230 research outputs found

    Can vocal conditioning trigger a semiotic ratchet in marmosets?

    Get PDF
    The complexity of human communication has often been taken as evidence that our language reflects a true evolutionary leap, bearing little resemblance to any other animal communication system. The putative uniqueness of the human language poses serious evolutionary and ethological challenges to a rational explanation of human communication. Here we review ethological, anatomical, molecular and computational results across several species to set boundaries for these challenges. Results from animal behavior, cognitive psychology, neurobiology, and semiotics indicate that human language shares multiple features with other primate communication systems, such as specialized brain circuits for sensorimotor processing, the capability for indexical (pointing) and symbolic (referential) signaling, the importance of shared intentionality for associative learning, affective conditioning and parental scaffolding of vocal production. The most substantial differences lie in the higher human capacity for symbolic compositionality, fast vertical transmission of new symbols across generations, and irreversible accumulation of novel adaptive behaviors (cultural ratchet). We hypothesize that increasingly-complex vocal conditioning of an appropriate animal model may be sufficient to trigger a semiotic ratchet, evidenced by progressive sign complexification, as spontaneous contact calls become indexes, then symbols and finally arguments (strings of symbols). To test this hypothesis, we outline a series of conditioning experiments in the common marmoset (Callithrix jacchus). The experiments are designed to probe the limits of vocal communication in a prosocial, highly vocal primate 35 million years far from the human lineage, so as to shed light on the mechanisms of semiotic complexification and cultural transmission, and serve as a naturalistic behavioral setting for the investigation of language disorders

    Heisenberg models and Schur–Weyl duality

    Get PDF
    We present a detailed analysis of certain quantum spin systems with inhomogeneous (non-random) mean-field interactions. Examples include, but are not limited to, the interchange- and spin singlet projection interactions on complete bipartite graphs. Using two instances of the representation theoretic framework of Schur–Weyl duality, we can explicitly compute the free energy and other thermodynamic limits in the models we consider. This allows us to describe the phase transition, the ground-state phase diagram, and the expected structure of extremal states

    A preliminary assessment of water partitioning and ecohydrological coupling in northern headwaters using stable isotopes and conceptual runoff models

    Get PDF
    Funded by European Research Council ERC. Grant Number: GA 335910 VEWA Swedish Science Foundation (SITES) Future Forest Formas (ForWater) SKB the Kempe foundation Environment Canada the Garfield Weston Foundation the Natural Sciences and Engineering Research Council of Canada (NSERC) the Northwest Territories Cumulative Impacts Monitoring ProgramPeer reviewedPublisher PD

    Amino Acid Accumulation Limits the Overexpression of Proteins in Lactococcus lactis

    Get PDF
    Background: Understanding the biogenesis pathways for the functional expression of recombinant proteins, in particular membrane proteins and complex multidomain assemblies, is a fundamental issue in cell biology and of high importance for future progress in structural genomics. In this study, we employed a proteomic approach to understand the difference in expression levels for various multidomain membrane proteins in L. lactis cells grown in complex and synthetic media. Methodology/Principal Findings: The proteomic profiles of cells growing in media in which the proteins were expressed to high or low levels suggested a limitation in the availability of branched-chain amino acids, more specifically a too limited capacity to accumulate these nutrients. By supplying the cells with an alternative path for accumulation of Ile, Leu and/or Val, i.e., a medium supplement of the appropriate dipeptides, or by engineering the transport capacity for branched-chain amino acids, the expression levels could be increased several fold. Conclusions: We show that the availability of branched chain amino acids is a critical factor for the (over) expression of proteins in L. lactis. The forward engineering of cells for functional protein production required fine-tuning of co-expression of the branched chain amino acid transporter

    Stable isotopes of water reveal differences in plant – soil water relationships across northern environments

    Get PDF
    Funding Information: We thank the European Research Council ERC for funding (VeWa project GA 335910). Contributions from CS were supported by the Leverhulme Trust through the ISO-LAND project (RPG 2018 375). Support for MJK and JPM were provided by the US National Science Foundation (EAR0842367) and Boise State University. We thank Dr. Samantha Evans for technical support. Thanks to the Dorset Environmental Science Centre for provision of meteorological data. The work conducted in Krycklan was partly financed by SITES (VR) and the KAW Branch-Point project. We would like to acknowledge Dr. Nadine Shatilla for collection of the Wolf Creek samples and the Global Water Futures program for financial support. We also would like to sincerely thank Jeff McDonnell for his support throughout the VeWa project and all participants in the different VeWa workshops esp. Tanya Doody and Marco Maneta for their invaluable input into the discussions.Peer reviewedPublisher PD

    Identification of Damage Associated Molecular Patterns and Extracellular Matrix Proteins as Major Constituents of the Surface Proteome of Lung Implantable Silicone/Nitinol Devices

