bluuebunny/crossref_metadata_2025 huggingface dataset:
Antimony biomethylation by the wood rotting fungus Phaeolus schweinitzii
Authors: Andrewes Paul , Cullen William R. , Polishchuk Elena , Reimer Ken J.
Published: August 2002

The wood rotting fungus, Phaeolus schweinitzii, efficiently transforms the antimony(III) compounds potassium antimony tartrate and antimony trioxide to nonvolatile dimethylantimony and trimethylantimony species. The organoantimony species were detected in potato dextrose broth media samples by using hydride generation–gas chromatography–atomic absorption spectroscopy (HG–GC–AAS). The average concentrations of trimethylantimony species after 40 days incubation with potassium antimony tartrate were approximately 35 μg, 155 μg and 520 μg Sb/l, for substrate concentrations of 10 mg, 100 mg and 1000 mg Sb/l respectively. Thus, the maximum yield of trimethylantimony species was approximately 0.4%. When antimony trioxide (saturated solution, 4 mg Sb/l) was used as a substrate, the average concentration of trimethylantimony species was 150 μg Sb/l after 40 days. The HG–GC–AAS response for the dimethylantimony species was less than that for the trimethylantimony species; however, quantification was not possible because of the lack of an appropriate standard. In comparison, cultures of P. schweinitzii incubated with 1 mg As/l as sodium arsenite contained approximately 200 μg As/l as trimethylarsenic species, i.e. 20% yield. Biomethylation of antimony(V) was inefficient: cultures contained only 3 μg Sb/l as trimethylantimony species after incubation with 100 mg Sb/l as potassium hexahydroxyantimonate. No organoantimony species were detected in control cultures that contained only medium and inorganic antimony compounds. The identities of the organoantimony species were confirmed by using GC–Mass Spectrometry.
Magnetic nanocomposites from nitrogen base polymers
Authors: Millan A. , Palacio F.
Published: August 2002

Polymers containing nitrogen basic groups can be used in the preparation of metal oxide–polymer nanocomposites thanks to the capacity of the N atoms to coordinate iron ions. In this work, nanocomposites consisting of iron oxide and poly(4‐vinylpyridine) polymer have been prepared. The materials are produced by suspending beads of the polymer in a metal salt solution. Superparamagnetic nanoparticles of metal oxides or hydroxides are grown within the polymer–metal complex gel by drying in an oven. The reaction of the polymer with the metal solution takes place by a surface reaction mechanism. Contrary to cross‐linked polymers, this mechanism of reaction allows the production of materials with different nanoparticle sizes. Copyright © 2001 John Wiley & Sons, Ltd.
Optothermal properties of fiber morphology on nylon 66 fibers due to annealing and drawing processes
Authors: Fouda I. M.
Published: August 2002

The changes produced by the effects of annealed and drawn fibers on the microstructure and macrostructure of nylon 66 fibers are considered. The optical properties and strain produced in nylon 66 fibers under different conditions are measured interferometrically at room temperature. Structural parameters are calculated such as the average work per chain, the work per unit volume, the reduction in entropy due to elongation, and the work stored in the body as strain energy. The evaluation of the density aided the calculation of the crystallinity, the mean square density fluctuation, the isotropic refractive index, the harmonic mean polarizability of the dielectric, and the harmonic mean specific refractivity. In addition, the resulting data are utilized to calculate the optical stress coefficient and the optical configuration and to apply the Mooney–Rivlin equation to determine its constants. Also, the number of crystals per unit volume and the average orientation angle for uniaxial stretching are calculated by the extension ratio. The relations between the optical, mechanical, and thermal changes with different parameters are given for the studied fibers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 916–928, 2002; DOI 10.1002/app.10107
Graft copolymerization studies. III. Methyl methacrylate onto polypropylene and polyethylene terephthalate
Authors: Dokolas Peter , Qiao Greg Guanghua , Solomon David H.
Published: August 2002

The tert‐butoxy radical‐facilitated grafting of methyl methacrylate (MMA) onto commercial polypropylene (PP) pellets and fiber was investigated in heterogeneous conditions similar to practical systems. Free‐radical grafting of several other monomers onto PP fiber was also investigated. Also, preliminary data from the grafting of MMA onto poly(ethylene terephthalate) pellets is presented. The PP‐graft‐PMMA residues were detected by solid‐state 13C‐NMR and photoacoustic IR spectroscopy. There was a good correlation between the degree of grafting (DG) determined from these spectroscopic techniques and the results from gravimetric methods. A maximum grafting efficiency of over 50% was found, whereas DG (20%) remained constant at various PP pellet, initiator, and monomer concentrations. However, at relatively low PP fiber concentrations, the DG was 27%; the increase was most likely due to the greater surface area of the fiber. There was also a reduction in DG (14%) at relatively low initiator concentrations. The reaction conditions were altered to favor grafting by the addition of more polymer substrate. When the ratio of tert‐butoxy radicals to PP was decreased, more of the substrate remained unmodified, and empirical calculations showed the formation of grafts with up to 40 monomer units. At high initiator concentrations, calculations showed that the graft residues were 1–2 units long. Therefore, variation of the polymer, initiator, and monomer concentrations was shown to have a significant effect on grafting. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 898–915, 2002
Characterization of UV‐curable reactive diluent containing quaternary ammonium salts for antistatic coating
Authors: Hong J. W. , Kim H. K. , Yu J. A. , Kim Y. B.
Published: August 2002

