TY - JOUR A1 - Quarmby, Andrew James A1 - Khajooei, Mina A1 - Kurtz, Philip A1 - Henschke, Jakob A1 - Kim, MyoungHwee A1 - Mayer, Frank A1 - Engel, Tilman T1 - Unexpected running perturbations BT - reliability and validity of a treadmill running protocol with analysis of provoked reflex activity in the lower extremities JF - Frontiers in sports and active living N2 - Introduction Balance is vital for human health and experiments have been conducted to measure the mechanisms of postural control, for example studying reflex responses to simulated perturbations. Such studies are frequent in walking but less common in running, and an understanding of reflex responses to trip-like disturbances could enhance our understanding of human gait and improve approaches to training and rehabilitation. Therefore, the primary aim of this study was to investigate the technical validity and reliability of a treadmill running protocol with perturbations. A further exploratory aim was to evaluate the associated neuromuscular reflex responses to the perturbations, in the lower limbs. Methods Twelve healthy participants completed a running protocol (9 km/h) test-retest (2 weeks apart), whereby 30 unilateral perturbations were executed via the treadmill belts (presets:2.0 m/s amplitude;150 ms delay (post-heel contact);100ms duration). Validity of the perturbations was assessed via mean +/- SD comparison, percentage error calculation between the preset and recorded perturbation characteristics (PE%), and coefficient of variation (CV%). Test-retest reliability (TRV%) and Bland-Altman analysis (BLA; bias +/- 1.96 * SD) was calculated for reliability. To measure reflex activity, electromyography (EMG) was applied in both legs. EMG amplitudes (root mean square normalized to unperturbed strides) and latencies [ms] were analysed descriptively. Results Left-side perturbation amplitude was 1.9 +/- 0.1 m/s, delay 105 +/- 2 ms, and duration 78 +/- 1 ms. Right-side perturbation amplitude was 1.9 +/- 0.1 m/s, delay 118 +/- 2 ms, duration 78 +/- 1 ms. PE% ranged from 5-30% for the recorded perturbations. CV% of the perturbations ranged from 19.5-76.8%. TRV% for the perturbations was 6.4-16.6%. BLA for the left was amplitude: 0.0 +/- 0.3m/s, delay: 0 +/- 17 ms, duration: 2 +/- 13 ms, and for the right was amplitude: 0.1 +/- 0.7, delay: 4 +/- 40 ms, duration: 1 +/- 35 ms. EMG amplitudes ranged from 175 +/- 141%-454 +/- 359% in both limbs. Latencies were 109 +/- 12-116 +/- 23 ms in the tibialis anterior, and 128 +/- 49-157 +/- 20 ms in the biceps femoris. Discussion Generally, this study indicated sufficient validity and reliability of the current setup considering the technical challenges and limitations, although the reliability of the right-sided perturbations could be questioned. The protocol provoked reflex responses in the lower extremities, especially in the leading leg. Acute neuromusculoskeletal adjustments to the perturbations could be studied and compared in clinical and healthy running populations, and the protocol could be utilised to monitor chronic adaptations to interventions over time. KW - running KW - perturbation KW - EMG KW - reliability KW - stumbling KW - reflexes KW - split-belt treadmill KW - gait Y1 - 2023 U6 - https://doi.org/10.3389/fspor.2023.1129058 SN - 2624-9367 VL - 5 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Busch, Aglaja A1 - Bangerter, Christian A1 - Mayer, Frank A1 - Baur, Heiner T1 - Reliability of the active knee joint position sense test and influence of limb dominance and sex JF - Scientific reports N2 - The output of a sensorimotor performance can be measured with the joint position sense (JPS) test. However, investigations of leg dominance, sex and quality measures on this test are limited. Therefore, these potential influencing factors as well as reliability and consistency measures were evaluated for angular reproduction performance and neuromuscular activity during the active knee JPS test in healthy participants. Twenty healthy participants (10 males; 10 females; age 29 +/- 8 years; height 165 +/- 39 cm; body mass 69 +/- 13 kg) performed a seated knee JPS test with a target angle of 50 degrees. Measurements were conducted in two sessions separated by two weeks and consisted of two blocks of continuous angular reproduction (three minutes each block). The difference between reproduced and target angle was identified as angular error measured by an electrogoniometer. During reproduction, the neuromuscular activity of the quadriceps muscle was assessed by surface electromyography. Neuromuscular activity was