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Gamma ray spectrum logging tool acquires reservoir information by detecting gamma ray from formation. It has strict requirements for preservation and use, which is not convenient for college teaching. This paper introduces the design of an analog signal source for gamma ray spectrum logging tool, which generates random number based acceptance-rejection method. These random numbers are converted into electronic pulse signal by data acquisition system. It can simulate the electric pulse signal obtained from gamma ray through stratum. The statistical law of energy spectrum from simulation signal source accords with the probability distribution law of pulse signal generated gamma ray from formation. The analog signal source of gamma ray spectrum logging tool can generate simulation gamma ray logging signal without formation model and radiation source, which is of great value for efficient teaching.

Nanofluids, as an effect additive in oilfield chemistry, has recently attracted significant attention. In this study, the superamphiphobic nanofluid (SAN) was synthesized to be a multi-functional additive in oil based drilling fluid (OBMs). Properties characterization of SAN and its influence on OBMs were investigated. The results showed SAN possessed a spherical shape with a diameter of about 100 nm which could construct a micro-nano structure. Due to the special structure and functional groups (perfluorooctyl) on the particle surface, SAN could alter the shale surface wettability to superamphiphobic, decrease the filtration volume of OBMs, reduce the spontaneous imbibition and maintain the compressive strength of shale core. Furthermore, SAN could exist stably at the interface due to the superamphiphobic characteristic, instead of dispersing in either water or oil phase. Therefore, it enhances the stability of water/oil emulsion. By observing and analyzing the role of SAN in OBMs, it was found SAN could effectively decrease the surface free energy of shale core from 71.47 + 0.52 to 0.09 + 0.02 mN/m and interfacial tension of water/oil system from 32.8–13.5 mN/m, reduce the capillary additional pressure by 1812 Pa and reverse the capillary force from attractive to repulsive. Accordingly, the OBMs with SAN was thought to be able to be used in the drilling of unconventional oil and gas reservoir well, for the considerable stability and that less liquid would penetrate into the shale pore. So the emulsion stability was enhanced and the wellbore stability was maintained. This study might provide an avenue to solve the issues owing to OBMs during the drilling process by adding additives with superamphiphobic wettability.

Neuroinflammation is involved in brain aging and neuronal cell death in neurodegenerative diseases such as Alzheimer's disease (AD). Butein has been suggested to have anti-inflammatory, anti-apoptotic, and anti-cancer effects. However, few studies have been done to evaluate whether butein exerts protective effects on neurons, and the potential mechanism for this effect has not been studied. Here, we examined the effect of butein on SH-SY5Y neuroblastoma cells grown with conditioned medium from BV2 microglia cells that had been activated by lipopolysaccharide (LPS) as a neuroinflammation model. We found butein pretreatment significantly increased SH-SY5Y cell viability in a dose-dependent manner by inhibiting the apoptosis normally induced by microglia-conditioned medium. SH-SY5Y cells treated with microglia-conditioned medium showed upregulated ERK signaling pathway-related mRNA expression and protein phosphorylation, which was dose-dependently reversed by butein. Immunocytochemistry and Western blot results showed that BV2-LPS conditioned medium-induced Nuclear factor kappaB (NF-κB) transactivational activity in SH-SY5Y cells, but this was attenuated by butein treatment of the BV2 cells prior to their exposure to LPS. Collectively, our results indicate that butein effectively mitigates inflammatory injury caused by LPS-conditioned medium from microglia, possibly due to reductions in the transactivational activity of NF-κB p65 and ERK signaling pathway activation, and provide evidence for a neuroprotective role of butein through blocking negative consequences of microglial activation.

