scholarly journals Selective maintenance of multiple CRISPR arrays across prokaryotes

2017 ◽  
Author(s):  
Jake L. Weissman ◽  
William F. Fagan ◽  
Philip L.F. Johnson
Keyword(s):  
Immune System ◽  
Defense Mechanisms ◽  
Short Term Memory ◽  
Memory Span ◽  
Adaptive Immune System ◽  
Long Term Memory ◽  
Term Memory ◽  
Learning Speed ◽  
Single Organism ◽  
Multiple Copies

AbstractProkaryotes are under nearly constant attack by viral pathogens. To protect against this threat of infection, bacteria and archaea have evolved a wide array of defense mechanisms, singly and in combination. While immune diversity in a single organism likely reduces the chance of pathogen evolutionary escape, it remains puzzling why many prokaryotes also have multiple, seemingly redundant, copies of the same type of immune system. Here, we focus on the highly flexible CRISPR adaptive immune system, which is present in multiple copies in a surprising 28% of the prokaryotic genomes in RefSeq. We use a comparative genomics approach looking across all prokaryotes to demonstrate that, on average, organisms are under selection to maintain more than one CRISPR array. We hypothesize that a tradeoff between memory span and learning speed could select for both “long-term memory” and “short-term memory” CRISPR arrays, and we go on to develop a mathematical model to show that such a tradeoff could, in theory, lead to selection for multiple arrays.

Developmental systems and their dysfunction

2019 ◽  
pp. 254-272
Author(s):  
John C. Lucchesi
Keyword(s):  
Immune System ◽  
Lupus Erythematosus ◽  
Short Term Memory ◽  
Fragile X ◽  
Adaptive Immune System ◽  
Long Term Memory ◽  
Term Memory ◽  
New Information ◽  
Citrullinated Proteins ◽  
Infected Cells

A specific function performed by the brain is learning—new information is stored as short-term memory by the activation of the transcription factor CREB, and as long-term memory by DNA methylation and demethylation of specific genes. Learning also involves a neuron-specific remodeling complex (BAF) and several micro RNAs (miRNAs) and long non-coding (lncRNAs). Rubinstein–Taybi, Rett or fragile X syndromes, as well as Alzheimer’s, Parkinson’s or Huntington’s diseases, involve epigenetic alterations. Epigenetic misregulation occurs in cardiopathies such as Wolf–Hirschhorn and Kabuki syndromes. The innate immune system consists of cells that can destroy invading bacteria and virus-infected cells, and of circulating proteins that destroy pathogens. The adaptive immune system consists of macrophages and dendritic cells, T lymphocytes and B lymphocytes. Failure to recognize antigens as one’s own leads to autoimmune diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Cells from RA and SLE patients exhibit changes in histone acetyl transferases, deacetylases and methyl transferases, and in miRNAs. Arginines can be converted to citrulline, and citrullinated proteins are considered as non-self by the immune system. RA is characterized by the presence of autoantibodies against citrullinated peptides.

scholarly journals PENAMBAHAN SENAM OTAK PADA PROGRAM SENAM SEHAT ANAK INDONESIA (SSAI) DAPAT MENINGKATKAN MEMORI JANGKA PENDEK DAN INDEKS KESEGARAN JASMANI SISWA SD INPRES PONDANG

2019 ◽  
Author(s):  
Joanne Ingrid Robot ◽  
I Nyoman Adiputra ◽  
S. Indra Lesmana ◽  
Dewa Putu Sutjana ◽  
I Putu Adiartha Griadhi ◽  
...  
Keyword(s):  
Treatment Group ◽  
Physical Fitness ◽  
Short Term Memory ◽  
Memory Span ◽  
Wilcoxon Test ◽  
Control Group ◽  
Long Term Memory ◽  
Short Term ◽  
Term Memory ◽  
Brain Gym

ABSTRACTBackground: Short-term memory plays a role in all children's cognitive processes both in understanding the language, working on the task and problem-solving process. The speed of cognitive processes in children depend on the degree of activation of short-term memory. With stimulation that given in the form of brain-activating movements is expected to integrate short-term memory and long-term memory to generate new knowledge or expand the existing load in long-term memory. Cognitive function and academic achievement can also be influenced by the level of physical fitness. Physical fitness is very useful to support the physical capacity of children who in the end expected to improve his performance. Objective: This research was conducted to find out how big increase of short-term memory and physical fitness at the addition of Brain Gym in SSAI program at elementary school student of Inpres Pondang. Method: This research is true experimental, using two group pre and post test control group design. This research was conducted at SD Inpres Pondang, 3 times weekly for 6 weeks, at January 22, 2018 - March 05, 2018. The sample of research is 42 people divided into two groups. The Control Group in the form of SSAI program and the Treatment Group was given the addition of Brain Gym in the SSAI program. The measuring instrument used to memory span to measure short-term memory and TKJI to measure physical fitness. Results: The results of hypothesis testing using Wilcoxon test and Mann Whitney test. Wilcoxon test results showed short-term memory improvement in the treatment group significantly (p<0.05), the control group showed significant short-term memory increase (p<0.05). The result of hypothesis test shows the value of increase of physical fitness index in the treatment group significantly (p<0.05). The increase value of physical fitness index in control group significantly (p<0.05). Mann Whitney test results showed the value of span digits in the treatment group and control group with p=0.005 (p<0.05). Physical fitness value in treatment group and control group with p value = 0.091 (p>0.05). Conclusion: Statistically there is a difference in the addition of brain gymnastics to SSAI in increasing short-term memory of elementary students. Statistically there is no difference in the addition of brain gymnastics in SSAI in improving physical fitness in elementary school students.Keywords: Short term memory, physical fitness, memory span, Indonesian physical fitness test, brain gym, healthy gymnastics Indonesian children.

