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Significant Parameters (significant + parameter)
Selected AbstractsCapturing human motion using body-fixed sensors: outdoor measurement and clinical applicationsCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 2 2004Kamiar Aminian Abstract Motion capture is mainly based on standard systems using optic, magnetic or sonic technologies. In this paper, the possibility to detect useful human motion based on new techniques using different types of body-fixed sensors is shown. In particular, a combination of accelerometers and angular rate sensors (gyroscopes) showed a promising design for a hybrid kinematic sensor measuring the 2D kinematics of a body segment. These sensors together with a portable datalogger, and using simple biomechanical models, allow capture of outdoor and long-term movements and overcome some limitations of the standard motion capture systems. Significant parameters of body motion, such as nature of motion (postural transitions, trunk rotation, sitting, standing, lying, walking, jumping) and its spatio-temporal features (velocity, displacement, angular rotation, cadence and duration) have been evaluated and compared to the camera-based system. Based on these parameters, the paper outlines the possibility to monitor physical activity and to perform gait analysis in the daily environment, and reviews several clinical investigations related to fall risk in the elderly, quality of life, orthopaedic outcome and sport performance. Taking advantage of all the potential of these body-fixed sensors should be promising for motion capture and particularly in environments not suitable for standard technology such as in any field activity. Copyright © 2004 John Wiley & Sons, Ltd. [source] Spatial analysis of solifluction landforms and process rates in the Abisko Mountains, northern SwedenPERMAFROST AND PERIGLACIAL PROCESSES, Issue 3 2010Hanna Ridefelt Abstract The occurrence of turf-banked solifluction landforms in the Abisko region was analysed using a grid-based approach and statistical modelling through logistic regression. Significant parameters in the model were the vegetation index NDVI, annual incoming potential radiation, wetness index, slope gradient and elevation. The model had an acceptable discrimination capacity and rather low model-fit values, but clearly showed the importance of vegetation patterns for the occurrence of solifluction at a regional scale. Solifluction movement rates measured at eight sites were combined with model parameters and the annual duration of sun hours to regionalise solifluction movement rates through an unsupervised terrain classification. For comparison, the linear relationship between the probability of solifluction occurrence and variations in movement rates was also used to regionalise movement rates. Potential geomorphic work was calculated for six different areas within the region, with the greatest being for Kärkevagge, the area with the highest precipitation. The combination of a logistic regression model of mapped landforms and field measurements of solifluction rates represents a promising methodology to assess the occurrence and activity of the process at a regional scale. Copyright © 2010 John Wiley & Sons, Ltd. [source] What is the best way to represent surface conductance for a range of vegetated sites?HYDROLOGICAL PROCESSES, Issue 9 2007Hikaru Komatsu Abstract Surface conductance Gs is a significant parameter for indicating the evaporative and photosynthetic properties of a vegetated surface. When comparing Gs values between different observation sites, some studies have used Gsmax and others have used ,smax (where Gsmax is the maximum Gs value measured during the measurement period, and ,smax is the maximum Gs value obtained with a vapour pressure deficit (VPD) of , 1·0 kPa during the measurement period). In this study, we demonstrate a clear justification for using ,smax instead of Gsmax when comparing Gs values between different sites. We examined whether both ,smax and Gsmax lead to the same conclusions in classifying vegetated sites. Komatsu (2003b) [Hydrological Processes 17: 2503,2512] reported a clear relationship between canopy height h and ,smax for coniferous forests with a projected leaf area index (LAI) of , 3·0. We examined not only the relationship between h and ,smax but also the relationship between h and Gsmax for coniferous forests with a projected LAI of , 3·0. Both ,smax and Gsmax decreased with increasing h. However, the relationship between h and Gsmax was less well defined than the relationship between h and ,smax because of biased Gsmax data. Consequently, we conclude that ,smax is a more appropriate index than Gsmax to represent Gs for sites with different vegetation. Copyright © 2007 John Wiley & Sons, Ltd. [source] Prognosis of dermal lymphatic invasion with or without clinical signs of inflammatory breast cancerINTERNATIONAL JOURNAL OF CANCER, Issue 1 2004Guenther Gruber Abstract It is still an open debate whether tumor emboli in dermal lymphatics without inflammatory signs represent a similar bad prognosis like inflammatory breast cancer. We evaluated the prognostic role of dermal lymphatic invasion (DLI) in breast cancer with (DLI + ID) or without (DLI w/o ID) inflammatory disease (ID). From August 1988 to January 2000, 42 patients with DLI were irradiated. Twenty-five were classified as pT4, 13 out of them as pT4d (inflammatory disease); the 17 remaining patients had 1 T1c, 12 T2 and 4 T3 cancers with DLI. Axillary dissection revealed node-positive disease in 39/41 patients (median, 9 positive nodes). Thirty-eight out of 42 patients received adjuvant systemic treatment(s). After a mean follow-up of 33 months, 22/42 patients (52%) are disease-free. The actuarial 3-year disease-free survival is 50% (DLI w/o ID, 61%; DLI + ID, 31%; p < 0.03); the corresponding overall survival was 69% (DLI w/o ID, 87%; DLI + ID, 37%; p = 0.005). The presence or absence of ID was the only significant parameter for all endpoints in multivariate