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The kinetochore is a supramolecular protein complex assembled on the chromosomes, essential for faithful segregation of the genome during cell divisions. More than 100 proteins are known to constitute the eukaryotic kinetochore architecture, primarily identified using non-plant organisms. A majority of them are fast evolving and are under positive selection. Thus, functional characterization of the plant kinetochore proteins is limited as only a few conserved orthologs sharing sequence similarities with their animal counterparts have been examined. Here, we report the functional characterization of the Arabidopsis thaliana homolog of the yeast NNF1/human PMF1 outer kinetochore protein and show that it has both kinetochore and non-kinetochore functions in plant growth and development. Knockout of NNF1 causes embryo lethality implying its essential role in cell division. AtNNF1 interacts with MIS12 in a Y2H and co-immuno pull down assay, confirming it as one of the constituents of the plant MIS12 complex. GFP-NNF1 localizes to the kinetochore, rescuing the embryo lethal nnf1-1-/- phenotype, but the rescued plants (GFP-NNF1nnf1-/- ) are dwarf displaying hypomorphic phenotypes with no evidence of mitotic or meiotic segregation defects. GFP-NNF1nnf1-/- dwarf plants have reduced levels of endogenous polyamines, which are partially rescued to WT upon exogenous application of polyamines. Mutations in the putative leucine zipper binding motif of NNF1 gave rise to a dominant-negative tall plant phenotype reminiscent of constitutive gibberellin action. These contrasting hypomorphic dwarf and anti morphic tall phenotypes facilitated us to attribute a moonlighting role for Arabidopsis NNF1 affecting polyamine and gibberellin metabolism other than its primary role in kinetochores.

A machine learning method based on spatial convolution to capture complex spatial precipitation patterns is proposed to identify and reduce biases affecting predictions of a dynamical model. The method is based on a combination of a classification and dual regression model approach using modified U-Net convolutional neural networks (CNN) to post-process daily accumulated precipitation over the US west coast. In this study, we leverage 34 years of high resolution deterministic Western Weather Research and Forecasting (West-WRF) precipitation reforecasts as training data for the U-Net CNN. The data is split such that the test set contains 4 water years of data that encompass characteristic west coast precipitation regimes: El Niño, La Niña, and dry and wet El Niño/Southern Oscillation (ENSO-neutral) water years. On the unseen 4-year data set, the trained CNN yields a 12.9-15.9% reduction in root mean square error (RMSE) and 2.7-3.4% improvement in Pearson correlation (PC) over West-WRF for lead times of 1-4 days. Compared to an adapted model output statistics correction, the CNN reduces RMSE by 7.4-8.9% and improves PC by 3.3-4.2% across all events. Effectively, the CNN adds more than a day of predictive skill when compared to West-WRF. The CNN outperforms the other methods also for the prediction of extreme events, which we define as the top 10% of events with the greatest average daily accumulated precipitation. The improvement over West-WRF’s RMSE/PC for these events is 19.8-21.0%/4.9-5.5% and MOS’s RMSE/PC is 8.8-9.7%/4.2-4.7%. Hence, the proposed U-Net CNN shows significantly improved forecast skill over existing methods, highlighting a promising path forward for improving precipitation forecasts.

The 21st century has witnessed three outbreaks of coronavirus (CoVs) infections caused by severe acute respiratory syndrome (SARS)‐CoV, Middle East respiratory syndrome (MERS)‐CoV, and SARS‐CoV‐2. Coronavirus disease 2019 (COVID‐19), caused by SARS‐CoV‐2, spreads rapidly and since the discovery of the first COVID‐19 infection in December 2019, has caused 1.2 million deaths worldwide and 226,777 deaths in the United States alone. The high amino acid similarity between SARS‐CoV and SARS‐CoV‐2 viral proteins supports testing therapeutic molecules that were designed to treat SARS infections during the 2003 epidemic. In this review, we provide information on possible COVID‐19 treatment strategies that act via inhibition of the two essential proteins of the virus, 3C‐like protease (3CLpro) or papain‐like protease (PLpro)., Highlights This highlights the importance of 3CLpro and PLpro as theraputic targets for drug design and development of SARS‐CoV‐2 inhibitors to prevent COVID‐19.

