bluuebunny/crossref_metadata_2025 huggingface dataset:
Nerve growth factor and acetyl‐L‐carnitine evoked shifts in acetyl‐CoA and cholinergic SN56 cell vulnerability to neurotoxic inputs
Authors: Szutowicz Andrzej , Bielarczyk Hanna , Gul Sylwia , Zieliński Piotr , Pawełczyk Tadeusz , Tomaszewicz Maria
Published: November 2004

Different groups of brain cholinergic neurons display variable susceptibility to similar neurotoxic inputs. The aim of this work was to find out whether changes in cholinergic phenotype may alter the availability of acetyl‐CoA in mitochondrial compartment and thereby the viability of cholinergic neurons. Cyclic AMP (cAMP) and retinoic acid caused differentiation (DC) of T17 TrkA(+) cholinergic neuroblastoma cells. In addition, it increased the choline acetyltransferase (ChAT) activity, Ca2+ accumulation and cytoplasmic acetyl‐CoA level, but decreased mitochondrial acetyl‐CoA and cell resistance to amyloid‐β(25–35) (Aβ) toxicity. Nerve growth factor (NGF) caused similar alterations in the nondifferentiated cells (NC). On the other hand, in DC NGF suppressed ChAT activity and elevated mitochondrial level of acetyl‐CoA but also caused a further increase of Ca2+ content and cell susceptibility to Aβ. The significant inverse correlation was found between ChAT activity and mitochondrial levels of acetyl‐CoA. Aβ markedly reduced the expression of cholinergic phenotype, acetyl‐CoA content, and viability of DC. These effects were absent or much less pronounced in NC. Acetyl‐L‐carnitine reversed suppressing effects of Aβ on acetyl‐CoA levels and ChAT activity but did not reverse increased mortality in DC. Presented data indicate that increased transmitter activity in highly differentiated cholinergic neurons, decreased acetyl‐CoA level in their mitochondrial compartment, and increased Ca2+ accumulation can make them more prone to neurotoxic conditions. Phenotype‐dependent changes in intracellular distribution of acetyl‐CoA thus play an important role in regulation of viability and transmitter function in brain cholinergic neurons. © 2004 Wiley‐Liss, Inc.
Ex vivo NMR study of lactate metabolism in rat brain under various depressed states
Authors: Serres Sébastien , Bezancon Eric , Franconi Jean‐Michel , Merle Michel
Published: November 2004

Brain endogenous lactate metabolism was investigated by ex vivo nuclear magnetic resonance (NMR) spectroscopy study after the infusion of rats with a solution of glucose and lactate labeled as either [3‐13C]lactate or [1‐13C]glucose, when their cerebral activity was more or less depressed under the influence of either pentobarbital, αchloralose, or morphine. We found that: (1) the ratio between the enrichment of alanine C3 and that of glutamate C4, γ‐aminobutyric acid (GABA) C2, glutamine C4, or aspartate C3 decreased from pentobarbital to αchloralose and morphine whatever the labeled precursor, indicating a link between metabolic and cerebral activity; (2) under glucose + [3‐13C]lactate infusion, alanine C3 and acetyl‐CoA C2 enrichments were higher than that of lactate C3, revealing the occurrence of an isotopic dilution of the brain exogenous lactate (arising from the blood) by lactate from the brain (endogenous lactate), and that the latter was synthesized from glycolysis in a compartment other than neurons; and (3) the contribution of labeled glucose and lactate to acetyl‐CoA and amino acid enrichment indicated that the involvement of blood glucose relative to that of blood lactate to brain metabolism was correlated with cerebral activity. The evolution of metabolite enrichments, however, indicated that the cerebral activity‐dependent increase in the contribution of blood glucose relative to that of blood lactate to brain metabolism occurred partly via the increase in lactate metabolism generated from astrocytic glycolysis. These findings support the hypothesis for an astrocyte–neuron lactate shuttle component in the coupling mechanism between cerebral activity and energy metabolism. © 2004 Wiley‐Liss, Inc.
Nitric oxide from inflammatory‐activated glia synergizes with hypoxia to induce neuronal death
Authors: Mander Palwinder , Borutaite Vilma , Moncada Salvador , Brown Guy C.
Published: November 2004

Inflammatory‐activated glia are seen in numerous central nervous system (CNS) pathologies and can kill nearby neurons through the release of cytotoxic mediators. Glia, when activated, can express the inducible isoform of nitric oxide synthase (iNOS) producing high levels of nitric oxide (NO), which can kill neurons in certain conditions. We show, however, that inflammatory activation of glia in a mature culture of cerebellar granule neurons and glia causes little or no neuronal death under normal (21%) oxygen conditions. Similarly, hypoxia (2% oxygen) or low levels of an NO donor (100 μM DETA/NO) caused little or no neuronal death in nonactivated cultures. If inflammatory activation of glia or addition of NO donor was combined with hypoxia, however, extensive neuronal death occurred. Death in both cases was prevented by the N‐methyl‐D‐aspartate (NMDA) receptor blocker MK‐801, implying that death was mediated by the glutamate receptor. Low levels of NO were found to increase the apparent KM of cellular oxygen consumption for oxygen, probably due to NO‐induced inhibition of mitochondrial respiration, in competition with oxygen, at cytochrome oxidase. Necrotic death, induced by hypoxia plus DETA/NO, was increased further by deoxyglucose, an inhibitor of glycolysis, suggesting that necrosis was mediated by energy depletion. Hypoxia was found to be a potent stimulator of microglia proliferation, but this proliferation was not significant in inflammatory‐activated cultures. These results suggest that low levels of NO can induce neuronal death under hypoxic conditions, mediated by glutamate after NO inhibition of respiration in competition with oxygen. Brain inflammation can thus sensitize to hypoxia‐induced death, which may be important in pathologies such as stroke, neurodegeneration, and brain aging. © 2004 Wiley‐Liss, Inc.
Diversity and abundance of Bacteria and Archaea in the Bor Khlueng Hot Spring in Thailand
Authors: Kanokratana Pattanop , Chanapan Supavadee , Pootanakit Kusol , Eurwilaichitr Lily
Published: November 2004

