bluuebunny/crossref_metadata_2025_split huggingface dataset:
Late Pleistocene human femoral diaphyseal curvature
Authors: Shackelford Laura L. , Trinkaus Erik 
Published: September 2002

AbstractAnterior femoral curvature is a consistent characteristic of Pleistocene and recent humans, although variation exists in the degree of curvature among individuals and across populations. In particular, one group, the Neandertals, has been characterized for a century as having marked femoral curvature. To evaluate the degree of anterior femoral curvature in both Neandertals and other Late Pleistocene humans, their curvature subtenses and proximodistal positions were evaluated in the context of recent human variation. Recent human comparisons show little relationship between subtense (absolute curvature) and femoral length, suggesting that an index that incorporates subtense relative to the length of the femur is inappropriate for between‐group assessments. Neandertals were statistically indistinguishable from Middle or earlier Upper Paleolithic modern humans in the degree of absolute curvature, all of whom had greater curvature on average than all later humans. Additionally, Neandertals and Qafzeh‐Skhul early modern humans had a more distal point of maximum curvature than any other group. Curvature was not strongly correlated with functional considerations including body mass estimates, surrogate variables for body size, proximal femoral articular orientation, or knee anteroposterior dimensions. The functional role of femoral anterior curvature is unknown; however, the general decrease in curvature subtense closely parallels the between‐group changes in inferred levels of mobility from femoral diaphyseal robusticity and shape, suggesting that femoral curvature may reflect mobility levels and patterns among Late Pleistocene and recent humans. Am J Phys Anthropol 118:359–370, 2002. © 2002 Wiley‐Liss, Inc.
Scoring system for estimating age in the foot skeleton
Authors: Whitaker Jeffrey M. , Rousseau Leslie , Williams Trevor , Rowan Reed A. , Hartwig Walter Carl 
Published: September 2002

AbstractThis study assesses chronological age of immature individuals from the degree of ossification evident in the foot skeleton. We considered all tarsal and ray bones in various combinations to determine the most sensitive indicators of chronological age. Skeletal maturity was rated according to a subjective but simple scoring system applied to radiographs of normal feet of children of known chronological age. Scales for assessing the primary center of ossification, secondary center of ossification, and state of fusion are defined. In general, as expected, females show earlier onset of skeletal maturity than males; in particular, females in our sample are skeletally mature in most elements beginning 48 months prior to the earliest incidence of skeletal maturity in males for the same bones. Females in our sample show a marked tendency toward skeletal maturity of all elements by 150 months of age, while males do not show the same tendency until approximately 200 months of age. In general within each sex, consecutive states of fusion show broad overlap in range of chronological age within each bone. Combining scores from several different bones enables a reasonable estimate of potential age in a test application of the model. Am J Phys Anthropol 118:385–392, 2002. © 2002 Wiley‐Liss, Inc.
Addition of Me3SiCN to trifluoromethyl derivates of N‐(pyridylmethylidene) anilines catalyzed by Lewis acids
Authors: Iovel Irina , Golomba Lena , Belyakov Sergey , Kemme Andrejs , Lukevics Edmunds 
Published: September 2002

AbstractA series of novel Shiff bases (1a–h) was synthesized by condensation of pyridinecarboxaldehydes (1–4) with 3‐ and 4‐trifluoromethylanilines (5, 6) in the presence of molecular sieves (4 Å). It was found that AlCl3 and AlBr3 catalyzed the addition of Me3SiCN to the CN bond of the imines obtained, whereas the other Lewis acids studied (YCl3, LaCl3, ZnI2) were not active. The reactivity of the imines in the title reaction, on the whole, correlated with their basicity. Besides the addition giving the expected α‐amino nitriles (2a,b,d–f,h), an unusual reaction leading to unsaturated nitriles (3a–h) was observed. The structures of saturated and unsaturated products 2d and 3c were determined by X‐ray diffraction. Copyright © 2001 John Wiley & Sons, Ltd.
Degradation of triphenyltin compounds in sea water by pyoverdins from Pseudomonas chlororaphis
Authors: Yamaoka Yukiho , Inoue Hiroyuki , Takimura Osamu , Oota Sinji 
Published: September 2002