Background The present study reports the functionalization of multiwalled carbon nanotubes (MWCNTs) with vinyl groups through nitric acid oxidation along with reaction with allylamine. MWCNTs based imprinted polymer (MWCNT-MIP) were synthesized by means of methacrylic acid (MAA) as the monomer, trimethylol propane trimethacrylate (TRIM) as the cross linker, α, αʹ-azobisisobutyronitrile (AIBN) as the initiator and chlorpyrifos (CPF), an organophosphate pesticide molecule as the template. Results The prepared material was characterized by means of FTIR, XRD and SEM analysis. The competence of MWCNT-MIP to adsorb CPF from aqueous solutions was calculated. The maximum adsorption was found to be at pH 7.0 and adsorption capability attained saturation in 3 h. The kinetic information was found to follow pseudo-second-order model, indicating chemisorption. The strong conformity of equilibrium data with the Langmuir isotherm model confirms the monolayer coverage of CPF on the MWCNT-MIP surface. The maximum adsorption ability based on the Langmuir isotherm model was found to be 38.14 mg g−1 at 30°C. The spent adsorbent was successfully regenerated by means of 0.1 mol L−1 CH3COOH. Conclusion Analysis revealed that MWCNT-MIP could be a useful substance for the removal of CPF from aqueous solutions. © 2013 Society of Chemical Industry

The present work describes a novel method for the synthesis of silver polymer nanocomposite for the delivery of amoxicillin (AMO). Silver nanoparticles (AgNPs) were synthesized with chitosan and silver nitrate. The reaction parameters were optimized. Three-dimensional polymeric networks were synthesized by simple free-radical graft copolymerization. UV–visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, SEM, atomic force microscopy, dynamic light scattering, and zeta potential analysis were used for the complete characterization of the samples. Swelling studies and swelling factors were evaluated. In vitro release of AMO and AgNPs at physiological pHs was analyzed using the Peppas kinetic model to explain the drug delivery mechanism. Cytotoxicity, free-radical scavenging, and antibacterial activities were analyzed. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43479.

BACKGROUND: The main aim of this study is to determine the sorptive potential of a novel anion exchanger, Fe(III)-coordinated amino-functionalized poly(glycidylmethacrylate)-grafted TiO2-densified cellulose (AM-Fe-PGDC) for arsenic(V) removal from aqueous solutions by batch technique. RESULTS: The adsorbent was characterized using infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, thermogravimetry and potentiometric titrations. The effective pH for removal was 6.0. The adsorption rate was influenced by initial metal ion concentration and contact time. The equilibrium was achieved within 1.5 h and follows a pseudo-second-order kinetic model. The adsorption capacity for As(V) calculated using the Langmuir isotherm equation was 105.47 mg g−1. The AM-Fe-PGDC developed was used to remove As(V) from simulated groundwater. Regeneration experiments were attempted for four cycles using 0.1 mol L−1 NaCl solution. CONCLUSION: It was found that AM-Fe-PGDC is very efficient for the removal of As(V) from aqueous solutions. © 2012 Society of Chemical Industry

The performance of an anion exchanger prepared from banana stem (BS), a lignocellulosic residue for the removal of As(III) from aqueous solutions has been evaluated in this study. The adsorbent (BS-DMAHP) containing dimethylaminohydroxypropyl (DMAHP) functionality was prepared by the reaction of BS with epichlorohydrin and dimethylamine followed by treatment with hydrochloric acid to convert it into the chloride form of the anion exchanger. The adsorbent characterization was done with the surface area analyzer, Fourier transform infrared spectroscopy (FTIR), and potentiometric titrations. Adsorption equilibrium study was conducted with a concentration range of 10–300 mg/L, for As(III). The Langmuir isotherm model was found to be the best fit model. The maximum adsorption capacity was found to be 65.11 mg/g. Adsorption has been found to be endothermic and follows second-order reversible kinetics. The removal efficiency of BS-DMAHP was also compared with commercially available amine functionalized weak base anion exchanger, Duolite A-7. Regeneration studies were also conducted to evaluate the reusability of the adsorbent. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

