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A shielded geomagnetic field, also called the hypomagnetic field (HMF), interferes with the metabolic processes of various cells and animals exhibiting diverse effects in different models, however, its underlying mechanism remains largely unknown. In this study, we assessed the effect on the energy metabolism of SH-SY5Y cells in HMF and found that HMF-induced cell proliferation depends on glucose supply. HMF promoted SH-SY5Y cell proliferation by increasing glucose consumption rate via up-regulating anaerobic glycolysis in the cells. Increased activity of LDH, a key member of glycolysis, was possibly a direct response to HMF-induced cell proliferation. Thus, we unveiled a novel subcellular mechanism underlying the HMF-induced cellular response: the up-regulation of anaerobic glycolysis and repression of oxidative stress shifted cellular metabolism more towards the Warburg effect commonly observed in cancer metabolism. We suggest that cellular metabolic profiles of various cell types may determine HMF-induced cellular effects, and a magnetic field can be applied as a non-invasive regulator of cell metabolism.

The research on graphene-based anode materials for high-performance lithium-ion batteries (LIBs) has been prevalent in recent years. In the present work, carbon-coated SnO2 riveted on a reduced graphene oxide sheet composite (C@SnO2/RGO) was fabricated using GO solution, SnCl4, and glucose via a hydrothermal method after heat treatment. When the composite was exploited as an anode material for LIBs, the electrodes were found to exhibit a stable reversible discharge capacity of 843 mA h g−1 at 100 mA g−1 after 100 cycles with 99.5% coulombic efficiency (CE), and a specific capacity of 485 mA h g−1 at 1000 mA g−1 after 200 cycles; these values were higher than those for a sample without glucose (SnO2/RGO) and a pure SnO2 sample. The favourable electrochemical performances of the C@SnO2/RGO electrodes may be attributed to the special double-carbon structure of the composite, which can effectively suppress the volume expansion of SnO2 nanoparticles and facilitate the transfer rates of Li+ and electrons during the charge/discharge process.

Surface micro/nano processing is an important method and research hotspot for enhancing the boiling heat transfer process. However, the effects of a structural gradient on a boiling surface have not been systematically studied. In this paper, we review researches that focus on porous surfaces with a structural gradient and their effects on the enhancement of boiling heat transfer and performance of phase-change devices from two main aspects: Geometric gradient and wettability gradient. Porous surfaces with a geometric (structural) gradient were divided into four series: single-layer geometric gradient structure, multi-layer geometric gradient structure, surface covered with a micro/nanolayer, and surface with a radial gradient. In addition, the surface with a wettability gradient also has a considerable improvement in boiling heat transfer. Especially, we present some of the work related to the improvement in boiling heat transfer for porous surfaces with structural gradient, which has been carried out by our research group. Honeycomb-like and forest-like porous copper surfaces are typical single-layer geometric gradient porous surfaces with excellent boiling heat transfer performance. They have abundant microstructures and sub-microstructures/nanostructures, which are favorable for vapor escaping and liquid rewetting, respectively. For all the mentioned single-layer geometry gradient porous surfaces, the critical heat flux increases as the sample thickness increases. Furthermore, we fabricated a two-layer composite porous surface (TLCS) with a honeycomb-like porous copper surface on top of a forest-like porous copper surface. This TLCS is a multilayer geometric gradient structure porous surface that can further enhance the boiling heat transfer process. The heat transfer coefficient (HTC) of TLCS is 1.5 and 1.2 times larger than those of the biomimetic copper forest and honeycomb structures, respectively. When a small current is applied to the honeycomb-like porous copper surface, the dendrites on the pore wall transferred to micro balls and a surface with a structural gradient is obtained. The modified surface is a microstructural porous surface covered by a nanolayer that further enhances the HTC (1.7 times). The diameter of the honeycomb-like porous copper surface can be controlled with a radial diameter gradient. A sample in which the diameter around the center is much smaller than that around the edge enhances the HTC 1.4 times compared with a sample with uniform diameter. When the TLCS was modified with polytetrafluoroethylene (PTFE), it became a hybrid wetting surface. The experimental results show that the wall superheat temperature at the same heat flux during the heat flux decreasing can repeat that during the heat flux increasing well within 0.5°C, demonstrating that the boiling hysteresis was successfully eliminated. As the porous surface with a structural gradient has excellent performance in boiling heat transfer, it has been widely used in phase-change devices, such as loop and flat heat pipes, to improve their functioning. An ultra-thin flat heat pipe (UTHP), which is only 0.6 mm thick, can significantly reduce the evaporator temperature by 10°C under a 6 W heat load compared with a copper plate. This paper summarizes the most relevant features related to boiling heat transfer enhancement when using structural-gradient porous surfaces and the improvements in phase-change devices that use such surfaces. Despite the advances in this aspect, the porous surfaces can be further optimized to achieve a better heat transfer performance.