AbstractThe yellow compound species pyoverdin was isolated from Pseudomonas chlororaphis. Degradation of triphenyltin (TPT) by pyoverdin (20 mg) was carried in distilled water (30 ml) containing a 6 µg l−1 concentration of TPT at 20 °C for 96 h in aerobic conditions. The organotins in water and sea water were analyzed by gas chromatograph–mass spectrometry in selected ion mode. TPT and diphenyltin (DPT) in sea water were degraded to monophenyltin (MPT) with pyoverdins isolated from P. ­chlororaphis. Degradation of TPT in sea water increased with increasing temperature between 4 and 37 °C. Optimum degradation of TPT in sea water was at pH 7–8.5. Degradation of TPT and DPT in distilled water can be faster than in sea water. Also, degradation of TPT in both water and sea water was faster than that of DPT. Tributyltin, dibutyltin, monobutyltin and MPT in water and sea water were not degraded by pyoverdins isolated from P. chlororaphis. Copyright © 2001 John Wiley & Sons, Ltd.
Maternal transfer of arsenic to eggs of black‐tailed gull (Larus crassirostris) from Rishiri Island, Japan
Authors: Kubota Reiji , Kunito Takashi , Tanabe Shinsuke , Ogi Haruo , Shibata Yasuyuki 
Published: September 2002

AbstractConcentrations of total arsenic and individual arsenic compounds were determined in several tissues and eggs of the black‐tailed gull (Larus crassirostris) to characterize accumulation and maternal transfer to eggs. A relatively high concentration of arsenic was observed in the liver, kidney, pancreas, muscle and gonad. The transfer rate of arsenic to eggs of the black‐tailed gull was about 10%. Chemical speciation analysis revealed that arsenobetaine was the major arsenic compound in all the tissues. Dimethylarsinic acid, methylarsonic acid, arsenocholine, and an unidentified arsenic compound were also detected as minor constituents. Like maternal tissues, egg also contained arsenobetaine as the major arsenic compound and dimethylarsinic acid as a minor compound. These results suggest that arsenobetaine and dimethylarsinic acid can transfer from the mother bird to the eggs. To our knowledge, this is the first report on the maternal transfer of arsenic species to eggs of seabirds. Copyright © 2002 John Wiley & Sons, Ltd.
Dimethylarsinic acid causes inhibition of microtubule assembly and inhibition of calcium‐sensitive disassembly of microtubules via interaction with glutathione
Authors: Ochi Takafumi , Meguro Shiori , Namikoshi Michio , Oya‐Ohta Yukiko , Kaise Tosikazu 
Published: September 2002

AbstractThe effects of dimethylarsinic acid (DMAA) on microtubule assembly in vitro were investigated in terms of the role of glutathione (GSH). Increase in turbidity due to assembly of brain tubulins was monitored in the presence or absence of DMAA. DMAA at concentrations up to 10 mM did not cause inhibition of the increased turbidity. GSH at concentrations over 10 mM enhanced the increase in turbidity. By contrast, the increased turbidity was inhibited markedly when DMAA and GSH were combined in the ratio of 5:1. Moreover, the combination similarly inhibited calcium‐induced disassembly of microtubules with a potency equivalent to that of 10 µM taxol. These results suggest that DMAA inhibited not only microtubule assembly, but also calcium‐sensitive disassembly of microtubules, via interaction with GSH. Copyright © 2002 John Wiley & Sons, Ltd.
Short Communucation: An arsenosugar as the major extractable arsenical in the earthworm Lumbricus terrestris
Authors: Geiszinger Anita E. , Goessler Walter , Kosmus Walter 
Published: September 2002

AbstractEarthworms (Lumbricus terrestris) were investigated for arsenic compounds by high‐performance liquid chromatography inductively coupled plasma mass spectrometry MS. Total arsenic concentrations were 6.3 ± 0.4 mg kg−1 in the earthworms and 28.1 ± 1.9 mg kg−1 in the casts of the earthworms. Extraction of the samples removed ∼25% of total arsenic from the earthworm tissues, but only ∼0.7% from the casts. The major arsenic compound in the earthworm extracts was an arsenic‐containing carbohydrate (phosphate arsenosugar, ∼55%); glycerol arsenosugar, dimethylarsinic acid, methylarsonic acid, arsenate, and arsenite were also present as minor constituents. In the cast extracts, the two arsenosugars could also be detected in addition to some arsenate and arsenite. The identification of the phosphate arsenosugar was confirmed with liquid chromatography– electrospray‐mass spectrometry with detection of m/z 75 (As+) and m/z 483 [(M + H)]+; the data were identical with those recorded for authentic standard material. This is the first report of an arsenosugar as the major extractable arsenical in a terrestrial animal. Copyright © 2002 John Wiley & Sons, Ltd.
Utilization of some oligomers based on poly(ethylene terephthalate) wastes as modifiers for polyvinyl chloride
Authors: Mansour S. H. , Abd‐El‐Messieh S. L. , Ikladious N. E. 
Published: September 2002

