81 research outputs found
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Some Distributional Facts about Fricatives and a Perceptual Explanation
Across and within languages voiced sibilants tend to be disfavored relative to voiceless ones. This paper explores the claim that voicing more adversely affects the distinctive acoustic properties of sibilants than those of nonsibilants. One prediction associated with this claim is that voicing differentially lowers the amplitude of frication noise for sibilants and non-sibiliants so that amplitude differences between the two classes are reduced. Acoustic measurements confirm this prediction. A second prediction is that voicing has a greater negative effect on the identification of sibilants than nonsibilants. Perceptual results from this and previous studies are somewhat variable, but averaged data support this prediction. The findings suggest that voiced sibilants are disfavored in part for perceptual reasons
Presenting medical statistics from proposal to publication
Designed for researchers presenting medical statistics for publication, this guide emphasises the principles of good presentation through examples. It contains tips, information boxes and figures, as well as references for the statistical methods used. It also presents the different stages of the research process
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Chronic sacral nerve stimulation as a novel treatment for stress urinary incontinence-A rat model
We propose an animal model to evaluate the effect of chronic sacral nerve stimulation (SNS) on surgically induced intrinsic sphincter deficiency (ISD) secondary to transabdominal urethrolysis (U-Lys).
Twenty-five 6-week old virgin female Sprague-Dawley rats were divided into four groups: control (CTRL), U-Lys only, SNS only, and both (U-Lys/SNS). Groups CTRL (N = 5) and U-Lys only (N = 5) were maintained in the animal research facility in standard fashion for 2 weeks. Groups SNS only (N = 5) and U-Lys/SNS (N = 10) underwent chronic SNS for 6 continuous hours daily for 2 weeks. Retrograde leak point pressure (RLPP) was measured at baseline and at 2 weeks following observation or treatment. Five consecutive RLPP measurements were averaged per measurement cycle. SAS 9.3 was used to evaluate means and standard deviation.
Baseline mean RLPP was 65 mmHg. The U-Lys only group mean RLPP at initial urethrolysis (58 mmHg) decreased (31 mmHg, P < 0.0001) after 2 weeks of observation. In the SNS only group, mean RLPP significantly increased from baseline (73 mmHg) after 2 weeks of chronic SNS stimulation (80 mmHg, P < 0.01). In rats that underwent both U-Lys and SNS stimulation mean RLPP was initially low (46 mmHg) after U-Lys and then significantly increased after 2 weeks of SNS (65 mmHg, P < 0.0001).
Chronic SNS mediates an improvement in urethral sphincteric function at stimulation parameters similar to those used in humans for treating voiding dysfunction. SNS increased urethral resistance in rats with and without surgically induced ISD
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Cancer Data Visualization: Developing Tools to Serve the Needs of Diverse Stakeholders
Purpose of review To describe how cancer data visualization tools can catalyze novel research and inform local cancer control planning. Recent findings In recent years, cancer centers across the nation have increasingly embraced geospatial tools to respond to the unique distributions of disease and multilevel risk factors within their catchment areas. Sylvester Comprehensive Cancer Center in Miami, Florida, recently developed a publicly available, interactive, web-based cancer data visualization tool called SCAN360. Using SCAN360 as an example, we discuss key considerations and challenges for the development of cancer data visualization tools that serve the needs of stakeholders in community, academic and government settings. Cancer data visualization tools are useful for stakeholders from diverse sectors and may facilitate a range of cancer control efforts, from identifying regions for targeted outreach and engagement, to informing the allocation of resources for government and community initiatives, and motivating collaborative, interdisciplinary cancer research
Detection of Disease Genes by Use of Family Data. II. Application to Nuclear Families
Two likelihood-based score statistics are used to detect association between a disease and a single diallelic polymorphism, on the basis of data from arbitrary types of nuclear families. The first statistic, the nonfounder statistic, extends the transmission/disequilibrium test to accommodate affected and unaffected offspring and missing parental genotypes. The second statistic, the founder statistic, compares observed or inferred parental genotypes with those of some reference population. In this comparison, the genotypes of affected parents or of those with many affected offspring are weighted more heavily than are the genotypes of unaffected parents or of those with few affected offspring. Genotypes of single unrelated cases and controls can be included in this analysis. We illustrate the two statistics by applying them to data on a polymorphism of the SDR5A2 gene in nuclear families with multiple cases of prostate cancer. We also use simulations to compare the power of the nonfounder statistic with that of the score statistic, on the basis of the conditional logistic regression of offspring genotypes
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Test-Retest Reliability of Thermal Temporal Summation Using an Individualized Protocol
Temporal summation (TS) refers to the increased perception of pain with repetitive noxious stimuli. It is a behavioral correlate of wind-up, the spinal facilitation of recurring C-fiber stimulation. In order to utilize TS in clinical pain research, it is important to characterize TS in a wide range of individuals and to establish its test-retest reliability. Building on a fixed-parameter protocol, we developed an individually adjusted protocol to broadly capture thermally generated TS. We then examined the test-retest reliability of TS within-day (intertrial intervals ranging from 2 to 30 minutes) and between-days (intersession interval of 7 days). We generated TS-like effects in 19 of the 21 participants. Strong correlations were observed across all trials over both days (intraclass correlation [ICC] [A, 10] = .97, 95% confidence level [CL] = .94–.99) and across the initial trials between days (ICC [A, 1] = .83, 95% CL = .58–.93). Repeated measures mixed-effects modeling demonstrated no significant within-day variation and only a small (5 out of 100 points) between-day variation. Finally, a Bland-Altman analysis suggested that TS is reliable across the range of observed scores. Without intervention, thermally-generated TS is generally stable within day and between days.
