bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Zealand Black-Derived Locus Suppresses Chronic Graft-versus-Host Disease and Autoantibody Production through Nonlymphoid Bone Marrow-Derived Cells
Authors: Xu Zhiwei , Vallurupalli Anusha , Fuhrman Christopher , Ostrov David , Morel Laurence 
Published: February 2011

Abstract
The development of lupus pathogenesis results from the integration of susceptibility and resistance genes. We have used a chronic graft-versus-host disease (cGVHD) model to characterize a suppressive locus at the telomeric end of the NZM2410-derived Sle2 susceptibility locus, which we named Sle2c2. cGVHD is induced normally in Sle2c2-expressing mice, but it is not sustained. The analysis of mixed bone marrow chimeras revealed that cGVHD resistance was eliminated by non-B non-T hematopoietic cells expressing the B6 allele, suggesting that resistance is mediated by this same cell type. Furthermore, Sle2c2 expression was associated with an increased number and activation of the CD11b+ GR-1+ subset of granulocytes before and in the early stage of cGVHD induction. We have mapped the Sle2c2 critical interval to a 6-Mb region that contains the Cfs3r gene, which encodes for the G-CSFR, and its NZM2410 allele carries a nonsynonymous mutation. The G-CSFR–G-CSF pathway has been previously implicated in the regulation of GVHD, and our functional data on Sle2c2 suppression suggest a novel regulation of T cell-induced systemic autoimmunity through myeloid-derived suppressor cells. The validation of Csf3r as the causative gene for Sle2c2 and the further characterization of the Sle2c2 MDSCs promise to unveil new mechanisms by which lupus pathogenesis is regulated.
Ly49-Dependent NK Cell Licensing and Effector Inhibition Involve the Same Interaction Site on MHC Ligands
Authors: Choi Taewoong , Ferris Stephen T. , Matsumoto Naoki , Poursine-Laurent Jennifer , Yokoyama Wayne M. 
Published: February 2011

Abstract
NK cells become functionally competent to be triggered by their activation receptors through the interaction of NK cell inhibitory receptors with their cognate self-MHC ligands, an MHC-dependent educational process termed “licensing.” For example, Ly49A+ NK cells become licensed by the interaction of the Ly49A inhibitory receptor with its MHC class I ligand, H2Dd, whereas Ly49C+ NK cells are licensed by H2Kb. Structural studies indicate that the Ly49A inhibitory receptor may interact with two sites, termed site 1 and site 2, on its H2Dd ligand. Site 2 encompasses the α1/α2/α3 domains of the H2Dd H chain and β2-microglobulin (β2m) and is the functional binding site for Ly49A in effector inhibition. Ly49C functionally interacts with a similar site in H2Kb. However, it is currently unknown whether this same site is involved in Ly49A- or Ly49C-dependent licensing. In this study, we produced transgenic C57BL/6 mice expressing wild-type or site 2 mutant H2Dd molecules and studied whether Ly49A+ NK cells are licensed. We also investigated Ly49A- and Ly49C-dependent NK licensing in murine β2m-deficient mice that are transgenic for human β2m, which has species-specific amino acid substitutions in β2m. Our data from these transgenic mice indicate that site 2 on self-MHC is critical for Ly49A- and Ly49C-dependent NK cell licensing. Thus, NK cell licensing through Ly49 involves specific interactions with its MHC ligand that are similar to those involved in effector inhibition.
Jetzt wird es ernst: strukturbasiertes Design von Mdm2/Mdmx‐p53‐Inhibitoren
Authors: Popowicz Grzegorz M. , Dömling Alexander , Holak Tad A. 
Published: February 2011

