bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predicting heat inactivation of Staphylococcus aureus under nonisothermal treatments at different pH
Authors: Hassani Mounir , Mañas Pilar , Condón Santiago , Pagán Rafael 
Published: May 2006

AbstractThe aim was to assess whether heat resistance data obtained from isothermal treatments allow the estimation of survivors of Staphylococcus aureus under nonisothermal conditions and to find a model that accurately predicts its heat inactivation at constantly rising heating rates (0.5–9°C/min) in media of different pH (4.0–7.4). S. aureus showed a higher heat resistance under isothermal treatments at pH 4.0 than at pH 5.5–7.4. However, under nonisothermal treatments S. aureus increased its heat resistance at pH 5.5–7.4 and became more thermotolerant than at pH 4.0. Estimations of survival curves under nonisothermal treatments obtained from heat resistance parameters of isothermal treatments did not adequately fit experimental values. Whereas the number of survivors was much higher than estimated at pH 5.5–7.4, that obtained at the slower heating rates at pH 4.0 was lower. An equation based on the Weibullian‐like distribution (log10S(t) = (t/δ)p) accurately described survival curves obtained under nonisothermal conditions. A nonlinear relationship was observed among the scale parameter (δ) and the heating rate which allowed the development of two equations capable of predicting the inactivation rate of S. aureus under nonisothermal treatments. This study might contribute to prevent public health risks in foods requiring long heating lag phases during their processing.
Evidence of a new dechlorinated ochratoxin A derivative formed in opossum kidney cell cultures after pretreatment by modulators of glutathione pathways: Correlation with DNA‐adduct formation
Authors: Faucet‐Marquis Virginie , Pont Frédéric , Størmer Frederik C. , Rizk Toufik , Castegnaro Marcel , Pfohl‐Leszkowicz Annie 
Published: May 2006

AbstractOchratoxin A (OTA), a nephrotoxic mycotoxin probably implicated in human Balkan endemic nephropathy and associated urothelial tumors, induces renal carcinomas in rodents and nephrotoxicity in pigs. OTA induces DNA‐adduct formation, but the structure of the adducts and their role in nephrotoxicity and carcinogenicity have only partly been elucidated. In vivo, 2‐mercaptoethane sulfonate (MESNA) protects rats against OTA‐induced nephrotoxicity but not against carcinogenicity, indicating two different mechanisms leading to nephrotoxicity or carcinogenicity. To better understand how DNA‐adduct could be generated, opossum kidney cells (OK) have been treated by OTA alone or in presence of several compounds such as MESNA or N‐acetylcysteine (another agent that, like MESNA, reduces oxidative stress by increasing of free thiols in kidney), buthionine sulfoximine (BSO) (an inhibitor of glutathione‐synthase), and alpha amino‐3‐chloro‐4,5‐dihydro‐5‐isoxazole acetic acid (ACIVICIN) (an inhibitor of gamma glutamyl transpeptidase). Cytotoxicity of OTA on OK cells was evaluated by applying the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay. None of the listed agents diminished OTA cytotoxicity significantly; ACIVICIN even increases OTA cytotoxicity. In contrast, analysis of the HPLC profiles of OTA metabolites produced during these incubations indicated that the pattern, the quantity of metabolites, and the nature of the derivatives were modulated by these agents. Ochratoxin B (OTB), open‐ring ochratoxin A (OP‐OA), 4 hydroxylated OTA, 10 hydroxylated OTA, OTA without phenylalanine, OTB without phenylalanine, and a dechlorinated OTA metabolite could be identified by nano‐ESI‐IT‐MS.
Advantages and drawbacks of immunoaffinity columns in analysis of mycotoxins in food
Authors: Castegnaro Marcel , Tozlovanu Marianna , Wild Christopher , Molinié Anne , Sylla Abdoulay , Pfohl‐Leszkowicz Annie 
Published: May 2006

