With the advent of electronics technology, various instruments in surface roughness measurements appear sequentially. Errors and erroneous judgment will happen while using unsuitably, due to the operating method and range are not exactly the same. For stylus profilometer, the effects of operating parameters on surface roughness of standard sample and machined elements are presented. Furthermore, small size elements or mirror-like surfaces are measured by scanning electron microscope (SEM) and atomic force microscope (AFM). Experimental results show that the cut-off value is the most significant parameter to Ra, it suggests that the best range for the cut-off value is greater and equal to 0.8mm. The error of Rmax is less than 3% at scanning speed of 0.05, 0.1 and 0.5mm/s, and that within 10% at scanning speed of 2mm/s. Rmax increases with increasing angle of work-stage. The measurement length for standard sample is insignificant to Ra and Rmax. When the surface with curvature is measured, the curvature is removed by the cut-off value for filtering, and the roughness curve is judged whether include peaks and valleys of profile curve, and then the surface roughness is measured by man-made. When the irregular surface is measured, the cut-off value of 0.8mm and higher is selected, and represented surface in the way of separate section or area. SEM and AFM are used to assist in measuring for real roughness value when small size elements or mirror-like surfaces are measured. Variations of roughness of machined elements in polishing are measured finally, results show that Ra, Rq, Rmax, Rz, Skewness will decrease with increasing polishing time, and Kurtosis will increase.

Background: Clinical breakpoints and epidemiological cut-off values for N. gonorrhoeae azithromycin antimicrobial susceptibility testing have not been established. This study utilized existing minimum inhibitory concentration (MIC) data from CDC’s Gonococcal Isolate Surveillance Project (GISP) to establish epidemiological cut-off values for azithromycin and N. gonorrhoeae as determined by agar dilution. Methods: MIC distributions for the pooled dataset and each data year (2005-2012) were constructed. Epidemiological cut-off values were calculated using two methods. Method 1 considers the wild-type MIC distribution, the modal MIC for the distribution, and the inherent variability of the test (±1 twofold-dilution). Method 2 defines the epidemiological cut-off value as two twofold-dilutions higher than the MIC50. Results: Taking into consideration the wild-type MIC distributions and the inherent variability of the test, the epidemiological cut-off value chosen for the pooled dataset and each data year using Method 1 was ≤1.0 µg/mL. The MIC50 for the pooled dataset and each data year was 0.25 µg/mL. Two twofold-dilutions higher than the MIC50 (0.25 µg/mL) for the pooled dataset and each data year was 1.0 µg/mL. Discussion: The epidemiological cut-off values chosen using Methods 1 and 2 (≤1.0 µg/mL) were identical for the pooled dataset and each data year, indicating the epidemiological cut-off value has not changed from 2005-2012. The epidemiological cut-off value for N. gonorrhoeae azithromycin agar dilution antimicrobial susceptibility testing established during this study can be used to help set clinical breakpoints and identify isolates with reduced susceptibility to azithromycin.

Akut- och psykiatriska avdelningar på länssjukhuset Ryhov i Jönköping använder sig av snabbtest för drogscreening med varierande kvalitet under de tider då analysinstrumentet Konelab Prime 30i inte är bemannat. Syftet med studien var att utvärdera sensitivitet och specificitet hos Multitest 15 från tillverkaren Acro Biotech, och jämföra resultat från två olika avläsningstider. Antalet urinprover som samlades in för analys uppgick till 272. Positiva och negativa urinprover med drogkoncentrationer inom ±50% från varje drogs gränsvärde insamlades. Senare inkluderades drogkoncentrationer utanför detta intervall. Proverna testades med Multitest 15 vid laboratoriet för klinisk kemi på Ryhov efter utförd analys med Konelab Prime 30i, vars analysresultat utgjorde referens. De droger som testades var amfetamin, metamfetamin, ecstasy, bensodiazepiner, buprenorfin, kokain, metadon, morfin, THC, oxykodon och tramadol. För alla droger sammantaget var sensitiviteten 86,7% - 100%, specificiteten 33,3% - 100% och träffsäkerheten 71,4% - 94,7%. Provurvalet inom intervallet ±50% från gränsvärdet var begränsat, vilket avsevärt påverkat dessa beräkningar, och Konelab Prime 30i använder semikvantitativ metod vilken endast ger approximativa koncentrationsvärden som referens. / The emergency and psychiatric wards on the county hospital Ryhov in Jönköping utilize onsite drug testing with varying quality during evenings and night-time when no staff are operating the chemistry analyzer Konelab Prime 30i. The aim of the study is to evaluate the performance of sensitivity and specificity of Acro Biotech Multitest 15 and comparing results from two different reading-times. The number of urine samples collected for analysis was 272. Positive and negative urine samples with drug concentrations within ± 50% from cut-off were collected. Later, concentrations outside of this range was included. The samples were tested with Multitest 15 at the laboratory for clinical chemistry at Ryhov after analysis with Konelab Prime 30i providing reference results. The drugs tested were amphetamine, methamphetamine, ecstasy, benzodiazepines, buprenorphine, cocaine, methadone, morphine, THC, oxycodone and tramadol. All drugs included, the sensitivity was 86.7% - 100%, the specificity 33% - 100% and the accuracy 71.4% - 94.7%. The sample selection within the range ±50% from the cut-off value was limited, which significantly affected these calculations, and Konelab Prime 30i uses a semi-quantitative method only providing approximate concentration values for reference.