The prokaryotic diversity in the Bor Khlueng hot spring in Ratchaburi province, Thailand was investigated by a culture‐independent molecular approach. This hydrothermal pool is located in the central part of Thailand and contains sulfide‐rich mineral water that is believed to relieve muscle ache and pain. The water flow year‐round with temperature ranging between 50–57 °C. Community DNA was extracted directly from sediment samples by coring to depth of ∼20–30 cm. Small‐subunit rRNA genes (16S rDNA) were amplified by PCR using primers specific for the domains Archaea and Bacteria. The PCR products were cloned and sequenced. For the bacterial rDNA clone library, 200 clones were randomly selected for further analyses. After restriction fragment length polymorphism (RFLP) analysis of rDNA clones and exclusion of chimeric sequences 36 phylotypes were obtained. The Bor Khlueng phylotypes spanned a wide range within the domain Bacteria, occupying eleven major lineages (phyla). Almost a quarter (23%) of the clones were classifed as Acidobacteria. The other clones were grouped into the Bacteriodetes (19%), Nitrospirae (13%), Proteobacteria (12%), Deinococcus‐Thermus lineage (11%), planctomycetes (6%), and Verrucomicrobia (5%). The four remaining phyla, 5% each, were assigned to Actinobacteria, Chloroflexi, Cyanobacteria, and the candidate division “OP10”. For the archaeal 16S rRNA gene sequence library, 25 distinct phylotypes were obtained, 17 clones were found to be associated with Crenarahaeota and 8 clones were associated with Euryarachaeota. The findings of the molecular survey of this so far not investigated site showed that Bor Khlueng hot spring is a potential rich source of unique bacterial and archaeal species. The great majority (∼80%) of the prokaryotic sequences detected in Bor Khlueng were unknown. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparison of Botryosphaeran production by the ascomyceteous fungus Botryosphaeria sp., grown on different carbohydrate carbon sources, and their partial structural features
Authors: Steluti Rosangela M. , Giese Ellen C. , Piggato Mariane M. , Sumiya Andressa F. G. , Covizzi Luiz G. , Job Aldo E. , Cardoso Marilsa S. , De Lourdes Corradi Da Silva Maria , Dekker Robert F. H. , Barbosa Aneli M.
Published: November 2004

The influence of glucose concentration and other carbohydrates (monosaccharides: fructose, galactose, mannose; polyols: mannitol and sorbitol; disaccharides: lactose, sucrose and commercial sucrose; and industrial sugarcane molasses) were compared as sole carbon sources for the production of Botryosphaeran, an exopolysaccharide (EPS) produced by Botryosphaeria sp. The optimum glucose concentration for EPS production was 50 g l–1. With the exception of mannitol, the fungus produced EPS on all carbon sources studied, with highest yields occurring with sucrose followed by glucose. All EPS showed exclusively glucose after acid hydrolysis and monosaccharide analysis. FTIR spectroscopy demonstrated the presence of β‐anomers indicating that all the EPS produced by Botryosphaeria sp. on the different carbon sources were essentially of the β‐D‐glucan type. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Selection of cultivation medium for production of late stationary phase serine proteinases from Bacillus intermedius
Authors: Balaban Nelly , Gabdrakhmanova Leila , Sharipova Margarita , Sokolova Evgeniya , Malikova Lilia , Mardanova Ayslu , Rudenskaya Galina , Leshchinskaya Inna
Published: November 2004

B. intermedius have been shown previously to secrete two serine proteinases: glutamyl endopeptidase 2 and subtilisin 2 during the late stationary phase, with maximal levels of the enzymes activities recorded at the 40th and 44th hours of growth, respectively. In the current study, we analyzed the impact of various culture medium components on biosynthesis of these proteinases. Yeast extract and gelatin did not stimulate the enzymes biosynthesis. However, on the medium containing 0.1% casein subtilisin 2 production increased to reach 140%. Biosynthesis of both serine proteinases, produced by B. intermedius at the late stationary phase, were found to be inhibited by individual amino acids, and to be insensitive to catabolite repression. In order to maximise enzyme production, the presence of Ca2+ and Mg2+ at concentration of 5 mM was shown to be necessary. Based on the results of this work, the composition of a complex culture media for the effective production of late stationary phase proteinases by B. intermedius was developed. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Indirect identification of isoprenoid quinones in Escherichia coli by LC‐MS with atmospheric pressure chemical ionization in negative mode
Authors: Gao Mengchun , Liu HongJun , Yang Min , Hu JianYing , Shao Bing
Published: November 2004

