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Successful pregnancy relies directly on the placenta’s complex, dynamic, gene-regulatory networks. Disruption of this vast collection of intercellular and intracellular programs leads to pregnancy complications and developmental defects. In the present study, we generated a comprehensive, spatially resolved, multimodal cell census elucidating the molecular architecture of the first trimester human placenta. We utilized paired single-nucleus (sn)ATAC (assay for transposase accessible chromatin) sequencing and RNA sequencing (RNA-seq), spatial snATAC-seq and RNA-seq, and in situ sequencing and hybridization mapping of transcriptomes at molecular resolution to spatially reconstruct the joint epigenomic and transcriptomic regulatory landscape. Paired analyses unraveled intricate tumor-like gene expression and transcription factor motif programs potentially sustaining the placenta in a hostile uterine environment; further investigation of gene-linked cis-regulatory elements revealed heightened regulatory complexity that may govern trophoblast differentiation and placental disease risk. Complementary spatial mapping techniques decoded these programs within the placental villous core and extravillous trophoblast cell column architecture while simultaneously revealing niche-establishing transcriptional elements and cell–cell communication. Finally, we computationally imputed genome-wide, multiomic single-cell profiles and spatially characterized the placental chromatin accessibility landscape. This spatially resolved, single-cell multiomic framework of the first trimester human placenta serves as a blueprint for future studies on early placental development and pregnancy.

Developing a stable, reliable, and industrially compatible method to control hydrophobicity is crucial for separation, transportation, and the generation of special surfaces. An e-HMS-PDMS silica gel nanoparticle coating was prepared using a two-step electron beam irradiation (EBI) process, consisting of (i) grafting of two organic groups onto thiol-functionalized hollow mesoporous silica (HMS-SH) with 10 MeV EBI and (ii) curing of polydimethylsiloxane (PDMS) onto silicone rubber using the HMS hybrid materials prepared in step i as an additive with 200 keV EBI. The tuneable grafting of functional groups and the surface properties of the silica, which was embedded in the PDMS layer, allowed us to precisely control the hydrophilicity of the PDMS layer by means of altering the grafting gradient of the silica and the loading ratio of the monomers. A diverse range of vinyl-structured monomers can be used in this method, and the selection of suitable monomers is vital in determining the physical properties of the coating layer. The hydrophilicity of the coating can be linearly controlled within a specific range (50° to 155°) by using suitable monomers, allowing for the design of surfaces with specific hydrophilic and hydrophobic requirements.Keywords: Electron beam irradiation; Nanoparticle composite coating; Hydrophilicity/hydrophobicity; Thiol-ene click reaction.

High-content cell profiling has proven invaluable for single-cell phenotyping in response to chemical perturbations. However, methods with improved throughput, information content and affordability are still needed. We present a new high-content spectral profiling method named vibrational painting (VIBRANT), integrating mid-infrared vibrational imaging, multiplexed vibrational probes and an optimized data analysis pipeline for measuring single-cell drug responses. Three infrared-active vibrational probes were designed to measure distinct essential metabolic activities in human cancer cells. More than 20,000 single-cell drug responses were collected, corresponding to 23 drug treatments. The resulting spectral profile is highly sensitive to phenotypic changes under drug perturbation. Using this property, we built a machine learning classifier to accurately predict drug mechanism of action at single-cell level with minimal batch effects. We further designed an algorithm to discover drug candidates with new mechanisms of action and evaluate drug combinations. Overall, VIBRANT has demonstrated great potential across multiple areas of phenotypic screening.

Deep learning-based methods have greatly improved the performance of hyperspectral image (HSI) classification over the past several years. Nevertheless, current deep learning methods require training and deploying an independent model for each hyperspectral data domain. Representations learned for one data domain can hardly be generalized to other data domains, so multiple models are needed in real-world applications when data from multiple domains are involved. In this article, we design a single neural network that learns universal representations simultaneously from multiple hyperspectral remote sensing data domains. The universal convolutional neural network (CNN) adapts its behavior to different hyperspectral datasets. The majority of parameters of the network are shared to learn common knowledge from multiple datasets. A small number of domain-specific parameters are assigned to handle the domain shift. In addition, we propose a two-step training strategy to fully utilize the capacity of the universal network. Experiments conducted on seven HSI datasets demonstrate that the proposed universal network outperforms multiple individual specialized single-domain networks.

Understanding metabolism is indispensable in unraveling the mechanistic basis of many physiological and pathological processes. However, in situ metabolic imaging tools are still lacking. Here we introduce a framework for mid-infrared (MIR) metabolic imaging by coupling the emerging high-information-throughput MIR microscopy with specifically designed IR-active vibrational probes. We present three categories of small vibrational tags including azide bond, 13C-edited carbonyl bond and deuterium-labeled probes to interrogate various metabolic activities in cells, small organisms and mice. Two MIR imaging platforms are implemented including broadband Fourier transform infrared microscopy and discrete frequency infrared microscopy with a newly incorporated spectral region (2,000–2,300 cm−1). Our technique is uniquely suited to metabolic imaging with high information throughput. In particular, we performed single-cell metabolic profiling including heterogeneity characterization, and large-area metabolic imaging at tissue or organ level with rich spectral information.

In this Tools of the Trade article, Xinwen Liu describes the development of VIBRANT, a vibrational spectroscopy method for high-content phenotypic profiling, and highlights its use to predict drug mechanisms of action or identify potential drug candidates.

