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Multiplicity
Kinds of Multiplicity Selected AbstractsEXPENDING MULTIPLICITY: MONEY IN CUBAN IFÁ CULTSTHE JOURNAL OF THE ROYAL ANTHROPOLOGICAL INSTITUTE, Issue 2 2005Martin Holbraad Countering the assumption that money acts as an agent of abstraction and ,disembedment', anthropologists tend to draw money into analogies with other objects of exchange, downplaying its uniquely quantitative nature. This article seeks to disentangle the association, implicit in this tendency, of quantity with abstraction. Focusing on the peculiar character of money as a ,purely multiple' object, the aim is to account for ,embeddedness' without bracketing quantity: what does quantity look like when it is not viewed as an abstract denominator? The question is explored with reference to Ifá, an Afro-Cuban diviner cult that takes monetary transactions as a cosmological premise. [source] Decolonising, Multiplicities and Mining in the Eastern Goldfields, Western AustraliaGEOGRAPHICAL RESEARCH, Issue 1 2003Leah M. Gibbs In this ,postcolonial' era, peoples and places around the globe continue to face ongoing colonisation. Indigenous peoples in particular experience colonisation in numerous forms. Despite recent attempts to ,decolonise' indigenous spaces, hegemonic systems of production, governance and thinking often perpetuate colonial structures and relationships, resulting in further entrenched colonisation or ,deep colonising' (Rose, 1999). The interface between indigenous communities and the mining industry provides fertile ground for the tensions emerging between decolonising and deep colonising. Gold mining operations at Placer Dome's Granny Smith mine in the Eastern Goldfields of Western Australia present a valuable case study for examining this tension. Changes taking place at the mine site are decolonising in intent, though outcomes may be deep colonising in effect. Recent discussions among cultural geographers over meanings of place, Ollman's (1993) notion of vantage point and a broadly postcolonial literature inform consideration of this tension. Acknowledgment and incorporation of multiple vantage points into new resource management systems allows current hegemonic approaches to be rethought, and provides insights for the shift towards genuinely decolonising processes. [source] The difficult and ubiquitous problems of multiplicitiesPHARMACEUTICAL STATISTICS: THE JOURNAL OF APPLIED STATISTICS IN THE PHARMACEUTICAL INDUSTRY, Issue 3 2007Donald A. Berry Abstract Multiplicities are ubiquitous. They threaten every inference in every aspect of life. Despite the focus in statistics on multiplicities, statisticians underestimate their importance. One reason is that the focus is on methodology for known multiplicities. Silent multiplicities are much more important and they are insidious. Both frequentists and Bayesians have important contributions to make regarding problems of multiplicities. But neither group has an inside track. Frequentists and Bayesians working together is a promising way of making inroads into this knotty set of problems. Two experiments with identical results may well lead to very different statistical conclusions. So we will never be able to use a software package with default settings to resolve all problems of multiplicities. Every problem has unique aspects. And all problems require understanding the substantive area of application. Copyright © 2007 John Wiley & Sons, Ltd. [source] Accounting for Multiplicities in Assessing Drug Safety: A Three-Level Hierarchical Mixture ModelBIOMETRICS, Issue 2 2004Scott M. Berry Summary. Multiple comparisons and other multiplicities are among the most difficult of problems that face statisticians, frequentists, and Bayesians alike. An example is the analysis of the many types of adverse events (AEs) that are recorded in drug clinical trials. We propose a three-level hierarchical mixed model. The most basic level is type of AE. The second level is body system, each of which contains a number of types of possibly related AEs. The highest level is the collection of all body systems. Our analysis allows for borrowing across body systems, but there is greater potential,depending on the actual data,for borrowing within each body system. The probability that a drug has caused a type of AE is greater if its rate is elevated for several types of AEs within the same body system than if the AEs with elevated rates were in different body systems. We give examples to illustrate our method and we describe its application to other types of problems. [source] SESAME-HSQC for simultaneous measurement of NH and CH scalar and residual dipolar couplings,MAGNETIC RESONANCE IN CHEMISTRY, Issue 4 2007Peter Würtz Abstract We present a novel pulse sequence, SESAME-HSQC, for the simultaneous measurement of several NH and CH scalar and residual dipolar couplings in double labeled proteins. The proposed Spin-statE Selective All Multiplicity Edited (SESAME)-HSQC combines gradient selected and sensitivity enhanced 15N- and constant-time 13C-HSQC experiments with the recently introduced spin-state selective method (Nolis et al., J. Magn. Reson. 