Abstract The objective of this study was to investigate the clinical features of Kimura's disease in the head and neck region and to compare the local recurrence rate between three therapies used for ...the treatment of this disease. The clinicopathological information of 46 hospitalized patients suffering from Kimura's disease in the head and neck region over a 10-year period was reviewed retrospectively. All lesions were clinically observed in the head and neck region. These 46 patients underwent a total of 58 treatments; nine patients underwent multiple treatments due to local recurrence. Of the 58 treatments, 32 involved surgical excision alone, 24 involved surgical excision and postoperative low-dose radiotherapy (20–40 Gy), one was a combination of ultrasound-guided core needle biopsy and radiotherapy, and one was a combination of incisional biopsy and subsequent radiotherapy. During the follow-up period, nine patients suffered 16 local recurrences. The recurrence rate of surgical excision combined with low-dose radiotherapy was much lower than that of surgical excision alone or radiotherapy alone (both P < 0.05). It is concluded that Kimura's disease is a benign condition with a good prognosis, and surgical excision combined with postoperative low-dose radiotherapy is associated with the lowest local recurrence rate in the treatment of this disease.
Due to loss of tactile feedback the assessment of tumor margins during robotic surgery is based only on visual inspection, which is neither significantly sensitive nor specific. Here we demonstrate ...time-resolved fluorescence spectroscopy (TRFS) as a novel technique to complement the visual inspection of oral cancers during transoral robotic surgery (TORS) in real-time and without the need for exogenous contrast agents. TRFS enables identification of cancerous tissue by its distinct autofluorescence signature that is associated with the alteration of tissue structure and biochemical profile. A prototype TRFS instrument was integrated synergistically with the da Vinci Surgical robot and the combined system was validated in swine and human patients. Label-free and real-time assessment and visualization of tissue biochemical features during robotic surgery procedure, as demonstrated here, not only has the potential to improve the intraoperative decision making during TORS but also other robotic procedures without modification of conventional clinical protocols.
In this article, a 10-MHz switching power converter is introduced to satisfy stringent requirements on 5G mobile Internet-of-Things (IoTs) power delivery. To achieve nanosecond power flipping, the ...converter utilizes a double adaptive bound (DAB) hysteretic control to improve load transient performance. A synchronized dc resistance offset cancellation scheme is naturally embedded to enhance load regulation accuracy while retaining fixed frequency operation. The controller circuit can be easily reconfigured to achieve a power scalable operation, which facilitates the converter with adaptive system power delivery capability to achieve high efficiency over a wide power range. An integrated circuit prototype is fabricated using a 180-nm CMOS process with an active die area of 0.175 mm 2 , achieving a peak power density of 14.3 W/mm 2 . In response to 1 A/3 ns load increase/decrease between zero and maximum power, it achieves 1% settling time of 247 ns/387 ns with 31 mV/60 mV voltage droop, respectively. With a nominal switching frequency of 10 MHz, the switching frequency variations are controlled below 0.1% despite of the use of a hysteretic control. And the output regulation accuracy is improved with only 0.3% error. Thanks to the proposed power scalable reconfiguration and adaptive power delivery, the converter achieves above 80% efficiency over 99.9% of 2.5-W full power range with a peak efficiency of 91%.
To meet stringent electromagnetic interference (EMI) requirements in modern integrated systems, this article presents a gallium nitride (GaN)-based switching power converter operating at 8.3 MHz. It ...employs a Markov continuous random spread-spectrum modulation (RSSM) technique to spread EMI spectra almost uniformly, and thus attenuate EMI level effectively. On the other hand, a one-cycle ON-time rebalancing scheme is designed to stabilize the duty-ratio of the converter even if the switching frequency changes randomly, suppressing the output voltage jittering without influencing the EMI reduction by RSSM. A prototype was designed and fabricated using a 0.18-μm HV CMOS process. With ±10% modulation range of a nominal switching frequency of 8.3 MHz, peak EMI is reduced from 66 to 35 dBμV at the fundamental frequency and from 62 to 27 dBμV at the third-order harmonic. In the meantime, the RSSM-induced output voltage jittering is suppressed from 240 to below 10 mV. The converter achieves above 60% efficiency over 96.6% of 7.5-W full power range, with a peak efficiency of 86.8% at 6.25 W.
