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Obstructive sleep apnea syndrome (OSAS) causes recurrent apnea and intermittent hypoxia at night, leading to several complications such as cognitive dysfunction. However, the molecular mechanisms underlying cognitive dysfunction in OSAS are unclear, and oxidative stress mediated by intermittent hypoxia is an important mechanism. In addition, the improvement of cognitive dysfunction in patients with OSAS varies by different treatment regimens; among them, continuous positive airway pressure therapy (CPAP) is mostly recognized for improving cognitive dysfunction. In this review, we discuss the potential mechanisms of oxidative stress in OSAS, the common factors of affecting oxidative stress and the Links between oxidative stress and inflammation in OSAS, focusing on the potential links between oxidative stress and cognitive dysfunction in OSAS and the potential therapies for neurocognitive dysfunction in patients with OSAS mediated by oxidative stress. Therefore, further analysis on the relationship between oxidative stress and cognitive dysfunction in patients with OSAS will help to clarify the etiology and discover new treatment options, which will be of great significance for early clinical intervention. [ABSTRACT FROM AUTHOR]

Pyruvate kinase M2 (PKM2) is a key rate-limiting enzyme in glycolysis. It is well known that PKM2 plays a vital role in the proliferation of tumor cells. However, PKM2 can also exert its biological functions by mediating multiple signaling pathways in neurological diseases, such as Alzheimer's disease (AD), cognitive dysfunction, ischemic stroke, post-stroke depression, cerebral small-vessel disease, hypoxic-ischemic encephalopathy, traumatic brain injury, spinal cord injury, Parkinson's disease (PD), epilepsy, neuropathic pain, and autoimmune diseases. In these diseases, PKM2 can exert various biological functions, including regulation of glycolysis, inflammatory responses, apoptosis, proliferation of cells, oxidative stress, mitochondrial dysfunction, or pathological autoimmune responses. Moreover, the complexity of PKM2's biological characteristics determines the diversity of its biological functions. However, the role of PKM2 is not entirely the same in different diseases or cells, which is related to its oligomerization, subcellular localization, and post-translational modifications. This article will focus on the biological characteristics of PKM2, the regulation of PKM2 expression, and the biological role of PKM2 in neurological diseases. With this review, we hope to have a better understanding of the molecular mechanisms of PKM2, which may help researchers develop therapeutic strategies in clinic. [ABSTRACT FROM AUTHOR]

Firms are seeking effective ways to cultivate high-value patents to support the goals of their innovative development, which has raised a promising research issue on different paths to high-value patents. However, prior studies mainly focused on the individual impact of a single or multiple patent attribute(s) on patent value. This study aims to explore the interactions of different patent attributes and their joint effect on high-value patents in the emerging economy context using three-dimensional patent value as the research lens. Using data from patents that won China Patent Awards as high-value patent samples and the fuzzy-set Qualitative Comparative Analysis (fsQCA), this study examines the relationships between three-dimensional patent attributes of technological, legal and economic value and high-value patents. The results demonstrate that the interactions of three-dimensional patent attributes are prerequisites for high-value patents, and four configuration paths contribute to China's high-value patents. By interpreting multiple patent attribute interactions, this study further reveals the technological-economic complementary mechanism and the potential substitution mechanism within and among the three-dimensional patent attributes in high-value patents, and draws out implications for research, policy and practice. This study contributes to the patent value literature by adopting a configurational perspective to examine the causal complexity of patent attribute combinations, and providing a systematic understanding of the effective configuration paths to high-value patents in China as well as the complementary and substitution mechanisms between patent attributes. The findings also support better-informed patent policy and firm strategies aimed at gaining more high-value patents. [ABSTRACT FROM AUTHOR]

In the milling of CFRP, the most widely used cemented carbide tool is vulnerable to severe wear. Focusing on the issue, the study aims to reduce the tool wear extent by the way of designing high-performance tool structure. A calculation method of tool wear volume is established, characterized by considering the dynamic influences of temperature variation in the continuous milling process on the hardness of tool surface. With the method, the anti-wear performance of the micro cutting edge and the integrated cutting edge which are most commonly used in machining of CFRP is analyzed, under an error within 12%. It is indicated that the anti-wear performance of the integrated cutting edge is much better than the micro cutting edge, while the latter one has the inherent advantage of effectively removing the material of CFRP. Based on this, a hybrid tool structure which takes advantage of both the two types of cutting edge is proposed. Results of tool life test suggest that the tool life of the proposed tool is about 300% over than that of multitooth tool. [ABSTRACT FROM AUTHOR]

