Bimodality in gene expression without feedback: From Gaussian white noise to log-normal coloured noise

Extrinsic noise-induced transitions to bimodal dynamics have been largely investigated in a variety of chemical, physical, and biological systems. In the standard approach in physical and chemical systems, the key properties that make these systems mathematically tractable are that the noise appears linearly in the dynamical equations, and it is assumed Gaussian and white. In biology, the Gaussian approximation has been successful in specific systems, but the relevant noise being usually non-Gaussian, non-white, and nonlinear poses serious limitations to its general applicability. Here we revisit the fundamental features of linear Gaussian noise, pinpoint its limitations, and review recent new approaches based on nonlinear bounded noises, which highlight novel mechanisms to account for transitions to bimodal behaviour. We do this by considering a simple but fundamental gene expression model, the repressed gene, which is characterized by linear and nonlinear dependencies on external parameters. We then review a general methodology introduced recently, so-called nonlinear noise filtering, which allows the investigation of linear, nonlinear, Gaussian and non-Gaussian noises. We also present a derivation of it, which highlights its dynamical origin. Testing the methodology on the repressed gene confirms that the emergence of noise-induced transitions appears to be strongly dependent on the type of noise adopted, and on the degree of nonlinearity present in the system.Comment: Review paper, 17 pages, 8 figure

Executive functions in insomnia disorder: a systematic review and exploratory meta-analysis

Background: Executive functions (EFs) are involved in the control of basic psychological processes such as attention and memory and also contribute to emotion regulation. Research on the presence of EFs impairments in insomnia yielded inconsistent results. Therefore, we performed a systematic review of the literature on three EFs: inhibitory control, working memory, and cognitive flexibility in adults with insomnia in order to investigate the presence and magnitude of insomnia-related EFs impairments. Methods: PubMed, Scopus, Medline, and PsycINFO were searched. Risk of bias assessment of included studies was performed by two independent researchers. Findings were summarised using both a narrative approach and meta-analysis. Cohen’s d was calculated at 95% confidence interval (CI) as effect size of between groups differences. Results: Twenty-eight studies comparing adult individuals with a diagnosis of insomnia and healthy controls on neuropsychological measures of EFs were included. Narrative synthesis revealed substantial variability across study findings. Factors that were primarily hypothesised to account for this variability are: objective sleep impairments and test sensitivity. Exploratory meta-analysis showed impaired performance of small to moderate magnitude in individuals with insomnia as compared to controls in reaction times, but not accuracy rates, of inhibitory control (d = −0.32, 95% CI: −0.52 to −0.13) and cognitive flexibility tasks (d = −0.30, 95% CI: −0.59 to −0.01). Performance in working memory tasks was also significantly impacted (d = −0.19, 95% CI: −0.38 to −0.00). Effects sizes were larger when insomnia was associated with objective sleep impairments, rather than normal sleep. Conclusions: We gathered evidence supporting small to moderate deficits in EFs in individuals with insomnia. Due to the small sample size results should be considered preliminary and interpreted carefully

Modeling the motion of a Taylor bubble in a microchannel through a shear-thinning fluid

Applications of multiphase flows in microchannels as chemical and biological reactors and cooling systems for microelectronic devices typically present liquid slugs alternated with bubbles of elongated shape, the Taylor bubbles. These occupy almost entirely the cross-section of the channel and present a hemispherical front and a liquid layer, the lubrication film, which separates the gas from the tube wall. The Taylor bubble perturbs the surrounding fluids activating many transport mechanisms in the proximity of the gas-liquid interface; therefore, the bubble motion significantly influences the heat and mass transfer rates. Although many works deeply investigate the bubble hydrodynamics in Newtonian fluids, the knowledge about the relation between bubble hydrodynamics and rheological properties is insufficient, and studies where the continuous phase exhibits a shear-thinning behavior are missing. Our numerical analysis tries to fill this gap by investigating the motion of a Taylor bubble in a non-Newtonian shear-thinning fluid, modeled by the Carreau viscosity model. First, we validate the results against the Newtonian case and a recent theory for shear-thinning fluids (Picchi et al., Journal of Fluid Mechanics, 2021, 918). Then, we investigate the bubble hydrodynamics far from the validity range of the current models. Finally, we study the scaling of the bubble velocity and lubrication film thickness, extending the current theory to shear-thinning fluids

