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Magnesium alloy, as an absorbable and implantable biomaterial, has been greatly developed in the application field of biomaterials in recent years due to its excellent biocompatibility and biomechanics. However, due to the poor corrosion resistance of magnesium alloy in the physiological environment, the degradation rate will be unbalanced, which seriously affects the clinical use. There are two main ways to improve the corrosion resistance of magnesium alloy: one is by adding alloying elements, the other is by surface modification technology. Compared with adding alloy elements, the surface coating modification has the following advantages: (1) The surface coating modification is carried out without changing the matrix elements of magnesium alloy, avoiding the introduction of other elements; (2) The corrosion resistance of magnesium alloy can be improved by relatively simple physical, chemical, or electrochemical improvement. From the perspective of corrosion resistance and biocompatibility of biomedical magnesium alloy materials, this paper summarizes the application and characteristics of six different surface coating modifications in the biomedical magnesium alloy field, including chemical conversion method, micro-arc oxidation method, sol-gel method, electrophoretic deposition, hydrothermal method, and thermal spraying method. In the last section, it looks forward to the development prospect of surface coating modification and points out that preparing modified coatings on the implant surface combined with various modification post-treatment technologies is the main direction to improve biocompatibility and realize clinical functionalization.

Background: The myocardium is susceptible to lipopolysaccharide (LPS)-induced damage in sepsis, and cardiac dysfunction is a leading cause of mortality in patients with sepsis. The changes in cardiomyocyte autophagy in sepsis and the effects and mechanism of action of capsaicin (Cap) remain unclear.Methods and Results: The potential pathway of 14-3-3γ-dependent autophagy and the effects and mechanisms of Cap were studied in LPS-induced injury to primary cultured neonatal rat cardiomyocytes. The results showed that cardiomyocyte viability decreased, lactate dehydrogenase and creatine kinase activities increased, 14-3-3γ expression was downregulated, and autophagy was inhibited after LPS challenge. Cap pretreatment augmented autophagy by upregulating 14-3-3γ expression and activating AMP-activated protein kinase (AMPK) and unc-51 like autophagy-activating kinase 1 (ULK1), suppressing mammalian target of rapamycin (mTOR), alleviating cardiac dysfunction and improving the inflammation response, whereas pAD/14-3-3γ-shRNA nullified the above effects. Cap pretreatment also decreased the levels of IL-1β, TNF-α, IL-6, and IL-10; suppressed intracellular oxidative stress; reduced the intracellular/mitochondrial reactive oxygen species (ROS); balanced GSH/GSSG; increased GSH-Px, catalase, and SOD activities; and decreased MDA contents. It also increased ATP content, activated complex Ⅰ and complex Ⅲ, stabilized the mitochondrial membrane potential, and decreased the mitochondrial permeability transition pore opening, thereby improving mitochondrial function.Conclusion: Pretreatment with Cap can regulate autophagy by upregulating 14-3-3γ expression, inhibiting oxidative stress and inflammation, maintaining mitochondrial function, and protecting cardiomyocytes against LPS-induced injury.

The complete mitochondrial genome of Dryopteris crassirhizoma was sequenced for the first time. The mitochondrial genome length was 313,346 bp, with 48.58% GC contents. There were 94 genes annotated, including 27 known protein-coding genes, 49 tRNAs, and 18 rRNAs. The maximum likelihood method was used to establish the phylogenetic tree of six species. The phylogenetic results showed that D. crassirhizoma was sister to Ophioglossum californicum. It reveals the genetic relationship between different species and provides a theoretical basis for the establishment of a classification system.

In situ synthesis feasibility of ZrB2-SiC-ZrC composite coatings on ZrC ceramics by reactive plasma spraying (RPS) was investigated. To help to understand the phase evolution during plasma spraying process, reaction behavior in the ZrH2-Si-B4C system was explored carefully by differential scanning calorimetry. The results indicated that the phase transformation sequence in the ZrH2-Si-B4C system could be described as ZrH1.66, Zr3O, ZrC, ZrB2, Zr2Si, ZrSi, and SiC. The prior formation of ZrC was due to high diffusion rate of C atoms from B4C. ZrB2 was produced above 1100 °C. As the temperature increased, SiC were finally formed by the reaction of ZrC with ZrSi and B4C. The RPS composite coatings mainly consisted of ZrB2, SiC, and ZrC phases, except for a small fraction of ZrO2 phase. The microstructural characterization exhibited more dense melted splats, which appears to increase gradually with the increase in spraying currents and distances. The coatings had typical lamellar structure and adhered to the substrate well. The microhardness values were higher than 1000 HV1, but there were few variations with varying spraying currents and distances.

