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Fit Better (fit + better)
Selected AbstractsVoltammetric Study of Nitro Radical Anion Generated from Some Nitrofuran Compounds of Pharmacological SignificanceELECTROANALYSIS, Issue 1 2003S. Bollo Abstract The electrochemical behavior of 2-(5-amino- 1,3,4-oxadiazolyl)-5-nitrofuran (NF359) and its comparison with well-known drugs such as nifurtimox (NFX) and nitrofurazone (NFZ) in protic, mixed and aprotic media by cyclic voltammetry, tast and differential pulse polarography was studied. All the compounds were electrochemically reducible in all media being the reduction of the nitrofuran group the main voltammetric signal. The one-electron reduction couple due to the nitro radical anion formation was visualized in mixed (for NF359 and NFZ) and aprotic media (for all compounds). By applying a cyclic voltammetric methodology we have calculated the decay constants (k2) of the corresponding nitro radical anions in mixed and aprotic media. In mixed medium data fit well with a disproportionation reaction of the nitro radical anion but in aprotic medium fit better with a dimerization reaction. Also, considering cyclic voltammetric measurements in aprotic media we have estimated the reduction potential of the RNO2/RNO2., couple in aqueous medium, pH 7 (E17 values) finding very good correlation with E17 values obtained by pulse radiolysis. Furthermore we have calculated the equilibrium constants from the electron transfer from nitro radical anion to oxygen (kO2) finding that nitro radical anion from NF359 is thermodynamically favored to react with oxygen in respect to both NFZ and NFX. [source] Environment,Flexibility Coalignment and Performance: An Analysis in Large versus Small FirmsJOURNAL OF SMALL BUSINESS MANAGEMENT, Issue 3 2006Antonio J. Verdú-Jover This paper takes a wide-ranging transnational look, within the frame of he European Union, at the differences between large and small firms based on practices of flexibility. More specifically, the research aims to evaluate whether small firms form a homogeneous body in applying flexible practices as opposed to large firms, as well as observing the differential effects on performance when there are discrepancies in the coalignment levels between a firm's actual flexibility and that required by the environment. The hypotheses are tested using data from 417 European firms. The results reveal that (1) good coalignments between actual and required flexibility (flexibility fit) have a greater influence on business performance in the case of small firms; (2) there are significant differences between small and large firms as regards operative flexibility, strategic flexibility, financial flexibility (organizational slack), and performance. The large firms analyzed coalign their flexibility fit better in their various dimensions (structural, operative, and strategic); (3) the degree of metaflexibility can be greater among small firms, which represents a greater information processing capacity, thus enabling the flexibility fit to be constantly coaligned to changes in the environment. However, a greater metaflexibility is not immediately reflected in the flexibility fit; and (4) this greater flexibility fit among large firms can be favored by their greater financial flexibility. [source] PROBABILISTIC CHARACTERISTICS OF STRESS CHANGES DURING CEREAL SNACK PUNCTUREJOURNAL OF TEXTURE STUDIES, Issue 2 2007YOSHIKI TSUKAKOSHI ABSTRACT During puncture tests of Japanese cereal snacks, the force increases and decreases alternately. We herein compare the force,deformation curves recorded by two different testing machines and show that the number of changes in the curves depends on the testing machine. Thus, it is impossible to compare results obtained using different instruments. By removing the higher-frequency components of the force,deformation curves, small events are easily missed. The number of large events decreases when lower-frequency components are eliminated. This suggests the importance of providing the information on the frequency range of the testing machines. Nevertheless, the number of large force changes is similar between the examined machines. To model the size,frequency distribution, we selected a parametric probabilistic model from among the Weibull, exponential and Pareto distributions using Akaike information criterion and found that the Weibull or exponential distributions have a fit better than the Pareto distribution. PRACTICAL APPLICATIONS The methods developed in this work can be used to evaluate the quality of crisp snack food. By analyzing the samples obtained from a lot, samples with poor texture because of abnormal moisture levels and/or ingredients can be discerned and can be used to accept or reject the lot. [source] MULTISCALE INFLUENCES ON PHYSICAL AND CHEMICAL STREAM CONDITIONS ACROSS BLUE RIDGE LANDSCAPES,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2002Mark C. Scott ABSTRACT: Streams integrate biogeochemical processes operating at broad to local spatial scales and long term to short term time scales. Humans have extensively altered those processes in North America, with serious consequences for aquatic ecosystems. We collected data on Upper Tennessee River tributaries in North Carolina to: (1) compare landuse and landscape geomorphology with respect to their ability to explain variation in water quality, sedimentation measures, and large woody debris; (2) determine if landscape change over time contributed significantly to explaining present stream conditions; and (3) assess the importance of spatial scale in examining landuse influences on streams. Stream variables were related to both landuse and landscape geomorphology. Forest cover accounted for the most variation in nearly all models, supporting predictions of nutrient enrichment, thermal pollution, and sedimentation caused by landscape disturbance. Legacy effects from past catchment disturbance were apparent in sedimentation measures. Nitrogen and phosphorus concentrations, as well as stream temperature, were