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Thermal expansion of the workpiece during cylinder boring process is one of the sources causing the bore cylindricity error. To study thermal expansion induced bore distortion, detailed workpiece temperature distribution in cylinder boring is required. Four finite element models, namely, the advection model, surface heat model, heat carrier model, and ring heat model, were developed to predict the workpiece temperature in cylinder boring. Cylinder boring experiments were conducted utilizing the tool-foil and embedded thermocouple experimental approaches to measure the workpiece temperature, predict the temperature distribution using the inverse heat transfer method, and evaluate the capability of the four models in terms of accuracy and efficiency. Results showed an accurate global temperature prediction for all models and a good correlation with the embedded thermocouple experimental measurements. Good correlation was also obtained between the tool-foil thermocouple measurement of machined surface temperature and model predictions. Advantages and disadvantages as well as applicable scenarios of each model were discussed. For studying detailed cylinder boring workpiece temperature, it is suggested to use the ring heat model to estimate the moving heat flux and the heat carrier model for local workpiece temperature calculation. [ABSTRACT FROM AUTHOR]

A simultaneous phase-shifting Twyman interferometer with a point source array is proposed. We use a point source in combination with a grating and select the four (±1, ±1) diffraction orders to generate a point source array. With this configuration, we can acquire four independent Twyman interferometers. Adjust the offset amounts of each point source to introduce different phase shifts in the interferograms, and realize dynamic measurement. We introduce 0, π∕2, π, and 3π∕2 in the interferograms. The initial phase will be exactly retrieved by employing the four-bucket algorithm. The experimental results show the feasibility and precision of the interferometer. [ABSTRACT FROM AUTHOR]

The clinical efficacy of microsurgical neck clipping for the treatment of cerebral aneurysm rupture and its effect on serum nuclear factor κ-light-chain-enhancer of activated ß cells (NF-κB), monocyte chemoattractant protein-1 (MCP-1) and matri-x metalloproteinase-9 (MMP-9)levels were investigated. A total of 56 patients with first occurrence of cerebral aneurysm rupture were enrolled from June 2015 to June 2016. These patients were divided into control (25 patients) and observation groups (31 patients) according to treatment received. The patients in the control group were treated with interventional embolization and extraventricular drainage, while the patients in the observation group were treated with microsurgical neck clipping. Serum NF-κB, MCP-1 and MMP-9 levels were measured by ELISA prior to the operation and at 6 h post-operation. Clinical effects were compared at the 6-month follow-up. There was no significant difference in the success rate of the operation between the two groups (p>0.05). The incidence of complications in the observation group was significantly lower than that in the control group (p<0.05). The Glasgow Outcome Scale score was significantly improved in the observation group (p<0.05) compared with the control group. Serum NF-κB, MMP-9 and MCP-1 were significantly decreased in both groups at 6 and 24 h after operation, but the observational group showed significantly lower levels for all three proteins than the control group (p<0.05). The application of early microsurgical neck clipping for the treatment of cerebral aneurysm rupture can reduce complications and improve clinical prognosis, and this may be related to a decrease in serum inflammatory response-related factors (NF-κB and MCP-1) and MMP-9. [ABSTRACT FROM AUTHOR]

Bone and dental diseases are serious public health problems. Most current clinical treatments for these diseases can produce side effects. Regeneration is a promising therapy for bone and dental diseases, yielding natural tissue recovery with few side effects. Because soft tissues inside the bone and dentin are densely populated with nerves and vessels, the study of bone and dentin regeneration should also consider the co-regeneration of nerves and vessels. In this study, a network-based method to identify co-regeneration genes for bone, dentin, nerve and vessel was constructed based on an extensive network of protein--protein interactions. Three procedures were applied in the network-based method. The first procedure, searching, sought the shortest paths connecting regeneration genes of one tissue type with regeneration genes of other tissues, thereby extracting possible co-regeneration genes. The second procedure, testing, employed a permutation test to evaluate whether possible genes were false discoveries; these genes were excluded by the testing procedure. The last procedure, screening, employed two rules, the betweenness ratio rule and interaction score rule, to select the most essential genes. A total of seventeen genes were inferred by the method, which were deemed to contribute to co-regeneration of at least two tissues. All these seventeen genes were extensively discussed to validate the utility of the method. [ABSTRACT FROM AUTHOR]

In order to understand the interfacial parameters governing the friction force (Ft) between silicon oxide surfaces in humid environment, the sliding speed (v) and relative humidity (RH) dependences of Ft were measured for a silica sphere (1 μm radius) sliding on a silicon oxide (SiOx) surface, using atomic force microscopy (AFM), and analyzed with a mathematical model describing interfacial contacts under a dynamic condition. Generally, Ft decreases logarithmically with increasing v to a cutoff value below which its dependence on interfacial chemistry and sliding condition is relatively weak. Above the cutoff value, the logarithmic v dependence could be divided into two regimes: (i) when RH is lower than 50%, Ft is a function of both v and RH; (ii) in contrast, at RH≥50%, Ft is a function of v only, but not RH. These complicated v and RH dependences were hypothesized to originate from the structure of the water layer adsorbed on the surface and the water meniscus around the annulus of the contact area. This hypothesis was tested by analyzing Ft as a function of the water meniscus area (Am) and volume (Vm) estimated from a thermally activated water-bridge formation model. Surprisingly, it was found that Ft varies linearly with Vm and correlates poorly with Am at RH < 50%; and then its Vm dependence becomes weaker as RH increases above 50%. Comparing the friction data with the attenuated total reflection infrared (ATR-IR) spectroscopy analysis result of the adsorbed water layer, it appeared that the solidlike water layer structure formed on the silica surface plays a critical role in friction at RH < 50% and its contribution diminishes at RH≥50%. These findings give a deeper insight into the role of water condensation in friction of the silicon oxide single asperity contact under ambient conditions. [ABSTRACT FROM AUTHOR]

Background: NLRP3 inflammasome acts as a danger signal sensor that triggers and coordinates the inflammatory response. However, the roles of NLRP3 inflammasome in the tumorigenesis and development of cancer stem cells (CSCs) of squamous cell carcinoma of the head and neck (SCCHN) remain ambiguous. Methods: In our study, tissue microarrays, ELISA, sphere-forming assay, colony formation assay and Western blot analysis were performed to evaluate the effect of NLRP3 inflammasome on the development of CSCs in human SCCHN tissue specimen, cell lines, and transgenic mouse SCCHN model. Results: The components of NLRP3 inflammasome, namely, NLRP3, ASC, Caspase-1, and IL-18 were correlated with CSCs markers BMI1, ALDH1 and CD44 in human SCCHN specimens. Moreover, NLRP3, Caspase-1, IL-1β, and IL-18 were highly expressed in SCCHN cell lines. NLRP3 inflammasome activated by LPS and ATP promoted sphere-forming and colony formation capacities along with an upregulation of BMI1, ALDH1 and CD44. In addition, NLRP3 inflammasome blockade by NLRP3 inhibitor MCC950 reduced sphere and colony number, also decreased the expression of BMI1, ALDH1 and CD44 in SCCHN cell lines. Expression of NLRP3, ASC, Caspase-1, IL-1β, IL-18, BMI1, ALDH1 and CD44 was upregulated in Tgfbr1/Pten 2cKO mouse SCCHN model, and NLRP3 inflammasome expression was closely related to those CSCs makers in mice SCCHN. However, MCC950 treatment reduced the expression of NLRP3 inflammasome, CSCs markers BMI1, ALDH1 and CD44 in Tgfbr1/Pten 2cKO mice SCCHN. In addition, blockade of NLRP3 inflammasome can also delayed the tumor-burdened speed in SCCHN mice. Conclusions: Our study demonstrates that NLRP3 inflammasome was upregulated and associated with the carcinogenesis and CSCs self-renewal activation in SCCHN. NLRP3 inflammasome can be a potential target in the development of novel approaches for head and neck squamous cell carcinoma therapy. [ABSTRACT FROM AUTHOR]