NSAIDS: Design and Development of Innovative Oral Delivery Systems

Recently, different technologies have been used to transform active pharmaceutical ingredients (APIs) into new dosage forms. Engineered drug delivery systems may modify biopharmaceutical properties of the API achieving either immediate or delayed release according to specific therapeutic needs. Particularly, preprogrammed release of oral formulations delivering the drug at expected times may be useful in chronotherapy of early morning pathologies. The conventional approach when dealing with such diseases is to administer NSAIDs two to three times daily. This approach does not allow to fit drug release with symptoms onset resulting in inefficient therapy and poor patient compliance. NSAIDs may be very effective if administered at least 4–6 h before the pain reaches its peak in the early morning. The solution could be to design delayed drug delivery systems allowing one administration before going to sleep acting in the early morning. This chapter highlights new approaches in developing controlled delivery systems of NSAIDs potentially useful to treat both acute and chronic inflammation. The chapter illustrates the versatility of laminar jet break‐up technology (prilling) to produce gel beads able to control rate and time of drug delivery. A special focus will be on particle‐engineering strategies, i.e., prilling and prilling technique in tandem with microwave or supercritical fluid‐assisted drying

A fast and user-friendly software for quantitative chemical analysis through XRF

X-ray fluorescence (XRF) spectroscopy is a technique widely used for the study and conservation of cultural heritage materials. A Microsoft Excel spreadsheet to determine major (Na, Mg, Al, Si, K, Ca, Fe) and minor (P, Ti, Mn) elements in rocks and other materials by XRF is presented. The code is based on the analytical method proposed a few decades ago by Franzini et al., which is based on the algorithm: Ci = Ii ⋅ ΣKi,j Cj, where Ci is the concentration (expressed as wt%) of the chemical element “i”, Ii is the intensity of the characteristic line, Cj is the concentration of interfering elements, and Ki,j are experimental coefficients that account for the matrix effects (absorption and enhancement). Ki,j have the dimension of mass absorption coefficients and they may be calculated from a set of N reference samples using multivariate regression methods. The algorithm proposed by these authors is particularly suitable for processing samples prepared in the form of pressed powders. The Microsoft Excel spreadsheet allows you to: a) choose a set of reference samples (international or interlaboratory standards); b) evaluate the expected matrix effects on the basis of the XRF total mass absorption coefficients; c) calculate the correction coefficients Ki,j through multivariable regression; d) calculate the analytical accuracy and graphically represent the results; e) choose five samples (monitors) for the correction of instrumental drift. Based on these steps, the software allows you to: i) enter the analytical intensities of major and minor elements measured on the monitors and on unknown samples (the loss on ignition must be determined separately); ii) calculate the correction of the instrumental drift; iii) determine the concentration of elements and express them as wt%

Las novelas policiales de Omar Prego Gadea en los 90. Género y desvíos.

Este trabajo explora las conexiones y desvíos entre las novelas del uruguayo Omar Prego Gadea y el género policial. Es frecuentemente reconocido como un cultor de este género, pero pretendemos precisar con qué vertientes del Policial se identifican sus novelas y en qué aspectos, pensamos, se aparta. Es foco de atención el deslinde de las mismas, de la novela de enigma a la inglesa a pesar de la fuerte presencia de esta en el Río de la Plata, por medio del trabajo de difusión de Jorge Luis Borges y Adolfo Bioy Casares. En este sentido, abordaremos cómo constituyen, desde sus peculiaridades, una búsqueda de sentencia social con respecto a los hechos ocurridos durante la dictadura cívico militar uruguaya de los 70´ y sus repercusiones, por una parte, y la influencia de la obra de Marcel Proust, por otra. En forma lateral, son trabajadas otras intertextualidades que conectan la obra de Prego con sus amigos Juan Carlos Onetti y Julio Cortázar, con Jorge Luis Borges y con Raymond Chandler, así como otras manifestaciones que no le fueron ajenas: el tango y el cine

First record of males of the invasive eucalyptus pest species Leptocybe invasa Fisher & LaSalle, 2004 (Hymenoptera: Eulophidae: Tetrastichinae) from South America

The “blue gum chalcid”, Leptocybe invasa is a pest of eucalyptus worldwide. It has an Australian origin and has expanded into Asia, Europe, Africa and America. L. invasa females were reported from South America in the last decade. Thelytokous parthenogenesis is the most common reproductive mechanism of this pest. However, male adults have been reported from Asia and Southeastern Europe. In this work, L. invasa males are reported for the first time from South America (Argentina) and information on morphological characters of males is provided. The importance of this discovery is highlighted based on recent studies that suggested the existence of two cryptic Leptocybe species in invasive populations.Fil: Aquino, Daniel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Hernandez, Carmen Marcela. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Andorno, Andrea Verónica. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; Argentin