A novel analytical method was applied for identification of isoprenoid quinones in Escherichia coli by liquid chromatography atmospheric press chemical ionization mass spectrometry in negative mode (LC‐NI‐APCI‐MS). Extraction and clean‐up of sample were carried out on Sep‐Pak Plus Silica solid‐phase extraction cartridges. Ubiquinone‐7 (UQ‐7), Ubiquinone‐8 (UQ‐8) and Mequinone‐8 (MK‐8) were determined directly using combined information on retention time, molecular ion mass, fragment ion masses and UV characteristic spectrometry without any standard reagent. It was found that UQ‐8 was the major component of isoprenoid quinones in Escherichia coli under aerobic condition. Compared with UQ‐8, the relative abundance of UQ‐7 and MK‐8 is only 15% and 14%, respectively. The average recoveries of UQ‐6, UQ‐10 and vitamin K1 in Escherichia coli were investigated by standard spiking experiment. The recoveries were achieved in the range from 94 to 106%, and the relative standard deviations (RSD) of the triplicate analysis of the spiked samples (UQ‐6, UQ‐10 and vitamin K1) ranged from 3 to 8%. The detection limits of LC‐NI‐APCI‐MS were estimated to be 5, 40 and 0.8 μg/g dry cell for UQ‐6, UQ‐10 and vitamin K1, respectively. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Bacillus megaterium comE locus encodes a functional DNA uptake protein
Authors: Lammers Michael , Nahrstedt Hannes , Meinhardt Friedhelm
Published: November 2004

From Bacillus megaterium, a genomic region was isolated and structurally characterized which strongly resembles the Bacillus subtilis competence locus comE encoding proteins involved in DNA uptake. Functionality of the B. megaterium comEA gene was proven by complementing a DNA‐receptor mutant of B. subtilis. This finding provides first evidence for a latent ability of B. megaterium to develop natural competence, although such physiological state has not as yet been identified in this organism. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Number-of-particle fluctuations in systems with Bose-Einstein
condensate
Authors: Yukalov V I
Published: November 2004

Fluctuations of the number of particles for the dilute
interacting gas with Bose-Einstein condensate are considered. It
is shown that in the Bogolubov theory these fluctuations are
normal. The fluctuations of condensed as well as noncondensed
particles are also normal both in canonical and grand canonical
ensembles.
On the theory of matter wave amplification in a Bose–Einstein condensate of dilute gas
Authors: Trifonov E D
Published: November 2004

The solution of the Maxwell-Schrodinger equations describing amplification of backwards matter waves the in process of light scattering from a Bose-Einstein condensate of dilute gas is presented. The results obtained in the mean field approximation explain the main features of the effects observed in [1].
Characterization of a Poly(2‐oxazoline) Library by High‐Throughput, Automated Contact‐Angle Measurements and Surface‐Energy Calculations
Authors: Wijnans Sanne , de Gans Berend‐Jan , Wiesbrock Frank , Hoogenboom Richard , Schubert Ulrich S.
Published: November 2004

Summary: The feasibility of automated, high‐throughput contact‐angle measurements is demonstrated using a modified commercial contact‐angle measuring apparatus. Droplets are automatically dispensed, analyzed and aspirated. The system automatically measures more than 100 contact angles per hour using two test liquids, and calculates surface energies using the equation of state method. A library of poly(2‐oxazoline) homo‐ and block copolymers was investigated. Polymers with a 2‐nonyl‐2‐oxazoline block were found to have considerably lower surface energies.

Setup used here for characterization of the surface properties of a library of poly(2‐oxazoline) homo‐ and block copolymers.

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Setup used here for characterization of the surface properties of a library of poly(2‐oxazoline) homo‐ and block copolymers.
Towards the Nature of Active Sites in Polymerization of Cyclic Esters Initiated by Aluminium Alkoxides: First Structurally Authenticated Aluminium‐ε‐Caprolactone Complex
Authors: Lewiński Janusz , Horeglad Paweł , Tratkiewicz Ewa , Grzenda Wojciech , Lipkowski Janusz , Kolodziejczyk Edyta
Published: November 2004

Summary: The isolation and structural characterization of a methylaluminium(bisphenoxide)‐ε‐caprolactone complex is reported. While the three‐coordinate methylaluminium complex was found not to catalyze the polymerization of ε‐caprolactone, its oxygenation led to the formation of an aluminium methoxide compound, which appeared to be a very good initiator. The relative propensity of the AlX bonds for monomer insertion in the initial step of polymerization is also discussed.

Structure of the methylaluminium(bisphenoxide)‐ε‐caprolactone complex reported here.

image

Structure of the methylaluminium(bisphenoxide)‐ε‐caprolactone complex reported here.
Asymptotics of solutions for sub critical non‐convective type equations
Authors: Hayashi Nakao , Kaikina Elena I. , Naumkin Pavel I.
Published: November 2004

We study the Cauchy problem for non‐linear dissipative evolution equationsequation imagewhere ℒ︁ is the linear pseudodifferential operatorand the non‐linearity is a quadratic pseudodifferential operatorequation imageû≡ ℱx→ξuis the Fourier transformation. We consider non‐convective type non‐linearity, that is we suppose thata(t,0,y) ≠ 0. Let the initial data$u_{0} \in {\bf H}^{\varrho,0} \cap {\bf H}^{0, \varrho}, \varrho > {1\over 2}$, are sufficiently small and have a non‐zero total mass$\int u_{0}(x){\rm d}x \ne 0$, whereis the weighted Sobolev space. Then we give the main term of the large time asymptotics of solutions in the sub critical case. Copyright © 2004 John Wiley & Sons, Ltd.
Second‐order analysis and design of steel structures allowing for member and frame imperfections
Authors: Gu J. X. , Chan S. L.
Published: November 2004

