Search

Background: One controversial question in Carpal Tunnel Syndrome (CTS) diagnosis is whether magnetic resonance imaging (MRI) and Ultrasound (US) imaging tools have any relationship with electrodiagnostic (EDX) study. The objective of this study is to determine the possible correlation between MRI and US measurements with EDX parameters. Methods: Both US and MRI of the median nerve were simultaneously performed in 12 confirmed CTS wrists, at two levels of forearm distal fold (proximal) and the hook of the hamate (distal), to measure various anatomic parameters of the nerve. EDX parameters of median motor distal latency (DL) and median sensory proximal latency (PL) were evaluated in milliseconds. Results: Nerve cross-sectional area (CSA), measured by MRI, correlated with sensory PL at distal level (p = 0.015). At proximal level MRI, nerve width and width to height ratio also correlated with motor DL (p = 0.033 and 0.021, respectively). Median nerve CSA proximal to distal ratio correlated with sensory PL (p = 0.028) at MRI. No correlation was found between US and EDX measurements. Conclusions: Median nerve MRI measurement of nerve CSA at hook of the hamate (distal) level or CSA proximal to distal ratio correlated with EDX parameter of sensory PL. On the other hand, nerve MRI width and width to height ratio at distal level correlated with motor DL in EDX. Level of Evidence: Level III (Diagnostic)

The stability of municipal solid waste (MSW) landfills is a significant environmental concern. The performance of landfills during earthquakes should be evaluated to ensure their stability. The geometry and material types of MSW landfills are the main factors affecting their seismic response. In this study, the individual and coupled impact of these factors is investigated using numerical analyses. Amplification factors (AFs = Accsurface/Accbase) are investigated for six common MSW landfill types, namely canyon type, hill type, side-hill types 1 and 2 and stepped-base types 1 and 2. The results show that landfill types have significantly different behaviours due to their geometry and waste material properties. For low stiffness contrasts, the stepped-base landfill type has the minimum and the hill type experiences the maximum AF, 1.74 and 3.53, respectively. However, for high stiffness contrasts, the canyon type has the minimum AF (0.46) due to the effect of damping and thickness of the waste. Therefore, the proper geometry of the MSW landfills should be designed for specific waste material properties according to the seismic response.

The stability of longwall coal mines has been a challenging concern for geotechnical and mining engineers. Rock-bolting is the commonly used support system preventing roof and wall convergence and floor heave. This study attempts to suggest an optimized new rock-bolting pattern to effectively prevent the convergence of transportation and ventilation tunnels in Tabas coal longwall mine at panels 2 and 3. Three-dimensional numerical analysis was performed on the support system using FLAC3d code. Investigating the rock bolts axial force applied to the ventilation tunnels roofs shows that, the safety factor of the new support system compared to the old one can be reduced by the ratio of 1.2 to 2, while the amount of the roof displacements are still within the allowable limit. Moreover, rock bolts installed in the transportation tunnels walls have yielded about 10 m from the working face, which became stable in the redesigned rock-bolting pattern. In order to decrease the floor heave, a support system with inclined bolts was proposed, in which the amount of floor heave in the transportation and ventilation tunnels decreased about 40% and 33%, respectively.

Radioactive materials are widely used in mining, manufacturing, medicine, and agricultural processes. The waste products from these materials are hazardous and should be appropriately dumped. As a result, a proper radiation shielding barrier is required to avoid the contamination of the surrounding environment. Clay soil is an efficient and eco-friendly radiation shielding material, which is commonly used to cap the hazardous and radioactive landfills. In this research, the effects of basalt fiber additive in four percentages, including 0.5, 1, 2, and 5 on the bentonite clay radiation shielding performance, were investigated using experimental and simulation methods. Also, the permeability of the mixtures is controlled to be in the acceptable range as a vital parameter for radioactive disposal barriers. Chemical and microstructure analyses were conducted on the utilized material, using energy-dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). Linear attenuation coefficient (μ), representing the material radiation shielding performance, was evaluated using the HPGe spectrometer detector, MCNP simulation code, and XCOM web program on the three commonly used gamma-ray energy levels of 137Cs (661.6 keV) and 60Co (1173.5 and 1332.5 keV). An acceptable agreement was observed between experimental and simulation results, revealing that adding basalt fiber improves the shielding performance due to a higher linear attenuation coefficient (μ), where 2% of basalt fiber leads to the highest values of 12.3 m−1, 10.14 m−1, and 8.5 m−1 obtained for 661.6 keV, 1173.2 keV, and 1332.5 keV energy levels, respectively. The results concluded that, due to radiation shielding performance, workability, and permeability limitations, the 2% basalt-bentonite mixture could be a new candidate covering low-level radioactive waste disposal.

