scholarly journals On Promoters/Inhibitors and Symport/Antiport with Traces in P Systems

Triangle ◽  
2018 ◽  
pp. 67
Author(s):  
Mihai Ionescu
Keyword(s):  
Direct Relationship ◽  
The Other ◽  
P Systems ◽  
P System ◽  
Infinite Hierarchy ◽  
Recursively Enumerable ◽  
Computational Universality ◽  
The One ◽  
Recursively Enumerable Languages

This article brings together some rather powerful results on P systems in which the computation is performed by the communication of objects through symport and antiport rules considering the trace of an object through membranes, on the one hand, and by P systems with object-rewriting non-cooperative rules, promoters/inhibitors at the level of rules and only one catalyst, on the other. It is recalled here that computational universality can be reached whit these formalisms and that some of the proofs can be sketched. Three ideas are also put forward to brake the direct relationship (infinite hierarchy) induced by the size of the considered alphabet and the number of the membranes needed in a P system (with traces) to generate recursively enumerable languages on the chosen alphabet.

COMPUTING WITH MEMBRANES (P SYSTEMS): A VARIANT

2000 ◽  
Vol 11 (01) ◽  
pp. 167-181 ◽  
Author(s):  
GHEORGHE PĂUN
Keyword(s):  
Membrane Computing ◽  
P Systems ◽  
Open Problems ◽  
Recursively Enumerable ◽  
Pass Through ◽  
The One ◽  
Priority Relation ◽  
Recursively Enumerable Languages ◽  
Biochemical Features ◽  
Computing Models

Membrane Computing is a recently introduced area of Molecular Computing, where a computation takes place in a membrane structure where multisets of objects evolve according to given rules (they can also pass through membranes). The obtained computing models were called P systems. In basic variants of P systems, the use of objects evolution rules is regulated by a given priority relation; moreover, each membrane has a label and one can send objects to precise membranes, identified by their labels. We propose here a variant where we get rid of both there rather artificial (non-biochemical) features. Instead, we add to membranes and to objects an "electrical charge" and the objects are passed through membranes according to their charge. We prove that such systems are able to characterize the one-letter recursively enumerable languages (equivalently, the recursively enumerable sets of natural numbers), providing that an extra feature is considered: the membranes can be made thicker or thinner (also dissolved) and the communication through a membrane is possible only when its thickness is equal to 1. Several open problems are formulated.

PROBABILISTIC REWRITING P SYSTEMS

2003 ◽  
Vol 14 (01) ◽  
pp. 157-166 ◽  
Author(s):  
MUTYAM MADHU
Keyword(s):  
P Systems ◽  
Cut Point ◽  
Recursively Enumerable ◽  
The Family ◽  
Rewriting Rules ◽  
Recursively Enumerable Languages ◽  
Selection Of

In this paper we define a variant of P systems, namely, probabilistic rewriting P systems, where the selection of rewriting rules is probabilistic. We show that, with non-zero cut-point, probabilistic rewriting P systems with/without priorities generate only finite languages, but with zero cut/point and without priorities, probabilistic rewriting P systems of degree 1 characterize the family of languages generated by matrix grammars. We also prove that probabilistic rewriting P systems of degree 1 with zero cut-point and priorities characterize recursively enumerable languages.

Contemplated Suicide among Voluntary and Involuntary Retirees

1979 ◽  
Vol 9 (2) ◽  
pp. 193-201 ◽  
Author(s):  
Peter O. Peretti ◽  
Cedric Wilson
Keyword(s):  
Direct Relationship ◽  
The Other ◽  
Involuntary Retirement ◽  
The One

This study explored anomic and egoistic dimensions of contemplated suicide among voluntary and involuntary retired males. Significant differences were found in the participants' contemplation of suicide when considering degrees of anomie and egoism. Results indicated a direct relationship between anomie and egoism on the one hand, and contemplation of suicide on the other. Involuntary retirement tended to increase the probability of contemplated suicide under each condition.

