Quantitative Manner (quantitative + manner)

Distribution by Scientific Domains


Selected Abstracts


SCALES: a large-scale assessment model of soil erosion hazard in Basse-Normandie (northern-western France)

EARTH SURFACE PROCESSES AND LANDFORMS, Issue 8 2010
P. Le Gouée
Abstract The cartography of erosion risk is mainly based on the development of models, which evaluate in a qualitative and quantitative manner the physical reproduction of the erosion processes (CORINE, EHU, INRA). These models are mainly semi-quantitative but can be physically based and spatially distributed (the Pan-European Soil Erosion Risk Assessment, PESERA). They are characterized by their simplicity and their applicability potential at large temporal and spatial scales. In developing our model SCALES (Spatialisation d'éChelle fine de l'ALéa Erosion des Sols/large-scale assessment and mapping model of soil erosion hazard), we had in mind several objectives: (1) to map soil erosion at a regional scale with the guarantee of a large accuracy on the local level, (2) to envisage an applicability of the model in European oceanic areas, (3) to focus the erosion hazard estimation on the level of source areas (on-site erosion), which are the agricultural parcels, (4) to take into account the weight of the temporality of agricultural practices (land-use concept). Because of these objectives, the nature of variables, which characterize the erosion factors and because of its structure, SCALES differs from other models. Tested in Basse-Normandie (Calvados 5500,km2) SCALES reveals a strong predisposition of the study area to the soil erosion which should require to be expressed in a wet year. Apart from an internal validation, we tried an intermediate one by comparing our results with those from INRA and PESERA. It appeared that these models under estimate medium erosion levels and differ in the spatial localization of areas with the highest erosion risks. SCALES underlines here the limitations in the use of pedo-transfer functions and the interpolation of input data with a low resolution. One must not forget however that these models are mainly focused on an interregional comparative approach. Therefore the comparison of SCALES data with those of the INRA and PESERA models cannot result on a convincing validation of our model. For the moment the validation is based on the opinion of local experts, who agree with the qualitative indications delivered by our cartography. An external validation of SCALES is foreseen, which will be based on a thorough inventory of erosion signals in areas with different hazard levels. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Combined Confocal Microscopy and Stereology: a Highly Efficient and Unbiased Approach to Quantitative Structural Measurement in Tissues

EXPERIMENTAL PHYSIOLOGY, Issue 6 2002
Katherine Howell
Understanding the relationship of the structure of organs to their function is a key component of integrative physiological research. The structure of the organs of the body is not constant but changes, both during growth and development and under conditions of sustained stress (e.g. high altitude exposure and disease). Recently, powerful new techniques have become available in molecular biology, which promise to provide novel insights into the mechanisms and consequences of these altered structure-function relationships. Conventionally structure-function relationships are studied by microscopic examination of tissue sections. However, drawing conclusions about the three-dimensional structure of an organ based on this two-dimensional information frequently leads to serious errors. The techniques of stereology allow precise and accurate quantification of structural features within three-dimensional organs that relate in a meaningful way to integrated function. For example, knowledge of changes in the total surface area of the capillary endothelium in an organ can be related directly to changes in fluid filtration and permeability, or knowledge of total vessel length and mean radius allows deductions about vascular resistance. Confocal microscopy adds enormously to the power of stereological approaches. It reduces the difficulties and labour involved in obtaining suitable images. Moreover, when used in conjunction with new analytical software, it allows convenient application of stereology to small samples and those in which it is essential to maintain a specific orientation for interpretation. The information obtained will allow us to examine in a quantitative manner the altered structure-function relationships produced by manipulation of single genes and regulatory pathways in whole organisms. [source]


Calculated phase equilibria in K2O-FeO-MgO-Al2O3 -SiO2 -H2O for silica-undersaturated sapphirine-bearing mineral assemblages

