Current Status and Future Trends of Acceptance and Commitment Therapy (ACT) for Smoking Cessation: A Narrative Review with Specific Attention to Technology-Based Interventions.

Background: During recent decades, it has become evident that cigarette smoking has led to an increase in cancer, risk of death, and economic problems or sanitation issues worldwide. Acceptance and commitment therapy (ACT), as a third-wave behavioral therapy, has devoted significant attention to smoking cessation. However, this treatment has been utilized in different formats and protocols. Moreover, addressing its challenges and progress needs examination and integration. Accordingly, the primary aim of this study was to present a narrative review for summarizing and integrating the current data on the effectiveness of ACT on smoking cessation. This study also aimed to investigate the challenges and the future of this field. Methods: The publications from January 1, 2010 to October 9, 2021 were identified by searching MEDLINE, Embase, Scopus, PsycINFO, and Web of Science electronic databases. The search was performed with the following keywords: "Acceptance AND Commitment Therapy" OR "Acceptance" AND "smoking" OR "tobacco" OR "cigarette" OR "smoker" OR "Nicotine". The inclusion criterion was studies with interventions aimed at reducing smoking cessation in smokers. Findings: A total of 17 articles were analyzed in this study. The results showed that this treatment has significant effectiveness in smoking cessation and psychiatric comorbidities. Moreover, the role of experiential avoidance in smoking cessation was discussed in detail. Conclusion: ACT is a suitable psychotherapy module for smoking cessation. However, it needs some upgrades regarding technology. To this end, smartphone applications and AVATAR therapy technologies were discussed with their advantages and solvable disadvantages.

The effect of orthopedic screw profiles on the healing time of femoral neck fracture.

One possible treatment for femoral neck fractures, especially in young people, is the use of bone screws or Lug screws. The design of these implants requires taking into account the biocompatibility of materials, mechanical properties plus surface properties, and thread's geometric, as well as chemical properties, etc. Various profiles are designed for fracture fixation. The most famous of these profiles, which are introduced by the ISO standard, are HB, HC, and HD type profiles. This article investigates the performance of these profiles in reducing or increasing the healing time. This study is based on the rule of bone remodeling and using a set of three-dimensional computational (finite element) models. The study revealed that the HB profile outperformed the other two profiles. Meanwhile, HD profile was also better than HC profile.

Dynamic analysis of varus knee using a subject-specific multibody model of the knee before and after osteotomy.

Varus misalignment of the hip-knee-ankle angle causes greater loads on the medial compartment of the knee and increases the risk of developing knee osteoarthritis. High tibial osteotomy is a surgical method where the load-bearing axis is shifted laterally. The purpose of this study is to define a subject-specific three-dimensional multibody model of the knee to investigate the effect of osteotomy on cartilages and menisci during the stance phase of gait. It is assumed that osteotomy transfers load-bearing to the lateral parts of the knee. Magnetic resonance images of a patient with varus alignment were used to generate the geometries of the bones, cartilages, and menisci. Then, an experimental approach was used to determine the parameters for the stiffness matrices and compliant contact models of the tibio-menisco-femoral articulations with the use of finite element solutions. As indicated by the research findings, the contact force at the medial cartilage decreased as the load-bearing axis was transferred to the lateral parts. This subject-specific noninvasive analysis of contact force can be considered as a preoperative assessment tool for the surgeon. to predict the effects of high tibial osteotomy and the shifting of the load-bearing axis to the soft tissues of the knee.

A Novel Optimization Framework to Improve the Computational Cost of Muscle Activation Prediction for a Neuromusculoskeletal System.

The high computational cost (CC) of neuromusculoskeletal modeling is usually considered a serious barrier in clinical applications. Different approaches have been developed to lessen CC and amplify the accuracy of muscle activation prediction based on forward and inverse analyses by applying different optimization algorithms. This study is aimed at proposing two novel approaches, inverse muscular dynamics with inequality constraints (IMDIC) and inverse-forward muscular dynamics with inequality constraints (IFMDIC), not only to reduce CC but also to amend the computational errors compared to the well-known approach of extended inverse dynamics (EID). To do that, the equality constraints of optimization problem, which are computationally tough to satisfy, are replaced by inequality constraints, which are easier to satisfy. To verify the practical application of the proposed approaches, the muscle activations of the lower limbs during the half of a gait cycle are quantified. The simulation results of the optimal muscle activations are then compared to the experimental ones. The results reveal that IMDIC requires less CC (87.5%) compared to EID. In addition, CC of IMDIC was about 33.3% improved by the application of IFMDIC. The findings of this study suggest that although the novel approach of IFMDIC decreases CC compared to IMDIC, the convergence of its results is very sensitive to the primary guess of the optimization variables.

