In Vitro Antioxidant Activity of root extracts of Heliotropium eichwaldi Stued. ex DC

ABSTRACT In vitro antioxidant activity of methanolic and aqueous root extracts of Heliotropium eichwaldi Stued. ex DC. was determined by DPPH free radical scavenging assay and hydrogen peroxide scavenging activity. The extract revealed marked activity as a radical scavenger in a study indicating that extracts have ability to donate hydrogen. The absorption is stoichiometric in respect to the number of electrons taken up. Concentration of 0.1 mg/ml of methanolic extract (HME) and aqueous root extract (HAE) of Heliotropium eichwaldi exhibited 62.73% and 57.18% DPPH scavenging activity. The antioxidant activity of these extracts towards hydrogen peroxide was also reported. A 76.94% and 70.79% of inhibition of hydrogen peroxide was observed with HME and HAE respectively, when compared with control, at a concentration of 0.1 mg/ml using ascorbic acid as standard and positive control on analysis with UV-Visible Spectrophotometer. The results conclude that the extracts are a potential source of antioxidants of natural origin and may be a candidate for treating pathologies related to free radical oxidation due to its overall antioxidant effect in scavenging free radicals and active oxygen species

Recovering Shared Objects Without Stable Storage

This paper considers the problem of building fault-tolerant shared objects when processes can crash and recover but lose their persistent state on recovery. This Diskless Crash-Recovery (DCR) model matches the way many long-lived systems are built. We show that it presents new challenges, as operations that are recorded at a quorum may not persist after some of the processes in that quorum crash and then recover. To address this problem, we introduce the notion of crash-consistent quorums, where no recoveries happen during the quorum responses. We show that relying on crash-consistent quorums enables a recovery procedure that can recover all operations that successfully finished. Crash-consistent quorums can be easily identified using a mechanism we term the crash vector, which tracks the causal relationship between crashes, recoveries, and other operations. We apply crash-consistent quorums and crash vectors to build two storage primitives. We give a new algorithm for multi-writer, multi-reader atomic registers in the DCR model that guarantees safety under all conditions and termination under a natural condition. It improves on the best prior protocol for this problem by requiring fewer rounds, fewer nodes to participate in the quorum, and a less restrictive liveness condition. We also present a more efficient single-writer, single-reader atomic set - a virtual stable storage abstraction. It can be used to lift any existing algorithm from the traditional Crash-Recovery model to the DCR model. We examine a specific application, state machine replication, and show that existing diskless protocols can violate their correctness guarantees, while ours offers a general and correct solution

Evidence-based Kernels: Fundamental Units of Behavioral Influence

This paper describes evidence-based kernels, fundamental units of behavioral influence that appear to underlie effective prevention and treatment for children, adults, and families. A kernel is a behavior–influence procedure shown through experimental analysis to affect a specific behavior and that is indivisible in the sense that removing any of its components would render it inert. Existing evidence shows that a variety of kernels can influence behavior in context, and some evidence suggests that frequent use or sufficient use of some kernels may produce longer lasting behavioral shifts. The analysis of kernels could contribute to an empirically based theory of behavioral influence, augment existing prevention or treatment efforts, facilitate the dissemination of effective prevention and treatment practices, clarify the active ingredients in existing interventions, and contribute to efficiently developing interventions that are more effective. Kernels involve one or more of the following mechanisms of behavior influence: reinforcement, altering antecedents, changing verbal relational responding, or changing physiological states directly. The paper describes 52 of these kernels, and details practical, theoretical, and research implications, including calling for a national database of kernels that influence human behavior

Chemistry and in vivo profile of ent-kaurene glycosides of Stevia rebaudiana Bertoni—An overview

181-189The ent-kaurene type of diterpenoid glycosides are typically the characteristics of leaves of Stevia rebaudiana Bertoni, the plant with sweet leaves. Relative to sucrose, the potent sweetness intensities of these glycosides have projected them as cost effective sucrose substitute. In the present paper, the structural and physicochemical features of ent-kaurene glycosides of Stevia along with an insight into the structure-sweetness relationship are presented. Despite their age-old widespread use in several parts of the world, there still remains certain concern regarding safety profile of these glycosides. Henceforth, the pharmacokinetic, pharmacological and toxicological evaluation of ent-kaurene glycosides is reviewed

Building Consistent Transactions with Inconsistent Replication (Extended Version)

Abstract Application programmers increasingly prefer distributed storage systems with strong consistency and distributed transactions (e.g., Google's Spanner) for their strong guarantees and ease of use. Unfortunately, existing transactional storage systems are expensive to use -in part because they require costly replication protocols, like Paxos, for fault tolerance. In this paper, we present a new approach that makes transactional storage systems more affordable: we eliminate consistency from the replication protocol while still providing distributed transactions with strong consistency to applications. We present TAPIR -the Transactional Application Protocol for Inconsistent Replication -the first transaction protocol to use a novel replication protocol, called inconsistent replication, that provides fault tolerance without consistency. By enforcing strong consistency only in the transaction protocol, TAPIR can commit transactions in a single round-trip and order distributed transactions without centralized coordination. We demonstrate the use of TAPIR in a transactional key-value store, TAPIR-KV. Compared to conventional systems, TAPIR-KV provides better latency and throughput

Building Consistent Transactions with Inconsistent Replication

Abstract Application programmers increasingly prefer distributed storage systems with strong consistency and distributed transactions (e.g., Google's Spanner) for their strong guarantees and ease of use. Unfortunately, existing transactional storage systems are expensive to use -in part because they require costly replication protocols, like Paxos, for fault tolerance. In this paper, we present a new approach that makes transactional storage systems more affordable: we eliminate consistency from the replication protocol while still providing distributed transactions with strong consistency to applications. We present TAPIR -the Transactional Application Protocol for Inconsistent Replication -the first transaction protocol to use a novel replication protocol, called inconsistent replication, that provides fault tolerance without consistency. By enforcing strong consistency only in the transaction protocol, TAPIR can commit transactions in a single round-trip and order distributed transactions without centralized coordination. We demonstrate the use of TAPIR in a transactional key-value store, TAPIR-KV. Compared to conventional systems, TAPIR-KV provides better latency and throughput

Azaindoles: Noncovalent DprE1 Inhibitors from Scaffold Morphing Efforts, Kill Mycobacterium tuberculosis and Are Efficacious <i>in Vivo</i>

We report 1,4-azaindoles as a new inhibitor class that kills Mycobacterium tuberculosis <i>in vitro</i> and demonstrates efficacy in mouse tuberculosis models. The series emerged from scaffold morphing efforts and was demonstrated to noncovalently inhibit decaprenylphosphoryl-β-d-ribose2′-epimerase (DprE1). With “drug-like” properties and no expectation of pre-existing resistance in the clinic, this chemical class has the potential to be developed as a therapy for drug-sensitive and drug-resistant tuberculosis