Nonlinear dynamics of the interface of dielectric liquids in a strong electric field: Reduced equations of motion

The evolution of the interface between two ideal dielectric liquids in a strong vertical electric field is studied. It is found that a particular flow regime, for which the velocity potential and the electric field potential are linearly dependent functions, is possible if the ratio of the permittivities of liquids is inversely proportional to the ratio of their densities. The corresponding reduced equations for interface motion are derived. In the limit of small density ratio, these equations coincide with the well-known equations describing the Laplacian growth.Comment: 10 page

Parametric Forcing of Waves with Non-Monotonic Dispersion Relation: Domain Structures in Ferrofluids?

Surface waves on ferrofluids exposed to a dc-magnetic field exhibit a non-monotonic dispersion relation. The effect of a parametric driving on such waves is studied within suitable coupled Ginzburg-Landau equations. Due to the non-monotonicity the neutral curve for the excitation of standing waves can have up to three minima. The stability of the waves with respect to long-wave perturbations is determined $via$ a phase-diffusion equation. It shows that the band of stable wave numbers can split up into two or three sub-bands. The resulting competition between the wave numbers corresponding to the respective sub-bands leads quite naturally to patterns consisting of multiple domains of standing waves which differ in their wave number. The coarsening dynamics of such domain structures is addressed.Comment: 23 pages, 6 postscript figures, composed using RevTeX. Submitted to PR

The Good, the Bad and the Ugly: A Study of the Organization through the Lens of Popular Films of the Western World

This chapter examined portrayals of the morality of organizations using the lens of Western films. The work explored six decades of film, analyzing the organizational contexts and their agents, in order to understand filmmakers’ and audiences’ perceptions of organizational settings. In order to examine the organization as an entity within film, this chapter provided a content analysis of plot summaries from a purposefully selected body of top grossing box office films spanning 60 years. The plot summaries constituted a strong basis for identifying the characteristics of the organization as they are largely descriptive in nature and as such do not offer any evaluation or analysis of the film. Any assumptions about the character of organizations (or their members/employees) are unconscious, and as such they constitute a verbal description of what competent observers would say has occurred within the film. The plots were coded to reveal perceptions of positive, neutral, or negative organizational contexts and actions. This approach exposed the filmmakers symbolic placing of the organization in order to provide backdrops for the narrative. The plot analysis revealed that throughout the decades there has been a sophisticated portrayal in film of the role of the organization and the agents therein. A generally negative view of organizational contexts was demonstrated, with only religion and education shown as positive within the films selected. It was recognized that there would be value in extending this research to analyze a larger body of works. The selection criteria resulted in a wide but not comprehensive corpus of film genres. The body of works was sufficient to reveal the complexity of attitudes to organizational values and delivery which has evolved through time. Different selection criteria and more substantial narrative text could serve to confirm these results. Further implications for future research were discussed. While in the real-life sphere, there has been an emphasis on organizational standards and “corporate governance” delivering ethical exemplars, the film contexts highlight the complexities of delivering trusted organizations. The reality that there remains the potential for organizational corruption is well understood by the general public and clearly depicted within the film world. The conceptual contribution is original as limited work has been conducted on the organizational context in films. This work revealed the possibility of using this approach to further develop a greater understanding of perceptions of organizations

Electrodynamic Instability of a Self-Gravitating Fluid Cylinder under General Varying Electric Field

The electrodynamic instability of a self-gravitating dielectric fluid penetrated by a uniform axial electric field surrounded by a self-gravitating vacuum pervaded by general varying electric field is investigated. A general eigenvalue relation valid to all possible (symmetric and asymmetric) modes of perturbation for all (short and long) wavelengths is derived and discussed in detail. The model is gravitationally stable to the pure asymmetric disturbances modes while to symmetric modes it is so if the longitudinal wave number normalized with respect to the jet radius is equal to or greater than 1.0668 and vice versa. The axial electric fields pervaded interior and exterior to the cylinder are stabilizing or destabilizing for all disturbance modes according to some restrictions. The transverse varying electric field is purely stabilizing in the symmetric disturbances for all wavelengths, while it is stabilizing in the asymmetric disturbance under some restrictions. The electrodynamic force has a strong stabilizing influence in the symmetric mode and can suppress the gravitational instability above a certain value of the basic electric field

