Neuro-cardiac-guided transcranial magnetic stimulation: Unveiling the modulatory effects of low-frequency and high-frequency stimulation on heart rate.

Transcranial magnetic stimulation (TMS) is pivotal in the field of major depressive disorder treatment. Due to its unsatisfied response rate, an increasing number of researchers have turned their attention towards optimizing TMS site localization. Since the influence of TMS in reducing heart rate (HR) offers insights into its regulatory impact on the autonomic nervous system, a novel approach, called neurocardiac-guided TMS (NCG-TMS), has been proposed to pinpoint the brain region eliciting the maximal individual reduction in HR as a personalized optimal stimulation target. The present study intends to systematically explore the effects of stimulation frequency, left and right hemispheres, stimulation positions, and individual differences on HR modulation using the NCG-TMS method. In experiment 1, low-frequency TMS was administered to 30 subjects, and it was found that low-frequency NCG-TMS significantly downregulated HR, with more significant effects in the right hemisphere than in the left hemisphere and the prefrontal cortex than in other brain areas. In experiment 2, high-frequency NCG-TMS stimulation was administered to 30 subjects, showing that high-frequency NCG-TMS also downregulated HR and had the greatest modulatory effect in the right prefrontal region. Simultaneously, both experiments revealed sizeable individual variability in the optimal stimulation site, which in turn validated the feasibility of the NCG-TMS method. In conclusion, the present experiments independently replicated the effect of NCG-TMS, provided an effect of high-/low-frequency TMS stimulation to downregulate HR, and identified a right lateralization of the HR modulation effect.

Investigating Temperature-Dependent Microscopic Deformation in Tough and Self-Healing Hydrogel Using Time-Resolved USAXS.

Tough and self-healing hydrogels are typically sensitive to loading rates or temperatures due to the dynamic nature of noncovalent bonds. Understanding the structure evolution under varying loading conditions can provide valuable insights for developing new tough soft materials. In this study, polyampholyte (PA) hydrogel with a hierarchical structure is used as a model system. The evolution of the microscopic structure during loading is investigated under varied loading temperatures. By combining ultra-small angle X-ray scattering (USAXS) and Mooney-Rivlin analysis, it is elucidated that the deformation of bicontinuous hard/soft phase networks is closely correlated with the relaxation dynamics or strength of noncovalent bonds. At high loading temperatures, the gel is soft and ductile, and large affine deformation of the phase-separated networks is observed, correlated with the fast relaxation dynamics of noncovalent bonds. At low loading temperatures, the gel is stiff, and nonaffine deformation occurs from the onset of loading due to the substantial breaking of noncovalent bonds and limited chain mobility as well as weak adaptation of phase deformation to external stretch. This work provides an in-depth understanding of the relationship between structure and performance of tough and self-healing hydrogels.

Facet-Defect Tolerant Bi-Doped Cs2AgxNa1-xInCl6 Nanoplatelets with a Near-Unity Photoluminescence Quantum Yield.

We report the colloidal synthesis of Bi-doped Cs2AgxNa1-xInCl6 double perovskite nanoplatelets (NPLs) exhibiting a near-unity photoluminescence quantum yield (PLQY), a record emission efficiency for nanoscale lead-free metal halides. A combination of optical spectroscopies revealed that nonradiative decay processes in the NPL were suppressed, indicating a well-passivated surface. By comparison, nanocubes with the same composition and surface ligands as the NPLs had a PLQY of only 40%. According to our calculations, the type of trap states arising from the presence of surface defects depends on their specific location: defects located on the facets of nanocubes generate only shallow traps, while those at the edges result in deep traps. In NPLs, due to their extended basal facets, most of the surface defects are facet defects. This so-called facet-defect tolerant behavior of double perovskites explains the more efficient optical emission of NPLs compared to that of nanocubes.

Biasing Divergent Polycyclic Aromatic Hydrocarbon Oxidation Pathway by Solvent-Free Mechanochemistry.