Reactive diluent with quaternary ammonium salts (RDQ) for UV‐curable antistatic coating was synthesized by reacting glycidyl methacrylate (GMA) and piperazin with dropping the methansulfonic acid. In order to compare the curing behavior of RDQ with commercial monomers, the photopolymerization of RDQ, 1,6‐hexandiol diacrylate (HDDA) and 1,6‐hexandiol dimethacrylate (HDDMA) were studied by using real‐time IR spectroscopy. Surface properties such as surface resistance, pencil hardness, and solvent resistance of the cured films containing RDQ were investigated. When used as a reactive diluent in the UV‐curable coating formulation, the RDQ imparted excellent antistatic properties to the final material. The results of an Fourier transform infrared/attenuated total reflectance (FTIR/ATR) depth profile analysis show that RDQ molecules are more concentrated near the surface within a micrometer‐thick layer, indicating that existence of the ionic components in the surface layer is responsible for antistatic property. Film cured from the formulation containing 12 wt % of RDQ showed the best mechanical properties with reasonable surface properties. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 132–137, 2002; DOI 10.1002/app.10273
Carbon‐13 solution and solid‐state NMR investigation of alpha‐methylstyrene‐co‐acrylonitrile
Authors: Nogueira Regina F. , Tavares Maria Inês B.
Published: August 2002

Nuclear magnetic resonance spectroscopy (NMR) gave information on the behavior of alpha‐methylstyrene‐co‐acrylonitrile. The comonomer sequence distribution in the copolymer and the depolymerization process were detected by solution analysis. The solid‐state NMR investigation showed that 13C routine spectra such as MAS and CPMAS allowed one to obtain information on the molecular domains of chains and also permitted evaluation of the domains' mobility. In this case, the mobile domain was formed by alpha‐methylstyrene (AMS). The variable contact time and the proton spin‐lattice relaxation time in the rotating‐frame parameter were determinant factors to evaluate the dynamic molecular behavior and the homogeneity of the comonomer distribution along the copolymer chains. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 138–143, 2002; DOI 10.1002/app.10275
Preparation and structural characterization of water‐soluble O‐hydroxypropyl chitin derivatives
Authors: Park In Kyu , Park Young Hwan
Published: August 2002

Water‐soluble hydroxypropyl chitin (HPC) derivatives were prepared by the reaction of chitin with propylene oxide in homogeneous conditions using a dimethylacetamide/5% lithium chloride solvent system. The reaction conditions for a proper substitution of the hydroxypropyl group were an 80°C reaction temperature, 24‐h reaction time, and 48‐h aging time. 1H‐NMR and 13C‐cross‐polarization/magic angle spinning NMR spectroscopy were used for determining the substitution value and reaction site of substitution. It was found that the substitution reaction occurred mainly at the C6OH group in the chitin molecules and water‐soluble chitin derivatives could be obtained at a substitution value higher than 0.35, which is known as a critical substitution value. X‐ray diffraction analysis and FTIR spectroscopy showed that the structural characteristics of HPC derivatives were dependent on the substitution value. As the substitution value of the HPC derivative increased the α‐chitin crystal structure changed to the water‐soluble β‐chitin form in higher substitution values. Differences in the interchenic hydrogen bonding, interplanar spacing of the crystal lattice plane, and crystallinity can explain the structural changes upon substitution. The thermal decomposition temperature was also related to the characteristics of the crystalline structure, depending on a critical substitution value. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2624–2632, 2001
Abatement of heavy metals and softening of hard water by the CoAlPO4‐5/polysulfone membrane
Authors: Lin Shiow‐Shyung , Chen Shih‐Hsiung , Chang Chia‐Yan , Chang Dong‐Jang , Chen Chia‐Chrn
Published: August 2002

To improve the membrane, if CoAlPO4‐5 was appropriately added, it could increase the rejection rate of metal ions compared with the PSf membrane. Besides, penetration rate would also increase, and the pressure applied could be lowered when the improved membrane was used. The optimum amount of CoAlPO4‐5 added for Co : Al : P = 0.1 : 0.92 : 1.0 is about 5 wt %, while for the Co : Al : P = 0.08 : 0.93 : 1.0, this optimum value would shift toward a higher wt % because the latter has less active sites per unit weight of CoAlPO4‐5. The hydrated radius of metal ion had great influence on the rejection rate. The larger the radius, for example, that of the +3 valence cations, the higher the rejection rate would exhibit, and the rate for Cd2+was much lower because its radius was the smallest one. Moreover, although incompatibility existed in the improved membrane and the variation of applied pressure was limited, durability of this membrane under the operating conditions was good. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2768–2773, 2001
Swelling–deswelling behavior of poly(acrylamide‐co‐maleic acid) hydrogels
Authors: Bajpai S. K.
Published: August 2002

In this study the poly(acrylamide‐co‐maleic acid) hydrogels containing small amounts of maleic acid have been synthesized, and the effect of pH, ionic strength, and nature of counterions on the equilibrium water uptake has been investigated. The incorporation of small amount of maleic acid results in the transition of swelling mechanism from Fickian to non‐Fickian. The equilibrium mass swelling has been found to increase with pH of the swelling medium while increase in ionic strength causes a decrease in the swelling. The amount of maleic acid present in the hydrogel affects the swelling behavior in rather an unusual way. With lower acid contents, the equilibrium mass swelling increases while higher concentrations of maleic acid cause a decrease in the degree of swelling. The hydrogels have been found to undergo a number of swelling–deswelling cycles when pH of the swelling medium changes from 8.0 to 2.0. Hydrogels require more time to deswell compared to the time required for swelling, which has been explained on the basis of the fact that gels follow different mechanisms for the two processes. Various swelling parameters such as equilibrium mass swelling, diffusion coefficient, intrinsic diffusion coefficient, swelling exponent, etc., have been evaluated. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2782–2789, 2001
Electro‐induced polymerization of acrylamide initiated by the potassium permanganate–titriplex VI redox system
Authors: Saraç A. Sezai̇ , Soydan A. Bahattin , Bülbül Hayal
Published: August 2002

