Based on the idea of suppressing submicron particle escape effectively by applying magnetic field, we propose a novel model design of outer vortex electrostatic cyclone precipitator (ECP) and ...establish a theoretical model under four-field coupling interaction. The influences of temperature and working voltage on the escape rate of submicron particles with or without magnetic confinement effect are subsequently evaluated. The results indicate that magnetic confinement effect can availably reduce submicron particle escape in ECP. Whether magnetic field exists or not, high working voltage and low temperature are more favorable to confine submicron particles to collection wall surface, however, the increasing effect of low working voltage on the trapping performance is bigger, and the weakening effect of temperature under magnetic confinement effect is smaller than that under non magnetic field. At a certain working voltage or temperature, the enhancing effect of magnetic field on collection efficiency progressively decreases with the increasing magnetic flux density, and the smaller the magnetic flux density is, the stronger the ability of magnetic confinement becomes. The research results provide assistance for designing newly effective ECP and applying magnetic confinement technique to reduce submicron particle escape in industrial applications.
Display omitted
•A new outer vortex ECP model design is proposed by applying magnetic confinement.•A theoretical model with four-field coupling interaction is established.•The escape rate of submicron particles with or without magnetic field is explored.•Magnetic confinement effect can availably reduce the submicron particle escape.•Magnetic confinement effect is better at high temperature or low working voltage.
Trimodal therapy (neoadjuvant chemoradiotherapy followed by esophagectomy) for locally advanced esophageal squamous cell carcinoma (ESCC) is associated with a significant survival benefit. Modified ...Ryan score is an effective tool to evaluated the tumor regression grade (TRG) after neoadjuvant therapy. The aim of this study was to evaluate the prognostic value of TRG for overall survival (OS) and disease-free survival (DFS) in ESCC patients undergoing neoadjuvant chemoradiation.
The study retrospectively reviewed 523 ESCC patients who underwent neoadjuvant chemoradiotherapy and radical esophagectomy at Jinling Hospital from January 2014 to July 2020. Kaplan-Meier curves with log-rank test and Cox regression model were used to evaluate the prognostic factor of TRG based on modified Ryan scoring system on OS and DFS.
After application of inclusion and exclusion criteria, 494 patients with ESCC following neoadjuvant chemoradiotherapy and radical esophagectomy were available for analysis. The TRG scores are significantly associated with smoke history (
= 0.02), lymphovascular invasion (LVI) and/or peripheral nerve invasion (PNI) (
< 0.01), and postoperative adjuvant therapy (
< 0.01). Meanwhile, tumor characteristics including tumor length (
< 0.01) and tumor differentiation grade (
< 0.01) are also significantly associated with TRG score. The results of multivariable Cox regression modal showed that TRG is not an independently prognostic factor for OS (
= 0.922) or DFS (
= 0.526) but tumor length is an independently prognostic factor for DFS (
= 0.046).
This study evaluated the prognostic value of modified Ryan scoring system for ESCC after trimodal therapy and concluded that modified Ryan scoring system can predict survival and recurrence rates but is not an independently prognostic factor for OS and DFS.