scholarly journals Periorbital Hyperpigmentation, a Dermatologic Condition Having a Strong Geographic and Ethnic Determinism

2018 ◽  
Author(s):  
Felicia Andrei ◽  
Daciana Grujic ◽  
Cristina Lazar ◽  
Anca Dragomirescu
Keyword(s):  
Minimally Invasive ◽  
Social Integration ◽  
Direct Relationship ◽  
Lower Eyelid ◽  
Skin Aging ◽  
The Other ◽  
Therapeutic Decision ◽  
The One ◽  
A Minor ◽  
Surgical Treatments

POH (Peri Orbital Hyperpigmentation) represents a minor clinical entity that attracts immense aesthetic damages and it generates social integration difficulties. This review focuses on the etiopathogenic causes of this entity, differentiating and reclassifying this defect as having, on the one hand, genetic causes of melanic hyperproduction – for Fitzpatrick cutaneous phototypes IV and V – and, on the other hand, both genetic and acquired vascular causes, in individuals with light-coloured skin phototypes. Hence, there is a big difference in the field of pathogenic treatment, for the two entities. In addition, this study notes the direct relationship between skin aging and POH, especially for aquired vascular causes. In this reasoning, other aesthetic deficiencies of the skin in the palpebral area should be also considered, like: blepharochalasis, wrinkles, the anatomical causes of the lower eyelid shading, symmetrical or asymmetric suborbital oedema. All of these issues will complicate the therapeutic decision and subsidiary, the pharmaceutical advice. In this context, the review shows the guidelines for a honest councelling of the patients, pointing the efficiency limit for the topical pharmaceutical medication (depigmentants, exfoliants) versus the necessity of minimally invasive or/ and surgical treatments (in blefarochalasis).

scholarly journals Variants of derivation modes for which catalytic P systems with one catalyst are computationally complete

2021 ◽  
Author(s):  
Artiom Alhazov ◽  
Rudolf Freund ◽  
Sergiu Ivanov ◽  
Sergey Verlan
Keyword(s):  
Computational Complexity ◽  
P Systems ◽  
P System ◽  
Membrane Systems ◽  
Energy Control ◽  
Computational Completeness ◽  
Current Configuration ◽  
Recursively Enumerable ◽  
Completeness Result ◽  
Recursively Enumerable Sets

AbstractCatalytic P systems are among the first variants of membrane systems ever considered in this area. This variant of systems also features some prominent computational complexity questions, and in particular the problem of using only one catalyst: is one catalyst enough to allow for generating all recursively enumerable sets of multisets? Several additional ingredients have been shown to be sufficient for obtaining even computational completeness with only one catalyst. Last year we could show that the derivation mode $$max_{objects}$$ m a x objects , where we only take those multisets of rules which affect the maximal number of objects in the underlying configuration one catalyst is sufficient for obtaining computational completeness without any other ingredients. In this paper we follow this way of research and show that one catalyst is also sufficient for obtaining computational completeness when using specific variants of derivation modes based on non-extendable multisets of rules: we only take those non-extendable multisets whose application yields the maximal number of generated objects or else those non-extendable multisets whose application yields the maximal difference in the number of objects between the newly generated configuration and the current configuration. A similar computational completeness result can even be obtained when omitting the condition of non-extendability of the applied multisets when taking the maximal difference of objects or the maximal number of generated objects. Moreover, we reconsider simple P system with energy control—both symbol and rule energy-controlled P systems equipped with these new variants of derivation modes yield computational completeness.

scholarly journals Blockchain: A mechanism of “unorthodox” trust

2019 ◽  
Vol 2 (1) ◽  
pp. 50
Author(s):  
Valentini Grigoriadou
Keyword(s):  
Higher Education ◽  
Direct Relationship ◽  
Hierarchical Structures ◽  
The Other ◽  
Data Bases ◽  
Psychological Reality ◽  
The Core ◽  
New Type ◽  
The One ◽  
Central Data