Conceptual short-term memory (CSTM) supports core claims of Christiansen and Chater

2016 ◽  
Vol 39 ◽  
Author(s):  
Mary C. Potter
Keyword(s):  
Working Memory ◽  
Rapid Serial Visual Presentation ◽  
Language Comprehension ◽  
Short Term Memory ◽  
Visual Presentation ◽  
Long Term Memory ◽  
Short Term ◽  
Term Memory ◽  
Use Of Knowledge

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.

Comparison of Auditory, Language, Memory, and Attention Abilities in Children With and Without Listening Difficulties

2020 ◽  
Vol 29 (4) ◽  
pp. 710-727
Author(s):  
Beula M. Magimairaj ◽  
Naveen K. Nagaraj ◽  
Alexander V. Sergeev ◽  
Natalie J. Benafield
Keyword(s):  
Auditory Processing ◽  
Short Term Memory ◽  
Group Differences ◽  
Long Term Memory ◽  
Short Term ◽  
Significant Group ◽  
Term Memory ◽  
Memory And Attention ◽  
Speed And Accuracy

Objectives School-age children with and without parent-reported listening difficulties (LiD) were compared on auditory processing, language, memory, and attention abilities. The objective was to extend what is known so far in the literature about children with LiD by using multiple measures and selective novel measures across the above areas. Design Twenty-six children who were reported by their parents as having LiD and 26 age-matched typically developing children completed clinical tests of auditory processing and multiple measures of language, attention, and memory. All children had normal-range pure-tone hearing thresholds bilaterally. Group differences were examined. Results In addition to significantly poorer speech-perception-in-noise scores, children with LiD had reduced speed and accuracy of word retrieval from long-term memory, poorer short-term memory, sentence recall, and inferencing ability. Statistically significant group differences were of moderate effect size; however, standard test scores of children with LiD were not clinically poor. No statistically significant group differences were observed in attention, working memory capacity, vocabulary, and nonverbal IQ. Conclusions Mild signal-to-noise ratio loss, as reflected by the group mean of children with LiD, supported the children's functional listening problems. In addition, children's relative weakness in select areas of language performance, short-term memory, and long-term memory lexical retrieval speed and accuracy added to previous research on evidence-based areas that need to be evaluated in children with LiD who almost always have heterogenous profiles. Importantly, the functional difficulties faced by children with LiD in relation to their test results indicated, to some extent, that commonly used assessments may not be adequately capturing the children's listening challenges. Supplemental Material https://doi.org/10.23641/asha.12808607

The Acute Effect of Alcohol on Various Memory Processes

2010 ◽  
Vol 24 (4) ◽  
pp. 249-252 ◽  
Author(s):  
Márk Molnár ◽  
Roland Boha ◽  
Balázs Czigler ◽  
Zsófia Anna Gaál
Keyword(s):  
Low Dose ◽  
Short Term Memory ◽  
Acute Effect ◽  
Long Term Memory ◽  
Term Memory ◽  
Memory Processes ◽  
Different Types ◽  
The Brain ◽  
Legal Consequences

This review surveys relevant and recent data of the pertinent literature regarding the acute effect of alcohol on various kinds of memory processes with special emphasis on working memory. The characteristics of different types of long-term memory (LTM) and short-term memory (STM) processes are summarized with an attempt to relate these to various structures in the brain. LTM is typically impaired by chronic alcohol intake but according to some data a single dose of ethanol may have long lasting effects if administered at a critically important age. The most commonly seen deleterious acute effect of alcohol to STM appears following large doses of ethanol in conditions of “binge drinking” causing the “blackout” phenomenon. However, with the application of various techniques and well-structured behavioral paradigms it is possible to detect, albeit occasionally, subtle changes of cognitive processes even as a result of a low dose of alcohol. These data may be important for the consideration of legal consequences of low-dose ethanol intake in conditions such as driving, etc.

The capacity of short term memory from an evolutionary perspective

2019 ◽  
Author(s):  
Majid Manoochehri
Keyword(s):  
Short Term Memory ◽  
Memory Span ◽  
Critical Role ◽  
Experimental Studies ◽  
Cognitive System ◽  
Evolutionary Approach ◽  
Evolutionary Perspective ◽  
Short Term ◽  
Term Memory

Memory span in humans has been intensely studied for more than a century. In spite of the critical role of memory span in our cognitive system, which intensifies the importance of fundamental determinants of its evolution, few studies have investigated it by taking an evolutionary approach. Overall, we know hardly anything about the evolution of memory components. In the present study, I briefly review the experimental studies of memory span in humans and non-human animals and shortly discuss some of the relevant evolutionary hypotheses.

scholarly journals An Approach toward the Development of a Functional Encoding Model of Short Term Memory during Reading

1978 ◽  
Vol 10 (2) ◽  
pp. 141-148
Author(s):  
Mary Anne Herndon
Keyword(s):  
Cluster Analysis ◽  
Storage Capacity ◽  
Short Term Memory ◽  
Long Term Memory ◽  
Short Term ◽  
Processing Efficiency ◽  
Term Memory ◽  
Information Unit ◽  
Subsequent Storage

In a model of the functioning of short term memory, the encoding of information for subsequent storage in long term memory is simulated. In the encoding process, semantically equivalent paragraphs are detected for recombination into a macro information unit. This recombination process can be used to relieve the limited storage capacity constraint of short term memory and subsequently increase processing efficiency. The results of the simulation give a favorable indication of the success for the use of cluster analysis as a tool to simulate the encoding function in the detection of semantically similar paragraphs.

Sign in / Sign up

Export Citation Format

Share Document