Effect of dynamic coupling in an inferior olive neuron model and synchronization

In this paper, we use the idea of dynamic coupling to describe the effect of drugs or chemical substances on the electrophysiological properties of the inferior olive neuron (ION). Therefore, a six-dimensional dynamically coupled Kazantsev master–slave configuration of the ION is obtained. In this configuration, the master and slave subsystems have an indirect interaction, and they are not connected through common signals; instead, the slave subsystem receives a coupling signal, which is dynamically generated by a second order linear system. This type of coupling is called dynamic coupling and enables us to take into consideration the state of the medium through which the master and slave are interconnected. The dynamical behavior of the new model is analyzed analytically using limit cycle prediction and numerically via the two-dimensional bifurcation diagrams with respect to two essential bifurcation parameters of the model. Taking the nonlinear function parameter a and two parameters from the coupling subsystem, the adaptive coupling parameter γ2 and the master–slave coupling strength b, as essential bifurcation parameters, the results show that a change of one of these parameters gives rise to complex dynamics such as periodic oscillations, period doubling scenarios, and chaotic states characterized by spike-bursting. Assuming two coupled neurons with parameter mismatch, it is observed that an increase in the external coupling strength ɛ1 favors their synchronization. Furthermore, the analog circuit of the complete new model confirms the burst analysis and the existence of chaos in the model

Exploring the knowledge and attitudes of Cameroonian medical students towards global surgery: A web-based survey.

INTRODUCTION:Global surgery is a growing field studying the determinants of safe and affordable surgical care and advocating to gain the global health community's attention. In Cameroon, little is known about the level of knowledge and attitudes of students. Our survey aimed to describe the knowledge and attitudes of Cameroonian medical students towards global surgery. MATERIALS AND METHODS:We performed an anonymous online survey of final-year Cameroonian medical students. Mann-Whitney U test and Spearman correlation analysis were used for bivariate analysis, and the alpha value was set at 0.05. Odds ratios and their 95% confidence intervals were calculated. RESULTS:204 respondents with a mean age of 24.7 years (±2.0) participated in this study. 58.3% were male, 41.6% had previously heard or read about global surgery, 36.3% had taken part in a global surgery study, and 10.8% had attended a global surgery event. Mercy Ships was well known (46.5%), and most students believed that surgical interventions were more costly than medical treatments (75.0%). The mean score of the global surgery evaluation was 47.4% (±29.6%), and being able to recognize more global surgery organizations was correlated with having assumed multiple roles during global surgery studies (p = 0.008) and identifying more global surgery indicators (p = 0.04). Workforce, infrastructure, and funding were highlighted as the top priorities for the development of global surgery in Cameroon. CONCLUSION:Medical students are conscious of the importance of surgical care. They lack the opportunities to nurture their interest and should be taught global surgery concepts and skills

Theoretical analysis of spatial nonhomogeneous patterns of entomopathogenic fungi growth on insect pest

This paper presents the study of the dynamics of intrahost (insect pests)-pathogen [entomopathogenic fungi (EPF)] interactions. The interaction between the resources from the insect pest and the mycelia of EPF is represented by the Holling and Powell type II functional responses. Because the EPF’s growth is related to the instability of the steady state solution of our system, particular attention is given to the stability analysis of this steady state. Initially, the stability of the steady state is investigated without taking into account diffusion and by considering the behavior of the system around its equilibrium states. In addition, considering small perturbation of the stable singular point due to nonlinear diffusion, the conditions for Turing instability occurrence are deduced. It is observed that the absence of the regeneration feature of insect resources prevents the occurrence of such phenomena. The long time evolution of our system enables us to observe both spot and stripe patterns. Moreover, when the diffusion of mycelia is slightly modulated by a weak periodic perturbation, the Floquet theory and numerical simulations allow us to derive the conditions in which diffusion driven instabilities can occur. The relevance of the obtained results is further discussed in the perspective of biological insect pest control

The Implications of Global Neurosurgery for Low- and Middle-income Countries: The Case of Cameroon

The unequal distribution of neurosurgical resources and diseases in the world contributes to inequality. Eight in 10 neurosurgical cases needing essential neurosurgical care are found in Low- and Middle-Income Countries (LMICs); however, LMICs lack the neurosurgical resources to address these needs. Besides, where neurosurgical care is available, it is not financially accessible to the majority of patients. Global Neurosurgery is a rapidly growing field that places a priority on improving health outcomes and achieving health equity for all people affected by neurosurgical conditions. To achieve safe, accessible, and affordable neurosurgical care for all, LMIC neurosurgeons should participate in national and international global neurosurgical activities, develop disruptive solutions to local problems and work with local stakeholders to address global neurosurgery problems.</jats:p

Production performance, egg quality characteristics and serum biochemical parameters on Brahma laying hens (Gallus gallus domesticus) fed with supplemented Chromolaena odorata leaf meal

An experiment was conducted to evaluate the effect of graded levels of Chromolaena odorata leaf meal (COLM) on production performance, egg quality characteristics, and serum biochemical parameters on Brahma laying hens. A total of forty-five local laying hens aged 4 to 5 months were weighed and assigned to three treatment groups in a completely randomized design. COLM was used as a supplement and incorporated into the diets at 0, 1, and 2% in diets T0, T1, and T2 respectively. Data were collected on production performance, egg quality characteristics, and serum biochemistry. Results from the study indicate that body weight gain, average weight, and egg volume were low (p&lt;0.05) with treatment T2 compared to control (T0) and the best was obtained with treatment T1. The Haugh unit and percentage hen day production were not negatively affected by the treatment levels of COLM. There were significant (p&lt;0.05) differences in triglyceride, total cholesterol, and urea. Results obtained from this study revealed that the inclusion of 1% of COLM improved the egg quality as well as the health status of the birds without having any detrimental effect on the birds.</jats:p

Establishment of a Brain Tumor Consortium of Africa: Advancing Collaborative Research and Advocacy for Brain Tumors in Africa

Background: Brain tumors represent a significant global health challenge, with rising incidence and mortality impacting individuals worldwide and contributing to cancer-related morbidity and mortality. In Africa, this burden is exacerbated by limited access to advanced diagnostics, treatment options, and multidisciplinary care, compounded by the absence of standardized cancer registration and tumor biobanking. The introduction of molecular diagnostics, as outlined in the 2021 World Health Organization central nervous system (CNS) tumor classification, adds complexity to brain tumor management, particularly in regions with scarce resources. Methods: To address these issues, the Brain Tumor Consortium for Africa (BTCA) was established in 2023, bringing together experts to improve CNS tumor diagnosis, patient care, and research. The initial project, conducted via an electronic questionnaire, aimed to assess neuro-oncology capacity across Sub-Saharan Africa. Results: The study revealed significant gaps, with a limited number of institutions incorporating molecular subtyping into their diagnostic algorithms. The consortium\u27s efforts focus on enhancing local data use, informing public policy, and promoting collaboration to advance neuro-oncology practices in Africa. By fostering a network enlisting the expertise of collaborators in the fields of neurosurgery, neurology, neuropathology, anatomic pathology, and medical and radiation oncology, the BTCA seeks to improve brain tumor management through better diagnostics, infrastructure, and policy advocacy. Future directions include expanding molecular diagnostic capabilities, standardizing brain tumor biobanking, enhancing data collection, and advocating for improved brain tumor care in national health agendas. Conclusions: The BTCA represents a pioneering model of collaboration and innovation in addressing the unique challenges of brain tumor care in Africa