Biomechanics of the Healthy and Keratoconic Corneas: A Combination of the Clinical Data, Finite Element Analysis, and Artificial Neural Network.

BACKGROUND: Keratoconus is recognized by asymmetrical thinning and bulging of the cornea, resulting in distortion in the surface of the cornea. Keratoconus also alters the biomechanical properties of the cornea, which can be an indicator of the healthy and keratoconus eyes. This study was aimed at employing a combination of clinical data, finite element method (FEM), and artificial neural network (ANN) to establish a novel biomechanical- based diagnostic method for the keratoconus eyes. METHODS: To do that, the clinical-biomechanical parameters of 40 healthy and 40 keratoconus eyes were obtained via the Pentacam and non-contact tonometer (Corvis ST, Oculus Optikgeräte, Wetzlar, Germany) devices. Intraocular pressure (IOP) was measured using a Goldmann applanation tonometer as well as Corvis. According to the geometry of the cornea, the FE model of each cornea was made and the same boundary and loading conditions were applied not only to confirm the FE model in terms of the biomechanical parameters but also to calculate the amount of von Mises stress in the apex of the cornea. The clinical-biomechanical data of the Corvis along with the von Mises stresses were then incorporated into the ANN algorithm to distinguish the healthy and keratoconus corneas on a basis of the resulted von Mises stresses. The proposed programming code, according to the input data from the Corvis, enabled to predict whether the cornea is keratoconus or not. Finally, to verify the results of the proposed method, 155 individuals were examined. RESULTS: The clinical and biomechanical results of the Corvis revealed that the healthy corneas have a higher thickness compared to the keratoconus ones. No significant differences were observed among the IOPs, 1st applanation length, and pick distance in the highest concavity. The 2nd applanation length and radius in the highest concavity of the healthy cornea were higher than the keratoconus ones. Conversely, the 1st and 2nd applanation velocities and deformation amplitudes of the keratoconus corneas were higher than the healthy ones. The FE results also showed higher stresses for the healthy corneas compared to the keratoconus ones. The ANN was also well verified since it demonstrated more than 95.5% accuracy on diagnosing the keratoconus eyes. CONCLUSION: These findings have implications not only for identifying the keratoconus corneas as an important clinical and surgical tool for eye care professionals but also for providing both a quantitative and an accurate approach to the problem of understanding the biomechanical nature of keratoconus.

Physical Properties, Cytocompatibility and Sealability of HealApex (a Novel Premixed Biosealer).

INTRODUCTION: The objective of this study was to evaluate the physical properties, cytotoxicity and sealing ability of HealApex _a new premixed calcium-silicate-phosphate-based biosealer_ in comparison with AH-26. METHODS AND MATERIALS: Setting time, working time, film thickness, flow and radiopacity evaluation were performed according to ISO 6876 specification. L929 fibroblasts were incubated with the extracts of sealers and cytotoxicity was then evaluated using MTT assay. Thirty intact extracted human premolars were instrumented using step-back technique. The specimens were obturated with gutta-percha and experimental sealers employing lateral condensation technique. Sealing ability of sealers was investigated for up to one month using fluid filtration method. Data were statistically analyzed by t-test and ANOVA. RESULTS: Physical properties of both sealers conformed to ISO specification. AH-26 exhibited significantly higher flow, higher radiopacity and lower film thickness; whereas HealApex showed lower setting time (P<0.05). HealApex represented high cell viability (P<0.05); however, AH-26 demonstrated significantly lower cell viability compared with the negative control group (P<0.05). There was no significant difference in microleakage between the sealers after 1 and 7 days; however, after 30 days, HealApex displayed better sealing ability (P<0.05). CONCLUSIONS: In this in vitro study, HealApex revealed acceptable physical properties, biocompatibility and good sealing ability as an endodontic sealer. Obtained results showed the new sealer had acceptable physical properties and good biocompatibility. In short term, the sealing ability of HealApex was comparable with AH-26 whilst in long term, HealApex's sealing ability was better than the epoxy resin-based sealer.

A non-invasive measurement of the knee contact force using a subject-specific musculoskeletal model to investigate osteotomy.

