Home About us Contact
|
Home About us Contact | ||
|
|
||
Very Useful (very + useful)
Terms modified by Very Useful Selected AbstractsAnionic, in situ Generation of Formaldehyde: A Very Useful and Versatile Tool in Synthesis.CHEMINFORM, Issue 31 2007Geoffrey Deguest Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Time-Adaptive Lines for the Interactive Visualization of Unsteady Flow Data SetsCOMPUTER GRAPHICS FORUM, Issue 8 2009N. Cuntz I.3.3 [Computer Graphics]: Line and Curve Generation; I.3.1 [Computer Graphics]: Parallel Processing Abstract The quest for the ideal flow visualization reveals two major challenges: interactivity and accuracy. Interactivity stands for explorative capabilities and real-time control. Accuracy is a prerequisite for every professional visualization in order to provide a reliable base for analysis of a data set. Geometric flow visualization has a long tradition and comes in very different flavors. Among these, stream, path and streak lines are known to be very useful for both 2D and 3D flows. Despite their importance in practice, appropriate algorithms suited for contemporary hardware are rare. In particular, the adaptive construction of the different line types is not sufficiently studied. This study provides a profound representation and discussion of stream, path and streak lines. Two algorithms are proposed for efficiently and accurately generating these lines using modern graphics hardware. Each includes a scheme for adaptive time-stepping. The adaptivity for stream and path lines is achieved through a new processing idea we call ,selective transform feedback'. The adaptivity for streak lines combines adaptive time-stepping and a geometric refinement of the curve itself. Our visualization is applied, among others, to a data set representing a simulated typhoon. The storage as a set of 3D textures requires special attention. Both algorithms explicitly support this storage, as well as the use of precomputed adaptivity information. [source] Rapid and easy semi-quantitative evaluation method for diacylglycerol and inositol-1,4,5-trisphosphate generation in orexin receptor signallingACTA PHYSIOLOGICA, Issue 3 2010M. E. Ekholm Abstract Aim:, Fluorescent protein-based indicators have enabled measurement of intracellular signals previously nearly inaccessible for studies. However, indicators showing intracellular translocation upon response suffer from serious limitations, especially the very time-consuming data collection. We therefore set out in this study to evaluate whether fixing and counting cells showing translocation could mend this issue. Methods:, Altogether three different genetically encoded indicators for diacylglycerol and inositol-1,4,5-trisphosphate were transiently expressed in Chinese hamster ovary cells stably expressing human OX1 orexin receptors. Upon stimulation with orexin-A, the cells were fixed with six different protocols. Results:, Different protocols showed clear differences in their ability to preserve the indicator's localization (i.e. translocation after stimulus) and its fluorescence, and the best results for each indicator were obtained with a different protocol. The concentration,response data obtained with cell counting are mostly comparable to the real-time translocation and biochemical data. Conclusion:, The counting method, as used here, works at single time point and looses the single-cell-quantitative aspect. However, it also has some useful properties. First, it easily allows processing of a 100- to 1000-fold higher cell numbers than real-time imaging producing statistically consistent population-quantitative data much faster. Secondly, it does not require expensive real-time imaging equipment. Fluorescence in fixed cells can also be quantitated, though this analysis would be more time-consuming than cell counting. Thirdly, in addition to the quantitative data collection, the method could be applied for identifying responsive cells. This might be very useful in identification of e.g. orexin-responding neurones in a large population of non-responsive cells in primary cultures. [source] Four- and five-color flow cytometry analysis of leukocyte differentiation pathways in normal bone marrow: A reference document based on a systematic approach by the GTLLF and GEIL,,CYTOMETRY, Issue 1 2010Christine Arnoulet Abstract Background: The development of multiparameter flow cytometry (FCM) and increasingly sophisticated analysis software has considerably improved the exploration of hematological disorders. These tools have been widely applied in leukaemias, lymphomas, and myelodysplasias, yet with very heterogeneous approaches. Consequently, there is no extensive reference document reporting on the characteristics of normal human bone marrow (BM) in multiparameter FCM. Here, we report a reference analysis procedure using relevant antibody combinations in normal human BM. Methods: A first panel of 23 antibodies, constructed after literature review, was tested in four-color combinations (including CD45 in each) on 30 samples of BM. After evaluation of the data, a second set of 22 antibodies was further applied to another 35 BM samples. All list-modes from the 65 bone marrow samples were reviewed collectively. A systematised protocol for data analysis was established including biparametric representations and color codes for the three major lineages and undifferentiated cells. Results: This strategy has allowed to obtain a reference atlas of relevant patterns of differentiation antigens expression in normal human BM that is available within the European LeukemiaNet. This manuscript