| 1. |
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| 2. |
- Aidemark, Joakim, 1965, et al.
(författare)
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Experimental Dependability Evaluation of the Artk68-FT Real-time Kernel
- 2004
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Ingår i: Proc. of the International Conference on Real-Time and Embedded Computer Systems and Applications. ; , s. 625-645
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Konferensbidrag (refereegranskat)abstract
- This paper presents an experimental dependability evaluation of a small real-time kernel called Artk68-FT intended for distributed fault-tolerant real-time systems. A main goal of this research is to improve the dependabilityof such systems by using a two-level approach for tolerating transient faults. By providing mechanisms in the kernel for tolerating transient faults at the node level, the overall reliability is improved since the recovery time is much shorter at the node level than at the system level. Permanent faults and transient faults that cannot be handled at the node level have to be handled at the system level. The experimental evaluation was performed using fault injection experiments on the MC68340 microcontroller executing the kernel and three application tasks. The experimental results show that no wrong results were produced when faults were injected during execution of a critical task protected by Artk68-FT. Moreover, no application crashes were observed in the fault injection experiments with Artk68-FT compared to experiments with a version of the kernel without fault handling mechanisms.
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| 3. |
- Aidemark, Joakim, 1965, et al.
(författare)
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Experimental evaluation of time-redundant execution for a brake-by-wire application
- 2002
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Ingår i: International Conference on Dependable Systems and Networks, 2002. DSN 2002. Proceedings. - 0769511015 ; , s. 210-215
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Konferensbidrag (refereegranskat)abstract
- This paper presents an experimental evaluation of a brake-by-wire application that tolerates transient faults by temporal error masking. A specially designed real-time kernel that masks errors by triple time-redundant execution and voting executes the application on a fail-stop computer node. The objective is to reduce the number of node failures by masking errors at the computer node level. The real-time kernel always executes the application twice to detect errors, and ensures that a fail-stop failure occurs if there is not enough CPU-time available for a third execution and voting. Fault injection experiments show that temporal error masking reduced the number of fail-stop failures by 42% compared to executing the brake-by-wire task without time redundancy.
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| 4. |
- Aidemark, Joakim, 1965, et al.
(författare)
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On the probability of detecting data errors generated by permanent faults using time redundancy
- 2003
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Ingår i: Proceedings of the 9th IEEE International On-Line Testing Symposium, Kos, 7-9 July 2003. - 0769519687 ; , s. 68-74
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Konferensbidrag (refereegranskat)abstract
- Time redundant execution of tasks and comparison of results is a well-known technique for detecting transient faults in computer systems. However, time redundancy is also capable of detecting permanent faults that occur during or between the executions of two task replicas, provided the faults affect the results of the two tasks in different ways. In this paper, we derive an expression for estimating the probability of detecting data errors generated by permanent faults with time redundant execution. The expression is validated experimentally by injecting permanent stuck-at faults into a multiplier unit of a microprocessor. We use the derived expression to show how tasks can be scheduled to improve the detection probability of errors generated by permanent faults. We also show that the detection capability of permanent faults is low for the Temporal Error Masking (TEM) technique (i.e. triplicated execution and voting to mask transient faults) and may not be increased by scheduling. Thus, we propose complementing TEM with special test tasks.
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| 5. |
- Aidemark, Joakim, 1965, et al.
(författare)
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Path-Based Error Coverage Prediction
- 2002
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Ingår i: Journal of Electronic Testing: Theory and Applications (JETTA). - 1573-0727 .- 0923-8174. ; 18:3, s. 343-349
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Tidskriftsartikel (refereegranskat)abstract
- We present an analytical technique that uses fault injection data for estimating the coverage of concurrent error detection mechanisms in microprocessors. A major problem in such estimations is that the coverage depends on the program executed by the microprocessor as well as the input sequence to the program. We propose a method that predicts the error coverage for a specified input sequence based on fault injection data obtained for another input sequence. Our results show that post-injection analysis is a promising approach for reducing the cost of coverage estimation.
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| 6. |
- Arlat, Jean, et al.
