Rapid quasi-periodic oscillations in the relativistic jet of BL Lacertae.

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare4 in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet5, plasma instabilities6,7 or orbital motion in an accretion disc7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. 9). BL Lac, the prototype of a subclass of blazars10, is powered by a 1.7 × 108 MSun (ref. 11) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. 12)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities6 near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

Blazar spectral variability as explained by a twisted inhomogeneous jet.

Blazars are active galactic nuclei, which are powerful sources of radiation whose central engine is located in the core of the host galaxy. Blazar emission is dominated by non-thermal radiation from a jet that moves relativistically towards us, and therefore undergoes Doppler beaming. This beaming causes flux enhancement and contraction of the variability timescales, so that most blazars appear as luminous sources characterized by noticeable and fast changes in brightness at all frequencies. The mechanism that produces this unpredictable variability is under debate, but proposed mechanisms include injection, acceleration and cooling of particles, with possible intervention of shock waves or turbulence. Changes in the viewing angle of the observed emitting knots or jet regions have also been suggested as an explanation of flaring events and can also explain specific properties of blazar emission, such as intra-day variability, quasi-periodicity and the delay of radio flux variations relative to optical changes. Such a geometric interpretation, however, is not universally accepted because alternative explanations based on changes in physical conditions-such as the size and speed of the emitting zone, the magnetic field, the number of emitting particles and their energy distribution-can explain snapshots of the spectral behaviour of blazars in many cases. Here we report the results of optical-to-radio-wavelength monitoring of the blazar CTA 102 and show that the observed long-term trends of the flux and spectral variability are best explained by an inhomogeneous, curved jet that undergoes changes in orientation over time. We propose that magnetohydrodynamic instabilities or rotation of the twisted jet cause different jet regions to change their orientation and hence their relative Doppler factors. In particular, the extreme optical outburst of 2016-2017 (brightness increase of six magnitudes) occurred when the corresponding emitting region had a small viewing angle. The agreement between observations and theoretical predictions can be seen as further validation of the relativistic beaming theory.

The incorporation of HIV self-testing as an exclusive option among men who have sex with men in Spain: results of an online cross-sectional study.

BACKGROUND: We assessed to what extent HIV self-testing would be incorporated by men who have sex with men (MSM) with previous testing history as their exclusive testing option and describe what actions they would take in the case of obtaining a reactive self-test. METHODS: We conducted an online survey among Spanish resident MSM recruited mainly in gay dating apps and analyze 6171 ever tested individuals. We used Poisson regression to estimate factors associated with the incorporation of self-testing as the exclusive testing option. Among those who would incorporate self-testing as their exclusive option, we described actions taken if obtaining a reactive self-test by number of tests in the past. RESULTS: Nearly half of the participants (48.3%) were > =35 years old, 84.6% were born in Spain, 57.9% had attained a university degree, 55.1% lived in a municipality of ≤500.000 and 86.4% self-identified as homosexual. For 37.2%, self-testing would become their exclusive testing option. The incorporation of self-testing as the exclusive option increased with age 25-34 (PR:1.1, 95%CI:1.0-1.3), 35-44 (PR:1.3, 95%CI:1.2-1.5), 45-49 (PR:1.5, 95%CI:1.3-1.7) and > 50 (PR:1.5, 95%CI:1.3-1.8) and in those who reported unprotected anal intercourse (PR:1.1, 95%CI:1.0-1.2) or having paid for sex (PR:1.2, 95%CI:1.0-1.3) in the last 12 months. It was also associated with having had < 10 HIV test in the past (2-9 tests (PR:1.3, 95%CI:1.1-1.4); 1 test (PR:1.5, 95%CI:1.3-1.7)), and having been tested ≥2 years (PR:1.4, 95%CI:1.3-1.5) or between 1 and 2 years ago (PR:1.1, 95%CI:1.0-1.2). Of participants who would use self-testing exclusively 76.6% would confirm their result in case of obtaining a reactive self-test and only 6.1% wouldn't know how to react. Only one individual expressed that he would do nothing at all. CONCLUSION: HIV self-testing could become the exclusive testing option for more than a third of our participants. It was chosen as the exclusive option especially by older, at risk and under-tested MSM. Self-testing strategies need to especially consider the linkage to care process. In this sense, only a small fraction would not know how to react and virtually nobody reported taking no action if obtaining a reactive result.

