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Selected AbstractsSquare-Wave Voltammetry as a Tool for Investigation of Doxorubicin Interactions with DNA Isolated from Neuroblastoma CellsELECTROANALYSIS, Issue 3-5 2009Dalibor Huska Abstract We investigated ethidium bromide intercalation into DNA molecule as a model system to test square-wave voltammetry (SWV) as a suitable method for this purpose We found that 0.13,,g EtBr intercalates into 1,,g dsDNA in average. Further, SWV was utilized for investigation of doxorubicin-DNA interactions. Intercalated doxorubicin reduced observed dsDNA cytosine and adenine (CA) signal, but also provided new signal called DOXO at ,0.35,V. This phenomenon was observed at both single and double stranded DNA standards. We also employed adsorptive transfer stripping technique coupled with SWV for study of doxorubicin-DNA interactions. Doxorubicin intercalation into dsDNA molecule adsorbed onto working electrode was fast, because we observed considerable changes in CA and DOXO signals after 360,s. Finally, we detected doxorubicin-DNA adducts formed in doxorubicin treated neuroblastoma cells. [source] Testing of the influenza virus purification by CIEFELECTROPHORESIS, Issue 2 2010Marie Horká Abstract In virological practice, the pre-concentration, purification and subsequent determination of the purity and concentration of the viruses from the cultural medium and/or from the real sample are required. The conventional techniques used today are equipment demanding, time-consuming and laborious. In this study, the CIEF of influenza viruses with UV detection has been developed and subsequently used to test the purification of the virus from the biological samples. The equine and swine influenza viruses present in infected allantoic fluid of specific pathogen free embryonated chicken eggs were precipitated by using PEG 6000 and sodium chloride. The precipitated viruses were centrifuged at 14,000×g, and the impurities of different densities were removed by using the sucrose gradients. The efficiency of the virus purification technique was examined by the CIEF and compared to the results of real-time PCR. The pIs of both influenza viruses were determined. Simultaneously, the CIEF was found to be a suitable method for the rapid testing of the efficiency of the virus purification. [source] Validation of techniques to detect illicit heroin use in patients prescribed pharmaceutical heroin for the management of opioid dependenceADDICTION, Issue 12 2005S. Paterson ABSTRACT Background The clinical implementation and evaluation of heroin substitution programmes have been confounded by the lack of objective and validated biomarkers for illicit heroin use in patients prescribed pharmaceutical heroin. This study examined the capacity to detect illicit heroin use by gas chromatography,mass spectrometry (GC-MS) analysis of urine samples for the presence of opium impurities common to illicit, but not pharmaceutical heroin. Aims To characterize the diagnostic properties of the metabolites of noscapine and papaverine in comparison to morphine as a gold-standard marker of illicit heroin use; and to examine the relationships between the self-reported time since most recent heroin use and the detection of these opioids in urine. Design A cross-sectional study of 52 opioid-dependent patients in treatment (not prescribed heroin), who self-reported illicit heroin use within the preceding 2 weeks. Self-report data regarding recent drug use and a urine sample were collected. GC-MS analyses of urines were conducted and reported by laboratory staff blinded to self-report data. Findings The metabolites of papaverine (hydroxypapaverine and dihydroxypapeverine) were found to have high sensitivity, specificity and negative predictive values as markers for illicit heroin use compared to the ,gold-standard' morphine. Other opioids, including 6-mono-acetylmorphine (6-MAM), codeine and noscapine metabolites (e.g. meconine) were less adequate in detecting heroin use. Conclusions GC-MS detection of papaverine metabolites in urine appears to be suitable method of identifying illicit heroin use for clinical and research purposes. [source] Immunological quantification of the nematode parasitic bacterium Pasteuria penetrans in soilFEMS MICROBIOLOGY ECOLOGY, Issue 3 2001S Fould Abstract Currently, the abundance of Pasteuria penetrans in soils, an unculturable bacterial parasite of root-knot nematodes (Meloidogyne spp.), is estimated by the percentage of nematode juveniles infected with bacteria and the number of spores attached to their cuticle. Indirect immunofluorescence led to detection of free spores directly in soil suspensions using UV light and polyclonal antibodies raised against two P. penetrans populations (ORS-21414-Sen and PP1). Three extraction methods were compared in order to improve spore recovery. A gentle shaking/sieving method recovered more than 90% of the spores inoculated in soils and was more efficient and simple than aqueous two-phase partitioning and polyethylene glycol extractions. All the spores inoculated in sandy or sandy,clay soils were detected with immunofluorescence microscopy. The quantification of the spores was improved using an ELISA technique that showed a good correlation between optical density and spore concentration in inoculated soils. Specific antibodies provide a suitable method to quantify P. penetrans and may be used to follow the evolution of the real pool of bacteria either in native suppressive soils or in inoculated ones. [source] Annual cycle and inter-annual variability of gross primary production and ecosystem respiration in a floodprone river during a 15-year periodFRESHWATER BIOLOGY, Issue 5 2006URS UEHLINGER Summary 1. Temporal variation in ecosystem metabolism over a 15-year period (1986,2000) was evaluated in a seventh order channelised gravel bed river (mean annual discharge 48.7 m3 s,1) of the Swiss Plateau. The river is subject to frequent disturbance by bed-moving spates. Daily integrals of gross primary production (GPP) and ecosystem respiration (ER) were calculated based on single-station diel oxygen curves. 2. Seasonal decomposition of the time series of monthly metabolism rates showed that approximately 50% of the variation of GPP and ER can be attributed to season. Annual GPP averaged 5.0 ± 0.6 g O2 m,2 day,1 and showed no long-term trend. 