For conventional titanium matrix composites (TiMCs), there is always a trade-off issue between enhanced strength and ductility of these materials. In this study, we explore a new design methodology ...by reinforcing titanium alloy matrix with carbonaceous nanomaterials and investigate the mechanisms for achieving a good balance of their strength and ductility. The TiMCs were synthesized through a low-cost powder metallurgy route using pre-mixed Ti-6Al-4V (TC4) powders and various carbon based nanofillers, including graphite powders (GPs), graphene oxide nanosheets (GONs) and graphene nanoplates (GNPs), and were further rolled at a temperature of 1173 K with a deformation of 66.7%. Among these three types of carbon reinforcing sources, the GNPs are more easily reacted with TC4 matrix and form more contents of TiC phases after sintering owing to their larger amounts of defects than those of the GPs and GONs. TiC products are identified to play a bridging role for not only connecting the TC4 matrix but also forming coherent interfaces with the TC4 matrix, thus facilitating a strong interfacial bonding of the composites. The as-rolled GNPs/TC4 composites exhibit a 0.2% yield strength of 1146.36 MPa (with an elongation of ∼8.1%), which is 24.6%, 9.22% and 5.62% higher than those of pure TC4, GPs/TC4 and GONs/TC4 composites. The GNPs/TC4 nanocomposites show a better balance of strength and ductility than those of the other two types of nanocomposites. The synergetic strengthening mechanisms are identified to be Orowan strengthening effect, effective load transfer capability of GNPs, and in-situ formation of interfacial TiC structures, which provide optimum interfacial microstructures to achieve good mechanical properties of the TiMCs.
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Temperature distribution characteristics are important for evaluating the combustion status, safety monitoring, and disaster diagnosis of combustible gases. Traditional colorimetric thermometry is ...difficult to measure the temperature of combustible gases for the lack of the grey-body in the burning processes. In the present study, a visible burning facility for combustible gases is designed, and the temperature characteristics are measured using an improved colorimetric pyrometer with auxiliary solid powders as a grey-body. In order to improve the temperature measurement accuracy of the system, the type, particle size, and concentration of the powders as well as the ignition delay time are studied. After many debugging experiments, it is found that the best measurement results are obtained for the 30/70 H
2
/air mixture with the tungsten powder with the mean particle size of 7.9
m, particle concentration of 21 g/m
3
, and ignition delay time of 80 ms. The results are corroborated with the previous studies.
Characteristics of diode-wing-pumped highly efficient Tm:LuAG lasers running both in continuous wave (CW) and electro-optical Q-switching regimes have been investigated. Using a simple plane-plane ...cavity, a maximum CW output power of 8.5 W has been achieved with a corresponding slope efficiency of 44.5% by "wing pumping" at 790 nm. With a V-shaped cavity, a diode-wing-pumped MgO:LiNbO
crystal based electro-optically Q-switched Tm:LuAG laser at 2022.9 nm delivered a maximum pulse energy of 10.8 mJ and a minimum pulse width of 52 ns at a corresponding repetition rate of 100 Hz. To the best of our knowledge, the achieved CW output power and Q-switched pulse energy have both set records for all-solid-state Tm:LuAG lasers, which well reveals an efficient way to generate high-power and high-energy lasers at 2 μm wavelength.
Real-time ultrasound imaging has been used for the evaluation of pulmonary abnormalities and other complications during the outbreak of COVID-19. However, conventional ultrasound examination requires ...operators to conduct scanning either in the examination room or patient ward, which may increase the potential infective risk. Tele-operated ultrasound robotics can provide a unique technique for doctors to remotely scan patients. During the COVID-19 pandemic, we attempted to apply a 5G network-based scanning robot to conduct remote ultrasound examination on COVID-19 patients and to explore the feasibility of this technique for teleultrasound diagnosis and consultation during critical infectious situations.
Haploidentical hematopoietic SCT (haplo-HSCT) is to be established in patients with acquired severe aplastic anemia (SAA) refractory to immunosuppressive therapy and lacking HLA-matched related or ...unrelated donors. Graft failure (GF) and GVHD have been major obstacles to HSCT. A total of 17 children and adolescents with SAA underwent haplo-HSCT in our center. The conditioning regimen consisted of BU, fludarabine, CY and anti-thymocyte globulin. All patients received cyclosporine, short-term MTX, mycophenolate mofetil and basiliximab for GVHD prophylaxis. Mesenchymal stem cells derived from unrelated umbilical cord were infused on day 1. Neutrophil engraftment was achieved in all 17 patients in a median time of 16 days (range 9-25 days). The median time of platelet engraftment was 22 days (range 9-95 days) in 16 patients. The cumulative incidence (CI) of II-IV acute GVHD (aGVHD) at day +100 was 30.53±11.12% and III-IV aGVHD occurred in only one patient. The CI of chronic GVHD was 21.25±13.31%. Secondary GF with autologous hematopoiesis recovery occurred in one patient. The OS was 71.60±17.00% at a median follow-up of 362 (36-1321) days. These limited promising data suggest that haplo-HSCT is feasible as a salvage therapy for children and adolescents with refractory SAA who lack matched donors.
Background
Aerobic glycolysis has a pivotal role in the carcinogenic process. The current understanding of the functional role and mechanism of UCHL3-related aerobic glycolysis in pancreatic cancer ...is far from comprehensive, therefore requires an in-depth analysis on this aspect.
