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Internal friction (IF, Q) behavior of C/SiC composites that were coated with two kinds of environment barrier coatings, scandium disilicate (ScSiO) and barium aluminosilicates (BaAlSiO, BAS), were investigated in corrosive environments. The ScSiO-coated C/SiC composites were subjected to 50%HO-50%O water vapor at 1400°C and BAS-coated C/SiC composites were exposed to molten NaSO coupled with 50%HO-50%O water vapor at 900°C. The values of Q for the samples corroded at different times were recorded by means of a forced nonresonant technique. The weight loss and flexural strength as a function of corrosion time were measured. The microstructural evolution of the corroded specimens at different periods was also studied. The results indicate that the value of Q of the coated C/SiC composites varies with their corrosion behaviors. The main factors that determine the IF behavior of the composites subjected to corrosion environments are the oxidation and corrosion of their fibers and interface. [ABSTRACT FROM AUTHOR]

Acoustic resonance induced by vortex shedding from a flat plate in a flow duct has been widely concerned in a variety of engineering applications. However, the unsteady vortex sound interaction is still an open issue. A nonlinear physical model is established based on three meshless sub-models, including the discrete vortex method (DVM) for vortex shedding, the vortex sound theory for sound radiation and the time-domain boundary element method (TDBEM) for sound propagation within the duct. Then, the feedback effect of sound wave is considered by adding acoustic particle velocity onto the potential flow of vortex shedding, which makes the coupling process bidirectional. Both the flow field, sound field and their unsteady interaction are obtained simultaneously. The predicted resonant frequency and amplitude results are in accordance with the previous experiment data, especially, the lock-in phenomenon is reasonably captured. By comparing the numerical results with and without acoustic feedback, it reveals that the feedback sound plays a significant role in the onset of lock-in phenomenon, including enhancing the strength and modulating the frequency of vortex shedding. It helps to get a more detailed insight into the underlying physical process of vortex sound interaction for studying control strategy. [ABSTRACT FROM AUTHOR]

A low-voltage and low-power 50/100-GHz transformer-based phase-locked loop (PLL) is implemented in a 65-nm CMOS technology. Consuming only 14.1 mW from a 0.6/1.2-V supply, the PLL measures phase noise of -90/-84 dBc/Hz at 100-kHz offset and -94/-88 dBc/Hz at 1-MHz offset at 49.7/99.4 GHz while occupying a core chip area of \0.39\ \mm^2. Moreover, with an embedded phase shifter, the PLL output phase can be shifted by a 360^\circ range with an average resolution of 3.9^\circ and amplitude variation less than \pm0.1 dB, which makes it suitable for phased-array transceivers. [ABSTRACT FROM AUTHOR]

