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Sufficient conditions for optimality of a (z,c−, c+)-sampling plan in multistage Bayesian acceptance sampling

Summary A (z, c^–, c⁺)-sampling plan is based on the following rule: Having observedy defectives in a cumulative sample of sizen, then, in case of yc^–(n)[yc⁺(n)] accept (reject) the lot; otherwise take a further sample of sizez(n, y). This type of sampling plan is shown to be optimal (within the set ofall sampling plans) with respect to the expected total cost in multistage Bayesian acceptance sampling and, thus, improves a single, double or multiple sampling plan in a natural way. Furthermore, some additional structure of an optimal (z, c^–, c⁺)-sampling is obtained; in particular c^±(n)c^±(n + 1) c^±(n)+1.

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Zusammenfassung Bei Anwendung eines (z, c^–, c⁺)-Stichprobenplanes ergibt sich folgende Entscheidungsvorschrift: Liegt eine Gesamtstichprobe vom Umfangn vor, diey schlechte Stücke enthält, so nehme man das Los im Falle yc^–(n) an, lehne es im Falle yc⁺(n) ab und ziehe ansonsten eine weitere Stichprobe vom Umfang z(n, y). Unter natürlichen Voraussetzungen wird gezeigt, daß ein solcher Stichprobenplan bzgl. der erwarteten Gesamtkosten in der Menge aller Bayesschen Stichprobenpläne optimal ist und somit einen einfachen, doppelten oder multiplen Prüfplan auf natürliche Weise verallgemeinert. Darüber hinaus wird gezeigt, daß die kritischen Funktionen c^±(n) eines optimalen (z, c^–, c⁺)-Planes die Eigenschaften c^±(n)c^±(n + 1)c^±(n) + 1 besitzen.

     

Swimming pool water--fractionation and genotoxicological characterization of organic constituents

Swimming pool water treatment in general includes flocculation, sand filtration, and subsequent disinfection with chlorine. The continuous chlorination and input of organic material by bathers in combination with recirculation of the pool water leads to an accumulation of disinfection by-products (DBPs) in the water. Several DBPs have been identified as human carcinogens and are thought to cause allergic asthma. Therefore, the elimination of DBPs is one major aim of pool water treatment. Using membrane filtration as an alternative treatment technology, DBPs can be removed more efficiently than with conventional treatment. In this study membrane filtration and genotoxicity testing were applied for the characterization of pool water constituents and for the identification of the necessary molecular weight cut off of the membrane for an efficient elimination. Two-step membrane filtration revealed that most of the DBPs (as adsorbable organically bound halogen, AOX) were present in the molecular weight fraction below 1000 g/mol. The fraction below 200 g/mol contained more than 30% of the AOX. The distribution of the dissolved organic carbon (DOC) across the fractions was similar to that of the AOX. The genotoxicity was found to be strongest in the low-molecular weight fraction. Thus, considerable DBP removal by membrane treatment requires membranes with low-molecular weight cut offs down to 200 g/mol. The comprehensive elimination of the genotoxic compounds requires further treatment steps.     

The disclosure of private data: measuring the privacy paradox in digital services

Privacy is a current topic in the context of digital services because such services demand mass volumes of consumer data. Although most consumers are aware of their personal privacy, they frequently do not behave rationally in terms of the risk-benefit trade-off. This phenomenon is known as the privacy paradox. It is a common limitation in research papers examining consumers’ privacy intentions. Using a design science approach, we develop a metric that determines the extent of consumers’ privacy paradox in digital services based on the theoretical construct of the privacy calculus. We demonstrate a practical application of the metric for mobile apps. With that, we contribute to validating respective research findings. Moreover, among others, consumers and companies can be prevented from unwanted consequences regarding data privacy issues and service market places can provide privacy-customized suggestions.     

The special status of actions in causal reasoning in rats.

A. P. Blaisdell, K. Sawa, K. J. Leising, and M. R. Waldmann (2006) reported evidence for causal reasoning in rats. After learning through Pavlovian observation that Event A (a light) was a common cause of Events X (an auditory stimulus) and F (food), rats predicted F in the test phase when they observed Event X as a cue but not when they generated X by a lever press. Whereas associative accounts predict associations between X and F regardless of whether X is observed or generated by an action, causal-model theory predicts that the intervention at test should lead to discounting of A, the regular cause of X. The authors report further tests of causal-model theory. One key prediction is that full discounting should be observed only when the alternative cause is viewed as deterministic and independent of other events, 2 hallmark features of actions but not necessarily of arbitrary events. Consequently, the authors observed discounting with only interventions but not other observable events (Experiments 1 and 2). Moreover, rats were capable of flexibly switching between observational and interventional predictions (Experiment 3). Finally, discounting occurred on the very first test trial (Meta-Analysis). These results confirm causal-model theory but refute associative accounts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enzymatic Protecting Group Techniques in bioorganic synthesis

The development and the application of enzyme-catalyzed transformations for the introduction and/or removal of protecting groups for hydroxyl-, amino-, mercapto- and carboxy functions is discussed. The various examples highlight the advantageous application of enzymes in comparison to classical chemical techniques in the chemistry of peptides, carbohydrates, alkaloids and steroids. Thus, the biocatalysts not only complement the arsenal of classical chemical methods, but offer viable and interesting alternatives to them.     

