Procedural Errors Research Articles

Position and Orientation Errors in a Neuronavigation Procedure: A Stepwise Protocol Using a Cranial Phantom

Neuronavigation procedures demand high precision and accuracy. Despite this need, there are still few studies analyzing errors in such procedures. The aim of this study was to use a custom-built cranial phantom to measure target position and orientation errors in different phases of a simulated neuronavigation procedure. A cranial phantom with 10 target sites was designed and imaged with computed tomography and magnetic resonance. A segmentation of a cloud of points of the phantom (ground truth) was obtained using an optical tracking system and compared with the images (imaging phase). Targets and trajectories were then planned with neuronavigation software and compared with the ground truth (planning phase). The same plan was used to identify the points in real space after image-to-phantom registration and calculate the final error of the procedure by comparison with the ground truth (registration and execution phase). The mean errors after the imaging phase were 1.11 ± 0.42 mm and 3.23° ± 1.69° for position and orientation, respectively. After planning the mean errors were 1.10 ± 0.39 mm and 5.55° ± 2.91°. The global errors after the registration and mechanical execution were 3.93 ± 1.70 mm and 3.65° ± 1.29°. After a stepwise analysis, registration and mechanical execution were the main contributors to the global position error.

EFEKTIVITAS DISTRACTOR PADA TES PILIHAN GANDA UNTUK MENDETEKSI KESALAHAN SISWA DALAM MENYELESAIKAN SOAL MATEMATIKA

The aim of this study is to determine the effectiveness of the distractor on multiple choice tests to detect the students’ errors and the types of errors students made in solving math problems. This research is a descriptive qualitative study which research subjects were students of class IX MTsN Model Banda Aceh that consisted of 36 students, then three students were selected as subjects to be interviewed about mastery and mistakes made when completing math problems. Data were collected through tests and interviews which validity was used to test the credibility of the data by means of triangulation. Data analysis consisted of the stages of data reduction, data presentation, and conclusion drawing. The results showed that: 1) A good distractor on multiple choice tests had been completed such as a description test question for each answer option chosen by the students was very effective for detecting students’ errors in solving mathematics problems, in which 17.1% of students incorrectly applied mathematical concepts , 3.7% of students made mistakes due to lack of accuracy or error, 1.2% of students misunderstood the problem, and 4.7% of students did not make a solution, but only guessed from the ten questions given. 2) Conceptual errors made by the three subjects (MAH, BSR, and PES) were errors in analyzing the combined area of space and errors in algebraic factorization. Errors in understanding and applying the difference formula were only done by the subject MAH, errors in determining the square root of a number were only done by the subject BSR, and errors in squaring a number were only done by the subject PES. While procedural errors due to lack of thoroughness or error in substituting a value were carried out by subject MAH and PES, errors due to the inability to manipulate steps to solve a problem were only carried out by the subject MAH, and errors in writing the final results were only done by the BSR subject.

Crop Coefficients and Transpiration of a Super Intensive Arbequina Olive Orchard using the Dual Kc Approach and the Kcb Computation with the Fraction of Ground Cover and Height

The SIMDualKc model was used to simulate crop water requirements for a super high density olive orchard in the region of Alentejo, Portugal. This model uses the dual crop coefficient approach to estimate and partitioning the actual crop evapotranspiration (ETc act) and therefore to perform the soil water balance. The model was calibrated with 2011 tree transpiration using trunk sap flow measurements and was validated using similar data from 2012 and tested with 2013 data. Low root mean square errors (RMSE < 0.53 mm·d−1) and acceptable modelling efficiency indicators (EF > 0.25) were obtained. Further validation was performed comparing modelled ETc act with eddy covariance measurements. These indicators support the appropriateness of using SIMDualKc to guide irrigation management. The basal crop coefficient (Kcb) curves obtained with SIMDualKc for those 3 years were compared with the Kcb values computed with the Allen and Pereira approach (A&P approach) where Kcb is estimated from the fraction of ground cover and plant height considering an adjustment factor for crop stomatal control (Fr). Fr values were obtained through a trial and error procedure through comparing the Kcb estimated with this approach and with SIMDualKc. The Kcb curves obtained by both methods resulted highly correlated, which indicates that the A&P approach may be used in the irrigation management practice to estimate crop water requirements. Results of performing the soil water balance with SIMDualKc have shown that soil evaporation is a large fraction of ETc act, varying between 41% and 45% for the 3 years under study. Irrigation, applied with a drip system, represented 39 to 56% of ETc act, which shows the great importance of irrigation to achieve the water requirements of super intensive olive orchards. Nevertheless, the analysis has shown that the irrigation management adopted at the orchard produces a water deficit larger than desirable, with a ratio of ETc act to non-stressed crop evapotranspiration (ETc) varying from 70% to 94% during the mid-season, when that ratio for a eustress irrigation management could be around 90%.

