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Giardiasis, caused by the protozoan parasite Giardia intestinalis, poses a significant public health burden worldwide, particularly in regions with limited access to clean water and sanitation infrastructure. Understanding the transmission dynamics of giardiasis and evaluating intervention strategies are crucial for effective disease control. In this study, we apply the theory of optimal control to the giardiasis model. The model includes public health education, treatment, and sanitation as the control measures for giardiasis. The goal is to minimize the infections in the population brought on by interactions with asymptomatic, symptomatic, and contaminated environments while reducing the cost of the control measures. We accomplish this goal by using Pontryagin’s Maximum Principle, where fourth-order Runge–Kutta is used to perform numerical simulations for both forward and backward in-time schemes. We simulate the model under different control scenarios to determine which strategy could produce the greatest results. The results demonstrate that the control strategy combining the three control measures (public health education, treatment, and sanitation) proves to be more effective in curbing the spread of giardiasis. Moreover, the incremental cost-effectiveness ratio (ICER) is used to analyze cost-effectiveness. The cost-effectiveness analysis revealed that the strategy that contains treatment and sanitation is the best strategy to implement in the population in case of budget constraints. Hence, our study recommends that sanitizing the environment and treating the infected individuals immediately could be the best practice for controlling the spread of giardiasis disease on an entire population.

A Mach–Zehnder interferometer (MZI) electro-optic (E-O) switch based on a guest–host material DR1/PC was designed and fabricated. The optical properties and long-term stability of the material were studied. By optimizing the concentration of DR1, the DR1/PC material exhibited an E-O coefficient of 12.8 pm/V at 1310 nm. The characteristic parameters of the waveguide were calculated, and the fabrication process was strictly controlled. The MZI switch on-off time was found to be about 50 ns. The extinction ratio was measured to be about 13.4 dB. At room temperature, the switch could keep operating for at least 150 days.

Regression test case reduction aims at selecting a representative subset from the original test pool, while retaining the largest possible fault detection capability. Cluster analysis has been proposed and applied for selecting an effective test case subset in regression testing. It groups test cases into clusters based on the similarity of historical execution profiles. In previous studies, historical execution profiles are represented as binary or numeric function coverage vectors. The vector-based similarity approaches only consider which functions or statements are covered and the number of times they are executed. However, the vector-based approaches do not take the relations and sequential information between function calls into account. In this paper, we propose cluster analysis of function call sequences to attempt to improve the fault detection effectiveness of regression testing even further. A test is represented as a function call sequence that includes the relations and sequential information between function calls. The distance between function call sequences is measured not only by the Levenshtein distance but also the Euclidean distance. To assess the effectiveness of our approaches, we designed and conducted experimental studies on five subject programs. The experimental results indicate that our approaches are statistically superior to the approaches based on the similarity of vectors (i.e. binary vectors and numeric vectors), random and greedy function-coverage-based maximization test case reduction techniques in terms of fault detection effectiveness. With respective to the cost-effectiveness, cluster analysis of sequences measured using the Euclidean distance is more effective than using the Levenshtein distance.

An optimal control model of African trypanosomiasis to minimize the cost of implementing control efforts and the number of infected humans, cattle, and tsetse-fly populations in their respective communities was formulated. Time-dependent controls such as public health education, human and cattle treatments, and tsetse-fly trapping were considered. Using Pontryagin’s maximum principle, the necessary conditions and the existence of an optimal control solution of an optimal control problem were analyzed. Using forward and backward in time fourth-order Runge–Kutta scheme, numerical simulations of the optimal control problem were performed. The results showed that the strategy involving public health education, treatment of humans, cattle treatment, and trapping of tsetse-flies was the most effective in reducing the number of infected individuals in their respective populations. Furthermore, the incremental cost-effectiveness analysis was performed, which showed that the tsetse-fly trapping was the most cost-effective strategy to implement in source limited settings.

In this study, we propose a deterministic model describing the dynamics of anthrax transmission in animals. It is assumed in the model that anthrax is contracted when susceptible animal comes into contact with infected animals, infected carcasses or the spores of Bacillus anthracis. Conditions for disease-free and endemic equilibria are derived and the basic reproduction number ($R_0$) is computed. The disease-free equilibrium is stable when $R_0<1$ and the disease will be eliminated. If $R_0>1$, the disease persists, therefore, the endemic equilibrium is globally stable. Further, we extend our model by applying optimal control problem in which vaccination for susceptible animals and sanitation are control variables to minimize the anthrax transmission. We study three strategies to investigate the impact of the controls. Our numerical results demonstrate that both vaccination and sanitation help minimizing the transmission although vaccination alone gives more significant impact than sanitation alone. However, the combination of both controls gives the best result in wiping out the anthrax transmission overall. Further, cost-effectiveness analysis shows that the most effective strategy to control anthrax disease is a combination of vaccination and sanitation of the infected areas, therefore these two interventions should be encouraged.

