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• Parallel microgrooves are fabricated on the bottom of five parallel microchannels (W=200 µm, H=250 µm, L=10 mm) to enhance the boiling heat transfer without sacrificing pressure drop. • A highly desirable periodic rewetting mechanism was observed to substantially delay CHF conditions and enhance heat transfer rates. • Compared to plain-wall microchannels, HTC is enhanced up to ~50% at a mass flux of 303 kg/m2s due to the sustainable thin film evaporation. Moreover, CHF is substantially enhanced by ~155% at a mass flux of 389 kg/m2s due to the rapid and periodic rewetting enabled by these decorated microgrooves. • The enhancement in nucleate boiling was investigated under heat pulse with heating period of 0.5 s. Flow boiling in microchannels is one of the most desirable cooling solutions for high power electronics. However, it is challenging to promote the flow boiling performance, particularly critical heat flux (CHF), due to their unfavorable liquid rewetting. Inlet restrictors (IRs) have been successfully used to manage two-phase instabilities in flow boiling in microchannels. However, IRs would result in extremely high pressure drop. In this study, without using IRs, parallel microgrooves (W=50 µm, H=250 µm, L=10 mm) are fabricated on the bottom surface of five parallel microchannels (W=200 µm, H=250 µm, L=10 mm) to effectively manage two-phase flow instabilities without sacrificing pressure drop. Our visualization study shows that these microgrooves can enable rewetting at highhigh frequencies up to 151 Hz and enhance thin film evaporation with the highest thin film ratio of 0.65. A highly desirable periodic rewetting mechanism can substantially delay CHF conditions and enhance heat transfer rates. Flow boiling in the present microchannel configuration has been systematically characterized with mass flux ranging from 100 kg/m2s to 600 kg/m2s. Compared to plain-wall microchannels, flow boiling heat transfer coefficient (HTC) is enhanced up to ~72% at a mass flux of 210 kg/m2s due to the sustainable thin film evaporation. Moreover, CHF is substantially enhanced by ~155% at a mass flux of 389 kg/m2s due to the rapid and periodic rewetting enabled by these decorated microgrooves. We also observed that the enhancement of HTC fades when mass flux exceeds 346 kg/m2s due to flooding. [ABSTRACT FROM AUTHOR]

This study employs first-principles calculation to investigate the MoSi 2 N 4 /SiC heterojunction. It aims to determine the structure, electronic, and optical properties of the heterojunction and assess the impact of varying vertical electric fields and biaxial strains on these properties. The results show that the MoSi 2 N 4 /SiC heterojunction is a direct bandgap semiconductor, exhibiting a band gap of 0.31 eV. This heterojunction benefits from a built-in electric field originating from the SiC layer and extending to the MoSi 2 N 4 layer. The optical absorption peaks in the ultraviolet region are significantly more intense than those in MoSi 2 N 4 and SiC monolayers, particularly at a wavelength of 172 nm, where the intensity reaches 1.99 × 106 cm−1. The study also shows that an increasing positive vertical electric field leads to a rising band gap. On the other hand, increasing tensile or compressive strain causes a gradual decline in the band gap. Specifically, at a strain of −8 %, the absorption peak intensity reaches 3.4 × 106 cm−1 at 172 nm, and the absorption spectrum broadens to 722 nm at an 8 % strain. In conclusion, the MoSi 2 N 4 /SiC heterojunction shows promise for enhancing the optical properties of two-dimensional materials and offers valuable insights for the development of efficient new ultraviolet devices. [ABSTRACT FROM AUTHOR]

Highlights • Five parallel microchannels are interconnected by micro-slots. • Micro-slots can enable high frequency nucleate boiling. • Highly coordinated, rapid and sustainable nucleate boiling are realized. • The HTC and CHF are significantly enhanced on the present design. • The enhancements of HTC and CHF are ∼175% and ∼76%, respectively. Abstract Flow boiling in microchannels using dielectric fluids is one of the most desirable cooling solutions for high power electronics. However, it is challenging to promote the flow boiling performances, particularly critical heat flux (CHF), due to their unfavorable thermophysical properties. Flow boiling in parallel and isolated microchannels has been extensively studied. In this study, five parallel microchannels (W = 200 µm, H = 250 µm, L = 10 mm) are interconnected by 4 × 28 micro-slots (20 µm wide and 250 µm deep) starting from the middle section to the channel outlet. Our visualization study shows that these micro-slots designed as artificial nucleation sites can enable high frequency nucleate boiling by drastically reducing the bubble waiting time and remaining fully activated, simultaneously. More importantly, such rapid switch on–off harmonically coordinated nucleate boiling in the neighboring channels creates a highly desirable periodic rewetting mechanism to substantially delay CHF conditions and enhance heat transfer rate. Flow boiling in this innovative microchannel configuration has been systematically characterized with mass flux ranging from 462 kg/m2∙s to 1617 kg/m2∙s. Compared to plain-wall microchannels with inlet restrictors (IRs), flow boiling heat transfer coefficient (HTC) is enhanced up to ∼172% at a mass flux of 462 kg/m2·s primarily owing to the enhanced latent heat transfer including nucleate boiling and thin film evaporation. The peak value of effective HTC is ~60 kW/m2·K in the fully developed boiling regime. Moreover, CHF is substantially enhanced by ∼76% at a mass flux of 1155 kg/m2·s owing to the rapid and periodic rewetting enabled by these micro-slots. Such drastic enhancements have been achieved without compromising two-phase pressure drop. [ABSTRACT FROM AUTHOR]