    Get PDF
    Lung implantable devices have been widely adopted as mechanical interventions for a wide variety of pulmonary pathologies. Despite successful initial treatment, long-term efficacy can often be impacted by fibrotic or granulation tissue formation at the implant sites. This study aimed to explore the lung-device interface by identifying the adhered proteome on lung devices explanted from patients with severe emphysema. In this study, scanning electron microscopy is used to visualize the adhesion of cells and proteins to silicone and nitinol surfaces of explanted endobronchial valves. By applying high-resolution mass-spectrometry, the surface proteome of eight explanted valves is characterized, identifying 263 unique protein species to be mutually adsorbed on the valves. This subset is subjected to gene enrichment analysis, matched with known databases and further validated using immunohistochemistry. Enrichment analyses reveal dominant clusters of functionally-related ontology terms associated with coagulation, pattern recognition receptor signaling, immune responses, cytoskeleton organization, cell adhesion and migration. Matching results show that extracellular matrix proteins and damage-associated molecular patterns are cardinal in the formation of the surface proteome. This is the first study investigating the composition of the adhered proteome on explanted lung devices, setting the groundwork for hypothesis generation and further exploration. STATEMENT OF SIGNIFICANCE: This is the first study investigating the composition of the adhered proteome on explanted lung devices. Lung implantable devices have been widely adopted as mechanical interventions for pulmonary pathologies. Despite successful initial treatment, long-term efficacy can often be impacted by fibrotic or granulation tissue formation around the implant sites. We identified the adhered proteome on explanted lung devices using several techniques. We identified 263 unique protein species to be mutually adsorbed on explanted lung devices. Pathway analyses revealed that these proteins are associated with coagulation, pattern recognition receptor signaling, immune responses, cytoskeleton organization, cell adhesion and migration. Furthermore, we identified that especially extracellular matrix proteins and damage-associated molecular patterns were cardinal in the formation of the surface proteome

    How to Approach Para-Aortic Lymph Node Metastases During Exploration for Suspected Periampullary Carcinoma:Resection or Bypass?

    Get PDF
    Background: Intraoperative para-aortic lymph node (PALN) sampling during surgical exploration in patients with suspected pancreatic head cancer remains controversial. Objective: The aim of this study was to assess the value of routine PALN sampling and the consequences of different treatment strategies on overall patient survival. Methods: A retrospective, multicenter cohort study was performed in patients who underwent surgical exploration for suspected pancreatic head cancer. In cohort A, the treatment strategy was to avoid pancreatoduodenectomy and to perform a double bypass procedure when PALN metastases were found during exploration. In cohort B, routinely harvested PALNs were not examined intraoperatively and pancreatoduodenectomy was performed regardless. PALNs were examined with the final resection specimen. Clinicopathological data, survival data and complication data were compared between study groups. Results: Median overall survival for patients with PALN metastases who underwent a double bypass procedure was 7.0 months (95% confidence interval [CI] 5.5–8.5), versus 11 months (95% CI 8.8–13) in the pancreatoduodenectomy group (p = 0.049). Patients with PALN metastases who underwent pancreatoduodenectomy had significantly increased postoperative morbidity compared with patients who underwent a double bypass procedure (p < 0.001). In multivariable analysis, severe comorbidity (ASA grade 2 or higher) was an independent predictor for decreased survival in patients with PALN involvement (hazard ratio 3.607, 95% CI 1.678–7.751; p = 0.001). Conclusion: In patients with PALN metastases, pancreatoduodenectomy was associated with significant survival benefit compared with a double bypass procedure, but with increased risk of complications. It is important to weigh the advantages of resection versus bypass against factors such as comorbidities and clinical performance when positive intraoperative PALNs are found

    The Critically Endangered western chimpanzee declines by 80%

    Get PDF
    African large mammals are under extreme pressure from unsustainable hunting and habitat loss. Certain traits make large mammals particularly vulnerable. These include late age at first reproduction, long inter-birth intervals, and low population density. Great apes are a prime example of such vulnerability, exhibiting all of these traits. Here we assess the rate of population change for the western chimpanzee, Pan troglodytes verus, over a 24-year period. As a proxy for change in abundance, we used transect nest count data from 20 different sites archived in the IUCN SSC A.P.E.S. database, representing 25,000 of the estimated remaining 35,000 western chimpanzees. For each of the 20 sites, datasets for 2 different years were available. We estimated site-specific and global population change using Generalized Linear Models. At 12 of these sites, we detected a significant negative trend. The estimated change in the subspecies abundance, as approximated by nest encounter rate, yielded a 6% annual decline and a total decline of 80.2% over the study period from 1990 to 2014. This also resulted in a reduced geographic range of 20% (657,600 vs. 524,100&thinsp;km2). Poverty, civil conflict, disease pandemics, agriculture, extractive industries, infrastructure development, and lack of law enforcement, are some of the many reasons for the magnitude of threat. Our status update triggered the uplisting of the western chimpanzee to &ldquo;Critically Endangered&rdquo; on the IUCN Red List. In 2017, IUCN will start updating the 2003 Action Plan for western chimpanzees and will provide a consensus blueprint for what is needed to save this subspecies. We make a plea for greater commitment to conservation in West Africa across sectors. Needed especially is more robust engagement by national governments, integration of conservation priorities into the private sector and development planning across the region and sustained financial support from donors.Additional co-authors: Emma Normand, Kathryn Shutt-Phillips, Alexander Tickle, Elleni Vendras, Adam Welsh, Erin G. Wessling, Christophe Boesc
    corecore