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The test-retest reliability of the H-Reflex and swaymeter in women aged 30–65 years

Background The H-reflex can objectively assess sensorimotor integration relevant to proprioception and postural control. Chemotherapy-induced peripheral neuropathy (CIPN) is a common and potentially dose-limiting side effect among breast cancer patients undergoing taxane-based treatments, leading to proprioception loss and balance issues, and an increased risk of falling. This study evaluated the between-day test-retest reliability of neurophysiological measures and postural sway, measured via swaymeter in a demographically similar population to those affected by breast cancer. Methods 25 women aged 30–65 years were assessed on two occasions, approximately two weeks apart. The study measured between-day test-retest reliability of the soleus H-reflex and M-wave and postural sway, measured by the swaymeter. Results The soleus maximum H-reflex amplitude (Hmax) and maximum M-wave amplitude (Mmax) exhibited good to excellent (ICC = 0.92, 95% CI: 0.82–0.96) and moderate to excellent (ICC = 0.81, 95% CI: 0.62–0.91) between-day reliability, respectively. The Hmax/Mmax showed poor to good between-day reliability (ICC = 0.63, 95% CI: 0.31–0.82), and H-reflex latency demonstrated moderate to excellent between-day reliability (ICC = 0.83, 95% CI: 0.65–0.92). The between-day test-retest reliability of anteroposterior (AP) displacement and total sway across the two testing sessions was poor to moderate (ICC = 0.37, 95% CI: −0.03–0.66 and ICC = 0.42, 95% CI: 0.04–0.70, respectively). Conclusions H-reflex and M-wave measures are reliable for between-day assessments. However, sway measures via swaymeter were less reliable, indicating a need for more robust tools to evaluate balance.

Optimization of rotor-side controller parameters in doubly fed induction generators based on an improved NSGA-II

Herein, an advanced control strategy to enhance the operational stability of wind turbine generators during grid-voltage surges is presented. In particular, a multiobjective optimization framework based on an improved nondominated sorting genetic algorithm II (NSGA-II) is proposed by establishing a dynamic model of the rotor-side converter and investigating the operational dynamics of proportional–integral–derivative controllers under voltage transients. Comparative simulations using the traditional NSGA-II, a multiobjective particle swarm optimization algorithm, and a multiobjective gray wolf optimization algorithm are conducted to validate the proposed algorithm. The improved NSGA-II exhibits superior robustness in suppressing equipment wear and minimizing harmonic distortions under transient conditions. These advancements highlight the potential of the proposed framework for enhancing grid resilience and operational efficiency in wind power systems.

Retraction: Design of a tomato classifier based on machine vision

Validity of pulse oximetry measures for heart rate and oxygen saturation during profound hypoxia in normobaric simulated extreme altitudes

Introduction Commercial pulse oximeters may not be well calibrated for oxygen saturations below 70%, conditions that may be met in high altitude aviation and mountaineering. We therefore examined the bias and variability of heart rate (HR) and blood oxygen saturation (SpO2) of four different pulse oximeters (PO) at arterial blood oxygen saturation (SaO2) between 55 and 100%. Methods Seventeen healthy participants (age 33 ± 11 (mean ± standard deviation (SD)) yr) were exposed to controlled desaturation at rest by stepwise reduction of the oxygen fraction in the breathing air between 20.9 and 8%. Parallel measurements of HR (n = 383) and blood oxygen saturation (n = 304) from four pulse oximeters (RAD-97, PM100N, M7500 and Nell1-SR) and from reference instruments (by hemoximetry and electrocardiography (ECG)) were taken during the exposure. The validity was assessed in intervals of 55–70%, 70–85% and 85–100% SaO2 using the Bland-Altman method (bias and 95% limits of agreement (LoA)) and the root mean square error for variability. The demarcation criteria for agreement between methods were ±6 percentage points O2Hb saturation and ±6 bpm HR. Results At the 85–100% SaO2 interval, all POs but the Nell1-SR were in agreement with the reference for O2 saturation. Only M7500 agreed with the reference for the 70–85% interval and none of the POs were in agreement with the reference for the 55–70% interval. The pulse oximeters and ECG were not in agreement for HR at neither the 55–70% nor the 85–100% interval but agreed at the 70–85% interval except the RAD-97. All pulse oximeters increased the bias or the variability for SpO2 significantly by reductions in oxygen saturation, while no systematic differences were found for HR. Conclusion The study shows that medically approved pulse oximeters are not in agreement with reference measurements of neither blood oxygen saturation nor HR at SaO2 levels below 70%, and their readings should therefore be interpreted cautiously during severe desaturation.