Novel micro/ultra/nanocentrifugation membrane process assessment for revalorization and reclamation of agricultural wastewater.

The concentration and recovery of the high-added value phenolic fraction from two-phase olive mill wastewater and the simultaneous effluent treatment by a novel micro/ultra/nanocentrifugation membrane process assessment is addressed, permitting to gather information for a correct and effective screening procedure for the adequate membrane election (MF-UF-loose NF) for the target. Phenolic compounds are the major factor of phytotoxicity of these effluents, but on the other hand they present high antioxidant properties that makes them very relevant for food, cosmetic, pharmaceutical and biotechnological industries. The selection of a membrane MWCO between 100 kDa and 0.45 µm permitted the complete transfer of the phenolic fraction to the permeate, whereas below 3 kDa they would be transferred to the concentrate stream instead, with ∼60% COD reduction and EC lowered to 551-662 µS cm-1 in the final treated stream ensured, sensibly improving the effluent quality. This would provide a purified effluent with good salinity standards according to the indications given by the FAO for irrigation reuse. This procedure could be quick and reliable for the assessment of the adequate membrane needed for a particular purification process, in contrast with long-term, time consuming common bench-scale procedures.

Infectious Complications Following Small Bowel Transplantation.

Microbiological spectrum and outcome of infectious complications following small bowel transplantation (SBT) have not been thoroughly characterized. We performed a retrospective analysis of all patients undergoing SBT from 2004 to 2013 in Spain. Sixty-nine patients underwent a total of 87 SBT procedures (65 pediatric, 22 adult). The median follow-up was 867 days. Overall, 81 transplant patients (93.1%) developed 263 episodes of infection (incidence rate: 2.81 episodes per 1000 transplant-days), with no significant differences between adult and pediatric populations. Most infections were bacterial (47.5%). Despite universal prophylaxis, 22 transplant patients (25.3%) developed cytomegalovirus disease, mainly in the form of enteritis. Specifically, 54 episodes of opportunistic infection (OI) occurred in 35 transplant patients. Infection was the major cause of mortality (17 of 24 deaths). Multivariate analysis identified retransplantation (hazard ratio [HR]: 2.21; 95% confidence interval [CI]: 1.02-4.80; p = 0.046) and posttransplant renal replacement therapy (RRT; HR: 4.19; 95% CI: 1.40-12.60; p = 0.011) as risk factors for OI. RRT was also a risk factor for invasive fungal disease (IFD; HR: 24.90; 95% CI: 5.35-115.91; p < 0.001). In conclusion, infection is the most frequent complication and the leading cause of death following SBT. Posttransplant RRT and retransplantation identify those recipients at high risk for developing OI and IFD.

Innate Lymphoid Cells Groups 1 and 3 in the Epithelial Compartment of Functional Human Intestinal Allografts.

We examined intraepithelial lymphocytes (IELs) in 213 ileal biopsies from 16 bowel grafts and compared them with 32 biopsies from native intestines. During the first year posttransplantation, grafts exhibited low levels of IELs (percentage of CD103(+) cells) principally due to reduced CD3(+) CD8(+) cells, while CD103(+) CD3(-) cell numbers became significantly higher. Changes in IEL subsets did not correlate with histology results, isolated intestine, or multivisceral transplants, but CD3(-) IELs were significantly higher in patients receiving corticosteroids. Compared with controls, more CD3(-) IELs of the grafts expressed CD56, NKp44, interleukin (IL)-23 receptor, retinoid-related orphan receptor gamma t (RORγt), and CCR6. No difference was observed in granzyme B, and CD3(-) CD127(+) cells were more abundant in native intestines. Ex vivo, and after in vitro activation, CD3(-) IELs in grafts produced significantly more interferon (IFN)-γ and IL-22, and a double IFNγ(+) IL-22(+) population was observed. Epithelial cell-depleted grafts IELs were cytotoxic, whereas this was not observed in controls. In conclusion, different from native intestines, a CD3(-) IEL subset predominates in grafts, showing features of natural killer cells and intraepithelial ILC1 (CD56(+) , NKp44(+) , CCR6(+) , CD127(-) , cytotoxicity, and IFNγ secretion), ILC3 (CD56(+) , NKp44(+) , IL-23R(+) , CCR6(+) , RORγt(+) , and IL-22 secretion), and intermediate ILC1-ILC3 phenotypes (IFNγ(+) IL-22(+) ). Viability of intestinal grafts may depend on the balance among proinflammatory and homeostatic roles of ILC subsets.

