Frequency Spectrum Growth Index

This systematic review aimed to evaluate the effects of various corrective exercises and supportive tools in individuals with genu valgum. To ensure a comprehensive review, a search for original research, review articles, and clinical trials in both Persian and English was conducted using databases such as WOS, SID, ISC, Magiran, Scopus, PubMed, and Google Scholar. The search covered publications during January 2008 to March 2023. A total of 76 relevant articles were selected based on strict inclusion and exclusion criteria, with 22 articles ultimately reviewed and analyzed regarding the effects of various corrective exercises and supportive tools on genu valgum. Findings from one study indicated that aerobic exercises had a significant impact on reducing body mass index (BMI) and the severity of genuvalgum. Other studies reported positive effects of resistance and corrective exercises on improving muscle electrical activity and knee stability. One study demonstrated that the use of orthotic insoles could significantly enhance knee joint support during stair descent. Six studies highlighted the positive effects of using orthoses, wedges, and braces in individuals with genu valgum. Conversely, one study pointed out the negative impact of these tools, citing the reduced limiting angle of the brace, increased applied forces, and, ultimately, greater injury risk. However, findings from three studies overwhelmingly supported the positive effects of using kinesiotape in individuals with genu valgum, providing optimism about the effectiveness of these interventions. In conclusion, our review underscores the promising potential of corrective exercises, particularly resistance exercises with TheraBand, and the combination of these with supportive tools such as insoles for arch support and kinesiotape. These interventions show significant promise in reducing the degree of knee valgus in individuals with genu valgum. This hopeful outlook can inspire healthcare professionals and individuals seeking evidence-based interventions for genu valgum, empowering them with the knowledge to make informed decisions about their care.


Keywords: Genu Valgum [MeSH], Exercise Therapy [MeSH], Kinesio Tape [MeSH], Orthotic Insoles [MeSH]

Background and Aims This study aimed to compare the frequency spectrum of ground reaction forces in blind and healthy participants with open and closed eyes during walking. Methods This study was quasi-experimental. The statistic samples comprised 15 blind men with a mean age of 25.22±6.33 years and 15 healthy men with a mean age of 27.22±5.31 years. They were selected by available sampling. A foot scan (RS Scan International, Belgium) device was used to measure the foot pressure values while walking. Variables of foot pressure were recorded at a sampling frequency of 300 Hz. For data analysis, we used the paired t test to compare the within-group means and the independent t test to compare the between-group means in SPSS software, version 24. Results The results showed that the frequency content with 99.5% power was greater in the blind group than in the healthy group with open eyes in the vertical direction, first metatarsal, and lateral and medial heel parts (P<0.05). Also, the frequency content with 99.5% power was greater in the healthy group with closed eyes than those healthy ones with open eyes (P<0.05). The frequency content with 99.5% power (P=0.004) and numbers of essential harmonics (P=0.003) in the vertical direction in the blind group were respectively 9.84% and 13.51% less than the healthy group with closed eyes. The number of essential harmonics (P=0.002) in the vertical direction in the healthy group with closed eyes was 20.61% greater than those healthy ones with open eyes. The frequency content with 99.5% power in the vertical direction in the blind group was less than that of the healthy group with closed eyes (P=0.023). Conclusion Considering the increase in frequency with 99.5% power and the number of essential harmonics in different areas of the soles of the foot in the blind group and healthy group with closed eye, it is recommended that physiotherapists, motion analysts, and rehabilitation specialists design a special rehabilitation protocol for blind people and those who lost their vision due to an accident.

As the shortage of the radio spectrum infers challenges in the Earth-Space Communication Link (ESCL) particularly in satellite communication, it is important to gauge the measure of attenuation to guarantee proficient usage of the spectrum. By the shortage in the frequency spectrum, the coming period will request more information to be exchanged at unquestionably more speed. Furthermore, this will interest for the higher frequencies. Keeping in mind the end goal to exploit present day space communications innovation, acknowledgment of a household correspondence satellite framework with impressive communication limit at Ku-band is attainable. Climate is exceptionally unverifiable and labile hydrometeor activities make issue in a satellite communication. The real issue connected with the communication links at these high frequency radio waves is the rain attenuation estimation. In this paper, a performance analysis and simulation of rain attenuation models is shown for frequency range of 12-40 GHz over ESCL at real urban communities of India by considering information of NSS-6 satellite.

Background and Aims Genu varus is one of the most common lower limb deformities that can affect a person's daily activities and sports performance. This study aims to investigate the effect of the 8-week use of knee braces on the electrical activity frequency of muscles in men with genu varus during walking. Methods This is a quasi-experimental study on 30 male college students with genu varus (aged 20-30 years) who were randomly divided into control and intervention groups. Corrective exercises were performed for 8 weeks using knee braces in the intervention group. The electrical activity of selected muscles was recorded by an electromyography system. For statistical analysis, ANCOVA was used. The significance level was set at 0.05. Results During the loading phase, the results showed a lower frequency of biceps femoris muscle in the intervention group compared to the control group (P=0.041). The frequency of muscles did not show any significant difference between groups in the mid-stance and push-off phases (P>0.05). Conclusion Given the decrease in the frequency of biceps femoris muscle activity in men who used knee braces, it can be concluded that the 8-week use of these brace can be effective in reducing shock absorption in the lower extremity.

Background and Objective: The ankle is one of the most vulnerable joints in the body in terms of weight bearing. The pronate foot is the most common complication of the lower limbs that causes a decrease in the height of the internal longitudinal arch when bearing body weight. This study was conducted to compare the effect of exercises in water and with thera-band on loading rate, impulse, and free torque in people with pronation immediately and after eight weeks.
Methods: This clinical trial was conducted on 45 male students with pronate foot at the University of Mohaghegh Ardabili. The subjects were randomly divided into three groups of 15 people including control, thera-band, and water training. The intervention groups performed the exercises for eight weeks and the immediate and long-term effects of the exercises were compared.
Results: The positive and negative peaks of free torque, vertical loading rate, and vertical impulse in the water training group after eight weeks decreased significantly compared to the pretest and immediately after exercise (P<0.05). Also, the internal-external direct impulse in the water training group increased significantly after eight weeks compared to the pretest and immediately after exercise (P<0.05). In addition, the positive peak of free torque and vertical impulse decreased significantly in the thera-band group after eight weeks compared to the pretest and immediately after exercise (P<0.05). Moreover, the loading rate decreased significantly immediately and after eight weeks in the thera-band group compared to the pretest (P<0.05).
Conclusion: Eight weeks of exercise in water and with thera-band can improve loading rate, free torque, and impulse in people with pronate foot during walking.

