scholarly journals REWRITING WITH STRATEGIES IN $\mathsf{ELAN}$: A FUNCTIONAL SEMANTICS

2001 ◽  
Vol 12 (01) ◽  
pp. 69-95 ◽  
Author(s):  
PETER BOROVANSKÝ ◽  
CLAUDE KIRCHNER ◽  
HÉLÈNE KIRCHNER ◽  
CHRISTOPHE RINGEISSEN

In this work, we consider term rewriting from a functional point of view. A rewrite rule is a function that can be applied to a term using an explicit application function. From this starting point, we show how to build more elaborated functions, describing first rewrite derivations, then sets of derivations. These functions, that we call strategies, can themselves be defined by rewrite rules and the construction can be iterated leading to higher-order strategies. Furthermore, the application function is itself defined using rewriting in the same spirit. We present this calculus and study its properties. Its implementation in the [Formula: see text] language is used to motivate and exemplify the whole approach. The expressiveness of [Formula: see text] is illustrated by examples of polymorphic functions and strategies.

2007 ◽  
Vol 17 (3) ◽  
pp. 363-406 ◽  
Author(s):  
PAOLO BALDAN ◽  
CLARA BERTOLISSI ◽  
HORATIU CIRSTEA ◽  
CLAUDE KIRCHNER

The Rewriting Calculus (ρ-calculus, for short) was introduced at the end of the 1990s and fully integrates term-rewriting and λ-calculus. The rewrite rules, acting as elaborated abstractions, their application and the structured results obtained are first class objects of the calculus. The evaluation mechanism, which is a generalisation of beta-reduction, relies strongly on term matching in various theories.In this paper we propose an extension of the ρ-calculus, called ρg-calculus, that handles structures with cycles and sharing rather than simple terms. This is obtained by using recursion constraints in addition to the standard ρ-calculus matching constraints, which leads to a term-graph representation in an equational style. Like in the ρ-calculus, the transformations are performed by explicit application of rewrite rules as first-class entities. The possibility of expressing sharing and cycles allows one to represent and compute over regular infinite entities.We show that the ρg-calculus, under suitable linearity conditions, is confluent. The proof of this result is quite elaborate, due to the non-termination of the system and the fact that ρg-calculus-terms are considered modulo an equational theory. We also show that the ρg-calculus is expressive enough to simulate first-order (equational) left-linear term-graph rewriting and α-calculus with explicit recursion (modelled using a letrec-like construct).


Author(s):  
F. Semprucci ◽  
P. Colantoni ◽  
C. Sbrocca ◽  
G. Baldelli ◽  
M. Balsamo

Huvadhoo Atoll is a little-known and generally uncontaminated atoll of the southern Maldives, although the human pressure is increasing. This study represents the first attempt to characterize the meiofaunal and nematode assemblages of its lagoon both from a taxonomic and functional point of view. The nematode assemblage was made up of a total of 131 genera in 33 families. Desmodoridae, Chromadoridae and Xyalidae represented the richest and most abundant families, followed in terms of abundance by Selachinematidae and Comesomatidae. The nematode richness was overall higher than that reported in the previous studies carried out in the Central part of the archipelago. The diversity patterns revealed higher values than those reported for the back-reefs platforms, so confirming the positive influence of the water depth on the biodiversity of the nematode assemblage. The statistical analysis highlighted a significant taxonomic difference of the assemblages between the stations characterized by fine and medium-coarse sands, respectively, in line with the auto-ecological preferences of the taxa detected. The use of some nematode descriptors for assessing the ecological quality status (EQS) of the lagoon has revealed a slight disturbance in the station close to Viligili, one of the most urbanized islands. However, the summarization of all the descriptors used allows the highlighting of the good EQS of the Huvadhoo lagoon. Thus, the results of this study may be taken as the starting point for the future monitoring of the potential and real impact of the anthropogenic activity on the area over time.