3. Ecosystem respiration, averaging 6.2 ± 1.4 g O2 m,2 day,1, declined from 8.8 to 4.1 g O2 m,2 day,1 during the 15-year period. This significant trend paralleled a decline in nitrate and soluble reactive phosphorus concentrations, and the biochemical oxygen demand discharged by sewage treatment facilities upstream of the study reach. The ratio of GPP to ER (P/R) increased from 0.53 to about 1 as consequence of ER reduction. 4. Bed moving spates reduced GPP by 49% and ER by 19%. Postspate recovery of GPP was rapid between spring and autumn and slow during winter. Recovery of ER lacked any seasonal pattern. Annual patterns of daily GPP and to a minor extent of daily ER can be described as a sequence of recovery periods frequently truncated by spates. 5. The study showed that disturbance by frequent bed-moving spates resulted in major stochastic variation in GPP and ER but annual patterns were still characterised by a distinct seasonal cycle. It also became evident that stream metabolism is a suitable method to assess effects of gradual changes in water quality. [source] Cover Picture: Fabrication of Stable Metallic Patterns Embedded in Poly(dimethylsiloxane) and Model Applications in Non-Planar Electronic and Lab-on-a-Chip Device Patterning (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 4 2005Mater. Abstract A composite image is shown that highlights examples of device architectures that either incorporate or exploit polymer-embedded metallic microstructures. In work reported by Nuzzo and co-workers on p.,557, new applications of soft lithography, in conjunction with advanced forms of multilayer metallization, are used to construct these exceptionally durable structures. They are suitable for use in non-planar lithographic patterning, and as device components finding applications ranging from microelectronics to Lab-on-a-Chip analytical systems. This article describes the fabrication of durable metallic patterns that are embedded in poly(dimethylsiloxane) (PDMS) and demonstrates their use in several representative applications. The method involves the transfer and subsequent embedding of micrometer-scale gold (and other thin-film material) patterns into PDMS via adhesion chemistries mediated by silane coupling agents. We demonstrate the process as a suitable method for patterning stable functional metallization structures on PDMS, ones with limiting feature sizes less than 5,,m, and their subsequent utilization as structures suitable for use in applications ranging from soft-lithographic patterning, non-planar electronics, and microfluidic (lab-on-a-chip, LOC) analytical systems. We demonstrate specifically that metal patterns embedded in both planar and spherically curved PDMS substrates can be used as compliant contact photomasks for conventional photolithographic processes. The non-planar photomask fabricated with this technique has the same surface shape as the substrate, and thus facilitates the registration of structures in multilevel devices. This quality was specifically tested in a model demonstration in which an array of one hundred metal oxide semiconductor field-effect transistor (MOSFET) devices was fabricated on a spherically curved Si single-crystalline lens. The most significant opportunities for the processes reported here, however, appear to reside in applications in analytical chemistry that exploit devices fabricated using the methods of soft lithography. Toward this end, we demonstrate durably bonded metal patterns on PDMS that are appropriate for use in microfluidic, microanalytical, and microelectromechanical systems. We describe a multilayer metal-electrode fabrication scheme (multilaminate metal,insulator,metal (MIM) structures that substantially enhance performance and stability) and use it to enable the construction of PDMS LOC devices using electrochemical detection. A polymer-based microelectrochemical analytical system, one incorporating an electrode array for cyclic voltammetry and a microfluidic system for the electrophoretic separation of dopamine and catechol with amperometric detection, is demonstrated. [source] In vitro testing to assess the UVA protection performance of sun care productsINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2001Applied Cosmetics) Task Force, Members of the DGK (German Society for Scientific, Sun Protection'. Synopsis The UVA protection delivered by sunscreens is an issue of increasing importance due to the increasing knowledge about UVA-induced skin damage. In Europe there is no officially accepted method available to determine the degree of UVA protection. Therefore, the objective of the present study was to design a protocol combining the merits of an in vitro model, which are simple and reproducible, with aspects known to be relevant from in vivo studies. The principle is: an UV-transparent support to which the test product is applied, a (pre)irradiation and a transmission measurement. Transpore® tape (standard support for SPF determinations) was found to be incompatible with many preparations on prolonged contact times. Roughened quartz was adopted as a suitable alternative. Transmission measurements on this support are not reliable with a layer of 2 mg cm,2 (standard for SPF) due to detection limitations of spectrophotometers, hence a reduced layer of 0.75 mg cm,2 was adopted. Overall, it is very difficult to apply products in a reproducible thin layer on appropriate substrates. As a consequence, absolute parameters derived from the transmission profile show relatively large dispersion, whereas relative parameters, such as critical wavelength ,c[1] or UVA/UVB ratio are much less sensitive to unavoidable variations in layer thickness. An increase in deviations was observed when the samples were irradiated before measurement. It is crucial to control the output carefully (spectral distribution and even more importantly, irradiance and dose delivered) of the light source. By doing so and also taking into account the previous learning steps, a protocol was drafted and tested in a ringtest (four samples in six laboratories). The results are encouraging and show that if relative parameters (e.g. ,c, UVA/UVB ratio) are considered, the intra- as well as interlaboratory reproducibility is clearly better than can be obtained in vivo. In general, we describe