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Max
Kinds of Max Terms modified by Max Selected AbstractsStudy on surface morphology and selectivity of precipitated iron catalysts of FTSASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2009Wang Xingjun Abstract The precipitated iron catalyst was prepared by co-precipitation. The surface morphology of the catalyst was investigated under different reduction conditions by SEM (S-250, USA). Under H2 -reduction, the surface morphology of the catalyst had the obvious changes, which the diameter reduced, adhered together, came into being wads considered as a group. But the surface morphology of the catalyst had almost no change under CO reduction. The crystal structure of the catalyst was studied under different reduction conditions by X-ray diffraction (XRD) (Rigaku D/max, Japanese). It was found that the catalyst was reduced completely with H2, but it was reduced partly with CO. The crystal structure of the catalyst converted into the metallic phase with H2 reduction. However, most of the iron converted into iron oxide (Fe3O4) with CO reduction. And the predominant phase in a sample of a mature catalyst is ,-Fe5C2, which is the active phase in the Fischer-Tropsch synthesis (FTS). The experimental results showed that CO conversion and H2 conversion increase with the change of reaction temperature from 260 to 300 °C, under the conditions of pressure P = 2.6 MPa, space velocity = 0.86 Nl h,1 g-Fe,1, n(H2)/n(CO) = 2/3, and most of the hydrocarbon products are C5,11 which hold half of the hydrocarbon products. The next content is C2,4 which holds the quarter of hydrocarbon products. Then it is C12+, which is equal to 18%. And the last is C1, which is equal to 7%. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Generation of a virtual reality-based automotive driving training system for CAD educationCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2009Janus Liang Abstract Designing and constructing a virtual reality-based system is useful for educating students about scenario planning, geometric modeling and computer graphics. In particular, students are exposed to the practical issues surrounding topics such as geometric modeling, rendering, collision detection, model animation and graphical design. Meanwhile, building an application system provides students exposure to the real-world side of software engineering that they are typically shielded from in the traditional computer class. This study is a description of the experiences with instructing "Computer-aided Industrial design" and "OOP," two introductory classes that focus on designing and generating the VR based system possible in the course of a semester and then "VR System," an advanced course in the next semester. This study emphasizes the continuing evolution in the training and educational needs of students of CAD-systems. This study breaks down an automobile driving training system into different components that are suitable for individual student projects and discusses the use of modern graphical design tools such as 3ds MAX for artistic design in this system. The conclusion of this study proposes a rough schedule for developing a VR based system during the course of a semester and an overview is given of a concept of a virtual reality-based design and constructing system that is being developed. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 148,166, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae20178 [source] Determination of flurbiprofen enantiomers in plasma using a single-isomer amino cyclodextrin derivative in nonaqueous capillary electrophoresis,ELECTROPHORESIS, Issue 17 2008Anne Rousseau Abstract A nonaqueous capillary electrophoresis (NACE) assay was developed for the separation and determination of flurbiprofen enantiomers in plasma samples using 6-monodeoxy-6-mono(3-hydroxy)propylamino-,-cyclodextrin as chiral selector. The nonaqueous background electrolyte was made up of 40,mM ammonium acetate in methanol (MeOH), and flufenamic acid was employed as internal standard. Solid-phase extraction was used for sample cleanup prior to the NACE separation. The NACE method reproducibility was optimized by evaluating different capillary washing sequences between runs. After having tested various conditions, trifluoroacetic acid (1,M) in MeOH was finally selected. Concerning the solid-phase extraction procedure, good and reproducible analyte recoveries were obtained using MeOH for protein denaturation and a polymeric phase combining hydrophobic interactions with anion exchange properties (Oasis® MAX) was selected as extraction sorbent. The method selectivity was not only demonstrated toward a blank plasma sample but also toward other non-steroidal anti-inflammatory drugs. The method was then successfully validated with respect to response function, trueness, precision, accuracy, linearity and limit of quantification. [source] Minimal and maximal goal orientation and reactions to norm violationsEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 1 2009Immo Fritsche Violations of social norms can either be evaluated in an absolute or in a gradual fashion depending on whether group goals are represented as minimal or maximal goals. Recent research has shown that absolute versus gradual deviations lead to increased levels of demanded punishment and inclination to exclude the deviant from the respective moral community. In this article, we investigate whether individual differences in orientation towards setting goals in either minimal or maximal terms predict reactions to norm violation. In three studies we found that a dominant minimal goal orientation (MIN) relative to maximal goal orientation (MAX) increased punishment inclinations and social exclusion tendencies towards norm violators. These effects were mediated by affective reaction and proved to be unique goal orientation effects when possible effects of need for closure, intolerance of ambiguity and regulatory focus were controlled for. Copyright © 2008 John Wiley & Sons, Ltd. [source] Efficient computation for the noisy MAXINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 2 2003Francisco J. Díez Díez's algorithm for the noisy MAX is very efficient for polytrees, but when the network has loops, it has to be combined with local conditioning, a suboptimal propagation