PALLD is an actin cross-linker supporting cellular mechanical tension. However, its involvement in the regulation of phagocytosis, a cellular activity essential for innate immunity and physiological tissue turnover, is unclear. We report that PALLD is highly induced along with all-trans-retinoic acid-induced maturation of myeloid leukemia cells, to promote Ig- or complement-opsonized phagocytosis. PALLD mechanistically facilitates phagocytic receptor clustering by regulating actin polymerization and c-Src dynamic activation during particle binding and early phagosome formation. PALLD is also required at the nascent phagosome to recruit phosphatase oculocerebrorenal syndrome of Lowe, which regulates phosphatidylinositol-4,5-bisphosphate hydrolysis and actin depolymerization to complete phagosome closure. Collectively, our results show a new function for PALLD as a crucial regulator of the early phase of phagocytosis by elaborating dynamic actin polymerization and depolymerization. [ABSTRACT FROM AUTHOR]

A soybean mutant displaying chicken toes-like leaves and petalody flowers was identified as being caused by a single recessive gene, termed ctp. Using heterozygous-inbred recombinants, this gene was fine-mapped to a 37-kb region harbouring three predicted genes on chromosome 5. The gene Glyma05g022400.1 was detected to have a 33-bp deletion in its first exon that was responsible for ctp. Validation for this gene was provided by the fact that the 33-bp deletion-derived marker I2 completely co-segregated with the phenotypes of 96 F10-derived residual heterozygous lines and 2200 fine-mapping individuals, and by the fact that the orthologue NbCTP in Nicotiana benthamiana also influenced leaf and flower development under virus-induced gene silencing. In terms of characterization, the CTPs shared highly conserved domains specifically in higher plants, GmCTP was alternatively spliced, and it was expressed in multiple organs, especially in lateral meristems. GmCTP was localized to the nucleus and other regions and performed transcriptional activity. In ctp, the expression levels and splicing patterns were dramatically disrupted, and many key regulators in leaf and/or floral developmental pathways were interrupted. Thus, CTP is a novel and critical pleiotropic regulator of leaf and flower development that participates in multiple regulation pathways, and may play key roles in lateral organ differentiation as a putative novel transcription regulator. [ABSTRACT FROM AUTHOR]

Clear and accurate understanding of diversity in antibody complementarity-determining regions (CDRs) is critical for antibody discovery and engineering. Previous observations of antibody CDR-H3 diversity were based on analyzing available antibody sequences in the public databases. The results may not accurately reflect that of natural antibody repertoire due to erroneous species annotation and the presence of man-made CDR loop diversity in public antibody sequence databases. In this study, in a precisely controlled germline context, we explored the relationship between amino acid composition and CDR-H3 length using 5518 unique productively rearranged human VH3-23*01 gene sequences. CDR-H3 length-dependent usage of the Cys-Xn-Cys motif is reported here. [ABSTRACT FROM AUTHOR]

Retinoic acid inducible gene I (RIG‑I) is upregulated during all‑trans retinoic acid (ATRA)‑induced terminal granulocytic differentiation of NB4 acute promyelocytic leukemia (APL) cells. However, the function and mechanism of RIG‑I in NB4 cells remains to be fully elucidated. In the present study, lentivirus‑mediated RIG‑I‑knockdown was used to investigate the proliferation, cell cycle and apoptotic processes of ATRA‑induced NB4 cells in vitro using an MTT assay and flow cytometry, respectively. The roles of RIG‑I and the AKT‑FOXO3A signaling pathway were investigated using western blot analysis. The results showed that the ATRA‑induced expression of RIG‑I was specifically and effectively knocked down at the mRNA and protein levels by lentivirus mediated RIG‑I short hairpin RNA. In addition, silencing of RIG‑I reduced the ATRA‑induced inhibition of NB4 cell proliferation, cell cycle arrest and apoptosis. Further investigations indicated that with ATRA‑induced expression of RIG‑I, levels of phosphorylated (p)AKT‑Thr308 and pForkhead Box (FOX) O3A‑Thr32 were decreased, the expression levels of cell cycle arrest protein p27 and the apoptotic protein, tumor necrosis factor‑related apoptosis‑inducing ligand (TRAIL), directly transcribed by FOXO3A were increased. By contrast, following the knockdown of ATRA‑induced expression of RIG‑I, the levels of pAKT‑Thr308 and pFOXO3A‑Thr32 were increased, and the protein expression levels of p27 and TRAIL were decreased. Taken together, these results showed that the knockdown of RIG‑I reduced the inhibition of cell proliferation, cell cycle arrest and apoptosis in the ATRA‑induced NB4 cells via the AKT‑FOXO3A signaling pathway. [ABSTRACT FROM AUTHOR]

Studies have implied that the circadian oscillation of mitogen-activated protein kinase (MAPK) signal pathways is crucial for hippocampus-dependent memory. NF1 mouse models (Nf1 heterozygous null mutants; Nf1+/-) displayed enhanced MAPK activity in the hippocampus and resulted in memory deficits. We assumed a link between MAPK pathways and hippocampal rhythmic oscillations, which have never been explored in Nf1+/- mice. We demonstrated that the level of extracellular signal-regulated kinases 1 and 2 (ERK1/2) phosphorylation in Nf1+/- mice were significantly higher at nighttime than at daytime. Moreover, the in vivo recording revealed that for the Nf1+/- group, the power spectral density of theta rhythm significantly decreased and the firing rates of pyramidal neurons increased. Our results indicated that the hippocampal MAPK oscillation and theta rhythmic oscillations in Nf1+/- mice were disturbed and hinted about a possible mechanism for the brain dysfunction in Nf1+/- mice. [ABSTRACT FROM AUTHOR]

In this work, we designed a process to assemble gold nanoparticles onto a three-dimensional (3D) polymer surface, which can then be monitored using surface-enhanced Raman scattering (SERS). This work is the first demonstration of the assembly of gold nanoparticles on a filter film and in situ measurement with Raman spectroscopy. Herein, a polyhexamethylene adipamide (Nylon66) film embedded in the organic filter film was used as a template to fabricate a tunable SERS-active substrate. A "hotspot"-rich gold-nanoparticle-decorated polymer substrate for SERS was prepared; this substrate exhibited high sensitivity in trace detection of targets. The study was conducted using 4-mercaptobenzoic acid as a probe molecule with the aim of comparing the scattering efficiency and the homogeneity of the Raman signal on selected substrates. In addition, we used the gold-decorated polymer film to detect a biotin-avidin complex. The most powerful advantage of the proposed microanalytical device is the in situ SERS application. The 3D nanoporous structures described in this work hold strong potential for use in various applications such as environmental monitoring and biomolecule detection. [ABSTRACT FROM AUTHOR]