(författare)
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Comparison of Physical and Software-Implemented Fault Injection Techniques
- 2003
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Ingår i: IEEE Transactions on Computers. - 0018-9340. ; 52:9, s. 1115-1133
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Tidskriftsartikel (refereegranskat)abstract
- This paper addresses the issue of characterizing the respective impact of fault injection techniques. Three physical techniques and one software-implemented technique that have been used to assess the fault tolerance features of the MARS fault-tolerant distributed real-time system are compared and analyzed. After a short summary of the fault tolerance features of the MARS architecture and especially of the error detection mechanisms that were used to compare the erroneous behaviors induced by the fault injection techniques considered, we describe the common distributed testbed and test scenario implemented to perform a coherent set of fault injection campaigns. The main features of the four fault injection techniques considered are then briefly described and the results obtained are finally presented and discussed. Emphasis is put on the analysis of the specific impact and merit of each injection technique.
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| 7. |
- Arlat, Jean, et al.
(författare)
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MEFISTO: A Series of Prototype Tools for Fault Injection into VHDL Models
- 2003
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Ingår i: Fault Injection Techniques and Tools for Embedded Systems Reliability Evaluation, Kluwer Academic Publishing. - 1402075898 ; , s. 177-193
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The early assessment of the fault tolerance mechanisms is an essential task in the design of dependable computing systems. Simulation languages offer the necessary support to carry out such a task. Due to its wide spectrum of application and hierarchical features, VHDL is a powerful simulation language. This chapter summarizes the main results of a pioneering effort aimed at developing and experimenting supporting tools for fault injection into VHDL models. The chapter first identifies the possible means to inject faults into a VHDL model. Then, we describe two prototype tools that were developed using each of the main injection strategies previously identified. Finally, some general insights and perspectives are briefly discussed.
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| 8. |
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| 9. |
- Barbosa, Raul, et al.
(författare)
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The VALU3S ECSEL Project: Verification and Validation of Automated Systems Safety and Security
- 2020
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Ingår i: 23rd Euromicro Conference on Digital System Design (DSD).
-
Konferensbidrag (refereegranskat)abstract
- Manufacturers of automated systems and their components have been allocating an enormous amount of time and effort in R&D activities. This effort translates into an overhead on the V&V (verification and validation) process making it timeconsuming and costly. In this paper, we present an ECSEL JU project (VALU3S) that aims to evaluate the state-of-the-art V&V methods and tools, and design a multi-domain framework to create a clear structure around the components and elements needed to conduct the V&V process. The main expected benefit of the framework is to reduce time and cost needed to verify and validate automated systems with respect to safety, cyber-security, and privacy requirements. This is done through identification and classification of evaluation methods, tools, environments and concepts for V&V of automated systems with respect to the mentioned requirements. To this end, VALU3S brings together a consortium with partners from 10 different countries, amounting to a mix of 25 industrial partners, 6 leading research institutes, and 10 universities to reach the project goal.
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| 10. |
- Enblad, Malin, et al.
(författare)
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Signet Ring Cell Colorectal and Appendiceal Cancer : A Small Signet Ring Cell Component Is Also Associated with Poor Outcome
- 2023
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Ingår i: Cancers. - : MDPI. - 2072-6694. ; 15:9
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Tidskriftsartikel (refereegranskat)abstract
- Background: Colorectal signet ring cell (SRC) carcinoma with ≥50% SRCs (SRC ≥ 50) has a poor prognosis, but the prognostic role of SRCs < 50% (SRC < 50) is unclear. The aim of this study was to provide a clinicopathological characterization of SRC colorectal and appendiceal tumours and analyse the importance of the SRC component size.Methods: All patients in the Swedish Colorectal Cancer Registry diagnosed with colorectal or appendiceal cancer in 2009–2020 at Uppsala University Hospital, Sweden, were included. The SRCs were verified, and the components estimated by a gastrointestinal pathologist.Results: Of the 2229 colorectal cancers, 51 (2.3%) had SRCs, with a median component size of 30% (interquartile range of 12.5–40) and 10 (0.45%) had SRC ≥ 50. The SRC tumours were primarily localized in the right colon (59%) and appendix (16%). No patients with SRCs had stage I disease, and 26 (51%) had stage IV, of whom, 18 (69%) had peritoneal metastases. The SRC tumours were often high grade with perineural and vascular invasion. The 5-year overall survival (OS) rate for patients with SRC ≥ 50 were 20% (95% confidence interval (CI) 6–70), for SRC < 50, 39% (95% CI 24–61); and for non-SRCs, 55% (95% CI 55–60). Among the patients with SRC < 50 and <50% extracellular mucin, the 5-year OS was 34% (95% CI 19–61), while those with ≥50% extracellular mucin had an OS of 50% (95% CI 25–99). The 5-year recurrence-free survival rates were 51% (95% CI 13–83) for patients with SRC tumours, as compared to 83% (95% CI 77–89) and 81% (95% CI 79–84) for mucinous and non-mucinous adenocarcinoma, respectively.Conclusions: The presence of SRCs was strongly associated with aggressive clinicopathological features, peritoneal metastases, and poor prognosis, also when they make up <50% of a tumour.Simple SummarySignet ring cell (SRC) carcinoma of colorectal and appendiceal cancer is rare but is recognized as the histopathological subtype with the poorest prognosis. However, the prognostic relevance of a SRC component <50% is unclear. The aim of this study was to provide a clinicopathological characterization of all SRC-containing colorectal and appendiceal cancers, including those with <50% SRCs. The results showed that SRCs, both ≥50% and <50%, were associated with aggressive histopathological features, advanced stages, and, particularly, peritoneal metastases. Information about the presence of SRCs in tumour tissue, not only in the case of ≥50% SRCs, should be routinely registered in pathology reports and clinical registers to enable larger studies that can aid our understanding of SRCs in colorectal and appendiceal cancers.
