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Acinetobacter baumannii is a pathogenic bacterium widespread in human environments, especially in intensive care units, and is associated with high morbidity and infection rates. Multiple drug resistance in A. baumannii frequently leads to the death of patients, making the development of multi-effect antibacterial agents against this bacterium a research hotspot. We have previously found that the X33 antimicrobial oligopeptide can effectively inhibit the growth of Penicillium digitatum and Candida albicans. Herein, we evaluated the antibacterial activity of X33 antimicrobial oligopeptide against A. baumannii by determining the minimum inhibitory concentration, inhibition zone, and growth curve. The increase in extracellular alkaline phosphatase and the leakage of intracellular compounds confirmed the effect of X33 antimicrobial oligopeptide on the cell wall and membrane. Changes in reactive oxygen species, malondialdehyde, ATP, reducing sugar, soluble protein, and pyruvate content demonstrated that the incubation with X33 antimicrobial oligopeptide affected energy metabolism and oxidative stress. Consistent with the physiological characteristics, transcriptomics analysis indicated that incubation with X33 antimicrobial oligopeptide significantly induced changes in the expression of 2339 genes, including 1262 upregulated and 1077 downregulated genes, which participate in oxidative phosphorylation, ribosome, quorum sensing, fatty acid degradation, glycolysis/gluconeogenesis, and citrate cycle pathways. These results provide a fundamental basis for investigating the mechanism of X33 antimicrobial oligopeptide as a potential drug against A. baumannii. [ABSTRACT FROM AUTHOR]

Forest resources are the most important natural resources; their dynamic changes (growth or decline) are affected by socio-economic factors, and to study their linkage is of great significance. However, the relationship between forest resources and social economic factors is normally a multivariate nonlinear relationship. There are difficulties in accurately analyzing it by using traditional multivariate-statistical methods. Also, its explicit mathematical model is inconvenient for intelligent management. In this paper, the radial basis function (RBF) neural network was introduced to study the relationship between the changes of forest resources and socio-economic factors and was evaluated by comparison with the traditional multiple-linear regression model. The results showed that the RBF neural network method can be applied in modeling the dynamic changes of forest resources and showed a higher prediction accuracy over the traditional statistical modeling approaches. At the same time, the RBF neural network can analyze and evaluate the importance of influencing factors simply and conveniently. The results provide a new way and show an application potential for the analysis and intelligent management in forest resources. [ABSTRACT FROM AUTHOR]

Compression of alfalfa into briquettes is an effective way to solve the problem of storage and transportation. In the process of compression, heat is generated and the temperature is raised in the material. In fact, the appropriate temperature can improve the quality of alfalfa briquettes and reduce the energy consumption of densification. In this study, the effect of assisted vibration on the compression temperature was tested. The results showed that when the vibration frequency was below 15 Hz, the temperature at the center and side in compressed alfalfa increased slowly with compression time. When the vibration frequency was above 20 Hz, it increased first and then decreased with the increase of time. Moreover, the maximum temperature value increased remarkably when the frequency was above 20 Hz. In the same vibration frequency and compression time, the center temperature in the compressed alfalfa was higher than the side temperature. The experimental results provide a reference for the determination of reasonable vibration parameters, and explanation of the effect of vibration on reducing energy consumption. [ABSTRACT FROM AUTHOR]

College students are the core movie consumption group. Based on the theory of planned behavior, movie-viewing preferences and behaviors of 430 college students in Shanxi Province were studied against the background of the rapid rise of original content movies made by streaming media platforms--streaming self-produced movies. Multiple regression analysis was carried out on the factors influencing college students' movie-viewing behavior. A model was constructed applicable to the movie-viewing behavior relevant to streaming self-produced movies in college students in Shanxi Province. The main results showed that three movie-viewing behaviors of college students (paid viewing, first selection, and recommendation to others) were affected by eight factors to different degrees, namely, film traits, social environment, internet word-of-mouth, perceived cost, perceived usefulness, perceived quality, attitudes to enterprise image, attitudes to movie product. This paper is expected to provide an important reference for development trends and investment decisions adopted for streaming self-produced movies. [ABSTRACT FROM AUTHOR]

Previous studies have suggested that immune system development and weaning stress are closely related to the maturation of gut microbiota. The early-life period is a “window of opportunity” for microbial colonization, which potentially has a critical impact on the development of the immune system. Fecal microbiota transplantation (FMT) and probiotics are often used to regulate gut microbial colonization. This study aims to test whether early intervention with FMT using fecal microbiota from gestation sows combined with Clostridium butyricum and Saccharomyces boulardii (FMT-CS) administration could promote the maturation of gut microbiota and development of immune system in piglets. Piglets were assigned to control (n = 84) and FMT-CS treatment (n = 106), which were treated with placebo and bacterial suspension during the first three days after birth, respectively. By 16S rRNA gene sequencing, we found that FMT-CS increased the α-diversity and reduced the unweighted UniFrac distances of the OTU community. Besides, FMT-CS increased the relative abundance of beneficial bacteria, while decreasing that of opportunistic pathogens. FMT-CS also enhanced the relative abundance of genes related to cofactors and vitamin, energy, and amino acid metabolisms during the early-life period. ELISA analysis revealed that FMT-CS gave rise to the plasma concentrations of IL-23, IL-17, and IL-22, as well as the plasma levels of anti-M.hyo and anti-PCV2 antibodies. Furthermore, the FMT-CS-treated piglets showed decreases in inflammation levels and oxidative stress injury, and improvement of intestinal barrier function after weaning as well. Taken together, our results suggest that early-life intervention with FMT-CS could promote the development of innate and adaptive immune system and vaccine efficacy, and subsequently alleviate weaning stress through promoting the maturation of gut microbiota in piglets. [ABSTRACT FROM AUTHOR]