AbstractTwo glycolyzed products, PET‐TEG and PET‐BD, were prepared by depolymerization of PET wastes using 30 wt % triethylene glycol (TEG) and 40 wt % 1,4‐butanediol (BD). In this work we investigated how the mechanical and electrical properties of PVC and PVC/EPDM blend were affected by mixing them with different concentrations of the two obtained glycolyzed products. Dynamic mechanical, DSC, and dielectric behaviors of PVC containing various amounts of the two modifiers were studied. The present data confirm that the α‐relaxation dynamic of PVC at constant frequency shifts to a lower temperature with increasing modifier content. PVC samples containing 5 phr of the two modifiers show the highest impact strength at −30°C. It was noted that addition of PET‐TEG to PVC or PVC/EPDM blend led to end products with enhanced insulating properties, which makes them suitable for industrial applications. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2501–2509, 2002
Robust on‐line measurement of conversion and molecular weight using NIR spectroscopy during solution polymerization
Authors: Cherfi A. , Fevotte G. , Novat C. 
Published: September 2002

AbstractFiber‐optic near‐infrared (NIR) spectroscopy was used to monitor the monomer conversion and the weight‐average molecular weight of the polymer produced during solution polymerization of methyl methacrylate (MMA) carried out in a lab‐scale reactor. NIR spectra were recorded during batch and semi‐continuous reactions using an in situ transmission probe. Off‐line gravimetry and GPC were used as reference methods to provide the conversion and the average molecular weight data set required for the calibration procedure. A statistical model was generated using partial least‐squares regression (PLS) to relate the NIR spectral data to the two polymerization variables of interest. The measurements were then validated for various operating conditions (i.e., different solvent, initiator, MMA, and chain‐transfer agent concentrations) and for both batch and semi‐continuous modes. The conversion was predicted during three validation experiments with an average standard error of prediction (SEP) of 2.1%. The on‐line evaluation of M̄w was obtained with an average relative SEP of 5.7%; such on‐line NIR measurement was thus demonstrated to be robust and accurate, even in the case of versatile use of the polymerization plant. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2510–2520, 2002
Acrylonitrile–maleic anhydride copolymer membranes with different molecular weights
Authors: Pei Zhi‐Chao , Pei Yu‐Xin , Wang Qing‐Rui 
Published: September 2002

AbstractThe structure and performance of acrylonitrile–maleic anhydride copolymer membranes with different molecular weights were investigated. The results showed that the water flux of the membrane decreased gradually with increasing molecular weight of the copolymer; the rejection increased only when there was an obvious increase of molecular weight. The addition of an additive (polyvinylpyrrolidone) largely decreased the water flux and rejection of the membrane when the concentration of the copolymer remained unchanged. The higher the molecular weight, the thicker were the transition layer and the wall of the support pore and the better was the anticompactness of the membrane. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2521–2527, 2002
Interaction between unlike macromolecules: A new method based on the motional resistance response of a piezoelectric quartz crystal
Authors: Mao Youan , Wei Wanzhi , Zhang Jinzhong 
Published: September 2002

AbstractA new method for the study of the interaction between unlike macromolecules was developed, based on the motional resistance (Rm) response of a piezoelectric quartz crystal sensor to viscosity change in a contacting dilute polymer solution. The experimental setup, constructed with a 9‐MHz AT‐cut quartz crystal, a flowthrough detection cell, and an impedance analyzer, was shown to provide highly reproducible data at 25°C and a fluid flow rate of 1.3–1.6 mL/min. A quantitative relationship between Rm and the relative viscosity of the dilute polymer solution was derived. A model for using Rm to study the interaction was proposed. The interaction between polyethylene glycol (PEG) and poly(vinyl alcohol) (PVAL) was studied by this method with a thermodynamic parameter α. Experimental results indicated that the values of α for the blend PEG/PVAL were 0.094 and 0.086, corresponding to molecular weights of PEG of 10,000 and 20,000, respectively, and in agreement with those of capillary viscometry. The positive value of α showed that an attractive interaction existed between PEG and PVAL. An important feature of the new method was that it could be used in continuous measurement. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2528–2534, 2002
Thermal degradation of cellulose‐based complex material
Authors: Ou Yifang , Huang Qiulian 
Published: September 2002