Porcine acellular dermal matrix for delayed abdominal wall closure after pediatric liver transplantation.

Children are one of the groups with the highest mortality rate on the waiting list for LT. Primary closure of the abdominal wall is often impossible in the pediatric population, due to a size mismatch between a large graft and a small recipient. We present a retrospective cohort study of six pediatric patients, who underwent delayed abdominal wall closure with a biological mesh after LT, and in whom early closure was impossible. A non-cross-linked porcine-derived acellular dermal matrix (Strattice(™) Reconstructive Tissue Matrix; LifeCell Corp, Bridgewater, NJ, USA) was used in all of the cases of the series. After a mean follow-up of 26 months (21-32 months), all patients were asymptomatic, with a functional abdominal wall after physical examination. Non-cross-linked porcine-derived acellular dermal matrix (Strattice(™) ) is a good alternative for delayed abdominal wall closure after pediatric LT. Randomized controlled trials are necessary to determine the best moment and the best technique for abdominal wall closure.

Machine learning approaches to evaluate infants' general movements in the writhing stage-a pilot study.

The goals of this study are to describe machine learning techniques employing computer-vision movement algorithms to automatically evaluate infants' general movements (GMs) in the writhing stage. This is a retrospective study of infants admitted 07/2019 to 11/2021 to a level IV neonatal intensive care unit (NICU). Infant GMs, classified by certified expert, were analyzed in two-steps (1) determination of anatomic key point location using a NICU-trained pose estimation model [accuracy determined using object key point similarity (OKS)]; (2) development of a preliminary movement model to distinguish normal versus cramped-synchronized (CS) GMs using cosine similarity and autocorrelation of major joints. GMs were analyzed using 85 videos from 74 infants; gestational age at birth 28.9 ± 4.1 weeks and postmenstrual age (PMA) at time of video 35.9 ± 4.6 weeks The NICU-trained pose estimation model was more accurate (0.91 ± 0.008 OKS) than a generic model (0.83 ± 0.032 OKS, p < 0.001). Autocorrelation values in the lower limbs were significantly different between normal (5 videos) and CS GMs (5 videos, p < 0.05). These data indicate that automated pose estimation of anatomical key points is feasible in NICU patients and that a NICU-trained model can distinguish between normal and CS GMs. These preliminary data indicate that machine learning techniques may represent a promising tool for earlier CP risk assessment in the writhing stage and prior to hospital discharge.

How Does Ball Possession Affect the Physical Demands in Spanish LaLiga? A Multilevel Approach.

Purpose: Using a multilevel approach, this study analyzed the relationship between ball possession and distance covered at different speed sections: total distance (TD), distance covered between 14.1-21 km·h-1 (MIRD), 21.1-24 km·h-1 (HIRD), and > 24.1 km·h-1 (VHIRD). Methods: The sample included 1,520 matches played by 80 Spanish professional soccer teams across four consecutive LaLiga seasons (from 2015/2016 to 2018/2019). Two observations were collected per match, one from each team, resulting in a total of 2,950 records (760 per season). Data were collected using Mediacoach®. Results: At match level (i.e., grand-mean centered), ball possession negatively predicted all distances covered. At team level (i.e., group-mean centered), ball possession negatively predicted total distance covered and distance covered between 14.1-21 km·h-1. Furthermore, cross-level interactions (Match X Team) in ball possession negatively predicted all distances covered at speeds above 14.1 km·h-1. Specifically, in high-possession teams, the negative relationship between match ball possession and distances traveled at all speed ranges above 14.1 km·h-1 was stronger than in teams with medium or low possession. Conversely, match ball possession was positively related todistance covered at low intensities, and negatively related at high intensities in low-possession teams. Conclusion: These findings show practitioners and researchers that the distances covered at different speed ranges depend on technical-tactical parameters such as ball possession.

