Top PDF Some algebraic and logical aspects of C∞-Rings

Some algebraic and logical aspects of C∞-Rings

Some algebraic and logical aspects of C∞-Rings

Conforme observado por I. Moerdijk e G. Reyes em [63], os an´ eis C ∞ tˆ em sido estudados especialmente tendo em vista suas aplica¸ c˜ oes em Teoria de Singularidades e para construir toposes que sirvam de modelos para a Geometria Diferencial Sint´ etica. Neste trabalho, seguimos um caminho complementar, aprofundando nosso conhecimento sobre eles por um vi´ es mais puro, fazendo uso da Teoria das Categorias e os analisando a partir de pontos de vistas alg´ ebrico e l´ ogico-categorial. Iniciamos o trabalho apresentando uma sistematiza¸c˜ ao abrangente dos fatos fundamentais da teoria (equacional) dos an´ eis C ∞ , distribu´ıdos aqui e ali na literatura atual - a maioria sem demonstra¸ c˜ oes - mas que servem de base para a teoria. Na sequˆ encia, desenvolvemos alguns t´ opicos do que denominamos ´ Algebra Comutativa C ∞ , expandindo resultados parciais de [66] e [67]. Realizamos um estudo sistem´ atico dos an´ eis C ∞ von Neumann-regulares - na linha do estudo alg´ ebrico realizado em [2]- e apresentamos alguns resultados interessantes a seu respeito, juntamente com sua rela¸ c˜ ao (funtorial) com os espa¸ cos booleanos. Estudamos algumas no¸c˜ oes pertinentes ` a Teoria de Feixes para an´ eis C ∞ , tais como espa¸ cos (localmente) C ∞ −anelados e o s´ıtio de Zariski liso. Finalmente, descrevemos toposes classificantes para a teoria (alg´ ebrica) dos an´ eis C ∞ , a teoria (coerente) dos an´ eis locais C ∞ e a teoria (alg´ ebrica) dos an´ eis C ∞ von Neumann regulares.
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CONCEPTUAL NEXUSES OF ALGEBRAIC KNOWLEDGE: A STUDY FROM THE STARTING POINT OF THE HISTORIC AND LOGICAL MOVEMENT

CONCEPTUAL NEXUSES OF ALGEBRAIC KNOWLEDGE: A STUDY FROM THE STARTING POINT OF THE HISTORIC AND LOGICAL MOVEMENT

The objective of this article is to present a reflection on what we have called conceptual nexuses of the algebraic knowledge from the historic and logical movement of the concepts. A conceptual nexus is defined as a link between the historic and logical forms of understanding the concept, which do not necessarily coincide with the different languages that express the concept. This study, of a theoretical character, was carried out by taking as singular some episodes highlighted in the history of algebra and acknowledging in their particularities (manifestations of language, thought forms, etc.) the conceptual nexuses that configure algebraic thought: the relationship among variable magnitudes in general. It was assumed that the knowledge of the historic and logical movement of algebraic concepts and its theoretical thought forms generate implications for the constitution of algebra’s teaching object and for the organization of teaching, thus contributing to overcome epistemological impasses in the appropriation of knowledge both by those who teach and those who learn.
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THE LOGICAL PHILOSOPHICAL ASPECTS OF THE ORGANIZATION OF KNOWLEDGE IN THE AREA OF INFORMATION SCIENCE :: Brapci ::

THE LOGICAL PHILOSOPHICAL ASPECTS OF THE ORGANIZATION OF KNOWLEDGE IN THE AREA OF INFORMATION SCIENCE :: Brapci ::

Abstract It presents the organization of knowledge through its philosophical and historical suppositions. It approaches questions such as the significant modalities, among which are the Aristotle´s categories and predictables and, consequently, and consequently the prominence of meaning, the knowledge trees with its hierarchical and universal structures, aiming at thinking over the fixed references of knowledge in modern times, influencing the classification theory, as well as the controlled language constructions. The present work is divided into the organization of knowledge, on its classical philosophical suppositions, its application in Ancient Times and Middle-Ages besides the improvement of the languages built during Modern Ages. It makes some considerations about the organization of knowledge in the post-modern times, and points out to a change on the “tagging” of the collaborative knowledge beyond the indexation operated by the robots from the search engines.
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Generalization of Neutrosophic Rings and Neutrosophic Fields

