Inhibitory activity of ginger rhizome on airway and uterine smooth muscle preparations

In this study, we describe the tracheal-relaxant and tocolytic activities of the methanol (ME) and aqueous (AQ) crude extracts of ginger (rhizome of Zingiber officinale) in an attempt to rationalize its traditional use in disorders of airways and uterine hyperactivity. Both of the ginger extracts dose-dependently relaxed K⁺ (80 mM) and carbachol (CCh, 1 μM)-induced contractions with more potency against K⁺, similar to that elicited by verapamil, a Ca²⁺ channel blocker. In isolated uterine preparations, the extracts suppressed the K⁺-induced contractions with respective EC₅₀ values of 0.03 mg/ml (0.02–0.05, 95% CI) and 0.05 mg/ml (0.04–0.06). Activity-directed fractionation of AQ yielded an organic and an aqueous fraction with the activities concentrated in the former. Both the crude extracts were found safe in mice up to the oral dose of 5 g/kg when tested for acute toxicity for 24 h. The study shows that ginger possesses tracheal and uterine smooth muscle relaxant activity, possibility mediated via Ca²⁺ channel blockade, justifying its use in disorders such as asthma, cough as well as in dysmenorrhoea and uterine and menstrual spasms and congestion.     

Bias dependence of high-frequency noise in heterojunction bipolar transistors

Hawkins' isothermal model developed to study noise in bipolar junction transistors (BJTs) is modified to investigate bias-dependent noise in heterojunction bipolar transistors (HBTs) by incorporating thermal effects. It is shown that the inclusion of thermal effects into the high-frequency noise model of HBTs is necessary as the temperature of the device may become very different from the ambient temperature, especially at high bias current. Calculation of the noise figure by including the thermal effect shows that the isothermal calculation may underestimate the noise figure at high bias current. It is observed that noise at low bias is ideality factor n dependent whereas high bias noise is insensitive to the variation of n. Moreover, the common base current gain plays a major role in the calculation of the minimum noise figure. The excellent fit obtained between the theoretical calculation and the measured data are attributed to the inclusion of the bias-dependent junction heating as well as C/sub De/ and C/sub bc/ into the present calculation.     

An asymmetric line-axis compound parabolic concentrating single basin solar still

An asymmetric line-axis compound parabolic concentrating single basin solar still of concentration 1.15, exit aperture 0.24 metres and length 0.48 metres, 30° inclination and 60° half acceptance angle has been designed fabricated and tested.     

Chemical composition and nutritional quality of tehineh (sesame butter)

The chemical composition and nutritional quality of tehineh, a paste of dehulled roasted sesame seeds, from Saudi Arabia and other countries, were studied. Results showed 24.7% protein, 58.9% fat, 2.3% fiber, 3.0% ash and <1.0% moisture. The tehineh contained relatively high amounts (mg/100 g) of P (692), Mg (362), Fe (7.19), Cu (1.96), Mn (1.46) and Zn (7.82) and low amounts of Ca (61) and Se (0.05). Gas-liquid chromatography (GLC) analysis of the oil revealed percentages of 42.4 for oleic, 39.7 for linoleic, 9.8 for palmitic and 6.4 for stearic acid. Lysine was the only limiting amino acid with a chemical score of 64, while the sulphur-containing amino acids (methionine + cystine) and tryptophan were present in amounts exceeding the requirement of the FAO/WHO (1973) reference protein. The in vitro protein digestibility (IVPD) value of 83.3% and the calculated protein efficiency ratio (C-PER), 2.14, were slightly higher than those of sesame seeds and both values were lower than the IVPD and C-PER of 90.0% and 2.50, respectively, for ANRC casein.     

Design and control of an olefin metathesis reactive distillation column

This paper considers the design and control of a reactive distillation column in which one reactant is consumed and two products are formed (A?B+C). The volatilities are α_B>α_A>α_C, i.e. the reactant is intermediate boiling between the two products. The metathesis of 2-pentene is considered as the demonstrative example. The column has a single feed of the intermediate boiling reactant. The distillate contains mostly light component and the bottoms mostly heavy.Three designs are considered: the base case (low-conversion/low-pressure), a low-conversion/high-pressure case and a high-conversion/high-pressure case. The base design is obtained from the literature, and the other two steady-state designs are optimized with respect to the total annual cost. All the designs are found to be openloop stable. Five control structures are studied for the base design. Then the best two structures are applied to the remaining two designs. This category of reactive distillation exhibits less challenging problems than other categories since it uses a single feed, which eliminates the need for the control structure to perfectly balance two fresh feeds.Simulation results demonstrate that effective dynamic control is provided by a control structure that uses two temperatures to maintain the purities of both product streams. No internal composition measurement is required. This structure is found to be robust and stable and rejects loads and tracks setpoints very well.     