In the marine service environment, metal materials have a serious risk of corrosion. The corrosion rate of metal materials will be accelerated by the dual action of temperature change and alkali salt in saline-alkali environment. In order to delay the metal materials’ corrosion rate and prolong their service life, this paper used a CeO2–GO (4:1) nanocomposite prepared by the hydrothermal synthesis method to make an anticorrosion coating. The anticorrosion performance was evaluated by stereo microscope and 3D images of the corrosion site were fitted for calculation. The state evolution of the CeO2–GO (4:1)/EP coating immerged in a simulated saline-alkali solution was studied by open circuit potential (OCP), electrochemical alternating current impedance spectroscopy (EIS), Mott–Schottky curve and Tafel curve. The results indicated that CeO2–GO (4:1) nanocomposites exhibited good resistance compared with graphene oxide and nano cerium oxide in a simulated saline-alkali environment. The research in this paper lays a firm theoretical foundation for the application of nano cerium-oxide-modified graphene oxide anticorrosive coating in saline-alkali environment engineering.

Kaempferol (Kae), a flavonoid, has been found in fruits and other vegetables, possesses many biological activities. 14-3-3 protein exerts protection on various types of injured tissues and cells. Doxorubicin (Dox) causes excessive reactive oxygen species (ROS) generation, which induces endotheliotoxicity and cardiotoxicity. We hypothesized that Kae could protect vascular endothelium by regulating 14-3-3γ or related pathways against Dox toxicity. HUVECs were established Dox-toxic injury models. Kae’s effects were assessed with many physiological, enzymatic, cellular, and molecular biological indexes. Our results showed that Dox-induced damage in HUVECs were reduced through Kae to promote the expression of total protein 14-3-3γ and mitochondrial Bcl-2, phosphorylate Bad, increase cell viability, NO content, DDAHⅡactivity, p-eNOS/eNOS ratio, and MMP levels, maintained NAD+/NADH and GSH/GSSG balance, and decrease LDH and caspase-3 activities, ADMA content, ROS generation, mPTP openness, and apoptosis. Kae’s effects were abolished with pAD/14-3-3γ-shRNA downregulating 14-3-3γ expression, or ABT-737 inhibiting Bcl-2 activity. This study demonstrated that Kae protected the vascular endothelium against Dox-induced damage by regulating 14-3-3γ and ADMA/DDAHⅡ/eNOS/NO pathway, inhibiting oxidative stress, and improving mitochondrial function.

Background: Doxorubicin (Dox) can induce endotheliotoxicity and damage the vascular endothelium (VE). The most principle mechanism might be excess reactive oxygen species (ROS) generation. Nevertheless, the characteristics of ROS generation, downstream mechanisms, and target organelles in Dox-induced endotheliotoxicity have yet to be elucidated.Methods and Results: In order to explore the related problems, the VE injury models were established in mice and human umbilical vein endothelial cells (HUVECs) by Dox-induced endotheliotoxicity. Results showed that the activities of lactate dehydrogenase (LDH) and creatine kinase of mice’s serum increased after injected Dox. The thoracic aortic strips’ endothelium-dependent dilation was significantly impaired, seen noticeable inflammatory changes, and brown TUNEL-positive staining in microscopy. After Dox-treated, HUVECs viability lowered, LDH and caspase-3 activities, and apoptotic cells increased. Both intracellular/mitochondrial ROS generation significantly increased, and intracellular ROS generation lagged behind mitochondria. HUVECs treated with Dox plus ciclosporin A (CsA) could basically terminate ROS burst, but plus edaravone (Eda) could only delay or inhibit, but could not completely cancel ROS burst. Meanwhile, the expression of endothelial nitric oxide synthase (eNOS) decreased, especially phosphorylation of eNOS significantly. Then nitric oxide content decreased, the mitochondrial function was impaired, mitochondrial membrane potential (MMP) impeded, mitochondrial swelled, mitochondrial permeability transition pore (mPTP) was opened, and cytochrome C was released from mitochondria into the cytosol.Conclusion: Dox produces excess ROS in the mitochondria, thereby weakens the MMP, opens mPTP, activates the ROS-induced ROS release mechanism, induces ROS burst, and leads to mitochondrial dysfunction, which in turn damages VE. Therefore, interrupting any step of the cycles, as mentioned above can end the related vicious cycle and prevent the occurrence and development of injury.