180 (2006) 39,50) for measuring couplings simultaneously at amide and aliphatic regions. Excellent resolution and high sensitivity is warranted by removing all coupling interactions during the indirectly detected t1 period, and by employing pulsed field gradients for coherence selection and utilizing coherence order selective spin-state selection. The scalar and residual dipolar couplings can be readily measured from a two-dimensional 15N/13C-HSQC spectrum without additional spectral crowding. SESAME-HSQC can be used for epitope mapping by observing chemical shift changes in both amide and aliphatic regions. Simultaneously, potential conversion in protein conformation can be probed by analyzing changes in residual dipolar couplings induced by ligand binding. The pulse sequence is experimentally verified with a sample of 15N/13C enriched human ubiquitin. The internuclear vector directions determined from the residual dipolar couplings are found to be in excellent correlation with those predicted from ubiquitin's refined solution structure. Copyright © 2007 John Wiley & Sons, Ltd. [source] Beyond Monotheism: A Theology of Multiplicity , By Laurel C. SchneiderRELIGIOUS STUDIES REVIEW, Issue 4 2008Michelle Voss Roberts No abstract is available for this article. [source] Distinguishing Effects on Tumor Multiplicity and Growth Rate in Chemoprevention ExperimentsBIOMETRICS, Issue 4 2000David B. Dunson Summary. In some types of cancer chemoprevention experiments and short-term carcinogenicity bioassays, the data consist of the number of observed tumors per animal and the times at which these tumors were first detected. In such studies, there is interest in distinguishing between treatment effects on the number of tumors induced by a known carcinogen and treatment effects on the tumor growth rate. Since animals may die before all induced tumors reach a detectable size, separation of these effects can be difficult. This paper describes a flexible parametric model for data of this type. Under our model, the tumor detection times are realizations of a delayed Poisson process that is characterized by the age-specific tumor induction rate and a random latency interval between tumor induction and detection. The model accommodates distinct treatment and animal-specific effects on the number of induced tumors (multiplicity) and the time to tumor detection (growth rate). A Gibbs sampler is developed for estimation of the posterior distributions of the parameters. The methods are illustrated through application to data from a breast cancer chemoprevention experiment. [source] The variation of the galaxy luminosity function with group propertiesMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2010Aaron Robotham ABSTRACT We explore the shape of the galaxy luminosity function (LF) in groups of different mass by creating composite LFs over large numbers of groups. Following previous work using total group luminosity as the mass indicator, here we split our groups by multiplicity and by estimated virial (group halo) mass, and consider red (passive) and blue (star-forming) galaxies separately. In addition, we utilize two different group catalogues (2PIGG and Yang et al.) in order to ascertain the impact of the specific grouping algorithm and further investigate the environmental effects via variations in the LF with position in groups. Our main results are that LFs show a steepening faint end for early-type galaxies as a function of group mass/multiplicity, with a much suppressed trend (evident only in high mass groups) for late-type galaxies. Variations between LFs as a function of group mass are robust irrespective of which grouping catalogue is used, and broadly speaking what method for determining group ,mass' is used. We find in particular that there is a significant deficit of low-mass passive galaxies in low-multiplicity groups, as seen in high-redshift clusters. Further to this, the variation in the LF appears to only occur in the central regions of systems, and in fact seems to be most strongly dependent on the position in the group relative to the virial radius. Finally, distance,rank magnitude relations were considered. Only the Yang groups demonstrated any evidence of a correlation between a galaxy's position relative to the brightest group member and its luminosity. 2PIGG possessed no such gradient, the conclusion being the friend-of-friend algorithm suppresses the signal for weak luminosity,position trends and the Yang grouping algorithm naturally enhances it. [source] Polycationic States of Oligoanilines Based on Wurster's BlueEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 26 2009Akihiro Ito Abstract Polycations of two oligoanilines based on Wurster's blue,N,N,,N, -tris[4-(dimethylamino)phenyl]- N,N,,N, -trimethyl-1,3,5-benzenetriamine (2) and N,N, -bis(3-{N -[4-(dimethylamino)phenyl]- N -methylamino}phenyl)- N,N, -dimethyl- p -phenylenediamine (3), have been generated efficiently by a stepwise oxidation procedure. Their redox behavior was characterized in terms of the embedded p -phenylenediamine (PD) units and their intramolecular connectivity. EPR analysis of the oxidized 2 and 3 species revealed the existence of high-spin species in solution. It was found that spin multiplicities of the dominant polycationic species of 2 and 3 formed by 3 equiv. of oxidant can be assigned to quartet and doublet states, respectively on the basis of pulsed EPR spectroscopy. These results demonstrate that the intramolecular connectivity between the spin-containing units decisively influences the spin preference of the multispin systems based on oligoanilines.