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Micro pin fin arrays have been widely used in electronic cooling, micro reactors, catalyst support, and wettability modification and so on, and a facile way to produce better micro pin fin arrays is demanded. Herein, a simple electrochemical method has been developed to fabricate copper vertical micro dendrite fin arrays (Cu-VMDFA) with controllable shapes, number density and height. High copper sulphate concentration is one key point to make the dendrite stand vertically. Besides, the applied current should rise at an appropriate rate to ensure the copper dendrite can grow vertically on its own. The Cu-VMDFA can significantly enhance the heat transfer coefficient by approximately twice compared to the plain copper surface. The Cu-VMDFA may be widely used in boiling heat transfer areas such as nuclear power plants, electronic cooling, heat exchangers, and so on.

The structural, mechanical, dynamical and electronic properties of ternary MAX phase Mo2GeC under high pressure has been investigated by first-principles calculations within the generalized gradient approximation of density functional theory. The structural parameters in the pressure range of 0–50 GPa are presented and it is found that Mo2GeC is much more compressible along the a direction than along the c direction. Moreover, mechanical properties including elastic constants, elastic moduli, Possion’s ratio, Vickers hardness, and Deybe’s temperature are given. We find that C 33 increases rapidly as pressure is increased, which implies a strong resistance to the compression strain along the c direction. This mechanical anisotropy is also illustrated by the directional bulk modulus. Furthermore, Mo2GeC is dynamically stable from 0 to 50 GPa by the phonon calculation. Finally our electronic structure calculation shows that Mo2GeC is predicted to be metallic and the metallicity of Mo2GeC increases with increasing pressure. The charge density distributions show the existence of the covalent Mo C bonds and with increasing pressure, the covalent Mo Ge bonds and the covalent Mo-Mo bonds. Bader’s charge analysis shows that the Mo charges increase while the Ge and C charges decrease as pressure is increased.

// Chien-Hung Chen 1 , Chuan-Mo Lee 1 , Hsueh-Chou Lai 2 , Tsung-Hui Hu 1 , Wen-Pang Su 2 , Sheng-Nan Lu 1 , Chia-Hsin Lin 2 , Chao-Hung Hung 1 , Jing-Houng Wang 1 , Mei-Hsuan Lee 3 and Cheng-Yuan Peng 2, 4 1 Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan 2 Division of Hepatogastroenterology, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan 3 Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan 4 School of Medicine, China Medical University, Taichung, Taiwan Correspondence to: Cheng-Yuan Peng, email: cypeng@mail.cmuh.org.tw Keywords: nucleos(t)ide analog, hepatocellular carcinoma, risk score, platelet, alpha-fetoprotein Received: June 01, 2017 Accepted: August 28, 2017 Published: September 28, 2017 ABSTRACT Background: Until now, no risk score could predict hepatocellular carcinoma (HCC) in nucleos(t)ide analog (NA)-treated Asian patients. Methods: We enrolled 1325 NA-naive chronic hepatitis B patients with entecavir monotherapy for >12 months, with 883 and 442 patients randomly assigned to the development and validation groups, respectively, in the risk model. Results: The cumulative probabilities of HCC were 2.4%, 4.1%, and 9.9% after 2, 3, and 5 years of treatment, respectively. In the development group, age, platelet counts, and alpha-fetoprotein levels after 12 months of treatment were the independent predictors of HCC. We converted the Cox proportional hazards regression coefficients for these predictors into risk scores and developed the APA-B model, with the total risk scores ranging from 0 to 15. The risk scores accurately categorized patients with low (0–5), medium (6–9), and high (10–15) risks in the validation group ( P

Janus effect has been studied for emerging materials like Janus membranes, Janus nanoparticles, etc., and the applications including fog collection, oil/water separation, CO 2 removal and stabilization of multiphasic mixtures. However, the Janus effect on oil/water separation is still unclear. Herein, Janus Cu mesh decorated with Ni-NiO/Ni(OH) 2 core-shell nanoparticles is synthesized via selective electrodeposition, in which we keep one side of Cu mesh (Janus A) to be superhydrophilic, while manipulate the wettability of another side (Janus B) from hydrophobic to superhydrophilic. Experimental results indicate that Cu mesh with both-side superhydrophilic shows the superior oil/water separation performance (separation efficiency >99.5%), which is mainly due to its higher water capture percentage as well as larger oil intrusion pressure. Further, we demonstrate the orientation of Janus membranes for oil/water separation, and summarize that the wettability of the upper surface plays a more important role than the lower surface to achieve remarkable performance. Our work provides a clear insight of Janus effect on oil/water separation, it is significative to design high-performance membranes for oil/water separation and many other applications.

