Search results for "Head"
showing 10 items of 1640 documents
Factors affecting peak impact force during soccer headers and implications for the mitigation of head injuries
2020
It has been documented that up to 22% of all soccer injuries are concussions. This is in part due to players purposely using their head to direct the ball during play. To provide a more complete understanding of head trauma in soccer athletes, this study characterized the effects of four soccer ball characteristics (size, inflation pressure, mass, velocity) on the resulting peak impact force as it relates to the potential for incurring neurophysiological changes. A total of six hundred trials were performed on size 4 and 5 soccer balls as well as a novel lightweight soccer ball. Impact force was measured with a force plate and ball velocity was determined using motion capture. These data we…
Service discovery protocols in D2D-enabled cellular networks: Reactive versus proactive
2014
Device-to-Device (D2D) communication, which allows access services offered by nearby devices bypassing the base station, has been regarded as an essential component of the emerging 5G mobile networks. Many advantages can be provided by this direct communication paradigm such as high data rate, traffic offloading, range extension, as well as proximity services and social networking. In such a context, service discovery approaches need to be investigated. In this paper, we propose two protocols for service discovery, namely, reactive (pull) discovery and proactive (push) discovery in infrastructure-coordinated D2D networks. The protocol overhead is calculated and numerical results are provide…
Robust Transmission for Reconfigurable Intelligent Surface Aided Millimeter Wave Vehicular Communications With Statistical CSI
2022
The integration of reconfigurable intelligent surface (RIS) into millimeter wave (mmWave) vehicular communications offers the possibility to unleash the potential of future proliferating vehicular applications. However, the high-mobility-induced rapidly varying channel state information (CSI) has been making it challenging to obtain the accurate instantaneous CSI (I-CSI) and to cope with the incurable high signaling overhead. The situation may become worse when the RIS with a large number of passive reflecting elements is deployed. To overcome this challenge, we investigate in this paper a robust transmission scheme for the time-varying RIS-aided mmWave vehicular communications, in which, s…
Autonomous Operation of Stationary Battery Energy Storage Systems—Optimal Storage Design and Economic Potential
2021
Global warming requires a changeover from fossil fuel based to renewable energy sources on the electrical supply side and electrification of the demand side. Due to the transient nature of renewables and fluctuating demand, buffer capacities are necessary to compensate for supply/demand imbalances. Battery energy storage systems are promising. However, the initial costs are high. Repurposing electric vehicle batteries can reduce initial costs. Further, storage design optimization could significantly improve costs. Therefore, a battery control algorithm was developed, and a simulation study was performed to identify the optimal storage design and its economic potential. The algorithm used is…
Elusive amines and cluster headache: mutational analysis of trace amine receptor cluster on chromosome 6q23.
2004
Cluster headache (CH) is characterised by unilateral pain and ipsilateral autonomic features. To date, no molecular genetic evidence has been shown for CH. Small pedigrees and low penetrance render the identification of the CH-gene quite difficult. Nonetheless the association of CH and migraine to a new class of amine, namely trace or elusive amines such as tyramine, octopamine and synephrine, has recently been demonstrated. In particular, in comparison to healthy control subjects, all these neurotransmitters have been found to be greatly elevated in CH sufferers in plasma and platelets both in active and remission periods. A cluster of gene-encoding G-protein-coupled receptors that bind an…
Are IL-10+ regulatory Th17 cells implicated in the sustained response to glucocorticoid treatment in patients with giant cell arteritis? Comment on t…
2013
We have read with interest the recently published paper of Espigol-Frigole et al 1 in which the authors confirmed that interleukin (IL)-17 is highly expressed in giant cell arteritis (GCA) lesions.1–3 They also demonstrated for the first time that IL-17 expression in temporal artery biopsies (TABs) was correlated with a better outcome. Among other interesting results, the identification of Foxp3+IL-17+ T cells by confocal microscopy in TAB made the authors to hypothesize that these cells could be induced regulatory T cells (Treg) that may facilitate the remission of the disease under steroid therapy. …
Bioelectrical model of head-tail patterning based on cell ion channels and intercellular gap junctions
2020
Robust control of anterior-posterior axial patterning during regeneration is mediated by bioelectric signaling. However, a number of systems-level properties of bioelectrochemical circuits, including stochastic outcomes such as seen in permanently de-stabilized "cryptic" flatworms, are not completely understood. We present a bioelectrical model for head-tail patterning that combines single-cell characteristics such as membrane ion channels with multicellular community effects via voltage-gated gap junctions. It complements the biochemically-focused models by describing the effects of intercellular electrochemical coupling, cutting plane, and gap junction blocking of the multicellular ensemb…
Assessing autophagy in archived tissue or how to capture autophagic flux from a tissue snapshot
2020
This article belongs to the Special Issue Autophagy in Cancer.
Differential expression of the corticosteroid receptors GR1, GR2 and MR in rainbow trout organs with slow release cortisol implants
2012
The present study describes the transcriptional levels of the corticosteroid receptors (CRs) GR1, GR2 and MR in the different organs of the rainbow trout (Oncorhynchus mykiss) in response to a slow release of cortisol, throughout a 10-day period. We show that after short term (1 day after cortisol implantation), when the plasma levels of cortisol emulate an acute stress, the GR2 and MR expression levels were upregulated in the brain and head kidney tissues. This result reflects the role of these organs as regulators of the stress response. In general, the rest of the organs, especially gills, intestine, liver, muscle and spleen, showed decreased transcriptional levels of GR1, GR2 and MR, al…
Biodynamic behavior of the trunk and the abdomen during whole-body vibration
1989
Vibration strain may be defined as the sum of all reactions of the human being to vibration exposure. This also includes the biomechanical behavior of particular parts of the body. Knowledge about these reactions is necessary in the field of occupational health and ergonomics. Biomechanical models, experimental methods, and results are presented. It can be shown that under vibration exposure with different conditions (body posture, vibration direction), the body parts are in resonance at varying frequencies, mainly in a low frequency range.