bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mutations in the mitochondrial cytochrome b of Tetranychus urticae Koch (Acari: Tetranychidae) confer cross‐resistance between bifenazate and acequinocyl
Authors: Van Nieuwenhuyse Pieter , Van Leeuwen Thomas , Khajehali Jahangir , Vanholme Bartel , Tirry Luc 
Published: January 2009

AbstractBACKGROUND: Resistance of Tetranychus urticae Koch to bifenazate was recently linked with mutations in the mitochondrial cytochrome b Qo pocket, suggesting that bifenazate acts as a Qo inhibitor (QoI). Since these mutations might cause cross‐resistance to the known acaricidal QoI acequinocyl and fluacrypyrim, resistance levels and inheritance patterns were investigated in several bifenazate‐susceptible and bifenazate‐resistant strains with different mutations in the cd1 and ef helices aligning the Qo pocket.RESULTS: Cross‐resistance to acequinocyl in two bifenazate‐resistant strains was shown to be maternally inherited and caused by the combination of two specific mutations in the cytochrome b Qo pocket. Although most investigated strains were resistant to fluacrypyrim, resistance was not inherited maternally, but as a monogenic autosomal highly dominant trait. As a consequence, there was no correlation between cytochrome b genotype and fluacrypyrim resistance.CONCLUSIONS: Although there is no absolute cross‐resistance between bifenazate, acequinocyl and fluacrypyrim, some bifenazate resistance mutations confer cross‐resistance to acequinocyl. In the light of resistance development and management, high prudence is called for when alternating bifenazate and acequinocyl in the same crop. Maternally inherited cross‐resistance between bifenazate and acequinocyl reinforces the likelihood of bifenazate acting as a mitochondrial complex III inhibitor at the Qo site. Copyright © 2009 Society of Chemical Industry
Effect of different formulations on tebuconazole residues in stone fruits
Authors: Lucini Luigi , Molinari Gian Pietro 
Published: January 2009

AbstractBACKGROUND: The correlation between pesticide residue levels and formulation of an active substance is often not considered, even if it is reasonable to expect some differences arising from behaviour during dilution and spraying, from adhesion to plant and from degradation. An experimental study to investigate the magnitude of tebuconazole residues as a function of different tebuconazole formulated products was carried out in Italy. The fungicide was applied as wettable powder (WP) and water‐dispersible granule (WG) formulations to peach, plum, apricot and nectarine orchards, on four different sites. The fruit samples gained from the field trials were quantitatively analysed by gas chromatography with a nitrogen phosphorus detector (GC/NPD) for tebuconazole residues.RESULTS: Tebuconazole residues in the fruits gained from the plot treated with the WP formulation, 14 days after application, were in the range 0.01–0.07 mg kg−1, while corresponding residues in the plot treated with the WG formulation were in the range 0.01–0.06 mg kg−1.CONCLUSION: No significant differences in the residue levels of tebuconazole could be observed between the trials conducted with the WP and the WG formulation. Copyright © 2009 Society of Chemical Industry
Optical instabilities in semiconductor quantum‐well systems driven by phase‐space filling
Authors: Schumacher Stefan , Kwong N. H. , Binder R. , Smirl Arthur L. 
Published: January 2009

AbstractFour‐wave mixing (FWM) is one of the best known phenomena in semiconductor optics. Recent experimental results of FWM instabilities and optical switching in atomic systems have renewed the interest in FWM and possible related instabilities in semiconductors. We have recently performed theoretical investigations of FWM instabilities in a variety of semiconductor quantum well systems (single quantum wells, Bragg‐spaced multiple quantum wells, and planar semiconductor micocavities) and shown that different systems require different physical processes that potentially can give rise to FWM instabilities. In this contribution, we concentrate on the simple (and largely academic) finding that phase‐space filling together with spatial exciton dispersion can lead to FWM instabilities in single quantum wells. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Resveratrol attenuates 1,2‐dimethylhydrazine (DMH) induced glycoconjugate abnormalities during various stages of colon carcinogenesis
Authors: Sengottuvelan Murugan , Deeptha Kumaraswamy , Nalini Namasivayam 
Published: January 2009