Study of the characteristics and outcomes of patients on mechanical ventilation in the intensive care unit of EL-Mahalla Chest Hospital

Background: Improving the outcome of mechanically ventilated patients remains a mission we all strive to achieve. Aim: To provide baseline information for epidemiological trends, prognostic factors, and outcomes of patients on MV that will help planning of proper MV management programs. Patients and methods: All adult patients received MV at EL-Mahalla Chest Hospital ICU between July 2013 and June 2014 were prospectively recruited. Different demographic, clinical and laboratory variables were recorded at the time of admission, during the ICU stay and at time of discharge. Results: Out of the 412 patients admitted to the ICU, 130 patients received MV, either invasive MV (40%), noninvasive MV (50.7%) and 9.2% of the patients showed noninvasive failure and needed invasive ventilation. The commonest indication of MV was acute on top of chronic respiratory failure (77.7%). Chronic obstructive pulmonary disease was the most prevalent diagnosis (48.5%). Invasive MV was associated with low Glasgow coma scale, high APACHE II score, low admission PH, Po2 and high Pco2 higher morbidity and mortality rates compared to noninvasive MV. For an optimal discrimination of patients with highest risk of ICU mortality, a cutoff point of APACHE II score >30 showed sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 57.1, 88.1, 48, 91.4 and 0.73 respectively. At a cutoff point of GCC >30, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 71.4, 76.1, 36.6, 93.3 and 0.689 respectively. Conclusion: Survival among mechanically ventilated patients depended on the baseline characteristics at the start of MV, as well as on the development of complications and the management protocols in the ICU

Zinc alpha 2 glycoprotein as an early biomarker of diabetic nephropathy in patients with type 2 diabetes mellitus

Abstract Introduction: Although microalbuminuria remains the gold standard for early detection of diabetic nephropathy (DN), it is not a sufficiently accurate predictor of DN risk. Thus, new biomarkers that would help to predict DN risk earlier and possibly prevent the occurrence of end-stage kidney disease are being investigated. Objective: To investigate the role of zinc-alpha-2-glycoprotein (ZAG) as an early marker of DN in type 2 diabetic (T2DM) patients. Methods: 88 persons were included and classified into 4 groups: Control group (group I), composed of normal healthy volunteers, and three patient groups with type 2 diabetes mellitus divided into: normo-albuminuria group (group II), subdivided into normal eGFR subgroup and increased eGFR subgroup > 120 mL/min/1.73m2), microalbuminuria group (group III), and macroalbuminuria group (group IV). All subjects were submitted to urine analysis, blood glucose levels, HbA1c, liver function tests, serum creatinine, uric acid, lipid profile and calculation of eGFR, urinary albumin creatinine ratio (UACR), and measurement of urinary and serum ZAG. Results: The levels of serum and urine ZAG were higher in patients with T2DM compared to control subjects and a statistically significant difference among studied groups regarding serum and urinary ZAG was found. Urine ZAG levels were positively correlated with UACR. Both ZAG levels were negatively correlated with eGFR. Urine ZAG levels in the eGFR ˃ 120 mL/min/1.73m2 subgroup were higher than that in the normal eGFR subgroup. Conclusion: These findings suggest that urine and serum ZAG might be useful as early biomarkers for detection of DN in T2DM patients, detectable earlier than microalbuminuria

Modeling and characterization of beryllium reflector elements under irradiation conditions

This study aims at modeling the beryllium reflector poisoning under neutron irradiation conditions and calculating the impact of beryllium poisoning on the core parameters of ETRR-2 research reactor. The CITVAP code was used to calculate the neutron flux and parameters of ETRR-2 core with beryllium reflector elements. The neutron flux in each reflector element was calculated to solve the modeling equations for the atomic densities of lithium-6 (6Li), tritium-3 (3H), and helium-3 (3He) using the BERYL program. The results are discussed based on CITVAP calculations of the core excess reactivity and cycle length Full Power Days (FPD). Possible solutions to minimize the degradation due to beryllium poisoning are also discussed and compared based on calculations