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In this paper the identification and control for the impressed current cathodic protection (ICCP) system are present. Firstly, an identification model using an Adaptive Neuro-Fuzzy Inference Systems (ANFIS) was implemented. The identification model consists of four inputs which are the aeration flow rates, the temperature, conductivity, and protection current, and one output that represented by the structure-to-electrolyte potential. The used data taken from an experimental CP system model, type impressed current submerged sample pipe carbon steel. Secondly, two control techniques are used. The first control technique use a conventional Proportional-Integral-Derivative (PID) controller, while the second is the fuzzy controller. The PID controller can be applied to control ICCP system and quite easy to implement. But, it required very fine tuning of its parameters based on the desired value. Furthermore, it needed time response more than fuzzy controller to track reference voltage. So the fuzzy controller has a faster and better response.

ABSTRACT Background: The present study is based on two assumptions. First is the racial and ethnic differences in the presentation of rheumatoid arthritis (RA) and its response to drugs. And the second is the interaction between nonsteroidal anti-inflammatory drugs (NSAIDs) and the disease modifying antirheumatic drugs (DMARDs) particularly methotrexate (MTX) with the possibility of enhanced toxicity. Objectives: to investigate the efficacy and toxicity of MTX alone or in combination with diclofenac in the treatment of RA. Methods: Design: A three month randomized comparative clinical trial Setting: Rheumatology Unit at the Teaching Hospital and the Department of Pharmacology, College of Medicine, University of Basrah, Basrah, Iraq. Patients: Patients with moderate to severe RA were classified into, Group I: received MTX (7.5 mg orally as a single weekly dose). Group II: received MTX single weekly dose plus diclofenac sodium 100 SR tablets once daily Measurements and evaluation Pain, morning stiffness, joint function (number of the swollen and tender joints), patients and physician global assessment, radiological evaluation (according to modified Sharp score for joint space narrowing and erosions), ACR criteria for progression and remission of RA, laboratory findings (complete blood picture and ESR, blood groups, Hb electrophoresis, AST, ALT, blood urea) and drug adverse effects were evaluated. Results: Twenty eight patients with moderate to severe RA were randomly allocated into two treatment groups as cited in the Methods. Only 25 patients managed to complete the 12 week treatment course. Oral MTX (7.5 mg) resulted in a statistically significant clinical improvement after 12 weeks of treatment. The improvement seems to be time dependent. The average percent improvement in six clinical parameters mounted to about 35% compared to the baseline measurements. The 20% improvement at 12 weeks of treatment using ACR criteria involved 42.8% of patients. Radiological findings (joint space narrowing and erosion) increased slightly by only 5.7% over the 12 week treatment period. No significant change in all laboratory parameters measured. No important side effects peculiar to MTX could be figured out. Concurrent administration of diclofenac (sustained release formulation) with MTX resulted in a paradoxical finding. Instead of enhancing efficacy or toxicity of MTX, diclofenac reduced the efficacy of MTX from 35.25% to only 15.78% at the end of the treatment period. The two groups, however, differed in some aspects e.g. disease duration and severity, and the type of blood groups which might possibly have contributed to this difference. The ACR20 in the combination group is 36.3% (compared to 42.8% in MTX group). Radiological findings progressed by 48.3% in the joint space narrowing and erosion. When results of MTX and MTX+diclofenac groups were analyzed according to disease severity and blood groups, it was found that the response of patients with severe but not moderate disease was comparable in the two groups. Blood group (A) seems to be associated with enhanced response and group (O) with a reduced one. Conclusion: Methotrexate 7.5 mg as a single oral dose per week produced a significant clinical improvement over the 12 week treatment period. The drug seems to be well tolerated with no important adverse effects. In contrast to what is expected, sustained formulation of diclofenac sodium reduced the efficacy of MTX. The latter finding, if proved to be true, could have an important clinical implication.