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Advancing beyond charge analysis using the electronic localization function: Chemically intuitive distribution of electrostatic momentsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 9 2008Julien Pilmé Abstract We propose here an evaluation of chemically intuitive distributed electrostatic moments using the topological analysis of the electron localization function (ELF). As this partition of the total charge density provides an accurate representation of the molecular dipole, the distributed electrostatic moments based on the ELF partition (DEMEP) allows computing of local moments located at non atomic centers such as lone pairs, , bonds and , systems. As the local dipole contribution can be decomposed in polarization and charge transfer components, our results indicate that local dipolar polarization of the lone pairs and chemical reactivity are closely related whereas the charge transfer contribution is the key factor driving the local bond dipole. Results on relevant molecules show that local dipole contributions can be used to rationalize inductive polarization effects in alcohols derivatives and typical hydrogen bond interactions. Moreover, bond quadrupole polarization moments being related to a , character enable to discuss bond multiplicities, and to sort families of molecules according to their bond order. That way, the nature of the CO bond has been revisited for several typical systems by means of the DEMEP analysis which appears also helpful to discuss aromaticity. Special attention has been given to the carbon monoxide molecule, to the CuCO complex and to a weak intramolecular N|---CO interaction involved in several biological systems. In this latter case, it is confirmed that the bond formation is mainly linked to the CO bond polarization. Transferability tests show that the approach is suitable for the design of advanced force fields. © 2008 Wiley Periodicals, Inc. J Comput Chem 2008 [source] All CVB serotypes and clinical isolates induce irreversible cytopathic effects in primary cardiomyocytesJOURNAL OF MEDICAL VIROLOGY, Issue 2 2005Jeonghyun Ahn Abstract Coxsackievirus B3 (CVB3) has been identified as a major causative agent of acute and chronic myocarditis, but the involvement of other CVB serotypes in myocarditis has not been investigated. To dissect the pathological properties of different CVB serotypes toward primary cardiomyocytes, we tested their effects on primary cardiomyocyte cultures from neonatal rats. Morphological abnormalities were examined by both light and fluorescence microscopy after Hoechst 33342 staining, and loss of cell viability was estimated by MTT assay. All six CVB serotypes showed a similar degree of severe toxicity toward primary cardiomyocytes. CVB clinical isolates had cytopathic effects (CPEs) similar to those of their respective CVB reference strains. Within 1,2 days of infection with multiplicities of infection MOI 50, the cells began to experience morphological changes including cell shrinkage, rounding-up, and slight nuclear condensation. The irreversible loss of cell viability was readily observed within 3,5 days following virus infection. These results suggest that all six CVB serotypes induce direct, irreversible toxicity towards cardiomyocytes, which eventually leads to the death of infected cells. These findings indicate that the variations in CVB serotype are not the limiting factor determining the susceptibility of cardiomyocytes to CVB infection. J. Med. Virol. 75:290,294, 2005. © 2004 Wiley-Liss, Inc. [source] Porphyromonas gingivalis stimulates the release of nitric oxide by inducing expression of inducible nitric oxide synthases and inhibiting endothelial nitric oxide synthasesJOURNAL OF PERIODONTAL RESEARCH, Issue 3 2010W. Sun Sun W, Wu J, Lin L, Huang Y, Chen Q, Ji Y. Porphyromonas gingivalis stimulates the release of nitric oxide by inducing expression of inducible nitric oxide synthases and inhibiting endothelial nitric oxide synthases. J Periodont Res 2010; 45: 381,388. © 2010 The Authors. Journal compilation © 2010 Blackwell Munksgaard Background and Objective:, The purpose of this study was to examine the ability of Porphyromonas gingivalis to invade human umbilical vein endothelial cells (HUVECs) and to study the effects of P. gingivalis ATCC 33277 on the production of nitric oxide (NO) and on the expression of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) in HUVECs. We attempted to throw light on the pathway of damage to endothelial function induced by P. gingivalis ATCC 33277. Material and Methods:,P. gingivalis ATCC 33277 was cultured anaerobically, and HUVECs were treated with P. gingivalis ATCC 33277 at multiplicities of infection of 1:10 or 1:100 for 