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| 11. |
- Ferrari, Enrico, et al.
(författare)
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Criteria for the Analysis of Gaps and Limitations of V&V Methods for Safety- and Security-Critical Systems
- 2022
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Konferensbidrag (refereegranskat)abstract
- As society increasingly relies on safety- and security- critical systems, the need for confirming their dependability becomes essential. Adequate V&V (verification and validation) methods must be employed, e.g., for system testing. When selecting and using the methods, it is important to analyze their possible gaps and limitations, such as scalability issues. However, and as we have experienced, common, explicitly defined criteria are seldom used for such analyses. This results in analyses that consider different aspects and to a different extent, hindering their comparison and thus the comparison of the V&V methods. As a solution, we present a set of criteria for the analysis of gaps and limitations of V&V methods for safety- and security-critical systems. The criteria have been identified in the scope of the VALU3S project. Sixty-two people from 33 organizations agreed upon the use of nine criteria: functionality, accuracy, scalability, deployment, learning curve, automation, reference environment, cost, and standards. Their use led to more homogeneous and more detailed analyses when compared to similar previous efforts. We argue that the proposed criteria can be helpful to others when having to deal with similar activities.
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| 12. |
- Folkesson, Anders, 1976-
(författare)
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Towards sustainable urban transportation : Test, demonstration and development of fuel cell and hybrid-electric buses
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Several aspects make today’s transport system non-sustainable: • Production, transport and combustion of fossil fuels lead to global and local environmental problems. • Oil dependency in the transport sector may lead to economical and political instability. • Air pollution, noise, congestion and land-use may jeopardise public health and quality of life, especially in urban areas. In a sustainable urban transport system most trips are made with public transport because high convenience and comfort makes travelling with public transport attractive. In terms of emissions, including noise, the vehicles are environmentally sustainable, locally as well as globally. Vehicles are energy-efficient and the primary energy stems from renewable sources. Costs are reasonable for all involved, from passengers, bus operators and transport authorities to vehicle manufacturers. The system is thus commercially viable on its own merits. This thesis presents the results from three projects involving different concept buses, all with different powertrains. The first two projects included technical evaluations, including tests, of two different fuel cell buses. The third project focussed on development of a series hybrid-bus with internal combustion engine intended for production around 2010. The research on the fuel cell buses included evaluations of the energy efficiency improvement potential using energy mapping and vehicle simulations. Attitudes to hydrogen fuel cell buses among passengers, bus drivers and bus operators were investigated. Safety aspects of hydrogen as a vehicle fuel were analysed and the use of hydrogen compared to electrical energy storage were also investigated. One main conclusion is that a city bus should be considered as one energy system, because auxiliaries contribute largely to the energy use. Focussing only on the powertrain is not sufficient. The importance of mitigating losses far down an energy conversion chain is emphasised. The Scania hybrid fuel cell bus showed the long-term potential of fuel cells, advanced auxiliaries and hybrid-electric powertrains, but technologies applied in that bus are not yet viable in terms of cost or robustness over the service life of a bus. Results from the EU-project CUTE show that hydrogen fuelled fuel cell buses are viable for real-life operation. Successful operation and public acceptance show that focus on robustness and cost in vehicle design were key success factors, despite the resulting poor fuel economy. Hybrid-electric powertrains are feasible in stop-and-go city operation. Fuel consumption can be reduced, comfort improved, noise lowered and the main power source downsized and operated less dynamically. The potential for design improvements due to flexible component packaging is implemented in the Scania hybrid concept bus. This bus and the framework for its hybrid management system are discussed in this thesis. The development of buses for a more sustainable urban transport should be made in small steps to secure technical and economical realism, which both are needed to guarantee commercialisation and volume of production. This is needed for alternative products to have a significant influence. Hybrid buses with internal combustion engines running on renewable fuel is tomorrow’s technology, which paves the way for plug-in hybrid, battery electric and fuel cell hybrid vehicles the day after tomorrow.