The main aim of the current work was to explore the differential metabolites and differentially expressed genes of longissimus dorsi muscle (LDM) between castrated and uncastrated fattening male South Sichuan black goats (Capra hircus). Then, the key genes regulating important differential metabolites (DMs) in castrated male goats were observed by integrated metabolomics and transcriptomics analyses. In addition, we evaluated the effects of castration on blood constituents, dressing percentage, and water holding capacity of LDM in male black goats. The results showed that the concentrations of alkaline phosphatase (ALP), total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) were significantly increased and testosterone was significantly decreased in castrated male goats compared with the uncastrated male goats, while dressing percentage of black goats and water holding capacity of longissimus dorsi muscle were not significant differences. Through metabolomics and transcriptomics analyses, 23 important KEGG pathways, 13 important DMs, 32 important differentially expressed genes (DEGs), and 13 key genes related to the “Metabolism” and “Organismal systems” pathways were screened. Lipid accumulation may be elevated in the blood of fattening South Sichuan black goats after castration. Castration might play a positive role in energy provision, intercellular signaling, muscle function, softening of meat, disease reduction, and anti-oxidation of LDM. P4HA2, AKR1B1, GPT2, L2HGDH, ENSCHIG00000021660, ENSCHIG00000023861, DGAT2, ULK1, SLC38A3, PLA2G4A, SLC6A1, ENSCHIG00000026624, and ND2 might be the key genes regulating important DMs in the KEGG pathways related to “Metabolism” and “Organismal systems” of castrated male goats compared with the uncastrated male goats. [ABSTRACT FROM AUTHOR]

The preparation quality of Ni-based single crystal alloy (NSCA) can be qualitatively reflected based on its surface defects. However, the quantitative expression of the preparation quality of NSCA is difficult to achieve. Accordingly, based on the surface defects of NSCA, molecular dynamics (MD) combined with ultrasound would be used to characterize the preparation quality of NSCA at the micro-level. In this study, the quantitative relationship between Λ (dislocation density) and L (dislocation chord length) has been established by using the second-harmonic Lamb wave, which can be used to characterize the state changes of surface defects (surface roughness and microcracks) of NSCA. In view of the limitations of experiment, MD has been further used to quantitatively calculate the change law of Λ and L, and then the change law of characteristic parameter in the experiment has been analyzed. This significance of the study is that it permits quantitative evaluation of the preparation quality of NSCA at the micro-level. [ABSTRACT FROM AUTHOR]

In recent years, many heavy metal ions have been discharged into the environment, which is threatening human health. Herein, the β-cyclodextrin-modified molybdenum disulfide composite (β-CD/MoS2) was prepared to adsorb Cr(VI) from water. The results demonstrated that the retention of Cr(VI) onto β-CD/MoS2 was dependent on pH and independent of coexisting ions. The removal capacity of β-CD/MoS2 for Cr(VI) reached 156.8 mg/g, and the removal process was endothermic. According to the characterization analysis, the uptake of Cr(VI) onto β-CD/MoS2 was governed by electrostatic attraction. Besides, the oxygen-containing groups were also responsible for the capture of Cr(VI). This work can offer new sight into the uptake of Cr(VI) from the ecological system. [ABSTRACT FROM AUTHOR]

A series of Li3Bi3Te2O12:xDy3+ (x = 0.01, 0.02, 0.05, 0.10, 0.15, 0.20, and 0.30 mol) samples were successfully prepared by high-temperature sintering method. The phase purities of the Li3Bi3Te2O12:Dy3+ phosphors were verified by powder X-ray diffraction (XRD) and revealed as single-phase structure. Under 386-nm excitation, the Dy3+-doped Li3Bi3Te2O12 phosphors show three emission peaks are located at 488, 579, and 673 nm, which are ascribed to the typical transitions from 4F9/2 to 6HJ/2 (J = 15, 13, and 11), respectively. The effects of concentration on luminescence properties indicate that the optimal doping concentration was x = 0.02 mol. The prepared Li3Bi3Te2O12:0.02Dy3+ phosphor has the excellent thermal stability with high-temperature quenching temperature (T0.5 > 480 K) and high activation energy (Ea = 0.38 eV). The shift of CIE chromaticity coordinates of Li3Bi3Te2O12:0.02Dy3+ phosphor with concentrations are Δx = 0.018 and Δy = 0.020. Thus, Li3Bi3Te2O12:Dy3+ phosphors have potential application for white light-emitting diodes (w-LEDs). [ABSTRACT FROM AUTHOR]

For the past few years, the environmental safety problems of radioactive nuclides caused wide public concern. In this work, the dodecyl trimethyl ammonium bromide-modified silicon dioxide composite (DTAB/SiO2) was synthesized for the elimination of uranium. The dodecyl trimethyl ammonium bromide can decorate the surface of the silicon dioxide and change its surface topography, which can offer more active sites and functional groups for the combination of U(VI). The removal capacity of U(VI) on DTAB/SiO2 reached 78.1 mg/g, which was greater than that of the silicon dioxide nanopowder. In the adsorption process, the surface oxygen-containing functional groups formed surface complexation with uranium. The results may provide helpful content to eliminate U(VI) and expand the application of surfactant in radioactive nuclide cleanup. [ABSTRACT FROM AUTHOR]

The development of dual-ion metal-free batteries is restricted by the strong self-discharge effect and dissolution of some anode active materials in the polar electrolyte. This in turn leads to low coulombic efficiency and discharge capacity loss. It is of great significance to alleviate this phenomenon through the redox reactions of polymeric active materials. In this study, a metal-free poly(anthraquinonyl sulfide)-graphite battery was constructed based on a pure N-butyl-N-methylpiperidinium bis(trifluoromethylsulfonyl)imide ionic liquid electrolyte. The cell had a discharge capacity of 70.5 mAh g−1 (0.1 C) and a capacity retention rate of 98.6% after 100 cycles, with a coulombic efficiency of 98.3% (1 C). Comparative studies proved that the self-discharge effect of poly(anthraquinonyl sulfide)-graphite batteries is weaker than that of some dual-graphite batteries. Cyclic voltammetry experiments revealed that the redox reaction was highly reversible. Most significantly, this type of poly(anthraquinonyl sulfide)-graphite batteries provides a new way for the design of metal-free dual-ion batteries with excellent long-term cycling performance and minimal self-discharge effect. [ABSTRACT FROM AUTHOR]

