26th Annual Computational Neuroscience Meeting (CNS*2017): Part 3 - Meeting Abstracts - Antwerp, Belgium. 15–20 July 2017

This work was produced as part of the activities of FAPESP Research,\ud Disseminations and Innovation Center for Neuromathematics (grant\ud 2013/07699-0, S. Paulo Research Foundation). NLK is supported by a\ud FAPESP postdoctoral fellowship (grant 2016/03855-5). ACR is partially\ud supported by a CNPq fellowship (grant 306251/2014-0)

Paleoclimatological implications of fossil tortoise bones

Samples of Oligocene fossil tortoise bone, paleosols and coprolites were collected from the “Turtle-Oreodon Layer” and elevations throughout the Scenic Member of the Brule Formation., White River Group, Paleogene (Badlands National Park, South Dakota) and fossil tortoise shell from Little Egypt Local Fauna, Vieja Group, Paleogene (Trans-Pecos Texas). These bones were analyzed for δ18O and δ13C isotope values of bone phosphate. Data generated from these samples are compared with contemporaneous deepsea drilling core isotope stratigraphy. Changes throughout the marine stratigraphic sections demonstrate a pulse-like transition of wet/dry seasonality with an increased aridity up section related to Paleogene glaciation of Antarctica. Climatic effects are mirrored lithologically by an up section sequence consistent with the drying climate (alternating coarse/fine sedimentation) of the late early Oligocene Scenic Member of the Brule Formation, White River Group. Coarse sediments of the Scenic Member replaced by finer grained, more chemically mature loess deposits of the Poleslide Member indicate a transition from a more moist climate This is accompanied faunally by replacement of large pulmonate gastropods by small pupoid gastropods and the divergence of Oligopherus and Stylemys from Hadrianus . Oligocene (Rupelian and Orellan {NALMA}) temperature fluctuations during the early Cenozoic Antarctic glaciation and paleoclimatology associated with global events is mirrored in the isotopic oxygen and carbon integral to fossil tortoise bone formation. Analyses of fossil materials and their associated isotopic results can be applied to high resolution nonmarine stratigraphic correlation. The isotopic information from the tortoise bone strongly outlines a step like climatic change which documents the faunal and floral transition in the Paleogene such as indicated by replacement of turtles by tortoises, browsing by grazing ungulates, subtropical by savannah vegetation, and a strong link to Milankovitch climatic cycles

Bigger Biceps Are Better: A Dyadic Analysis Between Male Friends

Building upon discourse completion task (DCT) research examining men’s responses to a fat talk prompt by a male friend, this study examined how men respond to a DCT with a muscle talk prompt. Adult men (N = 110) completed an online survey including measures of their body talk engagement and DCTs depicting male dyads of similar and different body types (e.g., normal-normal, normal-overweight, normal-muscular, normal-thin). For consistency, the respondent was depicted with a “normal” body type. The pattern of responses to the DCT dyads varied across the different speaker body types and differed compared to prior research using a fat prompt. Deflections and expansion requests were addressed more to the muscular speaker; whereas validations were given more toward normal and overweight speakers. Two sub-themes were added to the codebook. More research is needed to further understand what influences male friends’ body talk

Fingerprinting custom botnet protocol stacks

This paper explores the use of TCP fingerprints for identifying and blocking spammers. Evidence has shown that some bots use custom protocol stacks for tasks such as sending spam. If a receiver could effectively identify the bot TCP fingerprint, connection requests from spam bots could be dropped immediately, thus reducing the amount of spam received and processed by a mail server. Starting from a list of known spammers flagged by a commercial reputation list, we fingerprinted each spammer and found the roughly 90% have only a single known fingerprint typically associated with well known operating system stacks. For the spammers with multiple fingerprints, a particular combination of native/custom protocol stack fingerprints becomes very prominent. This allows us to extract the fingerprint of the custom stack and then use it to detect more bots that were not flagged by the commercial service. We applied our methodology to a trace captured at our regional ISP, and clearly detected bots belonging to the Srizbi botnet. ©2010 IEEE

Proanthocyanidin-enriched cranberry extract induces resilient bacterial community dynamics in a gnotobiotic mouse model