a suitable method, which can be considered in any future official discussions about the methodology to determine UVA protection. Résumé La protection contre les UVA apportée par les écrans solaires est un sujet d'importance croissante en raison de la progression des connaissances concernant les dommages à la peau causés par les UVA. En Europe il n'existe pas de méthode disponible officiellement reconnue pour déterminer le degré de protection contre les UVA. Par conséquent, l'objectif de la présente étude est de concevoir un protocole associant les avantages d'un modèle in vitro, qui est simple et reproductible, avec des aspects connus comme appartenant aux études in vivo. Le principe est le suivant: un support transparent aux UV auquel le produit testé est appliqué, une (pré)irradiation et une mesure de transmission. Le ruban Transpore® (support standard pour la détermination des SPF) se révèle incompatible avec de nombreuses préparations lors de temps de contact prolongés. Le quartz rugueux est adopté comme alternative appropriée. Les mesures de transmission sur ce support ne sont pas fiables avec une couche de 2 mg/cm2 (norme pour les SPF) en raison des limites de détection des spectrophotomètres, et on adopte donc une couche réduite de 0,75 mg/cm2. Il est surtout très difficile d'appliquer des produits en une couche fine reproductible sur des substrats appropriés. En conséquence, les paramètres absolus tirés du profil de transmission montrent une assez grande dispersion, tandis que les paramètres relatifs, tels que la longueur d'onde critique ,c[l] ou le rapport UVA/UVB sont beaucoup moins sensibles aux variations inévitables de l'épaisseur de la couche. On observe une augmentation des écarts lorsque les échantillons sont irradiés avant la mesure. Il est crucial de contrôler soigneusement la sortie (distribution spectrale et encore plus important, irradiation et dose délivrée) de la source lumineuse. Dans ces conditions, et en tenant aussi compte des enseignements des étapes précédentes, un protocole a étéébauché et testé lors d'un essai tournant (quatre échantillons dans six laboratoires). Les résultats sont encourageants et montrent que si on considère les paramètres relatifs (par exemple ,c, rapport UVA/UVB), la reproductibilité intra et interlaboratoires est clairement meilleures que ce qu'on peut obtenir in vivo. D'une façon générale, nous décrivons une méthode appropriée, qui peut être considérée dans tout échange officiel futur concernant la méthodologie pour déterminer la protection contre les UVA. [source] Alternative fuzzy operations and applications to social sciencesINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 12 2009Antonio Maturo Some humanistic systems find a suitable method of representation of their features in fuzzy numbers. This is due to the properties of fuzzy numbers that are used to describe indeterminateness. The applications of fuzzy numbers to Social Sciences request, in some cases, that the region of indeterminateness, called spreads, in the results of the operations between fuzzy numbers be less than the ones expected by Zadeh's extension principle. Furthermore, it is important to consider operations that save the shapes of fuzzy numbers for reasons of simplicity and clearness of modeling. To this aim, fuzzy operations are dealt with as possible alternatives to the operations induced by the extension principle. An application to Social Sciences is considered. Finally, the need for defining algebraic structures of fuzzy numbers (e.g., to extend to the fuzzy environment the de Finetti's concept of coherent prevision) leads to considerations for operations defined up to equivalence relations. Some fuzzy extensions of the coherent prevision are introduced. © 2009 Wiley Periodicals, Inc. [source] Evaluation of VIE and PIT tagging methods for juvenile cyprinid fishesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2009J. D. Bolland Summary Retention and mortality associated with visible implant elastomer (VIE) and passive integrated transponder (PIT) tagged juvenile chub [Leuciscus cephalus (L.)], dace [Leuciscus leuciscus (L.)] and roach [Rutilus rutilus (L.)] were evaluated. PIT tag retention (96.6,100%) was higher than VIE over the 6-month duration of the experiment. VIE retention was significantly better in the head (96.3,98.8%) than in the fins (78.8,90.9%) the first month after tagging, but the opposite was found after 6 months (head = 21.5,57.5%; fins = 77.2,88.8%). Survival was not significantly different from controls for any treatment, except dace tagged with 23-mm PIT (significantly influenced by mass of fish at tagging) and sham PIT tagged dace, because of initial losses. PIT tags are recommended as the most suitable method for tagging individual juvenile chub, dace and roach based on high retention and survival. VIE implantation in the head (studies < 30 days) and fins (studies > 30 days) could provide a cheap, batch-marking alternative, provided retention rates are monitored. [source] Using soft computing techniques for improving foot trajectories in walking machinesJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 7 2001Elena Garcia Walking machines have been investigated during the last 40 years and some basic techniques of this field are already well known. However, some aspects still need to be optimized. For instance, speed seems to be one of the major shortcomings of legged robots; thus, improving leg speed has been chosen as the main aim of this work. Although some algorithms for optimizing trajectory control of robot manipulators already exist, we propose a more computationally efficient method that employs fuzzy set theory to involve real dynamic effects over leg motion instead of an inaccurate mathematical model. In this article, we improve leg speed by automatically tuning the acceleration of legs. For this purpose, we define fuzzy rules based on experiments and we find the optimal acceleration for every given trajectory. A simple fuzzy inference system is used to compute the required acceleration. It is based on five rules using three linguistic variables. Final results show that foot acceleration tuning for straight trajectory generation is a suitable method for achieving accurate, smooth and fast foot movements. Also it is shown that under some conditions average leg speed can be increased