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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.

Abstract Background To describe the demographic and geographic distribution of tuberculosis (TB) in Manitoba, thus determining risk factors associated with clustering and higher incidence rates in distinct subpopulations. Methods Data from the Manitoba TB Registry was compiled to generate a database on 855 patients with tuberculosis and their contacts from 1992–1999. Recovered isolates of M. tuberculosis were typed by IS6110 restriction fragment length polymorphisms. Bivariate and multivariate logistic regression models were used to identify risk factors involved in clustering. Results A trend to clustering was observed among the Canadian-born treaty Aboriginal subgroup in contrast to the foreign-born. The dominant type, designated fingerprint type 1, accounts for 25.8% of total cases and 75.3% of treaty Aboriginal cases. Among type 1 patients residing in urban areas, 98.9% lived in Winnipeg. In rural areas, 92.8% lived on Aboriginal reserves. Statistical models revealed that significant risk factors for acquiring clustered tuberculosis are gender, age, ethnic origin and residence. Those at increased risk are: males (p < 0.05); those under age 65 (p < 0.01 for each age subgroup); treaty Aboriginals (p < 0.001), and those living on reserve land (p < 0.001). Conclusion Molecular typing of isolates in conjunction with contact tracing data supports the notion of the largest ongoing transmission of a single strain of TB within the treaty-status population of Canada recorded to date. This data demonstrates the necessity of continued surveillance of countries with low prevalence of the disease in order to determine and target high-risk populations for concentrated prevention and control measures.

Abstract Background Tuberculosis (TB) surveillance programs in Canada have established that TB in Canada is becoming a disease of geographically and demographically distinct groups. In 1995, treaty status aboriginals from the province of Manitoba accounted for 46% of the disease burden of this sub-group in Canada. The TB incidence rates are dramatically high in certain reserves of Manitoba and are equivalent to rates in African countries. The objective of our study was to identify prevalent isolates of Mycobacterium tuberculosis in the patient population of Manitoba using molecular epidemiology tools, studying the patient demographics associated with the prevalent strain and studying the in vitro cytokine profiles post-infection with the predominant strain. Methods Molecular typing was performed on all isolates available between 1992 to1997. A clinical database was generated using patient information from Manitoba. THP-1 cells were infected using strains of M. tuberculosis and cytokine profiles were determined using immunoassays for cytokines IL-1β, IL-10, IL-12, IFN-γ and TNF-α. Results In Manitoba, 24% of the disease burden is due to a particular M. tuberculosis strain (Type1). The strain is common in patients of aboriginal decent and is responsible for at least 87% of these cases. Cytokine assays indicate that the Type1 strain induces comparatively lower titers of IL-1β, IFN-γ and TNF-α in infected THP-1 cells as compared to H37Ra and H37Rv strains. Conclusion In Manitoba, Type1 strain is predominant in TB patients. The majority of the cases infected with this particular strain are newly active with a high incidence of respiratory disease, positive chest radiographs and pulmonary cavities. In vitro secretion of IL-1β, IFN-γ and TNF-α is suppressed in Type1 infected culture samples when compared to H37Ra and H37Rv infected cells.

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]

Abstract The present investigation was carried out to study the effect of LC50 of the entomopathogenic fungi (EPF), Paecilomyces lilacinus and Beauveria bassiana, on larval mortality of the greater wax moth (GWM), Galleria mellonella L., under laboratory conditions and also to study the effect of different doses of gamma irradiation (70, 100, 125, and 150 Gy), separately or combined with the LC50 of the isolates of the EPF, B. bassiana, and P. lilacinus, on the second-instar larvae of G. mellonella larval mortality. The combined treatment of gamma irradiation and EPF increased the larval mortality rates than that at each treatment alone. The highest percentage of larval mortality was 78 and 84%, with 125 Gy + B. bassiana in the case of F1 male and F1 female, respectively. According to the obtained results, the gamma irradiation increased the pathogenicity of the fungi against the tested larvae. The combination between the two control tools may provide satisfactory control of the insect-pest, especially, in the storage.

