32 research outputs found
A high-precision bidirectional time-transfer system over a single fiber based on wavelength-division multiplexing and time-division multiplexing
In this paper, a high-precision bidirectional time-transfer system over a single fiber based on wavelength-division multiplexing and time-division multiplexing (SFWDM-TDM) is proposed, which combines the advantages of wavelength-division multiplexing and time-division multiplexing. It uses two dense wavelength-division channels to effectively suppress the problem of optical fiber reflection. At the same time, the time-division multiplexing method is used in combination with sampling and holding the time to complete the multi-user task. In hardware, we optimized the carrier processing and the high-precision time-delay control module of the SFWDM-TDM system to complete high-precision time-transfer equipment. In software and algorithm, the optical fiber time-interval measurement method and measurement times are optimized, and the SFWDM-TDM system reaches a synchronization accuracy of 8.9 ps at 1Â s. Finally, a real-time detection mechanism with self-recovery ability is added to the system. This lays the foundation for a reliable, long-distance, high-precision, and multi-user mode optical fiber time- and frequency-transfer network
Short-term outcomes of robot-assisted versus video-assisted thoracoscopic surgery for non-small cell lung cancer patients with neoadjuvant immunochemotherapy: a single-center retrospective study
BackgroundNeoadjuvant immunochemotherapy has been increasingly applied to treat non-small cell lung cancer (NSCLC). However, the comparison between robotic-assisted thoracoscopic surgery (RATS) and video-assisted thoracoscopic surgery (VATS) in the feasibility and oncological efficacy following neoadjuvant immunochemotherapy is scarce. This study aims to assess the superiorities of RATS over (VATS) concerning short-term outcomes in treating NSCLC patients with neoadjuvant immunochemotherapy.MethodsNSCLC patients receiving RATS or VATS lobectomy following neoadjuvant immunochemotherapy at Shanghai Chest Hospital from 2019 to 2022 were retrospectively identified. Baseline clinical characteristics, perioperative outcomes, and survival profiles were analyzed.ResultsForty-six NSCLC patients with neoadjuvant immunochemotherapy were included and divided into the RATS (n=15) and VATS (n=31) groups. The baseline clinical characteristics and induction-related adverse events were comparable between the two groups (all p>0.050). The 30-day mortality in the RATS and VATS groups were 0% and 3.23%, respectively (p=1.000). Patients undergoing RATS were associated with reduced surgical-related intensive unit care (ICU) stay than those receiving VATS (0.0 [0.0-0.0] vs. 0.0 [0.0-1.0] days, p=0.026). Moreover, RATS assessed more N1 LNs (6.27 ± 1.94 vs 4.90 ± 1.92, p=0.042) and LN stations (3.07 ± 1.03 vs 2.52 ± 0.57, p=0.038) compared with VATS. By comparison, no difference was found in surgical outcomes, pathological results, and postoperative complications between the RATS and VATS groups (all p>0.050). Finally, RATS and VATS achieved comparable one-year recurrence-free survival (82.96% vs. 85.23%, p=0.821) and the timing of central nervous system, LN, and bone recurrences (all p>0.050).ConclusionRATS is safe and feasible for NSCLC patients with neoadjuvant immunochemotherapy, reducing surgical-related ICU stay, assessing increased N1 LNs and stations, and achieving similar survival profiles to VATS
Investigating Driver Fatigue versus Alertness Using the Granger Causality Network
Driving fatigue has been identified as one of the main factors affecting drivers’ safety. The aim of this study was to analyze drivers’ different mental states, such as alertness and drowsiness, and find out a neurometric indicator able to detect drivers’ fatigue level in terms of brain networks. Twelve young, healthy subjects were recruited to take part in a driver fatigue experiment under different simulated driving conditions. The Electroencephalogram (EEG) signals of the subjects were recorded during the whole experiment and analyzed by using Granger-Causality-based brain effective networks. It was that the topology of the brain networks and the brain’s ability to integrate information changed when subjects shifted from the alert to the drowsy stage. In particular, there was a significant difference in terms of strength of Granger causality (GC) in the frequency domain and the properties of the brain effective network i.e., causal flow, global efficiency and characteristic path length between such conditions. Also, some changes were more significant over the frontal brain lobes for the alpha frequency band. These findings might be used to detect drivers’ fatigue levels, and as reference work for future studies