describes how this atlas was constructed. Conclusions: Both the strategy and atlas could prove very useful as a reference of normality, for the determination of leukemia-associated immunophenotypic patterns, analysis of myelodysplasia and, ultimately, investigation of minimal residual disease in the BM. © 2009 Clinical Cytometry Society [source] Neurophysiologic evaluation of early cognitive development in high-risk infants and toddlersDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 4 2005Raye-Ann deRegnier Abstract New knowledge of the perceptual, discriminative, and memory capabilities of very young infants has opened the door to further evaluation of these abilities in infants who have risk factors for cognitive impairments. A neurophysiologic technique that has been very useful in this regard is the recording of event-related potentials (ERPs). The event-related potential (ERP) technique is widely used by cognitive neuroscientists to study cognitive abilities such as discrimination, attention, and memory. This method has many attractive attributes for use in infants and children as it is relatively inexpensive, does not require sedation, has excellent temporal resolution, and can be used to evaluate early cognitive development in preverbal infants with limited behavioral repertories. In healthy infants and children, ERPs have been used to gain a further understanding of early cognitive development and the effect of experience on brain function. Recently, ERPs have been used to elucidate atypical memory development in infants of diabetic mothers, difficulties with perception and discrimination of speech sounds in infants at risk for dyslexia, and multiple areas of cognitive differences in extremely premature infants. Atypical findings seen in high-risk infants have correlated with later cognitive outcomes, but the sensitivity and specificity of the technique has not been studied, and thus evaluation of individual infants is not possible at this time. With further research, this technique may be very useful in identifying children with cognitive deficits during infancy. Because even young infants can be examined with ERPs, this technique is likely to be helpful in the development of focused early intervention programs used to improve cognitive function in high-risk infants and toddlers. © 2005 Wiley-Liss, Inc. MRDD Research Reviews 2005;11:317,324. [source] Gene targeted ablation of high molecular weight fibroblast growth factor-2DEVELOPMENTAL DYNAMICS, Issue 2 2009Mohamad Azhar Abstract Fibroblast growth factor-2 (FGF2) is produced as high molecular weight isoforms (HMW) and a low molecular weight isoform (LMW) by means of alternative usage of translation start sites in a single Fgf2 mRNA. Although the physiological function of FGF2 and FGF2 LMW has been investigated in myocardial capillarogenesis during normal cardiac growth, the role of FGF2 HMW has not been determined. Here, we report the generation of FGF2 HMW-deficient mice in which FGF2 HMW isoforms are ablated by the Tag-and-Exchange gene targeting technique. These mice are normal and fertile with normal fecundity, and have a normal life span. Histological, immunohistochemical, and morphometric analyses indicate normal myocardial architecture, blood vessel, and cardiac capillary density in young adult FGF2 HMW-deficient mice. These mice along with the FGF2- and FGF2 LMW-deficient mice that we have generated previously will be very useful for elucidating the differential functions of FGF2 isoforms in pathophysiology of cardiovascular diseases. Developmental Dynamics 238:351,357, 2009. © 2008 Wiley-Liss, Inc. [source] Enhancer detection in the ascidian Ciona intestinalis with transposase-expressing lines of MinosDEVELOPMENTAL DYNAMICS, Issue 1 2008Yasunori Sasakura Abstract Germline transgenesis with a Tc1/mariner superfamily Minos transposon was achieved in the ascidian Ciona intestinalis. Transgenic lines that express transposases in germ cells are very useful for remobilizing transposon copies. In the present study, we created transposase-expressing lines of Minos in Ciona. A Ciona gene encoding protamine (Ci - prm) is expressed in the testes and sperm. Transgenic lines expressing Minos transposase in the testes and sperm were created with a cis -element of Ci - prm, and used for enhancer detection. Double-transgenic animals between transposase lines and a transgenic line with an enhancer detection vector passed on several independent enhancer detection events to subsequent progeny. This technique allowed us to isolate transgenic lines that express GFP in restricted tissues. This system provides an easy and efficient method for large-scale enhancer detection in Ciona intestinalis. Developmental Dynamics 237:39,50, 2008. © 2007 Wiley-Liss, Inc. [source] Development and topography of the lateral olfactory tract in the mouse: Imaging by genetically encoded and injected fluorescent markersDEVELOPMENTAL NEUROBIOLOGY, Issue 8 2006Andreas Walz Abstract In mammals, conventional odorants are detected by OSNs located in the main olfactory epithelium of the nose. These neurons project their axons to glomeruli, which are specialized structures of neuropil in the olfactory bulb. Within glomeruli, axons synapse onto dendrites of projection neurons, the mitral and tufted (M/T) cells. Genetic approaches to visualize axons of OSNs expressing a given odorant receptor have proven very useful in elucidating the organization of these projections to the olfactory bulb. Much less is known about the development and connectivity of the lateral olfactory tract (LOT), which is formed by