40 research outputs found

    Generic Scarring for Minimal Hypersurfaces in Manifolds Thick at Infinity with a Thin Foliation at Infinity

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    We show generic scarring phenomenon for minimal hypersurfaces in a class of complete non-compact manifolds. In particular, we prove that for any metric gg in a C∞C^{\infty}-generic subset of the family of complete metrics which are thick at infinity with a thin foliation at infinity on a fixed Mn+1M^{n+1} of dimension 3≤(n+1)≤73 \leq (n + 1) \leq 7, to any connected, closed, embedded, 22-sided, stable minimal hypersurface S⊂(M,g)S \subset (M, g), there exists a sequence of closed, embedded, minimal hypersurfaces {Σk}\{\Sigma_{k}\} scarring along SS, in the sense that the area of Σk\Sigma_{k} diverges to infinity, and when properly renormalized, Σk\Sigma_{k} converges to SS as varifolds.Comment: Some corrections added and typos fixed. arXiv admin note: text overlap with arXiv:2006.03038 by other author

    Introducing Expertise Logic into Graph Representation Learning from A Causal Perspective

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    Benefiting from the injection of human prior knowledge, graphs, as derived discrete data, are semantically dense so that models can efficiently learn the semantic information from such data. Accordingly, graph neural networks (GNNs) indeed achieve impressive success in various fields. Revisiting the GNN learning paradigms, we discover that the relationship between human expertise and the knowledge modeled by GNNs still confuses researchers. To this end, we introduce motivating experiments and derive an empirical observation that the human expertise is gradually learned by the GNNs in general domains. By further observing the ramifications of introducing expertise logic into graph representation learning, we conclude that leading the GNNs to learn human expertise can improve the model performance. By exploring the intrinsic mechanism behind such observations, we elaborate the Structural Causal Model for the graph representation learning paradigm. Following the theoretical guidance, we innovatively introduce the auxiliary causal logic learning paradigm to improve the model to learn the expertise logic causally related to the graph representation learning task. In practice, the counterfactual technique is further performed to tackle the insufficient training issue during optimization. Plentiful experiments on the crafted and real-world domains support the consistent effectiveness of the proposed method

    The Use of Intraosseous Needles for Injection of Contrast Media for Computed Tomographic Angiography of the Thoracic Aorta

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    Background The objective of this study is to evaluate the safety and quality of computed tomographic angiography of the thoracic aorta (CTA-TA) exams performed using intraosseous needle intravenous access (ION-IVA) for contrast media injection (CMI). Methods All CTA-TA exams at the study institution performed between 1/1/2013 and 8/14/2015 were reviewed retrospectively to identify those exams which had been performed using ION-IVA (ION-exams). ION-exams were then analyzed to determine aortic attenuation and contrast-to-noise ratio (CNR). Linear regression was used to determine how injection rate and other variables affected image quality for ION-exams. Patient electronic medical records were reviewed to identify any adverse events related to CTA-TA or ION-IVA. Results 17 (∼0.2%) of 7401 exams were ION-exams. ION-exam CMI rates varied between 2.5 and 4 ml/s. Mean attenuation was 312 HU (SD 88 HU) and mean CNR was 25 (SD 9.9). A strong positive linear association between attenuation and injection rate was found. No immediate or delayed complications related to the ION-exams, or intraosseous needle use in general, occurred. Conclusion For CTA-TA, ION-IVA appears to be a safe and effective route for CMI at rates up to 4 ml/s

    Research and Experiments on a Unipolar Capacitive Voltage Sensor

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    Voltage sensors are an important part of the electric system. In service, traditional voltage sensors need to directly contact a high-voltage charged body. Sensors involve a large volume, complex insulation structures, and high design costs. Typically an iron core structure is adopted. As a result, ferromagnetic resonance can occur easily during practical application. Moreover, owing to the multilevel capacitor divider, the sensor cannot reflect the changes of measured voltage in time. Based on the electric field coupling principle, this paper designs a new voltage sensor; the unipolar structure design solves many problems of traditional voltage sensors like the great insulation design difficulty and high costs caused by grounding electrodes. A differential signal input structure is adopted for the detection circuit, which effectively restrains the influence of the common-mode interference signal. Through sensor modeling, simulation and calculations, the structural design of the sensor electrode was optimized, miniaturization of the sensor was realized, the voltage division ratio of the sensor was enhanced, and the phase difference of sensor measurement was weakened. The voltage sensor is applied to a single-phase voltage class line of 10 kV for testing. According to the test results, the designed sensor is able to meet the requirements of accurate and real-time measurement for voltage of the charged conductor as well as to provide a new method for electricity larceny prevention and on-line monitoring of the power grid in an electric system. Therefore, it can satisfy the development demands of the smart power grid

