2002

A new membrane material having two kinds of CO2 carriers was obtained. Composite membranes were prepared with the material and support membranes. The facilitated transport of CO2 through these membranes was performed with pure CH4 and CO2 as well as CH4/CO2 mixtures containing 50 vol % CO2. The results show that the membranes possess better CO2 permeance than that of other fixed carrier membranes reported in the literature. In the measurements with pure gases, at 26°C, 0.013 atm of CO2 pressure, the membrane with polysulfone support displays a CO2 permeance of 7.93 × 10−4 cm3 /cm2 s cmHg and CO2/CH4 ideal selectivity of 212.1. In the measurements with mixed gases, at 26°C, 0.016 atm of CO2 partial pressure, the membrane displays a CO2 permeance of 1.69 × 10−4 cm3 /cm2 s cmHg and CO2/CH4 selectivity of 48.1. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2222–2226, 2002
Preparation and characterization of cation‐exchange media based on flexible polyurethane foams
Authors: Yeon Kyeong‐Ho , Lee Jin‐Woo , Lee Jae‐Suk , Moon Seung‐Hyeon
Published: October 2002

Continuous electrodeionization (CEDI) is used to deionize a solution to a level attained by mixed bed ion exchange without chemical regeneration. However, handling of ion‐exchange beads is laborious for a large‐scale CEDI system. In this study, a new type of ion‐exchange polyurethane foam containing sulfonic acid groups was synthesized by bulk condensation polymerization for use as a cation‐exchange medium. Polyurethanes are synthesized by the reaction between a diisocyanate and a polyol. Toluene diisocyanate 2,4‐80%, 2,6‐20% (http://www.tciamerica.com/) was reacted with poly(propylene glycol) to synthesize a polyurethane prepolymer and then N,N‐bis(2‐hydroxylethyl)‐2‐aminoethanesulfonic acid (BES) was added to give a foam containing sulfonic acid groups. The functional polyurethane prepolymers were characterized by proton nuclear magnetic resonance spectroscopy (1H NMR), Fourier transform infrared spectroscopy (FT‐IR), elemental analysis (EA), and gel permeation chromatography (GPC). The ion‐exchange capacity was measured as 2.5 meq/g, and the equiconductance point of the polyurethane foams were 14, 19, 29, and 33 μ/cm for BES molar ratios of 0.5, 0.7, 1.0, and 1.5, respectively. The porous plug model shows that the current flows dominantly through the solution phase of the polyurethane foam, which indicates the polyurethane foam is a suitable medium for use in a CEDI operation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1773–1781, 2002
Effect of the tacticity of poly(methyl methacrylate) on the phase diagram of its ternary blends
Authors: Hsu Wen‐Ping
Published: October 2002

Previously, isotactic and atactic poly(methyl methacrylates) (PMMAs) were found to be miscible with poly(vinyl phenol) (PVPh) and poly(hydroxy ether of bisphenol‐A) (phenoxy) because all the prepared films were transparent and showed composition‐dependent glass transition temperatures (Tg's). However, syndiotactic PMMA was immiscible with PVPh because most of the cast films had two Tg's. On the contrary, syndiotactic PMMA was still miscible with phenoxy. According to our preliminary results, PVPh and phenoxy are not miscible. Also to our knowledge, nobody has reported any results concerning the effect of the tacticity of PMMA on its ternary blend containing PVPh and phenoxy. The miscibility of a ternary blend consisting of PVPh, phenoxy, and tactic PMMA was thus investigated and reported in this article. Calorimetry was used as the principal tool to study miscibility. An approximate phase diagram of the ternary blends containing different tactic PMMA was established, probably for the first time, based on differential scanning calorimetry data. Immiscibility was found in most of the studied ternaries but a slight difference due to the effect of tacticity of PMMA was definitely observed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2720–2726, 2002
Synthesis and flocculation properties of N‐oxide polymers
Authors: Anleu E. , Cardoso J. , Manero O.
Published: October 2002