The polymerization of acrylamide (AAm) was carried out with a potassium permanganate–Titriplex VI redox initiator system with and without electrolysis. Because of the high metal‐ion concentration in general, low‐molecular‐weight polymers were obtained (weight‐average molecular weight = 2600–4000). The effect of potassium permanganate and AAm concentrations and temperature on the polymerization yield was studied and compared with results obtained under the same experimental conditions used for electrolysis. The results of Fourier transform infrared spectroscopy, atomic absorption spectrometry, and scanning electron microscopy (SEM) results are given. SEM micrographs of the polymer obtained by electrochemical methods exhibited smoother surfaces than those obtained by nonelectrolytic methods. In the absence of potassium permanganate, there was no polymerization under experimental conditions. A possible reaction mechanism is suggested. The electro‐induced system resulted in about a 50% increase in the yield. Manganese content in the electro‐induced and chemical polymerization systems were 2.7 and 8.2%, respectively, supporting the yield increase in the electro‐induced system. A graphite electrode was used and resulted in a high yield and a fibrous polymeric structure. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1526–1534, 2001
Melting behavior and crystallization kinetics of poly(butylene terephthalate‐co‐diethylene terephthalate) and poly(butylene terephthalate‐co‐triethylene terephthalate) copolyesters
Authors: Finelli Lara , Lotti Nadia , Righetti Maria Cristina , Munari Andrea
Published: August 2002

The melting behavior of poly(butylene terephthalate‐co‐diethylene terephthalate) and poly(butylene terephthalate‐co‐triethylene terephthalate) copolymers was investigated by differential scanning calorimetry after isothermal crystallization from the melt. Multiple endotherms were found for all the samples, and attributed to the melting and recrystallization processes. By applying the Hoffman‐Weeks' method, the equilibrium melting temperatures of the copolymers under investigation were obtained. Two distinct peaks in the crystallization exothermic curve were observed for all the samples. Both of them appeared at higher times than that of PBT, indicating that the introduction of a comonomer decreased the crystallization rate. The observed dependence of this latter on composition was explained on the basis of the content of ether–oxygen atoms in diethylene and triethylene terephthalate units, and of the different sizes of these units. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3545–3551, 2001
Cationized sawdust as ion exchanger for anionic residual dyes
Authors: Baouab Mohamed Hassen V , Gauthier Robert , Gauthier Hélène , El Baker Rammah Mohamed
Published: August 2002

Using the same procedure as recently described for cotton fiber, the preparation of cationized wood sawdust was performed by treating alkali sawdust with epoxy propyl trimethyl ammonium chloride (EPTMAC) in a nonaqueous medium (dimethylformamide, DMF). The fixation of ammonium groups onto sawdust was monitored by weight uptake, nitrogen content determination, and infrared spectroscopy. EPTMAC‐sawdust with a 0.5 wt % nitrogen content is then used as adsorbent for acid dyes (Acid Blue 25, Acid Yellow 99, Reactive Yellow 23, and Acid Blue 74). The adsorption capacity, determined by spectrometric measurement of the residual dye in the treated solution, decreases with increasing temperature. The modeling of the adsorption isotherms using Langmuir, Freundlich, and General relations allows the determination of isotherm constants. Globally, EPTMAC‐sawdust has a behavior similar to EPTMAC‐cotton, and its use for depollution of waste waters from dyeing industries presents advantages over cotton, such as a larger availability and a lower price. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 31–37, 2001
Graft copolymerization of methyl methacrylate onto sago starch using ceric ammonium nitrate and potassium persulfate as redox initiator systems
Authors: Fakhru'L‐Razi A. , Qudsieh Isam Y. M. , Yunus Wan Md Zin Wan , Ahmad Mansor B. , Rahman Mohamad Zaki Ab.
Published: August 2002

The graft copolymerization of methyl methacrylate (MMA) onto sago starch was carried out in aqueous media by different initiators of ceric ammonium nitrate (CAN) and potassium persulfate (PPS) and under a nitrogen gas atmosphere. Using CAN as an initiator, the maximum percentage of grafting (%G) was ascertained to be 246% at the following optimum conditions: a 70°C reaction temperature, a 2‐h reaction period, 2.0 mmol of CAN, 0.4 mmol of nitric acid, and 141 mmol of MMA. The maximum %G achieved with PPS as the initiator was 90%. The optimum conditions were a 50°C reaction temperature, a 1.5‐h reaction period, 47 mmol of monomer, and 1.82 mmol of PPS. The grafting of MMA onto sago starch was confirmed by the IR spectra of pure sago starch, MMA, and MMA grafted sago starch. This material may have application as a biodegradable plastic. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1375–1381, 2001
Microvasculature of the buffalo epididymis
Authors: Scala Gaetano , De Girolamo Paolo , Corona Mario , Pelagalli Gaetano Vincenzo
Published: August 2002