axons of M/T cells connecting the olfactory bulb to central neural regions. Here, we have extended our genetic approach to mark M/T cells of the main olfactory bulb and their axons in the mouse, by targeted insertion of IRES-tauGFP in the neurotensin locus. In NT-GFP mice, we find that M/T cells of the main olfactory bulb mature and project axons as early as embryonic day 11.5. Final innervation of central areas is accomplished before the end of the second postnatal week. M/T cell axons that originate from small defined areas within the main olfactory bulb, as visualized by localized injections of fluorescent tracers in wild-type mice at postnatal days 1 to 3, follow a dual trajectory: a branch of tightly packed axons along the dorsal aspect of the LOT, and a more diffuse branch along the ventral aspect. The dorsal, but not the ventral, subdivision of the LOT exhibits a topographical segregation of axons coming from the dorsal versus ventral main olfactory bulb. The NT-GFP mouse strain should prove useful in further studies of development and topography of the LOT, from E11.5 until 2 weeks after birth. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source] PEUTZ,JEGHERS POLYPOSIS WITH BLEEDING FROM POLYPS OF THE SIGMOID COLON SUCCESSFULLY TREATED BY LAPAROSCOPIC SURGERYDIGESTIVE ENDOSCOPY, Issue 1 2003Kazuhiro Yada We report a case of colonic bleeding complicating congestive heart failure in a patient with Peutz,Jeghers (P,J) polyposis successfully treated by laparoscopic surgery. A 49-year-old woman was admitted for severe cough and edema of the extremities. Chest X-ray revealed bilateral pleural effusion and cardiomegaly. Her cardiac function was within normal limits, but anemia and severe hypoproteinemia were observed. During the treatment, anal bleeding was observed. Endoscopic and radiographic examinations revealed hundreds of polyps from the duodenum to the rectum. 99mTc-diethylene triamine penta-acetic acid human serum albumin scintigraphy showed radiotracer collected in the sigmoid colon, the area having the most polyps. After some intestinal polypoid lesions were resected endoscopically, laparoscopy-assisted sigmoid colectomy and cecectomy were performed. In the postoperative course, she complained less about abdominal pain and her first flatus occurred on the third postoperative day. She recovered uneventfully. The anemia, hypoproteinemia, and congestive heart failure resolved and gastrointestinal bleeding has not been seen. It was thought that protein loss and hemorrhage due to the P,J polyposis caused congestive heart failure. When congestive heart failure is accompanied by gastrointestinal hemorrhage, it is important to consider hypoproteinemia due to gastrointestinal polyposis, such as that characterizing P,J syndrome. Laparoscopic surgery was very useful for the treatment of colonic bleeding. [source] Seismic response analysis on the stability of running vehiclesEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 11 2002Yoshihisa Maruyama Abstract The seismometer network of the Japanese expressway system has been enhanced since the 1995 Kobe earthquake. Using earthquake information from the instruments, the expressways are closed if the peak ground acceleration (PGA) is larger than or equal to 80cm/s2. The aim of this regulation is to avoid secondary disasters, e.g. cars running into the collapsed sections. However, recent studies on earthquake damage have revealed that expressway structures are not seriously damaged under such-level of earthquake motion. Hence, we may think of relaxing the regulation of expressway closure. But before doing this, it is necessary to examine the effects of shaking to automobiles since the drivers may encounter difficulties in controlling their vehicles and traffic accidents may occur. In this study, a vehicle was modelled with a six-degree-of-freedom system and its responses were investigated with respect to PGA, peak ground velocity (PGV) and Japan Meteorological Agency (JMA) seismic intensity using five ground motion records. It was observed that the response of the vehicle shows a larger amplitude for the record that has larger response spectrum in the long period range compared to other records. However, similar response amplitudes of the vehicle were observed for all the records with respect to the JMA seismic intensity. The response characteristics of the vehicle model may be very useful for decision-making regarding the relaxation of the expressway closure under seismic motion. Copyright © 2002 John Wiley & Sons, Ltd. [source] Aspergillus niger Aortitis after Aortic Valve Replacement Diagnosed by Transesophageal EchocardiographyECHOCARDIOGRAPHY, Issue 5 2006Hamza Duygu M.D. Aspergillus aortitis following cardiac surgery has an important role among the cardiac infections as almost all affected cases result in death. Survival of the patient with Aspergillus aortitis is dependent on early initiation of aggressive medical and surgical treatment. Transesophageal echocardiography proved very useful in the diagnosis of this uncommon case of aortitis. In this paper, we present a patient with aortitis caused by Aspergillus niger that hasn't been reported previously diagnosed by transesophageal echocardiography following cardiac surgery. [source] A Web page that provides map-based interfaces for VRML/X3D contentELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 2 2009Yoshihiro Miyake Abstract The electronic map is very useful for navigation in the VRML/X3D virtual environments. So far various map-based interfaces have been developed. But they are lacking for generality because