The microstructure and mechanical properties of an extruded Mg-12Dy-1.1Ni alloy have been investigated in this paper. The microstructure of the as-extruded alloy consisted of α-Mg matrix, Mg2Dy phase ...and a lamellar long-period stacking order (LPSO) phase distributed along the extrusion direction. Ageing the extruded alloy at 250 °C showed double peaks at 54 h and 108 h during ageing. The first ageing peak was due to a high number density of blocky 18R LPSO phases in conjunction with the precipitation of underaged 14H LPSO phase. The second ageing peak mainly arose from the precipitation of high volume fraction of 14H LPSO phases in the grain interior. Tensile testing indicated that the extruded alloy aged for 108 h exhibited the highest yield and ultimate tensile strengths from room temperature to 300 °C. The high tensile strengths of the alloy are mainly attributed to grain refinement and precipitation strengthening of 14H LPSO phase and dispersion strengthening of blocky 18R LPSO phase.
Normal aging is associated with significant alterations in brain's vascular structure and function, which can lead to compromised cerebral circulation and increased risk of neurodegeneration. The ...in vivo examination of cerebral blood flow (CBF), including capillary beds, in aging brains with sufficient spatial detail remains challenging with current imaging modalities. In the present study, we use 3-dimensional (3-D) quantitative optical coherence tomography angiography (OCTA) to examine characteristic differences of the cerebral vasculatures and hemodynamics at the somatosensory cortex between old (16 months old) and young mice (2 months old) in vivo. The quantitative metrics include cortical vascular morphology, CBF, and capillary flow velocity. We show that compared with young mice, the pial arterial tortuosity increases by 14%, the capillary vessel density decreases by 15%, and the CBF reduces by 33% in the old mice. Most importantly, changes in capillary velocity and heterogeneity with aging are quantified for the first time with sufficiently high statistical power between young and old populations, with a 21% (p < 0.05) increase in capillary mean velocity and 19% (p ≤ 0.05) increase in velocity heterogeneity in the latter. Our findings through noninvasive imaging are in line with previous studies of vascular structure modification with aging, with additional quantitative assessment in capillary velocity enabled by advanced OCTA algorithms on a single imaging platform. The results offer OCTA as a promising neuroimaging tool to study vascular aging, which may shed new light on the investigations of vascular factors contributing to the pathophysiology of age-related neurodegenerative disorders.
The aim of this study was to explore changes in morphological and mechanical properties of lower-limb skeletal muscles in patients with diabetes with and without diabetic peripheral neuropathy (DPN) ...and seek to find a potential image indicator for monitoring the progress of DPN in patients with type 2 diabetes mellitus (T2DM). A total of 203 patients with T2DM, with and without DPN, were included in this study. Ultrasonography and ultrasound shear wave imaging (USWI) of the abductor hallux (AbH), tibialis anterior (TA), and peroneal longus (PER) muscles were performed for each subject, and the shear wave velocity (SWV) and cross-sectional area (CSA) of each AbH, TA, and PER were measured. The clinical factors influencing AbH_CSA and AbH_SWV were analyzed, and the risk factors for DPN complications were investigated. AbH_CSA and AbH_SWV in the T2DM group with DPN decreased significantly (P < 0.05), but no significant differences were found in the SWV and CSA of the TA and PER between the two groups. Toronto Clinical Scoring System (CSS) score and glycosylated hemoglobin (HbA1c) were independent predictors of AbH_CSA and AbH_SWV. As AbH_SWV and AbH_CSA decreased, Toronto CSS score and HbA1c increased and incidence of DPN increased significantly. In conclusion, the AbH muscle of T2DM patients with DPN became smaller and softer, while its morphological and mechanical properties were associated with the clinical indicators related to the progression of DPN. Thus, they could be potential imaging indicators for monitoring the progress of DPN in T2DM patients.
Optical packet switching (OPS) networks are promising to accommodate the growing traffic and reduce power consumption in data center communications. OPS networks with nanosecond switching time ...require nanosecond clock and data recovery (CDR) circuits. The nanosecond CDR can be achieved by utilizing a global frequency-synchronized reference clock for both transmitters (TX) and receivers (RX) and adopting a phase compensation scheme, which leads to predictably managed frequency and phase. However, the CDR still needs to be comprehensively evaluated considering various interferes. We add more analysis by developing a novel optoelectronic co-simulation system that combines the software Opti-system and MATLAB/Simulink. We set up a simple OPS network equipped with the CDR architecture using the simulation system. The feasibility of the CDR mechanism is validated, then various interferes are characterized to evaluate the CDR's stability, including the location variation of reference clock source, channel jitters, and carrier power variations.
