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Quantitative Way (quantitative + way)
Selected AbstractsMorphometric analysis and tectonic interpretation of digital terrain data: a case studyEARTH SURFACE PROCESSES AND LANDFORMS, Issue 8 2003Gyozo Jordan Abstract Tectonic movement along faults is often re,ected by characteristic geomorphological features such as linear valleys, ridgelines and slope-breaks, steep slopes of uniform aspect, regional anisotropy and tilt of terrain. Analysis of digital elevation models, by means of numerical geomorphology, provides a means of recognizing fractures and characterizing the tectonics of an area in a quantitative way. The objective of this study is to investigate the use of numerical geomorphometric methods for tectonic geomorphology through a case study. The methodology is based on general geomorphometry. In this study, the basic geometric attributes (elevation, slope, aspect and curvatures) are complemented with the automatic extraction of ridge and valley lines and surface speci,c points. Evans' univariate and bivariate methodology of general geomorphometry is extended with texture (spatial) analysis methods, such as trend, autocorrelation, spectral, and network analysis. Terrain modelling is implemented with the integrated use of: (1) numerical differential geometry; (2) digital drainage network analysis; (3) digital image processing; and (4) statistical and geostatistical analysis. Application of digital drainage network analysis is emphasized. A simple shear model with principal displacement zone with an NE,SW orientation can account for most of the the morphotectonic features found in the basin by geological and digital tectonic geomorphology analyses. Copyright © 2003 John Wiley & Sons, Ltd. [source] Non-random reassortment in human influenza A virusesINFLUENZA AND OTHER RESPIRATORY VIRUSES, Issue 1 2008Raul Rabadan Background, The influenza A virus has two basic modes of evolution. Because of a high error rate in the process of replication by RNA polymerase, the viral genome drifts via accumulated mutations. The second mode of evolution is termed a shift, which results from the reassortment of the eight segments of this virus. When two different influenza viruses co-infect the same host cell, new virions can be released that contain segments from both parental strains. This type of shift has been the source of at least two of the influenza pandemics in the 20th century (H2N2 in 1957 and H3N2 in 1968). Objectives, The methods to measure these genetic shifts have not yet provided a quantitative answer to questions such as: what is the rate of genetic reassortment during a local epidemic? Are all possible reassortments equally likely or are there preferred patterns? Methods, To answer these questions and provide a quantitative way to measure genetic shifts, a new method for detecting reassortments from nucleotide sequence data was created that does not rely upon phylogenetic analysis. Two different sequence databases were used: human H3N2 viruses isolated in New York State between 1995 and 2006, and human H3N2 viruses isolated in New Zealand between 2000 and 2005. Results, Using this new method, we were able to reproduce all the reassortments found in earlier works, as well as detect, with very high confidence, many reassortments that were not detected by previous authors. We obtain a lower bound on the reassortment rate of 2,3 events per year, and find a clear preference for reassortments involving only one segment, most often hemagglutinin or neuraminidase. At a lower frequency several segments appear to reassort in vivo in defined groups as has been suggested previously in vitro. Conclusions, Our results strongly suggest that the patterns of reassortment in the viral population are not random. Deciphering these patterns can be a useful tool in attempting to understand and predict possible influenza pandemics. [source] Teamworking and organizational performance: A review of survey-based researchINTERNATIONAL JOURNAL OF MANAGEMENT REVIEWS, Issue 2 2008Anne Delarue This paper presents a review of recent survey-based research looking at the contribution of teamwork to organizational performance. In particular, it focuses on empirical studies in which both teamwork and performance are directly measured in a quantitative way. The paper begins by identifying four interrelated dimensions of teamwork effectiveness: attitudinal, behavioural, operational and financial. The first two represent transmission mechanisms by which organizational performance can be improved. The latter two provide direct measures of organizational outcomes. The review shows that teamworking has a positive impact on all four dimensions of performance. It also reveals that, when teamwork is combined with structural change, performance can be further enhanced. The paper concludes by highlighting some important research gaps that future studies could address. [source] Towards a deeper understanding of test coverageJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 1 2008Teemu Kanstrén Abstract Test coverage is traditionally considered as how much of the code is covered by the test suite in whole. However, test suites typically contain different types of tests with different roles, such as unit tests, integration tests and functional tests. As traditional measures of test coverage make no distinction between the different types of tests, the overall view of test coverage is limited to what is covered by the tests in general. This paper proposes a quantitative way to measure the test coverage of the different parts of the software at different testing levels. It is also shown how this information can be used in software maintenance and development to further evolve the test suite and the system under test. The technique is applied to an open-source project to show its application in practice. Copyright © 2007 John Wiley & Sons, Ltd. [source] A friction energy approach to quantifying lubrication under fretting slidingLUBRICATION SCIENCE, Issue 2 2010T. Kolodziejczyk Abstract The problem of a proper lubrication under low-speed small oscillatory movement can be a decisive factor for the reliability of various components. There is a need to characterise the lubricious behaviour of the interface under oil-bath fretting wear conditions for ball bearing applications. Fast and reliable methods to quantify this behaviour