The orientation of plant roots responds to gravity and influences nutrient acquisition. Here the authors show that the formin RMD buffers movement of specialized gravity-sensing organelles and report enhanced RMD expression during phosphate deficiency that could alter root angle to improve phosphate uptake.

Irreversible electroporation (IRE) is an emerging minimally invasive tumor ablation technique that delivers short pulses of strong electric fields and kills cancer cells by disrupting their cell membranes with the electric pulses. However, clinical studies report that more than 10% of local tumor recurrences occur at the original ablated site. NVP BEZ-235 (BEZ) is a dual PI3K/mTOR inhibitor that has substantial anticancer effects. However, the clinical trials of BEZ was not satisfactory because of its low bioavailability and high toxicity, which stemmed from the use of oral administration of high doses over a long period of time. In this research, we prepared a liposomal formulation of BEZ (L-BEZ) for intratumoral injection and studied its antitumor efficacy alone and in combination with IRE. We hypothesized that IRE could release BEZ from the liposomes and that the combination could decrease tumor viability. Our results show that IRE released BEZ from its liposomal encapsulation. The combination of L-BEZ and IRE killed more Hep3B tumor cells in vitro than did L-BEZ or IRE alone and also inhibited cancer cell proliferation in nude mice bearing Hep3B xenografts. Combination of chemotherapeutic agent loaded nanoparticles could enhance the antitumor efficacy of IRE.

When determining elements in geochemical samples, the sample is usually decomposed by mixed acid (hydrochloric acid-hydrofluoric acid-perchloric acid) by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). However, the different proportions of mixed acid have a great influence on sample decomposition, resulting in lower analytical results of chromium, manganese, iron, aluminum, titanium and parts of rare earth elements, and bad analytical precision. In this study, samples are digested by mixed solution of inverse aqua regia, hydrofluoric acid, and perchloric acid, and then extracted by inverse aqua regia. This improves the decomposition of the above elements, especially for samples with high contents of these elements. Results show that the relative standard deviation (n=6) ranges from 0.34% to 4.02% for repeated determination of national level standard materials when 0.1 g sample was digested by 8 mL inverse aqua regia, 6 mL hydrofluoric acid, and 3 mL perchloric acid, and then extracted by 8 mL inverse aqua regia. The accuracy and precision of this method can satisfy the quality control standard requirements of the geology laboratory. This method establishes a fast and accurate approach to batch determination of multielements in geochemical samples.

Abstract Failure to remove a retrievable inferior vena cava (IVC) filter can cause severe complications with high treatment costs. Polydioxanone (PPDO) has been shown to be a good candidate material for resorbable IVC filters. However, PPDO is radioluscent under conventional imaging modalities. Thus, the positioning and integrity of these PPDO filters cannot be monitored by computed tomography (CT) or x-ray. Here we report the development of radiopaque PPDO IVC filters based on gold nanoparticles (AuNPs). Commercially available PPDO sutures were infused with AuNPs. Scanning electron microscopy analysis confirmed the presence of AuNP on the surface of PPDO. Micro-CT and x-ray images of the AuNP-infused PPDO sutures showed significant signal enhancement compared to untreated PPDO sutures. Elemental analysis showed that gold loading exceeded 2000 ppm. Tensile strength and in vitro cytotoxicity showed no significant difference between AuNP-infused and untreated PPDO. In a 10-week stability study, neither the gold content nor the radiopacity of the infused PPDO sutures significantly changed in the first 6 weeks. The increased attenuation of AuNP-infused PPDO sutures indicates their major advantage as a radiopaque resorbable filter material, as the radiopacity allows monitoring of the position and integrity of the filter, thereby increasing its safety and efficacy.

