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Purpose This research aims to provide a theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and V-shaped substrate, which also gives guidance for those complicated welding operation objects in brazing technique. Design/methodology/approach Wetting experiments were performed to measure the contact angles at different temperatures of molten Sn-3.0Ag-0.5Cu wetting on the quartz substrate with an included angle of 90°. According to the experimental results, the theoretical spreading morphology of molten solder on V-shaped substrate at corresponding temperature was simulated by Surface Evolver. Findings The theoretical morphology profiles of the molten solder sitting on the V-shaped substrate are simulated using Surface Evolver when the molten solder reaches spreading equilibrium. The spreading mechanisms as well as the impact of surface tension and gravity on interfacial energy of the molten solder wetting on the V-shaped groove substrate are also discussed where theoretical results agree well with experiment results. The contact area between the gas and liquid phases shows a tendency of first increasing and later decreasing. Otherwise, the spreading distance and the height of the molten solder increases as the droplet volume increases as the included angle and the contact angle are given as constants, and both the interfacial energy and the gravitational energy increase as well. This research has a wide influence on predicting the outcomes in commercial impact and also gives guidance for those complicated welding operation objects in brazing technique. Research limitations/implications It is of very important significance in both science and practice to investigate the differences between the flat surface and V-shaped surface. Some necessary parameters including intrinsic contact angle and surface tension need to be directly measured when the droplet spreads on the flat surface. The relevant simulation conclusions on the inherent characteristics can be given based on these intrinsic parameters. Compared with the flat surface, the V-shaped substrate is chosen for further discuss on the effects of gravity on the droplet spreading behavior and the changes of apparent contact angle which can only occurs as the substrate is inclined. Therefore, this research provides theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and substrate. Practical implications The research is developed for verifying the accuracy of the model built in Surface Evolver. Based on this verified model, other researches on the spreading distance along y-axis and the contact area that are especially difficult to be experimentally measured can be directly simulated by Surface Evolver, which can provides a convenient method to discuss the changes of horizontal spreading distance, droplet height and contact area with increasing the included angle of V-shaped substrate or with increasing the droplet volume. Actually, the modeling results are calculated for supplying the theoretical parameters and technical guidance in the welding process. Social implications This research provides theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and substrate, which has a wide influence on prediction the outcomes in commercial impact and also gives guidance for those complicated welding operation objects in brazing technique. Originality/value Surface Evolver, can also be used to discuss the structure and spreading mechanism of droplets on V-shaped substrates, which have not been discussed before.

Currently, it is not entirely clear whether hypoxia-inducible factor-1α (HIF-1α) is involved in the regulation of COX-2 expression and epithelial-to-mesenchymal transition (EMT), and whether these events affect the prognosis of hepatocellular carcinoma (HCC) patients treated with transcatheter arterial chemoembolization (TACE). In this report the relationship between HIF-1α and COX-2 protein expression, EMT in tumor specimens from HCC patients after TACE surgery and the clinical significance of HIF-1α and COX-2 expression were analyzed using statistical approaches. HepG2 cells treated with CoCl2 was employed as a hypoxia cell model in vitro to study hypoxia-induced HIF-1α, COX-2 expression, and EMT alteration. The results showed that HIF-1α and COX-2 protein expression increased in HCC tissues after TACE surgery. Moreover, there was positive correlation between upregulation of HIF-1α and COX-2. Elevated expression of HIF-1α increased both Snail and Vimentin protein expression, while it reduced E-cadherin protein expression. It was further verified that hypoxia enhanced protein expression of HIF-1α and COX-2 in HepG2 cells treated with CoCl2. Upregulation of HIF-1α and COX-2, together with EMT alteration resulted in increased migration and invasion of HepG2 cells under hypoxia. In conclusion, TACE surgery results in aggravated hypoxia status, leading to increased HIF-1α protein expression in HCC tissue. To adapt to hypoxic environment, HIF-1α stimulates COX-2 protein expression and promotes EMT process in hepatocellular cancer cells, which enhances HCC invasion and metastasis, and might contribute to poor prognosis in HCC patients post TACE treatment.

Objectives To investigate the survival benefit of transarterial chemoembolization (TACE) plus Iodine125 seed implantation (TACE-Iodine125) in hepatitis B-related HCC patients with portal vein tumour thrombus (PVTT) and the underlying prognostic factors. Methods A retrospective matched cohort study was performed on consecutive HCC patients with PVTT from January 2011 to June 2014. Seventy patients (TACE-Iodine125 group) who underwent TACE-Iodine125 were compared with a historical case-matched control group of 140 patients (TACE group) who received TACE alone. The survival of patients and the underlying prognostic factors were analysed. Results The median survival times of the TACE-Iodine125 and TACE groups were 11.0 and 7.5 months, respectively (p

The effects of Bi addition on the properties of Sn-3.0Ag-0.5Cu molten alloy on Cu substrates are discussed using wettability and interface microstructure analysis. The changes of the contact angles between Sn-3.0Ag-0.5Cu-xBi and Cu substrates with the spreading time are described by Dezellus model. It indicates that the spreading process is governed by the interfacial reaction during the dwelling time. The interface microstructure is observed to clarify the effects of reactions on the spreading behavior. It is found that Cu6Sn5 is formed adjacent to the solder and Cu3Sn appears over the substrate with Bi added at 613K, indicating that Bi exists between the intermetallics and the addition of Bi can hinder the diffusion of copper towards the interior of the solder. Therefore the existence of Bi decreases the agglomeration of Cu-Sn grains. The growth of intermetallics is thus limited and the shape of intermetallics transforms from scallop to zigzag consequently. However, the segregation phenomenon appears when the additive amount of Bi is more than 5.5mass %, which could lead to the occurrence of fracture and degrade the performance of Sn-3.0Ag-0.5Cu-xBi alloy. The results of the present study provide basic physical and chemical data for the application of lead-free solder in the future microgravity space environment.

