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OBJECTIVE: This study aims to develop and evaluate a simple tool for daily practice that might allow a rough estimate of individual braking performance (brake response time, BRT) of patients with osteoarthritis or those with arthroplasty of the knee or hip. METHODS: In this cross-sectional study, we examined 162 patients (72 men, 90 women; mean age = 64±12.8 years) who suffered from osteoarthritis of the knee (n=45) or hip (n=64) or who underwent a total hip (n=37) or knee (n=16) arthroplasty. BRT of each patient was measured in a brake simulator. The results were compared to demographic data, various clinical tests, and pain surveys. From these data, a multiple linear regression model was developed. RESULTS: From the observed correlations, the regression model consisted of age (correlation with BRT τ=0.176, p=0.001), sex (τ=0.361, p

Traditionally, machine milking is performed at a constant vacuum supply. The system vacuum has to be set high enough to allow a sufficiently high vacuum at the teat end, despite the inevitable vacuum drop caused by milk flow. This leads to an increased vacuum load on the teat, especially when milk flow ceases at the end of milking. We tested the hypothesis that a milk flow-controlled adaptation of vacuum settings during milking allows even higher vacuum levels than are usually recommended during the period of high milk flow if the vacuum is reduced during low milk flow. Combined with a high cluster detachment flow rate level, increased milking performance is expected without an increased effect on teat tissue. Ten Holstein dairy cows were milked with a bucket milker with the claw vacuum adjusted in the absence of milk flow at a regular (43 kPa) and high (48 kPa) claw vacuum, with and without vacuum reduction during low milk flow (

In systems biology, biological phenomena are often modeled by Ordinary Differential Equations (ODEs) and distributed in the de facto standard file format SBML. The primary analyses performed with such models are dynamic simulation, steady-state analysis, and parameter estimation. These methodologies are mathematically formalized, and libraries for such analyses have been published. Several tools exist to create, simulate, or visualize models encoded in SBML. However, setting up and establishing analysis environments is a crucial hurdle for non-modelers. Therefore, easy access to perform fundamental analyses of ODE models is a significant challenge. We developed SBMLWebApp, a web-based service to execute SBML-based simulation, steady-state analysis, and parameter estimation directly in the browser without the need for any setup or prior knowledge to address this issue. SBMLWebApp visualizes the result and numerical table of each analysis and provides a download of the results. SBMLWebApp allows users to select and analyze SBML models directly from the BioModels Database. Taken together, SBMLWebApp provides barrier-free access to an SBML analysis environment for simulation, steady-state analysis, and parameter estimation for SBML models. SBMLWebApp is implemented in Java™ based on an Apache Tomcat® web server using COPASI, the Systems Biology Simulation Core Library (SBSCL), and LibSBMLSim as simulation engines. SBMLWebApp is licensed under MIT with source code freely available. At the end of this article, the Data Availability Statement gives the internet links to the two websites to find the source code and run the program online.

Intervertebral disc (IVD) degeneration is a leading cause of low back pain and it entails a high degree of impairment for the affected individuals. To decode disc degeneration and to be able to develop regenerative approaches a thorough understanding of the cellular biology of the IVD is essential. One aspect of this biology that still remains unanswered is the question of how cells are spatially arranged in a physiological state and during degeneration. The biological properties of the IVD and its availability make this tissue difficult to analyze. The present study investigates spatial chondrocyte organization in the anulus fibrosus from early embryonic development to end-stage degeneration. An optical sectioning method (Apotome) is applied to perform high resolution staining analyses using bovine embryonic tissue as an animal model and human disc tissue obtained from patients undergoing spine surgery. From a very high chondrocyte density in the early embryonic bovine disc, the number of cells decreases during gestation, growth, and maturation. In human discs, an increase in cellular density accompanied the progression of tissue degeneration. As had already been demonstrated in articular cartilage, cluster formation represents a characteristic feature of advanced disc degeneration.

Even though it is widely believed that cross-modal neuroplasticity in blindness results in enhanced auditory spatial abilities, a growing number of studies also indicate disadvantages of blind persons for specific, more demanding audiospatial tasks. Here, the effects of blindness on horizontal sound localization were compared for simple localization of target sounds presented in isolation and target localization in an acoustically complex ( cocktail-party) situation with multiple distractor sounds. While performances of blind and sighted subjects were similar in the cocktail-party setting, a significant disadvantage of blind subjects was found for simple localization of sound sources presented in the center of the frontal space, with the mean absolute error being more than twice that of controls for targets in the median plane. The latter result could be due to the lack of visual calibration of auditory space, which may, in sighted persons, be most effective in the region of maximum visual acuity. On the other hand, the normal performance of blind persons in cocktail-party localization could be explained by the fact that this task, in addition to genuine spatial analysis, critically involved spectrotemporal analysis of the auditory scene to separate different sources for which superior performance is known from previous research.

