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In this paper, a two Degrees of freedom manipulator in the form of Quanser QUBE-Servo 2 system is used. It is an unstable system having non-minimum phase with right half s-plane pole and zero. The conventional controllers did not achieve the loop robustness for these types of systems. In this work, a Fractional-order proportional derivative (FOPDD) controller is proposed for the system whose mathematical model is made up of two loops where inner and outer loops are used for pendulum and rotary arm position respectively. The method of partial cancellation having a pre-compensator is used for non-minimum phase zeros of the system. Further, the parameters are selected using global stability region plots in which the stability of the system is shown using Riemann surface. The integral error criterion including Integral Absolute Error (IAE), Integral Square Error (ISE) and Integral Time Absolute Error (ITAE); and other performance metrics such as rise time, settling time, overshoot and undershoot are used to compare the robustness of the controllers under nominal environment, trajectory tracking and external disturbances. The simulation results indicate that the proposed FOPDD controller outperforms other existing controllers in terms of performance specifications which further justifies its usage in real-time applications.

Objective(s): 18F-FDG PET/CT has been used to characterize the primary lesion and staging in head and neck cancers (HNC). However, prior studies for detecting distant metastasis and synchronous tumors are sparse, especially in Indian context. To investigate the frequency and distribution of head and neck carcinomas, distant metastases and synchronous malignancies detected in HNC in a north Indian population.Methods: Medical records and whole body 18F-FDG PET/CT examinations performed for initial staging on a total of 281 newly diagnosed HNC patients between 01/2019 to 31/6/2023 in North India were retrospectively analyzed and reviewed to look for distant metastasis and synchronous tumors.Results: On whole body 18F-FDG PET/CT, distant metastases were detected in 33 (11.7%) patients, all with locally advanced primary tumors corresponding to T category 3 and 4. Lung (6%) and bone (~6.7%) were the most common sites of distant metastasis. In nine patients metastases were detected below the diaphragm. Synchronous malignancies were discovered and histopathologically proven in 22 (7%) patients. Lung carcinoma was the most common synchronous tumor, detected in 9 patients. In seven patients synchronous tumour was detected outside the aerodigestive tract, of which four were below the diaphragm.Conclusions: Of the distant metastasis diagnosed in 11.7% of HNC patients with TNM tumor category T3 and T4, 3% of metastasis lesions were detected below the diaphragm. Synchronous malignancy was diagnosed in 7% patients irrespective of primary HNC stage. These findings demonstrate the advantage of using whole body 18F-FDG PET/CT as an ideal and preferred modality for initial staging and screening of HNC patients since detection of distant metastasis or a synchronous malignancy changes the management approach in these patients.

Objective: To study outcomes for patients after they are discharged from Community treatment orders (CTO) including rate of relapse, median time to relapse and to identify the risk factors associated with relapse. Method: The study population included patients discharged from CTO from July 2017 to December 2021, managed by a major metropolitan* case management team (CMT). The data were collected from electronic medical records (EMR). Descriptive analysis was conducted to study the sample characteristics. Logistic regression using univariate and multivariate analysis was performed to examine the associations between factors related to relapse. Results: A total of 128 patients were studied. The relapse rate was 27.4% with median time to relapse of 72 days. Poor insight, poor treatment compliance, duration of CTO and number of CMT contacts were significantly associated with relapse while substance use, psychiatric comorbidities and psychosocial factors were not. Conclusions: The findings suggest that people who relapsed had poor insight and poor medication adherence, had CTO for a longer period and had frequent contact from CMT even after discharge from CTO. [ABSTRACT FROM AUTHOR]