The emergency of ubiquitous intelligence in various things has become the ultimate cornerstone in building a smart interconnection of the physical world and the human world, which also caters to the idea of Internet of Things (IoT). Nowadays, robots as a new type of ubiquitous IoT devices have gained much attention. With the increasing number of distributed multi-robots, such smart environment generates unprecedented amounts of data. Robotic applications are faced with challenges of such big data: the serious real-time assurance and data privacy. Therefore, in order to obtain the big data values via knowledge sharing under the premise of ensuring the real-time data processing and data privacy, we propose a real-time data processing architecture for multi-robots based on the differential federated learning, called RT-robots architecture. A global shared model with differential privacy protection is trained on the cloud iteratively and distributed to multiple edge robots in each round, and the robotic tasks are processed locally in real time. Our implementation and experiments demonstrate that our architecture can be applied on multiple robotic recognition tasks, balance the trade-off between the performance and privacy.

The remote sensing detection is a challenging issue for scale diversity, diversity of views, small objects, and sophisticated light and shadow backgrounds. In this paper, inspired by the state-of-the-art detection framework FPN [6], we propose a novel approach for constructing a feature fusion mode that optimizes feature context utilization in detection, calling our resulting system LFFN for Layer-weakening Feature Fusion Network. We explore the inherent relevance of different layers to the final decision, as well as the incentives of higher-level features to lower-level features. Based on the experiments on the remote sensing dataset from Google Earth, our approach has proved effective and practical for remote sensing detection, achieving 89% mAP which is 4.1% higher than that of FPN, running at 4 to 6 FPS.

Following trails in the wild is an essential capability of out-door autonomous mobile robots. Recently, deep learningbased approaches have made great advancements in this field. However, the existing research only focuses on the trail following with a single robot. In contrast, many robotic tasks in the reality, such as search and patrolling, are conducted by a group of robots. While these robots are grouped to move in the wild, they can cooperate to significantly promote the trail following accuracy, for example, by sharing images of different view angles or real-time decision fusion. This paper proposes such an approach named DL-Cooper that enables multi-robot visionbased trail following based on deep learning algorithms. It allows each robot to make a decision respectively with deep neural network and then fusion the decisions on the collective level with the support of back-end cloud computing infrastructure. It also takes Quality of Service (QoS) assurance, a very essential property of robotic software, into consideration. By limiting the condition to fusion decisions, the time latency can be minimally sacrificed. Experiments on the real-world dataset show that our approach has significantly improved the accuracy of the singlerobot system.

This paper investigates a consensus algorithm-based power dispatch problem when the power outage happens in the intelligent household. Energy storage devices are added in power grids to support the electricity supply while taking power outages into consideration. According to the need of using electrical appliances caused by the different power outage periods lengths, the establishment of smart home load model and the load shedding judgment are proposed. When the different energy storage devices are used to provide electricity, a consensus algorithm is proposed for the power dispatch. Finally, an example is given to illustrate the effectiveness of proposed algorithm.

Post-fire succession is an ideal case for studying effects of disturbance on community assembly, and the key is to disentangle the contributions of assembly processes to the variation of community composition, namely beta diversity, and the contingent scales. The central Yunnan Plateau of Southwest China is characterized by monsoon related seasonal drought, and frequent forest fires. We sampled five fire sites burned in different years and a middle aged forest, measured species composition dissimilarity and its species turnover and nestedness components, within each fire site and across all sites. Results indicated species turnover as the primary component of beta diversity within all communities. There was no trend of change with year-since-fire (YSF) in beta diversity among early post-fire communities, but beta diversity in the middle aged community was significantly higher. Species turnover patterns across fire sites revealed a weak dispersal limit effect, which was stronger at lower than upper slope position for woody plants, and reverse for herbs. At the site scale, the species dissimilarity and turnover both enlarged with increasing slope position difference, especially in the middle-aged community, but the species nestedness had no consistent trend among sites, except a decreasing trend in the middle-aged forest. (Partial) Mantel tests indicated habitat filtering [primarily indicating total nitrogen (TN) and slope position] played a much stronger role than dispersal limit and YSF (indicating competition intensity) for the post-fire forest assembly at the landscape scale, for both woody and herbaceous layers. However, at the site scale, Mantel tests indicated a diminishing effect of soil nutrient filtering with increasing YSF, while effects of topography and spatial distance in the middle aged community was stronger. This divergence suggests the primary assembly mechanism gradually shift away from the soil constraint. While the seasonal drought and the mountain topography dominate the environmental legacy, our results imply that fires may reinforce a priority effect in the forests assembly in this region, by creating a habitat filtering (e.g., moisture and nitrogen limitation) effect on species composition in post-fire communities.