Cutterhead torque and thrust are the two main designing parameters of the shield TBM, which have to be evaluated and optimized, based on the interaction between the TBM and excavated material. This study employs the discrete element method (DEM) to simulate the tunneling procedure of the line-7 of Tehran underground urban train tunnel utilizing the micro mechanical parameters calculated from back analysis on direct shear tests. The resultant torque and thrust are then compared against the actual parameters and then with those estimated from the numerical analyses. This result shows that DEM is able to estimate the TBM torque and thrust applying actual boundary conditions and material properties for the model. Furthermore, the impact of ground properties, overburden height, linear and radial velocity on cutterhead torque and thrust and its performance are evaluated and optimized.

BACKGROUND: It has been observed that patients with carpal tunnel syndrome (CTS) who also experience emotional distress, depression, or anxiety report more severe symptoms. As patients’ own perspectives about their health increasingly are guiding treatment decisions, it seems important to study the simultaneous association of psychological distress and neuropathology with hand disability in patients who have CTS, as this may help prioritize and sequence management steps. QUESTIONS/PURPOSES: What are the relationships among validated scores for (1) depression, (2) anxiety, (3) pain catastrophizing, and (4) nerve electrodiagnostic severity with measures of hand disability in patients with confirmed CTS? METHODS: Between 2017 and 2019, we evaluated 116 patients for CTS in a referral urban hospital in Mashhad, Iran. Of those, we considered 85% (99) as potentially eligible by considering the following Electromyography-Nerve Conduction Study (EMG-NCS) diagnostic criteria: sensory latency ≥ 3.5 Ms, median-ulnar latency difference ≥ 0.5 Ms, motor latency ≥ 4.2 Ms, and abnormal EMG findings in the opponens pollicis muscle (neurogenic motor unit action potentials, positive sharp waves, or fibrillation). A further 13% (15 of 116) were excluded because of nonidiopathic CTS and prior surgery, and another 12% (14 of 116) were lost because of incomplete datasets, leaving 60% (70 of 116) for final inclusion in this cross-sectional study. In all, 89% of patients were women with total mean age of 47 years. We measured depression and anxiety using the Hospital Anxiety and Depression Scale (HADS) questionnaire (scored from 0 to 21, with a minimum clinically important difference [MCID] of 1.7 points), and we evaluated patients’ state of mind regarding pain using the Pain Catastrophizing Scale (PCS) (scored from 0 to 52). Higher scores on these questionnaires represent more distress and pain catastrophizing. Hand disability was assessed with Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) questionnaire outcomes (scored from 0 [no disability] to 100 [most severe disability]; MCID of 15 points), Likert pain score (from 0 to 10), and grip/pinch dynamometry results. Correlational analyses were conducted once among HADS and PCS scores and again among EMG-NCS indices with pain and disability variables to answer our first, third, and fourth questions, respectively. Regression analysis was performed to assess the percentage of variance in QuickDASH and pain severity, which could be explained by psychological and electrodiagnostic factors. We did not include grip and pinch in our multivariable model (regression analysis) as dependent variables because they did not correlate with any of psychological or EMG-NCS variables (all p values > 0.1). Significance was set at p < 0.05. RESULTS: Correlational analysis showed that the scores of all three psychological questionnaires correlated with the QuickDASH score (r = 0.50, 0.42, and 0.53 for HADS-A, HADS-D, and PCS, respectively; p < 0.001 for all three), while EMG-NCS parameters had no correlation with QuickDASH and pain scores. We also found that 37% of the variance in QuickDASH score can be explained by HADS and PCS scores (r(2) = 0.37; p < 0.001). CONCLUSION: Evaluation and treatment of psychological distress before deciding on elective surgery for CTS is important because patient-reported disability—often used as a factor in surgical decision-making—is substantially correlated with emotional distress. Future prospective, controlled studies on this topic are recommended; ideally, these should evaluate psychological interventions specifically to ascertain whether they improve patients’ ratings of hand disability. LEVEL OF EVIDENCE: Level III, prognostic study.