Conventional linear analysis is deficient in handling the design of slender frames since the effective length and other non‐linear effects are difficult to assess accurately. Some proposed non‐linear analyses cannot be directly employed for practical design since they are unable to re‐produce the buckling curves of the basic structural element, a simple column under axial force, by a single element per member. This paper describes an advanced element, using the same physical significance as the advanced and second‐order analysis proposed by a number of researchers and the BS5950(2000) and AS4100 (1995), for practical design of slender steel frames. The proposed element captures the physical behaviour of a structural member that the buckling strength of the member can be predicted using a single element per member and without assuming any effective length. Copyright © 2004 John Wiley & Sons, Ltd.
Dynamic response and reliability analysis of structures with uncertain parameters
Authors: Li Jie , Chen Jian‐Bing
Published: November 2004

An original approach for dynamic response and reliability analysis of stochastic structures is proposed. The probability density evolution equation is established which implies that incremental rate of the probability density function is related to the structural response velocity. Therefore, the response analysis of stochastic structures becomes an initial‐value partial differential equation problem. For the dynamic reliability problem, the solution can be derived through solving the probability density evolution equation with an initial value condition and an absorbing boundary condition corresponding to specified failure criterion. The numerical algorithm for the proposed method is suggested by combining the precise time integration method and the finite difference method with TVD scheme. To verify and validate the proposed method, a SDOF system and an 8‐storey frame with random parameters are investigated in detail. In the SDOF system, the response obtained by the proposed method is compared with the counterparts by the exact solution. The responses and the reliabilities of a frame with random stiffness, subject to deterministic excitation or random excitation, are evaluated by the proposed method as well. The mean, the standard deviation and the reliabilities are compared, respectively, with the Monte Carlo simulation. The numerical examples verify that the proposed method is of high accuracy and efficiency. Moreover, it is found that the probability transition of structural responses is like water flowing in a river with many whirlpools, showing complexity of probability transition process of the stochastic dynamic responses. Copyright © 2004 John Wiley & Sons, Ltd.
Safety of anthrax vaccine: an expanded review and evaluation of adverse events reported to the Vaccine Adverse Event Reporting System (VAERS)
Authors: Sever John L. , Brenner Alan I. , Gale Arnold D. , Lyle Jerry M. , Moulton Lawrence H. , Ward Brian J. , West David J.
Published: November 2004

Purpose

To assess the safety of a licensed anthrax vaccine (AVA) given to more than 500 000 US military personnel, through review and medical evaluation of adverse events (AEs) reported to the Vaccine Adverse Event Reporting System (VAERS).

Methods

AEs were summarized by person, vaccine lot, type, frequency and impact. A Delphic approach was used to tentatively assess causality in an effort to detect serious AEs (SAEs) or other medically important AEs (OMIAEs) possibly attributable to AVA.

Results

The Anthrax Vaccine Expert Committee (AVEC) reviewed 1841 reports describing 3991 AEs (9.4 reports/10 000 doses of AVA) that were submitted to VAERS from 1Q1998 through 4Q2001. One hundred forty‐seven reports described an SAE or OMIAE, of which 26 were tentatively rated as possible, probable or certain consequences of vaccination (injection‐site reaction [12], ‘anaphylactic‐like reaction’ [5] and eight other systemic AEs [1–2 each]).

Conclusions

This review produced no evidence for an unusual rate of any SAE or OMIAE attributable to AVA. It supported an earlier impression that AVA may cause significant local inflammation and should be administered over the deltoid rather than the triceps to avoid direct or compression injury to the ulnar nerve. The subjects of VAERS reports tended to be older than all recipients of AVA. Females generally had and/or reported AEs more often than males, but transient articular reactions were surprisingly more common in males. Variations in the frequency or severity (as judged by hospitalization and/or loss of duty) of reported AEs did not suggest a significant problem with (1) a particular lot of AVA, (2) recurrent AEs after multiple doses or (3) vaccination of persons with a concomitant illness or those given other vaccines or medications. Copyright © 2004 John Wiley & Sons, Ltd.
Predictors of receipt of a fluoroquinolone versus trimethoprim‐sulfamethoxazole for treatment of acute pyelonephritis in women in Manitoba, Canada
Authors: Carrie Anita G. , Metge Colleen J. , Collins David M. , Harding Godfrey K. M. , Zhanel George G.
Published: November 2004

Purpose

The increasing and comparatively high proportion of uropathogens in Canada resistant to trimethoprim‐sulfamethoxazole (TMP‐SMX) may be partially responsible for the increasing use of fluoroquinolones. A number of patient‐specific variables have been identified as risk factors for infections caused by antibiotic‐resistant pathogens. However, variables unrelated to need, have also been associated with receipt of broad‐spectrum antibiotics. We identified patient variables associated with receipt of a fluoroquinolone versus TMP‐SMX for treatment of acute pyelonephritis.

Methods

Healthcare claims from the province of Manitoba, Canada for the period February 1996 to March 1999 were examined to identify episodes of pyelonephritis in non‐pregnant females between 18 and 65 years of age treated with TMP‐SMX or a fluoroquinolone. Patient variables were identified based on healthcare claims review and data from Statistics Canada. Logistic regression was used to model the probability of receipt of a fluoroquinolone.

Results

A total of 1084 women met inclusion criteria; 653 treated with TMP‐SMX and 431 treated with a fluoroquinolone. Age, income, rural residence, recent antibiotic use, recent hospitalization and presentation to an emergency room (ER) were positively associated with receipt of a fluoroquinolone.