The microvasculature of the water buffalo (Bubalus bubalis) epididymis was investigated using light (LM), scanning electron (SEM), and transmission electron (TEM) microscopy techniques. SEM analysis of the buffalo epididymis showed fenestrations that occupied ovoid inside the endothelium of the postcapillary venules located in thecaput,corpus,andcauda. They varied in shape and dimension, but more importantly, they connected the venules of the blood vascular system to the capillaries of the peripheral lymphatic vascular system. Morphofunctional analysis of these connections suggests that the microvasculature of the buffalo epididymis plays a role in facilitating the circulation of biologically active substances, and the absorption and secretion processes necessary for the survival and maturation of spermatozoa. The lymphatic capillaries at the connection points formed a network of variously sized polygonal links. These capillaries then converged to form the precollector lymphatic vessels, which in turn converged with the larger vessels originating from the testis. It was further noted that in the capillary endothelium there were no fenestrations, and in the large veins there were manydiverticula. Thesediverticulaappear to play a role in the regulation of the seasonal variations of the blood reflux. In general, the microvascular architecture of the buffalo epididymis, particularly its connection to the lymphatic vascular system, appears to play an important role in the absorption and secretion processes of the epididymal epithelium. Anat Rec 266:58–68, 2002. © 2002 Wiley‐Liss, Inc.
Quantitation of the changes in vascularity during arthritis in the knee joint of a mouse with a digital image analysis system
Authors: Buma Pieter , Groenenberg Martin , Rijken Paul F.J.W. , Van Den Berg Wim B. , Joosten Leo , Peters Hans
Published: August 2002

Many joint and bone diseases are caused by, or associated with vascular changes. Particularly in rheumatoid arthritis, vascular sprouting of synovial vessels plays a major role in the generation of joint pathology. To assess the effects of pharmaceuticals that are designed to inhibit neovascularization, we developed a quantitative procedure to measure vascular changes in cross‐sections of the mouse knee joint during arthritic inflammation. Arthritis was induced in the knee joint of C57Black6 mice by a single subpatellar injection of methylated BSA after previous immunization. Total vascularity was visualized with a specific monoclonal rat anti‐mouse antibody (9F1). Functional vessels were detected with the fluorescent perfusion marker Hoechst 33342. The localization of Hoechst and the vascular marker 9F1 were analyzed in separate images with an automated digital image processing system. By combining the two images, total vascularity and the perfusion status of the vessels during arthritis could be established. The digital image system measures synovial area (SA), number of all blood vessels (NBV) and the number of perfused blood vessels (NpBV). From these parameters the percentage of perfused vessels (perfusion fraction; PF), the vessel density (VD = NBV/SA) and the density of perfused vessels (VDp = NpBV/SA) can be calculated. The measurements showed that the area of synovial tissue had increased during arthritis. Moreover, both the number of blood vessels (NBV) and the number of perfused vessels (NpBV) in the synovial area had increased significantly on Days 4 and 7 after arthritis induction. This procedure enabled quantitation of total vascularity and of functional blood vessels in cross‐sections of synovial tissue. It is expected to be a powerful tool, not only to analyze the effects of anti‐angiogenic therapies in animal models of arthritis, but could also be applicable to study vascular and perfusion changes in vascular related diseases of the skeleton. Anat Rec 262:420–428, 2001. © 2001 Wiley‐Liss, Inc.
Posterior maxillary (PM) plane and anterior cranial architecture in primates
Authors: McCarthy Robert C. , Lieberman Daniel E.
Published: August 2002

This study tests several hypotheses of integration between the cranial base and face in primates. After reviewing the definition and anatomical basis for the posterior maxillary (PM) plane, which demarcates the back of the midface at its junction with the sphenoid, we demonstrate how the PM plane can be identified accurately on radiographs, and confirm that it maintains a 90° angle relative to the Neutral Horizontal Axis of the orbits in all primates. In addition, we use the PM plane to test Dabelow's (1929) hypothesis that the orbits and anterior cranial base are more highly integrated in anthropoids than in strepsirrhines, and we test the hypothesis that the midline anterior cranial base (planum sphenoideum) and anterior cranial floor (planum sphenoideum plus cribriform plate) in primates are highly correlated with each other relative to the PM plane. The mean angle between the anterior cranial base and the PM plane does not differ significantly from 90° in anthropoids, but differs significantly in strepsirrhines. The anterior cranial base and anterior cranial floor, however, correlate well with each other relative to the PM plane in both suborders of primates, independent of orbital orientation and configuration. The PM plane, anterior cranial base, and anterior cranial floor, therefore, form an integrated structural complex, a “facial block,” whose orientation relative to the posterior cranial base influences craniofacial shape among anthropoids in which orbital orientation influences the orientation of the anterior cranial base. One such effect is that increases in cranial base flexion shorten the antero‐posterior length of the nasopharynx. Anat Rec 264:247–260, 2001. © 2001 Wiley‐Liss, Inc.
Cloning and expression of a ferritin subunit forGalleria mellonella
Authors: Kim Beom Su , Yun Chi Young , Yeo Sung Moon , Lee Hye Jeong , Kim Hak R.
Published: August 2002

