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(searched for: (title:(Free Kick but that was not the Goal)
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Shabih Manzar
Journal of Biomedical Research & Environmental Sciences, Volume 6, pp 173-174; doi:10.37871/jbres1139

Abstract:
Misadventure of the chest tube has been described in the literature resulting in complications [1-5].
Theofilos Ch. Valkanidis , Cathy M. Craig, Alan Cummins, Joost C. Dessing
Published: 18 December 2019
Abstract:
Free kicks are an important goal scoring opportunity in football. It is an unwritten rule that the goalkeeper places a wall of defending players with the aim of making scoring harder for the attacking team. However, the defensive wall can occlude the movements of the kicker, as well as the initial part of the ball trajectory. Research on one-handed catching suggests that a ball coming into view later will likely delay movement initiation and possibly affect performance. Here, we used virtual reality to investigate the effect of the visual occlusion of the initial ball trajectory by the wall on the performance of naïve participants and skilled goalkeepers. We showed that movements were initiated significantly later when the wall was present, but not by the same amount as the duration of occlusion (~200ms, versus a movement delay of ~70-90ms); movements were thus initiated sooner after the ball came into view, based on less accumulated information. For both naïve participants and skilled goalkeepers this delayed initiation significantly affected performance (i.e., 3.6cm and 1.5cm larger spatial hand error, respectively, not differing significantly between the groups). These performance reductions were significantly larger for shorter flight times, reaching increased spatial errors of 4.5cm and 2.8cm for both groups, respectively. Further analyses showed that the wall-induced performance reduction did not differ significantly between free kicks with and without sideward curve. The wall induced early movement biases, but only for free kicks with curve in the same direction as the required movement; these biases were away from the final ball position, thus hampering performance. Our results cannot suggest an all-out removal of the wall - this study only considered one potential downside – but should motivate goalkeepers to continuously evaluate whether placing a wall is their best option. This seems most pertinent when facing expert free kick takers for whom the wall does not act as a block (i.e., whose kicks consistently scale the wall).
Published: 31 December 2020
PLoS ONE, Volume 15; doi:10.1371/journal.pone.0243287

Abstract:
Free kicks are an important goal scoring opportunity in football. It is an unwritten rule that the goalkeeper places a wall of defending players with the aim of making scoring harder for the attacking team. However, the defensive wall can occlude the movements of the kicker, as well as the initial part of the ball trajectory. Research on one-handed catching suggests that a ball coming into view later will likely delay movement initiation and possibly affect performance. Here, we used virtual reality to investigate the effect of the visual occlusion of the initial ball trajectory by the wall on the performance of naïve participants and skilled goalkeepers. We showed that movements were initiated significantly later when the wall was present, but not by the same amount as the duration of occlusion (~200ms, versus a movement delay of ~70-90ms); movements were thus initiated sooner after the ball came into view, based on less accumulated information. For both naïve participants and skilled goalkeepers this delayed initiation significantly affected performance (i.e., 3.6cm and 1.5cm larger spatial hand error, respectively, not differing significantly between the groups). These performance reductions were significantly larger for shorter flight times, reaching increased spatial errors of 4.5cm and 2.8cm for both groups, respectively. Further analyses showed that the wall-induced performance reduction did not differ significantly between free kicks with and without sideward curve. The wall influenced early movement biases, but only for free kicks with curve in the same direction as the required movement; these biases were away from the final ball position, thus hampering performance. Our results cannot suggest an all-out removal of the wall–this study only considered one potential downside–but should motivate goalkeepers to continuously evaluate whether placing a wall is their best option. This seems most pertinent when facing expert free kick takers for whom the wall does not act as a block (i.e., whose kicks consistently scale the wall).
Bauke M. De Jong
Published: 21 February 2019
Frontiers in Psychology, Volume 10; doi:10.3389/fpsyg.2019.00388

Abstract:
Self-intended action implies an initial stage of assigning an external entity as target of action, with subsequent recruitment of body-scheme information serving the free selection of an appropriate effector system to achieve the action aim. This plurality underscores the concept that neuronal response freedom underlying the generation of such action is not necessarily restricted to a singular cerebral event at its initiation, but that such freedom is embedded in a series of successive processing steps. In this respect, action intention initially concerns the transition of a neutral object into a target of action, while the “will” to act further crystalizes with the recruitment of one’s body scheme. The latter is a prerequisite for effector selection and indeed complements the emerging sense of agency. This temporal order of neuronal events fits a model of fronto-parietal interactions associated with volition. A concise behavioral experiment is additionally described, in which successively displayed balls represent either a recognizable object with distinct shape and color features, or a target of action. Instructions to write down the ball’s characteristics were alternated by the command ”action.” When shifting from a neutral object to an action target, the ball was placed in one of three backgrounds: empty, an outdoor goal or indoor basket. In response to the action command, subjects reported intended actions such as kicking, seizing, throwing and heading, thus implicitly referring to the foot, hand, or head as chosen effector. For the latter the parietal cortex is strongly implicated, not only concerning predefined but also free selection. Although subjects were free to choose what to do with the ball, the environmental cues of the ball strongly influenced their choices. These results illustrate the temporal order in fronto-parietal processing associated with initial target assignment, instantly followed by the embodiment of will, i.e., the recruitment of body-scheme information for possible effector selection. Such multistage neuronal processing underlying free action selection underscores that the onset of brain signals prior to the perceived sense of free will is not a valid argument to reduce free will to an illusion.
Jörg Rossbach, Jochen R. Schneider, Wilfried Wurth
Published: 1 May 2019
Physics Reports, Volume 808, pp 1-74; doi:10.1016/j.physrep.2019.02.002

