bluuebunny/crossref_metadata_2025 huggingface dataset:
Polymorphy in the stereostructure of periodic polymer backbones
Authors: Nakanishi Tsutomu , Okamoto Hajime , Kasahara Maki , Takeda Kyozaburo
Published: October 2003

We theoretically investigated the polymorphy of the stereostructures of a periodic polymer. Using the polymer's internal conformation parameters of bond lengths, bond angles, and internal rotation angles, we extended the mathematical treatment for designing polymer backbones. We considered those periodic polymers whose unit cell consists of one (m = 1), two (m = 2), or three (m = 3) kinds of atoms. Moreover, for these three types of polymers, we supposed two catenation types for the skeleton atoms; one is a “homorotatory” sequence and the other is a “heterorotatory” one. To specify the backbone's stereostructure, we introduced several conformation parameters such as the helical pitch number n, the translation distance d, and the inclination angle of the skeleton plane Θ. By combining these parameters, we can systematically understand the variety and the possible polymorphy in the stereostructure of a periodic polymer backbone. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2829–2849, 2003
Molecular dynamics of hydrophilic poly(propylene imine) dendrimers in aqueous solutions by 1H NMR relaxation
Authors: Malveau C. , Baille W. E. , Zhu X. X. , Ford W. T.
Published: October 2003

The local dynamics of three poly(propylene imine) dendrimers with hydrophilic triethylenoxy methyl ether terminal groups were studied in D2O by the measurement of the 1H NMR relaxation times, which were treated with the Lipari–Szabo model‐free approach. The results showed that the overall mobility increased with temperature and decreased with increasing dendrimer size. An Arrhenius trend was observed for both overall and local motions. The activation energy of overall tumbling increased from 11.3 to 17.5 kJ/mol with the dendrimer size. The local mobility decreased from the outer part to the inner part of the dendrimer and with the dendrimer size. The spatial restriction of local motions decreased with increasing temperature up to 55 °C and remained constant above 55 °C. Local motions were more restricted when the dendrimer size increased. The results showed that the hydrophilic end groups of the dendrimers were located preferentially at the periphery of the molecules and were extended in the aqueous environment. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2969–2975, 2003
Influence of moisture on the viscoelastic relaxations in long aliphatic chain contained semiaromatic polyamide, (PA9‐T) fiber
Authors: Uddin Ahmed Jalal , Ohkoshi Yutaka , Gotoh Yasuo , Nagura Masanobu , Hara Tetsuya
Published: October 2003

The effect of moisture on the mechanical relaxation processes of semiaromatic semicrystalline polyamides synthesized by a long‐chain aliphatic diamine and terephthalic acid was investigated by dynamic viscoelastic analysis (DVA) and differential scanning calorimetry (DSC). Moreover, the implication of moisture with the amorphous and crystalline domains was also examined by temperature‐dependent wide‐angle X‐ray diffraction and Fourier transform infrared spectra. The characteristics of the relaxations such as α, β, γ, and the pronounced peak shoulder appeared at 25–100 °C in DVA tan δ curves were found to be strongly susceptible to the presence of moisture. With moisture evaporation, the peak shoulder of 25–100 °C and the β‐relaxation disappeared. The former is anticipated to originate from to the side group motion of hydrogen‐bonded water, whereas the later one is from the motions of the amide–water complex units. With the disappearance of the β‐relaxation, the γ‐relaxation appeared simultaneously in much lower temperatures and ultimately coupled with the δ‐relaxation. The γ‐relaxation is attributed to be associated with the molecular motion of the amide group and δ‐relaxation with for the motion of the methylene units. The existence of two types of water was identified in the polymer, namely, tightly bound and loosely bound. The tightly bound water is believed to be directly connected by hydrogen bonding with the strong polar groups and the loosely bound water weakly links with those connected water making hydrogen bridges. The moisture acts as a plasticizer in the polymer matrix, which causes quite a large depression in its glass transition temperature (Tg). WAXD and FTIR studies corroborated the existence of water solely in amorphous regions, i.e., no rapport of water with the crystalline parts. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2878–2891, 2003
End‐group effect on physical aging and polymer properties for poly(ether sulfones)
Authors: Muggli M. W. , Ward T. C. , Tchatchoua C. , Ji Q. , Mcgrath J. E.
Published: October 2003

The physical aging properties of amorphous thermoplastics having various terminal groups were investigated with creep recovery and linear dilatometry. The structure of the chain end groups affected physical aging at lower molecular weights; however, above the critical molecular weight for entanglements the end‐group effect on aging diminished. Experimental densities and glass‐transition temperatures were also end‐group dependent. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2850–2860, 2003
Orientation and structure development in polyamide 6 fibers upon drawing
Authors: Vasanthan Nadarajah
Published: October 2003

Drawn polyamide 6 (PA6) fibers were characterized with X‐ray diffraction, Fourier transform infrared (FTIR) spectroscopy, density measurement, and optical microscopy. The α and amorphous orientation functions were determined by polarized FTIR spectroscopy. It was demonstrated for the first time that the infrared band at 1124 cm−1 could be used to determine the amorphous orientation functions of drawn PA6 fibers and films. α, γ, and amorphous orientation functions increased rapidly at lower draw ratios and increased slowly at higher draw ratios. The amorphous orientation functions measured by polarized FTIR spectroscopy did not agree with those determined by a combination of wide‐angle X‐ray diffraction (WAXD) and optical birefringence measurements, attributed to possible error in the estimated birefringence. The α and γ crystallinity of undrawn fiber (DR = 1) were ∼24 and 6%, respectively, which increased to ∼13 and 39% at a draw ratio of 4 (DR = 4). The WAXD data suggested that γ crystal grew in the hydrogen‐bonding direction as well as the van der Waals direction during deformation. The decrease in γ crystallinity and increase in γ crystallite size with the draw ratio were attributed to the disappearance of small crystallites and an increase in the average γ crystallite size population during the deformation process. The increase in density with the draw ratio was attributed to crystal‐to‐crystal transformation as well as strain‐induced crystallization. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2870–2877, 2003
Effects of ultrasonic treatment on unfilled butadiene rubber
Authors: Oh Jeong Seok , Ghose Sayata , Isayev A. I.
Published: October 2003

