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Fully Synthetic Longitudinal Real-World Data From Hearing Aid Wearers for Public Health Policy Modeling
Here, we share the first outcome of EVOTION (www.h2020evotion.eu) in the form of a data-set to inspire, encourage, and motivate a data-driven analytical approach to evidence-based healthcare policy modeling using real-world longitudinal data. The data-set includes information relating to patterns of real-world hearing aid usage and sound environment exposure. Undoubtedly, many such data-sources will be available for researchers and policy-makers in the future, and the data-set presented here can act as a first step of building and testing potential statistical model
Electromechanical Delay of the Knee Flexor Muscles Is Impaired After Harvesting Hamstring Tendons for Anterior Cruciate Ligament Reconstruction
Background
Changes in electromechanical delay during muscle activation are expected when there are substantial alterations in the structural properties of the musculotendinous tissue. In anterior cruciate ligament reconstruction, specific tendons are being harvested for grafts. Thus, there is an associated scar tissue development at the tendon that may affect the corresponding electromechanical delay. Purpose
This study was conducted to investigate whether harvesting of semitendinosus and gracilis tendons for anterior cruciate ligament reconstruction will affect the electromechanical delay of the knee flexors. Study Design
Case-control study; Level of evidence, 3. Methods
The authors evaluated 12 patients with anterior cruciate ligament reconstruction with a semitendinosus and gracilis autograft, 2 years after the reconstruction, and 12 healthy controls. Each participant performed 4 maximally explosive isometric contractions with a 1-minute break between contractions. The surface electromyographic activity of the biceps femoris and the semitendinosus was recorded from both legs during the contractions. Results
The statistical comparisons revealed significant increases of the electromechanical delay of the anterior cruciate ligament–reconstructed knee for both investigated muscles. Specifically, the electromechanical delay values were increased for both the biceps femoris (P = .029) and the semitendinosus (P = .005) of the reconstructed knee when compared with the intact knee. Comparing the anterior cruciate ligament–reconstructed knee against healthy controls revealed similar significant differences for both muscles (semitendinosus, P = .011; biceps femoris, P = .024). Conclusion
The results showed that harvesting the semitendinosus and gracilis tendons for anterior cruciate ligament reconstruction significantly increased the electromechanical delay of the knee flexors. Increased hamstring electromechanical delay might impair knee safety and performance by modifying the transfer time of muscle tension to the tibia and therefore affecting muscle response during sudden movements in athletic activities. However, further investigation is required to identify whether the increased electromechanical delay of the hamstrings can actually influence optimal sports performance and increase the risk for knee injury in athletes with anterior cruciate ligament reconstructions
Quantitative Analysis of Apache Storm Applications: The NewsAsset Case Study
The development of Information Systems today faces the era of Big Data. Large volumes of information need to be processed in real-time, for example, for Facebook or Twitter analysis. This paper addresses the redesign of NewsAsset, a commercial product that helps journalists by providing services, which analyzes millions of media items from the social network in real-time. Technologies like Apache Storm can help enormously in this context. We have quantitatively analyzed the new design of NewsAsset to assess whether the introduction of Apache Storm can meet the demanding performance requirements of this media product. Our assessment approach, guided by the Unified Modeling Language (UML), takes advantage, for performance analysis, of the software designs already used for development. In addition, we converted UML into a domain-specific modeling language (DSML) for Apache Storm, thus creating a profile for Storm. Later, we transformed said DSML into an appropriate language for performance evaluation, specifically, stochastic Petri nets. The assessment ended with a successful software design that certainly met the scalability requirements of NewsAsset
Electromechanical Delay of the Knee Flexor Muscles After Harvesting the Hamstrings for Anterior Cruciate Ligament Reconstruction
Objective: To investigate if harvesting of semitendinosus (ST) and gracilis for anterior cruciate ligament (ACL) reconstruction will have an effect in coordinative firing pattern of the hamstrings under fatigue. We hypothesized that fatigue will increase the electromechanical delay (EMD) of the hamstrings on the harvested site and impair the synchronization between the medial and lateral hamstrings, in terms of muscle activity onsets.