Objective: To investigate the variation in T2 at different zones of normal hip cartilage in children and the relationship between T2 value and age. Materials and methods: Nineteen children with 30 normal hip joints were evaluated with a coronal T2 mapping sequence at a 3-Tesla MRI system. The femoral cartilage and acetabular cartilage were firstly segmented by mask-based interactive method and then equally divided into eight and six radial sections, respectively. Moreover, each radial section was further divided into two layers referring to the superficial and deep halves of the corresponding cartilage. Cartilage T2 of these sections and layers were measured and subsequently analyzed. Results: There was a negative correlation between the T2 values in the hip cartilage and the age of children (rs < − 0.6, P1 < 0.05). Articular cartilage T2 increased at angles close to the magic angle (54.7°). Femoral cartilage and acetabular cartilage had a relatively shorter T2 in the radial sections near the vertex of the femoral head. The T2 values in superficial layers of both cartilages were significantly higher than those in deep layers (P < 0.05). Conclusion: The T2 value decreases as the cartilage developing into a more mature state. Cartilage T2 values in the weight-bearing areas are relatively low due to an increase of collagen density and the loss of interstitial water. The restriction of the water molecules by solid components in the deeper layer of cartilage may decrease the T2 values. [ABSTRACT FROM AUTHOR]

Network security is subject to malicious attacks from multiple sources, and intrusion detection systems play a key role in maintaining network security. During the training of intrusion detection models, the detection results generally have relatively large false detection rates due to the shortage of training data caused by data imbalance. To address the existing sample imbalance problem, this paper proposes a network intrusion detection algorithm based on the enhanced random forest and synthetic minority oversampling technique (SMOTE) algorithm. First, the method used a hybrid algorithm combining the K-means clustering algorithm with the SMOTE sampling algorithm to increase the number of minor samples and thus achieved a balanced dataset, by which the sample features of minor samples could be learned more effectively. Second, preliminary prediction results were obtained by using enhanced random forest, and then the similarity matrix of network attacks was used to correct the prediction results of voting processing by analyzing the type of network attacks. In this paper, the performance was tested using the NSL-KDD dataset with a classification accuracy of 99.72% on the training set and 78.47% on the test set. Compared with other related papers, our method has some improvement in the classification accuracy of detection. [ABSTRACT FROM AUTHOR]

Non-conductivity and volume expansion are the main factors hindering the development of SiO anode materials. To solve these problems, in this work, a bifunctional anode was prepared with sulfur-induced SiO embedded carbon nanofibers (SiO–S–CNFs) by the electrospinning method and followed by annealing. Benefitting from the good conductance of CNFs, SiO–S–CNFs showed fast kinetics during charging and discharging. The introduction of sulfur powder during annealing formed a porous CNFs skeleton, further increasing the specific surface area of CNFs and effectively inhibiting the volume expansion of SiO. The large specific surface area also increased the contact between the electrode and the electrolyte and exposed more reaction sites of SiO. Results show that the reversible capacity of the cell was 376 mAh g−1 after 500 cycles at 1 A g−1. The SiO–S–CNFs electrode exhibited a high reversible capacity of 598 and 204 mAh g−1 at current densities from 0.1 to 2 A g−1, respectively. This work offers a feasible and simple method to ameliorate the electrochemical stability of silicon-based composite LIBs electrodes. [ABSTRACT FROM AUTHOR]

Long cyclic stability and high rate performance have been the major challenges of lithium-ion batteries (LIBs). Composite metal oxides as a promising anode materials for LIBs have been studied extensively due to their high theoretical capacity, abundant reserves and large-scale production. Yet, their practical applications are seriously restricted by the volume change and poor conductivity. Herein, the ZnO/TiO2/C nanofibers with different mole ratios of Ti/Zn were successfully synthesized by electrospinning method. The ZnO/TiO2/C nanofibers with a Zn/Ti mole ratio of 1:1 exhibited the highest reversible capacity of 912 mAh g−1 after 500 cycles at 100 mA g−1. Meanwhile, the ZnO/TiO2/C nanofibers also possess an excellent rate capability even at a high current density up to 5 A g−1. The Coulombic efficiency of ZnO/TiO2/C nanofibers has been steady at around 100% regardless of rate and long cycle. The good electrochemical properties of ZnO/TiO2/C nanofibers with a Zn/Ti mole ratio of 1:1 may be attributed to the synergistic effect of C and the introduction of interface between ZnO and TiO2. Overall, the ZnO/TiO2/C nanofibers were demonstrated unexpectedly high specific capacity retention, high reversibility and excellent rate performance as the anode materials of LIBs. [ABSTRACT FROM AUTHOR]