Background: Stroke is the most common debilitating neurological disease in adults. Therefore, rehabilitation is a major consideration to reduce costs and relief disabilities. Biofeedback, a newly recommended method is claimed to be able to improve the consequences following stroke by enhancement the understanding of the psychological functions of the body. Objectives: The purpose of this study was to investigate the effect of biofeedback on the motor– muscular situation in rehabilitation of stroke patients Methods: The present study was a randomized clinical trial that was started in May 2016 and completed in September 2016. The sample of this study included all the patients with stroke attending the physiotherapy center of Imam Raza hospital in Mashhad, Iran. The participants were randomly divided into 2 groups (case and control group) after considering the inclusion and exclusion criteria. In the intervention group, biofeedback (2 times a week for 15 sessions, each session lasting 20 minutes) was performed.Before the intervention demographic information questionnaire was complete by all participants. Then a check list of main variables such as hands muscle strength, muscle stiffness (spasticity), balance and ability to walk was complete by a physician. In the 7th session of the exercise and in the end of intervention (14th session), again, the main variables of the check list were reassessed by the researcher. The statistical analysis was done by Statistical Package for the Social Sciences (SPSS) software version 16. Results: the mean score of balance evaluation in pre-intervention had not any significant differences (p=0.503), but in post intervention evaluation, this score in intervention group versus control group showed significant differences (p=0.014).the mean score of muscle strength,Results showed that by eliminating the effects of muscular strength before the intervention, this variable in both intervention and control groups after the intervention, had improvement and significant difference (p=0.005).Comparison the average spasticity, showed that spasticity evaluation score before and after intervention had no significant difference between the two groups (p=1.00) Conclusion: Considering the findings of this study, the biofeedback therapy is a promising treatment modality in improvement the motor– muscular condition following stroke.

Controlling the swelling of expansive clay soils is always challenging for geotechnicians. In this study, the effect of hollow polyester fiber as an additive on the free swelling percentage and pressure reduction of bentonite clay is investigated experimentally. The fibers are employed in two forms of spread and concentrated. Fiber dosages of 0.2, 0.5, 1, and 1.5 are employed for the spread form and fiber columns with diameters of 1.2, 2 and 3.2 cm, are considered for the concentrated form with fiber column densities of 30 and 60 kg/m3. The obtained results show a significant improvement in the swelling behaviour of bentonite for both the spread and concentrated forms, with better performance for the later form. In which, higher densities and larger diameters of the fiber columns generally decreases the swelling percentage and pressure. The best improvement was observed in the concentrated form sample, with 60 kg/cm3 density and 3.2 cm diameter, with 19 and 57 percent reduction in swelling percentage and pressure, respectively.

This paper develops a database for studying the circumstances under which dynamic loading of earthquake can cause slope failure in deep open pit mines with a long lifetime. The database includes 177 open pit mines hit by earthquake and 95 natural slopes and 37 tailing dams which have been failed by earthquakes. Both earthquake parameters and geomechanical characteristics involved in each case-study are investigated. From this information, the elements playing role in the earthquake-triggered failures in natural slopes and tailing dams are identified and used to indicate conditions that may result in earthquake-induced failures in open pit mines. The result shows that even though the valley shape geometry and absence of the top weathered layer make open pit mines less prone to earthquake-induced failures, excessive pore pressure in pit slopes still carries the risk of earthquake-triggered failures in open pit slopes. Only limited numbers of open pit mines have been so far exposed to earthquakes with the same parameters as those causing failure in natural slopes and tailing dams. That is, the response of open pit mines to higher magnitude, shallower, and closer earthquakes is still unknown. Studying the earthquakes that have caused failure in other slopes, it is concluded that open pit mines may still experience reportable failures if struck by earthquakes with local depth of less than 40 km, epicentral distance of less than 100 km, and magnitude of greater than 6.0. The necessity of accounting for seismic loading in slope stability analyses and active dewatering for open pit mines located in seismically active areas are also discussed.