JOURNAL OF METAMORPHIC GEOLOGY, Issue 4 2005
D. E. KELSEY
Abstract Silica-undersaturated, sapphirine-bearing granulites occur in a large number of localities worldwide. Such rocks have historically been under-utilized for estimating P,T evolution histories because of limited experimental work, and a consequent poor understanding of the topology and P,T location of silica-undersaturated mineral equilibria. Here, a calculated P,T projection for sapphirine-bearing, silica-undersaturated metapelitic rock compositions is constructed using THERMOCALC for the FeO-MgO-Al2O3 -SiO2 (FMAS) and KFMASH (+K2O + H2O) chemical systems, allowing quantitative analysis of silica-undersaturated mineral assemblages. This study builds on that for KFMASH sapphirine + quartz equilibria [Kelsey et al. (2004) Journal of Metamorphic Geology, vol. 22, pp. 559,578]. FMAS equilibria are significantly displaced in P,T space from silicate melt-bearing KFMASH equilibria. The large number of univariant silica-undersaturated KFMASH equilibria result in a P,T projection that is topologically more complex than could be established on the basis of experiments and/or natural assemblages. Coexisting sapphirine and silicate melt (with or without corundum) occur down to c. 900 °C in KFMASH, some 100 °C lower than in silica-saturated compositions, and from pressures of c.,1 to ,12 kbar. Mineral compositions and composition ranges for the calculated phases are consistent with natural examples. Bulk silica has a significant effect on the stability of sapphirine-bearing assemblages at a given P,T, resulting in a wide variety of possible granulite facies assemblages in silica-undersaturated metapelites. Calculated pseudosections are able to reproduce many naturally occurring silica-undersaturated assemblages, either within a single assemblage field or as the product of a P,T trajectory crossing several fields. With an understanding of the importance of bulk composition on sapphirine stability and textural development, silica-undersaturated assemblages may be utilized in a quantitative manner in the detailed metamorphic investigation of high-grade terranes. [source]


FUZZY MULTIATTRIBUTE DECISION MAKING APPROACH FOR DEVELOPMENT AND COMPARISON OF SOY FORTIFIED PANEER

JOURNAL OF SENSORY STUDIES, Issue 2 2002
SUDHIR UPRIT
ABSTRACT Soyfortified paneer (SFP) samples prepared from blends containing different proportions of buffalo milk of varying fat content and soy milk (7.5 °B) were evaluated organoleptically for assessing the quality attributes like body and texture, flavor and taste, color and appearance and the overall acceptability. Sensory data were analyzed using fuzzy logic approach, which addresses the problem of data classification in a unified qualitative and quantitative manner. Results of the study indicated that the fuzzy multiattribute decision making approach provide an adequate and reliable system for product formulation and comparison, based on sensory data. The developed fuzzy mathematical model performed remarkably well in the evaluation and ranking of various SFP samples. The SFP sample made from blend of buffalo milk (4.5% fat) and soy milk (7.5 °B) in the proportion of 90:10 was found to be the most acceptable one for different classes of consumers irrespective of their preferences for a particular sensory quality attribute. [source]


Application of a Bayesian Approach to the Tomographic Analysis of Hopper Flow

PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 4 2005
Krzysztof Grudzien
Abstract This paper presents a new approach to the analysis of data on powder flow from electrical capacitance tomography (ECT) using probability modelling and Bayesian statistics. The methodology is illustrated for powder flow in a hopper. The purpose, and special features, of this approach is that ,high-level' statistical Bayesian modelling combined with a Markov chain Monte Carlo (MCMC) sampling algorithm allows direct estimation of control parameters of industrial processes in contrast to usually applied ,low-level', pixel-based methods of data analysis. This enables reliable recognition of key process features in a quantitative manner. The main difficulty when investigating hopper flow with ECT is due to the need to measure small differences in particle packing density. The MCMC protocol enables more robust identification of the responses of such complex systems. This paper demonstrates the feasibility of the approach for a simple case of particulate material flow during discharging of a hopper. It is concluded that these approaches can offer significant advantages for the analysis and control of some industrial powder and other multi-phase flow processes. [source]


Renal and Cardiac Endothelial Heterogeneity Impact Acute Vascular Rejection in Pig-to-Baboon Xenotransplantation