they have been separately developed for individual VRML/X3D contents, and users must use different interfaces for different contents. Therefore, we have developed a Web page that provides a common map-based interface for VRML/X3D contents on the Web. Users access VRML/X3D contents via the Web page. The Web page automatically generates a simplified map by analyzing the scene graph of downloaded contents, and embeds the mechanism to link the virtual world and the map. An avatar is automatically created and added to the map, and both a user and its avatar are bidirectionally linked together. In the simplified map, obstructive objects are removed and the other objects are replaced by base boxes. This paper proposes the architecture of the Web page and the method to generate simplified maps. Finally, an experimental system is developed in order to show the improvement of frame rates by simplifying the map. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 92(2): 28,37, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10017 [source] Simultaneous detection of genetically modified organisms by multiplex ligation-dependent genome amplification and capillary gel electrophoresis with laser-induced fluorescenceELECTROPHORESIS, Issue 13 2010Virginia García-Cañas Abstract In this work, an innovative method useful to simultaneously analyze multiple genetically modified organisms is described. The developed method consists in the combination of multiplex ligation-dependent genome dependent amplification (MLGA) with CGE and LIF detection using bare-fused silica capillaries. The MLGA process is based on oligonucleotide constructs, formed by a universal sequence (vector) and long specific oligonucleotides (selectors) that facilitate the circularization of specific DNA target regions. Subsequently, the circularized target sequences are simultaneously amplified with the same couple of primers and analyzed by CGE-LIF using a bare-fused silica capillary and a run electrolyte containing 2-hydroxyethyl cellulose acting as both sieving matrix and dynamic capillary coating. CGE-LIF is shown to be very useful and informative for optimizing MLGA parameters such as annealing temperature, number of ligation cycles, and selector probes concentration. We demonstrate the specificity of the method in detecting the presence of transgenic DNA in certified reference and raw commercial samples. The method developed is sensitive and allows the simultaneous detection in a single run of percentages of transgenic maize as low as 1% of GA21, 1% of MON863, and 1% of MON810 in maize samples with signal-to-noise ratios for the corresponding DNA peaks of 15, 12, and 26, respectively. These results demonstrate, to our knowledge for the first time, the great possibilities of MLGA techniques for genetically modified organisms analysis. [source] Optimal separation times for electrical field flow fractionation with Couette flowsELECTROPHORESIS, Issue 20 2008Jennifer Pascal Abstract The prediction of optimal times of separation as a function of the applied electrical field and cation valence have been studied for the case of field flow fractionation [Martin M., Giddings J. C., J. Phys. Chem. 1981, 85, 727] with charged solutes. These predictions can be very useful to a priori design or identify optimal operating conditions for a Couette-based device for field flow fractionation when the orthogonal field is an electrical field. Mathematically friendly relationships are obtained by applying the method of spatial averaging to the solute species continuity equation; this is accomplished after the role of the capillary geometrical dimensions on the applied electrical field equations has been assessed [Oyanader M. A., Arce P., Electrophoresis 2005; 26, 2857]. Moreover, explicit analytical expressions are derived for the effective parameters, i.e. diffusivity and convective velocity as functions of the applied (orthogonal) electrical field. These effective transport parameters are used to study the effect of the cation valence of the solutes and of the magnitude of the applied orthogonal electrical field on the values of the optimal time of separation. These parameters play a significant role in controlling the optimal separation time, leading to a family of minimum values, for particular magnitudes of the applied orthogonal electrical field. [source] Analysis of plasma protein adsorption onto PEGylated nanoparticles by complementary methods: 2-DE, CE and Protein Lab-on-chip® systemELECTROPHORESIS, Issue 13 2007Hyun Ryoung Kim Abstract The biodistribution of colloidal carriers after their administration in vivo depends on the adsorption of some plasma proteins and apolipoproteins on their surface. Poly(methoxypolyethyleneglycol cyanoacrylate- co -hexadecylcyanoacrylate) (PEG-PHDCA) nanoparticles have demonstrated their capacity to cross the blood,brain barrier (BBB) by a mechanism of endocytosis. In order to clarify this mechanism at the molecular level, proteins and especially apolipoproteins adsorbed at the surface of PEG-PHDCA nanoparticles were analyzed by complementary methods such as CE and Protein Lab-on-chip® in comparison with 2-D PAGE as a method of reference. Thus, the ability of those methodologies to identify and quantify human and rat plasma protein adsorption onto PEG-PHDCA nanoparticles and conventional PHDCA nanoparticles was evaluated. The lower adsorption of proteins onto PEG-PHDCA nanoparticles comparatively to PHDCA nanoparticles was evidenced by 2-D PAGE and Protein Lab-on-chip® methods. CE allowed the quantification of adsorbed proteins without the requirement of a