MiR-16-5p, a member of the miR-16 family, has been reported to be abnormal expression in tumor tissues and blood of tumor patients, and also downregulated in most cancer cell lines. Aberrant expression of miR-16-5p promotes tumor cell proliferation, invasion, metastasis, angiogenesis, and can also affect the treatment sensitivity, such as radiotherapy and chemotherapy. Generally, miR-16-5p plays an anti-tumor role and these diverse functions of miR-16-5p in tumors collectively indicate that miR-16-5p may become an attractive target for novel anticancer therapies and a powerful diagnostic and prognostic biomarker for early tumor detection and population risk screening. Herein we review the role and utilization of miR-16-5p in malignant tumor in detail. [Display omitted] • MiR-16-5p is abnormally expressed in tumor bulk, blood and cell lines. • MiR-16-5p plays an anti-cancer role in most malignant solid tumors. • MiR-16-5p is a powerful diagnostic and prognostic biomarker for malignant solid tumors. [ABSTRACT FROM AUTHOR]

Ultra-high-speed laser cladding (UHSLC) not only offers an efficient solution to the limitations of conventional laser cladding but also aligns with the contemporary objectives of material conservation and efficiency enhancement in metal protective coatings. This study investigates the fabrication of CrFeCoNiMo 0.2 high-entropy alloy (HEA) coatings using UHSLC and traditional laser cladding (TLC) methods. Key aspects such as macroscopic forming quality, element distribution, dilution rate, grain morphology, hardness, and electrochemical corrosion properties of both UHSLC and TLC coatings are thoroughly examined. Notably, UHSLC-produced coatings, with their significantly reduced thickness ranging from 100 to 300 μm, demonstrate an impressively low substrate dilution rate compared to the 2–3 mm thickness of TLC coatings. The rapid solidification inherent in UHSLC leads to smaller grain sizes in the coating, resulting in enhanced hardness. Moreover, the UHSLC coating exhibits superior corrosion resistance, characterized by a lower maintaining-passivity current density in 1 mol/L H 2 SO 4 and a higher self-corrosion potential relative to TLC coatings. This work presents a novel approach, employing high-efficiency and low-cost laser-cladding technology, to minimize dilution in the matrix and improve the coating properties of HEAs. • There are no macroscopic and microscopic defects in HEAs prepared by UHSLC. • Uniform distribution of elements in ultra-thin coating of CrFeCoNiMo 0.2 HEA. • The CrFeCoNiMo 0.2 HEA nanocrystalline coating was synthesized by UHSLC. • Nanocrystalline CrFeCoNiMo 0.2 HEA coating exhibit excellent corrosion resistance. [ABSTRACT FROM AUTHOR]

A new type of ternary monocarbides M 0.5 Re 0.5 C (M = V, Nb, Ta) with outstanding mechanical properties were firstly reported by introducing the Re into their well-known hard parent compounds M C to tune the valence electron concentration (VEC). By an efficient structure searching method, a universal orthorhombic structure with space group of Cmc 2 1 has been uncovered and demonstrated to be the ground-state phase of these three monocarbides, which can be sustained up to the ultrahigh pressure of 300 GPa for V 0.5 Re 0.5 C and Nb 0.5 Re 0.5 C. The thermodynamic and dynamical stabilities of the predicted phases were confirmed by the formation enthalpy and phonon spectra calculations. The structural, mechanical as well as electronic properties of M 0.5 Re 0.5 C in comparison with their parent compounds M C were thus fully investigated using first-principles density functional theory (DFT) calculations. Compared to their parent compounds M C, results on the mechanical calculations indicated that they not only possess larger Vickers hardness and ideal indentation shear strength values but also exhibit much smaller elastic and ideal strength anisotropy which are advantageous to their potential applications. Detailed analysis of electronic structures reveals that the origin of the improved mechanical properties of M 0.5 Re 0.5 C is mainly attributed to the enhanced hybridization of metals- d and C-2 p orbitals by locating the fermi level at the valley of the pseudogap. [ABSTRACT FROM AUTHOR]