BACKGROUND: Environmental pollution and its abatement have attracted much attention for some time. The problem of removing pollutants from water and wastewater has grown along with rapid industrialization. Formaldehyde polymerized banana stem (FPBS) having sulphonic acid groups was investigated as an adsorbent for cadmium(II) removal from aqueous solutions. RESULTS: The outstanding function of the adsorbent was demonstrated at pH 9.0. The adsorption efficiency of FPBS was compared with BS and results showed that FPBS was two times more effective than BS for cadmium(II) removal. Maximum recoveries of 97.3 and 90.3% for 10 and 25 mg L−1 initial concentrations were obtained at pH 9.0. Kinetic studies revealed that adsorption occurred in two stages: external mass transport in the first stage and intra-particular diffusion in the second stage. Adsorption was found to be rapid and equilibrium was attained in 60 min. Among the various desorbing agents tested, 99.2% cadmium recovery was achieved with 0.1 mol L−1 HCl. CONCLUSIONS: The uptake efficiency of cadmium(II) by FPBS was determined. Repeated adsorption-desorption study showed that FPBS can be used as an adsorbent for the removal and recovery of Cd(II) from aqueous solutions. Copyright © 2012 Society of Chemical Industry

A novel poly(methacrylic acid)-grafted-cellulose/bentonite (Cellu-g-PMAAc/Bent) superabsorbent composite was prepared through graft copolymerization reaction among cellulose, methacrylic acid, and bentonite in the presence of N,N′-methylenebisacrylamide as a crosslinker and potassium peroxydisulphate as an initiator. The structural and morphological characteristics of the graft copolymer were determined using Fourier transform infrared spectra, scanning electron microscope-energy dispersion analysis, and X-ray diffraction. The effectiveness of the Cellu-g-PMAAc/Bent, as adsorbent for the removal and recovery of uranium(VI) from aqueous media, was studied. The effects of pH, contact time, and initial sorbate concentration were studied to optimize the conditions for maximum adsorption. The adsorption process, which was pH dependent, shows maximum removal (>99.0%) at pH 6.0. Kinetic study showed that 180 min of contact at 100 mg/L could adsorb about 99.2% of U(VI) onto Cellu-g-PMAAc/Bent. A pseudosecond-order kinetic model successfully described the kinetics of sorption of U(VI). Adsorption equilibrium data were correlated with the Langmuir, Freundlich, and Redlich–Peterson isotherm models. The best fit was obtained with Freundlich model. Desorption of U(UI) was studied by using 0.1M HCl. Adsorption/desorption for more than six cycles showed the possibility of repeated use of this graft copolymer for the recovery of U(VI) from aqueous solutions. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Adsorptive removal of EDTA (ethylenediaminetetraacetic acid) from aqueous solution was studied using steam pyrolyzed activated carbon. Rubber wood sawdust, obtained from a local timber facility at Kodangavila, Trivandrum, Kerala, India was used as the precursor for the production of the activated carbon. Batch adsorption experiments were employed to monitor and optimize the removal process. The experimental parameters, i. e., solution pH, agitation time, initial EDTA concentration and adsorbent dosage, affecting the adsorption of EDTA onto sawdust activated carbon (SDAC) were optimized. The inner core mechanism for the interaction between EDTA and SDAC, which resulted in the adsorption process, was also discussed. The change in amount of EDTA adsorbed onto SDAC and CAC (commercial activated carbon) was compared over a wide range of pH (2.0–8.0). The maximum removal of EDTA took place in the pH range of 4.0–6.0 for SDAC and 5.0–5.5 for CAC, which demonstrates the effectiveness of the former adsorbent. Kinetic as well as equilibrium studies were performed to determine the rate constant and adsorption capacity, respectively. The adsorption kinetic data was fitted with pseudo-first-order kinetics and the equilibrium data was shown to follow the Langmuir isotherm model. These observations explain the formation of a monolayer of EDTA on the surface of SDAC as confirmed by the slow approach to equilibrium after 4 h of contact time. The adsorption capacity of SDAC for the removal of EDTA was 0.526 mmol/g and is seen to be greater than that of CAC and other reported adsorbents (0.193–0.439 mmol/g). Finally, it is clear that the production of steam pyrolyzed activated carbon in the presence of K2CO3 greatly enhanced EDTA removal and resulted in a product with possible commercial value for wastewater treatment strategies.