Oil price Fluctuation, Gold Returns and Inflationary Pressure: An Empirical Analysis Using Cointegration Approach

Given that oil and gold prices are the major representative for commodity market, they both play a crucial role in determining the level of consumption, industrial production and investment due to the direct effect by the changes in their prices. In addition, both oil and gold prices have inflationary pressure which has a direct impact on countries economic growth. Therefore, it is of crucial practical significance to analyze their cointrgration relationships to understand the co-movement of both prices. To do so, this paper aims to examine the impact of oil price fluctuation on gold prices taking into account the inflationary pressure in the United States (US). Using monthly data from April, 1986 to September, 2018, Johansen multivariate cointegration test procedure and vector error correction model (VECM) have been employed to examine the long-run relationship between the variables in the US. The key findings suggest that there is a significant positive long run relationship between crude oil prices, gold prices and inflation. In the short run, the impact of any changes in crude oil prices will have a delayed effect on the prices of gold, while the impact of inflation in not different from zero. In addition, both gold prices and inflation are found to have no impact on gold prices in the short run. The findings of this research are important for investors, portfolio managers, corporate houses, crude oil traders, the government and policy makers.

Characteristics of seventh grade students’ pseudo thinking in solving mathematical reasoning about number operation based on mindset

Pseudo construction thinking occurs when students assume that true/false belief is actually not totally true/false. The study aimed to describe the characteristics and causes of students’ pseudo thinking in solving mathematical reasoning about number operation based on mindset. This research was descriptive qualitative research. The subjects of this study were 30 Junior High School students in Kebumen. Data collection techniques used mathematical reasoning test, questionnaire mindset, and interview. The mathematical reasoning test was constructed with making a conjecture as indicators. Questionnaire of mindset adapted from Mindset Work. Interviews were used to support the validity of data related to subjects indicated to have pseudo. Based on the result of the research: (1) there are 20 students with growth mindset and 10 students with fixed mindset; (2) fixed mindset students do false pseudo, 3) growth mindset students do both types of pseudo and 4) the cause of these pseudo are conceptual and procedural error.

Computing FAO56 reference grass evapotranspiration PM-ETo from temperature with focus on solar radiation

The computation of the reference crop evapotranspiration (ETo) using the FAO Penman-Monteith equation (PM-ETo) requires data on maximum and minimum air temperatures (Tmax, Tmin), vapour pressure deficit (VPD), solar radiation (Rs) and wind speed at 2 m height (u2). However, those data are often not available, or data sets may be incomplete or have questionable quality. Various procedures were proposed in FAO56 to overcome these limitations and an abundant literature has been and is being produced relative to alternative computational methods. Studies applied to a variety of climates, from hyper-arid to humid, have demonstrated that improved methods to compute PM-ETo from temperature only (PMT approach) have appropriate accuracy. These methods refer to estimating: (i) the dew point temperature (Tdew) from Tmin or, in case of humid climates, from the mean temperature, Tmean; (ii) Rs from the temperature difference (TD = Tmax-Tmin); and (iii) u2 using default global or regional values. Greater difficulties refer to the need for locally calibrating the radiation adjustment coefficient (kRs) used with the Rs equation. Therefore, considering that calibrated kRs values were made available by past studies for a large number of locations and diverse climates, the current study developed and tested simple computational approaches relating locally calibrated kRs with various observed weather variables – TD, relative humidity (RH) and average u2. The equations were developed using CLIMWAT monthly full-data relative to all the Mediterranean countries. The equations refer to all available data, or to data grouped as hyper-arid and arid, semi-arid, dry and moist sub-humid, and humid climates. To test those kRs equations, ETo computed from temperature and using the predicted kRs values were compared with ETo computed with full data sets of the same Mediterranean locations and of Iran, Inner Mongolia, Portugal and Bolivia. RMSE average values result then small, ranging from 0.34 to 0.54 mm day−1, therefore not very far from values obtained when a trial and error procedure was used for all the same locations, from 0.27 to 0.46 mm day−1. These indicators allow to propose the use of kRs obtained from the predictive equations instead of locally calibrated kRs values, which greatly eases computations and may largely favour the use of the PMT approach.

