Power laws, memory capacity, and self-tuned critical branching in an LIF model with binary synapses

Both fluctuations and distributions of spontaneous neural spiking activity have been observed to closely follow a variety of power laws. Multiple explanations have been offered for each observation, but few lead to mechanisms that encompass their widespread occurrence. A canonical, leaky integrate-and-fire model is presented in which synapses are updated based on the timing of pre- and post-synaptic spikes in order to maintain a state of critical branching. Results showed that 1) the self-tuning algorithm maintained critical branching under a range of parameters; 2) power laws were obtained in spiking activity fluctuations (1/f scaling), size distributions of network bursts (neural avalanches), and temporal correlations in interspike intervals (Allan factor); 3) power laws disappeared once the self-tuning algorithm was disabled; and 4) critical branching was adaptive in that it maximized the network’s memory capacity when assessed as a liquid state machine

Walking across Wikipedia: a scale-free network model of semantic memory retrieval.

Semantic knowledge has been investigated using both online and offline methods. One common online method is category recall, in which members of a semantic category like "animals" are retrieved in a given period of time. The order, timing, and number of retrievals are used as assays of semantic memory processes. One common offline method is corpus analysis, in which the structure of semantic knowledge is extracted from texts using co-occurrence or encyclopedic methods. Online measures of semantic processing, as well as offline measures of semantic structure, have yielded data resembling inverse power law distributions. The aim of the present study is to investigate whether these patterns in data might be related. A semantic network model of animal knowledge is formulated on the basis of Wikipedia pages and their overlap in word probability distributions. The network is scale-free, in that node degree is related to node frequency as an inverse power law. A random walk over this network is shown to simulate a number of results from a category recall experiment, including power law-like distributions of inter-response intervals. Results are discussed in terms of theories of semantic structure and processing

The segment as the minimal planning unit in speech production and reading aloud: evidence and implications.

Speech production and reading aloud studies have much in common, especially the last stages involved in producing a response. We focus on the minimal planning unit (MPU) in articulation. Although most researchers now assume that the MPU is the syllable, we argue that it is at least as small as the segment based on negative response latencies (i.e., response initiation before presentation of the complete target) and longer initial segment durations in a reading aloud task where the initial segment is primed. We also discuss why such evidence was not found in earlier studies. Next, we rebut arguments that the segment cannot be the MPU by appealing to flexible planning scope whereby planning units of different sizes can be used due to individual differences, as well as stimulus and experimental design differences. We also discuss why negative response latencies do not arise in some situations and why anticipatory coarticulation does not preclude the segment MPU. Finally, we argue that the segment MPU is also important because it provides an alternative explanation of results implicated in the serial vs. parallel processing debate

Facial clefting and the Vietnam War: A Study of DNA Methylation Patterns and Intergenerational Stress

Changes in DNA methylation patterns have been linked to extreme stress. These patterns are heritable by the next generation. Facial clefting has been linked to changes in methylation patterns affecting craniofacial genes. In this study we explored: 1. If methylation patterns in offspring are associated with maternal exposure to extreme stress 2. If altered methylation patterns are associated with clefting in offspring 3. If the changes preferentially altered craniofacial genes. The present study used peripheral blood samples from 4 cohorts of children. Samples were randomly chosen from a larger group of 505 samples. Group 1 (N=7) have mothers born during the Vietnam war and have CL/P. Group 2 (N=8) have mothers born after the Vietnam war and have CL/P. Group 3 (N=8) have mothers born during the Vietnam war and do not have CL/P. Group 4 (N=8) have mothers born after the Vietnam war and do not have CL/P. We carried out an epigenome wide association study (EWAS) to test the association between DNA methylation pattern, exposure and cleft status, utilizing comparisons between the larger exposed and not exposed cohorts, and cross-wise comparisons between each of the smaller cohorts. Significant results were obtained at the FDR .05 level confirming that overall methylation patterns in children born to mothers who were exposed to war stress and children born to mothers who were not exposed to war stress are different. The affected genes represent an array of core biological functions from cell growth and proliferation to neurological and craniofacial development. The results for the cross-wise comparisons of groups are less conclusive, likely because of the small sample size. However, several probes were significant at the FDR .05 level. The results for the clefts vs. non-cleft groups may have identified novel loci that are associated clefting in this population. The next step in this study is to evaluate the larger group of samples to ascertain if these associations hold

Terminal for Meal Hand Out

Bakalárska práca sa zameriava na vývoj aplikácie pod operačným systémom windows 10 s použitím platformy UWP. Rieši problematiku softvérového riešenia ktoré napomáha pri výdaji jedál a zobrazení objednávok klienta.Bachelor thesis is focused on development of application for Windows 10 platform in cooperative with platform UWP. It solve information problems, which helps during meal serving, and shows client ordered meals for that day.

