Instances Of Association Research Articles

Reviewing ecological implications of mycorrhizal fungal interactions in the Brassicaceae

Mycorrhizal associations are plant-fungal mutualisms that are fairly ubiquitous and likely evolved multiple times in phylogenic history; however, some plant families have consistently been identified as non-mycorrhizal, including the Brassicaceae. In this paper, we reviewed the literature and DNA databases for potential mechanisms that preclude mycorrhizal symbioses in the Brassicaceae and for exceptions to the general observation of non-mycorrhizal status within this plant family. In instances of association between members of the Brassicaceae and arbuscular mycorrhizal fungi we posed hypotheses for why these interactions occur in the species and sites observed. Instances of inconsistent association with mycorrhizal fungi were attributed to inter- and intraspecific variations in plant biology, disagreements in vernacular, methodology contradicting historical mycorrhizal surveys, and association being a facultative, variable trait that is determined by species-site interactions. We propose further research on a) the extent of mycorrhizal association in the Brassicaceae, b) the molecular mechanisms dictating association, and c) whether Brassicaceae-mycorrhizal fungal interactions result in nutrient transfer, and their particular roles in the family’s distribution across heterogeneous and harsh environments.

The Object of Allegory (A Polemic)

This article reads together Baudelaire’s poem “Le Cygne” and sections from Freud’s Mourning and Melancholia in order to argue that a pathology of melancholic allegory and the norm of grievable object loss coexist in an endless and nondialectical struggle that is to be affirmed. The allegory of melancholia translates the loss of the object into the defective principle on which—because of our structural disanalogy, because of the conflict between institution and principle at the heart of the catastrophe of representative democracy today—subjects stand forth as distinctly grievable-ungrievable objects, and on this defective concept may found ephemeral, transparent, and formal administrative modes, agencies, and instances of association. These are called, in the article, globally weak republican institutions.

Éruption polymorphe de la grossesse associée à une hémophilie acquise A

Acquired haemophilia A (AHA) is a rare and serious disease, and instances of association with skin diseases have been described. We report a case of postpartum AHA associated with atypical polymorphic eruption of pregnancy (PEP). Following delivery of her second child, a 27-year-old woman developed a generalised pruritic erythematous papular and vesicular rash in plaques. The diagnosis of pemphigoid gestationis was ruled out on the basis of negative immunopathology results and a diagnosis of PEP was made. Lengthening of activated cephalin time was observed, without correction by addition of control plasma, and prothrombin time was normal. AHA was confirmed by the very low levels of factor VIII and the presence of antifactor VIII antibody. The patient was given intravenous activated recombinant factor VII for epistaxis and gingival bleeding, followed by an infusion of polyvalent immunoglobulins and systemic corticosteroids. Both diseases regressed within a few weeks. This case is original in terms of the atypical presentation of AHA associated with severe PEP. AHA was associated with the presence of antifactor VIII Ab. Although the disease generally occurs alone, it has already been reported during pregnancy and the postpartum period, and in association with various forms of dermatosis, including bullous pemphigoid, although to our knowledge, never in association with PEP or pemphigoid gestationis. However, neither the underlying mechanisms of this association of PEP and AHA, which was probably not a chance occurrence, nor the risks of relapse of these conditions during subsequent pregnancies have been elucidated.

Association of Genetic Risk Variants With Expression of Proximal Genes Identifies Novel Susceptibility Genes for Cardiovascular Disease

Population-based genome-wide association studies have identified several single nucleotide polymorphisms (SNPs) associated with cardiovascular disease or its risk factors. Genes in close proximity to these risk-SNPs are often thought to be pathogenetically important based on their location alone. However, the actual connections between SNPs and disease mechanisms remain largely unknown. To identify novel susceptibility genes, we investigated how 166 SNPs previously found to be associated with increased cardiovascular risk and/or predisposing metabolic traits relate to the expression of nearby genes. Gene expression in 577 samples of aorta, liver, mammary artery, and carotid atherosclerotic plaque was measured using expression arrays. For 47 SNPs, the expression levels of proximal genes (located within 200 kb) were affected (P<0.005). More than 20 of these genes had not previously been identified as candidate genes for cardiovascular or related metabolic traits. SNP-associated gene effects were tissue-specific and the tissue specificity was phenotype-dependent. This study demonstrates several instances of association between risk-SNPs and genes immediately adjacent to them. It also demonstrates instances in which the associated gene is not the immediately proximal and obvious candidate gene for disease. This shows the necessity of careful studies of genetic marker data as a first step toward application of genome-wide association studies findings in a clinical setting.

New records of Amphipoda Hyperiidea in associations with gelatinous zooplankton

Associations between Amphipoda Hyperiidea specimens and gelatinous zooplankton such as cnidarians, ctenophores or salps are known in the literature. It is well established that many hyperiids are intimately associated with gelatinous zooplankton during part or all of their life-cycles, and that the associations could be of commensal or of parasitic nature, sometimes very highly species-specific. Although conventional net sampling usually does not preserve evidence of these associations, 12 instances of association (I.A.) were found in nine of the 49 samples collected during the 'FINEP XI Cruise', carried out on the Southeast coast of Brazil (23–28 °S), in January 1980. Lestrigonus bengalensisGiles, 1887 (11 specimens) and Simorhynchotus antennarius(Claus, 1871) (one specimen) were found inside salps and siphonophores. The study of the nature of these associations is essential to the understanding of the evolution of the group.