Experimental research has been carried out on a single cylinder naturally aspirated spark ignition engine which was modified to operate with coal-bed gas fuel to investigate the method of improving operation stability and lean burn limit. Varied fuel composition with methane concentration 30-100% and CO2 volumetric fraction 0-0.7 was employed to simulate coal-bed methane (CBM) and coal mined methane (CMM), respectively. Hydrogen was then employed to improve operational stability and lean burn limit. The results show that a stable operation range of the engine was obtained under most of the fuel compositions even if up to CO2 volumetric fraction = 0.6 was employed. Besides lean burn limit, the unstable operation with COVTMEP > 10% only appears at lean burn limit as well as CO2 volumetric fraction = 0.7 at each equivalence ratio. The lean burn limit of coal-bed gas has been significantly enlarged from the equivalence ratio equals to 0.6-0.4 by hydrogen addition. Stable operation with COVIMEP < 5% at the equivalence ratio equals to 0.4 has also been obtained at some high hydrogen concentration conditions. Hydrogen addition induced the reduction of both carbon monoxide (CO) and total hydrocarbon (THC) emissions at all equivalence ratio conditions, especially at the equivalence ratio equals to 0.4 and 0.6. CO2 addition improves NOx emission significantly; however, high CO2 volumetric fraction will lead to unstable operation, which results in deteriorated CO and THC emissions. Hydrogen addition has benefits of improving operation stability and enlarging lean burn limit of coal-bed gas engine, which has practical significance to improve the application of coal-bed gas engine technology. [ABSTRACT FROM AUTHOR]

The blades are an important part of gas turbines and internal defects, such as cracks and holes, can occur in some gas turbine blades. Due to the harsh working environment, these defects have a great influence on the safe operation of the gas turbine in practical applications. In this paper, a new method based on a digital radiography (DR) system is adopted to detect defects in gas turbine blades. Considering the limited size of the fiat-panel detector in a DR system and the uneven thickness distribution of the irregular-shaped gas turbine blades, a region segmentation-based inspection method is presented in this paper. That is, the gas turbine blade is divided into a few regions using lead wires and the DR system is then used to inspect these sub-regions. Considering the high cost and low efficiency limitations of high-power computed tomography (Cf) and traditional film-based radiographic testing (RT), certain image processing methods are adopted to accurately automate the extraction and analysis processes. A cubic polynomial interpolation background subtraction method is adopted for the accurate extraction of defects. In addition, a finite element method is presented to obtain the 3D parameter (the volume) of a defect from its 2D radiographic image. Experimental results show that the proposed method can efficiently estimate the 2D and 3D geometric parameters of defects in gas turbine blades at a low cost. The method is particularly suitable for offline X-ray inspection of gas turbine blades. [ABSTRACT FROM AUTHOR]

The technology of energy piles for heat storage involves turning the concrete piles buried beneath the ground into a part of the ground-source heat pump system and burying the heat-transfer tubes in the foundation piles, which are regarded as heat transfer wells. The heat transfer tubes are embedded in the concrete foundation piles, destroying the mechanical bearing capacity of the piles and damaging the safety of the buildings. Thus, considering the structural stability and the degree of heat transfer of concrete piles, as well as the selection of material for the foundation piles, the mixing ratio of the material of the energy piles is experimentally studied by the orthogonal method. The optimum mixing ratio of the energy pile is thus obtained. A concrete test block is used to conduct a static load test and splitting test to verify the mixing ratio of the concrete of the energy pile. The results show that steel fiber can be used to enhance the bearing capacity of the storage pile as a reinforcement material. Under a reasonable ratio, the reinforced pile can absolutely meet the original design requirements. Ordinary Portland cement or composite Portland cement can be used as cementitious materials for energy piles. Through an experiment, it is proved that the composite Portland cement can better meet the requirements of the concrete foundation piles than the cementitious material. As thermal conductivity materials, the addition of industrial graphite and scrap copper slag can improve the thermal conductivity of the pile, but it can also reduce the mechanical properties of the pile. It is necessary to control it in a certain range and not to add a large amount of graphite just to improve the thermal conductivity. [ABSTRACT FROM AUTHOR]

Background: Reconstruction of large scalp defects after tumor resection is common and challenging. Free skin grafting or free flap transfer is always performed. However, these techniques can result in poor functional and cosmetic outcomes. Methods: In the Second Affiliated Hospital of Soochow University and the Second Affiliated Hospital of Chengdu Medical College, 35 patients underwent jigsaw puzzle flap procedures based on a free-style perforator to repair large scalp defects after tumor resection from May 2013 to November 2022. The key to this procedure was to divide a large defect into several smaller parts that correspond to adjacent free-style perforators around the scalp defect. The free-style perforator flaps were designed in different ways, such as propeller flaps, rotation flaps, and V-Y advancement flaps, which were pedicled with free-style perforators. All of the small flaps were then mobilized to the defect and sutured to each other to create a new, large jigsaw puzzle-like flap to cover the large scalp defect. Finally, all the donor sites were closed directly. Results: Overall, 35 patients were treated. The average defect size was 72 cm² (range, 25-91 cm²). All flaps had a satisfactory appearance after follow-up periods of 6 months--10 years. Local tumor recurrence occurred in one case. Conclusion: The application of a jigsaw puzzle flap based on a free-style perforator is a suitable option for the reconstruction of large scalp defects after resection, yielding satisfactory functional and cosmetic results. [ABSTRACT FROM AUTHOR]

While the structures of Brønsted acid sites (BAS) in zeolites are well understood, those of Lewis acid sites (LAS) remain an active area of investigation. Under hydrated conditions, the reversible formation of framework‐associated octahedral aluminum has been observed in zeolites in the acidic form. However, the structure and formation mechanisms are currently unknown. In this work, combined experimental 27Al NMR spectroscopy and computational data reveal for the first time the details of the zeolite framework‐associated octahedral aluminium. The octahedral LAS site becomes kinetically allowed and thermodynamically stable under wet conditions in the presence of multiple nearby BAS sites. The critical condition for the existence of such octahedral LAS appears to be the availability of three protons: at lower proton concentration, either by increasing the Si/Al or by ion‐exchange to non‐acidic form, the tetrahedral BAS becomes thermodynamically more stable. This work resolves the question about the nature and reversibility of framework‐associated octahedral aluminium in zeolites. [ABSTRACT FROM AUTHOR]

While the structures of Brønsted acid sites (BAS) in zeolites are well understood, those of Lewis acid sites (LAS) remain an active area of investigation. Under hydrated conditions, the reversible formation of framework‐associated octahedral aluminum has been observed in zeolites in the acidic form. However, the structure and formation mechanisms are currently unknown. In this work, combined experimental 27Al NMR spectroscopy and computational data reveal for the first time the details of the zeolite framework‐associated octahedral aluminium. The octahedral LAS site becomes kinetically allowed and thermodynamically stable under wet conditions in the presence of multiple nearby BAS sites. The critical condition for the existence of such octahedral LAS appears to be the availability of three protons: at lower proton concentration, either by increasing the Si/Al or by ion‐exchange to non‐acidic form, the tetrahedral BAS becomes thermodynamically more stable. This work resolves the question about the nature and reversibility of framework‐associated octahedral aluminium in zeolites. [ABSTRACT FROM AUTHOR]

Background: The phytopathogenic Xanthomonas campestris pv.campestris is a gram-negative bacterium and the causal agent of black-rot disease of cruciferous crops. Many gram-negative bacteria possess a family of proteins, called Dsbs, which are involved in disulfide bond formation in certain periplasmic proteins. In our preliminary screening of the virulence to the plants we identified that gene XC_0531 which annotated gene dsbD of Xanthomonas campestris pv. campestris (Xcc) is related to the virulence to the host plants. Results: Here, we found XC_0531 encoded a DsbD like protein. Its deletion is sensitive to DTT and copper, decreased accumulation of free thiols in periplasm. Its deletion also affected heme synthesis, position of Soret band and the production of peak c550. This suggests that XC_0531 is related to c-type cytochromes biogenesis. XC_0531 mutation decreased the utilization of different carbon sources (such as galactose, xylose, maltose, saccharose and glucose), reduced extracellular polysaccharide (EPS) production, decreased extracellular enzyme activities (protease, cellulose and amylase), slowed down growth rate of Xcc and weakened virulence to the plants. These results suggest that these phenotypes caused by XC_0531 mutation is possibly due to deficient biosynthesis of c-type cytochromes in respiration chain and the formation of disulfide bonds. Our work confirmed the function of XC_0531 and provide theory basis for scientists working on molecular mechanisms of cytochrome c biogenesis, pathogenesis of Xcc, development of EPS commercial values and protecting plant from black rot. Conclusion: We confirmed the function of gene XC_0531, which encodes a DsbD like protein, a protein correlated with c-type cytochrome biogenesis. This gene is related to the virulence to plants by affecting funtion of cytochromes c and probably disulfide bonds modification of proteins in type II secretion system (T2SS). [ABSTRACT FROM AUTHOR]