Schizosaccharomyces pombe Php4 is the regulatory subunit of the CCAAT-binding complexes and plays an important role in the regulation of iron homeostasis and iron-dependent metabolism. Here, we show that Php4 undergoes ubiquitindependent degradation in the late logarithmic and stationary phases. The degradation and ubiquitination of Php4 could be attenuated by deletion of hul6, a gene encoding a putative HECT-type E3 ubiquitin ligase. The expression levels of Hul6 and Php4 are oppositely regulated during cell growth. Hul6 interacts with the C-terminal region of Php4. Two lysine residues (K217 and K274) located in the C-terminal region of Php4 are required for its polyubiquitination. Increasing the levels of Php4 by deletion of hul6 or overexpression of php4 decreased expression of Php4 target proteins involved in iron-dependent metabolic pathways such as the tricarboxylic cycle and mitochondrial oxidative phosphorylation, thus causing increased sensitivity to high-iron and reductions in succinate dehydrogenase and mitochondrial complex II activities. Hul6 is located primarily in the mitochondrial outer membrane and most likely targets cytosolic Php4 for ubiquitination and degradation. Taken together, our data suggest that Hul6 regulates irondependent metabolism through degradation of Php4 under normal growth conditions. Our results also suggest that Hul6 promotes iron-dependent metabolism to help the cell to adapt to a nutrient-starved growth phase. [ABSTRACT FROM AUTHOR]

The routine spermidine (SPD) detection method is time-consuming and laborious due to the lengthy chromatographic separation and/or tedious sample derivatization pretreatment. In this study, direct analysis in real-time ionization mode coupled with mass spectrometry (DART-MS) was developed to rapidly determine the SPD content of 12 bean cultivars. The results were compared in detail with those of the classical UHPLC-ESI-QTOF method. After conducting a series of optimizations, a simple sample extraction procedure employing 80% aqueous methanol, was followed by determination of sample extracts directly without any chromatographic separation or prior derivatization. The validated method showed excellent performance with low limits of detection (LOD of 0.025 mg⋅kg-1) and good recovery rates (102.79-148.44%). The investigation highlighted that the DART-MS method (~1.3 min per three samples) could be used as a high-throughput alternative to the classic UHPLC-ESI-QTOF method (~15 min per three samples). [ABSTRACT FROM AUTHOR]

The electrical generation and detection of elastic waves are the foundation for acoustoelectronic and acoustooptic systems. For surface acoustic wave devices, microelectromechanical/nanoelectromechanical systems, and phononic crystals, tailoring the spatial variation of material properties such as piezoelectric and elastic tensors may bring significant improvements to the system performance. Due to the much slower speed of sound than speed of light in solids, it is desirable to study various electroacoustic behaviors at the mesoscopic length scale. In this work, we demonstrate the interferometric imaging of electromechanical power transduction in ferroelectric lithium niobate domain structures by microwave impedance microscopy. In sharp contrast to the traditional standingwave patterns caused by the superposition of counterpropagating waves, the constructive and destructive fringes in microwave dissipation images exhibit an intriguing one-wavelength periodicity. We show that such unusual interference patterns, which are fundamentally different from the acoustic displacement fields, stem from the nonlocal interaction between electric fields and elastic waves. The results are corroborated by numerical simulations taking into account the sign reversal of piezoelectric tensor in oppositely polarized domains. Our work paves ways to probe nanoscale electroacoustic phenomena in complex structures by near-field electromagnetic imaging. [ABSTRACT FROM AUTHOR]

WEDM and fixed abrasive diamond wire saw are two widely used technologies for cutting silicon ingot in semiconductor industry. When semiconductor is sliced by using WEDM method, although the wire electrode is in contact with workpiece, the processing can still be carried on. This phenomena is different from when the metal is sliced. In this study, a hybrid machining method that combines wire electrical discharge machining(WEDM) and fixed abrasive diamond wire saw into one single process is investigated experimentally. The experimental results show that hybrid machining method can combine the advantages of the two machining methods while avoiding their technical limitations. Compared with wire saw method, hybrid machining method can reduce the scratches of silicon surface and tool wear, and restrain the residual of carbon element. Compared withWEDM, the hybrid machining method can improve the cutting efficiency, reduce the surface roughness and kerf width, and eliminate the recast layer and the surface heat affected zone. It can also affect the surface wettability, which is one of the important surface properties of solid surface. This research will be able to provide a new alternative approach in the field of semiconductor cutting technology. [ABSTRACT FROM AUTHOR]

Nanoscale control of the quasi-two-dimensional electron gas at the LaAlO3/SrTiO3 (LAO/STO) interface by a conductive probe tip has triggered the development of a number of electronic devices. While the spatial distribution of the conductance is crucial for such devices, it is challenging to directly visualize the local electrical properties at the buried interface. Here, we demonstrate conductivity imaging of sketched nanostructures at the LAO/STO interface by microwave impedance microscopy (MIM) with a lateral resolution on the order of 100 nm. The sheet conductance extracted from the MIM data agrees with the transport measurement. The tip-induced insulator-to-metal transition is observed above a threshold voltage of +4 V. Our work paves the way for studying emergent phenomena at oxide interfaces by probing nanoscale conductance distribution. [ABSTRACT FROM AUTHOR]

An alkoxide-catalyzed reduction of benzolactams to isoindoles with silanes was realized. With t-BuOK as the catalyst and Ph2SiH2 as the reductant, a series of benzolactams containing different functional groups were reduced to the corresponding isoindoles, which could be captured by N-phenyl maleimide to form Diels-Alder products in moderate to good yields. Deuterium labeling studies and the hydrosilylation of benzolactam in DMF indicated that the deprotonation of benzolactams took place at C3 potion during the reduction. [ABSTRACT FROM AUTHOR]