Background and Aim: Anterior cruciate ligament (ACL) injury is common in sports competition and training. Following ACL rupture, neuromuscular system performance is disrupted. Perturbation training can improve the function of patients with ACL reconstruction. The aim of the present study was to assess the effects of perturbation training on ground reaction force and functional status of these patients. Materials and Methods: Twenty patients with ACL reconstruction were randomly assigned into intervention (mean age: 24/2 ±3/4 years) and control (mean age: 27/1± 2/5 years) groups. The intervention group performed ten sessions perturbation training with rocker board, wobble board and Bosu. Peak vertical ground reaction force (GRF) and time to peak vertical GRF were recorded by KISTLER force plate during single leg landing from a 30cm height step. In addition, cross hop test also was evaluated as a functional test. Results: Before perturbation training, both GRF and time to peak vertical GRF in reconstructed knee had not significant difference between two groups (P>0/05). In addition, functional test score had not significant difference between the groups (P=0/62). Following perturbation training, peak vertical GRF in reconstructed knee was greater than that in control groups (P<0/003).Although time to peak vertical GRF in reconstructed knee increased, there was not statistically significant difference between two groups (P=0/50). Furthermore, functional test score was statistically greater in intervention group (P=0/03). Conclusion: This s tudy showed that perturbation training can improve functional status in patients with ACL reconstruction. In addition, force plate findings indicated that the patients tolerated more forces at longer time in single leg landing.

Background and Aims The increase in loading rate is associated with lower limb injuries such as tibial stress fracture. Quadriceps muscle activities absorb ground reaction force (GRF) shocks by eccentric activation. This study aims to evaluate the effect of aerobic training on the relationship between loading rate and quadriceps muscle activities in men with diabetic neuropathy (DN). Methods In this double-blinded, randomized, controlled clinical trial, participants were 40 men with DN who were selected by a convenience sampling method and randomly divided into two groups of training (n=20, age: 54.9±7.3, body mass index: 28.4±5.4) and control (n=20; age: 54.1±7.3, body mass index: 28.5±5.1). The GRF data was recorded using a force plate system during walking. The electrical activity of selected lower limb muscles was recorded using electromyography method. The training group performed aerobic training for 12 weeks (three sessions per week). Results The results showed an increase in the negative relationship between vertical loading rate and vastus lateralis activities after training (P=0.028). The activities of vastus medialis and rectus femoris muscles showed no significant relationship with loading rate after training (P>0.05). Conclusion Aerobic training can improve the relationship between vastus lateralis muscle activity and vertical loading rate in men with DN.

Dynamic Spectrum Access (DSA) technology in wireless Cognitive Radio Networks (CRNs) provides opportunistic access for unlicensed users, also known as Secondary Users (SUs), which can offer huge bandwidth to enable future wireless communication. Mainly, this technology aims to improve the endto-end throughput by allowing SUs to exploit the licensed channels only when their licensed users, also known as Primary Users (PUs), are not using them. Most existing communication protocols designed for CRNs are based on the assumption that the channel availability time is considered based on a memoryless distribution for PUs arrivals. Unfortunately, this assumption is impractical because the PU channels' activity and availability are memory-time correlated. Worse yet, designing communication protocols for CRNs under this assumption can result in overestimating the Probability of Success (PoS) for SU packet transmissions, resulting in severe degradation in network performance in realistic scenarios. This paper derives a closed-form formula under memory-time correlation for channel availability that quantifies the PoS for SUs' packet transmission in CRNs. This will empower the network designers to get practical expectations about network efficiency rather than the overestimated PoS. Therefore, this work is also useful for emerging wireless networks with multi-hop routing, such as 5G, 6G, vehicular networks, etc., which incorporate DSA techniques. Our numerical and simulation results demonstrate that the PoS is overestimated in most of the literature due to adopting memoryless-based distribution in modeling channels' availability; such overestimation can impact communication protocol decisions, resulting in severe network performance degradation.

Background and Aims Although volleyball is a contact sport, there are a high number of injuries in volleyball during training or competitions. Since many jumps are performed during training, it is not surprising that a high number of injuries are caused by jumping and landing. The present study aims to investigate the effect of taping on the feedforward activity of non-dominant leg muscles during singleleg jump-landing in professional volleyball players with chronic ankle instability. Methods In this study, participants were 13 volleyball players with chronic ankle instability who were selected by a purposive sampling method. Electromyographic activity of peroneus longus, anterior tibialis, gastrocnemius, vastus lateralis, gluteus medius, and rectus femoris muscles of the non-dominant leg during a single-leg jump-landing task following a spike shot before and after taping was evaluated. Root mean square was used to calculate muscle activity before and after taping. The data were analyzed using paired t-test. The significance level was set at 0.05. Results The findings showed the significant effect of taping only on maximum feedforward activity (P=0.02) and average feedforward activity (P=0.03) of the peroneus longus muscle. The effect was not statistically significant for other muscles (P>0.05). Conclusion It seems that taping is not useful for improving the feedforward activity of muscles in volleyball players with chronic ankle instability during single-leg jump-landing. Hence, other exercises or methods are recommended for these players during recovery or training.

Cognitive radio networks (CRNs) have been widely used in various applications for effective radio spectrum utilization in recent years. It is essential to fend off the growing demand for this finite natural resource for next-generation communications. In CRNs, detecting the activity of the primary user requires opportunistic spectrum sensing for efficient usage of the available radio spectrum, which is a limited and exquisite resource. Thus, CRNs are the key component in solving the spectrum scarcity issue in the presence of primary user bands through secondary users. Cognitive radio AdHoc networks (CRAHNs) are a unique kind of CRNs where infrastructures less cognitive radio (CR) nodes are furnished. In CRAHN, the CR-MAC protocol works slightly differently from the traditional wireless network MAC protocols. Particularly, the proposed method includes a high traffic scenario under contention-based IEEE 802.11 DCF MAC protocol. Accordingly, it can be observed that both, throughput and delay, increase as the CW size and packet length of the 802.11 (DCF) MAC protocol for CRAHN varies. Therefore, this paper proposed a fuzzy-based optimization framework for the 802.11 (DCF) MAC protocol in CRAHNs. Furthermore, it optimized throughput and delay by training a database of input parameters, contention window, and packet length for the Mamdani and Sugeno fuzzy inference system (FIS) models of the 802.11 (DCF) protocol simultaneously. The experimental result of the proposed framework for CRAHN with FIS shows that altering the contention window increases throughput by 25% and reduces the delay by 38% compared to the IEEE802.11 (DCF) protocol for CRAHNs without FIS. Moreover, it is also revealed that the throughput is increased by and 7% and the delay is reduced by 40% to 50% due to altering the packet length. INDEX TERMS Cognitive radio AdHoc networks (CRAHNs), MAC protocol, 802.11 (DCF), FIS-based optimization LIST OF ABBREVIATIONS CRNs Cognitive radio networks CRAHNs CR-AdHoc network SU Secondary user PU Primary user CR-WLAN Cognitive Radio wireless Local area network MAC Medium access control CSMA/CA K th Carrier sense multiple access/collision avoidance RTS Request to send CTS Clear to send DCF Distributed coordination function TDMA Time division multiple access CDMA Code division multiple access FDMA Frequency division multiple access FIS Fuzzy inference system DTMC Discrete-Time Markov Chain DIFS Distributed inter frame spacing SIFS K th Short Interframe Space

Abstract—In this paper, we investigate the performance of multi-channel cognitive radio networks (CRNs) by taking into consideration the problem of channel assignment and link scheduling. We assume that secondary nodes are equipped with multiple radios and can switch among multiple channels. How to allocate channels to links and how much power used on each channel to avoid mutual interference among secondary links are the key problem for such CRNs. We formulate the problem of channel assignment and link scheduling as a combinatorial optimization problem. Then, we propose a the optimal solution and show that it converges to maximum optimum in some iterations by using numerical results. I.