Conclusions

Patient variables reportedly associated with an increased probability of resistant organisms (e.g., age, recent antibiotic use and recent hospitalization) were significantly associated with an increased probability of receipt of fluoroquinolones. However, variables unrelated to antibiotic resistance (e.g., income, rural residence and presentation to an ER) were also significantly associated with receipt of a fluoroquinolone. Copyright © 2004 John Wiley & Sons, Ltd.
Factors affecting the adsorption of cationic dyes on polymeric hydrogels prepared by gamma irradiation
Authors: Ismail Laila FM , Maziad Nabila A , Abo‐Farha Samia A
Published: November 2004

The adsorption of the cationic dyes Rhodamine B (RB) and Crystal Violet (CV) on polyacrylamide/poly(acrylic acid) (poly(AAm/AAc), 25:25 % weightwise) and polyacrylamide/poly(sodium acrylate) (poly(AAm/AAcNa), 25:25 % weightwise) hydrogels was studied, employing the Langmuir and Freundlich isotherms. The results of swelling tests at pH 5.5 indicate that poly(AAm/AAcNa) hydrogel shows maximum percentage swelling (%S) was 4400 %. Moreover, the results show that the adsorption capacity is pH‐ and concentration‐dependent. At pH >5 adsorption of RB and CV increases due to ionization of COOH and COONa groups of (poly(AAm/AAc) and (poly(AAm/AAcNa) and interactions with the cationic groups of the dyes. However, at pH lower than 5, adsorption is still high, which can be explained by considering the formation of hydrogen bonds between the amino groups of the dyes and the COOH groups of the polymeric hydrogels. Moreover, the kinetics of adsorption follows a first‐order equation. Furthermore, scanning electron microscopy (SEM) micrographs of polymeric hydrogels doped with CV and RB have morphological differences from the pure form. Our data show that Rhodamine B adsorbs more efficiently on both polyacrylamide/poly(acrylic acid) and polyacrylamide/poly(sodium acrylate) hydrogels than CV. Copyright © 2004 Society of Chemical Industry
Poly(ether ketone)–polyisobutylene block copolymers: Synthesis and phase behavior
Authors: Binder Wolfgang H. , Machl Doris
Published: November 2004

Telechelic poly(ether ketone)s (PEKs) and polyisobutylenes (PIBs) were combined to form PIBPEKPIB triblock copolymers and (PIBPEK)n multiblock copolymers via the formation of urea linkages. Monovalent and bivalent amino telechelic PIBs were prepared quantitatively from allyl telechelic PIBs by a newly developed reaction sequence featuring nucleophilic reaction steps. Telechelic PEKNCO polymers were prepared from the corresponding amino telechelic PEKs via a reaction with diphosgene. The highly reactive PEKNCO and PIBNH2 telechelics formed PEKPIB block copolymers only quantitatively when appropriately reactive primary amino groups were present on the amino telechelic PIBs. The obtained block copolymers were microphase‐separated and featured mostly lamellar structures, as determined by small‐angle X‐ray scattering (SAXS). Temperature‐dependent SAXS measurements revealed ordered polymers in the melt up to 210 °C. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 188–202, 2005
Synthesis, characterization, thermal properties, and antimicrobial activity of 4‐chloro‐3‐methyl phenyl methacrylate/8‐quinolinyl methacrylate copolymers
Authors: Patel Milan V. , Patel Jatin N. , Ray Arabinda , Patel Rajni M.
Published: November 2004

4‐Chloro‐3‐methyl phenyl methacrylate (CMPM) and 8‐quinolinyl methacrylate (8‐QMA) were synthesized through the reaction of 4‐chloro‐3‐methyl phenol and 8‐hydroxy quinoline, respectively, with methacryloyl chloride. The homopolymers and copolymers were prepared by free‐radical polymerization with azobisisobutyronitrile as the initiator at 70 °C. Copolymers of CMPM and 8‐QMA of different compositions were prepared. The monomers were characterized with IR spectroscopy and 1H NMR techniques. The copolymers were characterized with IR spectroscopy. UV spectroscopy was used to obtain the compositions of the copolymers. The monomer reactivity ratios were calculated with the Fineman–Ross method. The molecular weights and polydispersity values of the copolymers were determined with gel permeation chromatography. The thermal stability of the polymers was evaluated with thermogravimetric analysis under a nitrogen atmosphere. The homopolymers and copolymers were tested for their antimicrobial activity againstbacteria, fungi, and yeast. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 157–167, 2005
Synthesis of photosensitive and thermosetting poly(phenylene ether) based on poly[2,6‐di(3‐methyl‐2‐butenyl)phenol‐co‐2,6‐dimethyl‐phenol] and a photoacid generator
Authors: Matsumoto Kazuya , Shibasaki Yuji , Ando Shinji , Ueda Mitsuru
Published: November 2004

