Background and Objective: Fixed drug eruption (FDE) is one kind of drug rashes that is characterized by re-appearance of the lesions on the same sites after re-exposure to the causative drug. This study was performed to evaluate the epidemiologic characteristics of FDE. Materials and Methods: This descriptive study was done on a series of 100FDE cases, whom were admitted at the outpatient dermatology clinic of Hazrat-e-Rasoul Hospital over a six-year period. The primary diagnosis of FDE was suggested according to clinical findings including a remaining hyperpigmentation at the site of healed skin lesion(s). Oral challenge test with a single low dose administration of the suspected drug was used to confinn the diagnosis. Recurrence of the lesion(s) at the same body area(s) was considered as positive result. Results: Most commonly causative agents were co-trimoxazole and codein, which were found in 88% and 3% FDE cases; respectively. The most common site of involvement was penile glans in 57.7% of male patients and trunk in 48.3% of females. In one patient, reaction to multiple drugs including co-trimoxazole, codein and tetracycline was observed and after re-challenge with each drug, re-appearance of the skin lesion at the same site was evident. Several patients reported concomitant acetaminophen intake, but there was no reaction to that drug. Conclusion: Co-trimoxazole is the most common cause of FDE.      

Let y"=f(x,y,y') be a 2nd order ODE. By Cartan equivalence method, we will study the local equivalence problem under the transformations group of time-Fixed coordinates. We are going to solve this problem by an applicable method which has been recognized by R. Gardner, and classify them.

The problem of consensus in fractional order single-integrator multi-agent systems has been studied in this paper. The effect of memory is considered using the Riemann-Liouville fractional derivative in the dynamics of the agents. In order to achieve convergence among the agents, a fractional order control protocol based on the error signal between neighboring agents is proposed. Using Lyapunov's stability theorem, a Lyapunov function is introduced that shows that the agents converge over a specified settling time and the upper bound of the settling time is obtained. The merit of the proposed bound for the settling time is that it is independent of the initial conditions. Finally, some simulations are provided to confirm the introduced method.

Evaluation of seismic behavior of offshore platforms is one of the important design steps in seismic regions. Nevertheless, because of complication and time cost of these methods, engineers usually do not study them deeply. Endurance time (ET) method is a good solution for this problem. In this method, with acceptance of a reasonable region of errors, the time of analysis can be reduced considerably. Besides with one ET analysis, the behavior of structure can be evaluated in different seismic levels. In this paper, the ET and other usual methods in standards are introduced and then the seismic behavior of three platforms is compared with ET and response spectrum method. In this comparison, the acceleration function which is generated base on Iranian cod (2800 standard), is used and the differences are considered in relation to spectral analysis of 2800 standard. The results show appropriate conformity between two methods.

Chlorinated phenols in many industrial effluents are usually difficult to be removed by conventional biological treatment processes. Performance of the aerobic sequencing batch reactor treating 4- chlorophenol containing wastewater at different loadings rates from 0.0075 to 1.2 g4CP/L.d was evaluated. The sequencing batch reactor was operated with fill, react, settle and decant phases in the order of 10:370:90:10 min, respectively, for a cycle time of 8 h at 10 days solid retention time and 16 h hydraulic retention time in the stable period. The effects of 4-chlorophenol loadings on the 4- chlorophenol and chemical oxygen demand removal percents, yield coefficient (Y), biomass variation and sludge volume index were investigated. High chemical oxygen demand removal efficiencies (95±3.5%) and approximately complete 4-chlorophenol removal (>99%) were observed even in the absence of growth substrate. The degradation of 4-chlorophenol led to formation of 5-chloro-2-hydroxymuconic semialdehyde, which was more oxidized, indicating complete disappearance of 4-chlorophenol via metacleavage pathway. A compact sludge with excellent settleability (sludge volume index=47±6.1 mL/g) developed during entire acclimation period. High removal efficiencies with sequencing batch reactor may be due to enforced short term unsteady state conditions coupled with periodic exposure of the microorganisms to defined process conditions which facilitate the required metabolic pathways for treating xenobiotics containing wastewater.

Planning the flight path for a fleet of Fixed-wing unmanned aerial vehicles during search and rescue operations poses a significant challenge as it requires minimizing search time and optimizing the formation of the unmanned aerial vehicles. This paper proposes a novel integration of a leaderfollower formation flight technique for multiple Fixed-wing unmanned aerial vehicles with a minimumtime search path planning algorithm. In the first step, the proposed algorithm, based on continuous ant colony optimization, plans a sequence of safe and feasible waypoints for the leader while determining appropriate azimuth angles for the followers. In the next step, the algorithm utilizes a nonlinear threedegree-of-freedom model, developed based on a leader-follower formation flight technique, to plan the followers’ flight paths. Applying Dubins curves based on kinematic constraints of the unmanned aerial vehicles not only reduces computational time but also ensures the feasibility of the best search paths between planned waypoints. Furthermore, in the presence of static obstacles, a developed function in the planning process addresses collision and obstacle avoidance constraints. The effectiveness and performance of the suggested method in detecting targets in minimum-time search missions and the ability of the planner to reconfigure the formation of unmanned aerial vehicles in cluttered environments are demonstrated through comprehensive simulation studies and Monte Carlo analysis.