Micro RNAs (miRNAs) are small non-coding RNAs which are 19-24 nucleotides in length. MiRNAs play a vital role in the whole process of tumour development, but how they influence the tumourigenecity of epithelial ovarian cancer (EOC)cells is rarely researched. In our study, it was verified that miR-628-5p decreased the stem like cell percentage of EOC cells by inducing their apoptosis. The animal experiments showed that miR-628-5p decreased the tumourigenecity of EOC cells. Besides, we found miR-628-5p targeted at and down-regulated the expression of fibroblast growth factor receptor 2 (FGFR2). FGFR2 expressed higher in ovarian cancer tissues and was correlated with worse prognosis. Our findings indicated that miR-628-5pplays an important role in ovarian cancer stem cell driven tumorigenesis.

Epithelial ovarian cancer (EOC) is highly metastatic and current therapeutics are unsatisfactory. Cancer stem/stem-like cells (CSCs/CSCLs) represent a rare population of undifferentiated oncogenic cells responsible for tumor initiation and maintenance. We identified ovarian cancer ALDHhigh (aldehyde dehydrogenase) population could perform not only strengthened CSCLs properties embodied in colony-formation, CSCs-markers expression, and tumorigenesis in vivo, but also a greater invasive capacity with advanced EMT progress and anti-apoptosis compared with ALDHlow cells. Furthermore, both the stemness and aggressive features, along with ALDHhigh percentages were in positive association with the invasiveness of cell lines for sorting, indicating the promotive role of ALDHhigh CSCLs in EOC neoplasia and metastasis, since the whole tumor was derived from the CSCLs with hyperactive self-renewal and aggression. Collectively, this study illustrates the interplay between ALDHhigh CSCLs and EOC invasion, and offers a novel application target for the EOC oncotherapy.

Summary Emerging evidence indicates a link between the increased proportion of regulatory T cells (Tregs) and reduced survival in patients who have been diagnosed with cancer. Cancer stem cells (CSCs) have been indicated to play a vital role in tumour initiation, drug resistance and recurrence. However, the relationship between Tregs and CSCs remains largely unknown. Here, we sorted out ovarian cancer stem-like side population (SP) cells and CD133+ cells to investigate the influence of ovarian CSCs on Tregs. Among the various immune-related molecules that we assessed, C-C motif chemokine ligand 5 (CCL5) was the most elevated in ovarian CSCs relative to that in the non-CSCs. The expression of its receptor, C-C motif chemokine receptor 5 (CCR5), was also increased on the surface of Tregs in ovarian cancer patients. This receptor-ligand expression profile indicated that ovarian CSCs recruit Tregs via CCL5–CCR5 interactions. We further assessed the expression of interleukin (IL)-10 in Tregs cultured with different cancer cells. Tregs cultured in conditioned medium (CM) from ovarian CD133+ cells expressed a higher level of IL-10 than Tregs cultured in CM from CD133– cells, indicating that Tregs exert pronounced immune-inhibitory functions in CSC-rich environments. Furthermore, co-culture with ovarian cancer cell lines induced the expression of matrix metalloproteinase-9 (MMP9) in Tregs which, in turn, enhanced the degradation of the extracellular matrix and enabled the invasion of tumour cells, thereby facilitating tumour metastasis. For the first time, to our knowledge, our findings describe the relationship between ovarian CSCs and Tregs, and demonstrated that these two cell populations co-operate to promote tumour immune tolerance and enhance tumour progression.

Molecular orientations and energy levels at organic interfaces are critical knowledge in guiding materials selections in organic electronic device design. The correlation between molecular orientations and the energy levels when two different molecules are placed in contact with each other is discussed. Several combinations of different organic semiconducting molecules are investigated here with a broad range of structures. In-situ ultraviolet photoemission spectroscopy (UPS) is used to directly probe the energy levels at the molecular interfaces.

