Percentage Of Penetration Research Articles

Comparison of sealer penetration of sonic activation versus conventional needle irrigation: a systematic review and meta-analysis of randomized controlled trials

BackgroundMost existing studies comparing the efficiency of sonic irrigation (SI) and conventional needle irrigation (CNI) in increasing the penetration of sealers into dentine tubules are controversial; and this study aimed to determine whether the use of SI can lead to greater sealing ability than CNI, during the root canal treatment.MethodsThe EMBASE, PubMed, and Cochrane Library databases were used to find confocal laser scanning microscopy studies evaluating percentage and maximum depth of sealer penetration following the use of SI or CNI in mature permanent teeth until October 2022. The critical estimative checklist of randomized controlled trials of the standardized Joanna Briggs Institute was adopted to independently score the quality of each study. The random-effect model for meta-analysis was used to analyse for each canal segment (apical, middle, coronal). The results are shown in the forest plots as weighted mean differences (WMDs) with 95% confidence intervals (95% CIs).ResultsNinety-seven articles were included in the preliminary screening, and nine of them were included in this study. Eight studies were included in the meta-analysis.The meta-analysis exhibited great increases in the coronal (WMD: 8.09, 95% CI 2.78–13.40/WMD: 165.32, 95% CI 128.85–201.80), and middle segments (WMD: 8.81, 95% CI 5.76–11.87/WMD: 132.98, 95% CI 68.71–197.25) for the percentage and maximum depth of sealer penetration, respectively. The percentage of sealer penetration in the apical thirds region was nonsignificant (WMD: 4.73, 95% CI − 2.34–11.80). However, the maximum depth of sealer penetration in the apical thirds region was significant (WMD: 121.46, 95% CI 86.55–156.38). Chi-squared analysis revealed heterogeneity scores of 0.0–70.0% and 44.0–90.0% for the percentage and maximum depth of sealer penetration, respectively.DiscussionThis review verified that SI significantly improves tubular dentin sealer penetration in most areas of the root canal; thus, SI may lead to better filling efficiency and anti-reinfection effects than CNI during and after the root canal therapy. Nevertheless, a large heterogeneity in the current data comparing the irrigation efficiency of SI versus CNI in the apical third of the root canal was found, implying the necessity to standardize root canal irrigation procedures and obtain more accurate results in this area.Trial Registration: INPLASY database (INPLASY202270116).

Interfacial characteristics of BIOfactor MTA and Biodentine with dentin.

The objective of this study was to characterize the interface between dentin and MTA-Angelus (Angelus, Londrina, Brasil), Biodentine (Septodont, France) and BIOfactor MTA (Imicryl, Konya, Turkey) using scanning electron microscopy (SEM), energy disperse X-ray spectroscopy (SEM-EDS) and confocal laser scanning microscopy (CLSM). Fifteen dentin segments were obtained from previously extracted single-rooted human teeth. Canal lumens were instrumented with diamond burs and then randomly filled with MTA-Angelus, Biodentine or BIOfactor MTA and placed in distilled water or Hanks' Balanced Salt Solution (HBSS) for 28-days. The samples were examined with SEM and the thickness of the interfacial layer measured. SEM-EDS analysis was performed to determine principal elemental composition of the material, dentin, and interfacial area. The marginal adaptation of cements to dentin was assessed by confocal microscopy and the percentage of material penetration was calculated. An interfacial layer was evident in approximately 70% of SEM images in both MTA-Angelus and BIOfactor samples. The thickness of interfacial layer was significantly higher in HBSS than in distilled water for all groups. MTA Angelus resulted in the thickest interfacial layer in distilled water while Biodentine had the thickest interfacial layer in HBSS. Calcium levels within the BIOfactor MTA-dentin interface were higher than both dentin and cement. Dentin penetration was higher in BIOfactor MTA and silicon was evident in all material-dentin interfaces. All calcium silicate-based materials promoted the formation of an interfacial layer. BIOfactor MTA exhibited promising characteristics with its good marginal adaptation even though it presented a moderately thick interfacial layer. RESEARCH HIGHLIGHTS: A distinguishable interfacial layer was observed in most of the samples within the BIOfactor MTA, MTA-Angelus and Biodentine groups. The elemental constitution of the interfacial layer was different from that of the calcium silicate based materials.