4, 8, 12 and 24 h. HUVECs were observed using an inverted microscope and transmission electron microscopy. NO production was assayed through measuring the accumulation of nitrite in culture supernatants. Expression of both iNOS and eNOS proteins was investigated through western blotting. Results:, It was found that P. gingivalis ATCC 33277 can adhere to HUVECs by fimbriae, invade into HUVECs and exist in the cytoplasm and vacuoles. P. gingivalis ATCC 33277 can induce iNOS and inhibit eNOS expression, and stimulate the release of NO without any additional stimulant. Conclusion:, Our study provides evidence that P. gingivalis ATCC 33277 can invade HUVECs, and the ability of P. gingivalis ATCC 33277 to promote the production of NO may be important in endothelial dysfunction, suggesting that P. gingivalis ATCC 33277may be one of the pathogens responsible for atherosclerosis. [source] Multiple steady states in distillation: Effect of VL(L)E inaccuraciesAICHE JOURNAL, Issue 5 2000Nikolaos Bekiaris Output multiplicities in heterogeneous azeotropic distillation columns were studied. The accuracy of the thermodynamic description is a key factor that determines if multiplicities can be observed in numerical simulations. The descriptions used in the multiplicity-related literature are analyzed. The ,/, analysis of Bekiaris et al. (1996) was used to check implications of inaccuracies in the reported thermodynamics on the existence of multiplicities in azeotropic distillation. On this basis, guidelines are derived concerning what features of thermodynamic descriptions need special attention for use in multiplicity prediction and simulation. Secondly, numerical studies on output multiplicities in heterogeneous azeotropic distillation in the literature were compared to the ,/, predictions wherever possible. The ,/, analysis was used to derive the relations between the reported multiplicities and to identify the physical phenomena causing them. [source] NMR Characterization of Carbazole-Substituted Norbornene Comonomer 9-(Bicyclo[2.2.1.]hept-5-en-2-ylmethyl)-9H -carbazole (BHMCZ) and Poly(ethylene- co -BHMCZ) CopolymerMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 3 2003Ilpo Mustonen Abstract Carbazole-substituted norbornene comonomer 9-(bicyclo[2.2.1.]hept-5-en-2-ylmethyl)-9H -carbazole (BHMCZ) can be copolymerized with ethylene using the [Ph2C(Ind)(Cp)ZrCl2] catalyst and methylaluminoxane (MAO) cocatalyst system. The microstructures of BHMCZ comonomer and of ethylene,BHMCZ copolymer containing 4.6 mol-% BHMCZ units in the chain were characterized by one-dimensional 13C DEPT and two-dimensional homonuclear 1H- 1H COSY and heteronuclear 1H- 13C HXCO NMR spectroscopy. The BHMCZ comonomer appears as endo and exo stereoisomers, which were identified on the basis of chemical shifts, signal multiplicities, and coupling in the 2D NMR spectra. The NMR information on the BHMCZ isomers was used to assist in the determination of the chemical shifts and microstructure of ethylene,BHMCZ copolymer. The NMR analysis of ethylene,BHMCZ copolymer indicated that exo -BHMCZ polymerizes with ethylene slightly more readily than does endo -BHMCZ under the polymerization conditions employed. Isolated segments of exo(2)- exo(5)- exo(6) and endo(2)- exo(5)- exo(6) ethylene-BHMCZ copolymer showing carbon atom numbering. [source] Lactate isotopomer analysis by 1H NMR spectroscopy: Consideration of long-range nuclear spin,spin interactionsMAGNETIC RESONANCE IN MEDICINE, Issue 6 2004Steven G. Lloyd Abstract Lactate is a key metabolite and its rates of cellular uptake and release, its production rates from glucose and glycogen, and its interconversion rate with pyruvate are important determinants of cellular energy production. If lactate precursors such as pyruvate and glucose are labeled appropriately with 13C, 1H NMR spectroscopy provides a means of quantifying lactate production from each source and allows measurement of all these rates within a single experiment. However, due to the multiplicities of the resonance lines (from nuclear spin,spin couplings) in lactate 13C isotopomers, the 1H NMR spectra were found to be more complex than expected, requiring determination of all spin,spin interactions in this anion. All such values were determined for lactate and its precursor pyruvate. The method was then applied to simultaneously measure the rates of exogenous lactate uptake and rates of release of glucose-, glycogen-, and pyruvate-derived lactate in the isolated perfused rat heart. Magn Reson Med 51:1279,1282, 2004. © 2004 Wiley-Liss, Inc. [source] Effects of galaxy-halo alignment and adiabatic contraction on gravitational lens statisticsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2008Quinn E. Minor ABSTRACT We study the strong gravitational lens statistics of triaxial cold dark matter haloes occupied by central early-type galaxies. We calculate the image separation distribution for double, cusp and quad configurations. The ratios of image multiplicities at large separations are consistent with the triaxial NFW model, and at small separations are consistent with the singular isothermal ellipsoid model. At all the separations, the total