Development and Validation of a Hybrid Virtual/Physical Nuss Procedure Surgical Trainer

With continuous advancements and adoption of minimally invasive surgery, proficiency with nontrivial surgical skills involved is becoming a greater concern. Consequently, the use of surgical simulation has been increasingly embraced by many for training and skill transfer purposes. Some systems utilize haptic feedback within a high-fidelity anatomically-correct virtual environment whereas others use manikins, synthetic components, or box trainers to mimic primary components of a corresponding procedure. Surgical simulation development for some minimally invasive procedures is still, however, suboptimal or otherwise embryonic. This is true for the Nuss procedure, which is a minimally invasive surgery for correcting pectus excavatum (PE) – a congenital chest wall deformity. This work aims to address this gap by exploring the challenges of developing both a purely virtual and a purely physical simulation platform of the Nuss procedure and their implications in a training context. This work then describes the development of a hybrid mixed-reality system that integrates virtual and physical constituents as well as an augmentation of the haptic interface, to carry out a reproduction of the primary steps of the Nuss procedure and satisfy clinically relevant prerequisites for its training platform. Furthermore, this work carries out a user study to investigate the system’s face, content, and construct validity to establish its faithfulness as a training platform

Simulation Modeling and Analysis of Complex Port Operations with Multimodal Transportation

AbstractWorld trade has been increasing dramatically in the past two decades, and as a result containers exchange has grown significantly. Accordingly, container terminals are expanding to meet this increase and new container ports have opened. Ports with one or more container terminals are considered complex systems in which many resources, entities and transporters interact to achieve the objective of safely moving containers delivered by ships inland as well as loading containers delivered by trucks and rail onto ships. Ports with multimodal transportation systems are in particular complex as they typically operate with ships arriving to one or more terminals, multiple quay cranes, rubber tyred gantry cranes, trains, and trucks delivering containers of different types to terminals.With several resources of different types working and interacting, the system can be so complex that it is not easy to predict the behavior of the system and its performance metrics without the use of simulation. In this paper, a generic discrete-event simulation that models port operations with different resource types including security gates, space, rubber tyred gantry cranes, trains, quay cranes, and arriving and departing ships, trucks, and trains is presented. The analysis will entail studying various scenarios motivated by changes in different inputs to measure their impact on the outputs that include throughput, resource utilization and waiting times

NEOPTERIN AND INTERFERON-GAMMA AS IMMUNE RESPONSE MARKERS IN BETATHALASSEMIA MAJOR PATIENTS

Objective: The assessment of neopterin and interferon-gamma (IFN-γ) levels as a part of immune system response about serum iron status in β-thalassemia (TM) major patients.Methods: Spectrophotometry applied for the estimation of iron status including serum iron level, total iron-binding capacity, and unsaturated iron-binding capacity. Enzyme-linked immunosorbent assay (ELISA) applied for the estimation of the serum cytokines included neopterin and IFN-γ also serum ferritin estimation by ELISA from 130 β-TM major patients where they divided according to serum ferritin level (< and ≥2500 ng/mL).Results: The neopterin and IFN-γ concentration showed significantly increased with direct correlation among TM patient group when compared to the normal healthy control group. However, there was no significant difference between different levels of serum ferritin.Conclusion: The increased serum level of neopterin and IFN-γ found in patients with β-TM may be due to the direct effect of iron on cellular immune cells beside of immune system response to the effect of iron toxicity on different body organs. There was a direct moderate relationship between neopterin and IFN-γ

A new CP-approach for a parallel machine scheduling problem with time constraints on machine qualifications

International audienceThis paper considers the scheduling of job families on parallel machines with time constraints on machine qualifications. In this problem, each job belongs to a family and a family can only be executed on a subset of qualified machines. In addition, machines can lose their qualifications during the schedule. Indeed, if no job of a family is scheduled on a machine during a given amount of time, the machine loses its qualification for this family. The goal is to minimize the sum of job completion times, i.e. the flow time, while maximizing the number of qualifications at the end of the schedule. The paper presents a new Constraint Programming (CP) model taking more advantages of the CP feature to model machine disqualifications. This model is compared with two existing models: an Integer Linear Programming (ILP) model and a Constraint Programming model. The experiments show that the new CP model outperforms the other model when the priority is given to the number of disqualifications objective. Furthermore, it is competitive with the other model when the flow time objective is prioritized

Adsorption Sulfate from Wastewater by Using New Material

Using physical activation, a new composite adsorbent was prepared by modifying low-cost local adsorbent. This low-cost local adsorbent was also prepared from activating sludge, bentonite, and limestone (SBL). In comparison to the low-cost LCL, the adsorption capacity of the new composite adsorbent was improved. This was measured in terms of its ability to remove sulfate from wastewater. The behavior of the sulfate adsorption processes by using (SBL) as an adsorbent was investigated in batch experiments by examining different values of solution pH, contact time, adsorbent dose, and initial SO4 concentration. The high removal efficiency was exhibited by (SBL) = 96%. These results reveal the great potential of the new composite adsorbent (SBL) if applied to the absorption of sulfate ions

Artificial Intelligence: Serving American Security and Chinese Ambitions

In recent years artificial intelligence has entered a new era, which gives rise to many hopes for powerful states such as the United States and China. In this paper, we analyze the importance and role of artificial intelligence in technological development in each of the two countries on the one hand, and its influence on China-American relations in terms of technological and geopolitical conflict

The Kynurenine Pathway Is Upregulated by Methyl-deficient Diet and Changes Are Averted by Probiotics

Scope Probiotics exert immunomodulatory effects and may influence tryptophan metabolism in the host. Deficiency of nutrients related to C1 metabolism might stimulate inflammation by enhancing the kynurenine pathway. This study used Sprague Dawley rats to investigate whether a methyl‐deficient diet (MDD) may influence tryptophan/kynurenine pathways and cytokines and whether probiotics can mitigate these effects. Methods and Results Rats are fed a control or MDD diet. Animals on the MDD diet received vehicle, probiotics (L. helveticus R0052 and B. longum R0175), choline, or probiotics + choline for 10 weeks (n = 10 per group). Concentrations of plasma kynurenine metabolites and the methylation and inflammatory markers in plasma and liver are measured. Results MDD animals (vs controls) show upregulation of plasma kynurenine, kynurenic acid, xanthurenic acid, 3‐hydroxyxanthranilic acid, quinolinic acid, nicotinic acid, and nicotinamide (all p < 0.05). In the MDD rats, the probiotics (vs vehicle) cause lower anthranilic acid and a trend towards lower kynurenic acid and picolinic acid. Compared to probiotics alone, probiotics + choline is associated with a reduced enrichment of the bacterial strains in cecum. The interventions have no effect on inflammatory markers. Conclusions Probiotics counterbalance the effect of MDD diet and downregulate downstream metabolites of the kynurenine pathway