Abstract Background Fumarase catalyzes the reversible hydration of fumarate to L-malate and is a key enzyme in the tricarboxylic acid (TCA) cycle and in amino acid metabolism. Fumarase is also used ...for the industrial production of L-malate from the substrate fumarate. Thermostable and high-activity fumarases from organisms that inhabit extreme environments may have great potential in industry, biotechnology, and basic research. The marine environment is highly complex and considered one of the main reservoirs of microbial diversity on the planet. However, most of the microorganisms are inaccessible in nature and are not easily cultivated in the laboratory. Metagenomic approaches provide a powerful tool to isolate and identify enzymes with novel biocatalytic activities for various biotechnological applications. Results A plasmid metagenomic library was constructed from uncultivated marine microorganisms within marine water samples. Through sequence-based screening of the DNA library, a gene encoding a novel fumarase (named FumF) was isolated. Amino acid sequence analysis revealed that the FumF protein shared the greatest homology with Class II fumarate hydratases from Bacteroides sp. 2_1_33B and Parabacteroides distasonis ATCC 8503 (26% identical and 43% similar). The putative fumarase gene was subcloned into pETBlue-2 vector and expressed in E. coli BL21(DE3)pLysS. The recombinant protein was purified to homogeneity. Functional characterization by high performance liquid chromatography confirmed that the recombinant FumF protein catalyzed the hydration of fumarate to form L-malate. The maximum activity for FumF protein occurred at pH 8.5 and 55°C in 5 mM Mg2+. The enzyme showed higher affinity and catalytic efficiency under optimal reaction conditions: K m= 0.48 mM, V max = 827 μM/min/mg, and k cat/K m = 1900 mM/s. Conclusions We isolated a novel fumarase gene, fumF, from a sequence-based screen of a plasmid metagenomic library from uncultivated marine microorganisms. The properties of FumF protein may be ideal for the industrial production of L-malate under higher temperature conditions. The identification of FumF underscores the potential of marine metagenome screening for novel biomolecules.
Owing to unorganized point cloud data, unexpected triangles, such as holes and slits, may be generated during mesh surface reconstruction. To solve this problem, a mesh surface reconstruction method ...based on edge growing from unorganized point clouds is proposed. The method first constructs an octree structure for unorganized point cloud data, and determines the
k
-nearest neighbor for each point. Subsequently, the method searches for flat areas in the point clouds to be used as the initial mesh edge growth regions, to avoid incorrect reconstruction of the mesh surface owing to the growth of initial sharp areas. Finally, the optimal mesh surface is obtained by controlling the mesh edge growing based on compulsive restriction and comprehensive optimization criteria. The experimental results of mesh surface reconstruction show that the method is feasible and shows high reconstruction performance without introducing holes or slits in the reconstructed mesh surface.
Our pilot study suggested that noninvasive ventilation (NIV) reduced the need for intubation compared with conventional administration of oxygen on patients with "early" stage of mild acute ...respiratory distress syndrome (ARDS, PaO
/FIO
between 200 and 300).
To evaluate whether early NIV can reduce the need for invasive ventilation in patients with pneumonia-induced early mild ARDS.
Prospective, multicenter, randomized controlled trial (RCT) of NIV compared with conventional administration of oxygen through a Venturi mask. Primary outcome included the numbers of patients who met the intubation criteria.
Two hundred subjects were randomized to NIV (n = 102) or control (n = 98) groups from 21 centers. Baseline characteristics were similar in the two groups. In the NIV group, PaO
/FIO
became significantly higher than in the control group at 2 h after randomization and remained stable for the first 72 h. NIV did not decrease the proportion of patients requiring intubation than in the control group (11/102 vs. 9/98, 10.8% vs. 9.2%, p = 0.706). The ICU mortality was similar in the two groups (7/102 vs. 7/98, 4.9% vs. 3.1%, p = 0.721). Multivariate analysis showed minute ventilation greater than 11 L/min at 48 h was the independent risk factor for NIV failure (OR, 1.176 95% CI, 1.005-1.379, p = 0.043).
Treatment with NIV did not reduce the need for intubation among patients with pneumonia-induced early mild ARDS, despite the improved PaO
/FIO
observed with NIV compared with standard oxygen therapy. High minute ventilation may predict NIV failure.
NCT01581229 . Registered 19 April 2012.