High wear is the primary failure mechanism of Inconel 625 in mechanical parts. The surface modification is workable method to improve tribological performance of Inconel 625. In this paper, the groove-textured surfaces with different widths and pitches were prepared on the surfaces of Inconel 625 by electrical discharge machining technology. The Sn-Ag-Cu solid lubricant was deposited on the grooves. The synergistic effects of Sn-Ag-Cu solid lubricant and groove-textured surface on the tribological performance of Inconel 625 were studied. Results show that the groove-textured surface of Inconel 625 filled with Sn-Ag-Cu solid lubricant shows the lowest friction. Compared with the untextured sample, the friction coefficients of groove-textured sample with the groove density of 20% and the groove-textured sample with the groove density of 25% filled by Sn-Ag-Cu are reduced 35% and 48%, respectively. The textures can trap wear debris under the dry sliding condition. In addition, Sn-Ag-Cu alloys filled in the grooves supply the sufficient lubricant at the contact interface during the sliding process. The lubricating film on the contact surface is formed gradually, which is mainly due to the shear adaptability and low melting point of Sn-Ag-Cu alloy. It shows that deposition of Sn-Ag-Cu solid lubricant coating on the groove-textured surface is an effective way for improving the friction and wear performance of Inconel 625. [ABSTRACT FROM AUTHOR]

Improving the tribological performance of TC4 has far-reaching significance for its wide application in the field of automobile and robot. The lubricating behaviors of TC4 with mixed solid lubricant (Sn-Ag-Cu with TiC) filled into surface dimples (TAC) during dry rotary sliding were systematically investigated. The results show that TAC has better tribological properties than TC4 and TC4-P. It attributes to the synergistic effect of surface dimples and mixed solid lubricant. The mixed solid lubricant in dimples is easier to be extruded to the frictional interface. The uniform and wear-resistant lubricating layer containing SAC and TiC is formed on the worn surface of TAC, reducing the direct impact of counterpart ball on substrate material. The fluidity of SAC endows TAC with the ability of self-repairing. [ABSTRACT FROM AUTHOR]

Protein cysteine S-sulfenylation is an essential and reversible post-translational modification that plays a crucial role in transcriptional regulation, stress response, cell signaling and protein function. Studies have shown that S-sulfenylation is involved in many human diseases such as cancer, diabetes and arteriosclerosis. However, experimental identification of protein S-sulfenylation sites is generally expensive and time-consuming. In this study, we proposed a new protein S-sulfenylation sites prediction method SulSite-GTB. First, fusion of amino acid composition, dipeptide composition, encoding based on grouped weight, K nearest neighbors, position-specific amino acid propensity, position-weighted amino acid composition and pseudo-position specific score matrix feature extraction to obtain the initial feature space. Secondly, we use the synthetic minority oversampling technique (SMOTE) algorithm to process the class imbalance data, and the least absolute shrinkage and selection operator (LASSO) are employed to remove the redundant and irrelevant features. Finally, the optimal feature subset is input into the gradient tree boosting classifier to predict the S-sulfenylation sites, and the five-fold cross-validation and independent test set method are used to evaluate the prediction performance of the model. Experimental results showed the overall prediction accuracy is 92.86% and 88.53%, respectively, and the AUC values are 0.9706 and 0.9425, respectively, on the training set and the independent test set. Compared with other prediction methods, the results show that the proposed method SulSite-GTB is significantly superior to other state-of-the-art methods and provides a new idea for the prediction of post-translational modification sites of other proteins. The source code and all datasets are available at https://github.com/QUST-AIBBDRC/SulSite-GTB/. [ABSTRACT FROM AUTHOR]

Based on the microporous structure lubrication method, Ti6Al4V(TC4)-based self-lubricating composites (TC4-SAC) with microporous channels filled by lubricant Sn-Ag-Cu are prepared. The effects of microporous channel parameters on stress and deformation of TC4-SAC are analyzed by finite element method. In addition, the friction and wear behaviors of TC4-SAC with different microporous channel parameters are compared, and the self-lubricating mechanisms of TC4-SAC are also analyzed. The results show that microporous channel parameters have a significant influence on the mechanical and tribological performance of TC4-SAC. Moreover, when the vertical depth of microporous channel = 3.5 mm, the micropore pitch = 3 mm, and the micropore diameter = 0.8 mm, TC4-SAC can obtain the best mechanical property and self-lubricating characteristic. [ABSTRACT FROM AUTHOR]

To overcome the poor tribological performance of M50 and widen its working range under high temperature, M50-Sn-Ag-Cu composites with curved microchannels (MCCs) and straight microchannels (MCSs) were prepared by Laser Additive Manufacturing Technology, respectively. Tribological properties of M50-based composites were studied. The results showed that MCCs had the better tribological performance. At 25 °C-15 N-0.2 m/s, compared with MCSs, the average friction coefficient of MCCs at the stable friction stage was reduced by 10.7%. In contrast to MCSs, MCCs had a wider operating temperature range than MCSs, and the average friction coefficient of MCCs was decreased by 23.4 at.% 350-450 °C. According to the simulation results, the lubricant expansion of MCCs was 1.56 times that of MCSs at 400 °C. The curved microchannels design makes the storage and formation capacities of the lubricating film be enhanced without weakening the bearing capacity of MCCs. The two-way opening design of the curved microchannels could reduce the stress concentration between lubricant and friction interface, hence ensuring the efficient precipitation of lubricant. The research work could have a guiding role for widening the temperature range of M50 composites and improving the reliability of high-end equipment bearing. [ABSTRACT FROM AUTHOR]