Ferritin was purified from iron‐fedGalleria mellonellahemolymph by ultra centrifugation and FPLC (Superose 6). SDS‐PAGE revealed three bands of 26, 30, and 32 kDa. The ferritin 26 kDa subunit cDNA was obtained from RT‐PCR using primer designed from N‐terminal sequence analysis. 5′‐RACE was used to obtain the complete protein coding sequence. The sequence encodes a 211 amino acid polypeptide including a 20 amino acid leader peptide. An IRE (iron‐responsive element) sequence with a predicted stem‐loop structure was present in the 5′‐UTR of ferritin mRNA. Sequence alignment has a sequence identity withCalpodes ethlius(S)(74%),Drosophila melanogaster(50%), andAedes aegypti(39%). Northern blot analysis indicated that there were 1.5‐ and 1.75‐fold increases in the expression of ferritin mRNA after iron‐fed fat body and midgut, respectively. Also, we confirmed that the ferritin mRNA is not expressed in adult ovary and testis. Arch. Insect Biochem. Physiol. 47:8–17, 2001. © 2001 Wiley‐Liss, Inc.
The hydroid Hydractinia: a versatile, informative cnidarian representative
Authors: Frank Uri , Leitz Thomas , Müller Werner A.
Published: August 2002

The Cnidaria represent the most ancient eumetazoan phylum. Members of this group possess typical animal cells and tissues such as sensory cells, nerve cells, muscle cells and epithelia. Due to their unique phylogenetic position, cnidarians have traditionally been used as a reference group in various comparative studies. We propose the colonial marine hydroid, Hydractinia, as a convenient, versatile platform for basic and applied research in developmental biology, reproduction, immunology, environmental studies and more. In addition to being a typical cnidarian representative, Hydractinia offers many practical and theoretical advantages: studies that are feasible in Hydra like regeneration, pattern regulation, and cell renewal from stem cells, can be supplemented by genetic analyses and classical embryology in Hydractinia. Metamorphosis of the planula larva of Hydractinia can be used as a model for cell activation and communication and the presence of a genetically controlled allorecognition system makes it a suitable model for comparative immunology. Most importantly, Hydractinia may be manipulated at most aspects of its (short) life cycle. It has already been the subject of many studies in various disciplines, some of which are discussed in this essay. BioEssays 23:963–971, 2001. © 2001 John Wiley & Sons, Inc.
Effect of the geometry of microfabricated flow reactors on chemiluminescent detection of epinephrine with lucigenin
Authors: Kamidate Tamio , Kaide Tomoyuki , Tani Hirofumi , Makino Eiji , Shibata Takayuki
Published: August 2002

Three types of flow reactors with different lengths (12–126 mm) and widths (0.4–2.0 mm) of channel were made on the silicon chip by microfabrication techniques for the chemiluminescent (CL) detection of epinephrine (EP) with lucigenin (Luc). The volume of each CL reactor was about 10 µL. A solution containing EP and Luc and a solution containing NaOH and periodate were injected successively into each inlet of the CL reactor in the range 20–100 µL/min with a pressure‐driven flow system. The intensity of light emission was dependent on the geometry of the flow reactors. These results could be explained in terms of the differences in the diffusion length of the reactants in the flow reactors. The maximum light emission were linearly correlated, with the concentrations of EP over the range from the detection limit of 5.0 × 10−8 mol/L up to 5.0 × 10−6 mol/L on the use of the CL reactor with the most promising geometry. Copyright © 2001 John Wiley & Sons, Ltd.
Noninvasive characterization of human stratum corneum of undiseased skin of patients with atopic dermatitis and psoriasis as studied by Fourier transform Raman spectroscopy
Authors: Wohlrab Johannes , Vollmann Anke , Wartewig Siegfried , Marsch Wolfgang C. , Neubert Reinhard
Published: August 2002

Etiopathogenetic regulatory disorders of epidermal metabolism and the subsequent changes in the molecular pattern of the stratum corneum play an important role in the clinical differentiation of particular dermatoses (e.g., psoriasis, atopic dermatitis). In this study we present in vitro Fourier transform Raman spectra of the stratum corneum from healthy skin, as well as from clinically undiseased skin of the right heel of atopic and psoriatic volunteers. Differences in the averaged spectra were detected, particularly in the spectral ranges of 1112–1142 (lipid band), 1185–1220, and 1394–1429 cm−1. By using the first derivative of the averaged spectra and/or a statistical evaluation of the spectroscopic data it was possible to distinguish the skin types examined. © 2001 John Wiley & Sons, Inc. Biopolymers (Biospectroscopy) 62: 141–146, 2001
Resonance Raman spectroscopic studies in copper reconstituted and hybrid hemoglobins: Probe into subunit heterogeneity
Authors: Swarnalatha V. , Balakrishnan G. , Manoharan P. T.
Published: August 2002

Copper reconstituted hemoglobin (CuHb), copper containing T‐state hybrid hemoglobins like α2(Ni)β2(Cu), and α2(Cu)β2(Ni), and intermediate R‐state hybrids like α2(CO‐Fe)β2(Cu) and α2(Cu)β2(Fe‐CO) are studied using resonance Raman (RR) spectroscopy at two different excitation wavelengths. The high frequency RR region in CuHb indicates the presence of both 4‐ and 5‐coordinate forms of Cu(II). In hybrid Hbs, the presence of two distinct metal ion environments within one particular subunit is evident. This is also consistent with previous findings using EPR spectroscopy and sulfydryl reactivity studies on these hybrid Hbs. The low frequency RR region on these copper derivatives of HbA further suggests the existence of two different heme moieties within the subunit. © 2002 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 67: 156–166, 2002
Mapping nucleotide binding site of calcium ATPase with IR spectroscopy: Effects of ATP γ‐phosphate binding
Authors: Liu Man , Barth Andreas
Published: August 2002