The varus knee has been defined as a Hip-Knee-Ankle alignment of less than 180 degrees. Varus knee alignment increases the load on the medial knee and also the risk of osteoarthritis. High tibial osteotomy has been designed to modify the malalignment of varus knee. The aim of this study was to investigate the osteotomy effects on knee adduction moment (KAM) and contact forces using a musculoskeletal and subject-specific knee model. A patient with varus knee and no symptoms of any other disease or disability participated in this study. The geometry of the multibody knee model has been modified using MR images. The solutions of its finite element model have been used to determine the parameters of the multibody model. The motion data, ground reaction force and kinetic data have been applied to run the subject-specific musculoskeletal model during the stance phase of gait. After osteotomy, the adduction moment decreased, where the maximum values are comparable to other studies. The pattern of KAM did not witness any significant changes. The total and medial contact forces reduced considerably after surgery, but the lateral contact force did not significantly change. The changes in total and medial contact forces and lack of change in lateral contact force could be explained by modification of the gait pattern after surgery.

Prediction of human gait trajectories during the SSP using a neuromusculoskeletal modeling: A challenge for parametric optimization.

The parametric optimization techniques have been widely employed to predict human gait trajectories; however, their applications to reveal the other aspects of gait are questionable. The aim of this study is to investigate whether or not the gait prediction model is able to justify the movement trajectories for the higher average velocities. A planar, seven-segment model with sixteen muscle groups was used to represent human neuro-musculoskeletal dynamics. At first, the joint angles, ground reaction forces (GRFs) and muscle activations were predicted and validated for normal average velocity (1.55 m/s) in the single support phase (SSP) by minimizing energy expenditure, which is subject to the non-linear constraints of the gait. The unconstrained system dynamics of extended inverse dynamics (USDEID) approach was used to estimate muscle activations. Then by scaling time and applying the same procedure, the movement trajectories were predicted for higher average velocities (from 2.07 m/s to 4.07 m/s) and compared to the pattern of movement with fast walking speed. The comparison indicated a high level of compatibility between the experimental and predicted results, except for the vertical position of the center of gravity (COG). It was concluded that the gait prediction model can be effectively used to predict gait trajectories for higher average velocities.

Effects of external loading on lumbar extension moment during squat lifting.

OBJECTIVES: The main objective of this study has been qualitative investigation of the effects of external loading on the lumbar extension moment during squat lifting. Findings of this study may allow to determine the factor with the most considerable effect on the lumbar extension moment and may help determine the lumbar spine risk factors at temporo-spatial coordination during squat lifting. MATERIAL AND METHODS: Twelve healthy men volunteered to perform slow and fast squat lifting of a box of varied mass (4 kg, 8 kg and 12 kg). The eight-channel electromyography was applied to detect the activities of abdominal (rectus abdominis and external oblique) and lower back muscles (iliocostalis lumborum and multifidus). The lumbar extension moment was calculated using 3D linked segment model. Ground reaction forces and kinematic data were recorded using a Vicon system with 2 parallel Kistler force-plates. RESULTS: Significant increases (both p-values < 0.05) were detected for the peak lumbar extension moment with increases in the lift speed and box weight. Moreover, a significant interaction (p = 0) was detected between the lift speed and box weight. Furthermore, insignificant differences (all p-values > 0.05) were detected between the lumbar angles related to the lower trunk muscles peak activities and lumbar angle related to the peak lumbar extension moment in most of the lifts. CONCLUSIONS: According to the findings, the inertial force of the lifted box is the most important factor that affects the lumbar extension moment during squat lifting. Moreover, critical lumbar angles are seemingly those ones in which the lifted box reaches the peak acceleration. Int J Occup Med Environ Health 2017;30(4):665-679.

Review on different experimental techniques developed for recording force-deformation behaviour of soft tissues; with a view to surgery simulation applications.

Different experimental techniques which have been developed to obtain data related to force-deformation behaviour of soft tissues play an important role in realistically simulating surgery processes as well as medical diagnoses and minimally invasive procedures. Indeed, an adequate quantitative description of soft-tissue-mechanical-behaviour requires high-quality experimental data to be obtained and analysed. In this review article we will first scan the motivations and basic technical issues on surgery simulation. Then, we will concentrate on different experimental techniques developed for recording force-deformation (stress-strain) behaviour of soft tissues with focussing on the in-vivo experimental setups. We will thoroughly review the available techniques by classifying them to four groups; elastography, indentation, aspiration and grasping techniques. The evolutions, advantages and limitations of each technique will be presented by a historical review. At the end, a discussion is given with the aim of summarising the proposed points and predicting the future of techniques utilised in extracting data related to force-deformation behaviour.

