Turbulent convective heat transfer and pressure drop of dilute CuO (copper oxide) - water nanofluid Inside a circular tube

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.Turbulent forced convective heat transfer and pressure drop of 0.01 vol.% CuO-water nanofluid was assessed experimentally. The nanofluids were made flow into a heated horizontal tube under uniform constant heat flux within Reynolds number range of 11,500 to 32,000. The first objective is to know how close traditional correlation/formula for, both, heat transfer and pressure drop can predict nanofluid’s heat transfer and pressure drop. The second is to know how nanofluid’s convective heat transfer and pressure drop are compared to those of its base fluid; in this case water. The results showed that the abovementioned characteristics of the nanofluid can be predicted by the traditional correlation available. It is also found that the nanofluid’s Nusselt number and friction factor, which represent the heat transfer rate and pressure drop, respectively, are close to those of water. Hence, there is no anomaly due to the dispersed nanoparticles within the water.KACST (King Abdulaziz City for Science and Technology

Isolation of verotoxin-producing Escherichia coli associated with diarrhoea in Malaysia containing plasmids showing homology with biotinylated Shiga-like toxin DNA gene probes

Three strains of verotoxin-producing Escherichia coli isolated from patients with haemorrhagic colitis harboured plasmids ranging in size from 2.7 kb to 91.2 kb. Those plasmids ranging from 2.7 kb to 6.8 kb hybridized to Shiga-like toxin I and Shiga-like toxin II gene probes

Exploiting the Synergy Between Gossiping and Structured Overlays

In this position paper we argue for exploiting the synergy between gossip-based algorithms and structured overlay networks (SON). These two strands of research have both aimed at building fault-tolerant, dynamic, self-managing, and large-scale distributed systems. Despite the common goals, the two areas have, however, been relatively isolated. We focus on three problem domains where there is an untapped potential of using gossiping combined with SONs. We argue for applying gossip-based membership for ring-based SONs---such as Chord and Bamboo---to make them handle partition mergers and loopy networks. We argue that small world SONs---such as Accordion and Mercury---are specifically well-suited for gossip-based membership management. The benefits would be better graph-theoretic properties. Finally, we argue that gossip-based algorithms could use the overlay constructed by SONs. For example, many unreliable broadcast algorithms for SONs could be augmented with anti-entropy protocols. Similarly, gossip-based aggregation could be used in SONs for network size estimation and load-balancing purposes

p-Adic Models of Ultrametric Diffusion Constrained by Hierarchical Energy Landscapes

We demonstrate that p-adic analysis is a natural basis for the construction of a wide variety of the ultrametric diffusion models constrained by hierarchical energy landscapes. A general analytical description in terms of p-adic analysis is given for a class of models. Two exactly solvable examples, i.e. the ultrametric diffusion constraned by the linear energy landscape and the ultrametric diffusion with reaction sink, are considered. We show that such models can be applied to both the relaxation in complex systems and the rate processes coupled to rearrangenment of the complex surrounding.Comment: 14 pages, 6 eps figures, LaTeX 2.0

Differential Redox Regulation of ORAI Ion Channels: A Mechanism to Tune Cellular Calcium Signaling

Reactive oxygen species (ROS) are involved in many physiological and pathophysiological cellular processes. We used lymphocytes, which are exposed to highly oxidizing environments during inflammation, to study the influence of ROS on cellular function. Calcium ion (Ca2+) influx through Ca2+ release–activated Ca2+ (CRAC) channels composed of proteins of the ORAI family is essential for the activation, proliferation, and differentiation of T lymphocytes, but whether and how ROS affect ORAI channel function have been unclear. Here, we combined Ca2+ imaging, patch-clamp recordings and measurements of cell proliferation and cytokine secretion to determine the effects of hydrogen peroxide (H2O2) on ORAI channel activity and human T helper lymphocyte (TH cell) function. ORAI1, but not ORAI3, channels were inhibited by oxidation by H2O2. The differential redox sensitivity of ORAI1 and ORAI3 channels depended mainly on an extracellularly located reactive cysteine, which is absent in ORAI3. TH cells became progressively less redox-sensitive after differentiation into effector cells, a shift that would allow them to proliferate, differentiate, and secrete cytokines in oxidizing environments. The decreased redox sensitivity of effector TH cells correlated with increased expression of Orai3 and increased abundance of several cytosolic antioxidants. Knockdown of ORAI3 with small-interfering RNA rendered effector TH cells more redox-sensitive. The differential expression of Orai isoforms between naïve and effector TH cells may tune cellular responses under oxidative stress

Why do consumers trust online travel websites? Drivers and outcomes of consumer trust toward online travel websites