analyses. Dissemination occurred in 19 (45%), local relapse in 7 (n = 17%) and regional failure in 4 (10%). Nine patients (21%) had contralateral breast cancer/relapse. Despite the same histopathologic presentation, DLI w/o ID offered a significantly better disease-free survival and overall survival than ID. The finding of dermal lymphatic tumor invasion predicts a high probability for node-positive disease. © 2003 Wiley-Liss, Inc. [source] Risk factors for lymph node metastasis in clinically node-negative penile cancer patientsINTERNATIONAL JOURNAL OF UROLOGY, Issue 4 2009Aravind Ramkumar Objectives: To analyze the effects of pathological T stage, grade, extent of surgery for primary tumor, and age group on the risk of developing lymph node metastasis in clinically node-negative penile cancer patients. Methods: We performed a retrospective analysis of 200 clinically node-negative penile cancer patients who were kept under surveillance, after treatment of the primary tumor in our institution. The primary outcome parameter was cytologically or histologically proven lymph node metastasis. Logistic regression analysis was used to compute odds ratios in univariate and multivariate settings. Results: Lymph node metastasis occurred in 31 patients at a median time of three months. Histological grade 3 and grade 2 tumors had a statistically significant increased odds ratio for lymph node metastasis, (7.1[P < 0.001] and 2.7 [P = 0.04], respectively), compared with grade 1 tumors. Although increasing pT stage was associated with increasing odds ratios, the differences were not statistically significant. Nor did the extent of surgery of the primary tumor or the age group significantly influence the risk of developing lymph node metastasis. Conclusions: Histological grade is the most significant parameter influencing the risk of lymph node metastasis in clinically node-negative penile cancer patients on surveillance. Patients with grade 3 and grade 2 tumors may benefit from elective inguinal lymphadenectomy. [source] Heterogeneity in chlorine susceptibility for Legionella pneumophila released from Acanthamoeba and HartmannellaJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2009C.-W. Chang Abstract Aims:, To assess chlorine susceptibility of Legionella pneumophila grown from two amoebic hosts, Acanthamoeba castellanii and Hartmannella vermiformis. Methods and Results:, After being released from amoebae, Leg. pneumophila were chlorinated at 2 and 5 mg l,1 for 5 min,24 h. Bacterial culturability and cytoplasmic membrane deterioration were quantified by culture assay on BCYE, agar and BacLight stains coupled with a fluorescent microscope, respectively. Chlorination reduced the culturability of Leg. pneumophila by 2·93,4·59 log CFU ml,1 and damaged cellular membrane by 53·8,99·2%. Moreover, cells released from H. vermiformis exhibited significantly lower degrees in culturability reduction (P = 0·0008) and membrane deterioration (P < 0·0001) when compared with those from A. castellanii. The amoebic genus is the most significant parameter affecting cytoplasmic membrane integrity of chlorinated Legionella (P < 0·0001), followed by free chlorine concentration (P = 0·042). Conclusions:,Legionella pneumophila replicated from H. vermiformis possess greater chlorine resistance than the cells from A. castellanii. Significance and Impact of the Study:, This study shows the heterogeneity of amoebae-grown Leg. pneumophila in chlorine susceptibility, which should be considered in the control of legionellae proliferation, particularly in the systems where H. vermiformis is dominant, e.g. hot water plumbing. [source] Stature Estimation from Foot Length Using Universal Regression Formula in a North Indian PopulationJOURNAL OF FORENSIC SCIENCES, Issue 1 2010D.F.M., Tanuj Kanchan M.D. Abstract:, Stature is a significant parameter in establishing identity of an unknown. Conventionally, researchers derive regression formula separately for males and females. Sex, however, may not always be determined accurately, particularly in dismembered remains and thus the need for a universal regression formula for stature estimation irrespective of sex of an individual. The study was carried out in an endogamous group of North India to compare the accuracy of sex-specific regression models for stature estimation from foot length with the models derived when the sex was presumed as unknown. The study reveals that regression equation derived for the latter can estimate stature with reasonable accuracy. Thus, stature can be estimated accurately from foot length by regression analysis even when sex remains unknown. [source] Pretransplant hepatitis C virus infection and its effect on the post-transplant course of living renal allograft recipientsJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 7 2003BEHZAD EINOLLAHI Abstract Background: Hepatitis C virus infection (HCV) is a main health problem in end-stage renal disease (ESRD) patients. The effect of pretransplant HCV infection on survival among ESRD patients who have undergone renal transplantation is controversial. We report the results of a large monocenter study that evaluated the effect of hepatitis C on the patient, and on graft survival in renal-transplanted patients who received living donated allograft. Methods: A historical cohort study, we investigated all 1006 patients who received a living kidney transplant at Baghiatollah Medical Center in Tehran, Iran, between March 1995 and October 2001 (up to 85 months follow up). Patients' sera had been routinely assayed for anti-HCV antibodies and hepatitis B surface antigen (HBsAg) at the time of transplantation. The HBsAg-positive patients were excluded from the survival analysis. Survivals were examined using Kaplan,Meier analysis and compared using the log,rank test. Multivariate analysis was performed using Cox's model. Results: Forty-five patients (4.5%) were anti-HCV-antibody positive. Anti-HCV-antibody-positive patients spent a longer time on dialysis and had a higher rate of retransplantation. There were