Abstract:
Free-electron lasers produce extremely brief, coherent, and bright laser-like photon pulses that allow to image matter at atomic resolution and at timescales faster than the characteristic atomic motions. In pulses of about 50 femtoseconds duration they provide as many photons as one gets in 1 s from modern storage ring synchrotron radiation facilities. FLASH, the Free-Electron Laser at DESY in Hamburg was the first FEL in the XUV/soft X-ray spectral range, started operation as a user facility in summer 2005, and was for almost 5 years the only short wavelength FEL facility worldwide. Hence, most of the technological developments as well as the scientific experiments performed by the user community were new and unique as outlined below. FLASH was driving FEL science and technology and paved the way for many new ideas. Because of using a linear accelerator in superconducting RF technology FLASH combines the extreme peak brightness characteristic for FELs with very high average brightness. It also was the prototype for the European XFEL located in the Hamburg metropolitan area, which started user operation in summer 2017. The present review provides an overview of the progress made with accelerator science and technology at FLASH for the production of stable beams of well characterized electron pulses, reduction of the pulse jitter to the femtosecond level, generation of ultra-short photon pulses, adequate synchronization of the machine parameters with the experiment, and demonstrating advanced FEL schemes using variable gap undulators. Much of this was done in the very exciting early days of FEL science when it was even not clear if the FEL concept could be realized for X-rays. The development and the operation of the FLASH user facility is described, as well as the techniques developed to make use of the new type of X-ray beams including photon beam diagnostics and damage studies of the optical elements. The review emphasizes breakthrough experiments which demonstrated that many of the ideas collected in the world-wide discussion of the scientific case of free-electron lasers could indeed be realized and they often produced unexpected results. The first experiment on Coulomb explosion of Xe clusters performed in 2002 was a clear demonstration of the feasibility of experiments with free-electron laser beams and opened a lively discussion in the atom, molecular and optical physics community (AMO). Time resolved single-shot single-particle imaging, summarized in the slogan “Take movies instead of pictures”, was one of the most popular science drivers for the construction of free-electron X-ray lasers. As a first step in this direction experiments using a highly focused beam of FLASH demonstrated that pictures of 2 dimensional objects could be reconstructed from single-shot single-particle diffraction patterns. Explosion dynamics of nano-size particles hit by an intense FEL pulse were studied. This method, called “diffraction before destruction”, is now very successfully applied with hard X-rays and, to a large extend, solves the radiation damage problem in structural biology. A long term goal is to determine the 3 dimensional structure of a large molecule from a single-shot diffraction pattern. Along these lines the 3D architecture of free Ag nanoparticles could be determined from one diffraction pattern only using soft X-rays from FLASH. To understand light-matter interactions in this new parameter space a number of pioneering AMO experiments have been performed including non-linear interactions in atoms, molecules and clusters. Multiphoton photoionization processes in the presence of intense optical fields have been studied, as well as photo-absorption of XUV photon energies on molecular ions important for astrophysics. The nature of formation and breaking of molecular bonds was investigated in VUV pump-VUV probe experiments using a reaction microscope and a specific delay line. As an example the process of ultrafast isomerization of acetylene molecules C2H2 triggered by single photon excitation has been studied. The structural changes during the isomerization process were visualized and an isomerization time of 52 +/- 15 fs was found. Clusters of variable size, which can be produced routinely, allow distinguish between inter- and intra-atomic effects and are considered model systems for the investigation of light-matter interactions in multi-atom objects. As an example such experimental studies provided instructive data for benchmarking theoretical models describing cluster ionization in intense short-wavelength laser pulses. The combination of single-shot single-particle imaging for determination of the cluster size with spectroscopy was crucial for success of these experiments. The investigations could later be extended to very large Xe clusters providing new insights into the nanoplasma formation and explosion dynamics of such large systems From early on, studies of high energy density plasmas and warm dense matter have been one of the most prominent research fields in building the scientific case for X-ray free-electron lasers. A good understanding of this complex regime between cold solids and hot dilute plasmas is important for high pressure studies, applied materials studies, inertial fusion, and planetary interiors. With the first observation of saturable absorption of an L-shell transition in Aluminum and pioneering studies of warm dense hydrogen FLASH kicked off research of matter in extreme conditions with free-electron lasers. In condensed matter experiments the emphasis is not so much on the peak power of the FEL beam and extreme focusing, but on beam properties like polarization and pulse duration. The sample has to stay intact in the beam over hours and the number of photons per pulse impinging on the sample has to be limited to avoid space charge effects. After demonstrating the possibility to record single-shot resonant magnetic scattering...
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