Generalization of Neutrosophic Rings and Neutrosophic Fields

Neutrosophy is a new branch of philosophy which studies the origin and features of neutralities in the nature. Floren- tin Smarandache in 1980 firstly introduced the concept of neutrosophic logic where each proposition in neutrosophic logic is approximated to have the percentage of truth in a subset T, the percentage of indeterminacy in a subset I, and the percentage of falsity in a subset F so that this neutro- sophic logic is called an extension of fuzzy logic. In fact neutrosophic set is the generalization of classical sets, con- ventional fuzzy set   1 , intuitionistic fuzzy set   2 and in- terval valued fuzzy set   3 . This mathematical tool is used to handle problems like imprecise, indeterminacy and in- consistent data etc. By utilizing neutrosophic theory, Vasantha Kandasamy and Florentin Smarandache dig out neutrosophic algebraic structures in   11 . Some of them are neutrosophic fields, neutrosophic vector spaces, neu- trosophic groups, neutrosophic bigroups, neutrosophic N- groups, neutrosophic semigroups, neutrosophic bisemi- groups, neutrosophic N-semigroup, neutrosophic loops, neutrosophic biloops, neutrosophic N-loop, neutrosophic groupoids, and neutrosophic bigroupoids and so on. In this paper we have tried to develop the the generalization of neutrosophic ring and neutrosophic field in a logical manner. Firstly, preliminaries and basic concepts are given for neutrosophic rings and neutrosophic fields. Then we presented the newly defined notions and results in neutrosophic birings and neutrosophic N-rings,
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Logical Aspects Regarding the Conception of Intelligent Systems

Logical Aspects Regarding the Conception of Intelligent Systems

Management implies a strong relation between the process and the management system, which must react to the events that occur. )n the given context, the management system bears certain A) features, if in the presence of some information of minimum orientation from the human governor; it can carry out complex actions as a response to the events from the outward environment. )ntelligence can include the ability to accept certain abstract specifications of tasks in a general form of purposes/restrictions and the production of some reasonable actions that agree with the specifications. )n any real-time A) system there is a fundamental compromise between the action and the reasoning. Time is a precious resource that uses up if the system must create reasoning over the actions before their execution. This time consumption can limit the number of the desired alternative actions and in this way the reasoning task becomes much more difficult to realise. )n certain cases, the lack of success of an action can be the most unfavourable solution, while in other cases any of the actions can be better that total lack of it. The necessary time for reasoning can warn us over certain delays or disasters. The efficiency of a real-time A) system depends on its ability to allocate reasoning efforts in concordance with the process situations. The process of allocation is most of the time a difficult process due to countless overloads of information. The visible state of the process is huge and can contain incomplete, contradictory or uncertain information, which entails the use of some modules in the structure of the management system as some problem-solving ones. Furthermore, this information is often changing. )t is actually impossible for a real-time system based on symbolic A) techniques to completely process all the information at a given moment and to choose a convenient type of reasoning, and to also respect all real-time restrictions.
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Some aspects of periodontitis pathogenesis in children

