Distribution Of Characteristic Research Articles

Multiple HPV subtypes infection in Japanese oral squamous cell carcinoma

Human papillomavirus (HPV) infection may be independent risk factor for oral squamous cell carcinoma (OSCC). Many previous studies have also demonstrated the prevalence of HPVs in oral epithelial tissue. However, the relationship of HPV to OSCC is still controversy. The aim of this study was to determine the prevalence of HPV and subtypes in OSCC patients.DNA samples were collected from 93 OSCC tissues. We assessed prevalence of HPV and subtypes involvement in OSCC patients using the Roche Linear Array HPV Genotyping Test. Distribution of each clinical characteristic was compared with HPV status.HPV infection was found in 10 OSCC patients (10.7%). We detected multiple subtypes including high and low risk type in all HPV positive OSCC tissue samples. However, there was no significant correlation between HPV infection and all clinical characteristics.In this study, all HPV positive OSCC samples have more than 2 HPV subtypes. Although it was not reported that infection of multiple subtypes was a risk factor in OSCC, our results suggested that multiple subtypes infection of HPV might be participating in OSCC.

Nonparametric Progressive Mean Control Chart for Monitoring Process Target

Nonparametric control charts are widely used when the parametric distribution of the quality characteristic of interest is questionable. In this study, we proposed a nonparametric progressive mean control chart, namely the nonparametric progressive mean chart, for efficient detection of disturbances in process location or target. The proposed chart is compared with the recently proposed nonparametric exponentially weighted moving average and nonparametric cumulative sum charts using different run length characteristics such as the average run length, standard deviation of the run length, and the percentile points of the run length distribution. The comparisons revealed that the proposed chart outperformed recent nonparametric exponentially weighted moving average and nonparametric cumulative sum charts, in terms of detecting the shifts in process target. A real life example concerning the fill heights of soft drink beverage bottles is also provided to illustrate the application of the proposed nonparametric control chart. Copyright © 2012 John Wiley & Sons, Ltd.

A Study on the Effects of Non-Normality on the Performances of Max-DEWMA Versus SS-DEWMA Charts

Problem statement: The called the Sum of Squares Double Exponentially Weighted Moving Average (SS-DEWMA) chart which is effective in detecting shifts in the mean and/or variance is compared with the Max-DEWMA (called the maximum double exponentially weighted moving average) chart. The comparison is based on the assumption that the distribution of the quality characteristic of the process is normal or approximately normally distributed. In many real world situations, this assumption may be violated. This study compares the effects of various forms of non-normality on the Max-DEWMA and SS-DEWMA control charts. Approach: A Monte Carlo simulation using the Statistical Analysis Software (SAS) is conducted to compare the performances of the two charts for the case of skewed distributions, such as the Weibull, lognormal and gamma distributions. Results: The overall results show that the Max-DEWMA chart has in-control Average Run Lengths (ARLs) closer to the specified value, as compared to that of the SS-DEWMA chart, for all levels of skewnesses considered. Conclusion/Recommendation: Practitioners are advised to use the Max-DEWMA chart for a joint monitoring of the process mean and/or variance, when the underlying distribution is non-normal.

The Economic Performance of a CUSUM t Control Chart for Monitoring Short Production Runs

At the start of a production run, the parameters of the distribution of a quality characteristic are frequently unknown. If the quality characteristic should by monitored on-line by means of a control chart and the production run length is too short, then it is impossible to get a sufficient Phase I number of samples allowing for the correct estimation of parameters and the evaluation of the chart’s tentative limits. To overcome this problem, in this paper the economic design of a CUSUM t control chart that is able to monitor short production runs without the need of Phase I samples is proposed. A numerical analysis aimed at comparing the economic performance of the CUSUM t chart vs. the CUSUM X̄ chart with known parameters has been performed on a benchmark of scenarios available from literature. The obtained results show that the expected economic loss associated to the implementation of the CUSUM t chart is quite negligible with respect to the control chart with known parameters. An illustrative example is provided to show the CUSUM t chart’s implementation.