Overgeneralizations of number inflections in the learning of written French: The case of noun and verb

The present article reports a study of overgeneralizations occurring in the learning of written French morphology in which the markers of plurality for nouns (‐s) and verbs (‐nt) are mostly not audible. Because of this inaudibility, many nouns and verbs that are pronounced alike are spelled differently. French writers are thus confronted with interference in such cases: two (‐s vs. ‐nt) graphemic configurations are possible for the same phonological configuration, which sometimes leads to errors in adults. The experiment shows that, at a certain point during their learning of written morphology, children make the same type of error: they (over) generalize the number marker for nouns (‐s) to verbs and the number marker for verbs (‐nt) to nouns, before achieving complete mastery of plural morphology. Moreover, children would store and use instances of associations between stems and morphemes when an item can, depending on the context, be either a noun or a verb. In this case, the occurrence frequencies of instances would determine the probability and the intensity of plural morpheme activation, leading to the appearance of homophone effects which have already been described in adults: nouns frequently encountered as verbs are often inflected with (‐nt), whereas only verbs frequently used as nouns are inflected with (‐s). These results are discussed within the framework of an activation model involving both rules and associations

Why don’tSaimiri oerstedii andCebus capucinus form mixed-species groups?

The instances of association with Cebus capucinustroops were monitored for 11 months as part of a field study of Saimiri oerstediiin a tropical wet forest in Costa Rica, Parque Nacional Corcovado. Contrary to the usual situation in South America, where S. sciureusforms persistent mixed-species groups with Cebus apella,in Corcovado S. oerstediirarely associated with Cebus capucinus;the frequencies were consistent with those expected from random association. Depending on the season, the S. oerstediitroop spent between 2.3 and 11.8% of its time in the vicinity of a Cebus capucinustroop. Most associations appeared to be chance meetings of short duration. When the two species did associate for an extended period, it was Cebus capucinus,and not S. oerstedii,that appeared to maintain the association, possibly in order to benefit from the antipredator behavior of S. oerstedii.There was no evidence that either species benefited from enhanced foraging efficiency when in association.

A mathematical data/knowledge model: The formal association inference model FAIM

Data base (DB) technology is a large field, comprising DB design methods, DB theory, DB models, DB management, and DB applications. In recent years, formally defined DB models have become an important topic. In knowledge representation, being the Artificial Intelligence area most closely related to DB research, the general trend moves towards the standard description of models by predicate logic. For DB design, an architecture on 3 abstraction levels is a widely accepted standard. It distinguishes between the conceptual level, the internal level, and the external level. On the conceptual level the problem relevant aspects are exclusively considered, whereas on the internal level the physical aspects (implementation details), and on the external level specific applications are treated. Each level has its respective schemas. In this paper we focus on already designed FAIM conceptual schemas (a design method is available): A mathematical model is developed for them. Each FAIM conceptual schema consists of association types (FAIM) with action types thereon (insert/retrieve/modify/delete) and inference typēs̄ (FAIM), all of which are formally defined (FAIM) by first order logic with equality. Associations, actions, and inferences are instances of association, action, and inference types. Associations are modelled relations among modelled living beings, things (so-called individuals), or abstract concepts (so-called designators). An object (individual or designator) must be modelled as an individual if either its name may be subject to change, or if its name is a compound name. Objects play so-called roles within associations. Actions are modelled events, inferences modelled rules. The use of predicate logic leads to particularly exact, unambiguous, and expressive definitions. Nevertheless only few models have been rigorously defined for conceptual schemas. Within the scope of further developments FAIM is going to be a model of knowledge representation schemas.

Association of the pedunculate barnacle, Conchoderma virgatum (Spengler, 1790), with pandarid copepods (Siphonostomatoida: Pandaridae)

Four separate instances of association between the pedunculate barnacle, Conchoderma virgatum (Spengler, 1790), and ectoparasitic copepods are described. The copepods were all adult females of the family Pandaridae: Dinemoura latifolia (Steenstrup &amp;Lütken, 1861) (two instances), Pandarus satyrus Dana, 1852, and Perissopus dentatus Steenstrup &amp;Lütken, 1861. It is speculated that the sessile nature and formidable grasping power of adult female pandarids probably facilitated the barnacle–cope pod associations, as highly motile and (or) less powerfully attaching copepod species would likely be torn from their hosts by the increased hydrodynamic drag placed upon them in carrying C. virgatum. Because the copepods appeared neither to derive benefit from nor to be harmed by their barnacle associates, it is felt that these symbiotic associations are best regarded as instances of phoresy.

Prokaryotic algae associated with Australian proterozoic stromatolites.

Five instances of association between distinctive stromatolites and blue-green algal nannofossils are recorded from a 100-m sequence of carbonate rocks about 1.6 x 10(9) years old, along the south side of Paradise Creek, northwestern Queensland, Australia. No eukaryotes were identified in any of these systematically limited assemblages, although they are known from rocks as old as 1.3 x 10(9) years in eastern California. Thus, eukaryotes may not have appeared until after 1.6 x 10(9) years ago (but before 1.3 x 10(9) years ago). The associations observed would also be consistent with (but do not prove) a biotic influence on stromatolite morphology. As is usual among prePaleozoic forms described, the morphology of the nannofossils is very similar to living forms, displaying marked evolutionary conservatism. Primary orientation of stromatolitic laminae and columns is not invariably convex upward, as conventionally believed, but convex away from and parallel to the initial point or surface of attachment, which may be horizontal or even downward beneath overhangs.