Active learning of molecular data for task-specific objectives.

Active learning (AL) has shown promise to be a particularly data-efficient machine learning approach. Yet, its performance depends on the application, and it is not clear when AL practitioners can expect computational savings. Here, we carry out a systematic AL performance assessment for three diverse molecular datasets and two common scientific tasks: compiling compact, informative datasets and targeted molecular searches.

Surface-Area-to-Volume Ratio Determines Surface Tensions in Microscopic, Surfactant-Containing Droplets.

The surface composition of aerosol droplets is central to predicting cloud droplet number concentrations, understanding atmospheric pollutant transformation, and interpreting observations of accelerated droplet chemistry. Due to the large surface-area-to-volume ratios of aerosol droplets, adsorption of surfactant at the air-liquid interface can deplete the droplet's bulk concentration, leading to droplet surface compositions that do not match those of the solutions that produced them. Through direct measurements of individual surfactant-containing, micrometer-sized droplet surface tensions, and fully independent predictive thermodynamic modeling of droplet surface tension, we demonstrate that, for strong surfactants, the droplet's surface-area-to-volume ratio becomes the key factor in determining droplet surface tension rather than differences in surfactant properties.

Miniature microscopes for manipulating and recording in vivo brain activity.

Here we describe the development and application of miniature integrated microscopes (miniscopes) paired with microendoscopes that allow for the visualization and manipulation of neural circuits in superficial and subcortical brain regions in freely behaving animals. Over the past decade the miniscope platform has expanded to include simultaneous optogenetic capabilities, electrically-tunable lenses that enable multi-plane imaging, color-corrected optics, and an integrated data acquisition platform that streamlines multimodal experiments. Miniscopes have given researchers an unprecedented ability to monitor hundreds to thousands of genetically-defined neurons from weeks to months in both healthy and diseased animal brains.

An application of probability density function for the analysis of PM2.5 concentration during the COVID-19 lockdown period.

The first Covid-19 patient in India was reported on January 30, 2020 at the state of Kerala. The patient number rose to three by February 3, 2020. In the month of March 2020, the transmissions started to increase when the people started to return back to India from the Covid-19 affected countries.

Hair transplantation by follicular unit extraction for male androgenetic alopecia: A retrospective observational study from two centers.

Background: Follicular unit extraction (FUE) is the most popular method of hair transplantation in today's world. Hair transplantation in androgenetic alopecia (AGA) in males can restore the frontal hairline and provide hair density in alopecic areas to the satisfaction of most patients.

Methods: Consecutive male patients of AGA who underwent hair transplantation by FUE method in two centers between the period of January 2016 and June 2017 have been included in this study based on inclusion and exclusion criteria.

Chemical diversity in molecular orbital energy predictions with kernel ridge regression.

Instant machine learning predictions of molecular properties are desirable for materials design, but the predictive power of the methodology is mainly tested on well-known benchmark datasets. Here, we investigate the performance of machine learning with kernel ridge regression (KRR) for the prediction of molecular orbital energies on three large datasets: the standard QM9 small organic molecules set, amino acid and dipeptide conformers, and organic crystal-forming molecules extracted from the Cambridge Structural Database. We focus on the prediction of highest occupied molecular orbital (HOMO) energies, computed at the density-functional level of theory.

Deep Learning Spectroscopy: Neural Networks for Molecular Excitation Spectra.

Deep learning methods for the prediction of molecular excitation spectra are presented. For the example of the electronic density of states of 132k organic molecules, three different neural network architectures: multilayer perceptron (MLP), convolutional neural network (CNN), and deep tensor neural network (DTNN) are trained and assessed. The inputs for the neural networks are the coordinates and charges of the constituent atoms of each molecule.

View from Silicon Valley: Maximizing the Scientific Impact of Global Brain Initiatives through Entrepreneurship.

In this era of technology-driven global neuroscience initiatives, the role of the neurotechnology industry remains woefully ambiguous. Here, we explain why industry is essential to the success of these global initiatives, and how it can maximize the scientific impact of these efforts by (1) scaling and ultimately democratizing access to breakthrough neurotechnologies, and (2) commercializing technologies as part of integrated, end-to-end solutions that accelerate neuroscientific discovery.