This study concerns with the development of a new adsorbent, iron(III) complex of an amino-functionalized polyacrylamide-grafted coconut coir pith (CP), a lignocellulosic residue, for Cr(VI) in water and industry effluents. The adsorbent (AM-Fe-PGCP) was characterized by FTIR, EDS, Mossbauer, surface area analyzer, TG/DTG, and potentiometric titration. The effects of contact time, initial sorbate concentration, pH, dose of adsorbent, and temperature on Cr(VI) adsorption were studied to optimize the conditions for maximum adsorption. The kinetics of sorption was investigated using pseudo-first-order and pseudo-second-order rate equations with the later giving a better fit to the experimental data. The mechanism of sorption was found to be film diffusion controlled. The Langmuir isotherm model yields a much better fit than the Freundlich and Dubinin–Radushkevich models with maximum adsorption capacity of 142.76 mg/g at 30°C. Simulated industry wastewater sample was treated with AM-Fe-PGCP to demonstrate its efficiency in removing Cr(VI) from wastewater. The alkali treatment (0.1M NaOH) and re-introduction of Fe3+ lead to a reactivation of the spent adsorbent and can be reused through many cycles of water treatment and regeneration without any loss in the adsorption capacity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

The present investigation was undertaken to evaluate the effectiveness of a new adsorbent prepared from coconut coir pith (CP), a coir industry-based lignocellulosic residue in removing metal ions from aqueous solutions. The adsorbent (PGCP-COOH) having a carboxylate functional group at the chain end was prepared by grafting polyacrylamide onto CP using potassium peroxydisulphate as an initiator and in the presence of N,N′-methylenebisacrylamide as a crosslinking agent. The adsorbent was characterized by infrared (IR) spectroscopy, thermogravimetry (TG), X-ray diffraction (XRD) patterns, scanning electron microscopy (SEM), and potentiometric titration. The adsorbent exhibits very high adsorption potential for the removal of Pb(II), Hg(II), and Cd(II) ions from aqueous solutions. The optimum pH range for metal ion removal was found to be 6.0–8.0. The adsorption process follows a pseudo-second-order kinetic model. The adsorption capacities for Hg(II), Pb(II), and Cd(II) calculated using the Langmuir isotherm equation were 254.52, 189.49, and 63.72 mg g−1, respectively. Adsorption isotherm experiments were also conducted for comparison with a commercial carboxylate form cation exchanger. Different industry wastewater samples were treated by the PGCP-COOH to demonstrate its efficiency in removing heavy metals from wastewater. The reusability of the PGCP-COOH was also demonstrated using 0.2M HCl. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3670–3681, 2007

This study examined the effectiveness of a new adsorbent prepared from banana (Musa paradisiaca) stalk, one of the abundantly available lignocellulosic agrowastes, in removing Pb(II) and Cd(II) ions from aqueous solutions. The adsorbent (PGBS-COOH) having a carboxylate functional group at its chain end was synthesized by graft copolymerization of acrylamide on to banana stalk, followed by functionalization. Batch adsorption experiments were carried out as a function of solution pH, ionic strength, contact time, metal concentration, adsorbent dose and temperature. A pH range of 5.5–8.0 was found to be effective for the maximum removal for both Pb(II) and Cd(II). Metal uptake was found to decrease with increase in ionic strength due to the expansion of the diffuse double layer and, more importantly, the formation of some chloro complexes (since NaCl was used in the adjustment of ionic strength), which do not appear to be adsorbed to the same extent as cations [M2+ and M(OH)+]. The kinetic studies showed that an equilibrium time of 3 h was needed for the adsorption of Pb(II) and Cd(II) on PGBS-COOH and adsorption processes followed a pseudo-second-order equation. The Langmuir isotherm model fitted the experimental equilibrium data well. The maximum sorption capacity for Pb(II) and Cd(II) ions was 185.34 and 65.88 mg g−1, respectively, at 30 °C. The thermodynamic parameters such as changes in free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) were derived to predict the nature of adsorption. The isosteric heat of adsorption was found to be independent of surface coverage. Adsorption experiments were also conducted using a commercial cation exchanger, Ceralite IRC-50, for comparison. Synthetic wastewater samples were treated with the adsorbent to demonstrate its efficiency in removing Pb(II) and Cd(II) ions from industrial wastewaters. Acid regeneration was tried for several cycles with a view to recovering the sorbed metal ions and also restoring the sorbent to its original state. Copyright © 2005 Society of Chemical Industry