A hybrid featuring the CuInS 2 quantum dots (CuInS 2 -QDs) on reduced graphene oxide (rGO) sheets is synthesized by a facile one-pot solvothermal approach with thiourea as S source, in which graphene oxide (GO) sheets are reduced into rGO sheets in course of the CuInS 2 -QDs aggregate growth. The growth mechanism of the hybrid is elucidated. It is found that adsorption of Cu 2+ cations mainly takes place at epoxy/hydroxyl groups on GO sheets at room temperature and the adsorbed Cu + cations resulting from the Cu 2+ reduction at solvothermal temperature act as the nucleation for the surface growth of CuInS 2 -QDs into three-dimensional aggregates on GO sheets that are simultaneously reduced into rGO sheets. Our results demonstrate that the rGO/CuInS 2 -QDs hybrid is an effective electron acceptor with a complementary absorption property for polymer-based solar cells. The solar cells based on rGO/CuInS 2 -QDs hybrid and poly(1-methoxy-4-(2-ethylhexyloxy)-p-phenylene vinylene) exhibit an efficiency of 1.5%, much higher than the counterpart devices of rGO sheets. The effects of CuInS 2 -QDs aggregates on device performance are discussed. In the long run, this work provides a potential hybrid electron acceptor for low-cost and efficient solar cell fabrication.

The accumulation of H at the small-angle tilt grain boundary (GB) in the W(001) surface is investigated, on the basis of the first-principles calculations. By exploring the solution and diffusion behaviors of H at the GB, we find that the small-angle GB can capture the H atoms nearby, serving as a nucleation site of H bubbles. With the increasing number of trapped H atoms, the GB expands gradually, and the GBs can be unripped with an areal density of H up to 5.0 × 1015 H atoms per cm2, leading to the formation of H bubbles. Moreover, H2 molecules are observed, when the areal density of H atoms in GB is over 6.6 × 1015 atoms per cm2. According to our calculations, we propose a possible formation mechanism of H bubbles observed in the experiment, which is valuable for improving the service performance of W as a plasma-facing material in nuclear fusion reactors.

This paper addresses trajectory tracking control problem for autonomous underwater vehicles (AUVs) using quaternion-based attitude representation. A quaternion based adaptive non-singular terminal sliding mode control scheme is proposed for an AUV subject to ocean current and modelling uncertainty. At first, kinematic equations of the translational and rotational motions are described by unit quaternions. And then, a class of modified non-singular terminal sliding mode surface is developed by smoothly switching into a non-singular sliding mode surface formed by sinusoidal functions when the tracking error reaches a small range of the origin. The finite-time convergences of both the position tracking error and quaternion error are proved based on Lyapunov theory. Finally, the proposed control scheme is applied on a typical fully-actuated AUV to perform simulations. And the simulation results illustrate the effectiveness of the proposed control scheme in comparison with another terminal sliding mode control algorithm.

In this paper, multivariable sign transfer entropy algorithm is used to calculate the multivariable sign transfer entropy values of the same brain region and different brain regions stimulated by different emotional images in patients with depression and healthy control group. The connectivity of the magnetic channels in the brain region and between brain regions is studied. And the conclusions of negative cognitive bias in depressed patients [1] and functional asymmetry of emotion of cerebral hemispheres are verified [2]. The results showed that: For different brain regions, the left occipital region →frontal region under positive emotional picture stimulation and neutral emotional picture stimulation can significantly distinguish the depressed patients’ group from the healthy control group, the corresponding connection strength of depressed patients was significantly weaker than that of healthy control group.

Magnetoencephalography (MEG) is a kind of brain function detection technology without trauma, which detects the electromagnetic physiological signal in the brain. It is widely used in depression research. We used permutation entropy, improved permutation entropy, conditional entropy to study the difference of MEG between depressed patients and healthy people, respectively. We implement three different entropy algorithms and compare the relative differences of entropy values in different brain regions of healthy people and depression patients under positive, neutral and negative emotional stimuli. The experimental results show that the relative difference of conditional entropy > the relative difference of improved permutation entropy > the relative difference of permutation entropy, and the difference of entropy value in the frontal region of human brain is the most obvious, which may provide the basis for the diagnosis of depression.

We use the information entropy based on linear model, K-nearest neighbour estimation and kernel estimation to study the brain, a complex nonlinear dynamic system, and distinguish the nonlinear dynamic complexity of epileptic and normal EEG signals in Bonn database. The entropy estimation method of linear model and K-nearest neighbour estimation can only distinguish the information entropy of epileptic period from that of other two cases, but it can’t distinguish the information entropy of epileptic interval and normal EEG signals. However, kernel estimation can distinguish the information entropy of EEG signals in three states well, and the threshold range is [0.1,3]. With the increase of threshold, the discrimination effect is gradually significant until stable, and the discrimination effect is obvious when the threshold is 0.5. The result of analysis indicated that EEG information entropy was the highest in the epileptic seizure period, followed by the epileptic seizure interval, and the lowest in normal human brain.