Structural succession and its driving factors for nitrogen (N) cycling microbial communities during the early stages of soil development (0-44 years) were studied along a chronosequence in the ...glacial forelands of the Tianshan Mountain No.1 glacier in the arid and semi-arid region of central Asia. We assessed the abundance and population of functional genes affiliated with N-fixation (nifH), nitrification (bacterial and archaeal amoA), and denitrification (nirK/S and nosZ) in a glacier foreland using molecular methods. The abundance of functional genes significantly increased with soil development. N cycling community compositions were also significantly shifted within 44 years and were structured by successional age. Cyanobacterial nifH gene sequences were the most dominant N fixing bacteria and its relative abundance increased from 56.8-93.2% along the chronosequence. Ammonia-oxidizing communities shifted from the Nitrososphaera cluster (AOA-amoA) and the Nitrosospira cluster ME (AOB-aomA) in younger soils (0 and 5 years) to communities dominated by soil and sediment 1 (AOA-amoA) and Nitrosospira Cluster 2 Related (AOB-aomA) in older soils (≥17 years). Most of the denitrifers closest relatives were potential aerobic denitrifying bacteria, and some other types of denitrifying bacteria (like autotrophic nitrate-reducing, sulfide-oxidizing bacteria and denitrifying phosphorus removing bacteria) were also detected in all soil samples. The regression analysis showed that N cycling microbial communities were dominant in younger soils (0-5 years) and significantly correlated with soil total carbon, while communities that were most abundant in older soils were significantly correlated with soil total nitrogen. These results suggested that the shift of soil C and N contents during the glacial retreat significantly influenced the abundance, composition and diversity of N cycling microbial communities.
Nasopharyngeal carcinoma (NPC), which originates from the nasopharynx, is highly prevalent in Southern China and Southeast Asia, and more than 90% of all NPCs are non-keratinizing undifferentiated ...cells or poorly differentiated squamous cells. Cancer stem cells (CSCs) are capable of self-renewal and have differentiation potential. These properties form the basis of cancer initiation, development, and radiochemoresistance. However, the molecular mechanisms underlying NPC CSC maintenance remain poorly understood. Here, genomic expression profiling using our previously established monoclonal cellular and animal models revealed that interferon regulatory factor 6 (IRF6) was downregulated in highly metastatic NPC cells, cancer stem-like NPC cells and animal models. Functional assays revealed that elevated IRF6 expression suppressed cell proliferation, growth, CSCs properties and enhanced cell chemotherapeutic sensitivity. However, silencing IRF6 resulted in opposing effects. Moreover, we determined that as a tumor suppressor gene and transcription factor, IRF6 directly bound the upstream region of the ATP-binding cassette sub-family G member 2 (ABCG2) DNA element and suppressed target ABCG2 expression in NPC cells. Consistently, an inverse correlation was observed between the mRNA levels of IRF6 and ABCG2 in clinical NPC samples. With these results, we provide the first evidence that IRF6 directly targets the ABCG2 gene and selectively kills CSCs in NPC and that IRF6 may be a valuable tool for developing new CSC-targeted treatment strategies for undifferentiated NPC patients.
•IRF6 is initially found to be down regulated in our well established high-metastasis NPC cellular clone, and further series functional studies confirmed that IRF6 can inhibit the growth, migration, invasion, and metastasis of NPC cells.•Elevated IRF6 expression can enhance NPC chemotherapeutic sensitivity.•IRF6 down-regulates the expression of ABCG2 in NPC.•IRF6 can selectively kill nasopharyngeal carcinoma stem cells and overexpression of IRF6 is a promising approach for anti-stem cell targeted therapy.
The energy oriented mine ecological restoration mode of photovoltaic+ecological restoration provides a breakthrough for alleviating the dilemma of photovoltaic land development and solving the urgent ...need for restoration of abandoned mining land. Taking a mining area in central Liaoning Province as an example, we established three photovoltaic+mining ecological restoration modes, including forest-photovoltaic complementary, agriculture-photovoltaic, and grass photovoltaic complementation. Combined with the life cycle assessment method, we calculated and assessed the potential of photovoltaic+mining ecological restoration in carbon reduction and sink enhancement. The average annual carbon reduction and sink increase was 514.93 t CO2·hm-2 under the photovoltaic+mining ecological restoration mode, while the average annual carbon reduction per megawatt photovoltaic power station was 1242.94 t CO2. The adoption of photovoltaic+ecological restoration mode in this mining area could make carbon reduction and sink enh
PDF
