Supporting Mobile Distributed Services

With sensors becoming increasingly ubiquitous, there is a tremendous potential for services which can take advantage of the data collected by these sensors, from the important -- such as detecting medical emergencies and imminent natural disasters -- to the mundane -- such as waiting times experienced by diners at restaurants. This information can then be used to offer useful services. For example, a busy professional could find a restaurant to go to for a quick lunch based on information available from smartphones of people already there having lunch, waiting to be seated, or even heading there; a government could conduct a census in real-time, or “sense” public opinion. I refer to such services as mobile distributed services. The barriers to offering mobile distributed services continue to be prohibitive for most: not only must these services be implemented, but they would also inevitably compete for resources on people's devices. This is in part because such services are poorly understood, and consequently, there is limited language support for programming them. In this thesis, I address practical challenges related to three important problems in mobile distributed services. In addition, I present my efforts towards a formal model for representing mobile distributed services. First, I address the challenge of enhancing the programmability of mobile distributed services. This thesis presents a set of core mechanisms underlying mobile distributed services. I interpret and implement these mechanisms for the domain of crowd-sourced services. A distributed runtime middleware, CSSWare, has been developed to simplify the burden of initiating and managing crowd-sourced services. CSSWare provides a set of domain-specific programming constructs for launching a new service. Service designers may launch novel services over CSSWare by simply plugging in small pieces of service specific code. Particularly, new services can be prototyped in fewer than 100 lines of code. This ease of programming promises to democratize the building of such services. Second, I address the challenge of efficiently supporting the sensing needs of mobile distributed services, and more generally sensor-based applications. I developed ShareSens, an approach to opportunistically merge sensing requirements of independent applications. When multiple applications make sensing requests, instead of serving each request independently, ShareSens opportunistically merges the requests, achieving significant power and energy savings. Custom filters are then used to extract the data required by each application. Third, I address the problem of programming the sensing requirements of mobile distributed services. In particular, ModeSens is presented to allow multi-modal sensing requirements of a service to be programmed separately from its function. Programmers can specify the modes in which a service can be, the sensing needs of each mode, and the sensed events which trigger mode transition. ModeSens then monitors for mode transition events, and dynamically adjusts the sensing frequencies to match the current mode's requirements. Separating the mode change logic from an application's functional logic leads to more modular code. In addition, I present MobDisS (Mobile Distributed Services), an early model for representing mobile distributed services, allowing them to be carefully studied. Services can be built by composing simpler services. I present the syntax and operational semantics of MobDisS. Although this work can be evaluated along multiple dimensions, my primary goal is to enhance programmability of mobile distributed services. This is illustrated by providing the actual code required for creating two realistic services using CSSWare. Each service demonstrates different facets of the middleware, ranging from the use of different sensors to the use of different facilities provided by CSSWare. Furthermore, experimental results are presented to demonstrate scalability, performance and data-contributor side energy efficiency of CSSWare and ShareSens. Finally, a set of experimental evaluation is carried out to measure the performance and energy costs of using ModeSens

Serum Malondialdehyde Levels as a Biomarker of Cellular Injury In Human Fascioliasis

AbstractMacrophages, neutrophils and other phagocytic cells are key components of the antiparasitic, antimicrobial and tumoricidal immune responses. These cells are capable of generating large amounts of reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS have a possible role in the pathogenesis of parasitic disease. Lipid peroxidation is a well-established mechanism of cellular injury and is used as an indicator of oxidative stress in cells and tissues. To examine oxidant status and lipid peroxidation in fascioliasis patients, the malondialdehyde (MDA) (an end-product of lipid peroxidation) has been studied. Serum MDA level was measured in 34 patients infected with Fasciola gigantica and their age and gender were matched to 36 healthy controls. The difference between MDA levels of patients infected with Fasciola gigantica and the control group was statistically significant both in females (P<0.05) and males (P<0.05) with no correlation between age and MDA levels both in females and males of patient and control group. The high infection/control ratio of MDA concentration and the significant correlation strongly indicate the occurrence of oxidative stress and lipid peroxidation as a mechanism of tissue damage in cases of F. gigantica infection

High Performance of Power Cables Using Nanocomposites Insulation Materials

Partial discharges occur the biggest failure problem in power cable insulation due to distortion of electrical stress. In this paper, it has been investigated on the effect of spherical nanoparticles of Barium titanate (BaTiO3) and Clay for enhancing electrostatic field distribution in single and three-core power cables. It has been applied new strategies of nanotechnology techniques for designing innovative polyvinyl chloride insulation materials by using nanocomposites and multi-nanocomposites. Moreover, it has been studied the electrostatic field distribution within power cable nanocomposites insulation in presence of air voids, water voids and cupper impurity voids. The electrostatic field distribution in power cable insulation has been calculated by finite element method (FEM). A comparative study has been investigated on the effect of nanocomposite insulation for enhancing electric field stress in power cables.