AbstractThermal degradation of cellulose‐based complex material was investigated by treating at 100, 140, and 160°C, respectively. The performance changes of the material such as average degree of polymerization (DP), weight loss, brightness, and tensile strength were tested during the thermal treatment. And the thermal analyses of the material was conducted to show the change in different heating stage from 27 to 700°C. The effect of anti water and anti oil agents in the complex material on the change of performances was investigated. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2535–2539, 2002
Synthesis and characterization of novel magnetic polymer microspheres with photoconductivity
Authors: Zhang Junhua , Ding Xiaobin , Peng Yuxing , Wang Mang 
Published: September 2002

AbstractFunctional Fe(III)‐phthalocyanine with vinyl groups was synthesized, and the structure was confirmed using Fourier transform infrared spectroscopy and elemental analysis, separately. A novel magnetic polymer microsphere with photoconductivity was prepared by copolymerization of styrene and functional Fe(III)‐phthalocyanine, which was used as a comonomer, in the presence of Fe3O4 magnetic fluid. The structure and morphology of magnetic polymer microspheres were determined by infrared analysis, elemental analysis, thermogravimetric analysis, and scanning electron microscopy. The magnetic responsiveness and photoconductivity were studied. The average size of the microspheres was 38.1 μ, with multidistribution. The microsphere has a good magnetic responsiveness and a good photoconductivity at 762.5 nm. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2609–2614, 2002
Rheological behavior of styrene‐maleic anhydride/polyol blends obtained through reactive processing
Authors: Bayram G. , Yilmazer U. , Xanthos M. , Patel S. H. 
Published: September 2002

AbstractThe condensation reaction of styrene‐maleic anhydride copolymer (SMAH) with polytetramethylene ether glycol (PTMEG) in the presence or absence of a hydrated zinc acetate catalyst was studied in a batch mixer. As a control, pure SMAH and an SMAH/catalyst blend were also subjected to the same processing conditions. The reaction characteristics of the blends were investigated by Fourier transform infrared spectroscopy (FTIR) and thermal and rheological analysis. FTIR analysis of the SMAH/PTMEG blend indicated ester formation. The addition of zinc acetate and/or PTMEG to SMAH decreased the glass transition temperature of pure SMAH. Oscillatory shear properties of storage modulus, G′, loss modulus, G″, and complex viscosity, η*, were measured. The SMAH/PTMEG/zinc acetate blend had higher G′, G″, and η* than the blend without the zinc acetate catalyst. The parameters of the relaxation spectra were calculated by using the experimental oscillatory data and the generalized Maxwell model. Zero shear viscosity and the mean relaxation time increased with addition of zinc acetate and/or PTMEG to SMAH as a result of chain extension/branching reactions. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2615–2623, 2002
Grafting and quaternization of 2‐(dimethylamino)ethyl methacrylate onto polyamide‐6 fabric pretreated with acetone
Authors: Ramadan A. M. , Mosleh S. , Gawish S. M. 
Published: September 2002

AbstractGrafting of polyamide (PA‐6) pretreated with acetone was done using 2‐(dimethylamino)ethyl methacrylate (DMAEM). It was found that the percentage graft yield of acetone‐pretreated PA fabric was higher than the untreated and there was a difference of 4% under the same conditions. The graft yield was studied as a function of the different variable conditions such as monomer concentration, reaction time, and temperature. The pretreated and grafted DMAEM‐PA fabric was then quaternized with different alkylating agents including ethyl iodide, benzyl chloride, and epichlorohydrin. The grafted and quaternized fabrics had a significant increase in dyeability. The quaternized fabric showed higher moisture regain compared to the ungrafted one and that could enhance the antistatic effect of such fibers. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2318–2323, 2001
A novel and efficient xanthenic dye–organometallic ion‐pair complex for photoinitiating polymerization
Authors: Grotzinger C. , Burget D. , Jacques P. , Fouassier J. P. 
Published: September 2002