Normal saline (NS) is the most widely used agent in the medical field. However, from its origin to its widespread application, it remains a mystery. Moreover, there is an ongoing debate on whether its existence is reasonable, harmful to the human body, or will still exist in the future. The current review traces back to the origins of NS and provides a brief overview of the current situation of infusion. The purpose may shed some light on the possibility of the existence of NS in the future by elaborating on the origin of NS and the research status of the impact of NS on the human body.

Abstract: The two-state mechanism of the reaction of Nb(NH2)3 with N2O on the singlet and triplet potential energy surfaces has been investigated at the B3LYP level. Crossing points between the potential energy surfaces have been located using different methods. Analysis of the strain model shows that the singlet state of the four-coordinate (N2O)Nb(NH2)3 complex with N2O bonded via terminal N atom coordination (1 2) is more stable in the initial stage of reaction, since the bending of the N2O fragment [E def(N2O) = 86.1 kcal mol−1] results in an energy splitting of the doubly degenerate LUMO; the low-energy LUMO can now strongly couple with the occupied Nb-localized d orbitals, forming a back-bond and transferring charge (q = 0.82 e) from Nb(NH2)3 to the N2O ligand. Going from 3 2 to 1 2, the reacting system changes spin multiplicity near the MECP (minimal energy crossing point) region, which takes place with a spin crossing barrier of 9.6–10.0 kcal mol−1. Analysis of spin-orbit coupling (SOC) indicates that MECP will produce a significant SOC matrix element. The value of SOC is 111.52 cm−1, due to the electron shift between two perpendicular ϕ orbitals with the same rotation direction, and the magnitude of the spin-multi-plicity mixing increases in the small energy gap between high- and low-spin states, greatly enhancing the probability of intersystem crossing. The probabilities of single (P 1ISC) and double (P 2ISC) passes estimated at MECP (SOC = 111.52 cm−1) are approximately 1.17×10−2 and 2.32×10−2, respectively.

Abstract: The optimized geometries of the three complexes between MeH n (Me=Na, Mg, Be; n=1 or 2) and SiH4 have been calculated at the B3LYP/6-311++g**, MP2/6-311++g(3df,3pd) and MP2/aug-cc-pvtz levels, respectively. The red-shift inverse hydrogen bonds (IHBs) based on Si-H, an electron donor, were reported. The calculated binding energies with basis set super-position error (BSSE) correction of the three complexes are −5.98, −8.65 and −3.96 kJ mol−1 (MP2/6-311++g(3df, 3pd)), respectively, which agree with the results obtained via MP2/aug-cc-pvtz (−6.18, −9.12 and −4.28 kJ mol−1, respectively). The relative stabilities of the three complexes are in the order of SiH4…MgH2 > SiH4…NaH > SiH4…BeH2. Natural bond orbital theory (NBO) analysis and the chemical shift calculation of the related atoms revealed that the charges flow from SiH4 to MeH n and the chemical shifts of the interacting H shift to downfield. Here, the Si1-H3 of SiH4 acts as both a bond hydrogen donor and an electron donor. Therefore, compared with conventional hydrogen bonds, they formed IHB complexes. Atoms in molecules (AIM) theory have been used to investigate the topological properties of the critical points in the three IHB structures.

Radiation‐induced grafting of sodium styrene sulfonate and acrylic acid onto high‐density polyethylene (HDPE) membranes was studied by the preirradiation technique. Grafting was carried out using an electronic beam from a 2‐MeV accelerator at room temperature. The effects of the type of solvent, inhibitor concentration, preirradiation atmosphere, monomer concentration, and storage time of preirradiated HDPE membranes on the grafting yield were investigated. Easy control over the grafting yield was achieved by proper selection of the reaction conditions. IR spectroscopy analysis of the grafted membrane confirmed the existence of sulfonate and carboxylic acid groups in the grafted membranes. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3401–3405, 2006

Strong acid cation‐exchange membranes were obtained by radiation‐induced grafting of acrylic acid and sodium styrene sulfonate onto high‐density polyethylene (HDPE). Thermal and chemical properties of the cation‐exchange membranes were investigated. The effectiveness of &bond;SO3Na containing membranes was conformed in inducing high resistance to oxidative degradation. The char residue of the grafted HDPE is greater than that of ungrafted HDPE. It shows that the branch chains, including &bond;SO3Na and &bond;COOH groups, give catalytic impetus to the charring. The crystallinity of the grafted membranes was decreased when increasing the grafting yield. It was assumed that the decreased crystallinity was due to collective effects of the inherent crystallinity dilution by the amorphous grafted chains and the crystal distortion of the HDPE component. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99:3396–3400, 2006

Optical coherence tomography (OCT) suffers from random noises which degrade contrast of image, these noises can not effectively be wiped off by filtering technique. Characteristics of random noises were discussed and analyzed, noise influences were identified on image. The method of wavelet transform is presented for image denoising. The result shows that the method can reduce image noises.

Monte-Carlo simulation was used to study photon distribution in brain tissue, look ahead distance (LAD) empirical formula and theoretical model of near-infrared (NIR) neurosurgical manipulation microwound probe were obtained from the light distribution simulation. LAD empirical formula was verified by phantom and intralipid experiments. The experiment results are valuable for designing neurosurgical microwound probe.

The principle of the algorithm for stability near infrared (NIR) optical Tomography (CT) is introduced. The forward problem of optical CT is how to solve the Boltzmann transmitting equation based on finite rlement method (FEM). The influence of high reduced scattering coefficient and high absorption coefficient distribution of simulation background was discussed. The inverse problem is to reconstruct the map of the background tissue from the boundary data, and the image reconstruction algorithm is the key problem for optical CT. Generic algorithm (GA) and FEM simulation was used to solve the inverse problem.