Four new tin(II), uranyl(II), vanadyl(II), and zirconyl(II) alloxan biomolecule complexes: synthesis, spectroscopic and thermal characterizations

ABSTRACT. The alloxan as a biomolecule ligand has been utilized to synthesize thermodynamically and kinetically stabilized four new tin(II), uranyl(II), vanadyl(II), and zirconyl(II) complexes. In the complexes, tin(II) ion present is in tetrahedral arrangement, zirconyl and vanadyl(II) ions present are in square pyramid feature but uranyl(II) ion present is in octahedral arrangement and all are coordinated by two bidentate alloxan ligand in complexes. The synthesized alloxan ligand coordinate with central metal(II) ion through oxygen in position C2=O and the nitrogen in position N1 developing a 4-membered chelate ring. Synthesized Sn(II), UO2(II), VO(II), and ZrO(II) complexes via bidentate ligand have been accurately described by various spectroscopic techniques like elemental analysis (C, H, N, metal), conductivity measurements, FT-IR, UV-Vis, 1H-NMR, and TGA. The kinetic thermodynamic parameters such as: E*, ΔH*, ΔS* and ΔG* were calculated using Coats and Redfern and Horowitz and Metzger equations. &nbsp; KEY WORDS: Alloxan, Metal ions, Spectroscopy, Ligand, Coordination, Thermogravimetry &nbsp; Bull. Chem. Soc. Ethiop. 2022, 36(2), 373-385.&nbsp;&nbsp;&nbsp; DOI: https://dx.doi.org/10.4314/bcse.v36i2.11&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp

Design of Multi-Nanoparticles Technique for Enhancing Magnetic Characterization of Power Transformers Cores

The structure of magnetic materials is an essential parameter for specifying magnetic characterization of the transformer core. This paper presents enhancing magnetic characterization of transformer cores by using new nanotechnology techniques. The effective magnetic parameters of new magnetic nanocomposites materials for the transformer cores (single-phase and three-phase) have been predicted based on recent theoretical approaches. The new design, the effects of variant types and concentrations of magnetic multi-nanoparticles on magnetization loss of transformers cores were studied with respect to traditional transformer cores. Optimal types and concentrations of nanoparticles were defined for controlling of reluctance and magnetization loss of transformer cores using multi-nanoparticles technique. A comparative study depicted the industrial features for using multi-nanoparticles against separate nanoparticles in transformers cores

Biomarkers charge-transfer complexes of melamine with quinol and picric acid: Synthesis, spectroscopic, thermal, kinetic and biological studies

AbstractTwo new melamine (MA) charge transfer complexes with quinol and picric acid in aqua media have been synthesized and structurally characterized. The obtained complexes with the general formula [(MA)(acceptor)2] with a 2:1 acceptor:donor molar ratio. Elemental analysis (CHN), electronic spectra, photometric titration, mid infrared spectra, 1H NMR spectra and thermogravimetric analysis (TG) were used to predict the position of the charge transfer interaction between the donating and accepting sites. The MA CT-complexes were antimicrobial assessment against two kinds of bacterial and fungal species

Synthesis, spectroscopic characterizations and DFT studies on the metal complexes of azathioprine immunosuppressive drug

ABSTRACT. A complex of the immunosuppressive drug azathioprine with Cr(II), Mn(II), Fe(II), Zn(II), Cu(II), Ni(II), and Co(II) were synthesized and characterized through spectroscopic and thermal studies. The infrared spectra show the coordination of azathioprine via N(9) to the metal, also, the range around 640–650 cm−1 remains unchanged in the complexes, indicating the possibility that the ether group may not be involved in the binding. Thermogravimetric analysis (TG), thermogravimetric derivational analysis (DTG), and differential thermogravimetric analysis (DTA) have been studied in the temperature range from 0 °C to 1000 °C. The study of pyrolysis showed that all complexes decompose in more than one step and that the final decomposition product is metal oxide. The DFT (density functional theory) with B3LYP/6-31G++ level of theory was used to study the optimized geometry, HOMO→LUMO energy gap, and molecular electrostatic potential map of azathioprine before and after deprotonation. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; KEY WORDS: Azathioprine, Spectral study, Thermal study, Decomposition products, DFT Bull. Chem. Soc. Ethiop. 2022, 36(1), 73-84.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; DOI: https://dx.doi.org/10.4314/bcse.v36i1.

