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Additive manufacturing of acrylonitrile butadiene styrene (ABS) was investigated based on statistical analysis via an optimization method. The present article discusses the influence of the layer thickness (LT), infill percentage (IP), and contours number (C) on the maximum failure load and elastic modulus of the final product of ABS. ABS is a low-cost manufacturing thermoplastic that can be easily fabricated, thermoformed, and machined. Chemical, stress, and creep resistance is all excellent in this thermoplastic material. ABS combines a good balance of impact, heat, chemical, and abrasion resistance with dimensional stability, tensile strength, surface hardness, rigidity, and electrical properties. To comprehend the impact of additive manufacturing parameters on the build quality, both artificial neural network (ANN) and response surface method (RSM) were used to model the data. The main characteristics of the build considered for modeling were ultimate tensile strength (UTS) and elastic modulus. Main effect plots and 3d plots were extracted from ANN and RSM models to analyze the process. The two models were compared in terms of their accuracy and capability to analyze the process. It was concluded that though ANN is more accurate in the prediction of the results, both tools can be used to model the mechanical properties of ABS formed by 3D printing. Both models yielded similar results and could effectively give the effect of each variable on the mechanical properties.

Background and Purpose: Through comparing handedness and laterality between successful athletes and ordinary people, this study endeavored to investigate the probable relationship between these two factors and skills and abilities which distinguish successful athletes from other members of the society. Procedure: The sample population in the current study included Iranian men and women who were assigned into two groups of ordinary population (group 1) and successful male and female athletes (group 2). Carter’s Laterality Inventory and The Edinburgh Handedness Inventory were employed to measure laterality and handedness, respectively. It needs to be noted that validity and reliability of Persian translation of both inventories have been proved. Following the completion of the inventories, individuals’ laterality and handedness were determined, and the data were prepared for statistical analysis. Findings: The participants included 212 individuals, out of which 135 (63.7%) were male and 77 (36.3%) were female. The individuals were compared in two groups. The first group consisted of successful athletes. Out of the 130 individuals, 45 (34/6%) were female and 85 (65/4%) were male. The second group were ordinary people from private schools in Tehran which entailed 32 (39%) women and 50 (61%) men.

Background: One of the most important challenges in dental implant placement is supporting and preserving soft tissue and bone structures. Numerous studies on fixation of soft and hard tissues at the single or double teeth site have reported immediate placement using a flapless protocol, while many studies have reported fewer results in molar extraction solutions. The current study aims to determine the clinical outcome of peri-implant soft and hard tissues following immediate implant placement. Materials & Methods: This study was conducted in the Department of Orthodontics, College of Stomatology, Xi’an Jiaotong University, Xi’an, China, from January 2021 to September 2021. In this systematic review, the search strategy was to screen electronically all relevant, authentic articles on databases of Embase, LIVIVO, EBSCO, Web of Science, LILACS, Scopus, and PubMed, published from 2011 to September 2021. Risk ratio (RR) was determined for implant failure, and mean differences (MD) were determined for soft tissue, horizontal and vertical buccal bone resorption by 95% CI, Inverse-variance, and fixed effect model or Mantel-Haenszel method between the intervention (bone substitute material) and control (no bone substitute material) groups through Stata/MP v.16. Results: Risk ratio of implant failure was similar in intervention and control group 0.02 (RR=0.02; 95%CI=-0.04 to 0.08; p=0.49). Mean differences were statistically greater in intervention than control group for soft tissue 1.65 mm (95%CI=1.05 to 2.25; p=0.00), horizontal bone resorption -0.47 mm (95%CI=-0.77 to -0.17 mm; p=0.00) and vertical buccal bone resorption -0.14 mm (95%CI=-0.24 to -0.03 mm; p=0.01). Conclusion: Our findings revealed no significant difference in implant failure between an intervention (bone substitute material) and control (no bone substitute material) groups. Mean differences were statistically greater in the intervention than the control group for soft tissue, horizontal bone resorption, and vertical buccal bone resorption. Using bone substitute material can improve long-term peri-implant soft tissue, horizontal and vertical buccal bone resorption. It is recommended to use bone-substitute material with a thin buccal plate.

