Mode of anesthesia for cesarean delivery with pernicious placenta previa — a retrospective study

Objectives: Anesthesia for cesarean delivery in parturients diagnosed with pernicious placenta previa remains controversial. This study aimed to review pernicious placenta previa cases to evaluate anesthetic management strategies. Material and methods: This retrospective analysis included patients who underwent cesarean delivery (CD) for pernicious placenta previa at the Affiliated Hospital of Zunyi Medical University between December 1, 2012 and November 31, 2017. Patient demographic data, obstetric characteristics, anesthetic management, and maternal outcomes were extracted from the hospital’s computerized database. Results: In all, 61 consecutive cases of pernicious placenta previa were identified among 9512 cesarean deliveries. General anesthesia was performed on 27 of the 61 patients (44.3%). Among GA group, 16 (59.3%) had placenta accreta, 8 of whom required cesarean hysterectomy. Also, 13 of the 27 (48.1%) GA patients required transfer to the intensive care unit. The other 34 patients (55.7%) were given regional anesthesia, 9 of whom were converted to general anesthesia due to excessive bleeding and prolonged operation times. Statistical results indicated that regional anesthesia was associated with a significantly shorter operation time, less perioperative blood loss, fewer intraoperative red blood cell transfusions, and a lower incidence of complications. Conclusions: Anesthetic management is important for parturients with pernicious placenta previa. Although regional anesthesia was our preferred method for these patients, general anesthesia is safe for patients with pernicious placenta previa who experience massive blood loss and prolonged operation times

Polarization-entangled photon pair sources based on spontaneous four wave mixing assisted by polarization mode dispersion

Photonic-based qubits and integrated photonic circuits have enabled demonstrations of quantum information processing (QIP) that promises to transform the way in which we compute and communicate. To that end, sources of polarization-entangled photon pair states are an important enabling technology, especially for polarization-based protocols. However, such states are difficult to prepare in an integrated photonic circuit. Scalable semiconductor sources typically rely on nonlinear optical effects where polarization mode dispersion (PMD) degrades entanglement. Here, we directly generate polarization-entangled states in an AlGaAs waveguide, aided by the PMD and without any compensation steps. We perform quantum state tomography and report a raw concurrence as high as 0.91$\pm$0.01 observed in the 1100-nm-wide waveguide. The scheme allows direct Bell state generation with an observed maximum fidelity of 0.90$\pm$0.01 from the 800-nm-wide waveguide. Our demonstration paves the way for sources that allow for the implementation of polarization-encoded protocols in large-scale quantum photonic circuits

Towards a General Framework for Continual Learning with Pre-training

In this work, we present a general framework for continual learning of sequentially arrived tasks with the use of pre-training, which has emerged as a promising direction for artificial intelligence systems to accommodate real-world dynamics. From a theoretical perspective, we decompose its objective into three hierarchical components, including within-task prediction, task-identity inference, and task-adaptive prediction. Then we propose an innovative approach to explicitly optimize these components with parameter-efficient fine-tuning (PEFT) techniques and representation statistics. We empirically demonstrate the superiority and generality of our approach in downstream continual learning, and further explore the applicability of PEFT techniques in upstream continual learning. We also discuss the biological basis of the proposed framework with recent advances in neuroscience.Comment: This is a generalized version of our HiDe-Prompt and will be presented in the IMOL workshop in NeurIPS 2023. arXiv admin note: text overlap with arXiv:2310.0723

A novel type of hybrid ultrasonic motor using longitudinal and torsional vibration modes with side panels

A novel type of hybrid ultrasonic motor using longitudinal and torsional vibration modes is presented, which has four side panels uniformly distributed along the circumference of the stator cylinder. There is rectangle piezoelectric ceramics (PZTs) based on d31 effect bonded on both sides of each side panels, which can be used to convert the first bending vibration mode of the side panels into the second torsional vibration mode of the stator when the exciting voltage is applied. Meanwhile, there are rectangle PZTs based on d31 effect bonded on the surfaces of the stator cylinder between every two side panels, which can be used to excite the first longitudinal vibration mode of the stator. The simulation results using finite element method (FEM) software Workbench reveals the suitable polarization arrangement of PZTs and the final designed structure of the motor. The appearance size of the prototype is 28.2 mm×28.2 mm×68 mm, while the outer diameter of the stator cylinder is 20 mm. The major vibration and mechanical characteristics of the prototype have been measured. The working frequency of the prototype measured in experiment is around 43.12 kHz, which is consistent with the numerical results. When operating voltage of 350 Vp-p is applied, the no-load speed of the prototype is 103 rpm and the stalling torque is 48 mN·m