Some aspects of periodontitis pathogenesis in children

Abstract. Some aspects of periodontitis pathogenesis in children. Shcherbina I.N., Kovach I.V., Dychko Ye.N., Taran O.M. Inflammatory processes in the tissues surrounding tooth root are frequent enough and develop as the direct complication of caries. As acute periodontitis is manifested with grinding toothache and violation of physio- logical act of chewing, symptoms of general intoxication, the continuous sluggish chronic periodontitis is harmful and dangerous to the organism as well. It forms the state of chronic dontogenetic intoxication and chroneosepsis with wrong functioning of some internal organs and body systems. The like complications can cause significant disturbance to the function of kidneys, liver, heart, joints and their treatment without ablating focus of inflammation is often in- effective; this must be taken into account by doctors-interns. However, scanning of the oral cavity by conservative means has its difficulties mostly because of ignoring pathogenesis of such inflammation. That is why activity of ferments of blood dehydrogenases from the periapical tissues of the teeth affected with the chronic periodontitis was studied. The level of succinate dehydrogenase and alpha-glycerophosphate degydrogenase of lymphocytes of 110 schoolchildren aged 13-17 years old was studied. The main group of examined individuals included those of infected with tuber- culousis – 50 individuals, and the control group (60 individuals) – clinically healthy ones without tuberculousis desease. All schoolchildren had 1 or 2 teeth affected with chronic periodontitis of the apical localization. The re- searchers found that a significant inhibition of activity of succinate dehydrogenase and alpha-glycerophosphate degydrogenase ferments occurs in the inflammatory periodontal tissues, which indicates to local immunity decline, and as a consequence, pathogenic bacteria activation. In people infected with tuberculousis these violations were more developed. Such features of periodontitis pathogenesis must be taken into account when providing a combined treatment.
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Logical polysemy, event and argument structure of some German shootingbs

Logical polysemy, event and argument structure of some German shootingbs

In this paper we raise firstly inadequacies of the analysis of the verb to shoot by Croft (1998). Subsequently, we assign to this verb alternative configurations of base and profile according to the causal structure model (Croft, 1991, 1998) and the action chain model (Langacker, 1999). That forms the basis of a cognitive-grammatical description of a subset of the readings of the German verbs schießen, abschießen, anschießen, erschießen, totschießen and niederschießen. It will be suggested that these senses can be attributed to a large extent to functions, which are applied to verbal bases and profiles, and extend or shift these segments. Qualia structure of the verbs' complements are also considered. Aspects of the generative lexicon theory (Pustejovsky, 1995) are included in this way into the cognitive semantic analysis. Differently than proposed by Pustejovsky (1995), however, we plead for ordered rules, which erase certain arguments of a verb under certain conditions, instead of classifying these items according to their possibility of being omitted.
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Giving up logical atomism? Some remarks on Wittgenstein's Some Remarks on Logical Form

Giving up logical atomism? Some remarks on Wittgenstein's Some Remarks on Logical Form

In RLF Wittgenstein keeps his Tractarian presupposition that there should be exactly one logic: “We must eventually reach the ultimate connection of the terms, the immediate connection which cannot be broken without destroying the propositional form as such.” (RLF 162 f.) This position is still connected with logicism in the sense that we can ind something which is logically fundamental: “Such rules, however, cannot be laid down until we have actually reached the ultimate analysis of the phenomena in question. This, as we all know, has not yet been achieved.” (RLF 171) But putting numbers “into the structure of the atomic propositions themselves” and assuming any kind of coordinate system within logical space allow a kind of formal interaction between the structured atomic propositions and the coordinates of the logical space. One consequence is that some complex expressions are not allowed. Can we maintain logical atomism in the long run? Can we maintain at least some of its aspects?
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Some Aspects of Protozoan Infections in Immunocompromised Patients - A Review