Loquat (Eriobotrya japonica Lindl.) leaves are often used as herbal or folk medicines and applied into modern pharmacology. In this study, the effect of three shading levels (control/non-shading, monolayer netting, bilayer netting) and the duration (0–88 days) on leaf gas exchange, leaf mineral nutrients, ursolic acid (UA) and oleanolic acid (OA) accumulation of loquat trees, Xinbai1, were assessed. The results indicated that UA and OA production improvement can be up to 17.20% and 9.35% respectively during bilayer netting treatments compared with control trees. Besides, a series of mixed-effect linear models with treatments and its duration as random effects revealed that the leaf transpiration within crown, Ca, P and K concentrations represented the most parsimonious combination for both UA and OA, consistent with the patterns in random forest regressions. Therefore, it emphasized that shading would be the potential cultural practices for high production of UA and OA through increasing foliar mineral nutrients.

Outlier detection is an important data mining technique to identify interesting and novel patterns, trends and anomalies from data. Density-based methods are among the most popular class of methods used in outlier detection. However, these methods suffer from the low density patterns problem that could lead to poor performance. In this paper, a novel relative density-based outlier detection algorithm is proposed, which utilizes a new measure of an object's neighborhood density. This approach takes into account an important factor for density: relative neighborhood. Experiments on both simulated and real data demonstrate that the proposed algorithm achieves better performance than other alternatives.

An important challenge for reaction-based fluorescent probes is that they generally require analyte consumption for fluorescence signal generation, thus creating potential perturbation of native analyte homeostasis or change of local concentrations. Herein, we reported two formaldehyde (FA) regeneration fluorescent probes, NAP-FAP-1 and NAP-FAP-2. An unprecedented regiospecific FA-induced intramolecularity strategy is implemented in the probe design, which adopts 3-(benzylamino)-succinimide as the FA-selective reaction group. The probes are able to capture the analyte molecule, induce regiospecific imide bond cleavage, and then release the captured FA molecule with simultaneous fluorescence turn-on response via a unique dual PeT/ICT quenching mechanism. The probes have shown potentials in detection, comparison, and imaging of FA levels intracellularly and inside lysosomes. These features make them useful for the study of FA homeostasis and functions in biological systems with minimal perturbation.

Vanadium titano-magnetite is a significant resource in China, and in this study, we characterize its isothermal reduction mechanisms in the mixture of H2, CO, and N2 where the variables considered here include reduction time, reduction temperature, gas composition, and pellet size. The kinetics of the reduction process are mainly studied, which follows a shrinking core model. The results indicate that the reduction degree of oxidized VTM pellets increases with the increase of reduction time, reduction temperature but decreases with the increase of pellet size. Moreover, we found that an increase of H2/(H2+CO) ratio induces an increase of the reduction degree. Then the transformation of main Ti-bearing mineral phases is discussed, and the most probable reaction mechanism is revealed. In the whole reduction process, the kinetic results confirm the existence of an early stage and a latter stage, which are controlled by interface chemical reaction and diffusion, respectively. Furthermore, the results show that the diffusion-control step can be observably shortened with the decrease of pellet size because a thinner product layer is formed during the reduction process. Our study thus provides a valuable technical basis on the VTM industrial application.

The presence of toxic elements in agricultural soils from anthropogenic activities is a potential threat to human health through the food chain. In this study, the concentration of toxic elements in 122 agricultural topsoil composite samples were determined in order to study the current status, identify their sources and assess the level of pollution and human health risk. The results showed that the mean concentrations of Zn, Cu, Pb, Cd, Hg and As in the farmland topsoil were 21.72, 15.09, 36.08, 0.2451, 0.0378 and 4.957 mg·kg−1, respectively. The spatial distribution showed that the soils were mainly contaminated by Cd, Pb and Hg in midwest Jilin but by Cu and As in the east. According to the pollution index (Pi), Nemerow integrated pollution index (PN) and Geo-Accumulation Index (Igeo), Cd and Pb were the main pollutants in the soils. The occurrence of these elements was caused by anthropogenic activities and they were concentrated in the Songyuan-Changchun-Siping economic belt. There is limited non-carcinogenic and carcinogenic health risk to humans. Principal component analyses suggest the Pb, Cd and Hg soil contamination was mainly derived from anthropogenic activities in the Midwest, but all examined toxic elements in the east were mainly due to geogenic anomalies and came from atmospheric deposition.

Purpose To determine the safety and efficacy of sorafenib combined with transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) (hereafter, S-TACE-RFA) in patients with medium or large (range, 3.1-7.0 cm in diameter) hepatocellular carcinoma (HCC). Materials and Methods This retrospective study evaluated the medical records of consecutive patients with medium or large HCC who underwent S-TACE-RFA or combined TACE and RFA (hereafter, TACE-RFA) from January 2010 to December 2014. Sorafenib was started 3-5 days after TACE, and RFA was performed 1-2 weeks after TACE. Treatment complications, recurrence-free survival (RFS), and overall survival (OS) in patients who underwent S-TACE-RFA were compared with those in patients who underwent TACE-RFA. Results Of the 174 patients who underwent S-TACE-RFA or TACE-RFA, 106 who met the eligibility criteria were included in this study. Among them, 40 underwent S-TACE-RFA and 66 underwent TACE-RFA. The patients who underwent S-TACE-RFA had longer RFS (median, 24.0 vs 10.0 months; P = .04) and better OS (median, 63.0 vs 36.0 months, P = .048) than those who underwent TACE-RFA. S-TACE-RFA and α-fetoprotein level were independent prognostic factors for survival in uni- and multivariable analyses. The rate of complications in patients who underwent S-TACE-RFA was similar to that in patients who underwent TACE-RFA (22.5% vs 18.2%, P = .59). Conclusion S-TACE-RFA resulted in longer RFS and better OS than did TACE-RFA in patients with medium or large HCC. © RSNA, 2018 Online supplemental material is available for this article.