Design: Prospective nonrandomized study. Setting: Institutional. Patients: Twelve ACL reconstructed patients with hamstrings, 2 years postoperatively.
Interventions: The patients performed a fatigue protocol with 25 continuous maximal isometric voluntary contractions of 8-second duration with 2-second intervals. Main Outcome Measures: The electromyography activity of biceps femoris (BF) and ST was recorded bilaterally and simultaneously with the torque measurements. The dependent variable examined was the EMD difference between BF and ST (muscle activation pattern).
Results: The fatigue protocol caused significant differences for the EMD values for both the intact and the reconstructed leg, demonstrating the influence of fatigue in EMD. However, the synchronization pattern between the medial and lateral hamstrings did not change significantly throughout the fatiguing protocol, revealing a balanced effect of fatigue.
Conclusions: Although the EMD of ST and BF was significantly increased due to fatigue, as expected, their synchronization pattern as identified by the difference in their EMDs remained the same. Thus, the reconstructed knee responded in a balanced manner and the hamstrings firing pattern remained the same, despite the intervention to the ST tendon
Knee braces can decrease tibial rotation during pivoting that occurs in high demanding activities
Purpose
The purpose of this study was to investigate whether knee braces could effectively decrease tibial rotation during high demanding activities.
Methods
Using an in vivo three-dimensional kinematic analysis, 21 physically active, healthy, male subjects were evaluated. Each subject performed two tasks that were used extensively in the literature because they combine increased rotational and translational loads on the knee, (1) descending from a stair and subsequent pivoting and (2) landing from a platform and subsequent pivoting under three conditions: (A) wearing a prophylactic brace (braced), (B) wearing a patellofemoral brace (sleeved), and (C) unbraced condition.
Results
In the first task, tibial rotation during the pivoting phase was significantly decreased in the braced condition as compared to the sleeved condition (P = 0.019) and the non-braced condition (P = 0.002). In the second task, the same variable was significantly decreased in the braced condition as compared to the sleeved (P = 0.001) and the unbraced condition (P \u3c 0.001). The sleeved condition also produced significantly decreased tibial rotation with respect to the unbraced condition (P = 0.021).
Conclusions
Bracing decreased tibial rotation in activities where increased translational and rotational forces were applied. Because knee braces decreased tibial rotation, they can possibly be used with ACL-reconstructed and ACL-deficient patients to prevent such problems.
Level of evidence
Case–control study, Level III
How Australia’s competition regulator is supporting news, but not quality
At a time when many news media businesses are collapsing or faltering, regulators globally are wrestling with how to support news and journalism. Australia’s competition (anti-trust) regulator, the Australian Competition and Consumer Commission, or ACCC, has developed a legislative scheme known as the ‘News Media Bargaining Code’, which seeks to enforce a compulsory arbitration process to determine how much Google and Facebook must pay for the use of news content. Highly controversial and subject to extensive redrafting, this regulatory intervention was seen as necessary because of the ‘bargaining power imbalance’ between these digital platforms and local news publishers. However, in the legislation that creates the Code, the word ‘quality’ appears only once. This seems particularly problematic given that the aim of the regulatory intervention was not simply to address unequal commercial positions, but to shore up the public benefit provided by journalism. In this chapter, we explain how key concerns around digital platforms’ effect on the capacity of Australian news providers to pursue public interest journalism have been translated into policy. We argue that by deploying the tools of competition law instead of media regulation, the Australian Government is overlooking the social utility of news and is building a scheme that could incentivize the creation of poor-quality content
Search for the production of dark matter in association with top-quark pairs in the single-lepton final state in proton-proton collisions at √s=8 TeV
Peer reviewe
Search for heavy gauge W ' bosons in events with an energetic lepton and large missing transverse momentum at root s=13TeV
Peer reviewe
Measurement of top quark–antiquark pair production in association with a W or Z boson in pp collisions at √s=8 TeV
Peer reviewe
Observation of the diphoton decay of the Higgs boson and measurement of its properties
Peer reviewe
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