Precise control in reaction selectivity is the goal in modern organic synthesis, and it has been widely studied throughout the synthetic community. In comparison, control of divergent reactivity of a given reagent under different reaction conditions is relatively less explored aspect of chemical selectivity. We herein report an unusual reaction between polycyclic aromatic hydrocarbons and periodic acid H5IO6 (1), where the product outcome is dictated by the choice of reaction conditions. That is, reactions under solution-based condition give preferentially C-H iodination products, while reactions under solvent-free mechanochemical condition provide C-H oxidation quinone products. Control experiments further indicated that the iodination product is not a reaction intermediate toward the oxidation product and vice versa. Mechanistic studies unveiled an in situ crystalline-to-crystalline phase change in 2 during ball-milling treatment, where we assigned it as a polymeric hydrogen-bond network of 1. We believe that this polymeric crystalline phase shields the more embedded electrophilic I═O group of 1 from C-H iodination and bias a divergent C-H oxidation pathway (with I═O) in the solid state. Collectively, this work demonstrates that mechanochemistry can be employed to completely switch a reaction pathway and unmask hidden reactivity of chemical reagents.

Molecular characterization of a novel clade echovirus 3 isolated from patients with hand-foot-and-mouth disease in southwest China.

Echovirus 3 (E3) belongs to the species Enterovirus B. Currently, three nearly whole-genome sequences of E3 are available in GenBank in China. In this study, we determined the whole genomic sequences of six E3 strains isolated from the stools of patients with hand-foot-and-mouth disease in Southwest China in 2022. Their nucleotide and amino acid sequences shared 82.1%-86.4% and 96.6%-97.2% identity with the prototype Morrisey strain, respectively, and showed 87.1% and 97.2% mutual identity. The six E3 strains are not clustered with other Chinese strains and formed a novel subgenotype (C6) with the recent American and British strains. Recombination analyses revealed that intertype recombination had occurred in the 2 C and 3D regions of the six E3 strains with coxsackieviruses B5 and B4, respectively. This study augments the nearly whole-genome sequences of E3 in the GenBank database and extends the molecular characterization of this virus in China.

Multimodal ultrasound imaging: A method to improve the accuracy of diagnosing thyroid TI-RADS 4 nodules.

Thyroid nodule is a common and frequently occurring disease in the neck in recent years, and ultrasound has become the preferred imaging diagnosis method for thyroid nodule due to its advantages of noninvasive, nonradiation, real-time, and repeatable. The thyroid imaging, reporting and data system (TI-RADS) classification standard scores suspicious nodules that are difficult to determine benign and malignant as grade 4, and further pathological puncture is recommended clinically, which may lead to a large number of unnecessary biopsies and operations. Including conventional ultrasound, ACR TI-RADS, shear wave elastography, super microvascular imaging, contrast enhanced ultrasound, "firefly," artificial intelligence, and multimodal ultrasound imaging used in combination. In order to identify the most clinically significant malignant tumors when reducing invasive operations. This article reviews the application and research progress of multimodal ultrasound imaging in the diagnosis of TI-RADS 4 thyroid nodules.

Cobalt-catalyzed peri-selective alkoxylation of 1-naphthylamine derivatives.

A cobalt-catalyzed C(sp2)-H alkoxylation of 1-naphthylamine derivatives has been disclosed, which represents an efficient approach to synthesize aryl ethers with broad functional group tolerance. It is noteworthy that secondary alcohols, such as hexafluoroisopropanol, isopropanol, isobutanol, and isopentanol, were well tolerated under the current catalytic system. Moreover, a series of biologically relevant fluorine-aryl ethers were easily obtained under mild reaction conditions after the removal of the directing group.

Development of 3D printed k-carrageenan-based gummy candies modified by fenugreek gum: Correlating 3D printing performance with sol-gel transition.