up to 100% using the control methods herein proposed. © 2001 John Wiley & Sons, Inc. [source] A STUDY ON SUITABILITY OF FOUR ENRICHMENT BROTHS FOR PCR-BASED DETECTION OF LISTERIA MONOCYTOGENES FROM RAW MEATJOURNAL OF FOOD SAFETY, Issue 1 2006J. BALAMURUGAN ABSTRACT Four enrichment broths were evaluated for their compatibility with the polymerase chain reaction (PCR) for detection of Listeria monocytogenes from raw meat after single-step enrichment. Standardized PCR protocols for listeriolysin O (hlyA) gene were used for the species-specific identification of L. monocytogenes. Four broths, namely, modified University of Vermont broth (MUVM), Listeria enrichment broth (LEB), Fraser broth (FB) and polymyxin, acriflavin, lithium chloride, ceftazidime, aesculin, mannitol, egg yolk broth (PALCAM) , were inoculated with L. monocytogenes. The enriched cultures were subjected for PCR. Similarly, meat samples were artificially spiked with various concentrations of L. monocytogenes, these spiked samples were enriched in the above-mentioned four broths and subjected to PCR to determine the medium that was most compatible for PCR-based detection of L. monocytogenes. The aliquots taken during different incubation periods were subjected to three different procedures for the concentration of the target organism for use in PCR. Results revealed that MUVM was better than other broths for the detection of L. monocytogenes by both PCR and cultural method; moreover, it was able to support the growth of as low as 10 cfu/g of meat. Concentration of the target organisms by centrifugation and washing with PCR buffer was the most suitable method for improving PCR performance for detection of L. monocytogenes. Goat (n = 67) and buffalo (n = 45) meat samples from local markets were also screened by both PCR and cultural method to validate the results obtained from the spiking studies. Both results were in agreement in spiking studies as well as screening of market meat samples. [source] Stability of Lactobacillus reuteri in Different Types of MicrocapsulesJOURNAL OF FOOD SCIENCE, Issue 1 2006Parthiban Muthukumarasamy ABSTRACT: This study was designed to find the most suitable method and wall material for microencapsulation of the probiotic bacterium Lactobacillus reuteri to maintain cell viability during gastric challenge. Five L. reuteri strains were individually encapsulated using alginate, alginate plus starch, K-carrageenan with locust bean gum, or xanthan with gellan by extrusion or phase separation (emulsion). The morphology of the microcapsules was studied using phase contrast and cryo-scanning electron microscopy (cryo-SEM). The resistance of these microcapsules and the viability of contained L. reuteri to simulated gastric juice were studied. The shape and size of the microcapsules produced varied with the preparation method and type of wall material. Extruded microcapsules were larger and more uniformly shaped. Survival of microencapsulated L. reuteri was significantly better than that of planktonic cells and varied with the strain, method of microencapsulation, and wall material used. In general, microencapsulation using alginate and alginate with starch by both extrusion and phase separation were found to provide bacteria significantly greater protection (P < 0.05) against simulated gastric juice. [source] Age Determination of Ballpoint Pen Ink by Thermal Desorption and Gas Chromatography,Mass Spectrometry,JOURNAL OF FORENSIC SCIENCES, Issue 4 2008Jürgen H. Bügler Ph.D. Abstract:, Two main approaches can be used for determining the age of an ink: indirect dating and direct dating. Indirect dating is based on the chemical analysis of an ink followed by comparison with known samples in a reference collection. The collection should contain information about the inks including the market introduction dates. This approach may allow for an anachronism to be detected. The second concept is based on measuring ink components that change with age. The analysis of solvents in ballpoint inks may be a useful parameter for determining the age of ink on paper. In a previous study, the authors demonstrated that thermal desorption of ink directly from paper, followed by chemical analysis using gas chromatography,mass spectrometry (GC,MS), is a promising procedure for characterizing ink-binder resins and solvents. Preliminary tests showed that monitoring the evaporation of ink solvent from ink on paper is not a suitable method for ink dating. Thermal analysis of ink on paper in two steps revealed that fresh ink releases a relative amount of solvent at a certain low temperature in a defined period of time, which decreases as the ink ages. As a consequence, this relative amount of solvent released at a certain low temperature, and its decrease with time, can be used to estimate ink age. This age-dependent parameter was studied in 85 different inks ranging in age from 1 week to 1.5 years. It was found that some inks showed a significant decrease of this parameter up to an age of several months, and that the aging process can be monitored within this period. For other inks, however, the age-dependent parameter decreases relatively fast, e.g., within a few days, to a constant level, which can be too fast for casework. Based on these results, a general procedure for assessing the age of ballpoint pen inks on paper was developed. [source] Flow cytometry as a method for studying effects of stressors on primary rat neuronsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 3 2005H. Behbahani Abstract The mechanisms associated with cell death have been an important focus for neurobiology research. In the present study, the methodology of flow cytometry was used to optimize quantification of the toxic effects of tumor necrosis factor-, (TNF-,), trans-4-hydroxy-2-nonenal (4-HNE), and aged amyloid-, (A,1,42) on rat primary cortical neurons. The fluorescent dyes annexin V-FITC and propidium iodide (PI) were used to identify populations of viable, early apoptotic, necrotic and late apoptotic cells by flow cytometry. Prior to exposure, the primary cultures showed 83% cell viability. Flow cytometry following labeling of cells with a specific neuronal marker, TUJ-1, revealed 82% pure neuronal populations, whereas approximately 7% were astrocytic as shown by glial fibrillary acidic protein positivity. Exposure