In the machine learning jargon, multi-label classification refers to a task where multiple mutually non-exclusive class labels are assigned to a single instance. Generally, the lack of sufficient labeled training data demanded by a classification task is met by an approach known as semi-supervised learning. This type of learning extracts the decision rules of classification by utilizing both labeled and unlabeled data. Regarding multi-label data, however, current semi-supervised learning methods are unable to classify them accurately. Therefore, with the goal of generalizing the state-of-the-art semi-supervised approaches to multi-label data, this paper proposes a novel two-stage method for multi-label semi-supervised classification. The first stage determines the label(s) of the unlabeled training data by means of a smooth graph constructed using the manifold regularization. In the second stage, thanks to the capability of the twin support vector machine to relax the requirement that hyperplanes should be parallel in classical SVM, we employ it to establish a multi-label classifier called LP-MLTSVM. In the experiments, this classifier is applied on benchmark datasets. The simulation results substantiate that compared to the existing multi-label classification algorithms, LP-MLTSVM shows superior performance in terms of the Hamming loss, average precision, coverage, ranking loss, and one-error metrics.

This paper describes the methodology for rapid prototyping of nitinol structures by heat setting. Nitinol is a shape memory alloy commonly used in implantable medical devices. The proposed technique, based on 3D printing, can be used to effectively iterate multiple nitinol designs for different types of medical devices. We describe a rapid and low-cost process of ceramic replica molding of standard 3D printed parts to create high-temperature resistant fixtures, suitable for heat setting of nitinol. The technique represents a low cost (

Background: Lice are obligate parasites that bring about some mild infestation or severe diseases on different parts of the human body. Head lice can easily spread in an overcrowded community with inadequate hygienic conditions. Also, it affects children’s well-being and education programs. Methods: This study is a narrative review. To carry out this comprehensive research about pediculosis in Iran, all published data on scientific research resources were included i.e. Google scholar, Springer, ProQuest, JSTOR, Scopus, Web of Science, EBSCO, Bioline, BioOne, ScienceDirect, ResearchGate, PubMed, Sage, Wiley Online Library, World Scientific, and SID. Results: Overall, 52,342 students (from primary and secondary schools) and around 20,000 adult persons were infested with P. capitis in Iran during 3 decades (1990-2020) as reported by published documents but the actual number may statistically be higher. The variation of results implies that risk factors are linked with numerous cultural, geographical, economic, and personal habits. In general, the infestation rate of Pediculosis capitis in the south and southeast was higher than in other parts of Iran. Conclusion: Family members shouldavoid sharing hair tools particularly hairbrushes. Authors believe that not only economic situations but also some behaviors originating from personality traits influenced children's health. In this regard, children in higher grades might tend to conceal

Background: It has been demonstrated that pelvic floor muscles (PFMs) are involved in the pathophysiology of stress urinary incontinence (SUI). Sense of force, an aspect of proprioception, has never been evaluated in PFMs. Objectives: This study aimed to assess the proprioception of PFMs by evaluating the accuracy of force sense in adult women with SUI compared to those with continence. A further aim was to study the accuracy of force sense between various lengths and tensions of PFMs. Methods: Twenty-three women with SUI and 18 women without it were recruited in six trials with four different test conditions: 5 mm/40% (speculum opening/maximum voluntary contraction (MVC) percentage to produce), 5 mm/70%, 10 mm/40%, and 10 mm/70%. All participants were asked to reproduce the target force based on their own perceptions. The dynamometer was used to evaluate the sense of force. Results: The accuracy of force sense differed between women with SUI and those without it. In all test conditions, women with SUI had higher force reproduction accuracy. The highest amount of error was recorded at 10 mm and 40% MVC for either group. Conclusions: Women with SUI were more accurate in reproducing the target force than those with continence. Higher force sense accuracy may result from more attention to the pelvic floor area and a lack of automaticity of movements in women with SUI. Therefore, developing therapeutic management focusing on restoring automaticity seems advisable.

This paper reports on the design, fabrication, and evaluation of a novel 3D printed vacuum based soft sensor and its application as hand motion sensor. Soft sensors are an integral part of soft robotics as an emerging field of science that enables safe and easy human to machine interaction. The conventional sensors used to interface with humans in robotic systems are mechanically incompliant. Because of this mechanical compliance mismatch, these sensors cause unsafe interactions with humans. Recent advancements in 3D printing technology have allowed fabrication of complex geometries with soft polymers, perfect for more delicate and user-friendly sensors. While the existing soft pneumatic sensors work based on the positive pressure due to deformation, the proposed sensor in this work works based on vacuum due to deformation. In comparison with the similar positive pressure sensor, our vacuum-based sensor is much softer and has minimum interference with hand motion. Finite element analysis (FEA) is used to analyze the design. Also, a kinematic model of the hand is developed using Matlab to visualize the hand motion based on the sensor data. This could show the potential application of the soft hand motion sensor in virtual reality and telehealth.

