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Compartmental models are widely used in mathematical epidemiology to describe the dynamics of infectious diseases or in mathematical models of population genetics. In this study, we study a time-dependent Susceptible-Infectious-Susceptible (SIS) Partial Differential Equation (PDE) model that is based on a diffusion-drift approximation of a probability density from a well-known discrete-time Markov chain model. This SIS-PDE model is conservative due to the degeneracy of the diffusion term at the origin. The main results of this article are the qualitative behavior of weak solutions, the dependence of the local asymptotic property of these solutions on initial data, and the existence of Dirac delta function type solutions. Moreover, we study the long-term behavior of solutions and confirm our analysis with numerical computations.

Objective: To determine how Thymus vulgaris and Ecalyptus globulus affected the symptoms of coronavirus disease- 2019 patients. Method: The experimental case-control study was conducted in Al-Nasiriya city, Iraq, from December 15, 2020, to February 20, 2021, and comprised patients of either gender aged 20-50 years diagnosed with coronavirus disease- 2019 infection. The patients’ symptoms ranged from mild to severe. Half of the sample was exposed to the study’s treatment protocol, while the other half acted as control. Thyme, orange and lemon were employed as sources of vitamin C, as well as eucalyptus leaves and oil. The cases were exposed to eucalyptus vapours for 5-10 minutes after thoroughly washing the plant leaves (7-10 leaves or 5 drops of oil) and boiling them in drinking water at 100°C for 10- 15 minutes. Data was analysed using SPSS 23. Results: Of the 48 patients, 24(50%) were in each of the two groups. Age and gender were not significantly different (p>0.05), while body mass index and blood group distribution was significantly different between the groups (p0.05). Conclusion: Using eucalyptus vapours in the form of dried leaves or oil could significantly lessen coronavirus disease- 2019 symptoms. Keywords: Eucalyptus, Thymus, Plant, Citrus, Cough, Smell, COVID-19, Leaves, Vaccines, Vitamins.

Background: Depression and anxiety are among the underlying factors and effects of heart attack. Reducing these patients' levels of depression and anxiety is crucial for reducing recurrent strokes and enhancing their quality of life (QOL). The current study was conducted to examine the effect of cognitive behavioral therapy (CBT) on depression and anxiety in heart attack patients. Methods: The current experimental study was conducted on a community of heart attack patients in 2021. The statistical population consisted of 197 patients admitted to the CCU of Yarmouk Teaching Hospital and Baghdad Teaching Hospital, Iraq. Using a simple random sampling method, 84 patients were chosen and divided into experimental and control groups (42 patients in each group). For data collection, the Symptom Checklist-90-Revised (SCL-90-R) was utilized. The data were analyzed using the analysis of covariance (ANCOVA) in SPSS software. The significance level was considered to be equal to 0.05. Results: The mean depression score in the control group (1.27 ± 0.52) was significantly higher after the intervention compared to the experimental group (0.68 ± 0.29) (P < 0.001). In addition, the experimental group's depression score in the posttest stage was significantly lower than in the pretest stage (P < 0.001). ANCOVA showed a statistically significant difference in the mean posttest score of the dependent variables of depression (F = 129.48; P < 0.001) and anxiety (F = 123.99; P < 0.001) in heart attack patients who received the intervention. Conclusion: CBT intervention was impressive in the treatment of anxiety and depression in heart attack patients, resulting in a significant decrease in anxiety and depression and a reduction in the likelihood of future heart attacks. [ABSTRACT FROM AUTHOR]

Patients with heart failure with reduced ejection fraction (HFrEF) have exaggerated sympathoexcitation and impaired peripheral vascular conductance. Evidence demonstrating consequent impaired functional sympatholysis is limited in HFrEF. This study aimed to determine the magnitude of reduced limb vascular conductance during sympathoexcitation and whether functional sympatholysis would abolish such reductions in HFrEF. Twenty patients with HFrEF and 22 age-matched controls performed the cold pressor test (CPT) [left foot 2-min in −0.5 (1)°C water] alone and with right handgrip exercise (EX + CPT). Right forearm vascular conductance (FVC), forearm blood flow (FBF), and mean arterial pressure (MAP) were measured. Patients with HFrEF had greater decreases in %ΔFVC and %ΔFBF during CPT (both P < 0.0001) but not EX + CPT (P = 0.449, P = 0.199) compared with controls, respectively. %ΔFVC and %ΔFBF decreased from CPT to EX + CPT in patients with HFrEF (both P < 0.0001) and controls (P = 0.018, P = 0.015), respectively. MAP increased during CPT and EX + CPT in both groups (all P < 0.0001). MAP was greater in controls than in patients with HFrEF during EX + CPT (P = 0.025) but not CPT (P = 0.209). In conclusion, acute sympathoexcitation caused exaggerated peripheral vasoconstriction and reduced peripheral blood flow in patients with HFrEF. Handgrip exercise abolished sympathoexcitatory-mediated peripheral vasoconstriction and normalized peripheral blood flow in patients with HFrEF. These novel data reveal intact functional sympatholysis in the upper limb and suggest that exercise-mediated, local control of blood flow is preserved when cardiac limitations that are cardinal to HFrEF are evaded with dynamic handgrip exercise. NEW & NOTEWORTHY: Patients with HFrEF demonstrate impaired peripheral blood flow regulation, evidenced by heightened peripheral vasoconstriction that reduces limb blood flow in response to physiological sympathoexcitation (cold pressor test). Despite evidence of exaggerated sympathetic vasoconstriction, patients with HFrEF demonstrate a normal hyperemic response to moderate-intensity handgrip exercise. Most importantly, acute, simultaneous handgrip exercise restores normal limb vasomotor control and vascular conductance during acute sympathoexcitation (cold pressor test), suggesting intact functional sympatholysis in patients with HFrEF. [ABSTRACT FROM AUTHOR]

Compartmental models are widely used in mathematical epidemiology to describe the dynamics of infectious diseases or in mathematical models of population genetics. In this study, we study a time-dependent Susceptible-Infectious-Susceptible (SIS) Partial Differential Equation (PDE)model that is based on a diffusion-drift approximation of a probability density from a well-known discrete-time Markov chain model. This SIS-PDE model is conservative due to the degeneracy of the diffusion term at the origin. The main results of this article are the qualitative behavior of weak solutions, the dependence of the local asymptotic property of these solutions on initial data, and the existence of Dirac delta function type solutions. Moreover, we study the long-term behavior of solutions and confirm our analysis with numerical computations. [ABSTRACT FROM AUTHOR]

Tensegrity structures are spatial structures made up of an assembly of pin-jointed, prestressed continuous tension members and discontinuous compressive members, arranged in different complex shapes. Limited research has been carried out to analyse the dynamic response of these structures under seismic loading. This paper presents a parametric study to identify the suitability of different forms of these structures under combined vertical gravity and lateral seismic loadings. Different tensegrity shapes were analysed, as simplex and complex structures, under wind and earthquake loadings. These responses of the structures were also compared to that of conventional steel structures of the same shapes. Different parameters such as the effect of varying bar diameter, bar thickness, cable diameter, and tower height, were studied, and behavioural trends were identified. It was found that if a suitable tensegrity shape is chosen and optimized, its behavioural trends can be very similar to that of the conventional steel structures, while saving materials and therefore cost. Modal frequencies of the structure were also identified and found to be low, which is beneficial under earthquake loading. Thus, these systems can prove to be a valuable replacement to conventional systems under adverse dynamic loading.