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Spearman's Coefficient (spearman + coefficient)
Selected AbstractsSoil properties and perceived disturbance of grasslands subjected to mechanized military training: evaluation of an indexLAND DEGRADATION AND DEVELOPMENT, Issue 3 2007D. P. Althoff Abstract Mechanized maneuver training impacts the landscape by creating depressions, compacting soils, producing bare ground areas, transporting seeds of invasive plants, and crushing vegetation. We measured 3 physical, 13 chemical, and 2 biological soil properties and used a disturbance index (DI) based on perceptions of soil conditions on a military installation to assess the condition of 100,×,100,m plots (1 ha): 10 in 2002 and 10 in 2004. Potential DI scores range from 0 (no appreciable evidence of disturbance) to 1 (>95 per cent of the plot disturbed). Bulk density, porosity (%), and water content (%),all at 5·1,10·0,cm depth, and nematode family richness (NFR) were significantly, negatively correlated (Spearman coefficients, rs) with the DI of both years. The strong negative correlation (rs,=,,0·69 in 2002, ,0·79 in 2004) of NFR with the DI appears to reflect the status of nematode diversity and, therefore, may serve as a useful, inexpensive approach to rapidly assessing grasslands subjected to mechanized military training. Copyright © 2007 John Wiley & Sons, Ltd. [source] ORIGINAL ARTICLE: Comparative Analysis of Peripheral Natural Killer Cells in the Two Phases of the Ovarian CycleAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 1 2010Ageliki Pantazi Problem Changes in endometrial Natural Killer (NK) cells during the luteal phase of the ovarian cycle are important in initiating/maintaining a subsequent pregnancy. In the present study it was investigated whether during the menstrual cycle changes occur also in peripheral blood (PB) NKs. Method of study Blood samples during the follicular and the luteal phase were collected from 30 women without fertility problems. Samples were analyzed by flow-cytometry for: (1) NK cells (CD3,CD16+CD56+) and (2) intracellular production of interferon-, (IFN-,) by NK cells. For the comparison and correlation of the two populations between the two phases, Wilcoxon signed-rank test and Spearman's Coefficient were used. Results The differences in percentages of CD3,CD16+CD56+ cells and that of CD3,CD16+CD56+/IFN-,+ cells between the follicular and the luteal phase were not statistically significant (10.61 ± 5.11 versus 9.76 ± 4.57 and 6.48 ± 7.90 versus 7.30 ± 6.77, respectively, P > 0.05). The correlation between the two variables (NK% and NK/IFN-,%) was weakly positive (P = 0.07) only in the follicular phase. Conclusion The study did not reveal menstrual cycle-depended changes in PB NK cells. Thus, a suggestion to measure these cells in a specific phase of the cycle in order to predict the outcome of a subsequent pregnancy in women with fertility problems is objected. [source] A field validation of two sediment-amphipod toxicity testsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2002Steven P. Perraro Abstract A field validation study of two sediment-amphipod toxicity tests was conducted using sediment samples collected subtidally in the vicinity of a polycyclic aromatic hydrocarbon (PAH)-contaminated Superfund site in Elliott Bay (WA, USA). Sediment samples were collected at 30 stations with a 0.1 m2 grab from which subsamples were taken for sediment toxicity testing and geochemical and macrofaunal analyses. Standard 10-d sediment-amphipod toxicity tests were conducted with Rhepoxynius abronius and Leptocheirus plumulosus. Sediments were analyzed for 33 PAHs, pentachlorophenol, polychlorinated biphenyls, acid-volatile sulfide, simultaneously extracted metals (Cd, Cu, Zn, Pb, Ni), total organic carbon, and grain size. Sediment temperature, oxygen-reduction potential, water depth, and interstitial water salinity were also measured. Polycyclic aromatic hydrocarbons, quantified as total PAH toxic units (TUPAH), were confirmed to be an important common causal agent of the changes in the two toxicity test (% survival R. abronius, % survival L. plumulosus) and five macrofaunal community (number of species, S; numerical abundance, A; total biomass, B; Swartz's dominance index, SDI; Brillouin's index, H) endpoints. Two other macrofaunal community metrics (the complement of Simpson's index, 1 , SI, and McIntosh's index, MI) were less sensitive to TUPAH than the two toxicity test endpoints. The