AbstractThe photochemistry of the complex formed between a Rose Bengal dianion (RB) and a ferrocenium salt [Fc(+)] is described in this article. Stoichiometric analysis of the crystal showed that the Fc(+):RB ratio is 2:1. The dissociation percentage of complex RB(Fc)2 in several solvents was evaluated using fluorescence studies. In nonpolar media, in which most of the RB(Fc)2 exists as contact ion pairs, the photodegradation rate of the complex was found to be unaffected by the presence of oxygen and led to photoproducts capable of initiating a radical polymerization reaction. Because of this, the initiation step showed low oxygen inhibition. In fact, in a visible‐light photoinitiating system such as one composed of xanthene dye (Rose Bengal), ferrocenium salt, amine, and hydroperoxide, substituting the complex RB(Fc)2 for the sensitizing dye RB led to an increase in efficiency of the polymerization (especially under aerated conditions) as compared to that obtained in the presence of benzoyl phosphine oxide derivatives. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2368–2376, 2001
Electrooptical‐responsive microsphere with ferroelectric liquid crystalline segments
Authors: Yoshida Masahiro , Fan Xinghe , Uemura Yoshimitsu , Hatate Yasuo 
Published: September 2002

AbstractWe synthesized a ferroelectric liquid crystalline monomer (4‐[4′‐(7‐octeneloxy)benzoyloxy]benzoate‐2‐methylbutyester, OBBM) possessing both carboxyl p‐benzolxybenzoate and carboxyl (s)‐(‐)‐2‐methylbutylester as a mesogenic group in its side chain. The liquid crystalline and styrene monomers were employed to make matrices of microspheres prepared by dispersion, suspension, or emulsion polymerization. In this study, we investigated, in detail, physicochemical properties, thermal responses, and electrooptical responses of the microspheres possessing liquid crystalline abilities. The ferroelectric liquid crystalline monomer OBBM had a thermotropic liquid crystalline ability, two‐phase transition temperatures, and a Smectic C* texture, which is characteristic of ferroelectric liquid crystalline substances. The microspheres prepared also exhibited a liquid crystalline ability, and the phase‐transition temperatures toward the liquid crystalline segments into the microspheres prepared by copolymerizing the liquid crystalline and styrene monomers could be decreased with increasing of the styrene monomer. Furthermore, we found that the microspheres remarkably exhibited electrooptical responses at about 8 V. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2490–2499, 2001
Blends of polyamide 6, polycarbonate, and poly(propylene oxide). II. Reactive compatibilization–thermal degradation relationships
Authors: Costa Dilma A. , Oliveira Clara Marize F. 
Published: September 2002

AbstractThe thermal degradation of some blends of polyamide 6/polycarbonate (PA6/PC) and polyamide 6/polycarbonate/poly(propylene oxide) (PA6/PC/PPO) were investigated. The copolymer formed during the mixing of polyamide 6 and polycarbonate, at 240°C, for 30 min, increases the thermal stability of PA6/PC and of PA6/PC/PPO blends. This increase in the thermal stability occurs due to the plasticizing effect of PPO, which increases the mobility of the molecules of PA6 and PC, and consequently increases the probability of the reaction between the —NH2 and —O—CO—O groups of polyamide 6 and polycarbonate, respectively. The ternary blends with PPO (5–10% w/w) have lower thermal stability than PA6/PC blends. This is due to the decrease of miscibility between these polymers and the rise of the diluting effect. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2556–2562, 2001
Crystallization of vulcanizates. I. Low‐temperature crystallization as a function of extent of cure for polyisoprene vulcanized with tetramethylthiuram disulfide/sulfur and 2‐bisbenzothiazole‐2,2′‐disulfide/sulfur
Authors: Van Der Merwe M. J. , Gradwell M. H. S. , McGill W. J. 
Published: September 2002

AbstractThe crystallization of polyisoprene, vulcanized to various degrees of cure with tetramethylthiuram disulfide/sulfur and 2‐bisbenzothiazole‐2,2′‐disulfide (MBTS)/sulfur formulations, was studied in a density column at −25°C. The densities of vulcanizates before crystallization decrease progressively with cure time, which is ascribed to an increase in free volume occasioned by the formation of accelerator‐terminated pendent groups on the polymer chain. The induction period before the onset of crystallization increases and both the rate of and the degree of crystallization decrease with extent of cure. This is attributed primarily to the presence of residual pendent groups on the polymer chain and secondly to crosslink formation. The changes are more marked with MBTS formulations where pendent groups are more bulky. MBTS compounds fail to crystallize once vulcanized to the point where a gel has formed. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2565–2572, 2001