ABSTRACT Background: Racial variation in the clinical presentation of rheumatoid arthritis (RA) and its response to treatment is well known. Ethnicity and associated socioeconomic factors make it necessary to study the effectiveness of the antirheumatic drugs such as sulfasalazine (SSZ) in our RA patients, and to what extent it interacts with the nonsteroidal anti-inflammatory drug (NSAID); diclofenac. Objective: To investigate the efficacy and toxicity of sulfasalazine alone or in combination with diclofenac in the treatment of moderate to severe RA. Methods: A three month-randomized clinical trial was conducted on patients with moderate to severe RA: Group I: received SSZ (500 mg orally twice daily), and Group II: received SSZ plus diclofenac sodium 100mg SR tablets once daily. Evaluation involved: pain, morning stiffness, joint function, patients and physician global assessment, radiological assessment, ACR criteria, laboratory findings and drug adverse effects. Results: Only 17 patients out of 20, managed to complete the 12 week treatment course. Oral SSZ (500mg twice daily for 3 months) resulted in a statistically significant clinical improvement after 12 weeks of treatment. The average percent improvement in six clinical parameters was 21.1%. The 20% improvement using ACR criteria involved 11% of patients. The improvement occurred especially in the number of swollen joints and in joint pain. The overall improvement that occurred two weeks after treatment with SSZ continued at the same level over the 12 week treatment period. No statistically significant changes were detected in the laboratory parameters measured including ESR. No radiological progression was found 12 weeks after treatment in joint space narrowing and joint erosion. SSZ reduced symptoms reported by patients before treatment by 57.4%. Diclofenac as a sustained release formulation administered concomitantly with SSZ did not change the improvement caused by SSZ as measured by the six clinical parameters (23% versus 23.4%). However, the ACR20 increased from 11% to 25%. No effect on laboratory measurements was found. Diclofenac in combination with SSZ reduced the symptoms reported by patients by 70.6% compared with 57.4% by SSZ alone. Conclusion: SSZ treatment for 12 weeks caused mild to moderate improvement in all measured clinical parameters, especially in the number of swollen joints and in joint pain. Diclofenac as a sustained release formulation, given with SSZ, did not change the improvement caused by SSZ as measured by six clinical parameters, although it increased the ACR20 of SSZ from 11% to 25%.

The strain relief and dislocation motion in III-nitride films that are grown on step-free 4H-SiC mesas are studied. The results show that the nucleation of threading dislocations in the absence of interfacial steps is an extremely difficult process, which proves that the strain relief for such III-nitride films is not dominated by the greater excess stress driving dislocation tilt.

We report on peculiar magnetic hysteresis behavior of Ru0.25Cr0.75O2 thin films. We describe three unusual magnetic phenomena inherent to this material; (i) intrinsic positive exchange bias in a single phase epitaxial thin film ferrimagnet with the absence of a clear and distinct magnetic-magnetic interface, (ii) field modulation of the shifted M(H) loop along the field axis direction, and (iii) inverted hysteresis loops in which the overall area of the loop is nearly zero over the entire field cycle. These results can be understood within the context of a very unusual interface of the epitaxial film with the TiO2 (001) substrate. [ABSTRACT FROM AUTHOR]

We investigated multilayer and bilayer Ni/Si thin films by nanodifferential scanning calorimetry (nano-DSC) at ultrarapid scan rates, in a temperature-time regime not accessible with conventional apparatus. DSC experiments were completed at slower scan rates as well, where it was possible to conduct parallel rapid thermal annealing experiments for comparison. Postexperimental characterization was accomplished by x-ray diffraction, and by transmission electron microscopy (TEM) and energy-filtered TEM of thin cross sections prepared by focused ion beam milling. We found that rate of heating has a profound effect on the resulting microstructure, as well as on the DSC signal. After heating to 560 °C at 120 °C/s, the general microstructure of the multilayer was preserved, in spite of extensive interdiffusion of Ni and Si. By contrast, after heating to 560 °C at 16 000 °C/s, the multilayer films were completely homogeneous with no evidence of the original multilayer microstructure. For the slower scan rates, we interpret the results as indicating a solid state diffusion-nucleation-growth process. At the higher scan rates, we suggest that the temperature increased so rapidly that a metastable liquid was first formed, resulting in complete intermixing of the multilayer, followed by crystallization to form solid phases. The integrated DSC enthalpies for both multilayer and bilayer films are consistent with this interpretation, which is further supported by thermodynamic predictions of metastable Ni/Si melting and solid state Ni/Si interdiffusion. Our results suggest that use of heating rates >10 000 °C/s may open new avenues for intermetallic micro- and nanofabrication, at temperatures well below those prevailing during explosive silicidation. [ABSTRACT FROM AUTHOR]