Gully erosion susceptibility mapping using multivariate adaptive regression splines-replications and sample size scenarios

Soil erosion is a serious problem affecting numerous countries, especially, gully erosion. In the current research, GIS techniques and MARS (Multivariate Adaptive Regression Splines) algorithm were considered to evaluate gully erosion susceptibility mapping among others. The study was conducted in a specific section of the Gorganroud Watershed in Golestan Province (Northern Iran), covering 2142.64 km2 which is intensely influenced by gully erosion. First, Google Earth images, field surveys, and national reports were used to provide a gully-hedcut evaluation map consisting of 307 gully-hedcut points. Eighteen gully erosion conditioning factors including significant geoenvironmental and morphometric variables were selected as predictors. To model sensitivity of gully erosion, Multivariate Adaptive Regression Splines (MARS) was used while the Area Under the Receiver Operating Characteristic (ROC) Curve (AUC), drawing ROC curves, efficiency percent, Yuden index, and kappa were used to evaluate model efficiency. We used two different scenarios of the combination of the number of replications, and sample size, including 90%/10% and 80%/20% with 10 replications, and 70%/30% with 5, 10, and 15 replications for preparing gully erosion susceptibility mapping (GESM). Each one involves a various subset of both positive (presence), and negative (absence) cases. Absences were extracted as randomly distributed individual cells. Therefore, the predictive competency of the gully erosion susceptibility model and the robustness of the procedure were evaluated through these datasets. Results did not show considerable variation in the accuracy of the model, with altering the percentage of calibration to validation samples and number of model replications. Given the accuracy, the MARS algorithm performed excellently in predictive performance. The combination of 80%/20% using all statistical measures including SST (0.88), SPF (0.83), E (0.79), Kappa (0.58), Robustness (0.01), and AUC (0.84) had the highest performance compared to the other combinations. Consequently, it was found that the performance of MARS for modelling gully erosion susceptibility is quite consistent while changes in the testing and validation specimens are executed. The intense acceptable prediction capability of the MARS model verifies the reliability of the method employed for use of this model elsewhere and gully erosion studies since they are qualified to quickly generating precise and exact GESMs (gully erosion sensitivity maps) to make decisions and management edaphic and hydrologic features

Evaluation of multi-hazard map produced using MaxEnt machine learning technique

Natural hazards are diverse and uneven in time and space, therefore, understanding its complexity is key to save human lives and conserve natural ecosystems. Reducing the outputs obtained after each modelling analysis is key to present the results for stakeholders, land managers and policymakers. So, the main goal of this survey was to present a method to synthesize three natural hazards in one multi-hazard map and its evaluation for hazard management and land use planning. To test this methodology, we took as study area the Gorganrood Watershed, located in the Golestan Province (Iran). First, an inventory map of three different types of hazards including flood, landslides, and gullies was prepared using field surveys and different official reports. To generate the susceptibility maps, a total of 17 geo-environmental factors were selected as predictors using the MaxEnt (Maximum Entropy) machine learning technique. The accuracy of the predictive models was evaluated by drawing receiver operating characteristic-ROC curves and calculating the area under the ROC curve-AUCROC. The MaxEnt model not only implemented superbly in the degree of fitting, but also obtained significant results in predictive performance. Variables importance of the three studied types of hazards showed that river density, distance from streams, and elevation were the most important factors for flood, respectively. Lithological units, elevation, and annual mean rainfall were relevant for detecting landslides. On the other hand, annual mean rainfall, elevation, and lithological units were used for gully erosion mapping in this study area. Finally, by combining the flood, landslides, and gully erosion susceptibility maps, an integrated multi-hazard map was created. The results demonstrated that 60% of the area is subjected to hazards, reaching a proportion of landslides up to 21.2% in the whole territory. We conclude that using this type of multi-hazard map may be a useful tool for local administrators to identify areas susceptible to hazards at large scales as we demonstrated in this research

Clinical and radiographic alterations in bilateral avascular necrosis of the femoral head following laser acupuncture: A case report

