One-year survey of a single Micronesian reef reveals extraordinarily rich diversity of Symbiodinium types in soritid foraminifera

Recent molecular studies of symbiotic dinoflagellates (genus Symbiodinium) from a wide array of invertebrate hosts have revealed exceptional fine-scale symbiont diversity whose distribution among hosts, regions and environments exhibits significant biogeographic, ecological and evolutionary patterns. Here, similar molecular approaches using the internal transcribed spacer-2 (ITS-2) region were applied to investigate cryptic diversity in Symbiodinium inhabiting soritid foraminifera. Approximately 1,000 soritid specimens were collected and examined during a 12-month period over a 40m depth gradient from a single reef in Guam, Micronesia. Out of 61 ITS-2 types distinguished, 46 were novel. Most types found are specific for soritid hosts, except for three types (C1, C15 and C19) that are common in metazoan hosts. The distribution of these symbionts was compared with the phylotype of their foraminiferal hosts, based on soritid small subunit ribosomal DNA sequences, and three new phylotypes of soritid hosts were identified based on these sequences. Phylogenetic analyses of 645 host-symbiont pairings revealed that most Symbiodinium types associated specifically with a particular foraminiferal host genus or species, and that the genetic diversity of these symbiont types was positively correlated with the genetic diversity found within each of the three host genera. Compared to previous molecular studies of Symbiodinium from other locations worldwide, the diversity reported here is exceptional and suggests that Micronesian coral reefs are home to a remarkably large Symbiodinium assemblag

From a Static Impossibility to an Adaptive Lower Bound: the Complexity of Early Deciding Set Agreement

In the year 2007 a reform was established that allowed private citizens in Sweden to make tax deductions on companies providing services pertaining to the household (called RUT-deduction). The year later another reform was introduced granting citizens additional tax deductions but this time concerning household renovation, reconstruction and extensive construction (called ROT-deduction). These tax deductions resulted in higher employment and more jobs being executed legally. The purpose of this paper is to examine and analyze what kind of effects these types of tax deductions would have on workers’ real wages and to look at to what extent these effects differ within a female dominated occupation and a male dominated occupation, from a gender perspective. The two professions that are chosen to be researched in this paper are the cleaning and painting professions. Furthermore, the purpose with this study is to examine whether this effect differs within the two separate professions. The study is executed with the use of econometric models, point estimation, economic theory and empirical studies. The result indicates that the RUT-deduction has the biggest positive impact on cleaners’ real wages. This paper shows that one underlying reason to this outcome could be that the cleaning service is a more price sensitive service and that the RUT-deduction might therefore have generated an excess in demand for that service. Nonetheless, to establish an equilibrium in the labor market the wages are required to rise in order to attract more cleaners to enter the certain market. However, this paper is unable to eliminate the possible theory of there being a general wage increase among workers in the private sector. In addition, this study is comprised of an inadequate amount of observations which impedes any reliable conclusions from being made based on evidence

Functional Imaging of Decision Conflict

Decision conflict occurs when people feel uncertain as to which option to choose from a set of similarly attractive (or unattractive) options, with many studies demonstrating that this conflict can lead to suboptimal decision making. In this article, we investigate the neurobiological underpinnings of decision conflict, in particular, the involvement of the anterior cingulate cortex (ACC). Previous studies have implicated the ACC in conflict monitoring during perceptual tasks, but there is considerable controversy as to whether the ACC actually indexes conflict related to choice, or merely conflict related to selection of competing motor responses. In a functional magnetic resonance imaging study, we dissociate the decision and response phases of a decision task, and show that the ACC does indeed index conflict at the decision stage. Furthermore, we sho that it does so for a complex decision task, one that requires the integration of beliefs and preferences and not just perceptual judgments

Analyse des déhydrines chez le champignon phytopathogène Alternaria brassicicola

National audienc

The Arabidopsis thaliana-Alternaria brassicicola pathosystem: A model interaction for investigating seed transmission of necrotrophic fungi

Seed transmission constitutes a major component of the parasitic cycle for several fungal pathogens. However, very little is known concerning fungal or plant genetic factors that impact seed transmission and mechanisms underlying this key biological trait have yet to be clarified. Such lack of available data could be probably explained by the absence of suitable model pathosystem to study plant-fungus interactions during the plant reproductive phase

Generalist dinoflagellate endosymbionts and host genotype diversity detected from mesophotic (67-100 m depths) coral Leptoseris

<p>Abstract</p> <p>Background</p> <p>Mesophotic corals (light-dependent corals in the deepest half of the photic zone at depths of 30 - 150 m) provide a unique opportunity to study the limits of the interactions between corals and endosymbiotic dinoflagellates in the genus <it>Symbiodinium</it>. We sampled <it>Leptoseris </it>spp. in Hawaii via manned submersibles across a depth range of 67 - 100 m. Both the host and <it>Symbiodinium </it>communities were genotyped, using a non-coding region of the mitochondrial ND5 intron (NAD5) and the nuclear ribosomal internal transcribed spacer region 2 (ITS2), respectively.</p> <p>Results</p> <p>Coral colonies harbored endosymbiotic communities dominated by previously identified shallow water <it>Symbiodinium </it>ITS2 types (C1_ AF333515, C1c_ AY239364, C27_ AY239379, and C1b_ AY239363) and exhibited genetic variability at mitochondrial NAD5.</p> <p>Conclusion</p> <p>This is one of the first studies to examine genetic diversity in corals and their endosymbiotic dinoflagellates sampled at the limits of the depth and light gradients for hermatypic corals. The results reveal that these corals associate with generalist endosymbiont types commonly found in shallow water corals and implies that the composition of the <it>Symbiodinium </it>community (based on ITS2) alone is not responsible for the dominance and broad depth distribution of <it>Leptoseris </it>spp. The level of genetic diversity detected in the coral NAD5 suggests that there is undescribed taxonomic diversity in the genus <it>Leptoseris </it>from Hawaii.</p