A chemically amplified photosensitive and thermosetting polymer based on poly[2,6‐di(3‐methyl‐2‐butenyl)phenol (15 mol %)‐co‐2,6‐dimethylphenol (85 mol %)] (3c) and a photoacid generator [(5‐propylsulfonyloxyimino‐5H‐thiophen‐2‐ylidene)‐(2‐methylphenyl)acetonitrile] was developed. Poly[2,6‐bis(3‐methyl‐2‐butenyl)phenol]‐co‐2,6‐dimethylphenol)] (3) with high molecular weights (number‐average molecular weight ∼ 24,000) was prepared by the oxidative coupling copolymerization of 2,6‐di(3‐methyl‐2‐butenyl)phenol with 2,6‐dimethylphenol in the presence of copper(I) chloride and pyridine as the catalyst under a stream of oxygen. The structures of 3 were characterized with IR, 1H NMR, and 13C NMR spectroscopy. 3 was crosslinked by a thermal treatment at 300 °C for 1 h under N2. The 5% weight loss temperatures and glass‐transition temperatures of the cured copolymers reached around 420 °C in nitrogen and 300 °C, respectively. The average refractive index of the cured copolymer (3c) film was 1.5452, from which the dielectric constant at 1 MHz was estimated to be 2.6. The resist showed a sensitivity of 35 mJ cm−2 and a contrast of 1.6 when it was exposed to 436‐nm light, postexposure‐baked at 145 °C for 5 min, and developed with toluene at 25 °C. A fine negative image featuring 8‐μm line‐and‐space patterns was obtained on a film exposed to 100 mJ cm−2 with 436‐nm light in the contact‐printed mode. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 149–156, 2005
Synthesis, characterization, and application of melamine‐based dendrimers supported on silica gel
Authors: Acosta Erick J. , Gonzalez Sergio O. , Simanek Eric E.
Published: November 2004

Dendrimers based on melamine have been covalently attached to silica gel with convergent and divergent approaches. These approaches yield different products. Each step of the synthesis can be monitored with Fourier transform infrared spectroscopy, thermal gravimetric analysis, and X‐ray photoelectron spectroscopy. The organic molecules can be isolated by chemical etching the organosilica material with HF and then analyzed by mass spectrometry. The convergent approach, which relies on the solution‐phase synthesis of the dendrimer before its attachment onto silica gel, produces materials that are ∼20% w/w organic regardless of the generation of the dendrimer used in the preparation of these composites and without apparent defects in the dendrimer structure. Materials prepared with the divergent approach show increasing percentages of organic material with each generation, but the dendrimers show structural defects including incomplete branching. In a survey of sequestration potential, materials obtained with the divergent approach removed more atrazine from solution than the more homogeneous materials obtained from the convergent approach. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 168–177, 2005
Microemulsion copolymerization of styrene and acrylonitrile with n‐butanol as the cosurfactant
Authors: Shi Yuanchang , Wu Youshi , Hao Jingcheng , Li Ganzuo
Published: November 2004

The microemulsion copolymerization of styrene and acrylonitrile in an n‐butanol/cetyltrimethylammonium bromide/oil/water microemulsion system was studied. The solubilization sites of the two monomers were determined with an NMR technique. The results showed that the solubilization behaviors of the two monomers were quite different. Most of the styrene was solubilized in the palisade layer of the microemulsion, whereas the acrylonitrile had an equilibrium distribution in the aqueous phase and palisade layer of the microemulsion. The reactivity ratios of styrene and acrylonitrile in the microemulsion system were different from those in other media. The effect of the monomer feed composition on the copolymerization kinetics was investigated, and the mechanism of nucleation of the latex particles was examined. The experimental results showed that the copolymerization loci were changed from the microemulsion droplets to the aqueous phase when the concentration of acrylonitrile in the monomer feed reached approximately 80%; this could be further proved by the effect of the monomer feed composition on the copolymerization kinetics. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 203–216, 2005
Evolution of the termination rate coefficient in styrene polymerization
Authors: Arcos‐Casarrubias José Antonio , Olayo Roberto , Bernechea Jaime Noriega
Published: November 2004

Styrene bulk polymerization was conducted at 70 °C with a high initiator concentration, and this ensured that the dominant chain‐stopping mechanism was the combination of free radicals. The evolution of the molecular weight distribution (MWD) of the polymer was measured via the periodic removal of samples during the course of the reaction and their analysis with gel permeation chromatography. The overall termination rate coefficient was independent of the conversion in the dilute regime, as observed from cumulative MWDs. In the middle of the conversion range, the observed trend was compatible with a translational‐diffusion‐controlled mechanism for the termination step. A bimodal distribution of the molecular weights was also found at high conversions and could be explained in terms of an increase in the free‐radical concentration and a very low termination rate coefficient. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 178–187, 2005
Issues in high‐throughput comparative modelling: A case study using the ubiquitin E2 conjugating enzymes
Authors: Winn P.J. , Battey J.N.D. , Schleinkofer K. , Banerjee A. , Wade R.C.
Published: November 2004

Sequences of the ubiquitin‐conjugating enzyme (UBC or E2) family were used as a test set to investigate issues associated with the high‐throughput comparative modelling of protein structures. A semi‐automatic method was initially developed with particular emphasis on producing models of a quality suitable for structural comparison. Structural and sequence features of the E2 family were used to improve the sequence alignment and the quality of the structural templates. Initially, failure to correct for subtle structural inconsistencies between templates lead to problems in the comparative analysis of the UBC electrostatic potentials. Modelling of known UBC structures using Modeller 4.0 showed that multiple templates produced, on average, no better models than the use of just one template, as judged by the root‐mean‐squared deviation between the comparative model and crystal structure backbones. Using four different quality‐checking methods, for a given target sequence, it was not possible to distinguish the model most similar to the experimental structure. The UBC models were thus finally modelled using only the crystal structure template with the highest sequence identity to the target to be modelled, and producing only one model solution. Quality checking was used to reject models with obvious structural anomalies (e.g., bad side‐chain packing). The resulting models have been used for a comparison of UBC structural features and of their electrostatic potentials. The work was extended through the development of a fully automated pipeline that identifies E2 sequences in the sequence databases, aligns and models them, and calculates the associated electrostatic potential. Proteins 2005. © 2004 Wiley‐Liss, Inc.
PhosphaBase: An ontology‐driven database resource for protein phosphatases
Authors: Wolstencroft K. J. , Stevens R. , Tabernero L. , Brass A.
Published: November 2004

