Colour change in traumatised anterior permanent teeth. A prospective cohort observational study

Background: There is limited information about colour change following traumatic dental injuries (TDI), and any variable associated with discolouration. It is now increasingly recognised that children’s perception and satisfaction are important and may provide an insight into the psychosocial impact of their oral health and their wider quality of life. Therefore, research to quantify colour change with time following TDI and the patient’s perception is important. This study was designed to identify any association between clinical variables and discolouration following TDI. Aim: To investigate the change in colour of permanent teeth following TDI in children. To explore what variables are associated with discolouration. To examine methods of measuring colour change including IKAM system (objective measure), the use of a shade guide (clinical pseudo objective measure), patient’s perception (patient reported measure) and to evaluate the agreement between these three methodologies. Method: Children following TDI were invited to participate in an observational prospective cohort. Colour change was measured using patients’ perception, investigator’s perception (using a shade guide) and an objective digital system (IKAM). Measurements were taken at baseline, 3 months and 6 months following the TDI with IKAM providing objective CIELAB colour scores. Results: Thirty-nine children, with 73 traumatised teeth, completed the study. Twenty-six children attended two follow-up reviews comprising 52 teeth, and thirteen children attended for one follow-up visit only with 21 teeth. A heterogenous sample of TDI was recruited including various types of hard tissue injuries and periodontal injuries with variable pulpal survival and periodontal healing outcomes. At the last review (n=73 teeth) the objective overall colour change was ΔE 5.45 (SD +/- 2.80) with a mean change in ΔL* 0.74 (lighter), Δa* 0.69 (redder) and Δb* 1.73 (yellower). There was little consistency between patients reported colour change and that recorded by the investigator using a shade guide. There was no significant difference in ΔE values as measured by IKAM in comparison with the patients’ or investigator’s perception. Conclusions: Following TDI, there was an observable colour change identified by an objective measure, IKAM. On average, teeth got predominantly yellow and to a lesser extent lighter and redder. Patients and investigator measures were inconsistent when compared to the objective measure (IKAM). No variables were identified to be associated with colour change. However several variables came to significance (p<0.05). These variables were; time interval between the baseline assessment and the final review, presence of hard tissue injury, splinting, and restoration placed at or before baseline

Simultaneous Stabilization Of Power System Using UPFC-Based Controllers

This article studies the use of robust UPFC-based stabilizers to damp low frequency oscillations. The potential of the UPFC-based stabilizers to enhance the dynamic stability is evaluated by singular value decomposition. Particle swarm optimization technique is used to optimize the parameters of each stabilizer, first individually, then concurrently. To ensure the robustness of the proposed stabilizers, the design process considers a wide range of operating conditions. The effectiveness of the proposed controllers is verified through several linear and nonlinear analysis techniques. These techniques prove that the coordinated design of UPFC-based stabilizers is superior over any of the individual designs

Simultaneous Stabilization Of Power System Using UPFC-Based Controllers

This article studies the use of robust UPFC-based stabilizers to damp low frequency oscillations. The potential of the UPFC-based stabilizers to enhance the dynamic stability is evaluated by singular value decomposition. Particle swarm optimization technique is used to optimize the parameters of each stabilizer, first individually, then concurrently. To ensure the robustness of the proposed stabilizers, the design process considers a wide range of operating conditions. The effectiveness of the proposed controllers is verified through several linear and nonlinear analysis techniques. These techniques prove that the coordinated design of UPFC-based stabilizers is superior over any of the individual designs

Vascular complications following intra-aortic balloon pump implantation: an updated review