Some Aspects of Protozoan Infections in Immunocompromised Patients - A Review

The most practical and easiest way of diagnosing cryptosporidiosis is the detection of parasite oocysts in feces or other body fluids. Various techniques have been used to visualize these oocysts, such as Ziehl-Neelsen staining, modified, Kinyoun carbolfuchsin staining, modi- fied, and staining with safranin-methylene blue and meth- enamine silver. Concentration methods, such as formalin- ether sedimentation or Sheather’s sugar flotation method, increase considerably the sensitivity of oocyst detection. The oocysts of this protozoon can be visualized in histo- logical sections of intestinal mucosa obtained by biopsy and stained with hematoxylin-eosin as single cells or grouped on the mucosal surface, i.e., at the brush border of the intestinal epithelium. More recent techniques us- ing fluorescent dyes such as acridine orange and auramine carbolfuchsin provided results comparable to those ob- tained with the staining methods described above for di- arrheic feces, and are able to detect parasites even in formed feces. Immunoenzymatic techniques (ELISA) us- ing monoclonal antibodies have shown a high degree of sensitivity and specificity for the detection of oocysts in feces and contaminated water (Costa-Cruz et al. 1996, Hoxie et al. 1997, Guerrant 1997, Griffiths 1998). Serologi- cal tests for the detection of antibodies represent an alter- native to parasitological methods for the diagnosis of cryptosporidiosis. Immunoenzymatic assays (ELISA) us- ing crude extract of ruptured oocysts as antigen have shown good sensitivity, although some studies have dem- onstrated that immunoblotting is much more sensitive and specific for antibody detection. In these cases, IgA type responses are observed which are directed against anti- gens found on the surface of sporozoites, the infectious form of the parasite; such antibodies seem to exert a pro- tective effect against symptomatic infection (Mooss et al. 1998, Eisemberg et al. 2001). A specific PCR has been de- veloped and may represent a better option for the diagno- sis of this infection in the future (Griffiths 1998).
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Algebraic aspects of tiling semigroups

Algebraic aspects of tiling semigroups

most, at their boundaries. Most interestingly, Penrose tilings [49] — famous because of their mathematical properties, such as the lack of translational symmetry — waited ten years to be found as the ideal models for certain quasicrystals [35]. Kellendonk’s application consisted in the construction of a non-commutative space and the corresponding C ∗ -algebra from a tiling. Two other papers by Kellendonk would follow. In [24], Kellendonk takes a different approach to the same problem. This time, the definition of a multiplicative structure on the classes of portions of the tiling, consisting of a finite union of tiles under translation, yield an almost-groupoid from which a topological groupoid is built. The reason why only the local structure of the tiling (that is, how the tiling looks on finite patches) matters has to do with the local nature of the interactions in the solid. Subsequently, a group assigned to this topological groupoid is going to provide, in theory at least, some information on the solid modelled by the tiling. The almost-groupoid associated to the tiling is precisely the ancestor of the tiling semigroup, a concept that would only be formulated later by Mark V. Lawson [32] (see also Kellendonk and Lawson [26]).
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Aspects of algebraic algebras

Aspects of algebraic algebras

Examples 3.7. A partially ordered set X is a split algebra for the downset monad if and only if X is completely distributive, in this case the map t : X → DX sends x ∈ X to the set {y ∈ X | y ≪ x} of all elements y ∈ Y which are totally below x (see [28, 17]). Similarly, a directed cocomplete partially ordered set X is a split algebra for I = (I, m, e) if and only if X is a domain (see Definition 2.5(4)); in this case the splitting t : X → IX is given by x 7→ {y ∈ X | y  x}. Regarding the filter monad F = (F, m, e) on Top 0 , a continuous lattice X (equipped with the Scott topology) is a split algebra for F if and only if X is F-disconnected in the sense of [19]. Here, with α : F X → X denoting the algebra structure of X, for an open subset A ⊆ X we put µ(A) = {x ∈ X | α(f) = x for some f ∈ F X with A ∈ f}. Then X is F-disconnected precisely when µ(A) is open, for every open subset A ⊆ X; and in this case the map t : X → F X sends x ∈ X to the filter t(x) = {A ⊆ X | A open, x ∈ µ(A)}. The case of the prime filter monad is similar, with µ(A) now defined using only prime filters. In terms of partially ordered compact Hausdorff spaces, every split algebra for F 2 is a Priestley space, more precise, a Priestley
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Constructions of algebraic lattices