The ultrasonic treatment of unfilled butadiene rubber (BR) gum with a grooved‐barrel ultrasonic reactor was carried out, leading to changes in the structure and physical properties. The ultrasonic treatment of BR gum led to gel formation, with the amount dependent on the amplitude. The rheological and mechanical properties of the ultrasonically treated samples and their vulcanizates were measured and compared with those of the virgin samples. Gel permeation chromatography measurements of the sol part of the virgin and the treated samples were carried out. Rheological property and molecular weight measurements indicated the creation of a branched structure and the occurrence of degradation in ultrasonically treated BR gum. Because of degradation, the tensile strength and Young's modulus of treated BR were lower than those of untreated BR, whereas the elongation at break was practically intact. Differential scanning calorimetry (DSC) curves at a high‐temperature range showed exothermic peaks with enthalpy reduction in the treated BR, indicating a decrease in the number of double bonds due to gel formation. DSC curves at a low‐temperature range indicated increased crystallinity in the treated samples. Competing reactions of gel formation, branching, and degradation occurred during the ultrasonic treatment. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2959–2968, 2003
Intramolecular screening effects in nondilute polymer solutions: An equation‐of‐state approach
Authors: Berg Lennart P. , Painter Paul C.
Published: October 2003

In a previous article, we presented a simple modification of the traditional Flory–Huggins theory that took intramolecular screening effects (or same chain contacts) into account. In this article, we present a natural extension of that work, in which free‐volume effects are also explained with an equation‐of‐state model. The predictions of the interaction parameter, χ, for several polymer–solvent systems are presented, over the entire concentration range, in θ solvents and good solvents. A geometric mean assumption is applied to the calculation of an exchange energy interaction term. The predictions of χ are successful to various degrees when internal pressures are used, whereas the use of solubility parameters in most cases produces fairly good agreement with experimental results. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2911–2922, 2003
Multiple melting and crystallization of nylon‐66/montmorillonite nanocomposites
Authors: Zhang Qing‐Xin , Yu Zhong‐Zhen , Yang Mingshu , Ma Jun , Mai Yiu‐Wing
Published: October 2003

Nylon‐66 nanocomposites were prepared by melt‐compounding nylon‐66 with organically modified montmorillonite (MMT). The organic MMT layers were exfoliated in a nylon‐66 matrix as confirmed by wide‐angle X‐ray diffraction (WAXD) and transmission electron microscopy. The presence of MMT layers increased the crystallization temperature of nylon‐66 because of the heterogeneous nucleation of MMT. Multiple melting behavior was observed in the nylon‐66/MMT nanocomposites, and the MMT layers induced the formation of form II spherulites of nylon‐66. The crystallite sizes L100 and L010 of nylon‐66, determined by WAXD, decreased with an increasing MMT content. High‐temperature WAXD was performed to determine the Brill transition in the nylon‐66/MMT nanocomposites. Polarized optical microscopy demonstrated that the dimension of nylon‐66 spherulites decreased because of the effect of the MMT layers. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2861–2869, 2003
Thermal behavior of drawn acrylic fibers
Authors: Sen K. , Bajaj P. , Sreekumar T.V.
Published: October 2003

The effect of stretching on the thermal behavior of acrylic fibers was investigated with differential scanning calorimetry (DSC), thermogravimetric analysis, and Fourier transform infrared spectroscopy (FTIR). In air atmosphere, the peak temperature of the dynamic DSC thermogram was significantly lowered from 289 to 273 °C when the gel fibers (undrawn) were drawn to a draw ratio of 11.2. However, the initiation temperature was unchanged at 202 °C. The shoulder in the region of 310–380 °C was gradually converted to a sharp peak during the drawing process. However, the dynamic DSC in nitrogen atmosphere did not change in all cases. In air atmosphere the total heat liberated, ΔH, for gel fiber was 851 J g−1. However, upon drawing to 11.2, ΔH increased to 1580 J g−1 showing an increase in the total chemical changes. An intimate relationship of chemical changes during the heating process was observed with FTIR of heated samples at various temperatures. The initiation of a DSC exotherm in air begins with nitrile cyclization, and subsequently dehydrogenation was initiated between 220 and 260 °C. An increase in the X‐ray orientation factor and sonic modulus gave a correlation between the stretching draw ratio and crystalline/overall molecular orientation. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2949–2958, 2003
Structural investigation of water‐induced phase transitions of poly(ethylene imine). III. The thermal behavior of hydrates and the construction of a phase diagram
Authors: Hashida Tomoko , Tashiro Kohji , Inaki Yoshiaki
Published: October 2003

