Jacobsson G.,Skaraborg Hospital |
Nasic S.,Center for Research and Development
Scandinavian Journal of Infectious Diseases | Year: 2012
Background: Short-term mortality from invasive Staphylococcus aureus infections (ISA) is high. Death rates from 20% to 60% are reported. Long-term outcome has not been investigated. Studies of other critical illnesses have demonstrated incremental health effects that persist after hospital discharge. Several researchers have proposed that evaluation of mortality secondary to sepsis should take place after 1 y. Methods: We performed an observational, prospective, population-based study of long-term mortality and recurrence in a cohort of ISA patients during 2 y. Results: One hundred and fifty-seven patients were included. All-cause mortality after 1 y was 37.6% and after 3 y was 45.5%. The multivariate survival analysis explored different independent factors for short-term compared to long-term mortality. Age, comorbidity, and place of acquisition were the determinants of long-term outcome. In contrast, infection-related factors such as disease severity and systolic blood pressure determined short-term mortality. The relapsereinfection rate was 11.2% (16 in 143 episodes in 127 patients living 4 weeks after inclusion). Predictive factors for relapsereinfection in a univariate analysis were joint prosthesis (28.6%, p = 0.027), haemodialysis (27.8%, p = 0.017), kidney disease (22.2%, p = 0.015), and healthcare- and nosocomial-related infection (18.3%, p = 0.029). No association to length of antibiotic therapy and relapsereinfection rate was observed, nor any sex differences. The majority of relapsesreinfections (11 of 16) occurred during the first 11 months after the initial episode. Conclusion: Patients with ISA infections, irrespective of age, suffer a high long-term mortality and recurrence rate. © 2012 Informa Healthcare.
Madheswaran M.,Center for Research and Development
Journal of Engineering and Applied Sciences | Year: 2011
A Hybrid Wave Pipelining Phase Accumulator for Direct Digital Synthesizer is presented in this paper. Conventional Pipelining requires additional registers and it results in more area, power dissipation and clock routing complexity. Wave-pipelining does not have any of these disadvantages and it can be used to speed up the circuits without insertion of storage elements. The clock period in conventional pipeline scheme is proportional to the maximum delay while in hybrid wave-pipelining it is proportional to the maximum delay difference. To prove the better performance of the Hybrid wave pipelining Phase Accumulator DDS architecture compared it favorably with several existing DDS architecture. The focus of this paper is on design and analysis of hybrid wave pipelining Phase Accumulator DDS, using XilinxISE9.2i. © 2006-2011 Asian Research Publishing Network (ARPN).
Ramalingam S.,Avc College |
Periandy S.,Tagor Arts College |
Elanchezhian B.,Avc College |
Mohan S.,Center for Research and Development
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2011
FT-IR (4000-100 cm-1) and FT-Raman (4000-100 cm-1) spectra of solid sample of 4-chloro-2-fluoro toluene (4Cl2FT) have been recorded using Bruker IFS 66 V spectrometer. Ab initio-HF (HF/6-311++G (d, p)) and DFT (B3LYP/6-311++G and B3PW91/6-311++G (d, p)) calculations have been performed giving energies, optimized structures, harmonic vibrational frequencies, depolarization ratios, IR intensities, Raman activities. The vibrational frequencies are calculated and scaled values are compared with FT-IR and FT-Raman experimental values. The isotropic HF and DFT analyses showed good agreement with experimental observations. The differences between the observed and scaled wave number values of most of the fundamentals are very small in B3LYP than HF. Comparison of the simulated spectra provides important information about the ability of the computational method (B3LYP) to describe the vibrational modes. The influences of substitutions on the geometry of molecule and its normal modes of vibrations have also been discussed. The changes made by substitutions on the benzene are much responsible for the non-linearity of the molecule. This is an attractive entity for the future studies of non-linear optics. © 2010 Elsevier B.V. All rights reserved.
Madheswaran M.,Center for Research and Development
Circuits, Systems, and Signal Processing | Year: 2013
The improved Direct Digital Synthesizer (DDS) using the Hybrid Wave Pipelining (HWP) technique and COordinate Rotation DIgital Computer (CORDIC) algorithm for Software Defined Radio (SDR) is presented in this paper. In order to achieve high throughput, the hybrid wave pipelining technique is adopted. The HWP can be used to speed up the circuits without insertion of storage elements. The CORDIC algorithm is used for phase-to-amplitude conversion and utilized for dynamic transformation rather than Read Only Memory (ROM) static addressing. The frequency resolution and phase resolution are achieved as 0.023 Hz and 0.088 degree, respectively, at the maximum operating frequency of 199.288 MHz for the proposed DDS architecture. The spectral purity of the proposed design has been improved to 114 dBc with a throughput of 94 %. This paper is focused on the design and implementation of DDS using hybrid wave pipelining with CORDIC approach to target on Xilinx Spartan 3 (XC3S400-5PQ208) Field Programmable Gate Array (FPGA) with a speed grade of -5. The proposed DDS design reduces the gate count from 49.4 % to 18.2 % as compared to the conventional pipelined Read Only Memory Look Up Table (ROMLUT) DDS method. The throughput of the proposed method has been improved from 78 % to 94 % and 55 % of total power reduction as compared with conventional DDS. The performance of the improved DDS architecture is compared with several existing DDS architectures and it is found that the present design is outperforming and can be used for software defined radios. © 2012 Springer Science+Business Media, LLC.
Zuniga R.N.,Center for Research and Development |
Pedreschi F.,University of Santiago de Chile
Food and Bioprocess Technology | Year: 2012
The study of the equilibrium is needed not only for modeling of the osmotic process as a unit operation but also for a better understanding of the mass transfer mechanisms involved in this kind of systems. A true equilibrium state usually takes very long time to achieve; therefore, a pseudo-equilibrium state is often employed. Experimental pseudo-equilibrium states for water loss and solid gain during the osmotic dehydration of apple slices (5 × 50 × 50 mm 3) at different osmotic syrup concentrations (30%, 40%, 50%, and 60% (w/w) of sucrose) were evaluated. Four empirical mathematical methods (Slopes, Azuara, Zugarramurdi and Lupín, and Equal concentration) were used in order to calculate the pseudo-equilibrium values obtained and then to compare them against to the experimental ones. Additionally, the effective diffusion coefficients for water and sucrose were calculated by using those pseudo-equilibrium values. Experimental pseudo-equilibrium values increased with concentration of the osmotic syrup, ranged between 24% and 56% for water loss and 11% and 28% for solid gain; the predicted pseudo-equilibrium values followed the same trend. The decreasing order of accuracy for pseudo-equilibrium values and effective diffusion coefficients, among the methodologies evaluated, was Equal concentration method & Azuara method & Slopes method & Zugarramurdi and Lupín method. Although the Equal concentration method has no theoretical accuracy, it is independent of the kinetic data presenting a higher advantage over the other three mathematical methods evaluated. © 2011 Springer Science + Business Media, LLC.