AbstractDas zelluläre p53‐Protein ist das Bollwerk im Kampf gegen Tumor‐assoziierte DNA‐Schäden. Allgemein auch als “Beschützer des Genoms” bekannt, ist p53 für das Schicksal der Zelle verantwortlich, wenn eine substanzielle DNA‐Schädigung vorliegt. Tumoren können sich nur entwickeln, wenn diese Verteidigungslinie durchbrochen wird. Alle bekannten Tumorzellen mutieren das p53‐Gen oder nutzen interne p53‐Modulatoren, wie die beiden Proteine Mdm2 und Mdmx, um p53 zu desaktivieren. Das Freisetzen von p53 aus den Komplexen mit Mdm2 oder Mdmx sollte daher eine effiziente und nicht gentoxische Krebstherapie ermöglichen. Dank mehrerer Kristallstrukturen von Mdm2/x im Komplex mit p53‐imitierenden Molekülen, sowohl Peptiden als auch niedermolekularen Verbindungen, gab es in den letzten Jahren fundamentale Fortschritte bei der Entwicklung neuer p53‐aktivierender Moleküle. Das Verständnis der Bindungseigenschaften des Liganden ermöglicht die Entwicklung neuer, hoch aktiver und selektiver Wirkstoff‐Kandidaten. Zwei niedermolekulare Verbindungen werden seit Kurzem in klinischen Studien untersucht.
A Markov Chain Monte Carlo comparison of variance estimators for the sampling of particulate mixtures
Authors: Cheng Hao , Geelhoed Bastiaan , Bode Peter 
Published: February 2011

AbstractDuring the sampling of particulate mixtures, samples taken are analyzed for their mass concentration, which generally has non‐zero sample‐to‐sample variance. Bias, variance, and mean squared error (MSE) of a number of variance estimators, derived by Geelhoed, were studied in this article. The Monte Carlo simulation was applied using an observable first‐order Markov Chain with transition probabilities that served as a model for the sample drawing process. Because the bias and variance of a variance estimator could depend on the specific circumstances under which it is applied, Monte Carlo simulation was performed for a wide range of practically relevant scenarios. Using the ‘smallest mean squared error’ as a criterion, an adaptation of an estimator based on a first‐order Taylor linearization of the sample concentration is the best. An estimator based on the Horvitz–Thompson estimator is not practically applicable because of the potentially high MSE for the cases studied. The results indicate that the Poisson estimator leads to a biased estimator for the variance of fundamental sampling error (up to 428% absolute value of relative bias) in case of low levels of grouping and segregation. The uncertainty of the results obtained by the simulations was also addressed and it was found that the results were not significantly affected. The potentials of a recently described other approach are discussed for extending the first‐order Markov Chain described here to account also for higher levels of grouping and segregation. Copyright © 2013 John Wiley & Sons, Ltd.
Induction of Cell–Cell Connections by Using in situ Laser Lithography on a Perfluoroalkyl‐Coated Cultivation Platform
Authors: Okano Kazunori , Yu David , Matsui Ai , Maezawa Yasuyo , Hosokawa Yoichiroh , Kira Atsushi , Matsubara Mie , Liau Ian , Tsubokawa Hiroshi , Masuhara Hiroshi 
Published: February 2011

AbstractThis article describes a novel laser‐directed microfabrication method carried out in aqueous solution for the organization of cell networks on a platform. A femtosecond (fs) laser was applied to a platform culturing PC12, HeLa, or normal human astrocyte (NHA) cells to manipulate them and to facilitate mutual connections. By applying an fs‐laser‐induced impulsive force, cells were detached from their original location on the plate, and translocated onto microfabricated cell‐adhesive domains that were surrounded with a cell‐repellent perfluoroalkyl (Rf) polymer. Then the fs‐laser pulse‐train was applied to the Rf polymer surface to modify the cell‐repellent surface, and to make cell‐adhesive channels of several μm in width between each cell‐adhesive domain. PC12 cells elongated along the channels and made contact with others cells. HeLa and NHA cells also migrated along the channels and connected to the other cells. Surface analysis by X‐ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) confirmed that the Rf polymer was partially decomposed. The method presented here could contribute not only to the study of developing networks of neuronal, glial, and capillary cells, but also to the quantitative analysis of nerve function.
The Stability of Cα Peptide Radicals: Why Glycyl Radical Enzymes?
Authors: Hioe Johnny , Savasci Gökcen , Brand Harald , Zipse Hendrik 
Published: February 2011