algorithm. Other algorithms, based on several factorizations of the conditional probability of the noisy MAX, are not as efficient for polytrees but can be combined with general propagation algorithms such as clustering or variable elimination, which are more efficient for networks with loops. In this article we propose a new factorization of the noisy MAX that amounts to Díez's algorithm in the case of polytrees and at the same time is more efficient than previous factorizations when combined with either variable elimination or clustering. © 2003 Wiley Periodicals, Inc. [source] Accounting for uncertainty in QTL location in marker-assisted pre-selection of young bulls prior to progeny testJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 1 2002A. STELLA The objective of this study was to evaluate whether the efficacy of marker assisted selection (MAS) could be improved by considering a confidence interval (CI) of QTL position. Specifically, MAS was applied for within-family selection in a stochastic simulation of a closed nucleus herd. The location and effect of the QTL were estimated by least squares interval mapping with a granddaughter design and marker information was then used in a top down scheme. Three approaches were used to select the best bull within full sibships of 3 or 40 bulls. All three were based on the probability of inheriting the favorable allele from the grandsire (PROB). The first method selected the sib with the highest PROB at the location with the highest F-ratio (MAX). The other two approaches were based on sums of estimated regression coefficients weighted by PROB at each cM within a 95% CI based on either bootstrapping (BOOT) or approximate LOD scores (LOD). Accounting for CI increased the relative genetic gain in all scenarios. The average breeding value (BV) of the selected bulls was increased by 2.00, 2.60 and 2.59% when MAS was applied using MAX, BOOT and LOD, respectively, compared to random selection (h2=0.30). Selected bulls carried the correct allele in 63.0, 68.5, 67.6 and 50.1% of the cases for MAX, BOOT, LOD and random selection, respectively. Berü;cksichtigung der Unsicherheit von QTL Positionen bei Marker-gestü;tzter Vorselektion von jungen Bullen vor der Nachkommenprü;fung Das Ziel dieser Studie war es zu prüfen, ob die Effizienz von MAS (Marker gestützte Selektion) durch Berücksichtigung des Konfidenzintervalls (CI) einer QTL Position verbessert werden kann. Es wurde MAS bei der Selektion innerhalb Familien in einer geschlossenen Nukleus Herde in einer stochastischen Simulation angewandt. Die Postition und der Effekt des QTL wurden in einem Granddaughter Design mit einer Least=Square Intervall Kartierung geschätzt. Die Marker Informationen wurden dann in einem top-down-Schema verwendet. Drei Ansätze fanden Verwendung, um den besten Bullen innerhalb von Vollgeschwistern von 3 oder 40 Bullen zu selektieren. Alle drei Ansätze basieren auf der Wahrscheinlichkeit, ein zu bevorzugendes Allel vom Grossvater zu erben (PROB). Bei der ersten Methode wurden die Geschwister mit der höchsten PROB an der Position mit dem höchsten F-Wert selektiert (MAX). Die beiden anderen Ansätze basierten auf den Summen der geschätzten Regressionskoeffizienten, gewichtet nach PROB an jedem cM innerhalb eines 95%igen CI, das entweder auf Bootstrapping (BOOT) oder approximativen LOD Scores (LOD) basiert. Die Berücksichtigung des CI vergrösserte den relativen genetischen Fortschritt in allen Szenarien. Bei Anwendung von MAS waren die durchschnittlichen Zuchtwerte der selektierten Bullen bei Verwendung von MAX, BOOT und LOD verglichen mit zufälliger Selektion (h2=0,30) um 2,00, 2,60 und 2,59% gestiegen. Die selektierten Bullen trugen das richtige Allel bei den entsprechenden Berechnungen MAX, BOOT, LOD und zufälliger Selektion in 63,0, 68,5, 67,6 und 50,1% der Fälle. [source] Comparison of mixed-mode anion-exchange performance of N -vinylimidazole-divinylbenzene sorbentJOURNAL OF SEPARATION SCIENCE, JSS, Issue 11 2006Núria Fontanals Abstract A newly synthesized copolymer based on N -vinylimidazole-divinylbenzene (NVIm-DVB) was evaluated as a mixed-mode anion-exchange sorbent for SPE, since the NVIm monomer apart from its hydrophilic properties can be protonated at a certain pH, and then performs as an anion-exchanger. To investigate the behavior of the NVIm-based sorbent, the SPE performance was evaluated under reversed-phase (RP), weak anion-exchange, and strong anion-exchange conditions. The results for the NVIm-DVB sorbent were also compared to commercial reference sorbents from each group: Oasis HLB, Oasis WAX, and Oasis MAX, respectively. SPE results from this evaluation showed that NVIm-DVB can be used as an RP material, compared to Oasis HLB. It also has the potential to act as a strong anion-exchange sorbent, compared to Oasis MAX, since under the proper conditions it was able to fraction and quantitatively recover a group of selected solutes. [source] The crystallography beamline I711 at MAX,IIJOURNAL OF SYNCHROTRON RADIATION, Issue 4 2000Y. Cerenius A new X-ray crystallographic beamline is operational at the MAX,II synchrotron in Lund. The beamline has been in regular use since August 1998 and is used both for macro- and small molecule diffraction as well as powder diffraction experiments. The radiation source is a 1.8,T multipole wiggler. The beam is focused vertically by a bendable mirror and horizontally by an asymmetrically cut Si(111) monochromator. The wavelength range is 0.8,1.55,Å with a measured flux at 1,Å of more than 1011,photons,s,1 in 0.3,mm × 0.3,mm at the sample position. The station is currently equipped with a Mar345 imaging plate, a Bruker Smart 1000 area CCD detector and a Huber imaging-plate Guinier camera. An ADSC 210 area CCD detector is planned to be installed during 2000. [source] The bi-criteria doubly weighted center-median path problem on a treeNETWORKS: AN INTERNATIONAL JOURNAL, Issue 4 2006J. Puerto Abstract Given a tree network T with n nodes, let ,,L be the subset of all discrete paths whose length is bounded above by a prespecified value L. We consider the location of a path-shaped facility P , ,,L, where customers are represented by the nodes of the tree. We use a bi-criteria model to represent the total transportation cost of the customers to the facility. Each node is associated with a pair of