Trictrac ◽  
2016 ◽  
Vol 9 ◽  
Author(s):  
Liliana Danciu ◽  
Petru Adrian Danciu

The axes of the creation and birth of the imaginary as a mythical language. Our research follows the relationships of the concepts that are taking into account creation on the double axis of verticality and horizontality. We highlight those symbolic elements which would later constitute the mythical language about the sacred space-temporality. Inside this space-temporality a rich spectrum of mythical images develops; images capable of explaining the relationships of the creation plans. Without a religious perception of the temporality, the conceptualization of the axis would remain a philosophical approach. Through our point of view, the two are born simultaneously. Thanks to them, creation can be imagined. The first “frozen” formula of the mystical human spirit can be thought, brought to a palpable reality, expressed in an oral and then a written form. Studied together, temporality (sacred or not) and space are permanently imagined together. For example, a loss of mundane temporality in the secret ecstasy that offers to the soul an ascending direction does not mean getting out of universal temporality, but of its mundane section. In the sacred space the soul relates to time. Even the gods are submitted by the sacred, Aeon sometimes being synonymous to destiny. The universal creator seems to evade every touch, but not consistently, only when he avoids the descent into its created worlds. In sacredness, time and space seem or become confused, both expressing the same reality, by the immediate swing from thinking to deed. The mythical imagery conceives the displacement in the primary space-temporality by the spoken word. So, for something to appear and live, the spoken word is required. Even the divine dream appears as a pre-word of a creator’s thought. The thought follows the spoken word, the spoken word follows the gestures which finally indicate the meanings of the creative act, controlling the rhythm of the creation days. These three will later be adapted through imitation in rite. We are now situated at the limit of the physical world, a real challenge for the mythical imagery. The general feature of the mythical expression on the creation of the material world is the state of the divinity’s exhaustion, most often conceptualized by sacrifice or divine fatigue. The world geography identifies with the anatomy of a self-gutted god. Practically, material creation is most likely the complete revelation of God’s body autopsy. As each body decomposes, everything in it is an illusion. An axial approach of the phenomenon exists in all religious systems. The created element’s origin is exterior, with or without a pre-existing matter, by a god’s sacrifice or only because it has to be that way. This is the starting point of the discussion on the symbolism of axiality as a reason for the constitution of the language of creation, capable of retelling the imaginary construction of myth in an oral and then written form.


2012 ◽  
pp. 66-80
Author(s):  
Michał Mrozowicki

Michel Butor, born in 1926, one of the leaders of the French New Novel movement, has written only four novels between 1954 and 1960. The most famous of them is La Modification (Second thoughts), published in 1957. The author of the paper analyzes two other Butor’s novels: L’Emploi du temps (Passing time) – 1956, and Degrés (Degrees) – 1960. The theme of absence is crucial in both of them. In the former, the novel, presented as the diary of Jacques Revel, a young Frenchman spending a year in Bleston (a fictitious English city vaguely similar to Manchester), describes the narrator’s struggle to survive in a double – spatial and temporal – labyrinth. The first of them, formed by Bleston’s streets, squares and parks, is symbolized by the City plan. During his one year sojourn in the city, using its plan, Revel learns patiently how to move in its different districts, and in its strange labyrinth – strange because devoid any centre – that at the end stops annoying him. The other, the temporal one, symbolized by the diary itself, the labyrinth of the human memory, discovered by the narrator rather lately, somewhere in the middle of the year passed in Bleston, becomes, by contrast, more and more dense and complex, which is reflected by an increasinly complex narration used to describe the past. However, at the moment Revel is leaving the city, he is still unable to recall and to describe the events of the 29th of February 1952. This gap, this absence, symbolizes his defeat as the narrator, and, in the same time, the human memory’s limits. In Degrees temporal and spatial structures are also very important. This time round, however, the problems of the narration itself, become predominant. Considered from this point of view, the novel announces Gerard Genette’s work Narrative Discourse and his theoretical discussion of two narratological categories: narrative voice and narrative mode. Having transgressed his narrative competences, Pierre Vernier, the narrator of the first and the second parts of the novel, who, taking as a starting point, a complete account of one hour at school, tries to describe the whole world and various aspects of the human civilization for the benefit of his nephew, Pierre Eller, must fail and disappear, as the narrator, from the third part, which is narrated by another narrator, less audacious and more credible.