Assessment of the grid-related loss of offsite power to the nuclear power plants in the presence of wind farms

Grid stability affects the progression of loss of offsite power scenarios to the nuclear power plants, as the most dominant core-damage-inducing initiating event. The ever-increasing tendency toward integration of large-scale wind farms into the transmission systems drastically challenges their dynamic behavior.In this study, we proposed a dynamic-probabilistic framework to evaluate the effect of wind penetration scenarios on the frequency of occurrence of LOOP to the NPPs. We developed 30 initial grid states, including 3 wind penetration percentages, 5 operational loading levels, in both optimal and normal power flows.We estimated 150 GR-LOOP frequencies for 5 NPP locations upon 3Ph-Shc faults on the transmission lines. Extending from 1.3 × 10−7 to 9.6 × 10−5 (year)−1 for the safest to the riskiest situations, the mean GR-LOOP frequencies have been assessed as 1.74 × 10−5, 2.96 × 10−5, and 2.77 × 10−5 (year)−1, for grids with 0%, 10%, and, 20% penetration percentage of installed wind generation, respectively.Our results indicate the undeniable influence of variations in the operational loadings and the wind penetration percentage on the GR-LOOP frequency, in addition to the NPPs’ locations. Such intensification effect was more pronounced in instantaneous frequencies of unique states than in the averaged ones. Furthermore, we observed more outstanding growth in the corresponding values of optimal cases. Our findings suggested that the reliability of the offsite grid to the NPPs be considered as a decision-making criterion, in addition to the existing security and economic issues in the grids with wind penetration.

Development of active biodegradable films based on chitosan and essential oil to prevent infestation of Plodia interpunctella (Lepidoptera: Pyralidae)

Plodia interpunctella Hübner (Lepidoptera: Pyralidae) is probably the most common moth pest of stored products. Its larvae are considered very effective packaging penetrators, causing serious losses. Therefore, the development of new food packaging technologies to prevent larvae infestation is crucial. In the present work, geranium and peppermint essential oils (EO) were used to elaborate chitosan (Qx) based films (Qx-EO films) at different concentrations (0% (control), 0.1%, 0.25% and 0.5% w/w). The Qx-EO films were tested in repellent and penetration assays for 72 h and 15 days, respectively. In both bioassays, most effective Qx-EO films were those containing geranium and peppermint EO at 0.5% w/w. In repellent assays, Qx-geranium EO films were more effective than Qx-peppermint EO films. In penetration assays, both films reduced penetration percentage to 10% (penetration percentage for control ≈ 50%). Then, possible structural changes, thermal stability and mechanical properties of Qx films containing EOs at 0.5% w/w were analyzed. The loading efficiency of Qx-geranium EO and peppermint EO films were close to 90% and 35%, respectively. It was demonstrated that EO incorporation allows conserving mechanical properties of control films. It is important to emphasize that these films showed repellent activity and could prevent contamination with P. interpunctella larvae.