nonnegative weights: the center-weight and the median-weight. In this doubly weighted model, a path P is assigned a pair of values (MAX(P),SUM(P)), which are, respectively, the maximum center-weighted distance and the sum of the median-weighted distances from P to the nodes of the tree. Viewing ,,L and the planar set {(MAX(P),SUM(P)) : P , ,,L} as the decision space and the bi-criteria or outcome space respectively, we focus on finding all the nondominated points of the bi-criteria space. We prove that there are at most 2n nondominated outcomes, even though the total number of efficient paths can be ,(n2), and they can all be generated in O(n log n) optimal time. We apply this result to solve the cent-dian model, whose objective is a convex combination of the weighted center and weighted median functions. We also solve the restricted models, where the goal is to minimize one of the two functions MAX or SUM, subject to an upper bound on the other one, both with and without a constraint on the length of the path. All these problems are solved in linear time, once the set of nondominated outcomes has been obtained, which in turn, results in an overall complexity of O(n log n). The latter bounds improve upon the best known results by a factor of O(log n). © 2006 Wiley Periodicals, Inc. NETWORKS, Vol. 47(4), 237,247 2006 [source] A unified framework for obtaining improved approximation algorithms for maximum graph bisection problems,RANDOM STRUCTURES AND ALGORITHMS, Issue 3 2002Eran Halperin We obtain improved semidefinite programming based approximation algorithms for all the natural maximum bisection problems of graphs. Among the problems considered are: MAX -BISECTION,partition the vertices of the graph into two sets of equal size such that the total weight of edges connecting vertices from different sides is maximized; MAX -VERTEX-COVER,find a set containing half of the vertices such that the total weight of edges touching this set is maximized; MAX -DENSE-SUBGRAPH,find a set containing half of the vertices such that the total weight of edges connecting two vertices from this set is maximized; and MAXUNCUT,partition the vertices into two sets of equal size such that the total weight of edges that do not cross the cut is maximized. We also consider the directed versions of these problems, such as MAX -DIRECTED-BISECTION and MAX -DIRECTED-UNCUT. These results can be used to obtain improved approximation algorithms for the unbalanced versions of the partition problems mentioned above, where we want to partition the graph into two sets of size and , where is not necessarily . Our results improve, extend and unify results of Frieze and Jerrum, Feige and Langberg, Ye, and others. All these results may be viewed as extensions of the MAX CUT algorithm of Goemans and Williamson, and the MAX 2-SAT and MAX DI-CUT algorithms of Feige and Goemans. © 2002 Wiley Periodicals, Inc. Random Struct. Alg., 20:382,402, 2002 [source] SlCCD7 controls strigolactone biosynthesis, shoot branching and mycorrhiza-induced apocarotenoid formation in tomatoTHE PLANT JOURNAL, Issue 2 2010Jonathan T. Vogel Summary The regulation of shoot branching is an essential determinant of plant architecture, integrating multiple external and internal signals. One of the signaling pathways regulating branching involves the MAX (more axillary branches) genes. Two of the genes within this pathway, MAX3/CCD7 and MAX4/CCD8, encode carotenoid cleavage enzymes involved in generating a branch-inhibiting hormone, recently identified as strigolactone. Here, we report the cloning of SlCCD7 from tomato. As in other species, SlCCD7 encodes an enzyme capable of cleaving cyclic and acyclic carotenoids. However, the SlCCD7 protein has 30 additional amino acids of unknown function at its C terminus. Tomato plants expressing a SlCCD7 antisense construct display greatly increased branching. To reveal the underlying changes of this strong physiological phenotype, a metabolomic screen was conducted. With the exception of a reduction of stem amino acid content in the transgenic lines, no major changes were observed. In contrast, targeted analysis of the same plants revealed significantly decreased levels of strigolactone. There were no significant changes in root carotenoids, indicating that relatively little substrate is required to produce the bioactive strigolactones. The germination rate of Orobanche ramosa seeds was reduced by up to 90% on application of extract from the SlCCD7 antisense lines, compared with the wild type. Additionally, upon mycorrhizal colonization, C13 cyclohexenone and C14 mycorradicin apocarotenoid levels were greatly reduced in the roots of the antisense lines, implicating SlCCD7 in their biosynthesis. This work demonstrates the diverse roles of MAX3/CCD7 in strigolactone production, shoot branching, source,sink interactions and production of arbuscular mycorrhiza-induced apocarotenoids. [source] AtMBD9: a protein with a methyl-CpG-binding domain regulates flowering time and shoot branching in ArabidopsisTHE PLANT JOURNAL, Issue 2 2006Mingsheng Peng Summary The functional characterization of mammalian proteins containing a methyl-CpG-binding domain (MBD) has revealed that MBD proteins can decipher the epigenetic information encoded by DNA methylation, and integrate DNA methylation, modification of chromatin structure and repression of gene expression. The Arabidopsis genome has 13 putative genes encoding MBD proteins, and no specific biological function has been defined for any AtMBD genes. In this study, we identified three T-DNA insertion mutant alleles at the AtMBD9 locus, and found that all of them exhibited obvious developmental abnormalities. First, the atmbd9 mutants flowered significantly earlier than wild-type plants. The expression of FLOWERING LOCUS C (FLC), a major repressor of Arabidopsis flowering, was markedly attenuated by the AtMBD9 mutations. This FLC transcription reduction was associated with a significant decrease in the acetylation level in histone H3 and H4 of FLC chromatin in the atmbd9 mutants. Secondly, the atmbd9 mutants produced more shoot branches by increasing the outgrowth of axillary buds when compared with wild-type plants. The two known major factors controlling the outgrowth of axillary buds in Arabidopsis, auxin and the more axillary growth (MAX) pathway, were