AbstractA number of countries are setting legislations on mycotoxins. In order to reduce dispute between importing and exporting countries, the analytical data should be as comparable as possible, especially when levels are close to the regulatory limits. The present trend in the analysis of mycotoxins is to use immunoaffinity column (IAC) as a clean‐up and enrichment technique, and Association of Official Analytical Chemists and European Union have validated methods which address a few food commodities. This study describes our experience using both conventional and IAC approaches in the analysis of three mycotoxins. Aflatoxins (AFs): Aflatoxin G1 has been detected by liquid–liquid partitioning methods with HPLC detection as false‐positive in some maize. On IACs, this compound behaves as an AF, lowering the amount of the AFs trapped. The problem was solved using either TLC or HPLC with detection in the Kobra cell®. Depending on the additives to food during the processing and cooking, the AFs might appear as an opened ring not recognised by the antibody. Fumonisins (FB): Compounds interfering with the FB's antibodies were also observed while analysing breakfast cereals leading to underestimation of FB. Ochratoxin A (OTA): Depending on the food composition and extraction techniques, OTA is underestimated with IAC in some breakfast cereals and coffee. These data strengthen the necessity to validate methods using IAC for each complex matrix.
Computed coupling constants in X(CH3)nH(4–n) moieties where X = 13C and 15N+, and n = 0–4: comparisons with experimental data
Authors: Jimeno María‐Luisa , Alkorta Ibon , Elguero José , Del Bene Janet E. 
Published: May 2006

AbstractSeventy‐three unique spin–spin coupling constants have been analyzed for the ten species in the two series X(CH3)nH4–n, where the central atom X is 13C or 15N+. Thirty‐seven experimental values have been obtained from the literature, and several new coupling constants have been measured for the methyl‐substituted ammonium ions. Both DFT with the B3LYP functional and ab initio EOM‐CCSD calculations have been carried out on these same systems. Coupling constants computed by these two methods are in agreement with experimental values. Some problems related to coupling constants for the cationic ammonium systems have been resolved when these were recomputed at EOM‐CCSD for complexes in which NH4+ is hydrogen‐bonded to H2O molecules. Copyright © 2006 John Wiley & Sons, Ltd.
Genetic risk factors associated with lipid‐lowering drug‐induced myopathies
Authors: Vladutiu Georgirene D. , Simmons Zachary , Isackson Paul J. , Tarnopolsky Mark , Peltier Wendy L. , Barboi Alexandru C. , Sripathi Naganand , Wortmann Robert L. , Phillips Paul S. 
Published: May 2006

AbstractLipid‐lowering drugs produce myopathic side effects in up to 7% of treated patients, with severe rhabdomyolysis occurring in as many as 0.5%. Underlying metabolic muscle diseases have not been evaluated extensively. In a cross‐sectional study of 136 patients with drug‐induced myopathies, we report a higher prevalence of underlying metabolic muscle diseases than expected in the general population. Control groups included 116 patients on therapy with no myopathic symptoms, 100 asymptomatic individuals from the general population never exposed to statins, and 106 patients with non–statin‐induced myopathies. Of 110 patients who underwent mutation testing, 10% were heterozygous or homozygous for mutations causing three metabolic myopathies, compared to 3% testing positive among asymptomatic patients on therapy (P = 0.04). The actual number of mutant alleles found in the test group patients was increased fourfold over the control group (P < 0.0001) due to an increased presence of mutation homozygotes. The number of carriers for carnitine palmitoyltransferase II deficiency and for McArdle disease was increased 13‐ and 20‐fold, respectively, over expected general population frequencies. Homozygotes for myoadenylate deaminase deficiency were increased 3.25‐fold with no increase in carrier status. In 52% of muscle biopsies from patients, significant biochemical abnormalities were found in mitochondrial or fatty acid metabolism, with 31% having multiple defects. Variable persistent symptoms occurred in 68% of patients despite cessation of therapy. The effect of statins on energy metabolism combined with a genetic susceptibility to triggering of muscle symptoms may account for myopathic outcomes in certain high‐risk groups. Muscle Nerve, 2006
Global ratings of patient satisfaction and perceptions of improvement with treatment for urinary incontinence: Validation of three global patient ratings
Authors: Burgio Kathryn L. , Goode Patricia S. , Richter Holly E. , Locher Julie L. , Roth David L. 
Published: May 2006