Objectives: To compare the safety and efficiency of ultrasound-guided percutaneous radiofrequency ablation (RFA) and surgical resection (SR) for thyroid papillary carcinoma (PTC) in the danger triangle area.The clinical data of 298 patients who underwent either percutaneous RFA or SR for PTC in the thyroid danger triangle at our hospital between January 2018 and April 2020 were retrospectively analyzed. Propensity score matching is employed to regulate for confounding factors. All patients undergoing ablation were treated using a strategy that combined sufficient paratracheal fluid isolation with a low-power, short electrode. Disease progression was analyzed in patients with T1N0M0 PTC (T1a and T1b) employed in Kaplan‒Meier curves. Treatment parameters and the rates of local recurrence, distant metastasis, and complications are recorded and compared.Of 182 eligible patients who were included, 91 were in the RFA (age 44.84 ± 13.19; 71 females; 77 T1a) and 91 were in the SR (age 47.36 ± 11.05; 68 females; 69 T1a). The average treatment time, length of hospital stays, blood loss volume, and scar length are substantially less in the RFA than in the SR. Major complications as well as postoperative permanent recurrent laryngeal nerve injury and postoperative transient parathyroid dysfunction occurred only in the SR, with a substantial distinction between the two groups (p < 0.05). There is no substantial distinction in the disease progression between RFA and SR treatment of T1N0M0 PTC.RFA is as effective as surgery for PTC in the danger triangle area in the short term, with faster recovery and fewer complications.Radiofrequency ablation has a clinical efficacy comparable to surgery in the treatment of papillary thyroid carcinoma in the danger triangle area in the short term with the advantages of faster recovery and fewer complications when compared with surgery.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Methods: To compare the safety and efficiency of ultrasound-guided percutaneous radiofrequency ablation (RFA) and surgical resection (SR) for thyroid papillary carcinoma (PTC) in the danger triangle area.The clinical data of 298 patients who underwent either percutaneous RFA or SR for PTC in the thyroid danger triangle at our hospital between January 2018 and April 2020 were retrospectively analyzed. Propensity score matching is employed to regulate for confounding factors. All patients undergoing ablation were treated using a strategy that combined sufficient paratracheal fluid isolation with a low-power, short electrode. Disease progression was analyzed in patients with T1N0M0 PTC (T1a and T1b) employed in Kaplan‒Meier curves. Treatment parameters and the rates of local recurrence, distant metastasis, and complications are recorded and compared.Of 182 eligible patients who were included, 91 were in the RFA (age 44.84 ± 13.19; 71 females; 77 T1a) and 91 were in the SR (age 47.36 ± 11.05; 68 females; 69 T1a). The average treatment time, length of hospital stays, blood loss volume, and scar length are substantially less in the RFA than in the SR. Major complications as well as postoperative permanent recurrent laryngeal nerve injury and postoperative transient parathyroid dysfunction occurred only in the SR, with a substantial distinction between the two groups (p < 0.05). There is no substantial distinction in the disease progression between RFA and SR treatment of T1N0M0 PTC.RFA is as effective as surgery for PTC in the danger triangle area in the short term, with faster recovery and fewer complications.Radiofrequency ablation has a clinical efficacy comparable to surgery in the treatment of papillary thyroid carcinoma in the danger triangle area in the short term with the advantages of faster recovery and fewer complications when compared with surgery.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Results: To compare the safety and efficiency of ultrasound-guided percutaneous radiofrequency ablation (RFA) and surgical resection (SR) for thyroid papillary carcinoma (PTC) in the danger triangle area.The clinical data of 298 patients who underwent either percutaneous RFA or SR for PTC in the thyroid danger triangle at our hospital between January 2018 and April 2020 were retrospectively analyzed. Propensity score matching is employed to regulate for confounding factors. All patients undergoing ablation were treated using a strategy that combined sufficient paratracheal fluid isolation with a low-power, short electrode. Disease progression was analyzed in patients with T1N0M0 PTC (T1a and T1b) employed in Kaplan‒Meier curves. Treatment parameters and the rates of local recurrence, distant metastasis, and complications are recorded and compared.Of 182 eligible patients who were included, 91 were in the RFA (age 44.84 ± 13.19; 71 females; 77 T1a) and 91 were in the SR (age 47.36 ± 11.05; 68 females; 69 T1a). The average treatment time, length of hospital stays, blood loss volume, and scar length are substantially less in the RFA than in the SR. Major complications as well as postoperative permanent recurrent laryngeal nerve injury and postoperative transient parathyroid dysfunction occurred only in the SR, with a substantial distinction between the two groups (p < 0.05). There is no substantial distinction in the disease progression between RFA and SR treatment of T1N0M0 PTC.RFA is as effective as surgery for PTC in the danger triangle area in the short term, with faster recovery and fewer complications.Radiofrequency ablation has a clinical efficacy comparable to surgery in the treatment of papillary thyroid carcinoma in the danger triangle area in the short term with the advantages of faster recovery and fewer complications when compared with surgery.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Conclusion: To compare the safety and efficiency of ultrasound-guided percutaneous radiofrequency ablation (RFA) and surgical resection (SR) for thyroid papillary carcinoma (PTC) in the danger triangle area.The clinical data of 298 patients who underwent either percutaneous RFA or SR for PTC in the thyroid danger triangle at our hospital between January 2018 and April 2020 were retrospectively analyzed. Propensity score matching is employed to regulate for confounding factors. All patients undergoing ablation were treated using a strategy that combined sufficient paratracheal fluid isolation with a low-power, short electrode. Disease progression was analyzed in patients with T1N0M0 PTC (T1a and T1b) employed in Kaplan‒Meier curves. Treatment parameters and the rates of local recurrence, distant metastasis, and complications are recorded and compared.Of 182 eligible patients who were included, 91 were in the RFA (age 44.84 ± 13.19; 71 females; 77 T1a) and 91 were in the SR (age 47.36 ± 11.05; 68 females; 69 T1a). The average treatment time, length of hospital stays, blood loss volume, and scar length are substantially less in the RFA than in the SR. Major complications as well as postoperative permanent recurrent laryngeal nerve injury and postoperative transient parathyroid dysfunction occurred only in the SR, with a substantial distinction between the two groups (p < 0.05). There is no substantial distinction in the disease progression between RFA and SR treatment of T1N0M0 PTC.RFA is as effective as surgery for PTC in the danger triangle area in the short term, with faster recovery and fewer complications.Radiofrequency ablation has a clinical efficacy comparable to surgery in the treatment of papillary thyroid carcinoma in the danger triangle area in the short term with the advantages of faster recovery and fewer complications when compared with surgery.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Clinical relevance statement: To compare the safety and efficiency of ultrasound-guided percutaneous radiofrequency ablation (RFA) and surgical resection (SR) for thyroid papillary carcinoma (PTC) in the danger triangle area.The clinical data of 298 patients who underwent either percutaneous RFA or SR for PTC in the thyroid danger triangle at our hospital between January 2018 and April 2020 were retrospectively analyzed. Propensity score matching is employed to regulate for confounding factors. All patients undergoing ablation were treated using a strategy that combined sufficient paratracheal fluid isolation with a low-power, short electrode. Disease progression was analyzed in patients with T1N0M0 PTC (T1a and T1b) employed in Kaplan‒Meier curves. Treatment parameters and the rates of local recurrence, distant metastasis, and complications are recorded and compared.Of 182 eligible patients who were included, 91 were in the RFA (age 44.84 ± 13.19; 71 females; 77 T1a) and 91 were in the SR (age 47.36 ± 11.05; 68 females; 69 T1a). The average treatment time, length of hospital stays, blood loss volume, and scar length are substantially less in the RFA than in the SR. Major complications as well as postoperative permanent recurrent laryngeal nerve injury and postoperative transient parathyroid dysfunction occurred only in the SR, with a substantial distinction between the two groups (p < 0.05). There is no substantial distinction in the disease progression between RFA and SR treatment of T1N0M0 PTC.RFA is as effective as surgery for PTC in the danger triangle area in the short term, with faster recovery and fewer complications.Radiofrequency ablation has a clinical efficacy comparable to surgery in the treatment of papillary thyroid carcinoma in the danger triangle area in the short term with the advantages of faster recovery and fewer complications when compared with surgery.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Key Points: To compare the safety and efficiency of ultrasound-guided percutaneous radiofrequency ablation (RFA) and surgical resection (SR) for thyroid papillary carcinoma (PTC) in the danger triangle area.The clinical data of 298 patients who underwent either percutaneous RFA or SR for PTC in the thyroid danger triangle at our hospital between January 2018 and April 2020 were retrospectively analyzed. Propensity score matching is employed to regulate for confounding factors. All patients undergoing ablation were treated using a strategy that combined sufficient paratracheal fluid isolation with a low-power, short electrode. Disease progression was analyzed in patients with T1N0M0 PTC (T1a and T1b) employed in Kaplan‒Meier curves. Treatment parameters and the rates of local recurrence, distant metastasis, and complications are recorded and compared.Of 182 eligible patients who were included, 91 were in the RFA (age 44.84 ± 13.19; 71 females; 77 T1a) and 91 were in the SR (age 47.36 ± 11.05; 68 females; 69 T1a). The average treatment time, length of hospital stays, blood loss volume, and scar length are substantially less in the RFA than in the SR. Major complications as well as postoperative permanent recurrent laryngeal nerve injury and postoperative transient parathyroid dysfunction occurred only in the SR, with a substantial distinction between the two groups (p < 0.05). There is no substantial distinction in the disease progression between RFA and SR treatment of T1N0M0 PTC.RFA is as effective as surgery for PTC in the danger triangle area in the short term, with faster recovery and fewer complications.Radiofrequency ablation has a clinical efficacy comparable to surgery in the treatment of papillary thyroid carcinoma in the danger triangle area in the short term with the advantages of faster recovery and fewer complications when compared with surgery.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle.Use of radiofrequency ablation (RFA) in the thyroid danger triangle is still controversial.RFA and surgery groups showed no difference in disease progressions, and no major complications occurred with RFA.Radiofrequency ablation offers a new option for papillary thyroid carcinoma patients in the danger triangle. [ABSTRACT FROM AUTHOR]