found not to be involved in producing this enhanced shoot branching phenotype in atmbd9 mutants, indicating that AtMBD9 may regulate a novel pathway to control shoot branching. This pathway is not related to FLC expression as over-expression of FLC in atmbd9-2 restored its flowering time to one similar to that of the wild type, but did not alter the shoot branching phenotype. [source] Pearson's Test, Trend Test, and MAX Are All Trend Tests with Different Types of ScoresANNALS OF HUMAN GENETICS, Issue 2 2009Gang Zheng Summary Pearson's test is one of the most commonly used statistics for testing genetic association of case-control data. The trend test is another one which assumes a dose-response model between the risk of the disease and genotypes. To apply the trend test, a set of ordered scores is assigned a priori based on the underlying genetic model. Pearson's test is model-free and robust, but is less powerful for common genetic models. MAX is another robust test statistic, which takes the maximum of the trend tests over a family of scientifically plausible genetic models. We show that the three test statistics are all trend tests but with different types of scores; whether the scores are prespecified or data-driven, or whether the scores are ordered (restricted) or not ordered (unrestricted). We then provide insights into power performance of the three tests when the underlying genetic model is unknown and discuss which test to use for the analyses of case-control genetic association studies. [source] Robust Tests for Single-marker Analysis in Case-Control Genetic Association StudiesANNALS OF HUMAN GENETICS, Issue 2 2009Qizhai Li Summary Choosing an appropriate single-marker association test is critical to the success of case-control genetic association studies. An ideal single-marker analysis should have robust performance across a wide range of potential disease risk models. MAX was designed specifically to achieve such robustness. In this work, we derived the power calculation formula for MAX and conducted a comprehensive power comparison between MAX and two other commonly used single-marker tests, the one-degree-of-freedom (1-df) Cochran-Armitage trend test and the 2-df Pearson ,2 test. We used a single-marker disease risk model and a two-marker haplotype risk model to explore the performances of the above three tests. We found that each test has its own "sweet" spots. Among the three tests considered, MAX appears to have the most robust performance. [source] Decreasing trophic efficiency in cool-water aquaculture ponds: size-selective predation removes large preyAQUACULTURE RESEARCH, Issue 5 2009Chelsea O Bennice Abstract Maximizing young-of-year (YOY) fish production in an aquaculture setting depends on matching predatory demand with prey availability. With a size-selective YOY fish species (saugeye: Sander vitreus Mitchell females ×S. canadense Griffith & Smith males) supplied with natural zooplankton prey (Bosmina sp. Baird), selective removal of larger individuals may decrease prey fecundity. However, increased nutrient fertilization may also ameliorate the top-down effects of fish predation. We tested these interactions in outdoor earthen production ponds (ca. 4000 m2; n=12) by measuring Bosmina sp. size at first reproduction (SFR), maximum size (MAX) and neonate size (NEO) in ponds that varied in YOY saugeye densities (18,50 saugeye m,3) and also differed in phosphorus maintenance levels (either 20 or 30 ,g PO4 -P L,1). We found that SFR decreased by 8% [from 0.298 mm±0.007 (mean±1 SE) to 0.275 mm±0.005], MAX decreased by 11% (from 0.367 mm±0.009 to 0.328 mm±0.009) and NEO decreased by 5% (0.198 mm±0.004 to 0.189 mm±0.003) over the range of saugeye densities, and that SFR increased by 4% (from 0.279 mm±0.004 to 0.290 mm±0.003) and MAX increased by 3% (from 0.336 mm±0.004 to 0.347±0.004) with increased fertilization. Further, prey offspring lengths strongly related to mother lengths and lengths differed from early to late in the production season. These results indicate that multiple factors affect prey sizes and emphasize that the removal of large prey individuals by size-selective YOY predators may decrease trophic efficiency, ultimately decreasing fish production. [source] Determination of S -phenylmercapturic acid in human urine using an automated sample extraction and fast liquid chromatography-tandem mass spectrometric methodBIOMEDICAL CHROMATOGRAPHY, Issue 6-7 2006Yinghe Li Abstract S -phenylmercapturic acid is widely accepted as a specific biomarker for the evaluation of benzene exposure. Here, we describe a fast, specific and sensitive high-performance liquid achromatography coupled with tandem mass spectrometry (LC-MS/MS) method that has been developed and validated for the determination of S- phenylmercapturic acid in human urine. Isotope-labeled S- phenylmercapturic acid- d5 was used as internal standard to improve the method ruggedness. The fully automated solid-phase extraction method on a 96-well Oasis MAX (mix-mode anion exchange) plate was employed to clean up the urine samples before analysis. The rapid LC-MS/MS analysis of extracted samples was achieved on a Genesis C18 column with a run time of only 3 min. Negative electrospray ionization with multiple reaction monitoring (ESI-MRM) mode was used to detect S- phenylmercapturic acid (m/z 238 , 109) and S- phenylmercapturic acid - d5 (m/z 243 , 114). The method fulfils all the standard requirements of method validation. The calibration curve was linear within the concentration range 0.400,200 ng/mL. The method performed accurately and precisely in validation with <7.5% relative error and <6.5% relative standard deviation of quality control samples. The method efficacy was also verified by the analysis of urine samples from 12 smokers and 12 non-smokers. With the fully automated sample cleanup procedure and the fast LC-MS/MS analysis, a sample analysis throughput of 384 samples per day could be achieved. Copyright © 2006 John Wiley & Sons, Ltd. [source] 2357: Autonomic nervous system and endothelial peripheral dysfunction in normal tension glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2010J WIERZBOWSKA Purpose To define parameters of autonomic nervous system activity and peripheral vascular reactive hyperemia in normal tension glaucoma patients. Methods Ambulatory 24-hour