Over the last few decades, considerable research efforts have been directed toward the development of effective chemical syntheses of camptothecin and its analogs. The last comprehensive review of this area was published in 2003 and many effective new methods have since been reported for the stereoselective synthesis of the camptothecin alkaloids. In this account, we have summarized most of the novel synthetic approaches developed for the synthesis of camptothecins during the last decade. We have focused on strategies for the construction of the pentacyclic ring system and the different methods used to install the chiral quaternary center on the E ring of camptothecin. 1 Introduction 2 Synthesis of Racemic Camptothecins 3 Enantioselective Synthesis of Camptothecins 3.1 Sharpless Asymmetric Dihydroxylation 3.2 Catalytic Asymmetric Cyanosilylation 3.3 Auxiliary-Induced Asymmetric Carbonyl Addition 3.4 Catalytic Asymmetric Ethylation 3.5 Asymmetric Hydroxylation 4 Conclusion. [ABSTRACT FROM AUTHOR]

Event-based runoff–pollutant relationships have been the key for water quality management, but the scarcity of measured data results in poor model performance, especially for multiple rainfall events. In this study, a new framework was proposed for event-based non-point source (NPS) prediction and evaluation. The artificial neural network (ANN) was used to extend the runoff–pollutant relationship from complete data events to other data-scarce events. The interpolation method was then used to solve the problem of tail deviation in the simulated pollutographs. In addition, the entropy method was utilized to train the ANN for comprehensive evaluations. A case study was performed in the Three Gorges Reservoir Region, China. Results showed that the ANN performed well in the NPS simulation, especially for light rainfall events, and the phosphorus predictions were always more accurate than the nitrogen predictions under scarce data conditions. In addition, peak pollutant data scarcity had a significant impact on the model performance. Furthermore, these traditional indicators would lead to certain information loss during the model evaluation, but the entropy weighting method could provide a more accurate model evaluation. These results would be valuable for monitoring schemes and the quantitation of event-based NPS pollution, especially in data-poor catchments. [ABSTRACT FROM AUTHOR]

Controlled doping for adjustable material polarity and charge carrier concentration is the basis of semiconductor materials and devices, and it is much more difficult to achieve in ionic semiconductors (e.g., ZnO and GaN) than in covalent semiconductors (e.g., Si and Ge), due to the high intrinsic defect density in ionic semiconductors. The organic-inorganic perovskite material, which is frenetically being researched for applications in solar cells and beyond, is also an ionic semiconductor. Here we present the Ag-incorporated organic-inorganic perovskite films and planar heterojunction solar cells. Partial substitution of Pb2+ by Ag+ leads to improved film morphology, crystallinity, and carrier dynamics as well as shifted Fermi level and reduced electron concentration. Consequently, in planar heterojunction photovoltaic devices with inverted stacking structure, Ag incorporation results in an enhancement of the power conversion efficiency from 16.0% to 18.4% in MAPbI3 based devices and from 11.2% to 15.4% in MAPbI3-x Cl x based devices. Our work implies that Ag incorporation is a feasible route to adjust carrier concentrations in solution-processed perovskite materials in spite of the high concentration of intrinsic defects. [ABSTRACT FROM AUTHOR]

We investigate the anisotropic magnetoelectric(ME) characteristics for the five-layer magnetization-graded multiferroic composites(MGMC). The magnetic anisotropy and corresponding anisotropic magnetomechanical effect, demagnetization effect and magneto-mechanical damping's dependence on magnetic field direction result in an obvious anisotropic ME coupling effect. The experimental results show that ME voltage coefficient in H33 mode is remarkably larger than the other ones (H11, H31 and H13) over the whole Hdc range. Correspondingly, ∂VME/∂Hdc arrives about 420mV/Oe at an optimum bias magnetic field of 46Oe, which is approximately 40 times larger than that of the previous reported composite. Furthermore, it also demonstrates an obvious angular dependence on dc magnetic field. Taking advantage of these specifications, the MGMC can be used to detect weak dc magnetic field and its spatial orientation. [ABSTRACT FROM AUTHOR]

LncRNA-LET, a recently identified long noncoding RNA, has been shown to act as a tumor suppressor; however, its biological function and mechanism have not been fully investigated. Our research found that there was less expression of LET in nasopharyngeal carcinoma (NPC) tissues than normal tissues and that LET might inhibit proliferation, adhesion and invasion of NPC in vitro by enhancing its expression. By contrast, decreased LET expression could promote the proliferation, adhesion and invasion of NPC. In addition, the expression profiles of related genes and MAPK/ERK pathway were also regulated effectively via overexpression or silencing of LET. This result provides comprehensive evidence of LET's antitumor effect on NPC in vitro, which might provide a new approach for clinical treatment. [ABSTRACT FROM AUTHOR]

Comprehending user demands through several human-computer interactions can effectively increase information-retrieval accuracy. Mainstream active learning algorithms use uncertainty sampling strategy. However, such algorithms cannot produce satisfactory results under few interactions. To improve interactive information-retrieval efficiency and accuracy, an sampling strategy based on the error-correcting capacity of samples was proposed for active learning. This strategy evaluated the expected value of unlabeled samples by calculating their potential error-correcting capacity associated with the classifier. Based on this sampling strategy, a fast interactive information-retrieval scheme adopting reinforcement learning and low-complexity classifier was designed in this study. The effects of three sampling strategies (random sampling, uncertainty sampling, and the proposed sampling strategy based on error-correcting capacity) on information-retrieval accuracy were examined using an experiment through a text set of Reuters-21578. Experimental results demonstrated that the proposed sampling strategy achieved higher retrieval accuracy and stability than random and uncertainty samplings. The retrieval accuracy of the proposed scheme was approximately 1.6% higher than that of the sampling algorithm based on uncertainty strategy. The proposed scheme can be used for real-time information retrieval because of its low computational complexity. The production of this study can improve the accuracy and latency of interactive information-retrieval services. [ABSTRACT FROM AUTHOR]