no differences in recipients' sex and age and donors' age between the two groups. The 7-year patient survival rate was 89.9% in the anti-HCV-antibody-positive group and 95.5% in the HCV-negative group (P = 0.74). Seven-year graft survival was 82.0% and 75.0% in the anti-HCV-antibody-positive and HCV-negative groups, respectively (P = 0.39). In the multivariate analysis, age was the only significant parameter correlated with patient survival (P = 0.02). Conclusions: HCV infection does not seem to influence patient and graft survival within a medium-time follow up in living allograft recipients, and anti-HCV-antibody positive status (alone) is not a contraindication for renal transplantation. However, further studies are needed to better define the role of HCV infection in long-term prognosis. © 2003 Blackwell Publishing Asia Pty Ltd [source] Morphological and morphometric attributes of epididymal and testicular spermatozoa following surgical sperm retrieval for obstructive and nonobstructive azoospermiaANDROLOGIA, Issue 6 2003Dr. S. Wood Summary. Whilst the morphological (shape) and morphometric (sperm head size) attributes of ejaculated spermatozoa have been well studied, the morphological and morphometric qualities of testicular and epididymal spermatozoa retrieved from males with obstructive and nonobstructive azoospermia is much less documented. We wished to examine the effect of aetiology of azoospermia and site of retrieval on the attributes of retrieved spermatozoa. This was a prospective observational study of 30 consecutive successful sperm retrievals, six for nonobstructive azoospermia and 24 for obstructive, of which five were retrieved from the epididymis and the remainder from the testis. The proportion of morphologically normal testicular spermatozoa in patients with obstructive and nonobstructive azoospermia was not significantly different (7% versus 7.6%, P = 0.97). Testicular spermatozoa from males with obstructive azoospermia showed an increase in frequency of sperm with small heads [47/180 (26%) versus 97/909 (11%), P = 0.036] as well as small acrosome and increasing vacuole formation over nonobstructive spermatozoa. Similarly, there was a significant increase in tail deformities and decreases in tail lengths in sperm from males with nonobstructive azoospermia. Epididymal spermatozoa showed significantly greater proportion of morphologically normal spermatozoa than testicular (20% versus 13%, P = 0.001) as well as a significant increase in acrosome vacuoles. Furthermore, morphometrically epididymal spermatozoa displayed with smaller head length, width and area than testicular spermatozoa. Testicular spermatozoa from obstructive azoospermia displayed significantly less tail defects (35% versus 57%, P = 0.003) as well as significantly longer tail lengths (30.6 ,m versus 10.7 ,m). These morphological and morphometric differences between epididymal and testicular and obstructive and nonobstructive spermatozoa may represent part of the natural maturation process. There were no associations between any morphological or morphometric abnormality with any significant parameter in subsequent use in ICSI. [source] Time-dependent Variations in Ischemia-modified Albumin Levels in Mesenteric IschemiaACADEMIC EMERGENCY MEDICINE, Issue 6 2009Abdulkadir Gunduz MD Abstract Objectives:, The objective was to determine the value of ischemia-modified albumin (IMA) in the diagnosis of mesenteric embolism. The authors investigated whether or not plasma IMA levels rose in the acute period in a rat model of mesenteric ischemia and the related time-dependent changes. Methods:, In this randomized, controlled, nonblinded trial, 36 mature female Wistar rats were divided into six groups: three control (Groups I, III, and V) and three ischemia (Groups II, IV, and VI). In the control groups, blood was sampled at 30 minutes (Group I), 2 hours (Group III), and 6 hours (Group V) following a simple laparotomy. In the ischemia groups, following laparotomy, the superior mesenteric artery (SMA) was clamped using a bulldog clamp, and blood samples were taken at 30 minutes (Group II), 2 hours (Group IV), and 6 hours (Group VI). Results:, Plasma IMA levels in the ischemia groups were significantly higher compared to those of the control groups (p < 0.004). In addition, levels were higher in the 6-hour blood samples of the ischemia group than in the 2-hour and 30-minute samples (p < 0.001). Serum IMA was also higher in the 2-hour blood samples of the ischemia group than in the 30-minute samples (p < 0.001). Conclusions:, These preliminary findings suggest that serum IMA levels may represent a significant parameter in the early diagnosis of acute mesenteric ischemia and that further studies are necessary. [source] NOx emissions of an opposed wall-fired pulverized coal utility boilerASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2010Xiaotao Gao Abstract The present paper was addressed to the effects of operational variables and coal properties on NOx emission level of a 600-MW opposed wall-fired pulverized coal utility boiler. The in situ experiments were performed to study the effects of operational variables on boiler performance by changing individual variables while the other variables were held nearly constant on the basis of the nominal load operation. It was found that the oxygen level was a significant parameter to affect the NOx emission. The impacts of coal properties on NOx emission indicated that NOx emission level decreased with the increase of the ratio of the nitrogen content to low heating value because the volatile matter content in coal significantly influenced the in-flame NOx formation. Coal volatile content was the dominant parameter to affect fuel NOx formation through affecting the reducing condition in the inner near-burner zone when the low NOx burners were applied in the boiler. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Comparing performances of logistic regression and neural networks for predicting melatonin excretion patterns in the rat exposed to ELF magnetic fieldsBIOELECTROMAGNETICS, Issue 2 2010Samad Jahandideh Abstract Various studies have been reported on the bioeffects of magnetic field exposure; however, no consensus or guideline is available for experimental designs relating to exposure conditions as yet. In this study, logistic regression (LR) and artificial neural networks (ANNs) were used in order to analyze and predict the melatonin excretion patterns in the rat exposed to extremely low frequency magnetic fields (ELF-MF). Subsequently, on a database containing 33 experiments, performances of LR and ANNs were compared through resubstitution and jackknife tests. Predictor variables were more effective parameters and included frequency, polarization, exposure duration, and strength of magnetic fields. Also, five performance measures including accuracy, sensitivity, specificity, Matthew's Correlation Coefficient (MCC) and normalized percentage, better than random (S) were used to evaluate the performance of models. The LR as a conventional model obtained poor prediction performance. Nonetheless, LR distinguished the duration of magnetic fields as a statistically significant parameter. Also, horizontal polarization of magnetic fields with the highest logit coefficient (or parameter estimate) with negative sign was found to be the strongest indicator for experimental designs relating to exposure conditions. This means that each experiment with horizontal polarization of magnetic fields has a higher probability to result in "not changed melatonin level" pattern. On the other hand, ANNs, a more powerful model which has not been introduced in predicting melatonin excretion patterns in the rat exposed to ELF-MF, showed high performance measure values and higher reliability, especially obtaining 0.55 value of MCC through jackknife tests. Obtained results showed that such predictor models are promising and may play a useful role in defining guidelines for experimental designs relating to exposure conditions. In conclusion, analysis of the bioelectromagnetic data could result in finding a relationship between electromagnetic fields and different biological processes. Bioelectromagnetics 31:164,171, 2010. © 2009 Wiley-Liss, Inc. [source] HLA-DR expression on lymphocyte subsets as a marker of disease activity in patients with systemic lupus erythematosusCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2001J. F. Viallard A major problem in the management of SLE patients is to predict a flare or to distinguish between active and quiescent disease. Serological markers are widely used to assess disease activity, but many patients have close to or normal values for these parameters while exhibiting obvious disease-related signs and symptoms. This study aimed to determine which serological parameters, among ESR, ANA and anti-dsDNA antibody titres, CH50 and the HLA-DR expression on circulating T-lymphocyte subsets, best reflected the development of SLE flares. Sixty SLE patients were included, 34 with quiescent disease throughout the entire follow-up period and 26 who experienced an SLE flare defined as having active disease. According to univariate analysis, all parameters were significantly higher for patients with active disease, with the percentage of CD8+DR+ cells being the most significant parameter (P = 10,7). Multivariate logistic regression analysis identified three independent variables enabling the identification of a lupus flare: CH50, the CD8+DR+ and CD4+DR+ cell percentages among total lymphocytes. The CD8+DR+ cell percentage is the biological parameter most significantly associated with a flare (P < 0·001), even more powerful than CH50 (P < 0·01). HLA-DR expression on CD8+ lymphocytes clearly coincided with disease evolution in seven patients enrolled as having quiescent disease, but who experienced one flare during follow-up that subsequently resolved. The percentage of circulating CD8+DR+ lymphocytes appears to be a biological marker which accurately reflects disease activity. A larger prospective study is needed to demonstrate the real efficacy of this marker in predicting an exacerbation in SLE patients. [source] Two yr mycophenolate mofetil plus low-dose calcineurin inhibitor for renal dysfunction after liver transplantCLINICAL TRANSPLANTATION, Issue 2 2009Maurizio Biselli Abstract:, We assessed the efficacy and outcome of low through level of calcineurin inhibitors (CNI) and introducing mycophenolate mofetil (MMF) in liver transplant (LT) patients with CNI-related renal dysfunction. Thirty LT patients were converted to combined therapy and compared with 30 patients used as a contemporary control group receiving CNI only. The two groups were matched for sex, age, months after LT, immunosuppressive treatment, creatinine level, presence of diabetes and calculated glomerular filtration rate (GFR) via Cockroft-Gault method. After two years, in the MMF serum creatinine decreased from 1.65 mg/dL (range 1.33,3.5) to 1.4 mg/dL (range 0.9,4.7) (p = 0.002) and GFR increased from 51 mL/min (range 18.9,72.2) to 57.6 mL/min (range 16,92.2) (p < 0.001), whereas the controls not showed any improvement. The logistic regression models employing improvement of creatinine and GFR of at least 10% with respect to baseline as dependent variables showed the use of MMF (p = 0.004 and p = 0.019, respectively) as the only statistically significant parameter. Multiple linear regression analysis identified only MMF as independent predictor of ,creatinine and ,GFR (p = 0.002 and p < 0.001, respectively). No rejection episode was observed (three in controls). This study demonstrates the medium-term efficacy and safety of MMF plus low dose CNI in reducing nephrotoxicity in LT recipients. [source] Role of computerized morphometric analysis in diagnosis of effusion specimensDIAGNOSTIC CYTOPATHOLOGY, Issue 10 2006B. Arora M.D. Abstract The present study was undertaken to compare morphometric analysis of cells in 100 effusion samples, with unaided cytological diagnosis. All the cases in the form of Leishman's stained smears were subjected to