Enhancing pigment production by a chromogenic bacterium (Exiguobacterium aurantiacum) using tomato waste extract: A statistical approach

There is a high demand for microbial pigments as a promising alternative for synthetic pigments, primarily for safety and economic reasons. This study aimed at the optimization of yellowish-orange pigment production by Exiguobacterium aurantiacum using agro-waste extracts as a growth substrate. Air samples were collected using the depositional method. Pure cultures of pigment producing bacteria were isolated by subsequent culturing on fresh nutrient agar medium. The potent isolate was identified using MALDI-TOF technique. Screening of culture conditions was done via Plackett-Burman design that highlighted culture agitation rate, initial medium pH, and yeast extract concentration as the most significant variables ( p  < 0.0001) in influencing pigment production with further optimization step using response surface methodology. Among the tested agro-waste decoctions, tomato waste extract was selected for fermentation due to higher optical density of the isolate when cultivated in it compared to the other agro-waste extracts. Under optimized conditions, 0.96 g/L of pigment was extracted from 4.73 g/L of culture biomass, representing a 1.6-fold increase compared to un-optimized conditions. Spectroscopic and chromatographic analyses confirmed the presence of various functional groups, with carotenoids identified as the primary compounds responsible for the yellowish-orange pigmentation. These findings demonstrate the feasibility of enhancing bacterial pigment production using agro-waste substrates, highlighting its potential for large-scale industrial applications.

Mixing performance test and uniformity analysis of a two-stage injection jet on-line mixer

With the mixing of water and pesticides being a critical step, which is often performed using mixers. Traditional mixers, however, frequently exhibit issues such as uneven mixing and limited ratios. A dual-stage injection jet online mixer was designed to enhance the uniformity of pesticide and water mixing. This paper presents performance tests and uniformity analysis of this mixer, aiming to assess its effectiveness post-installation and to determine if it meets the required mixing performance and uniformity standards. Image analysis was utilized for qualitative assessment, revealing that the mixer’s two-dimensional curves in both axial and radial directions matched the pattern of pure pesticides. The root mean square error (RMSE) decreased with increasing mixing ratios, ranging from a minimum of 8.57% at a 300:1 ratio to a maximum of 9.94% at 2000:1. These variations were minimal, indicating good homogeneity across different ratios. Quantitative analysis using UV spectrophotometry showed that the actual mass concentration of the mixture deviated by less than 0.1% from the expected values at different sampling times, confirming superior temporal distribution uniformity. The variation in mixture mass concentration was insignificant across different locations, and the error variation at the same mixing ratio was less than 0.03%, indicating an excellent spatial distribution uniformity of the mixer. These findings demonstrate that the two-stage injection jet online mixer is effective over a wide range of mixing ratios, providing theoretical and technical support for accurate online variable spraying. This advancement is crucial for enhancing pesticide mixing efficiency and promoting sustainable agricultural development.

Recommendations for reporting regression-based norms and the development of free-access tools to implement them in practice

Norm-referenced tests compare individuals to a reference or source population. Norms usually depend on individual characteristics (norm-predictors) like age, gender, etc. Regression-based norming, a type of continuous norming, allows for exact evaluation of the test-taker’s score for any combination of the norm-predictors. Regression-based norms are often presented in tables and graphs in scientific papers, where only selected centiles for some combination of norm-predictors are summarized. Therefore exact score evaluation for any combination of norm-predictors is usually impossible because it requires a detailed presentation of all estimated model parameters which are usually undisclosed. Furthermore, the fitted models, like those from the R gamlss package, may include individual data that are usually protected by law and consent, which prevent data sharing. Thus, this paper provides recommendations for publishing regression-based norms that allow precise score evaluation for any combination of the norm-predictors while protecting participant privacy. We outline specific requirements for such publications: a) the exact presentation of the underlying fitted regression model that contains the estimates of all model parameters and other information required for exact evaluation; b) computer sharable fit of the model that does not contain any sensitive information and can be used by those with programming skills to evaluate scores; and c) a web-based application that can be used by those without programming skills to use the results of the fitted model. To facilitate publication and utilization of such regression-based norms, we have developed and provided an open-source R package of tools for authors and users alike. Following our recommendations, any user can access the underlying models while data privacy is maintained. This approach ensures broad accessibility and practical application of norms, allowing other researchers to accurately interpret their individual data against such norms.