In this paper, the solution methods of three-dimensional transient inverse heat conduction problems (3D IHCP) arising from pool boiling applications that need to reconstruct Neumann boundary conditions are summarized. Due to their mathematical ill-posedness, it is still non-trivial to solve these 3D IHCP at a reasonable cost. Firstly, we introduce the optimization-based regularization methods, such as Tikhonov regularization and iterative regularization. In general, it requires to solve a large number of optimization problems constrained by 3D partial differential equations (PDE). In this case, an improved Tikhonov regularization method is developed to quickly obtain optimal Tikhonov regularization parameter and thereby can accelerate the entire inverse calculation process. Furthermore, an iterative regularization method that is based on the conjugate gradient method is proposed to handle the high-resolution measurement data and many pointwise measurement data. In pool boiling experiments, they can be obtained by an infrared camera and mirco-thermocouples, respectively. Secondly, a completely different approach, a direct two-step strategy is presented to solve the same 3D transient ICHP on thin-plates that commonly occur in engineering applications. The main idea of the approach is to transform the inverse problem into a forward problem that is easier to solve by replacing the unknown Neumann boundary condition with an approximated Dirichlet boundary condition. The method has great advantage in efficiency compared with the optimization-based method that often requires to solve dozens or hundreds of direct, adjoint and sensitivity PDE problems, and therefore has the potential to be developed as efficient online heat-flux soft sensors for many practical applications. Thirdly, to further speed up the numerical solution procedure we develop a time-space dependent adaptive mesh refinement strategy due to the fact that the heat-flux and temperature dynamics related to bubble structures rapidly change in space and time on the boiling surface. A few classical engineering benchmark problems are considered to validate the aforementioned solution approaches, and the proposed approaches are also successfully applied to reconstruct the transient heat-flux distributions on the boiling surface from the noisy experimental data obtained in a series of real pool boiling experiments along the entire boiling curve. On the one hand, the corresponding research works reviewed can be used to explore the heat-transfer mechanism and establish a more accurate heat transfer model enabling the fast, robust and accurate reconstruction of local heat fluxes, which can be considered as realistic boundary conditions on the boiling surface to further study the two-phase flow and heat transfer process of boiling fluid above the heater. On the other hand, it can be also applied to explore the local details of the enhanced pool boiling heat transfer for the design of new heaters such as micro/nano structured surfaces, provide predictions related to the boiling process and conduct optimal experimental design in a systematic way. In the future work, a large number of 3D IHCP for different test regularization parameters will be calculated through a high-throughput parallel computational strategy. Besides, for thick heaters the direct two-step strategy can be used to solve the 3D ICHP accurately with an initial heat-flux guess obtained by the proposed optimization-based inversion approach. This way, the computational efficiency can be further improved. Furthermore, other new inversion methods, for example, which are based on artificial neural network method are being developed to solve 3D transient IHCP for more complex structured heater surfaces such as the micro/nano structures.