The thermal behavior of poly(ethylene imine) (PEI) hydrates in a water vapor atmosphere was investigated through temperature‐dependent measurements of infrared spectra and X‐ray diffraction. Almost perfectly dried anhydrate melted at about 60 °C during the heating process. Anhydrate containing a small amount of water showed a phase transition to a mixture of hemihydrate and sesquihydrate around 40 °C, at which point the ethylene imine (EI)/water ratio was 1/0.5 in the hemihydrate and 1/1.5 in the sesquihydrate. The hemihydrate transferred to the sesquihydrate around 60 °C, and the latter melted above 80 °C. When the starting PEI sample contained a greater amount of water and consisted of hemihydrate and sesquihydrate, the hemihydrate transferred to the sesquihydrate via heating, and the latter melted around 75 °C. For a sample of dihydrate (EI/water ratio = 1/2) containing an appreciably large amount of water, it transferred to the sesquihydrate around 65 °C, and the latter melted above 90 °C. A sample of dihydrate with a much higher water content existed up to 110 °C and then melted; during this period, no transition to the sesquihydrate was observed. In this way, the starting crystalline phases were found to change for anhydrate and various types of hydrates. Their transition behaviors varied according to the water content. From these data, a phase diagram was successfully derived as a function of the temperature and water content. This phase diagram allowed us to predict the transition behavior during the hydration process at various constant temperatures. For example, at 60 °C, a molten sample should crystallize into a mixture of hemihydrate and sesquihydrate at first, and the hemihydrate should transfer to the sesquihydrate with increasing water content. The latter should change to the dihydrate in the final stage. This prediction was checked with time‐resolved measurements of X‐ray diffraction and infrared spectra during the hydration process at the corresponding temperature; this led to the establishment of the phase diagram. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2937–2948, 2003
Crystallization behavior and thermal stability of poly(trimethylene terephthalate)/clay nanocomposites
Authors: Ou Cheng‐Fang
Published: October 2003

Poly(trimethylene terephthalate) (PTT)/montmorillonite (MMT) nanocomposites were prepared by the solution intercalation method. Two different kinds of clay were organomodified with an intercalation agent of cetyltrimetylammonium chloride (CMC). X‐ray diffraction (XRD) indicated that the layers of MMT were intercalated by CMC, and interlayer spacing was a function of the cationic exchange capacity of clay. The XRD studies demonstrated that the interlayer spacing of organoclay in the nanocomposites depends on the amount of organoclay. From the results of differential scanning calorimetric analysis, it was found that clay behaves as a nucleating agent and enhances the crystallization rate of PTT. The maximum enhancement of the crystallization rate for the nanocomposites was observed in nanocomposites containing about 1 wt % organoclay with a range of 1–15 wt %. From thermogravimetric analysis, we found that the thermal stability of the nanocomposites was enhanced by the addition of 1–10 wt % organoclay. According to transmission electron microscopy, the organoclay particle was highly dispersed in the PTT matrix without a large agglomeration of particles for a low organoclay content (5 wt %). However, an agglomerated structure did form in the PTT matrix at a 15 wt % organoclay content. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2902–2910, 2003
Characterization of heavy ion tracks in polymers by transmission electron microscopy
Authors: Adla A. , Fuess H. , Trautmann C.
Published: October 2003

Ultrathin sections of two polymers—poly(ethylene terephthalate) and polyimide—were irradiated with heavy ions of 11.1 MeV per nucleon. The size and morphology of the latent tracks were examined with transmission electron microscopy. Polymers readily decomposed under the imaging electron beam. Samples were therefore stained with either osmium tetroxide or ruthenium tetroxide before and/or after ion irradiation. This treatment significantly reduced the radiolytic sensitivity. In addition, however, with dynamic video electron imaging, quasi‐instantaneous damage processes were observed within seconds of observation, modifying in particular both tracks in the bulk and to a lesser extent those on the two confining surfaces. The staining agent was embedded into amorphous regions of the matrix as metallic nanoparticles. Prestained tracks appeared as bright cylindrical regions with diameters of ∼6–10 nm. In ultrathin samples, the central track region showed a significant loss of material and even an open hole. Following poststaining, tracks exhibited a dark contrast because of preferential diffusion of the staining agent into the tracks. Poststained tracks were larger than prestained tracks. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2892–2901, 2003
Solubility of N2 in poly(α‐n‐hexyl‐β,L‐aspartate): Temperature and force‐field dependence
Authors: Zazueta D. Alfonso , Curcó David , Alemán Carlos , Muñoz‐Guerra Sebastián
Published: October 2003

The solubility of N2 in poly(α‐n‐hexyl‐β,L‐aspartate), a stereoregular poly(β‐peptide), was investigated with atomistic Monte Carlo simulations. The structure of this material is intermediate between that of polymers able to form a three‐dimensional crystal lattice and that of liquid‐crystalline polymers with a biphasic distribution. The dependence of the calculated solubility coefficients on both the parameters of the force field and the temperature was examined. The results are compared with recently reported experimental data. Furthermore, the motion of the penetrant molecules within the polymer matrix was analyzed. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2928–2936, 2003
Time‐resolved Fourier transform infrared/attenuated total reflection spectroscopy for the measurement of molecular diffusion in polymers
Authors: Elabd Yossef A. , Baschetti Marco Giacinti , Barbari Timothy A.
Published: October 2003

Over the past 2 decades, the use of time‐resolved Fourier transform infrared/attenuated total reflection (ATR) spectroscopy for the measurement of diffusion in polymers has grown. ATR is a powerful technique for the measurement of diffusion in polymers because it is an in situ technique that is relatively inexpensive, provides reliable short‐time data, and provides a wealth of information at the molecular level. This article highlights the technique and its application to numerous studies, ranging from the diffusion of drugs in human skin to chemical warfare agents in barrier materials. In addition to these topics, recent studies with ATR to quantify and model molecular interactions during the diffusion process are reviewed. In the future, the ATR technique may have an impact on a variety of emerging fields in which diffusion in polymers plays an important role, such as fuel cells, membrane separation, sensors, and drug delivery. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2794–2807, 2003
Macromolecules at surfaces: Research challenges and opportunities from tribology to biology
Authors: Granick Steve , Kumar Sanat K. , Amis Eric J. , Antonietti Markus , Balazs Anna C. , Chakraborty Arup K. , Grest Gary S. , Hawker Craig , Janmey Paul , Kramer Edward J. , Nuzzo Ralph , Russell Thomas P. , Safinya Cyrus R.
Published: October 2003