Introduction: Avascular necrosis (AVN) of the femoral head is an increasingly common cause of musculoskeletal disability with unknown etiology. Traumatic and non-traumatic factors can be effective in its occurrence. About 50 of cases are bilateral. The underlying treatment is prosthetic replacement surgical procedure. Case Presentation: We report a case of bilateral AVN of femoral heads who was a candidate for prosthetic replacement surgery but improved significantly, using laser acupuncture. The patient was a 55-year-old woman with a diagnosis of bilateral osteonecrosis of the femoral head for five years. As the patient declined the surgical option, laser acupuncture was started for pain control. Regarding the signs of bilateral femoral head recovery (according to the MRI scan criteria), a total of 3 courses of laser acupuncture (each course was 20 sessions) with 2 months intervals was performed. Ten acupuncture points: Li4, Li11, St36, SP6, LIV3, GB4, GB5, GB6, GB13, GB14, GB20, GB30, GB31, GB34, were irradiated bilaterally using red 650 nm laser, 100 mW, 1505 Hz frequency, duty cycle 50 3 J/point and near infrared 810 nm laser, 100 mW, 1705 Hz frequency, duty cycle 50 3 J/point, for 2 minutes. The patient received 3 laser therapy courses. During the first-course, laser therapy was done every other day to reduce pain. For the second and third courses, according to pain decrease, therapy was done every week. Results: The results of the MRI scans and x-ray studies show progressive regeneration of the right femoral head from VI to B II and of the left from V to C II (based on the standard table of Pennsylvania). Conclusion: It seems that this procedure may be mentioned in future research projects, especially in cases with high risks of surgery. © 2018, Laser Application in Medical Sciences Research Center

Clinical and radiographic alterations in bilateral avascular necrosis of the femoral head following laser acupuncture: A case report

Introduction: Avascular necrosis (AVN) of the femoral head is an increasingly common cause of musculoskeletal disability with unknown etiology. Traumatic and non-traumatic factors can be effective in its occurrence. About 50 of cases are bilateral. The underlying treatment is prosthetic replacement surgical procedure. Case Presentation: We report a case of bilateral AVN of femoral heads who was a candidate for prosthetic replacement surgery but improved significantly, using laser acupuncture. The patient was a 55-year-old woman with a diagnosis of bilateral osteonecrosis of the femoral head for five years. As the patient declined the surgical option, laser acupuncture was started for pain control. Regarding the signs of bilateral femoral head recovery (according to the MRI scan criteria), a total of 3 courses of laser acupuncture (each course was 20 sessions) with 2 months intervals was performed. Ten acupuncture points: Li4, Li11, St36, SP6, LIV3, GB4, GB5, GB6, GB13, GB14, GB20, GB30, GB31, GB34, were irradiated bilaterally using red 650 nm laser, 100 mW, 1505 Hz frequency, duty cycle 50 3 J/point and near infrared 810 nm laser, 100 mW, 1705 Hz frequency, duty cycle 50 3 J/point, for 2 minutes. The patient received 3 laser therapy courses. During the first-course, laser therapy was done every other day to reduce pain. For the second and third courses, according to pain decrease, therapy was done every week. Results: The results of the MRI scans and x-ray studies show progressive regeneration of the right femoral head from VI to B II and of the left from V to C II (based on the standard table of Pennsylvania). Conclusion: It seems that this procedure may be mentioned in future research projects, especially in cases with high risks of surgery. © 2018, Laser Application in Medical Sciences Research Center

Abdominal surgical site infections: incidence and risk factors at an Iranian teaching hospital

BACKGROUND: Abdominal surgical site infections are among the most common complications of inpatient admissions and have serious consequences for outcomes and costs. Different risk factors may be involved, including age, sex, nutrition and immunity, prophylactic antibiotics, operation type and duration, type of shaving, and secondary infections. This study aimed to determine the risk factors affecting abdominal surgical site infections and their incidence at Imam Khomeini, a major referral teaching hospital in Iran. METHODS: Patients (n = 802) who had undergone abdominal surgery were studied and the relationships among variables were analyzed by Student's t and Chi-square tests. The subjects were followed for 30 days and by a 20-item questionnaire. Data were collected through pre- and post-operative examinations and telephone follow-ups. RESULTS: Of the 802 patients, 139 suffered from SSI (17.4%). In 40.8% of the cases, the wound was dirty infected. The average age for the patients was 46.7 years. The operations were elective in 75.7% of the cases and 24.7% were urgent. The average duration of the operation was 2.24 hours, the average duration of pre-operative hospital stay 4.31 days and the average length of (pre- and post-operation) hospital stay 11.2 days. Three quarters of the cases were shaved 12 hours before the operation. The increased operation time, increased bed stay, electivity of the operation, septicity of the wound, type of incision, the administration of prophylactic antibiotic, type of operation, background disease, and the increased time lapse between shaving and operation all significantly associated with SSI with a p-value less than 0.001. CONCLUSION: In view of the high rate of SSI reported here (17.4% compared with the 14% quoted in literature), this study suggests that by reducing the average operation time to less than 2 hours, the average preoperative stay to 4 days and the overall stay to less than 11 days, and approximating the timing of shaving to the operation and substituting cefazolin for cefaluthin when prophylactic antibiotic is to be administered, the SSI may be reduced to a more acceptable level

