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We present a method for the evaluation of fluorescence fluctuations on the basis of Mandel's Q parameter, using sampling time-dependent factorial cumulants. By relating the Q parameter to the sampling time, we obtain the mean single molecule rate (mSMR), an easy to interpret expression that provides both brightness and diffusion information. The model is suitable for the widely used confocal setups with single photon excitation and a single detection channel. We present a way to correct the mSMR for afterpulsing, dead time and background noise. To account for photokinetic effects at short sampling times, we expand the model by a simple on/off isomerization term, which is similar to the well-known triplet model. The functionality of the mSMR is shown using Monte Carlo simulations. The correction mechanisms and the experimental applicability of the model are then demonstrated by DNA measurements of defined composition. By systematically analyzing DNA mixtures, we can show that at large sampling times, the mSMR correctly describes the single molecule brightness rates and the diffusive properties of DNA molecules. At short sampling times, the photokinetic effects of isomerization are accurately described by the mSMR model. Since additionally the mSMR can easily be corrected for measurement artefacts such as detector dead time, afterpulsing and background noise, this is a valuable advantage over the standard method of fluorescence correlation spectroscopy.

BACKGROUND: The use of opioids for the treatment of pain is a risk versus benefit analysis and metabolic disease is an often overlooked variable in the equation and may lead to increased risk of comorbidities of cardiovascular and cerebrovascular disease and diabetes. OBJECTIVES: Our objective was to identify and describe abnormalities among the comprehensive metabolic and lipid panels of individuals taking prescription opioids. STUDY DESIGN: We performed a cross-sectional study of the laboratory values with 3 cycles (2011–2016) of the National Health and Nutrition Examination Survey (NHANES) in March 2020. SETTING: NHANES sampling is conducted using a multistaged, stratified, cluster sampling technique to create a representative sample of the United States. METHODS: We excluded patients with histories of cancer and under the age of 25 years. Our final sample size was 11,061 (n = 162,547,635), with 797 reportedly using a prescription opioid in the past 30 days—a weighted percent representing 22.95% of the US population. Our analyses identified mean differences in biomarkers between individuals taking prescription opioids and the US population. RESULTS: Laboratory values from the comprehensive metabolic panel were all within reference ranges for both groups, with only bilirubin levels being statistically lower in the group currently taking prescription opioids. Values from the lipid panel of both the opioid using and comparison groups were above reference range for total cholesterol and fasting glucose. The opioid using group was also higher than the reference range for triglycerides (mean [M] = 165.4, standard deviation [SD] = 14.2) and insulin (M = 15.5, SD = 2.2), whereas the comparison group was not. The oral glucose measure was within normal ranges for both groups; however, the opioid using group was 13.7 points higher than the comparison group (M = 122.3, SD = 1.8; M = 108.6, SD = 4.0; P < 0.01). LIMITATIONS: While our study uses a large sample for a robust generalizable analysis it is a correlation study and a longitudinal cohort would provide better evidence linking potential disease states to prescription opioid use. CONCLUSIONS: Although all Americans should be alarmed at the lipid levels reported in this study, specific combinations of heightened lipid laboratory values among prescription opioid users accelerate the trajectories toward comorbidities—heart disease, cerebrovascular disease, and diabetes—leading to diminished quality of life. Therefore pain management and comprehensive drug recovery programs should include nutritional counseling and physical activity as part of their overall treatment plan.

Determining the concentration of nucleic acids in biological samples precisely and reliably still is a challenge. In particular when only very small sample quantities are available for analysis, the established fluorescence-based methods give insufficient results. Photobleaching is seen as the main reason for this. In this paper we present a method to correct for the photobleaching effect. Using confocal microscopy with single molecule sensitivity, we derived calibration curves from DNA solutions with defined fragment length. We analyzed dilution series over a wide range of concentrations (1 pg/ml-1000 pg/ml) and measured their specific diffusion coefficients employing fluorescence correlation spectroscopy. Using this information, we corrected the measured fluorescence intensity of the calibration solutions for photobleaching effects. We evaluated our method by analyzing a series of DNA mixtures of varying composition. For fragments smaller than 1000 bp, our method allows to determine sample concentrations with high precision in very small sample quantities (< 2 ml with concentrations < 20 pg/ml). Once the technical parameters are determined and remain stable in an established process, our improved calibration method will make measuring molecular biological samples of unknown sequence composition more efficient, accurate and sample-saving than previous methods.

Eine neue Fluoreszenz-Fluktuations-spektroskopische Methode vereint die Vorzüge der Fluoreszenz-Korrelations-Spektroskopie mit denen helligkeitsbasierter Verfahren für hochpräzise Untersuchungen dynamischer biomolekularer Prozesse. Dieser Artikel stellt wesentliche Eigenschaften dieser neuen Methode vor.