Research on the Impacts of Vehicle Type on Car-Following Behavior, Fuel Consumption and Exhaust Emission in the V2X Environment

The type of vehicles in realistic traffic systems are not homogeneous. Impacts of the preceding vehicle’s type on the car-following behavior, fuel consumption and exhaust emissions are still unclear. This paper presents a study on the impacts of two types of preceding vehicles, heavy vehicles and new energy vehicles, on car-following behavior, traffic flow characteristics, fuel consumption and exhaust emissions. Firstly, an extended car-following model was proposed by incorporating the influence of the preceding vehicle’s type. Secondly, impacts of the preceding vehicle’s type on platoon stability were analyzed by applying linear stability theory. Finally, numerical simulations were carried out to analyze impacts of the preceding vehicles’ type on the characteristics of the car-following platoon, traffic flow operation, and vehicle’s fuel consumption and exhaust emissions. The results reveal that, compared with the normal preceding vehicle, there are negative impacts of the heavy and new-energy preceding vehicles on the platoon stability, traffic flow operation, and vehicle’s fuel consumption and exhaust emissions, and these impacts are related to the corresponding sensitivity parameters and the penetration percentages of the two types of preceding vehicle. The research results of this paper can provide a reference for understanding car-following behavior and traffic-flow characteristics affected by the type of preceding vehicles in the V2X environment.

Effect of UV LED Intensity on The Growth of Red Lettuce in Indoor Hydroponics

Microclimate control is increasingly widespread in limited agricultural environments. This is especially important for the cultivation of plants that tolerate significantly different thermal and hygrometric conditions. Nevertheless, there is much to be done in automation and control technology in this area to achieve the best results in both quantitative and qualitative terms of the product. This applies especially to horticultural crops that are sensitive to the cultivation environment and microclimate. This work aims to characterize the microclimate parameters in a confined agricultural environment with perforated ducts for air conditioning supply. For this work, a microclimate control unit was used instead of a lettuce crop. It was placed into a confined agricultural environment at different locations in the space to obtain the main microclimate parameters. After setting the input of the microclimate environment, the instrument measured a series of physical quantities (temperature, radiant temperature, humidity, and air velocity). Tests were carried out by taking the optimum day temperature constant for growing lettuce and by varying the supply airflow rate by setting the fan speed at 30%, 50%, and 80%. The results of these tests are essential for performing real-time control of the microclimate environment and for managing parameters for optimization of the entire system. In addition, the air velocity test showed adequate velocity reduction and good air mixing. The values obtained are generally acceptable for indoor cultivation and the conditions created are suitable for growing plants in such an environment. Light is an essential need for plants so that plants can carry out the photosynthesis process properly. In indoor DWC hydroponics system, the source of UV light is LED lights for plants. Some of the advantages of using LED light include a small light spectrum, less heat production, low power consumption, and wavelengths of 660 m and 450 m that are needed by plants. This research project aims to create a DWC hydroponic system for growing red lettuce in an indoor hydroponics and see the effect of LED grow light on the growth of red lettuce. DWC hydroponics uses AB-Mix nutrients that are channeled through inch PVC pipes using pump power. The hydroponic rack used has a height of 1.7 m and a width of 40 cm and has 3 shelves, where each shelf has 9 nutrient containers. The red lettuce plants in the DWC system were provided with different light treatments by installing shading nets with different percentages of light penetration, namely, 75%, 50%, and 0%. From the results of these treatments, the average yield of red lettuce was 300 grams on the top shelf, 400 grams on the middle shelf, and 600 grams on the bottom shelf.

Optimal sizing of country-scale renewable energy systems towards green transportation sector in developing countries

In the context of refining countries’ transition plans toward 100% shares of renewable systems in the electric power grids by 2050, this study aims to investigate, for the first time, the potential of covering the increasing energy demand for electric vehicles (EVs) using the previously planned hybrid renewable energy system (RES) for Jordan, which comprised wind, solar photovoltaic (PV), and battery energy storage systems (ESS). The optimal RES sizing is revisited to examine the influence of EV penetration percentages and charging rates (normal, medium, and fast) and optimize the charging periods to reduce system capacity. The results showed that for typical nighttime charging and relatively smaller EV penetrations, the RES system capacity remains the same, but the size of ESS must be increased by up to 16.67% for 25% EV penetration. As EV penetration increases, the required ESS capacity drops slightly, but the RES capacity increases by up to 24.53% for 100% EV penetration. Optimal charging periods were found to be during morning hours (6:00 to 9:00 a.m.). Adopting these early charging hours and compared to 0% EV, the required ESS capacity remained nearly the same, except for smaller EV penetration percentages. However, for 100% EV penetration, the increase in required capacity ranged from 24.5% for fast charging to 50.01% for normal charging. For lower penetration percentages, the three modes of charging resulted in comparable capacities of ESS and RES. As the penetration percentage increased to 100%, the fast charging mode required considerably lower RES capacity (by 17.0%) and the same ESS capacity of the 0% EV penetration.