As a convenient preparation technique, a two-step method, which is normally done by spin-coating CH

Biomechanics is a fundamental feature of a cell. The manner by which a mechanical feature could affect immune evasion of tumor cells remains an enigma. Here we show that although cytotoxic T lymphocytes (CTL) can effectively destroy stiff differentiated tumor cells, they fail to kill tumor-repopulating cells (TRC), whose softness effectively impedes the pore formation process through perforin released from CTLs. Mechanistically, perforin interacting with nonmuscle myosin heavy chain 9 transmits forces to fewer F-actins in soft TRCs, thus inducing a weak contractile force which is inadquate for pore formation by perforin. Stiffening soft TRCs confers perforin the drilling ability, leading to CTLs killing the TRCs, thus achieving a better tumor immunotherapeutic outcome. More importantly, overcoming the mechanical softness also enhances the killing of human TRCs by human CTLs. These findings provide mechanics-based immunotherapeutic strategies with potential clinical applications.

Autohydrolysis pretreatment with different severity factors was performed on poplar chips prior to chemi-thermomechanical pulping (CTMP) in order to investigate the change in pH value and its effect on the autohydrolysis pretreatment. The results showed that the dissolution amount of acetic acid increased with raising the severity factor of the pretreatment and declining the size of poplar chips, respectively. Besides, a logarithmic relationship between the amount of acetic acid released in the autohydrolysis liquor (AHL) and pH value of the AHL was observed. The amounts of glucose and xylose (including those in the form of monomers, oligomers, and polysaccharides) as well as furfural and hydroxymethylfurfural (HMF) also depended on the pH value of the AHL to some extent.

Sucrose and its cleavage products are essential molecules in higher plants. Vacuolar invertase (VIN) is a type of invertase that is specifically localised in the vacuole. It irreversibly cleaves sucrose into glucose and fructose, and plays important roles in sugar accumulation or cell expansion. In this study, a full-length cDNA of the VIN gene, EjVIN, was isolated from loquat (Eriobotrya japonica Lindl.). The EjVIN encoding protein possesses typical and highly conserved motifs among plant VINs, including the β-fructosidase motif (NDPNG), catalytic domain (WECVD) and a possible vacuolar targeting motif (ILPN). Phylogenic analyses showed that EjVIN is close to apple and pear VIN, falling within the VIN subgroup. EjVIN transcript and acid invertase activity were highest in the early stages of fruit development and in mature fruit. The transcript of EjVIN was significantly enhanced in vivo after 3 h of treatment with fructose or glucose. The transgenic tobacco plants overexpressed EjVIN grew faster with decreased size. Further analyses indicate that the sucrose levels were decreased, but fructose levels were slightly increased in immature transgenic plants compared with wild type plants. The results indicate that EjVIN play more important role during early loquat fruit development stage. Overexpression of loquat EjVIN accelerated sucrose hydrolysis, affected plant growth, which possibly due to a modification of the metabolic fluxes in the transgenic plants at early development stage.

To study the structural characteristics and physical properties of droplets sitting on the inclined substrates and cylindrical surfaces, wetting experiments are conducted in different cases. The profile curves of the droplets are recorded and extracted by a CCD camera and image processing, respectively. Contact angles are figured out by fitting the profile curves and taking the derivative at the front and rear triple points. Based on the experimental results, a Surface Evolver is employed to simulate the morphological changes by minimizing the total energy of the system. Furthermore, theoretical shapes and feature parameters, including the heights and the spreading distances of the droplets, which are hard to obtain by normal experimental measurements are provided. The contact-angle hysteresis when the heavy droplet sitting on the inclined substrate is discussed. Meanwhile, the evolutions of the contour of the three-phase contact line are predicted when heavy droplets spread on the convex and concave cyli...

CH3NH3PbBr3-based bulk perovskite solar cells with core/shell nanoarray as electron transporter are fabricated for the first time, and an efficiency of 4.31% under AM 1.5 illumination (100 mW/cm2) was achieved. It is found that the open-circuit voltage in the CH3NH3PbBr3/nanoarray devices is determined by the difference between the conduction band of ZnO core and the highest occupied molecular orbital of CH3NH3PbBr3, but significantly correlates with the quasi-Fermi levels of the electrons in ZnO and the holes in CH3NH3PbBr3; thermal annealing is an effective way to enhance the device short-circuit current density by increasing charge generation and reducing interfacial charge recombination. In the CH3NH3PbBr3/nanoarray devices, interfacial characteristics are vitally important to the device performance, which is mainly embodied by the existing CdS shell that provides additional absorption contribution, passivates ZnO surface defects, reduces interfacial charge recombination, and eliminates the decomposition of CH3NH3PbBr3 on ZnO surface during the thermal annealing treatment for improving perovskite crystallinity to increase photocurrent. Our major findings are expected to provide a guide to design the effective interfaces for spatial separation of photogenerated charge carriers in efficient perovskite solar cells.

