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Introduction Long-term use of laxatives may have side effects such as bloating, allergic reaction, abdominal pain, metabolic disturbances, and hepatotoxicity. In this study, we have compared the efficacy of herbal medicine Nucarb, a combination of activated charcoal, calcium sennosides, peppermint oil, fennel oil, rhubarb extract, and purified sulfur, in relieving constipation. Methods This longitudinal study was conducted in multiple cities of Pakistan from April 2021 to June 2021. A total of 1000 patients, of either gender between age group 18 and 75 years, with complete spontaneous bowel movement of less than or equal to two times per week, were enrolled in the study. Participants were prescribed two tablets of Nucarb once daily (OD) at bedtime for the first seven days, followed by one tablet of Nucarb OD at bedtime for the following seven days. They were asked to return for follow-up after 14 days. Results There was a statistically significant improvement in all six components of constipation. After 14 days, the severity of constipation reduced by 80.70%, the sensation of straining was reduced by 72.69%, and the feeling of incomplete evacuation was reduced by 71.87%. There was no adverse event reported. Conclusion Nucarb is efficacious in reducing the severity of constipation, sensation of straining, bloating and abdominal pain, feeling of incomplete evacuation, and difficulty in passing gas. Since it is a herbal product, it can be safely used in all populations.
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The phenomenon of dynamic soaring, as exhibited by soaring birds, has long been a biological inspiration for aerospace and control engineers. If this fascinating phenomenon, which allows soaring birds to perform almost unpowered flight using wind shear, can be mimicked by unmanned aerial vehicles (UAVs), then there is substantial potential for technological and economic enhancement of UAV performance. Although there has been a considerable amount of research covering the modeling, optimization, control and simulation aspects of different UAVs performing dynamic soaring, there is little to no conclusive work analyzing the stability of such UAVs in soaring orbits. In this paper we present a comprehensive framework for determining the stability of soaring UAVs utilizing both linear (Floquet-based) and nonlinear (contraction theory-based) techniques. Floquet stability analysis was inconclusive, which led to the use of a nonlinear contraction formulation to reach a conclusive stability assessment for an actual nonlinear fixed-wing UAV performing dynamic soaring. Furthermore, parametric variation along with numerical simulations were conducted to ascertain the response of the actual nonlinear system when perturbed from the nominal motion studied in this paper. The analysis and simulations revealed that the system possesses instability as the UAV motion diverges from its nominal trajectory and follows an undesirable path. From this result we conclude, for the first time in the literature as far as we are aware, that UAVs performing dynamic soaring in an optimal way to reduce wind shear requirements are inherently unstable. The results of this work suggest that mimicking of dynamic soaring by UAVs will require careful investigation of tracking and regulatory controls that need to be implemented.