Carrier-Based Obturation: Effect of Sonication Technique on Sealer Penetration in Dentinal Tubules: A Confocal Laser Scanning Microscope Study

(1) Background: In endodontics, anatomical complexities and irregularities in the root canal system may interfere with sealer penetration, increasing the risk of treatment failure. This work aimed to investigate the effects of sonicated Thermafil (Dentsply, Tulsa Dental Specialties, Johnson City, TN, USA) on sealer penetration into the dentinal tubules. (2) Methods: Thirty teeth with single round-shaped root canals were used to compare Sonicated Thermafil with sonication (ST—10 teeth), System B (EIE Analytical Technology, Orange, CE, USA) (SB—10 teeth), and Thermafil without sonication (T—10 teeth). A confocal laser scanning microscope (CLSM) was used to determine the depth, area, and percentage of sealer penetration into the dentinal tubules. (3) Results: ST showed the deepest average penetration at 6 mm from the apex compared to SB (p < 0.01) and T (p < 0.01) and at 3 mm compared to SB (p < 0.01). In addition, it had the highest penetration values at both levels compared to SB (p < 0.01) and T (p < 0.05) and a higher penetration area at 6 mm compared to T (p < 0.05) and SB (p < 0.05). (4) Conclusion: Sonic activation can improve the carrier-based obturation technique thanks to deeper sealer penetration and thus better retention of materials.

Assessment of Blood Flow Transport in the Left Ventricle Using Ultrasound. Validation Against 4-D Flow Cardiac Magnetic Resonance.

Four-dimensional flow cardiac magnetic resonance (CMR) is the reference technique for analyzing blood transport in the left ventricle (LV), but similar information can be obtained from ultrasound. We aimed to validate ultrasound-derived transport in a head-to-head comparison against 4D flow CMR. In five patients and two healthy volunteers, we obtained 2D+t and 3D+t (4D) flow fields in the LV using transthoracic echocardiography and CMR, respectively. We compartmentalized intraventricular blood flow into four fractions of end-diastolic volume: direct flow (DF), retained inflow (RI), delayed ejection flow (DEF) and residual volume (RV). Using ultrasound we also computed the properties of LV filling waves (percentage of LV penetration and percentage of LV volume carried by E/A waves) to determine their relationships with CMR transport. Agreement between both techniques for quantifying transport fractions was good for DF and RV (Ric [95% confidence interval]: 0.82 [0.33, 0.97] and 0.85 [0.41, 0.97], respectively) and moderate for RI and DEF (Ric= 0.47 [-0.29, 0.88] and 0.55 [-0.20, 0.90], respectively). Agreement between techniques to measure kinetic energy was variable. The amount of blood carried by the E-wave correlated with DF and RV (R=0.75 and R=0.63, respectively). Therefore, ultrasound is a suitable method for expanding the analysis of intraventricular flow transport in the clinical setting.