A comprehensive review of ongoing and recommended research directions concerning the structure, dynamics, and interfacial activity of synthetic and naturally occurring macromolecules at the solid–liquid interface is presented. Many new developments stem from the ability to target new size regimes of 1–100 nm. These rapid developments are reviewed critically with respect to chemical synthesis, processing, structural characterization, dynamic processes, and theoretical and computational analysis. The common problems shared by flat and particulate surfaces are emphasized. A broad spectrum of material properties are discussed, from the control of interfacial friction between surfaces in moving contact, to the mechanical strength and durability of the interfaces in hybrid materials, to optical and electronic properties. Future research opportunities are identified that involve (1) the emergence of nanoscale material properties, (2) polymer‐assisted nanostructures, and (3) the crossroads between interfacial science and biological and bioinspired applications. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2755–2793, 2003
Acaricidal effects of cardiac glycosides, azadirachtin and neem oil against the camel tick, Hyalomma dromedarii (Acari: Ixodidae)
Authors: Al‐Rajhy DiefAlla H , Alahmed Azzam M , Hussein Hamdy I , Kheir Salah M
Published: October 2003

The cardiac glycoside, digitoxin, from Digitalis purpurea L (Scrophulariaceae), a cardiac glycosidal (cardenolide) extract from Calotropis procera (Ait) R Br (Asclepiadaceae), azadirachtin and neem oil from Azadirachta indica A Juss (Meliaceae) were tested for their effects against larvae and adult stages of the camel tick, Hyalomma dromedarii Koch (Acari: Ixodidae). The contact LC50 values of the first three materials against adults were 4.08, 9.63 and >40.7 µg cm−2, respectively, whereas the dipping LC50 values of the four materials were 409.9, 1096, >5000 and >5000 mg litre−1, respectively. Contact and dipping LC50 values of the extract and azadirachtin against larvae were 6.16, >20.3 µg cm−2 and 587.7 and >2500 mg litre−1, respectively. Azadirachtin had no effects on egg production or feeding of adults up to 5000 mg litre−1; however at 2500 mg litre−1, it caused significant reduction in feeding activity of larve, prolonged the period for moulting to nymphal stage, and caused 60% reduction in moultability. Results of the two cardiac glycoside materials are comparable with those of several commercial acaricides. The risks and benefits associated with the use of cardiac glycosides are considered. Copyright © 2003 Society of Chemical Industry
Association of MACE‐based insecticide resistance in Myzus persicae with reproductive rate, response to alarm pheromone and vulnerability to attack by Aphidius colemani
Authors: Foster Stephen P , Kift Neil B , Baverstock Jason , Sime Sue , Reynolds Kelly , Jones Julie E , Thompson Robin , Tatchell G Mark
Published: October 2003

Reproductive success and response to alarm pheromone, both potentially important components of fitness, were assessed using clones of Myzus persicae (Sulzer) to establish associations with insecticide resistance conferred by insensitive modified acetylcholinesterase (MACE). Both traits showed significant trends that were apparently related to this mechanism. MACE forms appeared to reproduce at slower rates than non‐MACE forms expressing moderate (R1) levels of another resistance mechanism based on elevated carboxylesterase. However, MACE forms were more responsive to alarm pheromone than their non‐MACE counterparts. The potential implications for parasitoid performance were tested using two clones showing clear differences in alarm response. The level of parasitism of M persicae by the parasitoid Aphidius colemani (Viereck) was significantly lower in MACE forms on pepper crops compared to non‐MACE forms. In addition, the distribution of MACE and non‐MACE forms differed on the pepper plants, with more MACE forms being found on the growing points. The presence of the parasitoid A colemani did not alter this change in distribution. Copyright © 2003 Society of Chemical Industry
Chlorpyrifos residue levels in avian food items following applications of a commercial EC formulation to alfalfa and citrus
Authors: Brewer Larry W , McQuillen Harry L , Mayes Monte A , Stafford Jennifer M , Tank Susan L
Published: October 2003

Two 10‐day field residue studies were conducted to measure the amount of chlorpyrifos residue found in typical avian food following applications of a commercial 480 g liter−1 EC (Lorsban® 4E) at 1.1 kg AI ha−1 (1 lb AI acre−1) to alfalfa and at 2.3 kg AI ha−1 (2.0 lb AI acre−1) to citrus. Avian food items used in these studies included: crickets (Acheta domestica (L)), earthworms (Lumbricus terrestris L), darkling ground beetle larvae (Tenebrio molitor L), seed heads (Triticum sp), and naturally occurring flying and ground‐dwelling insects. The studies incorporated a design involving three main study plots placed within larger treated areas of an alfalfa crop and a mature orange grove. The three main study plots represented three replications and each contained four sub‐plots. One sub‐plot, on each study plot, was sampled on day 0 (2‐h post‐application), day 1, day 5 and day 10 post‐application. Chlorpyrifos residues were present in all avian food sampled following the application; however, residue levels were lower than estimated residue values typically used by the US EPA to establish expected environmental concentration (EEC) used in screening assessments of risk to terrestrial wildlife. Copyright © 2003 Society of Chemical Industry
Inheritance of resistance to Bt canola in a field‐derived population of Plutella xylostella
Authors: Sayyed Ali H , Schuler Tanja H , Wright Denis J
Published: October 2003