AbstractThe conformational space of dipeptide models derived from glycine, alanine, phenylalanine, proline, tyrosine, and cysteine has been searched extensively and compared with the corresponding Cα dipeptide radicals at the G3(MP2)‐RAD level of theory. The results indicate that the (least‐substituted) glycine dipeptide radical is the thermochemically most stable of these species. Analysis of the structural parameters indicates that this is due to repulsive interactions between the Cα substituents and peptide units in the radical. A comparison of the conformational preferences of dipeptide radicals and their closed‐shell parents also indicates that radical stability is a strongly conformation‐dependent property.
The settling behavior of uranium trioxide‐water slurries
Authors: Boyd A. W. , Whitton J. L. 
Published: February 2011

AbstractMeasurements have been made of the settling rates of uranium trioxide‐water slurries in the range of 100 to 800 grams per litre at temperatures of 25° and 53°C. The applicability of several equations proposed by others to relate the rate of hindered settling to surface area, concentration and viscosity has been examined. It is shown that the data are best fitted by an empirical equation similar to one proposed by Allison and Murray for zinc, aluminum and magnesium oxide suspensions.
Solar energy: Economics and engineering research at the university of Wisconsin
Authors: Duffie J. A. , Löf G. O. G. 
Published: February 2011

AbstractThe use of solar energy, in most applications, is dependent primarily on economic considerations; solar energy can become an important energy source when the costs of its use become competitive with the costs of energy from other sources. The basic and usually most costly item of equipment for solar energy utilization is the collector, or solar heat exchanger, and the amortization of the first cost of this and associated equipment is the major cost of solar energy. In this paper, the probable economic feasibility of several solar applications is assessed by using the costs of energy from present sources as a basis for estimating upper limits on the first cost of solar heat exchangers and their associated equipment. For example, for space heating in temperate climates, heat exchanger costs would have to be in the range of $1–6 for solar heating to be competitive; this appears to be within an attainable range. Economic considerations have helped shape the development of the Wisconsin solar energy program, and studies of solar heat exchangers and their application to heating, cooling and power generation are briefly described.
A radioactive tracer technique for particle velocity measurement in solids‐gas systems
Authors: Gauvin W. H. , Pasternak I. S. , Torobin L. B. , Yaffe L. 
Published: February 2011

AbstractTo record the velocity history of a particle in complex problems of solid‐gas flow with greater accuracy than is possible with existing methods, a technique was developed which in essence consists of following the flight of the particle under test—which has been previously tagged with a suitable gamma‐emitting nuclide—by means of Geiger probes placed at predetermined points along the outside surface of the duct or reactor and parallel to its axis. Sharp timing pulses are thus obtained on the screen of a cathode‐ray oscilloscope, which permit the estimation of the time elapsed between probe stations to less than 1/1000 second. Complete description of the electronic aspects of the method is given, and details of the particle preparation are outlined.A brief description is given of the application of the method to the determination of the rate of mass and heat transfer from particles in accelerated motion in a turbulent co‐current gas stream and to the study of the effects of the turbulent flow parameters on the drag coefficients of particles in highly turbulent fields.
Thermodynamic properties of some organic compounds: I. PVT relationships and calculated thermodynamic properties for normal butanol
Authors: Shemilt L. W. , Esplen R. W. , Mann R. Singh 
Published: February 2011

AbstractPressure‐volume‐temperature measurements on n‐butanol have been carried out using the Kay type of pressure‐block apparatus and glass capillary cell. Determinations were made isothermally in the saturated vapor and liquid and superheated vapor regions to above the critical point. Compressibility factors have been calculated. Constants in the Beattie‐Bridgman equation of state have been determined from 250° to 300° C. at pressures up to 75 atmospheres.The thermodynamic properties of normal butanol have been calculated over a temperature range of 0°C. to 300°C. and at pressures up to 1000 lb./sq. in. abs. from the PVT data. Values for the saturated liquid, saturated vapor, and superheated vapor are presented on a pressure‐enthalpy diagram with specific volume and entropy as parameters. The entropy of the saturated vapor increases with temperature over a considerable region, indicating a positive specific heat of the saturated vapor in contrast to the lower alcohols of the same series.
Graphical‐numerical determination of variable diffusion coefficient in solids
Authors: Hall Raymond C. 
Published: February 2011