A new simple route for synthesis of cadmium(II), zinc(II), cobalt(II), and manganese(II) carbonates using urea as a cheap precursor and theoretical investigation

ABSTRACT. The MnCO3.H2O, CoCO3.4H2O, ZnCO3, and CdCO3, respectively, were synthesized through a new precise, easy pathway for the reaction of MnI2, CoI2, ZnI2, or CdI2 aqueous solutions with a cheap precursor-urea for 10 h at ~ 70 oC. The IR spectra of reaction products designate the presence of characteristic bands of ionic carbonate, CO32– and absence of the individual bands of urea. The (CO3)2- ion is planar and therefore, it belongs to the D3h symmetry. It is expected to display four modes of vibrations. The stretching vibrations of the type; n(C-O) is observed in the range of (1376-1503) cm-1 while another stretching vibration n(C-O) is observed in the region 1060-1079 cm-1. The out of plane of vibration d(OCO) is observed in the range of (833-866) cm-1 while, the angle deformation bending vibration d(OCO) appear in the range of (708-732) cm-1. The infrared spectra of metal carbonate, show that, this product clearly has an uncoordinated water. The band related to the stretching vibration n(O-H) of uncoordinated H2O is observed as expected in the range of ~ 3000 cm-1. A general mechanism explaining the synthesis of carbonate compounds of cadmium(II), zinc(II), cobalt(II), and manganese(II), are described. Moreover, the DFT outcomes using B3LYP/LanL2DZ (basis set) agree with the experimental results. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; KEY WORDS: Carbonate, CoI2, Infrared spectra, Urea, DFT &nbsp; Bull. Chem. Soc. Ethiop. 2022, 36(2), 363-372. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; DOI: https://dx.doi.org/10.4314/bcse.v36i2.10&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp

Efficient adsorption of Rhodamine B using a composite of Fe3O4@zif-8: Synthesis, characterization, modeling analysis, statistical physics and mechanism of interaction

ABSTRACT. The utilization of a metal organic framework (ZIF-8) modified by Fe3O4 nanoparticles was used to accomplish adsorption of Rhodamine B (RB) from aqueous solutions. SEM, XRD, IR, and BET analyses were all used to characterize the composite (Fe3O4@ZIF-8). The surface area of this adsorbent was&nbsp;478.4 m2/g. X-Ray diffraction spectroscopy was used to detect surface modification utilizing electron microscopy (SEM) scanning with 48 nm in diameter average particle size according to a statistical physics method. Fe3O4@ZIF-8 appears to have dispersive interactions and pore characteristics, according to quantum chemistry simulations. On the adsorption of RB, the influences of contact time, adsorbent quantity, dye concentration, and temperature were studied. The Langmuir and Freundlich adsorption isotherm models were used to study the adsorption isotherms. Anticipated overall adsorption potential was 647.5 mg/g, with a zero-charge point (pHPZC) of 4.3. The adsorption isotherm was fitted using Langmuir whereas pseudo second order was used to match the kinetics. Energy of adsorption (Ea) is 28.7 kJ/mol, indicating a chemisorption phase. The adsorption process is endothermic and unpredictable, according to thermodynamic experiments. It was also looked into using ethanol as a solvent in the desorption of deposited cationic dye. &nbsp; KEY WORDS: Fe3O4@ZIF-8, Rhodamine B, Adsorption models, Thermodynamics &nbsp; Bull. Chem. Soc. Ethiop. 2023, 37(1), 211-229.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; DOI: https://dx.doi.org/10.4314/bcse.v37i1.17 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp

Mortality of emergency abdominal surgery in high-, middle- and low-income countries

Background: Surgical mortality data are collected routinely in high-income countries, yet virtually no low- or middle-income countries have outcome surveillance in place. The aim was prospectively to collect worldwide mortality data following emergency abdominal surgery, comparing findings across countries with a low, middle or high Human Development Index (HDI). Methods: This was a prospective, multicentre, cohort study. Self-selected hospitals performing emergency surgery submitted prespecified data for consecutive patients from at least one 2-week interval during July to December 2014. Postoperative mortality was analysed by hierarchical multivariable logistic regression. Results: Data were obtained for 10 745 patients from 357 centres in 58 countries; 6538 were from high-, 2889 from middle- and 1318 from low-HDI settings. The overall mortality rate was 1⋅6 per cent at 24 h (high 1⋅1 per cent, middle 1⋅9 per cent, low 3⋅4 per cent; P < 0⋅001), increasing to 5⋅4 per cent by 30 days (high 4⋅5 per cent, middle 6⋅0 per cent, low 8⋅6 per cent; P < 0⋅001). Of the 578 patients who died, 404 (69⋅9 per cent) did so between 24 h and 30 days following surgery (high 74⋅2 per cent, middle 68⋅8 per cent, low 60⋅5 per cent). After adjustment, 30-day mortality remained higher in middle-income (odds ratio (OR) 2⋅78, 95 per cent c.i. 1⋅84 to 4⋅20) and low-income (OR 2⋅97, 1⋅84 to 4⋅81) countries. Surgical safety checklist use was less frequent in low- and middle-income countries, but when used was associated with reduced mortality at 30 days. Conclusion: Mortality is three times higher in low- compared with high-HDI countries even when adjusted for prognostic factors. Patient safety factors may have an important role. Registration number: NCT02179112 (http://www.clinicaltrials.gov)