Cognition errors in the treatment course of patients with anastomotic failure after colorectal resection

BackgroundCognitive errors have a considerable effect on procedural outcome. They play a major role in situational judgement and decision making, especially during cognitively demanding tasks. As such they need to be considered an important factor in medical and surgical procedures. However, whereas cognitive diagnostic errors are well known, as of yet the occurrence of errors due to cognitive heuristics may have been downplayed, underestimated, or simply been ignored during the course of surgical treatment.MethodsAll colorectal resections with anastomosis in 2015 and 2016 (n = 230) were prospectively screened for anastomotic failure (n = 17/230). During structured Morbidity and Mortality Conferences (MMC) all anastomotic failures were analyzed for both tactical and technical decisions in the pre- and intraoperative setting with potential meaning for the postoperative course, based on the London Protocol. In order to demonstrate the significance of cognitive errors in surgical procedures a structured interview with the individual surgeon was conducted including the video and photo documentation of the individual surgical procedure. The interviews were coded by independent coders who were instructed to identify defined cognitive errors. Inter-coder agreement was calculated using Krippendorff’s alpha.ResultsIn 12/17 patients with anastomotic failure after colorectal surgery tactical or technical decisions with potential negative influence on anastomotic healing or the postoperative course were assessed during MMC. In 8/12 procedures a structured interview could be conducted with the operating surgeon. In 7/8 procedures cognitive errors could be identified. In particular we found Anchoring (n = 1), Availability Bias (n = 1), Commission Bias (n = 1), Overconfidence Bias (n = 1), Omission Bias (n = 2) and Sunk Costs (n = 1).ConclusionCognitive errors seem to play an important role during surgical therapy of patients with anastomotic failure after colorectal resection. Consequently, we suggest cognitive errors should attract more interest in research as well as attention in clinical practice.

Defining a new neurosurgical complication classification: lessons learned from a monthly Morbidity and Mortality conference.

The absence of a commonly accepted standardized classification system for complication reporting confounds the recognition, objective reporting, management, and avoidance of perioperative adverse events. In the past decade, several classification systems have been proposed for use in neurosurgery, but these generally focus on tallying specific complications and grading their effect on patient morbidity. Herein, the authors propose and prospectively validate a new neurosurgical complication classification based on understanding the underlying causes of the adverse events. A new complication classification system was devised based on the authors' previous work on morbidity in endovascular surgery. Adverse events were prospectively compiled for all neurosurgical procedures performed at their tertiary care academic medical center over the course of 1 year into 5 subgroups: 1) indication errors; 2) procedural errors; 3) technical errors; 4) judgment errors; and 5) critical events. The complications were presented at the monthly institutional Morbidity and Mortality conference where, following extensive discussion, they were assigned to one of the 5 subgroups. Additional subgroup analyses by neurosurgical subspecialty were also performed. A total of 115 neurosurgical complications were observed and analyzed during the study period. Of these, nearly half were critical events, while technical errors accounted for approximately one-third of all complications. Within neurosurgical subspecialties, vascular neurosurgery (36.5%) had the most complications, followed by spine & peripheral nerve (21.7%), neuro-oncology (14.8%), cranial trauma (13.9%), general neurosurgery (12.2%), and functional neurosurgery (0.9%). The authors' novel neurosurgical complication classification system was successfully implemented in a prospective manner at their high-volume tertiary medical center. By employing the well-established Morbidity and Mortality conference mechanism, this simple system may be easily applied at other neurosurgical centers and may allow for uniform analyses of perioperative morbidity and the introduction of corrective initiatives.