AbstractAimsTo test the validity of three patient global ratings, satisfaction, perception of improvement, and estimated percent improvement, for measuring outcomes of behavioral treatment for urinary incontinence.MethodsThis report is a secondary analysis of data from three randomized controlled trials testing behavioral interventions for incontinence. Participants were 359 community‐dwelling women, aged 40–92 years, with stress, urge, or mixed urinary incontinence. All participants received an 8‐week program of clinic‐based or self‐administered behavioral training. Subjective outcomes included a patient satisfaction question (PSQ), global perception of improvement (GPI), and estimated percent improvement (EPI). Convergent validity was tested by examining the relationship between each measure and reduction of incontinence (bladder diary), change on the incontinence impact questionnaire (IIQ), and desire for another treatment. Discriminant validity was explored by examining the relationship of the global ratings to five measures not expected to be related to outcome (age, race, BMI, education level, and change in perceived pain).ResultsAll three patient global ratings were significantly associated with each other (P < 0.0001), with diary measures of reduction of incontinence episodes (P < 0.0001), and change in the IIQ (P < 0.005), and inversely associated with desire for another treatment (P < 0.0001). All three patient ratings were not significantly associated with age, race, BMI, education level, or change in perceived pain.ConclusionPatient global ratings of satisfaction, perception of improvement, and estimated percent improvement have acceptable convergent and discriminant validity for measuring outcomes in studies of behavioral treatment for urinary incontinence. Neurourol. Urodynam. Published 2006 Wiley‐Liss, Inc.
Construct validity of the incontinence severity index
Authors: Murphy Miles , Culligan Patrick J. , Arce Cristina M. , Graham Carol A. , Blackwell Linda , Heit Michael H. 
Published: May 2006

AbstractAimsTo assess the construct validity of the incontinence severity index (ISI) by testing its correlation with two health‐related quality of life measures, the short forms of the Urogenital Distress Inventory (UDI‐6) and the Incontinence Impact Questionnaire (IIQ‐7), in women with urodynamic stress incontinence.Materials and MethodsA cohort of 170 women with the urodynamic stress incontinence who underwent corrective surgery completed the ISI, IIQ‐7, and the UDI‐6 both pre‐ and post‐treatment. We correlated the pre‐ and post‐treatment responses between the ISI, the IIQ‐7, the UDI‐6 and their subscales. We also assessed the sensitivity of the ISI to change by correlating the percent change in score between the three instruments. The results were analyzed using a non‐parametric test of correlation, the Spearman's rho.ResultsThe ISI scores were generally not well correlated with the pre‐treatment IIQ‐7 and UDI‐6 scores (r < 0.40). The post‐treatment scores and percent change from pre‐ to post‐treatment of the ISI, however, were highly correlated with that of the IIQ‐7 and UDI‐6 (r's > 0.70, P < 0.001). The ISI was most highly correlated with the UDI‐6 stress symptoms subscale and most poorly correlated with the UDI‐6 obstructive/discomfort subscale.ConclusionsThis study provides valuable insight into the construct validity of the ISI. Evidence of its convergent validity is found in the high correlation with the stress symptoms subscales of the UDI‐6, while the poorer correlation with the obstructive subscale provides evidence of its divergent validity. These data also suggest that the ISI is highly sensitive to change seen with treatment. Neurourol. Urodynam. 25:418–423, 2006. © 2006 Wiley‐Liss, Inc.
Photo‐differential scanning calorimetry study on photopolymerization of nanosized titanium dioxide/polyacrylate hybrid materials
Authors: Tao Wan , Fei Feng , Rong Ran , Yue‐Chuan Wang 
Published: May 2006

AbstractNanosized titania–polyacrylate hybrid films were prepared by controlled hydrolysis of titanium tetrabutoxide (TTB) in Span 85/Tween 80 reverse micelles as well as rapid entrapment of nanosized particles by subsequent photopolymerization. This work focused on the characterization of the photopolymerization of the transparent hybrid films via photocalorimetry. The polymerization kinetics of several mixtures of mono‐ and di‐functional acrylate monomers were compared to examine the effect of average functionality. Further, Effects of [H2O]/[surfactant] molar value and TTB concentration on photopolymerization kinetics were also studied. X‐ray photoelectron spectra and FTIR demonstrated the formation of TiO2 in the hybrid films. Atomic Force Microscope (AFM) images showed the inorganic domains with mean sizes of 25 nm were uniformly dispersed in the polymeric networks. Copyright © 2006 Society of Chemical Industry
Chemical natures and distributions of metal impurities in multicrystalline silicon materials
Authors: Buonassisi T. , Istratov A. A. , Pickett M. D. , Heuer M. , Kalejs J. P. , Hahn G. , Marcus M. A. , Lai B. , Cai Z. , Heald S. M. , Ciszek T. F. , Clark R. F. , Cunningham D. W. , Gabor A. M. , Jonczyk R. , Narayanan S. , Sauar E. , Weber E. R. 
Published: May 2006