AbstractConsiderable gain in information in characteristics of diffusion coefficient may be obtained if data are analysed for variable diffusion coefficient instead of for a constant value of diffusivity. This paper presents a simple method for graphical analysis of concentration gradients in solids to determine the diffusion coefficient as a function of concentration.Consideration is given to problems encountered in extrapolation of data. It is shown that, if relative values of diffusion coefficient is the objects of consideration, no great need exists for exacting extrapolation. Two extrapolations are employed on any given functional model; the results of one extrapolation are greater, while those of the other arc less than the results predicted by the model.
The efficiency of fibrous aerosol filters: Deposition by diffusion of particles of finite diameter
Authors: Pasceri Ralph E. , Friedlander S. K. 
Published: February 2011

AbstractA brief review is given of the derivation of a semi‐theoretical expression for the filtration efficiency of fibrous aerosol filters operated at low velocities. The correlation is compared with new data taken from the literature and is presented in a simplified form for design calculations. The existence of a minimum filtration efficiency is discussed and theory and data are compared.
Some rheological parameters of clays and their thixotropic behavior
Authors: Yalcin A. S. , McIntosh R. 
Published: February 2011

AbstractRheological characteristics and thixotropic behavior of four clay minerals belonging to different types of morphology and lattice structure were investigated.Clay‐water samples were prepared at about their liquid limits and the testing was accomplished by unconfined compression applied at different rates of deformation.From the stress to strain rate relationships the yield value was determined as an intercept on the stress axis at zero rate of strain, and the slope gave the viscosity coefficient.Regain of strength or thixotropic character of the samples was evaluated in terms of the viscosity and yield values at various periods of aging.The influence of temperature on the aging process was studied using attapulgite at three temperatures, 21°C., 36°C., 51°C.The activation energy of the process of aging for attapulgite was calculated using both viscosity coefficients and ultimate yields. The values were within experimental uncertainty for the two sets of data and it was thereby concluded that changes of these parameters were due to a single reaction. The activation energy was found to be 9.4 kcal mole−1, which suggests a physical rather than a chemical change.
An apparatus for the measurements of light transmittance of emulsions
Authors: Cengel J́. A. , Knudsen J. G. , Landsberg A. , Faruqui A. A. 
Published: February 2011

AbstractThis paper describes an apparatus for the measurement of the light transmittance of emulsions. A photoelectric technique was employed to determine the effect of flow rate, mixing time, and dispersed phase concentration on the light transmittance of a liquid‐liquid emulsion composed of a commercial petroleum solvent and water. For a given concentration, light transmittance was independent of flow rate and became constant after 10 minutes of mixing in the test apparatus. Light transmittance decreased with solvent (dispersed phase) concentration. Up to 5% solvent concentration, the light transmittance‐concentration curve could be used to measure solvent concentration accurately.
Determination of vapor‐liquid equilibrium data from total pressure‐liquid composition measurements
Authors: Ho James C. K. , Boshko O. , Lu Benjamin C.‐Y. 
Published: February 2011

AbstractDigital computer methods are developed for evaluating equilibrium data from total pressure‐liquid composition measurements of volatile binary non‐electrolyte mixtures. The Redlich‐Kister equation is employed for representing liquid activity coefficients. The constants B, C and D are evaluated by the method of least squares for non‐linear formulas. Equilibrium vapor compositions are also evaluated by means of a step‐wise integration procedure. A comparison of both methods is presented.
Treatment of uranium leach plant solutions by liquid‐liquid extraction to produce high purity uranium products
Authors: Simard R. , Gilmore A. J. , McNamara V. M. , Parsons H. W. , Smith H. W. 
Published: February 2011

AbstractThree liquid‐liquid extraction processes were tested in continuous equipment, on bench scale, to determine their relative merits in the purification of uranium as found in ion exchange eluates of various Canadian leach plants. Tri‐n‐butyl phosphate and dibutyl butylphosphonate were used as extractants on nitrate eluates. A tertiary amine was used in the case of sulphuric acid eluates. Optimum conditions for high recovery and low reagent costs were established, and the adaptability of the processes to existing leach plants is discussed. The suitability of the ammonium diuranate product as a source of ceramic‐grade UO2 was also investigated. Suggested changes to the adopted flowsheets are given, for further testing on a pilot plant scale.
Possible applications of various reduction processes to canadian iron ores
Authors: Rogers R. R. , Viens G. E. , Campbell R. A. 
Published: February 2011