To develop solution-processed and novel device structures is of great importance for achieving advanced and low-cost solar cells. In this paper, we report the solution-processed solar cells based on inorganic bulk heterojunctions (BHJs) featuring a bulk crystalline Sb2S3 absorbing layer interdigitated with a TiO2 nanoarray as an electron transporter. A solution-processed amorphous-to-crystalline transformation strategy is used for the preparation of Sb2S3/TiO2-BHJs. Steady-state and dynamic results demonstrate that the crystalline structure in the Sb2S3 absorbing layer is crucial for efficient devices, and a better Sb2S3 crystallization favors a higher device performance by increasing the charge collection efficiency for a higher short-circuit current, due to reduced interfacial and bulk charge recombinations, and enhancing the open-circuit voltage and fill factor with the reduced defect states in the Sb2S3 layer as well. Moreover, an evident contribution to photocurrent generation from the photogenerated holes in the Sb2S3 layer is revealed by experimental and simulated dynamic data. These results imply a kind of potential non-excitonic BHJ for energy conversion.

High-purity Cu2ZnSnS4 quantum dots (CZTS-QDs) with a size of 3–5 nm and a band gap of 1.67 eV are synthesized by a facile solvothermal method using simple chemicals in ethanol solvent. The CZTS-QDs have an ionization potential (IP) of −5.96 eV and an electron affinity (EA) of −4.33 eV, which are almost not changed after removal of capping molecules on them. Due to the favorable IP and EA positions with respect to those of poly(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene) (MEH-PPV), the CZTS-QDs act as effective electron acceptors for hybrid solar cells based on polymer/CZTS blends with MEH-PPV as the polymer. CZTS-QDs and MEH-PPV form type-II heterojunctions to enable the solar cells to have a promising open-circuit voltage of 0.63 V, and the efficient charge separation for neutral excited states produced either on the polymer or on the CZTS-QDs makes the solar cells have a wide spectral response extending to 900 nm. It is revealed that removal of capping molecules on the quantum dots mainly leads to a reduced polymer exciton diffusion effect on the electron transport dynamics due to the formation of wider CZTS charge transport channels and an increased short-circuit current (Jsc) in the solar cells, where the enhanced Jsc dominantly correlates with the increased charge transfer and collection efficiencies due to the improved charge transport property in CZTS channels.

Investigating the behaviors of impurities such as carbon, nitrogen and oxygen within tungsten is crucial to understanding the formation of compounds which can substantially influence the physical and chemical properties of tungsten. Using density functional theory method, we have investigated the geometry and energetics of small VacXn, SolXn and SolVacXn (Vac = vacancy, Sol = solute, and X = C, N or O) clusters to probe the aggregation of X in tungsten. We find that vacancy and solute–vacancies show great attraction to X atoms and multiple X atoms can be embedded in the defects. Four C atoms segregate in a vacancy forming a square where the C–C bond forms with the bond length of 1.58 A, however, it is hard to form N–N (or O–O) bonds in a vacancy although up to six N (or O) atoms can be trapped in a vacancy. The solutes titanium, tantalum, rhenium and osmium present relatively weak attraction to X atoms, and the binding energies of the solute with X rely on the bond length of Sol-X. Moreover, the concentration evolution of VacCn (SolCn) is determined through the law of mass action, and the results show that the concentrations of VacCn (SolCn) depend strongly on temperature, and the initial concentrations of vacancy (Sol) and C. The binding energy of SolVacXn correlates linearly with the volume difference of the system containing a SolVacXn and that with no defects. The aggregation of X atoms in the microstructure of tungsten, forming high X concentration zones, may facilitate the formation of compounds.

Three different pre-extraction methods (i.e., acetic acid, sulfuric acid and sodium hydroxide) were used for the pretreatment followed by chemi-thermomechanical treatments and then enzymatic hydrolysis of wheat straw to produce fermentable sugars. The performance of enzymatic hydrolysis by the synergistic effect of pre-extractions and chemi-thermomechanical treatments was remarkable. Results showed that the pre-extraction combining with the chemi-thermomechanical treatments shorten the enzymatic hydrolysis time and improved the glucose yield at the same enzyme loadings. The chemical components, swelling ability, and crystallinity, as well as the surface morphology of the substrates were changed obviously. All of these changes can affect the accessibility of enzymes to cellulose in the substrates to a certain extent.

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with different variety of clinical manifestations. Natural killer T (NKT) cells are innate lymphocytes that play a regulatory role during broad range of immune responses. A number of studies demonstrated that the quantity and quality of invariant NKT (iNKT) cells showed marked defects in SLE patients in comparison to healthy controls. This finding suggests that iNKT cells may play a regulatory role in the occurrence and development of this disease. In this review, we mainly summarized the most recent findings about the behavior of NKT cells in SLE patients and mouse models, as well as how NKT cells affect the proportion of T helper cells and the production of autoreactive antibodies in the progress of SLE. This will help people better understand the role of NKT cells in the development of SLE and improve the therapy strategy.

