Nonlinear control of wheeled mobile robots

The purpose of this project is to implement an autonomous navigation system using nonlinear control techniques to control a wheeled mobile robot (WMR) to follow a preplanned trajectory and track a path. Two other aspects of navigation are studied: path planning and obstacle avoidance. Those three aspects are integrated into a navigation strategy that manages navigation and prevents deadlocks. Two nonlinear control techniques for path tracking and trajectory following have been developed and implemented. In the first approach, a fuzzy logic controller is used to drive the robot through a set of waypoints leading to the destination. In another approach, a controller derived from a Lyapunov function is used to track a reference trajectory that is time dependent. For path planning, a novel optimization technique based on dynamic programming has been developed. The curvature velocity method has been used for obstacle avoidance. The testing was conducted on a P3-AT all-terrain mobile robot equipped with encoders, a gyroscope, and sonar sensors for localization and environment perception. The test results validate the effectiveness of the different approaches that have been developed

Immediate implant placement by using natural bovine bone substitute and acellular collagen matrix

Adequate bone and soft tissue volume is important to allow proper implants osseointegration, survival and esthetic result. The aim of this case report was to observe an immediate implant placement by using natural bovine bone substitute and acellular collagen matrix to gain better soft tissue result. Upon screw-retained provisional bridge removal after four months, a successful peri-implant soft tissue healing was observed. Then one year after final bridge, a stable soft and hard tissue situation, as well as sufficient implant stability, granules osteointegration into newly formed bone was recorded

Immediate implant placement by using natural bovine bone substitute with hyaluronate

Sufficient bone volume is important to allow proper implants osseointegration. The aim of this case report was to observe an immediate implant placement by using xenograft granules with hyaluronate and without any membrane coverage. The augmentation areas were assessed 3 months later during final crown installation and after 1 year and 6 months of implant loading. Satisfactory implant stability, granules osteointegration into newly formed bone, as well as stable soft tissue supported by the granules were observed

Analysis of changes in gingiva-occlusal parameters as perceived by three Middle-East population.

Purpose. This study aims to compare the effect of various smile parameters (buccal corridor, gummy smile, midline to face discrepancy, with and without upper lip filling) on the perception of smile attractiveness by applying the digital modification of images judged by laypersons from different Middle East populations. Materials and Methods. One hundred and eighty participants are divided into 3 groups (n=60: 30 men and 30 women): Lebanese, Syrian, and Egyptian laypersons. A frontal photo of a woman\u27s smile is manipulated with Photoshop to modify each smile parameter gradually into 3 grades. The total number of smiles assessed is 18. In addition, each evaluator must indicate which feature she or he finds most attractive in a face. Analysis of repeated measures variances followed by univariate analyses and multiple comparisons of Bonferroni are performed. Results: Eyes and smile are the most attractive elements in the face. For midline to face discrepancy, only Lebanese laypeople and Egyptian women prefer the coincidence of the midline to face compared with other positions with significant difference (p value 0.05). Concerning the buccal corridor, its size does not influence smile attractive (p value\u3e 0.05). Upper lip filling affected the perception of smile aesthetics for the midline (for Syrians and Egyptians). Conclusion: Sex and culture affect the perception of the smile attractiveness for certain parameters. Alteration of the buccal corridor does not seem to influence the smile attractiveness. Upper lip filling may be advantageous in some cases and unfavorable in others. Clinical significance: Dentists should take into consideration cultural differences when restoring smile aesthetics

An Improved Earned Value Analysis Tool for Mitigating Progress Risks in Long Duration Projects

As a risk control tool, earned value analysis is crucial for identifying risky trends in the budget or schedule of a project. This tool relies on earned value management, a method for calculating cost and schedule variances. However, this method does not take into account the time value of money. This in itself is a threat that could lead to misleading data and eventually wrong decisions. This paper explores the risk management process, the earned value management method, and proposes a methodology that compliments the earned value management method with net present value calculations. This will allow project managers to take sound decisions based on more accurate information

Detection and Automated Scoring of Dicentric Chromosomes in Nonstimulated Lymphocyte Prematurely Condensed Chromosomes After Telomere and Centromere Staining

PurposeTo combine telomere and centromere (TC) staining of premature chromosome condensation (PCC) fusions to identify dicentrics, centric rings, and acentric chromosomes, making possible the realization of a dose–response curve and automation of the process.Methods and MaterialsBlood samples from healthy donors were exposed to 60Co irradiation at varying doses up to 8 Gy, followed by a repair period of 8 hours. Premature chromosome condensation fusions were carried out, and TC staining using peptide nucleic acid probes was performed. Chromosomal aberration (CA) scoring was carried out manually and automatically using PCC-TCScore software, developed in our laboratory.ResultsWe successfully optimized the hybridization conditions and image capture parameters, to increase the sensitivity and effectiveness of CA scoring. Dicentrics, centric rings, and acentric chromosomes were rapidly and accurately detected, leading to a linear-quadratic dose–response curve by manual scoring at up to 8 Gy. Using PCC-TCScore software for automatic scoring, we were able to detect 95% of dicentrics and centric rings.ConclusionThe introduction of TC staining to the PCC fusion technique has made possible the rapid scoring of unstable CAs, including dicentrics, with a level of accuracy and ease not previously possible. This new approach can be used for biological dosimetry in radiation emergency medicine, where the rapid and accurate detection of dicentrics is a high priority using automated scoring. Because there is no culture time, this new approach can also be used for the follow-up of patients treated by genotoxic therapy, creating the possibility to perform the estimation of induced chromosomal aberrations immediately after the blood draw