An automatic fault section identification method based on distributed traveling wave sensors

As electrification deepens and the society relies more and more on electricity, dependability and safety standard of the power distribution system becomes higher and higher. What is more, to minimize carbon emission, high percentage of renewable energy resources penetration is becoming a reality, which further complicates the distribution system. Because of equipment failure, construction mistake and other causes, power system faults are inevitable. Fault section identification and fault isolation is a critical mission in distribution system operation [1]. As the distribution system develops and evolves, two main ways to accomplish this goal were established: (a) Substation overcurrent relay detects the fault and the corresponding substation breaker isolates the fault. Then trial-and-error method is used to identify and isolate the fault section; (b) Distributed sensors are deployed in the distribution system. Distribution system automation software in the operation center then collects fault information sent from all the distributed sensors. Operation stuff make a judgement on the fault section and fault isolation is done on a remote control or manual operation fashion. These methods leave a lot of room for improvements, which will be elaborated in section II. In this paper, integrated usage of fundamental frequency signals and traveling waves signals is done for fault detection and fault type identification in distributed sensors. And then an automatic fault section identification algorithm is introduced. This algorithm does not require human intervention, which reduces outage time, saves manual efforts and also lays the foundation for automatic electricity restoration.

Primary failure of eruption (PFE) - a systematic literature review

Introduction and purpose
 Primary Failure of Eruption (PFE) is a rare disease that occurs more often in women than in men. PFE is extremely important for orthodontists because conventional treatment of patients results in ankylosis of the teeth affected by the disease. The aim of the study is to discuss the epidemiology, etiology, diagnosis and treatment of Primary Failure of Eruption.
 Description of the state of knowledge
 PFE is present in 0.05% to 0.6% of the population. The average incidence is at the age of 13.65, more often in women. Most often it affects the lateral teeth, and therefore it results in open lateral bites because the teeth do not reach the occlusal plane. The condition was found to be of genetic origin and inherited autosomal dominantly with a low percentage of incomplete penetration. The gene responsible for the disease is the PTH1R. The diagnosis of the disease consists in excluding other causes of eruption failure, detecting disease in which such symptoms occur, and genetic tests (NGS). Treatment of an open lateral bite cannot be carried out in a conventional manner due to the deterioration of the condition after the application of orthodontic forces. The result of the above actions is ankylosis of teeth covered by PFE. The currently proposed methods of treatment are: single or multi-site osteotomy, selective extractions with subsequent implantations, direct or indirect composite restorations, distraction osteogenesis, removable prosthetic restorations.
 Summary
 Properly conducted clinical examination of the patient should take into account PFE. Genetic testing (PTH1R) is important in the diagnosis of people with eruption disorders, which is crucial for achieving partially positive treatment results. Orthodontic treatment is contraindicated and patients with a PTH1R mutation should be monitored long-term until their growth is complete, which is the time when interdisciplinary treatment is initiated.

Dentin Sealing of Calcium Silicate-Based Sealers in Root Canal Retreatment: A Confocal Laser Microscopy Study.

The aim of the present in vitro study was to evaluate the intratubular penetration of three bioceramic sealers in root canal retreatment. Here, 30 single-rooted human teeth were instrumented with the Protaper Universal system and filled with gutta-percha and the epoxy-resin-based sealer AH Plus mixed with rhodamine B. After two weeks in a humid environment, they were re-instrumented with Reciproc Blue and divided into three groups according to the endodontic sealer to be used in the re-filling (n = 10): G1: CeraSeal, G2: TotalFill BC Sealer, G3: TotalFill BC Sealer HiFlow. For the filling, a single cone technique was used, and the respective sealers were mixed with fluorescein. The roots were then sectioned at 2, 5, and 8 mm (apical, medial, and coronal measurement points, respectively) from the apex, and the dentinal tubule penetration depth and percentage of penetration around the canal perimeter were evaluated by means of confocal laser scanning microscopy (CLSM). Penetration between groups was compared using the Kruskal−Wallis test, and within each group using the Wilcoxon test. Statistical significance was established at p < 0.05. A non-significant reduction was found in the penetration depths and in a percentage of penetration around the canal perimeter between AH Plus and the tested calcium-silicate-based sealers (p > 0.05). Consequently, this reduction may not affect the three-dimensional seal of the root canal system in a negative manner. The penetration depth and percentage of penetration around the canal perimeter at both the root canal treatment and retreatment were significantly reduced from the coronal to apical points in all groups (p < 0.05).

