Imbalance between muscle strength development and weight gain in children and young adults in China: serial cross-sectional evidence from 1.33 million students from five successive national surveys between 2000 and 2019.

Background: Over the past decades, Chinese school-aged children and adolescents have experienced a rapid increase in overweight and obesity, but corresponding changes in muscle strength remain unclear. We aimed to elucidate trends in muscle strength development at both national and subnational level, and to investigate whether it has increased proportionally with weight gain.

Methods: Muscle strength (handgrip strength [kg] for upper body and standing broad jump [cm] for lower body) and weight measurements for 1.

Trajectories of night light exposure and risk of overweight and obesity: a 15-year longitudinal cohort study of 218,239 Chinese children.

Background: Light at night (LAN) is found to be associated with elevated overweight and obesity in broad population. However, evidence for the long-term LAN exposure trajectories and its influence to weight gain remained limited, especially to school-aged children who experience critical physical development. We aimed to analyze variations in body weight among children with different LAN exposure profiles, and how varying levels of LAN exposure influenced children's overweight (including obesity) risk overt time.

Accelerating or Slowing: Fine Tuning the De-Threading Kinetics of a T-Shaped Benzimidazolium Pumping Cassette.

Artificial molecular machines (AMMs) rely on precise control of molecular motion, often enabled by mechanically interpenetrated architectures such as pseudorotaxanes. Here, we systematically investigated a library of [2]pseudorotaxanes formed by the combination of T-shaped benzimidazolium threads featuring variable stopper sizes and crown ether wheels (24C6, B24C6, and 23C6), to elucidate how structural parameters govern [2]pseudorotaxane stability and de-threading kinetics. Using ring-closing metathesis and subsequent hydrogenation, we synthesized 10 neutral [2]pseudorotaxanes in high yields (76-87%).

Capturing Ring Opening in Photoexcited Enolic Acetylacetone upon Hydrogen Bond Dissociation by Ultrafast Electron Diffraction.

Photoinduced biological and chemical reactions are often based on key structural transformations of a molecule driven across multiple electronic states. Acetylacetone (AcAc) is a prototypical system for complex chemical pathways involving several conical intersections (CI) and singlet-triplet intersystem crossings (ISC) characterized by distinct geometries. In the gas phase, AcAc is predominantly in a planar ring-like enolic form stabilized by a strong intramolecular O-H···O hydrogen bond.

Reference intervals for hematologic and biochemical values in Cynomolgus monkeys from different breeding populations in China.

The Cynomolgus monkey is the most widely used models in non-clinical studies. As factors like age, gender, and breeding province may affect hematologic and serum biochemical parameters, it is important to establish base values of these parameters by these three factors and to determine the effects of these factors on the parameters. In total, 1794 Cynomolgus monkeys (Male: 901, Female: 893) were selected.

Cortical nonenhancing tumor infiltration: a predictive imaging biomarker for IDH-mutant glioma.

Objective: The aim of this study was to evaluate the cortical nonenhancing tumor infiltration (CONTIN) sign as a predictive imaging biomarker for IDH-mutant gliomas, including diffuse gliomas with and without contrast enhancement.

Methods: Imaging data were collected from patients with diffuse gliomas (grades 2-4) at Beijing Tiantan Hospital (BTH) from January 2019 to December 2021 (training set, n = 526) and from the University of California, San Francisco, preoperative diffuse glioma MRI dataset (UCSF PDGM; validation set, n = 501). Two independent reviewers assessed the CONTIN sign and other radiological features to develop a diagnostic strategy.

Unraveling the heterogeneity of WHO grade 4 gliomas: insights from clinical, imaging, and molecular characterization.

Purpose: The 2021 WHO classification of central nervous system tumors introduced molecular criteria to stratify Grade 4 gliomas, which remain heterogeneous. This study aims to elucidate the clinical, radiological, and molecular characteristics of WHO Grade 4 gliomas, focusing on their prognostic implications and the development of a predictive model for astrocytoma IDH-mutant WHO Grade 4 (A4).

Methods: A retrospective cohort of 223 patients from Beijing Tiantan Hospital was analyzed.

Toward Large-Scale Photonic Chips Using Low-Anisotropy Thin-Film Lithium-Tantalate.

Photonic manipulation of large-capacity data with the advantages of high speed and low power consumption is a promising solution for explosive growth demands in the era of post-Moore. A well-developed lithium-niobate-on-insulator (LNOI) platform has been widely explored for high-performance electro-optic (EO) modulators to bridge electrical and optical signals. However, the photonic waveguides on the x-cut LNOI platform suffer serious polarization-mode conversion/coupling issues because of strong birefringence, making it hard to realize large-scale integration.

Identifying joint association between body fat distribution with high blood pressure among 7 ∼ 17 years using the BKMR model: findings from a cross-sectional study in China.

Background: To investigate the joint associations between various body fat distribution parameters and high blood pressure (HBP) using the Bayesian Kernel Machine Regression (BKMR) model in school-aged children.

Methods: A diverse sample of 7 ∼ 17 years old (N = 1423; 50.25% boys) was recruited for this study.

Ultrafast structural dynamics of UV photoexcited ,-1,3-cyclooctadiene observed with time-resolved electron diffraction.