of primary cultures to TNF-,, 4-HNE, and aged A,1,42 gave an increased number of early apoptotic cells. We show that flow cytometry is a suitable method for quantifying effects of different stressors on neurons in primary cultures. This technique could be useful for screening and testing of pharmacological compounds relevant to neurodegenerative disorders. © 2005 Wiley-Liss, Inc. [source] ASSOCIATION OF STRAWBERRY YOGURT SENSORY PROPERTIES WITH PRODUCT COMPOSITION BY PROCRUSTES ANALYSISJOURNAL OF SENSORY STUDIES, Issue 4 2004ADRIANA GÁMBARO ABSTRACT The flavor of eight samples of commercial strawberry yogurt was studied by Free-Choice Profile analysis (FCP). Generalized Procrustes Analysis (GPA) applied to FCP allowed differentiation between samples and highlighted flavor attributes responsible for the observed differences. The relation between sensory and physicochemical datasets was studied by means of GPA. Those samples with higher carbohydrate content were perceived as sweeter, having stronger strawberry flavor, and with more dairy and yogurt flavors. Samples with higher titratable acidity, ash and protein content were perceived as more acidic and higher in intensity of "faulty" or "defective" flavors. Higher moisture content was associated with lower intensity of "dairy" flavors (creamy, dairy, and yogurt) and greater intensity of rancid flavor. It is concluded that, though not often used to this end, GPA is a suitable method to study the relationship of sensory and instrumental measurements. [source] Analysis of aldehydes via headspace SPME with on-fiber derivatization to their O -(2,3,4,5,6-pentafluorobenzyl)oxime derivatives and comprehensive 2D-GC-MSJOURNAL OF SEPARATION SCIENCE, JSS, Issue 19 2008Hans-Georg Schmarr Abstract A method for the analysis of the homologous series of alkanals, (E)-2-alkenals, and (E,E)-2,4-alkadienals is described utilizing a headspace solid-phase microextraction (HS-SPME) step and on-fiber derivatization with O -(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) hydrochloride. Oxime derivatives formed on the fiber are desorbed in the gas chromatographic injector and analyzed by comprehensive 2-D GC coupled to quadrupole MS (GC×GC-qMS). Selecting specific fragment ions within the electron impact mass spectra of the oxime derivatives provides a suitable method for the target analysis of these aldehyde classes, which furthermore benefits from the increased separation efficiency by GC×GC. The analysis of higher molecular weight aldehydes is described in wine and grape seed oil as examples. Quantification of the aldehydes utilizes a stable isotope dilution analysis (SIDA) assay with octan-d16 -al as isotopomeric internal standard. Besides the selectivity and sensitivity of aldehyde analysis using PFBHA derivatives, critical aspects on background level contamination and repeatability of the sample preparation method are discussed. Optimization of GC×GC-qMS parameters allowed a considerable saving of the cryogenic medium, involving additional (unmodulated) conditioning runs, rendering the method more amenable to routine analysis. [source] Dermoscopy is a suitable method for the observation of the pregnancy-related changes in melanocytic neviJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 8 2007AS Aktürk Summary Background, It is a common opinion that expansion and darkening in melanocytic nevi may occur during pregnancy. The main problem is that whether it is a usual finding, or it is a condition that requires suspicion about melanoma. Objectives, It was aimed to find the changes that might occur in the sizes and structures of melanocytic nevi during pregnancy. Methods, Ninety-seven nevi of the 56 pregnant women in the first trimester were evaluated in the study. The localization and size of the nevi were recorded on a standard body diagram. After clinical examination, dermoscopic analyses were applied. Pattern analyses were done, and total dermoscopy scores (TDS) were calculated by applying ABCD scoring system. All subjects were seen again during the third trimester. Results, There was a statistically significant difference between the mean diameters of nevi in the first and third trimester (P = 0.001). Of nevi whose diameters increased, 10 (50.00%) were localized on the front of body, 6 (30.00%) on the face and neck, 3 (15.00%) on the legs, and 1 (5.00%) on the back. The enlargement in diameters was more significant on the front of the body, but there was no statistically significant difference. Compared according to the pattern analysis, new dot formation was observed only on the structure of six nevi during the last trimester. Four of them were localized on the front of the body. There was statistically significant increase in mean TDS in comparison between the first and third trimesters (P = 0008). Conclusions, During the pregnancy, widening in diameters and structure changes of nevi may be seen especially on the front of the body. We also think that these findings might be connected with expansion of the skin during pregnancy. Dermoscopic controls are the first choice of method to analyse the nevi since the patient may not recognize these changes. [source] The MAGi RNA extraction method: a highly efficient and simple procedure for fresh and dry plant tissuesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2009e Gül Ince Abstract BACKGROUND: Samples from different plant species, different organs or tissues at different times of the year, usually show great differences in their cell compositions, pH, and the endogenous RNase activities, decreasing the RNA yield and quality. RESULTS: In this study we describe a reagent and a simple total RNA isolation method for plant organs, tissues and dry seeds. The RNA extraction reagent (MAGi) is non-toxic and can be stored at room temperature for several months to years. The principle of the total RNA extraction is that tissues are lysed in extraction solution with the aid of mortar homogenization,maceration, and cellular proteins, polysaccharides and DNA are removed from the RNA. We tested the reported method on more than 16 different types of plant seed and 15 different tissues and organs of pepper. CONCLUSION: The RNA extraction procedure reported in the present study greatly reduces the time required to isolate dry seed total RNA and other tissues by more than half