PhosphaBase is an ontology‐driven database resource containing information on the protein phosphatase family. It is the first public resource dedicated to protein phosphatases, which are enzymes that perform dephosphorylation reactions. In conjunction with the phosphorylation action of protein kinases, phosphatases are involved in important control and communication mechanisms in the cell. They have also been implicated in many human diseases, including diabetes and obesity, cancers, and neurodegenerative conditions. PhosphaBase aims to centralize the growing base of knowledge in the phosphatase research domain. The resource is built around a formal, domain‐specific DAML+OIL ontology, and the data are collected from heterogeneous biological sources using Gene Ontology terms as a means of data extraction. The overall ontology‐driven architecture provides a robust structure with distinct advantages for sustainability and provides the potential for the development of diagnostic tools, as well as a data repository. Proteins 2005. © 2004 Wiley‐Liss, Inc.
Analysis of residues of imidacloprid in tobacco by high‐performance liquid chromatography with liquid–liquid partition cleanup
Authors: Liu Hongxia , Song Juanmei , Zhang Shusheng , Qu Lingbo , Zhao Yufen , Wu Yangjie , Liu Huimin
Published: November 2004

A practical method for analysis of residues of imidacloprid in baked tobacco leaves has been developed using HPLC with liquid–liquid partition clean‐up. Imidacloprid was extracted with ethyl acetate under ultrasound, and cleaned up by liquid–liquid partition with 50 g litre−1 aqueous sodium chloride followed by dichloromethane. The water‐soluble and fat‐soluble components in tobacco, which interfere with imidacloprid in HPLC, were removed. The separation was performed on a Supelco LC‐18 column (250 mm × 4.6 mm ID) with a mobile phase of acetonitrile + 5 mM ammonium acetate (20 + 80 by volume) at a flow‐rate of 1 ml min−1. The baseline separation between imidacloprid and the tobacco blank was achieved within 10 min. With a detection wavelength at 270 nm, the limit of quantitation was 0.04 mg kg−1. The recovery ranged from 89.8 to 95.4% and the RSDs were less than 2.3%. The proposed method was successfully employed for the determination of imidacloprid residues in 300 samples of flue‐cured tobacco leaves. Copyright © 2004 Society of Chemical Industry
High‐order Stokes and anti‐Stokes Raman generation in CVD diamond
Authors: Kaminskii A. A. , Ralchenko V. G. , Konov V. I. , Eichler H. J.
Published: November 2004

We report the first observation of nonlinear lasing effects – stimulated Raman scattering (SRS) in synthetic polycrystalline diamond grown by the chemical vapor deposition technique. We classify this material as a promising χ(3)‐active medium for new generation of Raman laser converters.
Quasi‐localized low‐frequency vibrational modes of disordered solids: Study by single‐molecule spectroscopy
Authors: Naumov A. V. , Vainer Yu. G. , Bauer M. , Kador L.
Published: November 2004

Editor's Choice of this issue of physica status solidi (b) is the article [1] by Andrei V. Naumov et al. This paper is Part II (Part I see [2]) of a study on elementary excitations in glasses, presented at the 11th International Conference on Phonon Scattering in Condensed Matter, St. Petersburg, 25–30 July 2004. For his outstanding talk, Naumov received the new physica status solidi Young Researcher Award which was bestowed for the first time at this conference.

The cover picture is a sketch of a glass with a single impurity molecule and one hypothetical quasi‐localized vibrational mode. The broadening and shift of the chromophore spectral line are caused by the interaction with this mode.

Andrei V. Naumov is senior scientific researcher and deputy head of the Molecular Spectroscopy Department of the Institute of Spectroscopy, Troitsk. His main research interests are experimental and theoretical studies of low‐temperature dynamics of amorphous solids (glasses, polymers etc.) via high resolution laser selective spectroscopy techniques.

The second Editor's Choice is an article by E. A. Eliseev and M. D. Glinchuk [3]. Eugene A. Eliseev is scientific researcher at the Frantsevich Institute for Problems of Materials Science of the Ukrainian National Academy of Sciences, Kiev. His research areas are the theory of size and correlation effects in ferroelectric materials as well as modelling of disordered ferroelectrics properties. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
NIST risk assessment for Part 11 compliance: Evaluation of a GXP case study
Authors: Fanjoy Monica
Published: November 2004

Current guidance for compliance with 21 Code of Federal Regulations (CFR) Part 11 requires a risk‐based approach that is justified, documented, and addresses potential product quality and safety risks. Based on this guidance, different risk assessment methods can be used to comply with Part 11. This study presents a risk assessment of a Part 11‐regulated computerized system using the techniques presented in the first public draft of the National Institute of Standards and Technology's (NIST) Risk Management Guide for Information Technology Systems. Results of this case study evaluation suggest that GXP‐regulated industries might strengthen their overall risk management and compliance activities by adopting the NIST framework; however, they would need to address these three challenges: terminology differences, unclear direction with regards to product safety risks, and cumbersome documentation in the regulated environment. Copyright © 2004 John Wiley & Sons, Ltd.
Standard Operating Procedures for clinical research personnel ‐ Part 22
Authors: Bohaychuk Wendy , Graham Ball C. D.
Published: November 2004