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| 13. |
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| 14. |
- Folkesson, Peter, 1968
(författare)
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Assessment and Comparison of Physical Fault Injection Techniques
- 1999
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis deals with the problem of validating and estimating the effectiveness of error handling mechanisms in computer systems. The main contribution is an assessment of the effectiveness and usefulness of several physical fault injection techniques. The assessment is based on fault injection experiments conducted on the fault-tolerant, distributed, real-time system MARS and the Thor microprocessor. Another key contribution is the validation of the error handling mechanisms included in these systems. The MARS system was evaluated using heavy-ion radiation, electromagnetic interference and pin level fault injection to allow, for the first time, a direct comparison of physical fault injection techniques. Significant differences in the results obtained by the techniques were observed. The results also showed that hardware based error detection mechanisms are the most effective mechanisms of MARS, but that application level mechanisms can significantly improve the error detection coverage. The thesis introduces scan-chain implemented fault injection (SCIFI), which provides higher observability and controllability than most other physical fault injection techniques. The SCIFI technique injects faults via the test access port of integrated circuits. Results of SCIFI experiments on the Thor microprocessor are compared with results of simulation based fault injection performed using a highly detailed VHDL model of Thor. The comparison show that the SCIFI technique can be more than 100 times faster than simulation based fault injection, and yet produce similar results. Additional SCIFI experiments on Thor show that the estimated error coverage may vary by more than five percentage units for different workload input sequences. A methodology for predicting the error coverage for various input sequences based on fault injection experiments with a specific input sequence is presented. Although the accuracy of the predicted values is limited, the methodology is able to find input sequences with high, medium or low error coverage.
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| 15. |
- Folkesson, Peter, 1968, et al.
(författare)
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Back-to-Back Fault Injection Testing in Model-Based Development
- 2015
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Ingår i: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics). - Cham : Springer International Publishing. - 1611-3349 .- 0302-9743. - 9783319242545 - 9783319242552 ; 9337, s. 135-148
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Konferensbidrag (refereegranskat)abstract
- Today, embedded systems across industrial domains (e.g., avionics, automotive) are representatives of software-intensive systems with increasing reliance on software and growing complexity. It has become critically important to verify software in a time, resource and cost effective manner. Furthermore, industrial domains are striving to comply with the requirements of relevant safety standards. This paper proposes a novel workflow along with tool support to evaluate robustness of software in model-based development environment, assuming different abstraction levels of representing software. We then show the effectiveness of our technique, on a brake-by-wire application, by performing back-to-back fault injection testing between two different abstraction levels using MODIFI for the Simulink model and GOOFI-2 for the generated code running on the target microcontroller. Our proposed method and tool support facilitates not only verifying software during early phases of the development lifecycle but also fulfilling back-to-back testing requirements of ISO 26262 when using model-based development.
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| 16. |
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| 17. |
- Kleberger, Pierre, et al.
