Search

Objective Cutterhead torque is a crucial parameter that characterizes the safety of shield tunneling and the operating status of equipment. To address the difficulties in cutterhead torque prediction and excavation parameters timely correction, an advanced prediction method for shield tunneling cutterhead torque based on WaveNet network is proposed. Method The preprocessing method for working condition data is introduced, and the basic structure and construction method of the initial static model based on WaveNet network are proposed. A training set is constructed by extracting historical data of shield construction monitoring within the initial 50 m tunneling distance, and advanced prediction of the cutterhead torque is made after five construction steps based on the shield construction monitoring data of the previous 20 construction steps. With the increase of shield excavation distance, the model is retrained and updated every five construction steps using newly generated data set, thus a long-term dynamic model for cutterhead torque advanced prediction is proposed. Taking the left-line data of the Yufuhe Sta.-Wangfuzhuang Sta. shield tunnel interval of Jinan Rail Transit Line 1 as example, the prediction effect of cutterhead torque is analyzed and verified. Result & Conclusion The cutterhead torque values by advanced prediction for the first 50 m tunneling distance show a basic consistency with the changing trend of actual values, with an average relative error of 10.07%. The initial static model exhibits relatively high prediction accuracy. As the tunneling distance increases, the relative error of the initial static model increases from 10% to about 30%, while that of the continuously updated long-term dynamic model remains stable at around 10%. The update time of the long-term dynamic model is generally distributed between 1 and 6 seconds, with an average time consumption of 3.92 s, meeting the requirement for efficient dynamic model updates.

TGF-β1 has long been considered as a key mediator in diabetic kidney disease (DKD) but anti-TGF-β1 treatment fails clinically, suggesting a diverse role for TGF-β1 in DKD. In the present study, we examined a novel hypothesis that latent TGF-β1 may be protective in DKD mice overexpressing human latent TGF-β1. Streptozotocin-induced Type 1 diabetes was induced in latent TGF-β1 transgenic (Tg) and wild-type (WT) mice. Surprisingly, compared to WT diabetic mice, mice overexpressing latent TGF-β1 were protected from the development of DKD as demonstrated by lowing microalbuminuria and inhibiting renal fibrosis and inflammation, although blood glucose levels were not altered. Mechanistically, the renal protective effects of latent TGF-β1 on DKD were associated with inactivation of both TGF-β/Smad and nuclear factor-κB (NF-κB) signaling pathways. These protective effects were associated with the prevention of renal Smad7 from the Arkadia-induced ubiquitin proteasomal degradation in the diabetic kidney, suggesting protection of renal Smad7 from Arkadia-mediated degradation may be a key mechanism through which latent TGF-β1 inhibits DKD. This was further confirmed in vitro in mesangial cells that knockdown of Arkadia failed but overexpression of Arkadia reversed the protective effects of latent TGF-β1 on high glucose-treated mesangial cells. Latent TGF-β1 may protect kidneys from TGF-β1/Smad3-mediated renal fibrosis and NF-κB-driven renal inflammation in diabetes through inhibiting Arkadia-mediated Smad7 ubiquitin degradation.

Objective To investigate the clinical and imaging features of the characteristic "heart appearance" isolated cerebral infarction involving bilateral pons-medulla oblongata. Methods The clinical and imaging data of 2 patients with bilateral pons-medulla oblongata "heart appearance" isolated infarction treated in our hospital from May 2019 to February 2020 were retrospectively analyzed. The published domestic and foreign literature of patients with this disease collected in PubMed, Web of Science, CNKI, WanFang and other databases in recent 10 years were also searched by computer, and the literature was subsequently reviewed and analyzed. Results The course of the disease in both patients was progressive, with clinical manifestations of bulbar palsy, sensory disturbance, progressive quadriplegia, and respiratory involvement. Brain magnetic resonance imaging (MRI) showed a typical "heart appearance" isolated infarction in the medial medulla or pons. Digital subtraction angiography (DSA) revealed vertebrobasilar atherosclerosis in case 1 and vertebrobasilar atherosclerosis, stenosis, and occlusion in case 2. A total of 29 patients were contained in 24 pieces of literature, including 21 cases of medulla oblongata infarction and 8 cases of pontine infarction, all with "heart appearance". Thereby a total of 31 patients, including 28 males, and 3 females, were reported by our center and the literature, with onset age of 32~87 (60.3±12.1) years. Among them, there were 29 cases of bulbar palsy symptoms (29/31, 93.55%), 23 of sensory impairment (23/31, 74.19%), 31 of quadriplegia (100%), 29 with progressive disease course (29/31, 93.55%), 23 with respiratory involvement (23/31, 74.19%), 24 with poor prognosis (24/29, 82.76%), and death in 6 cases (6/29, 20.69%). Of the 29 patients examined by MRA, CTA or DSA, 7 had no obvious abnormality or only atherosclerosis in the vertebrobasilar artery (7/29, 24.14%), 11 had vertebrobasilar stenosis or dysplasia (11/29, 37.93%), and the remaining 11 showed vertebrobasilar artery occlusion (11/29, 37.93%). Conclusion Isolated "heart appearance" infarction of the bilateral medial pons-medulla oblongata is clinically rare and has special morphological features on brain MRI. The etiology of such patients is mainly vertebrobasilar atherosclerosis, stenosis or occlusion. The course of the disease is often progressive, quadriplegia, and involves breathing, with critical condition, which is prone to misdiagnosis and missed diagnosis. Brain MRI and DSA examination are suggested to be performed as soon as possible to facilitate early diagnosis and treatment to improve the prognosis.

Emerging millimeter‐wave wireless communication systems require high‐performance radio frequency switches to support advanced functionality such as frequency agility, circuit reconfigurability, and beamforming. Ferroelectric (FE)‐gated AlGaN/GaN high‐electron‐mobility transistors (HEMTs) (FeHEMTs) are developed and demonstrated as a technology option for this important role. AlGaN/GaN HEMT heterostructures grown by metal‐organic chemical vapor deposition are augmented with a FE gate stack comprising atomic layer deposition‐grown HfZrO2. In addition, highly doped regrown source and drain Ohmic contacts are integrated into an improved fabrication process flow. This improved process leads to contact resistances of 0.105 Ω mm and a reduction in switch on‐resistance as compared to prior reports, as well as drain current densities of 1 A mm−1 and measured ft = 54 GHz for gate lengths of 0.1 μm. The improved contact and gate length scaling makes FeHEMTs a promising candidate for mm‐wave switch applications achieving a reported switch figure of merit of fCO = 1.55 THz. [ABSTRACT FROM AUTHOR]