The magnesium alloys Mg-0.5Mn-2Zn, Mg-1.0Mn-2Zn, and Mg-1.5Mn-2Zn (wt.%) with potential biomedical applications, synthesized by powder metallurgy, were investigated to evaluate the influence of manganese content on their microstructure, mechanical properties, and corrosion resistance. The results show that Mg-Mn-Zn alloys prepared by powder metallurgy reached the maximum compressive stress of 316 MPa and the maximum bending strength of 186 MPa, showing their good resistance to compression and bending, and meeting the mechanical properties required for the human bone plate. With an increase in manganese content, the corrosion resistance improved. In the polarization curve, the maximum positive shift of corrosion potential was 92 mV and the maximum decrease of corrosion current density was 10.2%. It was concluded that, of the alloys tested, Mg-1.0Mn-2.0Zn (wt.%) had the best overall performance, and its maximum compressive stress force and corrosion current density reached 232.42 MPa and 1.32 × 10−5 A·cm−2, respectively, being more suitable for service in human body fluids.

Al and aluminum alloys are widely used in the transportation industry and aerospace field owing to their low density. They are always utilized as the sheathing materials, whose corrosion resistances need special attention. In the study, the electrochemical impedance spectroscopy (EIS) measurements and potentiodynamic polarization tests are performed on pure Al, aluminum alloys 2A97, 6061, 7050 and 2024. The corrosion behaviors of the five materials are respectively characterized by the resultant indicators, such as the corrosion potential E _c , the corrosion current density I _c , the corroded surface morphology and the frequency characteristics. The materials sequences that determined respectively by these indicators are compared with each other. The conflicts among these sequences are found. Then potentiostatic polarization measurements are carried out on the five materials. The instantaneous characteristic of the corrosion potential and polarization current density of each material during its corrosion process is revealed. Because of the characteristic, it is concluded that the potentiostatic polarization measurement and resultant polarization current density are more suitable to characterize the corrosion behaviors of Al and aluminum alloys. The investigation could provide help in the exploitation of new aluminum alloys with the better corrosion property.

A large number of domestic and international literatures have studied the pavement performance of composite modification of Buton rock asphalt and different asphalt modifiers. It is found that basalt blending can greatly improve the performance in an all-round way, in which high-temperature stability and low-temperature cracking resistance have superimposed effect. Waste rubber powder blending has little overall performance improvement. With diatomite blending the performance can exceed SBS modified asphalt. The research on composite modification of Buton rock asphalt still needs further study.

This article traces the essence of the tourist souvenir design, explaining the core of its value, the essence of local culture, and emphasizing the law of souvenir market value that maintains the uniqueness of local culture to attract purchases. By analysing the current situation of design homogeneity and lack of innovation in Chinese market, it proposes an innovative idea, “Back to Design Origins”. Then taking Nanjing souvenir design as an example, it introduces two innovative approaches, “Discovery and Application of New Cultural Elements” and “ Cute Stylization of Traditional Symbols”. In the end, it summarizes several feasible rules on element selection, symbolic method application, and carrier selection, mainly based on the thought of “Back to Design Origins”.

Recently, non-linear statistical measures such as multi-scale entropy (MSE) have been introduced as indices of the complexity of electrophysiology and fMRI time-series across multiple time scales. In this work, we investigated the neurophysiological underpinnings of complexity (MSE) of electrophysiology and fMRI signals and their relations to functional connectivity (FC). MSE and FC analyses were performed on simulated data using neural mass model based brain network model with the Brain Dynamics Toolbox, on animal models with concurrent recording of fMRI and electrophysiology in conjunction with pharmacological manipulations, and on resting-state fMRI data from the Human Connectome Project. Our results show that the complexity of regional electrophysiology and fMRI signals is positively correlated with network FC. The associations between MSE and FC are dependent on the temporal scales or frequencies, with higher associations between MSE and FC at lower temporal frequencies. Our results from theoretical modeling, animal experiment and human fMRI indicate that (1) Regional neural complexity and network FC may be two related aspects of brain's information processing: the more complex regional neural activity, the higher FC this region has with other brain regions; (2) MSE at high and low frequencies may represent local and distributed information processing across brain regions. Based on literature and our data, we propose that the complexity of regional neural signals may serve as an index of the brain's capacity of information processing—increased complexity may indicate greater transition or exploration between different states of brain networks, thereby a greater propensity for information processing.

A surface film generates on AZ21 magnesium alloy in magnesium sulfate solutions,resulting in serious voltage delay.Pulse current is conducive to the application of AZ21 magnesium alloy in a battery,for it can shorten the lag time,reduce the initial discharge voltage drop and increase the discharge stability. The voltage delay of AZ21 magnesium alloy in a 2 mol·L-1 MgSO4 solution was investigated by chronopotentiometry,multi-current steps,electrochemical impedance measurement,and scanning electron microscopy. After a 50 mA pulse current was applied for 1 s,the voltage lag time of AZ21 magnesium alloy decreased from 6.35 s(3.23 V) to 0.59 s(0.034 V).