To analyze mutations of IDUA gene in two pedigrees affected with mucopolysaccharidosis type I and provide prenatal diagnosis for them.The 14 exons of the IDUA gene were subjected to PCR amplification and Sanger sequencing.For pedigree 1, the proband was found to harbor compound heterozygous mutations c.46-57delTCGCTCCTGGCC (p.Ser16_Ala19del) of exon 1 and c.1147delC (p.Arg383Alafs*57) of exon 8 of the IDUA gene, which were inherited from his father and mother, respectively. The latter was unreported previously. Prenatal diagnosis suggested that the fetus has carried a heterozygous c.46-57delTCGCTCCTGGCC mutation. For family 2, the proband was also found to carry compound mutations of the IDUA gene, namely c.721T to C (p.Cys241Arg) of exon 6 and c.1491delG (p.Thr497fs27) of exon 8, which were inherited from her mother and father, respectively. Neither mutation was reported previously. Prenatal diagnosis suggested that the fetus has carried a heterozygous c.721T to C mutation.Mutations of the IDUA gene probably underlie the MPS-I in both pedigrees. Above results have enriched the spectrum of IDUA gene mutations and facilitated prenatal diagnosis for both families.

Transcription factors (TFs), which play a vital role in regulating gene expression, are prevalent in all organisms and characterization of them may provide important clues for understanding regulation in vivo. The present study reports a genome-wide investigation of TFs in the diamondback moth, Plutella xylostella (L.), a worldwide pest of crucifers. A total of 940 TFs distributed among 133 families were identified. Phylogenetic analysis of insect species showed that some of these families were found to have expanded during the evolution of P. xylostella or Lepidoptera. RNA-seq analysis showed that some of the TF families, such as zinc fingers, homeobox, bZIP, bHLH, and MADF_DNA_bdg genes, were highly expressed in certain tissues including midgut, salivary glands, fat body, and hemocytes, with an obvious sex-biased expression pattern. In addition, a number of TFs showed significant differences in expression between insecticide susceptible and resistant strains, suggesting that these TFs play a role in regulating genes related to insecticide resistance. Finally, we identified an expansion of the HOX cluster in Lepidoptera, which might be related to Lepidoptera-specific evolution. Knockout of this cluster using CRISPR/Cas9 showed that the egg cannot hatch, indicating that this cluster may be related to egg development and maturation. This is the first comprehensive study on identifying and characterizing TFs in P. xylostella. Our results suggest that some TF families are expanded in the P. xylostella genome, and these TFs may have important biological roles in growth, development, sexual dimorphism, and resistance to insecticides. The present work provides a solid foundation for understanding regulation via TFs in P. xylostella and insights into the evolution of the P. xylostella genome.

Organo-metal halide perovskites are a promising platform for optoelectronic applications in view of their excellent charge-transport and bandgap tunability. However, their low photoluminescence quantum efficiencies, especially in low-excitation regimes, limit their efficiency for light emission. Consequently, perovskite light-emitting devices are operated under high injection, a regime under which the materials have so far been unstable. Here we show that, by concentrating photoexcited states into a small subpopulation of radiative domains, one can achieve a high quantum yield, even at low excitation intensities. We tailor the composition of quasi-2D perovskites to direct the energy transfer into the lowest-bandgap minority phase and to do so faster than it is lost to nonradiative centers. The new material exhibits 60% photoluminescence quantum yield at excitation intensities as low as 1.8 mW/cm2, yielding a ratio of quantum yield to excitation intensity of 0.3 cm2/mW; this represents a decrease of 2 orde...

The tunable bandgap of colloidal quantum dots (CQDs) makes them an attractive material for photovoltaics (PV). The best present-day CQD PV devices employ zinc oxide (ZnO) as an electron transport layer; however, it is found herein that ZnO's surface defect sites and unfavorable electrical band alignment prevent devices from realizing their full potential. Here, chloride (Cl)-passivated ZnO generated from a solution of presynthesized ZnO nanoparticles treated using an organic-solvent-soluble Cl salt is reported. These new ZnO electrodes exhibit decreased surface trap densities and a favorable electronic band alignment, improving charge extraction from the CQD layer and achieving the best-cell power conversion efficiency (PCE) of 11.6% and an average PCE of 11.4 ± 0.2%.