Abstract: Production conditions of ZrB2, Zr and B condensed phases in the chemical vapor deposition process of ZrCl4–BCl3–H2 precursors have been investigated in details based on the thermodynamic analyses using the FactSage code and 41 species being involved from its embedded database. The production of the condensed phases has been examined as a function of the injected reactant ratios of ZrCl4/(ZrCl4 +BCl3) and H2/(ZrCl4 +BCl3), temperature and pressure. The results show that the condensed phase composition is quite sensitive to the reactant ratios and to the temperature whereas it is insensitive to the pressure. The ideal conditions for the deposition of ZrB2 are as follows: temperature ranging from 1050 to 1550K, ratios of ZrCl4/BCl3 of 1/2 and of H2/(ZrCl4 +BCl3) in the range of 10–1010, and pressures lower than 10.1kPa. The production of zirconium form in the region of H2/(ZrCl4 +BCl3) from 103 to 1014 with ZrCl4/BCl3 ratio higher than 1/2 and free boron appears in the ratios of H2/(ZrCl4 +BCl3) from 10−2 to 105 with ZrCl4/BCl3 ratio lower than 1/2. The deposition of single-phase ZrB2 and the co-deposition of ZrB2 with Zr or ZrB2 with B would be easily controlled by changing the ratios of ZrCl4/BCl3 and H2/(ZrCl4 +BCl3). In addition, the concentration distribution of precursors and gaseous species in the system was investigated. The results in this work are consistent with the available experimental and theoretical ones, and will be helpful for further experimental investigation of different deposition conditions with respect to the ratio of the injected reactants, pressure and temperature. [Copyright &y& Elsevier]