Irreversible electroporation (IRE) kills tumor cells by the delivery of short pulses of strong electric fields. However, the field strength decreases with distance from the treatment center. When IRE cannot eradicate the entire tumor mass, the surviving tumor cells can regrow. NVP-BEZ235 is a dual PI3K/mTOR inhibitor that has been administered orally in clinical trials. However, its hydrophobicity and poor water solubility make NVP-BEZ235 difficult to deliver to target areas. To improve its pharmacokinetics and therapeutic efficacy, we have encapsulated NVP-BEZ235 in a liposome (termed as L-BEZ). Our current study focuses on the long-term antitumor efficacy of IRE and intratumoral injection of L-BEZ in HN5 head and neck cancer xenografts in nude mice. We compared in vitro efficacy, as well as the effect on tumor size and growth rate in vivo, between IRE alone, IRE + oral BEZ, and IRE + L-BEZ over the course of two months. All animals in the control group were sacrificed by day 36, due to excess tumor burden. Tumors treated with IRE alone grew faster and larger than those in the control group. IRE + oral BEZ suppressed tumor growth, but the growth rate increased to that of the controls toward the end of 21 days. Only IRE + L-BEZ eradicated the tumor masses, with no palpable or extractable tumor mass observed after two months. The combination of IRE and L-BEZ could effectively eradicate tumors and prevent recurrence.

In order to study the influences of the contents of short fiber on the mechanical properties of concrete matrix, the properties of compressive, flexure and splitting of concrete matrix reinforced by alkali resistant glass fiber and calcium carbonate whisker were tested. To study the reinforced effect of different scale fibers on the flexure behavior of fine concrete sheets, the flexural tests of concrete sheet of fine concrete reinforced with basalt fiber mesh and short fiber composites were carried out. The results show that the properties of the compressive, flexure and splitting of fine concrete reinforced with appropriate amount of alkali resistant glass fiber and carbonate whisker are improved compared with that of concrete reinforced by one type of fiber. The flexure properties of the concrete sheets are improved obviously when continuous fiber textile and short fiber composite are adopted to reinforce.

As a widely used reinforcement method in tunnel engineering, the accuracy of models in numerical analysis has a vital influence on the reliability of the analysis results. To solve the problem of hard modeling for complicated models, this paper proposes to build models of different characteristics automatically by the means of Enterprise Knowledge Language (EKL) of CATIA, combining knowledge engineering template with parameterization. Furthermore, the stability of surrounding rocks and the distribution features of plastic areas were studied in different cases by CATIA-ABAQUS model. Besides, the effects and contributions of several parameters, including the rock-bolt diameter and interval between rock-bolts have been studied. It was found that: (1) Rock-bolt has a notable effect on the stability of the surrounding rocks. Increasing the diameter of rock-bolts contributes to significantly reduce the plastic area and the vertical displacement. With the increase of the quantity and the diameter of anchors, the degree of influence gradually weakens, showing the logarithmic relationship; (2) When the quantity and diameter of rock-bolts are constant, in the case in which the intervals between rock-bolts are various, the plastic area of surrounding rocks and the axial stress of rock-bolts are larger than that of the same distance, while the vertical displacement are uniform. (3) The excavation process has a great influence on the axial stress of rock-bolts and the redistribution of stresses in the surrounding rock.

Constructed wetland (CW) is a low cost and easy operation process for wastewater treatment, while filler clogging is one of the disadvantages for this technology. Using activated carbon as the filler, a regular CW and an integration of constructed wetland with microbial fuel cell (CW-MFC) were constructed. After continuous operation of four months, specific surface area and pore size distribution of the activated carbon were analyzed. The specific surface area of the fresh activated carbon was 133.8 m2/g, while the filler in the CW and CW-MFC systems had specific surface area of 38.1 m2/g and 58.2 m2/g. The surface decrease of the CW-MFC filler was 21% lower than that of CW filler. Comparing with the regular CW, the filler in the CW-MFC was more clogging resistant. The alleviation of the filler clogging in CW-MFC may be caused by the micro-electric field as the function of MFC. CW-MFC is a promising microbial electrochemical technology for wastewater treatment and filler clogging resistant, there are some detailed issues deserve to be further researched.