Quantitative Measurements of the Depth of Enamel Demineralization before and after Bleach: An In Vitro Study

Objective. This study is aimed at determining two main points. First, if the Canary System™ (CS), initially used to assess caries, can measure a decalcification depth of bleached enamel quantitatively, and second, whether or not whitening has a harmful effect on enamel. This device can be considered a useful tool in the clinical assessment of the progression of demineralization after bleaching. Materials and Methods. This study collected sixty human premolars that are in a good state recently extracted for orthodontic reason. To properly disinfect and preserve the premolars, they were stored in a saline solution and later in distilled water for a period of two weeks to allow the premolars to rehydrate. Later, 24 hours before the experiment, the premolars were introduced into a solution of artificial saliva to acquire back their minerals. The mineral content of the teeth was measured by the Canary System™ before bleaching. The teeth were bleached with 30% hydrogen peroxide (fläsh HP 30%), 30 min per week and for 3 consecutive weeks to simulate the conditions of strong bleaching in the clinic. The extent of demineralized enamel was measured by the Canary System™ at three points on the enamel surface of each tooth. The data were averaged for each application of the bleaching product. The demineralization extent of the teeth was measured by the Canary System™ before and after bleaching. The significance level was set at 0.05, and SPSS version 26 was used. The data were analyzed by using Wilcoxon’s and Student’s tests. Results. Mineral loss occurred after the first bleaching session; the Canary System™ detected a decalcification in the first bleaching session ( μm) compared to the other sessions (), while no significant change was detected between the second and the third sessions (). Conclusion. Based on the findings of the present study, under in vitro conditions, it was possible to measure the demineralization extent of bleached enamel with the Canary System™

In vitro evaluation of the color stability and surface roughness of a new composite flow

The aim of this study was to evaluate the color stability and the surface roughness of a bulk-fill composite flow (SDR® Plus) by comparison to an ORMOCER-based composite (Ceram.x® Universal SphereTEC?) in order to confirm the validity of using SDR® Plus

Dentinal Hypersensitivity Treatment Using Diode Laser 980 nm: In Vivo Study

peer reviewedThe discomfort of patients due to dentinal hypersensitivity (DH) is one of the main challenges that dentists face in daily practice. Difficulties in DH treatment gave rise to many protocols which are currently used. The aim of this clinical study is to evaluate the effectiveness of a new protocol on the reduction of dentinal hypersensitivity with diode laser 980 nm and the application of a graphite paste. 184 patients enrolled in the study, the degree of pain was evaluated by visual analog scale (VAS), graphite paste was applied on the exposed dentine before irradiation, the application of diode laser 980 nm with continuous mode, backward motion, tangential incidence of the beam in non-contact mode and a delivery output of 1 W. Fiber’s diameter was 320 μm and total exposure time depended on the time necessary to remove the graphite paste from the teeth. Statistical analyses were performed with Prism 5® software. Pain in post-operative significantly decreased immediately after the treatment. Mean values stayed stable until a 6-month follow-up. The application is considered to be safe with long-term effectiveness

Advances in Electronic-Nose Technologies Developed for Biomedical Applications

The research and development of new electronic-nose applications in the biomedical field has accelerated at a phenomenal rate over the past 25 years. Many innovative e-nose technologies have provided solutions and applications to a wide variety of complex biomedical and healthcare problems. The purposes of this review are to present a comprehensive analysis of past and recent biomedical research findings and developments of electronic-nose sensor technologies, and to identify current and future potential e-nose applications that will continue to advance the effectiveness and efficiency of biomedical treatments and healthcare services for many years. An abundance of electronic-nose applications has been developed for a variety of healthcare sectors including diagnostics, immunology, pathology, patient recovery, pharmacology, physical therapy, physiology, preventative medicine, remote healthcare, and wound and graft healing. Specific biomedical e-nose applications range from uses in biochemical testing, blood-compatibility evaluations, disease diagnoses, and drug delivery to monitoring of metabolic levels, organ dysfunctions, and patient conditions through telemedicine. This paper summarizes the major electronic-nose technologies developed for healthcare and biomedical applications since the late 1980s when electronic aroma detection technologies were first recognized to be potentially useful in providing effective solutions to problems in the healthcare industry