In recent years, superhydrophilic and underwater superoleophobic membranes have shown promising results in advanced oil/water separation. However, these membranes still have some drawbacks, like tedious preparation process and instability, which hinder their application in oil/water separation. Accordingly, the development of a facile approach to prepare superhydrophilic membranes with excellent oil/water separation performance is still coveted. Here, a copper mesh decorated with cauliflower-like nickel (Cu mesh@CF-Ni) is synthesized via a facile one-step electrodeposition method. Due to the surface polar -OH and -O-Ni-F groups of the Ni(OH)2/NiO x F y shell of the cauliflower-like nickel (CF-Ni), this Cu mesh@CF-Ni displays superhydrophilic and underwater superoleophobic wettability. The results show that the Cu mesh@CF-Ni has excellent oil/water separation efficiency (higher than 99.2%) and ultrahigh water flux (around 20 L h-1 cm-2). Moreover, it also displays good stability in a 10 wt % NaCl solution and 1 M NaOH solution for oil/water separation. By introducing the CF-Ni with polar Ni(OH)2/NiO x F y components onto the surface of the materials via a simple electrodeposition method, the materials will acquire the capability to not only achieve oil/water separation but also realize many other applications, like self-cleaning, underwater bubble manipulation, and fog harvesting.

Inverse heat conduction problems appear in a variety of applications in industry and academia. Due to their mathematical challenges, they have been studied extensively over the last decades. Nevertheless, the solution of three dimensional transient inverse heat conduction problems are still computationally expensive. Commonly used solution approaches include the regularization-based approaches such as Tikhonov regularization or iterative regularization that result in formulating and solving optimization problems. A radically different solution approach is presented in this paper to provide efficient solutions of three dimensional transient inverse heat conduction problems on thin-plates that are used very often in industrial applications. Instead of solving optimization problems subject to constraints given in terms of three dimensional partial differential equations, the suggested approach transforms the inverse problem into an easy-to-solve direct problem that only needs the reconstruction of a Dirichlet boundary condition. This yields an approximated solution. Furthermore, a new time-space adaptive mesh refinement strategy is proposed to further reduce computational effort at an acceptable level of estimation precision. The accuracy and efficiency of the proposed sequential approach as well as the time-space adaptive mesh refinement strategy are validated by four representative case studies arising from practice. Estimation results with experimental data are also presented. The current work is considered as an important step forward towards the efficient solution of transient three dimensional inverse heat conduction problems, which is particularly useful for developing heat-flux soft sensors in practical problems arising from different fields such as pool boiling, falling films and steelmaking.

A NiO flake and reduced graphene oxide sheet (NiO/RGO) composite was synthesized via an in situ ultrasonic agitation method after heat calcination in a nitrogen atmosphere. The NiO/RGO composite displayed a high reversible capacity of 825 mA h/g after 50 cycles at 100 mA/g, which was higher than the pure NiO flakes (197 mA h/g). The RGO sheets (115 mA h/g) used in lithium-ion batteries as anode materials. The NiO/RGO electrode showed excellent rate capacities that were higher than the pure NiO flakes and the RGO sheets electrodes within the same experimental conditions. These improvements could be attributed to the RGO sheets improved the electrical conductivity of NiO flakes and buffered the volume expansion of the NiO/RGO composite electrode during lithium cycling.

In this paper, a type of macroporous carbon (MPC) material was produced using water-soluble sodium carbonate (Na2CO3) as the template and glucose as the carbon precursor. After annealing in an argon atmosphere (Ar) at 700 °C, the samples exhibited specific surface areas up to 600 m2 g−1 with different proportions of sodium carbonate and glucose. When the samples were employed as anode materials in lithium-ion batteries, the electrodes delivered a stable reversible capacity at 200 mA g−1 and favourable cycling stability at 500 mA g−1. Moreover, all MPC samples exhibited excellent rate performances at 5000 mA g−1.

