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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 phase equilibria and thermodynamic properties of the U–Nb system were investigated through experiments and thermodynamic modeling. In the experiments, a series of samples with different content of Nb were prepared by arc melting. The Nb content covers the entire composition range of the U–Nb binary system. After solidification, the samples were annealed and then analyzed by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, differential scanning calorimeter and neutron diffraction. The equilibrium phases, including γ1 (U-rich bcc), αU, and γ2 (U-depleted bcc), were determined in detail from the experimental characterization. The occurrence of the invariant reaction γ1→ αU + γ2 was confirmed, and the reaction temperature and composition were accurately identified. Moreover, the experimental findings clarify the dispute between the Dwight and Terekhov theories regarding the phase region (i.e., whether the phase region is αU + γ1 or βU + γ2). Furthermore, the U–Nb phase diagram was reassessed by incorporating the present experimental data and previously published reliable experimental data from the literature. A set of self-consistent thermodynamic parameters were developed using CALPHAD (Calculation of phase diagrams), and the calculations reasonably agree with the experimental observations.

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 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-1 at 100 mA g-1 after 80 cycles, reaching an initial coulombic efficiency (CE) of up to 60.6%. Furthermore, the as-prepared MnCO₃/MWCNT composite displays more excellent rate performances than the pure multiwalled carbon nanotube (MWCNT) and pure MnCO₃ particles. The reason is that the MnCO₃ particles can be effectively connected by the MWCNT, thus enhancing the electrochemical performance of the MnCO₃/MWCNT composite.

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.

An N-doped MnO/rGO composite (N-MnO/rGO) was successfully fabricated by a one-step hydrothermal method in which histidine and potassium permanganate (KMnO4) reacted in water containing graphene oxide, and the product was then calcinated in a nitrogen (N2) atmosphere. The N-MnO/rGO presents an excellent lithium-storage capability. It shows a high reversible specific capacity of 1020 mA h g−1 at a current density of 200 mA g−1 after 150 cycles and 760 mA h g−1 at a current density of 500 mA g−1 after 200 cycles. Meanwhile, the N-MnO/rGO sample presents a stable rate capability from 100 to 2000 mA g−1. Even at 2000 mA g−1, the electrode delivers 335 mA h g−1, which is higher than the capability for the pure MnO particles and rGO sheets. The outstanding electrochemical performances of the N-MnO/rGO electrodes may be attributed to the combined effect of the rGO with N-doping that can effectively buffer the large volume expansion of the MnO particles and can enhance the transport rates of lithium ions and electrons during lithium cycling.

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