Direct Imaging of Hippocampal Epileptiform Calcium Motifs Following Kainic Acid Administration in Freely Behaving Mice.

Prolonged exposure to abnormally high calcium concentrations is thought to be a core mechanism underlying hippocampal damage in epileptic patients; however, no prior study has characterized calcium activity during seizures in the live, intact hippocampus. We have directly investigated this possibility by combining whole-brain electroencephalographic (EEG) measurements with microendoscopic calcium imaging of pyramidal cells in the CA1 hippocampal region of freely behaving mice treated with the pro-convulsant kainic acid (KA). We observed that KA administration led to systematic patterns of epileptiform calcium activity: a series of large-scale, intensifying flashes of increased calcium fluorescence concurrent with a cluster of low-amplitude EEG waveforms.

Miniature microscopes for large-scale imaging of neuronal activity in freely behaving rodents.

Recording neuronal activity in behaving subjects has been instrumental in studying how information is represented and processed by the brain. Recent advances in optical imaging and bioengineering have converged to enable time-lapse, cell-type specific recordings of neuronal activities from large neuronal populations in deep-brain structures of freely behaving rodents. We will highlight these advancements, with an emphasis on miniaturized integrated microscopy for large-scale imaging in freely behaving mice.

Zolpidem reduces hippocampal neuronal activity in freely behaving mice: a large scale calcium imaging study with miniaturized fluorescence microscope.

Therapeutic drugs for cognitive and psychiatric disorders are often characterized by their molecular mechanism of action. Here we demonstrate a new approach to elucidate drug action on large-scale neuronal activity by tracking somatic calcium dynamics in hundreds of CA1 hippocampal neurons of pharmacologically manipulated behaving mice. We used an adeno-associated viral vector to express the calcium sensor GCaMP3 in CA1 pyramidal cells under control of the CaMKII promoter and a miniaturized microscope to observe cellular dynamics.

Long-term dynamics of CA1 hippocampal place codes.

Using Ca(2+) imaging in freely behaving mice that repeatedly explored a familiar environment, we tracked thousands of CA1 pyramidal cells' place fields over weeks. Place coding was dynamic, as each day the ensemble representation of this environment involved a unique subset of cells. However, cells in the ∼15-25% overlap between any two of these subsets retained the same place fields, which sufficed to preserve an accurate spatial representation across weeks.

Miniaturized integration of a fluorescence microscope.

The light microscope is traditionally an instrument of substantial size and expense. Its miniaturized integration would enable many new applications based on mass-producible, tiny microscopes. Key prospective usages include brain imaging in behaving animals for relating cellular dynamics to animal behavior.

Advances in light microscopy for neuroscience.

Since the work of Golgi and Cajal, light microscopy has remained a key tool for neuroscientists to observe cellular properties. Ongoing advances have enabled new experimental capabilities using light to inspect the nervous system across multiple spatial scales, including ultrastructural scales finer than the optical diffraction limit. Other progress permits functional imaging at faster speeds, at greater depths in brain tissue, and over larger tissue volumes than previously possible.

Intra-peritoneal duodenal perforation caused by delayed migration of endobiliary stent: a case report.

Endoscopic biliary stenting is an accepted modality of palliation of malignant biliary obstructions. Delayed stent migration causing intra-peritoneal perforation of duodenum, is a rare life threatening complication. Proximal adhesion of stent to the tumor is believed to increase the intensity of distal trauma produced by the intra-duodenal segment, preventing its adaptation to intestinal peristalsis and causing perforation.

New slow-releasing molybdenum fertilizer.

This paper describes a new water-insoluble molybdenum compound that has been developed as a slow-release fertilizer. The compound is an inorganic polymer formed by inclusion of molybdenum within a long-chain polyphosphate structure. It was designed by a process of "reverse engineering" of the molecule.

Splenic artery aneurysm--a rare cause for extrahepatic portal venous obstruction: a case report.

Splenic artery aneurysm is a rare yet very important clinical entity because of its potential for rupture with fatal consequences. Most of the splenic artery aneurysms are found in the middle and distal third of the splenic artery and are usually small (< or = 2 cm) at the time of diagnosis. We describe a rare case of large (5x4 cm) juxta-ostial splenic artery aneurysm causing compression of the splenoportal confluence and adjoining proximal portal vein in a 40-year-old woman.