Correction: Exposure to mass media chronic health campaign messages and the uptake of non-communicable disease screening in Ghana

Expression of Concern: Prevalence of type-2 diabetes and prediabetes in Malaysia: A systematic review and meta-analysis

Development of an omnidirectional rotating Compton camera for imaging 177Lu radioactive contamination

In this study, we developed an omnidirectional rotating Compton camera that was capable of imaging low-level radioactive contamination caused by 177Lu-oxodotreotide, a novel radiopharmaceutical that has recently been attracting attention in nuclear medicine. The detector employs a compact design that comprises only six scintillator crystals mounted on a motorized rotating stage. By optimizing the crystal type and size, and optimizing the interval between crystals, the detector is able to adapt to a wide range of environmental conditions, including observable gamma-ray energies, dose rates, and angular resolution. Monte Carlo simulations using Geant4 were conducted to optimize the configuration of the detector. Based on the results of the simulation, a prototype detector using six 3.5 cm cubic CaF2(Eu) crystals was developed for visualizing 177Lu-contaminated sites. The experimental results demonstrated that the detector could successfully visualize an unsealed 177Lu -oxodotreotide source with high sensitivity without being affected by gamma rays from 99TC, which is also present in nuclear medicine facilities. The developed rotating Compton camera technology is anticipated to serve as a reliable environmental monitoring tool in nuclear medicine facilities. Through its ability to rapidly detect radioactive contamination, this detector has the potential to reduce the radiation exposure risks for both medical professionals and the general public.

Automated facial feature evaluation system to prevent stress of head fixed mice

Head fixation of rodents is a widely utilized and important technique that enables laboratories to measure brain activity during behavior, but head fixation can increase stress which affects both behavior and underlying brain activity, as well as animal welfare. It is therefore critical to keep stress levels low, yet it is particularly challenging to assess stress in immobilized, head-fixed rodents. Conventional stress evaluation methods, such as blood corticosterone analysis, are labor-intensive and conducted post hoc, and In situ approaches require experienced personnel and constant vigilance during experiments. In this study, we present MouseCare, an automated software solution for immediate stress detection by real-time facial feature video analysis in head-fixed mice. MouseCare performs on par with or better than conventional stress measures, and is significantly less labor-intensive. This approach enables objective measures of stress that are needed to determine when an experiment can commence, but also when it should be stopped. We conclude that MouseCare offers a cost-effective and easily implementable strategy to manage stress levels in rodents that can increase data quality and improve animal welfare.

Anti-inflammatory, analgesic, antioxidant, and alpha-amylase inhibitory effects of the hydroethanolic leaf extract of Aleuritopteris bicolor (Roxb.) Fraser-Jenk.

Aleuritopteris bicolor (Roxb.) Fraser-Jenk. is used in traditional medicine in Nepal to treat a variety of ailments. This study aimed to investigate qualitative phytochemical screening, quantitative phytochemical analysis (total phenolic and flavonoid content estimation), in vitro antioxidant activity, alpha-amylase inhibitory activity of Aleuritopteris bicolor (Roxb.) Fraser-Jenk. leaves from Nepal. Furthermore, this study examined the analgesic (tail flick and hot plate test method) and anti-inflammatory (carrageenan-induced paw edema) activities of Aleuritopteris bicolor leaves in an acute pain and inflammation rat model. The Aleuritopteris bicolor extract exhibited flavonoid (405.95 ± 0.28 mg QE/g) and phenolic content (20.98 ± 0.20 mg GAE/g). Aleuritopteris bicolor showed free radical scavenging activity with IC50 value in difference antioxidant methods (IC50:9.87 µg/mL, DPPH scavenging assay; 249.59 µg/mL, Hydrogen peroxide; 72.98 µg/mL, Nitric oxide assay), and significant Ferric reducing power assay (0.51 ± 0.004). It increased analgesic activity by 38.89% (hot plate test) and 16.84% (tail-flick test) at 250 mg/kg, reduced inflammation by 36.44% at 180 min (500 mg/kg), and inhibited alpha-amylase activity (IC50:59.31 µg/mL). Aleuritopteris bicolor exhibits significant analgesic, anti-inflammatory, and hypoglycemic potential, making it a promising candidate for further pharmacological exploration. This study marks the first scientific study of the in vivo analgesic and anti-inflammatory effects from the leaf extract of Aleuritopteris bicolor till date.

