Heat Transfer Analysis of MgB₂ Coil in Heat Treatment Process for Future Fusion Reactor

State of the art MgB2 is reviewed as a potential material for the poloidal field (PF) coils of the future fusion reactor due to its high critical temperature and low material cost. The heat treatment process is a crucial step in the development of MgB2 magnets. The temperature lag in heat treatment of large magnets can lead to insufficient thermal reaction time. It may be infeasible to control the temperature of a magnet according to the heat treatment scheme recommended for the MgB2 wire. Hence, the heat treatment process of a large magnet needs to be evaluated. Therefore, the dynamic temperature distribution of a MgB2 PF coil is obtained by simulating the heat transfer in heat treatment process. A suitable heat treatment schedule for a large magnet is proposed and the experimental results of a sub-size Cable-In-Conduit Conductor manufactured with MgB2 strand confirmed the feasibility of the newly proposed heat treatment process. The results provide a reference for the heat treatment method of a future larger MgB2 coil.</p

MicroRNA Let-7a Inhibits Proliferation of Human Prostate Cancer Cells In Vitro and In Vivo by Targeting E2F2 and CCND2

Previous work has shown reduced expression levels of let-7 in lung tumors. But little is known about the expression or mechanisms of let-7a in prostate cancer. In this study, we used in vitro and in vivo approaches to investigate whether E2F2 and CCND2 are direct targets of let-7a, and if let-7a acts as a tumor suppressor in prostate cancer by down-regulating E2F2 and CCND2.Findings Real-time RT-PCR demonstrated that decreased levels of let-7a are present in resected prostate cancer samples and prostate cancer cell lines. Cellular proliferation was inhibited in PC3 cells and LNCaP cells after transfection with let-7a. Cell cycle analysis showed that let-7a induced cell cycle arrest at the G1/S phase. A dual-luciferase reporter assay demonstrated that the 3′UTR of E2F2 and CCND2 were directly bound to let-7a and western blotting analysis further indicated that let-7a down-regulated the expression of E2F2 and CCND2. Our xenograft models of prostate cancer confirmed the capability of let-7a to inhibit prostate tumor development in vivo.These findings help to unravel the anti-proliferative mechanisms of let-7a in prostate cancer. Let-7a may also be novel therapeutic candidate for prostate cancer given its ability to induce cell-cycle arrest and inhibit cell growth, especially in hormone-refractory prostate cancer

Changes in Physicochemical Properties and Flavor Characteristics of Rosa roxburghii Tratt. Fruit Vinegar during Fermentation

This paper investigated the compositional changes of Rosa roxburghii Tratt. fruit vinegar during fermentation. By using Rosa roxburghii Tratt. as raw material and using the whole liquid fermentation technique, fruit vinegar was prepared by fermenting alcoholic and acetic acids simultaneously. The physicochemical properties of the fermentation process were dynamically monitored. Headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and the odor activity value (OAV) were utilized to analyze volatile flavor components. As fermentation proceeded, soluble solids, pH, total sugars, and reduced sugars decreased, while total acid and VC contents increased. From the original juice to the end of acetic acid fermentation, the total acid and VC contents ranged from 1.86 g/100 mL and 956.82 mg/100 mL to 6.79 g/100 mL and 1275.88 mg/100 mL. Oxalic acid, quinic acid, pyruvic acid, ascorbic acid, lactic acid, acetic acid, and fumaric acid showed varying degrees of increasing (P<0.05). By contrast, formic acid, citric acid, maleic acid, and succinic acid exhibited little variation. A total of 92 volatile compounds were detected in the Rosa roxburghii Tratt. fruit vinegar, and with the addition of OAV analysis, ten volatile compounds were identified as key aroma compounds, which included nonanal, acetaldehyde, ethyl isobutyrate, ethyl butyrate, ethyl 2-methylbutyrate, ethanol, isoamyl alcohol, leaf alcohol, linalool, and phenyl ethanol. Among these components, ethyl butyrate and leaf alcohol contributed most to the aroma of Rosa roxburghii Tratt. fruit vinegar. Green grass and green apples were characteristic aromas of this vinegar. The results of the study would provide a theoretical basis and practical guidance for the effective control of fermentation conditions, revealing the physicochemical characteristics and flavor features of fermented Rosa roxburghii Tratt. fruit vinegar, forming a method for quality evaluation of Rosa roxburghii Tratt. fruit vinegar, and formulating quality standards

Quantified mass loss of the Laohugou ice core and its precipitation signal during 1961–2005 at high elevation in the northeastern Tibetan Plateau

Ice records provide a qualitative rather than a quantitative indication of the trend of climate change. Using the bulk aerodynamic method and degree day model, this study quantified ice mass loss attributable to sublimation/evaporation (S/E) and meltwater on the basis of integrated observations (1960–2006) of glacier-related and atmospheric variables in the northeastern Tibetan Plateau. During 1961–2005, the average annual mass loss in the ice core was 95.33 ± 20.56 mm w.e. (minimum: 78.97 mm w.e. in 1967, maximum: 146.67 mm w.e. in 2001), while the average ratio of the revised annual ice accumulation was 21.2 ± 7.7% (minimum: 11.0% in 1992, maximum 44.8% in 2000). A quantitative formula expressing the relationship between S/E and air temperature at the monthly scale was established, which could be extended to estimation of S/E changes of other glaciers in other regions. The elevation effect on alpine precipitation determined using revised ice accumulation and instrumental data was found remarkable. This work established a method for quantitative assessment of the temporal variation in ice core mass loss, and advanced the reconstruction of long-term precipitation at high elevations. Importantly, the formula established for reconstruction of S/E from temperature time series data could be used in other regions