Physical workloads of the upper-extremity among workers of the Colombian flower industry.

BACKGROUND: We report the prevalence of symptoms of common upper-limb disorders and describe comprehensively mechanical workloads in a sample of workers of the Colombian flower industry. METHODS: One hundred fifty eight workers from eight flower manufacturers were assessed. Assessments included Borg self-reported exertion and working practices, medical examinations, video-based observations and kinematic and surface muscular activity assessments of upper-limb. RESULTS: Point prevalence of signs and symptoms of CTS, epicondylitis, and De Quervain's disease was 32.9%, 15.2%, and 13.3%, respectively. All tasks are executed on average in wrist extension, ulnar deviation, and high elbow flexion. Average median muscle activity across tasks ranged between 3.6% and 27.3%. Forearm muscles were mainly active. CONCLUSIONS: The occurrence of signs and symptoms of upper-extremity musculoskeletal disorders was high among the sample. The classification and cutting task showed the highest mechanical demands. Interventions in this working population are required and should be directed to allow for muscular rest on regular basis.

A focus on pressure-driven membrane technology in olive mill wastewater reclamation: state of the art.

Direct disposal of the heavily polluted effluent from olive oil industry (olive mill wastewater, OMW) to the environment or to domestic wastewater treatment plants is actually prohibited in most countries, and conventional treatments are ineffective. Membranes are currently one of the most versatile technologies for environmental quality control. Notwithstanding, studies on OMW reclamation by membranes are still scarce, and fouling inhibition and prediction to improve large-scale membrane performance still remain unresolved. Consequently, adequately targeted pretreatment for the specific binomium membrane-feed, as well as optimized operating conditions for the proper membranes, is today's challenge to ensure threshold flux values. Several membrane materials, configurations and pore sizes have been elucidated, and also different pretreatments including sedimentation, centrifugation, biosorption, sieving, filtration and microfiltration, various types of flocculation as well as advance oxidation processes have been applied so far. Recovery of potential-value compounds, such as a variety of polyphenols highlighting oleuropein and hydroxytyrosol, has been attempted too. All this research should constitute the starting point to proceed with OMW purification beyond recycling for irrigation or depuration for sewer discharge, with the aim of complying with standards to reuse the effluent in the olive oil production process, together with cost-effective recovery of added-value compounds.

The relationship between running distance and coaches' perception of team performance in professional soccer player during multiple seasons.

This study analyzed how the physical movement profile of soccer matches evolved throughout a season by assessing the variability of different metrics depending on the season phase. In addition, the evolution of running distances was investigated in the relation to the team performance based on the coaches' perception. Games from four consecutives Spanish LaLiga seasons (n = 1520) were recorded using an optical tracking system (i.e., ChyronHego). Total distance (TD), distance covered between 14 and 21 km h-1 (MIRD), 21-24 km h-1 (HIRD), and > 24 km h-1 (VHIRD) were analyzed, as well as the number of efforts between 21 and 24 km h-1 (Sp21) and > 24 km h-1 (Sp24). Seasons were divided into four phases (P): P1 (matches 1-10), P2 (11-19), P3 (20-29), and P4 (30-38). Linear mixed models revealed that soccer players covered significantly greater distances and completed a higher number of sprints in P2 and P3. Also, team performance evaluated by soccer coaches was positively related to TD, HIRD, VHIRD and Sp21 in P1. A negative relationship was observed between team performance and distance covered at speeds below 21 km h-1 in P2 and P3. Team performance was negatively related to TD, MIRD, and HIRD, and Sp21 in P4. As conclusion, the team performance perceived by coaches is related to the movement profile throughout a season, and it significantly influences the evolution of soccer players' movement profiles. Specifically, it seems that the players of the best teams have the best physical performance at the beginning of the season with respect to the rest of the phases.

No effect of the Penalty Point System on road traffic accident mortality among men with a high socioeconomic status in Spain.