(författare)
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An Integrated Safety and Cybersecurity Resilience Framework for the Automotive Domain
- 2022
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- As vehicles become more and more connected with their surroundings and utilize an increasing number of services, they also become more exposed to threats as the attack surface increases. With increasing attack surfaces and continuing challenges of eliminating vulnerabilities, vehicles need to be designed to work even under malicious activities, i.e., under attacks. In this paper, we present a resilience framework that integrates analysis of safety and cybersecurity mechanisms. We also integrate resilience for safety and cybersecurity into the fault – error – failure chain. The framework is useful for analyzing the propagation of faults and attacks between different system layers. This facilitates identification of adequate resilience mechanisms at different system layers as well as deriving suitable test cases for verification and validation of system resilience using fault and attack injection.
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| 18. |
- Kurbasic, Emila, et al.
(författare)
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Changes in glycoprotein expression between primary breast tumour and synchronous lymph node metastases or asynchronous distant metastases.
- 2015
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Ingår i: Clinical Proteomics. - : Springer Science and Business Media LLC. - 1559-0275 .- 1542-6416. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- Breast cancer is a very heterogeneous disease and some patients are cured by the surgical removal of the primary tumour whilst other patients suffer from metastasis and spreading of the disease, despite adjuvant therapy. A number of prognostic and treatment predictive factors have been identified such as tumour size, oestrogen (ER) and progesterone (PgR) receptor status, human epidermal growth factor receptor type 2 (HER2) status, histological grade, Ki67 and age. Lymph node involvement is also assessed during surgery to determine if the tumour has spread which requires dissection of the axilla and adjuvant treatment. The prognostic and treatment predictive factors assessing the nature of the tumour are all routinely based on the status of the primary tumour.
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| 19. |
- Lijun, Shan, et al.
(författare)
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A Survey on the Application of Safety, Security,and Privacy Standards for Dependable Systems
- 2019
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Ingår i: Proceedings of the 15th European Dependable Computing Conference.
-
Konferensbidrag (refereegranskat)abstract
- Safety-critical systems are required to comply withsafety standards as well as security and privacy standards.In order to provide insights into how practitioners apply thestandards on safety, security or privacy (Sa/Se/Pr), as well ashow they employ Sa/Se/Pr analysis methodologies and softwaretools to meet such criteria, we conducted a questionnaire-basedsurvey. This paper summarizes our major analysis results of thereceived responses.
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| 20. |
- Maleki, Mehdi, et al.
(författare)
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Modeling and Evaluating the Effects of Jamming Attacks on Connected Automated Road Vehicles
- 2022
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Ingår i: Proceedings of IEEE Pacific Rim International Symposium on Dependable Computing, PRDC. - 1541-0110. ; 2022-November, s. 12-23
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Konferensbidrag (refereegranskat)abstract
- In this work, we evaluate the safety of a platoon of four vehicles under jamming attacks. The platooning application is provided by Plexe-veins, which is a cooperative driving framework, and the vehicles in the platoon are equipped with cooperative adaptive cruise control controllers to represent the vehicles' behavior. The jamming attacks investigated are modeled by extending ComFASE (a Communication Fault and Attack Simulation Engine) and represent three real-world attacks, namely, destructive interference, barrage jamming, and deceptive jamming. The attacks are injected in the physical layer of the IEEE 802.11p communication protocol simulated in Veins (a vehicular network simulator). To evaluate the safety implications of the injected attacks, the experimental results are classified by using the deceleration profiles and collision incidents of the vehicles. The results of our experiments show that jamming attacks on the communication can jeopardize vehicle safety, causing emergency braking and collision incidents. Moreover, we describe the impact of different attack injection parameters (such as, attack start time, attack duration and attack value) on the behavior of the vehicles subjected to the attacks.
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| 21. |
- Malik, Mateen, et al.
(författare)
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ComFASE: A Tool for Evaluating the Effects of V2V Communication Faults and Attacks on Automated Vehicles
- 2022
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Ingår i: Proceedings - 52nd Annual IEEE/IFIP International Conference on Dependable Systems and Networks, DSN 2022. ; , s. 185-192
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Konferensbidrag (refereegranskat)abstract
- This paper presents ComFASE, a communication fault and attack simulation engine. ComFASE is used to identify and evaluate potentially dangerous behaviours of interconnected automated vehicles in the presence of faults and attacks in wireless vehicular networks. ComFASE is built on top of OM-NET++ (a network simulator) and integrates SUMO (a traffic simulator) and Veins (a vehicular network simulator). The tool is flexible in modelling different types of faults and attacks and can be effectively used to study the interplay between safety and cybersecurity attributes by injecting cybersecurity attacks and evaluating their safety implications. To demonstrate the tool, we present results from a series of simulation experiments, where we injected delay and denial-of-service attacks on wireless messages exchanged between vehicles in a platooning application. The results show how different variants of attacks influence the platooning system in terms of collision incidents.