This is the twenty‐second part in a series of articles containing proposals for wording and content of Standard Operating Procedures (SOPs) for clinical research activities conducted by Sponsors and Contract Research Organisations (CROs). The procedures include those required by the International Conference on Harmonisation (ICH), the Food and Drug Administration (FDA), many other guidelines and regulations, and ‘best practice’ observed by the authors. The model forms require modification for actual use. In this article, SOPs are presented for final activities for closure of a clinical study: study site closure (SOP 701) and premature termination or suspension of clinical studies (SOP 702). More SOPs related to study closure will appear in the next issue of QAJ. (The full text of all 101 SOPs is available from the authors.) Copyright © 2004 John Wiley & Sons, Ltd.
Quality control of documents under the constraint of limited resources ‐ maximising the value of QC
Authors: Woolley Paul , Seiler Walther , Kühn Andrea
Published: November 2004

We describe a principle of reviewing documents, particularly those relating to clinical studies, under constraints of time and/or manpower. This principle can be expressed formally in a manner that shows how to choose which processes to conduct and which to jettison, when external constraints prohibit the performance of all quality control (QC) steps with arbitrarily great thoroughness. We classify the major steps in reviewing clinical study documents on this basis, thus providing suggested ‘do’s and ‘don’t's for planning QC of documents. However, to optimise the value of a QC review under the constraint of limited resources, it is important to rank the tasks according to their utility for the document's value, and this may require procedures to be refined on a project‐by‐project basis. Copyright © 2004 John Wiley & Sons, Ltd.
Quality improvement within Institutional Review Boards
Authors: Sansone Randy A. , McDonald Stephen
Published: November 2004

Quality Assurance or Quality Improvement (QA/QI) programs are an internal means of evaluating organizational performance. While the QA/QI process exists in many organizations, it is less common among Institutional Review Boards (IRBs), whose function is to review all research activities in an institution with regard to patient safety. Several studies offer examples of rudimentary QA/QI efforts in the area of IRB stipulations (required revisions to research submissions), which appear to be the initial frontiers of such activities for IRBs. However, broader types of activities might be undertaken by IRBs and these activities may now be guided by several organizations. Copyright © 2004 John Wiley & Sons, Ltd.
A guideline for specifying compliance in multi‐fingered operations
Authors: Kim Byoung‐Ho , Yi Byung‐Ju , Oh Sang‐Rok , Suh Il Hong
Published: November 2004

In this paper, we present a fundamental compliance analysis for multi‐fingered hands and also provide a guideline for specifying compliance characteristics in the three‐dimensional operational space of multi‐fingered hands. Through the analysis of the stiffness relation between the operational space and the fingertip space of multi‐fingered hands, it is shown that some of the coupling stiffness elements cannot be planned arbitrarily. Also, an independent finger‐based compliance control method to achieve the given compliance characteristics is described. Conclusively, when we specify the operational stiffness matrix, the contents of the operational stiffness matrix cannot be fully achieved by influence of the grasp geometry of multi‐fingered hands. The grasp positions of fingers as well as the RCC point, which are shown important factors, should be chosen to achieve the specified operational stiffness matrix for the given task. The cases of a point contact with friction and soft contact are examined as illustrative examples. It is observed that a five‐fingered robotic hand is sufficient for implementation of proper three‐dimensional compliance characteristics. © 2004 Wiley Periodicals, Inc.
Dynamics modeling and analysis of a biped walking robot actuated by a closed‐chain mechanism
Authors: Choi Hyeung‐Sik , Baek Changyul
Published: November 2004

We developed a new type of human‐sized biped walking robot (BWR) driven by the closed‐chain type of joint actuator. Each leg of the robot is composed of three pitch joints and one roll joint. In all, a 15 degree‐of‐freedom robot including four arm joints and three joints for the head was developed. The BWR was developed to walk autonomously such that all leg joints are actuated by small 90 W dc motors/drivers and dc batteries and controllers which are boarded. The joint actuator for the BWR is composed of the four‐bar‐link mechanism driven by the ball screw which has high strength and high gear ratio. A dynamics modeling of the developed BWR for forward walking is presented in which the revolute joint dynamics are transformed into the prismatic joint dynamics of the ball screw. Also, an analysis on the four‐bar‐link mechanism applied to the joint actuator and on the structure of the BWR is shown. The design specification of the actuating motor for the BWR is analyzed through the torque analysis of the four‐bar‐link actuator. Through walking experiments of the BWR, the walking performance and trajectory tracking ability is shown. © 2004 Wiley Periodicals, Inc.
Design of a reconfigurable planar parallel manipulator
Authors: Fisher R. , Podhorodeski R. P. , Nokleby S. B.
Published: November 2004

This work presents the design of a reconfigurable planar parallel manipulator (RPPM). The RPPM is designed to act as a testbed manipulator for theories on redundant actuation of parallel manipulators and can reconfigure into three different revolute‐jointed mechanism types: a 2‐branch 2‐DOF (degree‐of‐freedom) 5‐bar mechanism; a 2‐branch 3‐DOF 6‐bar mechanism; and a 3‐branch 3‐DOF 8‐bar mechanism. The design of the RPPM allows for any shoulder or elbow joint to be actuated. In this work, the criteria and constraints of the design are presented. The final design of the RPPM is shown, followed by a discussion of the final design and how it relates to the initial design criteria and constraints. © 2004 Wiley Periodicals, Inc.