Beliefs, attitude, and knowledge of the Iranian physiatrists towards neuromusculoskeletal ultrasound and common barriers in its application

Background: Regarding the increasing application of neuromusculoskeletal sonography among medical specialties, specifically physiatrists, this study aims to assess the knowledge and skill level of these specialists in neuromusculoskeletal sonography in Iran. Methods: This descriptive, cross-sectional study was performed in 2018. The utilized questionnaire developed based on previous studies in collaboration with 6 university lecturers of Shaheed Beheshti, Iran, and Tabriz medical universities and a physiatrist from Hacettepe University (Turkey); it included questions entailing demographic data, knowledge, and performance levels. Its validity and reliability were evaluated through face validation, pilot study, and the Cronbach α calculated via SPSS. Data extraction and analysis were also performed by SPSS-25. Results: Of 364 questionnaires distributed, 300 were properly filled and entered into the study, of which, 38 were filled by clinical residents, 10 university lecturers, and 52 other categories (e.g. private sector). The average number of musculoskeletal patient visits was 140.6 ± 119 and the mean number of musculoskeletal sonographies requested was 8.2 ± 5.2 per month (the three most common indications reported as the shoulder, carpal tunnel syndrome, and tendon injuries). 95 of the participants considered the importance of sonography for physiatrists to be �very high� or �high�; with the most valuable applications �as a guide for procedures (90), its diagnostic utility (68), and follow up/evaluating the response to treatment (45). 86 of physiatrists reported they had participated in musculoskeletal sonography courses, 60 during residency, and the rest through workshops. Also, the participants mentioned safety (83), the possibility of performing simultaneous diagnosis and intervention procedures (70), repeatability (58), and dynamic imagery (52) as the major advantages of musculoskeletal ultrasound. Conclusion: a large number of doctors consider musculoskeletal sonography to be essential for physiatrists, though insufficient education on the subject and the low number of ultrasound devices are some of the obstacles in enhancing the use of this technology in PM&R setting. Presenting certified specific training courses during residency, provision of necessary rotations, using the capacities of the PM&R scientific committee, and the private sector for running workshops and professional training courses are suggested for enhancing the knowledge and skills of neuromusculoskeletal sonography. © 2020, The Author(s)

Reliability of dynamic causal modelling of resting‐state magnetoencephalography

This study assesses the reliability of resting‐state dynamic causal modelling (DCM) of magnetoencephalography (MEG) under conductance‐based canonical microcircuit models, in terms of both posterior parameter estimates and model evidence. We use resting‐state MEG data from two sessions, acquired 2 weeks apart, from a cohort with high between‐subject variance arising from Alzheimer's disease. Our focus is not on the effect of disease, but on the reliability of the methods (as within‐subject between‐session agreement), which is crucial for future studies of disease progression and drug intervention. To assess the reliability of first‐level DCMs, we compare model evidence associated with the covariance among subject‐specific free energies (i.e., the ‘quality’ of the models) with versus without interclass correlations. We then used parametric empirical Bayes (PEB) to investigate the differences between the inferred DCM parameter probability distributions at the between subject level. Specifically, we examined the evidence for or against parameter differences (i) within‐subject, within‐session, and between‐epochs; (ii) within‐subject between‐session; and (iii) within‐site between‐subjects, accommodating the conditional dependency among parameter estimates. We show that for data acquired close in time, and under similar circumstances, more than 95% of inferred DCM parameters are unlikely to differ, speaking to mutual predictability over sessions. Using PEB, we show a reciprocal relationship between a conventional definition of ‘reliability’ and the conditional dependency among inferred model parameters. Our analyses confirm the reliability and reproducibility of the conductance‐based DCMs for resting‐state neurophysiological data. In this respect, the implicit generative modelling is suitable for interventional and longitudinal studies of neurological and psychiatric disorders