lensing probability is enhanced by adiabatic contraction. If no adiabatic contraction is assumed, naked cusp configurations become dominant at ,2.5 arcsec, which is inconsistent with the data. We also show that at small-to-moderate separations (,5 arcsec) the image multiplicities depend sensitively on the alignment of the shapes of the luminous and dark matter projected density profiles. In contrast to other properties that affect these ratios, the degree of alignment does not have a significant effect on the total lensing probability. These correlations may therefore be constrained by comparing the theoretical image separation distribution to a sufficiently large lens sample from future wide and deep sky surveys such as Pan-Stars, LSST and JDEM. Understanding the correlations in the shapes of galaxies and their dark matter halo is important for future weak lensing surveys. [source] The difficult and ubiquitous problems of multiplicitiesPHARMACEUTICAL STATISTICS: THE JOURNAL OF APPLIED STATISTICS IN THE PHARMACEUTICAL INDUSTRY, Issue 3 2007Donald A. Berry Abstract Multiplicities are ubiquitous. They threaten every inference in every aspect of life. Despite the focus in statistics on multiplicities, statisticians underestimate their importance. One reason is that the focus is on methodology for known multiplicities. Silent multiplicities are much more important and they are insidious. Both frequentists and Bayesians have important contributions to make regarding problems of multiplicities. But neither group has an inside track. Frequentists and Bayesians working together is a promising way of making inroads into this knotty set of problems. Two experiments with identical results may well lead to very different statistical conclusions. So we will never be able to use a software package with default settings to resolve all problems of multiplicities. Every problem has unique aspects. And all problems require understanding the substantive area of application. Copyright © 2007 John Wiley & Sons, Ltd. [source] Radical Cation Generation from Singlet and Triplet Excited States of All-trans-Lycopene in Chloroform,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2004Rui-Min Han ABSTRACT On direct photoexcitation, subpicosecond time-resolved absorption spectroscopy revealed that the 1Bu -type singlet excited state of all- trans -lycopene in chloroform was about seven times more efficient than all-trans-,-carotene in generating the radical cation. The time constant of radical cation generation from the 1Bu -type state was found to be ,0.14 ps, a value that was comparable for the two carotenoids. On anthracene-sensitized triplet excitation, radical cation generation was found to be much less efficient for lycopene than for ,-carotene. A slow rising phase (20-30 ,s) in the bleaching of ground-state absorption was common for both lycopene and ,-carotene in chloroform and was ascribed to an efficient secondary reaction with a solvent radical leading to the formation of carotenoid radical cations. The reverse ordering in the tendency of the excited states of different multiplicities for the two carotenoids to generate radical cations is discussed in relation to the two carotenoids as scavengers of free radicals. [source] Determination of all misorientations of tetragonal lattices with low multiplicity; connection with Mallard's rule of twinningACTA CRYSTALLOGRAPHICA SECTION A, Issue 4 2003Hans Grimmer Two congruent lattices are considered, which are misoriented in such a way that they have a fraction 1, of symmetry translations in common. Whereas for cubic lattices body or face centring does not affect the `multiplicity' or `twin index' ,, this is not generally true for tetragonal lattices. Consider a fixed misorientation and let ,P and ,I be the multiplicities for tP and tI lattices with the same axial ratio ca. Grimmer [Mater. Sci. Forum (1993), 126,128, 269,272] has given an explicit formula for ,P (depending on the misorientation and the axial ratio) and showed that ,I = ,P2, ,P or 2,P. Here stronger results on the occurrence of the three possibilities are presented. Lists of all axial ratios ca of tP and tI lattices admitting misorientations with ,, 5 are given. For each of these misorientations, the twin mirror planes and their normals are listed, so that a synopsis of all possible twin laws of tetragonal crystals by reticular merohedry with ,, 5 is obtained. It is shown that the two twin laws observed in ,-Sn can be described by reticular pseudomerohedry with ,I,=,2 and obliquity ,,=,2.6134°. [source] Growth factors improve gene expression after lentiviral transduction in human adult and fetal hepatocytesTHE JOURNAL OF GENE MEDICINE, Issue 2 2007Clare Selden Abstract Background Lentiviral vectors may be vectors of choice for transducing liver cells; they mediate integration in quiescent cells and offer potential for long-term expression. In adult liver, hepatocytes are generally mitotically quiescent. There has been controversy as to the necessity for lentiviral vector target cells to be in the cell cycle; currently, there is consensus that effective transduction can be achieved in quiescent hepatocytes, by using virus at