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An air-entraining vortex begins to form when the submergence of an intake is not adequate and less than the critical value known as critical submergence. In the present study, critical submergence for a laterally placed single rectangular intake under a uniform approach flow in an open channel was investigated experimentally. Analysis of the data collected in the present study reveals that critical submergence is significantly influenced by intake size, intake aspect ratios, approach Froude number, intake Froude number, intake Reynolds number, and Weber number. However, intake Froude number and intake aspect ratio were found to be the most sensitive parameters that affect critical submergence. An empirical relationship for critical submergence has been developed using collected data used to compute the critical submergence within an error of ±20%. The findings of this investigation is advantageous for hydraulic engineers when designing lateral rectangular intakes to prevent the formation of an air-entraining vortex. Practical Applications: Insufficient water cover over the hydraulic intakes causes an air-entraining vortex formation in the vicinity of the intake. The formation of such an air-entraining vortex results in significant hydraulic issues, structural damages, etc. Ensuring enough submergence for the intake during its operational period is necessary to evade such problems. The submergence at which the air-core tail of the surface vortex reaches the intake initiating air-entrainment is called critical submergence. Critical submergence is an important parameter for the design of intakes and is widely used as a parameter to determine an incipient state for which no air is entrained by intake vortices. This paper discusses the experimental investigation of critical submergence for single lateral rectangular intakes concerning significant geometrical parameters, such as intake aspect ratio, approach Froude number, intake Froude number, etc. The proposed empirical equations in this study are helpful to hydraulic engineers when computing critical submergence to fix the invert level of a lateral rectangular intake. [ABSTRACT FROM AUTHOR]

Background and Aims: Crimean‐Congo Hemorrhagic Fever (CCHF) is a significant public health concern transmitted by ticks. This study seeks to thoroughly grasp the epidemiology and transmission patterns of CCHF, which is caused by the CCHF virus (CCHFV), a member of the Nairovirus genus in the Bunyaviridae family. Methods: The study investigates the global distribution and endemicity of CCHF, its mortality rates, modes of transmission (including tick bites, contact with infected animal blood, and limited person‐to‐person transmission), and factors influencing its prevalence across different regions. Genetic diversity within CCHFV and its impact on transmission dynamics are explored, along with efforts to control the disease through tick prevention, antiviral treatment, and the development of vaccines and diagnostics. Results: CCHFV exhibits widespread distribution, particularly in the Middle East, Africa, Asia, and Eastern Europe, with an overall mortality rate of approximately 30% and a case fatality rate ranging from 10% to 40%. Transmission occurs primarily through tick bites and contact with infected animal blood, with limited person‐to‐person transmission. Livestock workers, slaughterhouse employees, and animal herders in endemic areas are most affected by their frequent interaction with sick animals and ticks. Genetic diversity within CCHFV contributes to variations in transmission dynamics, complicating control efforts. Antiviral ribavirin shows efficacy in treating CCHF infection. Conclusion: This study underscores the importance of further research to understand the enzootic environment, transmission routes, and genetic diversity of CCHFV for effective control measures, including the development of vaccines, treatment options, and diagnostics. Highlights: Crimean‐Congo Hemorrhagic Fever (CCHF) is prevalent in the Middle East, Africa, Asia, and Eastern Europe, with a mortality rate of ~30%.Transmission primarily occurs through tick bites and contact with infected animal blood, posing risks to livestock workers and animal herders.Genetic diversity within CCHFV influences its transmission dynamics, complicating control efforts.Antiviral ribavirin demonstrates efficacy in treating CCHF infections, highlighting potential therapeutic avenues. [ABSTRACT FROM AUTHOR]

Lakes are very important for domestic use, commercial purposes, and ecosystem sustenance; nevertheless, studies on how different stressors influence water resources are limited, posing challenges in the planning and managing of water resources. Lake Babati is one of the important lakes in the East African rift valley as a source of fish, drinking water, and hippopotamus habitat. The lake level has consistently declined, threatening the life of organisms depending on the lake. Nevertheless, no study postulated the reasons for its decline. Therefore, this study used statistical methods, regression analysis and HEC-HMS hydrological model to investigate the association and sensitivity of the hydrological components driving the lake level variability. Results showed that the Lake Babati level was significantly declining (p < 0.01) at a rate of 0.025 m yearly. The lake level variability was most sensitive to inflow, while outflow and evaporation had almost equivalent magnitude in driving the lake level variability and direct rainfall had the least influence. Although the lake level variability corresponded to changes in the basin supply components, the declining lake level trend was neither directly related to lake evaporation nor inflow as both parameters showed no significant trends. Furthermore, groundwater abstraction within the lakeshore is smaller than lake evaporation and is unlikely the main driver of the decline in lake level. Therefore, the declining lake level seemed related to the spillway outflow, which had been improved to avoid lake flooding resulting in large outflow during the peak seasons and probably the reason for the significant decline in the lake levels even in the rainy seasons. This study benchmarked the most sensitive hydrological drivers influencing lake level whose accurate monitoring and management could rescue the situation.