normalized to submaximal voluntary contraction (subMVC) and displayed per muscle and movement phase. Differences between leg dominance and sex were calculated using Friedman-test (alpha = 0.05). Reliability measures including intraclass correlation coefficient (ICC), Bland-Altman analysis (bias +/- limits of agreement (LoA)) and minimal detectable change (MDC) were analysed. No significant differences between leg dominance and sex were found in angular error and neuromuscular activity. Angular error demonstrated inter-session ICC scores of 0.424 with a bias of 2.4 degrees (+/- 2.4 degrees LoA) as well as MDC of 6.8 degrees and moderate intra-session ICC (0.723) with a bias of 1.4 degrees (+/- 1.65 degrees LoA) as well as MDC of 4.7 degrees. Neuromuscular activity for all muscles and movement phases illustrated inter-session ICC ranging from 0.432 to 0.809 with biases between - 2.5 and 13.6% subMVC and MDC from 13.4 to 63.9% subMVC. Intra-session ICC ranged from 0.705 to 0.987 with biases of - 7.7 to 2.4% subMVC and MDC of 2.7 to 46.5% subMVC. Leg dominance and sex seem not to influence angular reproduction performance and neuromuscular activity. Poor to excellent relative reliability paired with an acceptable consistency confirm findings of previous studies. Comparisons to pathological populations should be conducted with caution. Y1 - 2023 U6 - https://doi.org/10.1038/s41598-022-26932-2 SN - 2045-2322 VL - 13 PB - Macmillan Publishers Limited, part of Springer Nature CY - London ER - TY - JOUR A1 - Lin, Chiao-I A1 - Mayer, Frank A1 - Wippert, Pia-Maria T1 - The prevalence of chronic ankle instability in basketball athletes: a cross-sectional study JF - BMC Sports Science, Medicine and Rehabilitation N2 - Background Ankle sprain is the most common injury in basketball. Chronic ankle instability develops from an acute ankle sprain may cause negative effects on quality of life, ankle functionality or on increasing risk for recurrent ankle sprains and post-traumatic osteoarthritis. To facilitate a preventative strategy of chronic ankle instability (CAI) in the basketball population, gathering epidemiological data is essential. However, the epidemiological data of CAI in basketball is limited. Therefore, this study aims to investigate the prevalence of CAI in basketball athletes and to determine whether gender, competitive level, and basketball playing position influence this prevalence. Methods In a cross-sectional study, in total 391 Taiwanese basketball athletes from universities and sports clubs participated. Besides non-standardized questions about demographics and their history of ankle sprains, participants further filled out the standard Cumberland Ankle Instability Tool applied to determine the presence of ankle instability. Questionnaires from 255 collegiate and 133 semi-professional basketball athletes (male = 243, female = 145, 22.3 ± 3.8 years, 23.3 ± 2.2 kg/m2) were analyzed. Differences in prevalence between gender, competitive level and playing position were determined using the Chi-square test. Results In the surveyed cohort, 26% had unilateral CAI while 50% of them had bilateral CAI. Women had a higher prevalence than men in the whole surveyed cohort (X2(1) = 0.515, p = 0.003). This gender disparity also showed from sub-analyses, that the collegiate female athletes had a higher prevalence than collegiate men athletes (X2(1) = 0.203, p = 0.001). Prevalence showed no difference between competitive levels (p > 0.05) and among playing positions (p > 0.05). Conclusions CAI is highly prevalent in the basketball population. Gender affects the prevalence of CAI. Regardless of the competitive level and playing position the prevalence of CAI is similar. The characteristic of basketball contributes to the high prevalence. Prevention of CAI should be a focus in basketball. When applying the CAI prevention measures, gender should be taken into consideration. KW - Functional ankle instability KW - Perceived ankle instability KW - Ankle sprain KW - Ankle injury KW - Survey KW - Basketball Y1 - 2022 U6 - https://doi.org/10.1186/s13102-022-00418-0 SN - 2052-1847 VL - 14 SP - 1 EP - 9 PB - BioMed Central Ltd CY - London ER - TY - JOUR A1 - Mueller, Steffen A1 - Mueller, Juliane A1 - Stoll, Josefine A1 - Mayer, Frank T1 - Effect of six-week resistance and sensorimotor training on trunk strength and stability in elite adolescent athletes BT - a randomized controlled pilot trial JF - Frontiers in physiology N2 - Intervention in the form of core-specific stability exercises is evident to improve trunk stability. The purpose