Memory with memory in genetic programming

We introduce Memory with Memory Genetic Programming (MwM-GP), where we use soft assignments and soft return operations. Instead of having the new value completely overwrite the old value of registers or memory, soft assignments combine such values. Similarly, in soft return operations the value of a function node is a blend between the result of a calculation and previously returned results. In extensive empirical tests, MwM-GP almost always does as well as traditional GP, while significantly outperforming it in several cases. MwM-GP also tends to be far more consistent than traditional GP. The data suggest that MwM-GP works by successively refining an approximate solution to the target problem and that it is much less likely to have truly ineffective code. MwM-GP can continue to improve over time, but it is less likely to get the sort of exact solution that one might find with traditional GP

A Clinical Trial to Validate Event-Related Potential Markers of Alzheimer\u27s Disease in Outpatient Settings

INTRODUCTION: We investigated whether event-related potentials (ERP) collected in outpatient settings and analyzed with standardized methods can provide a sensitive and reliable measure of the cognitive deficits associated with early Alzheimer\u27s disease (AD). METHODS: A total of 103 subjects with probable mild AD and 101 healthy controls were recruited at seven clinical study sites. Subjects were tested using an auditory oddball ERP paradigm. RESULTS: Subjects with mild AD showed lower amplitude and increased latency for ERP features associated with attention, working memory, and executive function. These subjects also had decreased accuracy and longer reaction time in the target detection task associated with the ERP test. DISCUSSION: Analysis of ERP data showed significant changes in subjects with mild AD that are consistent with the cognitive deficits found in this population. The use of an integrated hardware/software system for data acquisition and automated data analysis methods make administration of ERP tests practical in outpatient settings

Low-mass pre--main-sequence stars in the Magellanic Clouds

[Abridged] The stellar Initial Mass Function (IMF) suggests that sub-solar stars form in very large numbers. Most attractive places for catching low-mass star formation in the act are young stellar clusters and associations, still (half-)embedded in star-forming regions. The low-mass stars in such regions are still in their pre--main-sequence (PMS) evolutionary phase. The peculiar nature of these objects and the contamination of their samples by the evolved populations of the Galactic disk impose demanding observational techniques for the detection of complete numbers of PMS stars in the Milky Way. The Magellanic Clouds, the companion galaxies to our own, demonstrate an exceptional star formation activity. The low extinction and stellar field contamination in star-forming regions of these galaxies imply a more efficient detection of low-mass PMS stars than in the Milky Way, but their distance from us make the application of special detection techniques unfeasible. Nonetheless, imaging with the Hubble Space Telescope yield the discovery of solar and sub-solar PMS stars in the Magellanic Clouds from photometry alone. Unprecedented numbers of such objects are identified as the low-mass stellar content of their star-forming regions, changing completely our picture of young stellar systems outside the Milky Way, and extending the extragalactic stellar IMF below the persisting threshold of a few solar masses. This review presents the recent developments in the investigation of PMS stars in the Magellanic Clouds, with special focus on the limitations by single-epoch photometry that can only be circumvented by the detailed study of the observable behavior of these stars in the color-magnitude diagram. The achieved characterization of the low-mass PMS stars in the Magellanic Clouds allowed thus a more comprehensive understanding of the star formation process in our neighboring galaxies.Comment: Review paper, 26 pages (in LaTeX style for Springer journals), 4 figures. Accepted for publication in Space Science Review

Biased competition through variations in amplitude of γ-oscillations

Experiments in visual cortex have shown that the firing rate of a neuron in response to the simultaneous presentation of a preferred and non-preferred stimulus within the receptive field is intermediate between that for the two stimuli alone (stimulus competition). Attention directed to one of the stimuli drives the response towards the response induced by the attended stimulus alone (selective attention). This study shows that a simple feedforward model with fixed synaptic conductance values can reproduce these two phenomena using synchronization in the gamma-frequency range to increase the effective synaptic gain for the responses to the attended stimulus. The performance of the model is robust to changes in the parameter values. The model predicts that the phase locking between presynaptic input and output spikes increases with attention

Negative slow waves as indices of anticipation: The Bereitschaftspotential, the Contingent Negative Variation, and the Stimulus-Preceding Negativity

