The impact of impurity ions on a pedestal has been investigated in the HL-2A Tokamak, at the Southwestern Institute of Physics, Chengdu, China. Experimental results have clearly shown that during the ...H-mode phase, an electromagnetic turbulence was excited in the edge plasma region, where the impurity ions exhibited a peaked profile. It has been found that double impurity critical gradients are responsible for triggering the turbulence. Strong stiffness of the impurity profile has been observed during cyclic transitions between the I-phase and H-mode regime. The results suggest that the underlying physics of the self-regulated edge impurity profile offers the possibility for an active control of the pedestal dynamics via pedestal turbulence.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Abstract This paper studied through-thickness gradient microstructure of an 80mm ultra-heavy steel plate by multi-dimensional characterizations, meanwhile the cause of microstructure variability as ...well as its effect on strength was analyzed. Results show major lath-structure in the whole steel plate, while lath morphology and grain boundary distribution are different along the thickness direction. During phase transformation, the higher cooling rate in the surface enhances the forming ability of V1/V4 variant pairs and corresponding 5°-10° boundaries, meanwhile the higher cooling rate and smaller original austenite grain contribute to more nucleation sites and stronger strain incompatibility, which is corresponding to more low-angle boundaries, so the surface layer shows higher low-angle boundaries; Compared with the surface layer, the moderate cooling rate is beneficial for V1/V2 variant pairs, and Σ3 boundaries between the pairs are obtained, leading to higher high-angle boundary density with decreased low-angle grain boundary density. This boundary characteristic corresponds to the thinner and longer lath morphology. With respect to the relationship between mechanical properties and microstructure, more low-angle boundaries in the surface layer and more high-angle boundaries in inner layers contribute to stronger dislocation strengthening and grain boundary strengthening respectively, and realizes the coordinated through-thickness property.
•A two-dimensional model for the design of flow fields in VRFBs is reported.•Uniformity of vanadium ion distribution is evaluated by uniformity factors.•Pressure drop is accurately captured in ...interdigitated and serpentine flow fields.•Performance of several design of flow fields for a large cell is studied.
In this work, we report a two-dimensional mathematical model for the design of flow fields in vanadium redox flow batteries (VRFBs). The model is validated by calculating the pressure drop, distribution uniformity of vanadium ions in an interdigitated flow field and a serpentine flow field for a 9-cm2 cell. The model is then used to simulate interdigitated and a series of parallel serpentine design of flow fields in a 410-cm2 cell. It is demonstrated that with an increase in the number of parallel serpentine channels, the pumping power decreases while the distribution of vanadium ions becomes less uniform. Among the design of flow fields studied in this work, the interdigitated design performs the lowest pumping power and the most uniform distributions of vanadium ions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Aim
Perineal wound complications after abdominoperineal resection (APR) have become a major clinical challenge. Myocutaneous flap closure has been proposed in place of primary closure to improve ...wound healing. We conducted this comprehensive meta‐analysis to evaluate the current scientific evidence of primary closure vs myocutaneous flap closure of perineal defects following APR for colorectal disease.
Methods
We systematically searched the MEDLINE, Embase, PubMed, Web of Science and Cochrane Library databases to identify all relevant studies. After data extraction from the included studies, meta‐analysis was performed to compare perioperative outcomes of primary closure and myocutaneous flap closure.
Results
Eighteen studies with a total of 17 913 patients (16 346 primary closure vs 1567 myocutaneous flap closure) were included. We found that primary closure was significantly associated with higher total perineal wound complications (P = 0.007), major perineal wound complications (P < 0.001) and perineal wound infection (P = 0.001). On the other hand, myocutaneous flap closure takes more operation time (P < 0.001) and increases the risk of perineal wound dehiscence (P = 0.01), deep surgical site infection (P < 0.001), enterocutaneous fistulas (P = 0.03) and return to the operating room (P = 0.0005). There were no significant differences between the two groups for other outcomes.
