Is the even distribution of insecticide-treated cattle essential for tsetse control? Modelling the impact of baits in heterogeneous environments

Background: Eliminating Rhodesian sleeping sickness, the zoonotic form of Human African Trypanosomiasis, can be achieved only through interventions against the vectors, species of tsetse (Glossina). The use of insecticide-treated cattle is the most cost-effective method of controlling tsetse but its impact might be compromised by the patchy distribution of livestock. A deterministic simulation model was used to analyse the effects of spatial heterogeneities in habitat and baits (insecticide-treated cattle and targets) on the distribution and abundance of tsetse. Methodology/Principal Findings: The simulated area comprised an operational block extending 32 km from an area of good habitat from which tsetse might invade. Within the operational block, habitat comprised good areas mixed with poor ones where survival probabilities and population densities were lower. In good habitat, the natural daily mortalities of adults averaged 6.14% for males and 3.07% for females; the population grew 8.46in a year following a 90% reduction in densities of adults and pupae, but expired when the population density of males was reduced to <0.1/km2; daily movement of adults averaged 249 m for males and 367 m for females. Baits were placed throughout the operational area, or patchily to simulate uneven distributions of cattle and targets. Gaps of 2–3 km between baits were inconsequential provided the average imposed mortality per km2 across the entire operational area was maintained. Leaving gaps 5–7 km wide inside an area where baits killed 10% per day delayed effective control by 4–11 years. Corrective measures that put a few baits within the gaps were more effective than deploying extra baits on the edges. Conclusions/Significance: The uneven distribution of cattle within settled areas is unlikely to compromise the impact of insecticide-treated cattle on tsetse. However, where areas of >3 km wide are cattle-free then insecticide-treated targets should be deployed to compensate for the lack of cattle

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A Comparison of Analog and Direct Digital Control (DDC) of a Physical Process

The following report presents the development of a computer-based system designed to examine the response of a physical process is a process trainer, PT326, from Feedback Corporation. There are two main categories of control available to the user: (1) analog control and (2) digital control. Within each of these categories the following types of control systems are available: (1) Proportional control, (2) Proportional-Integral control, (3) Proportional-Integral-Derivative control and (4) On-Off control. The user can examine both regulator and servo response for any of the given control systems. All parameters associated with the selected control system are variable and user-input. The software is designed to be user-friendly. The user examines the response of the process to different control systems through the use of full-screen, high-resolution, color graphs. These graphs are linear and labeled. There are two main categories of graphs available to the user: (1) real-time monitoring and (2) graphs with labeled time base. Within each category there are four different graphs available. These graphs are available under any given control system. The user may also obtain hardcopy of these graphs

Commerical Vehicle Enforcement using License Plate Recognition Technology

Speed limits for large trucks have been reduced at many locales for air quality and safety reasons. To realize an improvement in air quality and safety, however, diligent enforcement and fitting punishment have to be implemented. This may put a strain on already tight resources and manpower for state and local agencies. To this end, this paper presents a license plate recognition (LPR) technology based heavy vehicle speed enforcement system that requires relatively minimal initial investment and no increase in enforcement personnel, cruisers, or pursue/pull-over activities. The efficiency of the system is achieved by catching speeding trucks in the act and then enforcing the law at weigh stations, which all trucks, with few exceptions, are required to enter. The configuration of the system for the Knoxville, TN study site is presented. Strategic placement of LPR units on I-40 and I-75 enables the speed tracking and enforcement process. Identified trucks are checked against the CVEIW national database for additional inspection, enforcement, and citation activities

Participating in the Frankfurt Book Fair

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Hargrove, John R.

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Hargrove, Joseph

Co A. 1319 Engr. GS Regt. Camp Sutton, N.C.https://dh.howard.edu/prom_members/1036/thumbnail.jp

Cutaneous Electrode Positioning

A device and method for positioning a cutaneous electrode for delivery of electrical stimulation to a subject\u27s head. A harness is worn on a subject\u27s head with a first band of the harness worn in a closed loop around the subject\u27s head and around a desired contact location on the subject\u27s head. A tensioning strap of the harness is worn across the desired contact location and connected at spaced-apart attachment locations of the strap to spaced-apart attachment locations of the harness such that an electrode disposed over the desired contact location on the subject\u27s head is held in place by the tensioning strap