computerized-interactive morphometry (CIM) by usage of Image analysis software. On routine cytological examination, 44 cases were benign, 26 were malignant, and 30 cases were placed in "atypical" category. On morphometry, values for mean nuclear area (MNA) and mean cytoplasmic area (MCA) in benign cases were found to be 58.39 ± 12.22 ,m2 and 185.70 ± 43.69 ,m2, while for malignant cases were 120.12 ± 16.28 ,m2 and 274.65 ± 61.01 ,m2, respectively (P < 0.001, P < 0.001, highly significant). Significant differences were also noted among benign, atypical, and malignant cases for MNA (P < 0.001). The differences between atypical and malignant cases for N/C (nuclear/cytoplasmic) ratio were also found to be statistically significant (P < 0.001). Finally, 46 cases were found to be benign, 39 malignant, and 15 in the category of atypical cases. CIM helps in better and quicker sorting for malignant cells. MNA and N/C ratio are the most significant parameters in differentiating various cells in effusions. MCA constitutes as another useful parameter. Salient features of CIM, including their applications in the light of current study, are discussed. Diagn. Cytopathol. 2006;34:670,675. © 2006 Wiley-Liss, Inc. [source] Short-term electric power load forecasting using feedforward neural networksEXPERT SYSTEMS, Issue 3 2004Heidar A. Malki Abstract: This paper presents the results of a study on short-term electric power load forecasting based on feedforward neural networks. The study investigates the design components that are critical in power load forecasting, which include the selection of the inputs and outputs from the data, the formation of the training and the testing sets, and the performance of the neural network models trained to forecast power load for the next hour and the next day. The experiments are used to identify the combination of the most significant parameters that can be used to form the inputs of the neural networks in order to reduce the prediction error. The prediction error is also reduced by predicting the difference between the power load of the next hour (day) and that of the present hour (day). This is a promising alternative to the commonly used approach of predicting the actual power load. The potential of the proposed method is revealed by its comparison with two existing approaches that utilize neural networks for electric power load forecasting. [source] Transmission on indoor power lines: from a stochastic channel model to the optimization and performance evaluation of multicarrier systemsINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 5 2003Virginie Degardin Abstract This paper deals with optimization and performance evaluation of multicarrier transmissions on indoor power lines, taking the actual channel characteristics into account. From intensive measurements of noise on lines, the most significant parameters of impulsive noise were defined and classified, and then a statistical study was carried out. The other types of noise, i.e. narrow band and coloured noise have also been characterized. In like manner, the transfer functions between two points of a power line network have been measured. From all these data, a stochastic channel model representative of the environment is built and implemented in a software tool simulating the link. Various transmission schemes have been considered to mitigate the effects on one hand of the stationary noise, the channel frequency selectivity and of the change of its state, and on the other, on the impulsive noise. These techniques are optimized for the indoor power line environment and their performances, expressed in terms of bit error rate, are compared. Copyright © 2003 John Wiley & Sons, Ltd. [source] Diagnostic clues to megaloblastic anaemia without macrocytosisINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 3 2007C. W. J. CHAN Summary Masking of the macrocytic expression of megaloblastic anaemia (MA) by coexisting thalassaemia, iron deficiency and chronic illness has been widely reported. We described the haematological and clinical features of 20 Chinese patients with MA presenting with mean corpuscular volume (MCV) ,99 fl, and analysed the steps leading to the final diagnosis of MA with concomitant thalassaemia trait (n = 11), thalassaemia trait and iron deficiency (n = 3), iron deficiency (n = 4) and chronic illness (n = 2). We also compared the haematological characteristics of this group of patients with a group of normocytic anaemic patients without vitamin B12/folate deficiency, and identified certain laboratory information useful for differentiating the two groups. Statistically significant parameters included the mean values of haemoglobin, MCV, red cell distribution width (RDW), reticulocyte index, platelet count and serum bilirubin. All provided clues to maturation disorders within the marrow. A decision flowchart for the diagnosis of MA without macrocytosis was proposed. In the studied population, by using the parameters of haemoglobin <10 g/dl, MCV 80,99 fl, RDW , 16% and reticulocyte index , 2% as indicators, there was a 58% chance that a patient had MA without macrocytosis if he/she had all the four indicators, and a 2.2% chance of having it if he/she did not have these indicators. We emphasized the importance of including peripheral blood smear examination in the diagnostic procedures for such patients, as well as the importance of paying attention to patients' medical history, racial background and previous MCV value. [source] Inferential non-centred principal curve analysis of time-intensity curves in sensory analysis: the methodology and its application to beer astringency evaluationJOURNAL OF CHEMOMETRICS, Issue 5-6 2007Nancy François Abstract Improving technologies and better understanding of sensory phenomena have lead sensory analysts to develop statistical methods to assess sensations that endure over time (e.g. the bitterness or astringency of a beer) dynamically. The data produced by this type of experiment is classically a time-intensity (TI) curve, and their analysis