Reversed polarity of bipolar electrograms for predicting a successful ablation site in focal idiopathic right ventricular outflow tract arrhythmias

Radiofrequency catheter ablation (RFCA) for idiopathic right ventricular outflow tract (RVOT) arrhythmias is typically guided by local activation time (LAT) mapping and unipolar electrogram morphology (QS configuration). However, LAT mapping is limited by the large variation among patients, and the area demonstrating a QS configuration of the unipolar electrogram may be larger than the focal source. Reversed polarity has been proposed as a criterion for guiding RFCA. The purpose of this study was to investigate the value of reversed polarity of adjacent bipolar electrograms for predicting a successful ablation site in idiopathic RVOT arrhythmias. Twenty-five consecutive patients (12 men [48%], age 43 ± 15 years) undergoing RFCA for RVOT arrhythmia were studied. Electrograms of ablation sites and of points within a 15-mm radius to the successful site were evaluated for LAT, unipolar electrogram morphology, and the presence of reversed polarity of adjacent bipolar electrograms. Electrogram characteristics of successful ablation sites were compared to those of nonsuccessful ablation sites. The spatial distribution of each electrogram characteristic was studied. Successful ablation sites more often demonstrated reversed polarity and had an earlier LAT than nonsuccessful sites. A wide spatial distribution was observed for unipolar electrograms with a QS configuration around the successful ablation site. Mapping based on LAT and reversed polarity had a higher predictive value for a successful ablation site than mapping based on LAT and QS configuration. The presence of reversed polarity has a high predictive value for successful ablation sites in focal idiopathic RVOT arrhythmias and is likely to reduce the number of RFCA applications.

A quantile-based approach to system selection

Abstract We propose a quantile-based ranking and selection (R&S) procedure for comparing a finite set of stochastic systems via simulation. Our R&S procedure uses a quantile set of the simulated probability distribution of a performance characteristic of interest that best represents the most appropriate selection criterion as the basis for comparison. Since this quantile set may represent either the downside risk, upside risk, or central tendency of the performance characteristic, the proposed approach is more flexible than the traditional mean-based approach to R&S. We first present a procedure that selects the best system from among K systems, and then we modified that procedure for the case where K − 1 systems are compared against a standard system. We present a set of experiments to highlight the flexibility of the proposed procedures.

Compressive Myelopathy Mimicking Transverse Myelitis

Spinal cord compression may be associated with a fusiform cord lesion on T2-weighted magnetic resonance imaging (MRI) images, leading to confusion with transverse myelitis and delaying effective surgical treatment. We describe 5 patients referred for evaluation of suspected neuromyelitis optica in whom the final diagnosis was symptomatic cervical spinal stenosis. The patients had gradually progressive myelopathy, with symptoms progressing over an average of 34.4 weeks. Although cervical spinal cord MRI identified long T2 hyperintense lesions, gadolinium enhancement was localized to the level of maximum spinal cord compression, in contrast to the much more extensive distribution of gadolinium enhancement characteristic of myelitis. Compressive myelopathy symptoms responded poorly to corticosteroids, but responded well to surgical decompression. Cervical cord compression due to spinal stenosis may lead to long intramedullary fusiform T2 hyperintensity on MRI, mimicking inflammatory myelopathy, but the diagnoses can be accurately distinguished by a combination of clinical and radiologic characteristics.