AbstractAlthough a myriad of health promoting effects has been attributed to resveratrol (Res) (3,5,4′‐trihydroxy‐trans‐stilbene), a phytoalexin, the most interesting is its anticancer property. The aim of this work was to elucidate the effectiveness of Res against cellular transformation (glycoconjugate alterations) initiated by 1,2‐dimethylhydrazine (DMH), a colon specific carcinogen. Group 1 were control rats, group 2 were control rats that received Res (8 mg/kg body weight orally every day), rats in groups 3–6 were treated weekly with DMH (20 mg/kg body weight, subcutaneously × 15 times). In addition, groups 4–6 received Res (as in group 2) in three dietary regimens: initiation (I), post‐initiation (PI) and entire period (EP). At the end of the 30 week experimental period in DMH alone exposed rats, altered levels of glycoconjugates (total hexoses, fucose, hexosamine and sialic acid) were observed in liver, intestine and colon tissues. Of the three dietary regimens of Res, the entire period supplementation significantly (p < 0.01) modulated the levels of glycoconjugates and reduced the incidence of adenoma and adenocarcinoma. These findings suggest that Res may extend its chemopreventive effect by restoring the alteration in glycoconjugates that are thought to be involved in the colonic malignant transformation process in this experimental model. Copyright © 2009 John Wiley & Sons, Ltd.
Electron ionization mass spectrometric study of substituted alloxazine‐5‐oxides and iso‐alloxazine‐5‐oxide
Authors: Prukała Dorota , Sikorski Marek 
Published: January 2009

AbstractThe fragmentation pathways in electron ionization (EI) mass spectra of a series of new N(5)‐oxides of alloxazines and iso‐alloxazine are presented, and compared with those of substituted alloxazines and iso‐alloxazine. The EI mass spectra of these compounds showed characteristic fragmentation pathways A, B and C, started by the ejection of atomic oxygen, a HNCO molecule and an OH. radical, respectively. On the basis of B/E and B2/E spectra, the mechanism of elimination of the OH. radical is discussed. The influence of the methyl substituent in the benzene ring of alloxazine on the mass fragmentation pathways is described. Copyright © 2009 John Wiley & Sons, Ltd.
Comparison of atmospheric pressure photoionization and electrospray ionization mass spectrometry for the analysis of UV filters
Authors: Rodil Rosario , Schrader Steffi , Moeder Monika 
Published: January 2009

AbstractA comparison was made between the electrospray ionization (ESI) and atmospheric pressure photoionization (APPI) tandem mass spectrometric (MS/MS) responses of eleven ultraviolet (UV) filters. Four of the target compounds were favourably ionized in negative ion mode, and the other seven compounds in positive ion mode. For nine of the compounds APPI generated a similar response to that of ESI, but the APPI signal‐to‐noise (S/N) ratios were 1.3–60 times higher. The two most polar of the UV filter compounds (PBSA and BP‐4) were more efficiently ionized by ESI, offering higher signal intensities and lower detection limits. APPI was, however, less susceptible to ion suppression than ESI when real samples were injected. In order to optimize the APPI conditions different dopant solvents were examined to enhance the efficiency of the photoionization process. Among the evaluated dopants, toluene was selected as the best compromise. At a toluene flow rate of 10% of the solvent flow rates the ionization response increased by a factor of 40–50 over the use of no dopant for the compounds in positive ion mode and by more than 300 for the compounds in negative ion mode. Copyright © 2009 John Wiley & Sons, Ltd.
Imaging mass spectrometry for examining localization of polymeric composition in matrix‐assisted laser desorption/ionization samples
Authors: Weidner Steffen M. , Falkenhagen Jana 
Published: January 2009