Guanylate-binding Protein 1 (GBP1) contributes to the immunity of human mesenchymal stromal cells against toxoplasma gondii

Mesenchymal stromal cells (MSCs) have recently been shown to play important roles in mammalian host defenses against intracellular pathogens, but the molecular mechanism still needs to be clarified. We confirmed that human MSCs (hMSCs) pre-stimulated with IFN-γ showed a significant and dose-dependent ability to inhibit the growth of two types of Toxoplasma gondii (type I strain RH/GFP or type II strain PLK/RED). However, in contrast to previous reports, the anti-T. gondii activity of hMSCs was not mediated by indoleamine 2,3-dioxygenase (IDO). Genome-wide RNA-seq analysis revealed that IFN-γ increased the expression of the p65 family of guanylate-binding proteins (hGBPs) in hMSCs, especially hGBP1. To analyze the functional role of hGBPs, stable knockdowns of hGBP1, -2, -5 in hMSCs were established using a lentiviral transfection system. hGBP1 knockdown in hMSCs resulted in a significant loss of the anti-T. gondii host defense property, compared with hMSCs infected with non-targetted control sequences. hGBP2 and -5 knockdowns had no effect. Moreover, the hGBP1 accumulation on the parasitophorous vacuole (PV) membranes of IFN-γ-stimulated hMSCs might protect against T. gondii infection. Taken together, our results suggest that hGBP1 plays a pivotal role in anti-T. gondii protection of hMSCs and may shed new light on clarifying the mechanism of host defense properties of hMSCs

SARS-associated Coronavirus Transmitted from Human to Pig

Severe acute respiratory syndrome–associatedcoronavirus (SARS-CoV) was isolated from a pig during a survey for possible routes of viral transmission after a SARS epidemic. Sequence and epidemiology analyses suggested that the pig was infected by a SARS-CoV of human origin

Experimental Gaussian Boson Sampling

Gaussian Boson sampling (GBS) provides a highly efficient approach to make use of squeezed states from parametric down-conversion to solve a classically hard-to-solve sampling problem. The GBS protocol not only significantly enhances the photon generation probability, compared to standard boson sampling with single photon Fock states, but also links to potential applications such as dense subgraph problems and molecular vibronic spectra. Here, we report the first experimental demonstration of GBS using squeezed-state sources with simultaneously high photon indistinguishability and collection efficiency. We implement and validate 3-, 4- and 5-photon GBS with high sampling rates of 832 kHz, 163 kHz and 23 kHz, respectively, which is more than 4.4, 12.0, and 29.5 times faster than the previous experiments. Further, we observe a quantum speed-up on a NP-hard optimization problem when comparing with simulated thermal sampler and uniform sampler.Comment: 12 pages, 4 figures, published online on 2nd April 201

Single-cell analysis reveals the COL11A1+ fibroblasts are cancer-specific fibroblasts that promote tumor progression

Background: Cancer-associated fibroblasts (CAFs) promote tumor progression through extracellular matrix (ECM) remodeling and extensive communication with other cells in tumor microenvironment. However, most CAF-targeting strategies failed in clinical trials due to the heterogeneity of CAFs. Hence, we aimed to identify the cluster of tumor-promoting CAFs, elucidate their function and determine their specific membrane markers to ensure precise targeting.Methods: We integrated multiple single-cell RNA sequencing (scRNA-seq) datasets across different tumors and adjacent normal tissues to identify the tumor-promoting CAF cluster. We analyzed the origin of these CAFs by pseudotime analysis, and tried to elucidate the function of these CAFs by gene regulatory network analysis and cell-cell communication analysis. We also performed cell-type deconvolution analysis to examine the association between the proportion of these CAFs and patients’ prognosis in TCGA cancer cohorts, and validated that through IHC staining in clinical tumor tissues. In addition, we analyzed the membrane molecules in different fibroblast clusters, trying to identify the membrane molecules that were specifically expressed on these CAFs.Results: We found that COL11A1+ fibroblasts specifically exist in tumor tissues but not in normal tissues and named them cancer-specific fibroblasts (CSFs). We revealed that these CSFs were transformed from normal fibroblasts. CSFs represented a more activated CAF cluster and may promote tumor progression through the regulation on ECM remodeling and antitumor immune responses. High CSF proportion was associated with poor prognosis in bladder cancer (BCa) and lung adenocarcinoma (LUAD), and IHC staining of COL11A1 confirmed their specific expression in tumor stroma in clinical BCa samples. We also identified that CSFs specifically express the membrane molecules LRRC15, ITGA11, SPHK1 and FAP, which could distinguish CSFs from other fibroblasts.Conclusion: We identified that CSFs is a tumor specific cluster of fibroblasts, which are in active state, may promote tumor progression through the regulation on ECM remodeling and antitumor immune responses. Membrane molecules LRRC15, ITGA11, SPHK1 and FAP could be used as therapeutic targets for CSF-targeting cancer treatment