Conclusions
This is the first systematic review with meta‐analysis comparing primary closure with myocutaneous flap closure of perineal defects after APR for colorectal disease. Although taking more operation time and an increased risk of specific complications, the pooled results have validated the use of myocutaneous flaps for reducing total/major perineal wound complications. More investigations are needed to draw definitive conclusions on this dilemma.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Proteomic analysis of exosomes from human plasma faces a tremendous challenge mainly due to the low abundance of the exosome itself and the complexity of the plasma matrix. Therefore, enrichment of ...exosomes from human plasma is an essential and indispensable step for large scale and in depth proteomic analysis. Size exclusion chromatography (SEC) is one of the most extensively used methods for exosome isolation from human plasma and many SEC-based tandem methods were established in order to increase the purity of the enriched exosomes and thus the accuracy of the proteomic analysis. To compare the advantages and disadvantages of the different isolation methods and subsequently to promote the establishment of a standardized method for plasma proteomic research, the capacities of the direct SEC method, the combination of SEC with ultracentrifugation (SEC-UC), ultrafiltration (SEC-UF), and titanium dioxide microspheres (SEC-TiO
2
) were systematically evaluated for exosome isolation from human plasma and thus proteomic analysis. The results demonstrated that the SEC-based tandem methods were superior to the direct SEC method in the purity of exosomes isolated from human plasma. Additionally, the SEC-UC method possessed the highest number of the total identified proteins and the overlapped proteins with the top 100 exosome markers in comparison with the other methods. The SEC-TiO
2
method displayed the biggest capacity for plasma protein deleting. We expect that the research will have more beneficial values in the field of exosome research.
The capacities of four different size exclusion chromatography (SEC)-based methods were evaluated for the purpose of establishing a "gold standard method" for isolation of exosomes from human plasma and thus accurate proteomic analysis.
The aim of this study was to investigate whether microRNA-150-5p was involved in osteosarcoma cell proliferation and invasiveness via modulating vascular endothelial growth factor A (VEGFA) ...expression.
10 pairs of osteosarcoma tissues and para-cancerous tissues were collected from patients with osteosarcoma in our center from February 2012 to July 2018. Relative expression levels of microRNA-150-5p and VEGFA in tissues and cell lines were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Luciferase reporter gene assay was conducted to illustrate the binding interplay between microRNA-150-5p and VEGFA. Furthermore, proliferative and invasive potentials in HOS and MG-63 cells regulated by both microRNA-150-5p and VEGFA were determined using Cell Counting Kit-8 (CCK-8), colony formation assay, and transwell assay, respectively.
MicroRNA-150-5p was remarkably downregulated, while VEGFA was upregulated in osteosarcoma tissues compared with para-cancerous tissues (p<0.05). Similar results were observed in osteosarcoma cells and normal osteoblasts. Overexpression of microRNA-150-5p significantly inhibited the proliferation and invasion of osteosarcoma cells (p<0.05). Luciferase reporter gene assay demonstrated that microRNA-150-5p could target to VEGFA to negatively modulate its expression. In addition, the knockdown of VEGFA remarkably weakened osteosarcoma cell proliferative and invasive capacities (p<0.05).
MicroRNA-150-5p weakens proliferative and invasive potentials in osteosarcoma cells by downregulating VEGFA level. All our findings suggest that microRNA-150-5p/VEGFA axis is a promising target for osteosarcoma treatment.
Although body mass index (BMI) and waist circumference (WC) are correlated, the relationship between WC and BMI may have changed over time.
To describe temporal trends in BMI and WC distributions and ...quantify the increase in WC at a given BMI over time.
Data on adults aged 20-59 years from two waves (1993 and 2009) of the China Health and Nutrition Survey were used in a pooled cross-sectional analysis. Quantile regression examined age-adjusted temporal trends in the distributions of BMI and WC. Linear regression examined changes in mean WC over time, adjusting for BMI, age at survey and survey year. All models were stratified by gender.
There was a significant increase in BMI and WC over time, particularly at the 95th quantile: on average, men had 2.8 kg m(-2) (95% confidence interval (CI): 2.4, 3.3) and women 1.5 kg m(-)(2) (95% CI: 1.1, 2.0) higher BMI in 2009 compared with their counterparts in 1993. WC increased by 9.0 cm (95% CI: 7.5, 10.1) and 5.0 cm (95% CI: 3.4, 6.6) for men and women, respectively. On average, men and women had a 3.2 cm (95% CI: 2.8, 3.7) and 2.1 cm (95% CI: 1.7, 2.5) higher WC in 2009 compared with their counterparts in 1993, holding BMI and age constant. WC adjusted for BMI increased to a larger extent among obese versus lean individuals and among younger versus older women.