high titre. However, transduction approaches which reduce the multiplicities of infection (MOIs) required provide potential benefit of cost and safety for therapeutic use. Methods We used two late-generation HIV-based lentiviral vector systems (pHR-SIN-cppT SGW and pRRLSIN.cPPT.PGK.WPRE) encoding LacZ/GFP reporter genes to transduce adult and fetal human hepatocytes in vitro + /, growth factors, hepatocyte growth factor (HGF) and epidermal growth factor (EGF). Green fluorescent protein (GFP) expression was observed microscopically, and quantified by fluorescence spectrometry for protein expression, fluorescence-activated cell sorting (FACS) analysis to identify the proportion of cells expressing GFP, and real-time quantitative polymerase chain reaction (PCR) for number of integrations. Results Gene expression following lentiviral transduction of human liver cells in vitro was markedly enhanced by the growth factors HGF and EGF. In adult cells growth factors led to a greater proportion of cells expressing more GFP per cell, from more integration events. In human fetal cells, the proportion of transduced hepatocytes remained identical, but cells expressed more GFP protein. Conclusions This has implications for the design of regimes for liver cell gene therapy, allowing marked reduction of MOIs, and reducing both cost and risk of viral-mediated toxicity. Copyright © 2007 John Wiley & Sons, Ltd. [source] Dynamic Simulation and Control of an MTBE Catalytic Distillation ColumnASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 3-4 2000H. Lin A dynamic model of an MTBE (methyl tert butyl ether) catalytic distillation column was developed using the SpeedUp simulation package. Experimental kinetic rate data, rigorous thermodynamics, vapour-liquid nonidealities and tray hydraulics were incorporated in the simulation. The steady state results from the dynamic model were compared with the steady state results from a steady state model developed using the AspenPlus simulation package. The steady state results from the two simulations were in perfect agreement with each other. Open hop step tests were performed on the dynamic model of this process and the process model indicated a non-linear, self-regulating behaviour and did not exhibit any multiplicities. Multiloop linear control systems were designed and PI, PID and Dynamic Matrix Control (DMC) controllers were tested on the simulation for load disturbances and setpoint changes. All controllers performed adequately; the DMC controller consistently resulted in better dynamic control performance than the other two controllers. [source] Chemoprevention of lung cancer by lycopeneBIOFACTORS, Issue 1-4 2000Dae Joong Kim Abstract An investigation was conducted to assess the chemopreventive potential of lycopene (LP), a naturally occurring hydrocarbon carotenoid found in tomatoes and their products, administered during the post-initiation stage in a multiorgan carcinogenesis model. One hundred eighteen B6C3F_1 mice of both sexes were subjected to combined treatment with diethylnitrosamine (DEN), N-methyl-N-nitrosourea (MNU) and 1,2-dimethylhydrazine (DMH) from day 11 after birth to week 9 (DMD treatment) (groups 1 and 2) or given their vehicles (group 3). Then group 1 received LP (25 or 50 ppm in drinking water) for 21 weeks from weeks 11 to 32. Group 2 served as a carcinogen alone control and group 3 was given only LP (25 or 50 ppm). The incidences and multiplicities of lung adenomas plus carcinomas combined in male mice in group 1 receiving LP 50 ppm were significantly decreased as compared to the DMD alone or DMD and LP 25 ppm group values (75.0 vs 18.8%, P < 0.02; 0.94 ± 0.17 vs 0.25 ± 0.14, P < 0.001). While hepatocellular carcinomas were lacking in the DMD and LP groups, two cases were found in the DMD alone group (not statistically significant). The values for aberrant crypt foci (ACF) and tumors in the colon and kidney did not show any significant variation among the carcinogen-treated subgroups. The results of this study provide evidence that the tomato carotenoid, lycopene, may have potential as a chemopreventive agent against carcinogenesis in the male lung. [source] Accounting for Multiplicities in Assessing Drug Safety: A Three-Level Hierarchical Mixture ModelBIOMETRICS, Issue 2 2004Scott M. Berry Summary. Multiple comparisons and other multiplicities are among the most difficult of problems that face statisticians, frequentists, and Bayesians alike. An example is the analysis of the many types of adverse events (AEs) that are recorded in drug clinical trials. We propose a three-level hierarchical mixed model. The most basic level is type of AE. The second level is body system, each of which contains a number of types of possibly related AEs. The highest level is the collection of all body systems. Our analysis allows for borrowing across body systems, but there is greater potential,depending on the actual data,for borrowing within each body system. The probability that a drug has caused a type of AE is greater if its rate is elevated for several types of AEs within the same body system than if the AEs with elevated rates were in different body systems. We give examples