Smoking relapse prevention intervention: a study of postpartum women in Lodz, Poland

Approximately 30?40% of pregnant women, who smoke prior to pregnancy, tend to quit smoking by the first prenatal visit but more than half of them relapse to smoking after delivery. Interventions to maintain quitting smoking after delivery were so far rarely performed and their effectiveness is not well documented. The aim of this study was to evaluate the effectiveness of the smoking relapse prevention intervention for postpartum women. The study included 199 postpartum women (100 in the intervention group and 99 in a control group) who had quit smoking in the recent pregnancy and maintained smoking abstinence within 2 weeks after delivery (confirmed by biochemical verification). The intervention consisted of three visits conducted by midwives trained in anti-smoking intervention techniques. Women from the control group received a standard anti-smoking message. The smoking status of the study subjects was updated 6 and 12 months after delivery. The distribution of the socio-demographic characteristic of the women from the two groups did not show statistically significant differences. The women from the intervention group relapsed to smoking 12 months after delivery significantly less frequently than the women from the control group (26% vs. 56%; odds ratio = 0.28; 95% CI 0.15?0.51). The women who returned to smoking, did this later and smoked fewer cigarettes per day when they had participated in the programme.

SKEW NORMAL DISTRIBUTION AND THE DESIGN OF CONTROL CHARTS FOR AVERAGES

The paper develops two new control charts and process capability ratios based on the skew normal distribution to monitor the process average and evaluate the process capability of non-normal data. Both control charts reduce to Shewhart-type control charts when the underlying distribution of quality characteristic is symmetric. A simulation study is conducted to compare the performances of the proposed control charts with those of existing control charts. Simulation results indicate that considerable improvement over those of existing control charts can be achieved when the proposed control charts are used to monitor the process average of non-normal data. Two examples are presented for illustration.

Setup Adjustment of Multiple Lots Using a Sequential Monte Carlo Method

A new sequential Monte Carlo (SMC) adjustment method is presented for solving the machine setup adjustment problem when process parameters are unknown. In setup adjustment problems, the mean of the distribution of the quality characteristic of parts can change from lot to lot due to an improper setup operation. It is shown how a first SMC approach has performance equivalent to a recently proposed Markov chain Monte Carlo method but at a small fraction of the computational cost, allowing for on-line control. A second, modified SMC rule that avoids unnecessary adjustments that can inflate the variance is also presented. A simulation approach is presented that allows tuning of the modified SMC rule to provide robust adjustment with respect to the unknown process parameters. Applications in short-run manufacturing processes are discussed.

Proteolytic Processing of the Laminin α3 G Domain Mediates Assembly of Hemidesmosomes but Has No Role on Keratinocyte Migration

Laminin-5 (Lm5), the major adhesion ligand of basal epithelial cells, undergoes complex extracellular proteolytic processing that influences cell adhesion and migration. In tumor cell lines, the proteolytic truncation of the C-terminal G domain of the Lm alpha3 chain induces assembly of hemidesmosomes and downregulates cell migration. To define the biological functions of the alpha3 G domain processing in physiological conditions, we have expressed a series of mutant alpha3 complementary DNA in human primary alpha3-null keratinocytes immortalized by human papillomavirus E6E7 (HKalpha3 cells). Using monolayer and organotypic cell cultures we show that: (1) the hinge region between subdomains G3 and G4 carries the proteolytic cleavage sites; (2) nucleation of the hemidesmosomal proteins is independent of the proteolytic maturation of the alpha3 G domain, whereas formation of mature hemidesmosomes relies on proteolytic cleavage of alpha3; and (3) the proteolytic processing plays no role in cell migration, which suggests that nucleation of hemidesmosomal structures in culture does not reflect the migratory potential of the epithelial cells. Our results also demonstrate that HKalpha3 cells are a unique model system, which will be useful to dissect the functions and molecular interactions of Lm5.

Evaluation of Mechanical Properties and Microstructure in Ion-Irradiated Surface Layer

Target vessel materials used in spallation neutron source will be exposed to proton and neutron irradiation and mercury immersion environments. In order to evaluate the surface degradation of the vessel candidate materials due to such environment, the triple-ion beam irradiation taking the spallation reaction into account and mercury immersion tests were carried out. Mechanical properties of the gradient surface layer were evaluated by the inverse analysis with multi-layer model that considers distribution of surface characteristic was applied to the load and depth curves measured by using the instrumented indentation machine. Transmission electron microscopic observations were performed to evaluate the changes of microstructure in irradiated surface layer using focused ion-beam cut micro-specimen. The mechanical properties distributions in the surface layer were evaluated quantitatively and the changes in microstructures were correspondent to the property distribution. It was confirmed that the ductility loss is enhanced by the irradiation and mercury immersion, and simulated stress and strain curves of the ion-irradiated surface layer were adequately in good agreement with the curves of experimental equivalent neutron-irradiated material.