Friction noise will not only affect the life of equipment, but also endanger human health. It is imperative to reduce the friction noise of mechanical system. Tribological properties and friction noise of Ti6Al4V alloy (TC4) and Ti6Al4V-4.6 wt.% MoS2-3.7 wt.% TiC (TMT) self-lubricating composites under 5, 10 and 15 N at 0.2 m/s are investigated using a self-built friction noise experimental apparatus. The results show that MoS2 and TiC have the good synergistic effects on tribological and friction noise performance. A lubricating film enriched with MoS2 is formed on the worn surface to reduce the stick–slip and surface roughness, and the energy of transition on the worn surface is reduced; hence, the friction noise is decreased. TiC can improve the hardness and wear resistance of TMT, and it supports the lubricating film to hinder the development of plowing grooves and peeling pits to a deeper level. The worn surface and friction noise performance of TMT are best at 10 N. This study has the far-reaching implications for improving the tribological properties and inhibiting friction noise of TC4 alloys. [ABSTRACT FROM AUTHOR]

Quasars, which are exceptionally bright objects at the centres (or nuclei) of galaxies, are thought to be produced through the accretion of gas into disks surrounding supermassive black holes1–3. There is observational evidence at galactic and circumnuclear scales4 that gas flows inwards towards accretion disks around black holes, and such an inflow has been measured at the scale of the dusty torus that surrounds the central accretion disk5. At even smaller scales, inflows close to an accretion disk have been suggested to explain the results of recent modelling of the response of gaseous broad emission lines to continuum variations6,7. However, unambiguous observations of inflows that actually reach accretion disks have been elusive. Here we report the detection of redshifted broad absorption lines of hydrogen and helium atoms in a sample of quasars. The lines show broad ranges of Doppler velocities that extend continuously from zero to redshifts as high as about 5,000 kilometres per second. We interpret this as the inward motion of gases at velocities comparable to freefall speeds close to the black hole, constraining the fastest infalling gas to within 10,000 gravitational radii of the black hole (the gravitational radius being the gravitational constant multiplied by the object mass, divided by the speed of light squared). Extensive photoionization modelling yields a characteristic radial distance of the inflow of approximately 1,000 gravitational radii, possibly overlapping with the outer accretion disk. Observations of highly redshifted broad absorption lines of helium and hydrogen atoms provide unambiguous evidence of fast infalling gas that is merging into an accretion disk around a black hole. [ABSTRACT FROM AUTHOR]

Ti6Al4V alloy has broad application prospects in the aircraft industry. However, when it is served as frictional motion components, the poor friction and wear properties may greatly influence the reliability and working life of the entire mechanical system. Therefore, this paper mainly investigates the tribological performance and self-repairing functionality of Ti6Al4V-multilayer graphene (MLG)-Ag composites (TMAC) from 25 to 600 °C. The results show that TMAC obtains better tribological behavior in comparison with Ti6Al4V alloy (TC4), Ti6Al4V-MLG composites (TMC) and Ti6Al4V-Ag composites (TAC). It should be ascribed to the synergistic action of the reinforcement MLG and lubricant Ag, which are crushed and spread out by mechanical and thermal stress in the friction process, leading to the formation of a lubricating film on the wear scar. Along with the spreading of lubricating film, Ag and MLG can precipitate onto the microdefective areas, thus playing an important role in repairing the wear scar of TMAC. [ABSTRACT FROM AUTHOR]

As one of the most widely used high-performance bearing steels, the service life of M50 steel is closely related to its tribological properties. In this paper, the dry sliding tribological tests of M50 matrix composite containing 5.0 wt.% Ag and 5.0 wt.% carbon fiber (CF) against Si3N4 ceramic balls are carried out under different applied loads. The morphologies and compositions of worn surfaces and the cross sections of worn scars are systematically characterized to explore the wear mechanisms. The results indicate that M50-Ag-CF composites (MAC) exhibit the excellent tribological properties at 10 N, whose friction coefficient and wear rate are 0.212 and 1.6 × 10−6 mm3 N−1 m−1, respectively. The excellent tribological performance can be attributed to the synergistic effect of Ag and CF. Massive Ag is enriched on the friction surface to form a lubricating film, thus reducing the surface roughness and friction coefficient. Meanwhile, CF acts as a reinforcement and improves the wear resistance of M50 matrix composites. [ABSTRACT FROM AUTHOR]

As an essential phosphate group hydrolase, alkaline phosphatase (ALP), whose level in serum is correlated with bone disease, liver dysfunction, and cancer, could be used as a biomarker for clinical diagnosis and biomedical studies. Hence, developing a convenient and sensitive method for ALP assay has importance in disease diagnosis, drug treatment, and prognosis assessment. In this work, using a hairpin DNA strand as the substrate, we developed an ultrasensitive and simple fluorescence method for quantitative ALP assay based on the binding difference of reduced graphene oxide (rGO) with different DNA strands coupled with λ exonuclease (λ exo) cleavage. Under the optimal conditions, the limit of detection (LOD) of ALP is estimated to be 0.01 U/L with the linear region from 0.5 U/L to 70 U/L. Furthermore, the proposed assay was used to detect ALP in complicated cell-free extracts and evaluate the inhibitory effects of two well-known inhibitors of ALP activity. Finally, the method was used to investigate the effect of natural compounds on ALP activity and five compounds with different inhibitory capability were screened. In summary, we propose that the new method for ALP assay can be applied for therapeutic drug monitoring (TDM) and high-throughput compound screening in combination with multiwell plate technology. [ABSTRACT FROM AUTHOR]