was to assess the effect of an additional 6 weeks sensorimotor or resistance training on maximum isokinetic trunk strength and response to sudden dynamic trunk loading (STL) in highly trained adolescent athletes. The study was conducted as a single-blind, 3-armed randomized controlled trial. Twenty-four adolescent athletes (14f/10 m, 16 +/- 1 yrs.;178 +/- 10 cm; 67 +/- 11 kg; training sessions/week 15 +/- 5; training h/week 22 +/- 8) were randomized into resistance training (RT; n = 7), sensorimotor training (SMT; n = 10), and control group (CG; n = 7). Athletes were instructed to perform standardized, center-based training for 6 weeks, two times per week, with a duration of 1 h each session. SMT consisted of four different core-specific sensorimotor exercises using instable surfaces. RT consisted of four trunk strength exercises using strength training machines, as well as an isokinetic dynamometer. All participants in the CG received an unspecific heart frequency controlled, ergometer-based endurance training (50 min at max. heart frequency of 130HF). For each athlete, each training session was documented in an individual training diary (e.g., level of SMT exercise; 1RM for strength exercise, pain). At baseline (M1) and after 6 weeks of intervention (M2), participants' maximum strength in trunk rotation (ROM:63 degrees) and flexion/extension (ROM:55 degrees) was tested on an isokinetic dynamometer (concentric/eccentric 30 degrees/s). STL was assessed in eccentric (30 degrees/s) mode with additional dynamometer-induced perturbation as a marker of core stability. Peak torque [Nm] was calculated as the main outcome. The primary outcome measurements (trunk rotation/extension peak torque: con, ecc, STL) were statistically analyzed by means of the two-factor repeated measures analysis of variance (alpha = 0.05). Out of 12 possible sessions, athletes participated between 8 and 9 sessions (SMT: 9 +/- 3; RT: 8 +/- 3; CG: 8 +/- 4). Regarding main outcomes of trunk performance, experimental groups showed no significant pre-post difference for maximum trunk strength testing as well as for perturbation compensation (p > 0.05). It is concluded, that future interventions should exceed 6 weeks duration with at least 2 sessions per week to induce enhanced trunk strength or compensatory response to sudden, high-intensity trunk loading in already highly trained adolescent athletes, regardless of training regime. KW - core KW - training intervention KW - trunk stability KW - exercise KW - perturbation Y1 - 2022 U6 - https://doi.org/10.3389/fphys.2022.802315 SN - 1664-042X VL - 13 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Lin, Chiao-I A1 - Mayer, Frank A1 - Wippert, Pia-Maria T1 - The prevalence of chronic ankle instability in basketball athletes BT - a cross-sectional study JF - BMC sports science, medicine & rehabilitation N2 - Background Ankle sprain is the most common injury in basketball. Chronic ankle instability develops from an acute ankle sprain may cause negative effects on quality of life, ankle functionality or on increasing risk for recurrent ankle sprains and post-traumatic osteoarthritis. To facilitate a preventative strategy of chronic ankle instability (CAI) in the basketball population, gathering epidemiological data is essential. However, the epidemiological data of CAI in basketball is limited. Therefore, this study aims to investigate the prevalence of CAI in basketball athletes and to determine whether gender, competitive level, and basketball playing position influence this prevalence. Methods In a cross-sectional study, in total 391 Taiwanese basketball athletes from universities and sports clubs participated. Besides non-standardized questions about demographics and their history of ankle sprains, participants further filled out the standard Cumberland Ankle Instability Tool applied to determine the presence of ankle instability. Questionnaires from 255 collegiate and 133 semi-professional basketball athletes (male = 243, female = 145, 22.3 +/- 3.8 years, 23.3 +/- 2.2 kg/m(2)) were analyzed. Differences in prevalence between gender, competitive level and playing position were determined using the Chi-square test. Results In the surveyed cohort, 26% had unilateral CAI while 50% of them had bilateral CAI. Women had a higher prevalence than men in the whole surveyed cohort (X-2(1) = 0.515, p = 0.003). This gender disparity also showed from sub-analyses, that the collegiate female athletes had a higher prevalence than collegiate men athletes (X-2(1) = 0.203, p = 0.001). Prevalence showed no difference between