Crops expressing Bacillus thuringiensis (Bt) insecticidal Cry proteins are grown on millions of hectares. Recommendations to delay resistance are based on a high expression/refugia strategy that aims to kill resistant heterozygotes and enable some susceptible insects to survive. Leaf‐dip bioassays on F1 crosses of Malaysian populations of diamondback moth (Plutella xylostella (L)) showed that Cry1Ac resistance was not fully recessive. The survival of ca 50% of heterozygotes on Bt canola (Brassica napus L) leaves expressing low concentrations of Cry1Ac agreed with a non‐fully‐recessive model for resistance. Extrapolations based on log dose‐logit mortality regressions for heterozygotes using leaf‐dip bioassays showed that a relatively high level of expression, of ca 2000 ng Cry1Ac mg−1 total leaf protein, would be required to give 90% mortality to heterozygotes. If high enough levels of expression of Bt toxin to kill heterozygotes cannot be achieved and maintained under field conditions, the effectiveness of the high‐dose/refugia strategy would be reduced. Copyright © 2003 Society of Chemical Industry
The effects of repeated applications of the molluscicide metaldehyde and the biocontrol nematodePhasmarhabditis hermaphroditaon molluscs, earthworms, nematodes, acarids and collembolans: a two‐year study in north‐west Spain
Authors: Iglesias Javier , Castillejo José , Castro Ramón
Published: October 2003

Over two years, six consecutive field experiments were done in which the chemical molluscicide metaldehyde and the nematode biocontrol agentPhasmarhabditis hermaphrodita(Schneider) were applied at the standard field rates to replicated mini‐plots successively planted with lettuce, Brussels sprouts, leaf beet and cabbage, to compare the effectiveness of different treatments in reducing slug damage to the crops. Soil samples from each plot were taken prior to the start of the experiments, and then monthly, to assess the populations of slugs, snails, earthworms, nematodes, acarids and collembolans. The experiments were done on the same site and each plot received the same treatment in the six experiments. The six treatments were: (1) untreated controls, (2) metaldehyde pellets, (3 and 4) nematodes applied to the planted area 3 days prior to planting without or with previous application of cow manure slurry, (5) nematodes applied to the area surrounding the planted area 3 days prior to planting, and (6) nematodes applied to the planted area once (only in the first of the six consecutive experiments). Only the metaldehyde treatment and the nematodes applied to the planted area at the beginning of each experiment without previous application of manure significantly reduced slug damage to the plants, and only metaldehyde reduced the number of slugs contaminating the harvested plants. The numbers of slugs, snails and earthworms in soil samples were compared among the six treatments tested: with respect to the untreated controls, the numbers ofDeroceras reticulatum(Müller) were significantly affected only in the metaldehyde plots, and the numbers ofArion aterL only in the plots treated with nematodes applied to the planted area 3 days prior to planting without previous application of manure; numbers of snails (Ponentina ponentina(Morelet) andOxychilus helveticus(Blum)) were not affected by the treatment. The total numbers of all earthworm species and ofLumbricusspp were unaffected by the treatment, butDendrobaenaspp increased significantly in the plots treated with manure. The numbers of nematodes, acarids and collembolans in soil samples were compared between the untreated controls and the treatments with nematodes applied 3 days prior to planting to the planted area or to the surrounding area, without previous application of manure: the treatment had a significant effect on the number of nematodes in soil samples, but acarids and collembolans were unaffected. Copyright © 2003 Society of Chemical Industry
Genetic basis of resistance and studies on cross‐resistance in a population of diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae)
Authors: Liang Pei , Gao Xi‐Wu , Zheng Bing‐Zong
Published: October 2003

The genetic basis of abamectin resistance was studied in a strain of the diamondback moth, Plutella xylostella (L), following laboratory selection of a field population collected at Xuanhua, Hebei Province, China. Data from the testing of F1 progeny from reciprocal crosses between abamectin‐resistant and abamectin‐susceptible strains indicated that resistance might be autosomal and incompletely recessive with a degree of dominance of −0.13. Chi‐squared analyses from the response of a backcross of crossed F1 progeny and the resistant strain and F2 progeny were highly significant, suggesting that the resistance was probably controlled by more than one gene. The results of cross‐resistance studies showed that there was little cross‐resistance between abamectin and four pyrethroid insecticides (deltamethrin, beta‐cypermethrin, fenvalerate and bifenthrin) and no cross‐resistance between abamectin and the acylureas chlorfluazuron or flufenoxuron. Copyright © 2003 Society of Chemical Industry
Antitumor activity of total alkaloid fraction of solanum pseudocapsicum leaves
Authors: Badami Shrishailappa , Manohara Reddy S. A. , Kumar E. P. , Vijayan P. , Suresh B.
Published: October 2003

The total alkaloid fraction of the methanolic extract of Solanum pseudocapsicum leaves was tested for its in‐vivo antitumor activity against Dalton's Lymphoma Ascites model in mice. The total alkaloid fraction at 2.5 and 5.0 mg/kg body weight doses exhibited antitumor activity as revealed by the signiﬁcant increase in the mean survival time and the percentage increase in life span of tumor bearing mice. The antitumor activity observed may be due to its cytotoxic properties. However the treatment caused a signiﬁcant decrease in the body weight below the normal indicating the toxicity of the treatment. Copyright © 2003 John Wiley & Sons, Ltd.
Antiﬁlarial potential of the fruits and leaves extracts of Pongamia pinnata on cattle filarial parasite Setaria cervi
Authors: Uddin Qamar , Parveen Nazneen , Khan Nizam U. , Singhal K. C.
Published: October 2003