2018 ◽  
Vol 28 (6) ◽  
pp. 1993-2005
Author(s):  
Shemsije Demiri ◽  
Rudina Kaja

This paper deals with the right to property in general terms from its source in Roman law, which is the starting point for all subsequent legal systems. As a result of this, the acquisition of property rights is handled from the historical point of view, with the inclusion of various local and international literature and studies, as well as the legal aspect devoted to the respective civil codes of the states cited in the paper.Due to such socio-economic developments, state ownership and its ownership function have changed. The state function as owner of property also changed in Macedonia's property law.The new constitutional sequence of the Republic of Macedonia since 1991 became privately owned as a dominant form of ownership, however, state ownership also exists.This process of transforming social property into state or private (dissolves), in Macedonia starts from Yugoslavia through privatization, return and denationalization measures, on which basis laws on privatization have been adopted. Because of this, there will be particularly intensive negotiations regaring the remaining state assets.


2018 ◽  
Vol 69 (8) ◽  
pp. 2191-2196
Author(s):  
Cristian Constantin Budacu ◽  
Nicoleta Ioanid ◽  
Cristian Romanec ◽  
Mihail Balan ◽  
Liliana Lacramioara Pavel ◽  
...  

Canine plays an important role in the dento-maxillary system. From a functional point of view, it provides the canine guidance, by positioning it in the frontal area, has a role in facial aesthetics. It plays an important prosthetic role by having the longest root and one of the longest arcade teeth. Three molars represent the last teeth that erupt in the arches both in the jaw and in the mandible, which is why they remain the most frequently included.Canine incidence is quite common following the wisdom tooth. It can be unilateral or bilateral and is more common in the upper jaw. The canine may remain included at the vestibular, palatal or between the two bones. A separate entity is the incision of the canine in the edentulous mandible or jaw. The study included 213 cases with dento-alveolar pathology, of which 128 patients were selected with dental inclusion. Our study reports that the first three molars are frequent, followed by the canine as opposed to other studies conducted by Guzduz K in 2011 and Fardi A of the same year bringing the canines first (Fardi, Guzduz). Some studies attribute the first place to the superior canine in terms of frequency, but they are abstracted from the molar three inclusion that they consider as most frequently (Compoy). The most common tooth in inclusion is the third molar (lower and upper) followed by the upper canine; the most commonly affected are women for both canine and molar.


2020 ◽  
Vol 27 (5) ◽  
pp. 400-410
Author(s):  
Valentina De Luca ◽  
Luigi Mandrich

: Enzymes are among the most studied biological molecules because better understanding enzymes structure and activity will shed more light on their biological processes and regulation; from a biotechnological point of view there are many examples of enzymes used with the aim to obtain new products and/or to make industrial processes less invasive towards the environment. Enzymes are known for their high specificity in the recognition of a substrate but considering the particular features of an increasing number of enzymes this is not completely true, in fact, many enzymes are active on different substrates: this ability is called enzyme promiscuity. Usually, promiscuous activities have significantly lower kinetic parameters than to that of primary activity, but they have a crucial role in gene evolution. It is accepted that gene duplication followed by sequence divergence is considered a key evolutionary mechanism to generate new enzyme functions. In this way, promiscuous activities are the starting point to increase a secondary activity in the main activity and then get a new enzyme. The primary activity can be lost or reduced to a promiscuous activity. In this review we describe the differences between substrate and enzyme promiscuity, and its rule in gene evolution. From a practical point of view the knowledge of promiscuity can facilitate the in vitro progress of proteins engineering, both for biomedical and industrial applications. In particular, we report cases regarding esterases, phosphotriesterases and cytochrome P450.