The main objective of e-learning systems is to improve the student- learning performance and satisfaction. This can be achieved by providing a personalized learning experience that identifies and satisfies the individual learner's requirements and abilities. The performance of the e-learning systems can be significantly improved by exploiting dynamic selflearning capabilities that rapidly adapts to prior user interactions within the system and the continuous changes in the environment. In this paper, a dynamic multi-agent system using particle swarm optimization (DMAPSO) for e-learning systems is proposed. The system incorporates five agents that take into consideration the variations in the capabilities among the different users. First, the Project Clustering Agent (PCA) is used to cluster a set of learning resources/projects into similar groups. Second, the Student Clustering Agent (SCA) groups students according to their preferences and abilities. Third, the Student-Project Matching Agent (SPMA) is used to map each learner's group to a suitable project or particular learning resources according to specific design criteria. Fourth, the Student-Student Matching Agent (SSMA) is designed to perform the efficient mapping between different students. Finally, the Dynamic Student Clustering Agent (DSCA) is employed to continually tracks and analyzes the student's behavior within the system such as changes in knowledge and skill levels. Consequently, the DSCA adapts the e-learning environments to accommodate these variations. Experimental results demonstrate the effectiveness of the proposed system in providing near-optimal solutions in considerably less computational time.

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.

Tuberculosis (TB) is a potentially fatal disease spread by an airborne pathogen infecting approximately one third of the globe. For decades, contact tracing (CT) has served a key role in the control of TB and many other notifiable communicable diseases. Unfortunately, CT is a labor-intensive and time-consuming process and is often conducted by a small and overworked nursing staff. To help improve the effectiveness of CT, we introduce a detailed, individual-based model of CT for the Canadian province of Saskatchewan. The model captures the detailed operation of TB CT, including loss to follow-up, and prophylactic and case treatment. This representation is used to assess the impact on active TB cases and TB infection prevalence of differential scoping, speed, prioritization of the CT process, and reduced loss to follow-up. Scenario results are broadly consistent with--but provide many additional insights beyond--our previously reported findings using an aggregate model. In the context of a stylized northern community, findings suggest that age- and ethnicity-prioritized schemes could improve CT effectiveness compared to unprioritized schemes by dramatically reducing TB infection and preventing on average roughly 11% ("p" < .0001) of active TB cases over a period of 20 years. Reducing loss to follow-up to 10% could yield 5.4% ("p" = .02) TB cases prevented on average with lower prevalence of TB infection, but improving the CT speed does not yield significant improvement in TB outcomes. Finally, although the work emphasized the value of social network analysis, we found that caution should be exercised in directly translating social network analysis-observed associations into prioritization recommendations.

Pulmonary hypertension (PH) in the Intensive Care Unit (ICU) may be due to preexisting pulmonary vascular lung disease, liver disease, or cardiac diseases. PH also may be caused by critical illnesses, such as acute respiratory distress syndrome (ARDS), acute left ventricular dysfunction and pulmonary embolism, or may occur after cardiac or thoracic surgery. Regardless of the underlying cause of PH, the final common pathway for hemodynamic deterioration and death is RV failure, which is the most challenging aspect of patient management. Therapy is thus aimed at acutely relieving RV overload by decreasing PVR and reversing RV failure with pulmonary vasodilators and inotropes.

Nasogastric tube has a key role in the management of substantial number of hospitalized patients particularly the critically ill. In spite of the apparent simple insertion technique, nasogastric tube placement has its serious perhaps fatal complications which need to be carefully assessed. Pulmonary misplacement and associated complications are commonplace during nasogastric tube procedure. We present a case of tension pneumothorax and massive surgical emphysema in critically ill ventilated patient due to inadvertent nasogastric tube insertion and also discussed the risk factors, complication list, and arrays of techniques for safer tube placement.

Pulmonary embolism (PE) is a common cause of morbidity and mortality in hospitalized patients. Malignancy, prolonged recumbence, and chemotherapy are renowned risk factors for development of clinically significant PE. Cancer exerts a multitude of pathophysiological processes, for example, hypercoagulability and abnormal vessels with sluggish circulation that can lead to PE. One of the peculiar characteristics of tumor cells is their ability to reach the circulation and behave as blood clot—not a metastasis-occluding the pulmonary circulation. We present a case of fatal pulmonary embolism diagnosed histologically to be due to tumor cell embolism.