to illustrate our method and we describe its application to other types of problems. [source] Virus-like particle production at low multiplicities of infection with the baculovirus insect cell systemBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2003Luis Maranga Abstract The baculovirus insect cell expression system (BEVS) was used for the production of self-forming Porcine parvovirus -like particles (VLPs) in serum-free medium. A low multiplicity of infection (MOI) strategy was used to overcome an extra virus amplification step, undesirable in industrial production, and to minimize the virus passage effect. It was confirmed that the time of infection (TOI) and MOI are dependent variables. Higher cell densities were obtained at low MOIs, keeping a constant TOI; however, both volumetric and specific productivities were lower. In synchronous infection, at high MOI, the specific productivity decreased when the cells were infected in the late phase of growth. Product degradation due to cell lysis strongly influenced the optimal time of harvest (TOH). Time of harvest was found to be highly dependent on the MOI, and a direct relationship with the cell yield was obtained. Analysis of the culture medium reveals that glutamine depletion occurs in the late phase of the growth. Supplementation of glutamine to uninfected cell cultures resulted in an increased cell yield. Its addition to cultures infected in the middle phase of the growth curve was also able to restore the productivity levels, but addition to cells in their stationary phase caused no observable effect on product expression. The study clearly shows that for a specific TOI it is not obvious what the correct MOI should be to obtain the best volumetric productivity. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 84: 245,253, 2003. [source] Using the rate of respiration to monitor events in the infection of Escherichia coli cultures by bacteriophage T4BIOTECHNOLOGY PROGRESS, Issue 3 2010Dominic Sauvageau Abstract The growing interest in applications of bacteriophages creates a need for improvements in the production processes. Continuous monitoring of the phage production is an essential aspect of any control strategy and, at present, there is no completely satisfactory option. The approach presented here uses IR-spectrometry to continuously measure the rate of respiration (CO2 released) of Escherichia coli infected by phage T4 at various multiplicities of infection (MOI). Within the trends in these data, or in other aspects of the rate of respiration, it was possible to reliably and reproducibly identify five features that reflected specific events in the infection process. These included two events in the host cell apparent growth rate and events in the magnitude of the host cell density, in the measurement of OD600 or in the specific rate of respiration. All of these correlations were within 95% confidence showing that they are suitable for the monitoring and control of E. coli populations infected by phage T4. This method is reliable, cheap, and can be operated in-line and in real time. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] Exploring multiplicity conditions in enzymatic reaction networksBIOTECHNOLOGY PROGRESS, Issue 3 2009Irene Otero-Muras Abstract In this work, a novel algorithmic approach to detect multiplicity of steady states in enzymatic reaction networks is presented. The method exploits the structural properties of networks derived from the Chemical Reaction Network Theory. In first instance, the space of parameters is divided in different regions according to the qualitative behavior induced by the parameters in the long term dynamics of the network. Once the regions are identified, a condition for the appearance of multiplicities is checked in the different regions by solving a given optimization problem. In this way, the method allows the characterization of the whole parameter space of biochemical networks in terms of the appearance or not of multistability. The approach is illustrated through a well-known case of enzymatic catalysis with substrate inhibition. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Lack of enhancement of susceptibility to mammary and thyroid carcinogenesis in rats exposed to DMBA and DHPN following prepubertal iodine deficiencyCANCER SCIENCE, Issue 10 2006Young-Man Cho Epidemiologic and experimental studies suggest that iodine deficiency increases the risk of mammary as well as thyroid cancers, but susceptibility to tumor development when this occurs during the prepubertal stage is not completely understood. In the present study, we therefore evaluated this question in F344 rats. Dams during the lactation period and their weaned offspring until postnatal week 7 were fed an iodine-free diet. Female offspring were then given 7,12-dimethylbenz[a]anthracene (DMBA, 50 mg/kg body weight) by gavage for mammary tumor induction in week 7. Both the male and female rats were given free access to drinking water containing N -bis(2-hydroxypropyl)nitrosamine (DHPN), (0.1 and 0.2% for male and female rats, respectively) for wide spectrum tumor induction in organs, including the thyroid gland, from weeks 