AbstractThe localization of polymeric composition in samples prepared for matrix‐assisted laser desorption/ionization (MALDI) analysis has been investigated by imaging mass spectrometry. Various matrices and solvents were used for sample spot preparation of a polybutyleneglycol (PBG 1000). It was shown that in visibly homogeneous spots, prepared using the ‘dried droplet’ method, separation between matrix and polymer takes place. Moreover, using α‐cyano‐4‐hydroxycinnamic acid (CCA) as matrix and methanol as solvent molecular mass separation of the polymer homologues in the spots was detectable. In contrast to manually spotted samples, dry spray deposition results in homogeneous layers showing no separation effects. Copyright © 2009 John Wiley & Sons, Ltd.
Interaction of Guar and Xanthan Gums with Starch in the Gels Obtained from Normal, Waxy and High‐amylose Corn Starches
Authors: Weber Fernanda H. , Clerici Maria Teresa P. S. , Collares‐Queiroz Fernanda P. , Chang Yoon K. 
Published: January 2009

AbstractThe objectives of the present study were to analyze the chemical interactions between guar and xanthan gums and starches. Gels were obtained from normal (NCS), waxy (WCS) and high‐amylose (HACS) corn starches containing gums. The gels were evaluated according to their pasting properties and infra‐red absorption. The guar (GG) and xanthan (XG) gums affected the properties of the NCS paste more significantly than those of the WCS paste. In the infra‐red absorption spectra, no covalent bonds between the starches and gums were observed under the conditions studied, so probably the only interactions occurring between them were hydrogen bonds.
The Influence of Modified Starch on the Process Water Quality in Papermaking and the Paper Properties
Authors: Zakrajšek Nejc , Golob Janvit 
Published: January 2009

AbstractThe influence of modified (cationic) starch on the process water quality in papermaking and paper properties has been investigated. The experiments were conducted on sulfate hardwood pulp by applying both tap and paper mill process water. When process water is used, the retained amount of starch on fibers decreases, which most probably results from a partial neutralization of the cationic charge on modified starch, thereby reducing its attraction to the anionic groups on a fiber. By adding the modified starch, the turbidity of process water is to some extent reduced, indicating that the suspended organic substances are removed from process water. Due to starch accumulation, the load of process water by organic substances (determined via the TOC analysis) is not reduced, but is rather increased when the modified starch is added. In most cases, the addition of modified starch improved the investigated paper properties. However, these properties varied in correlation with the quality of the used water, despite the fact that the dosage of modified starch remained constant. This demonstrates the influence of process water quality, not only on the paper properties, but also on the efficiency of process chemicals, such as the modified starch, in the papermaking process.
Enabling system evolution through configuration management on the hardware/software boundary
Authors: Krikhaar René , Mosterman Wim , Veerman Niels , Verhoef Chris 
Published: January 2009

AbstractAs the use of software and electronics in modern products is omnipresent and continuously increasing, companies in the embedded systems industry face increasing complexity in controlling and enabling the evolution of their IT‐intensive products. Traditionally, product configurations and their updates were managed separately for the hardware and software discipline. At specified release moments during the development of their products, the hardware and software were released together. But, as the usage, flexibility and complexity of software and electronics increases, and fierce competition requires shorter time‐to‐market and customizable products, more frequent releases of integrated hardware and software configurations becomes necessary. This evolution requires adequate configuration management both within the hard‐ and software disciplines and across them. In many organizations, software configuration management is more visibly established than hardware configuration management due to the inherent flexibility and complexity of software. But as the flexibility of hardware has increased through the use of configurable hardware, the need for more intense hardware configuration management increased as well. To properly enable the evolution of integrated hardware/software systems, adequate configuration management is required in both disciplines. Our article deals with just that: configuration management on the hardware/software boundary, and is mainly focused on the product development phase. The hardware/software boundary has a broad scope; in this article we focus on embedded systems containing software and custom and off‐the‐shelf electronic hardware, thereby concentrating on configurable hardware containing both software and hardware designs. It is important to note that the concepts of our article apply to configuration management issues that go beyond that scope. We investigated the configuration management practices in six large organizations in the embedded systems industry, including medical devices, defense equipment, optics, document processing, and semiconductor equipment. In particular, we looked at programmable/configurable hardware, as the use and complexity of this technology continue to increase. We propose a generic development cycle with real‐life examples to illustrate the configuration management concepts. Then, from the sociotechnical design point of view, we raise awareness and argue that configuration management tools, processes, and its organization must be further aligned to support the complexity and interdisciplinary nature of the hardware/software boundary of evolving embedded systems. © 2009 Wiley Periodicals, Inc. Syst Eng
Microcystin extracts induce ultrastructural damage and biochemical disturbance in male rabbit testis
Authors: Liu Ying , Xie Ping , Qiu Tong , Li Hui‐Ying , Li Guang‐Yu , Hao Le , Xiong Qian 
Published: January 2009