The purpose of this study was to introduce a modified transjugular intrahepatic portosystemic shunt (TIPS), a percutaneous transhepatic intrahepatic portosystemic shunt (PTIPS), and to evaluate its feasibility and efficacy in patients with variceal bleeding with chronic portal vein occlusion (CPVO) after splenectomy. Twenty-four cirrhotic patients with CPVO after splenectomy who received PTIPS between 2010 and 2015 were included in this retrospective study. The indication was elective control of variceal bleeding. Success rates, effectiveness and complications were evaluated, with comparison of the pre- and post-portosystemic pressure gradient (PPG). Patients’ clinical outcomes and shunt patency were followed periodically. PTIPS was successfully placed in 22 patients (91.7%) and failed in two. The mean PPG fell from 22.0 ± 4.9 mmHg to 10.6 ± 1.6 mmHg after successful PTIPS (p < 0.05). No fatal procedural complications occurred. During the median follow-up of 29 months, shunt dysfunction occurred in five cases and hepatic encephalopathy in four cases. Three patients died because of rebleeding, hepatic failure and pulmonary disease, respectively. The other patients remained asymptomatic and the shunts patent. We conclude that PTIPS, as a modified TIPS procedure with a high success rate, is safe and effective for variceal bleeding with CPVO after splenectomy. • Portal vein occlusion used to be contraindication to transjugular intrahepatic portosystemic shunt. • Portal vein thrombosis is common in patients with previous splenectomy. • We developed a new method, percutaneous transhepatic intrahepatic portosystemic shunt (PTIPS). • PTIPS is feasible in patients with portal vein thrombosis and splenectomy. • PTIPS is effective and safe for these kind of complicated portal hypertension.

Developing novel drugs that can abrogate the growth and metastasis of malignant tumors is a major challenge for cancer researchers. Here we describe a novel synthetic retinoid, namely WYC-209, which inhibits proliferation of malignant murine melanoma tumor-repopulating cells (TRCs), known to resist conventional drug treatment, with an IC50 of 0.19 μM in a dose-dependent manner. WYC-209 also inhibits proliferation of TRCs of human melanoma, lung cancer, ovarian cancer, and breast cancer in culture. Interestingly, the treated TRCs fail to resume growth even after the drug washout. Importantly, the molecule abrogates 87.5% of lung metastases of melanoma TRCs in immune-competent wild-type C57BL/6 mice at 0.22 mg kg−1 without showing apparent toxicity. Pretreating the melanoma TRCs with retinoic acid receptor (RAR) antagonists or with RAR siRNAs blocks or reduces the inhibitory effect of the molecule, suggesting that the target of the molecule is RAR. WYC-209 induces TRC apoptosis and pretreating the TRCs with caspase 3 inhibitor or depleting caspase 3 with siRNAs substantially rescues growth of TRCs from WYC-209 inhibition, suggesting that WYC-209 induces TRCs apoptosis primarily via the caspase 3 pathway. Our findings demonstrate the promise of the new retinoid WYC-209 in treating malignant melanoma tumors with high efficacy and little toxicity., The discovery of efficient drugs is a main challenge in cancer therapy. Here, the authors report a synthetic retinoid, WYC-209 with anti-tumor and anti-metastatic activity mediated by the retinoic acid receptor signaling pathway.

Cells and tissues can undergo a variety of biological and structural changes in response to mechanical forces. Only few existing techniques are available for quantification of structural changes at high resolution in response to forces applied along different directions. Three dimensional-Magnetic Twisting Cytometry (3D-MTC) is a technique for applying local mechanical stresses on living cells. Here we describe a protocol for interfacing 3D-MTC with confocal fluorescence microscopy. In 3D-MTC, ferromagnetic beads are bound to the cell surface via surface receptors followed by their magnetization in any desired direction. A magnetic twisting field in a different direction is then applied to generate rotational shear stresses in any desired direction. This protocol describes how to combine magnetic field-induced mechanical stimulation with confocal fluorescence microscopy and provides an optional extension for super resolution imaging using stimulated emission depletion (STED) nanoscopy. This technology allows for rapid real time acquisition of a living cell’s mechanical responses to forces via specific receptors and for quantifying structural and biochemical changes in the same cell using confocal fluorescence microscopy or STED. The integrated 3D-MTC – microscopy platform takes around 20 days to construct and the experimental procedures require ~4 days when carried out by a life sciences graduate student.

We perform first-principles calculations to investigate the interaction of H with He in W and Mo. One vacancy with one He atom located at the vacancy center (Vac-He 1 ) could trap up to 12 H atoms, forming a Vac-He 1 –H 12 complex in W and Mo. There is no H 2 molecule formed in the Vac-He 1 –H n ( n ranges from 1 to 12) complex. The calculations of the formation energy of Vac-He 1 –H n complexes indicate that Vac-He 1 –H 4 is the most energetically favorable. The formation energy of Vac-He 1 –H n is larger than that of Vac-H n by up to 0.6 eV in both W and Mo. Vac-He m ( m > 1) complex could also trap H atom, and the binding energy of Vac-He m with one closest H atom does not increase with the He atom number m . On the basis of the obtained energetics of Vac-He m complexes, a cascade mechanism is shown that once a Vac-He 1 complex traps enough H atoms, neighboring W or Mo atoms will become weakly bound thus easily removed.