Egypt is currently one of the leading nations especially in the Middle East region with a well-established e-commerce environment and advanced IT infrastructure, but rapid growth of e-commerce will soon occur in other nations with similar consumption patterns. This study tests a model of antecedents (consumer experience, propensity to trust, reputation, perceived website size, ease of use, perceived usefulness, and website quality) and consequences of consumers’ trust toward online travel websites. Trust is expected to predict consumer attitude, perceived risk, and intention to purchase travel online. Data of 1,431 users of online travel websites were selected from the Supreme Council of Universities Database–Egypt (SCU) and analyzed through structural equation modeling. The findings show that all the aforementioned factors with the exception of consumer experience influence consumer trust toward online travel websites. Trust influences consumers’ attitude, perceived risk, and intention to purchase travel online

EFFECT OF RASAPRAVICHARANA CIKITSA (TASTE SPECIFIC DRUG THERAPY) IN KAPHA DOMINANCE OF TAMAKA SWASA (ASTHMA) - A CASE SERIES

Rasapravicharana cikitsa is the administration of drugs in accordance with the Rasam (taste) after assessing the Doshic imbalance in diseases. The basic approach of Ayurveda is to normalize the Doshas in aggravated or depleted conditions occurred in the manifestation of disease. The objective of the study was to assess the effect of Rasapravicharana cikitsa (taste specific drug therapy) in aggravated Kapha dosha of Kapha dominant Tamaka swasa (asthma). The study was conducted on 10 patients between the age group 16 to 70 yrs of both the sexes. The patients were administered with Katu (pungent) rasa drug ie, powder of the dried fruit of Maricham (Piper nigrum Linn) at the dose of 500 mg, Tikta (bitter) rasa drug i.e., dried Vasa leaf powder (Adhatoda vasica Nees) at the dose of 3gm, and Kashaya (astringent) rasa drug i.e., powder of the dried fruit pericarp of Haritaki (Terminalia chebula (Gaertn.) Retz.) at the dose of 3gm, 8 AM and 8 PM after food daily in luke warm water respectively for a period of two weeks each. The Katu rasa drug administered for 14 days produced highly significant reduction in dyspnoea, cough bout frequency, wheeze, expectoration of sputum and quantity of sputum, and significant improvement in PEFRate. But no significant improvement was observed in PEF%. The administration of Tikta rasa drug in the next 14 days resulted in highly significant reduction in cough bout frequency and expectoration of sputum and significant reduction in dyspnoea. The reduction was maintained in other signs and symptoms. The Kashaya rasa drug used in the last 14 days significantly improved PEFRate. Reduction in other signs and symptoms was maintained. The management according to Rasapravicharana cikitsa has a significant role in the pacification of Doshas involved in the manifestation of diseases. &nbsp

THE ROLE OF AIRWAY MUCUS HYPER SECRETION DUE TO KAPHA VITIATION IN TAMAKA SVASA (ASTHMA): PATHOPHYSIOLOGY AND PHARMACOTHERAPEUTIC APPROACH

Tamakasvasa (asthma) is a mucous hypersecretory respiratory disease. The inspissated mucus produced by vitiated Kapha obstructs the bronchi and other small air passages in the pathological development of the disease. Physiologically Kapha dosa provides strength (Bala) to the body due to the intrinsic qualities unctuousness (Snigda), coldness (Sita), heaviness (Guru), slowness (Manda), smoothness (Slasna), softness (Mrisna), stability (Sthira) etc. Being an organ in the specific site of Kapha dosha i.e., thorax (Uras), production of mucus in lungs is normal. Etiological factors that irritate respiratory tract stimulate inflammatory process and due to this, mucus is produced in excess. Due to the excessive vitiation of qualities of Kapha the mucus turns highly viscous and the normal clearance of mucus by airflow and ciliary function is hampered. Thus gelatinous mucus plugs tend to develop in the airways. The gel-forming MUC genes MUC2, MUC5AC and MUC5B commonly seen in respiratory secretions and stomach, duodenum, gall bladder etc have major role in the formation of airway mucus. Due to the ingestion of unwholesome food stomach (Amasaya) where Kapha reside, act as the organ of origin of the disease. The main pharmacotherapeutic objective in the management of Tamakasvasa is reduction of airway obstruction and airflow limitation by enhancing mucus clearance. This can be achieved by altering the rheological properties of bronchial mucus and inhibition of mucus hyper secretion and airway hyper responsiveness by procedure based therapies and pharmacological methods of Sleshmavilayana, Srotomardavakarana and rationale use of taste specific drug therapy (Rasapravicarana chikitsa)