Microstrip Line Discontinuities Simulation at Microwave Frequencies

Microwave and Millimeter wave integrated circuits (MICs) have experienced a tremendous growth over the last 50 years. Microstrip line is one of the popular lines in these MICs. Due to the layout necessities, an electromagnetic wave that propagates down a microstrip line may encounter discontinuities such as T-junctions, Bends and vias. A simulation model is presented here for analysing these discontinuities in microstrips through Sonnet Software. The parameters of microstrip lines are determined from the empirical formulae which are based on full wave analysis. The simulation work has been performed on Alumina substrate. The discontinuities are simulated and compensated which gives important results for designing high frequency microwave circuits. Key Words: Microwave and millimeter wave integrated circuits (MICs), microstrip line, microstrip line discontinuities, T-junctions, bends, steps in width, full wave analysis, substrate permittivity and sonnet software

Awareness and perceptions of electroconvulsive therapy among psychiatric patients: a cross-sectional survey from teaching hospitals in Karachi, Pakistan

<p>Abstract</p> <p>Background</p> <p>Electroconvulsive therapy (ECT) is shown to be effective in many psychiatric illnesses, but its distorted projection by the Pakistani media and its unregulated use by many physicians across the country have adversely affected its acceptability. Given this situation we aimed to assess the awareness and perceptions regarding ECT as a treatment modality among the psychiatric patients.</p> <p>Methods</p> <p>This was a questionnaire based cross-sectional study carried out at 2 tertiary care hospitals in Karachi, Pakistan.</p> <p>Results</p> <p>We interviewed 190 patients of which 140 were aware of ECT. The study showed that the level of education had a significant impact on the awareness of ECT (p = 0.009). The most common source of awareness was electronic and print media (38%), followed by relatives (24%) and doctors (23%). Physical injuries (42%) and neurological (12%) and cognitive disturbances (11%) were the commonly feared side effects. The most popular belief about ECT was that it was a treatment of last resort (56%). Thirty-nine percent thought that ECT could lead to severe mental and physical illness and 37% considered it inhumane. Patients' willingness to receive ECT was dependant on whether or not they were convinced of its safety (p = 0.001) and efficacy (p = 0.0001).</p> <p>Conclusion</p> <p>We identified a serious lack of dissemination of information regarding ECT by the psychiatrists and the mental health care providers. This may be the result of an inadequate postgraduate training in Pakistan or just a lack of concern about the mentally ill patients. The media seemed to be the major source of information for our patients. We also saw the prevalence of a variety of myths regarding ECT in our society, which we feel may be responsible for the patients' adverse attitudes. Given the widespread applicability of ECT there is a dire need to dispel these misconceptions and improve its acceptability.</p

Crystal structure of 6-amino-4-(3-bromo-4-methoxyphenyl)-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile dimethyl sulfoxide monosolvate

In the pyrazole molecule of the title solvate, C15H13BrN4O2·C2H6OS, the dihedral angle between the benzene ring and the mean plane of the dihydropyrano[2,3-c]pyrazole ring system [r.m.s deviation = 0.031 (2) Å] is 86.71 (14)°. In the crystal, the pyrazole molecules are linked by N—H...N hydrogen bonds, forming a layer parallel to (10-1). The pyrazole and dimethyl sulfoxide molecules are connected by an N—H...O hydrogen bond

Crystal structure of 2-[2-(benzyloxy)benzylidene]malononitrile

In the title benzylidenemalononitrile derivative, C17H12N2O, the dihedral angles between the central benzene ring and the Y-shaped C=C(CN)2 group (r.m.s. deviation = 0.006 Å) and the terminal benzene ring are 12.72 (8) and 37.60 (11)°, respectively. The Car—O—Csp3—Car torsion angle is −174.52 (13)° and the major twist between the aromatic rings occurs about the Csp3—Car bond. Weak aromatic π–π stacking [centroid–centroid separation = 3.7784 (13) Å; slippage = 1.21 Å] between inversion-related pairs of the central benzene rings is observed in the crystal

Outcomes of COVID-19 infection in patients with hematological malignancies- A multicenter analysis from Pakistan

Purpose: COVID-19 infection resulting from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began to spread across the globe in early 2020. Patients with hematologic malignancies are supposed to have an increased risk of mortality from coronavirus disease of 2019 (COVID-19) infection. From Pakistan, we report the analysis of the outcome and interaction between patient demographics and tumor subtype and COVID-19 infection and hematological malignancy. Patients and methods: This multicenter, retrospective study included adult patients with a history of histologically proven hematological malignancies who were tested positive for COVID-19 via PCR presented at the oncology department of 5 tertiary care hospitals in Pakistan from February to August 2020. A patient with any known hematological malignancy who was positive for COVID-19 on RT-PCR, was included in the study. Chi-square test and Cox-regression hazard regression model was applied considering p ≤ 0.05 significant. Results: A total of 107 patients with hematological malignancies were diagnosed with COVID-19, out of which 82 (76.64%) were alive, and 25 (23.36%) were dead. The significant hematological malignancy was B-cell Lymphoma in dead 4 (16.00%) and alive group 21 (25.61%), respectively. The majority of the patients in both the dead and alive group were on active treatment for hematological malignancy while they came positive for COVID-19 [21 (84.00%) & 48 (58.54%) p 0.020]. All patients in the dead group were admitted to the hospital 25 (100.00%), and among these, 14 (56.00%) were admitted in ICU with a median 11 (6-16.5) number of days. Among those who had contact exposure, the hazard of survival or death in patients with hematological malignancies and COVID-19 positive was 2.18 (CI: 1.90-4.44) times and 3.10 (CI: 2.73-4.60) times in patients with travel history compared to no exposure history (p 0.001). Conclusion: Taken together, this data supports the emerging consensus that patients with hematologic malignancies experience significant morbidity and mortality resulting from COVID-19 infection