Bare nonprecious metal oxides are generally considered to have low HER activity, but they have the advantages of abundant resources and low cost. Herein, a facile strategy to construct abundant oxygen vacancies with heterogeneous structures of oxygen-vacancies CoFe2O4/oxygen-vacancies cobalt oxides/nickel foam (Ov-CoFe2O4/CoOx/NF) is developed using gas-phase cation exchange. Benefiting from abundant oxygen vacancies, the strong interfacial coupling effects between oxygen-vacancies CoFe2O4 (Ov-CoFe2O4) and oxygen-vacancies cobalt oxides (Ov-CoOx), a nanorod structure and the highly conductive nickel foam support, Ov-CoFe2O4/CoOx/NF exhibits a low overpotential of 59 mV and achieved a current density of 10 mA cm−2 in a 1 M KOH solution. Ov-CoFe2O4/CoOx/NF//Ov-CoFe2O4/CoOx/NF exhibits a low water splitting voltage of 1.51 V at 10 mA cm−2. Density functional theory calculations suggest that oxygen vacancy and interfacial coupling effects can both improve conductivity of electrocatalysts. This study provides a facile design for simultaneous realization of oxygen vacancy modification and heterostructure, which may become a simple strategy to use oxides to improve HER performance.

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disorder mainly mediated by lymphocytes and autoantibodies, which have a pervasive negative impact on the majority of organs.1 2 It deserves more attention to further explore the pathogenesis because of the unclear complex pathogenesis and the limited clinical efficacy of SLE treatment. Recently, a cross-sectional discovery cohort in the USA conducted by Azzouz et al , published in Annals of Rheumatic Diseases, suggested that specific gut commensal strains, especially Ruminococcus gnavus , may contribute to the disease activity and autoantibody production in SLE patients,3 which put forward a novel concept for the immune pathogenesis of SLE. Their study was well performed and analysed the abundance of intestinal flora and sera profiled for antibacterial and autoantibody responses between SLE patients with the different disease activity index scores and matched healthy controls. However, the faecal microbiota is lacking a precise link with lymphocytes in peripheral blood of the patients, which are the important participants …

The attainment of long-pulse, high-performance, fully non-inductive plasma is one of the major scientific objectives of EAST, using the ITER-like tungsten upper divertor. Understanding and optimizing the fast-ion behaviors is the critical issue to extending the performance of EAST. Recently, using both neutral beam injection (NBI) and radio frequency (RF; low hybrid, electron cyclotron, and ion cyclotron) heating, fully non-inductive high-βP scenarios with extension of fusion performance at high density and low rotation have been achieved, with βP up to 2.5, βN up to 2.0, H98y 2 > 1.1, and bootstrap current fraction (f BS) up to 50%. For previous long-pulse H-mode plasma at medium density, when NBI is added into RF plasma, βP is increased from 1.2 to 2.0 compared with RF-only discharges. In fact, f BS for both discharges is nearly the same, at ~22%. Analysis shows that the increase in βp is mostly due to fast ions which do not contribute significantly to the neoclassical bootstrap current. Thus, to obtain high-performance plasmas with improved bootstrap current fraction, key parameters (e.g. density, beam energy, etc.) must be further optimized. Experimental results show that high density improves bootstrap fraction also by reducing fast-ion slowing-down time and loss. The lower beam energy also mitigates fast-ion loss, which is better for heating and CD performance. The extension of high-performance, fully non-inductive experiments on EAST at high density and zero/low NBI torque can potentially offer unique contributions towards ITER and CFETR.

A bulk charge exchange spectroscopy system has been applied to measure the radial profiles of the hydrogen (H) and deuterium (D) density ratio in the isotope mixture plasma in a large helical device. Charge exchange lines of Hα and Dα are fitted by 4 Gaussian of H and D cold components and H and D hot components with 5 parameters by combining the measurement of plasma toroidal rotation velocity with carbon charge exchange spectroscopy. The radial profiles of the relative density of hydrogen and deuterium ions are derived from H and D hot components measured and the beam density calculated from beam attenuation calculation. A proof-of-principle experiment is performed by the H pellet and the D pellet injections into the H-D mixture plasma.

An asymmetric parallel return flow, which modifies the parallel component of the flow, is expected to meet the zero divergence of the flow on a flux surface based on the common neoclassical theory for torus plasma. The full flow structure is measured by charge exchange spectroscopy on the Large Helical Device. Inboard/outboard asymmetry of the parallel flow is observed according to the full flow profile measurement. Flow asymmetry is considered to be induced by the Pfirsch–Schlüter flow closely associated with the radial electric field. A linear relationship between the integrated flow asymmetry and the electric potential difference is obtained in different magnetic fields and configurations. A model based upon the incompressibility of the flow is applied to acquire a geometric factor hB, which only connects to the magnetic configuration from the experiment. The asymmetric component of the parallel flow measured is compared with the asymmetric component of parallel flow calculated in the incompressibility conditions of flow on the magnetic flux surface. The measured asymmetric flow is consistent with the calculation in plasma with a small toroidal torque input in the inward shifted configuration. However, the measured asymmetric flow is significantly smaller than that calculated for plasma with a large toroidal torque or in the outward shifted configuration. One possible explanation for this variation could be radial transport due to anomalous perpendicular viscosity as well as strongly poloidally asymmetric radial flow.