remains an active research topic. The classical approach, widely used in this context, starts by extracting some significant parameters from the initial curves (maximum intensity, area under the curve (AUC), etc.). Descriptive data analysis or statistical modelling is then applied to get information from these summary parameters. This paper presents a different method, called inferential non-centred principal curve analysis (INCPCA), for the analysis of TI curves. It combines multivariate analysis (to visualise the curves in a space of smaller dimensions) with statistical modelling (aimed at enhancing the significance of factor effects). Non-centred principal curves (NCPCs) are first extracted from the curves matrix. They decompose the TI curves into different interpretable components. Score plots are used to represent the projection of the initial curves in the space of the first principal curves and allow factors and judge effects to be visualised. Mixed modelling is then applied to test the significance of these effects using PCA scores as model responses. The classical and INCPCA methods are illustrated on a TI experiment exploring the relation between beer astringency and three factors of interest: pH, O2 content and aging. Eight beers arranged in a 23 factorial design were tested in triplicate by eight trained judges. Copyright © 2007 John Wiley & Sons, Ltd. [source] A NUMERICAL APPROACH WITH VARIABLE TEMPERATURE BOUNDARY CONDITIONS TO DETERMINE THE EFFECTIVE HEAT TRANSFER COEFFICIENT VALUES DURING BAKING OF COOKIESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2006EREN DEMIRKOL ABSTRACT The increasing trade of ready-to-eat foods such as cookies highlights an interest in quality defects during baking. Heat (h and thermal diffusivity) and mass (mass transfer and diffusion coefficients) transfer parameters are significant parameters affecting the quality changes. Therefore, it is important to determine these parameters for modeling and process optimization studies. Among these, the h is important, revealing the relationship between the heating medium and product surface. As baking involves a simultaneous heat and mass transfer involving moisture diffusion and heat conduction inside and convective heat and mass transfer outside, a lumped system method may not be an accurate choice to determine the h value. Changes in the product volume and contact heating from bottom of the product also bring extra challenges to the determination of h. Therefore, the objective of this study was to use realistic approaches including simultaneous heat and mass transfer to determine the changes in h. The heffvalues for the bottom and top surface of the cookies were then determined, applying a numerical procedure where the surface temperature changes were the boundary conditions with evaporation on the surface. The hband ht values increased with baking temperature and varied with baking time. The results of this study showed that evaporative mass flux for the top surface, heat flux for the bottom surface and the product's volume changes were significant in the variation of h values. [source] New Keynesian Macroeconomics and the Term StructureJOURNAL OF MONEY, CREDIT AND BANKING, Issue 1 2010GEERT BEKAERT monetary policy; inflation target; term structure of interest rates; Phillips curve This article complements the structural New Keynesian macro framework with a no-arbitrage affine term structure model. Whereas our methodology is general, we focus on an extended macro model with unobservable processes for the inflation target and the natural rate of output that are filtered from macro and term structure data. We find that term structure information helps generate large and significant parameters governing the monetary policy transmission mechanism. Our model also delivers strong contemporaneous responses of the entire term structure to various macroeconomic shocks. The inflation target shock dominates the variation in the "level factor" whereas monetary policy shocks dominate the variation in the "slope and curvature factors." [source] E-cadherin expression in early gastric carcinoma and correlation with lymph node metastasisJOURNAL OF SURGICAL ONCOLOGY, Issue 5 2007Dong Yi Kim MD Abstract Objective Abnormal expression of E-cadherin plays an important role in the differentiation and progression of gastric carcinoma. However, the relationship between molecular changes in E-cadherin and metastasis in early gastric carcinoma (EGC) is poorly understood. Materials and Methods Sixty cases of EGC with or without lymph node metastasis (30 node-positive cases and 30 node-negative cases) were investigated to evaluate hypermethylation status using bisulfate-MSP and immunohistochemistry using antibody against E-cadherin. Results Twenty-seven (45.0%) of 60 primary EGCs exhibited methylation in the CpG island of E-cadherin. Abnormal expression of E-cadherin was significantly correlated with patient age, tumor size, Lauren classification, differentiation, and lymph node metastasis. Using multiple logistic regression analysis, two factors were independent, statistically significant parameters associated with lymph node metastasis: abnormal expression of E-cadherin (risk ratio, 2.62; 95% confidence interval, 0.917,7.457; P,<,0.05) and lymphatic invasion (risk ratio, 8.11; 95% confidence interval, 1.612,40.766; P,<,0.05). Conclusion Our results suggest that methylation of E-cadherin is a frequent, early event in gastric carcinoma progression, and is correlated significantly with downregulated E-cadherin expression. Inactivation of E-cadherin might be involved in metastasis in EGC and play an important role in microscopic differentiation. J. Surg. Oncol. 