There is global concern about the stability of rock slopes in open pit mines while the limit equilibrium technique used for modeling complex geometries and forces fails to provide a complete understanding of the behavior of rock slopes due to its inherent shortcomings. However, numerical approaches to modeling complex rock structures have improved the general understanding of these slope structures. In this study, geological and geotechnical data were obtained from both exploration drill holes and laboratory tests using face mapping and scanline surveys to reveal three major joint sets related to the regional tectonic history at the Cham-Shir dam power plant pit in Iran. The joints play an important role in the slope stability of the open pit, notably in terms of planar and wedge failures. Moreover, both the limit equilibrium technique and the discrete element method were employed to analyze the stability of the Cham-Shir dam power plant pit in an attempt to evaluate its behavior under both supported and unsupported conditions in the three modes of continuous rock mass, rock mass with two joint sets, and rock mass with three joint sets. Results show that the rock mass is stable in the continuous mode. The possible failure must, therefore, be due to the structure type and the joint sets at the site. To address the requirements and to resolve the problem, a simulation study was conducted. Based on the findings, stage by stage excavations are recommended for the study site.

Tractor as one of the most widely used agricultural machinery should be considered from different aspects. The frequent application of clutch and brake pedals and also the steering wheel within farms, along with the unfavorable working conditions, cause negative effects on the occupational health of the tractor drivers. Thus, in this research, the imposed forces on three engaged muscles including: Gastrocnemius, Trapezius and Quadrate’s lumborum of the tractor drivers during clutching have been studied. In this regard, algometer device was used to determine the applied forces on selective muscles of drivers during clutching of MF285 and MF399 tractors. The experiments were performed employing sample of 30 drivers and were conducted on two Iranian frequently used tractors including: MF285 and MF399 models. The results showed that the clutching forces for MF285 and MF399 tractors were 340 N and 290 N, respectively. The knee angle of the drivers of the two tractors was statistically different at the one percent level of significance. The reduction of pain threshold after 30 and 60 s clutching and also 60 s rest after clutching in MF285 tractor, for all three muscles, were more than those of MF399 tractor. The impact of clutching on the average decreases of pain threshold, for all drivers and all clutching periods, during and after clutching, in the Quadratus lumborum muscle was more than the other two muscles, in both tractors. In order to reduce the clutching force for MF285 tractor some modifications is suggested. In this regard the force transfer joint between the pedal and the clutch release linkage may be replaced with one made of cast iron.

Background: Hypnosis is a psychological method used for treatment of different types of disorders and illnesses. This technique is also used in surgical interventions. Many studies proved the efficacy of hypnosis in medical treatment. However, the mechanism of hypnosis is unclear for scientists. To find out if the peripheral nervous system has a role in hypnotic anesthesia, we aimed to investigate the effect of hypnotic anesthesia on nerve conduction velocity (NCV). Methods: In this study, healthy volunteers with high hypnotizability entered the study. First, The NCV test was performed in both hands of participants and then they all underwent hypnosis. Hypnotic anesthesia was induced in the right hand of all subjects followed by painful stimuli in their hand by vascular clasping. Then, the NCV test was repeated in both hands again. Data were analyzed by SPSS version16. Results: The group study consisted of 13 (65) women and 7 (35) men with their age ranging between 14 to 52 years. According to the results, the mean values of sensory latency, and NCV changed from 3.225 ms and 54.355 m/s before hypnotic anesthesia to 3.32 ms and 55.3 m/s after hypnotic anesthesia in right hand, respectively. Results showed that there was a significant difference between data before and after hypnotic induction (P < 0.001). The covariance test also indicated a significant difference between the data obtained from both hands (P < 0.001). Conclusions: In contrast to our hypothesis, the NCV test showed an increase after the hypnotic anesthesia. However, increase in NCV did not lead to experience pain after the painful stimuli. It seems that central nervous system should be involved in this process. © 2018, Anesthesiology and Pain Medicine.