Leptospirosis is a bacteria infection prevalent in many tropical regions, caused by the genus Leptospira. Humans contract the disease by coming in contact with contaminated environments. This study proposes a deterministic mathematical model that links the within-host and between-host dynamics of leptospirosis and investigates its properties. The model’s parameters were estimated by fitting it to real-life data using the “lsqcurvefit” package in MATLAB. The study employs global sensitivity analysis using Latin hypercube sampling with a partial rank correlation coefficient index and uses Pontryagin’s maximum principle to identify cost-effective solutions for time-dependent intervention strategies to suppress the bacteria transmission within a specific period. The results of the study showed that bacteria replication within human and rodent hosts is the major driver of the overall dynamics of leptospirosis and therefore controlling the prevalence of the disease by focusing on the epidemiology components is necessary but will not be effective if the intra-host dynamics of the bacteria within rodent hosts and human hosts are not attentively considered.

Understanding Diabetes

Prediabetes: The Gap between the Onset of Disease and Initiation of Treatment.

Diabetes: A Dietitian’s Perspective.

Use of Modelling for Better Diabetes Care.

No More Highs and Lows with Toujeo®: A New and Improved Insulin Injection.

The cost-effectiveness of wormhole torus-networks is systematically evaluated with emphasis on new buffered-wormhole routing algorithms. These algorithms use fixed datelines and escape channels to alleviate bottleneck and bubble problems caused by previous algorithms so as to improve the buffer efficiency with little hardware overhead. A two-part evaluation environment is developed consisting of a cycle-driven simulator for high-level measurements such as network capacity and an ASIC design package for low-level measurements such as operating frequency and chip area. This environment is used to demonstrate that the new routers are more cost-effective than their counterparts under various workload parameters.

Background: In Japan, where infertility treatment is now covered by insurance, appropriate protocols for patients with diminished ovarian reserve (DOR) based on treatment outcomes and cost-effectiveness must be selected. Therefore, this study aims to provide information on the outcomes and cost-effectiveness of conventional ovarian stimulation and mild stimulation for patients with DOR in Japan.

Methods: Data from 66 women who underwent first oocyte retrieval at Showa University Hospital between May 2019 and November 2023 were analyzed.

Results: The clomiphene citrate (CC) group used significantly fewer gonadotropins and incurred lower costs than the conventional ovarian stimulation group while achieving comparable clinical outcomes, including cumulative live birth rates.

Conclusions: CC-based minimal stimulation is a cost-effective alternative to conventional ovarian stimulation for patients with low ovarian reserve without compromising clinical efficacy. Further randomized controlled trials are required to confirm these findings and optimize protocols for this population.

Allopurinol is an effective urate lowering agent but may lead to rare but life-threatening severe cutaneous adverse reactions (SCAR). Genetic predisposition, age, sex, renal function, dosage and concomitant diuretic use are known risk factors of allopurinol related SCAR. Among these factors, HLA-B${}^{\ast }$58:01 confers the highest risk. Frequency of the HLA-B${}^{\ast }$58:01 allele varies significantly across different ethnic groups. Although the usefulness of HLA-5801 genotyping before initiation of allopurinol has been confirmed by clinical studies, its positive predictive value for SCAR is low because of the low prevalence of HLA-5801 in some localities. Thus, health economic analysis does not consistently show cost-effectiveness of universal screening of HLA-5801 before initiation of allopurinol. However, screening of this genotype in high-risk subjects, including those with renal impairment or advanced age, should be considered on individual basis.

Translational health economics (THE) can be defined as the use of theoretical concepts and empirical methods in health economics to bridge the gap between the decision to fund and use a new health technology in clinical practice (the backend of translational medicine) and the decision to invest into its development (the front end of translational medicine). This chapter provides an overview of this emerging area of research and discusses limitations and research needs.

Theoretical concepts and empirical methods for three aspects of THE are presented: First, to analyze “value” for a potential health technology and to apply or to further develop methods for scrutinizing value propositions related to the decision to initiate a translation process; second, to analyze “uncertainty” and to apply or to further develop methods for generating evidence about a health technology's value early on; and third, to analyze barriers of information and motivation in the cooperative process of translation as well as institutions to overcome these. Rather than the traditional concept where health economic evaluations inform health care decision makers about established technologies with established evidence, THE seeks to integrate the development of innovations, and to provide links to health care business perspectives and decisions.