The effect of aqueous and alcohol extracts of the fruits and leaves of Pongamia pinnata (Linn.) Merr. (Syn. Pongamia glabra Vent, leguminosae) on the spontaneous movements of both the whole worm and the nerve–muscle preparation of Setaria cervi and on the survival of microﬁlariae in vitro was studied. The aqueous and alcohol extracts of fruits and the alcohol extract of leaves caused an inhibition of spontaneous movements of the whole worm and the nerve–muscle preparation of S. cervi. The initial stimulatory effect was not observed with the aqueous extract of fruits on the nerve–muscle preparation. The concentration required to inhibit the movements of the whole worm preparation was 250 µg/mL for aqueous, 120 µg/mL for alcohol extract of fruits and 270 µg/mL for alcohol extracts of the leaves. The concentrations of P. pinnata extracts required to produce an equivalent effect on the nerve–muscle preparation were 25 µg/mL, 5 µg/mL and 20 µg/mL, respectively, suggesting a cuticular permeability barrier. Copyright © 2003 John Wiley & Sons, Ltd.
Antimicrobial activity of essential oil and methanol extracts of Achillea sintenisii Hub. Mor. (Asteraceae)
Authors: Sökmen Atalay , Vardar‐Ünlü Gülhan , Polissiou Moschos , Daferera Dimitra , Sökmen Münevver , Dönmez Erol
Published: October 2003

The essential oil, obtained by Clevenger distillation, and water‐soluble and water‐insoluble parts of the methanol extracts of Achillea sintenisii Hub. Mor. were individually assayed for their antimicrobial activities against 12 bacteria and two yeasts, Candida albicans and C. krusei. No activity was exhibited by the water‐soluble subfraction, whereas both the water‐insoluble subfraction of the methanol extracts and the essential oil were found to be active against some test microorganisms studied. Since the essential oil possessed stronger activity than the other extracts tested, it was further fractionated and the fractions were evaluated for their antimicrobial activity, followed by GC‐MS analysis, resulting in the identiﬁcation of 32 compounds which constituted 90.2% of the total oil. The GC‐MS analysis of the oil and its fractions revealed that the main components of the oil, e.g. camphor and eucalyptol, possessed appreciable activity against C. albicans and Clostridium perfringens. The ﬁndings presented here also suggest that the other constituents of the oil, e.g. borneol and piperitone can also be taken into account for the activity observed. Copyright © 2003 John Wiley & Sons, Ltd.
Effect of 14‐deoxyandrographolide on calcium‐mediated rat uterine smooth muscle contractility
Authors: Burgos Rafael A. , Loyola Mario , Hidalgo María A. , Labranche Timothy P. , Hancke Juan L.
Published: October 2003

In this study, the effect of 14‐deoxyandrographolide (14‐DAP) on calcium channel‐dependent rat uterine smooth muscle contraction was evaluated. Using a tissue bath preparation, 14‐DAP was able to reduce the contractile response to 0.3 and 3.0 mm of CaCl2, with an IC50 of 1.24 ± 0.23 × 10−5 m and 5.94 ± 0.29 × 10−5 m, respectively. 14‐DAP shifted the CaCl2 cumulative dose response curve to the right, increasing the EC50 from 2.08 ± 0.20 × 10−4 m to 4.22 ± 0.22 × 10−4 m (5 µm 14‐DAP) and 2.5 ± 1.0 × 10−3 m (50 µm 14‐DAP). In order to determine if 14‐DAP had any effect on intracellular calcium, the relaxant response to 14‐DAP following contraction by oxytocin, PGF2α and vanadate in Ca+2‐free solution was compared with that of isoproterenol and phenylbutazone. While isoproterenol and phenylbutazone relaxed the smooth muscle in a dose‐dependent manner, 14‐DAP did not have any effect on either the oxytocin, PGF2α or vanadate‐induced smooth muscle contraction. Based on these data, it appears that 14‐DAP is an uterine smooth muscle relaxant which produces a selective blockade of voltage operated calcium channels. Copyright © 2003 John Wiley & Sons, Ltd.
Protective effect of Astragali radix extract on interleukin 1β‐induced inﬂammation in human amnion
Authors: Shon Yun‐Hee , Nam Kyung‐Soo
Published: October 2003

The aim of this study was to investigate the effect of Astragali radix extract on interleukin (IL)‐6 and tumour necrosis factor (TNF)‐α production and prostaglandin E2 (PGE2) and leukotriene C4 (LTC4) release from IL‐1β‐stimulated human amnion. Primary monolayer cultures of amnion cells were established from women undergoing elective caesarean section before the onset of labour. Production of both IL‐6 and TNF‐α was stimulated in a concentration‐dependent manner by proinﬂammatory cytokine IL‐1β (0.01–10 ng/mL). Astragalus extract inhibited IL‐6 production by approximately 75% from cells under IL‐1β‐stimulated conditions. Treatment of amnion cells with IL‐1β (0.01–10 ng/mL) resulted in a signiﬁcant increase in PGE2 release. Incubation of the cells with the extract for 24 h signiﬁcantly inhibited IL‐1β‐induced PGE2 production. A concentration‐dependent increase in LTC4 production by amnion cells occurred in response to IL‐1β. Astragalus extract blocked the effect of IL‐1β in LTC4 production in human amnion. These results indicate that Astragali radix has a broad antiinﬂammatory effect in human amnion and may be considered a promising agent to protect preterm labour. Copyright © 2003 John Wiley & Sons, Ltd.
Pharmacokinetic and pharmacological interactions between ticlopidine hydrochloride and Kangen‐Karyu – Chinese traditional herbal medicine
Authors: Makino Toshiaki , Wakushima Hannosuke , Okamoto Takuya , Okukubo Yasuhiro , Deguchi Yoshiharu , Kano Yoshihiro
Published: October 2003