The changes in the IR spectra of the sarcoplasmic reticulum Ca2+‐ATPase upon nucleotide binding are recorded in H2O at 1°C in different buffers [imidazole, methylimidazole, 3‐(N‐morpholino)propanesulfonic acid, and phosphate] at different pH values (pH 6.5–7.8). The difference spectra of nucleotide binding are sensitive to the composition of the solvent. With methylimidazole at pH 7.5 providing the largest binding‐induced signals, the effects of γ‐phosphate binding are investigated using ATP, ADP, and β,γ‐iminoadenosine 5′‐triphosphate. The γ‐phosphate contributes ∼20% to the conformational change seen by IR spectroscopy and affects the β‐sheet structures. The IR experiments also reveal the known affinity difference between ADP and ATP. © 2002 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 67: 267–270, 2002
Structural features of model glycopeptides in solution and in membrane phase: A spectroscopic and molecular mechanics investigation
Authors: Stella L. , Venanzi M. , Carafa M. , Maccaroni E. , Straccamore M. E. , Zanotti G. , Palleschi A. , Pispisa B.
Published: August 2002

Model glycopeptides of the general formula Boc–Ala–Thr(G–D)–A1–A2–Leu–Leu–Lys(N)–Ala–OMe, where D = dansyl (dimethyl aminonaphthalenesulphonyl), G = glucosyl and N = naphthyl, while A1–A2 = Ala–Leu or Aib–Aib, and denoted as D–G–Ala–N and D–G–Aib–N, respectively, were used to investigate glycoprotein–membrane interactions. They carry two fluorophores (D and N), covalently linked to the glucose ring and the lysine side chain, respectively, while the threonine side chain is O‐glycosylated. CD spectra in different solvent media suggest that both glycopeptides attain an ordered structure, possibly a helix‐like conformation. By combining FRET (fluorescence resonance energy transfer) experiments with molecular mechanics data, the most probable structures of both glycopeptides were built up, starting from both a right‐handed (rh) α‐ and 310‐helix. They were found to populate an α‐helical conformation, a result further confirmed by the very good agreement between theoretical and experimental quenching efficiency only observed when the backbone chain was in α‐helix. The association of D–G–Ala–N with model membranes (liposomes) was studied by CD, fluorescence decay, fluorescence anisotropy, and collisional quenching experiments. The binding does not alter the structural features of the peptide because the CD spectral patterns are unaffected by the association. The peptide orientation inside the phospholipidic bilayer is guided by the polar glucose molecule lying in the water phase. The insertion of the hydrophobic backbone chain into the membrane, seeing the probes only partially accessible from the external solution, is characterized by a significant degree of heterogeneity, an increase in vesicles size, and a relevant stabilizing effect on the membrane itself against rupture by methanol. © 2002 Wiley Periodicals, Inc. Biopolymers 64: 44–56, 2002
Decolorization of reactive dyes by the white rot fungus Trametes versicolor in sequencing batch reactors
Authors: Borchert Maren , Libra Judy A.
Published: August 2002

The white rot fungus Trametes versicolor was shown to be capable of decolorizing three reactive dyes in a sequencing batch process, using glucose as the carbon and energy source over an extended period without supplementation of new mycelium. Decolorization activity was related to the expression of extracellular peroxidases and could be continuously reactivated by sheering the suspended pellets. Pure culture experiments were carried out simultaneously in agitated Erlenmeyer flasks and in completely stirred tank reactors with two azo dyes, C.I. Reactive Black 5 and C.I. Reactive Red 198 as well as the anthraquinone dye C.I. Reactive Blue 19 (Brilliant Blue R). Results show high and stable degrees of decolorization of 91%–99% in both systems, which could be repeated without decrease in activity over time. Under nonsterile conditions only five cycles of decolorization could be achieved. An increasing bacterial population suppressed fungal growth and the formation of peroxidases. © John Wiley & Sons, Inc. Biotechnol Bioeng 75: 313–321, 2001.
Scaleable downstream recovery of nematodes used as biopesticides
Authors: Wilson J.A. , Pearce J.D. , Shamlou P. Ayazi
Published: August 2002

This study assesses the suitability of sieving as a scaleable technique for the separation of adult nematodes from infective juveniles, the latter is an effective bioinsecticide whereas the former is waste material resulting from the fermentation process. Batch and semibatch experiments using conventional flow‐assisted wet sieving and a novel cross‐flow sieving technique were used to study the separation of juveniles from adult nematodes. The experiments were carried out using small‐scale devices and the data were analyzed in terms of the screen effectiveness factor. The results were used to identify the sieve size and operating conditions for optimum juvenile recovery. It was found that, for a given species of nematode, optimum recovery was achieved when sieving was carried out in the cross‐flow mode, the maximum recovery being a function of the size of the screen. Industrial‐scale self‐cleaning equipment capable of large‐scale continuous screening was used to confirm the capacity of the small‐scale operation for scale‐up. Experimental results with this unit showed that in continuous operation sieving time is an additional parameter that influences separation performance. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 733–740, 2001.
Stabilization of α‐chymotrypsin by ionic liquids in transesterification reactions
Authors: Lozano Pedro , de Diego Teresa , Guegan Jean‐Paul , Vaultier Michel , Iborra José L.
Published: August 2002