OBJECTIVE To investigate if testing in a brake simulator can be replaced by a simple reaction timer setup imitating the ergonomic conditions of emergency braking when evaluating the ability to drive in patients with musculoskeletal problems of the lower extremities. METHODS A cross-sectional survey was performed in the Department of Orthopaedic Surgery in our University Hospital from October 2014 until May 2015. Patients attending our department with either osteoarthritis or arthroplasty of the knee or hip were asked to participate in the study if they had a valid driving license. The age limit was from 18 to 85 years. Both women and men were included. Registered demographic data were patient age, height, sex, body weight, and body mass index. Braking performance (brake response time [BRT]) was evaluated in a brake simulator that was embedded into a real car cabin (10 measurements). The values obtained were compared with those registered when simply testing (5 measurements) those patients with a normal reaction timer setup that imitated the sitting position in a car. Kendall's tau correlation coefficient was calculated between the values obtained from the brake simulator with those from the reaction timer setup. RESULTS Altogether, 137 patients (median age 67 years [range, 24-89 years]) with either osteoarthritis of the knee (n = 55) or hip (n = 82) were tested. Age was comparable in both collectives (P = 0.807). The mean body height was 1.70 m in both groups. Knee patients presented with a higher body weight of approximately 5 kg (P = 0.014) and consequently also had a higher body mass index (P = 0.023). The median BRT in the brake simulator was 628 ms (range, 390-1444 ms) for all subjects: 592 ms (range, 418-1146 ms) in the hip group and 696 ms (range, 390-1444 ms) in the knee group. Measurement values obtained by the reaction timer were significantly (P < 0.001) higher by approximately 15% (SD, 22%) than those measured in the brake simulator. A moderate correlation was found between the reaction timer and the brake simulator, with a Kendall's tau of 0.449 (P < 0.001) for all patients. Interestingly, hip patients showed a higher correlation (τ = 0.471) than knee patients (τ = 0.263). CONCLUSION Even though the measured correlations do not allow us to make a definite statement concerning braking performance, especially in knee patients, a simple reaction timer test can provide a low-cost first estimate of BRT for patients and their treating physicians. For forensic statements, the brake simulator will, however, remain the gold standard.

Background Spinal surgeries have strongly increased in number over the past decade. The question of when it is safe to resume driving is thereby one the most frequently asked questions that patients ask of their treating physician. Objective The aim of this study was to assess braking performance before and after spine surgery. Methods Reaction time, foot transfer time (together brake response time [BRT]), and brake force (BF) were evaluated in a drive simulator. A longitudinal patient cohort (n= 27) was tested preoperatively and at the first follow-up. A cross-sectional cohort (n= 27) was tested at > 1 year postoperatively. The values from these groups were compared with a healthy age-matched control group of 24 volunteers. Results No significant improvement in BRT was seen in lumbar fusion three months postoperatively (p= 0.597); BF was even weaker than it was preoperatively (p= 0.044). In comparison to the control group (median BRT 479 ms), preoperative BRT was already impaired in lumbar fusion patients (median 560 ms), representing an increased braking distance of 2.25 m at 100 km/h. Conclusion Although most patients performed adequately, about one third presented critical braking performance. Risk factors for impaired braking may include scheduled multisegmental fusion surgery, female sex, and pain.

Veterinary Record, 184 (10), ISSN:0042-4900

The question of whether patients with musculoskeletal disorders are fit to drive is of paramount importance for them and frequently is directed to the treating orthopedic specialist. Although perioperative braking performance has been increasingly investigated in recent years, scientific data on braking safety in individuals with osteoarthritis (OA) are scarce. This study analyzed the braking performance of 158 patients with OA of the right or left knee or hip and compared the results with radiographic OA grading according to the Kellgren-Lawrence classification scale. Reaction time and foot transfer time (together called brake response time [BRT]) and brake force were measured in a real car cabin, and the values were compared with measurements obtained from young (n=34) and age-matched (n=36) control groups. Although the majority of BRTs in both control groups remained below 600 milliseconds, patients with both hip and knee OA, whether on the right or left side, had significantly worse values ( P P =.92; Kendall tau for brake force: τ=−0.014, P =.82), which makes radiographs an inadequate tool for medical driving recommendations. [ Orthopedics. 2017; 40(1):e82–e89.]