The UC1-xNx solid solution modified layers that improve corrosion resistance and surface hardness of uranium were prepared by pulsed laser irradiating the surface uranium in the mixed atmospheres where the partial pressure ratios of CH4 to N2 are 1:2, 1:1 and 2:1, respectively. The SEM images show that the distribution of micro-cracks in the modified layers decreases significantly with the increase of partial pressure of CH4 in the mixed atmospheres. The phase structure and chemical composition of the modified layers were investigated by XRD and AES. XRD results show that the composition of the carbonitride modified layers is mainly UC1-xNx solid solution, only with a small amount of free uranium and uranium dioxide. AES results reveal that the C and N contents in the UC1-xNx solid solution can be adjusted by the respective partial pressure of CH4 and N2. The U 4f, N 1s and C 1s core-level also confirmed that the UC1-xNx solid solution is the main component in the laser modified layers. Electrochemical polarization tests were conducted in 0.02 mol/L NaCl solution and the results indicated that the carbonitride modified layer prepared in an atmosphere where the ratio of CH4 to N2 at 1:2 have excellent corrosion resistance, its self-corrosive potential and self-corrosive current are −2.28 × 10−1 V and 5.56 × 10−8 A/cm2, respectively, while the values of the uranium are −5.67 × 10−1 V and 8.08 × 10−7 A/cm2, respectively. Nano-indentation measurement results show that the average hardness at different depths of these modified layers is between 7 GPa and 9 GPa, while the average value of the uranium is 4.1 GPa.

The experts of Taiwan Association for the Study of Liver (TASL) have actively participated and led the guidelines on hepatitis B virus (HBV) management by Asian Pacific Association for the Study of Liver (APASL) which is the first international association for the study of liver to publish the statement on HBV management before. However, there are more and more new data on the natural history and treatment of HBV infection in the past decade. These include new application of an old biomarker (quantitative HBsAg), clinical significance of HBV genotype and naturally occurring mutations, the role of non-invasive examination in evaluating severity of hepatic fibrosis, clinical significance of outcome calculators, new drug or new combination strategies towards more effective therapy and organ transplantation including liver and non-liver transplantation. It is time to publish the guidelines on HBV management of Taiwan. Hence, TASL have conducted an expert meeting to review, to discuss and to debate the relevant literatures, followed by draft the manuscript of HBV management guidelines and recommendations. The guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patient receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included. Keywords: Chronic hepatitis B, Pegylated interferon alfa, Entecavir, Tenofovir disoproxil fumarate, Tenofovir alafenamide

Recently, a new monolayer Group III–V material, two-dimensional boron phosphide (BP), has shown great potential for energy storage and energy conversion applications. We study the thermoelectric properties of BP monolayer as well as the effect of functionalization by first-principles calculation and Boltzmann transport theory. Combined with a moderate bandgap of 0.90 eV and ultra-high carrier mobility, a large ZT value of 0.255 at 300 K is predicted for two-dimensional BP. While the drastically reduced thermal conductivity in hydrogenated and fluorinated BP is favored for thermoelectric conversion, the decreased carrier mobility has limited the improvement of thermoelectric figure of merit.

The research on graphene-based anode materials for high-performance lithium-ion batteries (LIBs) has been prevalent in recent years. In the present work, carbon-coated SnO

Nanozymes have been widely applied in bio-assays in the field of biotechnology and biomedicines. However, the physicochemical basis of nanozyme catalytic activity remains elusive. To test whether nanozymes exhibit an inactivation effect similar to that of natural enzymes, we used guanidine chloride (GuHCl) to disturb the iron oxide nanozyme (IONzyme) and observed that GuHCl induced IONzyme aggregation and that the peroxidase-like activity of IONzyme significantly decreased in the presence of GuHCl. However, the aggregation appeared to be unrelated to the quick process of inactivation, as GuHCl acted as a reversible inhibitor of IONzyme instead of a solo denaturant. Inhibition kinetic analysis showed that GuHCl binds to IONzyme competitively with H2O2 but non-competitively with tetramethylbenzidine. In addition, electron spin resonance spectroscopy showed that increasing GuHCl level of GuHCl induced a correlated pattern of changes in the activity and the state of the unpaired electrons of the IONzymes. This result indicates that GuHCl probably directly interacts with the iron atoms of IONzyme and affects the electron density of iron, which may then induce IONzyme inactivation. These findings not only contribute to understanding the essence of nanozyme catalytic activity but also suggest a practically feasible method to regulate the catalytic activity of IONzyme.

