Differential Coupling of Adult-Born Granule Cells to Parvalbumin and Somatostatin Interneurons

A strong GABAergic tone imposes sparse levels of activity in the dentate gyrus of the hippocampus. This balance is challenged by the addition of new granule cells (GCs) with high excitability. How developing GCs integrate within local inhibitory networks remains unknown. We used optogenetics to study synaptogenesis between new GCs and GABAergic interneurons expressing parvalbumin (PV-INs) and somatostatin (SST-INs). PV-INs target the soma, and synapses become mature after 6 weeks. This transition is accelerated by exposure to an enriched environment. PV-INs exert efficient control of GC spiking and participate in both feedforward and feedback loops, a mechanism that would favor lateral inhibition and sparse coding. SST-INs target the dendrites, and synapses mature after 8 weeks. Outputs from GCs onto PV-INs develop faster than those onto SST-INs. Our results reveal a long-lasting transition wherein adult-born neurons remain poorly coupled to inhibition, which might enhance activity-dependent plasticity of input and output synapses. Groisman et al. examine the integration of adult-born granule cells (GCs) to inhibitory networks of the adult hippocampus. Synapse maturation is remarkably slow for parvalbumin and somatostatin interneurons, both for connections toward and from GCs. Inhibition controls the activity of new GCs late in development.Fil: Groisman, Ayelén Ivana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Yang, Sung Min. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Schinder, Alejandro Fabián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentin

Cross-Catalysis between Self-Replicators of Different Handedness

Life, as we know it today, requires the homochirality of its constituents. Yet it is likely that the prebiotic soup was a racemic mixture of molecules. It remains an open question at which point in evolution homochirality became necessary for life. Self-replicating molecules are expected to be a possible link between inanimate and animate matter. We here report the interplay between chirality and self-replication, and specifically investigated cross-catalysis between replicating species containing building blocks of different handedness. We find that, although replication of species from the same handedness is more efficient in isolated systems, nonstereoselective cross-catalysis dominates and leads to the formation of heterochiral self-replicators when a racemic mixture of building blocks is provided. These results demonstrate that homochirality is not a prerequisite for self-replication, and that chiral symmetry breaking could have occurred after the emergence of self-replicating systems from racemic mixtures

Enterobacteriaceae bacteremias among cancer patients: an observational cohort study

SummaryBackgroundEnterobacteriaceae bacteremia is a common complication in patients with neoplasm. The cancer itself, chemotherapy-induced immunosuppression, and other cancer-related procedures play a role as predisposing factors for this condition. However, despite the clear association between cancer and Enterobacteriaceae bacteremia, the distinctive clinical characteristics of patients with cancer presenting with Enterobacteriaceae bacteremia have not been well established.MethodsThe population studied was a prospective cohort of adult hospitalized patients with Enterobacteriaceae bacteremia in a tertiary care hospital. We compared the clinical variables and microbiological features between patients with an underlying neoplasm (n=203) and those without (n=259). STATA software was used for statistical association analysis.ResultsIn a bivariate analysis, older age, prior exposure to aminopenicillins, fewer days of symptoms, biliary source of bacteremia, greater severity of APACHE II score, lower white blood cell and platelet counts, and the presence of Klebsiella pneumoniae were more common in the neoplasm group. In a multivariable analysis, K. pneumoniae bacteremia (odds ratio (OR) 6.13, 95% confidence interval (CI) 1.65–22.71; p=0.007), APACHE II score (OR 1.18, 95% CI 1.05–1.34; p=0.007), and exposure to aminopenicillins (OR 28.84, 95% CI 1.94–429.3; p=0.015) were associated with neoplasm. K. pneumoniae bacteremia was more commonly present in patients with lung and gastrointestinal cancers.ConclusionsWe have confirmed the association of K. pneumoniae bacteremia with underlying neoplastic disease, especially with gastrointestinal malignancies, which may allow stratification for initial empiric antibiotic therapy in this subset of patients. Prior exposure to aminopenicillins in the neoplasm group might contribute to this finding

C programs for solving the time-dependent Gross-Pitaevskii equation in a fully anisotropic trap

We present C programming language versions of earlier published Fortran programs (Muruganandam and Adhikari, Comput. Phys. Commun. 180 (2009) 1888) for calculating both stationary and non-stationary solutions of the time-dependent Gross-Pitaevskii (GP) equation. The GP equation describes the properties of dilute Bose-Einstein condensates at ultra-cold temperatures. C versions of programs use the same algorithms as the Fortran ones, involving real- and imaginary-time propagation based on a split-step Crank-Nicolson method. In a one-space-variable form of the GP equation, we consider the one-dimensional, two-dimensional, circularly-symmetric, and the three-dimensional spherically-symmetric harmonic-oscillator traps. In the two-space-variable form, we consider the GP equation in two-dimensional anisotropic and three-dimensional axially-symmetric traps. The fully-anisotropic three-dimensional GP equation is also considered. In addition to these twelve programs, for six algorithms that involve two and three space variables, we have also developed threaded (OpenMP parallelized) programs, which allow numerical simulations to use all available CPU cores on a computer. All 18 programs are optimized and accompanied by makefiles for several popular C compilers. We present typical results for scalability of threaded codes and demonstrate almost linear speedup obtained with the new programs, allowing a decrease in execution times by an order of magnitude on modern multi-core computers.Comment: 8 pages, 1 figure; 18 C programs included (to download, click other and download the source

APIHarvest: Harvesting API Information from Various Online Sources

Using APIs to develop software applications is the norm. APIs help developers to build applications faster as they do not need to reinvent the wheel. It is therefore important for developers to understand the APIs that they plan to use. Developers should also make themselves aware of relevant information updates about APIs. In order to do so, developers need to find and keep track of relevant information about the APIs that they are concerned with. Yet, the API information is scattered across various online sources, which makes it difficult to track by hand. Moreover, identifying content that is related to an API is not trivial. Motivated by these challenges, in this work, we introduce a tool named \tool that aims to ease the process of finding API information from various online sources. \tool is built on works that link APIs or libraries to various online sources. It supports finding API information on GitHub repositories, Stack Overflow's posts, tweets, YouTube videos, and common vulnerability and exposure (CVE) entries; and is extensible to support other sources

APISENS- Sentiment Scoring Tool for APIs with Crowd-Knowledge

Utilizing pre-existing software artifacts, such as libraries and Application Programming Interfaces (APIs), is crucial for software development efficiency. However, the abundance of artifacts that provide similar functionality can lead to confusion among developers, resulting in a challenge for proper selection and implementation. Through our preliminary investigation, we found that utilizing the collective knowledge of a crowd can greatly assist developers in acquiring a thorough and complete understanding of the complexities involved in the software development process. Especially as emotions are an inseparable part of human nature, it influences developers' activities. In this regard, we attempt to build a tool that can retrieve sentiment information for software APIs so that developers can determine APIs to utilize for their tasks. We employ the dataset from the most popular platforms (i.e., Twitter and YouTube) to build our research prototype. The source code, tool, and demo video are available on GitHub at \url{https://github.com/FalconLK/APISens}