desorption procedure but failed, in this context, to analyze complex mixtures of proteins. The Protein Lab-on-chip® method appeared to be very useful to follow the kinetic of protein adsorption from serum onto nanoparticles; it was complementary to 2-D PAGE which allowed the identification (with a relative quantification) of the adsorbed proteins. The overall results suggest the implication of the apolipoprotein E in the mechanism of passage of PEG-PHDCA nanoparticles through the BBB. [source] Sensitive and simultaneous analysis of five transgenic maizes using multiplex polymerase chain reaction, capillary gel electrophoresis, and laser-induced fluorescenceELECTROPHORESIS, Issue 14 2004Virginia García-Cañas Abstract The benefits of using multiplex polymerase chain reaction (PCR) followed by capillary gel electrophoresis with laser-induced fluorescence (CGE-LIF) for the simultaneous detection of five transgenic maizes (Bt11, T25, MON810, GA21, and Bt176) are demonstrated. The method uses a hexaplex PCR protocol to amplify the five mentioned transgenic amplicons plus the zein gene used as reference, followed by a CGE-LIF method to analyze the six DNA fragments. CGE-LIF was demonstrated very useful and informative for optimizing multiplex PCR parameters such as time extension, PCR buffer concentration and primers concentration. The method developed is highly sensitive and allows the simultaneous detection in a single run of percentages of transgenic maize as low as 0.054% of Bt11, 0.057% of T25, 0.036% of MON810, 0.064% of GA21, and 0.018% of Bt176 in flour obtaining signals still far from the detection limit (namely, the signal/noise ratios for the corresponding DNA peaks were 41, 124, 98, 250, 252, and 473, respectively). These percentages are well below the minimum threshold marked by the European Regulation for transgenic food labeling (i.e., 0.5,0.9%). A study on the reproducibility of the multiplex PCR-CGE-LIF procedure was also performed. Thus, values of RSD lower than 0.67 and 6.80% were obtained for migration times and corrected peak areas, respectively, for the same sample and three different days (n = 12). On the other hand, the reproducibility of the whole procedure, including four different multiplex PCR amplifications, was determined to be better than 0.66 and 23.3% for migration times and corrected peak areas, respectively. Agarose gel electrophoresis (AGE) and CGE-LIF were compared in terms of resolution and sensitivity for detecting PCR products, demonstrating that CGE-LIF can solve false positives induced by artifacts from the multiplex PCR reaction that could not be addressed by AGE. Moreover, CGE-LIF provides better resolution and sensitivity. To our knowledge, these results demonstrate for the first time that multiplex PCR-CGE-LIF is a solid alternative to determine multiple genetically modified organisms in maize flours in a single run. [source] Proteomics of snake venoms from Elapidae and Viperidae families by multidimensional chromatographic methodsELECTROPHORESIS, Issue 16 2003Jiraporn Nawarak Abstract Snake venoms contain a large number of biologically active substances and the venom components are very useful for pharmaceutical applications. Our goal is to separate and identify components of snake venoms in ten snake species from the Elapidae and Viperidae families using multidimensional chromatographic methods. The multidimensional chromatographic methods include reversed-phase high-performance liquid chromatography (RP-HPLC), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), lab-on-a-chip, two-dimensional electrophoresis (2-DE), and mass spectrometry. The venoms of eight snake species demonstrated major differences in hydrophobicity, molecular weight separations, and 2-DE protein distribution patterns. The 2-DE images showed major differences between families, within each family and even between the same species. Venoms of the Elapidae family showed many basic proteins with a wide range of molecular weights, while venoms of the Viperidae family showed wide ranges of pI and molecular weights, especially for Trimeresurus sp. The multidimensional chromatographic methods revealed specific differences in venom proteins intra-species as well as between species and families. We have isolated and identified proteins that may be unique for each species for further studies in the proteome of snake venoms and their potentially use in the pharmaceutical applications. [source] Potentialities of quantile regression to predict ozone concentrationsENVIRONMETRICS, Issue 2 2009S. I. V. Sousa Abstract This paper aims: (i) to analyse the influence of ozone precursors (both meteorological variables and pollutant concentrations) on ozone concentrations at different ozone levels; and (ii) to predict next day hourly ozone concentrations using a new approach based on quantile regression (QR). The performance of this model was compared with multiple linear regressions (MLR) for the three following periods: daylight, night time and all day. QR as proven to be an useful mathematical tool to evidence the heterogeneity of ozone predictor influences at different ozone levels. Such heterogeneity is generally hidden when an ordinary least square regression model is applied. The influence of previous concentrations of ozone and nitrogen monoxide on next day ozone concentrations was higher for lower quantiles. When QR was applied, the wind direction (WD) was found to be significant in the medium quantiles and the relative humidity (RH) in the higher quantiles. On the contrary, using the MLR models, both variables were not statistically