NiO-ZnO/RGO composite was obtained by the annealing of an Ni (OH) 2 -Zn (OH) 2 /RGO precursor, which has been fabricated by in situ ultrasonic agitation. Moreover, the NiO-ZnO nanoflakes are evenly distributed on the RGO sheets based on the scanning electron microscope (SEM) and transmission electron microscope (TEM) characterization results. When the NiO-ZnO/RGO composite was used as an anode material in lithium-ion batteries (LIBs), the electrodes exhibited a high reversible capacity of 1017 mA h/g at a current density of 100 mA/g after 200 cycles and a specific capacity of 458 mA h/g at 500 mA/g even after 400 cycles. The electrode even reached a capacity of 185 mA h/g at a current density of 2000 mA/g. The excellent electrochemical properties of the NiO-ZnO/RGO composite might be attributable to the NiO-ZnO nanoflakes offering rich electrochemical reaction sites and shortening the diffusion length for lithium ion (Li + ), as well as the RGO sheets improving the transfer rates of Li + and electron during the charge-discharge process.

Fusiform shape MnO/C composite was fabricated for the first time by heat calcining of MnCO3/C precursor, which was produced via a two-step hydrothermal method using glycine, KMnO4 and glucose as reagents. When the composite applied in LIBs as anode materials, the electrodes deliver a reversible capacity as high as 691 mA h g−1 after 120 cycles at a current density of 100 mA g−1 and can retain a stable capacity of 187 mA h g−1 at 1000 mA g−1. Compared with pure MnO particles sample, the enhanced electrochemical performances of MnO/C electrodes were attributed to the carbon layers can effectively improve the transfer rate of electrons and buffer the volume expansion of MnO particles during the charge/discharge process.

Boiling heat transfer is widely used in industry and in daily life and it can be enhanced by micro/nano surface modification. Herein, we study the pool boiling characteristics of the micro nano bi-porous copper surface with optimal cavity size from other researchers and present an efficient way to further enhance its boiling heat transfer performance by wettability modification of enlarging the particle size to lower the surface energy. In this work, two micro nano bi-porous copper surface samples were prepared and compared with conventional surfaces. One is the original micro nano bi-porous copper surface (Sample#O) prepared using the hydrogen bubble template deposition method to form abundant pores in optimal cavity size, and the other one is the modified micro nano bi-porous copper surface (Sample#M) that is modified by applying a low current density on Sample#O for a few minutes. Scanning Electron Microscope (SEM) images show that Sample#M keeps the pore size but enlarges the nano dendrite on the top of pore wall to micro balls. The conducted pool boiling experiments indicate that both micro nano bi-porous copper surfaces have superior heat transfer coefficients than the plain copper surface, and the high-speed camera shows that the micro nano bi-porous copper surfaces have shorter bubble growth periods than those surfaces with pure nano structure or pure micro structure. At a heat flux of 90 W cm−2, the heat transfer coefficient of Sample#O is 13 W cm−2 K−1, which is 2.8 times over that of the plain surface. Compared to Sample#O, Sample#M can further enhance the pool boiling heat transfer. At the same heat flux of about 90 W cm−2, the heat transfer coefficient of Sample#M is 23 W cm−2 K−1, which is 1.7 times over that of Sample#O and 4.8 times over that of the plain surface. The heat transfer coefficient of Sample#M can be as high as 30 W cm−2 K−1 when it reaches the CHF. High-speed camera images show that highest bubble growth period for Sample#M is just less than 20 ms, which is shorter than that of Sample#O having a value in between 20 ms and 40 ms. It confirms that Sample#M after wettability modification has a lower interface energy which can accelerate the bubbles departure, and has an even more superior heat transfer performance than Sample#O.

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

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.