The periodic motion near non-principal-axis (NPA) rotation asteroids is proved to be markedly different from that near uniformly rotating bodies due to the complex spin statewith precession, raising challenges in terms of the theoretical implications of dynamical systems. This paper investigates the various periodic motions near the typical NPA asteroid 4179 Toutatis, which will contribute to the understanding of the dynamical environments near the widespread asteroids in the Solar system. A novel method with the incorporation of the ellipsoid–mascon gravitational field model and global optimization is developed to efficiently locate periodic solutions in the system. The numerical results indicate that abundant periodic orbits appear near the NPA asteroids. These various orbits are theoretically classified into five topological types with special attention paid to the cycle stability. Although the concept of classical family disappears in our results, some orbits with the same topological structure constitute various generalized 'families' as the period increases. Among these 'families' a total of 4 kinds of relationships between orbits, including rotation, evolution, distortion and quasi-symmetry, are found to construct the global mapping of these types. To cover the rotation statuses of various NPA asteroids, this paper also discusses the variation of periodic orbits with diverse asteroid spin rates, showing that the scales of some orbits expand, shrink or almost annihilate as the system period changes; meanwhile, their morphology and topology remain unchanged. [ABSTRACT FROM AUTHOR]

Male sex is a risk factor for abdominal aortic aneurysm (AAA). Within the AAA adventitia, infiltrating leukocytes express high levels of inflammasome components. To further elucidate the role of inflammatory cells in the pathogenesis of AAA, we here addressed expression and functionality of inflammasome components in peripheral blood mononuclear cells (PBMC) of AAA patients in association with sex. PBMC and plasma were isolated from 100 vascular patients, including 34 pairs of AAA patients and age/sexmatched non-AAA patients. Male PBMC were found to express significantly higher mRNA levels of AIM2, NLRP3, ASC (PYCARD), CASP1, CASP5, and IL1B (all P < 0.0001) than female PBMC. Within the male patients, PBMC of AAA patients displayed increased mRNA levels of NLRP3 (P = 0.044), CASP1 (P = 0.032) and IL1B (P = 0.0004) compared with matched non-AAA PBMC, whereas there was no difference between female AAA and non-AAA patients. The relative protein level of NLRP3 was significantly lower in PBMC lysates from all AAA patients than in matched controls (P = 0.038), whereas AIM2 and active Caspase-1 (p10) protein levels were significantly increased (P = 0.014 and P = 0.049). ELISA revealed significantly increased IL-1α (mean = 6.34 versus 0.01 pg/mL) and IL-1β plasma levels (mean = 12.07 versus 0.04 pg/mL) in AAA patients. The data indicate that male PBMC display a systemic proinflammatory state with primed inflammasomes that may contribute to AAA-pathogenesis. The AAA-specific inflammasome activation pattern suggests differential regulation of the sensors AIM2 and NLRP3 in inflammatory cells of AAA patients. [ABSTRACT FROM AUTHOR]

Background: Chronic low-grade inflammation is considered a driver of many age-related disorders, including vascular diseases (inflammaging). Inhibition of autophagic capacity with ageing was postulated to generate a pro-inflammatory condition via activation of inflammasomes, a group of Interleukin-1 activating intracellular multi-protein complexes. We thus investigated gene expression of inflammasome components in PBMC of 77 vascular patients (age 22-82) in association with age. Findings: Linear regression of real-time qRT-PCR data revealed a significant positive association of gene expression of each of the inflammasome components with age (Pearson correlation coefficients: AIM2: r = 0.245; P = 0.032; NLRP3: r = 0.367; P = 0.001; ASC (PYCARD): r = 0.252; P = 0.027; CASP1: r = 0.296; P = 0.009; CASP5: r = 0.453; P = 0.00003; IL1B: r = 0.247; P = 0.030). No difference in gene expression of AIM2, NLRP3, ASC CASP1, and CASP5 was detected between PBMC of patients with advanced atherosclerosis and other vascular patients, whereas IL1B expression was increased in PBMC of the latter group (P = 0.0005). Conclusion: The findings reinforce the systemic pro-inflammatory phenotype reported in elderly by demonstrating an increased phase-1 activation of inflammasomes in PBMC of vascular patients. [ABSTRACT FROM AUTHOR]

Background: Chronic low-grade inflammation is considered a driver of many age-related disorders, including vascular diseases (inflammaging). Inhibition of autophagic capacity with ageing was postulated to generate a pro-inflammatory condition via activation of inflammasomes, a group of Interleukin-1 activating intracellular multi-protein complexes. We thus investigated gene expression of inflammasome components in PBMC of 77 vascular patients (age 22-82) in association with age. Findings: Linear regression of real-time qRT-PCR data revealed a significant positive association of gene expression of each of the inflammasome components with age (Pearson correlation coefficients: AIM2: r = 0.245; P = 0.032; NLRP3: r = 0.367; P = 0.001; ASC (PYCARD): r = 0.252; P = 0.027; CASP1: r = 0.296; P = 0.009; CASP5: r = 0.453; P = 0.00003; IL1B: r = 0.247; P = 0.030). No difference in gene expression of AIM2, NLRP3, ASC CASP1, and CASP5 was detected between PBMC of patients with advanced atherosclerosis and other vascular patients, whereas IL1B expression was increased in PBMC of the latter group (P = 0.0005). Conclusion: The findings reinforce the systemic pro-inflammatory phenotype reported in elderly by demonstrating an increased phase-1 activation of inflammasomes in PBMC of vascular patients. [ABSTRACT FROM AUTHOR]

Colorectal cancer is the third most commonly diagnosed cancer worldwide. Although surgery remains the best treatment for this disease, adjuvant chemotherapy and radiotherapy are also very important in clinical practice. However, the notorious refractory lack of responses to radiochemotherapy greatly limits the application of radiochemotherapy in the context of colorectal cancer. There is a growing interest in the role that Aurora B may play in colorectal cancer cell survival as well as other cancer subtypes. In the current study, we sought to ascertain whether blocking of Aurora B signaling machinery by a small molecule inhibitor, CCT137690, could synergize radiation-induced colorectal cancer cell death. Results showed that CCT137690 increases the sensitivity of SW620 cells to radiation. Mechanistic studies revealed that Aurora B-Survivin pathway may be involved in this synergistic effect. Taken together, our results for the first time show that Aurora B inhibition and radiation exert a synergistic effect, resulting in enhanced colorectal cancer cell death. This synergistic effect is clinically relevant as lower doses of radiation could be used for cancer treatment, and could provide significant clinical benefits in terms of colorectal cancer management, while reducing unwanted side-effects. [ABSTRACT FROM AUTHOR]