In this paper, we propose an innovative self-organizing medium access control mechanism for a distributed cognitive radio network (CRN) in which utilization is maximized by minimizing the collisions and missed opportunities. This is achieved by organizing the users of the CRN in a queue through a timer and user ID and providing channel access in an orderly fashion. To efficiently organize the users in a distributed, ad hoc network with less overhead, we reduce the sensing period through parallel sensing wherein the users are divided into different groups and each group is assigned a different portion of the primary spectrum band. This consequently augments the number of discovered spectrum holes which then are maximally utilized through the self-organizing access scheme. The combination of two schemes augments the effective utilization of primary holes to above 95%, even in impasse situations due to heavy primary network loading, thereby achieving higher network throughput than that...

Background and Aims Single-leg landing is a difficult task for the lower limbs. This movement is very common in basketball and is one of the main causes of lower limb injuries, especially anterior cruciate ligament injuries. Single-leg landing causes a ground reaction force and torque to the lower limb. By increasing the internal torque and controlling the reaction force at the level of its application, the muscular strength of the lower limb can control the ground reaction force of the surface applied to the limb. This study aims to investigate the effects of 8 weeks of strength training on the ground reaction force in single-leg landing
Methods In this study, 20 semi-professional male basketball players were divided into two equal groups of test and control. The samples of both control and test groups were asked to perform three single-leg landings from a 40-cm platform on the force plate. Then, the test group underwent 8 weeks of lower limb strength training, and after the end of the training, the members of the test and control groups were asked to repeat the landing movement. An average of three movements per person was considered. For data analysis, the paired t test was used for intra-group comparison, and the 1-way ANCOVA method was used to compare inter-group effects. Statistical analysis of the study was performed using SPSS software version 20, at a significance level of 0.05 for all tests.
Results The results showed that the training program had no significant effects on the ground reaction force in the X direction in both internal and external directions, as well as, in the Y direction in the anterior and posterior directions, both within the group and between the groups. But, the training program had a significant and incremental effect on both within the group (P=0.005) and between the groups (P=0.002) in the Z direction. 
Conclusion The strength training program lacks enough effect to reduce ground reaction force applied to semi-professional basketball players during a single-leg landing movement.

This paper presents a new condition indicator using wavelet analysis for the purpose of fault detection in an AH-64 gearbox. Historically, vibration-based condition indicators from employed component monitoring equipment are derived from both temporal and spectral domain analysis. However, these indicators failed to accurately capture high order correlations for the gearbox study addressed in this paper. An improved approach is necessary to overcome limitations of traditional vibrational monitoring techniques. The proposed condition indicator is derived from the Morlet continuous wavelet transform. The power spectra obtained from the wavelet transform coefficients at a certain scale or frequency are added together and then are normalised to one composite signal, denoted by a numeric index. Concepts of the wavelet index are discussed. This index is applied using real-world vibration data from a tail rotor gearbox with an output seal leak as part of condition-based maintenance practices. Results demonstrate potential

This paper presents a new condition indicator using wavelet analysis for the purpose of fault detection in an AH-64 gearbox. Historically, vibration-based condition indicators from employed component monitoring equipment are derived from both temporal and spectral domain analysis. However, these indicators failed to accurately capture high order correlations for the gearbox study addressed in this paper. An improved approach is necessary to overcome limitations of traditional vibrational monitoring techniques. The proposed condition indicator is derived from the Morlet continuous wavelet transform. The power spectra obtained from the wavelet transform coefficients at a certain scale or frequency are added together and then are normalised to one composite signal, denoted by a numeric index. Concepts of the wavelet index are discussed. This index is applied using real-world vibration data from a tail rotor gearbox with an output seal leak as part of condition-based maintenance practices. Results demonstrate potential

As the shortage of the radio spectrum infers challenges in the Earth-Space Communication Link (ESCL) particularly in satellite communication, it is important to gauge the measure of attenuation to guarantee proficient usage of the spectrum. By the shortage in the frequency spectrum, the coming period will request more information to be exchanged at unquestionably more speed. Furthermore, this will interest for the higher frequencies. Keeping in mind the end goal to exploit present day space communications innovation, acknowledgment of a household correspondence satellite framework with impressive communication limit at Ku-band is attainable. Climate is exceptionally unverifiable and labile hydrometeor activities make issue in a satellite communication. The real issue connected with the communication links at these high frequency radio waves is the rain attenuation estimation. In this paper, a performance analysis and simulation of rain attenuation models is shown for frequency range of 12-40 GHz over ESCL at real urban communities of India by considering information of NSS-6 satellite.

Background: Genu valgum is a postural malalignment in the knee joint. This malalignment is accompanied by altered mechanical forces in the tibiofemoral and patellofemoral joints. The purpose of this study was to investigate the effect of using a graded knee brace in two angles of 60 and 30 degrees on the frequency spectrum of ground reaction forces in individuals with genu valgum during landing. Methods: The present study was semi-experimental. Twenty non-athlete male students with genu valgus (age range: 20-30 years) were volunteered to participate in the study. The landing task was done during three conditions including without a knee brace, with a brace at two 30 and 60 degrees of flexion from a height of equal to 30 cm. Bertec force plate was used to record ground reaction forces. Fourier transform was used to calculate ground reaction force-frequency content during both landing conditions with and without a knee brace. Results: The results of this study showed a significant red...

Condition vibration data from eleven gearboxes run to failure on the mechanical diagnostic test-bed at Penn State University Applied Research Laboratory was processed calculating the fault growth parameter (FGP) from the residual error signal. FGP, its revised version FGP1 and some other variables calculated from the residual error signal were analysed using the proportional-hazards modelling technique. Several statistical and replacement decision models were built based upon the observed condition data and ensuing failure events.

Results of analysis carried out on data of Covid19, in Tabasco State, are presented, from March 2020 to February 2022. The procedure named 7 day´s moving average was applied to smooth the original graph and, in this way, analyze the data more easily. Fast Fourier transform (FFT) was applied to find the frequency that allows us to detect the period (in weeks) of generation of greater Covid19 infections. FFT allows us to determine that for a period of 14n weeks (n=1,3,5,7) there will be a new outbreak. The analysis of data reveals, during the first wave, the week with the highest number of infections was July 7-12 (2751 cases), that is in week 14 (n=1). FFT indicates that the second wave of infection would be in week 42 with n=3, the maximum was obtained at week 40 (2122 cases). The next prediction (variant Delta) was for week 70 (n=5), where there would be a high number of cases (thrid wave); real data indicates that it was reached in week 73 (7,023 cases). The four-wave (Omicron) is predicted for week 98, however, it was reached in week 94 (12,834 cases). It should be noted that due to the high transmissibility of Omicron, the number of infection grew fast during January 2022, so in this case, the difference between the prediction and the reality, present a difference of four week, however, for week 94 number of cases remains very high (1265 cases). FFT has turned out to be an adequate tool to make predictions of four waves that have occurred in Tabasco.