Cranberry consumption has numerous health benefits, with experimental reports showing its anti-inflammatory and anti-tumor properties. Importantly, microbiome research has demonstrated that the gastrointestinal bacterial community modulates host immunity, raising the question of whether the cranberry-derived effect may be related to its ability to modulate the microbiome. Only a few studies have investigated the effect of cranberry products on the microbiome to date. Especially because cranberries are rich in dietary fibers, the extent of microbiome modulation by polyphenols, particularly proanthocyanidins (PACs), remains to be shown. Since previous work has only focused on long-term effects of cranberry extracts, in this study we investigated the effect of a water-soluble, PAC-rich cranberry juice extract (CJE) on the short-term dynamics of a human-derived bacterial community in a gnotobiotic mouse model. CJE characterization revealed a high enrichment in PACs (57%), the highest ever utilized in a microbiome study. In a 37-day experiment with a ten-day CJE intervention and 14-day recovery phase, we profiled the microbiota via 16S rRNA sequencing and applied diverse time-series analytics methods to identify individual bacterial responses. We show that daily administration of CJE induces distinct dynamic patterns in bacterial abundances during and after treatment, before recovering resiliently to pre-treatment levels. Specifically, we observed an increase of Akkermansia muciniphila and Clostridium hiranonis at the expense of Bacteroides ovatus after the offset of the selection pressure imposed by the PAC-rich CJE. This demonstrates that termination of an intervention with a cranberry product can induce changes of a magnitude as high as the intervention itself

c-di-AMP signaling is required for bile salt resistance, osmotolerance, and long-term host colonization by Clostridioides difficile

International audienceTo colonize the host and cause disease, the human enteropathogen Clostridioides difficile must sense, respond, and adapt to the harsh environment of the gastrointestinal tract. We showed that the production and degradation of cyclic diadenosine monophosphate (c-di-AMP) were necessary during different phases of C. difficile growth, environmental adaptation, and infection. The production of this nucleotide second messenger was essential for growth because it controlled the uptake of potassium and also contributed to biofilm formation and cell wall homeostasis, whereas its degradation was required for osmotolerance and resistance to detergents and bile salts. The c-di-AMP binding transcription factor BusR repressed the expression of genes encoding the compatible solute transporter BusAA-AB. Compared with the parental strain, a mutant lacking BusR was more resistant to hyperosmotic and bile salt stresses, whereas a mutant lacking BusAA was more susceptible. A short exposure of C. difficile cells to bile salts decreased intracellular c-di-AMP concentrations, suggesting that changes in membrane properties induce alterations in the intracellular c-di-AMP concentration. A C. difficile strain that could not degrade c-di-AMP failed to persist in a mouse gut colonization model as long as the wild-type strain did. Thus, the production and degradation of c-di-AMP in C. difficile have pleiotropic effects, including the control of osmolyte uptake to confer osmotolerance and bile salt resistance, and its degradation is important for host colonization

Zebrafish Paralogs brd2a and brd2b Are Needed for Proper Circulatory, Excretory and Central Nervous System Formation and Act as Genetic Antagonists during Development

Brd2 belongs to the BET family of epigenetic transcriptional co-regulators that act as adaptor-scaffolds for the assembly of chromatin-modifying complexes and other factors at target gene promoters. Brd2 is a protooncogene and candidate gene for juvenile myoclonic epilepsy in humans, a homeobox gene regulator in Drosophila, and a maternal-zygotic factor and cell death modulator that is necessary for normal development of the vertebrate central nervous system (CNS). As two copies of Brd2 exist in zebrafish, we use antisense morpholino knockdown to probe the role of paralog Brd2b, as a comparative study to Brd2a, the ortholog of human Brd2. A deficiency in either paralog results in excess cell death and dysmorphology of the CNS, whereas only Brd2b deficiency leads to loss of circulation and occlusion of the pronephric duct. Co-knockdown of both paralogs suppresses single morphant defects, while co-injection of morpholinos with paralogous RNA enhances them, suggesting novel genetic interaction with functional antagonism. Brd2 diversification includes paralog-specific RNA variants, a distinct localization of maternal factors, and shared and unique spatiotemporal expression, providing unique insight into the evolution and potential functions of this gene