competitive levels (p > 0.05) and among playing positions (p > 0.05). Conclusions CAI is highly prevalent in the basketball population. Gender affects the prevalence of CAI. Regardless of the competitive level and playing position the prevalence of CAI is similar. The characteristic of basketball contributes to the high prevalence. Prevention of CAI should be a focus in basketball. When applying the CAI prevention measures, gender should be taken into consideration. KW - Functional ankle instability KW - Perceived ankle instability KW - Ankle sprain; KW - Ankle injury KW - Survey KW - Basketball Y1 - 2022 U6 - https://doi.org/10.1186/s13102-022-00418-0 SN - 2052-1847 VL - 14 IS - 1 PB - BMC CY - London ER - TY - JOUR A1 - Wochatz, Monique A1 - Schraplau, Anne A1 - Engel, Tilman A1 - Zecher, Mahli Megan A1 - Sharon, Hadar A1 - Alt, Yasmin A1 - Mayer, Frank A1 - Kalron, Alon T1 - Application of eccentric training in various clinical populations BT - Protocol for a multi-centered pilot and feasibility study in people with low back pain and people with multiple sclerosis JF - PLoS ONE N2 - Physical activity and exercise are effective approaches in prevention and therapy of multiple diseases. Although the specific characteristics of lengthening contractions have the potential to be beneficial in many clinical conditions, eccentric training is not commonly used in clinical populations with metabolic, orthopaedic, or neurologic conditions. The purpose of this pilot study is to investigate the feasibility, functional benefits, and systemic responses of an eccentric exercise program focused on the trunk and lower extremities in people with low back pain (LBP) and multiple sclerosis (MS). A six-week eccentric training program with three weekly sessions is performed by people with LBP and MS. The program consists of ten exercises addressing strength of the trunk and lower extremities. The study follows a four-group design (N = 12 per group) in two study centers (Israel and Germany): three groups perform the eccentric training program: A) control group (healthy, asymptomatic); B) people with LBP; C) people with MS; group D (people with MS) receives standard care physiotherapy. Baseline measurements are conducted before first training, post-measurement takes place after the last session both comprise blood sampling, self-reported questionnaires, mobility, balance, and strength testing. The feasibility of the eccentric training program will be evaluated using quantitative and qualitative measures related to the study process, compliance and adherence, safety, and overall program assessment. For preliminary assessment of potential intervention effects, surrogate parameters related to mobility, postural control, muscle strength and systemic effects are assessed. The presented study will add knowledge regarding safety, feasibility, and initial effects of eccentric training in people with orthopaedic and neurological conditions. The simple exercises, that are easily modifiable in complexity and intensity, are likely beneficial to other populations. Thus, multiple applications and implementation pathways for the herein presented training program are conceivable. Y1 - 2022 U6 - https://doi.org/10.1371/journal.pone.0270875 SN - 1932-6203 VL - 17 IS - 12 PB - Public Library of Science CY - San Francisco, California, USA ER - TY - JOUR A1 - Schraplau, Anne A1 - Block, Andrea A1 - Häusler, Andreas A1 - Wippert, Pia-Maria A1 - Rapp, Michael A. A1 - Völler, Heinz A1 - Bonaventura, Klaus A1 - Mayer, Frank T1 - Mobile diagnostics and consultation for the prevention of the metabolic syndrome and its secondary diseases in Brandenburg—study protocol of a regional prospective cohort study BT - the Mobile Brandenburg Cohort JF - Pilot and Feasibility Studies N2 - Background The metabolic syndrome (MetS) is a risk cluster for a number of secondary diseases. The implementation of prevention programs requires early detection of individuals at risk. However, access to health care providers is limited in structurally weak regions. Brandenburg, a rural federal state in Germany, has an especially high MetS prevalence and disease burden. This study aims to validate and test the feasibility of a setup for mobile diagnostics of MetS and its secondary diseases, to evaluate the MetS prevalence and its association with moderating factors in Brandenburg and to identify new ways of early prevention, while establishing a “Mobile Brandenburg Cohort” to reveal new causes and risk factors for MetS. Methods In a pilot study, setups for mobile diagnostics of MetS and