Background: Cisplatin-based chemotherapy is frequently used to treat advanced gastric cancer (GC). However, the resistance often occurs with the mechanisms being not well understood. Recently, emerging evidence indicates that tumor-associated macrophages (TAMs) play an important role in chemoresistance of cancer. As the important mediators in intercellular communications, exosomes secreted by host cells mediate the exchange of genetic materials and proteins to be involved in tumor aggressiveness. The aim of the study was to investigate whether exosomes derived from TAMs mediate cisplatin resistance in gastric cancer. Methods: M2 polarized macrophages were obtained from mouse bone marrow or human PBMCs stimulated with IL-4 and IL-13. Exosomes isolated from M2 macrophages culture medium were characterized, and miRNA expression profiles of M2 derived exosomes (M2-exos) were analyzed using miRNA microarray. In vitro cell coculture was further conducted to investigate M2-exos mediated crosstalk between TAMs and tumor cells. Moreover, the in vivo experiments were performed using a subcutaneous transplantation tumor model in athymic nude mice. Results: In this study, we showed that M2 polarized macrophages promoted cisplatin (DDP) resistance in gastric cancer cells and exosomes derived from M2 macrophages (M2-exos) are involved in mediating the resistance to DDP. Using miRNA profiles assay, we identify significantly higher levels of microRNA-21 (miR21) isomiRNAs in exosomes and cell lysate isolated from M2 polarized macrophage. Functional studies revealed that exosomal miR-21 can be directly transferred from macrophages to the gastric cancer cells, where it suppresses cell apoptosis and enhances activation of PI3K/AKT signaling pathway by down-regulation of PTEN. Conclusions: Our findings suggest that exosomal transfer of tumor-associated macrophages derived miR-21 confer DDP resistance in gastric cancer, and targeting exosome communication may be a promising new therapeutic strategy for gastric cancer patients. [ABSTRACT FROM AUTHOR]

Chitinase-h (Chi-h) is of special interest among insect chitinases due to its exclusive distribution in lepidopteran insects and high sequence identity with bacterial and baculovirus homologs. Here OfChi-h, a Chi-h from Ostrinia furnacalis, was investigated. Crystal structures of both OfChi-h and its complex with chitoheptaose ((GlcN)7) reveal that OfChi-h possesses a long and asymmetric substrate binding cleft, which is a typical characteristics of a processive exo-chitinase. The structural comparison between OfChi-h and its bacterial homolog SmChiA uncovered two phenylalanine-to-tryptophan site variants in OfChi-h at subsites +2 and possibly -7. The F232W/F396W double mutant endowedSmChiA with higher hydrolytic activities toward insoluble substrates, such as insect cuticle, α-chitin, and chitin nanowhisker. An enzymatic assay demonstrated that OfChi-h outperformed OfChtI, an insect endochitinase, toward the insoluble substrates, but showed lower activity toward the soluble substrate ethylene glycol chitin. Furthermore, OfChi-h was found to be inhibited by N,N′,N″-trimethylglucosamine-N,N′,N″,N″′-tetraacetylchitotetraose (TMG-(GlcNAc)4), a substrate analog which can be degraded into TMG-(GlcNAc)1-2. Injection of TMG-(GlcNAc)4 into 5th-instar O. furnacalis larvae led to severe defects in pupation. This work provides insights into a molting-indispensable insect chitinase that is phylogenetically closer to bacterial chitinases than insect chitinases. [ABSTRACT FROM AUTHOR]

Background Optimal management of complicated chronic type B dissection with involvement of the distal aortic arch is controversial. Late complications related to thoracic endovascular aortic repair (TEVAR) are much more common than those using open aortic surgery. We reviewed our experience of left subclavian artery (LSCA) transposition with implantation of a stented elephant trunk for complicated chronic type B dissection with involvement of the distal aortic arch. Materials and Methods From January 2011 to June 2015, 20 patients with complicated chronic type B dissection with involvement of the distal aortic arch underwent LSCA transposition with implantation of a stented elephant trunk via a median sternotomy under hypothermic cardiopulmonary bypass with selective antegrade cerebral perfusion (SACP). Preoperative renal dysfunction was observed in three patients, left heart failure in one patient, and spinal cord ischemia in one patient. Results There was one (5.0%, 1/20) in-hospital death. All but one patient required mechanical ventilation for < 24 hours. Mean duration of mechanical ventilation and mean duration of stay in the intensive care unit was 16 ± 4 and 35 ± 16 hours, respectively. No severe complications occurred. There was one death because of unknown cause during follow-up. One case received thoracoabdominal aortic replacement 9 months after surgery. Conclusion Acceptable surgical outcomes were obtained using LSCA transposition with implantation of a stented elephant trunk. This method is an alternative to TEVAR for complicated chronic type B dissection with involvement of the distal aortic arch. [ABSTRACT FROM AUTHOR]

Background: The study was designed to investigate the roles of endometrial thickness (EMT) at the day of human chorionic gonadotropin (hCG) administration on pregnancy outcomes in a large patient population. Methods: This retrospective cohort study included 9,952 patients undergoing their first IVF/ICSI with autologous oocytes from January 2011 to January 2015. Patients were divided into three groups based on the EMT (group A:≤8 mm; group B: 9-14 mm and group C:≥15 mm). Live birth rate (LBR), clinical pregnancy rate (CPR), early miscarriage rate (EMR), and ectopic pregnancy rate (EPR) were analyzed. Additionally, the live birth rate was analyzed for patients with single or double gestational sacs. Results: Significant differences (p < 0.05) were detected in the LBRs (30.38%, 45.73% and 54.55% for groups A, B, and C, respectively), CPRs (38.57%, 55.04% and 64.32%, respectively), and EPRs (5.58%, 3.48% and 2.19%, respectively), with thicker endometrial thickness favoring all three parameters. However, no differences were found in the EMRs among the three groups (15.64%, 13.44% and 13.05%, respectively, p > 0.05). After adjusting for female age, body mass index (BMI) and endometrial pattern, the multivariate logistic regression analysis demonstrated that the associations between EMT and LBR (adjusted OR: 2.645; 95% CI 2.020-3.464; p < 0.01), CPR (adjusted OR 2.693 95% CI 2.012-3.605 p < 0.01), and EPR (adjusted OR: 0.298 95% CI 0.101-0.713; p < 0.05) were significant. Additionally, live birth rates in the double gestational sac group were different (p < 0.05) among patients with different EMT (72.73%, 87.28%, and 87.36%, respectively), whereas no difference was found in the single gestational sac group. In the double gestational sac group, LBR was positively correlated with increasing endometrial thickness only in patients with twin pregnancies but not in patients with singletons. Conclusions: Our study shows that endometrial thickness at the day of hCG administration has an effect on LBR, CPR and EPR, with all three parameters increasing with the EMT. Furthermore, successful twin pregnancies are associated with a thicker endometrium. [ABSTRACT FROM AUTHOR]

In regard to the rapid development of renewable energy sources, more and more photovoltaic (PV) generation systems have been connected to main power networks, and it is critical to enhance their transient performance under short-circuit faults conditions. This paper proposes and studies the coordinated control of a flux-coupling-type superconducting fault current limiter (SFCL) and a superconducting magnetic energy storage (SMES), to improve the fault ride through (FRT) capability and smooth the power fluctuation of a grid-connected PV generation system. Theoretical analyses of the device structure, operating principle and control strategy are conducted, and a detailed simulation model of 100 kW class PV generation system is built in MATLAB/SIMULINK. During the simulations of the symmetrical and asymmetrical faults, the maximum power point tracking (MPPT) control is disabled, and four different cases including without auxiliary, with SFCL, with SMES, and with SFCL-SMES, are compared. From the demonstrated results, the combination of without MPPT and with SFCL-SMES can more efficiently improve the point of common coupling (PCC) voltage sag, inhibit the DC-link overvoltage and alleviate the power fluctuation. Finally, a preliminary parameter optimization method is suggested for the SFCL and the SMES, and it is helpful to promote their future application in the real PV projects. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the efficacy of tangeretin, a bioactive flavonoid, as an enhancer of tumour necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis in human lung cancer cells (H1299 and H1975). Methods: H1299 and H1975 cells were exposed to tangeretin (25, 50, or 100 µM), and its effect on cell viability was assessed by MTT assay. The cytotoxic effects of tangeretin in combination with TRAIL (25 ng/mL) were determined by live/dead assay and annexin V staining. Intracellular levels of reactive oxygen species (ROS) were determined by DHFDA-flow cytometry analysis. Western blotting was performed to assess the expression of death receptors, apoptosis pathway proteins, JNK and ERK1/2. The cell surface expression of death receptors was determined. RT-PCR was performed to assess the expression of death receptor 5 and CEBP homologous protein (CHOP) mRNA. The cytotoxic effects of tangeretin in the presence of DR5, CHOP siRNA and TRAIL were also detected. Results: MTT assay revealed that tangeretin exerted potent cytotoxic effects and, in combination with TRAIL, exhibited striking apoptosis. Down-regulation of cell survival proteins (Bcl-2, Bcl-xL, survivin, xIAP, c-IAP-1, and c-IAP-2) and elevated expression of Bax and caspases 3, 8, and 9 were observed upon tangeretin exposure. The expression of death receptors DR4 and DR5 was highly up-regulated by tangeretin, while that of decoy receptors DcR1 and DcR2 was down-regulated. DR5 and CHOP siRNA transfection suggested the involvement of CHOP in tangeretin-mediated up-regulation of DR5, leading to more pronounced apoptotic effects. Tangeretin increased ROS levels and effectively caused activation of the mitogen-activated protein kinases JNK, ERK, and p38MAPKs. Expression analysis in the presence of specific MAPK inhibitors suggested the involvement of JNK and ERK in tangeretinmediated TRAIL sensitisation. Conclusions: Tangeretin induces death receptors and enhances TRAIL-induced apoptosis through upregulation of the ROS-JNK/ERK-CHOP pathways. [ABSTRACT FROM AUTHOR]