Nowadays, new emerging two-dimensional (2D) materials have become a hot topic in the field of theoretical physics, material science, and nanotechnology engineering due to their high surface area, planar structure, and quantum confinement effect. Within a two-dimensional framework, we systematically concentrate on the buckled and puckered systems consisting of the VA group elements (denoted as arsenene, antimonene, and bismuthene). Among these studied systems, the buckled antimonene harbors a thermoelectric figure of merit (ZT) of 2.15 at room temperature. This is probably the highest value that has ever been reported in pristine 2D materials. By simple biaxial strain engineering, the ZT can even get enhanced to 2.9 under 3% tensile strain. The enhancement mainly results from both tuning the electronic structures and reducing the thermal conductance. This work predicts a new promising candidate in thermoelectric devices, based on the fact that buckled antimonene has been lately fabricated and proved to be ...

Accumulative evidence has shown the adverse effects of a geomagnetic field shielded condition, so called a hypomagnetic field (HMF), on the metabolic processes and oxidative stress in animals and cells. However, the underlying mechanism remains unclear. In this study, we evaluate the role of HMF on the regulation of cellular reactive oxygen species (ROS) in human neuroblastoma SH-SY5Y cells. We found that HMF exposure led to ROS decrease, and that restoring the decrease by additional H2O2 rescued the HMF-enhanced cell proliferation. The measurements on ROS related indexes, including total anti-oxidant capacity, H2O2 and superoxide anion levels, and superoxide dismutase (SOD) activity and expression, indicated that the HMF reduced H2O2 production and inhibited the activity of CuZn-SOD. Moreover, the HMF accelerated the denaturation of CuZn-SOD as well as enhanced aggregation of CuZn-SOD protein, in vitro. Our findings indicate that CuZn-SOD is able to response to the HMF stress and suggest it a mediator of the HMF effect. Electronic supplementary material The online version of this article (doi:10.1007/s13238-017-0403-9) contains supplementary material, which is available to authorized users.

Recently, oil/water separation has attracted intensive attention because of frequent crude oil spill accidents and the increasing amount of industrial wastewater. Ti-based materials are nontoxic and environment-friendly for oil/water separation; however, there is little attention focused on this field. In the present work, we introduce, for the first time, surface −O–Ti–F groups onto Ti foam by a simple anodization in a fluorine-containing electrolyte to form a superhydrophilic membrane for oil-in-water emulsion separation, which was proven to be excellent with the assistance of surface nanocavities. The water permeability of anodized Ti foam is elevated by about 10 times as compared to that of the original one, and the oil/water separation efficiency is above 99% with good anticorrosive properties. In addition, this fluorine-induced superhydrophilicity can be applied to metals and semimetals for many other applications such as self-cleaning, surface modification of catalysts, removal of heavy metal ions,...

The study of inverse heat transfer problems (IHTPs) have obtained extensive attention over the recent decades. However, IHTPs are often mathematically ill-posed, namely the solution stability suffers from measurement errors. Although there already exist established methods for IHTPs, their applications are mostly limited to simple geometric configurations in one- or multi-dimensions due to the high complexity. It is still a crucial task to develop special solution techniques that can ensure fast and accurate estimation. Recently, we developed a forward modeling approach and a time-space adaptive mesh refinement (TSAMR) strategy. In this work, we consider a realistic simulation study and use these methods to reconstruct laser heating boundary condition on the front surface of a 3D object subjected to laser beam heating and a combined radiation. By conducting groups of parameters tests, the solution quality is expected to be improved. The estimated heat-flux distributions and temperature distributions are presented to validate the proposed methods. Based on these results, a very large number of tests are supposed to be performed in the supercomputing plat-form in future work to obtain optimal parameters for the TSAMR strategy, so as to solve complicated IHTPs in a more efficient and accurate manner.

In recent years, another two-dimensional (2D) family, monolayer metal monochalcogenides (group IIIA–VIA), has attracted extensive attention. In this work, we adopt density functional theory (DFT) and the non-equilibrium Green's function (NEGF) method to systematically investigate the ballistic thermoelectric properties of the IIIA–VIA family, including GaS, GaSe, GaTe, InS, InSe, and InTe. Among others, the InTe monolayer possesses the highest figure of merit, ZT = 2.03 at 300 K, due to its ultra-low thermal conductance. Biaxial strain in the range of −10% (compressive) to 10% (tensile) is applied to the InTe monolayer and the strain-induced electronic and thermal transport properties are discussed. The maximum ZT (up to 2.7) for the InTe monolayer at 300 K is achieved under an 8% tensile strain.