secondary diseases will be developed and validated. A van will be equipped as an examination room using point-of-care blood analyzers and by mobilizing standard methods. In study part A, these mobile diagnostic units will be placed at different locations in Brandenburg to locally recruit 5000 participants aged 40-70 years. They will be examined for MetS and advice on nutrition and physical activity will be provided. Questionnaires will be used to evaluate sociodemographics, stress perception, and physical activity. In study part B, participants with MetS, but without known secondary diseases, will receive a detailed mobile medical examination, including MetS diagnostics, medical history, clinical examinations, and instrumental diagnostics for internal, cardiovascular, musculoskeletal, and cognitive disorders. Participants will receive advice on nutrition and an exercise program will be demonstrated on site. People unable to participate in these mobile examinations will be interviewed by telephone. If necessary, participants will be referred to general practitioners for further diagnosis. Discussion The mobile diagnostics approach enables early detection of individuals at risk, and their targeted referral to local health care providers. Evaluation of the MetS prevalence, its relation to risk-increasing factors, and the “Mobile Brandenburg Cohort” create a unique database for further longitudinal studies on the implementation of home-based prevention programs to reduce mortality, especially in rural regions. Trial registration German Clinical Trials Register, DRKS00022764; registered 07 October 2020—retrospectively registered. KW - Metabolic syndrome KW - Mobile diagnostics KW - Prevention KW - Nutrition KW - Physical activity KW - Rural health Y1 - 2021 U6 - https://doi.org/10.1186/s40814-021-00898-w SN - 2055-5784 VL - 7 SP - 1 EP - 11 PB - BioMed Central (Springer Nature) CY - London ER - TY - JOUR A1 - Lin, Chiao-I A1 - Houtenbos, Sanne A1 - Lu, Yu-Hsien A1 - Mayer, Frank A1 - Wippert, Pia-Maria T1 - The epidemiology of chronic ankle instability with perceived ankle instability BT - a systematic review JF - Journal of foot and ankle research / Australasian Podiatry Council; Society of Chiropodists and Podiatrists (UK) N2 - Background: Chronic ankle instability, developing from ankle sprain, is one of the most common sports injuries. Besides it being an ankle issue, chronic ankle instability can also cause additional injuries. Investigating the epidemiology of chronic ankle instability is an essential step to develop an adequate injury prevention strategy. However, the epidemiology of chronic ankle instability remains unknown. Therefore, the purpose of this study was to investigate the epidemiology of chronic ankle instability through valid and reliable self-reported tools in active populations. Methods: An electronic search was performed on PubMed and Web of Science in July 2020. The inclusion criteria for articles were peer-reviewed, published between 2006 and 2020, using one of the valid and reliable tools to evaluate ankle instability, determining chronic ankle instability based on the criteria of the International Ankle Consortium, and including the outcome of epidemiology of chronic ankle instability. The risk of bias of the included studies was evaluated with an adapted tool for the sports injury review method. Results: After removing duplicated studies, 593 articles were screened for eligibility. Twenty full-texts were screened and finally nine studies were included, assessing 3804 participants in total. The participants were between 15 and 32 years old and represented soldiers, students, athletes and active individuals with a history of ankle sprain. The prevalence of chronic ankle instability was 25%, ranging between 7 and 53%. The prevalence of chronic ankle instability within participants with a history of ankle sprains was 46%, ranging between 9 and 76%. Five included studies identified chronic ankle instability based on the standard criteria, and four studies applied adapted exclusion criteria to conduct the study. Five out of nine included studies showed a low risk of bias. Conclusions: The prevalence of chronic ankle instability shows a wide range. This could be due to the different exclusion criteria, age, sports discipline, or other factors among the included studies. For future studies, standardized criteria to investigate the epidemiology of chronic ankle instability are required. The epidemiology of CAI should be prospective. Factors affecting the prevalence of chronic ankle instability should be