The purpose of this study was to assess the effect of the Penalty Point System (PPS) on road traffic accident mortality by gender and socioeconomic status. We conducted a nationwide prospective study covering adult people living in Spain on November 2001. They were followed up until 30 Nov 2007 to determine vital status and cause of death. An interrupted time-series analysis was used to assess whether PPS (explanatory variable) had both immediate and long-term effect on the rates of road traffic accident mortality (RTAMs) separately by gender. Subjects were classified by socioeconomic status (low and high) using two indicators: educational attainment (up to lower secondary education; upper secondary education or more) and occupation (manual and non-manual workers). We performed several segmented Poisson regression models, controlling for trend, seasonality, 2004 road safety measures and fuel consumption as proxy for traffic exposure. Among men, we found a decrease on the RTAMs immediately after PPS in those with low educational level (16.2 %, IC95 %: 6.1 %-25.2 %) and manual workers (16.3 %, IC95 %: 2.8 %-27.8 %), and a non-significant increase among those with high education level and non-manual workers (6.2 % and 1.8 %). Among women, there were no significant differences in the immediate effect of PPS by socioeconomic status. We did not identify significant trend changes between pre-PPS and post-PPS periods in any socioeconomic group. In a context of downward trend of traffic mortality, the PPS implementation led to an immediate reduction on death rates only among men with a low socioeconomic status.

Long-term impact of the 2008 economic crisis in Spain on road traffic collisions mortality by socioeconomic position.

We aimed to assess the effect of the 2008 crisis on road traffic collision (RTC) mortality in Spain, by socioeconomic position (SEP) and type of road use. This prospective, country-wide study covered all adults living in Spain and aged ≥30 years in November 2001. The long-term effect of the crisis was assessed by measuring the monthly percentage change (MPC) in RTC mortality between the pre-crisis (2002-2007) and crisis period (2008-2011). During the recession, RTC mortality fell more in people with low compared to high SEP, so MPCs difference between periods were of a higher magnitude in the low compared to high SEP groups, especially among men motorcyclists. RTC mortality trends were favorable following the 2008 crisis, particularly among low-SEP groups. In men motorcyclists, the upward trend of the pre-crisis period reversed course.

Deep learning systems detect dysplasia with human-like accuracy using histopathology and probe-based confocal laser endomicroscopy.

Probe-based confocal laser endomicroscopy (pCLE) allows for real-time diagnosis of dysplasia and cancer in Barrett's esophagus (BE) but is limited by low sensitivity. Even the gold standard of histopathology is hindered by poor agreement between pathologists. We deployed deep-learning-based image and video analysis in order to improve diagnostic accuracy of pCLE videos and biopsy images. Blinded experts categorized biopsies and pCLE videos as squamous, non-dysplastic BE, or dysplasia/cancer, and deep learning models were trained to classify the data into these three categories. Biopsy classification was conducted using two distinct approaches-a patch-level model and a whole-slide-image-level model. Gradient-weighted class activation maps (Grad-CAMs) were extracted from pCLE and biopsy models in order to determine tissue structures deemed relevant by the models. 1970 pCLE videos, 897,931 biopsy patches, and 387 whole-slide images were used to train, test, and validate the models. In pCLE analysis, models achieved a high sensitivity for dysplasia (71%) and an overall accuracy of 90% for all classes. For biopsies at the patch level, the model achieved a sensitivity of 72% for dysplasia and an overall accuracy of 90%. The whole-slide-image-level model achieved a sensitivity of 90% for dysplasia and 94% overall accuracy. Grad-CAMs for all models showed activation in medically relevant tissue regions. Our deep learning models achieved high diagnostic accuracy for both pCLE-based and histopathologic diagnosis of esophageal dysplasia and its precursors, similar to human accuracy in prior studies. These machine learning approaches may improve accuracy and efficiency of current screening protocols.

A knowledge-based taxonomy of critical factors for adopting electronic health record systems by physicians: a systematic literature review.