The interfacial interactions between as-grown graphene (G) and its metal substrates play a crucial role in large-scale graphene transfer and governing anticorrosion properties. However, few studies have been conducted on quantifying the adhesion energy of as-grown graphene, especially, in systems such as nickel/graphene (Ni/G) with strong interfacial interactions. In this study, for the first time, a novel full-field three dimensional (3D) blister test via stereo-digital image correlation (StereoDIC) was developed to characterize the interfacial interaction between as-grown graphene on nickel (Ni) and copper (Cu) substrates, respectively. To minimize effects of surface roughness and residue stress on adhesion energy, the graphene growth processes on both Cu and Ni substrates were carefully controlled to assure nearly identical growth processes in terms of temperature, growth time, heating and cooling rates. The adhesion energy of as-grown graphene on Ni was measured to be 6.775 ± 0.556 J m − 2 , which is more than 7 times higher than that of as-grown graphene on Cu. Instead of van der Waals bonds, the Ni/G interface exhibited adhesion that is close to covalent bonding. We believe that this full-field 3D blister test could be further extended for evaluating strong interfacial interactions between graphene and other metal substrates. Image 1 [ABSTRACT FROM AUTHOR]

This study aimed to build a mathematical model of physiologically based pharmacokinetic combined DPP-4 occupancy (PBPK-DO) in humans to provide some recommendations for dosing adjustment in patients with renal impairment. The PBPK-DO model was built using physicochemical and biochemical properties and binding kinetics data of TRE and OMA, and then validated by the clinically observed pharmacokinetics (PK) and pharmacodynamics (PD). Finally, the model was applied to determine dose adjustment in patients with renal impairment. The predicted PK and DPP-4 occupancy matched well with the clinically observed data, and all absolute average-folding errors (AAFEs) were within 2. The simulations showed that TRE and OMA were both suggested to only support dose reduction by half in patients with severe renal impairment based on this PBPK-DO model, which is different from the commendations only in terms of their AUC 0–336 changes. These simulation results were in good agreement with clinical recommendations about dosage adjustment in patients. The present PBPK-DO model can simultaneously predict PK and PD of TRE and OMA in humans and also provide valuable recommendations for dosing adjustment in renal impairment patients, which cannot be achieved by alone depending on PK change. [Display omitted] • A new PBPK-DO simulation model can predict PK and PD profiles of trelagliptin and omarigliptin simultaneously in healthy humans. • The PBPK-DO simulation model can predict the PK and PD profiles of trelagliptin and omarigliptin in patients with renal impairment. • The PBPK-DO simulation model can provide more valuable recommendation about dosing adjustment in patient with renal impairment. [ABSTRACT FROM AUTHOR]

• Alternating Nucleate Boiling of water is examined in this study. • The HTC and CHF are significantly enhanced on the present design. • The enhancements of HTC and CHF are without escalating pressure drop. • HTC and CHF can be substantially enhanced up to 111% and 24%. • A CHF value of 810 W/cm2 is achieved at a moderate mass flux of 430 kg/m2∙s. Flow boiling in parallel and isolated microchannels has been extensively studied. In this study, five parallel microchannels (W = 200 µm, H = 250 µm, L = 10 mm) are interconnected by 28 micro-slots (20 µm wide and 250 µm deep) starting from the outlet. These micro-slots serve as nucleation sites to greatly enhance nucleate boiling. More importantly, the alternating and enhanced nucleate boiling in neighboring microchannels can generate additional pressure drop during the bubble growth-departure cycle and hence enable highly desirable periodic rewetting inside channels, particularly near outlet regions. This new microchannel configuration can substantially enhance nucleate boiling during flow boiling processes. Coupling with the enhanced nucleate boiling and the induced thin film evaporation, heat transfer coefficient (HTC) in present microchannel configuration can be enhanced up to ~107.6% at mass flux 250 kg/m2∙s with a ~17% higher critical heat flux (CHF) compared to the plain-wall microchannels with inlet restrictors (IRs). In addition, we achieve a CHF value of 810 W/cm2 at a moderate mass flux of 430 kg/m2∙s. All these enhancements are realized without compromising two-phase pressure drop compared to plain wall microchannels with inlet restrictors (IRs). Two-phase flow instabilities in terms of temperature and pressure drop fluctuations are also significantly suppressed. [ABSTRACT FROM AUTHOR]