M50 steel is widely used in aero-engine bearings and other high-temperature bearings. However, the poor wear of M50 steel resistance restrains its further applications. In this paper, the sliding tribological behaviors of M50 steel, M50-Ag composites (MAC) and M50-Ag-TiC composites (MATC) against Si3N4 ball were investigated from 150 to 600 °C at 15 N-0.2 m/s. MATC showed better tribological properties in comparison with M50 and MAC. Especially at 450 °C, MATC obtained the lowest friction coefficient of 0.15 and smallest wear rate of 1.3 × 10−5 mm3 N−1 m−1. The excellent tribological performance of MATC during the friction test was attributed to the continuous lubricating film containing lubricant Ag and reinforcement TiC, as well as the subsurface compacted layer that could well support the lubricating film to prevent it from being destroyed. At 600 °C, because of the tribo-chemical reaction between Ag and Mo oxide during sliding process, the newly formed Ag2MoO4 lubricating film was well spread out on the friction surface, which could continuously improve the tribological behavior of MATC. This investigation was meaningful to improve the anti-friction and wear resistance of M50 matrix bearing over a wide temperature range. [ABSTRACT FROM AUTHOR]

M50 steel is widely applied to manufacture aircraft bearings where service lives are mainly determined by the friction and wear behaviors. The main purpose of this study is to investigate the tribological behaviors and wear mechanisms of M50-1.5 wt.% graphene composites (MGC) prepared by laser additive manufacturing (LAM) (MGC-LAM) sliding against Si3N4 ball from 25 to 550 °C at 18 N-0.2 m/s. XRD, EPMA, FESEM, and EDS mapping were conducted to understand the major mechanisms leading to the improvement in the sliding behavior of MGC-LAM. The results indicated that MGC-LAM showed the excellent friction and wear performance at 25-550 °C for the lower friction coefficient of 0.16-0.52 and less wear rate of 6.1-9.5 × 10−7 mm3 N−1 m−1. Especially at 350 °C, MGC-LAM obtained the best tribological performance (0.16, 6.1 × 10−7mm3 N−1 m−1). It was attributed to the dense coral-like microstructure, as well as the formed surface lubricating structure which is composed of the upper uniform lubricating film with massive graphene and the underneath compacted layer. [ABSTRACT FROM AUTHOR]

We have recently demonstrated the improved phase noise tolerance in coherent optical OFDM by digital coherent superposition of optical OFDM subcarriers, which are phase-conjugated pairs with Hermitian symmetry. In this approach, we realized DCS of OFDM subcarriers in single polarization (or channel), denoted as SP-DCS-OFDM. In this paper, we show that another approach is in dual polarizations, or DP-DCS-OFDM. According to the concept of phase-conjugated twin wave, both approaches can also mitigate the fiber nonlinearity to the first order. We prove that both approaches can cancel the inter-carrier interference (ICI) due to phase noise to the second order, and we derive the reduced ICI power to the fourth order using the Wiener phase noise model. In simulation, we show the enhanced tolerance to the laser phase noise and fiber nonlinearity. [ABSTRACT FROM AUTHOR]

In this paper, M(VO):Eu(M = Ca, Sr, Ba) phosphors have been synthesized by high-temperature solid-state method. The phase composition and luminescence properties of the synthesized phosphors were characterized by X-ray powder diffraction and photoluminescence (PL) spectra, respectively. The influences of fluxing agent and doped concentration of rare-earth ions on PL properties of the phosphor were investigated. The results indicated that the energy transfers between VO and Eu in the host occurred mainly via a dipole-dipole interaction mechanism. The increase in cation radius (from Ca to Ba) in the host causes the emission peak originated from D → F transition of Eu shifting from 615 to 621 nm, as well as decreasing the fluorescence lifetimes of Eu from 0.77 to 0.19 ms and changing the CIE chromaticity coordinates from the orange-red region to the white region. Moreover, the emission colors of Ba(VO): xEu can be firstly adjusted from cyan region to white light region via controlling the concentration of Eu. Temperature-dependent luminescence spectra proved the good thermal stability of the as-prepared phosphor. This work shows the potential application of europium-doped samples in UV converted pc-WLEDs. [ABSTRACT FROM AUTHOR]

Induced pluripotent stem cells (iPSCs) are an essential tool for modeling how causal genetic variants impact cellular function in disease, as well as an emerging source of tissue for regenerative medicine. The preparation of somatic cells, their reprogramming and the subsequent verification of iPSC pluripotency are laborious, manual processes limiting the scale and reproducibility of this technology. Here we describe a modular, robotic platform for iPSC reprogramming enabling automated, high-throughput conversion of skin biopsies into iPSCs and differentiated cells with minimal manual intervention. We demonstrate that automated reprogramming and the pooled selection of polyclonal pluripotent cells results in high-quality, stable iPSCs. These lines display less line-to-line variation than either manually produced lines or lines produced through automation followed by single-colony subcloning. The robotic platform we describe will enable the application of iPSCs to population-scale biomedical problems including the study of complex genetic diseases and the development of personalized medicines. [ABSTRACT FROM AUTHOR]