An organocatalyzed one-pot Michael addition and Pictet-Spengler sequence utilizing b-keto amide and aliphatic a,bunsaturated aldehydes was developed, which provided access to highly substituted indolo[2,3-a]quinolizidines as a mixture of keto and enol tautomers. Such tautomeric pairs were transformed into stable compounds with an E-ethylidenyl group in telescoped steps. This method was successfully applied in the synthesis of epi-geissoschizol. [ABSTRACT FROM AUTHOR]

An expedient diastereoselective synthesis of highly functionalized indolo[2,3-α]quinolizidines adopting a cisH2/H12b geometry has been realized by a Pictet−Spengler/lactamization cascade sequence. The absolute stereochemistry at C2, C3, and C12b was governed by the originally created chirality of the Michael adduct through organocatalyzed conjugate addition of dialkyl malonates to α,β-unsaturated aldehydes. [ABSTRACT FROM AUTHOR]

A coarse-grain (CG) algorithm is developed for molecular dynamics (MD) simulation of proteins in which the polypeptide backbone as well as side chains were mapped into spherical interaction centres. The force field parameters for non-bonded interaction between these centres (beads) were evaluated from the interaction of all atoms corresponding to these beads using pairwise additivity. The validity of CG algorithm was demonstrated by comparing the potential energy, radius of gyration (RG), end-to-end distance and root-mean-square deviation with those obtained by all-atom (AA) simulation for a small protein molecule Trp-cage as well as for lysozyme in solution. The CG simulation for lysozyme in solution requires less than 1/50 CPU-time compared to that for the AA method. Also, the CG method converges to equilibrium potential energy much faster than AA simulation. CG simulation for lysozyme adsorbed on silica surface showed that the molecule is more unfolded with a less compact tertiary structure compared to that in the solution (with higher RG, end-to-end distance and the projected area on silica surface), this effect being more pronounced at higher temperature. A higher ionic strength resulted in a more extended structure for the lysozyme on silica surface. [ABSTRACT FROM AUTHOR]

Nanoparticles possess unique properties as a result of their large surface area per unit volume and therefore can be functionalized by the immobilization of enzymes for a variety of biosensing applications. Changes in the tertiary conformation of -lactoglobulin adsorbed on 90 nm silica nanoparticles with time were inferred using tryptophan fluorescence and Fourier transform infrared spectroscopy (FTIR) for different surface concentrations, temperature, pH, ionic strength, and 2,2,2-trifluoroethanol (TFE) and dithiothreitol (DTT) concentrations. Rapid initial unfolding followed by a much slower rate at longer times was observed, with the extent of unfolding being higher at lower surface concentrations, higher ionic strengths, higher temperature, higher TFE and DTT concentrations, and pI. The effect of temperature on the unfolding of adsorbed protein on the nanoparticle surface was similar to that in the bulk even though the extent of unfolding was higher for adsorbed protein molecules. The results of the extent of change in tertiary conformation using FTIR as indicated by the change in the ratio of amide II‘/amide I were consistent with those obtained by tryptophan fluorescence whereas the rates of conformational changes given by FTIR were found to be much faster. Circular dichroism (CD) spectra showed that altering the surface concentration by itself did not change the secondary structure of -lactoglobulin on the surface. TFE was found to increase the helix content at the expense of the fraction of the sheet, whereas the sheet was converted to an unordered conformation in the presence of DTT. [ABSTRACT FROM AUTHOR]

The nucleocapsid protein (N protein) is one of the major virion structural proteins of a newly identified coronavirus, which has been confirmed as the causative agent of severe acute respiratory syndrome (SARS). The major function of N protein is to assemble the RNA of coronavirus. in the present study, the gene encoding the N protein was cloned and the protein was expressed, purified, and refolded as shown by ¹H NMR measurement. The maximal Trp emission wavelength occurs near 331 nm, suggesting substantial burial of Trp residues. Circular dichroism measurements indicate that N protein contains little a-helical structure. Acid titration shows that N protein begins to unfold near pH 5 and is fully denatured near pH 2.7, and the acid unfolding process is reversible. The physical and chemical properties of N protein indicate that its stability is low. N protein is denatured reversibly at pH 7.4 either by urea (with Cm of 2.77 M and m value of 2.74 kcal mol-1 M-1) or GdmCl (with Cm of 1.46 M and m value of 4.50 kcal mol-1 M-1). In the heat-induced denaturation in phosphate-buffered saline buffer, N-protein starts to unfold at 35 °C and is completely denatured at 55 °C, where SARS virus was also reported to be inactivated. We propose that the low stability of N protein may be critical for the stability and function of SARS virus. [ABSTRACT FROM AUTHOR]

Endostatin is a potent angiogenesis inhibitor. The structure of endostatin is unique in that its secondary structure is mainly irregular loops and β-sheets and contains only a small fraction of α-helices with two pairs of disulfide bonds in a nested pattern. We choose human endostatin as a model system to study the folding mechanism of this kind. Nuclear magnetic resonance (NMR), tryptophan emission fluorescence, and circular dichroism (CD) were used to monitor the unfolding process of endostatin upon acid titration. Urea-induced unfolding was used to measure the stability of endostatin under different conditions. Our results show that endostatin is very acid-resistant; some native structure still remains even at pH 2 as evidenced by ¹H NMR. Trifluoroethanol (TFE) destabilizes native endostatin, while it makes endostatin even more acid-resistant in the low pH region. Stability measurement of endostatin suggests that endostatin is still in native structure at pH 3.5 despite the decreased stability. Acid-induced unfolding of endostatin is reversible, although it requires a long time to reach equilibrium below pH 3. Surprisingly, the α-helical content of endostatin is increased when it is unfolded at pH 1.6, and the α-helical content of the polypeptide chain of unfolded endostatin increases linearly with TFE concentration in the range of 0-30%. This observation indicates that the polypeptide chain of unfolded endostatin has an intrinsic α-helical propensity. Our discoveries may provide clues for refolding endostatin more efficiently. The acid-resistance property of endostatin may have biological significance in that it cannot be easily digested by proteases in an acidic environment such as in a lysosome in the cell. [ABSTRACT FROM AUTHOR]