significant. Moreover, QR allowed more efficient previsions of extreme values which are very useful once the forecasting of higher concentrations is fundamental to develop strategies for protecting the public health. Copyright © 2008 John Wiley & Sons, Ltd. [source] Estimating within-field variation using a nonparametric density algorithmENVIRONMETRICS, Issue 5 2006A. Castrignanò Abstract The application of site-specific techniques and technologies in precision farming requires subdividing a field into a generally small number of contiguous homogeneous zones. The proposed algorithm of clustering is based on nonparametric density estimate, where a cluster is defined as a region surrounding a local maximum of the probability density function. Soil samples were collected in a 2-ha field of the experimental farm of the Agricultural Research Institute, located in Foggia (Southern Italy) and some of the most production-affecting soil properties were interpolated by using the geostatistical techniques of kriging and cokriging. The application of the clustering approach to the (co)kriged surface variables produced the subdivision of the field into five distinct classes. The proposed algorithm proves quite promising in identifying spatially contiguous zones, which are more homogeneous in soil properties than the whole-field. Its great advantage consists in giving an additional description of the residual variation within the class and such a piece of information is very useful in precision farming as a basis for the variable-rate application of agronomic inputs. Copyright © 2005 John Wiley & Sons, Ltd. [source] Photophysical and Photochemical Properties of Fluorinated and Nonfluorinated n -Propanol-Substituted Zinc PhthalocyaninesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2010lke Gürol Abstract The synthesis of symmetrical fluorinated and nonfluorinated zinc(II) phthalocyanine derivatives obtained from 4,5-dichlorophthalonitrile, 4-nitrophthalonitrile and 3-nitrophthalonitrile substituted with 2,2,3,3-tetrafluoro-1-propanol and n -propanol are described. The comparison of the photophysicochemical properties of fluorinated and nonfluorinated substituted zinc(II) phthalocyanines is reported for the first time. The new compounds have been characterized by elemental analysis, IR, 1H NMR and 19F NMR spectroscopy, electronic spectroscopy and mass spectra. The photophysical and photochemical properties of the compounds were studied in dimethyl sulfoxide (DMSO). The complexes were quenched with benzoquinone (BQ), and their fluorescence-quenching properties were investigated in the same solvent. The effects of the number of the substitution and the position on the photophysical and photochemical parameters of the zinc(II) phthalocyanines 1a,7a are also reported. Photophysical and photochemical properties of phthalocyanine complexes are very useful for photodynamic therapy (PDT) of cancer applications. In particular, high singlet-oxygen quantum yields are very important for Type II mechanisms. These complexes have good singlet-oxygen quantum yields and show potential as Type-II photosensitizers. [source] EFNS guideline on neuroimaging in acute stroke.EUROPEAN JOURNAL OF NEUROLOGY, Issue 12 2006Report of an EFNS task force Neuroimaging techniques are necessary for the evaluation of stroke, one of the leading causes of death and neurological impairment in developed countries. The multiplicity of techniques available has increased the complexity of decision making for physicians. We performed a comprehensive review of the literature in English for the period 1965,2005 and critically assessed the relevant publications. The members of the panel reviewed and corrected an initial draft, until a consensus was reached on recommendations stratified according to the European Federation of Neurological Societies (EFNS) criteria. Non-contrast computed tomography (CT) scan is the established imaging procedure for the initial evaluation of stroke patients. However, magnetic resonance imaging (MRI) has a higher sensitivity than CT for the demonstration of infarcted or ischemic areas and depicts well acute and chronic intracerebral hemorrhage. Perfusion and diffusion MRI together with MR angiography (MRA) are very helpful for the acute evaluation of patients with ischemic stroke. MRI and MRA are the recommended techniques for screening cerebral aneurysms and for the diagnosis of cerebral venous thrombosis and arterial dissection. For the non-invasive study of extracranial vessels, MRA is less portable and more expensive than ultrasonography but it has higher sensitivity and specificity for carotid stenosis. Transcranial Doppler is very useful for monitoring arterial reperfusion after thrombolysis, for the diagnosis of intracranial stenosis and of right-to-left shunts, and for monitoring vasospasm after subarachnoid hemorrhage. Currently, single photon emission computed tomography and positron emission tomography have a more limited role in the evaluation of the acute stroke patient. [source] Global Techniques for Characterizing Phase Transformations , A Tutorial ReviewADVANCED ENGINEERING MATERIALS, Issue 6 2010Michel Perez To characterize phase transformations, it is necessary to get both local and global information. No experimental technique alone is capable of providing these two types of information. Local techniques are very useful to get information on morphology and chemistry but fail to deal with global information like phase fraction and size distribution since the analyzed volume is very limited. This is why, it is important to use, in parallel, global