Transplantation of human embryonic myoblasts and bone marrow stromal cells into skeletal muscle of C57BL/10J-mdx mice.

We studied expression of dystrophin in skeletal muscles of C57BL/10J-mdx mice after transplantation of human embryonic and fetal myoblasts and bone marrow stromal cells. Dystrophin-positive areas corresponding to the location of transplanted cell were detected in muscles of all recipient mice after transplantation of different cell cultures, but the distribution of dystrophin characteristic of normal muscle fibers was detected only after transplantation of embryonic myoblasts. Dystrophin distribution in muscle fibers after transplantation of fetal myoblasts and bone marrow stromal cells was atypical.

On linear segmentation and combinatorics in co-speech gesture: A symmetry-dominance construction in Lao fish trap descriptions

Within the unified speech-with-gesture packages that we call utterances (Kendon 1972, 1980), speech and gesture play dierent roles, as deter- mined in part by intrinsically dierent semiotic properties. Co-speech representational gestures typically dier from the accompanying spoken linguistic code in displaying holistic and synthetic structuring of mean- ing, and in lacking hierarchical combinatoric properties or the linear- segmented distribution of information characteristic of spoken language (McNeill 1992: 19-23). The aim of this article is to demonstrate that co- speech gestures nevertheless can and do show combinatoric principles and linear-segmented organization. The claims I want to make are that (a) a given gesture may be structurally related, both in form and function, to a gesture in a neighboring utterance; (b) information may be segmented and supplied linearly with gestures (and not simply as a direct reflection of such linear-segmented structuring in the spoken code); and (c) multiple gestures can occur simultaneously, where the gestures show significantly dierent relationships (both semantic and pragmatic) to the utterance under way. With video-recorded data from speakers of Lao (a South- western Tai language of Laos), I document a two-phase routine that I refer to as the symmetry-dominance construction. Phase 1 is a two-handed symmetrical gesture; in the subsequent phase 2, one hand holds in posi- tion (representing given/topical/backgrounded information from phase 1), while one hand executes a new gesture (representing new/focal/ foregrounded information). This construction shows features of linear segmentation and combinatoric structure that arise from both the aor- dances and the constraints of the manual/visuospatial modality. The symbolic system of spoken language is profoundly linearized, due to severe constraints on the number of dimensions along which speech sounds may simultaneously represent information. (This relates to limi- tations in the capacity of speech sounds to bear iconic and indexical meaning; see below.) Speech phonology facilitates the construction of contrastive lexemes, and patterns of morphosyntax allow linear strings

SAGE transcript profiles of normal primary human hepatocytes expressing oncogenic hepatitis B virus X protein.

Hepatitis B virus (HBV) is a major risk factor for hepatocellular carcinoma (HCC). HBV encodes an oncogenic HBx gene that functions as a transcriptional coactivator of multiple cellular genes. To understand the role(s) of HBx in the early genesis of HCC, we systematically analyzed gene expression profiles by serial analysis of gene expression (SAGE) in freshly isolated human primary hepatocytes infected with a replication-defective adenovirus containing HBx. A total of 19,501 sequence tags (representing 1443 unique transcripts) were analyzed, which provide a distribution of a transcriptome characteristic of normal hepatocytes and a profile associated with HBx expression. Examples of the targeted genes were confirmed by the Megarray analysis with a significant correlation between quantitative SAGE and Megarray (r = 0.8, P < 0.005). In HBx-expressing hepatocytes, a total of 57 transcripts (3.9%) were induced, and 46 transcripts (3.3%) were repressed by more than fivefold. Interestingly, most of the HBx-up-regulated transcripts can be clustered into three major classes, including genes that encode ribosomal proteins, transcription factors with zinc-finger motifs, and proteins associated with protein degradation pathways. These results suggest that HBx may function as a major regulator in common cellular pathways that, in turn, regulate protein synthesis, gene transcription, and protein degradation.