In this work, a direct C–H activation of thiophenes was presented via an oxidation pathway under visible-light irradiation, in which the thiophene radical cation serves as the key intermediate. Various thiophenes and azoles could be transformed into the corresponding amination products well, and H2O was the only byproduct which is environmentally benign. Our results showed that tert-butyl nitrite (TBN) served as the electron transfer mediator and O2 as the terminal oxidant to regenerate the photocatalyst DDQ and revive the photocatalytic cycle.

To detect potential mutation of iduronate-2-sulfatase (IDS) gene in a family affected with mucopolysaccharidosis type Ⅱ (MPS Ⅱ).For the proband and his unaffected mother, the whole coding sequence of the IDS gene was analyzed with PCR and bidirectional Sanger sequencing.A novel splicing mutation, c.709-1GA, was detected in the proband, for which his mother was heterozygous.The c.709-1GA splicing mutation of the IDS gene is probably causative for the MSP Ⅱ in the proband. Prenatal diagnosis for the mutation may avoid birth of further child affected with this disease.

An organic semiconductor thin film is a solid-state matter comprising one or more molecules. For applications in electronics and photonics, several distinct functional organic thin films are stacked together to create a variety of devices such as organic light-emitting diodes and organic solar cells. The energy levels at these thin-film junctions dictate various electronic processes such as the charge transport across these junctions, the exciton dissociation rates at donor-acceptor molecular interfaces, and the charge trapping during exciton formation in a host-dopant system. These electronic processes are vital to a device's performance and functionality. To uncover a general scientific principle in governing the interface energy levels, highest occupied molecular orbitals, and vacuum level dipoles, herein a comprehensive experimental research is conducted on several dozens of organic-organic heterojunctions representative of various device applications. It is found that the experimental data map on interface energy levels, after correcting variables such as molecular orientation-dependent ionization energies, consists of three distinct regions depending on interface fundamental physical parameters such as Fermi energy, work function, highest occupied molecular orbitals, and lowest unoccupied molecular orbitals. This general energy map provides a master guide in selection of new materials for fabricating future generations of organic semiconductor devices.

Xyloketals, a new type of antioxidants from a marine mangrove fungus, have potential pharmacological properties. In this paper, the radical-scavenging activities of a series of synthetic xyloketals and related chromanes toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) were evaluated by absorption spectrometry. One of the compounds (compound 10 ) displayed significant antioxidative action against DPPH and ABTS. A structure-activity analysis showed that the reactive sites on these compounds correlated with a hydroxy-group and also with ketal or aromatic H substituents. Based in part on a density functional theory (DFT) calculation of compound 10 , the antioxidant mechanism of this chromane was deduced as a possible radical-scavenging mechanism by a sequential proton loss electron-transfer (SPLET) process.

Direct cross-coupling between alkenes/R-H or alkenes/RXH is a dream reaction, especially without external oxidants. Inputting energy by photocatalysis and employing a cobalt catalyst as a two-electron acceptor, a direct C-H/X-H cross-coupling with H2 evolution has been achieved for C-O and C-N bond formation. A new radical alkenylation using alkene as the redox compound is presented. A wide range of aliphatic alcohols-even long chain alcohols-are tolerated well in this system, providing a new route to multi-substituted enol ether derivatives using simple alkenes. Additionally, this protocol can also be used for N-vinylazole synthesis. Mechanistic insights reveal that the cobalt catalyst oxidizes the photocatalyst to revive the photocatalytic cycle.