Procedural errors in endodontic treatment: analysis of preclinical step-back preparation performed on training blocks

ENWEndNote BIBJabRef, Mendeley RISPapers, Reference Manager, RefWorks, Zotero AMA Lehmann A, Nijakowski K, Eliasz W, Surdacka A. Procedural errors in endodontic treatment: analysis of preclinical step-back preparation performed on training blocks. Journal of Stomatology. 2019;72(6):256-262. doi:10.5114/jos.2019.93845. APA Lehmann, A., Nijakowski, K., Eliasz, W., & Surdacka, A. (2019). Procedural errors in endodontic treatment: analysis of preclinical step-back preparation performed on training blocks. Journal of Stomatology, 72(6), 256-262. https://doi.org/10.5114/jos.2019.93845 Chicago Lehmann, Anna, Kacper Nijakowski, Wojciech Eliasz, and Anna Surdacka. 2019. "Procedural errors in endodontic treatment: analysis of preclinical step-back preparation performed on training blocks". Journal of Stomatology 72 (6): 256-262. doi:10.5114/jos.2019.93845. Harvard Lehmann, A., Nijakowski, K., Eliasz, W., and Surdacka, A. (2019). Procedural errors in endodontic treatment: analysis of preclinical step-back preparation performed on training blocks. Journal of Stomatology, 72(6), pp.256-262. https://doi.org/10.5114/jos.2019.93845 MLA Lehmann, Anna et al. "Procedural errors in endodontic treatment: analysis of preclinical step-back preparation performed on training blocks." Journal of Stomatology, vol. 72, no. 6, 2019, pp. 256-262. doi:10.5114/jos.2019.93845. Vancouver Lehmann A, Nijakowski K, Eliasz W, Surdacka A. Procedural errors in endodontic treatment: analysis of preclinical step-back preparation performed on training blocks. Journal of Stomatology. 2019;72(6):256-262. doi:10.5114/jos.2019.93845.

УЧАСТЬ ЗАХИСНИКА ПІД ЧАС ЗАТРИМАННЯ ОСОБИ ЗА ПІДОЗРОЮ У ВЧИНЕННІ СЛУЖБОВОГО ЗЛОЧИНУ

Apprehension of a person on suspicion of committing of an official crime contains a potential threat to the law enforcement bodies of the requirements of Criminal procedural code of Ukraine in order to achieve short-term media effect in the demonstration of "effective struggle" with white-collar Crime. However, there are no procedural errors under the active position of the protection party, as a rule, offset the evidence collected in violation of the current criminal procedure legislation, which results from the adoption by the courts of Ukraine of corrective proceedings. The purpose of the article is to study procedural issues arising in connection with law enforcement agencies to detain a person suspected of committing a crime. The defender's participation in the stage of detention is important, because at this stage, a person who is potentially is suspected in the committing of official crime is especially in need of skilled legal assistance. Often, after the actual detention, questioning persons, recognitions, and on the petition of detained investigators are misled by explaining that the legal aid to the defender is granted from the moment of announcement of the detention protocol. In the context of applicable provisions of art. 208 the Criminal procedural code of Ukraine confirmed the correctness of the opinion on the wrongness of some detentores committed during the last time. In particular, there are numerous cases of detention of heads of central executive authorities (during the session of the Cabinet of Ministers of Ukraine), the deputies (during the session of the Verkhovna Rada of Ukraine or immediately after) for crimes committed by the weeks, Months, years ago. In practice, the defender does not provide access to a person who was delayed to the "crime scene" or "under the hot" and delivered to the pre-trial investigation agency, which needed immediate legal aid. The solution to this problem is seen in the rapid actions of the defender to provide the widest possible public publicity of the mentioned illegal actions of the pre-trial investigation agency. Legislative regulation requires the definition of the meaning of "an authorized service person", which has the right to conduct detention without the ruling of an investigative judge or if any. It is argued that such a category of persons should include employees of the national police, security authorities, bodies controlling adherence to tax legislation, detectives unit, internal control unit National Anti-Corruption Bureau of Ukraine, bodies of state Bureau of Investigation, bodies of State Border guard Service of Ukraine etc. An important aspect of providing legal assistance to a person arrested on suspicion of committing an official crime is the need to find out all the information about the person with the security and the circumstances of the detention: the actual time, place, or other persons who stayed with him or the grounds for detention and procedural rights have been reported, whether the video (photo-) shooting, which was seized during the detention, whether a personal search was held or any documents were selected, whether the explanations were selected or under-protective any investigative actions, etc. The decision on further procedural behaviour should be taken only after the discussion with the client of the protection position, clarification of procedural rights and art. 63 of the Constitution of Ukraine. In the event that the customer agrees to give evidence, the lawyer clarifies the procedure for questioning the suspect, his rights, to discuss the contents of the testimony, questions to be seen.