experimental techniques, that investigate the response of the whole sample to a stimulus (electrical, thermal, mechanical,). The aim of this paper is not to give an exhaustive list of all global experimental techniques, but to focus on a few examples of recent studies dealing with the characterization of phase transformations, namely (i) the measurement of the solubility limit of copper in iron, (ii) the tempering of martensite, (iii) the control of the crystallinity degree of a ultra high molecular weight polyethylene and (iii) a precipitation sequence in aluminum alloys. Along these examples, it will be emphasized that any global technique requires a calibration stage and some modeling to connect the measured signal with the investigated information. [source] Imaging of Cell-to-Material Interfaces by SEM after in situ Focused Ion Beam Milling on Flat Surfaces and Complex 3D-Fibrous Structures,ADVANCED ENGINEERING MATERIALS, Issue 11 2009Anne Greet Bittermann Detailed analysis of the cell-to-implant interface needs to be performed prior to medical application. As these interfaces are often not accessible for direct visualization SEM after in situ focused ion beam milling was explored that allows selecting the regions of interest and serial sectioning for analysis of large scale implant architecture/topology down to detailed sub-cellular structures in one sample that might be very useful for (bio)material characterization. [source] The 15N-CPMAS spectra of simazine and its metabolites: measurements and quantum chemical calculationsEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2007A. E. Berns Summary DFT calculations are a powerful tool to support NMR studies of xenobiotics such as decomposition studies in soil. They can help interpret spectra of bound residues, for example, by predicting shifts for possible model bonds. The described bound-residue models supported the hypothesis of a free amino side chain already suspected by comparison with the experimental data of the standards. No match was found between the calculated shifts of amide bondings of the amino side chains (free or substituted) and the experimental NMR shifts of a previous study. In the present paper, first-principles quantum chemical calculations were used to support and check the interpretation of the 15N cross polarization-magic angle spinning nuclear magnetic resonance (15N-CPMAS NMR) spectra of simazine and its metabolites. Density functional theory (DFT) calculations were performed using Gaussian 03 and the nuclear magnetic shielding tensors were calculated using the Gauge-Independent Atomic Orbital (GIAO) method and B3LYP/6,311+G(2d,p) model chemistry. Good agreement was reached between the calculated and measured chemical shifts of the core nitrogens and the lactam and lactim forms of the hydroxylated metabolites could be clearly distinguished. The calculated spectra showed that these metabolites exist preferentially in the lactam form, an important fact when considering the possible interactions of such hydroxylated metabolites with the soil matrix. Although the calculated bound-residue models in the present study only partly matched the experimental data, they were nevertheless useful in helping to interpret the experimental NMR results of a previous study. To get a better match between the calculated and the measured shifts of the side-chain nitrogens the calculations need to be further developed, taking into account the influence of neighbouring molecules in the solid state. Altogether, quantum chemical calculations are very helpful in the interpretation of NMR spectra. In the future, they can also be very useful for the prediction of NMR shifts, in particular when it is not possible to measure the metabolites due to a lack of material or in cases where practical experiments cannot be conducted. [source] Determination of Activation Volume in Nanocrystalline Cu Using the Shear Punch Test,ADVANCED ENGINEERING MATERIALS, Issue 10 2007K. Guduru Stress relaxation test (SRT) is very useful to study the dislocation dynamics and thus the deformation behavior. It becomes quite difficult to use conventional testing methods when the material availability is limited. In such instances, miniaturized specimen testing procedures such as shear punch test (SPT) becomes significantly useful for studying the mechanical behavior of materials. Current research deals with a novel SRT method employed on nanocrystalline Cu using SPT to study the deformation mechanism. [source] Strategy to assess the efficiency of U1 RNA-hammerhead ribozyme constructs using GFP-tagged targetsEXPERIMENTAL DERMATOLOGY, Issue 5 2003Peter B. Cserhalmi-Friedman Abstract: The application of ribozymes for gene therapy of autosomal dominant diseases has become popularized in recent years. Further this technology has widespread utility in the treatment of any disease, acquired or inherited, by inhibition of gene expression. The design of ribozymes is usually accomplished using computer assisted design programs, however they are not very useful in predicting the behavior of the ribozyme in the in vivo setting. To overcome this technical challenge, we developed a simple in vivo strategy to accurately assess the efficiency of ribozyme cleavage that significantly enhances the computer based design programs. [source] Analogy retrieval and processing with distributed vector representationsEXPERT SYSTEMS, Issue 1 2000Tony A. Plate Holographic reduced representations (HRRs) are a method for encoding nested relational structures in fixed-width vector representations. HRRs encode relational structures as