Human peripheral blood and umbilical cord blood represent attractive sources of cells for reprogramming to induced pluripotent stem cells (iPSCs). However, to date, most of the blood-derived iPSCs were generated using either integrating methods or starting from T-lymphocytes that have genomic rearrangements thus bearing uncertain consequences when using iPSC-derived lineages for disease modeling and cell therapies. Recently, both peripheral blood and cord blood cells have been reprogrammed into transgene-free iPSC using the Sendai viral vector. Here we demonstrate that peripheral blood can be utilized for medium-throughput iPSC production without the need to maintain cell culture prior to reprogramming induction. Cell reprogramming can also be accomplished with as little as 3000 previously cryopreserved cord blood cells under feeder-free and chemically defined Xeno-free conditions that are compliant with standard Good Manufacturing Practice (GMP) regulations. The first iPSC colonies appear 2-3 weeks faster in comparison to previous reports. Notably, these peripheral blood- and cord blood-derived iPSCs are free of detectable immunoglobulin heavy chain (IGH) and T cell receptor (TCR) gene rearrangements, suggesting they did not originate from B- or T- lymphoid cells. The iPSCs are pluripotent as evaluated by the scorecard assay and in vitro multi lineage functional cell differentiation. Our data show that small volumes of cryopreserved peripheral blood or cord blood cells can be reprogrammed efficiently at a convenient, cost effective and scalable way. In summary, our method expands the reprogramming potential of limited or archived samples either stored at blood banks or obtained from pediatric populations that cannot easily provide large quantities of peripheral blood or a skin biopsy. [ABSTRACT FROM AUTHOR]

Müller cells, the principal glial cells of the retina, play an important role in immune responses. Toll-like receptors (TLRs) are members of the pattern recognition receptor family and mediate innate and adaptive immune responses. In this study, we isolated, characterized Müller cells from mouse retina, and analyzed the expression of TLRs in these cells. We found that the mRNA of TLR2, TLR3, TLR4, and TLR5 was highly expressed by Müller cells. PAM3 and LPS, the agonists for TLR2 and TLR4, promoted Müller cells to produce the inflammatory cytokine Interleukine-6 and the chemokine MIP-2/CXCL2. These results suggest that Müller cells may be involved in innate and adaptive responses via TLR signaling in the eye. Our study should facilitate further study of the role of Müller cell in eye diseases and identification of the potential therapeutic targets. [ABSTRACT FROM AUTHOR]

CaF:Ce/Mn sub-micro cubes and nanospheres were successfully prepared through an ionic liquid-based hydrothermal method. OmimPF and OmimBF were utilized to introduce a new fluoride source and act as templates. The effects of ionic liquid amount and species on the morphologies and sizes of the nanocrystals have been studied. The photoluminescence properties of CaF:Ce/Mn sub-micro cubes have been discussed, and the results show that the emission intensity of Mn ions can be enhanced by co-doping with Ce ions through an efficient resonance-type energy transfer process. [ABSTRACT FROM AUTHOR]

Purpose To quantitatively evaluate aqueous flare and cells in patients with Behcet's disease. Methods This study included 30 Behcet's patients (52 eyes) with active uveitis. The patients were treated with immunosuppressive agents. Aqueous flare and cells were quantified using the laser flare-cell photometry before treatment and 1 and 2 months after treatment. Result Before treatment, mean aqueous flare (ph/ms) in Behcet's eyes was 25.7 ± 20.5. After treatment, flare values were significantly reduced after 1 and 2 months compared with those before treatment. No significant difference was found between flare values after 1 and 2 months. Before treatment, mean cell counts (cells/0.5 mm) in Behcet's eyes were 23.2 ± 29.4. After treatment, cell counts were also significantly reduced after 1 and 2 months compared with those before treatment. Cell counts were further significantly reduced from 1 to 2 months. Conclusion Both aqueous flare and cells were significantly increased in Behcet's patients with active uveitis and improved after a two-month treatment. Breakdown of the blood-aqueous barrier lasts longer than aqueous cells in these patients. [ABSTRACT FROM AUTHOR]

We present results of multi-epoch XMM-Newton observations separated by several years of the narrow-line Seyfert 1 (NLS1) galaxy, SDSS J160508.87+323921.4. The NLS1 showed X-ray flux variations on timescales of years as well as low amplitude variations on timescales as short as hours, while the X-ray spectral shape remained essentially unchanged. The spectrum shows a significant soft X-ray excess. The model of reflection from an ionized disc, that is dominant in the whole XMM-Newton bandpass, provides the best description of the observed spectra for all the observations, though alternatives such as Compton scattering ( T ∼ 0.25 keV) cannot be ruled out in a statistical sense. For the disc reflection model, the observed variations may originate either from the change in the reflection fraction, or from the variability of the intrinsic X-ray luminosity. [ABSTRACT FROM AUTHOR]