Using Automated Negotiation for Grid Services

The popularity of grid services has widened their application to numerous domains and increased the utilization of computational resources. In order to create more incentives for the resources owners to lease their resources and prevent users from wasting the resources, the introduction of a market-oriented grid is inevitable. However, the issues for the negotiation between service provider and consumer over the supply and demand of resources can be complex, with highly interdependent issues. In this research, a simulated automated negotiation mechanism including a co-evolutionary mechanism and a modified game theory approach is proposed, to assist them in reaching an agreement over the conflicting issues. In the proposed architecture, the co-evolution process is able to reduce the multiple dimensional search space into a two-dimension search space and identify the appropriate negotiation strategies for the negotiating agents to form a payoff matrix which can be used for the game theory related stage of their interaction. The multiple stage negotiation process is introduced to improve the negotiation result. In this paper, an application which requires a large amount of computational resources to process the data generated from mobile devises is used to demonstrate that the proposed system is able to resolve the conflicts and obtain a valid solution.     

A comparison between reliability analyses based primarily on disjointness or statistical independence: The case of the generalized indra network

A switching expression is readily convertible to a reliability expression if (a) all ORed terms are disjoint, and (b) all ANDed sums are statistically independent. The usual approach of system reliability analysis makes a primary use of (a) and a secondary use of (b). An alternative approach reverses the roles of (a) and (b). Symbolic reliability expressions for the source-to-terminal reliability of a generalized Indra network (GIN) with nonidentical components are derived by the two approaches. For this particular case, the second approach leads to a shorter, more elegant derivation and simpler novel results. Typical plots of the GIN reliability functions are presented and their properties are discussed.     

Harmonic and intermodulation performance in an R-LED series network

Analytical expressions are obtained for predicting the harmonic and intermodulation performance of R-LED series networks. These expressions are in terms of the ordinary Bessel functions with arguments depenedent on the modulation index.     

The Bivariate Transmuted Family of Distributions: Theory and Applications

The bivariate distributions are useful in simultaneous modeling of two random variables. These distributions provide a way to model models. The bivariate families of distributions are not much widely explored and in this article a new family of bivariate distributions is proposed. The new family will extend the univariate transmuted family of distributions and will be helpful in modeling complex joint phenomenon. Statistical properties of the new family of distributions are explored which include marginal and conditional distributions, conditional moments, product and ratio moments, bivariate reliability and bivariate hazard rate functions. The maximum likelihood estimation (MLE) for parameters of the family is also carried out. The proposed bivariate family of distributions is studied for the Weibull baseline distributions giving rise to bivariate transmuted Weibull (BTW) distribution. The new bivariate transmuted Weibull distribution is explored in detail. Statistical properties of the new BTW distribution are studied which include the marginal and conditional distributions, product, ratio and conditional momenst. The hazard rate function of the BTW distribution is obtained. Parameter estimation of the BTW distribution is also done. Finally, real data application of the BTW distribution is given. It is observed that the proposed BTW distribution is a suitable fit for the data used.     

A review on fault detection and diagnosis techniques: basics and beyond

Safety and reliability are absolutely important for modern sophisticated systems and technologies. Therefore, malfunction monitoring capabilities are instilled in the system for detection of the incipient faults and anticipation of their impact on the future behavior of the system using fault diagnosis techniques. In particular, state-of-the-art applications rely on the quick and efficient treatment of malfunctions within the equipment/system, resulting in increased production and reduced downtimes. This paper presents developments within Fault Detection and Diagnosis (FDD) methods and reviews of research work in this area. The review presents both traditional model-based and relatively new signal processing-based FDD approaches, with a special consideration paid to artificial intelligence-based FDD methods. Typical steps involved in the design and development of automatic FDD system, including system knowledge representation, data-acquisition and signal processing, fault classification, and maintenance related decision actions, are systematically presented to outline the present status of FDD. Future research trends, challenges and prospective solutions are also highlighted.