7,11. All offspring were killed at week 50 for histopathological examination. The iodine deficiency had no significant influence on incidences and/or multiplicities of mammary and thyroid tumors. Furthermore, tumor induction in the liver, kidney, lung, esophagus and urinary bladder was not affected in either sex. The present results thus indicate a lack of influence of iodine deficiency condition early in life on subsequent carcinogenic susceptibility. (Cancer Sci 2006; 97: 1031,1036) [source] Renal Carcinogenicity of Concurrently Administered Fish Meal and Sodium Nitrite in F344 RatsCANCER SCIENCE, Issue 2 2000Fumio Furukawa The effects of long-term concurrent administration of powdered fish meal and sodium nitrite were examined in F344 rats. A total of 600, 6-week-old rats were divided into 6 male and 6 female groups, each consisting of 50 animals. Rats in groups 1,3 and 7,9 were respectively fed diets supplemented with 64%, 32% and 8% (basal diet) fish meal, and simultaneously given 0.12% sodium nitrite in their drinking water. Groups 4,6 and 10,12 were respectively given 64%, 32% and 8% fish meal and tap water. At the 104th week, all surviving animals were killed and examined histopathologically. Treatment with fish meal dose-dependently increased the incidences and multiplicities of atypical tubules, adenomas and renal cell carcinomas in sodium nitrite-treated males. Females were less susceptible than males for renal tumor induction. In males given the 64% fish meal diet alone, the incidence and multiplicity of atypical tubules were also significantly increased as compared with the 8% fish meal alone case. Nephropathy was apparent in fish meal-treated groups in a clear dose-dependent manner, irrespective of the sodium nitrite treatment, and was more prominent in males than in females. Dimethylnitrosamine was found in the stomach contents after 4-week treatment with 64% fish meal plus 0.12% sodium nitrite, at a level twice that in the 8% fish meal plus 0.12% sodium nitrite group. The results clearly indicate that concurrent administration of fish meal and sodium nitrite induces renal epithelial tumors. Further studies are required to elucidate how nephropathy and nitrosamines produced in stomach contents may contribute to the observed renal tumor induction. [source] iNOS activity is critical for the clearance of Burkholderia mallei from infected RAW 264.7 murine macrophagesCELLULAR MICROBIOLOGY, Issue 2 2008Paul J. Brett Summary Burkholderia mallei is a facultative intracellular pathogen that can cause fatal disease in animals and humans. To better understand the role of phagocytic cells in the control of infections caused by this organism, studies were initiated to examine the interactions of B. mallei with RAW 264.7 murine macrophages. Utilizing modified kanamycin-protection assays, B. mallei was shown to survive and replicate in RAW 264.7 cells infected at multiplicities of infection (moi) of , 1. In contrast, the organism was efficiently cleared by the macrophages when infected at an moi of 10. Interestingly, studies demonstrated that the monolayers only produced high levels of TNF-,, IL-6, IL-10, GM-CSF, RANTES and IFN-, when infected at an moi of 10. In addition, nitric oxide assays and inducible nitric oxide synthase (iNOS) immunoblot analyses revealed a strong correlation between iNOS activity and clearance of B. mallei from RAW 264.7 cells. Furthermore, treatment of activated macrophages with the iNOS inhibitor, aminoguanidine, inhibited clearance of B. mallei from infected monolayers. Based upon these results, it appears that moi significantly influence the outcome of interactions between B. mallei and murine macrophages and that iNOS activity is critical for the clearance of B. mallei from activated RAW 264.7 cells. [source] Theoretical Design of High-spin Organic Molecules with ,·N,N, as a Spin-containing Fragment and Heterocycles as an End GroupCHINESE JOURNAL OF CHEMISTRY, Issue 11 2006De-Qing Chu Abstract Novel stable high spin molecules possessing three different arranged fashions are designed with ,·N,N< as a spin-containing (SC) fragment, various aromatic, such as benzene (1), pyridine (2), pyridazine (3), pyrimidine (4), pyrazine (5), triazine (6) as end groups (EG) and phenyl as a ferromagnetic coupling (FC) unit. The effects of a different end groups on the spin multiplicities of the ground states and their stabilities were investigated by means of AM1-CI approach. It has been found that the spin densities on the two atoms of the SC fragment are different from delocalization resulting in the specific stability of ,·N,N<. In these molecules, the stabilities of the triplet states decrease when the distance between the atoms of central SC (,N,) increases. The orders of the stability of triplet states for 1an, 1bn, 1cn[They are isomers in which SC is connected with FC in different way (1an, N1NNN1; 1bn, N1N N1N; 1cn, NN1N1N) and six heterocycles are EG] show that the stability of triplet states with heterocycles as end groups is higher than that with phenyl as end groups, and in the order:triazine (EG)>pyrimidine, pyrazine>pyridine, pyridazine. [source] | |||||||||||||||||||||||||||||||||||||