Temperature-responsive inks were formulated using k-carrageenan, fenugreek gum (FG), rose extracts, and sugar, of which the first two were used as the gelling agents. The interactions among components in these mixed ink formulations were investigated. Sol-gel transition and rheological properties of these inks were also correlated with extrusion, shape formation, and self (shape)-supporting aspects of 3D printing. Results indicated that incorporating FG increased inks' gelation temperature from 39.7 °C to 44.7-49.6 °C, affecting the selection of printing temperature (e.g., 0 % FG: 40 °C, 0.15 % FG: 45 °C, 0.3 % FG-0.6 % FG: 50 °C). Inks in solution states with lower viscosity (<5 Pa·s) were amenable to ensure their smooth extrusion through the tip of the printing nozzle. A shorter sol-gel transition time (approximately 100 s) during the shape formation stage facilitated the solidification of inks after extrusion. The addition of FG significantly (p<0.05) improved the mechanical properties (elastic modulus, hardness, etc.) of the printed models, which facilitated their self-supporting behavior. Low field nuclear magnetic resonance indicated that the inclusion of FG progressively restricted water mobility, consequently reducing the water syneresis rate of the mixed inks by 0.86 %-3.6 %. FG enhanced hydrogen bonding interactions among the components of these mixed inks, and helped to form a denser network.

A Study of Molecular Dynamic Simulation and Experimental Performance of the Eucommia Ulmoides Gum-Modified Asphalt.

In recent years, eucommia ulmoides gum (EUG), also known as gutta-percha, has been extensively researched. Molecular dynamic simulations and experiments were used together to look at how well gutta-percha and asphalt work together and how gutta-percha-modified asphalt works. To investigate the gutta-percha and asphalt blending systems, the molecular models of asphalt and various dosages of gutta-percha-modified asphalt were set up using Materials Studio (MS), and the solubility parameters, intermolecular interaction energy, diffusion coefficient, and mechanical properties (including elastic modulus, bulk modulus, and shear modulus) of each system were calculated using molecular dynamic simulations at various temperatures. The findings indicate that EUG and asphalt are compatible, and sulfurized eucommia ulmoides gum (SEUG) and asphalt are more compatible than EUG. However, SEUG-modified asphalt has better mechanical properties than EUG, and the best preparation conditions are 10 wt% doping and 1 h of 180 °C shearing. Primarily, physical modifications are required for gutta-percha-modified asphalt.

Surface modification of bacterial cellulose aerogels by ARGET ATRP.

INTRODUCTION: Bacterial cellulose (BC) aerogels have received more and more attention due to their renewability, biodegradability and other excellent properties in recent years. Modification of BC aerogels using different methods would expand their applications. However, many problems exist for these modifications, such as a low grafting ratio, the larger dosage of metal catalyst required and so on. Activator regeneration by electron transfer (ARGET) for atom transfer radical polymerization (ATRP) is a novel ATRP method which could significantly reduce the amount of metal catalyst required and achieve a high grafting ratio. METHODS: Novel nanostructured BC aerogels containing epoxy groups were prepared by the ARGET ATRP method. BC aerogels were functionalized with initiating sites by reaction with 2-bromoisobutyryl bromide (BiBBr), and followed by ARGET ATRP reaction with glycidyl methacrylate (GMA) which was catalyzed by copper(II) bromide (CuBr2) and N,N,N',N,'N"-pentamethyldiethylenetriamine (PMDETA), and then reduced by vitamin C. BC aerogels containing epoxy groups (BC-g-PGMA) were obtained after freeze-drying. The influence factors of the solvent ratio of N,N-dimethyl formamide (DMF)/toluene, monomer concentration, the concentration of CuBr2, the molar ratio of vitamin C (Vc)/CuBr2,reaction temperature and time on the grafting ratio were investigated. RESULTS: The results showed that the optimal DMF and toluene volume ratio was 2:1, the optimal monomer and CuBr2 concentration were 2 mol/l and 1.5 mmol/l. The optimal molar ratio of PMDETA/CuBr2 and Vc/CuBr2 were 4:1 and 1:1. The optimal reaction temperature and time were 60°C and 9 h. Scanning electron microscopy (SEM) images showed that GMA was strongly adhered onto the surface and inside of the BC pellicle. CONCLUSIONS: GMA was self-grown on the BC surface and achieved the high grafting ratio of 1052.7% under optimal conditions. The BC-g-PGMA aerogels containing the epoxy groups will provide wider application prospects in drug release, enzyme fixed, functional materials and other fields.