The sawdust (SD) waste generated in the timber industry was converted to a low-cost activated carbon (SDAC) using a simpler and cheaper activation process, single-step steam pyrolysis activation. The possibility of utilizing SDAC for the removal of lead (Pb(II)) in the absence of ligands and nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA) chelated Pb(II) complexes from the liquid phase was examined and the results were compared with those for commercial activated carbon (CAC). SDAC shows a high adsorption capacity for Pb(II) and Pb(II) chelates compared with CAC. The extent of adsorption of Pb(II) and Pb(II) chelates on activated carbons was found to be a function of solution pH and species distribution of Pb(II) and Pb(II) chelates. The optimum pH range for the removal of Pb(II) in the absence of ligands by SDAC was 6.5–8.0, whereas its maximum removal by CAC was observed at pH 6.5. In the presence of ligands, the extent of Pb(II) adsorption was enhanced in the pH range 2.0–5.0 and was reduced significantly in the pH range 6.0–8.0. The maximum uptake of Pb(II) chelates for both carbons was observed at pH 5.0. Kinetic models such as pseudo-first-order, pseudo-second-order and pore diffusion were tested to investigate the adsorption mechanism. Batch kinetic studies showed that the adsorption of Pb(II) from aqueous solutions with and without ligands could be best described by a psuedo-first-order model for both carbons. The effect of pH on the adsorption isotherms of Pb(II) and Pb(II) chelates was also investigated. The applicability of the Langmuir and Freundlich isotherms, established for various initial concentrations of the adsorbate and for different pH values, was tested at 30 °C. Copyright © 2003 Society of Chemical Industry

Iron(III)-loaded carboxylated polyacrylamide-grafted sawdust was investigated as an adsorbent for the removal of phosphate from water and wastewater. The carboxylated polyacrylamide-grafted sawdust was prepared by graft copolymerization of acrylamide and N,N′-methylenebisacrylamide onto sawdust in the presence of an initiator, potassium peroxydisulfate. Iron(III) was strongly attached to the carboxylic acid moiety of the adsorbent. The adsorbent material exhibits a very high adsorption potential for phosphate ions. The coordinated unsaturated sites of the iron(III) complex of polymerized sawdust were considered to be the adsorption sites for phosphate ions, the predominating species being H2PO ions. Maximum removal of 97.6 and 90.3% with 2 g L−1 of the adsorbent was observed at pH 2.5 for an initial phosphate concentration of 100 and 250 μmol L−1, respectively. The adsorption process follows second-order kinetics. Adsorption rate constants as a function of concentration and temperature and kinetic parameters, such as ΔG±, ΔH±, and ΔS±, were calculated to predict the nature of adsorption. The L-type adsorption isotherm obtained in the sorbent indicated a favorable process and fitted the Langmuir equation model well. The adsorption capacity calculated by the Langmuir adsorption isotherm gave 3.03 × 10−4 mol g−1 of phosphate removal at 30°C and pH 2.5. The isosteric heat of adsorption was also determined at various surface loadings of the adsorbent. The adsorption efficiency toward phosphate removal was tested using industrial wastewater. Different reagents were tested for extracting phosphate ions from the spent adsorbent. About 98.2% of phosphate can be recovered from the adsorbent using 0.1M NaOH. Alkali regeneration was tried for several cycles with a view to recover the adsorbed phosphate and also to restore the adsorbent to its original state. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2541–2553, 2002