Background and Aims One of the most common and dangerous injuries in sports is an Anterior Cruciate Ligament (ACL) injury. Today, despite the ACL injury prevention programs, the prevalence of this injury remains high. Most of the instructions used in injury prevention programs are based on internal focus, while studies have shown that using external focus can improve performance in individuals. The purpose of this study was to investigate the effect of focus of attention on eight weeks of anterior cruciate ligament injury prevention training on landing skill kinetic variables in soccer players. Methods The current methodology included 35 players from 3 premier league teams in Tehran province. The teams were randomly divided into three groups of Prevent injury and Enhance Performance (PEP) exercises based on the External Focus (EF) (12 people), Internal Focus (IF) (12 people), and control group (11 people). In the pretest of ground reaction force, rate of loading, and time to stabili...

Micromorphological analysis is used to improve our understanding of wetland site taphonomy and stratigraphy. Twelve profile columns from the Neolithic lakeshore site of Zug‐Riedmatt are macroscopically described here, microscopic analyses are applied to sediment facies, defining 14 sedimentary units (U): The natural basal sediment (U1) is carbonate‐rich, U2 a transition phase to the anthropogenic units U3 to U12. Uppermost are the natural carbonate‐rich U13 and U14. The creation of a micromorphological database and the application of 27 defined indices allow a better understanding of the natural, anthropogenic and taphonomic processes taking place at the site. Natural sediment input originated from Lake Zug, the nearby river Lorze with its delta, and a local marshy waterbody. Organic rich accumulations and calcitic ash played a major role in pH changes, leading to carbonate and silica dissolution, alongside bone alteration. Signs of degradation processes under aerobic and anaerobic conditions within a single layer points to complex, multiphase processes under changing water levels, a milieu belonging to both land and water, an amphibious environment. Finally, good layer preservation seemingly correlates to low aquatic reworking in a stable depositional context linked to the marshy area.

Hamstrings (Hams) to Quadriceps (Quadr) strength ratio is known as a risk factor for Anterior Cruciate Ligament (ACL) injury and affects by knee and hip flexion angles. Gluteus Maximus (Gmax) muscle acts as a synergist for Hams in hip extension in a closed kinetic chain. The aim of this study was to investigate the effect of Gmax strengthening exercises on the kinetic and kinematic risk factors of ACL injury when single-leg landing from a jump. 25 volunteer women aged 18-30 years were assigned into control (n =13) and experimental (n =12) groups. Maximum isometric strength of Gmax, hip and knee joint angles and ground reaction force (GRF) was measured at landing, by dynamometer, 2D imaging and foot scan respectively,. After 8 weeks of 3 sessions of Gmax resistance training, Following the significant within-subject difference for GRF (F=5.245, P=0.032) by using Two-way mixed model ANOVA, Pre and post-test Differences were significant with 16.63% decrease (P= 0.038, t=2.354). Differences between pre and post-test peak force, time to peak, mean joint angles, impact and load rate were not significant (α = 0.05). According to a 4.55% and 3.47% increase in Gmax strength and time to peak force, and considering the fact that at the beginning of landing, the mechanical advantage of Hams is lower than that of Gmax, the risk of ACL injury could be reduced by reducing GRF following an increase in the Gmax strength.

Genu varus is one of the malalignment of the lower limbs, the failure to correct it leads to secondary abnormalities in adulthood. The purpose of this study was to investigate the effects of a corrective exercise program on ground reaction forces, loading rates, impulses and free moment during stance phase of walking. 17 children with genu varus were volunteered to participate in this study (Age:11.71±1.68 years, Height:1.40±0.09 meter, Weight:35.14±11.47 Kg, and BMI:17.49±3.61Kg/M2). Ground reaction forces were recorded with two Kisler force plates during pre and post-test. At the dominant limb, the amount of time to peak in the mediolateral ground reaction force component during heel contact decreased by of 61.90% (P=0.011). Also, the time to peak of the vertical ground reaction force component during mid-stance tend to increase significantly by 11.47% during the post-test compared to the pre-test (P=0.063). The values of peak ground reaction force components, loading rate, impulse and free moment did not show any significant differences between pre and post-test. The findings showed that the corrective exercise trainings used in the present study had the most effect on the time to peak components of the GRF, but there were no significant effects on the loading rate, impulses, and free moment components. The corrective exercises used in the present study have had the most effect on the time to peak of ground reaction forces and improve them. On the other hand, these exercises did not have any significant effect on the vertical loading rate, impact and free moment values.

Introduction and aim: Taping is a common method used by athletes to improve muscular function. The aim was to assess the immediate effect of femoral external rotational and abductoral taping on three-dimensional ground reaction force characteristics, their time to peak, impulse, displacement of center of pressure, vertical loading rate, and free moment during stance phase of running. Method: 24 healthy men (age: 24.6±2.5 years; mass: 74.8±6.2 kg; 177.1±7.9 cm) were included in the study. Ground reaction force data was recorded by a Kistler force platform (sampling rate: 1000 Hz). Paired sample t-test was used for statistical analysis. Results: Compared to without taping condition, taping significantly reduced the peak impact and peak active vertical ground reaction forces during stance phase of running (P≤0.05; low to moderate effect size). Taping application increased and decreased the vertical loading rate (19%, P=0.047, moderate effect size) and the peak free moment values (P≤0.001), respectively. The values of the anterior-posterior and vertical impulses during taping condition were greater than that of without taping condition (P≤0.001; low effect size). Conclusion: Femoral external rotational and abductoral taping could improve the values of free moment, but this is not the case in vertical loading rate during the stance phase of running.

Background: Genu valgum is a postural malalignment in the knee joint. This malalignment is accompanied by altered mechanical forces in the tibiofemoral and patellofemoral joints. The purpose of this study was to investigate the effect of using a graded knee brace in two angles of 60 and 30 degrees on the frequency spectrum of ground reaction forces in individuals with genu valgum during landing. Methods: The present study was semi-experimental. Twenty non-athlete male students with genu valgus (age range: 20-30 years) were volunteered to participate in the study. The landing task was done during three conditions including without a knee brace, with a brace at two 30 and 60 degrees of flexion from a height of equal to 30 cm. Bertec force plate was used to record ground reaction forces. Fourier transform was used to calculate ground reaction force-frequency content during both landing conditions with and without a knee brace. Results: The results of this study showed a significant red...