Cascading failures in the internet have attracted recent attention due to their unpredictability and destructive consequences. Exploring the failure behavior patterns is necessary because they can provide effective intervention approaches to prevent huge network disasters. To analyze internet flow behaviors during cascading failures (chain reactions in router and link failures), we characterize the internet as two coupled networks, the router network and the flow network. Here the flow network is an abstract representation of data correlations obtained from the router network. We use this coupled network to build a cascading failure model for studying flow transmission and competition, which is reflected in bandwidth competition given by limited link capacity. We first study the dependency between routers and flows to explore the flow transmission efficiency when a failure event occurs. Moreover, we find that rerouting enables flow competition area (the number of flows with which one flow has a competitive relationship) to initially remain stable during a failure episode, but that it then quickly drops due to poor physical network connectivity. Additionally, in the early stage after the failure event, the degree of flow competition sharply increases because of the growing number of the flows and congestion. Subsequently, the flow competition decreases due to the failure of flow transmission. [ABSTRACT FROM AUTHOR]

In this study, using high-speed mechanical drilling on printed circuit boards (PCBs) with two micro carbide drill bits with diameters of 0.15 mm and 0.20 mm, two different PCB micro-cylinder array inserts are fabricated using the micro-ultrasonic powder moulding (micro-UPM) process. According to the temperature curves recorded by a measurement module, when viscoelastic heating dominated, the temperature increasing rate was about three times the rate when interfacial friction heating dominated. From the differential scanning calorimetry and nanoindentation test results, if the ultra-high molecule weight polyethylene (UHMWPE) powder was not preheated, then the micro-cylinder array polymer parts generally consisted of nascent and melt-recrystallised phases as a whole. However, when the micro-cavity and compressed UHMWPE powder grew from room temperature of 28 °C to 85 °C, the two-phase structure gradually developed into a single melt-recrystallised phase. According to single-crystal x-ray diffraction test results, the crystallinity of the base region of the micro-UPM cylinder array part is higher than that of the micro-cylinder region, whereas the grain size of the (1 1 0) crystal surface is larger than that of the (2 0 0) crystal surface. [ABSTRACT FROM AUTHOR]

The electrochemiluminesce (ECL) efficiency of luminous emitter can be enhanced by the means of electrochemiluminesce resonance energy transfer (ECL-RET) with a matched donor. However, generally, the donor and acceptor pairs were separated in different independent nanostructures, experiencing the challenging issues of limited energy transfer efficiency and luminous stability. Herein, we designed novel ECL-RET model within one nanostructure containing the donor of tris(4,4'-dicarboxylicacid-2,2'-bipyridyl) ruthenium(II) dichloride (Ru(dcbpy)32+) and the acceptor of CdSe@ZnS quantum dots (QDs) for acting as the ECL emitter (QDs-Ru(dcbpy)32+), which significantly reduced the energy loss and improved the ECL efficiency of QDs because of the short path of energy transmission. To demonstrate the proof-of-concept, the proposed QDs-Ru(dcbpy)32+ was employed to construct a new kind of ECL biosensor that could achieve the ultrasensitive detection of microRNA-141 (miRNA-141) combining target recycling amplification and the double-output conversion strategies. Notably, the proposed double-output conversion strategy enabled a small number of miRNA to be successfully transferred into a large number of reporter DNA which could capture numerous QDs-Ru(dcbpy)32+-labeled signal probes on the sensing surface to realize the ECL response to the logarithm of the concentration of miRNA-141. With the ultrahigh-efficient ECL-RET in one nanostructure and the dual amplification including target recycling as well as double-output conversion strategies, the proposed biosensor realized ultrasensitive detection of miRNA-141 and performed the concentration range from 100 aM to 10 pM and the estimated detection limit was 33 aM (S/N = 3). Impressively, this method can sensitively detect the miRNA-141 of human prostate cancer cells and provide a significant boost for the detection of other biomarkers in early cancer diagnosis and therapeutic monitoring. [ABSTRACT FROM AUTHOR]

Switch semi-active control is introduced to improve the performance of the floating raft vibration isolation system on isolating vibration in the vicinity of the resonance frequency. A switch-controllable linear damper based on the electromagnetic damping principle is developed, whose characteristic parameters are obtained by experiment. The dynamic model of a semi-active control floating raft vibration isolation system is established, and two switch control algorithms are proposed. Algorithm 1 aims to minimize the kinetic energy of the raft, and Algorithm 2 balances minimizing the kinetic energy of the raft and minimizing the input energy of the system. The simulations of the original system, the system with the controllable damper, and the system with the damper controlled by the algorithms are carried out. The vibration acceleration responses of the foundation of the systems are used to evaluate the vibration isolation effect. The results show that the switching semi-active control using Algorithms 1 and 2 can significantly suppress the vibration of the system near the resonance frequency. Finally, the test platform of the switch's semi-active controlled floating raft vibration isolation system is built, and the simulation results are verified by the experimental result. [ABSTRACT FROM AUTHOR]