A fully integrated 100 kHz X-ray charge coupled device (CCD) readout application specific integrated circuit (ASIC) employing delta sigma (\Delta \Sigma ) digitization is presented. To achieve high linearity with small chip size and low power consumption, the correlated double sampling (CDS) is realized by the \Sigma \Delta{\rm ADC} instead of the analog front end (AFE) as in conventional CCD readout circuits. Besides, the proposed decimation filter features simple structure and eases the integration. The chip is fabricated in 0.35\ \upmu\hbox{m}$ CMOS technology and the measured integral nonlinearity (INL) throughout the input dynamic range of ASIC is 0.055% with 35.1 \pm 0.3\ \upmu\V input referred noise. A CCD detection system is built and tested with the sensitivity of CCD being 4\ \upmu\V/\e^-. The integration test results show that the readout noise is 11.8\ \e^ - at 100 kHz readout pixel rate and the achieved energy spectrum resolution is 168\ \eV \pm 4.7\ \eV (Full Width at Half Maximum: FWHM) at 5.9 keV. [ABSTRACT FROM PUBLISHER]

The paper presents the investigation of microstructures and tensile damage evolution of plain weave SiC fibre reinforced SiC matrix (SiC/SiC) composites using X-ray computed tomography (CT). A miniature high-precision in situ X-ray CT test fixture has been developed to conduct micro X-ray CT in-situ tensile tests. Through the image reconstruction of the CT data, the actual microstructures and the damage evolution of the material under six successive loading levels have been revealed precisely. Deep-learning-based image segmentation has been employed to recognise material damages, including transverse matrix cracking, longitudinal matrix cracking, and fibre pull-outs. Three-dimensional rendering models of these damages have been created to quantify the damage initiation and evolution. Both transverse and longitudinal matrix cracking initiates and propagates gradually at the intermediate loading level, but rapidly at the high loading level. The volume fraction of longitudinal matrix cracks is much larger than that of its transverse counterpart. It indicates that the longitudinal matrix cracking is much severer damage than transverse tracking. The lengths of fibre pull-outs at the fracture surface of fibre tows are in a broad range and on average they are in the order of a hundred microns. [ABSTRACT FROM AUTHOR]