For the problem of low accuracy, time-consuming and quantified faults cannot be provided that the current methods have, a fault recognition method based on affinity propagation clustering algorithm and least square curve fitting is proposed. Firstly, discontinuous points of horizons were located by the connected component labeling method and used as control points of the faults. Then, the discontinuous points were clustered by the affinity propagation clustering algorithm and the points of the same cluster were used to determine a fault. The number of the faults was determined by the number of classes after clustering. At the end, the discontinuous points of the same cluster were fitted by the least square curve fitting, and the curves were the desired faults. By the proposed method, the time consuming cross correlation calculation of the traditional method was discarded, the computing process was simplified and the faults were quantified. To validate the effectiveness, the proposed algorithm was compared with the traditional and the latest methods on the real seismic data and the experimental results confirmed that the accuracy of the proposed algorithm is better and the time consumption is reduced greatly. [ABSTRACT FROM AUTHOR]

A superconducting quantum interference device (SQUID) miniaturized into the nanoscale is promising in the inductive detection of a single electron spin. A nano-SQUID with a strong spin coupling coefficient, a low flux noise, and a wide working magnetic field range is highly desired in a single spin resonance measurement. Nano-SQUIDs with Dayem bridge junctions excel in a high working field range and in the direct coupling from spins to the bridge. However, the common planar structure of nano-SQUIDs is known for problems such as a shallow flux modulation depth and a troublesome hysteresis in current-voltage curves. Here, we developed a fabrication process for creating three-dimensional (3-D) niobium (Nb) nano-SQUIDs with nanobridge junctions that can be tuned independently. Characterization of the device shows up to 45.9% modulation depth with a reversible current-voltage curve. Owning to the large modulation depth, the measured flux noise is as low as 0.34 μφ0/Hz1/2. The working field range of the SQUID is greater than 0.5 T parallel to the SQUID plane. We believe that 3-D Nb nano-SQUIDs provide a promising step toward effective single-spin inductive detection. [ABSTRACT FROM AUTHOR]

Optical inhomogeneity is an important index to evaluate optical transmission material. We propose an absolute measurement method for optical inhomogeneity of the parallel plate with phase-shifting interferometry (PSI). Compared with the window-flipping method, we introduce another transmission flat and add two cavity measurements between the two transmission flats and the reflective flat with the assistance of a Fizeau interferometer. Simulation and experiment results show that the method can effectively eliminate the disturbances of both surfaces of the parallel plate, the reflective flat, and the system error of the interferometer. It reduces the requirement for surface accuracy of the transmission and reflective flats. It is an absolute measurement method for the optical inhomogeneity of the parallel plate, which can be realized with traditional phase-shifting interferometry. [ABSTRACT FROM AUTHOR]

Following disasters, emergency management agencies are under immense pressure to make quick decisions regarding the provision of temporary housing, including their locations and types. Such decisions can significantly impact the socioeconomic recovery of displaced families and available budgets for other postdisaster activities. To address these challenges, a new holistic temporary housing planning framework is proposed to offer customized housing plans tailored to the specific social, economic, and psychological needs of displaced families while controlling expenditures. This paper presents the theoretical formulation and implementation details of the community-based housing response pool, which is a comprehensive framework that aims at (1) quantifying the specific needs and preferences of each displaced family, (2) evaluating the ability of housing alternatives to meet those needs, (3) computing temporary housing life cycle costs, and (4) optimizing housing decisions accordingly. The paper also presents an application example to demonstrate and evaluate the optimization model capabilities. [ABSTRACT FROM AUTHOR]

A sensitive and selective fluorescence "turn-off" sensor to detect heparin using water-soluble silicon nanoparticles (Si NPs) was developed for the first time. The Si NPs were synthesized by a simple one-step procedure, which did not need high-temperature and complex modification. The asprepared Si NPs featured strong fluorescence, favorable biocompatibility, and robust photo- and pH stability. Significantly, the Si NPs were induced to assemble or aggregate via hydrogen bonding, which resulted in the fluorescence of Si NPs quenched. Under the optimized conditions, the linear range was obtained from 0.02 to 2.0 μg/mL, with a limit of detection of 18 ng/mL (equal to 0.004 U/mL). It was lower than the proper therapeutic level of heparin during cardiovascular surgery and long-term therapy. This proposed method was relatively free of interference from heparin analogues, which commonly existed in heparin samples and could possibly affect heparin detection. Moreover, it did not need to introduce any control medium. As expected, the method was successfully applied to detect heparin in human serum samples with satisfactory recovery ranging from 98.8 to 102.5%. The Si NPs were superbly suitable for cell imaging owing to the negligible cytotoxicity and excellent biocompatibility. [ABSTRACT FROM AUTHOR]

Background: Gliomas are the most common type of primary brain tumour in the central nervous system of adults. The long non-coding RNA (lncRNA) HOXA transcript at the distal tip (HOTTIP) is transcribed from the 5' tip of the HOXA locus. HOTTIP has recently been shown to be dysregulated and play an important role in the progression of several cancers. However, little is known about whether and how HOTTIP regulates glioma development. Methods: In this study, we assayed the expression of HOTTIP in glioma tissue samples and glioma cell lines using real-time polymerase chain reaction and defined the biological functions of HOTTIP using the CCK-8 assay, flow cytometry, terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL assay) and tumour formation assay in a nude mouse model. Finally, we discovered the underlying mechanism using the Apoptosis PCR 384HT Array, Western blot, RNA immunoprecipitation (RIP) and luciferase reporter assay. Results: HOTTIP was aberrantly down-regulated in glioma tissues and glioma cell lines (U87-MG, U118-MG, U251 and A172), and over-expression of HOTTIP inhibited the growth of glioma cell lines in vitro and in vivo. Furthermore, HOTTIP could directly bind to the brain and reproductive expression (BRE) gene and down-regulate BRE gene expression. In addition, we further verified that over-expression of the BRE gene promoted the growth of glioma cell lines in vitro. Finally, over-expression of HOTTIP significantly suppressed the expression of the cyclin A and CDK2 proteins and increased the expression of the P53 protein. However, we found that the over-expression of BRE significantly increased the expression of the cyclin A and CDK2 proteins and suppressed the expression of the P53 protein. Taken together, these findings suggested that high levels of HOTTIP reduced glioma cell growth. Additionally, the mechanism of HOTTIP-mediated reduction of glioma cell growth may involve the suppression of cyclin A and CDK2 protein expression, which increases P53 protein expression via the down-regulation of BRE. Conclusions: Our studies demonstrated that over-expression of HOTTIP promotes cell apoptosis and inhibits cell growth in U118-MG and U87-MG human glioma cell lines by down-regulating BRE expression to regulate the expression of P53, CDK2 and Cyclin A proteins. The data described in this study indicate that HOTTIP is an interesting candidate for further functional studies in glioma and demonstrate the potential application of HOTTIP in glioma therapy. [ABSTRACT FROM AUTHOR]