Radiographic analysis the obturation’s quality in root canal treatment performed by a South Brazilian sample of undergraduate students

ABSTRACT Objective to investigate the quality of root canal treatments performed by undergraduate students. Methods 274 root-filled teeth (excluding molars) from the Department of Endodontology of the Federal University of Santa Catarina in a nine-year period were selected and evaluated by two calibrated examiners. The evaluation was based on tooth type, number of root canals, presence or absence curvature, length of filling material considered the radiographic apex as reference (considered adequate shorter than 2mm from radiographic apex), filling material density, filling taper, and overall quality of RCT. Chi-square and Fisher exact tests were performed to analyze associations between variables of interest (p<0.05). Results 197 RCT were classified as acceptable (71.9%). The frequency of adequate RCT was significantly higher in incisor (79.4%) than in premolars (66.4%) or canines (58.1%) (p=0.015). The number of canals did not influence root canal quality in this sample (p>0.05). The factor more frequently identified as unacceptable was filling length (26.6%). All RCT performed in curved teeth and classified as unacceptable were underfilled. Procedural errors, such as perforations or instrumental separation, were not found in this sample. Conclusion The most common criteria identified as unacceptable was the length of the filling material. Incisors had better quality assessment rates than canines and premolars. The high-quality rates found in this sample may be linked to the professor/student rates.

Can the Separated Instrument be Removed From the Root Canal System out by Magnetism? A Hypothesis

Introduction: Procedural errors might occur during the treatment of the root canal system as a consequence of uncontrollable factors by the clinician. The fracture of endodontic instruments is unpleasant occurrences that happen rather frequently in the endodontic clinic. The hypothesis: As metals are magnetized to some extents, the clinicians might be able to move separated stainless steel and NiTi rotary instruments by magnets from the canals out. Evaluation of the hypothesis: The instruments (Hand Stainless Steel and Rotary NiTi) are tried to move away through using magnets at the first stage of experiment. For the next steps, the blocks and extracted natural teeth can be utilized as a situation more clinically relevant.

A Three-Dimensional Numerical Model for Predicting the Weld Bead Geometry Characteristics in Laser Overlap Welding of Low Carbon Galvanized Steel

Laser welding (LW) becomes one of the most economical high quality joining processes. LW offers the advantage of very controlled heat input resulting in low distortion and the ability to weld heat sensitive components. To exploit efficiently the benefits presented by LW, it is necessary to develop an integrated approach to identify and control the welding process variables in order to produce the desired weld characteristics without being forced to use the traditional and fastidious trial and error procedures. The paper presents a study of weld bead geometry characteristics prediction for laser overlap welding of low carbon galvanized steel using 3D numerical modelling and experimental validation. The temperature dependent material properties, metallurgical transformations and enthalpy method constitute the foundation of the proposed modelling approach. An adaptive 3D heat source is adopted to simulate both keyhole and conduction mode of the LW process. The simulations are performed using 3D finite element model on commercial software. The model is used to estimate the weld bead geometry characteristics for various LW parameters, such as laser power, welding speed and laser beam diameter. The calibration and validation of the 3D numerical model are based on experimental data achieved using a 3 kW Nd:Yag laser system, a structured experimental design and confirmed statistical analysis tools. The results reveal that the modelling approach can provide not only a consistent and accurate prediction of the weld characteristics under variable welding parameters and conditions but also a comprehensive and quantitative analysis of process parameters effects on the weld quality. The results show great concordance between predicted and measured values for weld bead geometry characteristics, such as depth of penetration, bead width at the top surface and bead width at the interface between sheets, with an average accuracy greater than 95%.