BACKGROUND: The health care sector is an area of social and economic interest in several countries; therefore, there have been lots of efforts in the use of electronic health records. Nevertheless, there is evidence suggesting that these systems have not been adopted as it was expected, and although there are some proposals to support their adoption, the proposed support is not by means of information and communication technology which can provide automatic tools of support. The aim of this study is to identify the critical adoption factors for electronic health records by physicians and to use them as a guide to support their adoption process automatically. METHODS: This paper presents, based on the PRISMA statement, a systematic literature review in electronic databases with adoption studies of electronic health records published in English. Software applications that manage and process the data in the electronic health record have been considered, i.e.: computerized physician prescription, electronic medical records, and electronic capture of clinical data. Our review was conducted with the purpose of obtaining a taxonomy of the physicians main barriers for adopting electronic health records, that can be addressed by means of information and communication technology; in particular with the information technology roles of the knowledge management processes. Which take us to the question that we want to address in this work: "What are the critical adoption factors of electronic health records that can be supported by information and communication technology?". Reports from eight databases covering electronic health records adoption studies in the medical domain, in particular those focused on physicians, were analyzed. RESULTS: The review identifies two main issues: 1) a knowledge-based classification of critical factors for adopting electronic health records by physicians; and 2) the definition of a base for the design of a conceptual framework for supporting the design of knowledge-based systems, to assist the adoption process of electronic health records in an automatic fashion. From our review, six critical adoption factors have been identified: user attitude towards information systems, workflow impact, interoperability, technical support, communication among users, and expert support. The main limitation of the taxonomy is the different impact of the adoption factors of electronic health records reported by some studies depending on the type of practice, setting, or attention level; however, these features are a determinant aspect with regard to the adoption rate for the latter rather than the presence of a specific critical adoption factor. CONCLUSIONS: The critical adoption factors established here provide a sound theoretical basis for research to understand, support, and facilitate the adoption of electronic health records to physicians in benefit of patients.

SCREENING FOR BARRETT'S ESOPHAGUS WITH PROBE-BASED CONFOCAL LASER ENDOMICROSCOPY VIDEOS.

Histologic diagnosis of Barrett's esophagus and esophageal malignancy via probe-based confocal laser endomicroscopy (pCLE) allows for real-time examination of epithelial architecture and targeted biopsy sampling. Although pCLE demonstrates high specificity, sensitivity remains low. This study employs deep learning architectures in order to improve the accuracy of pCLE in diagnosing esophageal cancer and its precursors. pCLE videos are curated and annotated as belonging to one of the three classes: squamous, Barrett's (intestinal metaplasia without dysplasia), or dysplasia. We introduce two novel video architectures, AttentionPooling and Multi-Module AttentionPooling deep networks, that outperform other models and demonstrate a high degree of explainability.

Semi-Supervised Classification of Noisy, Gigapixel Histology Images.

One of the greatest obstacles in the adoption of deep neural networks for new medical applications is that training these models typically require a large amount of manually labeled training samples. In this body of work, we investigate the semi-supervised scenario where one has access to large amounts of unlabeled data and only a few labeled samples. We study the performance of MixMatch and FixMatch-two popular semi-supervised learning methods-on a histology dataset. More specifically, we study these models' impact under a highly noisy and imbalanced setting. The findings here motivate the development of semi-supervised methods to ameliorate problems commonly encountered in medical data applications.

Relationship between the average slope in the active commuting to and from school and fitness in adolescents: the mediator role of fatness.

Active commuting to and from school (ACS) has been recognized as a potential tool to improve physical fitness. Thus, this study aims to test the relationships between the average slope in the ACS and physical fitness, as well as to verify the mediator role of fatness in the relationship between average slope and physical fitness. A total of 257 participants, 137 boys and 120 girls, from 22 schools belonged to first and second High School grades participated in this study. Based on self-reported measure and Google Earth, participants were grouped into the active commuter (number of trips was ≥5, and the time of the trip was ≥15 min), mixed commuter (number of weekly trips was <5, and the time spent on the trip was <15 min) and passive commuter groups (those who reported traveling regularly by car, motorcycle, or bus). Specifically, in the active commuter group, a positive association between the average slope in the ACS with fatness was found, which in turn was positively related to strength lower limbs and cardiorrespiratory fitness. The average slope was not significantly associated with physical fitness indicators. Furtheremore, fatness did not mediate the relathionship between average slope and physical fitness. This research concluded positive associations between average slope and the body fat in the ACS. The tendency of findings signal that the average slope should be taken into account along with the distance, time and frequency of the active commuting.