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2009
C. Knosalla
Xenograft outcomes are dictated by xenoantigen expression, for example, Gal ,1, 3Gal (Gal), but might also depend on differing vascular responses. We investigated whether differential vascular gene expression in kidney and cardiac xenografts correlate with development of thrombotic microangiopathy (TM) and consumptive coagulation (CC). Immunosuppressed baboons underwent miniswine or hDAF pig kidney (n = 6) or heart (n = 7), or Gal-transferase gene-knockout (GalT-KO) (thymo)kidney transplantation (n = 14). Porcine cDNA miniarrays determined donor proinflammatory, apoptosis-related and vascular coagulant/fibrinolytic gene expression at defined time points; validated by mRNA, protein levels and immunopathology. hDAF-transgenic and GalT-KO xenografts, (particularly thymokidneys) exhibited prolonged survival. CC was seen with Gal-expressing porcine kidneys (3 of 6), only 1 of 7 baboons postcardiac xenotransplantation and was infrequent following GalT-KO grafts (1 of 14). Protective-type genes (heme oxygenase-I, superoxide dismutases and CD39) together with von Willebrand factor and P-selectin were upregulated in all renal grafts. Transcriptional responses in Gal-expressing xenografts were comparable to those seen in the infrequent GalT-KO rejection. In cardiac xenografts, fibrin deposition was associated with increased plasminogen activator inhibitor-1 expression establishing that gene expression profiles in renal and cardiac xenografts differ in a quantitative manner. These findings suggest that therapeutic targets may differ for renal and cardiac xenotransplants. [source]


Characterization of flow conditions in 2 L and 20 L wave bioreactors® using computational fluid dynamics

BIOTECHNOLOGY PROGRESS, Issue 1 2010
Alper A. Öncül
Abstract Characterization of flow conditions is of great importance to control cell growth and cell damage in animal cell culture because cell viability is influenced by the flow properties in bioreactors. Alternative reactor types like Wave Bioreactors® have been proposed in recent years, leading to markedly different results in cell growth and product formation. An advantage of Wave Bioreactors® is the disposability of the Polyethylenterephthalet-bags after one single use (fast setup of new production facilities). Another expected advantage is a lower shear stress compared to classical stirred-tank reactors, due to the gentle liquid motion in the rocking cellbag. This property would considerably reduce possible cell damage. The purpose of the present study is to investigate in a quantitative manner the key flow properties in Wave Bioreactors®, both numerically and experimentally. To describe accurately flow conditions and shear stress in Wave Bioreactors® using numerical simulations, it is necessary to compute the unsteady flow applying Computational Fluid Dynamics (CFD). Corresponding computations for two reactor scales (2 L and 20 L cellbags) are presented using the CFD code ANSYS-FLUENT®. To describe correctly the free liquid surface, the present simulations employ the Volume of Fluid (VOF) method. Additionally, experimental measurements have been carried out to determine liquid level, flow velocity and liquid shear stress, which are used as a validation of the present CFD simulations. It is shown that the obtained flows stay in the laminar regime. Furthermore, the obtained shear stress levels are well below known threshold values leading to damage of animal cells. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source]


Search for new biomarkers of gastric cancer through serial analysis of gene expression and its clinical implications

CANCER SCIENCE, Issue 5 2004
Wataru Yasui
Gastric cancer is one of the most common human cancers and is the second most frequent cause of cancer-related death in the world. Serial analysis of gene expression (SAGE) is a powerful technique to allow genome-wide analysis of gene expression in a quantitative manner without prior knowledge of the gene sequences. SAGE on 5 samples of gastric cancer with different histology and clinical stages have created large SAGE libraries of gastric cancer that enable us to identify new cancer biomarkers. Commonly up-regulated genes in gastric cancer in comparison with normal gastric epithelia included CEACAM6, APOC1 and YF13H12. By comparing gene expression profiles of gastric cancers at early and advanced stages, several genes differentially expressed by tumor stage were also identified, including FUS, CDH17, COL1A1 and COL1A2, which should be novel genetic markers for high-grade malignancy. Regenerating gene type IV (REGIV) is one of the most up-regulated genes in a SAGE library of a scirrhous-type gastric cancer. In vitro studies using RegIV-transfected cells revealed that RegIV is secreted by cancer cells and inhibits apoptosis, suggesting that RegIV may serve as a novel biomarker and therapeutic target for gastric cancer. Production of RNA aptamers could be a useful approach to establish a detection system in blood. A custom-made array, named Ex-STO-MACHIP, consisting of 395 genes, including highly differentially expressed genes identified by our SAGE and other known genes related to carcinogenesis and chemosensitivity, is useful to study the molecular pathogenesis of gastric cancer and to obtain information about biological behavior and sensitivity to therapy in the clinical setting. Combined analyses of gene expression profile, genetic polymorphism and genetic instability will aid not only cancer detection, but also characterization of individual cancers and patients, leading to personalized medicine and cancer prevention. [source]