HYPOPLASIA OF THE FACIAL ARTERY SUBSTITUTED BY TRANSVERSE FACIAL ARTERY

PURPOSE. The facial artery is one of the main arteries which supply the face with blood. The different types have been researched not only for anatomical purposes but also to facilitate the different medical specialties. METHODS AND RESULTS. Our team found an unusual case of a facial artery with smaller lumen. The region, which it supplies, is partially substituted by the transverse facial artery. In the observed course the facial artery had a considerably smaller caliber than usual. After it appears on the surface of the face it divides into two untypical branches - anterior and superior. Contrariwise the transverse facial artery has a significantly bigger lumen. The separate branches, which usually originate from the facial artery, here arise from the aforementioned artery. CONCLUSIONS. These types of anatomical variations are very important for muscle and skin flaps in plastic surgery of the face. Every deviation from the normal anatomy of the main blood vessels can also lead to errors in invasive surgery procedures and medical imaging. The vascularization of the face and its variations is subject for many different disciplines.

DER RENEUAL MUSTERENTWURF FÜR EIN EU-VERWALTUNGSVERFAHRENSRECHT – HINTERGRÜNDE UND AKTUELLER STAND

The paper focuses on administrative law reform within the European Union and raises this problem in the Central Asia countries: as EU advances with its codification and structuring on the existing principles and institutions, the countries of Central Asia start from scratch. A group of academics within the Research Network on European Administrative Law (ReNEUAL), starting with comparative law method, tries to use national administrative procedural laws, case law and principles of the administrative procedure of the European and national courts, as well as the relevant soft law, especially the “Ombudsprudence” aims, taking into account new communication technologies, at developing a relevant draft law. In its independent work between 2009 to 2014 the ReNEUAL network specified the constitutional principles for administrative procedures, naming proposed draft “self-administration law”. It deals with institutions, bodies, offices and agencies of the European Union in their relations with the public as well as various cross-cutting issues: rules on the consequences of procedural errors, use of undefined legal terms, optimization of the rules for complex processes. European Parliament’s legal committee made some reference to the ReNEUAL draft and also sought advice from members of the network. Later draft from Parliament, seen as less ambitious, stays within the basis of the currently applicable EU treaties, whereby the ReNEUAL draft would sometimes require changes to the treaty. The proposed ReNEUAL builds transparent basis for exercising human and citizen rights, helps ensure transparency and consistency of the EU administrative institutions. It could also serve as a catalyst for the reform of national administrative procedural laws. The European Commission not convinced that EU administrative law could be summarized in a single legal document, asked for a cost-benefit analysis and impact assessment and publicly consulted on the codification of EU administrative procedure from 15.12.2017 to 09.03.2018, publishing results in July 2018.

Unusual anatomy of permanent maxillary and mandibular molars: Case reports

Introduction. The anatomy and morphology of the roots and root canal systems of multi-rooted teeth, especially the molars, shows numerous variations. Preoperative radiography, in particular cone-beam computed tomography (CBCT), has exceptional significance in detecting anatomical variations and unusual root canal morphologies, which are extremely important to be familiar with in order to undertake successful endodontic therapy and minimize procedural errors. Outline of cases. This report presents cases of incidental diagnosis of an unusual root anatomy and root canal morphology of permanent molars in two patients. Diagnosis in the first case was made using orthopantomography and confirmed after extraction therapy. The second case reviled unusual root anatomy and root canal morphology of the permanent molar after preoperative CBCT imaging. Conclusion. Anatomical and morphological variations of roots and root canal systems can occur in any tooth. Clinicians should expect these variations, which should be thoroughly investigated when considering dental treatment.