AbstractWe present a comprehensive summary of our observations of metal‐rich particles in multicrystalline silicon (mc‐Si) solar cell materials from multiple vendors, including directionally‐solidified ingot‐grown, sheet, and ribbon, as well as multicrystalline float zone materials contaminated during growth. In each material, the elemental nature, chemical states, and distributions of metal‐rich particles are assessed by synchrotron‐based analytical x‐ray microprobe techniques. Certain universal physical principles appear to govern the behavior of metals in nearly all materials: (a) Two types of metal‐rich particles can be observed (metal silicide nanoprecipitates and metal‐rich inclusions up to tens of microns in size, frequently oxidized), (b) spatial distributions of individual elements strongly depend on their solubility and diffusivity, and (c) strong interactions exist between metals and certain types of structural defects. Differences in the distribution and elemental nature of metal contamination between different mc‐Si materials can largely be explained by variations in crystal growth parameters, structural defect types, and contamination sources. Copyright © 2006 John Wiley & Sons, Ltd.
Synthesis and characterization of new radiopaque microspheres by the dispersion polymerization of an iodinated acrylate monomer for X‐ray imaging applications
Authors: Galperin Anna , Margel Shlomo 
Published: May 2006

AbstractRadiopaque microspheres of sizes ranging from 0.2 to 1.4 μm were formed by the dispersion polymerization of the monomer 2‐methacryloyloxyethyl(2,3,5‐triiodobenzoate) in 2‐methoxyethanol. The effects of various polymerization parameters, including the monomer concentration, initiator type and concentration, and stabilizer molecular weight and concentration, on the molecular weight, size, and size distribution of the particles were elucidated. The characterization of these iodinated microspheres was accomplished with routine methods such as Fourier transform infrared, nuclear magnetic resonance, thermogravimetric analysis, differential scanning calorimetry, gel permeation chromatography, scanning electron microscopy, Brunauer–Emmett–Teller measurements, and elemental analysis. Because of the presence of iodine atoms in these microspheres, they were expected to possess a radiopaque nature. The radiopacity of these particles dispersed in water and in the dry state was demonstrated with an imaging technique based on X‐ray absorption usually used in hospitals. These novel radiopaque microspheres may be used for different X‐ray imaging needs, such as blood pooling, body organs, embolization, dental compositions, implants, prostheses, and nanocomposites. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3859–3868, 2006
Synthesis and self‐assembly of polystyrene‐grafted multiwalled carbon nanotubes with a hairy‐rod nanostructure
Authors: Yang Yingkui , Xie Xiaolin , Wu Jingao , Mai Yiu‐Wing 
Published: May 2006

AbstractPolystyrene‐grafted multiwalled carbon nanotubes (PS‐g‐MWNTs) with a hairy‐rod nanostructure were synthesized by the in situ free‐radical polymerization of styrene in the presence of multiwalled carbon nanotubes (MWNTs) terminated with vinyl groups. To quantitatively study the molecular weight and composition of polystyrene (PS) chains in PS‐g‐MWNTs, PS‐g‐MWNTs were fully defunctionalized by hydrolysis. The results showed that 1 of every 100 carbon atoms in MWNTs was functionalized at the tips and outer walls of the carbon nanotubes and grafted by PS with a weight‐average molecular weight of 9800 g/mol; therefore, a uniform thin layer (ca. 8–10 nm) of a PS shell was formed on the outer wall of MWNTs. PS‐g‐MWNTs were soluble in dimethylformamide and tetrahydrofuran. The thermal stability and glass‐transition temperature of PS in PS‐g‐MWNTs were obviously increased. Nanopins were formed on the glass substrates by the self‐assembly of PS‐g‐MWNTs, and the dewetting effect between the glass substrate and PS chains covered MWNTs during the evaporation of the solution. Both the length and diameter of the nanopins increased with the solution concentration. When PS‐g‐MWNTs were compression‐molded, MWNTs were dispersed uniformly in the PS matrix and formed good networks, such as circlelike and starlike structures, because of the entanglements of hairy PS chains on MWNTs. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3869–3881, 2006
Mass spectrometrical verification of stomatin‐like protein 2 (SLP‐2) primary structure
Authors: Pradeep John Julius Paul , Anrather Dorothea , Pollak Arnold , Lubec Gert 
Published: May 2006