Objective Numerous abdominal exercises with Swiss ball are used to improve core stability with strengthening and rehabilitation goals. It is claimed that the stability exercises have a greater impact on core muscle activation, but the validity of this claim is still in doubt. Moreover, there is no comprehensive study on the comparison of the core muscles activity in different core stability exercises. Therefore, the purpose of this study was to compare the Electromyography (EMG) activity of core muscles while performing side plank on stable and unstable (Swiss ball) surfaces. Methods Fifteen male students of Allameh Tabataba’i University were selected for the study based on inclusion and exclusion criteria. The EMG activity of gluteus medius, rectus abdominis, external oblique, and internal oblique muscles in subjects was recorded while performing side plank exercise on a fixed surface and a Swiss ball (2 sets of 5 seconds with a 30-second rest interval). Results There was a signifi...

A new system aimed at performing partial discharge measurements and condition assessment on electrical apparatus is presented. It is able to separate the conventional phase resolved partial discharge pattern into a series of sub-patterns, each of them containing partial discharge data generated by a single kind of defect, which makes easier identification of the source generating partial discharges. Application of the system to partial discharge data recorded on an hydrogenerator is reported to support its effectiveness.

Looking into the human body is very essential not only for studying the anatomy and physiology, but also for diagnosing a disease or illness. Doctors always try to visualize an organ or body part in order to study its physiological and anatomical status for understanding and/or treating its illness. This necessity introduced the diagnostic tool called medical imaging. The era of medical imaging started in 1895, when Roentgen discovered the magical powerful invisible rays called X-rays. Gradually the medical imaging introduced X-Ray CT, Gamma Camera, PET, SPECT, MRI, USG. Recently medical imaging field is enriched with comparatively newer tomographic imaging modalities like Electrical Impedance Tomography (EIT), Diffuse Optical Tomography (DOT), Optical Coherence Tomography (OCT), and Photoacaustic Tomography (PAT). The EIT has been extensively researched in different fields of science and engineering due to its several advantages. This chapter will present a brief review on the avai...

Background and Aim: An immaculate review of the literature reveals some changes on the vertical ground reaction force (VGRF) in ACL deficient knee subjects. However, the details are not clear yet. The current study aimed to study these changes in the ACL-deficient and apparently healthy knees of the coper and non-coper ACL-deficient knee subjects in comparison with the normal knees. Materials and Methods: Sixteen unilateral ACL-torn subjects included 8 copers and 8 non-copers were recruited in this quasi-experimental study and were compared with 16 normal knee subjects (8 subjects matched to each coper and non-coper groups). All subjects walked barefoot and with their preferred speed in a 6-meter walkway and placed their wanted foot on the platform of a Zebris pedobarograph tool. The patients were asked to place their injured and healthy feet separately on the platform. The control group placed their foot matched to the ACL-deficient legs on the platform. The testes were repeated so much to have five acceptable trials. The outcome measures included the peak F1Z, F2Z, F3Z of the vertical ground reaction force values and the times to reach these peak values as well as total stance time of the tested feet. Results: The results showed only a significant lower F 1 Z value in the non-coper ACL-deficient knee subjects (p=0.008). No significant changes were shown in the F 2 Z, F 3 Z or the times reach to F 1 Z, F 2 Z and F 3 Z values (p>0.05). The stance time of the coper ACL-deficient knee subjects increased significantly in the non-coper ACL-deficeint knee subjects when compared to the coper and healthy knees (p=0.005). Conclusion: The reduced F1Z of the vertical ground reaction force at initial contact as well as increased total stance time seen only in non-coper ACL-deficient knee subjects reveals inadequate compensatory mechanism in these patients as a counter force stress at initial contact and weight bearing. However, the coper ACL-deficient knee subjects compensated these forces with good strategies and walked very similar to the control group.

Background and Aims: Forward head posture is one of the most prevalent disorders in the cervical area. The objective of the present study was to investigate ground reaction force components during running in an able-bodied control group and in children with forward head posture. Materials and Methods: A total of 28 male children including 16 healthy controls and 16 children with forward head posture participated in the current study. Two Kistler force platforms were used to record the ground reaction forces during barefoot running. Peak ground reaction force components, their time to peak, impulses in all axes, and peak positive and negative free moments were assessed. Independent sample t-test was used for between-group comparisons. The significance level was set at p<0.05. Results: The findings indicated that running speed in children with forward head was smaller than that in control group (P<0.001). Time to peak for vertical (by 11.2%; medium effect size; P=0.035) and lateral (by 76.3%; large effect size; P=0.009) ground reaction force components in forward head group were greater than those in healthy group. Peak ground reaction force components and peak positive and negative free moment amplitudes were not found to be statistically different between the two groups (P>0.05). Conclusion: Running speed in children with forward head posture was lower than that in healthy control group, while the peak ground reaction force components were similar to those in control group. This altered running speed and ground reaction forces are suggestive of a lower mechanical efficiency of running in children with forward head posture. Children with forward head posture need interventions such as sport exercises to reduce peak ground reaction force components and free moment values during running.

The incidence of lower extremity injuries in young soccer players is high, but the risk factors for injuries are unknown. Thus, the aim of this study was to investigate relationship between static lower extremity alignment and injuries in adolescent soccer players. Four teams (78 players) playing at Tehran Asia vision adolescence primer league (14-16 years old) participated in this study. Before entering the season Navicular drop, quadriceps angle, knee hyperextension, genu varum and body mass index was measured. Players were monitored for musculoskeletal injuries through a season (7-month period). overall injury rate was 8.7 injuries/1000 player-hours (95% CI=7.01-10.10). Logistic regression modeling indicated that Navicular drop in preferred foot (OR=4.5; p=0.001), Q angel in preferred leg (OR=2.77; p=0.048), and genu varum (OR=4.06; p=0.021) were all associated with injuries but no association was found in other parameters. Players had an approximately 4.5 times greater chance of suffering a lower extremity injury if they have Navicular drop greater than 1.5 centimeter and approximately 2.77 times greater chance of suffering injury if they have Q angel greater than 15.5 degrees. These findings show that multiple anatomic measures such as Navicular drop, genu varum and Q angle can predict soccer players’ injuries. Results of this study are valuable for coaches and players for injury prevention.

The aim of this study was to compare the effects of two pedaling methods on lower limb muscles fatigue index and muscular activity in road cyclists. For this purpose eight road cyclists participated in two separately session in laboratory. They were pedaling with pushing technique in first session and circling (pullingpushing) technique in the other session. Surface electromyography activity of the Rectus Femoris, Vastus Medialis, Vastus Lateralis, Biceps Femoris, Semitendinosous, Gastrocnemius Medialis, Gastrocnemius Lateralis and Tibialis Anterior muscles of the subjects were recorded. Each session was performed according to predetermined protocol until exhaustion. There was a significant difference between pushing and rest phases during two pedaling techniques with higher muscle activity in pushing technique. Subjects during circling technique exhausted later. According to the results of this study, the circling technique caused lower muscle activity consequently, increases gross efficiency. It is recommended that road cyclists utilize the circling technique.