for broad range of mechanical conditions are proposed and validated. Pure sliding reciprocation induces mixed lubrication mode. It was found that transient film profiles depend on the non-Newtonian response of the oils and the type of motion. Running-in period has a crucial importance for the tribofilm formation, and is a result of the interplay of the oil-sliding surfaces interface and is directly connected with the total energy dissipated from the contact region. The stability of structured tribofilm in steady-state period relies on the balance between the competitive processes: replenishment of the oil to the contact and ejection of the oil pending the oscillatory movement. The phenomenon of starvation was observed when the system was moved away from dynamical equilibrium and the growth of the dissipated energy was spotted. A proposed methodology provides the evaluation of the lubrication properties of the oil in a quantitative way. Copyright © 2010 John Wiley & Sons, Ltd. [source] The extent of axonal loss in the long tracts in hereditary spastic paraplegiaNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 6 2004G. C. DeLuca Hereditary spastic paraplegia (HSP) comprises a group of inherited neurodegenerative disorders with the shared characteristics of progressive weakness and spasticity predominantly affecting the lower limbs. Limited pathological accounts have described a ,dying back' axonal degeneration in this disease. However, the distribution and extent of axonal loss has not been elucidated in a quantitative way. We have studied post-mortem material from six HSP patients and 32 controls in detail. The population of axons was examined quantitatively in the corticospinal tracts from the medulla to the lumbar spinal cord and the sensory tracts from the lumbar to upper cervical spinal cord. Myelin and axon-stained sections were employed to estimate the notional area and axonal density, respectively, of both tracts. Our results indicate that in the corticospinal tracts there is a significant reduction in area and axonal density at all levels investigated in HSP compared to controls. In the corticospinal tracts, the ratio of medulla and lumbar total axonal number was significantly greater in HSP cases compared to controls suggesting more pronounced axonal loss in the distal neuraxis in HSP than in controls. The sensory tracts in HSP, in contrast, showed a significant reduction in area and axonal density only in the upper regions of the spinal cord. Similar to the corticospinal tracts, the ratio of lumbar and upper cervical cord total axonal number in the sensory tracts was increased in HSP cases compared to controls. These findings are consistent with a length-dependent ,dying back' axonopathy. Nerve fibre loss was not size-selective with both small and large diameter fibres affected. In HSP, axonal loss is widespread and symmetrical and its extent tract-specific. The characterization of the nature of axonal loss in HSP, where this is a primary phenomenon, may help the interpretation of axonal loss in conditions such as multiple sclerosis where the sequence of events is less clear. [source] Brief communication: A probabilistic approach to age estimation from infracranial sequences of maturation,AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2010Hélène Coqueugniot Abstract Infracranial sequences of maturation are commonly used to estimate the age at death of nonadult specimens found in archaeological, paleoanthropological, or forensic contexts. Typically, an age assessment is made by comparing the degree of long-bone epiphyseal fusion in the target specimen to the age ranges for different stages of fusion in a reference skeletal collection. While useful as a first approximation, this approach has a number of shortcomings, including the potential for "age mimicry," being highly dependent on the sample size of the reference sample and outliers, not using the entire fusion distribution, and lacking a straightforward quantitative way of combining age estimates from multiple sites of fusion. Here we present an alternative probabilistic approach based on data collected on 137 individuals, ranging in age from 7- to 29-years old, from a documented skeletal collection from Coimbra, Portugal. We then use cross validation to evaluate the accuracy of age estimation from epiphyseal fusion. While point estimates of age can, at least in some circumstances, be both accurate and precise based on the entire skeleton, or many sites of fusion, there will often be substantial error in these estimates when they derive from one or only a few sites. Because a probabilistic approach to age estimation from epiphyseal fusion is computationally intensive, we make available a series of spreadsheets or computer programs that implement the approach presented here. Am J Phys Anthropol 142:655,664, 2010. © 2010 Wiley-Liss, Inc. [source] Reactivity of organosilicon precursors in remote hydrogen microwave plasma chemical vapor deposition of silicon carbide and silicon carbonitride thin-film coatingsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 3 2010A. M. Wrobel Abstract A number of organosilicon precursors for silicon carbide and silicon carbonitride thin-film coatings, such as silanes, carbosilanes, aminosilanes, and disilazane, respectively, were characterized in terms of their reactivity in a remote microwave plasma chemical vapor deposition process, which was induced using hydrogen as plasma generating gas. The process displayed high selectivity with respect to the activating species and the chemical bonds in the molecular structure of the precursors. In view of very short life times of excited hydrogen plasma species the activation step takes place with an exclusive contribution of ground-state hydrogen atoms. The CH, CC, SiC, SiN, CN and NH bonds present in the molecules of the precursors are non-reactive and only the SiH or SiSi bonds play a key role in the activation step. The reactivity of the precursors was characterized in a quantitative way by the yield of the film growth parameter. The yield parameter expressing the mass of film per unit mass of the precursor fed to the reactor was calculated from the slopes of linear plots of time dependencies of film mass and precursor mass, which were determined for each investigated precursor. The reactivity of the precursors was found to be strongly dependent on the number of the SiH