Renewing the respect for similarity

In psychology, the concept of similarity has traditionally evoked a mixture of respect, stemming from its ubiquity and intuitive appeal, and concern, due to its dependence on the framing of the problem at hand and on its context. We argue for a renewed focus on similarity as an explanatory concept, by surveying established results and new developments in the theory and methods of similarity-preserving associative lookup and dimensionality reduction—critical components of many cognitive functions, as well as of intelligent data management in computer vision. We focus in particular on the growing family of algorithms that support associative memory by performing hashing that respects local similarity, and on the uses of similarity in representing structured objects and scenes. Insofar as these similarity-based ideas and methods are useful in cognitive modeling and in AI applications, they should be included in the core conceptual toolkit of computational neuroscience. In support of this stance, the present paper (1) offers a discussion of conceptual, mathematical, computational, and empirical aspects of similarity, as applied to the problems of visual object and scene representation, recognition, and interpretation, (2) mentions some key computational problems arising in attempts to put similarity to use, along with their possible solutions, (3) briefly states a previously developed similarity-based framework for visual object representation, the Chorus of Prototypes, along with the empirical support it enjoys, (4) presents new mathematical insights into the effectiveness of this framework, derived from its relationship to locality-sensitive hashing (LSH) and to concomitant statistics, (5) introduces a new model, the Chorus of Relational Descriptors (ChoRD), that extends this framework to scene representation and interpretation, (6) describes its implementation and testing, and finally (7) suggests possible directions in which the present research program can be extended in the future

Distribution of Disease-Causing Mutations through Different Protein Domains in Patients with Severe Combined Immunodeficiency

Background and Aim: Severe combined immunodeficiency (SCID) has been described as the most severe form of primary immunodeficiency disorders (PID). The disease can be caused by mutations in more than 20 different genes with prevalence of 1 in 50000 to 100000 live births. In the present study, we described the protein domain position of variants in 14 main genes in patients with SCID. We also aimed to investigate the correlation between the variant distribution of protein domains and its pathogenicity and clinical outcome of the variant. Materials and Methods: Molecular genetic analysis including Sanger sequencing, targeted gene panel and whole exome sequencing were performed on 50 patients with SCID. Moreover, protein domains characteristics were extracted from different databases such as Uniprot and PDB and the reported mutations were obtained from HGMD and ENSEMBL databases. Results: Our results showed that the mortality rate had a significant correlation with severity of clinical manifestations in the patients (p-value=0.000). There was also a significant relationship between the protein type and mutation severity (p-value=0.001) and severity of clinical manifestations (p-value=0.025). However, there was no significant relationship between the mortality rate and occurrence of mutations in different domains of proteins (p-value=0.304) and the severity of mutations (p-value= 0.586). Conclusion: In severe genetic diseases such as SCID, mutations in related genes have affected the structure of the protein enough to cause severe symptoms. However, there are differences in the pathogenicity of the mutations based on their location on the protein domains. In order to determine these variations and predict the outcome of mutations, it is necessary to use in silico and laboratory methods along with statistical and data mining tools to track these minor differences

KINEMATIC AND KINETIC COMPARISONS BElWEEN SPOT, CROSSOVER AND UPWARD JUMP THROWINGS IN HANDBALL

Throwing is one of the most important skills in handball in which two basic factors are of importance with regard to the efficiency of shots Le. accuracy and velocity. A 2Dimensional analysis of different throws Le. on the spot, with a cross-over step, and with upward jump has been undertaken. Eighteen high-performance handball players took part in this study. The average values of basic parameters of physical characteristics of subjects were: 80.2 ± 6.1 Kg (body mass), 184.8 ± 4 cm (body height), and 19.79 ± 0.63 years of age. The main aim of present study was to establish a valuable kinematic and kinetic comparison between different types of throws in handball. Statistically significant differences were found between maximal ban velocity during throws with cross-over step and ball velocity during other analyzed throws. In addition to the high velocity in this throw, the energy and power consumptions were also higher in magnitude comparing with other throws. The results obtained by this study agreed well with the results reported by other researchers

The current applications of cell-free fetal DNA in prenatal diagnosis of single-gene diseases: A review

Prenatal diagnosis of hereditary diseases has substantially altered the way medical geneticists are helping families affected by genetic disorders. However, the risk of miscarriage and fear of invasive diagnostic procedures may discourage many couples from seeking prenatal diagnosis. With the discovery of maternal plasma cell-free fetal DNA, prenatal diagnosis has entered a new era of progress. Cell-free DNA is released during normal physiological functions as well as through the cell death programs of apoptosis and necrosis. It can be found in the plasma and other body fluids. Although this method has the advantage of being noninvasive, it is still rather expensive and requires advanced hardware and comprehensive data analysis. Promising implications of noninvasive prenatal diagnosis methods for the diagnosis of common trisomy disorders have paved the way for the development of more complicated assays of single-gene disorders. Relative mutation dosage and relative haplotype dosage are the most widely implemented assays for noninvasive prenatal diagnosis of single-gene disorders. However, each assay has its own advantages and disadvantages. Relative mutation dosage is based on the droplet digital polymerase chain reaction (PCR) technique which includes quantification features of real-time PCR assays. Relative haplotype dosage is based on next-generation sequencing that includes analysis of the maternal and paternal genome followed by sequencing of maternal plasma cell-free DNA. Co-amplification at a lower denaturation temperature PCR is another approach that is based on forming heteroduplexes between alleles to selectively amplify paternal mutations. In this review, we have described the most common noninvasive prenatal diagnosis approaches and compared their applications in genetic disorder diagnosis with different inheritance patterns. Key words: Cell-free nucleic acids, Prenatal diagnosis, Noninvasive prenatal testing, Single-gene diseases, Non-invasive techniques

Zero tension Kardar-Parisi-Zhang equation in (d+1)- Dimensions

The joint probability distribution function (PDF) of the height and its gradients is derived for a zero tension $d+1$-dimensional Kardar-Parisi-Zhang (KPZ) equation. It is proved that the height`s PDF of zero tension KPZ equation shows lack of positivity after a finite time $t_{c}$. The properties of zero tension KPZ equation and its differences with the case that it possess an infinitesimal surface tension is discussed. Also potential relation between the time scale $t_{c}$ and the singularity time scale $t_{c, \nu \to 0}$ of the KPZ equation with an infinitesimal surface tension is investigated.Comment: 18 pages, 8 figure