2007;96:429,435. © 2007 Wiley-Liss, Inc. [source] Characterization of Electrical Properties of Li(FexAl1,x)5O8 Solid Solutions by Impedance SpectroscopyJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2000Shuichi Arakawa To examine polaronic transport properties in Li(FexAl1,x)5O8 spinel solid solutions, a scaling analysis for their conductivity spectra and modulus spectra was performed. As in the case of ionic conductors, two significant parameters of a crossover frequency and a power-law exponent were extracted from the conductivity spectra which displayed the universal dynamic response behavior. Both the mobility and the concentration of carriers were successfully determined from the crossover frequency. The power-law exponent and the stretching parameter obtained from the modulus spectra varied with composition, implying that the increase in Fe concentration would enhance the Coulomb interactions between small polarons. [source] Laser even harmonics generation by a plasma embedded in a static electric fieldLASER PHYSICS LETTERS, Issue 4 2004G. Ferrante Abstract Even order harmonics generation of the laser radiation due to electron-ion collisions in a plasma embedded in a constant electric field is investigated theoretically. Even harmonics are generated because the presence of a static electric field removes the invariance of the electron distribution function under the symmetry operation of velocity direction inversion. Efficiency generation dependencies are investigated vs different significant parameters as: harmonics number; the ratio of the electron quiver velocity to the thermal velocity; the orientation of the constant electric field with respect to the laser radiation electric field and its wavevector. It is shown that in the general case the polarization planes of different even harmonics are different and do not coincide with that of the generating laser radiation. (© 2004 by ASTRO, Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source] Score system for elective tracheotomy in major head and neck tumour surgeryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2005B. Kruse-Lösler Background:, This study was designed to evaluate prognostic parameters for respiratory failure after major oropharyngeal resections in head and neck cancer surgery, focusing on a score system to identify patients requiring an elective tracheotomy and to avoid tracheotomy under emergency conditions. Methods:, One hundred and fifty-two out of 928 patients with oropharyngeal cancers, treated between January 1993 and June 2000 at our hospital, fulfilled the inclusion criteria for a retrospective analysis. This collective underwent tumour resection in different regions of the oropharynx combined with bony resection of the mandible and neck dissection without primary tracheotomy. The reconstruction was accomplished using radial forearm flaps (n1 = 59) or local flaps (n2 = 93). These two groups were subdivided into patients treated post-operatively by tracheotomy due to respiratory failure (n1 = 26; n2 = 12) and those without such treatment (n1 = 33; n2 = 81). The database comprising tumour localization and size, staging, general medical condition, smoking and alcohol consumption was evaluated by logistic regression. Results:, We developed a score system which predicts the likelihood of post-operative respiratory failure. For indication of tracheotomy, tumour size and localization, multimorbidity, alcohol consumption and pathologic chest X-ray findings were identified as significant parameters with different weightings. The predictive value for tracheotomy (yes/no) using the score system was 96.7% for the total collective. Conclusion:, The decision on whether or not an elective tracheotomy in major head and neck tumour surgery is necessary can be facilitated using this score system which is based on objective facts. It may reduce post-operative complications and contribute to safer treatment. [source] Air Current Segregation of Alumina PowderPARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 2 2007Stefan Zigan Abstract This paper outlines the industrial problem of air current segregation in alumina storage silos which occurs with the handling of the feedstock alumina in aluminium plants and investigates the parameters that affect the severity of the segregation. Bates [1] stated that the feeding rate influences segregation which we can confirm with own experimental findings. Higher powder flow rates tend to reduce air current segregation. Cooper et al. [2] pointed out that the air extraction rate affects the content of fine particles (dust) in the circulating air currents and we confirm his finding. The importance of the effect of different feeding rates on air current segregation was discovered in a two dimensional apparatus. The investigation of the influence of air extraction rate was realised in a cylindrical silo. Both experiments show a strong relationship between the strength of the particle-air flow in the silo and air current segregation. It is found that an increase of the powder feeding rate or the air extraction rate reduces air current segregation in the experimental equipment. The aim of our experiments was to find all significant parameters and to apply dimensional analysis to develop a method which scales the findings from small scale experiments to large industrial alumina silos. Five dimensionless groups were obtained, which is unwieldy. To reduce the number of dimensionless groups, physical properties were lumped into the terminal velocity. This simplified approach gives three dimensionless groups. Experiments in a water model and an air model justify more research using this simplified scaling method. [source] Estimation of the number of working hours critical for the development of mental and physical fatigue symptoms in Japanese male workers,application of benchmark dose methodAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 3 2007Yasushi Suwazono PhD Abstract Background To clarify the influence of working hours on subjective fatigue symptoms and obtain the critical dose (number of hours) to determine the number of permissible working hours, we calculated the benchmark dose (BMD) and the 95% lower confidence limit on BMD (BMDL) of working hours for subjective mental and fatigue symptoms using multivariate logistic regression. Methods Self-administered questionnaires were distributed to all 843 