sensitivities of R. abronius and L. plumulosus to TUPAH were statistically indistinguishable. Field validations were conducted by testing the association between or among each toxicity test endpoint, each of seven macrofaunal community metrics (S, A, B, SDI, H, 1 , SI, MI), and TUPAH by (1) Spearman's coefficient of rank correlation, (2) Kendall's coefficient of concordance, (3) G tests of independence, and (4) regression analysis. Some field validations based on multivariable tests of association (e.g., points 2 and 3) among toxicity test, field, and stressor endpoints produced false positive results. Both toxicity test endpoints were validated as indicators of changes in S, A, SDI, and H by all the methods tested. The resolution power of the relationships between the laboratory toxicity test and macrofaunal field endpoints was low (, three classes) but sufficient to discriminate ecologically important effects. We conclude that standard sediment-amphipod toxicity tests are ecologically relevant and that, under the proper conditions, their results can be used for lab-to-field extrapolation. [source] Influence of climatic factors in the incidence of multiple sclerosis relapses in a Portuguese populationEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2009A. C. Fonseca Background and purpose:, Environmental factors are thought to be important in multiple sclerosis (MS) pathophysiology. We aimed to evaluate if there was an association between MS relapses and some climatic factors in a Portuguese population. Methods:, Four year retrospective study analyzing 414 MS relapses in 249 consecutive relapsing,remitting patients. Non-parametric statistics were used to compare the distribution of relapses across months and seasons. Spearman's coefficient was determined to evaluate the correlation between relapses frequency and maximum and minimum atmospheric temperatures, humidity and atmospheric pressure. Results:, The mean number of relapses was not significantly different between months or seasons. No correlation was found between relapse frequency and any climatic factor. Conclusion:, Our series is one of the largest addressing the influence of specific climatic factors on MS relapses. The number of clinical MS relapses seems to be unrelated to climatic factors. [source] Ability of Patients to Accurately Recall the Severity of Acute Painful EventsACADEMIC EMERGENCY MEDICINE, Issue 3 2001Adam J. Singer MD Abstract. Objective: Pain studies require prospective patient enrollment to ensure accurate pain assessment. The authors correlated pain assessments of an acute painful episode over a one-week period and determined the accuracy of patient pain severity recall over time. Methods: This was a prospective, descriptive, longitudinal study. Participants were a convenience sample of 50 emergency department patients with acute pain resulting from injuries or painful invasive procedures. A trained research assistant administered a structured pain survey containing demographic and historical features to all patients. Patients sequentially assessed their pain severity using a vertical 100-mm visual analog scale marked "most pain" at the top, a verbal numeric rating scale ranging from 0 to 100 from none to worst (NRS100), and a verbal numeric rating scale ranging from 0 to 10 from none to worst (NRS10). Patients were contacted by phone and asked to reassess their initial pain severity one and seven days later using the two verbal numeric rating scales. Analysis of pain assessments using the various scales at the three time intervals was performed with Pearson's and Spearman's coefficients and repeated-measures analysis of variance (ANOVA). Results: There were 50 patients with a mean age of 41 years. Correlation between initial pain assessments on the three scales ranged from 0.83 to 0.92. Correlations between the initial and 24-hour assessments were NRS100-0.98 and NRS10-0.98. Correlations between the initial and one-week assessments were NRS100-0.96 and NRS10-0.97. Repeated-measures ANOVA showed no significant change in pain assessments over time for both verbal numeric scales. Conclusions: Pain severity assessments of acute painful events one and seven days later were similar and highly correlated with initial assessments using both verbal numeric scales. Patients accurately recall the severity of an acute painful episode for at least one week after its occurrence, which may allow retrospective pain assessments. [source] | ||||||||||