lower where riparian buffers had reforested. Models of stream physicochemistry fit better when predictors were catchment wide rather than more localized (i.e., within 2 km of a site). Cumulative impacts to streams due to changes in landuse must be managed from a watershed perspective with quantitative models that integrate across scales. [source] Domains of quality of life and symptoms in male veterans treated for posttraumatic stress disorder,JOURNAL OF TRAUMATIC STRESS, Issue 6 2007Carole A. Lunney This study examined the relationship between domains of quality of life and posttraumatic stress disorder (PTSD) symptoms in 319 male veterans in a randomized trial of group psychotherapy. Confirmatory factor analyses suggested a 4-factor model of quality of life (achievement, self-expression, relationships, and surroundings) fit better than a unidimensional model. Clinically meaningful symptom change was associated with greater change in all quality of life domains. At pretreatment, numbing symptoms uniquely predicted all quality of life domains. Change in avoidance and hyperarousal uniquely predicted change in achievement. Change in reexperiencing uniquely predicted change in self-expression. Change in numbing uniquely predicted change in relationships. Examining change in PTSD symptoms and quality of life domains may provide important information for treatment planning and evaluation. [source] Preparation of bimodal porous copolymer containing ,-cyclodextrin and its inclusion adsorption behaviorJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2010Zhao-Yang Sun Abstract A novel insoluble bimodal porous polymer containing ,-cyclodextrin (,-CD) was prepared to adsorb aromatic amine compound. The process involved copolymerization of styrene and methyl methacrylate with a maleic acid derivative of ,-CD, subsequently, above formed copolymer was foamed by supercritical CO2. The chemical properties and physical structure of obtained copolymer was analyzed using Fourier transform infrared spectra, Thermal gravimetric analysis, X-ray diffraction, scanning electron microscope, and N2 adsorption techniques. The inclusion adsorption of aromatic amine compounds on ,-CD copolymer was carried out in a batch system. The quantities of aromatic amine compounds adsorbed on ,-CD copolymer reached equilibrium within 60 min. The adsorption kinetic could be fitted to a pseudo-second-order kinetic equation, and the linear correlation coefficients varied from 0.9828 to 0.9935. With the influence of molecular structure and hydrophobicity of the aromatic amine compound, the sequence of quantity of aromatic amine compounds adsorbed on ,-CD copolymer is p -toluidine > aniline > benzidine > o -toluidine. The adsorption equilibrium data of aromatic amine compound adsorbed on ,-CD copolymer were fitted to Freundlich and Langmuir models, respectively. The linear correlation coefficients of Langmuir model varied from 0.9516 to 0.9940, and the linear correlation coefficients of Freundlich varied from 0.9752 to 0.9976. It is concluded that Freundlich model fits better than Langmuir model, because the adsorption of aromatic amine compound on ,-CD copolymer is a chemical process. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Investigation of the ELAIS field by Vega photometry: absolute magnitude-dependent Galactic model parametersMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006S. Bilir ABSTRACT We estimate the density laws of the Galactic stellar populations as a function of absolute magnitude in a near-polar Galactic field. The density laws are determined by direct fitting to photometric parallaxes from Vega photometry in the ELAIS field (; epoch 2000), both independently for each population and simultaneously for all stellar populations. Stars have been separated into different populations based on their spatial location. The thick disc and halo are fitted best by an exponential. However, the thin disc is fitted best by using a sech2 law for stars at faint absolute magnitudes [10 < M(g,) , 11, 11 < M(g,) , 12 and 12 < M(g,) , 13], and an exponential law for stars at relatively bright absolute magnitudes [5 < M(g,) , 6, 6 < M(g,) , 7, 7 < M(g,) , 8, 8 < M(g,) , 9 and 9 < M(g,) , 10]. The scaleheights for the sech2 density laws are the equivalent exponential scaleheights. Galactic model parameters are dependent on absolute magnitude. The scaleheight for the thin disc decreases monotonically from stars at bright absolute magnitudes [M(g,) = 5] to stars at faint absolute magnitudes [M(g,) = 13] in the range 363,163 pc, except for the minimum H= 211 pc at 9 < M(g,) , 10 where the sech density law fits better. Its local density is flat at bright absolute magnitudes but increases at faint absolute magnitudes. For the thick disc, the scaleheight is flat within the uncertainties. The local space density of the thick disc relative to the local space density for the thin disc is almost flat in the absolute magnitude intervals 5 < M(g,) , 6 and 6 < M(g,) , 7, 7.59 and 7.41 per cent respectively, whereas it decreases down to 3.31 per cent in the absolute magnitude interval 7 < M(g,) , 8. The axial ratio for the halo is ,= 0.60, 0.73 and 0.78 for the absolute magnitude intervals 4 < M(g,) , 5, 5 < M(g,) , 6 and 6 < M(g,) , 7 respectively, and its local space density relative to the local space density for the thin disc is 0.06 and 0.04 per cent for the intervals 5 < M(g,) , 6 and 6 < M(g,) , 7, respectively [the local space density relative to the thin disc could not be derived for the absolute magnitude interval 4 < M(g,) , 5 owing to a lack of the local space density for the thin disc for this interval]. The simultaneous fit of all three stellar populations agrees within uncertainties with the most recent values in the literature. Also, each parameter is close to one of the corresponding parameters estimated for different absolute magnitude intervals in this work, but with one exception: i.e. the scaleheight for the thick disc is relatively small and its error is rather large (H= 760+62,55 pc). [source] | ||||||||||