Deletion of the C26 Methyl Substituent from the Bryostatin Analogue Merle 23 Has Negligible Impact on Its Biological Profile and Potency

Important strides are being made in understanding the effects of structural features of bryostatin 1, a candidate therapeutic agent for cancer and dementia, in conferring its potency toward protein kinase C and the unique spectrum of biological responses that it induces. A critical pharmacophoric element in bryostatin 1 is the secondary hydroxy group at the C26 position, with a corresponding primary hydroxy group playing an analogous role in binding of phorbol esters to protein kinase C. Herein, we describe the synthesis of a bryostatin homologue in which the C26 hydroxy group is primary, as it is in the phorbol esters, and show that its biological activity is almost indistinguishable from that of the corresponding compound with a secondary hydroxy group.     

An overview of protection of privacy in multibiometrics

Biometric authentication systems (BASs) have various advantages over traditional authentication systems such as password based systems. In BASs, information related to individuals’ physical and psychological characteristics is employed for authentication. The leakage of such information will breach individuals’ privacy severely. To simultaneously protect privacy and achieve higher authentication accuracy, privacy preserving multibiometric authentication systems (PPMASs) have been developed. This paper provides a comprehensive review of PPMASs. Specifically, we outline the requirements of PPMASs and discuss the state-of-the-art PPMASs. We also discuss PPMASs in the context of mobile and cloud based applications. Furthermore, we show the drawbacks of the existing PPMASs and point out the future research directions of PPMASs.     

Contract automata

Deontic logic as a way of formally reasoning about norms, an important area in AI and law, has traditionally concerned itself about formalising provisions of general statutes. Despite the long history of deontic logic, given the wide scope of the logic, it is difficult, if not impossible, to formalise all these notions in a single formalism, and there are still ongoing debates on appropriate semantics for deontic modalities in different contexts. In this paper, we restrict our attention to contracts between interactive parties, which are both general enough to be an interesting object of study but specific enough so as to narrow down the debates regarding the meaning of modalities, and present a formalism for reasoning about them.     

Measuring water utility performance using nonparametric linear programming

In this study, a cutting-edge methodology for measuring the performance of water utilities based on two-stage Data Envelopment Analysis (DEA) was applied to individual districts of a California-based water utility. A bootstrap technique involving the construction of confidence intervals was implemented to overcome the deterministic nature of conventional DEA, and a number of exogenous variables were incorporated into the model to help identify the factors affecting technical efficiency. Results indicated high overall performance achieved by the utility on average (92%). The number of connections and precipitation were found to be statistically significant exogenous variables, and both were determined to have a negative impact on efficiencies. The findings of this study are expected to be useful for guiding subsequent managerial improvement initiatives.     

Collaborative Network Topologies in Spatial Economies

Networks and Spatial Economics - Recently, it has been shown that networks with an arbitrary degree sequence may be a stable solution to a network formation game. Further, in recent years there has...     

NEW CHROMATOGRAPHIC METHODS FOR ASPHALT ANALYSIS

ABSTRACT

New methods in the analysis of asphalt by size exclusion chromatography (SEC) and supercritical fluid chromatography (SFC) are described. The evaporative analyser and viscometric detectors provide a more nearly universal response in SEC than does the UV detector; a number of alternatives to polystyrene as retention volume calibration standards were investigated. SFC permitted simulated distillation at much lower temperatures than in GC, with closer correspondence to actual distillation behaviour