For both genders, BMI and WC increased significantly over time, with particularly greatest increase in magnitude in the upper tail of the BMI and WC distributions. Furthermore, WC at equivalent BMIs was higher in 2009, compared with their counterparts in 1993. Our findings suggest that even if BMI remained constant from 1993 to 2009, adults in 2009 might be at increased cardiometabolic risk as a result of their higher WC.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
ABSTRACT II UMa is a late F-type (F5) contact binary with a close-in tertiary and a distant visual companion. According to the four-color (B V RcIc) light curves' solutions of II UMa, it is a high ...fill-out (f = ) and low-mass ratio (q = 0.172) contact binary system, which indicates that it is at the late evolutionary stage of late-type tidal-locked binary stars. The masses of the primary star and secondary star are calculated to be and . The primary star has evolved from the zero-age main sequence, but it still appeared before the terminal-age main sequence, and the secondary star is even more evolved. Considering the mass ratio ( ) obtained by spectroscopic observations, the mass of the close-in tertiary is estimated to be . The period variations of the binary system are investigated for the first time. According to the observed-calculated (O−C) curve analysis, a continuous period increase at a rate of is determined. The parabolic variation in the O−C curve may be part of a cyclic period of change, or the combined period of change of a parabolic variation and a cyclic one. More instances of minimum light are needed to confirm this. The presence of the tertiary component may play an important role in the formation and evolution of this binary system by drawing angular momentum from the central system during the pre-contact stage.
The multifluid Lyon‐Fedder‐Mobarry (MFLFM) global magnetosphere model is used to study the interactions between solar wind and rapidly rotating, internally driven Jupiter magnetosphere. The MFLFM ...model is the first global simulation of Jupiter magnetosphere that captures the Kelvin‐Helmholtz instability (KHI) in the critically important subsolar region. Observations indicate that Kelvin‐Helmholtz vortices are found predominantly in the dusk sector. Our simulations explain that this distribution is driven by the growth of KHI modes in the prenoon and subsolar region (e.g., >10 local time) that are advected by magnetospheric flows to the dusk sector. The period of density fluctuations at the dusk terminator flank (18 magnetic local time, MLT) is roughly 1.4 h compared with 7.2 h at the dawn flank (6 MLT). Although the simulations are only performed using parameters of the Jupiter's magnetosphere, the results may also have implications for solar wind‐magnetosphere interactions at other corotation‐dominated systems such as Saturn. For instance, the simulated average azimuthal speed of magnetosheath flows exhibit significant dawn‐dusk asymmetry, consistent with recent observations at Saturn. The results are particularly relevant for the ongoing Juno mission and the analysis of dawnside magnetopause boundary crossings for other planetary missions.
Key Points
KHI in the subsolar region is critically important for boundary layer dynamics in Jupiter's magnetosphere
Simulations show that duskward moving KH waves originate at around 10 MLT, and stationary KH waves form on the dawnside around 08‐09 MLT
Duskside density fluctuations associated with KHI exhibit much longer periodicity compared to those on the dawnside
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abstract
Interactions between a T cell receptor (TCR) and a peptide-major histocompatibility complex (pMHC) ligand are typically mediated by noncovalent bonds. By studying T cells expressing natural ...or engineered TCRs, here we describe covalent TCR-pMHC interactions that involve a cysteine-cysteine disulfide bond between the TCR and the peptide. By introducing cysteines into a known TCR-pMHC combination, we demonstrate that disulfide bond formation does not require structural rearrangement of the TCR or the peptide. We further show these disulfide bonds still form even when the initial affinity of the TCR-pMHC interaction is low. Accordingly, TCR-peptide disulfide bonds facilitate T cell activation by pMHC ligands with a wide spectrum of affinities for the TCR. Physiologically, this mechanism induces strong Zap70-dependent TCR signaling, which triggers T cell deletion or agonist selection in the thymus cortex. Covalent TCR-pMHC interactions may thus underlie a physiological T cell activation mechanism that has applications in basic immunology and potentially in immunotherapy.
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