Five different ionic liquids, based on dialkylimidazolium and quaternary ammonium cations associated with perfluorinated and bis (trifluoromethyl) sulfonyl amide anions, were used as reaction media to synthesize N‐acetyl‐L‐tyrosine propyl ester by transesterification with α‐chymotrypsin at 2% (v/v) water content at 50°C. The synthetic activity was reduced by the increase in alkyl chains length of cations and by increases in anion size, which was related to the decrease in polarity. Incubation of the enzyme (with and without substrate) in ionic liquids exhibited first‐order deactivation kinetics at 50°C, allowing determination of deactivation rate constants and half‐life times (1–3 h). Ionic liquids showed a clear relative stabilization effect on the enzyme, which was improved by increased chain length of the alkyl substituents on the imidazolium ring cations and the anion size. This effect was 10‐times enhanced by the presence of substrate. For example, 1‐butyl‐3‐methylimidazolium hexafluorophosphate increased the α‐chymotrypsin half‐life by 200 times in the presence of substrate with respect to the 1‐propanol medium. These results show that ionic liquids are excellent enzyme‐stabilizing agents and reaction media for clean biocatalysis in non‐conventional conditions. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 563–569, 2001.
A morphologically structured model for penicillin production
Authors: Birol Gülnur , Ündey Cenk , Parulekar Satish J. , Çınar Ali
Published: August 2002

A morphologically structured model is proposed to describe penicillin production in fed‐batch cultivations. The model accounts for the effects of dissolved oxygen on cell growth and penicillin production and variations in volume fractions of abiotic and biotic phases due to biomass formation. Penicillin production is considered to occur in the subapical hyphal cell compartment and to be affected by availability of glucose and oxygen. As it stands, the model provides a wide range of applicability in terms of operating conditions. The model has been tested for various conditions and has given satisfactory results. A series of glucose feeding profiles have been considered to demonstrate the capabilities of the proposed model. It is concluded that the model may be valuable for the interpretation of experimental data collected specifically for metabolic flux analysis during fed‐batch cultivation because the elements of measured specific production rates are determined from measurements of the concentrations of the components and their mass balances. The proposed model may be further used for developing control strategies and model order reduction algorithms. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 538–552, 2002; DOI 10.1002/bit.10115
Continuous pH monitoring in a perfused bioreactor system using an optical pH sensor
Authors: Jeevarajan Antony S. , Vani Sundeep , Taylor Thomas D. , Anderson Melody M.
Published: August 2002

Monitoring and regulating the pH of the solution in a bioprocess is one of the key steps in the success of bioreactor operation. An in‐line optical pH sensor, based on the optical absorption properties of phenol red present in the medium, was developed and tested in this work for use in NASA space bioreactors based on a rotating wall‐perfused vessel system supporting a baby hamster kidney (BHK‐21) cell culture. The sensor was tested over three 30‐day and one 124‐day cell runs. The pH sensor initially was calibrated and then used during the entire cell culture interval. The pH reported by the sensor was compared to that measured by a fiber optically coupled Shimadzu spectrophotometer and a blood gas analyzer. The maximum standard error of prediction for all the four cell runs for development pH sensor against BGA was ±0.06 pH unit and for the fiber optically coupled Shimadzu spectrophotometer against the blood gas analyzer was ±0.05 pH unit. The pH sensor system performed well without need of recalibration for 124 days. © 2002 Wiley Periodicals, Inc.* Biotechnol Bioeng 78: 467–472, 2002.
How psychiatrists and judges assess the dangerousness of persons with mental illness: an ‘expertise bias’
Authors: Poletiek Fenna H.
Published: August 2002

When assessing dangerousness of mentally ill persons with the objective of making a decision on civil commitment, medical and legal experts use information typically belonging to their professional frame of reference. This is investigated in two studies of the commitment decision. It is hypothesized that an ‘expertise bias’ may explain differences between the medical and the legal expert indefiningthe dangerousness concept (study 1), and in assessing theseriousnessof the danger (study 2). Judges define dangerousness more often as harming others, whereas psychiatrists more often include harm to self in the definition. In assessing the seriousness of the danger, experts tend to be more tolerant with regard to false negatives, as the type of behavior is more familiar to them. The theoretical and practical implications of the results are discussed. Copyright © 2002 John Wiley & Sons, Ltd.
What do we really know about witness preparation?
Authors: Boccaccini Marcus T.
Published: August 2002

Witnesses often meet with an attorney or witness preparation specialist before trial to review, discuss, and sometimes modify the substance and delivery of their anticipated testimony. This process is commonly referred to as witness preparation. During witness preparation, witnesses are taught to use effective testimony delivery skills (e.g., verbal and nonverbal communication skills) so that they will be perceived as being credible and persuasive in the courtroom. Although social scientists know much about communication skills, credibility, and persuasion, few published studies have attempted to determine whether or not these factors can be modified through witness preparation training. The present article reviews the psychological literature pertaining to witness preparation and makes recommendations for needed witness preparation research. Copyright © 2002 John Wiley & Sons, Ltd.
Equality in hiring permanent resident foreign nationals in the United States: when loyalty is the question, but not the issue
Authors: Wiersma Uco Jay
Published: August 2002