Pripravnost javnog zdravstva Europskih zemalja za kemijske nesreće

In response to the attack of 11 September 2001 on the USA, World Health Organization (WHO), Regional Office for Europe took immediate steps in order to be able to assist countries in case of a terrorist attack. Among other things, WHO organised a series of different consultations with international organisations, government representatives and experts in order to assess the state of preparedness at the national and international levels, to identify the main problems and to make recommendations. The problems were addressed in the context of possible public health consequences, regardless of whether such an incident derived from a deliberate act or a naturally occurring event. This overview gives a brief account of presentation made at the European Union “First Civil Protection Forum”, which was held in Brussels in November 2002, and which served as a basis for defining the EU priorities and actions to make Europe a safer place to live.Kao odgovor na napad na Sjedinjene Američke Države 11. rujna 2001, Regionalni ured za Europu Svjetske zdravstvene organizacije (SZO) odmah je poduzeo nekoliko koraka kako bi bio spreman da pomogne državama u slučaju terorističkog napada. Među ostalim, SZO je organizirao niz različitih konzultacija s međunarodnim organizacijama, predstavnicima država i ekspertima s ciljem da se procijeni stupanj pripreme na nacionalnoj i međunarodnoj razini, da se identificiraju glavni problemi, te da se donesu preporuke. Tim problemima pristupilo se u kontekstu mogućih posljedica na javno zdravstvo, neovisno o tome da li se radi o namjernom aktu ili prirodno nastalom slučaju. Ovaj pregled predstavlja kratki sadržaj uvodnog predavanja pripremljenog za “Prvi forum civilne zaštite” Europske unije, koji je održan u Bruxellesu u studenome 2002, a koji je poslužio kao osnova za definiranje prioriteta i akcija Europske unije, kako bi Europa postala sigurnije mjesto za život

Idiopathic Pancreatitis as a Rare Gastrointestinal Manifestation of Myotonic Muscular Dystrophy.

Myotonic muscular dystrophy (DM) is a multi-system disorder affecting skeletal muscles as well as smooth and cardiac muscles. Patients with DM experience disturbances in gastrointestinal motility; however, pancreatobiliary manifestations have rarely been described. We report the case of a 58-year-old male with MD who presented with a sudden onset of vomiting and abdominal pain. Laboratory and radiological findings were consistent with acute pancreatitis. No identifiable cause of pancreatitis could be identified despite an extensive workup. Sphincter of Oddi dysfunction (SOD) was felt to be the most likely cause of our patient\u27s acute pancreatitis. SOD leading to acute pancreatitis results from spasm of both the distal common biliary duct and the duct of Wirsung. It is a very rarely reported gastrointestinal manifestation of MD, but one that should not be overlooked

“The Past Got Broken Off”: Classifying “Indian” in the Indian Child Welfare Act

(Excerpt) In her 1993 novel, Pigs in Heaven, Barbara Kingsolver chronicles the story of an American Indian child, Turtle, and her young, white, adoptive mother, Taylor Greer. In what has been criticized as a controversial imagined fact pattern, Kingsolver writes that while stopped in a parking lot in the middle of the night, Taylor is approached by an American Indian woman holding a baby. Rather mysteriously, the woman informs Taylor that the baby’s mother died and the baby was being abused, upon which Taylor notes that “it looked like someone had been hurting [the woman] too.” After placing the baby in Taylor’s arms, the woman gets into an unlit car and drives off into the darkness. To her surprise, Taylor begins to bond with the child and eventually seeks to adopt her. However, when a Cherokee attorney, Annawakee, learns of the adoption, its legality is threatened by the ominous Indian Child Welfare Act (“ICWA”), which dictates (for the novel’s purposes) that “you can’t adopt an Indian kid without tribal permission.” The novel manages to capture—though not without an artistic license—the conflicting interests often involved in the adoption of an American Indian child by non-American Indians. The line between reality and representation is a thin one at best here, for the novel’s real-life counterpart is often just as dramatic and polarizing. Nevertheless, most American Indian children are not bestowed upon young women in the middle of the night, and Barbara Kingsolver—though certainly knowledgeable about American Indian issues—is a white woman from Maryland who has never adopted an American Indian child before. Much of what Kingsolver correctly shares, however, pertains to the history and intent of the ICWA. Annawakee describes the Act as a response to the “wholesale removal” of American Indian children through federal policies of “dividing up families” and “selling off land.” Indeed, this “wholesale removal” most notoriously took place during the “Boarding School Era,” when, from 1860 to 1973, American Indian families were coerced by the federal government into sending their children off-reservation to live at boarding schools. These government-run establishments aimed to introduce American Indian children to the “habits and arts of civilization” while forcing them to abandon their traditional languages, cultures, and practices. Although the policy was framed as a peaceful solution to the “Indian problem,” the boarding school era gave birth to the more well-known motto: “Kill the Indian, Save the Man.” Though the schools began closing their doors in the 1970s, the removal of American Indian children from their tribal lands persisted through their overrepresentation in the child welfare system. By 1973, 25-35% of all American Indian children nationwide were removed from their families, and 75-80% of American Indian families living on reservations lost at least one child to the foster care system

Impact of AIDS on the economy and health care services in Ethiopia

BackgroundAcquired immuno deficiency syndrome (AIDS) has been spreading at an alarming rate in Ethiopia after the first AIDS case in the country was reported in the mid-1980s. At the end of 1993, it was estimated that there were half a million people with AIDS and this number is expected to grow to more than five million by the year 2005 (1). It is obvious that the disease, unless effectively controlled, will result in a large number of illness and death of mostly the young. Its effect on the health care service system, which is inadequate to handle the traditional health problems, could not be negligible. The health status of Ethiopians, without the complications of AIDS, is very low as indicated by all health status indictors. The most important health status indicator, infant mortality rate, stands at 112 per 1000 live births. Only 27 percent of the people in 1994/95 had access to safe water. Life expectancy at birth stands at only 49 years. Maternal mortality rate per 100000 live births stood at 1525 in the period between 1989 and 1995. Prevalence rate of under-five malnu-trition was 47 percent, which is among the highest even in Africa (2)