Background Acral melanoma (AM) is the most common histopathological subtype of malignant melanoma in Asians. However, differences in the mutational profiles underlying AM and nonacral cutaneous melanoma (NAM) in Asians are not well understood. Objectives To augment the understanding of the prevalence, patterns and associations of various mutations between different subtypes of melanoma. Methods We performed comprehensive genomic profiling of 409 cancer-associated genes, using next-generation sequencing, in 66 primary melanomas comprised of 45 AMs and 21 NAMs. Results Most of the AMs (n = 27/45; 60%), but only five of 21 (24%) NAMs, were triple wild-type (triple-WT) tumours. Compared with AMs, NAMs exhibited a significantly higher frequency of BRAF mutations. The frequencies of NRAS/KRAS mutations, cell-cycle aberrations, copy number gains in BIRC2, BIRC3 and BIRC5, and gains of receptor tyrosine kinase genes were significantly higher in AMs. Ulceration was found at significantly higher rates in the AMs and NAMs with cell-cycle aberrations and gains of receptor tyrosine kinase genes. Notably, cell-cycle aberrations and copy number gains in BIRC2, BIRC3 and BIRC5 were significantly associated with poor melanoma-specific survival in the 66 patients with melanoma and especially in the 45 patients with AM. Multivariate analysis showed that lymph node metastasis and cell-cycle aberrations were independent prognostic factors of melanoma-specific survival. Conclusions This study strengthens our understanding of the patterns and clinical associations of oncogenic mutations in AMs and NAMs in Asians. What's already known about this topic? Mutation frequencies of driver genes vary between melanoma subtypes. Acral melanoma is the most common subtype of melanoma in Asians. KIT mutations and copy number variations occur more frequently in the acral subtype of melanoma than in the nonacral subtype What does this study add? NRAS/KRAS mutations, cell-cycle aberrations, copy number gains in BIRC2, BIRC3 and BIRC5, and amplifications of receptor tyrosine kinase genes were significantly enriched in acral melanoma and could be potential targets for treatment. Melanomas with cell-cycle aberrations and gains in receptor tyrosine kinase genes were significantly more likely to contain ulceration. What is the translational message? Cell-cycle aberrations and copy number gains in BIRC2, BIRC3 and BIRC5 were significantly associated with poor melanoma-specific survival. These observations should be explored further for future drug development.

Boiling heat transfer is one of the most effective methods to meet the challenge of heat dissipation of high heat flux devices. A wetting hybrid surface has been shown to have better performance than the hydrophilic or hydrophobic surface. This kind of wetting hybrid modification is always carried out on a plain or flat surface. In this paper, polytetrafluoroethylene (PTFE) powders were coated on a superhydrophilic microcopper dendrite fin surface to build a wetting hybrid surface. The pool-boiling experimental results showed that after applying the coating, the wall superheat dramatically decreased to 8 K, which is 9 K lower than that on the original surface at 250 W·cm−2, and has a better performance than a silicon pin-fin-based wetting hybrid surface.

A MnCO₃ /Multiwalled carbon nanotube (MnCO₃/MWCNT) composite has been successfully fabricated by an in-suit hydrothermal method. When the MnCO₃/MWCNT composite is applied as anode materials in lithium-ion batteries (LIBs), the electrodes exhibit a reversible capacity of 645 mA h g

Small bubbles are desirable to be frequently generated and detach from the heated surface in pool boiling. Bubble nucleation and bubble departure can be influenced by the size of micro-nano structure. In this work, four honeycomb micro-nano porous copper surfaces with successively increasing pore sizes are prepared by controlling the electrodeposition current densities. Both experiments on saturated pool boiling of water and numerical simulations are conducted. The heat transfer performance of prepared surfaces is improved significantly and then decreased slightly when the pore size ranges from 48 μm to 128 μm, with maximum critical heat flux and heat transfer coefficient reaching 187.3 W/cm2 and 23.7 W/cm2/K, respectively. Numerical simulations considering three-dimensional (3D) complex geometries of the four samples reconstructed by a computed tomography scanning technique are conducted. Numerical results show that the percentage of heat flowing out of the three-phase contact lines by phase change at high heat-flux supply can increase to 90%, which is consistent with previous literature results. Subject to a parametric 3D transient heat-conduction forward model developed in this work, a multi-layer end-to-end convolutional neural network is for the first time constructed and trained to solve the corresponding ill-posed inverse problems of 3D transient heat conduction efficiently. It provides a promising alternative way to develop a highly efficient temperature-to-heat-flux soft sensor technique for both boiling applications and many other similar engineering problems.