2020 ◽  
Vol 16 (6) ◽  
pp. 784-795
Author(s):  
Krisnna M.A. Alves ◽  
Fábio José Bonfim Cardoso ◽  
Kathia M. Honorio ◽  
Fábio A. de Molfetta

Background:: Leishmaniosis is a neglected tropical disease and glyceraldehyde 3- phosphate dehydrogenase (GAPDH) is a key enzyme in the design of new drugs to fight this disease. Objective:: The present study aimed to evaluate potential inhibitors of GAPDH enzyme found in Leishmania mexicana (L. mexicana). Methods: A search for novel antileishmanial molecules was carried out based on similarities from the pharmacophoric point of view related to the binding site of the crystallographic enzyme using the ZINCPharmer server. The molecules selected in this screening were subjected to molecular docking and molecular dynamics simulations. Results:: Consensual analysis of the docking energy values was performed, resulting in the selection of ten compounds. These ligand-receptor complexes were visually inspected in order to analyze the main interactions and subjected to toxicophoric evaluation, culminating in the selection of three compounds, which were subsequently submitted to molecular dynamics simulations. The docking results showed that the selected compounds interacted with GAPDH from L. mexicana, especially by hydrogen bonds with Cys166, Arg249, His194, Thr167, and Thr226. From the results obtained from molecular dynamics, it was observed that one of the loop regions, corresponding to the residues 195-222, can be related to the fitting of the substrate at the binding site, assisting in the positioning and the molecular recognition via residues responsible for the catalytic activity. Conclusion:: he use of molecular modeling techniques enabled the identification of promising compounds as inhibitors of the GAPDH enzyme from L. mexicana, and the results obtained here can serve as a starting point to design new and more effective compounds than those currently available.


1967 ◽  
Vol 113 (501) ◽  
pp. 813-822 ◽  
Author(s):  
Örnulv Ödegård

My choice of Kraepelin as a point of departure for this lecture has definite reasons. If one wants to stay within the field of clinical psychiatry (as opposed to psychiatric history), that is as far back as one can reasonably go. By this no slight is intended upon the pre-Kraepelinian psychiatrists. For our topic Henry Maudsley would indeed have been a most appropriate starting point, and by no means for reasons of courtesy. His general point of view is admirably sound as a basis for the scientific study of prognosis in psychiatry. I quote: “There is no accident in madness. Causality, not casualty, governs its appearance in the universe, and it is very far from being a good and sufficient practice simply to mark its phenomena and straightway to pass on as if they belonged not to an order but to a disorder of events that called for no explanation.” On the special problem of prognosis he shows his clinical acumen by stating that the outlook is poor when the course of illness is insidious, but this only means that these cases develop their psychoses on the basis of mental deviations which go very far back in the patient's life, so that in fact they are generally in a chronic stage at the time of their first admission to hospital. Here he actually corrects a mistake which is still quite often made. He shows his dynamic attitude when he says that prognosis is to a large extent modified by external conditions, in particular by the attitude of friends and relatives. Maudsley's dynamic reasoning was limited by the narrow framework of the degeneration hypothesis of those days. He had a sceptical attitude towards classification, which he regarded as artificial and dangerously pseudo-exact. His own classification was deliberately provisional, with very wide groups. He held that a description of various sub-forms of chronic insanity was useless, as it would mean nothing but a tiresome enumeration of unconnected details.


2020 ◽  
Vol 25 (3) ◽  
pp. 49
Author(s):  
Silvia Licciardi ◽  
Rosa Maria Pidatella ◽  
Marcello Artioli ◽  
Giuseppe Dattoli

In this paper, we show that the use of methods of an operational nature, such as umbral calculus, allows achieving a double target: on one side, the study of the Voigt function, which plays a pivotal role in spectroscopic studies and in other applications, according to a new point of view, and on the other, the introduction of a Voigt transform and its possible use. Furthermore, by the same method, we point out that the Hermite and Laguerre functions, extension of the corresponding polynomials to negative and/or real indices, can be expressed through a definition in a straightforward and unified fashion. It is illustrated how the techniques that we are going to suggest provide an easy derivation of the relevant properties along with generalizations to higher order functions.


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