This study evaluated the correlation between DNA degradation of the splenic lymphocytes and the early time of death, examined the early time of death by computerized image analysis technique (CIAT) and identified the best parameter that quantitatively reflects the DNA degradation. The spleen tissues from 34 SD rats were collected, subjected to cell smearing every 2 h within the first 36 h after death, stained by Feulgen-Van’s staining, three indices reflecting DNA content in splenic lymphocytes, including integral optical density (IOD), average optical density (AOD), average gray scale (AG) were measured by the image analysis. Our results showed that IOD and AOD decreased and AG increased over time within the first 36 h. A stepwise linear regression analysis showed that only AG was fitted. A correlation between the postmortem interval (PMI) and AG was identified and the corresponding regression equation was obtained. Our study suggests that CIAT is a useful and promising tool for the estimation of early PMI with good objectivity and reproducibility, and AG is a more effective and better quantitative indicator for the estimation of PMI within the first 36 h after death in rats. [ABSTRACT FROM AUTHOR]

To investigate the potential malignant characteristics and pathogenesis of endometriosis as well as the role of human growth hormone and epidermal growth factor receptor in the pathogenesis of malignant transformation of endometriosis. The immunohistochemical S-P method was used to examine the expression of human growth hormone and epidermal growth factor receptor in the eutopic and ectopic endometrium of 84 cases of endometriosis. The percentage of positive cases of human growth hormone in eutopic and ectopic endometrium was 90.77% (59/65) and 85.71% (72/ 84) respectively. The percentage of positive cases of epidermal growth factor receptor in eutopic and ectopic endometrium was 81.54% (53/65) and 89.29% (75/84) respectively. The positive rate of epidermal growth factor receptor in ectopic endometrium was higher than that in the eutopic endometrium but without a statistically significant difference (P> 0.05). Endometriosis is caused by multiple factors, which possesses some biologic features of neoplastic tissue such as invasion and metastasis. Both human growth hormone and epidermal growth factor receptor are highly expressed in eutopic and ectopic endometrium, which lead directly or indirectly to the pathogenesis of endometriosis and promote the initiation and malignant transformation of endometriosis. [ABSTRACT FROM AUTHOR]

Glycosylation of hydrophobic peptides at one terminus effectively increases their water-solubility, and conjugation through the opposing end to a carrier protein, renders them more immunogenic. Moreover, the glycosylation minimizes antibody responses to potentially deleterious, non-productive terminal neo-epitope regions of the peptides, and consequently shifts peptide immunogenicity towards the core amino acid residues. As proof of concept, glycopeptide-protein conjugates related to influenza hemagglutinin (HA), neuraminidase (NA), and the dimerization loop region of human epidermal growth factor receptor 2 (Her2), demonstrated a favorable production of core peptide specific antibodies as determined by ELISA studies. Furthermore, glycosylated Her2 peptide conjugate antisera were also shown to recognize full length Her2 protein by ELISA and at the cell surface through flow cytometry analysis. In contrast, unmasked peptide conjugates generated significant antibody populations that were specific to the terminal neo-epitope of the peptide immunogen that are notably absent in parental proteins. Antibodies generated in this manner to peptides in the dimerization loop of Her2 are also functional as demonstrated by the growth inhibition of Her2 expressing SKBR3 carcinoma cells. This method provides a technique to tailor-make epitope-specific antibodies that may facilitate vaccine, therapeutic and diagnostic antibody development. [ABSTRACT FROM AUTHOR]

Ultra-low-loss and large-effective-area fiber has been successfully applied in transoceanic transmission, which is considered as a promising candidate for 100 Gbit/s and beyond 100 Gbit/s coherent long-haul terrestrial optical networks. Several theoretical and experimental investigations have been reported, including provincial terrestrial field trial. To support long-haul terrestrial application, it is urgent to prove that the ultra-low-loss and large-effective-area fiber after terrestrial deployment can significantly enhance the performance of long-haul transmission over 1000 km compared with the conventional single mode fiber. In this paper, we extended our previous work and summarized design methods for complex terrestrial environment. To verify the fiber characteristics in long-haul terrestrial transmission, we installed the longest terrestrial ultra-low-loss and large-effective-area fiber link in the world with a total length of 1539.6 km. The results show that the transmission performances of wavelength-division-multiplexed signals with per-channel data rates of 100 Gbit/s, 200 Gbit/s, and 400 Gbit/s over the ultra-low-loss and large-effective-area fiber are all obviously improved, demonstrating that this fiber is more suitable for ultrahigh-speed long-haul terrestrial transmission. [ABSTRACT FROM AUTHOR]

Gratings, one of the most important energy dispersive devices, are the fundamental building blocks for the majority of optical and optoelectronic systems. The grating period is the key parameter that limits the dispersion and resolution of the system. With the rapid development of large X-ray science facilities, gratings with periodicities below 50 nm are in urgent need for the development of ultrahigh-resolution X-ray spectroscopy. However, the wafer-scale fabrication of nanogratings through conventional patterning methods is difficult. Herein, we report a maskless and high-throughput method to generate wafer-scale, multilayer gratings with period in the sub-50 nm range. They are fabricated by a vacancy epitaxy process and coated with X-ray multilayers, which demonstrate extremely large angular dispersion at approximately 90 eV and 270 eV. The developed new method has great potential to produce ultrahigh line density multilayer gratings that can pave the way to cutting edge high-resolution spectroscopy and other X-ray applications. Fabrication of wafer-scale nanogratings for X-ray spectroscopy is difficult especially for very high line densities. The authors use vacancy epitaxy to fabricate sub-50-nm-periodicity gratings, coated with multilayers for efficient operation, for use in ultra-high resolution x-ray spectroscopy. [ABSTRACT FROM AUTHOR]