investigated and clearly described. KW - Ankle sprain KW - Sports injury KW - Functional ankle instability Y1 - 2020 U6 - https://doi.org/10.1186/s13047-021-00480-w SN - 1757-1146 VL - 14 PB - BioMed Central CY - London ER - TY - JOUR A1 - Engel, Tilman A1 - Schraplau, Anne A1 - Wochatz, Monique A1 - Kopinski, Stephan A1 - Sonnenburg, Dominik A1 - Schomöller, Anne A1 - Risch, Lucie A1 - Kaplick, Hannes A1 - Mayer, Frank T1 - Feasability of An Eccentric Isokinetic Protocol to Induce Trunk Muscle Damage: A Pilot Study JF - Sports Medicine International Open N2 - Eccentric exercise is discussed as a treatment option for clinical populations, but specific responses in terms of muscle damage and systemic inflammation after repeated loading of large muscle groups have not been conclusively characterized. Therefore, this study tested the feasibility of an isokinetic protocol for repeated maximum eccentric loading of the trunk muscles. Nine asymptomatic participants (5 f/4 m; 34±6 yrs; 175±13 cm; 76±17 kg) performed three isokinetic 2-minute all-out trunk strength tests (1x concentric (CON), 2x eccentric (ECC1, ECC2), 2 weeks apart; flexion/extension, 60°/s, ROM 55°). Outcomes were peak torque, torque decline, total work, and indicators of muscle damage and inflammation (over 168 h). Statistics were done using the Friedman test (Dunn’s post-test). For ECC1 and ECC2, peak torque and total work were increased and torque decline reduced compared to CON. Repeated ECC bouts yielded unaltered torque and work outcomes. Muscle damage markers were highest after ECC1 (soreness 48 h, creatine kinase 72 h; p<0.05). Their overall responses (area under the curve) were abolished post-ECC2 compared to post-ECC1 (p<0.05). Interleukin-6 was higher post-ECC1 than CON, and attenuated post-ECC2 (p>0.05). Interleukin-10 and tumor necrosis factor-α were not detectable. All markers showed high inter-individual variability. The protocol was feasible to induce muscle damage indicators after exercising a large muscle group, but the pilot results indicated only weak systemic inflammatory responses in asymptomatic adults. KW - exercise KW - eccentric KW - muscle fatigue KW - trunk muscles KW - isokinetics KW - repeated bout effect KW - inflammation KW - exercise induced muscle damage KW - interleukin-6 KW - internleukin-10 KW - tumor necrosis factor-α Y1 - 2021 U6 - https://doi.org/10.1055/a-1757-6724 SN - 2367-1890 VL - 6 SP - E9 EP - E17 PB - Thieme CY - Stuttgart ET - 1 ER - TY - JOUR A1 - Wochatz, Monique A1 - Rabe, Sophie A1 - Engel, Tilman A1 - Müller, Steffen A1 - Mayer, Frank T1 - Scapular kinematics during unloaded and maximal loaded isokinetic concentric and eccentric shoulder flexion and extension movements JF - Journal of electromyography & kinesiology : official journal of the International Society of Electrophysiology and Kinesiology N2 - Characterization of scapular kinematics under demanding load conditions might aid to distinguish between physiological and clinically relevant alterations. Previous investigations focused only on submaximal external load situations. How scapular movement changes with maximal load remains unclear. Therefore, the present study aimed to evaluate 3D scapular kinematics during unloaded and maximal loaded shoulder flexion and extension. Twelve asymptomatic individuals performed shoulder flexion and extension movements under unloaded and maximal concentric and eccentric loaded isokinetic conditions. 3D scapular kinematics assessed with a motion capture system was analyzed for 20° intervals of humeral positions from 20° to 120° flexion. Repeated measures ANOVAs were used to evaluate kinematic differences between load conditions for scapular position angles, scapulohumeral rhythm and scapular motion extent. Increased scapular upward rotation was seen during shoulder flexion and extension as well as decreased posterior tilt and external rotation during eccentric and concentric arm descents of maximal loaded compared to unloaded conditions. Load effects were further seen for the scapulohumeral rhythm with greater scapular involvement at lower humeral positions and increased scapular motion extent under maximal loaded shoulder movements. With maximal load applied to the arm physiological scapular movement pattern are induced that may imply both impingement sparing and causing mechanisms. KW - Isokinetics KW - Motion analysis KW - Scapular dyskinesis KW - Scapulohumeral rhythm KW - Scapulothoracic Y1 - 2020 U6 - https://doi.org/10.1016/j.jelekin.2021.102517 SN - 1050-6411 SN - 1873-5711 VL - 57 PB - Elsevier CY - Amsterdam ER -