N‐oxide polymers possess strong zwitterionic character, high solubility in water, and high chelating properties with various cations. In this work, N‐oxide polymers were synthesized following various routes and their solution properties were determined. Molecular properties of the polymers (molecular weight, square root of the mean‐squared radius, and virial coefficients) were related to their chain expansion in solution by determining the intrinsic viscosity as a function of pH. Viscosity results were correlated with the flocculation ability of the polymers for suspending solids removal. These polymers exhibit dramatic conformation changes as the solution pH is varied, especially at low pH values. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2693–2700, 2002
Polymer microspheres with surface chains prepared by dispersion copolymerization using poly(oxyethylene) macromonomer
Authors: Wang P. H. , Pan Cai‐Yuan
Published: October 2002

Polymer microspheres were prepared by dispersion copolymerization of styrene with poly(oxyethylene) (peo) macromonomer. A dispersion terpolymerization of styrene, PEO macromonomer and acrylic acid was also conducted to prepare polymer microspheres with both surface carboxyl groups and PEO polymer chains. The microspheres thus obtained were characterized with TEM, IR, and X‐ray photoelectron spectroscopy analyses. Palladium nanoparticles were then formed on the surface of these copolymer microspheres forming polymer/metal nanocomposites which were then studied by TEM and X‐ray diffraction. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2732–2736, 2002
Strengthening due to interlamellar constraint in oriented syndiotactic styrene–p‐methyl styrene copolymer
Authors: Pricope D. , Shinozaki D. M.
Published: October 2002

Channel die compression has been used to form highly oriented syndiotactic styrene–p‐methylstyrene copolymer in the solid state. The highest forming temperatures were at or near the nominal unoriented melting point (247°C). The oriented materials produced at 245 and 220°C were examined by differential scanning calorimetry, wide‐angle X‐ray diffraction, and dynamic mechanical thermal analysis. The measured increases in modulus, which resulted from the forming of the copolymer could be related to the microstructural changes in the material. The analysis of mechanical properties with a simple Takayanagi model showed that the high modulus above the glass transition temperature in oriented samples was at least partly due to an interlamellar constraint of the kind suggested by Arridge and co‐workers. The magnitudes of the constraint factor that were estimated in the modeling process were consistent with the observed microstructural changes. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2312–2321, 2002
Continuous emulsion polymerization of vinyl acetate. I. Operation in a single continuous stirred tank reactor using sodium lauryl sulfate as emulsifier
Authors: Nomura M. , Sasaki S. , Xue W. , Fujita K.
Published: October 2002

Continuous emulsion polymerizations of vinyl acetate were carried out at 50 °C in a single continuous stirred‐tank reactor using sodium lauryl sulfate as emulsifier and potassium persulfate as initiator. It was found that (1) the so‐called limit cycles could take place in monomer conversion, the number of polymer particles and the molecular weight of polymers produced under certain operating conditions, (2) the time‐average steady‐state monomer conversion was proportional to the 0.31 power of the emulsifier concentration in the feed, to the 0.50 power of the initiator concentration, to the −1.0 power of the monomer concentration, and to the 0.90 power of the mean residence time, and (3) the time‐average steady‐state number of polymer particles produced was proportional to the 2.1 power of the emulsifier concentration in the feed, to the −0.80 power of the initiator concentration, to the 0 power of the monomer concentration, and to the −0.92 power of mean residence time. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2748–2754, 2002
Effect of glycerin on structure transition of PVA/SF blends
Authors: Dai Lixing , Li Jun , Yamada Eisuke
Published: October 2002

Blend films of silk fibrion (SF) and poly(vinyl alcohol) (PVA), with glycerin as an additive, were made, and the structure and properties of the blends were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FT‐IR) spectroscopy, differential scanning calorimetry (DSC), and wide‐angle X‐ray diffraction (WAXD) and with an Instron Material Tester. The results showed that SF and PVA are principally incompatible and the blends made by the two polymers were phase‐separated. The results, however, also demonstrated that the blend structure could be changed to some extent by addition of 3–8% glycerin. The boundary of the PVA and SF phases became indistinct, as reported by SEM, a new peak appeared in the WAXD curves, the width of the OH absorption peak in the FT‐IR spectra increased, and the melting points changed in the DSC curves. In particular, the mechanical properties obviously increased, from 350 kg/cm2 and 10% of PVA/SF (80/20) film to 832 kg/cm2 and 39% of PVA/SF (80/20) film because of the increase in glycerin. It was suggested that glycerin plays a role in building the relationship between PVA and SF, strengthening the interaction between them and improving their compatibility. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2342–2347, 2002