Background: 3-hydroxypropionic acid (3-HP) is an important platform chemical with a wide range of applications. In our previous study, the biosynthetic pathway of 3-HP was constructed and optimized in cyanobacterium Synechocystis sp. PCC 6803, which led to 3-HP production directly from CO2 at a level of 837.18 mg L-1 (348.8 mg/g dry cell weight). As the production and accumulation of 3-HP in cells affect cellular metabolism, a better understanding of cellular responses to 3-HP synthesized internally in Synechocystis will be important for further increasing 3-HP productivity in cyanobacterial chassis. Results: Using a engineered 3-HP-producing SM strain, in this study, the cellular responses to 3-HP internally produced were first determined using a quantitative iTRAQ-LC-MS/MS proteomics approach and a LC-MS-based targeted metabolomics. A total of 2264 unique proteins were identified, which represented about 63 % of all predicted protein in Synechocystis in the proteomic analysis; meanwhile intracellular abundance of 24 key metabolites was determined by a comparative metabolomic analysis of the 3-HP-producing strain SM and wild type. Among all identified proteins, 204 proteins were found up-regulated and 123 proteins were found down-regulated, respectively. The proteins related to oxidative phosphorylation, photosynthesis, ribosome, central carbon metabolism, two-component systems and ABC-type transporters were up-regulated, along with the abundance of 14 metabolites related to central metabolism. The results suggested that the supply of ATP and NADPH was increased significantly, and the precursor malonyl-CoA and acetyl-CoA may also be supplemented when 3-HP was produced at a high level in Synechocystis. Confirmation of proteomic and metabolomic results with RT-qPCR and gene-overexpression strains of selected genes was also conducted, and the overexpression of three transporter genes putatively involved in cobalt/nickel, manganese and phosphate transporting (i.e., sll0385, sll1598 and sll0679) could lead to an increased 3-HP production in Synechocystis. Conclusions: The integrative analysis of up-regulated proteome and metabolome data showed that to ensure the high-efficient production of 3-HP and the normal growth of Synechocystis, multiple aspects of cells metabolism including energy, reducing power supply, central carbon metabolism, the stress responses and protein synthesis were enhanced in Synechocystis. The study provides an important basis for further engineering cyanobacteria for high 3-HP production. [ABSTRACT FROM AUTHOR]

The effect of Nb addition on the magnetic properties, microstructure, and site preference has been investigated in single-phase Nd. 0.94 T, H = 919.0 kA/m, and (BH) = 143.1 kJ/m were achieved by annealing the melt-spun ribbons with x = 1.5 at 650 C for 10 min. Additions of Nb were effective in refining the grain size and improving the magnetic properties. Transmission electron microscopy (TEM) showed that there was no second phase or precipitate found in grain boundaries. The results of three-dimensional atom probe (3DAP) indicated that Nb may enter into the amorphous structure and NdFeB. The content of Nb in NdFeB was very small. Theoretical calculation showed that Nb preferentially substituted Fe atoms at the 8j sites and the volume of a cell would slightly enlarge. [ABSTRACT FROM AUTHOR]

Angiographically occult cerebrovascular malformation (AOVM) is a type of complex cerebrovascular malformation that is not visible on digital subtraction angiography (DSA). Vascular malformation coexisting with glioma is clinically rare, and glioma coexisting with AOVM is even more rare. To the best of our knowledge, the present study is the first to report glioma coexisting with AOVM in the literature. The present study reports a rare case of glioma coexisting with AOVM in a 30-year-old male patient. Computed tomography (CT) scan revealed calcification, hemorrhage and edema in the right frontal lobe. CT angiography revealed a vascular malformation in the right frontal lobe, which was not observed on DSA. Finally, glioma coexisting with AOVM was confirmed by 2.0T magnetic resonance imaging and postoperative pathological examination. The present patient had a positive outcome and no neurological dysfunctions during the 6-month follow-up subsequent to surgery. [ABSTRACT FROM AUTHOR]

Concerning the development of a micro-grid integrated with multiple intermittent renewable energy resources, one of the main issues is related to the improvement of its robustness against short-circuit faults. In a sense, the superconducting fault current limiter (SFCL) can be regarded as a feasible approach to enhance the transient performance of a micro-grid under fault conditions. In this paper, the fault transient analysis of a micro-grid, including distributed generation, energy storage and power loads, is conducted, and regarding the application of one or more flux-coupling-type SFCLs in the micro-grid, an integrated technical evaluation method considering current-limiting performance, bus voltage stability and device cost is proposed. In order to assess the performance of the SFCLs and verify the effectiveness of the evaluation method, different fault cases of a 10-kV micro-grid with photovoltaic (PV), wind generator and energy storage are simulated in the MATLAB software. The results show that, the efficient use of the SFCLs for the micro-grid can contribute to reducing the fault current, improving the voltage sags and suppressing the frequency fluctuations. Moreover, there will be a compromise design to fully take advantage of the SFCL parameters, and thus, the transient performance of the micro-grid can be guaranteed. [ABSTRACT FROM AUTHOR]

Objectives: Harris Health System (HHS) is a safety net system providing health care to the underserved of Harris County, Texas. There was a 6-month waiting period for a rheumatologist consult for patients with suspected systemic lupus erythematosus (SLE). The objective of the intervention was to improve access to specialty care. Methods: An algorithmic approach to testing for SLE was implemented initially through the HHS referral center. The algorithm was further offered as a "one-click" order for physicians, with automated reflex testing, interpretation, and case triaging by clinical pathology. Results: Data review revealed that prior to the intervention, 80% of patients did not have complete laboratory workups available at the first rheumatology visit. Implementation of algorithmic testing and triaging of referrals by pathologists resulted in decreasing the waiting time for a rheumatologist by 50%. Conclusions: Clinical pathology intervention and case triaging can improve access to care in a county health care system. [ABSTRACT FROM AUTHOR]

Since Jeff Howe introduced the term Crowdsourcing in 2006, this human-powered problem-solving paradigm has gained a lot of attention and has been a hot research topic in the field of computer science. Even though a lot of work has been conducted on this topic, so far we do not have a comprehensive survey on most relevant work done in the crowdsourcing field. In this paper, we aim to offer an overall picture of the current state of the art techniques in general-purpose crowdsourcing. According to their focus, we divide this work into three parts, which are: incentive design, task assignment, and quality control. For each part, we start with different problems faced in that area followed by a brief description of existing work and a discussion of pros and cons. In addition, we also present a real scenario on how the different techniques are used in implementing a location-based crowdsourcing platform, gMission. Finally, we highlight the limitations of the current general-purpose crowdsourcing techniques and present some open problems in this area. [ABSTRACT FROM PUBLISHER]