Lower extremity varicose veins are a common condition in vascular surgery and proliferation of vascular smooth muscle cells (VSMCs) in the intima is a significant pathological feature of varicosity. However, the pathogenesis of varicose veins is not fully understood. Osteopontin (OPN) could promote the migration and adhesion of VSMCs through the cell surface receptor integrin ß3 and the cooperation of OPN and integrin ß3 is involved in many vascular diseases. However, the role of OPN and integrin ß3 in varicosity remains unclear. In the current study, we found that the methylation levels in the promoter regions of OPN and integrin ß3 genes in the VSMCs of varicose veins are reduced and the protein expression of OPN and integrin ß3 are increased, compared with normal veins. Furthermore, it was observed that VSMCs in the neointima of varicose veins were transformed into the synthetic phenotype. Collectively, hypomethylation of the promoter regions for OPN and integrin ß3 genes may increase the expression of these genes in varicosity, which is closely related to VSMC phenotype switching. Hypomethylation of the promoter regions for OPN and integrin ß3 genes may be a key factor in the pathogenesis of varicosity. [ABSTRACT FROM AUTHOR]

Recently, the graphene-based absorber captures much attention due to its bright potential. In this paper, a modeling study of graphene-based absorber is made for variable magnetostatic bias, i.e., the magnetic circular dichroism (MCD). A strong MCD signal about ΔA=0.94 is obtained in 7 T for a uniform graphene-based absorber. By periodically patterning subwavelength holes on the graphene, the structured absorber exhibits two obvious peaks induced by cavity resonance and localized resonance of meta-surface in 0 T, respectively. As the magnetic field increases, the absorption peaks show quite different electromagnetic response for the two kinds of circularly polarized lights. Two distinct MCDs signals of 0.711 at 2.02 THz and 0.91 at 2.49 THz in 7 T are observed. The results are well explained by a modified equivalent circuit model. [ABSTRACT FROM AUTHOR]

This paper presents a singularity study on a special class of spatial cable-suspended parallel mechanisms (CSPMs) with merely three translational degrees of freedom using redundant actuators. This paper focuses on the CSPMs that have the capability to perform the purely translational movement with pairwise cables as parallelograms. There are two types of singularity to be discussed, which result from dynamic equations of CSPMs and the parallelogram constraint of pairwise cables. To ensure three-translational dofs without rotation of the end-effector, the matrix formed by normals of the planes based on each pairwise cables should maintain in full rank. In the case study, four typical designs of CSPMs with a planar end-effector and a spatial end-effector are discussed to clarify and conclude the singularity features of CSPMs with actuation redundancy. The results show that for some architectures there exist both types of singularity for redundantly actuated CSPMs with pairwise cables but for some other architectures the redundant actuation exerts no effect on the singularity issue. [ABSTRACT FROM AUTHOR]

We studied phenotypic variation among provenances of Liriodendron at near-mature stage to identify those with the most desirable traits for production. To provide a scientific basis for the selection of superior provenances of Liriodendron, a provenance trial was established with five provenances of Liriodendron tulipifera and 15 provenances of Liriodendron chinense. This trial was established in 1992 at the Subtropical Experimental Center in the Chinese Academy of Forestry. The growth, stem-form qualities, and wood basic density of each provenance were investigated in December 2015. The findings indicated that the growth traits of Liriodendron possess significant genetic differences in terms of interaction between provenance and site. Analysis of growth related traits revealed that the choice of fast-growing provenances might improve trunk straightness but decrease the wood basic density. Ring width variance analysis showed that the variation coefficients increased for ring width of four 5-year ring segments between provenances, but the width decreased from pith to cambium, which suggested genetic improvement of wood productivity and density could be realized by provenance selection. Monan (MN) of Guizhou Province and Fuyang (FY) of Zhejiang Province were selected as two high-yield and high-quality provenances based on the analysis of radial variation patterns. [ABSTRACT FROM AUTHOR]

A decarboxylative formal [4 + 2] cycloaddition reaction between ethynyl benzoxazinanones and 5-substituted 2-silyloxyfurans catalyzed by chiral Cu–Pybox complex is described. This method allows the formation of intriguing tetrahydroquinolines fused with a butyrolactone moiety featuring three contiguous chiral centers in high yields with excellent diastereo- and enantioselectivities in most cases. The utility of this method was exemplified by the removal of the N-protecting groups and derivatization on the terminal alkyne functionality of the cyclization products. [ABSTRACT FROM AUTHOR]

Ongoing efforts to remove pathological inflammatory stimuli are crucial for the protection of endothelial cells in diabetes. Nerve injury-induced protein 1 (Ninj1) is an adhesion molecule that not only contributes to inflammation but also regulates the apoptosis of endothelial cells. In the present study, Ninj1 was found highly expressed in endothelial cells in Type 2 diabetic mice and increased in high-glucose (HG) cultured HUVECs. Furthermore, we found that Ninj1 levels are up-regulated in endothelial cells in clinical specimens of diabetic patients when compared with nondiabetic tissues, indicating a biological correlation between Ninj1 and endothelial pathophysiology in diabetic condition. Functional blocking of Ninj1 promoted endothelial tube formation and eNOS phosphorylation in the HG condition. Additionally, blocking Ninj1 inhibited the activation of caspase-3 and increased the Bcl-2/Bax ratio, thus inhibiting HUVECs apoptosis induced by HG. HG-induced ROS overproduction, p38 MAPK and NF-κB activation, and the overexpression of VCAM-1, ICAM-1, MCP-1, and IL-6 genes were ameliorated after Ninj1 was blocked. Using the signaling pathway inhibitor LY294002, we found that Bcl-2 expression and eNOS phosphorylation after Ninj1 blockade were regulated via PI3K/Akt signaling pathway. The in vivo endothelial contents, α-SMA+PECAM-1+ vascular numbers, and blood perfusion in the hindlimb were markedly up-regulated after Ninj1 was blocked. According to our findings, functional blocking of Ninj1 shows protective effects on diabetic endothelial cells both in vitro and in vivo. Thus, we consider Ninj1 to be a potential therapeutic target for preventing endothelial dysfunction in diabetes mellitus. [ABSTRACT FROM AUTHOR]