Constructions of algebraic lattices

For obtain optimal packing lattices we need to find spheres whose centers are points of a lattice 3 and that the intersection of any two spheres is only a point. For the determination of the radius of these spheres, note that fixed k > 0, the intersection of the compact set {x ∈ R n ; |x| ≤ k} with the lattice 3 is a finite set. Therefore the number t = min{|x|; x ∈ 3, x 6= 0} is well defined. Furthermore, ρ(3) = t/2 is the greatest radius such that it is possible to obtain a packing lattice. If B (ρ(3)) is the sphere with center in the origin and radius ρ(3) then the packing density of 3 is defined by
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Predestination and human responsibility in medieval Islam : some aspects of a classical problem

Predestination and human responsibility in medieval Islam : some aspects of a classical problem

responsible for actions he or she was not able to perform of his or her own free will. Accountability implies the capacity on the part of that person to act autonomously. Therefore, God creates in us a power to act and to choose a course of action, opting between two opposites. Furthermore, it is God who makes available the causes through which we operate, and it is He who removes any obstacles precluding those acts. However, these are at- tributed to us rather than to God. We appropriate these actions by our will and with the concurrence of external causes. The external causes condition our choice of one of the opposites. This is explained in the following way: we desire something when we form an idea of it. Then we accept it. And this acceptance or assent (ta sdiq) is not due to our choice. The corollary of
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The ammonia synthesis: some historical aspects.

The ammonia synthesis: some historical aspects.

A empresa vienense Österreichische Chemische Werke, dirigida pelos irmãos R. e O. Margulies, em 1904 procurou Haber, ainda Privatdozent (título equivalente à nossa Livre-docência) em Karlsruhe para uma orientação e quiçá um desenvolvimento poste- rior sobre a fixação do nitrogênio. Inicialmente, Haber indicou Ostwald (Haber desconhecia o que houvera em 1900, inclusive o pedido de patente), porém parece que ele não se interessou. Haber então, com seu assistente Gabriel van Oordt, partindo dos resulta- dos de Ramsay e Young, realizou o seguinte experimento: passou uma corrente muito lenta de amônia sobre pó de ferro aquecido a 1000 °C e separou a amônia não decomposta; passou, a seguir, os gases obtidos na decomposição (nitrogênio e hidrogênio) sobre o mesmo catalisador e obteve uma quantidade de amônia muito pró- xima da não decomposta. Isto significou que ele atingiu o estado de equilíbrio partindo das “duas pontas”, ou seja, pela decomposição e pela síntese,
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Carnap's Principle of Tolerance and logical pluralism

Carnap's Principle of Tolerance and logical pluralism

In general terms, logical pluralism is the claim that there is more than one adequate, coherent, or even, true logic. Note that, from a pure abstract point of view, this thesis may seem trivial today. It’s obvious that there are different pure logics. But logical pluralism is not exactly, or not only, about this. It amounts to acknowledge, for instance, that given a certain domain, there are at least two logics that formalize it in a fundamentally different way. And that, nonetheless, both are equally adequate for this task. There are many kinds of logical pluralism (Cf. BEALL, RESTAL, 2006 and SHAPIRO, 2014), but that’s not really relevant for the moment. In a schematic way, a pluralist logician claims that exists situations such that
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Some historical aspects of the periodic classification of the chemical elements.

Some historical aspects of the periodic classification of the chemical elements.

As então chamadas “terras ítria e céria” foram estudadas entre os anos de 1839 e 1843 por Carl G. Mosander (1797- 1858), que mostrou não serem substâncias simples e sim mis- turas bastante complexas. Mosander conseguiu isolar da céria, em 1839, as substâncias simples dos elementos cério e lantânio, e da ítria, em 1843, as dos elementos ítrio, térbio e érbio. Em 1878, Jean Charles G. de Marignac (1817-1894) isolou o itérbio e, em 1880, o gadolínio. Em 1879, Boisbaudran isolou o samário e, em 1886, o disprósio. Também em 1879, Cleve evi- denciou a existência do hólmio e do tálio, e Nilson descobriu o escândio. Outros pesquisadores também conseguiram isolar no- vos elementos. Em 1885, confirmando suspeitas de outros pes- quisadores de que o didímio era uma mistura de elementos, o Barão Auer von Welsbach (1858-1929), químico austríaco, iso- lou o praseodímio (“didímio verde”) e o neodímio (“novo didímio”) a partir do didímio (do grego: “gêmeo”); posterior- mente (1907), em colaboração com Georges Urbain (1872-) e C. James, isolou o lutécio a partir da ítria. Em 1901, Eugène A. Demarçay (1852-1904) caracterizou a existência do európio 7,54 .
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Clinical and  aspects of Hepatitis B virus and Hepatitis C virus in FortalezaCeará