The Impact of Laser-Activated and Conventional Irrigation Techniques on Sealer Penetration into Dentinal Tubules.

Objective: The present study was aimed at comparing the efficacy of 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP) and ethylenediaminetetraacetic acid (EDTA) by using various final irrigation techniques on penetration of sealer. Background: Traditional irrigation of root canals with a syringe limits the ability of sealer penetration. Various irrigants and activation techniques, including sonic and ultrasonic devices and various kinds of lasers, have been introduced to improve penetration of sealers into dentinal tubules. Methods: One hundred mandibular premolars were selected. Final irrigation was performed with HEDP or EDTA by conventional syringe irrigation (CI), EndoActivator (EA), passive ultrasonic irrigation (PUI), photon-induced photoacoustic streaming (PIPS), and shock wave-enhanced emission photoacoustic streaming (SWEEPS) methods (n = 10). After obturation of root canals with the EndoSequence BC Sealer, samples were evaluated using a confocal laser scanning microscope (CLSM), which enabled measurement of the maximum depth, percentage, and penetration area. Tests performed for analysis included the Kruskal-Wallis H and Mann-Whitney U tests. Results: In the EA method, the penetration percentage achieved using HEDP was significantly higher than EDTA at both sections (p < 0.05). Irrespective of the final irrigation solution employed, the PUI, PIPS, and SWEEPS techniques exhibited greater tubule penetration values compared with the CI and EA techniques (p < 0.05). Conclusions: HEDP and EDTA showed similar effects on the amount of penetrated sealer into the dentinal tubules, and the PUI, PIPS and SWEEPS methods provided enhanced EndoSequence BC Sealer penetration compared with the CI and EA methods. This study was approved by the Near East University institutional review board (#2020/86-1225).

The impact of truck platooning action on asphalt pavement: a parametric study

ABSTRACT Partially/fully self-driven trucks in platoon configurations promise to increase transport efficiency, reduce fuel consumption/gas emissions and improve road safety through the use of connectivity technologies and automated driving support systems. However, truck platooning means the introduction of new types of loads on pavements which are characterised by: multiple loads, generated by the multi-axle configurations of the different trucks forming the platoon, traffic channelisation by the reduction of the lateral deviation of the trucks, and reduced inter-truck time gaps, which may reduce the self-recovery capacity of asphalt concrete materials, reducing the pavement service life. In this context, this study presents a parametric analysis carried out to evaluate a pavement structure subjected to several platoon truck configurations. The results of the study indicated that to keep the same pavement structural response as for individual trucks, it is possible to act on the following parameters in the platoon configuration: traffic distribution along the year and along the time of the day (avoiding traffic at higher temperatures), percentage of platoon penetration in the daily and annual traffic, level of loading of the trucks, number of trucks in platoon configuration, wandering, and inter-truck time-gaps/distances.

Preparation, Characterization and Permeation Study of Topical Gel Loaded with Transfersomes Containing Asiatic Acid.