A prospective clinical study of the efficacy of Hyflex CM rotary instruments in an endodontics undergraduate program

Background/Aim: To investigate the incidence of procedural errors with the use of a novel nickel-titanium rotary system (Hyflex CM, Coltene/ Whaledent, Altstätten Switzerland), evaluate the technical quality of root canal treatments and assess a questionnaire completed by the participants themselves in an undergraduate dental clinic between 2014 and 2017 (Department of Endodontology, School of Dentistry, Aristotle University of Thessaloniki). Material and Methods: 118 undergraduate students in their first year of clinical practice performed a root canal treatment on a patient's molar (maxillary/mandibular). None of the participants had previous experience in rotary instrumentation. The periapical radiographs were taken with the use of the paralleling technique for standardization and were collected and evaluated by the investigator. After the root canal treatment was performed the students completed a questionnaire in order to evaluate their training on rotary instrumentation. Results: The overall incidence of instrument separation, apical perforation, root perforation, straightening and ledges was 0.8%, 4.4%, 2.3%, 5.5% and 29% respectively on root canal level. Ledges were detected more often in mandibular mesiobuccal canals. The frequency of root canals with an 'acceptable' filling was 68.4%, while overfilled and underfilled canals were found to be 8.6% and 16.2% respectively. The response rate was high (94.9%), 35% of the participants encountered no difficulty in the use of rotary instrumentation and 98.2% would use it again. Conclusions: The incidence of procedural errors was considerably low and the technical quality of the filled root canals was superior to that of similar studies. The responses of the questionnaire demonstrated a positive attitude toward rotary instrumentation.

Process-Model-Driven Guidance to Reduce Surgical Procedure Errors: An Expert Opinion

This paper explains how a detailed, precise surgical process model can help reduce errors by fostering better understanding, providing guidance during surgery, helping train newcomers, and by supporting process improvement. It describes the features that a process-modeling language should have in order to support the precise specification of such models.

Nickel-Titanium Rotary File Systems: What's New?

Ever since their introduction, nickel–titanium (NiTi) alloys have continued to revolutionize the field of endodontics. They have considerable advantages over the conventional stainless steel file in terms of mechanical properties. However, despite of their superior mechanical properties, NiTi alloys still pose some risk of fracture. Consequently, there has been considerable research conducted to investigate the mechanisms behind the occurrence of these procedural errors. Since the last decade, different proprietary processing procedures have been introduced to further improve the mechanical properties of NiTi alloys. These treatments include thermal, mechanical, electropolishing, and recently introduced electric discharge machining. The main purpose of these treatments is to impart a more martensitic phase into the files at normal body temperature, so that the maximum advantage of flexibility can be obtained. These heat-treated instruments also possess improved cyclic fatigue resistance when compared to conventional NiTi alloys. NiTi alloys can be subclassified as the instruments mainly containing austenitic phase (conventional NiTi, M-wire, R-phase), and those containing martensitic phase (controlled memory wire, ProTaper Gold, and Vortex Blue). Instruments based on austenitic alloys possess superelastic properties due to the stress-induced martensitic transformation. Contrary to this, martensitic alloys can easily be deformed due to phase transformation, and they can demonstrate the shape memory effect when heated. This review discusses the different phase transformations and heat treatments that the NiTi instruments undergo.

Automatic EKF Tuning for UAS Path Following in Turbulent Air

By using two simultaneously working Extended Kalman Filters, a procedure is implemented in order to perform in a fully autonomous way the path following in turbulent air. To guarantee the robustness of the proposed algorithm, an automatic tuning procedure is proposed to determine optimal values of Process and Measurement Noise statistics. Such a procedure is based on both the characteristics of the disturbances and the desired flight path; in particular, a specific performance index is applied to tune filters. In this way control laws are adapted to the flight condition and these lead to an optimal path-following. This research represents an upload of previous papers. It allows eliminating the time expensive trial and error procedure usually employed to tune Extended Kalman Filters. Obviously, procedure results are optimal for ever flight condition.