Clinical and aspects of Hepatitis B virus and Hepatitis C virus in FortalezaCeará

Because of its various forms of transmission, he- patitis remains circulating in the population. The most common forms of infection are sexual, pa- renteral and vertical [10]. However, other forms of transmission such as use of manicure tools, crack pipe and tools to inhale cocaine have been associa- ted with hepatitis [11]. The incidence may be even higher than those reported in various regions of the country as often hepatitis is only diagnosed after clinical suspicion. The delay in diagnosis may con- tribute to a poor prognosis, with the presence of complications such as liver cirrhosis, hepatocellular carcinoma cell and even death.
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Some Morphological Aspects of Cylicocyclus brevicapsulatus (Nematoda: Cyathostominae) Parasite of Horse

Some Morphological Aspects of Cylicocyclus brevicapsulatus (Nematoda: Cyathostominae) Parasite of Horse

This paper describes some morphological aspects of Cylicocyclus brevicapsulatus (Ihle, 1920) (Nematoda: Cyathostominae) from Equus caballus in Brazil. The worms were studied using an optical microscope (measurements and illustrations) and a scanning electron microscope for a more detailed examination of the external morphology. The buccal capsule is very short, with a very thin wall, and the dorsal gutter is absent. Other morphological aspects are described including measurement of the spicules and gubernaculum.

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Development and some histochemical aspects of foliar glandular trichomes of Stevia rebaudiana (Bert.) Bert. - Asteraceae

Development and some histochemical aspects of foliar glandular trichomes of Stevia rebaudiana (Bert.) Bert. - Asteraceae

ABSTRACT - (Development and some histochemical aspects of foliar glandular trichomes of Stevia rebaudiana (Bert.) Bert. - Asteraceae). The ten-celled biseriate glandular trichome of Stevia rebaudiana (Bert.) Bert.-Asteraceae, found on both leaf surfaces, originates from a single protruding, protodermal cell undergoing an anticlinal division. A subsequent series of periclinal divisions, occurring in acropetal sequence, leads to the formation of the trichome, composed of five pairs of cells, one pair of basal cells, another of stalk cells and three pairs of secretory head cells. Developing, still two-celled glandular trichomes already occur on leaf primordia of the second pair (these primordia measuring, in some cases, ca. 0.30 mm in length), and most of the glandular trichomes are at the mature phase on very young, expanding leaves, for example on those of the sixth pair. The secretory material released by the head cells is stored in the trichome cavity (subcuticular space). Basic histochemical tests reveal that such material is lipophilic (mainly) and hydrophilic in nature.
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Generating the algebraic theory of C(X): the case of partially ordered  compact spaces

Generating the algebraic theory of C(X): the case of partially ordered compact spaces

This work is financed by the ERDF – European Regional Development Fund through the Operational Programme for Competitiveness and Internationalisation – COMPETE 2020 Pro- gramme and by National Funds through the Portuguese funding agency, FCT – Fundação para a Ciência e a Tecnologia within project POCI-01-0145-FEDER-016692. We also gratefully ac- knowledge partial financial assistance by Portuguese funds through CIDMA (Center for Research and Development in Mathematics and Applications), and the Portuguese Foundation for Sci- ence and Technology (“FCT – Fundação para a Ciência e a Tecnologia”), within the project UID/MAT/04106/2013. Finally, Renato Neves and Pedro Nora are supported by FCT grants SFRH/BD/52234/2013 and SFRH/BD/95757/2013, respectively.
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