Background: The use of the intra-aortic balloon pump (IABP) as a support device remains controversial due to the fact that a number of studies have shown no benefit in end mortality whilst using this device. One of the reasons for this could be the increase in vascular complications when using the pump. Therefore, the aim of the present review was to assess the current literature available with regards to IABP vascular complications during the clinical situation. Methods: A literature search was performed, searching for IABP complications in adult human studies between 1990 and 2016. Results: A total of 20 reports were identified as fitting the criteria of this study. The majority of vascular complications were limb ischemia, bleeding or mesenteric ischemia. The overall incidence of vascular complications ranged from 0.94% to 31.1%. Diabetes, peripheral vascular disease and hypertension, as well as smoking were all identified as risk factors for complications following IABP. Furthermore, studies supported the use of sheathless balloon insertion to reduce the risk of complications. Conclusion: Major vascular complications, including limb and mesenteric ischemia as well as bleeding and hemorrhage, have been associated with IABP. However, the incidence of these complications was generally low. Further studies are still required to truly understand the risk/benefit associated with the use of IABP

Primary Raynaud's phenomenon in an infant: a case report and review of literature

Raynaud's phenomenon (RP) is an extremely unusual finding in early infancy. In the present report we describe a one-month-old previously healthy male infant who presented with unilateral acrocyanosis. Although infantile acrocyanosis is known to be a benign and self-resolving condition, it is generally bilateral and symmetric. The unilateral nature of the acrocyanosis was an atypical finding in this infant. Consequently, he was closely monitored to evaluate the progression of his acrocyanosis. Based on his benign clinical course and failure to demonstrate other etiologies contributing to his acrocyanosis, he was diagnosed to have primary RP. Due to the rarity of RP in children, we review the progress in understanding the pathophysiology, epidemiology and management of RP and additionally discuss the differential diagnosis of unilateral and bilateral acrocyanosis in infants

A Planning Model for an Electric Vehicle Aggregator Providing Ancillary Services to an Unbalanced Distribution Network Considering Contract Design

Recent advancements in battery technology have made them more economically viable than ever before, making them suitable for various grid-scale applications. Due to their rapid response, batteries are attractive for providing ancillary services (AS), such as frequency regulation and reserve services, to the bulk power grid. On the other hand, an electric vehicle (EV) is viewed as a moving battery; consequently, EVs are also suitable for those services. This research proposes a linear planning model for an Electric Vehicle Aggregator (EVA) within a distribution network (DN) to offer Ancillary Services (AS) to the bulk power grid. The model takes into account contract design by identifying optimal incentives or charging tariffs that Electric Vehicle (EV) owners would be willing to pay the EVA for charging their vehicles. Additionally, the model takes into account the size of the electric vehicle (EV) fleet as a crucial planning factor for EV aggregation that depends on the energy pricing set by the EVA. The proposed model is developed to maximize the overall profit of bidding capacities in the energy and AS markets while supporting the operation of an unbalanced DN by maintaining the DN limits. Simulation results and sensitivity analyses on the model have been carried out to support the investment model and investigate the change in the optimal solution across different case studies. Simulations show that the optimal charging tariff ( $\beta$ ) is ( $0.02~{\$}/kWh$ )when considering scenarios where Distribution Network (DN) limits, such as thermal and voltage constraints, are ignored for all EV participation versus $\beta$ relations. When including the DN, the optimal payoffs vary based on the relationship between the charging tariff and the number of participating EVs

Optimal charging strategies for unidirectional vehicle-to-grid using fuzzy uncertainties

Vehicle-to-grid (V2G) is a way to effectively integrate electric vehicles (EVs) with the power system network. Unidirectional V2G is especially attractive because it is easily implementable and requires little additional hardware. An EV can be effectively charged during its parking time, and can potentially generate revenues for the EV owner. It can also provide services to the electrical grid through an aggregated scheme. The aggregator combines the capacity of many EVs and bids them into electricity markets. In this paper, a novel charging scheme is proposed that optimizes the charging of EVs and the bidding of ancillary service in the electricity market, considering the different market uncertainties using fuzzy set theory. The electricity market parameters are forecasted using ARIMA models. Simulations performed on a hypothetical group of EVs in the ERCOT area show the benefits of the proposed scheme