This paper discusses the tracking coordination of a linear switched reluctance machine (LSRM) network based on a global feedback control strategy with a full-state observation framework. The observer is allocated on the follower instead of the leader to form a leader--follower--observer network, by utilizing the leader as the global feedback tracking controller and the observer as the observation of the full states. The internal model compensator (IMC) is applied to the leader for the improvement of the network performance. The full-state information of the LSRM network is reconfigured by the output of the LSRM where the observer is located to provide necessary feedback information to the leader. Then, the controllability and observability of the leader--follower--observer network with the IMC are inspected, serving as a basis for the design of the global controller with the IMC and full-state observer. Experimentation verifies the effectiveness of the proposed network control scheme and the results demonstrate that both the absolute and the relative accuracy can be simultaneously improved, compared to the LSRM network with only the consensus algorithm and no global feedback mechanism. [ABSTRACT FROM AUTHOR]

This paper investigates the controllability of a closed-loop tracking synchronization network based on multiple linear-switched reluctance machines (LSRMs). The LSRM network is constructed from a global closed-loop manner, and the closed loop only replies to the input and output information from the leader node. Then, each local LSRM node is modeled as a general second-order system, and the model parameters are derived by the online system identification method based on the least square method. Next, to guarantee the LSRM network's controllability condition, a theorem is deduced that clarifies the relationship among the LSRM network's controllability, the graph controllability of the network and the controllability of the node dynamics. A state feedback control strategy with the state observer located on the leader is then proposed to improve the tracking performance of the LSRM network. Last, both the simulation and experiment results prove the effectiveness of the network controller design scheme and the results also verify that the leader-based global feedback strategy not only improves the tracking performance but also enhances the synchronization accuracy of the LSRM network experimentally. [ABSTRACT FROM AUTHOR]

A fuzzy position controller is employed for the linear switched reluctance motor. Performance comparison between the fuzzy controller and a proportional-differential (PD) controller is carried out. Under the PD controller, the absolute steady-state error is 44.5 ~211.5 μm under normal condition and 1157–1212 μm under sustained time-variant disturbance circumstance, respectively. The absolute steady-state error of 3 μm and 9 μm can be achieved under the fuzzy controller in the normal and sustained disturbed circumstance. Experimental results demonstrate that the position tracking performance from the proposed algorithm is superior to the conventional PD control strategy, both in normal circumstance and disturbance environment. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease is characterized by the accumulation of amyloid beta (Aβ) and the formation of neurofibrillary tangles. Aβ is the main constituent of senile plaques and is largely involved in neuronal death and neuroinflammation. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) is one of the main transcriptional coactivator and has been related to many fields such as energy metabolism, cardiovascular disease, neurodegenerative disorders, and so on.Results: Treatment with Aβ1-42 reduced the expression of PGC-1α in both protein and RNA levels of neuroblastoma N2a cells. Aβ1-42 induced a robust activation of cleaved caspase-3 while PGC-1α suppressed this activation and protected N2a cells from Aβ-induced cell death. Overexpression of PGC-1α significantly reduced the level of main proinflammatory cytokines. In addition, PGC-1α inhibited the transportation of NF-κB p65 from cytoplasm to nucleus and IκBα degradation induced by Aβ1-42.Conclusion: Our results have demonstrated that PGC-1α can protect neuroblastoma cells against Aβ-induced neuronal death and neuroinflammation. Moreover, this neuroprotective effect of PGC-1α is regulated through NF-κB pathway. Taken together, our work provides evidence that PGC-1α could be beneficial in targeting Aβ neurotoxicity. [ABSTRACT FROM AUTHOR]

Colorectal cancer is currently the third most common cancer in males and the second in females worldwide. In spite of marked progress having been achieved in surgical resection, radiotherapy and chemotherapy, the prognosis for patients with colorectal cancer remains poor. Previous studies have demonstrated that the abnormal expression of microRNAs contributed to human cancer carcinogenesis and progression, suggesting miRNAs as novel therapeutic targets in colorectal cancer. The aim of the present study was to investigate the expression, functions and underlying molecular mechanisms of microRNA-184 (miR-184) in colorectal cancer. The results identified that miR-184 was significantly downregulated in colorectal cancer tissues and cell lines. In vitro functional studies demonstrated that miR-184 significantly inhibited colorectal cancer cell proliferation, migration and invasion. Notably, insulin-like growth factor 1 receptor (IGF-1R) was identified as a direct target of miR-184 in colorectal cancer. Furthermore, the functions of IGF-1R small interfering RNA were similar to those induced by miR-184 in colorectal cancer, suggesting IGF-1R as a functional target of miR-184 in colorectal cancer. The results of the present study indicated that miR-184 may be a novel therapeutic strategy regimen of targeted therapy for colorectal cancer. [ABSTRACT FROM AUTHOR]

This paper investigates a distributed, coordinated motion control network based on multiple direct-drive, linear switched reluctance machines (LSRMs). A hierarchical, two-level synchronization control strategy is proposed for the four LSRMs based motion control network. The high-level, reference signals agreement algorithm is first employed to correct the asynchronous behaviors of the position commands. Then, the low-level tracking synchronization method is applied for the collaborative position control of the four LSRMs. The proposed two-level, fault-tolerant control strategy eliminates the asynchrony of the reference signals and it also guarantees the coordinated tracking control performance of the four LSRMs. Experimental results demonstrate that effective coordinated tracking control can be ensured, based on the successful agreement of reference signals and an absolute tracking error falling within 2 mm can be achieved. [ABSTRACT FROM AUTHOR]

Asymmetric 1,6-addition of malonates to para-quinone methides has been developed by using amide-phosphonium salts derived from easily available chiral α-amino acids as bifunctional phase transfer catalysts. Stabilized para-quinone methides with various substituents on the phenyl ring were reacted with diphenyl malonates to give functionalized diaryl methines in excellent yields and high to excellent ee's. Furthermore, to show the utility of this methodology, a gram scale synthesis of an 1,6-addition adduct and its further elaboration into the key intermediate for synthesis of GPR40 agonists were also described. [ABSTRACT FROM AUTHOR]