A general-purpose framework to simulate musculoskeletal system of human body: using a motion tracking approach.

Computation of muscle force patterns that produce specified movements of muscle-actuated dynamic models is an important and challenging problem. This problem is an undetermined one, and then a proper optimization is required to calculate muscle forces. The purpose of this paper is to develop a general model for calculating all muscle activation and force patterns in an arbitrary human body movement. For this aim, the equations of a multibody system forward dynamics, which is considered for skeletal system of the human body model, is derived using Lagrange-Euler formulation. Next, muscle contraction dynamics is added to this model and forward dynamics of an arbitrary musculoskeletal system is obtained. For optimization purpose, the obtained model is used in computed muscle control algorithm, and a closed-loop system for tracking desired motions is derived. Finally, a popular sport exercise, biceps curl, is simulated by using this algorithm and the validity of the obtained results is evaluated via EMG signals.

Atomic force microscope-based single cell force spectroscopy of breast cancer cell lines: an approach for evaluating cellular invasion.

The adhesiveness of cancerous cells to their neighboring cells significantly contributes to tumor progression and metastasis. The single-cell force spectroscopy (SCFS) approach was implemented to survey the cell-cell adhesion force between cancerous cells in three cancerous breast cell lines (MCF-7, T47D, and MDA-MB-231). The gene expression levels of two dominant cell adhesion markers (E-cadherin and N-cadherin) were quantified by real-time PCR. Additionally, the local stiffness of the cell bodies was measured by atomic force microscopy (AFM), and the actin cytoskeletal organization was examined by confocal microscopy. Results indicated that the adhesion force between cells was conversely correlated with their invasion potential. The highest adhesion force was observed in the MCF-7 cells. A reduction in cell-cell adhesion, which is required for the detachment of cells from the main tumor during metastasis, is partly due to the loss of E-cadherin expression and the enhanced expression of N-cadherins. The reduced adhesion was accompanied by the softening of cells, as described by the rearrangement of actin filaments through confocal microscopy observations. The softening of the cell body and the reduced cellular adhesiveness are two adaptive mechanisms through which malignant cells achieve the increased deformability, motility, and strong metastasis potential necessary for passage through endothelial junctions and positioning in host tissue. This study presented application of SCFS to survey cell phenotype transformation during cancer progression. The results can be implemented as a platform for further investigations that target the manipulation of cellular adhesiveness and stiffness as a therapeutic choice.

Evaluation of mechanical properties of human mesenchymal stem cells during differentiation to smooth muscle cells.

Human mesenchymal stem cells (hMSCs) are multipotent cells appropriate for a variety of tissue engineering and cell therapy applications. Mechanical properties of hMSCs during differentiation are associated with their particular metabolic activity and regulate cell function due to alternations in cytoskeleton and structural elements. The objective of this study is to evaluate elastic and viscoelastic properties of hMSCs during long term cultivation in control and transforming growth factor-ß1 treatment groups using micropipette aspiration technique. The mean Young's modulus (E) of the control samples remained nearly unchanged during 6 days of cultivation, but that of the test samples showed an initial reduction compared to its relevant control sample after 2 days of treatment by biological growth factor, followed by a significant rise after 4 and 6 days. The viscoelastic creep tests showed that both instantaneous and equilibrium moduli significantly increased with the treatment time and reached to maximum values of 622.9 ± 114.2 and 144.3 ± 11.6 Pa at the sixth day, respectively, while increase in apparent viscosity was not statistically significant. Such change of mechanical properties of hMSCs during specific lineage commitment contributes to regenerative medicine as well as stem-cell-based therapy in which biophysical signals regulate stem cell fate.

Ankle rotation changes and its influences in knee osteoarthritis.