AbstractA survey is made of (1) the factors which make possible a Canadian iron production industry, and (2) a number of the iron reduction processes which are now available, and their requirements. Based on this information an attemps is made to forecast the general nature of the Canadian iron production industry in the foreseeable future.
Horizontal annular‐mist flow of natural gas‐water mixtures
Authors: Aziz K. , Govier G. W. 
Published: February 2011

AbstractA survey of the literature having possible application to the annular‐mist flow problem is presented.The horizontal annular‐mist flow of natural gaswater mixtures in one‐ and two‐in. diameter, schedule 40 aluminum pipes was investigated. The input gasliquid volume ratios were varied between 10 and 100,000 for superficial gas velocities between 25 and 300 ft./sec. The mid‐point pressure was held constant at 120 p.s.i.g. Some data for variable mid‐point pressure and constant liquid and gas rates are also presented to show the effect of gas density.The pressure drop data for constant mid‐point density are presented as a function of the superficial velocities of the two phases. The same data are also presented in terms of the ratio of the two‐phase pressure gradient to the single‐phase gas pressure gradient. Possible mechanisms of the flow in the annular‐mist region are discussed and the possibility of microscopic changes in flow pattern is indicated. A large effect of a small quantity of water was observed over the gas rates investigated. Higher water rates had much greater effect at low gas rates than at high gas rates. It is proposed that the high pressure drop is caused by the formation of a liquid film on the inside wall of the pipe. The thickness of this film decreases as the gas rate is increased until it reaches some minimum value. The breakup of this film was not indicated over the range of gas rates investigated.The data are also interpreted in terms of a friction factor and Reynolds number based on the mixture properties.The data are compared with the correlations of Lockhart and Martinelli, and Chenoweth and Martin.
A study of the flotation characteristics of galena
Authors: Nagy E. , Van Cleave A. B. 
Published: February 2011

AbstractA modified Hallimond tube technique has been used to obtain information on the flotation characteristics of galena. The technique has general application to 1 to 2 gram samples of any relatively pure mineral. The influences of stirring rate, gas flow rate, flotation time, pH, particle size, xanthate chain length, and collector concentration have been measured and correlations between some of these factors discussed. The effect of high xanthate concentration on flotation rate has been studied in some detail and discussed in relation to the adsorption of the collector on the mineral.
An analysis of spray evaporation in a high‐temperature environment: II. Calculation of the evaporative load distribution
Authors: Hoffman T. W. , Gauvin W. H. 
Published: February 2011

AbstractThis paper deals with the calculation of the evaporative load distribution in a spray of droplets suspended in an absorbing gas medium contained in a cylindrical column after a temperature profile for the gas has been assumed.Preliminary experimental data obtained for water sprays in an 8‐in. i.d. by 10‐ft. high pilot‐plant atomized suspension reactor at wall temperatures up to 800°C. are used to illustrate the method of calculation.The calculated results emphasize the importance of the physical characteristics of the spray, such as initial drop‐size and distribution, drop velocities and spray angle. They also indicate that the dynamics of such spray systems, as well as their heat and mass transfer aspects, require further elaboration.
Mass transfer from fluid and solid spheres at low Reynolds numbers: Part II
Authors: Ward D. M. , Trass O. , Johnson A. I. 
Published: February 2011

AbstractRates of mass transfer from water drops into cyclohexanol and from drops of cyclohexanol, isobutanol, and o‐toluidine into water were measured. These experimental data were augmented by published results, to cover, at drop Reynolds numbers less than 10, a Peelet number range of 0.01 to 5,000,000 for non‐circulating spheres and 700 to 24,000,000 for circulating spheres. Transfer rates, expressed as Sherwood numbers, were in substantial agreement with those predicted from a theoretical model. The contribution of natural convection, inherent in the measurements, but omitted in the model, was approximately accounted for. Data for circulating spheres verified the hypothesis that internal motion affects the external transfer rate. This effect depends on the ratio of continuous to disperse phase viscosity of the system; a four to six‐fold enhancement of mass transfer due to internal circulation was found for water drops falling in cyclohexanol.