as compared with the previously reported methods. The range of typical RNA yield and quality represents a significant improvement over existing protocols. The quality is high enough to be considered as suitable method for RT-PCR, cDNA library construction and microarray gene expression studies. Copyright © 2008 Society of Chemical Industry [source] Effect of lyophilisation, refrigerated storage and frozen storage on the coagulant activity and microbiological quality of Cynara cardunculus L. extractsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2008Luis Tejada Abstract BACKGROUND:Cheese-makers have traditionally kept vegetable coagulants refrigerated until use, even though little was known of their microbiological quality or coagulant activity during storage. This study aimed to assess the efficacy of lyophilisation, refrigerated storage and frozen storage of fresh vegetable extract as a means of standardising coagulant activity in terms of coagulation times, pH and microbiological quality. RESULTS:Neither the pH nor the coagulation time of lyophilised extracts was significantly modified during 1 year; however, changes were observed following frozen storage, and more notable following refrigerated storage. Lyophilisation of aqueous extracts prompted the destruction of most micro-organisms; low counts initially noted for total mesophiles, lactic acid bacteria and yeasts disappeared during the first few days of storage, due to low water activity. There was a generalised decrease in micro-organism counts during frozen storage. Refrigeration was found to be unsuitable for storing of cardoon extract; an increase of roughly 2 log unit counts was recorded in total mesophile, lactic acid bacteria, yeast and mould counts after 1 year of refrigerated storage. CONCLUSION:Refrigerated storage cannot be considered a suitable method for prolonged conservation of aqueous cardoon extract. Both lyophilisation and frozen storage of aqueous extracts proved ideal for prolonged storage of vegetable coagulant. Lyophilisation additionally had certain advantages over frozen storage. Copyright © 2008 Society of Chemical Industry [source] Preliminary study on the use of near-infrared reflectance spectroscopy to assess nitrogen content of undried wheat plantsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2007Alejandro Morón Abstract Near-infrared reflectance (NIR) spectroscopy combined with chemometrics was used to assess nitrogen (N) and dry matter content (DM) and chlorophyll in whole-wheat plant (Triticum aestivum L). Whole-wheat plant samples (n = 245) were analysed by reference method and by visible and NIR spectroscopy, in fresh (n = 182) and dry (n = 63) presentations, respectively. Calibration equations were developed using partial least squares (PLS) and validated using full cross-validation (leave-one-out method). Coefficient of determination in calibration (R2CAL) and the standard error of cross-validation (SECV) for N content in fresh sample presentation, after second derivative, were 0.89 (SECV: 0.64%), 0.86 (SECV: 0.66%) and 0.82 (SECV: 0.74%) using the visible + NIR, NIR and visible wavelength regions, respectively. Dry sample presentation gave better R2CAL and SECV for N compared with fresh presentation (R2CAL > 0.90, SECV < 0.20%) using visible + NIR. The results demonstrated that NIR is a suitable method to assess N concentration in wheat plant using fresh samples (unground and undried). Copyright © 2006 Society of Chemical Industry [source] Genotypic characterization of hospital Enterococcus faecalis strains using multiple-locus variable-number tandem-repeat analysisLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2009E. Wa, ecka Abstract Aims:, The level of genetic diversity and relationships between the specific genotypes and the distribution of virulence determinants among Enterococcus faecalis strains isolated from patients hospitalized in different wards of two hospitals were investigated. Methods and Results:, Fifty-six clinical strains of E. faecalis, isolated from patients hospitalized in the period of 1999,2004 in several wards in Wroc,aw (Poland), were analysed by multiple-locus variable-number tandem-repeat analysis (MLVA). Analysis of seven genomic loci identified 40 novel genotypes among the analysed E. faecalis strains, with two major genomic groups, designated I and II, distinguished at a cut-off of 35%. With a similarity cut-off of 85·7%, the genotypes could be combined into 12 clusters (C1,C12), containing at least two isolates. The remaining 18 MLVA types were represented by a single isolate. Conclusions:, Based on the data obtained by MLVA, it was found that (i) many E. faecalis isolates recovered from patients from the wards whose location allowed the potential transmission of micro-organisms, belonged to closely related MLVA types and (ii) possible relationships between specific E. faecalis genotype and the virulence factors lipase, haemolysin and esp gene can exist. Significance and Impact of the Study:, Our study confirms that MLVA is a suitable method for the epidemiological study of E. faecalis and for the first time shows possible relationships between specific genotypes and such virulence determinants, i.e. lipase, haemolysin and esp gene. [source] Study of the Cathode Potential in a Sputtering Discharge by Pulsing the Reactive Gas: Case of a W Target in an Ar-O2 AtmospherePLASMA PROCESSES AND POLYMERS, Issue 1 2007Nuno M.G. Parreira Abstract The process we used was d.c. magnetron sputtering, and we studied both the conventional process, using a constant flow of oxygen, and the process in which we pulsed the reactive gas. Square regulation signal with different pulsing periods (T) and oxygen injection time (ton) was used in the reactive gas pulsing (RGP), while the partial argon pressure was kept constant for all depositions. The oxygen flow rate during the injection time was sufficient to switch the process to compound sputtering mode, while the oxygen flow was stopped in the rest of period to allow cleaning of target. Sputtering experiments have shown that the instability phenomena, typical of the reactive sputtering process and known as the "hysteresis effect", are relatively weak due to the small reactivity of tungsten. The influence of the pulsing period and of the oxygen injection time on the deposition parameters is