Koordinacija je bitan preduvjet uspješnog nogometaša te se već u najranijoj dobi trening treba usmjeriti upravo na razvoj koordinacije, kao i motoričko učenje i agilnost. Iz tog je razloga potrebno provoditi istraživanja koja bi dovela do novih saznanja o utjecaju treninga koordinacije i time poslužila nogometnim trenerima u planiranju treninga djece i mladih. U ovom istraživanju uzorak ispitanika sastavljen je od 20 dječaka U13 kategorije, članova Nogometnog kluba Zagreb, s kojima se nakon inicijalnog testiranja provodio četverotjedni bazični i specifični program treninga. Ispitanici su nakon inicijalnog testiranja nasumično podijeljeni u 2 grupe. U prvoj grupi provodio se bazični koordinacijski trening, a u drugoj specifični koordinacijski trening te su zajedno odrađivali nogometni trening. Tijekom četverotjednog ciklusa treninga, kod prve grupe djece provodio se bazični trening koordinacije cijelog tijela sa i bez lopte, dok su kod druge grupe provedeni specifični koordinacijski sadržaji nogometnog karaktera. Tijekom tog perioda provedena su 3 treninga tjedno u trajanju od 45 minuta. Nakon četverotjednog programa treninga provedeno je završno testiranje s ciljem analize učinka koordinacijskog treninga. Dva testa korištena su prilikom testiranja djece sportaša, a usmjereni su na mjerenje preciznosti, brzine i specifične koordinacije.(maknut agilnost iz prijevoda) Prvi test bio je „Loughborough test dodavanja za mlade sportaše“ a koristi se za procjenu preciznosti, brzine i specifične koordinacije. Drugi test bio je „Zig-zag test vođenja lopte s promjenom smjera“ za procjenu specifičnih koordinacijskih sposobnosti (brza promjena smjera kretanja). Obje grupe ostvarile su statistički značajan napredak u specifičnim koordinacijskim sposobnostima, ali ne postoje razlike između grupa koje bi se mogle pripisati karakteristikama pojedinog programa treninga. Eksperimentalna grupa koja je provodila specifični koordinacijski program u finalnom testiranju imala je bolje rezultate, ali numerički oni nisu statistički značajni u odnosu na kontrolnu grupu koja je provodila bazični koordinacijski program. Cilj ovog istraživanja je utvrditi učinke koordinacijskog treninga na specifičnu tehničku izvedbu (vođenje i dodavanje lopte), specifične koordinacijske sposobnosti između djece nogometaša, nakon provedenog četverotjednog ciklusa bazičnog i specifičnog treninga koordinacije.Coordination is an important prerequisite for a successful football player, and from an early age, training should focus on the development of coordination, as well as motor learning and agility. This is the reason why it is necessary to conduct research that would lead to new knowledge about the impact of coordination training and thus serve football coaches in planning the training for children and youth. In this research, the sample of examinees consisted of 20 boys of the U13 category, members of Zagreb Football Club with whom, after the initial testing, a four-week basic and specific training program was conducted. After the initial testing, the subjects were divided into 2 groups, in a randomized way. In the first group, basic coordination training was conducted, while in the second group, specific coordination training was conducted, and together they did football training. During the four-week training cycle, the first group of children conducted basic full body coordination training with and without the ball, while the second group conducted specific coordination content of a football nature. During this period, 3 workouts per week lasting 45 minutes were performed. After a four-week training program, a final test was conducted to analyze the impact of coordination training. Two tests were used during the testing of children athletes, and were focused on measuring accuracy, speed and specific coordination. The first test was the "Loughborough Pass Test for Young Athletes" and is used to assess accuracy, speed and specific coordination. The second test was the "Zig-zag directional ball test" to assess specific coordination abilities (rapid change of direction). Both groups made statistically significant progress in specific coordination abilities, but there are no differences between the groups that could be attributed to the characteristics of each training program. The experimental group that implemented the specific coordination program in the final testing had better results, but numerically they are not statistically significant compared to the control group that implemented the basic coordination program. The aim of this research is to determine the effects of coordination training on the specific technical performance (guiding and passing the ball), specific coordination skills between children football players, after a four-week cycle of basic and specific coordination training