Non-invasive, closed-loop brain modulation offers an accessible and cost-effective means of evaluating and modulating one's mental and physical well-being, such as Parkinson's disease, epilepsy, and sleep disorders. However, wearable EEG systems pose significant challenges for the analog front-end (AFE) circuits in view of µV-level EEG signals of interest, multiple sources of interference, and ill-defined skin contact. This paper presents a direct-digitization AFE tailored for dry-electrode scalp EEG recording, characterized by wide input dynamic range (DR) and high input impedance. The AFE utilizes a second-order 5-bit delta-delta sigma (Δ-ΔΣ) ADC to shape DC electrode offset (DEO) and low-frequency disturbances while retaining high accuracy. A non-inverting pseudo-differential instrumentation amplifier (IA) embedded in the ADC ensures high input impedance (Z in ) and common-mode rejection ratio (CMRR). Fabricated in a standard 0.18-μm CMOS process, the AFE delivers 700-mV pp input signal range, 95.3-dB DR, 87-dB SNDR, and 800-MΩ input impedance at 50 Hz while consuming 88.4µW from a 1.2 V supply. The benefits of high DR and high input impedance have been validated by dry-electrode EEG measurement.

This article describes a power-efficient, high dynamic range (DR) incremental ADC (IADC) for wearable biopotential signals recording, where DC and low-frequency disturbances such as electrode offset, 50/60 Hz interference and motion artifact must be tolerated. To achieve a wide DR, the IADC performs a three-step conversion by combining zoom-SAR and extended counting (EC) on top of a second-order incremental delta-sigma modulator (ΔΣM). The hybrid architecture notably reduces the oversampling ratio (OSR) with respect to conventional incremental ΔΣMs, while using the EC further improves the Signal-to-Noise-and-Distortion Ratio (SNDR) by 7.4 to 25.6 dB. Fabricated in a 0.18-μm CMOS technology, the IADC achieves 107.6-dB DR, 104.9-dB peak SNR, and 99.3-dB peak SNDR at 2 kS/s while dissipating 130 μW from 1.8-V (analog) / 1.2-V (digital) supply. This translates to a highly competitive FoM DR of 176.5 dB. The high-DR IADC reduces the gain of the preceding instrumentation amplifier (IA) such that significant DC and low-frequency disturbances can be tolerated. The advantages of high DR have been demonstrated by wearable Electrocardiography (ECG) and Electroencephalography (EEG) recordings under motion artifact.

Objectives: To evaluate the feasibility, efficacy, and safety of radiofrequency ablation (RFA) for solitary T1N0M0 papillary thyroid carcinoma (PTC) in the danger triangle area., Methods: 94 participants (mean age 44.45 ± 13.08; 73 females) with solitary T1N0M0 PTC in the danger triangle area who underwent percutaneous RFA at the hospital from January 2018 to April 2020 were retrospectively analyzed. Key ablation procedures included sufficient paratracheal fluid isolation, low-power, and short active tip (5 mm working electrode). Tumor size changes at different time points after RFA, technical success rates, tumor disappearance, disease progression, and complications were recorded and compared., Results: Contrast-enhanced ultrasonography revealed that complete tumor ablation was performed with a 100% success rate in these patients. Post-ablation, the maximum diameter and volume of the ablation zone increased at the first and third month ( p  < 0.001), followed by a gradual decrease in size, without significant difference by the 6th month. The tumor disappearance rate was 76.59% (72/94), with higher rates in the T1a group compared to the T1b group (80% [64/80] VS57.1% [8/14], p  < 0.001). There were no local recurrences. The incidence of new lesions and LNM was 3.2% (3/94), limited to the T1a subgroup. Further ablation was successfully applied to all new lesions and LMN. Mild voice changes were the only complication, with a rate of 3.2% (3/94), resolved within 4 months after RFA., Conclusions: Sufficient paratracheal fluid isolation combined with a low-power, short active tip radiofrequency ablation strategy is a safe and effective method for treating solitary T1N0M0 PTC in the danger triangle area.

Assessing blood flow, respiration patterns, and body composition with wearable and noninvasive bio-impedance (BioZ) sensors has distinctive advantages over the conventional clinical practice. The merits of BioZ sensors derive from having long-term monitoring capability and improved user friendliness. These open up the way to build medical grade wearable devices for chronic conditions. Low power, high precision BioZ sensor interface IC is the heart of such devices, it also determines the signal integrity of the overall system. Nevertheless, electrical design challenges from both circuit and system perspective still need to be addressed. This paper reviews the pioneering BioZ interface ICs and systems, and proposes major electrical specifications for wearable BioZ sensors. System design methodologies and circuit optimization techniques are summarized as guidelines to develop the next generation BioZ interface electronics.