Introduction: A potential limitation of current ACL injury prevention training may be a deficit in the transfer of conscious, optimal movement strategies rehearsed during training sessions to automatic movements required for athletic activities. Instructional strategies with an internal focus of attention have traditionally been utilized, but may not be optimal for the acquisition of the control of complex motor skills. Conversely, external-focus instructional strategies may enhance skill acquisition more efficiently and increase the transfer of improved motor skills to sports activities

Objective: The purpose of the current study was investigation of the effect of feedback training utilizing external focus of attention on kinetic, kinematic, and functional factors of active subjects.


Materials and Methods: Twenty-four males (aged 24.83±2.77 years, BMI 22.20±1.8 kg/m2, and weight 72.20±9.30 kg) were randomly assigned to feedback (n=12) and control (n=12) groups. The Feedback group completed training 3 times a week for 8 weeks; training lasted 45 min in each session. Peak knee flexion angle was measured using 3D motion analysis during landing, peak vertical and posterior ground reaction force was measured using force plate set, and functional movement was measured using triple hop test. For data analysis repeated measures analysis of variance, independent-sample, and paired t tests were used.


Findings:  Results revealed that feedback training caused significantly increased peak knee flexion angle (p=0.001, pre=44.88±4.89, post=51.26±4.80, effect size=1.266), increased functional movement of subjects (p=0.006, pre=5.11±.51, post=5.21±.49, effect size=0.911), and decreased peek posterior ground reaction force (p=0.011, pre=-303±55.39, post=-271±45.83, effect size=0.877). There was no significant effect in peak vertical ground reaction force (p=0.134, pre=2076±426.79, post=1884±328.18, effect size=0.612 ).


Conclusion: Given the reported significant effect of training on peak hip abduction moment and functional movement of participants, coaches and athletes recommended that to reduce the risk factors associated with anterior cruciate ligament injury and increase athletic functional performance, feedback training should be used during training sessions.

Background and Aims: Since fatigue in different regions of the lower extremities can effectively alter the movement pattern of this part of the body and cause joint-related kinematic changes that increase the risk of injury and mental fatigue, which may be a factor in reducing productivity and injury. Therefore, the study of kinematic changes during fatigue can have helpful results. This study aimed to investigate the effect of lower extremity fatigue on knee joint kinematics during landing in adult soccer players. Methods: Ten adult male soccer players (Mean±SD = age: 20.7±1.05 years; Height: 178.9±4.17 cm; Weight: 71.55±8.04 kg) participated in this study. Subjects performed a pre-test, which included jumping and landing on a 40-cm box, and recording cameras of the valgus motion analyzer, flexion, and knee rotation. The Kingtools section of the plugin software attached to the Cortex software was used for segmentation and kinematic information. The lower extremity fatigue protocol ...

Background and Aims Since fatigue in different regions of the lower extremities can effectively alter the movement pattern of this part of the body and cause joint-related kinematic changes that increase the risk of injury and mental fatigue, which may be a factor in reducing productivity and injury. Therefore, the study of kinematic changes during fatigue can have helpful results. This study aimed to investigate the effect of lower extremity fatigue on knee joint kinematics during landing in adult soccer players. Methods Ten adult male soccer players (Mean±SD = age: 20.7±1.05 years; Height: 178.9±4.17 cm; Weight: 71.55±8.04 kg) participated in this study. Subjects performed a pre-test, which included jumping and landing on a 40-cm box, and recording cameras of the valgus motion analyzer, flexion, and knee rotation. The Kingtools section of the plugin software attached to the Cortex software was used for segmentation and kinematic information. The lower extremity fatigue protocol consisted of 10 repetitions of single-leg squats up to 90 degrees of knee flexion, 20 vertical jumps with a single leg, and 1 repetition of step-going up and down a 31cm step. The Borg scale was used to measure fatigue. Before and after the fatigue protocol, a single-leg hop was used to determine the level of fatigue. After the fatigue protocol, a post-test was performed. Data were analyzed using the Shapiro-Wilk test for normality of the data, and paired t-test was used to compare mean in pre-test and post-test independent variables. Results The paired t-test results for comparison of kinematic data showed that contact flexion had a significant difference from pre-test to post-test and other kinematic variables had no significant changes from pre-test to post-test. Statistical significance was considered at P≤0.05. Conclusion According to the findings of this study, it can be concluded that lower extremity fatigue in the present study partly caused kinematic changes in predicting ACL injury. Kinematic changes have included a decrease in Contact flexion, which is one of the predictors of ACL injury during landing.

Background and Aims One of the most common and dangerous injuries in sports is an Anterior Cruciate Ligament (ACL) injury. Today, despite the ACL injury prevention programs, the prevalence of this injury remains high. Most of the instructions used in injury prevention programs are based on internal focus, while studies have shown that using external focus can improve performance in individuals. The purpose of this study was to investigate the effect of focus of attention on eight weeks of anterior cruciate ligament injury prevention training on landing skill kinetic variables in soccer players. Methods The current methodology included 35 players from 3 premier league teams in Tehran province. The teams were randomly divided into three groups of Prevent injury and Enhance Performance (PEP) exercises based on the External Focus (EF) (12 people), Internal Focus (IF) (12 people), and control group (11 people). In the pretest of ground reaction force, rate of loading, and time to stabilization during landing skill. The training groups performed pep injury prevention exercises for eight weeks and related instructions instead of warm-up exercises. Control group players were performing the regular activities. ANOVA with repeated measures and one-way ANOVA and Tukey post hoc tests were used to evaluate changes Results The test results showed significant changes in vertical, anterior-posterior ground reaction force and rate of loading in the external focus group (P≤0.05). But there was no critical difference in time to stabilization and internal-external ground reaction force. Conclusion According to the results, external focus instruction has positive effects on kinetic components. Therefore, it is recommended that exercises based on these instructions be used to reduce the risk of ACL injury and to repair this injury.

The purpose of study was to compare the electromyography of leg muscles and the peak vertical ground reaction forces during single leg drop landing of men with genu varum deformity and normal knee.26 physical education male students participated in this research, including 13 subjects with genu varum and 13 with normal knee. Electromyogram activities of some of the leg muscles along with ground reaction forces were measured. Genu varum deformity was measured and recorded by a caliper. Subjects performed single-leg landing from a 0.3m height on to a force platform. Landing motions were divided into two phases: 100 ms preceding ground contact and 100 ms after ground contact (absorption phase). Independent t- test was administered for the statistical analysis of data using SPSS software, version 16 (P≤0/05).The results of the study showed that no significant difference was found in the activities of the soleus, medialgastrocnemius and anterior tibialis muscles during pre-landing phase(...

A partial discharge (PD) classification methodology based counting PD pulses in the spectral domain is proposed and presented in this paper. The spectral counting data are processed using the proposed PD Spectral Pulse Counting Mapping technique (PD-SPCM), which leads to a Frequency-Resolved Partial Discharges (FRPD) map. The proposed map is then used for PD detection and classification. In this work, corona and slot FRPDs are presented in frequency bands up to 500 MHz, obtained from laboratory measurements performed using two hydro-generator stator bars. The electromagnetic signals from the PDs were captured using a patch antenna designed for this purpose and a spectral analyzer. The corona and slot PDs were chosen because one can be mistakenly classified as the other because they may present similar Phase Resolved PD (PRPD) maps and may occupy shared spectral bands. Furthermore, corona and slot PDs can occur concurrently. The obtained results show that the corona and slot PDs can ...