Transition-metal mediated C-S bond formation using thiol compounds has been widely used in recent years. However, there has been less focus on the interaction between the metal and thiol compounds. In this work, we have successfully evidenced the single-electron transfer between CuX

Robots have been widely adopted to perform critical tasks in various fields in the past several years. Due to the limitations of its local resources, the capability of a single robot is usually severely restricted. Cloud robotics has been recently proposed to extend the capability of robots by leveraging the rich services provided in cloud. However, robotic applications generally give considerable attention to quality of service (QoS) because these applications interact directly with the physical world. Fulfilling strict QoS requirements while utilizing cloud services, the performance of which is highly unpredictable, is a great challenge. In this paper, we propose a novel hybrid architecture for cloud robotics, named RoboCloud, to address this challenge. Instead of simply integrating robots with public cloud services, RoboCloud introduces a task-specified mission cloud with controllable resources, predictable behavior. The mission cloud can extend the capability of the robot on its specified, predictable tasks without sacrificing QoS. For general tasks beyond the capability of the mission cloud, we opt for public clouds, i.e., various cloud services available on the Internet. We successfully apply this architecture to realize robotic object recognition, which is a fundamental capability of autonomous robots who interact with an open environment. We can minimize the recognition latency of objects that are predicted to appear in a specific task without sacrificing the capability to recognize unfamiliar, unexpected objects by seamlessly integrating a specialized mission cloud, a public object recognition service on the Internet.

As The integration of Physical space and cyberspace, the large-scale data distributing to diversification terminal which is geographical distribution of mass has become a huge challenge. When the data size can't be processed by the technology for traditional scope, how to deal with the user quality of service and efficient use of system resources has become an important issue of concern, with the resources becoming limited. This paper presents a data-driven mechanism for large-scale data distribution which is consists of four core part of the data production, data collection and pre-processing, data analysis engine, data consumption, aims to excavate the valuable information to improve the efficiency of resource use and accurate fault location for the Large-scale data distribution system. At the same time, this paper studies the resource scheduling optimization with analyzing data driven for the system behavior and Fault location with analyzing data-driven environment, which proves the effectiveness for the operation of the Large-scale data distribution system optimization by the data-driven working.

TiO2 has excellent electrochemical properties but limited solar photocatalytic performance in light of its large bandgap. One important class of visible-wavelength sensitizers of TiO2 is based on ZnFe2 O4 , which has shown fully a doubling in performance relative to pure TiO2 . Prior efforts on this important front have relied on presynthesized nanoparticles of ZnFe2 O4 adsorbed on a TiO2 support; however, these have not yet achieved the full potential of this system since they do not provide a consistently maximized area of the charge-separating heterointerface per volume of sensitizing absorber. A novel atomic layer deposition (ALD)-enhanced synthesis of sensitizing ZnFe2 O4 leaves grown on the trunks of TiO2 trees is reported. These new materials exhibit fully a threefold enhancement in photoelectrochemical performance in water splitting compared to pristine TiO2 under visible illumination. The new materials synthesis strategy relies first on the selective growth of FeOOH nanosheets, 2D structures that shoot off from the sides of the TiO2 trees; these templates are then converted to ZnFe2 O4 with the aid of a novel ALD step, a strategy that preserves morphology while adding the Zn cation to achieve enhanced optical absorption and optimize the heterointerface band alignment.

Silicon nanocrystals (ncSi) displaying size‐dependent optoelectronic properties functionalized with cationic surface groups are synthesized through a versatile alkyl‐halide surface intermediate. In article number 1500263, together with anionic functionalized ncSi developed by the same group, G. A. Ozin and co‐workers envision numerous combinations to observe the interplay between large and small, cationic and anionic silicon nanocrystals.

Through the establishment of water on the surface of the heat loss and the bathtub wall heat loss of the two models to analysis heat bath total loss, as the foundation to find a most suitable strategy the person in the bathtub can adopt. Model of heat loss through water surface discuss the heat loss between the water surface and air. Model of heat loss through wall developed by Newton's law(1), analysis the heat loss through bathtub wall. The two reflects the reason why people are difficult to maintain a constant water temperature when taking a bath.

The latest advances in colloidal-quantum-dot material processing are combined with a double-sided junction architecture, which is done by efficiently incorporating indium ions in the ZnO eletrode. This platform allows the collection of all photogenerated carriers even at the maximum power point. The increased depletion width in the device facilitates full carrier collection, leading to a record 10.8% power conversion efficiency.