AbstractIn the present research, the changes of ultrastructures and biochemical index in rabbit testis were examined after i.p. injection with 12.5 μg/kg microcystin (MC) extracts. Ultrastructural observation showed widened intercellular junction, distention of mitochondria, endoplasmic reticulum, and Golgi apparatus. All these changes appeared at 1, 3, and 12 h, but recovered finally. In biochemical analyses, the levels of lipid peroxidation (MDA) and H2O2 increased significantly at 1 h, indicating MC‐caused oxidative stress. Finally, H2O2 decreased to the normal levels, while MDA remained at high levels. The antioxidative enzymes (CAT, SOD, GPx, GST) and antioxidants (GSH) also increased rapidly at 1 h, demonstrating a quick response of the defense systems to the oxidative stress. Finally, the activity of CAT, SOD, and GPX recovered to the normal level, while the activity of GST and the concentration of GSH remained at a high level. This suggests that the importance of MCs detoxification by GST via GSH, and the testis of rabbit contained abundant GSH. The final recovery of ultrastructure and some biochemical indexes indicates that the defense systems finally succeeded in protecting the testis against oxidative damage. In conclusion, these results indicate that the MCs are toxic to the male rabbit reproductive system and the mechanism underlying this toxicity might to be the oxidative stress caused by MCs. Although the negative effects of MCs can be overcome by the antioxidant system of testis in this study, the potential reproductive risks of MCs should not be neglected because of their wide occurrence. © 2009 Wiley Periodicals, Inc. Environ Toxicol 2010.
Effect of single‐mineral filler and hybrid‐mineral filler additives on the properties of polypropylene composites
Authors: Nurdina A.K. , Mariatti M. , Samayamutthirian P. 
Published: January 2009

AbstractThe present study was carried out to determine the filler characteristics and to investigate the effects of three types of mineral fillers (CaCO3, silica, and mica) and filler loadings (10–40 wt%) on the properties of polypropylene (PP) composites. The characteristics of the particulate fillers, such as mean particle size, particle size distribution, aspect ratio, shape, and degree of crystallinity were identified. In terms of mechanical properties, for all of the filled PP composites, Young's modulus increased, whereas tensile strength and strain at break decreased as the filler loading increased. However, 10 wt% of mica in a PP composite showed a tensile strength comparable with that of unfilled PP. Greater tensile strength of mica/PP composites compared to that of the other composites was observed because of lower percentages of voids and a higher aspect ratio of the filler. Mica/PP also exhibited a lower coefficient of thermal expansion (CTE) compared to that of the other composites. This difference was due to a lower degree of crystallinity of the filler and the CTE value of the mica filler. Scanning electron microscopy was used to examine the structure of fracture surfaces, and there was a gradual change in tensile fracture behavior from ductile to brittle as the filler loading increased. The nucleating ability of the fillers was studied with differential scanning calorimetry, and a drop in crystallinity of the composites was observed with the addition of mineral filler. Studies on the hybridization effect of different (silica and mica) filler ratios on the properties of PP hybrid composites showed that the addition of mica to silica‐PP composites enhanced their tensile strength and modulus. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers
Retention of basic laparoscopic skills after a structured training program
Authors: Hiemstra E. , Kolkman W. , van de Put M. A. J. , Jansen F. W. 
Published: January 2009