Van der Waals and Polar Intermolecular Contact Distances: Quantifying Supramolecular Synthons

CHEMISTRY - AN ASIAN JOURNAL, Issue 5 2008
Parthasarathy Ganguly Prof.
Abstract Crystal structures are viewed as being determined by ranges and constraints on interatomic contact distances between neighboring molecules. These distances are considered to arise from environment-dependent atomic sizes, that is, larger sizes for isotropic, van der Waals type contacts and smaller sizes for more-polar, possibly ionic contacts. Although the idea of different, or anisotropic, radii for atoms is not new, we developed a method of obtaining atomic sizes that is based on a theoretical framework. Using different atomic sizes for the same atom in different environments, we were able to rationalize some structural observations and anomalies. For example, benzene with the Pbca structure may be described in terms of two types of C,,,H interactions: a longer contact largely of the van der Waals type, and a shorter, structure-determining type (C,,,,,H,+), which we term "n-polar". Our approach is illustrated with three examples: 1),the equivalence in crystal packing of fluorobenzene, benzonitrile, pyridine N -oxide, and pyridine/HF 1:1 molecular complex, all of which take the not-so-common tetragonal P41212 space group and are practically isomorphous; 2),the similarity of the Pa3 acetylene and Pbca benzene crystal structures; and 3),the equivalence between an increase in pressure and an increase in the "n-polar" contacts in Pbca benzene; in other words, the equivalence between hydrostatic pressure and chemical pressure. In the context of crystal engineering, we describe a method whereby the topological information conveyed in a supramolecular synthon is recast in a more quantitative manner. A particular synthon, and in turn the crystal structure to which it leads, is viable within small ranges of distances of its constituent atoms, and these distances are determined by chemical factors. [source]


Quantitative study on cerebral blood volume determined by a near-infrared spectroscopy during postural change in children

ACTA PAEDIATRICA, Issue 3 2009
Yasuko Taeja Kim
Abstract Aim: To investigate changes in cerebral blood volume during standing in healthy children with or without abnormal cardiovascular responses. Methods: We studied 53 children (age, 10,15 years). Cerebral oxygenated haemoglobin (oxy-Hb) and deoxygenated Hb (deoxy-Hb) were non-invasively and continuously measured using near-infrared spectroscopy (NIRS) (NIRO 300, Hamamatsu Photomedics, Shizuoka, Japan) during active standing. Beat-to-beat arterial pressure was monitored by Portapres. Results: Of 49 children with complete data acquisition, 33 had a normal cardiovascular response to the test (Group I) and 16 showed an abnormal response (Group II); nine with instantaneous orthostatic hypotension, three with postural tachycardia syndrome, three with neutrally mediated syncope and one with delayed orthostatic hypotension. At the onset of standing, Group II showed a significantly larger fall of oxy-Hb than Group I did (,2.9 ± 2.8 ,mol/L vs. ,6.4 ± 7.2 ,mol/L, respectively, p < 0.05). During min 1 to 7 of standing, with one exception, changes in oxy-Hb were normally distributed over the level of ,4 ,mol/L in Group I. Group II also showed a significantly marked decrease in oxy-Hb compared to Group I. Decreases in oxy-Hb were not correlated with blood pressure changes. Conclusion: This study shows that precise change in cerebral blood volume caused by orthostatic stress can be determined by NIRS in children in a quantitative manner of NIRS. Children with abnormal circulatory responses to standing showed a significant reduction of oxy-Hb compared with normal counterparts, suggesting impairment of cerebral autoregulation in these children. [source]