Recent Experimental Advanced Superconducting Tokamak (EAST) experiments have successfully demonstrated a long-pulse steady-state scenario with improved plasma performance through integrated operation since the last IAEA FEC in 2016. A discharge with a duration over 100 s using pure radio frequency (RF) power heating and current drive has been obtained with the required characteristics for future long-pulse tokamak reactors such as good energy confinement quality (H98y2 ~ 1.1) with electron internal transport barrier inside ρ < 0.4, small ELMs (frequency ~100–200 Hz), and good control of impurity and heat exhaust with the tungsten divertor. The optimization of X-point, plasma shape, the outer gap and local gas puffing near the low hybrid wave (LHW) antenna were integrated with global parameters of B T and line-averaged electron density for higher current drive efficiency of LHW and on-axis deposition of electron cyclotron heating in the long-pulse operation. More recently, a high β P RF-only discharge (β P ~ 1.9 and β N ~ 1.5, /n GW ~ 0.80, f bs ~ 45% at q 95 ~ 6.8) was successfully maintained over 24 s with improved hardware capabilities, demonstrating performance levels needed for the China Fusion Engineering Test Reactor steady-state operation. A higher energy confinement is observed at higher β P and with favorable toroidal field direction. Towards the next goal (≥400 s long-pulse H-mode operations with ~50% bootstrap current fraction) on EAST, an integrated control of the current density profile, pressure profile and radiated divertor will be addressed in the near future.

Armored equipment plays a crucial role in the ground battlefield. The fast and accurate detection of enemy armored targets is significant to take the initiative in the battlefield. Comparing to general object detection and vehicle detection, armored target detection in battlefield environment is more challenging due to the long distance of observation and the complicated environment. In this paper, an accurate and robust automatic detection method is proposed to detect armored targets in battlefield environment. Firstly, inspired by Feature Pyramid Network (FPN), we propose a top-down aggregation (TDA) network which enhances shallow feature maps by aggregating semantic information from deeper layers. Then, using the proposed TDA network in a basic Faster R-CNN framework, we explore the further optimization of the approach for armored target detection: for the Region of Interest (RoI) Proposal Network (RPN), we propose a multi-branch RPNs framework to generate proposals that match the scale of armored targets and the specific receptive field of each aggregated layer and design hierarchical loss for the multi-branch RPNs; for RoI Classifier Network (RCN), we apply RoI pooling on the single finest scale feature map and construct a light and fast detection network. To evaluate our method, comparable experiments with state-of-art detection methods were conducted on a challenging dataset of images with armored targets. The experimental results demonstrate the effectiveness of the proposed method in terms of detection accuracy and recall rate.

Tumor-repopulating cells are a tumorigenic sub-population of cancer cells that drives tumorigenesis. We have recently reported that soft fibrin matrices maintain tumor-repopulating cell growth by promoting histone 3 lysine 9 (H3K9) demethylation and Sox2 expression and that Cdc42 expression influences H3K9 methylation. However, the underlying mechanisms of how soft matrices induce H3K9 demethylation remain elusive. Here we find that tumor-repopulating cells exhibit lower focal adhesion kinase (FAK) and H3K9 methylation levels in soft fibrin matrices than control melanoma cells on 2D rigid substrates. Silencing FAK in control melanoma cells decreases H3K9 methylation, whereas overexpressing FAK in tumor-repopulating cells enhances H3K9 methylation. Overexpressing Cdc42 or RhoA in the presence of FAK knockdown restores H3K9 methylation levels. Importantly, silencing FAK, Cdc42, or RhoA promotes Sox2 expression and proliferation of control melanoma cells in stiff fibrin matrices, whereas overexpressing each gene suppresses Sox2 expression and reduces growth of TRCs in soft but not in stiff fibrin matrices. Our findings suggest that low FAK mediated by soft fibrin matrices downregulates H3K9 methylation through reduction of Cdc42 and RhoA and promotes growth of tumor-repopulating cells.

Cancer metastasis is the most deadly stage in cancer progression. Despite significant efforts over the past decades, it remains elusive why only a very small fraction of cancer cells is able to generate micrometastasis and metastatic colonization. Recently we have shown that tumor-repopulating cells (TRCs), a highly tumorigenic subpopulation of mouse melanoma cells, can be selected by being cultured and grown in 3D soft fibrin gels. Here we show that when injected into the yolk of a 2 day-post-fertilization (dpf) embryo of Tg (fli1:EGFP or kdrl:mCherry) zebrafish, TRCs are much more efficient in surviving and growing at various secondary sites to generate micrometastasis and metastatic colonization than control melanoma cells that are grown on rigid plastic. The metastasis of TRCs is dependent on the presence of Sox2, a self-renewal gene and silencing Sox2 leads to the inhibition of TRC metastasis. High-resolution of 3D confocal images of the TRCs at the secondary sites show that extravasation and formation of micrometastases by TRCs are more efficient than by the control cells. Remarkably, efficient extravasation of TRCs in vivo and transmigration in vitro are determined by TRC deformability, as a result of low Cdc42 and high Sox2. Our findings suggest that tumor cell deformability is a key factor in controlling extravasation dynamics during metastasis.

The identification of stem-cell-like cancer cells through conventional methods that depend on stem cell markers is often unreliable. We developed a mechanical method for selecting tumorigenic cells by culturing single cancer cells in fibrin matrices of ~100 Pa in stiffness. When cultured within these gels, primary human cancer cells or single cancer cells from mouse or human cancer cell lines grew within a few days into individual round colonies that resembled embryonic stem cell colonies. Subcutaneous or intravenous injection of 10 or 100 fibrin-cultured cells in syngeneic or severe combined immunodeficiency mice led to the formation of solid tumours at the site of injection or at the distant lung organ much more efficiently than control cancer cells selected using conventional surface marker methods or cultured on conventional rigid dishes or on soft gels. Remarkably, as few as ten such cells were able to survive and form tumours in the lungs of wild-type non-syngeneic mice.