units present in their molecules and those containing two SiH units appeared to be most reactive. Copyright © 2009 John Wiley & Sons, Ltd. [source] Crystalline study of amorphous poly(ethylene terephthalate) sheets through annealingASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 2 2009Ruey-Shi Tsai Abstract Poly(ethylene terephthalate) (PET) sheets of different crystallinity were obtained by annealing. The annealed PET sheets were characterized by the density measurement, differential scanning calorimetry (DSC), ultraviolet (UV)-visible spectrometry, X-ray diffraction, and infrared (IR) spectrometry. The density data can be used as a basic measurement of the degree of crystallinity. The total transition heat data obtained from the first run DSC heating curves can correlate with the crystallinity, although it may underestimate the crystallinity for those samples with higher crystallinity. The visible light transmittance data can be related to the crystallinity, and are very sensitive to the change of the crystallinity for the PET sheets of low crystallinity. The X-ray diffraction data and IR transmittance data do not show strong linear relationship to the crystallinity in a quantitative way. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd. [source] 4414: Flow cytometry for the characterization of retinal neural populations and the quantification of retinal apoptosisACTA OPHTHALMOLOGICA, Issue 2010PA TSOKA Purpose The primary purpose of this study was to evaluate the potential to quantify the different retinal neuronal populations, as also the retinal detachment-induced apoptosis in Sprague,Dawley rats, in an accurate quantitative way by using flow cytometry. Methods Retinal detachment was performed on the right eye of deeply anesthetized animals. The detachment was induced by a sub-retinal injection of sodium hyaluronate. Rats were sacrifised and the eyes were enuclated to achieve retinal dissection. Tissue dissociation was accomplished with trypsin. The cells were mechanically dissociated into a single-cell suspension. At least 100.000 cells were analyzed with a FACScalibur and FlowJo software. The primary antibodies were anti-rhodopsin against rod photoreceptors, anti-PKC against rod bipolars, anti-calbindin against horizontals, anti-ChAT against cholinergic amacrine cells and anti-MAP1 against ganglion cells. Annexin-V-FITC/Propidium Iodide was used to identify apoptosis. Results Quantification of retinal neuronal cells was possible using flow cytometry. Photoreceptors had the 53.99%, the ganglion the 7%, the bipolars the 2%, the horizontal the 4% and the cholinergic amacrine cells the 1,5% in the hole mixed retinal population. Quantification of the apoptotic rate was also possible. The early apoptotic cells was 22.4% while in the control eye was 6.28% after retinal detachment. The experiments were repeated ten times and these measurements are the mean value. Conclusion Flow cytometry can be used to quantify the apoptotic neuronal cells as well as the healthy retinal neurons. It is quick and precise and it will be very useful in future in studies in neuroprotection and quantification of apoptosis during time. [source] Unifying clones with a generative programming technique: a case studyJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 4 2006Stan Jarzabek Abstract Software clones,similar program structures repeated in variant forms,increase the risk of update anomalies, blow up the program size and complexity, possibly contributing to high maintenance costs. Yet, programs are often polluted by clones. In this paper, we present a case study of cloning in the Java Buffer library, JDK 1.5. We found that at least 68% of the code in the Buffer library was contained in cloned classes or class methods. Close analysis of program situations that led to cloning revealed difficulties in eliminating clones with conventional program design techniques. As a possible solution, we applied a generative technique of XVCL (XML-based Variant Configuration Language) to represent similar classes and methods in generic, adaptable form. Concrete buffer classes could be automatically produced from the generic structures. We argue, on analytical and empirical grounds, that unifying clones reduced conceptual complexity and enhanced the changeability of the Buffer library at rates proportional to code size reduction (68%). We evaluated our solution in qualitative and quantitative ways, and conducted a controlled experiment to support this claim. The approach presented in the paper can be used to enhance genericity and changeability of any program, independently of an application domain or programming language. As the solution is not without pitfalls, we discuss trade-offs involved in its project application. Copyright © 2006 John Wiley & Sons, Ltd. [source] Critical factors in career decision making for women medical graduatesMEDICAL EDUCATION, Issue 4 2003Joanna Lawrence Background, Within the next 30 years there will be equal numbers of women and men in the medical workforce. Indications are that women are increasing their participation in specialties other than general practice, although at a slower rate than their participation in the workforce as a whole. To inform those involved in training and employment of medical women, this study investigated the influencing factors in career decision making for female medical graduates. Methods, A total of 305 women medical graduates from the University of Auckland responded to a mail survey (73% response rate) which examined influences on decision making, in both qualitative and quantitative ways, as part of a larger survey. Results, Most women were satisfied with their careers. The principal component analysis of the influencing factors identified four distinct factors important in career choice , interest, flexibility, women friendliness and job security, although the first two of these were rated more highly than the others. Conclusions, Barriers to full participation by medical women in training and employment need to be systematically examined and removed. This is not only to allow women themselves to reach their full potential, but for workforce and socio-economic reasons. Initiatives that allow and value more flexible training and work practices, particularly through the years of child raising, are necessary for women and the health care workforce at large. [source] | |||||||||||||