In mobile applications, power density highly affects mobility, cost, form factor, and battery time. To improve power density, high switching frequency operation is highly desirable for a power ...converter. However, with high switching frequency, switching power loss increases significantly, compromising efficiency and battery time. This article presents an on-chip 3-level DC-DC converter, using all NMOS devices as power switches, which reduces switching power loss and silicon cost. To facilitate the all-NMOS power stage operation and enhance the robustness to input supply variation, a 3-switch boost-strap gate driver is designed. Meanwhile, an interception coupling dead-time (ICDT) control is introduced to minimize dead-time related power loss. An integrated circuit prototype was fabricated using a 0.35 μm CMOS process. Robustly working with a variable input voltage from 3 to 6 V, it regulates a programmable power output from 0.4 to 1.6 V, with a maximum power efficiency of 85.5% over a full power range of 800 mW and a maximum power density of 1.07 W/mm 2 . Thanks to the ICDT control, it achieves a 0.5 ns dead-time over a full-load range of 500 mA.
The trillions of microbes that make up the gut microbiome are an important contributor to health and disease. With respect to xenobiotics, particularly orally administered compounds, the gut ...microbiome interacts directly with drugs to break them down into metabolic products. In addition, microbial products such as bile acids interact with nuclear receptors on host drug-metabolizing enzyme machinery, thus indirectly influencing drug disposition and pharmacokinetics. Gut microbes also influence drugs that undergo enterohepatic recycling by reversing host enzyme metabolic processes and increasing exposure to toxic metabolites as exemplified by the chemotherapy agent irinotecan and non-steroidal anti-inflammatory drugs. Recent data with immune checkpoint inhibitors demonstrate the impact of the gut microbiome on drug pharmacodynamics. We summarize the clinical importance of gut microbe interaction with digoxin, irinotecan, immune checkpoint inhibitors, levodopa, and non-steroidal anti-inflammatory drugs. Understanding the complex interactions of the gut microbiome with xenobiotics is challenging; and highly sensitive methods such as untargeted metabolomics with molecular networking along with other in silico methods and animal and human in vivo studies will uncover mechanisms and pathways. Incorporating the contribution of the gut microbiome to drug disposition, pharmacokinetics, and pharmacodynamics is vital in this era of precision medicine.
Targeting on electromagnetic interference (EMI) regulation and ringing suppression issues in automotive applications, this paper presents a gallium nitride (GaN)-based dc-dc converter operating at 10 ...MHz. A spurious noise compression technique compresses and re-distributes spurious switching noise within a defined frequency sideband, achieving EMI noise reduction at main switching frequency and its harmonics. Meanwhile, a tri-slope gate driver is designed to control voltage and current slew rates of GaN switches for effective ringing suppression, which is adaptive to load and input voltage changes. Tailored for high switching frequency and high-efficiency operation, the dynamic level shifters achieve about 0.8-ns propagation delay and near-zero quiescent current. Fabricated in a 0.35-μm Bipolar-CMOS-DMOS process, the converter accomplishes an EMI noise reduction of 40.5 dBμV and suppresses VSW ringing by 79.3%. The converter retains above 60% efficiency over 96.6% of its 6-W power range, with a peak efficiency of 85.5% at 1.5-W load.