It is a great challenge to maintain thermally stable luminescence of red phosphors in white light-emitting diodes (LEDs), because of the large Stokes shift. For the purpose of overcoming this challenge, this work elucidates the intrinsic mechanism of the thermal quenching luminescence of CaAlSiN3:Eu2+. The empty 5d orbital of Eu2+ is partly filled with electrons upon Eu2+ increasing, as observed using XANES; and the exceptional expansion of the local Eu-N bond length, the ratio of which is far larger than the volume expansion of crystal lattice brought by doping Eu2+, is measured using EXAFS. The shift of Fermi level predicted with the first-principles calculations is confirmed by the valence band spectra. Therefore, the changeable distribution of electrons on the excited substates and then thermal delocalization to the conduction band are the intrinsic mechanisms of thermal quenching luminescence of CaAlSiN3:Eu2+. The results provide a solid basis for exploring the methods to enhance the thermal stable luminescence of CaAlSiN3:Eu2+. [ABSTRACT FROM AUTHOR]

Background: Type 2 trigeminal neuralgia (TN) is an intractable neuropathic pain syndrome compared with type 1 TN because of the difficulty of diagnosis as well as the unsatisfactory prognosis. Neurovascular compression (NVC) is considered the major pathology of TN. Routine magnetic resonance imaging (MRI) sequences are inadequate for revealing the effect of NVC which is related to the surgical decision and outcome. The decreasing of fractional anisotropy (FA), one of the MRI diffusion tensor imaging (DTI) metrics, is correlated with the demyelination of trigeminal nerve (TGN) that reveal the severity of NVC.Methods: A retrospective review of patients treated with micro-vascular decompression (MVD) surgery was undertaken. All the patients were diagnosed as type 2 TN. FA of TGN of both sides were measured. The FA declining proportion = ((the mean FA value of healthy lateral)-(the mean FA value of the symptomatic lateral))/(the mean FA value of healthy lateral). Declining proportion of FA value, discovery of surgery and outcome of MVD were recorded and analyzed. Logistic regression analysis and linear regression analysis were employed to analyze the risk factors of declining proportion of FA value and MVD outcome.Results: Nineteen patients were assessed in our study. The average declining proportion of FA value for all patients was 0.25 ± 0.12. The average declining proportion of FA value of "success" and "failure" group was 0.32 ± 0.09 to 0.14 ± 0.10 (P = 0.002 < 0.05). The declining proportion of FA value of artery (including the artery plus vein situation) was 0.34 ± 0.06 in contrast to 0.15 ± 0.08 of vein (P = 0.000 < 0.05). MVD outcome was correlated with declining proportion of FA value (AUC = 0.900). Furthermore, declining proportion of FA value was higher in arterial compression situation.Conclusion: FA value quantitatively showed the alteration of TGN caused by NVC. It provided direct evidence about the effect of NVC which facilitated the diagnosis and surgical decision of type 2 TN. Besides, significant reduction of FA value may predict an optimistic outcome of MVD. [ABSTRACT FROM AUTHOR]

Couette flow has been widely used in many industrial and research processes, such as viscosity measurement. For the study on thixotropic viscosity, step-loading, which includes (1) step shear stress and (2) step velocity conditions, is widely used. Transient stages of Couette flow under both step wall shear stress and step wall velocity conditions were investigated. The relative coefficient of viscosity was proposed to reflect the transient process. Relative coefficients of viscosity, dimensionless velocities and dimensionless development times were derived and calculated numerically. This article quantifies the relative coefficients of viscosity as functions of dimensionless time and step ratios when the boundary is subjected to step changes. As expected, in the absence of step changes, the expressions reduce to being functions of dimensionless time. When step wall shear stresses are imposed, the relative coefficients of viscosity change from the values of the step ratios to their steady-state value of 1. But with step-increasing wall velocities, the relative coefficients of viscosity decrease from positive infinity to 1. The relative coefficients of viscosity increase from negative infinity to 1 under the step-decreasing wall velocity condition. During the very initial stage, the relative coefficients of viscosity under step wall velocity conditions are further from 1 than the one under step wall shear stress conditions but the former reaches 1 faster. Dimensionless development times grow with the step ratio under the step-rising conditions and approach the constant value of 1.785 under the step wall shear stress condition, and 0.537 under the step wall velocity condition respectively. The development times under the imposed step wall shear stress conditions are always larger than the same under the imposed step wall velocity conditions. [ABSTRACT FROM AUTHOR]

A novel converter that can directly transform electrical, wind, hydraulic and other types of mechanical energy into thermal energy is presented in this study. First, the thermal energy of the converter is classified and then calculated by a finite element method. The eddy current distribution in the stator of the converter is also discussed. Second, the temperature field of the converter is calculated using a boundary element method. Subsequently, a thermal power-temperature coupled calculation method is presented to calculate the actual thermal power and temperature of the converter. The characteristic curves of the actual thermal power and the increase in water flow temperature are then presented based on the calculation results. Lastly, an experimental system is built, the thermal power and temperature of the converter are measured and the experimental results and the analytical calculations are compared. [ABSTRACT FROM AUTHOR]

[Display omitted] • N-doped CDs obtained facilely by just reflux heating on CDs and m -phenylenediamine. • N-doping realized red-shift emission and enhancement of fluorescent quantum yield. • Fluorophore of both CDs and N-doped CDs are identified by experimental approach. • The emissions of CDs and N-doped CDs are verified by computations. • Such theoretical results are agreeable roughly with the real fluorescence spectra. Nitrogen-doped carbon nano dots (N-doped CDs) caught extensive interests since they usually own higher fluorescent quantum yield (QY) with red-shift emission compared with CDs. However, how was nitrogen element doped into CDs? Which groups in N-doped CDs were responsible for the fluorescent emission? Why did the doping cause red shift? These questions were the keys for understanding the origin of photoluminescence of N-doped CDs, which was obscure until today according to recent publications. Herein, CDs derived from poly(ethylene glycol) were prepared in the first step (emission wavelength = 452 nm; QY = 2.3%). Nitrogen doping was realized conveniently by just reflux heating on CDs and m -phenylenediamine at 70 °C for 3 h. Interestingly, such a facile treatment on CDs aroused significant improvement of the fluorescence (emission wavelength = 516 nm; QY = 36.7%). These N-doped CDs performed very well in cellular imaging of MCF-7. Experimental facts demonstrated the C=C bond and the aldehyde in both CDs and N-doped CDs were the fluorophore that was identical with the CDs prepared with carbohydrates reported in our previous work. Additionally, computations revealed that the partly conjugation of the amide and aromatic ring with fluorescent skeleton of CDs caused the red shift of the emission. [ABSTRACT FROM AUTHOR]

In the process of manufacturing and servicing gas turbine blades, various types of defect are formed and grow rapidly due to the extremely harsh working environment, which poses a huge threat to the safe operation of the gas turbines. Given that different types of defect cause varying degrees of damage to the turbine blades, it is vital to distinguish and deal with defects differently. Considering the shape of the blade (free-form surface) and the location of the defect (inside the blade), digital radiographic imaging can be used for the non-destructive testing of turbine blades. Although some types of defect (for example porosity and cracks) can be distinguished from others (for example voids and inclusions) based on differences in morphological and textural characteristics, others (for example voids and inclusions) may be misclassified due to similarities in morphological and textural characteristics. These defects with similar morphological characteristics are composed of different materials, which can be utilised as a basis for classification. This paper presents a classification method for defects with similar morphological characteristics based on the discrimination of linear attenuation coefficients. Several typical defects, including voids and inclusions, are set into a cuboidal block and into nylon blades in this work. Their corresponding linear attenuation coefficients are obtained. A binary classification of the linear attenuation coefficient enables the categorisation of voids and inclusions. Experimental results demonstrate that the proposed method has high efficiency and the judgement for voids and inclusions is accurate. [ABSTRACT FROM AUTHOR]