vector representations in such a way that the superficial similarity of the vectors reflects both superficial and structural similarity of the relational structures. HRRs also support a number of operations that could be very useful in psychological models of human analogy processing: fast estimation of superficial and structural similarity via a vector dot-product; finding corresponding objects in two structures; and chunking of vector representations. Although similarity assessment and discovery of corresponding objects both theoretically take exponential time to perform fully and accurately, with HRRs one can obtain approximate solutions in constant time. The accuracy of these operations with HRRs mirrors patterns of human performance on analog retrieval and processing tasks. [source] Bridging research and practice in the family and human sciences,FAMILY RELATIONS, Issue 2 2005Stephen A. Small Abstract: Over the past decade there has been a growing concern over the gap between research and practice in family and other human sciences. Family scientists have been troubled that the scientific knowledge base is not frequently used by practitioners, whereas practitioners have complained that the research base is often not very useful for issues faced in practice. The present article examines some of the reasons for the gap between research and practice and offers some suggestions for bridging it. [source] Inverse determination of the elastoplastic and damage parameters on small punch testsFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 11 2009I. PEÑUELAS ABSTRACT The small punch test (SPT) is very useful in those situations where it is necessary to use small volumes of material. The aim of this paper is to create and validate a methodology for the determination of the mechanical and damage properties of steels from the load-displacement curve obtained by means of SPTs. This methodology is based on the inverse method, the design of experiments, the polynomial curve adjustment and the evolutionary multi-objective optimization, and also allows simulating the SPTs. In order to validate the proposed methodology, the numerical results have been compared with experimental results obtained by means of normalized tests. Two dimensional axisymmetric and three-dimensional simulations have been performed in order to allow the analysis of isotropic and anisotropic materials, respectively. [source] Identification of Lophodermium seditiosum and L. pinastri in Swedish forest nurseries using species-specific PCR primers from the ribosomal ITS regionFOREST PATHOLOGY, Issue 3 2005E. Stenström Summary Lophodermium seditiosum is a serious needle pathogen on pine, particularly in nurseries, and there is a need to detect the pathogen during its latent phase. The internal transcribed spacer (ITS) regions of the rDNA of L. seditiosum and L. pinastri were amplified with universal primers and sequenced. Sequence comparisons of the two species allowed the design of species-specific primers for the ITS regions. The primers were between 18 and 24 bp long with a minimum of 3 bp differences between the species. These primer pairs did not give any amplification of DNA from any other of the examined fungal species or from healthy Pinus sylvestris needles. It was also possible to identify either L. seditiosum or L. pinastri in infected needles with and without signs of infection using these primer pairs. The method was found to be very useful for detection of latent infections of L. seditiosum in P. sylvestris needles in nurseries. Résumé Lophodermium seditiosum est un pathogène important des aiguilles sur pins, particulièrement en pépinières, et il serait nécessaire de détecter le pathogène dans sa phase latente. Les régions ITS de L. seditiosum et L. pinastri ont été amplifiées avec des amorces universelles et séquencées. La comparaison de la séquence des deux espèces a permis de développer des amorces spécifiques pour chaque espèce dans la région ITS. Les amorces ont une longueur de 18 à 24 paires de bases avec un minimum de 3 paires de bases de différence entre espèces. Ces amorces n'ont produit aucune amplification avec l'ADN des autres espèces de champignons testées ou les aiguilles saines de Pinus sylvestris. Il a également été possible de détecter L. seditiosum ou L. pinastri avec ces amorces dans des aiguilles infectées avec ou sans signe d'infection. Cette méthode s'avère très utile pour la détection d'infections latentes de L. seditiosum dans les aiguilles de P. sylvestris en pépinières. Zusammenfassung Lophodermium seditiosum ist ein starkes Nadelpathogen an Kiefern, speziell in Baumschulen. Für den Einsatz von Bekämpfungsmassnahmen wäre es von Vorteil, wenn man das Pathogen bereits während der Latenzperiode nachweisen könnte. Die ITS Regionen der ribosomalen DNA von L. seditiosum und L. pinastri wurden mit Standardprimern amplifiziert und sequenziert. Vergleiche der Sequenzen der beiden Arten erlaubten die Entwicklung von artspezifischen Primern für die ITS Regionen. Die Primerpaare waren zwischen 18 and 24 Basenpaaren lang und wiesen einen Unterschied von mindestens drei Nukleotiden auf. Die DNA von allen anderen untersuchten Pilzarten und von gesunden Pinus sylvestris Nadeln liessen sich mit keinem dieser Primerpaare amplifiziern. Lophodermium seditiosum und L. pinastri konnten mit den Primerpaaren in infizierten Nadeln mit und ohne Symptome direkt nachgewiesen werden. Die Methode eignete sich vorzüglich zum Nachweis von latenten Infektionen von L. seditiosum in P. sylvestris Nadeln in Baumschulen. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||