Bioorthogonal chemistry for site-specific labeling and surface immobilization of proteins

Understanding protein structure and function is essential for uncovering the secrets of biology, but it remains extremely challenging because of the high complexity of protein networks and their wiring. The daunting task of elucidating these interconnections requires the concerted application of methods emerging from different disciplines. Chemical biology integrates chemistry, biology, and pharmacology and has provided novel techniques and approaches to the investigation of biological processes. Among these, site-specific protein labeling with functional groups such as fluorophors, spin probes, and affinity tags has greatly facilitated both in vitro and in vivo studies of protein structure and function. Bioorthogonal chemical reactions, which enable chemo- and regioselective attachment of small-molecule probes to proteins, are particularly attractive and relevant for site-specific protein labeling. The introduction of powerful labeling techniques also has inspired the development of novel strategies for surface immobilization of proteins to create protein biochips for in vitro characterization of biochemical activities or interactions between proteins. Because this process requires the efficient immobilization of proteins on surfaces while maintaining structure and activity, tailored methods for protein immobilization based on bioorthogonal chemical reactions are in high demand. In this Account, we summarize recent developments and applications of site-specific protein labeling and surface immobilization of proteins, with a special focus on our contributions to these fields. We begin with the Staudinger ligation, which involves the formation of a stable amide bond after the reaction of a preinstalled azide with a triaryl phosphine reagent. We then examine the Diels-Alder reaction, which requires the protein of interest to be functionalized with a diene, enabling conjugation to a variety of dienophiles under physiological conditions. In the oxime ligation, an oxyamine is condensed with either an aldehyde or a ketone to form an oxime; we successfully pursued the inverse of the standard technique by attaching the oxyamine, rather than the aldehyde, to the protein. The click sulfonamide reaction, which involves the Cu(I)-catalyzed reaction of sulfonylazides with terminal alkynes, is then discussed. Finally, we consider in detail the photochemical thiol-ene reaction, in which a thiol adds to an ene group after free radical initiation. Each of these methods has been successfully developed as a bioorthogonal transformation for oriented protein immobilization on chips and for site-specific protein labeling under physiological conditions. Despite the tremendous progress in developing such transformations over the past decade, however, the demand for new bioorthogonal methods with improved kinetics and selectivities remains high.     

Characterization of progesterone profiles in fall-calving Norwegian Red cows

Progesterone profiles in Norwegian Red cows were categorized, and associations between the occurrence of irregularities in the profiles and the commencement of luteal activity were investigated. The cows were managed in 3 feeding trials from 1994 to 2001 and from 2005 to 2008 at the Norwegian University of Life Sciences. The cows were followed from calving, and the milk samples collected represented 502 lactations from 302 cows. Milk samples for progesterone analysis were taken 3 times weekly from 1994 throughout 1998 and from 2005 to 2008 and 2 times weekly from 1999 to 2001. Commencement of luteal activity was defined as the first day of 2 consecutive measurements of progesterone concentration ≥3 ng/mL not earlier than 10 d after calving. Delayed ovulation type I was defined as consistently low progesterone concentration, <3 ng/mL for ≥50 d postpartum. Delayed ovulation type II was defined as prolonged interluteal interval with milk progesterone measurements <3 ng/mL for ≥12 d between 2 luteal phases. Persistent corpus luteum (PCL) type I was defined as delayed luteolysis with milk progesterone ≥3 ng/mL for ≥19 d during the first estrous cycle postpartum. Persistent corpus luteum type II was defined as delayed luteolysis with milk progesterone ≥3 ng/mL for ≥19 d during subsequent estrous cycles before first artificial insemination. Delayed ovulation type I was present in 14.7%, delayed ovulation type II in 2.8%, PCL type I in 6.7%, and PCL type II in 3.3% of the profiles. Commencement of luteal activity was related to milk yield, parity, PCL type I, and the summated occurrence of PCL type I and II. The least squares means for the interval to commencement of luteal activity were 24.2 d when PCL type I and II were present and 29.5 d when PCL type I and II were absent. The likelihood of pregnancy to first service was not affected in cows with a history of PCL when artificial insemination was carried out at progesterone concentrations <3 ng/mL (i.e., during estrus); however, cows that had experienced PCL were more likely to be inseminated during a luteal phase. The occurrence of delayed ovulation and PCL in Norwegian Red cows was less than that reported in most other dairy populations.     

Die teilautomatisierte Verifizierung der getrennten Verarbeitung in der Cloud

Automatisiert mess- und auswertbarer Datenschutz in Cloud-Umgebungen kann potenziellen Cloud-Nutzern Datenschutzbedenken nehmen. Doch für jede Messung müssen vorab geeignete Datenquellen gefunden und sinnvoll kombiniert werden, um sich einer automatisierten Verifikation von Datenschutzzielen anzunähern. Dieser Beitrag schlägt ein solches Vorgehen für das Datenschutzziel der getrennten Verarbeitung vor.