Effects of childhood trauma on mental health outcomes, suicide risk factors and stress appraisals in adulthood

Background Childhood trauma has been identified as a significant risk factor for adverse mental health outcomes and increased suicide risk. However, the mechanisms by which stress-related variables, such as stress appraisal, influence this pathway remain unclear. The current study sought to: (1) investigate whether childhood trauma was associated with mental health outcomes (depression, anxiety), suicide risk factors (defeat, entrapment), and stress related outcomes (stress appraisal, perceived stress) in adulthood and (2) determine whether stress appraisal and perceived stress mediate the effects of childhood trauma on mental health outcomes and suicide risk factors. Method 273 participants were recruited to an online prospective study that consisted of two sessions with a one-week interval. In session 1, the childhood trauma questionnaire was completed. In session 2, participants completed measures assessing the level of depression, anxiety, defeat, entrapment, stress appraisal and perceived stress over the preceding week. Results Analyses found that childhood trauma was significantly associated with higher scores on depression, anxiety, defeat, entrapment, stress appraisal and perceived stress. Childhood trauma also had indirect effects on depression, anxiety, defeat, and entrapment through stress appraisal and perceived stress. Conclusion These findings underscore the enduring impact of childhood trauma on mental health outcomes and suicide risk in adulthood, mediated through its influence on stress appraisals and perceptions of stress encountered in daily life. These underlying mechanisms are critical for informing the development of future interventions.

Exploring the impact of a brief positive experience on dogs’ performance and stress resilience during a learning task

Learning and stress resilience can be influenced by recent experiences. Research has traditionally focused on the effects of negative situations and stressors on subsequent learning and stress resilience, while knowledge is limited regarding the effects of positive experiences. We aimed to examine the impact of a pre-session brief positive experience on dogs’ learning and stress resilience. Pet dogs were quasi-randomly assigned to the experimental (n = 20) or control (n = 20) group, counterbalanced for age, sex, and breed clade. Experimental dogs received a session intended to provide a positive experience, which included a 15 min walk on a long leash, human interaction, exploration, playing, and olfactory-based foraging. Control dogs were kept on leash in an office without being allowed to explore nor interact with their owner or the experimenters for 15 min. After 60 s of habituation to the testing room, all dogs were taught to nose-touch the experimenter’s hand. After the Learning phase, there was a 2 min Disruption phase, in which a remote-controlled car moved inside of a tub at a distance. Measures included the number of hand touches in each phase, the latency to return to the task, and general stress and affiliative behaviours. No differences were observed in the Learning phase. Surprisingly, experimental dogs exhibited higher stress levels than control dogs during the Disruption phase. These dogs also spent a significantly higher proportion of time in proximity to their owners, which could be interpreted as reassurance-seeking behaviour. Contrary to our predictions, exposure to a brief positive experience did not impact learning and, surprisingly, seemed to have made dogs more susceptible to stress during the Disruption phase. Several possible explanations are discussed, including the possibility of an unintentional induction of a negative emotional state by the termination of the positive experience, as well as differences in arousal, or habituation to the indoor environment.

Intervention through an intelligent technological platform for socio-emotional development and health promotion in adolescents with Type 1 Diabetes Mellitus (emoTICare): A study protocol for randomized controlled trial

Background During adolescence, individuals face various challenges that require adequate psychosocial and emotional adjustment. Additionally, the presence of a chronic illness during this stage, such as Type 1 Diabetes Mellitus (T1DM), introduces additional medical and psychological needs, which can increase vulnerability. In this context, serious games emerge as a promising tool to address educational and psychoemotional aspects while maintaining the motivation and playability typical of a video game. Currently, no technological tool simultaneously addresses both the educational and psycho-emotional needs of adolescents with T1DM. Aim This study aims to design and validate a psychological intervention program using a technological platform that incorporates artificial intelligence. Through the serious game emoTICare, the goal is to promote physical and emotional health in adolescents with T1DM by enhancing the development of socio-emotional skills. Method Test this tool, adolescents with T1DM will be recruited through diabetes associations across Spain. The participants, 372 adolescents aged between 12 and 16, will be randomly assigned to either a control or an experimental group. The experimental group will complete the emoTICare program. Over six weeks, participants will engage in psychoeducational activities using the tools provided by the serious game. Data Will be collected at three points: baseline (T1) and after six weeks (T2) (for the control group, T2 will be at the same time as the experimental group’s post-intervention), and aT3 (after six months of T2). The program’s effectiveness will be analyzed using various statistical packages. Results and conclusions The study hypothesizes that adolescents will maintain or improve their physical and emotional health indicators following the emoTICare program. Specifically, statistically significant improvements (p ≤ .05) are expected in the following variables: health-related quality of life, social skills and communication, emotional awareness, resilience, self-esteem, and coping and problem-solving abilities. Additionally, a statistically significant reduction (p ≤ .05) is anticipated in variables related to the perceived threat of the disease, as well as emotional and behavioral problems. The experimental group is expected to present improvements in all these areas when comparing pre- and posttreatment evaluations, and also in comparison to the control group on the waiting list.