Blockchain is a revolutionary technology which is expected to cut off proxies, reduce cost and increase speed and range. It offers transparency, safety and traceability and considerable high levels of trust. In contrast with traditional hierarchical structures and central data-bases where trust lies within institutions, blockchain’s trust is technology. It could possibly constitute the core of a new type of internet. The fact that it is developing rapidly in various fields simultaneously, will inevitably change the way of communication in the future. Although, since its onset, it was mainly used for financial exchange; it becomes evident that it is applicable in every form of exchange. Thus the new digital trust through encryption could have a determining role in redeveloping higher education. In such a context, students, instructors and teachers are in direct relationship with one another; as a result new forms of interaction are generated. The main objective is to examine on the one hand blockchain’s application in the educational sector, focusing on its potential to change educational mechanisms for the better and on the other hand its reception and the influence this technology could have on the socio-psychological reality of the involved subjects. Its application on the field of education will undoubtedly be beneficial but it is an imperative that we inspect any potential dangers as well. Since people have the need of an institution that they can trust, the creation of a world of decentralised trust is a challenge.

The Khandesh Survey Riots of 1852: Government policy and rural society in Western India

1968 ◽  
Vol 100 (2) ◽  
pp. 151-165
Author(s):  
J. F. M. Jhirad
Keyword(s):  
Social Change ◽  
19Th Century ◽  
Government Policy ◽  
Direct Relationship ◽  
Rural Society ◽  
The Other ◽  
Land Policy ◽  
Western India ◽  
The Government ◽  
The One

The traditional forms of landholding and the government's land policy are two problems in the study of the nature of social change in 19th-century Western India; as the necessary aetiology of agrarian movements they are also linked with the organization and idiom of popular protest on the one hand, and the structure and temper of official institutions on the other. The Khandesh Survey riots are a microcosm of these problems as they existed in a raīyatwārī (peasant-proprietary) area of the Bombay Presidency, five years before the Mutiny. An analysis of the agrarian relations—partly as seen articulated in the movement of the riots—seems to have an undiminished relevance for later periods, and may perhaps qualify an impression of the Bombay raīyatwārī system as one where the government as landlord had a uniformly direct relationship with a standard cultivatortenant.

scholarly journals Efficient computation in rational-valued P systems

2009 ◽  
Vol 19 (6) ◽  
pp. 1125-1139
Author(s):  
NADIA BUSI ◽  
MIGUEL A. GUTIÉRREZ-NARANJO ◽  
MARIO J. PÉREZ-JIMÉNEZ
Keyword(s):  
Linear Algebra ◽  
Membrane Computing ◽  
The Other ◽  
P Systems ◽  
Efficient Computation ◽  
Other Hand ◽  
The One

In this paper, we describe a new representation for deterministic rational-valued P systems that allows us to form a bridge between membrane computing and linear algebra. On the one hand, we prove that an efficient computation for these P systems can be described using linear algebra techniques. In particular, we show that the computation for getting a configuration in such P systems can be carried out by multiplying appropriate matrices. On the other hand, we also show that membrane computing techniques can be used to get the nth power of a given matrix.

Author's characters and the character of the author: The typical in fiction

2011 ◽  
Vol 40 (2) ◽  
Author(s):  
Tahir Wood
Keyword(s):  
Direct Relationship ◽  
Point Of View ◽  
The Other ◽  
Specific Reference ◽  
Fictional Characters ◽  
The Novel ◽  
Fictional World ◽  
John Fowles ◽  
The Social ◽  
The One

AbstractThis article situates the semantics of fictional characters within a broader framework of authorial communication. It argues that theories of character in the novel will be deficient to the extent that characters are not conceptualised as motivated creations of an author. The influential approach of Georg Lukács effectively excluded the point of view of the author in favour of a direct relationship between the fictional work and processes of history, as an instance of the particular related to the universal. But here it is argued that the notion of the typical should rather be seen as a relation between the social milieu of the authorial experience on the one hand and the figure-ground construction of character on the other. This constitutes part of a project to examine the question of realism on a renewed basis, particularly in terms of the authorial presence within the fictional world, and the case is argued with specific reference to a novel by John Fowles.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

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