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| 22. |
- Malik, Mateen, et al.
(författare)
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Simulation-based Evaluation of a Remotely Operated Road Vehicle under Transmission Delays and Denial-of-Service Attacks
- 2023
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Ingår i: Proceedings of IEEE Pacific Rim International Symposium on Dependable Computing, PRDC. - : IEEE Computer Society. - 1541-0110. ; 2023, s. 23-29
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Konferensbidrag (refereegranskat)abstract
- A remotely operated road vehicle (RORV) refers to a vehicle operated wirelessly from a remote location. In this paper, we report results from an evaluation of two safety mechanisms: safe braking and disconnection. These safety mechanisms are included in the control software for RORV developed by Roboauto, an intelligent mobility solutions provider. The safety mechanisms monitor the communication system to detect packet transmission delays, lost messages, and outages caused by naturally occurring interference as well as denial-of-service (DoS) attacks. When the delay in the communication channel exceeds certain threshold values, the safety mechanisms are to initiate control actions to reduce the vehicle speed or stop the affected vehicle safely as soon as possible. To evaluate the effectiveness of the safety mechanisms, we exposed the vehicle control software to various communication failures using a software-in-the-loop (SIL) testing environment developed specifically for this study. Our results show that the safety mechanisms behaved correctly for a vast majority of the simulated communication failures. However, in a few cases, we noted that the safety mechanisms were triggered incorrectly, either too early or too late, according to the system specification.
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| 23. |
- Mohamad, Mazen, et al.
(författare)
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Cybersecurity Pathways Towards CE-Certified Autonomous Forestry Machines
- 2024
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Ingår i: arXiv.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- he increased importance of cybersecurity in autonomous machinery is becoming evident in the forestry domain. Forestry worksites are becoming more complex with the involvement of multiple systems and system of systems. Hence, there is a need to investigate how to address cybersecurity challenges for autonomous systems of systems in the forestry domain. Using a literature review and adapting standards from similar domains, as well as collaborative sessions with domain experts, we identify challenges towards CE-certified autonomous forestry machines focusing on cybersecurity and safety. Furthermore, we discuss the relationship between safety and cybersecurity risk assessment and their relation to AI, highlighting the need for a holistic methodology for their assurance.
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| 24. |
- Roca Rubio, Maria Fernanda, 1989-, et al.
(författare)
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Associations between various markers of intestinal barrier and immune function after a high-intensity exercise challenge
- 2024
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Ingår i: Physiological Reports. - : John Wiley & Sons. - 2051-817X. ; 12:10
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Tidskriftsartikel (refereegranskat)abstract
- Strenuous exercise can result in disruption of intestinal barrier function and occurrence of gastrointestinal symptoms. The aim of this exploratory study was to elucidate systemic effects of increased intestinal permeability after high-intensity exercise. Forty-one endurance-trained subjects performed a 60-min treadmill run at 80% VO2max. Small intestinal permeability was measured as urinary excretion ratio of lactulose/rhamnose (L/R). Blood, saliva and feces were analyzed for gut barrier and immune-related biomarkers. The exercise challenge increased several markers of intestinal barrier disruption, immune function and oxidative stress. We found a negative correlation between L/R ratio and uric acid (r = -0.480), as well as a positive correlation between the L/R ratio and fecal chromogranin A in male participants (r = 0.555). No significant correlations were found between any of the markers and gastrointestinal symptoms, however, perceived exertion correlated with the combination of IL-6, IL-10 and salivary cortisol (r = 0.492). The lack of correlation between intestinal permeability and gastrointestinal symptoms could be due to minor symptoms experienced in lab settings compared to real-life competitions. The correlation between L/R ratio and uric acid might imply a barrier-protective effect of uric acid, and inflammatory processes due to strenuous exercise seem to play an important role regarding physical exhaustion.
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| 25. |
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