BACKGROUND: Biomechanical factors are known to be important in knee osteoarthritis (OA) development and progression. This study was designed to determine changes of hamstrings muscle activation, knee adduction moment and ankle rotation angle in two knee osteoarthritis (mild and moderate) and a healthy control group. METHODS: 16 females (10 with mild and 6 with moderate medial knee osteoarthritis) and 10 control matched females were recruited. A 3D gait analysis was performed on the subjects while they walked along the walkway. Electromyography data was also collected during gait from lateral and medial hamstrings. Post Hoc Tukey HSD (multi comparison) was performed to compare knee adduction moment, ankle rotation angle and medial and lateral hamstrings activity at early and late stance, between three groups. RESULTS: Ankle rotation angle, knee adduction moment and lateral hamstrings activation showed no significant difference between three groups. Interestingly, medial hamstrings activity was significantly higher at late stance in moderate group compared with asymptomatic and mild groups (p=0.03, 0.02 respectively). Also knee adduction moment at late stance was significantly and directly correlated with ankle rotation angle, and lateral hamstrings activity at early stance was significantly and inversely correlated with this angle. CONCLUSIONS: It can be concluded that, increased lateral hamstrings activity can increase external ankle rotation and consequently decrease knee adduction moment.

Differences in center of pressure trajectory between normal and steppage gait.

BACKGROUND: This pilot study aimed to assess the differences in center of pressure trajectory in neuropathic patients with steppage gait. Steppage gait has previously been evaluated by several biomechanical methods, but plantar pressure distribution has been much less studied. The purpose of this study was to analyze the changes in center of pressure trajectory using a force plate. METHODS: The steppage gait group was selected from the patients using drop foot brace (25 male) and the control group was selected from Isfahan university students (20 male). They walked at self- selected speed at a mean of ten trials (+2) to collect the center of pressure using a force plate. Center of pressure patterns were categorized into four patterns based on the center of pressure displacement magnitude (spatial features) through time (temporal features) when the longitudinal axis of the insole was plotted as the Y- axis and the transverse axis of the insole as X- axis during stance phase. RESULTS: The horizontal angle measured from center of pressure linear regression was positive in the control group (4.6 ± 2.4) (p < 0.005), but negative in the patient group (- 2.3 ± 1.6) (p < 0.005). CONCLUSIONS: The finding of this research measured center of pressure trajectory in steppage gait over time, which is useful for designing better shoe sole and also orthopaedic device and better understanding of stability in patients with drop foot.

Modeling of the aorta artery aneurysms and renal artery stenosis using cardiovascular electronic system.

BACKGROUND: The aortic aneurysm is a dilatation of the aortic wall which occurs in the saccular and fusiform types. The aortic aneurysms can rupture, if left untreated. The renal stenosis occurs when the flow of blood from the arteries leading to the kidneys is constricted by atherosclerotic plaque. This narrowing may lead to the renal failure. Previous works have shown that, modelling is a useful tool for understanding of cardiovascular system functioning and pathophysiology of the system. The present study is concerned with the modelling of aortic aneurysms and renal artery stenosis using the cardiovascular electronic system. METHODS: The geometrical models of the aortic aneurysms and renal artery stenosis, with different rates, were constructed based on the original anatomical data. The pressure drop of each section due to the aneurysms or stenosis was computed by means of computational fluid dynamics method. The compliance of each section with the aneurysms or stenosis is also calculated using the mathematical method. An electrical system representing the cardiovascular circulation was used to study the effects of these pressure drops and the compliance variations on this system. RESULTS: The results showed the decreasing of pressure along the aorta and renal arteries lengths, due to the aneurysms and stenosis, at the peak systole. The mathematical method demonstrated that compliances of the aorta sections and renal increased with the expansion rate of the aneurysms and stenosis. The results of the modelling, such as electrical pressure graphs, exhibited the features of the pathologies such as hypertension and were compared with the relevant experimental data. CONCLUSION: We conclude from the study that the aortic aneurysms as well as renal artery stenosis may be the most important determinant of the arteries rupture and failure. Furthermore, these pathologies play important rules in increase of the cardiovascular pulse pressure which leads to the hypertension.

Simulation of the cardiovascular system using equivalent electronic system.

This paper describes simulation of the cardiovascular system using a complex electronic circuit. In this study we have taken a slightly different approach to the modeling of the system and tried to advance existing electrical models by increasing more segments and parameters. The model consists of 42 segments representing the arterial system. Anatomical and physiological data for circuit parameters have been extracted from medical articles and textbooks. The frequency of heart is 1 Hz and the system operates in steady state condition. Each artery is modeled by one capacitor, resistor and inductor. The left and right ventricles are modeled using AC power suppliers and diodes. The results of the simulation including pressure and volume graphs exhibit operation of the cardiovascular system under normal condition. The results of the simulation have been compared with the relevant experimental observation and are in good agreement with them.