Guaranteed Reachability on Riemannian Manifolds for Unknown Nonlinear Systems

Determining the reachable set for a given nonlinear system is criticallyimportant for autonomous trajectory planning for reach-avoid applications andsafety critical scenarios. Providing the reachable set is generally impossiblewhen the dynamics are unknown, so we calculate underapproximations of such setsusing local dynamics at a single point and bounds on the rate of change of thedynamics determined from known physical laws. Motivated by scenarios where anadverse event causes an abrupt change in the dynamics, we attempt to determinea provably reachable set of states without knowledge of the dynamics. Thispaper considers systems which are known to operate on a manifold.Underapproximations are calculated by utilizing the aforementioned knowledge toderive a guaranteed set of velocities on the tangent bundle of a completeRiemannian manifold that can be reached within a finite time horizon. We theninterpret said set as a control system; the trajectories of this control systemprovide us with a guaranteed set of reachable states the unknown system canreach within a given time. The results are general enough to apply on systemsthat operate on any complete Riemannian manifold. To illustrate the practicalimplementation of our results, we apply our algorithm to a model of a pendulumoperating on a sphere and a three-dimensional rotational system which lives onthe abstract set of special orthogonal matrices.

The Association Between Arsenic Levels and Oxidative Stress in Myocardial Infarction: A Case–Control Study

Cardiovascular diseases (CVDs) are known as the first causes of death throughout the world, and mainly myocardial infarction (MI), lead to 7.4 million deaths annually. Atherosclerosis is the major underlying cause of most CVDs. However, exposure to heavy metals, among other factors, deserves further attention as a risk factor for CVDs. This study was designed to evaluate the levels of arsenic (Ars) in myocardial infarction (MI) patients and healthy individuals as well as assess the association between the incidence of MI and Ars, total antioxidant capacity (TAC), and oxidative stress. This case-control study was conducted among patients with MI (n = 164) and normal individuals (n = 61) at Shafa Hospital in Kerman, Iran. Patients were classified into two groups, including coronary artery blocks above 50% (CAB > 50%, n = 83) and coronary artery blocks less than 50% (CAB < 50%, n = 83) based on their angiography findings. The demographic characteristics, clinical history, biochemical parameters, and serum Ars and TAC levels were evaluated. In the present study, both CAB groups had significantly reduced levels of TAC compared with the control. Furthermore, TAC was lower in the CAB > %50 group compared to the CAB < %50 group. Ars levels were significantly higher in both CAB groups compared with the control. There was a significant positive relationship between CAB and Ars, BG, HbA 1 c, urea, creatinine, TG, TC, and LDL-c, as well as a negative relationship between HDL-c and TAC. Moreover, TAC levels showed a significant inverse correlation with Ars, HbA 1 c, and creatinine, and a positive correlation with HDL-c. As risk factors, Ars, hs-CRP, TG, TC, and LDL-c enhance the severity of the disease, and HDL-c and TAC decrease the disease severity. Moreover, ROC curve analysis revealed that the highest AUC for the CAB > %50 (AUC = 78.29), and cytotoxic levels for both CAB groups (Ars ≥ 0.105 ppm), and no significant differences were found between the two groups. Our findings suggest that Ars at ≥ 0.105 ppm is able to increase the risk of MI through the increased OS and decreased TAC.

Characterization of urban aerosol pollution before and during the COVID-19 crisis in a central-eastern European urban environment

Characterization of human induced pluripotent stems cells: Current approaches, challenges, and future solutions

Antibacterial effect of a gingival patch containing nano-emulsion of red dragon fruit peel extract on Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Fusobacterium nucleatum assessed in vitro

The most common bacteria causing periodontitis were Porphyromonas gingivalis, Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans . At present, plants are considered a valuable source of natural materials for use in the development of antimicrobial, anti-inflammatory and antioxidant agents. Hylocereus plyrhizus or red dragon fruit peel extract (RDFPE) contains terpenoids, and flavonoids can be an alternative. The gingival patch (GP) has been designed to ensure drug delivery and absorption into tissue targets.

The assessment of Twitter discourse on the new COVID-19 variant, XBB.1.5, through social network analysis

Optimal utilization of groundwater resources and artificial recharge system of Shahriar plain aquifer, Iran

Electrochemical sensors for simultaneous detection of dopamine and uric acid based on a composite of electrochemically reduced graphene oxide and PEDOT:PSS-modified glassy carbon electrode

The Effect of Dry Extraction Process Technology on Characteristics of Porang Flour

Adaptation and mitigation management of drought, wildfire, and climate change toward the development of natural tourism in Jatirejo District, Mojokerto Regency, Indonesia