electrocardiogram and blood pressure (BP) monitoring by using Lifecard CF and SpaceLab 90207-30 combined with occlusion provocation test were carried out in 54 NTG patients (44 women, mean age 59.7) and 43 matched control subjects (34 women, mean age 57.0). Heart rate variability (HRV) time and frequency domain parameters [low-frequency (LF), high-frequency (HR) and LF/HF ratio], and blood pressure variability (BPV) were calculated and analyzed for both study groups. Postocclusive hyperemia response parameters (TM - time to peak flow, TH ,half-time hyperaemia, TR ,time to rest flow, BZ-biological zero and MAX , maximum hyperemic response) were compared for patients with a nocturnal fall in mean BP (MPB) of less than 10% (non-dippers), of 10-20% (dippers) and of more than 20% (over-dippers) Results NTG patients demonstrated higher LF and LF/HF values for 24-hour period, day-time and night time than control subjects. There was no difference in BPV between study groups (10.4 ± 1.9 vs. 10.5 ± 2.1, p=0.790). In NTG patients, TH was significantly higher (79.0 ± 80.9 s vs. 51.5 ± 35.3 s, p=0.028) and BZ was significantly lower (2.3 ± 1.0 vs. 3.1 ± 2.0, p=0.009) as compared to the control group. There was statistically significant difference between NTG non-dippers, dippers and over,dippers in the BZ parameter (2.3 ± 0.9 vs. 2.7 ± 1.3 vs. 1.4 ± 0.4 p=0.024). Conclusion NTG patients exhibit abnormal ANS system activity and a different systemic hyperemia response as compared with healthy subjects. [source] Abnormal peripheral vascular response to occlusion provocation in normal tension glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2007J WIERZBOWSKA Purpose: To assess peripheral vascular reactive hyperemia in response to occlusion provocation test, using two-channels laser Doppler probe in patients with normal tension glaucoma (NTG) and normal subjects. Methods: 15 patients with NTG (12 women and 4 men), mean aged 58,9 and 15 control subjects (13 women and 2 men), mean aged 60,6 were subjected to an occlusion test. The experiment comprised following steps: 1/ a 5-minute baseline-period 2/ a 2-minute occlusion of the left hand using a 15 cm wide cuff located directly over the elbow (the pressure in the cuff was 50 mmHg higher than the systolic pressure measured on the arm 3/ a 15- minute final recovery period after occlusion. Finger hyperemia was assessed by two-channels laser-Doppler flowmeter MBF-3d, Moor Instruments, Ltd., continuously during the experiment. For measurements of hyperemia two surface probes were attached to the pulp of the second finger (mean probe) and third finger (basic probe) of the left hand. The following hyperemia parameters were measured: RF (rest flow), BZ (biological zero), TM (time to peak flow), TH (half-time of hyperemia), MAX (maximum of hyperemia) and hyperemia amplitude (MAX-RF)/RF 100% was calculated. Kruskal-Wallis test analysis was used to test the differences between the group of patients and normal subjects for TM1,MXF1 (basic probe) and TM2, MXF2 (mean probe) parameters. Results: In NTG patients, TM1 was significantly higher comparing with healthy subjects whereas MAX was significantly lower as compared to the control group. Conclusions: Occlusion provocation test elicits a different systemic hyperemia response in patients with NTG compared with healthy subjects. [source] Prostaglandin E2 promotes cell proliferation via protein kinase C/extracellular signal regulated kinase pathway-dependent induction of c-Myc expression in human esophageal squamous cell carcinoma cellsINTERNATIONAL JOURNAL OF CANCER, Issue 11 2009Le Yu Abstract Overexpression of cyclooxygenase-2 (COX-2) and elevation of its derivative prostaglandin E2 (PGE2) are implicated in human esophageal squamous cell carcinoma. The expression of c-Myc, an oncogenic transcription factor, is also upregulated in this malignant disease. This study sought to elucidate whether a functional connection exists between COX-2/PGE2 and c-Myc in esophageal squamous cell carcinoma. Results showed that PGE2 substantially increased the proliferation of cultured esophageal squamous cell carcinoma cells. In this regard, PGE2 substantially increased the mRNA and protein expression of c-Myc and its association with the binding partner Max. Knockdown of c-Myc by RNA interference also significantly attenuated PGE2 -induced cell proliferation. Further, mechanistic study revealed that PGE2 increased the protein stability and nuclear accumulation of c-Myc via phosphorylation on serine 62 in an extracellular signal regulated kinase (ERK)-dependent manner. To this end, ERK activation by PGE2 was completely abolished by protein kinase C (PKC) inhibitors. Moreover, the effect of PGE2 on c-Myc expression was mimicked by EP2 receptor agonist. In addition, knockdown of EP2 receptor by EP2 siRNA attenuated PGE2 -induced c-Myc expression. Collectively, our findings suggest that PGE2 upregulates c-Myc via the EP2/PKC/ERK pathway. This study sheds new light on the carcinogenic mechanism of PGE2 in esophageal squamous cell carcinoma. © 2009 UICC [source] Early nuclear exclusion of the transcription factor max is associated with retinal ganglion cell death independent of caspase activityJOURNAL OF CELLULAR PHYSIOLOGY, Issue 2 2004Hilda Petrs-Silva We examined the behavior of the transcription factor Max during retrograde neuronal degeneration of retinal ganglion cells. Using immunohistochemistry, we found a progressive redistribution of full-length Max from the nucleus to the cytoplasm and dendrites of the ganglion cells following axon damage. Then, the axotomized cells lose all their content of Max, while undergoing nuclear pyknosis and apoptotic cell death. After treatment of retinal explants with either anisomycin or thapsigargin, the rate of nuclear exclusion of Max accompanied the rate of cell death as modulated by either drug. Treatment with a pan-caspase inhibitor abolished both TUNEL staining and immunoreactivity for activated caspase-3, but did not affect the subcellular redistribution of Max immunoreactivity after axotomy. The data show that nuclear exclusion of the transcription factor Max is an early event, which precedes and is independent of the activation of caspases, during apoptotic cell death in the central nervous system. J. Cell. Physiol. 