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Diamond has an extremely high thermal conductivity, making it to have a great potential as a heat dissipation material. Based on the hot filament chemical vapor deposition (HFCVD) technique, diamond thick films were deposited on silicon carbide substrates by using the multi-step method in this paper. The scanning electron microscopy (SEM) and Raman spectroscopy were adopted for characterizing the samples. The influences of filament power, carbon concentration, and reactive pressure on the growth rate and quality of the diamond films were systematically studied. It is found that the diamond film with the best quality is synthesized by adopting a filament power of 1 600 W, a methane/hydrogen flux ratio of 18/300 (nucleation stage) and 14/300 (growth stage), and a reactive pressure of 4 kPa. The corresponding growth rate is 1.4 μm/h.

Isolation of circulating tumor cells (CTCs) from blood samples has important prognostic and therapeutic implications for cancer treatments, but the process is very challenging due to the low concentration of CTCs. In this study, we report a novel 3D printed microfluidic device functionalized with anti-EpCAM (epithelial cell adhesion molecule) antibodies to isolate CTCs from human blood samples. A 3D printing technology was utilized with specially designed interior structures to fabricate a microfluidic device with high surface area and fluid flow manipulation, increasing capture efficiency of tumor cells. These devices with the optimal flow rate (1 mL/h) and channel length (2 cm) were demonstrated to test three kinds of EpCAM positive cancer cell lines (MCF-7 breast cancer, SW480 colon cancer, and PC3 prostate cancer), and one kind of EpCAM negative cancer cell line (293T kidney cancer). Experimentally, the capture efficiency higher than 90% has been achieved, and the isolation of MCF-7 tumor cells from spiked human blood samples has also been demonstrated. Combined with DNA-based detection (e.g. polymerase chain reaction or DNA sequencing), the detection and analysis of released DNAs from captured tumor cells could be another future direction for clinical diagnosis and cancer treatment.

Heterogeneous catalysts for parahydrogen-induced polarization (HET-PHIP) would be useful for producing highly sensitive contrasting agents for magnetic resonance imaging (MRI) in the liquid phase, as they can be removed by simple filtration. Although homogeneous hydrogenation catalysts are highly efficient for PHIP, their sensitivity decreases when anchored on porous supports due to slow substrate diffusion to the active sites and rapid depolarization within the channels. To address this challenge, we explored 2D metal-organic layers (MOLs) as supports for active Rh complexes with diverse phosphine ligands and tunable hydrogenation activities, taking advantage of the accessible active sites and chemical adaptability of the MOLs. By adjusting the electronic properties of phosphines, TPP-MOL-Rh-dppb (TPP = tris(4-carboxylphenyl)phosphine), featuring a κ 2-connected di(phosphine) ligand, generated hyperpolarized styrene achieving an over-2400-fold signal enhancement and a polarization level of 20% for 1H in methanol- d 4 solution. The TPP-MOL-Rh-dppb effectively inherited the high efficiency and pairwise addition of its homogenous catalyst while maintaining the heterogeneity of MOLs. This work demonstrates the potential of 2D phosphine-functionalized MOLs as heterogeneous solid support for HET-PHIP. [ABSTRACT FROM AUTHOR]

LIF maintains self‐renewal growth in mouse embryonic stem cells (mESC) by activating STAT3, which translocates into nucleus for pluripotent gene induction. However, the ERK signaling pathway activated by LIF at large counteract with pluripotent gene induction during self‐renewal growth. Here, it is reported that in mESC STAT3 undergoes multivesicular endosomes (MVEs) translocation and subsequent secretion, LIF‐activated STAT3 is acetylated on K177/180 and phosphorylated on Y293 residues within the N‐terminal coiled‐coil domain, which is responsible for the interaction between STAT3 and Secl5b, an exocyst complex component 6B (EXOC6B). STAT3 translocation into MVEs resulted in the downregulation of T202/Y204‐ERK1/2 phosphorylation and up‐regulation of S9‐GSK3β phosphorylation for maintaining mESC self‐renewal growth. STAT3 with K177R/K180R or Y293F substitution fails to execute MVEs translocation and Secl5b‐dependent secretion. Mice expressing K177RK180R substitution (STAT3mut/mut) are partially embryonic lethal. In STAT3mut/mut embryos, gene expressions related to hematological system function changed significantly and those living ones carry a series of abnormalities in the hematopoietic system. Furthermore, mice with Secl5b knockout exhibit embryonic lethality. Thus, Secl5b mediated STAT3 MVEs translocation regulates the balance of ERK and GSK3β signaling pathways and maintain mESC self‐renewal growth, which is involved in regulating the stability of hematopoietic system. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Electrochemical attenuated total reflection surface‐enhanced infrared absorption spectroscopy (ATR‐SEIRAS) plays an important role in deciphering interfacial reaction mechanisms at molecular level. However, the corrosive etching of Si internal reflection element by OH− largely impedes reliable SEIRAS measurements in strong alkaline electrolytes. Herein, a dense and chemically inert nanocrystalline diamond (NCD) film is successfully fabricated at a thickness of ~120 nm through hot filament chemical vapor deposition on a micromachined Si wafer to insulate the OH− etching. A reversible interfacial water feature without spectral interference of Si‐O band is obtained in 1.0 mol·L–1 KOH on Au/NCD/Si film electrode. Afterwards, electrochemical CO reduction reaction on Cu film electrode is explored in different KOH concentrations ranging from 0.1 to 3.0 mol·L–1 as a model reaction. A redshift of COL band, as well as its lower intensity but faster depletion kinetics, is noted with increasing electrolyte pH, whereas COB is identified as an inert spectator accumulating on Cu surface. Our present work demonstrates the alkaline resistant feature of diamond/Si composite internal reflection element, which could be a powerful platform to study electrocatalytic reactions in strong alkaline media. [ABSTRACT FROM AUTHOR]

Purpose: This study assesses the diluted Schirmer method's effectiveness in collecting tears from dry eye syndrome patients, aiming to identify the most suitable tear collection technique for them. Methods: A prospective study. Tear samples were collected from patients with dry eye syndrome and healthy individuals using two methods: (1) Direct Schirmer Method: Schirmer strips were directly inserted into the eye to collect tears. (2) Diluted Schirmer Method: After instilling physiological saline into the eye and waiting for 30 s to ensure thorough mixing with tears, Schirmer strips were used for collection. Tear samples from both groups were analyzed and compared for total protein and cytokine levels (IL-1β, IL-6, IL-8, TNF-α). Results: (1) The study included 32 participants: 16 with dry eye syndrome (4 males, 12 females, average age 34.92 ± 10.13 years) and 16 healthy controls (5 males, 11 females, average age 32.25 ± 9.87 years). (2) The diluted Schirmer method produced a significantly larger tear volume compared to the direct method (p < 0.05), with lower Visual Analogue Scale (VAS) scores indicating less discomfort (p < 0.05). (3) The average total protein content of the two groups was 51.70 ± 3.166 ng measured by Direct Schirmer method, and the average total protein content of the Diluted Schirmer method was 50.05 ± 3.263 ng. There was no statistical difference between the two groups. (t = 1.051, p = 0.3098) (4) The concentrations of total tear protein and various cytokines measured by both methods were higher in the dry eye group compared to the normal group, with statistically significant differences (p < 0.05). Both methods reflected consistent changes in tear protein profiles. Conclusion: The diluted Schirmer method can comfortably collect an adequate volume of tear samples in a short time and consistently reflect changes in tear proteins, making it an effective method for tear collection in patients with dry eye syndrome. [ABSTRACT FROM AUTHOR]