Primate drum kit: A system for studying acoustic pattern production by non-human primates using acceleration and strain sensors

The possibility of achieving experimentally controlled, non-vocal acoustic production in non-human primates is a key step to enable the testing of a number of hypotheses on primate behavior and cognition. However, no device or solution is currently available, with the use of sensors in non-human animals being almost exclusively devoted to applications in food industry and animal surveillance. Specifically, no device exists which simultaneously allows: (i) spontaneous production of sound or music by non-human animals via object manipulation, (ii) systematical recording of data sensed from these movements, (iii) the possibility to alter the acoustic feedback properties of the object using remote control. We present two prototypes we developed for application with chimpanzees (Pan troglodytes) which, while fulfilling the aforementioned requirements, allow to arbitrarily associate sounds to physical object movements. The prototypes differ in sensing technology, costs, intended use and construction requirements. One prototype uses four piezoelectric elements embedded between layers of Plexiglas and foam. Strain data is sent to a computer running Python through an Arduino board. A second prototype consists in a modified Wii Remote contained in a gum toy. Acceleration data is sent via Bluetooth to a computer running Max/MSP. We successfully pilot tested the first device with a group of chimpanzees. We foresee using these devices for a range of cognitive experiments. © 2013 by the authors; licensee MDPI, Basel, Switzerland

Impact of the multiscale viscoelasticity of quasi-2D self-assembled protein networks on stem cell expansion at liquid interfaces

Although not typically thought to sustain cell adhesion and expansion, liquid substrates have recently been shown to support such phenotypes, providing protein nanosheets could be assembled at corresponding liquid-liquid interfaces. However, the precise mechanical properties required from such quasi-2D nanoassemblies and how these correlate with molecular structure and nanoscale architecture has remained unclear. In this report, we screen a broad range of surfactants, proteins, oils and cell types and correlate interfacial mechanical properties with stem cell expansion. Correlations suggest an impact of interfacial viscoelasticity on the regulation of such behaviour. We combine interfacial rheology and magnetic tweezer-based interfacial microrheology to characterise the viscoelastic profile of protein nanosheets assembled at liquid-liquid interfaces. Based on neutron reflectometry and transmission electron microscopy data, we propose that the amorphous nanoarchitecture of quasi-2D protein nanosheets controls their multi-scale viscoelasticity which, in turn, correlates with cell expansion. This understanding paves the way for the rational design of protein nanosheets for microdroplet and bioemulsion-based stem cell manufacturing and screening platforms

Características clínicas y evolución de la infección por SARS-CoV-2 en pacientes con lupus eritematoso sistémico en Argentina: datos del registro nacional SAR-COVID

Introducción: el lupus eritematoso sistémico (LES) es una enfermedad sistémica que se ha asociado a mayor severidad con la infección por SARS-CoV-2. Particularmente la alta actividad de la enfermedad y algunos inmunosupresores se han vinculado a peores desenlaces. Objetivos: describir las características por SARS-CoV-2 en pacientes con LES en Argentina del registro SAR-COVID y establecer los factores asociados a peor desenlace de la misma. Materiales y métodos: estudio observacional. Se incluyeron pacientes con diagnóstico de LES con infección confirmada por SARS-CoV-2 (RT-PCR y/o serología positiva) del registro SAR-COVID. Los datos se recolectaron desde agosto de 2020 hasta marzo de 2022. El desenlace de la infección se midió mediante la escala ordinal de la Organización Mundial de la Salud (EO-OMS). Se definió COVID-19 severo con un valor EO-OMS ≥5. Análisis descriptivo, test T de Student, U de Mann Whitney U, ANOVA, chi2 y Fisher. Regresión logística múltiple. Resultados: se incluyeron 399 pacientes, el 93% de sexo femenino, con una edad media de 40,9 años (DE 12,2). El 39,6% tenía al menos una comorbilidad. Al momento de la infección, el 54,9% recibía glucocorticoides, el 30,8% inmunosupresores y el 3,3% agentes biológicos. La infección por SARS-CoV-2 fue leve en la mayoría de los casos, mientras que un 4,6% tuvo curso severo y/o falleció. Estos últimos presentaban comorbilidades, usaban glucocorticoides y tenían síndrome antifosfolípido (SAF) con mayor frecuencia y mayor actividad de la enfermedad al momento de la infección. En el análisis multivariado, la hipertensión arterial, el diagnóstico de SAF y el uso de glucocorticoides se asociaron a hospitalización severa y/o muerte por COVID-19 (EO-OMS ≥5). Conclusiones: en esta cohorte de pacientes con LES con infección por SARS-CoV-2 confirmada, la mayoría cursó de manera sintomática, un 22,1% fue hospitalizado y un 5% requirió ventilación mecánica. La mortalidad fue cercana al 3%. El diagnóstico de SAF, tener hipertensión arterial y el uso de glucocorticoides se asociaron significativamente con COVID-19 severo

Cost-effective rapid prototyping and assembly of poly(methyl methacrylate) microfluidic devices.