Background: Neurodegenerative effects of illicit drugs have been proposed in many investigations. Amyotrophic lateral sclerosis is a fatal motor neuron disease characterized by degeneration of motor neurons, but the risk of amyotrophic lateral sclerosis among drug abusers is unknown. Methods: A nested case–control study was conducted in a teaching hospital to examine the association between drug abuse and amyotrophic lateral sclerosis. The study population included persons 18 to 40 years of age who were admitted in an electrodiagnostic medicine clinic for more than two year during the study period (January 2013 through April 2015) For each subject with ALS, 2 smoking-matched controls without ALS were randomly selected from the same population. Self-reported history of drug abuse was acceptable in both groups. Results: A total of 17 persons with ALS and 34 controls were identified, of whom 10 (58.8 percent) and 8 (23.5), respectively, had history of drug abuse. Persons with history of drug abuse had an increased risk of ALS (adjusted odds ratio, 2.6; 95 percent confidence interval, 1.2 to 5.7) as compared with controls. Conclusion: Drug abuse is an important risk factor for ALS, at least among young adults. The risk among drug abusers was at least or about double that among control group. The burden of mortality due to background ALS in drug abusers needs to be determined in future investigations.

We develop a database containing 95 historical natural slope and 37 tailing dam failures triggered by earthquake. The database analyses show that earthquake-triggered failures in natural slopes are mostly initiated in the narrow ridges. We also collect published data on 177 open pit mines struck by earthquakes of which 85 mines are located in the seismically active areas. The database indicates no reportable failures triggered by earthquakes in the affected mines. We employ a finite element code to investigate the geometrical and stiffness contrast effects distinguishing the behavior of natural slopes and tailing dams from open pit slopes experiencing earthquake dynamic loading. It is concluded that narrow ridge and the top soil layer in natural slopes and the hill-shaped geometry and unconsolidated top later of tailing dams amplifies the horizontal peak ground velocity by factor of 8 compared to open pit mine slopes. Our numerical modeling of the rock slopes suggests that the typical pit geometry and the competent material in open pit mines boost the slope stability through decreasing the topographical amplification effects.

Introduction: Immobilization in the elderly can reduce the size and strength of muscle mass and ultimately lead to sarcopenia, the severity and progression of which can be prevented by exercise. However, due to physical and mental conditions, the elderly may be unable to take full advantage of regular exercise. Therefore, fun exercise through motivation and effective participation of older adults is likely to have positive effects on decreasing the volume and power of muscle mass. The aim of this study was to determine the effect of fun physical activities on the progression of sarcopenia among elderly residents in nursing homes. Methods: This study was a two-group randomized controlled trial conducted in 2014. Sixty three older adults were recruited by the random sampling. The elderly in the fun physical exercise group did the exercise for 8 weeks, three times a week for 20 minutes at a time, and in the control group, the adults did the routine exercises. The Berg Balance Scale, a dynamometer, and the Six-Minute Walk Test were used to measure sarcopenia criteria (balance, muscle strength, distance traveled).The statistical analysis was done by SPSS version 13. Results: The results showed that the mean score of the sarcopenia criterion (balance, distance walked, muscles strength) was significantly increased in the fun physical exercise group than in the control group. Conclusion: The fun physical activity reduces sarcopenia progression through improving balance, increasing distances walked, and strengthening muscles.

Introduction: Incidence of nerve injury in traumatic hip dislocations is up to 10 %. Sciatic nerve is the most common injured nerve in this setting. In the medical literature, there are few documented cases of femoral nerve injury following hip dislocations. Case Report: We report a 44-year-old man with right femoral nerve palsy following delayed reduction of an anterior dislocation of hip. Conclusion: Two months after closed reduction, complete clinical recovery of right femoral nerve was achieved and the patient was able to resume his job.