A mild and efficient protocol for the synthesis of the benzopyran ring has been described and a series of chromans compounds is reported, the yield is from 72% to 95%. The diadduct tended to angular product and showed good regioselectivity. This strategy was applied for the benzopyran derived natural products (±)-xyloketals and (±)-alboatrin. The crystal of compound 9 exhibited centro-symmetric space group, containing two isomers in one unit. The relative configurations were 1R,10R,15S and 34S,22R,30S, respectively.

Energy and agricultural commodities and markets have been examined extensively, albeit separately, for a number of years. In the energy literature, the returns, volatility and volatility spillovers (namely, the delayed effect of a returns shock in one asset on the subsequent volatility or covolatility in another asset), among alternative energy commodities, such as oil, gasoline and ethanol across different markets, have been analysed using a variety of univariate and multivariate models, estimation techniques, data sets, and time frequencies. A similar comment applies to the separate theoretical and empirical analysis of a wide range of agricultural commodities and markets. Given the recent interest and emphasis in bio-fuels and green energy, especially bio-ethanol, which is derived from a range of agricultural products, it is not surprising that there is a topical and developing literature on the spillovers between energy and agricultural markets. Modelling and testing spillovers between the energy and agricultural markets has typically been based on estimating multivariate conditional volatility models, specifically the Baba, Engle, Kraft, and Kroner (BEKK) and dynamic conditional correlation (DCC) models. A serious technical deficiency is that the Quasi-Maximum Likelihood Estimates (QMLE) of a Full BEKK matrix, which is typically estimated in examining volatility spillover effects, has no asymptotic properties, except by assumption, so that no valid statistical test of volatility spillovers is possible. Some papers in the literature have used the DCC model to test for volatility spillovers. However, it is well known in the financial econometrics literature that the DCC model has no regularity conditions, and that the QMLE of the parameters of DCC has no asymptotic properties, so that there is no valid statistical testing of volatility spillovers. The purpose of the paper is to evaluate the theory and practice in testing for volatility spillovers between energy and agricultural markets using the multivariate Full BEKK and DCC models, and to make recommendations as to how such spillovers might be tested using valid statistical techniques. Three new definitions of volatility and covolatility spillovers are given, and the different models used in empirical applications are evaluated in terms of the new definitions and statistical criteria.

A great number of functional organic molecules in active thin-film layers of optoelectronic devices have highly asymmetric structures, such as plate-like, rod-like, etc. This makes molecular orientation an important aspect in thin-films as it can significantly affect both the optical and electrical performance of optoelectronic devices. With a combination of in-situ ultra violet photoelectron spectroscopy (UPS) and x-ray photoelectron spectroscopy (XPS) investigations for organic molecules having a broad range of structural properties, we discovered a rigid connection of core levels and frontier highest occupied molecular orbital levels at organic interfaces. This finding opens up opportunities of using X-ray photoemission spectroscopy as an alternative tool to UPS for providing an easy and unambiguous data interpretation in probing molecular orientations.

In this report, the synthesis of a novel class of cationic quaternary ammonium-surface-functionalized silicon nanocrystals (ncSi) using a novel and highly versatile terminal alkyl halide-surface-functionalized ncSi synthon is described. The distinctive features of these cationic ncSi include colloidal stability, pH-independent positive surface charge, and size-tunable photoluminescence (PL) in the biologically relevant near-infrared-to-red spectral region. These cationic ncSi are characterized via a combination of high-resolution scanning transmission electron microscopy with energy-dispersive X-ray analysis, Fourier transform infrared, X-ray photoelectron, and photoluminescence spectroscopies, and zeta potential measurements.