Kangen‐Karyu (KGK), containing peony root, cnidium rhizome, safﬂower, cyperus rhizome, saussurea root and Salvia miltiorrhiza root, is a Chinese traditional medicine formula to invigorate the ‘blood’ and dispel ‘blood stasis’, arising from poor blood circulation. The present study evaluated the pharmacokinetic and pharmacological interactions between KGK and ticlopidine hydrochloride. Ticlopidine was administered orally or intravenously to KGK‐treated rats, and its plasma concentrations were measured. KGK did not signiﬁcantly affect the pharmacokinetic parameters of ticlopidine in rats treated with both oral and intravenous administration. Ticlopidine alone signiﬁcantly prolonged the mouse tail‐bleeding time and adenosine 5′‐diphosphate‐induced ex vivo platelet aggregation, which was slightly augmented by KGK. It is suggested that the combined therapy of ticlopidine and KGK may augment the antithrombotic effects, and that the dosage of ticlopidine should be reduced to prevent thrombotic thrombocytopenic purpura, a severe adverse effect of ticlopidine. Copyright © 2003 John Wiley & Sons, Ltd.
Antioxidant activity of extracts from Alpinia katsumadai seed
Authors: Lee Si Eun , Shin Hyun‐Tak , Hwang Hyun Jin , Kim Jeong Hee
Published: October 2003

Alpinia katsumadai (Zingiberaceae) has been widely used in traditional Chinese medicine to treat a variety of conditions such as emesis and gastric disorders. However, very little is known about the cellular actions by which this plant mediates its therapeutic effects. Various aspects of antioxidant activity were evaluated in a total extract derived from Alpinia katsumadai seed in this study. Relatively high levels of 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activity were detected in the total extract (IC50 1.6 µg/mL). Other known compounds such as (−)‐epigallocatechine‐3‐gallate (EGCG) and resveratrol showed IC50 values of <0.8 and 4.8 µg/mL, respectively. The total extract also enhanced the viability of Chinese hamster lung ﬁbroblast (V79‐4) cells and inhibited H2O2‐induced apoptosis. The total extract of Alpinia katsumadai also dose‐dependently enhanced the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in V79‐4 cells, and these effects were comparable to other antioxidant compounds such as EGCG and resveratrol. Taken together, our ﬁndings show that Alpinia katsumadai contains signiﬁcant antioxidant activity. Copyright © 2003 John Wiley & Sons, Ltd.
Virucidal activity of essential oils from aromatic plants of San Luis, Argentina
Authors: García C. C. , Talarico L. , Almeida N. , Colombres S. , Duschatzky C. , Damonte E. B.
Published: October 2003

Essential oils obtained from eight aromatic plants of San Luis Province, Argentina, were screened for virucidal activity against herpes simplex virus type 1 (HSV‐1), Junin virus (JUNV) and dengue virus type 2 (DEN‐2). The most potent inhibition was observed with the essential oil of Lippia junelliana and Lippia turbinata against JUNV with virucidal concentration 50% (VC50) values in the range 14–20 ppm, whereas Aloysia gratissima, Heterotheca latifolia and Tessaria absinthioides inhibited JUNV in the range 52–90 ppm. The virucidal activity was time‐ and temperature‐dependent. The essential oils of A. gratissima, Artemisia douglasiana, Eupatorium patens and T. absinthioides inactivated HSV‐1 at 65–125 ppm. However, only A. douglasiana and E. patens had any discernible effect on DEN‐2 infectivity with VC50 values of 60 and 150 ppm, respectively. Copyright © 2003 John Wiley & Sons, Ltd.
Analgesic properties of some ethiopian medicinal plants in different models of nociception in mice
Authors: Makonnen Eyasu , Debella Asfaw , Abebe Dawit , Teka Frehiwot
Published: October 2003

Many people use analgesic plants to relieve pain and inﬂammation though most of them have not yet been proved to possess such properties. The objective of the present study was to screen the aqueous and ethanol extracts of four Ethiopian traditionally used medicinal plants for analgesic properties. Aqueous and ethanol extracts of the plant materials were screened for their analgesic properties in mice using tail‐ﬂick, hot‐plate and tail‐pinch tests at three dose levels. Normal saline and standard analgesics were employed as negative and positive controls, respectively. The plants subject for the present screening were Ocimum suave, Ocimum lamiifolium, Lippia adoensis, and Ajuga remota. All extracts were observed to possess analgesic properties with varying potencies in tail‐ﬂick and hot‐plate tests. Analgesic activity, however was not observed with tail‐pinch test. The analgesic potencies also varied with concentrations and time after administration. From the present ﬁndings, it can be concluded that the extracts of all the plant materials have got analgesic properties with fast onset of action whose mechanisms need to be investigated further. Copyright © 2003 John Wiley & Sons, Ltd.
In vitro immunopotentiating properties and tumour cell toxicity induced by Lophophora williamsii (peyote) cactus methanolic extract
Authors: Franco‐Molina M. , Gomez‐Flores R. , Tamez‐Guerra P. , Tamez‐Guerra R. , Castillo‐Leon L. , Rodríguez‐Padilla C.
Published: October 2003