On-line partial discharge (PD) measurement in electrical insulation of the turbine generator (TG) is an essential approach to control the quality of insulation and to avoid any undesired shutdowns of TG. Although in the last few decades the number of research in PD on-line monitoring methods in the stator winding of TG has increased significantly, it is still not clear yet why PD only appears at certain phase angles of the AC cycle in the phase resolved partial discharge (PRPD) pattern. Moreover, there is not yet any clarification on how the winding configuration of stator may affect PD phase angle pattern. For this reason, this work examines detailed study of the impact of the winding diagram on PD occurrence in the stator winding of real turbine generator class TVF-60-2 (60 MW, 10.5 KV). In addition, a computer simulation of various sizes of ellipsoidal cavities from 0.1 to 2.5 mm between conductor bar and stator core were carried out by using Laplaces equation in Finite Element A...

Objectives: The aim of this study was to evaluate the effects of a corrective exercise protocol on frequency spectrum of landing ground reaction force in older adults with genu valgus during bilateral drop landing. Methods & Materials: The present study was a semi-experimental. 13 elderly men with genu valgus in experimental group and 13 elderly men with genu valgus in control group were volunteered to participate in this study (Clinical registration code: IRCT2016110230657N1). The ground reaction force data were measured by two Kistler Force Platforms. The training program include three sessions per week for 16 weeks. The participants signed written consent and the study design was approved by ethical committee. Those subjects with a history of injury were excluded from the study. The (2×2)ANOVA with repeated measure was used for statistical analysis. Results: The average age in experimental and control groups were equal to 63.92±2.21 and 64.01±2.62 years respectively. The results showed that the effect of time factor (by (2×2) ANOVA with repeated measure test) on the left vertical frequency content with power 99.5% (p=0.003) and number of essential harmonics in anterior-posterior direction (p=0.006) were significant. Also, the effect of group factor (by (2×2) ANOVA with repeated measure test) on the left vertical frequency with power 99.5% (p=0.006) and the number of essential harmonics (p=0.047) were significant. Furthermore, the effect of group*time interactions (by (2×2) ANOVA with repeated measure test) on the left vertical frequency with power 99.5% (p<0.001) and the number of essential harmonics (p=0.001) were significant. The results of paired sample t-test analyze showed that in the experimental group, the number of essential harmonics in vertical direction in the left leg during landing in the post-test was significantly greater than that in the pre-test (p=0.018). Conclusion: Totally, corrective training improved ground reaction force frequency content during landing in older adults with genu valgum.

Objectives: The aim of this study was to evaluate the effects of a corrective exercise protocol on frequency spectrum of landing ground reaction force in older adults with genu valgus during bilateral drop landing. Methods & Materials: The present study was a semi-experimental. 13 elderly men with genu valgus in experimental group and 13 elderly men with genu valgus in control group were volunteered to participate in this study (Clinical registration code: IRCT2016110230657N1). The ground reaction force data were measured by two Kistler Force Platforms. The training program include three sessions per week for 16 weeks. The participants signed written consent and the study design was approved by ethical committee. Those subjects with a history of injury were excluded from the study. The (2×2)ANOVA with repeated measure was used for statistical analysis. Results: The average age in experimental and control groups were equal to 63.92±2.21 and 64.01±2.62 years respectively. The results showed that the effect of time factor (by (2×2) ANOVA with repeated measure test) on the left vertical frequency content with power 99.5% (p=0.003) and number of essential harmonics in anterior-posterior direction (p=0.006) were significant. Also, the effect of group factor (by (2×2) ANOVA with repeated measure test) on the left vertical frequency with power 99.5% (p=0.006) and the number of essential harmonics (p=0.047) were significant. Furthermore, the effect of group*time interactions (by (2×2) ANOVA with repeated measure test) on the left vertical frequency with power 99.5% (p<0.001) and the number of essential harmonics (p=0.001) were significant. The results of paired sample t-test analyze showed that in the experimental group, the number of essential harmonics in vertical direction in the left leg during landing in the post-test was significantly greater than that in the pre-test (p=0.018). Conclusion: Totally, corrective training improved ground reaction force frequency content during landing in older adults with genu valgum.

Gearboxes are ubiquitous items of equipment in industry and pitting is one of the most frequent faults. To prevent the propagation of this fault to mechanical failure, it is necessary to monitor its initiation and evolution. Most of the current fault detection methods rely on vibration signals. The main idea of our work is to determine the detection potential and

The resistivity of biological tissue happens to be the basis of the field distribution inside the tissue. Hence the current injected in different patterns has a unique current distribution profile. The images of this field distribution are reconstructed using tools like FEMM and EIDORS. The work described here is the EIT based imaging of a closed phantom for detection of abnormality present. This system consists of 16 silver electrodes placed equidistant and detects non-conducting and conducting objects like clay and copper spindle in normal saline solution. The current is injected in two adjacent electrodes and the voltages are measured in neighbouring pattern at every consecutive pair of electrodes. The output data sets are used to reconstruct the voltage density distribution in closed phantom. The resulting images show that the resistivity profiles of the phantom for various events are successfully reconstructed. In this paper, the voltage density distribution is reconstructed into an image to detect the type, the location and the size of the abnormality present using FEMM tool.

Background and Aims Forward Head Posture (FHP) is one of the causes of cervical injury. The present study aims to evaluate the effect of a corrective exercise program on the electrical muscle activity in children with PHP during typing. Methods This quasi-experimental study was conducted on 30 children with FHP aged 11-13 years (Mean ±SD height=153.38±1.51 cm, Mean ±SD weight= 52.51±40.1 kg). To record the electrical activity of the muscles, a electromyography system was used. For statistical analysis, the two-way ANOVA was used. For all statistical analyses, the significance level was set at 0.05. Results In the exercise group, the post-test frequency spectrum in the levator scapulae and middle deltoid over the first and last 10 seconds of typing and in the sternocleidomastoid muscle in the final 10 seconds of typing were significantly different compared to the pre-test score. Conclusion The corrective exercise program can affect the frequency spectrum of the electrical muscle activity in children with FHP, which can prevent from early fatigue in the muscles.

Background and Aims More than 60 % of runners suffer from overuse injuries each year. Exercise and Running surfaces can prevent injuries and/or improve performance. The present study aims to investigate the effect of three types of running surfaces (Polyvinyl Chloride (PVC), artificial turf, and sand) on the Ground Reaction Force (GRF) components in the stance phase of running. Methods Impact force, loading rate, and free moment of 15 men were recorded while running barefoot on three PVC, artificial turf, and sand surfaces at a speed of 3±0.2 m/s (Average of 5 correct attempts). Comparison between different conditions was performed using repeated measures ANOVA and Bonferroni's Post-Hoc Test. Results The sand surface significantly reduced the impact force compared to the PVC and artificial turf. Both sand and artificial turf caused a significant reduction in the force loading rate compared to the PVC surface. The second peak of vertical GRF (propulsive force) increased at sand (P=0.001) and artificial turf (P=0.005) surfaces compared to the PVC surface. Moreover, the sand surface reduced adductor torque compared to the PVC (P<0.001) and artificial turf (P=0.003) surfaces, while the artificial turf reduced abductor torque compared to the PVC surface (P=0.011). Conclusion Sand is a safer surface for preventing running injuries due to eliminating impact force, reducing loading rate, and having high shock absorption. Training on a sand surface may improve performance on harder surfaces.