The objective of this study is to investigate the in vitro permeation of asiatic acid (AA) in the form of a topical gel after entrapment in transfersomes by Franz diffusion cells. Transfersomes composed of soybean lecithin and three different edge activators including Tween 80 (TW80), Span 80 (SP80) and sodium deoxycholate (SDC) at the ratio of 50:50, 90:10 and 90:10, respectively, together with 0.3% w/w of AA, were prepared by a high-pressure homogenization technique and further incorporated in gels (TW80AATG, SP80AATG and SDCAATG). All transfersomal gels were characterized for their AA contents, dynamic viscosity, pH and homogeneity. Results revealed that the AA content, dynamic viscosity and pH of the prepared transfersomal gels ranged from 0.272 ± 0.006 to 0.280 ± 0.005% w/w, 812.21 ± 20.22 to 1222.76 ± 131.99 Pa.s and 5.94 ± 0.03 to 7.53 ± 0.03, respectively. TW80AATG gave the highest percentage of AA penetration and flux into the Strat-M® membrane at 8 h (8.53 ± 1.42% and 0.024 ± 0.008 mg/cm2/h, respectively) compared to SP80AATG (8.00 ± 1.70% and 0.019 ± 0.010 mg/cm2/h, respectively), SDCAATG (4.80 ± 0.50% and 0.014 ± 0.004 mg/cm2/h, respectively), non-transfersomal gels (0.73 ± 0.44 to 3.13 ± 0.46% and 0.002 ± 0.001 to 0.010 ± 0.002 mg/cm2/h, respectively) and hydroethanolic AA solution in gel (1.18 ± 0.76% and 0.004 ± 0.003 mg/cm2/h, respectively). These findings indicate that the TW80AATG might serve as a lead formulation for further development toward scar prevention and many types of skin disorders.

PREPARATION AND CHARACTERIZATION OF ITRACONAZOLE TRANSDERMAL PATCHES CONTAINING SINGLE-PHASE EMULGEL

Objective: Emulgel technique has attempts for preparation of itraconazole (ITZ) transdermal patches of reservoir type using a single-phase system with different polymers of Carbopol 934 and Carboxy methyl cellulose (CMC).&#x0D; Methods: The transdermal patches were prepared by using eudragit L30 as a polymer and propylene glycol (PG) as plasticizer has been made to predict the mechanism of drug release and absorption based on the order of release. The optimized transdermal patches were characterised as surface morphology, pH, viscosity, spreadability, folding endurance, drug permeation, assay, in vitro dissolution and stability for 3 mo.&#x0D; Results: The result of the study showed that the transdermal patches prepared with eudragit (8 %) showed 96.11±3.17 % drug release in 24 h and the optimised formulation F8, which had the highest concentration of span 20 and tween 20, displayed the highest percentage of drug penetration. The drug release kinetics was studied, including the Baker-Lonsdale model with in vitro drug permeation data was found that release from non-spherical matrices, the first-order model with non-fickian diffusion.&#x0D; Conclusion: ITZ administered transdermally might be avoided the number of drawbacks associated with oral delivery and perhaps maintain a relatively constant plasma level during a lengthy course of treatment.

Bi-level planning and scheduling of electric vehicle charging stations for peak shaving and congestion management in low voltage distribution networks

Most existing algorithms for electric vehicle charging station (EVCS) planning and scheduling of electric vehicles (EVs) do not consider the uncertain behavior of EVs and distribution networks, including the EV arrival and departure times, user driving needs, and realistic residential load and generation profiles. This paper proposes a bi-level planning and operation framework that determines the optimal locations of EVCS and scheduling of EVs to reduce peak load and network congestion in low voltage distribution networks by considering uncertain EV and distribution network behavior. Planning of EVCS is performed to minimize voltage deviations and distribution network losses. The priority-based scheduling algorithm uses the vehicle-to-grid (V2G) and grid-to-vehicle (G2V) technology to charge the EVs during high priority periods to meet the user requirements and discharge during low or medium priority periods to reduce the peak load and thermal overloading in distribution feeders. Based on an Australian scenario, the proposed method has been tested on the IEEE low voltage test feeder. Uncoordinated scheduling of EVs is also implemented and compared with the proposed strategy. The results show that installing EVCS at the optimal locations can reduce the network losses and voltage deviations by 39.38 per cent and 15.32 per cent, respectively. It is also shown that the proposed scheduling of EVs can reduce the peak load of distribution substations and lower the network congestion without affecting the EV charging requirements. With a 55 percent penetration of EVs, the peak load and thermal overload in distribution lines are reduced by 20.53 per cent and 5.88 per cent, respectively.