discussed in relation to the poisoning effect. It has been shown that d.c. magnetron sputtering with the oxygen pulsing is a suitable method to prepare tungsten oxide films. This process is very stable, leads to multilayered W-O coatings, and the deposition rates are slightly lower than those of obtained during the conventional process. [source] Synthesis of exfoliated polyamide 6,6/organically modified montmorillonite nanocomposites by in situ interfacial polymerizationPOLYMER COMPOSITES, Issue 6 2007M. Tarameshlou Polyamide 6,6 (PA 6,6)/organically modified montmorillonite (OMMT) nanocomposites were prepared by a novel method, using direct interfacial polymerization of an aqueous hexamethylene diamine and a nonaqueous adipoyl chloride in dichloromethane solution containing different amounts of OMMT dispersed nanoparticles. The state of dispersion of OMMT in the PA 6,6 matrix was investigated by means of X-ray diffraction, as well as transmission electronic microscopy. The results indicated that the OMMT nanoparticles were dispersed homogeneously and nearly exfoliated in the PA 6,6 matrix. The random arrangement of clay platelets in the PA 6,6 matrix, exfoliation, and intercalation of clays between the PA 6,6 matrix were distinguished. The amount of the incorporated OMMT in the PA 6,6 matrix was determined by means of TGA technique. Furthermore it was found that addition of a small amount of OMMT dramatically improved the thermal stability of PA 6,6. The TGA thermograms of all the synthesized nanocomposite samples showed an interesting unexpected lag in the weight loss at high temperatures, which could be another evidence for formation of fully exfoliated nanocomposites structures, with improved thermal stability. Nucleating effect of the OMMT nanoparticles and their influence on crystallization behavior of PA 6,6 was confirmed by DSC. Finally it is concluded that the in situ interfacial polycondensation is a suitable method for synthesis of nanocomposites with well dispersed structures and enhanced properties. POLYM. COMPOS., 28:733,738, 2007. © 2007 Society of Plastics Engineers [source] Large Scale Simulation with Scaled Boundary Finite Element MethodPROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2009Marco Schauer Nowadays scientific and engineering applications often require wave propagation in infinite or unbounded domains. In order to model such applications we separate our model into near-field and far-field. The near-field is represented by the well-known finite element method (FEM), whereas the far-field is mapped by a scaled boundary finite element (SBFE) approach. This latter approach allows wave propagation in infinite domains and suppresses the reflection of waves at the boundary, thus being a suitable method to model wave propagation to infinity. It is non-local in time and space. From a computational point of view, those characteristics are a drawback because they lead to storage consuming calculations with high computational time-effort. The non-locality in space causes fully populated unit-impulse acceleration influence matrices for each time step, leading to immense storage consumption for problems with a large number of degrees of freedom. Additionally, a different influence matrix has to be assembled for each time step which yields unacceptable storage requirements for long simulation times. For long slender domains, where many nodes are rather far from each other and where the influence of the degrees of freedom of those distant nodes is neglectable, substructuring represents an efficient method to reduce storage requirements and computational effort. The presented simulation with substructuring still yields satisfactory results. (© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Assessment of methods for the determination of digestibilities of feed ingredients for Tra catfish, Pangasinodon hypothalamusAQUACULTURE NUTRITION, Issue 4 2010T.T.T. HIEN Abstract In this study, we undertook a series of experiments to assess different faecal-collection methods and also the digestibilities of a range of feed ingredients when fed to Tra catfish (Pangasinodon hypothalamus). Apparent digestibility coefficients for dry matter, energy and nitrogen for a reference diet were also determined from faeces collected by way of settlement at 2-h intervals from 2 to 24 h. No significant effect of sample collection time on the digestibility values was observed. Stripping was attempted, but was not considered a suitable method for collecting digesta from Tra catfish. Dissection collection was also evaluated. Values determined from dissection collection were lower than those from using settlement. In a second experiment, a suite of test ingredients was combined with a reference diet component in a 30 : 70 ratio to determine the ingredients for dry matter, energy and nitrogen digestibilities. Ingredients included were trash-fish, defatted rice bran, wet full-fat rice bran, dried full-fat rice bran, broken rice, cassava, soybean and fish meals. Collection of faeces by settlement was used for determining the digestibility of each of the ingredients. The results showed that Tra catfish can efficiently digest protein and energy from a wide range of feed ingredients and nutrient sources. [source] Quantifying sponge erosions in Western Australian pearl oyster shellsAQUACULTURE RESEARCH, Issue 9 2010Sabine Daume Abstract This paper describes several methods to estimate the amount of sponge erosion in pearl oyster shells (Pinctada maxima Jameson, 1901). Internal erosion can be calculated from non-destructive surface area estimates because a clear relationship was found between the eroded area on the surface of the shells and internal erosions. Grading shells into three different categories, according to the severity of erosion, also proved to be a suitable method to quickly assess the amount of sponge erosions. All methods were more accurate in shells with larger amounts of erosions. Using the described methods, the Lacepedes fishing ground was more diverse in bioeroding sponge species compared with sites at the 80-Mile fishing ground locations. Pione velans Hentschel, 1909 was the dominant bioeroding sponge species but Cliona dissimilis Ridley and Dendy, 1886 eroded more shell material than P. velans. Observed patterns suggest that P. velans had a more recent