Methods
In the present research, the expressions of ubiquitin carboxyl-terminal hydrolase L3 (UCHL3), lactate dehydrogenase A (LDHA) and Forkhead box protein M1 (FOXM1) were detected by qRT-PCR, Western blot and immunohistochemistry. The effects of UCHL3 knockdown or overexpression on pancreatic cancer cells were examined by determining cell viability and colony formation. Aerobic glycolysis was assessed according to glucose uptake, lactic acid production, and lactate dehydrogenase (LDH) activity. Dual-luciferase reporter assay was performed to detect LDHA promoter activity.
Results
The results showed that UCHL3 expression was significantly increased in the pancreatic cancer tissues and cells, and that knocking down UCHL3 noticeably inhibited cell viability and aerobic glycolysis. Further investigations revealed that LDHA expression was promoted by UCHL3 and could be reduced by shFOXM1, and that low-expressed LDHA partly reversed the inhibition of aerobic glycolysis induced by overexpressed UCHL3.
Conclusions
To conclude, this study demonstrates that UCHL3 plays a carcinogenic role by promoting aerobic glycolysis in pancreatic cancer, suggesting that UCHL3 may be a potential diagnostic and therapeutic target for the treatment of cancer.
Summary
Manila clam, Ruditapes philippinarum, is an economically important marine bivalve species. Y‐box proteins are members of the cold shock proteins family and highly conserved from bacteria to ...humans. In this study, a novel Y‐box gene (Rpybx) was cloned from the Manila clam and gene expression profiling was performed on three shell color strains (white, zebra and white zebra) and two wild populations (Southern and Northern) of R. philippinarum. The complete ORF length of Rpybx is 1367 bp, encoding 253 amino acids residues. Based on the amino acid sequence analysis and phylogenetic analysis, the Rpybx gene was identified as a member of the invertebrate Y‐box proteins family. Rpybx has a similar tertiary structure to human Y‐box protein YB‐1. The Rpybx mRNA levels were analyzed by qPCR under acute and gradually varied cold stress. Under acute low‐temperature stress, the expression of Rpybx mRNA in gills and hepatopancreas was significantly increased in all selected strains and populations (P < 0.05). The Northern population showed the lowest relative expression level of Rpybx. The expressions of Rpybx were greatly upregulated in gills and hepatopancreas of different stains and populations at 5 or −2°C under gradually varied temperature stress (P < 0.05). The results shed light on the biological function of the Rpybx gene in defending against low‐temperature challenge and further exploring the molecular mechanism of cold tolerance and resistance in R. philippinarum.
Carbon dioxide corrosion is one of the important degradation mechanism for carbon steel pipelines in the oil sands, oil and gas industries. Such type of corrosion has attracted considerable attention ...due to the increased tendency to inject CO2 into oil wells to reduce the viscosity of oil for increased production. When erosion is involved, the synergy of corrosion and erosion can significantly accelerate the failure of steel pipelines. It has been noticed that CO2 corrosion of carbon steel is influenced by the level of dissolved oxygen (DO) in solution. Since DO level in the sections of pipeline at distance from inlets can be considerably lowered due to the oxidation of substances in the transported solutions, the damage to pipelines caused by erosion–corrosion varies in different sections. In this study, erosion–corrosion of a pipeline steel (X65) in aqueous slurries containing silica sand and CO2 at different dissolved oxygen (DO) levels was investigated. It was demonstrated that the damage to the steel was increased when CO2 was blown into the slurry. However, when CO2 was blown at a much higher pressure, which significantly reduced the DO level of the slurry, the weight loss was lower than that in open air without CO2, indicating that the dissolved oxygen considerably enhanced the CO2 corrosion and the erosion–corrosion synergy. Thus, CO2 could play a more destructive role in the vicinity of pipeline inlets. Besides, the destructive effect of CO2 on the steel was stronger at lower slurry velocities. Efforts were made to clarify relevant mechanisms responsible for the observed phenomena.
Dose-dependent association between hyperintensity in deep brain structures on unenhanced T1WIs and gadolinium-based contrast agent administrations has been demonstrated with subsequent ...histopathological confirmation of gadolinium deposition. Our aim was to determine whether greater exposure to linear gadolinium-based contrast agent administration is associated with higher signal intensity in deep brain structures on unenhanced T1-weighted MR imaging. Secondary objective was to compare signal intensity differences between ionic and nonionic linear gadolinium-based contrast agents.
Subjects with secondary-progressive MS originally enrolled in a multicenter clinical trial were studied retrospectively. Eighty subjects (high-exposure cohort) received 9 linear gadolinium-based contrast agent administrations (30 nonionic/50 ionic) between week -4 and year 1 and a tenth administration by year 2. One hundred fifteen subjects (low-exposure cohort) received 2 administrations (40 nonionic/75 ionic) between week -4 and year 1 and a third administration by year 2. Signal intensities were measured on unenhanced T1WIs by placing sample-points on the dentate nucleus, globus pallidus, caudate, thalamus, pons, and white matter, and they were normalized using the following ratios: dentate/pons, globus pallidus/white matter, caudate/white matter, and thalamus/white matter.
Between week -4 and year 1, subjects in the high-exposure cohort showed increased signal intensity ratios in all regions (
< .01), while the low-exposure cohort showed only an increase in the dentate nucleus (
= .003). Between years 1 and 2, when both cohorts received only 1 additional gadolinium-based contrast agent, no significant changes were observed. In the high-exposure cohort, significantly higher changes in signal intensity ratios were observed in subjects receiving linear nonionic than in those receiving linear ionic gadolinium-based contrast agents.
Hyperintensity in deep brain structures from gadolinium deposition is related to the number of doses and the type of linear gadolinium-based contrast agent (nonionic greater than ionic) administration.
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