Objective
(1) To evaluate the effects of surgery and conservative treatments for cervical spondylotic radiculopathy and (2) provide reference for choosing the time and method of treatment.
Methods
A ...literature search was performed using PubMed, EMbase, The Cochrane Library, Web of Science, and ClinicalTrials from inception to September 2021. Randomized controlled trials (RCTs) on the use of surgery or conservative Treatments in Cervical Spondylotic Radiculopathy (CSR) were selected. The primary outcomes were the neck and arm visual analog scale (VAS) and Neck Disability Index (NDI). Secondary outcomes included active range of cervical motion (ROM) and Mental Health. Two reviewers proceeded study selection and quality assessment.
Results
A total of 6 studies, which comprised a total of 464 participants were included in the final meta-analysis. Compared with conservative treatment, surgical treatment was more effective in lowering Neck-VAS (<3 m: MD = −29.44, 95% CI = (–41.62,–17.27), P < .00001; 3–6 M: MD = −20.97, 95% CI = (–26.36,–15.57), P < .00001; 6 M: MD = −13.40, 95% CI = (–19.39, −7.41), P<.0001; 12 M: MD=−15.53, 95% CI=(-28.38, −2.68), P=.02), Arm-VAS(<3 m: MD = −33.52, 95% CI = (–39.89, −27.16), P < .00001; 3-6 M: MD = −20.97, 95% CI = (–26.36, −15.57), P < .00001; 6 M: MD = −17.52, 95% CI=(–23.94, −11.11), P < .0001; 12 M: MD = −21.91, 95% CI=(–27.09, −16.72), P < .00001) and NDI (<3 m: MD = −8.89, 95% CI = (–11.17, −6.61), P < .00001; 6 M: MD = −5.14, 95% CI = (–7.60, −2.69), P < .0001). No significant difference was observed in NDI at 12-month time point (MD = −5.17, 95% CI = (–12.33, 2.00), P = .16), ROM(MD = 2.91, 95% CI = (–4.51, 10.33), P = .77) and Mental Health (MD = .05, 95% CI=(–.24, .33), P = .74).
Conclusion
The 6 included studies that had low risk of bias, providing high-quality evidence for the surgical efficacy of CSR. The evidence indicates that surgical treatment is better than conservative treatment in terms of VAS score and NDI score, and superior to conservative treatment in less than one year. There was no evidence of a difference between surgical and conservative care in ROM and mental health. A small sample study with a follow-up of 5 to 8 years showed that surgical treatment was still better than conservative treatment, but the sample size was small and the results should be carefully interpreted.
Compared with conservative treatment, surgical treatment had a faster onset of response, especially in pain relief, but did not have a significant advantage in range of motion or NDI. This seems to mean that for patients with severe or even unbearable pain, the benefits of surgery as soon as possible will be significant. Although it is not clear whether the short-term risks of surgery are outweighed by the long-term benefits, rapid pain relief is necessary. Conservative treatment (including medical exercise therapy, mechanical cervical tractions, transcutaneous electrical nerve stimulation, pain management education, and cervical collar) once or twice a week for 3 months is beneficial in the long term and avoids the risks of surgery. In consideration of the good natural history of CSR and the relatively good outcome of conservative treatment (although symptom relief is slow), we think that surgery is not necessary for patients who do not need rapid pain relief.
Dysregulated microRNAs (miRNAs) play crucial roles in the occurrence and development of multiple tumours, but their roles in the progression of nasal squamous cell carcinoma (NSCC) remain unknown. ...The aim of our study was to investigate the potential function and molecular mechanism of miR-143-3p in NSCC. Expression of miRNA and mRNA was detected by quantitative real-time reverse transcription-PCR (qRT-PCR). Forced overexpression of miR-143-3p was established by transfecting mimics into NSCC cell line. Then, we investigated the role of miR-143-3p in human NSCC cell proliferation, apoptosis, cycle and migration by using MTT, flow cytometry and transwell assays. Bioinformatics analysis, qRT-PCR, Western blot and luciferase reporter analysis were performed to validate the relationship between miR-143-3p and its potential targets. We found that miR-143-3p was substantially downregulated in human NSCC tissues and cell line. Forced upregulation of miR-143-3p significantly attenuated cell proliferation and migration. Furthermore, this change could induce apoptosis and G1-phase arrest of NSCC cells. Mechanistically, miR-143-3p directly targeted and significantly suppressed Bcl-2 and IGF1R expression. In summary, miR-143-3p regulation of the proliferation, apoptosis, cell cycle and migration of NSCC probably partly depends on inhibition of Bcl-2 and IGF1R, indicating that miR-143-3p may be a novel molecular therapeutic target for NSCC.