    Research and Experiments on a Unipolar Capacitive Voltage Sensor

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    Voltage sensors are an important part of the electric system. In service, traditional voltage sensors need to directly contact a high-voltage charged body. Sensors involve a large volume, complex insulation structures, and high design costs. Typically an iron core structure is adopted. As a result, ferromagnetic resonance can occur easily during practical application. Moreover, owing to the multilevel capacitor divider, the sensor cannot reflect the changes of measured voltage in time. Based on the electric field coupling principle, this paper designs a new voltage sensor; the unipolar structure design solves many problems of traditional voltage sensors like the great insulation design difficulty and high costs caused by grounding electrodes. A differential signal input structure is adopted for the detection circuit, which effectively restrains the influence of the common-mode interference signal. Through sensor modeling, simulation and calculations, the structural design of the sensor electrode was optimized, miniaturization of the sensor was realized, the voltage division ratio of the sensor was enhanced, and the phase difference of sensor measurement was weakened. The voltage sensor is applied to a single-phase voltage class line of 10 kV for testing. According to the test results, the designed sensor is able to meet the requirements of accurate and real-time measurement for voltage of the charged conductor as well as to provide a new method for electricity larceny prevention and on-line monitoring of the power grid in an electric system. Therefore, it can satisfy the development demands of the smart power grid

    Modified minimally invasive laparoscopic peritoneal dialysis catheter insertion with internal fixation

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    AbstractBackground Laparoscopic technique is widely used in peritoneal dialysis (PD) catheter placement. We developed a modified minimally invasive laparoscopic PD catheter (PDC) insertion with internal fixation and evaluated the early results by observing the intraoperative and postoperative conditions of the novel technique with those of conventional open surgery.Methods Retrospective research was performed on 59 patients who underwent PDC insertion from June 2019 to January 2022, including 23 patients who received open surgery and 36 patients who received modified minimally invasive laparoscopic surgery. Information such as preoperative conditions, operation time, incision length, incidence of intraoperative complications, time from operation to starting PD, time from operation to discharge, and incidence of catheter-related complications were collected and analyzed.Results The incision length, intraoperative blood loss, catheter migration rates and the total incidence of complications 6 months after operation in the laparoscopic group were lower than those in the conventional group. There were no statistically significant differences between the two groups in operation time, time from operation to starting PD, time from operation to discharge and the incidence of catheter blockage, leakage, exit-site infection, peritoneal dialysis associated peritonitis and hernia.Conclusions Modified minimally invasive laparoscopic PDC insertion and internal fixation method achieved direct vision and reliable fixation of the catheter, significantly reduced incision length and blood loss. The incidence of catheter migration was significantly lower than that of open surgery. Our primary findings reveal that modified minimally invasive laparoscopic PDC insertion with internal fixation is safe, effective and beneficial for PD patients

    Simulation Study Low Voltage Power Line Carrier Communication in Noisy Environments

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    Studies have shown that there are a lot of low- voltage power line is one of the main obstacles to strong noise limit for data transmission quality. Power line noise can be divided into steady background noise, narrowband interference noise, sudden impulse noise and periodic noise. Background noise is distributed throughout the communication band, low-voltage power line up white Gaussian noise 22dB [133 or more. Sudden noise is generated by the random access or disconnect electrical equipment produced. Studies have shown that pulse interference effects on the quality of the low voltage power line carrier communication maximum. Literature statistics, intensity pulsed interference up 40dBuv

    Local Consolidative Therapy for Oligometastatic Non-Small Cell Lung Cancer

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    In the last 20 years, significant strides have been made in our understanding of the biological mechanisms driving disease pathogenesis in metastatic non-small cell lung cancer (NSCLC). Notably, the development and application of predictive biomarkers as well as refined treatment regimens in the form of chemoimmunotherapy and novel targeted agents have led to substantial improvements in survival. Parallel to these remarkable advancements in modern systemic therapy has been a growing recognition of “oligometastatic disease” as a distinct clinical entity—defined by the presence of a controlled primary tumor and ≤5 sites of metastatic disease amenable to local consolidative therapy (LAT), with surgery or stereotactic ablative body radiotherapy (SABR). To date, three randomized studies have provided clinical evidence supporting the use of LAT/SABR in the treatment of oligometastatic NSCLC. In this review, we summarize clinical evidence from these landmark studies and highlight ongoing trials evaluating the use of LAT/SABR in a variety of clinical contexts along the oligometastatic disease spectrum. We discuss important implications and caveats of the available data, including considerations surrounding patient selection and application in routine clinical practice. We conclude by offering potential avenues for further investigation in the oligometastatic disease space

    Research on Low Voltage Power Line Carrier Communication Simulation Software

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