In the present study, fluid flow and heat transfer in microchannel heat sinks with different inlet/outlet locations (I, C and Z-type), header shapes (triangular, trapezoidal and rectangular) and ...microchannel cross-section shapes (the conventional rectangular microchannel, the microchannel with offset fan-shaped reentrant cavities and the microchannel with triangular reentrant cavities) are numerically studied with computational domain including the entire microchannel heat sink. Detailed three-dimensional numerical simulations are useful in identifying the optimal geometric parameters that provide better heat transfer and flow distribution in a microchannel heat sink. Results highlight that flow velocity uniformity is comparatively better for I-type and poor for Z-type. The flow distribution is found to be symmetrical for I-type. It is seen from the header shapes analysis that the rectangular header shapes provides better flow velocity uniformity than the trapezoidal and triangular headers. The fluid flow mechanism can be attributed to the interaction of the branching of fluid and the friction offered by the walls of the header. Effects of microchannel cross-section shapes emphasize that the microchannel with offset fan-shaped reentrant cavities and the microchannel with triangular reentrant cavities of the heat sinks enhance the heat transfer compared to the conventional rectangular microchannel. The heat transfer mechanism can be attributed to the jetting and throttling effect, the additional flow disturbance near the wall of the reentrant cavities and the form drag of the reentrant cavities. The heat sink C has better heat transfer characteristic for qv=150ml/min and is able to prolong the life of the microelectronic devices.
•Sinusoidal wavy microchannels with secondary channels (SWSC) are designed and fabricated.•A complete high-speed measurement system are performed for flow boiling.•Flow boiling performance of SWSC ...are investigated and compared with the conventional rectangular microchannels (R).•Improvement in heat transfer performance are achieved by the SWSC microchannels.•Pressure drop and flow boiling instabilities are illustrated.
Sinusoidal wavy microchannels with secondary channels (SWSC) are developed to integrate advantages of the sinusoidal corrugated structure and the introduction of secondary channels in flow boiling enhancement. Flow boiling investigations of acetone are made with variation in the heat flux and mass flux range of 251–512 kg/(m2·s). The boiling curves, heat transfer coefficients, pressure drops and flow boiling instabilities are systematically investigated. The experimental results show that the SWSC microchannels can achieve better heat removal performance than the conventional rectangular microchannels (R). Besides, the premature ONB and delayed CHF can also be obtained. The increased density of bubble nucleation induced by the enlarged surface area and the liquid stored in the corner regions in the nucleate boiling dominated regime, as well as the continuously developing thin liquid film created by the introduction of secondary channels in the stable liquid film evaporation dominated regime are considered to be the main reasons for the notable enhancement in heat transfer. However, the SWSC microchannels suffer a higher pressure drop penalty. The pressure fluctuations and temperature fluctuations of the SWSC microchannels are also illustrated.
Abstract
Piscine orthoreovirus (PRV) causes heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon. During salmon production cycles, HSMI has predominantly been observed after ...seawater transfer. More recently, better surveillance and longitudinal studies have detected occurrences of PRV-1 in freshwater broodstock farms and hatcheries. However, very little is known about the viral kinetics of PRV-1 or disease development of HSMI during these pre-smolt stages. In this study, we conducted a long-term PRV-1 challenge experiment to examine the profile of viral load, infectiousness and/or clearance in Atlantic salmon during their development from fry to parr stage. Atlantic salmon fry (mean weight: 1.1 ± 0.19 g) were infected with PRV-1 (high virulent variant) via intraperitoneal (IP) injection. The viral load reached a peak at 2–4 weeks post-challenge (wpc) in heart and muscle tissues. The virus was detected at relatively high levels in whole blood, spleen, and head kidney tissues until 65 wpc. Heart and muscle lesions typical of HSMI were clearly observed at 6 and 8 wpc but then subsided afterwards resolving inflammation. Innate and adaptive immune responses were elicited during the early/acute phase but returned to basal levels during the persistent phase of infection. Despite achieving high viremia, PRV-1 infection failed to cause any mortality during the 65-week virus challenge period. Cohabitation of PRV-1 infected fish (10 and 31 wpc) with naïve Atlantic salmon fry resulted in very low or no infection. Moreover, repeated chasing stress exposures did not affect the viral load or shedding of PRV-1 at 26 and 44 wpc. The present findings provide knowledge about PRV-1 infection in juvenile salmon and highlight the importance of continued monitoring and management to prevent and mitigate the PRV-1 infection in freshwater facilities.
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