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•MiR-143-3p is substantially low-expressed in human NSCC tissues and cell line.•MiR-143-3p can regulate the growth and migration of NSCC cells via directly targeting Bcl-2 and IGF1R.•MiR-143-3p may be a novel molecular therapeutic target for NSCC.
In vivo imaging of mouse brain vasculature typically requires applying skull window opening techniques: open-skull cranial window or thinned-skull cranial window. We report non-invasive 3D in vivo ...cerebral blood flow imaging of C57/BL mouse by the use of ultra-high sensitive optical microangiography (UHS-OMAG) and Doppler optical microangiography (DOMAG) techniques to evaluate two cranial window types based on their procedures and ability to visualize surface pial vessel dynamics. Application of the thinned-skull technique is found to be effective in achieving high quality images for pial vessels for short-term imaging, and has advantages over the open-skull technique in available imaging area, surgical efficiency, and cerebral environment preservation. In summary, thinned-skull cranial window serves as a promising tool in studying hemodynamics in pial microvasculature using OMAG or other OCT blood flow imaging modalities.
The Multi-Transmitting Formula (MTF) proposed by Liao et al. is a local artificial boundary condition widely used in numerical simulations of wave propagation in an infinite medium, while the drift ...instability is usually caused in its numerical implementation. In view of a physical interpretation of the Gustafsson, Kreiss and Sundström criterion on numerical solutions of initial-boundary value problems in the hyperbolic partial differential equations, the mechanism of the drift instability of MTF was discussed, and a simple measure for eliminating the drift instability was proposed by introducing a modified operator into the MTF. Based on the theory of spherical wave propagation and damping effect of medium, the physical implication on modified operator was interpreted. And the effect of the modified operator on the reflection coefficient of MTF was discussed. Finally, the validity of the proposed stable implementation measure was verified by numerical tests of wave source problem and scattering problem.
Diecastings of the A356 aluminum alloy were produced by rheo-diecasting (RDC) and High pressure die casting (HPDC), the microstructures of primary solidification, secondary solidification and ...eutectic Si of diecastings with different pouring temperature were explored and the mechanical properties of different parameters were tested. The result shows that the primary α-Al grains in RDC with self-inoculation method (SIM) are smaller and rounder than the dendrite structure in HPDC. During the RDC process, the amount of primary α-Al grains, average grain size and the lamellar spacing of the eutectic Si increase with the decrease of the melt treatment temperature. While the average grain size and the shape factor are gradually increasing with the increase of melt treatment temperature. As a result, RDC can significantly improve the mechanical properties of the A356 aluminum alloy compared with HPDC, the mechanical properties are optimal at 600°Cwith the tensile strength and elongation are 268.67MPa and 6.8%, respectively.
The use of coal as a precursor for producing hard carbon is favored due to its abundance, low cost, and high carbon yield. To further optimize the sodium storage performance of hard carbon, the ...introduction of heteroatoms has been shown to be an effective approach. However, the inert structure in coal limits the development of heteroatom-doped coal-based hard carbon. Herein, coal-based P-doped hard carbon was synthesized using Ca
(PO
)
to achieve homogeneous phosphorus doping and inhibit carbon microcrystal development during high-temperature carbonization. This involved a carbon dissolution reaction where Ca
(PO
)
reacted with SiO
and carbon in coal to form phosphorus and CO. The resulting hierarchical porous structure allowed for rapid diffusion of Na
and resulted in a high reversible capacity of 200 mAh g
when used as an anode material for Na
storage. Compared to unpretreated coal-based hard carbon, the P-doped hard carbon displayed a larger initial coulombic efficiency (64%) and proportion of plateau capacity (47%), whereas the unpretreated carbon only exhibited an initial coulombic efficiency of 43.1% and a proportion of plateau capacity of 29.8%. This work provides a green, scalable approach for effective microcrystalline regulation of hard carbon from low-cost and highly aromatic precursors.
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