Sites standard deviation

Values are given as mean concentrations. The ranges are given in parentheses unless otherwise noted. Values at three different sites Standard deviation Values for three sites... 

Field Tests. Recently we conducted a field test at a site contaminated with fuel oil. Our measurements were 0.0625 0.0212 mA for the well water and 0.0189 0.0119 mA for distilled water (showing errors of one standard deviation). From calibration curves, these numbers can be reported as equivalent to 50 ppb phenol or 34 ppb xylenes. Nine-month-old laboratory results (EPA method 624 and GC/FID) for this site indicated concentrations of 25 ppb for benzene, toluene, and xylenes combined and 100 ppb for fuel oil. The important result is the significant difference between the distilled-water and well-water measurements. We are very encouraged by these results and are planning future field tests. 

Figure 2.3. Carbon and nitrogen isotope values of human bone collagen at Maya sites in Belize. The value for the modem sample has been corrected for collagen-hair spacing and the Industrial Effect. Boxes represent isotopic means one standard deviation.

Figure 3.2. 8 C values of fossil browser apatites plotted against age for sites including Die Kelders, Klasies River Mouth I, Sterkfontein and Makapansgat. Enamel is represented by solid squares, bone apatite by solid circles. The mean value standard deviation for modem browsers, represented by dashed lines, has been shifted by +1.5%o as described in the text. Adapted from Lee-Thorp and van der Merwe (1987).

Figure 5.5. Summarized 6 C data Tor browsers and grazers, expressed as dark shaded and cross-hatched boxes, respectively, incorporating means and standard deviations, from the three groups of sites plotted against time (a) Die Kelders and Swartkrans, (b) Klasies and Makapansgat, and (c) Border Cave. Typical matrix values are shown as light shaded rectangles.

An estimate of the value of a sample at any sample site. An estimate of standard deviation at any sample site. 

Fig. 4.3. (A) Composite multispecies benthic foraminiferal Mg/Ca records from three deep-sea sites DSDP Site 573, ODP Site 926, and ODP Site 689. (B) Species-adjusted Mg/Ca data. Error bars represent standard deviations of the means where more than one species was present in a sample. The smoothed curve through the data represents a 15% weighted average. (C) Mg temperature record obtained by applying a Mg calibration to the record in (B). Broken line indicates temperatures calculated from the record assuming an ice-free world. Blue areas indicate periods of substantial ice-sheet growth determined from the S 0 record in conjunction with the Mg temperature. (D) Cenozoic composite benthic foraminiferal S 0 record based on Atlantic cores and normalized to Cibicidoides spp. Vertical dashed line indicates probable existence of ice sheets as estimated by (2). 3w, seawater S 0. (E) Estimated variation in 8 0 composition of seawater, a measure of global ice volume, calculated by substituting Mg temperatures and benthic 8 0 data into the 8 0 paleotemperature equation (Lear et al., 2000).

Figure 6.2 Critical parameters of the miR/mRNA co-transfection method. (A) Titration of mRNA amount. HeLa cells were transfected with increasing amounts of cap tail R-luc-4 sites mRNA and a fixed amount of firefly (F-luc) mRNA. R-luc expression (luciferase activity) was measured 5 h after transfection. (B) Titration of miCXCR4 concentration. HeLa cells were transfected with cap tail R-luc-4 sites mRNA, F-luc mRNA, and varying concentrations of miCXCR4. Luciferase activity was measured 16 h after transfection and fold-repression by the miR was calculated as in Fig. 6.1D (C) Time-course of miR-mediated repression. HeLa cells were co-transfected with cap tail R-luc-4 sites and F-luc (control) mRNAs, either with or without miCXCR4, and harvested at different time points. Repression was calculated as detailed in Fig. 6.1 and plotted against time (mRNA transfection data series depicted by the circles). Analogous plasmid DNA transfections are shown for reference (pDNA, diamonds). Averaged results from several experiments are shown with standard deviation. Data were previously published (Humphreys etal., 2005). Copyright PNAS, reprinted with permission.

Site Activity median diameter (jam) geometric standard deviation... 

In this example, of transfer of a drug product dissolution method, the samples are independent (as test is destructive in nature) and additional variability due to different baths/standard sets are assumed to be negligible (dissolution baths were independently calibrated as per USP criteria). Based on the receiving site s familiarity with the methodology to be transferred, only one analyst/dissolution bath per site was used. The analyses were performed at USP level 2, i.e. 12 individual samples were tested. The standard deviation on 12 replicate analyses from an earlier study was 3.02 (Borman et al., 2009). The authors indicated that as this estimate is based on a limited number of replicates, it was good practice to use a pre-defined multiplier, which allows for uncertainty (Hahn and Meeker, 1991), in this case 1.255 (multiplier for... 

Second-order rate constants for MTSEA-, MTSET-, and MTSES-modification of residues within the loop D region of the GABA-binding site. Second-order rate constants (IC2) represent the mean standard deviation. NR, no reaction. The free solution rates were reported by Karlin and Akabas (1998) and reflect the rates of MTS reaction with 2-mercaptoethanol. Adapted from Holden and Czajkowski (2002) with permission from the American Society of Biochemistry and Molecular Biology... 

Due to the surface roughness, the reacting particle has greater probability to react at the surfaee sites, which are at the top causes heterogeneity in the reaetion probability distribution. This heterogeneity can be estimated by standard deviation of P(x,y,h t) as. 

In this example, the likelihood function is the distribution on the average of a random sample of log-transformed tissue residue concentrations. One could assume that this likelihood function is normal, with standard deviation equal to the standard deviation of the log-transformed concentrations divided by the square root of the sample size. The likelihood function assumes that a given average log-tissue residue prediction is the true site-specific mean. The mathematical form of this likelihood function is... 

Several investigators reported the presence of nickel concentrations in rain. The annual mean nickel concentration in precipitation at Lewes, Delaware, was 0.79 pg/L (Barrie et al. 1987). The mean concentration ( standard deviation) of nickel collected from rain showers in southern Ontario, Canada, in 1982 was 0.56 0.07 pg/L (Chan et al. 1986). The mean concentrations in northern and central Ontario were both 0.61 pg/L, indicating a lack of spatial variability. Sudbury, the site of a large nickel smelter, is located in central Ontario. Nickel concentrations from rain samples collected at four sites in Sweden had a mean range of 0.017-0.51 pg/L (Hansson et al 1988). 

Effect of Dust Storm Episodes on the Average Weekly Aerosol Concentrations. The total and fine gravimetric mass averaged over all sites for each week, is depicted in Figure 6. The error bars for the Owens Valley curves represent the standard deviation of the mean. The errors on the Mono Lake curve represent the sampling system error of 15%. The mean weekly values do not include the three dust storm episodes sampled separately, but do include several additional dust storms. Table I lists all the dust storms reported by the sampler operators. 

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