Disability-adjusted life years, years lived with disability, and years of life lost of diseases among children and adolescents in national and subnational levels of Iran, 1990–2021: A systematic analysis for the Global Burden of Disease 2021

Introduction The global burden of disease (GBD) is a helpful measure that provides estimations regarding the effect of diseases and injuries on public health. This evidence is vital for making health policies and assessing the progress toward global health targets. Specifically, the burden of disease in children and adolescents can have a massive impact on a society’s health status. In this study, we aim to investigate the trends in years of life lost (YLL), years lost to disability (YLD), and disability-adjusted life years (DALYs) in children and adolescents under the age of 20 in Iran, based on GBD 2021 data. Methods The Global Burden of Disease (GBD) classifies all causes of death and disability into four levels. Level 1 includes three main categories: communicable, maternal, neonatal, and nutritional diseases (CMNNDs), non-communicable diseases (NCDs), and injuries. Level 2 expands these categories into 22 clusters of causes. This study provides a descriptive analysis of the trends in YLLs, YLDs, and DALYs at levels 1 and 2 of the GBD hierarchy, focusing on children and adolescents under the age of 20 in Iran and its 31 provinces from 1990 to 2021. Results All metrics show an overall decline. DALYs rate from all causes decreased by 79.8%, YLDs by 6.2%, and YLLs rate by 89.3%. This reduction was consistent across all metrics of CMNNDs, NCDs, and injuries, with the exception of YLD for NCDs, which showed a rise between 1990 and 2021; from 3733.4 (2742.7 to 5013.2) to 4036.1 (2941.5 to 5436.5) per 100,000 population. Mental disorders have significantly contributed to the upward trend of NCDs. NCDs, with a rate of 5666.2 per 100,000 population, exhibited the highest DALY rate in Iran in 2021. The trend of DALYs, YLLs, and YLDs of injuries and CMNNDs in Iran has been mostly downward. Differences between provinces have declined over thirty years. Following the COVID-19 pandemic, there have been changes in the trend of several diseases, especially the rise of mental disorders, respiratory infections and tuberculosis. Conclusion Despite the overall decline in DALYs, YLLs, and YLDs for most causes of death, there has been an increase in YLDs from NCDs, underscoring the importance of addressing this issue. Reviewing YLLs to YLDs ratios for various diseases and injuries, combined with economic analyses of the cost-effectiveness of various health interventions, yields comprehensive evidence for health policy making.

Microarray-based analysis reveals a novel role of the miRNA-613/SNAI2/CXCR4 axis in atrial fibrillation

Backgrounds Atrial fibrillation (AF) can lead to substantial morbidity and mortality in clinic. The previous studies demonstrated that miRNAs were closely associated with several cardiovascular diseases, however, the role of miRNAs in the pathogenesis of AF has not been fully elucidated. In order to investigate the important role of miRNA in the mechanisms of AF, we conducted the study through bioinformatics analysis. Methods We downloaded the miRNA expression profile (GSE68475) and mRNA expression profile (GSE31821) from the Gene Expression Omnibus (GEO) database to explore the differentially expressed miRNAs and mRNAs. The criteria for significant differentially expressed miRNA and mRNA using the R limma package were: adjusted P-value < 0.05, log2fold-change ≥ 1. The target mRNAs related to differentially expressed miRNAs of AF were predicted by using Functional enrichment analysis tool. We Screened overlapped mRNAs based on differentially expressed mRNAs and miRNA related mRNAs using Draw Venn Diagram. GO enrichment analysis and KEGG pathway analysis were conducted to explore the role of miRNAs and mRNAs in the pathogenesis of AF. Results A total of 70 differentially expressed miRNAs were screened including 33 up-regulated miRNAs and 34 downregulated miRNAs. All of 94 differentially expressed mRNAs were screened including 56 up-regulated mRNAs and 38 downregulated mRNAs. There were three co-expressed up-regulated differentially expressed genes, including CXCR4, SNAI2, and FHL1. We showed the results of GO functional enrichment analysis and KEGG pathway analysis ranked by enrichment score (-log P value) respectively. Conclusion Compared with patients of normal sinus rhythm, miRNA-613 was significantly down-regulated in patients with AF. We demonstrated that SNAI2 and CXCR4 may target genes of miRNA-613 for the first time. Our findings may provide new ideas for clarifying the molecular mechanism of atrial fibrillation.