Conjugated diene molecules are highly reactive upon photoexcitation and can relax through multiple reaction channels that depend on the position of the double bonds and the degree of molecular rigidity. Understanding the photoinduced dynamics of these molecules is crucial for establishing general rules governing the relaxation and product formation. Here, we investigate the femtosecond time-resolved photoinduced excited-state structural dynamics of ,-1,3-cyclooctadiene, a large-flexible cyclic conjugated diene molecule, upon excitation with 200 nm using mega-electron-volt ultrafast electron diffraction and trajectory surface hopping dynamics simulations.

Fast and low energy-consumption integrated Fourier-transform spectrometer based on thin-film lithium niobate.

Integrated miniature spectrometers have impacts in industry, agriculture, and aerospace applications due to their unique advantages in portability and energy consumption. Although existing on-chip spectrometers have achieved breakthroughs in key performance metrics, such as, a high resolution and a large bandwidth, their scanning speed and energy consumption still hinder practical applications of such devices. Here, a stationary Fourier transform spectrometer is introduced based on a Mach-Zehnder interferometer structure on thin-film lithium niobate.

The association between the knowledge, perception, and practice of dietary supplement among Chinese adults.

Introduction: Rapid growth has been found in the market of dietary supplements (DSs) in China. However, studies about the knowledge level, intentions, and behavior related to DS remained limited in the Chinese population. This study aimed to explore the knowledge level, perception, and practice toward DS among Chinese adults.

Element-specific ultrafast lattice dynamics in FePt nanoparticles.

Light-matter interaction at the nanoscale in magnetic alloys and heterostructures is a topic of intense research in view of potential applications in high-density magnetic recording. While the element-specific dynamics of electron spins is directly accessible to resonant x-ray pulses with femtosecond time structure, the possible element-specific atomic motion remains largely unexplored. We use ultrafast electron diffraction (UED) to probe the temporal evolution of lattice Bragg peaks of FePt nanoparticles embedded in a carbon matrix following excitation by an optical femtosecond laser pulse.

Evaluating the combined estrogenic effects of plant growth regulators electrochemical and E-Screen methods.

The study shows that plant growth regulators (PGRs) have estrogenic effects, which may disrupt the normal physiological functions of endogenous estrogen in organisms. This study used electrochemical methods to investigate the electrochemical behavior and estrogenic effects of PGRs gibberellic acid (GA), ethylene (ETH), and naphthalene acetic acid (NAA) on estrogen-free human breast cancer cells (MCF-7) cells when exposed individually or in combination. The results indicate that GA, ETH, and NAA, whether used alone or in combination, exhibit estrogenic effects on MCF-7 cells.

Exploring the Causal Association between Morning Diurnal Preference and Psychiatric Disorders: A Bidirectional Two-Sample Mendelian Randomization Analysis.

Background: The causal connection between morning diurnal preference and psychiatric disorders remains enigmatic. Using bidirectional two-sample Mendelian randomization (MR), we aim to explore the potential causal associations between morning diurnal preference and seven prominent psychiatric disorders.

Methods: MR is a genetic epidemiological method that leverages genetic variants as instrumental variables to infer causal associations between exposures and outcomes.

UV-Induced Reaction Pathways in Bromoform Probed with Ultrafast Electron Diffraction.

For many chemical reactions, it remains notoriously difficult to predict and experimentally determine the rates and branching ratios between different reaction channels. This is particularly the case for reactions involving short-lived intermediates, whose observation requires ultrafast methods. The UV photochemistry of bromoform (CHBr) is among the most intensely studied photoreactions.

Multi-objective Bayesian active learning for MeV-ultrafast electron diffraction.

Ultrafast electron diffraction using MeV energy beams(MeV-UED) has enabled unprecedented scientific opportunities in the study of ultrafast structural dynamics in a variety of gas, liquid and solid state systems. Broad scientific applications usually pose different requirements for electron probe properties. Due to the complex, nonlinear and correlated nature of accelerator systems, electron beam property optimization is a time-taking process and often relies on extensive hand-tuning by experienced human operators.

Giant Terahertz Birefringence in an Ultrathin Anisotropic Semimetal.

Manipulating the polarization of light at the nanoscale is key to the development of next-generation optoelectronic devices. This is typically done via waveplates using optically anisotropic crystals, with thicknesses on the order of the wavelength. Here, using a novel ultrafast electron-beam-based technique sensitive to transient near fields at THz frequencies, we observe a giant anisotropy in the linear optical response in the semimetal WTe and demonstrate that one can tune the THz polarization using a 50 nm thick film, acting as a broadband wave plate with thickness 3 orders of magnitude smaller than the wavelength.

Direct observation of strong momentum-dependent electron-phonon coupling in a metal.

Phonon scattering in metals is one of the most fundamental processes in materials science. However, understanding such processes has remained challenging and requires detailed information on interactions between phonons and electrons. We use an ultrafast electron diffuse scattering technique to resolve the nonequilibrium phonon dynamics in femtosecond-laser-excited tungsten in both time and momentum.

Monitoring the Evolution of Relative Product Populations at Early Times during a Photochemical Reaction.

Identifying multiple rival reaction products and transient species formed during ultrafast photochemical reactions and determining their time-evolving relative populations are key steps toward understanding and predicting photochemical outcomes. Yet, most contemporary ultrafast studies struggle with clearly identifying and quantifying competing molecular structures/species among the emerging reaction products. Here, we show that mega-electronvolt ultrafast electron diffraction in combination with molecular dynamics calculations offer a powerful route to determining populations of the various isomeric products formed after UV (266 nm) excitation of the five-membered heterocyclic molecule 2(5)-thiophenone.