AbstractStomatin‐like protein 2 (SLP‐2) (syn.: EPB72‐like 2 [NP_038470], HSPC108 [AAF29073]), a protein of unknown function, has been described in several tissues and cells but its primary structure is still not completely elucidated. Moreover, sequence conflicts appear in several databases. It was the aim of the study to further describe SLP‐2 primary sequence and to solve existing sequence conflicts. For this purpose a protein extract was run on two‐dimensional gel electrophoresis and SLP‐2 was identified by MALDI‐TOF/TOF. SLP‐2 was digested with trypsin, chymotrypsin, Lys‐C, and de novo sequencing studies as well as Nano‐HPLC‐ESI‐MS/MS analysis were carried out. By the use of several proteases sequence coverage of 90% was obtained but the N‐terminal 34 amino acids harbouring database conflict 1 were not covered. The presence of Leucine 129 (sequence conflict 2) and Alanine 202 (sequence conflict 3) was verified by three independent approaches. High sequence coverage resulting from multiple proteolytic cleavage, MALDI‐TOF/TOF, Nano‐HPLC‐ESI‐MS/MS and de novo sequencing completed unambiguous analysis of SLP‐2 primary structure of ≈90% of sequence coverage. In addition, methodology used was able to solve so far pending sequence conflicts in databases and literature. SLP‐2 is a high abundance protein in several tissues and cells and may play an important biological role and therefore characterization of its primary structure is of importance. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Cover Picture: Rapid Research Letter – Focusing slabs made of negative index materials based on inhomogeneous dielectric rods
Authors: Sergentu V. V. , Ursaki V. V. , Tiginyanu I. M. , Foca E. , Föll H. , Boyd Robert W. 
Published: May 2006

AbstractIn the Rapid Research Letter [1] it is shown that a flat array of dielectric rods can act as a focusing lens of good quality – provided the rods have specified gradients of the dielectric constant. This design is superior to conventional photonic crystals (PC) utilizing homogeneous rods since the “lens” can be smaller and has better properties in a broader wavelength range.The cover picture is an artist's view of the PC lens made from dielectric rods consisting of three layers with the refractive index increasing from the margin to the center of the rod, focusing a light beam into a small spot. The focusing spot is controlled by the parameters of the rods and their arrangement in the PC slab.The first author, Dr. Vladimir Sergentu, is a senior researcher of the Laboratory of Low Dimensional Semiconductor Structures in Chisinau, Moldova, which works on the design of PC based optical elements in collaboration with the Universities of Kiel and Rochester.
Photoluminescence in implanted and doped silicon near room temperature
Authors: Matsubara Ichiro , Sasahara Shingo , Mishina Tomobumi , Ishibashi Yasuhiko , Kobayashi Toshihiko , Nakahara Jun'ichiro 
Published: May 2006

AbstractPhotoluminescence in implanted and doped silicon at room temperature is measured, and the observed structures are assigned as intrinsic phonon‐assisted indirect allowed transitions. The temperature of photoexcited carriers, which is higher than the bath temperature, is estimated. For confined carriers produced by boron implantation the temperature dependence of the effective temperature of the excited carriers is the same for the different samples, but an enhancement of the photoluminescence is observed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
1H NMR spin–lattice relaxation studies in Betaine phosphate (BP) – Transition from classical to quantum rotation
Authors: Ramanuja M. N. , Ramesh K. P. , Ramakrishna J. 
Published: May 2006

AbstractWe report here the results of our 1H NMR spin–lattice relaxation time (T 1) studies in betaine phosphate which is ferroelectric below 86 K and antiferroelectric below 81 K. The experiments have been carried out in the temperature range 300 to 4 K, at two Larmor frequencies 11.4 and 23.3 MHz. The T 1 data (300–100 K) has been analysed using modified BPP equation based on Ikeda's model. CH3 protons are found to relax other protons via spin diffusion. The low temperature (T < 100 K) T 1 data has been analysed following Lourens model which considers the gradual transition from classical motions to quantum regime. At low temperatures, when classical processes tend to freeze, reorienting groups apparently have minute differences and hence create a distribution in the energy values (E a and E 01) and pre‐exponential factors. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of off‐diagonal dielectric response on optical properties of LaTiO3
Authors: Krasovska O. V. , Antonov V. N. , Krasovskii E. E. , Schattke W. 
Published: May 2006

AbstractOptical spectra of LaTiO3 are analyzed on the basis of an ab initio macroscopic dielectric function. The energy band structure and microscopic dielectric matrix are calculated with the extended linear augmented plane wave (ELAPW)‐k · p method. The origin of UV spectral structures is elucidated. LaTiO3 is compared with SrTiO3 and BaTiO3 perovskites, and chemical trends in the formation of the UV reflectivity are discussed. The inclusion of local field corrections shifts spectral structures due to semi‐core La 5p and Ti 3p excitations by several eV to higher energies. Calculated reflectivity and optical conductivity curves agree well with the experiment. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)