Permanent resident foreign nationals, who have been legally admitted to the United States, have the right to work. However, when deciding the constitutionality of a state statute that requires citizenship for a public domain job, the rights of permanent residents to seek gainful employment are balanced against the rights of state governments to ensure that important sovereign functions are entrusted only to their citizens. Several important Supreme Court decisions have been 5/4 split decisions because of this tension and dissenting judges have countered that the majority rulings were based on presumptions, and not facts, that citizens are more loyal than permanent residents. The judges have also disagreed about the level, within a civil service hierarchy, below which a citizenship requirement is unconstitutional. This article reviews United States court decisions for relevant issues and solutions, and shows how empirical studies in the area of human resource management can help resolve the issues that have caused the dissent. The analysis will be useful to legal and human resource professionals in the U.S. and other countries affected by surging global migration. Copyright © 2002 John Wiley & Sons, Ltd.
Anatomical evidence for the absence of a morphologically distinct cranial root of the accessory nerve in man
Authors: Lachman Nirusha , Acland Robert D. , Rosse Cornelius
Published: August 2002

The accessory nerve is conventionally described as having a cranial and spinal root. According to standard descriptions the cranial root (or part) is formed by rootlets that emerge from the medulla between the olive and the inferior cerebellar peduncle. These rootlets are considered to join the spinal root, travel with it briefly, then separate within the jugular foramen to become part of the vagus nerve. In 15 fresh specimens we exposed the posterior cranial fossa with a coronal cut through the foramen magnum and explored the course of each posterior medullary rootlet (PMR) arising from within the retro‐olivary groove. We chose the caudal end of the olive as the landmark for the caudal end of the medulla. In all specimens every PMR that did not contribute to the glossopharyngeal nerve joined the vagus nerve at the jugular foramen. The distance between the caudal limit of the olive and the origin of the most caudal PMR that contributed to the vagus nerve ranged from 1–21 mm (mean = 8.8 mm). All rootlets that joined the accessory nerve arose caudal to the olive. The distance from the caudal limit of the olive and the most rostral accessory rootlet ranged from 1–15 mm (mean = 5.4 mm). We were unable to demonstrate any connection between the accessory and vagus nerves within the jugular foramen. Our findings indicate that the accessory nerve has no cranial root; it consists only of the structure hitherto referred to as its spinal root. Clin. Anat. 15:4–10, 2002. © 2002 Wiley‐Liss, Inc.
Chemopreventive efficacy of selenium against N‐nitrosodiethylamine‐induced hepatoma in albino rats
Authors: Thirunavukkarasu C. , Prince Vijeya Singh J. , Selvendiran K. , Sakthisekaran D.
Published: August 2002

The chemopreventive/chemotherapeutic effect of sodium selenite on tricarboxylic acid cycle key enzymes was investigated against hepatoma induced by environmental carcinogen N‐nitrosodiethylamine. Decreased activities of TCA cycle key enzymes such as isocitrate dehydrogenase (ICDH), succinate dehydrogenase (SDH), malate dehydrogenase (MDH) and α‐ketoglutarate dehydrogenase (α‐KGDH) in hepatoma and surrounding tissues of hepatoma‐bearing rats were observed. Upon selenium supplementation the above biochemical changes were reverted in a dose‐ and duration‐dependent manner. This study further confirms the chemopreventive/chemotherapeutic effect of sodium selenite which is found to be more effective in the initiation phase of carcinogenesis. Copyright © 2001 John Wiley & Sons, Ltd.
Dual Enrollment for Underrepresented Student Populations
Authors: Hugo Esther B.
Published: August 2002

The dual enrollment program at Santa Monica College facilitates the school‐to‐college transition and improves access to college for diverse populations. Traditionally underrepresented students, whose college options have suffered in light of a hostile political climate evidenced by the Hopwood decision, Proposition 209, and Proposition 187, may gain access to college curricula and develop a positive academic self‐image based on successful participation in a dual enrollment program.
Stenting for coronary artery spasm
Authors: Khatri Shailesh , Webb John G. , Carere Ronald G. , Dodek Arthur
Published: August 2002

We evaluated coronary stenting in nine patients with clinically severe, angiographically documented spasm refractory to aggressive pharmacologic management. No patient subsequently developed unstable ischemia requiring hospitalization as a consequence of recurrent spasm within the stent. Mechanisms of therapeutic failure included both peristent spasm and spasm in a different artery in one patient. Restenosis occurred in three patients who subsequently underwent repeat revascularization. In the rare, carefully selected patient, stents may represent an adjunct in the management of focal coronary artery spasm, although currently medical therapy remains the standard initial approach. Cathet Cardiovasc Intervent 2002;56:16–20. © 2002 Wiley‐Liss, Inc.
Transradial renal angioplasty: Initial experience
Authors: Shuck John , Khan Amid , Cavros Nick , Galanakis Stylianos , Patel Vishal
Published: August 2002

We report our early experience of a new technique of renal angioplasty utilizing the radial approach. Certain anatomic considerations continue to make access from above via the arm the preferable approach in selected patients in renal artery stenosis. We have utilized the transradial technique for renal artery angioplasty and stenting successfully in four patients. The development of coronary guidewire (0.014″)‐based peripheral balloons and stent delivery systems has miniaturized equipment sufficiently to make the transradial approach attractive. Present equipment allows for stenting of renal arteries of up to 7 mm with the use of 6 Fr guiding catheters. Present equipment length remains a limitation in taller patients. The transradial approach should be considered in those patients with renal artery or aortoiliac anatomy favoring an approach from the arm. Cathet Cardiovasc Intervent 2001;54:346–349. © 2001 Wiley‐Liss, Inc.