Our study introduces a new strategy to generate thermal TS in a high proportion of individuals. This study confirms the test-retest reliability of thermal TS, supporting its use as a consistent behavioral correlate of central nociceptive facilitation
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QTc prolongation in children following congenital cardiac disease surgery
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Histologic types of epithelial ovarian cancer: have they different risk factors?
The histologic types of epithelial ovarian cancer differ in clinical behavior, descriptive epidemiology, and genetic origins. The goals of the current study were to characterize further the relation of histologic-specific ovarian cancer risks to reproductive and lifestyle attributes.
The authors conducted a pooled analysis of 10 case-control studies of ovarian cancer in US White women, involving 1834 patients with invasive epithelial ovarian cancer (1067 serous, 254 mucinous, 373 endometrioid, and 140 clear cell) and 7484 control women.
Risks of all four histological types were inversely associated with parity and oral contraceptive use, but the histologic types showed different associations with nonreproductive factors. Unique associations include an inverse relation of serous cancer risk to body mass index, a positive relation of mucinous cancer risk to cigarette smoking, and a weakly positive relation of endometrioid cancer risk to body mass index. Risk of all histologic types was unassociated with age at menarche, age at menopause, a history of infertility, noncontraceptive estrogen use, and alcohol consumption.
The most important modifiers of ovarian cancer risk (parity and oral contraceptive use) showed similar associations across the histologies. Nevertheless, the unique associations seen for other modifiers support the conjecture that the histologic types of epithelial ovarian cancer have different etiologies, which should be addressed in future investigations of the molecular basis of ovarian cancers and their responses to therapies
Diagnostic discrepancies between second-opinion and referring pathology reports of neuroendocrine tumors.
e15011 Background: The nomenclature and histologic classification schemes for neuroendocrine tumors (NETs) have historically been heterogeneous and inconsistent. However, clinicians require specific descriptors to determine treatment plans for patients. In 2010, Klimstra, et al. published a set of NET pathology reporting guidelines. Using these guidelines, we undertook a systematic evaluation of discrepancies between referring versus Stanford second-opinion NET pathology reports. Methods: We developed a cohort ofall NET cases seen at Stanford University Hospital between April 1998 and December 2012 with available Stanford and referring pathology reports for the same specimen to identify the discrepancies between their clinical diagnoses. Results: Of 170 cases, histological diagnoses were discrepant in 79% of the reports; 89 (66%) of which were clinically insignificant, and 46 (34%) clinically significant. Stanford used 14 unique terms for histological description, and referring institutions used 49 unique terms. Grade, mitotic index (MI), and Ki67 were among the variables examined; they were not reported (NR) from the majority of cases in one or both reports, yet more likely to be included in the Stanford report. Grade was NR in one or both reports in 152 cases (89%); of the 18 cases reporting grade in both reports, 3 (2%) were discrepant. MI was NR in one or both reports in 128 cases (75%); of the 42 cases reporting MI in both reports, 27 (16%) were discrepant. Ki67 was NR in one or both reports in 153 cases (90%); of the 17 cases reporting Ki67 in both reports, 12 (7%) were discrepant. Reporting was found to improve over time for these variables (five-year blocks from 1998-2012). There was a trend towards improved reporting from academic hospitals (vs. non-academic hospitals) and by Stanford NET pathology experts (vs. general pathologists). Conclusions: Clinically relevant differences were frequently found between Stanford and referring pathology reports for NETs. Future studies of NET pathology discrepancies are warranted to allow additional time for adoption of the 2010 guidelines
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