Background and Aims: Anterior Cruciate Ligament (ACL) injury is one of the most common non-contact lower extremity injuries among athletes. Ligament dominance is considered as one of the modifiable factors of ACL injury. This study aimed to evaluate the effect of plyometric training on electromyographic activity of hip abductor and adductor muscles in women with ligament dominance.
Methods: This is a randomized clinical trial conducted on 24 female athletes with ligament dominance, (Dynamic knee valgus angle >12 degrees), who were purposefully selected and randomly divided into two groups of training (n=12) and control (n=12). The training group performed plyometric training with verbal feedback for eight weeks, while the control group performed their regular training. The feedforward and feedback activity of hip abductor (gluteus maximus, gluteus medius, and tensor fascia latae) and adductor muscles (adductor longus) were assessed during a single-leg countermovement jump task 100 milliseconds before and after foot-ground contact. Paired t-test and multivariate covariance analysis were used to analyze the collected data. The significance level was set at 0.05.
Results: A significant increase in gluteal muscles activity and a decrease in adductor longus muscle activity was reported in the training group (p < 0.05), but not in the control group (P>0.05). In comparing the mean scores of the two study groups, a significant difference was observed in gluteal muscles’ feedforward activity (p < 0.05).
Conclusion: Eight weeks of plyometric training with verbal feedback can improve the electromagnetic activity of hip abductor and adductor muscles in women with ligament dominance and thus reduce the risk of ACL injury.

Already installed cables are aging and the cable network is growing rapidly. Improved condition monitoring methods are required for greater visibility of insulation defects in the cable networks. One of the critical challenges for continuous monitoring is the large amount of partial discharge (PD) data that poses constraints on the diagnostic capabilities. This paper presents the performance comparison of two data acquisition techniques based on phase resolved partial discharge (PRPD) and pulse acquisition (PA). The major contribution of this work is to provide an in-depth understanding of these techniques considering the perspective of randomness of the PD mechanism and improvements in the reliability of diagnostics. Experimental study is performed on the medium voltage (MV) cables in the laboratory environment. It has been observed that PRPD based acquisition not only requires a significantly larger amount of data but is also susceptible to losing the important information especia...

Objective Numerous abdominal exercises with Swiss ball are used to improve core stability with strengthening and rehabilitation goals. It is claimed that the stability exercises have a greater impact on core muscle activation, but the validity of this claim is still in doubt. Moreover, there is no comprehensive study on the comparison of the core muscles activity in different core stability exercises. Therefore, the purpose of this study was to compare the Electromyography (EMG) activity of core muscles while performing side plank on stable and unstable (Swiss ball) surfaces. Methods Fifteen male students of Allameh Tabataba'i University were selected for the study based on inclusion and exclusion criteria. The EMG activity of gluteus medius, rectus abdominis, external oblique, and internal oblique muscles in subjects was recorded while performing side plank exercise on a fixed surface and a Swiss ball (2 sets of 5 seconds with a 30-second rest interval). Results There was a significant difference in the EMG activity of gluteus medius, external oblique and rectus abdominis muscles between two conditions of with and without Swiss ball (P<0.05), but no significant difference was observed in the EMG activity of internal oblique muscle (P>0.05). Conclusion Side plank exercise on the unstable surfaces (Swiss balls) can cause changes in the EMG activity of gluteus medius, rectus abdominis and external oblique muscles compared to when the exercise is performed on stable surfaces, and highly involved the pelvic lumbar muscles effective in maintaining core stability. Therefore, the use of side plank exercise on unstable conditions in a progressive program with gradually increased intensity is recommended which can be effective in strengthening and applying effective muscle contractions useful for core stability.

Objective Numerous abdominal exercises with Swiss ball are used to improve core stability with strengthening
and rehabilitation goals. It is claimed that the stability exercises have a greater impact on core
muscle activation, but the validity of this claim is still in doubt. Moreover, there is no comprehensive
study on the comparison of the core muscles activity in different core stability exercises. Therefore, the
purpose of this study was to compare the Electromyography (EMG) activity of core muscles while performing
side plank on stable and unstable (Swiss ball) surfaces.
Methods Fifteen male students of Allameh Tabataba’i University were selected for the study based on
inclusion and exclusion criteria. The EMG activity of gluteus medius, rectus abdominis, external oblique,
and internal oblique muscles in subjects was recorded while performing side plank exercise on a fixed
surface and a Swiss ball (2 sets of 5 seconds with a 30-second rest interval).
Results There was a significant difference in the EMG activity of gluteus medius, external oblique and rectus
abdominis muscles between two conditions of with and without Swiss ball (P<0.05), but no significant
difference was observed in the EMG activity of internal oblique muscle (P>0.05).
Conclusion Side plank exercise on the unstable surfaces (Swiss balls) can cause changes in the EMG activity
of gluteus medius, rectus abdominis and external oblique muscles compared to when the exercise
is performed on stable surfaces, and highly involved the pelvic lumbar muscles effective in maintaining
core stability. Therefore, the use of side plank exercise on unstable conditions in a progressive program
with gradually increased intensity is recommended which can be effective in strengthening and applying
effective muscle contractions useful for core stability.

Objective Background The present research aimed to compare landing kinematics parameters at different minutes
of a simulated soccer game.
Methods In total, 15 soccer players from the youth team of Sanay Mes of Kerman with records (2 years) in the
Premier League of Iran voluntarily participated in this study. Their Mean±SD age and weight were 25.7±2.71
years and 77.30±7.78 kg, respectively. The players followed the Bangsbo's fatigue protocol, i.e. a simulated
soccer game. Then, every 15 minutes, the studied players performed two countermovement jumps, and we
compared their landing kinematics parameters accordingly. Performances were recorded with 3 cameras, 120
HTZ (Sony A7S). Information extracted from Kinova and repeated-measures analysis of variance was used for
data analysis.
Results The obtained results suggested significant differences between the investigated players' knee flexion
at landing at minute 0 and minute 60, and other durations (P<0.05). Moreover, there were significant differences
between dominant leg knee valgus at minutes 0, 60, and 105, and other durations. No differences were
detected between the non-dominant leg knee valgus at different minutes of the game.
Conclusion The obtained data revealed that minutes 0, 60, and 105 of a simulated soccer game are dangerous
times for Anterior Cruciate Ligament (ACL) injury in landing task. Moreover, the biomechanics of the dominant
leg in the landing tasks demonstrate more changes than the non-dominant leg. Furthermore, ACL injury in the
dominant leg is more frequent than the non-dominant one.