A Numerical Investigation of Unsteady Bubbly Cavitating Nozzle Flows

The effects of unsteady bubble dynamics on cavitating flow through a converging-diverging nozzle are investigated numerically. A continuum model that couples the Rayleigh-Plesset equation with the continuity and momentum equations is used to formulate unsteady, quasi-one-dimensional partial differential equations. These equations are solved numerically using a Lagrangian finite volume method. Special formulations are used at the boundary cells to allow Eulerian boundary conditions to be specified. Flow regimes studied include those where steady state solutions exist, and those where steady state solutions diverge at the so-called flashing instability. These latter flows consist of unsteady bubbly shock waves travelling downstream in the diverging section of the nozzle. The computations show reasonable agreement with an experiment that measures the spatial variation of pressure, velocity and void fraction for steady shockfree flows, and good agreement with an experiment that measures the shock position and throat pressure for flows with bubbly shocks

Total energy expenditure in obese Kuwaiti primary school children assessed by the doubly-labelled water technique

The aim of this pilot study was to assess body composition and total energy expenditure (TEE) in 35 obese 7–9 years old Kuwaiti children (18 girls and 17 boys). Total body water (TBW) and TEE were assessed by doubly-labeled water technique. TBW was derived from the intercept of the elimination rate of deuterium and TEE from the difference in elimination rates of 18O and deuterium. TBW was used to estimate fat-free mass (FFM), using hydration factors for different ages and gender. Fat mass (FM) was calculated as the difference between body weight and FFM. Body weight was not statistically different but TBW was significantly higher (p = 0.018) in boys (44.9% ± 3.3%) than girls (42.4% ± 3.0%), while girls had significantly higher estimated FM (45.2 ± 3.9 weight % versus 41.6% ± 4.3%; p = 0.014). TEE was significantly higher in boys (2395 ± 349 kcal/day) compared with girls (1978 ± 169 kcal/day); p = 0.001. Estimated physical activity level (PAL) was significantly higher in boys; 1.61 ± 0.167 versus 1.51 ± 0.870; p = 0.034. Our results provide the first dataset of TEE in 7–9 years old obese Kuwaiti children and highlight important gender differences to be considered during the development of school based interventions targeted to combat childhood obesity

Securing address registration in location/ID split protocol using ID-based cryptography

The Locator/ID Separation Protocol (LISP) is a routing architecture that provides new semantics for IP addressing. In order to simplify routing operations and improve scalability in future Internet, the LISP separates the device identity from its location using two different numbering spaces. The LISP also, introduces a mapping system to match the two spaces. In the initial stage, each LISP-capable router needs to register with a Map Server, this is known as the Registration stage. However, this stage is vulnerable to masquerading and content poisoning attacks. Therefore, a new security method for protecting the LISP Registration stage is presented in this paper. The proposed method uses the ID-Based Cryptography (IBC) which allows the mapping system to authenticate the source of the data. The proposal has been verified using formal methods approach based on the well-developed Casper/FDR tool

Essentially Normal Composition Operators on the Hardy Space

In this presentation, we will explore composition operators on the Hardy space. We will investigate what it means for such composition operators to be essentially normal. The following question will be answered in this presentation: Are there any composition operators on the Hardy space which are essentially normal but which are not compact

SUSTAINABILITY IN INFORMATION SYSTEMS AUDITING

Auditing is a systematic process of obtaining and evaluating evidence of activities, events or transactions. Currently, audit practices have been revolutionized by the development of information technology and basically information systems auditing focuses on assessing proper implementation, operation and control of information systems resources within organisation. Several frameworks have been formulated for information systems auditing implementation to achieve improvement in auditing performance related to compliance requirements, internal controls evaluation and information systems success. However, sustainability dimensions in the information systems auditing practices and the development of appropriate framework are not enough discussed in the literature although sustainability is becoming significant in achieving certain organisation‘s objective. Therefore, this study intends to analyse the relevant requirements by auditors and sustainability factors and use them to formulate IS audit by integrating sustainability in the auditing process. Thus, improve audit performance and enhanced accountability and integrity of auditors

(2,9-Dimethyl-1,10-phenanthroline-κ2 N,N′)diiodidocadmium

In the title compound, [CdI2(C14H12N2)], the mol­ecule sits on a crystallographic twofold axis. The coordination sphere of the CdII atom is built of two symmetry-equivalent N atoms of one 2,9-dimethyl-1,10-phenanthroline (dmphen) ligand and two symmetry-equivalent I atoms, thus forming a distorted tetra­hedral geometry. Inversion-related mol­ecules inter­act along the c-axis direction by π–π stacking inter­actions between the phenanthroline ring systems, with centroid–centroid distances of 3.707 (9) and 3.597 (10) Å

Centralization of cleft care in the UK. Part 6:a tale of two studies

OBJECTIVES: We summarize and critique the methodology and outcomes from a substantial study which has investigated the impact of reconfigured cleft care in the United Kingdom (UK) 15 years after the UK government started to implement the centralization of cleft care in response to an earlier survey in 1998, the Clinical Standards Advisory Group (CSAG). SETTING AND SAMPLE POPULATION: A UK multicentre cross-sectional study of 5-year-olds born with non-syndromic unilateral cleft lip and palate. Data were collected from children born in the UK with a unilateral cleft lip and palate between 1 April 2005 and 31 March 2007. MATERIALS AND METHODS: We discuss and contextualize the outcomes from speech recordings, hearing, photographs, models, oral health and psychosocial factors in the current study. We refer to the earlier survey and other relevant studies. RESULTS: We present arguments for centralization of cleft care in healthcare systems, and we evidence this with improvements seen over a period of 15 years in the UK. We also make recommendations on how future audit and research may configure. CONCLUSIONS: Outcomes for children with a unilateral cleft lip and palate have improved after the introduction of a centralized multidisciplinary service, and other countries may benefit from this model. Predictors of early outcomes are still needed, and repeated cross-sectional studies, larger longitudinal studies and adequately powered trials are required to create a research-led evidence-based (centralized) service

Permeability of phospholipid membrane for small polar molecules determined from osmotic swelling of giant phospholipid vesicles

A method for determining permeability of phospholipid bilayer based on the osmotic swelling of micrometer-sized giant unilamellar vesicles (GUVs) is presented as an alternative to the two established techniques, dynamic light scattering on liposome suspension, and electrical measurements on planar lipid bilayers. In the described technique, an individual GUV is transferred using a micropipette from a sucrose/glucose solution into an isomolar solution containing the solute under investigation. Throughout the experiment, vesicle cross-section is monitored and recorded using a digital camera mounted on a phase-contrast microscope. Using a least-squares procedure for circle fitting, vesicle radius R is computed from the recorded images of vesicle cross-section. Two methods for determining membrane permeability from the obtained R(t) dependence are described: the first one uses the slope of R(t) for a spherical GUV, and the second one the R(t) dependence around the transition point at which a flaccid vesicle transforms into a spherical one. We demonstrate that both methods give consistent estimates for membrane permeability.Comment: 40 pages, 8 figures, to appear in Advances in Planar Lipid Membranes and Liposomes vol. 1