Energy offset (EDA) from a number of donor/acceptor heterojunctions is measured using ultraviolet photoemission spectroscopy. It is found that substrate work functions have little impact on the energy level alignments at donor/acceptor heterojunctions. Planar-heterojunction organic photovoltaic cells are made to test the relationship between energy offset and open-circuit voltage (VOC). VOC is found to increase linearly as a function of EDA. The VOC, however, takes a surprising turn at EDA = 1.5 eV and starts to decrease as a function of donor–acceptor energy levels. To explain this experimental observation, a theoretical model to quantify the relationship between VOC and EDA is developed. The proposed model well explains the experimental data and, in particular, the reverse trend of VOC on EDA. By grouping several material constants into one variable, a simple universal plot that well describes the experimental data for both planar-heterojunction and bulk-heterojunction cells is generated.

Introduction Recanalisation of intracranial aneurysms following endovascular treatment is a major issue. Many factors, including aneurysm morphology, the method of treatment, and haemodynamics, are considered to be associated with recanalisation. However, the underlying haemodynamic mechanisms are not completely understood. Methods and analysis This is a prospective, observational, registry study for patients with intracranial aneurysms who are treated endovascularly. It will enrol 200 eligible patients. Data on morphological, haemodynamic, and treatment factors will be collected prospectively. The advanced virtual stenting technique and porous media method will be used in haemodynamic simulations. The clinical and angiographic outcomes at 6 months will be measured and analysed. This observational study will determine the haemodynamic factors that affect the recanalisation of aneurysms. Ethics and dissemination Both the study protocol and written informed consent were reviewed and approved by the Institutional Review Board of Beijing Tiantan Hospital (KY2016-023-01). The results of study will be disseminated in professional printed media. Trial registration number NCT02812108; Pre-results.

Epithelial ovarian carcinoma (EOC) is a lethal gynecological malignancy. Epithelial-mesenchymal transition (EMT) has an important role in the tumorigenesis and progression of EOC. During the process of EMT, the transforming growth factor-β (TGF-β)-Smad signaling pathway has been indicated to regulate cell motility and tumor development. Among numerous EMT-associated transcripts, Smad7 is considered to be an inhibitor, however its involvement together with TGF-β1 in the progression of ovarian cancer remains to be elucidated. The present study demonstrated that Smad7 was overexpressed in SK-OV-3 and stem-like side populations of EOC cells, both of which grow in an epithelial pattern. The transformation of cells from an epithelial to a mesenchymal phenotype was stimulated by TGF-β1 with a corresponding increase in Smad7 expression in SK-OV-3 cells. These results indicate that Smad7 is a regulator in the maintenance of the epithelial phenotype in EOC cells, and may serve as an inhibitory element which targets TGF-β-stimulated EMT. Furthermore, inhibition of Smad7 resulted in cellular mesenchymal transformation, with an increased expression of N-cadherin and a decreased expression of E-cadherin. The invasiveness and migratory capabilities of Smad7 small hairpin RNA transduced EOC cells was also reduced. The findings of the present study have identified Smad7 as a fundamental factor in the maintenance of epithelial growth of EOC cells. Reversal of EMT results in a mesenchymal-epithelial transition, which is necessary for EOC cell colonization at metastatic sites.

Paraneoplastic cerebellar degeneration associated with gynecological and breast malignancies (PCD) is known to develop autoantibodies and autoreactive cytotoxic T lymphocytes (CTLs) specific for a cytoplasmic protein of Purkinje cells PCD17/cdr2, in the blood of patients. The functional roles of these antibodies and CTLs in the pathogenesis of PCD are unknown. Induction of immune response to this antigen in experimental animals should be useful to clarify the immune mechanisms in PCD patients. We immunized Balb/c mice with naked DNA, which is encoded human PCD17 neural protein in an eukaryotic expression plasmid under control of CMV promoter, and explored whether or noth humoral and cell-mediated immune responses against PCD17 could be induced in vivo . We show that DNA immunization with nake pcd17 cDNA could induce autoantibodies against the cytoplasmic protein of Purkinje cells and CTLs could lyse syngenic myeloma cells pulsed with H-2K-restricted PCD17 peptide. In spite of the generation of anti-Purkinje cell antibodies and PCD17-specific CTLs in vivo , neither clinical nor pathological changes consistent with significant cerebellar degeneration have been detected.