recruitment than C. dissimilis. We suggest that visual grading together with estimates from the shell surface will be sufficient to determine the general long-term trends in bioeroding sponge severity. However, results of monitoring programmes need to be supplemented by histological examination to confirm sponge activity and species identity. [source] Geophysical prospection of the frontiers of the Roman Empire in southern Germany, UNESCO World Heritage SiteARCHAEOLOGICAL PROSPECTION, Issue 3 2010Jorg W. E. Fassbinder Abstract The Roman Limes with a length of 550,km is the largest archaeological site of Europe as well as the largest monument of the Roman period. In July 2005 it was decided that the Limes and its interrelated archaeological sites, together with Hadrian's Wall in England, would be a component of a ,Trans-National World Heritage Site' taking the name ,Frontiers of the Roman Empire'. From that point it was necessary to minimize and/or to avoid archaeological excavation. Further research on such sites is mainly limited to the application of non-destructive techniques. Among other geophysical tools, magnetometry, based on the rock magnetic knowledge turned out to be a highly suitable method. Two examples that allowed verification and completion of old maps of the Reichs-Limes-Kommission will be shown here; these projects exemplify geophysical work on the Bavarian Limes. At the site of Oberhochstatt we discovered the exact location and determined information on the size and orientation of the fort that previous searches for a long time had failed to find. At Theilenhofen we were able to complete the map of the whole fort with all fortification ditches and the water supply, to verify the troop level and to confirm the former fort on which is superimposed the traces of the Roman vicus. Copyright © 2010 John Wiley & Sons, Ltd. [source] Separation and quantification of inulin in selected artichoke (Cynara scolymus L.) cultivars and dandelion (Taraxacum officinale WEB. ex WIGG.) roots by high-performance anion exchange chromatography with pulsed amperometric detectionBIOMEDICAL CHROMATOGRAPHY, Issue 12 2006Katrin Schütz Abstract The profile of fructooligosaccharides and fructopolysaccharides in artichoke heads and dandelion roots was investigated. For this purpose, a suitable method for high-performance anion exchange chromatography with pulsed amperometic detection was developed. The separation of monomers, oligomers and polymers up to a chain length of 79 sugar residues was achieved in one single run. Glucose, fructose, sucrose and individual fructooligosaccharides (kestose, nystose, fructofuranosylnystose) were quantified in six different artichoke cultivars and in dandelion roots. The contents ranged from 12.9 g/kg DM to 71.7 g/kg DM for glucose, from 15.8 g/kg DM to 67.2 g/kg DM for fructose, and from 16.8 g/kg DM to 55.2 g/kg DM for sucrose in the artichoke heads. Kestose was the predominant fructooligosaccharide, followed by nystose and fructofuranosylnystose. In four cultivars fructofuranosylnystose was only detectable in traces and reached its maximum value of 3.6 g/kg DM in the cultivar Le Castel. Furthermore, an average degree of polymerization of 5.3 to 16.7 was calculated for the individual artichoke cultivars, which is noticeably lower than hitherto reported. In contrast, the contents of kestose, nystose and fructofuranosylnystose in dandelion root exceeded that of artichoke, reflecting the short chain characteristic of the inulin, which was confirmed by chromatographic analysis. Copyright © 2006 John Wiley & Sons, Ltd. [source] Dynamic Metabolic Modeling for a MAB BioprocessBIOTECHNOLOGY PROGRESS, Issue 1 2007Jianying Gao Production of monoclonal antibodies (MAb) for diagnostic or therapeutic applications has become an important task in the pharmaceutical industry. The efficiency of high-density reactor systems can be potentially increased by model-based design and control strategies. Therefore, a reliable kinetic model for cell metabolism is required. A systematic procedure based on metabolic modeling is used to model nutrient uptake and key product formation in a MAb bioprocess during both the growth and post-growth phases. The approach combines the key advantages of stoichiometric and kinetic models into a complete metabolic network while integrating the regulation and control of cellular activity. This modeling procedure can be easily applied to any cell line during both the cell growth and post-growth phases. Quadratic programming (QP) has been identified as a suitable method to solve the underdetermined constrained problem related to model parameter identification. The approach is illustrated for the case of murine hybridoma cells cultivated in stirred spinners. [source] Anal vector volume analysis complements endoanal ultrasonographic assessment of postpartum anal sphincter injuryBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 9 2000M. M. Fynes Background The aim of this study was to determine the role of anal vector manometry in the assessment of postpartum anal sphincter injury and to establish the most suitable method of anal vector volume analysis for identifying significant external anal sphincter (EAS) injury in an at-risk parous population. Methods A total of 101 consecutive women with a history of instrumental or traumatic vaginal delivery was recruited. Anal ultrasonography and anal vector manometry were performed. Receiver,operator characteristic curves were used to determine the usefulness of anal manometry and anal vector volume analysis in the identification of significant EAS disruption (full thickness, more than one quadrant involved) detected by ultrasonography. Results Seventeen women had significant EAS disruption identified by anal ultrasonography. Anal vector manometry provided complementary functional information. Anal vector symmetry index (VSI), determined by analysis of mean maximum squeeze pressure, yielded 100 per cent sensitivity for significant EAS disruption, with a positive predictive value of 61 per cent. Conclusion Anal vector manometry complements endoanal ultrasonography. VSI, determined by means of the squeeze pressure profile, correlates best with significant EAS disruption identified at anal ultrasonography. © 2000 British Journal of Surgery Society Ltd [source] | |||||||||||||||||||||||||