This study presents the design, development, and experimental testing of a single piece designed compliant gripper manipulated by a 3 DOF soft robot. The manipulator consists of two soft links. While the bottom arm is 2 DOF and is tendon driven by two servo motors, the SDOF upper arm is also tendon driven by a servo motor. The two-finger-designed compliant gripper is also actuated by a servo motor. The base of the robot holds the motors and the soft manipulator. The MATLAB Simscape model of the robot is created to perform deformation and motion analysis of the gripper and soft manipulator. The cad model of the robot is imported, and the manipulator parts are converted into soft links using discrete beam elements. The large deflecting hinges on the compliant grippers are also transformed to mimic the physical gripper. Since the soft manipulator and the compliant gripper were designed monolithically, the robot was 3D printed as a single piece using thermoplastic polyurethane (TPU). The gripper is tested for its grasping and lifting performance while recording the applied forces by the gripper using a Flex sensor. Using the opencv tool for image processing and object analysis, we used a dual-camera setup with a known environment to add intelligence to the robot. Since the manipulator is designed as soft, the gripper can reach any position within its working space with any orientation.

Despite the advantages and superiorities of compliant mechanisms and soft robots over rigid mechanisms, optimizing the stiffness of flexible links and dynamic properties of complex and high mobility designs is increasingly challenging. Additionally, the largest challenge in the design and modeling of such systems is understanding the deformation of the two bodies when connected along with their interaction in complex cases such as large deflecting buckling beams, especially for people who are new in the area. There exist several methods and techniques for obtaining kinematic relations as pseudo rigid body modeling (PRBM), first and second kind of Elliptica theory, discrete beam element method for simple geometries of compliant mechanisms, and nonlinear dynamical modeling of soft robots assuming using constant curvature spatial curves, and also machine learning. To address this issue, we present the user-friendly and open-access MATLAB Toolbox for the design and motion analysis of compliant mechanisms and soft robots. The developed toolbox serves as a platform to visualize the deformation of compliant joints and compliant beams (Module 1), visualize the displacement of various compliant mechanisms (Module 2), design simple and complex compliant mechanisms using the hinges and beams, and design and motion analysis of soft robots (Module 3).

Among the robotic systems, biomimetic robots performing fish-like locomotion have been the focus of much attention recently as there are many applications for swimming robots, including monitoring of underwater environments, detection of pollution, and disaster relief. This study presents the design and development of a biomimetic fish-like robot based on real carp locomotion. The robot has five main body parts including the head, soft neck, hinged body, compliant tail, and caudal fin. The head houses three ultrasonic sensors to guide the robot while connected to the body through two degrees of freedom (DOF) soft link resembling the neck vertebrate. The 2 DOF soft link enables the head to bend up, down, left, and right which is essential for controlling the soft robot’s direction. The body is connected to the soft tail using a quick return crank mechanism to actuate the tail. The tail integrates a soft tail and a rigid caudal fin. While all parts of the soft fish-like robot are 3D printed using polylactic acid (PLA), thermoplastic polyurethane (TPU), the mold is made from silicone rubber to waterproof. The ultrasonic sensors are utilized to detect obstacles so that the robot may maneuver around. The swimming pattern only for two-dimensional motion is tested in the air and underwater. According to the experimental results, the proposed robot better imitates the fish through its soft 2 DOF link and tail.

Soft parallel robots are among the latest advancements in the field of soft robotics with wide range of applications. Most of the existing soft robotic systems comprise from serial soft arms which can provide high degrees of freedom (DOF), but suffer from low stiffness, and limited payload due to their soft structure. To address these issues recently researchers have introduced soft parallel robots. Similar to their rigid counterparts, soft parallel robot will have higher blocking force, stiffness, and accuracy. We have previously introduced two, and three DOF soft parallel robots and in the current work we will introduce a novel six DOF robot named 3-universal-spherical-revolute (3USR) soft parallel robot. This robotic system is consisted of three closed-loop kinematic chains. Each chain includes a soft active arm with two DOF which is connected to a compliant passive link through soft joints. This configuration provides six DOF for the soft robot (x, y, z, roll, pitch, yaw). The prototype of the robot is 3D printed using NINJA flex, thermoplastic polyurethane (TPU), and polylactic acid (PLA). Each soft active arm consists of a two DOF tendon driven soft actuator which is 3D printed using NINJA flex and are actuated using two servo motors. Two types of soft joints are used namely soft spherical and revolute joints. The shape and size of the soft joints are optimized so that the robot will achieve six DOF. MATLAB Simscape model is used to simulate the dynamical response of the mechanism for various inputs.