Regiospecific Distribution of Highly Unsaturated Fatty Acids in Triacylglycerols of Artemia Nauplii Enriched with Marine Oils.

Brine shrimp Artemia nauplii, an important live food used in aquaculture, were enriched with five marine oil triacylglycerols (TAG) in order to enhance n-3 highly unsaturated fatty acids (HUFA) essential for fish larvae. Positional distribution of fatty acids in TAG was determined for both of the enriched Artemia nauplii and dietary marine oils. In all of the enriched Artemia nauplii, docosahexaenoic acid was preferentially located in the sn-1,3 position followed by the sn-2 position. Icosapentaenoic acid was preferentially located in the sn-2 position. Distribution patterns of these fatty acids were not similar to those in dietary TAG of fish oil origin. Positional distribution of HUFA characteristic of marine fish TAG does not appear to hold for Artemia TAG during the HUFA enrichment.

Statistical tolerance analysis for non-normal or correlated normal component characteristics

The paper presents a simple approximation technique for statistical tolerance analysis, namely, the allocation of component tolerances based on a known assembly tolerance. The technique utilizes a discretized, multivariate kernel density estimate and a simple transformation to approximate the probability distribution of the overall assembly characteristic. The data-driven approach is suitable for real-world settings in which components are randomly selected from their respective manufacturing processes to form mechanical assemblies. Demonstrated is the numerical approach in two dimensions for two distinct cases: first, when component characteristics are non-normal, independent random variables, and second, when they are highly correlated, normal random variables. The results are promising in initial test problems.

Statistical Process Control Based on Attribute Data Obtained by a Narrowed Tolerance

Process control by means of a p -chart or np -chart becomes almost impossible, if the quality level of the process in question is very good. However, if the quality characteristic is measurable then by narrowing the given tolerance limits and using accordingly changed gauges one can easily control the process by means of an attribute control chart. In this paper a method is developed to determine an optimal (in a certain sense) way to select the new narrowed tolerance tolerance limits if the distribution of the quality characteristic can be sufficiently well approximated by a normal distribution. This paper is the outcome of engineering research aiming at obtaining a useful result which can be applied at shop-floor level. A majority of modern methods (including ISO 9000 ideology) try to prevent defects by searching for defects. In contrast, the idea here is to increase sensibility of the method by defining a “high virtual defective level”, which is used for defect prevention without actually searching for defects.

The Cpk index and its confidence intervals

Introduces a practical method of constructing confidence intervals for the Cpk index. Constructs these confidence intervals based on the asymptotic normality of estimators for the sub‐indices of the Cpk index. As a result, the underlying distribution of the quality characteristic of interest need not be normal nor be known. Explains these sub‐indices and the Cp index and presents numerical examples and results of simulation studies of the confidence intervals.

Martingales, Tauberian Theorem, and Strategies of Gambling

Using the Tauberian theorem, we get an asymptotic relation between the tail of the distribution of the quadratic characteristic of a martingale and the expectation of its terminal value. In case of continuous martingales the following result is proven: if $\tau $ is a stopping time for a standard Wiener process Wt with integrable terminal value $W_\tau $, then $$ \liminf_{t\rightarrow \infty}\big(\bP\{\tau >t\}\sqrt{t}\big) \g \sqrt{\frac 2\pi }\,|\bE W_\tau | . \leqno(1) $$ Using a related result for discrete time martingales, we study asymptotic characteristics of some strategies of gambling and, in particular, Oscar's strategy.