Effects of various agitation techniques on sealer penetration in dentinal tubules using CLSM

Aim: To compare the effect of ultrasonic, sonic and rotary sealer activation techniques on depth of penetration of sealer in the dentinal tubules. Materials and Methods: Freshly extracted 60 single rooted human permanent mandibuar premolar with mature apex were collected. A size 10 no. K file (Dentsply Maillefer) was introduced into each canal. The irrigation procedure was accomplished by using 2ml of 5.25% NAOCl for each file used. Roots were randomly divided into 3 groups on the basis of sealer activation techniques. The specimens were kept in incubator at 37 degree Centigrade temperature for 2 days. The dentin segments were examined on a confocal microscope in Jawaharlal Nehru University, New Delhi under 4X,10X magnification. Results: A total of 60 teeth were included in the study and they were divided into three groups on the basis of method of agitation of sealer: GROUP I - Lentulospiral, Group II-Ultrasonic endodontic tip, Group III - Endoactivator and obturation was done with gutta percha. Mean percentage and depth of penetration was greatest in Group II i.e. Ultrasonics when used for agitation and statistically significant than Group I lentulospiral and Group III Endoactivator.

Intratubular Sealer Penetration: Scanning Electron Microscopy Associated with Cathodoluminescence Analysis

The aim of the study was to compare the ability of three endodontic sealers, Endofill (END), AH Plus (AHP), and Sealer Plus BC (SPB), to penetrate dentinal tubules. Forty-five human teeth, single-rooted and previously instrumented mandibular premolars, were randomly divided into three experimental groups (n = 15): END (n = 15), AHP (n = 15), and SPB (n = 15). After obturation, dental sections were performed horizontally, at 2 and 5 mm from the root apex. The samples were analyzed by scanning electron microscopy associated with cathodoluminescence. Percentage penetration (PP%) and maximum penetration depth (MPD) of the sealers were evaluated by the Kruskal-Wallis and Mann-Whitney tests, for general and paired data, respectively. The Wilcoxon test was applied to analyze the differences between the 5 and 2 mm distances. A 5% significance level was adopted. As for PP%, AHP and SPB were similar (p = 0.127) and presented higher values than END (AHP, p = 0.024 and SPB, p <0.001); with regard to MPD, AHP and SPB did not differ either (p = 0.450), but were higher than END (p <0.001); in both analyses, penetration was greater at 5 mm than at 2 mm (p <0.001). SPB showed satisfactory performance in penetrating dentinal tubules, being similar to AHP, and superior to END. Greater penetration of sealer into the dentinal tubules may increase the chance of successful endodontic treatment.

Effect of Different Obturation Techniques on Sealer Penetration into Dentinal Tubules after Final Irrigation with XP-Endo Finisher File

The first objective of this research was to evaluate the effectiveness of XP-Endo Finisher on dentinal tubule penetration of irrigation solution using confocal laser scanning microscopy. The main purpose of this research was to compare the effect of cold lateral condensation, continuous wave obturation and core-carrier based techniques on sealer penetration. Sixty mandibular premolars were prepared and allocated into two experimental groups (n=30) as the final irrigation technique and obturation technique experiment. In the final irrigation technique experiment, final irrigation was performed with XP-Endo Finisher, passive ultrasonic irrigation (PUI) and conventional needle irrigation (CNI) (n=10). The roots in the obturation technique experiment were also assigned into 3 groups and obturated with cold lateral condensation, continuous-wave obturation and core-carrier techniques (n=10). The most effective activation method, which emerged as a result of the first part of this study, was used as the final irrigation method in the obturation technique experiment. Then, all roots were sectioned in 1-mm-thick slices at 3mm from the apex for scanning. In terms of depth and percentage of material penetration, CNI exhibited significantly the lowest values and no significant difference was found between others. Also, there was no significant difference among obturation methods. In conclusion, XP-Endo Finisher and PUI are more effective than CNI on irrigant penetration. Sealer penetration into dentinal tubules is independent of obturation techniques.