AbstractThe purpose of this study was to test the retention of basic laparoscopic skills on a box trainer 1 year after a short training program. For a prior study, eight medical students without prior experience (novices) underwent baseline testing, followed by five weekly training sessions and a final test. During each of seven sessions, they performed five tasks on an inanimate box trainer. Scores were calculated by adding up the time to completion of the task with penalty points, consequently rewarding speed and precision. The sum score was the sum of the five scores. One year later, seven of them underwent retention testing for the current study. The final test results were compared with retention test results as a measure of durability of acquired skills. Novices’ scores did not worsen significantly for four out of five tasks (i.e., placing a pipe cleaner p = 0.46, placing beads p = 0.24, cutting a circle p = 0.31, and knot tying p = 0.13). However, deterioration was observed in the performance on stretching a rubber band (p < 0.05), as well as in the sum score (p < 0.05). Nevertheless, all retention scores remained better than the baseline results. In conclusion, basic laparoscopic skills acquired during a short training program merely sustain over time. However, ongoing practice is advisable, especially to preserve tissue-handling skills, since these may be the first to deteriorate.
The screening of SLC6A8 deficiency among Estonian families with X‐linked mental retardation
Authors: Puusepp H. , Kall K. , Salomons G. S. , Talvik I. , Männamaa M. , Rein R. , Jakobs C. , Õunap K. 
Published: January 2009

SummaryThe urinary creatine:creatinine (Cr:Crn) ratio was measured in males from 49 families with a family history compatible with X‐linked mental retardation (XLMR) in order to estimate the prevalence of SLC6A8 deficiency in Estonia. We identified 11 boys from 9 families with an increased urinary Cr:Crn ratio (18%). In three related boys, a hemizygous missense mutation (c.1271G>A; p.Gly424Asp) was identified. Their mother was heterozygous for the same mutation. Although many missense mutations have been described, the p.Gly424Asp mutation has not been previously reported. The clinical expression varied widely among affected males of this family. Patients 1 and 3 had relatively mild clinical expression (mild mental retardation (MR) and attention deficit disorder), but patient 2 had all typical clinical signs of SLC6A8 defect such as moderate MR, autistic features, expressive dysphasia and epilepsy. Among our patients, we saw significant problems in speech and language development combined with attention and behavioural difficulties. The number of false‐positive biochemical results with increased urinary Cr:Crn ratio was higher (18%) in our study than in previous reports (1.8–10%). We therefore suggest that repeated biochemical testing should be performed before DNA sequencing analysis. Our study suggests that 2% (95% confidence limits: 0.05–11.1%) of this Estonian XLMR panel are due to mutations in the SLC6A8, which is similar to the prevalence reported in other populations. We therefore conclude that creatine transporter deficiency is a relatively common genetic disorder in males with sporadic or familiar MR and diagnostic screening of them should always include screening for SLC6A8 deficiency.
Does parenting mediate the effects of exposure to violence on violent behavior? An ecological–transactional model of community violence
Authors: Spano Richard , Vazsonyi Alexander T. , Bolland John 
Published: January 2009

ABSTRACTThree waves of longitudinal data from a high poverty sample of 1544 African American youth were used to test an ecological–transactional model of violence. SEM analyses were conducted to determine whether parenting (Time 2) mediated the effects of exposure to violence (Time 1) on violent behaviors (Time 3). Findings supported the specified model. Multigroup SEM analyses indicated that neither family structure nor developmental stage (early versus middle/late adolescence) moderated these effects. However, exposure to violence had a larger effect on violent behaviors in female versus male youth, although the difference was simply in magnitude, not direction. A final model that predicted change scores also provided support for the hypothesized ecological–transactional model of violence.