male daytime workers aged ,60 years in a single chemical factory, and 715 provided complete replies. The odds ratios of daily working hours were determined using positive findings of the Self-rating Depression Scale and 8 subscales of the Cumulative Fatigue Symptom Index as dependent variables, and other potential covariates as independent variables. Using significant parameters for the working hours and those for other covariates, the BMD and BMDL (BMD/BMDL) values were calculated for corresponding dependent variables. The benchmark response (BMR) was set at 5% or 10%. Results The BMDL with a BMR of 5% was shown to be 9.6,11.6 hr per day, which corresponds to 48,58 working hours per week and 36,78 overtime hours per month. Conclusions These results suggest that special attention should be paid to the workers whose working hours exceed these BMD/BMDL values. Am. J. Ind. Med. 50: 173,182, 2007. © 2007 Wiley-Liss, Inc. [source] Trabecular bone structure in the mandibular condyles of gouging and nongouging platyrrhine primatesAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2010Timothy M. Ryan Abstract The relationship between mandibular form and biomechanical function is a topic of significant interest to morphologists and paleontologists alike. Several previous studies have examined the morphology of the mandible in gouging and nongouging primates as a means of understanding the anatomical correlates of this feeding behavior. The goal of the current study was to quantify the trabecular bone structure of the mandibular condyle of gouging and nongouging primates to assess the functional morphology of the jaw in these animals. High-resolution computed tomography scan data were collected from the mandibles of five adult common marmosets (Callithrix jacchus), saddle-back tamarins (Saguinus fuscicollis), and squirrel monkeys (Saimiri sciureus), respectively, and various three-dimensional morphometric parameters were measured from the condylar trabecular bone. No significant differences were found among the taxa for most trabecular bone structural features. Importantly, no mechanically significant parameters, such as bone volume fraction and degree of anisotropy, were found to vary significantly between gouging and nongouging primates. The lack of significant differences in mechanically relevant structural parameters among these three platyrrhine taxa may suggest that gouging as a habitual dietary behavior does not involve significantly higher loads on the mandibular condyle than other masticatory behaviors. Alternatively, the similarities in trabecular architecture across these three taxa may indicate that trabecular bone is relatively unimportant mechanically in the condyle of these primates and therefore is functionally uninformative. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] A Framework for Unifying Formal and Empirical AnalysisAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 3 2010Jim Granato An important disconnect exists between the current use of formal modeling and applied statistical analysis. In general, a lack of linkage between the two can produce statistically significant parameters of ambiguous origin that, in turn, fail to assist in falsifying theories and hypotheses. To address this scientific challenge, a framework for unification is proposed. Methodological unification leverages the mutually reinforcing properties of formal and applied statistical analysis to produce greater transparency in relating theory to test. This framework for methodological unification, or what has been referred to as the empirical implications of theoretical models (EITM), includes (1) connecting behavioral (formal) and applied statistical concepts, (2) developing behavioral (formal) and applied statistical analogues of these concepts, and (3) linking and evaluating the behavioral (formal) and applied statistical analogues. The elements of this EITM framework are illustrated with examples from voting behavior, macroeconomic policy and outcomes, and political turnout. [source] Good modeling practice for PAT applications: Propagation of input uncertainty and sensitivity analysisBIOTECHNOLOGY PROGRESS, Issue 4 2009Gürkan Sin Abstract The uncertainty and sensitivity analysis are evaluated for their usefulness as part of the model-building within Process Analytical Technology applications. A mechanistic model describing a batch cultivation of Streptomyces coelicolor for antibiotic production was used as case study. The input uncertainty resulting from assumptions of the model was propagated using the Monte Carlo procedure to estimate the output uncertainty. The results showed that significant uncertainty exists in the model outputs. Moreover the uncertainty in the biomass, glucose, ammonium and base-consumption were found low compared to the large uncertainty observed in the antibiotic and off-gas CO2 predictions. The output uncertainty was observed to be lower during the exponential growth phase, while higher in the stationary and death phases - meaning the model describes some periods better than others. To understand which input parameters are responsible for the output uncertainty, three sensitivity methods (Standardized Regression Coefficients, Morris and differential analysis) were evaluated and compared. The results from these methods were mostly in agreement with each other and revealed that only few parameters (about 10) out of a total 56 were mainly responsible for the output uncertainty. Among these significant parameters, one finds parameters related to fermentation characteristics such as biomass metabolism, chemical equilibria and mass-transfer. Overall the uncertainty and sensitivity analysis are found promising for helping to build reliable mechanistic models and to interpret the model outputs properly. These tools make part of good modeling practice, which can contribute to successful PAT applications for increased process understanding, operation and control purposes. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] | ||||||||||||||||||||||||||||