Derailment-based fault tree analysis on risk management of railway turnout systems

Railway turnouts are fundamental mechanical infrastructures, which allow a rolling stock to divert one direction to another. As those are of a large number of engineering subsystems, e.g. track, signalling, earthworks, these particular sub-systems are expected to induce high potential through various kind of failure mechanisms. This could be a cause of any catastrophic event. A derailment, one of undesirable events in railway operation, often results, albeit rare occurs, in damaging to rolling stock, railway infrastructure and disrupt service, and has the potential to cause casualties and even loss of lives. As a result, it is quite significant that a well-designed risk analysis is performed to create awareness of hazards and to identify what parts of the systems may be at risk. This study will focus on all types of environment based failures as a result of numerous contributing factors noted officially as accident reports. This risk analysis is designed to help industry to minimise the occurrence of accidents at railway turnouts. The methodology of the study relies on accurate assessment of derailment likelihood, and is based on statistical multiple factors-integrated accident rate analysis. The study is prepared in the way of establishing product risks and faults, and showing the impact of potential process by Boolean algebra

Predicting breast cancer response to neoadjuvant treatment using multi-feature MRI: results from the I-SPY 2 TRIAL.

Dynamic contrast-enhanced (DCE) MRI provides both morphological and functional information regarding breast tumor response to neoadjuvant chemotherapy (NAC). The purpose of this retrospective study is to test if prediction models combining multiple MRI features outperform models with single features. Four features were quantitatively calculated in each MRI exam: functional tumor volume, longest diameter, sphericity, and contralateral background parenchymal enhancement. Logistic regression analysis was used to study the relationship between MRI variables and pathologic complete response (pCR). Predictive performance was estimated using the area under the receiver operating characteristic curve (AUC). The full cohort was stratified by hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status (positive or negative). A total of 384 patients (median age: 49 y/o) were included. Results showed analysis with combined features achieved higher AUCs than analysis with any feature alone. AUCs estimated for the combined versus highest AUCs among single features were 0.81 (95% confidence interval [CI]: 0.76, 0.86) versus 0.79 (95% CI: 0.73, 0.85) in the full cohort, 0.83 (95% CI: 0.77, 0.92) versus 0.73 (95% CI: 0.61, 0.84) in HR-positive/HER2-negative, 0.88 (95% CI: 0.79, 0.97) versus 0.78 (95% CI: 0.63, 0.89) in HR-positive/HER2-positive, 0.83 (95% CI not available) versus 0.75 (95% CI: 0.46, 0.81) in HR-negative/HER2-positive, and 0.82 (95% CI: 0.74, 0.91) versus 0.75 (95% CI: 0.64, 0.83) in triple negatives. Multi-feature MRI analysis improved pCR prediction over analysis of any individual feature that we examined. Additionally, the improvements in prediction were more notable when analysis was conducted according to cancer subtype

Polymorphous adenocarcinoma of the salivary glands : reappraisal and update

Although relatively rare, polymorphous adenocarcinoma (PAC) is likely the second most common malignancy of the minor salivary glands (MiSG). The diagnosis is mainly based on an incisional biopsy. The optimal treatment comprises wide surgical excision, often with adjuvant radiotherapy. In general, PAC has a good prognosis. Previously, PAC was referred to as polymorphous low-grade adenocarcinoma (PLGA), but the new WHO classification of salivary gland tumours has also included under the PAC subheading, the so-called cribriform adenocarcinoma of minor salivary glands (CAMSG). This approach raised controversy, predominantly because of possible differences in clinical behaviour. For example, PLGA (PAC, classical variant) only rarely metastasizes, whereas CAMSG often shows metastases to the neck lymph nodes. Given the controversy, this review reappraises the definition, epidemiology, clinical presentation, diagnostic work-up, genetics, treatment modalities, and prognosis of PAC of the salivary glands with a particular focus on contrasting differences with CAMSG.Peer reviewe