198: 179,187, 2004© 2003 Wiley-Liss, Inc. [source] Improving the interaction of Myc-interfering peptides with Myc using molecular dynamics simulationsJOURNAL OF PEPTIDE SCIENCE, Issue 1 2009Eva M. Jouaux Abstract Previously, a Myc-interfering peptide (Mip) was identified for the targeted inactivation of the Myc:Max complex by the combination of rational design and an in vivo protein-fragment complementation assay. In the subsequent work presented here, molecular dynamics simulations and free energy calculations based on the molecular mechanics GBSA method were performed to define the contribution of the different amino acids in the Myc:Mip coiled coil domain, and compared to wild-type Myc:Max. For further optimization of the Myc interference, point mutations were introduced into Mip and analyzed, from which two showed much higher binding affinities in the computational studies in good agreement with the experiment. These mutants with very high potential for inactivation of Myc can now be used as starting point for further optimizations based on the computational as well as experimental protocols presented here. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd. [source] Targeting the c-Myc coiled coil with interfering peptidesJOURNAL OF PEPTIDE SCIENCE, Issue 9 2008Eva M. Jouaux Abstract c-Myc is one of the most frequently deregulated oncogenes in human cancers, and recent studies showed that even brief inactivation of Myc can be sufficient to induce tumor regression or loss. Consequently, inactivation of Myc provides a novel therapeutic opportunity and challenge, as the dimerization of Myc with Max is crucial for its function. We applied two strategies to specifically target this coiled coil mediated interaction with interfering peptides: a dominant-negative human Max sequence (Max) and a peptide selected from a genetic library (Mip). Both peptides form coiled coils and were fused to an acidic extension interacting with the basic DNA-binding region of human Myc. The genetic library was obtained by semi-rational design randomizing residues important for interaction, and selection was carried out using a protein-fragment complementation assay. The peptides Max and Mip easily outcompeted the human Myc:Max interaction and successfully interfered with the DNA binding of the complex. Both interfering peptides exhibited higher Tm (,Tm = 13 and 15 °C) upon interaction with Myc compared to wt Max. The inhibitory effect of the two interfering peptides on human Myc:Max activity makes them promising molecules for analytical and therapeutic Myc-directed research. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd. [source] In vivo comparison of the relative systemic bioavailability of fluticasone propionate from three anti-static spacers and a metered dose inhalerBRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 2 2009Arun Nair WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT , Conventional spacers help overcome problems with co-ordination and may improve lung deposition and decrease oropharyngeal impaction. , Antistatic spacers eliminate electrostatic charge and may hence improve respirable dose delivery. , The systemic bioavailability of inhaled fluticasone propionate is primarily dependent on delivery by the pulmonary route and hence the performance of antistatic spacers can be evaluated using adrenal suppression as a sensitive surrogate for relative bioavailability to the lung after an inhalation. WHAT THIS STUDY ADDS , This study compares the relative bioavailability to the lung of inhaled fluticasone delivered via conventional pressurized metered dose inhalers (pMDI) and three antistatic spacers (plastic Zerostat-V, plastic Aerochamber Max, and metal Nebuchamber) in patients with asthma. , All three antistatic spacers when compared with pMDI significantly increased the relative bioavailability to the lungs of inhaled fluticasone in terms of relative adrenal suppression, and there were no significant differences between the plastic and metal antistatic spacers. AIMS The systemic bioavailability of inhaled fluticasone propionate (FP) depends primarily on lung absorption and can be quantified by measuring suppression of overnight and early morning urinary cortisol/creatinine (OUCC and EMUCC, respectively). The aim of the study was to determine the relative bioavailability of hydrofluoroalkane (HFA) FP to the lungs via anti-static plastic (Zerostat-V and Aerochamber Max), metal (Nebuchamber) anti-static spacers and metered dose inhaler [Flixotide Evohaler (EH) (pMDI)]. METHODS A randomized, double-blind, double-dummy, four-way crossover design was used. Eighteen mild to moderate asthmatics received single doses of placebo/HFA-FP 2 mg via the 280-ml Zerostat-V (ZS); 250-ml Nebuchamber (NC); 197-ml Aerochamber Max (AC); and pMDI (EH). Measurements of OUCC and EMUCC were made at baseline and 10 h after each dose. RESULTS Significant suppression of OUCC and EMUCC occurred from baseline with all three spacers, but not Evohaler (geometric mean fold suppression, 95% confidence interval): ZS, 2.74 (1.75, 4.30), P < 0.001; NC, 3.31 (1.81, 6.06), P < 0.001; AC, 4.98 (3.39, 7.31), P < 0.001; and for EH this was 1.42 (0.92, 2.21), P= 0.169 (equating to a 64, 70, 80 and 30% fall in OUCC via the ZS, NC, AC and EH devices, respectively). There were significant differences between all three spacers vs. EH. When compared with the Evohaler, the Zerostat V resulted in 48% greater suppression (P= 0.009); the Nebuchamber 57% greater suppression (P= 0.001); and the Aerochamber Max 71% greater suppression of OUCC (P < 0.001). CONCLUSION All three antistatic spacers significantly increased the relative systemic bioavailability of HFA-FP compared with the standard pMDI. [source] Pharmacodynamic differentiation of lorazepam sleepiness and dizziness using an ordered categorical measureJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 8 2010Mohamed A. Kamal Abstract Categorical measures of lorazepam sleepiness and dizziness were modeled to identify differences in pharmacodynamic (PD) parameters between these adverse events (AEs). Differences in data-derived PD parameters were compared with relative incidence rates in the drug label (15.7% and 6.9%, respectively). Healthy volunteers (n,=,20) received single oral doses of 2,mg lorazepam or placebo in a randomized, double-blind, cross-over fashion. A seven-point categorical scale measuring the intensity of AEs was serially administered over 24,h. The maximum score (MaxS), and area under the effect curve (AUEC) were determined by noncompartmental methods and compared using a paired t -test. Individual scores were modeled using a logistic function implemented in NONMEM. AUEC and MaxS for sleepiness were significantly higher than dizziness (20.35 vs. 9.76, p,<,0.01) and (2.35 vs. 1.45, p,<,0.01). Model slope estimates were similar for sleepiness and dizziness (0.21,logits,×,mL/ng vs. 0.19,logits,×,mL/ng), but baseline logits were significantly higher for sleepiness (,2.81 vs. ,4.34,logits). Data-derived PD parameters were in concordance with label incidence rates. The higher intensity of sleepiness may be directly related to baseline (no drug present) while the increase in intensity as a result of drug was relatively similar for both AEs. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:3628,3641, 2010 [source] Evaluation of serum cystatin C levels and 99mTechnetium-mercaptoacetyltriglycine-3 renal scintigraphy for the early detection of cisplatin-induced renal toxicity in cancer patientsNEPHROLOGY, Issue 2 2002Nazan GÜNEL SUMMARY: Cisplatin has a broad-spectrum antineoplastic activity. Nephrotoxicity is a prominent component of the toxicity profile of cisplatin-based chemotherapy. In recent years, several reports have confirmed that cystatin C (cys-C) demonstrates a better correlation with the glomerular filtration rate than with serum creatinine. Scintigraphic techniques are also widely used in evaluating renal function. In the present study, serum cys-C, serum creatinine concentrations and 99mTechnetium-mercaptoacetyltriglycine-3 (99mTc-MAG-3) scintigraphy were studied in 22 cisplatin-naive cancer patients, 3 days before and 24 h after the first cycle of cisplatin-based chemotherapy. Serum cystatin C and creatinine levels increased in cancer patients after chemotherapy (creatinine: from 68 ± 12 to 72 ± 17 nmol/L; cystatin-C: from 0.064 ± 0.025 to 0.072 ± 0.033 jimol/L), but these differences were not statistically significant (P>0.05). Semiquantitative variables of 99mTc-MAG-S scintigraphy significantly elevated after chemotherapy (T½*: from 10.27 ± 5.00to 16.17 ± 9.40 min, R20/max*: from 0.40 ± 0.12 to 0.67+0.45, Tmax**: from 5.40 ± 4.01 to 7.59 ± 5.30 min; *P<0.001, **P<0.01, respectively). These results suggest that MAG-3 scintigraphy is a highly sensitive method in the early detection of cisplatin-induced nephrotoxicity. Serum cystatin C doesn't seem to play a role in the early detection of cisplatin-induced nephrotoxicity. As a result, MAG-3 scintigraphy may be used in selected patients who have a predisposition for renal toxicity. [source] Simultaneous determination of metronidazole and spiramycin in bulk powder and in tablets using different spectrophotometric techniquesDRUG TESTING AND ANALYSIS, Issue 1 2010Fatma I. Khattab Abstract Metronidazole (MZ) is an anti-infective drug used in the treatment of anaerobic bacterial and protozoa infections in humans. It is also used as a vetinary antiparasitic drug. Spiramycin (SP) is a medium-spectrum antibiotic with high effectiveness against Gram-positive bacteria. Three simple, sensitive, selective and precise spectrophotometric methods were developed and validated for the simultaneous determination of MZ and SP in their pure form and in pharmaceutical formulations. In methods A and B, MZ was determined by the application of direct spectrophotometry and by measuring its zero-order (D0) absorption spectra at its ,max = 311 nm. In method A, SP was determined by the application of first derivative spectrophotometry (D1) and by measuring the amplitude at 218.3 nm. In method B, the first derivative of the ratio spectra (DD1) was applied, and SP was determined by measuring the peak amplitude at 245.6 nm. Method C entailed mean centring of the ratio spectra (MCR), which allows the determination of both MZ and SP. The methods developed were used for the determination of MZ and SP over a concentration range of 5,25 µg ml,1. The proposed methods were used to determine both drugs in their pure, powdered forms with mean percentage recoveries of 100.16 ± 0.73 for MZ in methods A and B, 101.10 ± 0.90 in method C, 100.09 ± 0.70, 100.02 ± 0.88 and 100.49 ± 1.26 for SP in methods A, B and C, respectively. The proposed methods were proved using laboratory-prepared mixtures of the two drugs and were successfully applied to the analysis of MZ and SP in tablet formulation without any interference from each other or from the excipients. The results obtained by applying the proposed methods were compared statistically with a reported HPLC method and no significant difference was observed between these methods regarding both accuracy and precision. Copyright © 2010 John Wiley & Sons, Ltd. [source] Effect of Ti addition on magnetic properties of TbCu7 -type Sm-Fe-Co-Mn system nitridesELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 7 2008Hiroshi Yamamoto Abstract To support the development of high-performance isotropic bonded magnets, experiments were carried out to investigate the effect of Ti addition on the magnetic properties of Sm-Fe-Co-Mn system nitride compounds with TbCu7 -type structure. Sm10(Fe0.9Co0.1)89.5,xMn0.5Tix (x=0 to 1.0) alloy ribbons were prepared by the single-roller rapid-quenching method. The effects of alloy composition and of heat treatment and nitriding conditions on the magnetic properties were examined. The optimum preparation conditions of the compounds were as follows. Composition: {Sm10(F0.9Co0.1)89Mn0.5Ti0.5}86.8N13.2; roller speed: 50 m/s; heat treatment: 700°C×60 min in high-purity Ar gas; nitriding conditions: 420°C×15 h in high-purity N2 gas. Typical magnetic properties of the obtained compound powders were Jr = 0.97 T, HcJ = 730.8 kA/m,(BH)max = 140.0 kJ/m3 (17.6 MGOe), Tc=500°C. XRD, TEM photographs, and recoil loops of the hysteresis curve demonstrated that this sample had the characteristics of an exchange spring magnet. The value of (BH)max for the isotropic compression molding bonded magnet prepared from the {Sm10(F0.9Co0.1)89Mn0.5Ti0.5}86.8N13.2 powder was 94.8 kJ/m3 (11.9 MGOe) at a bonded magnet density of 6.07 Mg/m3. The reversible temperature coefficient of Jr was ,(Jr)=,0.04%/°C and the temperature coefficient of HcJ in the range from 25°C to 125°C obtained by linear extrapolation was ,(HcJ)=,0.40%/°C. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(7): 25,31, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10124 [source] Survival and oviposition of a western corn rootworm variant feeding on soybeanENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2003Timothy R. Mabry Abstract The role of soybean, Glycine max (L.) Merril (Fabaceae), in the circumvention of crop rotation was evaluated by observing the effects of soybean herbivory on western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) survival and oviposition. Field collected D. virgifera adults resistant to annual rotation of corn, Zea mays (L.) (Poaceae), and soybean were given the opportunity to feed on a soybean pre-treatment diet prior to diet combinations of corn, soybean, and/or water. The number of days that the adults survived after removal of the diet combinations was used as a measure of insect vigor and diet quality. Willingness to feed on a soybean foliage pre-treatment did not indicate greater ability to benefit nutritionally from soybean herbivory. Adult D. virgifera previously feeding on corn, soybean, or water survived starvation for 8.3 ± 0.15 days, 5.1 ± 0.13 days, and 3.9 ± 0.14 days, respectively. Diabrotica virgifera recover from 2 days of starvation or poor diet if subsequently given access to corn tissues for 2 days. Eggs were laid within 1 day of access to poor diet or starvation. Other D. virgifera, captured as they flew from a cornfield into a soybean field, were maintained on soybean foliage or only water until they died. Of the beetles with access to soybean foliage, 24% fed within 24 h after capture and survived 1 day longer than insects given only water. Only 20% of these D. virgifera were able to lay eggs without consuming additional corn prior to death. Few D. virgifera enter soybean fields capable of immediate oviposition. Female reproductive status and diet quality influence the likelihood of oviposition following exposure to stress. The effects of soybean herbivory may contribute to the proximate mechanism of resistance to crop rotation. [source] Bacterial energetics, stoichiometry, and kinetic modeling of 2,4-Dinitrotoluene biodegradation in a batch respirometerENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2004Chunlong Zhang Abstract A stoichiometric equation and kinetic model were developed and validated using experimental data from batch respirometer studies on the biodegradation of 2,4-dinitrotoluene (DNT). The stoichiometric equation integrates bacterial energetics and is revised from that in a previous study by including the mass balance of phosphorus (P) in the biomass. Stoichiometric results on O2 consumption, CO2 evolution, and nitrite evolution are in good agreement with respirometer data. However, the optimal P requirement is significantly higher than the stoichiometrically derived P, implying potentially limited bioavailability of P and the need for buffering capacity in the media to mitigate the adverse pH effect for optimal growth of DNT-degrading bacteria. An array of models was evaluated to fit the O2/CO2 data acquired experimentally and the DNT depletion data calculated from derived stoichiometric coefficients and cell yield. The deterministic, integrated Monod model provides the goodness of fit to the test data on DNT depletion, and the Monod model parameters (Ks, X0, ,max, and Y) were estimated by nonlinear regression. Further analyses with an equilibrium model (MINTEQ) indicate the interrelated nature of medium chemical compositions in controlling the rate and extent of DNT biodegradation. Results from the present batch respirometer study help to unravel some key factors in controlling DNT biodegradation in complex remediation systems, in particular the interactions between acidogenic DNT bacteria and various parameters, including pH and P, the latter of which could serve as a nutrient, a buffer, and a controlling factor on the bioavailable fractions of minerals (Ca, Fe, Zn, and Mo) in the medium. [source] An investigation of the relationship between race performance and superficial digital flexor tendonitis in the Thoroughbred racehorseEQUINE VETERINARY JOURNAL, Issue 4 2010B. O'MEARA Summary Reasons for performing study: There is limited information regarding the number of races and the period for evaluation of outcome which is critical for assessment of SDF tendonitis treatments. Objective: To evaluate the re-injury rate and racing performance of Thoroughbred racehorses that sustain SDF tendonitis in relation to matched controls in terms of number of races post treatment and maximum racing performance ratings before and after injury. Study design: Clinical records and racing histories of 401 racehorses with a first occurrence of SDF tendonitis diagnosed by ultrasonography. Controls were of the same age, sex and were horses training in the same establishment at the time of injury as the case horses and where the trainer reported that the horse had not had a previous SDF tendon injury or treatment. Results: Eighty percent of both case and control horses returned to racing after the date of injury, and the re-injury proportion within 3 years of treatment was 53%. The difference in Racing Post Rating(max) (RPR(max)) and the Racing Post Rating in the race immediately before the treatment date was significantly smaller in case horses (mean = 9.6 lbs; range = 0,75) compared to control horses (mean = 17.0 lbs; range = 0,79). No significant decrease in RPR(max) was noted post injury. No difference between case and control horses was found for return to racing and racing 3 times, but control horses were significantly more likely to compete 5 races post treatment date than case horses. Conclusion and clinical relevance: Injury was associated with an individual's pre-injury maximum performance level and return to racing and completion of 3 races are not useful indicator of the outcome of horses with SDF tendonitis. The assessment of the outcome of horses with an SDF injury in a population of racehorses using the number of races post injury requires a minimum of 5 races post injury to be a useful indicator. Further, a re-injury proportion in a population of horses in training for 3 years post treatment. [source] | ||||||||||||||||||||||||||||||||||||||||||||||