Hintergrund: Fährschiffsunglücke auf der Ostsee; abhängig von der Position auf See hohe Todesrate oder vollständige Evaquierung ohne Opfer immer mit Verlust der Rettungsplattform. Methoden: Analyse von Ursachen und Risiken bei Schiffsbränden in Abhängigkeit von Besatzungsstärke,[for full text, please go to the a.m. URL], DAV 2011; 29. Jahrestagung der Deutschsprachigen Arbeitsgemeinschaft für Verbrennungsbehandlung

International audience

International audience

International audience

International audience

OBJECTIVE: A growing body of literature is documenting the health effects of racial discrimination. The authors investigated the association between racial discrimination and alcohol-related behavior in a sample of urban transit operators. METHODS: Using data from a 1993-1995 cross-sectional study of transit operators in San Francisco, California, the authors analyzed responses to two sets of questions about racial discrimination; the first set focused on reaction to unfair treatment and the second on arenas, or domains, of discrimination. Alcohol-related variables were: number of drinks per month, heavy drinking, alcohol dependence, and negative consequences of alcohol consumption. RESULTS: Operators who reported five or more domains of discrimination drank an average of 13.4 more drinks per month than those who reported no domains of discrimination (P = 0.01). Similarly, they were more likely to be heavy drinkers (adjusted odds ratio [OR] = 2.16; 95% confidence interval [CI] 1.14, 4.09) and dependent on alcohol (adjusted OR = 2.02; 95% CI 1.08, 3.79) than operators who reported no domains of discrimination. The number of domains in which operators reported having experienced discrimination was not related to sex, age, household income, job seniority, or marital status, but varied significantly by educational level and race/ethnicity. CONCLUSIONS: Data from a sample of urban transit operators showed an association between the number of domains of discrimination and some alcohol-related outcomes, but not others.

Investigations of different composites, microfilled resins and amalgam in simulation tests show that the abrasion by food will be negligible compared with other abrasion mechanism.

In dieser in vitro-Untersuchung wurde mittels rasterelektronenmikroskopischer Aufnahmen die Oberflächenstruktur verschiedener Composites, dreier hochglanzpolierbarer Materialien und eines Amalgams miteinander verglichen, nachdem sie durch drei unterschiedliche Abrasionsmethoden abradiert worden sind. Der Abrieb durch Zähneputzen, durch Antagonistenkontakt und durch die Nahrung sollte simuliert werden. Beim Bürstenabrieb wurde bei den Composites beobachtet, daß nur die Matrix durch die Putzkörper der Paste abgetragen wird, so daß die Füllkörper freigelegt werden. Diese werden dann bei nur noch geringer Verankerung in der Matrix durch die Borsten herausgebrochen. Durch die relativ großen Füllkörper ergibt sich hierdurch eine sehr rauhe Oberfläche. Bei den drei hochglanzpolierbaren Materialien wie auch beim Amalgam bleibt dagegen die Oberfläche glatt wie zu Beginn. Die Antagonistenabrasion zeigte, daß bei den herkömmlichen Composites die Füllkörper plan abgeschliffen werden. Zwischen dies en planen Partikeln werden Matrixteile und kleinere Zuschläge herausgerissen, Amalgam hat dagegen eine ähnlich glatte Oberflächenstruktur wie bei den Zahnbürstenversuchen. Bei der Simulation der Abrasion durch die Nahrung wurde festgestellt, daß der Materialverlust gegenüber den beiden anderen Mechanismen zu vernachlässigen ist. Bei den Composites wird nur die oberste füllkörperfreie Schicht abgetragen, so daß dann gerade die Spitzen der ersten Partikel zu sehen sind.

The objectives of this study were to assess the feasibility of administering the CHecklist for Autism in Toddlers (CHAT) at the 18-month developmental check, estimate the prevalence of screening positive for autism at the first and second administrations of the CHAT and estimate the prevalence of diagnosed cases of autism. A cross-sectional study design was utilised and data was collected at child developmental screening clinics in counties Cork and Kerry. The sample group consisted of infants attending the routine 18-month developmental assessment, who were broadly representative of infants in the catchment area. The main outcome measure was a medium or high-risk score following two administrations of the CHAT screening instrument and a positive diagnosis of autism after clinical assessment. The CHAT was administered to 2117 infants (79% of those approached) of whom 29 were scored at medium or high risk at first screening, resulting in a prevalence rate of 137 per 10,000 (95% CI: 87-187). A total of 7 of the 29 first screen positive infants were positive (medium or high risk) at second screening, 12 were low risk and 10 parents refused to participate. On subsequent clinical assessment of the 7 infants screening positive on first and second assessment and assessment of 5 of the 10 infants whose parents declined second screening, 7 children received a diagnosis of autism. Thus the overall prevalence of clinically diagnosed autism following this screening exercise was 33.1 per 10,000 (95% CI: 13.3 to 68.0). The CHAT instrument is a useful tool to help identify childhood autism among infants. Routine use of this instrument at 18-month developmental assessment merits consideration.

In this paper we present a noncooperative game theoretical model for the well known problem of experimental design. A virtual player decides the design variables of an experiment and all the players solve a Nash equilibrium problem by optimizing suitable payoff functions. We consider the case where the design variables are the coordinates of n points in a region of the plane and we look for the optimal configuration of the points under some constraints. Arising from a concrete situation, concerning the ARGO-YBJ experiments, the goal is to find the optimal configuration of the detector, consisting of a single layer of resistive plate counters. Theoretical and computational results are presented for this location problem.