Lophophora williamsii, also known as peyote, is found primarily in dry regions from Central Mexico, including the Mexican States of Nayarit, San Luis Potosí, Zacatecas, Nuevo León, Chihuahua, Coahuila and Tamaulipas, to Texas particularly in regions along Rio Grande. Peyote extracts have been associated with stimulating the central nervous system and regulating blood pressure, sleep, hunger and thirst. However, there is no evidence of any effect of peyote on the immune system or against tumour cell growth. The present study was designed to evaluate the in vitro effects of peyote methanolic extracts on some parameters of mouse and human leukocyte immunocompetence and tumour cell growth. Peyote extract (0.18–18 µg/mL) activated nitric oxide production by murine macrophages, and stimulated up to 2.4‐fold proliferation of murine thymic lymphocytes. In addition, peyote extract induced up to 1.85‐, 2.29‐ and 1.89‐fold increases in mRNA signal of IL‐1, IL‐6 and IL‐8 by human leukocytes. Also examined were the effects of peyote extracts on murine lymphoma L5178Y‐R and ﬁbroblastoma L929, and human myeloid U937 and mammary gland MCF7 tumour cell growth using 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide (MTT). Peyote extracts were toxic for MCF7, L5178Y‐R, U937 and L929 (18 mg/mL peyote extract caused 1.3%, 8%, 45% and 60% viability respectively) cell lines. Copyright © 2003 John Wiley & Sons, Ltd.
Protection by hot water extract of Panax notoginseng on chronic ethanol‐induced hepatotoxicity
Authors: Lin Chih‐Fu , Wong Kar‐Lok , Wu Rick Sai‐Chuen , Huang Tian‐Chyuan , Liu Chi‐Feng
Published: October 2003

The purpose of this study was to investigate the antioxidant effects of a hot water extract of Panax notoginseng (PNG) against chronic ethanol‐induced hepatotoxicity. Fifty mice were divided into ﬁve equal groups with 10 in each group. Group 1 (control) received saline, whereas group 2 received ethanol (70%, 0.1 mL, p.o.) once daily for 4 weeks, which induced hepatotoxicity, manifested biochemically by a signiﬁcant elevation of serum enzyme activities, such as SGOT and SGPT. Hepatotoxicity was further evidenced by a signiﬁcant increase in the hepatic lipid peroxidation measured. Groups 3–5 were administered a hot water extract of PNG at doses of 10, 25 and 50 mg/kg 2 weeks after initiating oral administration of ethanol, for a further 2 weeks. PNG ameliorated the rise in serum sGOT and sGPT induced by chronic ethanol administration. The mice were killed after PNG administration. In a separate study, PNG inhibited the lipid peroxidation in the mouse liver homogenate induced by ethanol in a dose‐dependent manner. The ﬁndings indicate that PNG is an efﬁcient cytoprotective agent against chronic ethanol‐induced hepatotoxicity, possibly through inhibition of the production of oxygen‐free radicals that cause lipid peroxidation. Copyright © 2003 John Wiley & Sons, Ltd.
Fenugreek affects the activity of β‐glucuronidase and mucinase in the colon
Authors: Devasena T. , Menon Venugopal P.
Published: October 2003

The effect of fenugreek seeds on the activities of β‐glucuronidase and mucinase during 1,2‐dimethylhydrazine (DMH)‐induced colon carcinogenesis in rats was studied. Rats were given a weekly subcutaneous injection of DMH at a dose of 20 mg/kg body weight, for 15 weeks. Fenugreek seed powder was weighed depending upon the weight of individual rats and incorporated in the powdered pellet diet at a dose of 2 g/kg body weight. After an experimental period of 30 weeks the activity of β‐glucuronidase signiﬁcantly increased in the colon, intestine, liver and colon contents in DMH administered rats when compared to an untreated control group. Increase in β‐glucuronidase may increase the hydrolysis of carcinogen‐glucuronide conjugate, liberating carcinogen and/or co‐carcinogen within the colonic lumen. Inclusion of fenugreek seed powder in the diet signiﬁcantly decreased the activity of β‐glucuronidase in all the tissues studied. This may prevent the free carcinogens from acting on colonocytes. Mucinase helps in hydrolysing the protective mucin. Mucinase activity was increased in the colon content and fecal content of animals given DMH when compared to control, while the activity was signiﬁcantly reduced in animals given DMH + fenugreek when compared to animals given DMH only. Our study shows that supplementation of fenugreek seeds in the diet inhibits colon carcinogenesis, by modulating the activities of β‐glucuronidase and mucinase. The beneﬁcial effect may be attributed to the presence of ﬁbre, ﬂavonoids and/or saponins. Copyright © 2003 John Wiley & Sons, Ltd.
Antiasthmatic property of polyherbal preparation E‐721 B
Authors: Shah Gaurang B. , Parmar N. S.
Published: October 2003

E‐721B and its aqueous extract were studied for its antiasthmatic effect in various experimental models using rats and guineapigs. E‐721B produced signiﬁcant and dose‐dependent inhibition of peritoneal mast‐cell degranulation induced by compound 48/80 and egg‐albumin in sensitised rats. The inhibition was comparable to that with disodium cromoglycate, ketotifen, and prednisolone. E‐721B administered 2 h before the experiment and once daily for seven days signiﬁcantly increased the preconvulsion time of acetylcholine and histamine aerosol‐induced bronchospasm. It also signiﬁcantly reduced mortality in guineapigs produced by egg albumin‐induced anaphylactic shock and also reduced bronchoalveolar ﬂuid eosinophil count in the same animals. E‐721B signiﬁcantly inhibited the acetylcholine and histamine‐induced contraction of different isolated smooth muscle preparations from rats and guineapigs. Contrary to these ﬁndings E‐721B produced dose‐dependent contraction of the rat anococcygeus muscle which was blocked by prazosin. Thus our observations establish the antiasthmatic potential of this herbal formulation. Copyright © 2003 John Wiley & Sons, Ltd.