The present study provides a systematic method for assessing the efficiency and soundness of banks. The analysis is based on a set of benchmarks related to the financial performance of banks. In this regard, this research has explored a model for evaluating accepted banks in Tehran Stock Exchange using the data envelopment analysis method. One of the most important applications of this technique is measuring the efficiency of bank branches. In addition, paying special attention to the health of the banking system corresponds to the health of the society’s economics. It is essential to implement precise analysis benchmarks to evaluate banks and other financial institutions due to their importance in the economics. One of these benchmarks is efficiency. In this study, 18 Iranian business banks have been analysed using data envelopment analysis on the basis of financial ratios. Also, their efficiency has been computed using the output-based CCR envelopment model, assuming a constant efficiency-scale ratio. The results suggest that Gardeshgari bank has been selected as the most efficient and healthy bank between 2011 and 2015 on the basis of financial and non-financial criteria, and using the trapezoidal fuzzy number method.

Background. The present study evaluated the antimicrobial efficacy of composite resins containing nano-silver (NAg) particles used in fixed orthodontic retainers. Methods. Nano-composite resin samples with 1%, 2%, and 5% concentrations of NAg were prepared. The antimicrobial effectiveness of NAg was assessed against Streptococcus mutans, Streptococcus sanguis, and Lactobacillus acidophilus by the biofilm inhibition test (three-day-old biofilms), eluted components test (on days 3, 15, and 30), and disk-diffusion agar test after 48 hours. Measures of central tendency and index of dispersion were used to determine colony-forming units. Kruskal-Wallis test and Mann-Whitney U test were also used. Results. The biofilm inhibition test showed a significant decrease in the colonies of S. mutans (87.64%, 96.47%, and 99.76% decrease), S. sanguis (98.13%, 99.47%, and 99.93% decrease), and L. acidophilus (81.59%, 90.90%, and 99.61% decrease) at 1%, 2%, and 5% concentrations of Nag, respectively, compared to the control groups. The colony-forming unit (CFU)/mL of tested microorganisms continuously decreased with increased NAg concentration. In the eluted component test, no significant differences were noted in the 3rd, 15th, and 30th days between the different concentrations of Nag-containing composite resin disks and control samples. According to the disk-diffusion agar test, there was no growth inhibition zone for the composite resin disks containing 1% and 2% concentrations of Nag. However, the growth inhibition zone was seen with a 5% concentration, with a diameter of 9.5±0.71 mm for S. mutans, 8.5±0.71 mm for S. sanguis, and 8±1.41 for L. acidophilus. Conclusion. The incorporation of NAg into composite resins has antibacterial effects, possibly preventing dental caries around fixed orthodontic retainers.

Context: With a key role in normal shoulder function, scapular kinematics have been investigated in shoulder impingement syndrome (SIS). Objectives: This systematic review aimed at determining scapular kinematic patterns in patients with SIS compared to in asymptomatic individuals. Data Sources: Databases such as PubMed, Scopus, Web of Science, Ovid, Embase and PEDRO were searched from January 1995 to June 2021. Study Selection: Articles in English published in peer-reviewed journals and using motion analysis systems to compare scapular kinematics between patients with SIS and asymptomatic subjects during arm elevation were included. Data Extraction: A modified Downs and Black checklist was used to assess the risk of bias of the included studies. A random-effects model was employed to perform a meta-analysis. Results: Nine out of 1650 screened abstracts were included for data extraction. Scapular upward rotation significantly decreased during arm elevation in SIS (SMD = -0.13, 95% CI = -0.23 to -0.02) with a low effect size (I2 = 46%). No differences were observed in scapular posterior tilt (SMD = -0.07, 95% CI = -0.18 to 0.03) and external rotation (SMD = 0.02, 95% CI = -0.06 to 0.09) between patients with SIS and asymptomatic subjects. Conclusions: This review revealed that except for scapular upward rotation, scapular movement was generally insignificantly different between the subjects with and without SIS during arm elevation. Between-group differences might have been overlooked as a result of the high risk of bias in the included studies. The high-quality studies addressing confounders are required to provide a definitive conclusion on the relationship between SIS and scapular kinematics.