The understanding of various types of disorders in atomically thin transition metal dichalcogenides (TMDs), including dangling bonds at the edges, chalcogen deficiencies in the bulk, and charges in the substrate, is of fundamental importance for TMD applications in electronics and photonics. Because of the imperfections, electrons moving on these 2D crystals experience a spatially nonuniform Coulomb environment, whose effect on the charge transport has not been microscopically studied. Here, we report the mesoscopic conductance mapping in monolayer and few-layer MoS2 field-effect transistors by microwave impedance microscopy (MIM). The spatial evolution of the insulator-to-metal transition is clearly resolved. Interestingly, as the transistors are gradually turned on, electrical conduction emerges initially at the edges before appearing in the bulk of MoS2 flakes, which can be explained by our firstprinciples calculations. The results unambiguously confirm that the contribution of edge states to the channel conductance is significant under the threshold voltage but negligible once the bulk of the TMD device becomes conductive. Strong conductance inhomogeneity, which is associated with the fluctuations of disorder potential in the 2D sheets, is also observed in the MIM images, providing a guideline for future improvement of the device performance. [ABSTRACT FROM AUTHOR]

The dielectric constant or relative permittivity (εr) of a dielectric material, which describes how the net electric field in the medium is reduced with respect to the external field, is a parameter of critical importance for charging and screening in electronic devices. Such a fundamental material property is intimately related to not only the polarizability of individual atoms but also the specific atomic arrangement in the crystal lattice. In this Letter, we present both experimental and theoretical investigations on the dielectric constant of few-layer In2Se3 nanoflakes grown on mica substrates by van der Waals epitaxy. A nondestructive microwave impedance microscope is employed to simultaneously quantify the number of layers and local electrical properties. The measured εr increases monotonically as a function of the thickness and saturates to the bulk value at around 6-8 quintuple layers. The same trend of layer-dependent dielectric constant is also revealed by first-principles calculations. Our results of the dielectric response, being ubiquitously applicable to layered 2D semiconductors, are expected to be significant for this vibrant research field. [ABSTRACT FROM AUTHOR]

Thefirst copper-catalyzed enantioselective propargylation of trialkylmethantricarboxylate with propargylic alcohol derivatives was developed.The tricarboxylate unit in the obtained adducts could be easily transformedinto a malonate moiety by treating with in situgeneratedNaOEt in excellent yield without racemization. [ABSTRACT FROM AUTHOR]

Grassland degradation and grassland use type changes are associated with dynamics in soil properties and biogeochemical cycling, with implications for carbon and nitrogen cycling and trace gas fluxes. To examine the influence of grassland degradation and grassland use type changes on gases fluxes, emissions of CO2, CH4 and N2O were measured in three alpine ecosystems (alpine meadow, alpine steppe and alpine desert) with healthy and degraded grasslands on the Qinghai-Tibetan Plateau in May, August and October 2013. The lowest CO2, CH4 and N2O fluxes occurred in alpine deserts, and the highest fluxes occurred in alpine steppe. In general, degraded grasslands had relatively higher gas fluxes than healthy grasslands, except for CH4 dynamics. The temporal variation in gas fluxes indicated that CO2 and N2O fluxes were highest in August and lowest in May, while the lowest fluxes of CH4 were in August. Stepwise linear analysis was employed to explore the key factors for different gas fluxes. In alpine meadow and alpine steppe, the variation in CO2 and N2O fluxes in August could be explained by soil temperature and soil water content, while in May and October, soil physical and chemical properties, including soil pH, clay content and -NO3NO3--N, were the key factors. Soil water content and +NH4NH4+-N contributed to the CH4 fluxes. However, in alpine desert, soil water content was the key factor affecting gas emissions for different experimental sites. These results indicate that the examined alpine grasslands emitted a large amount of gas emissions especially after the grassland had degraded; therefore, more attention should be paid to protecting grassland degradation in the Qinghai-Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Background: Although studies of self-rated health (SRH) are conducted widely in developed countries, comprehensive assessments of the determinants of SRH in Chinese are scarce, particularly for working Chinese individuals. Determinants of SRH might differ among worksites based on differences in the nature and stress associated with different jobs, work intensity, and the lifestyles of employees. Methods: Two thousand and forty questionnaires that addressed SRH, demographic characteristics, lifestyle, and the psychosocial work environment were administered to employees at two worksites. A total of 1644 subjects provided complete data for analysis (80.6% response rate). Results: Participants from government departments had significantly better SRH than did those from high-tech enterprises (61.1% vs. 67.5%, respectively). Lifestyles were significantly less healthy at government departments compared with high-tech enterprises, whereas the psychosocial work environment was better. The results of unadjusted and adjusted models revealed differences between the potential health-influencing factors of participants based on their type of worksite. In logistic regression models, gender was strongly associated with SRH in all participants, whereas length of service was correlated with SRH only in participants from high-tech enterprises. In high-tech enterprises, good SRH was less common in physically inactive subjects vs. physically active participants (OR = 0.561). In government departments, passive smoking was negatively associated with SRH significantly. Social capital (OR = 1.073) and job control (OR = 1.550) were positively correlated with SRH in high-tech enterprises. Job control was the only psychosocial factor significantly associated with SRH in government departments. Conclusions: Participants from different types of worksite reported different SRH, healthy lifestyles, and psychosocial work environments. Moreover, the association between SRH and demographic characteristics, lifestyle, and the psychosocial work environment significantly differed by type of worksite. [ABSTRACT FROM AUTHOR]

We have developed a highly efficient cascade sequence for asymmetric synthesis of indoloquinolizidines with absolute control of cis-H2/H12b relative geometry in good to excellent yields and excellent enantioselectivities. This cascade was triggered by the Ru(ll)-TsDPEN-catalyzed asymmetric transfer hydrogenation of imino diesters, with subsequent spontaneous lactaniization with discrimination between the two diastereotopic 2-allcoxy-2-oxoethyl groups. The synthetic utility of this strategy was demonstrated by the asymmetric preparation of dihydrocorynantheol, geissaschizol, and isogeissoschizol. [ABSTRACT FROM AUTHOR]