Futility in healthcare among Mexican female patients with breast cancer in advanced stage: The patient perspective

Background Breast cancer is the leading cause of cancer-related deaths among women in Mexico, and the outcomes for patients are often poor. Futility in healthcare (FHC) occurs when treatment fails to achieve its intended goals, resulting in negative consequences. This study aimed to estimate the proportion of female patients in Mexico with advanced-stage breast cancer (ABC) who perceive FHC. Additionally, we inform the development and validation of a questionnaire (FHC-Q) to assess this phenomenon. Patients and methods This cross-sectional study was conducted from May 17, 2024, to December 30, 2024, in three phases. It involved three convenience samples (S) of adult women with ABC: S-1 (n = 30), S-2 (n = 201), and S-3 (n = 257). Phase 1 focused on constructing the FHC-Q, evaluating its content validity (expert agreement), and conducting a pilot test to assess its feasibility, all within S-1. Phase 2 involved assessing the questionnaire’s reliability (internal consistency and temporal stability), construct validity (correlations between FHC-Q and DASS21 scores, along with exploratory factor analysis), and criterion validity (correlations between FHC-Q and SF-36 scores), all in S-2. Phase 3 estimated the FHC phenomenon in S-3. The definition of FHC was established using the Delphi method. Results Participants represented typical female Mexican patients with ABC. The FHC-Q comprised 16 items distributed into five dimensions. The FHC-Q demonstrated feasibility and validity, with expert agreement of ≥80% and a five-factor structure explaining 57.8% of the variance. Correlations between the FHC-Q, DASS21 and SF-36 scores were significant and low to moderate. The FHC-Q reliability was confirmed with a Cronbach’s alpha of 0.766 and an ICC of 0.845 (95% CI: 0.735–0.909). FHC was perceived by 3.9% of the participants Conclusions FHC was perceived by a minority of Mexican women with ABC stages. The FHC-Q was valid, reliable and feasible to assess the phenomenon in the target population.

Financial inclusion and farmers’ income increase: Effects and realization mechanism

From the perspective of agricultural industrialization, based on China’s provincial data from 2006 to 2022, it studies the impact of financial inclusion on farmers’ income. We have found that financial inclusion can effectively promote the growth of farmers’ income, and this effect shows the heterogeneity of different income structures, income levels, and regional types. More importantly, agricultural industrialization is an important mechanism for financial inclusion to promote farmers’ income growth. However, the interactive effect of financial inclusion and agricultural industrialization has not promoted the growth of farmers’ income, indicating that there are certain structural problems in the current development of financial inclusion. We suggest that the development of financial inclusion should aim at the agricultural industrialization based on division of labor and cooperation. It can focus on supporting the development of local leading industries with regional comparative advantages, guide farmers to enter the agricultural industry chain, and improve farmers’ opportunities to share economic results.

The NW extension of the Nahavand Fault along the Main Recent Fault, west Iran

The MRF (Main Recent Fault) is an active fault zone in the western Iranian Plateau. The Nahavand Fault, an active 80-km segment of the MRF, lies between the Sahneh Fault to the northwest and the Qaleh-Hatam and Dorud faults to the southeast. The aim of this study is to examine the northwestern extension of the Nahavand Fault beneath Quaternary alluvial deposits. For this purpose, detailed field studies were conducted on a trench excavated perpendicular to the fault’s strike to determine the fault plane’s mechanism and characteristics. Additionally, data from the interpretation of two geoelectrical profiles were used to locate the surface trace of the fault beneath the alluvial deposits. The results indicate that, at the southeastern termination of the Nahavand Fault, the transpression stress regime has been overprinted by a transtensional regime. At its northwestern termination, the Nahavand Fault connects with the Sahneh Fault via a fault-bend pattern. The characteristics of the Nahavand Fault beneath the alluvial deposits of the Nahavand plain are N70°W/75°NE, with a rake of 15°. The Nahavand Fault extends northwestward with an updated length of approximately 80 km.