Superabsorbent polymer composites (SAPCs) are very promising and versatile materials for biomedical applications. This study concentrates on the development of novel cellulose-based SAPC, Poly(acrylic acid-co-acrylamide-co−2-acrylamido-2-methyl-1-propanesulfonic acid)-grafted nanocellulose/poly(vinyl alcohol) composite, P(AA-co-AAm-co-AMPS)-g-NC/PVA, as a potential drug delivery vehicle. Amoxicillin was selected as a model drug, which is used for the treatment of Helicobacter pylori induced peptic and duodenal ulcers. P(AA-co-AAm-co-AMPS)-g-NC/PVA was synthesized by graft copolymerization reaction, and FTIR, XRD, SEM, and DLS analyses were performed for its characterization. Equilibrium swelling studies were conducted to evaluate the stimuli-response behavior of the SAPC and found that equilibrium swelling was dependent on pH, contact time, temperature, ionic strength, concentration of crosslinker and PVA. Maximum drug encapsulation efficiency was found out by using different concentrations of amoxicillin. Drug release studies were carried out at simulated gastric and intestinal fluids and the release % was observed as maximum in intestinal fluids within 4 h. The drug release kinetics was investigated using Peppas' potential equation and follows non-Fickian mechanism at pH 7.4. Thus, the drug release experiments indicate that P(AA-co-AAm-co-AMPS)-g-NC/PVA would be a fascinating vehicle for the in vitro administration of amoxicillin into the gastrointestinal tract. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40699.

Zirconium pillared clay (PILC) was prepared using montmorillonite as the base clay. Adsorption of tannic acid (tannin) was studied by a batch equilibrium technique, as a function of adsorbate concentration, temperature, pH, agitation speed, particle size of the adsorbent and ionic strength. The process of uptake is governed by diffusion controlled first-order reversible rate kinetics. The higher uptake for the pH range 4.0–6.0 was attributed to external hydrogen bonding between phenolic-OH groups of tannin molecules and the hydrogen bonding sites on the clay. The removal of tannin by adsorption was found to be >99.0% depending on the initial concentration in the pH range of 4.0–6.0. The process involves both film and pore diffusion to different extents. The effects of solute concentration, temperature, agitation speed and particle size on the diffusion rate were investigated. Tannin uptake was found to increase with ionic strength due to the compression of diffuse double layers. The applicability of Langmuir and Freundlich isotherm models has been tested. The maximum adsorption capacity of PILC was found to be 45.8 µmol g−1 of clay and the affinity constant is 2.9 × 10−2 dm3 µmol−1 at 30 °C. Thermodynamic parameters such as ΔG °,ΔH ° and ΔS ° were calculated to predict the nature of adsorption. The isosteric enthalpies of adsorption were also determined and found to decrease with increasing surface coverage. Regeneration with hot water (60 °C) has been investigated for several cycles with a view to recovering the adsorbed tannin and also restoring the sorbent to its original state. Copyright © 2001 Society of Chemical Industry

Graft copolymerization of acrylamide onto coconut husk (CH), initiated by the ferrous ammonium sulfate/H2O2 redox initiator system, was studied. To determine the optimum conditions of grafting, the effect of the concentrations of ferrous ammonium sulfate, the monomer, and H2O2 and the time and temperature on percentage of the graft yield was studied. A new adsorbent media having a carboxylate functional group was synthesized by the surface modification of polymer-grafted coconut husk (PGCHCOOH). The mechanism of graft polymerization and surface functionalization is proposed. The material exhibits a very high adsorption potential for Hg(II). The sorption of Hg(II) was found to be dependent on the contact time, concentration, pH, and temperature. Maximum removal of 99.4% with 2 g/L of the sorbent was observed at 125 μmol L−1 Hg(II) concentration at pH 6.0. The slow step which determines the rate of exchange of Hg(II) ions is diffusion through the adsorbent particles. The diffusion coefficients, energy of activation, and entropy of activation were calculated and used to determine the theoretical behavior of the sorption process. The applicability of the Langmuir isotherm established the endothermic character of the adsorption. Acid regeneration was tried for several cycles with a view to recover the adsorbed metal ions and also to restore the sorbent to its original state. The adsorbent efficiency toward Hg(II) removal was tested using synthetic and chloralkali industry wastewaters. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 1261–1269, 2000