The difficulty in translating conventional microfluidics from laboratory prototypes to commercial products has shifted research efforts towards thermoplastic materials for their higher translational potential and amenability to industrial manufacturing. Here, we present an accessible method to fabricate and assemble polymethyl methacrylate (PMMA) microfluidic devices in a “mask-less” and cost-effective manner that can be applied to manufacture a wide range of designs due to its versatility. Laser micromachining offers high flexibility in channel dimensions and morphology by controlling the laser properties, while our two-step surface treatment based on exposure to acetone vapour and low-temperature annealing enables improvement of the surface quality without deformation of the device. Finally, we demonstrate a capillarity-driven adhesive delivery bonding method that can produce an effective seal between PMMA devices and a variety of substrates, including glass, silicon and LiNbO3. We illustrate the potential of this technique with two microfluidic devices, an H-filter and a droplet generator. The technique proposed here offers a low entry barrier for the rapid prototyping of thermoplastic microfluidics, enabling iterative design for laboratories without access to conventional microfabrication equipment

Roots into functional nodes: Exploring locality and semi-lexicality

We explore certain predictions of the theory first presented in Acedo-Matellán and Real-Puigdollers (2014), whereby roots correspond to (lately inserted) Vocabulary Items that phonologically and semantically interpret functional nodes. First, we deal with categorizers (a, n, v), a prominent locus for the insertion of roots. Roots such as cat or up are Vocabulary Items that have no context of insertion and are insertable into any categorizer, accounting for the categorial variability of simple words. Derivational affixes like -ation or -al also correspond to roots inserted into little head categorizers (n and a, respectively, in this case), but their Vocabulary Items have a context of insertion accounting for their categorial rigidity and their c-selection properties. The exploration proposed here focuses, first, on the locality properties of morphemic interactions at the semantic interface, namely, allosemic interactions. We show that our approach makes felicitous predictions seemingly unavailable to those other localist approaches in which roots are distinct nodes in the syntax. Second, we show that the phenomenon of semi-lexicality, as illustrated by classifiers, can be successfully modeled, in our framework, as the insertion of roots into inflectional nodes

G Protein-Coupled Estrogen Receptor Regulates Actin Cytoskeleton Dynamics to Impair Cell Polarization

Mechanical forces regulate cell functions through multiple pathways. G protein-coupled estrogen receptor (GPER) is a seven-transmembrane receptor that is ubiquitously expressed across tissues and mediates the acute cellular response to estrogens. Here, we demonstrate an unidentified role of GPER as a cellular mechanoregulator. G protein-coupled estrogen receptor signaling controls the assembly of stress fibers, the dynamics of the associated focal adhesions, and cell polarization via RhoA GTPase (RhoA). G protein-coupled estrogen receptor activation inhibits F-actin polymerization and subsequently triggers a negative feedback that transcriptionally suppresses the expression of monomeric G-actin. Given the broad expression of GPER and the range of cytoskeletal changes modulated by this receptor, our findings position GPER as a key player in mechanotransduction

Substrate stiffness-driven membrane tension modulates vesicular trafficking via caveolin-1.

Liver fibrosis, a condition characterized by extensive deposition and cross-linking of extracellular matrix (ECM) proteins, is idiosyncratic in cases of chronic liver injury. The dysregulation of ECM remodeling by hepatic stellate cells (HSCs), the main mediators of fibrosis, results in an elevated ECM stiffness that drives the development of chronic liver disease such as cirrhosis and hepatocellular carcinoma. Tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) is a key element in the regulation of ECM remodeling, which modulates the degradation and turnover of ECM components. We have previously reported that a rigid, fibrotic-like substrate can impact TIMP-1 expression at the protein level in HSCs without altering its mRNA expression. While HSCs are known to be highly susceptible to mechanical stimuli, the mechanisms through which mechanical cues regulate TIMP-1 at the post-translational level remain unclear. Here, we show a mechanism of regulation of plasma membrane tension by matrix stiffness. We found that this effect is orchestrated by the β1 integrin/RhoA axis and results in elevated exocytosis and secretion of TIMP-1 in a caveolin-1- and dynamin-2-dependent manner. We then show that TIMP-1 and caveolin-1 expression increases in cirrhosis and hepatocellular carcinoma. These conditions are associated with fibrosis, and this effect can be recapitulated in 3D fibrosis models consisting of hepatic stellate cells encapsulated in a self-assembling polypeptide hydrogel. This work positions stiffness-dependent membrane tension as a key regulator of enzyme secretion and function and a potential target for therapeutic strategies that aim at modulating ECM remodeling in chronic liver disease