Effects of Abnormal Savda Munzip on the Proliferation Activity and Migration Ability of Fibroblasts Derived from Hypertrophic Scar In Vitro
Background. To explore the effect of ASMq on proliferation and migration ability of the fibroblast derived from HS of donor (HSFbs) in vitro. Methods. The HSFbs were cultured from tissue specimens and passaged to the 3~4 generation, which were treated with the different concentrations of ASMq and 5-Fu from 1 to 11 days. The difference of HSFbs proliferation activity was analyzed by the CCK-8 method. The HSFbs migration ability in ASMq (0.4 mg/mL) was analyzed by the Cell Scratch method. Results. Transmission electron microscope result shows ASMq concentration significantly increases and fibroblast cell structure markedly change in the experimental group. The proliferation activity of the HSFbs was obviously weakened in ASMq groups than those of the group A (P<0.05) at seven days. The group C (0.4 mg/mL) is better suitable than other three ASMq treatment groups. Cell Migration Assay shows that the migration ability HSFbs was significantly reduced in ASMq (0.4 mg/mL) treatment group compared with those of blank control group at both 24 h and 48 h (P<0.05). Conclusions. These results suggest that ASMq effectively restrains the proliferation and migration ability of the HTSFbs in vitro, which can be one of the mechanisms for the prevention and treatment of HS
Can Drip Irrigation without Film Mulching Be Favorable for Potato Growth in Eastern China?
The main measures to improve potato cultivation in eastern China are film mulching and drip irrigation. However, the film can cause soil pollution and inhibit plant growth because of non-degradable polyethylene, which is the main component of the film. Whether drip irrigation without mulching can improve potato yield needs to be fully explored. Field experiments were conducted at the Special Potato Experimental Station, China Agricultural University, Rizhao City, Shandong Province, China, in 2019 and 2020 to investigate the effects of mulching and soil wetted percentage on soil water and temperature distribution, as well as potato growth. In 2019, three treatments with soil wetted percentage of 50% were set up: black plastic film mulching (BMP2), transparent plastic film mulching (TMP2), and no mulching (NMP2). In 2020, soil wetted percentage treatments were added to the existing mulching treatments: no mulching without irrigation (NMP0) and no mulching with soil wetted percentage of 25% (NMP1), 50% (NMP2), and 75% (NMP3); black plastic film mulching without irrigation (BMP0) and black plastic mulching with 50% soil wetted percentage (BMP2); and transparent plastic film mulching with no irrigation (TMP0) and transparent plastic film mulching with 50% soil wetted percentage (TMP2). The results indicated that mulching did not have a significant effect (p < 0.05) on soil temperature, potato growth, and yield. Irrigation reduced soil temperature by a range of 0.4 to 3.0 °C during the high air temperature season. Irrigation significantly increased potato plant height, stem thickness, and yield. The potato yield under the irrigation treatment could be 16.0–24.9% greater than that under the non-irrigation treatment. The highest irrigation water use efficiency (IWUE) was achieved at soil wetted percentage P1 and P2, which were beneficial for water saving. The NMP1 and NMP2 treatments had 83.4% and 81.0% significantly higher IWUE than NMP3 treatment. Considering environmental protection, resource conservation, and economic efficiency, drip irrigation without mulching under soil wetted percentage P2 was suitable for potato cultivation in eastern China
Electrochemical corrosion behavior of HVOF sprayed WC–12Co coating on H13 hot work mould steel
Stabilized Time Transfer via a 1000-km Optical Fiber Link Using High-Precision Delay Compensation System
Variations in optical fiber length and refractive index are induced by environmental perturbation, resulting in an additional dynamic propagation delay in fiber-based time synchronization systems, which deteriorate their transfer stability. This disadvantage can be significantly reduced by transmitting the time signal in both directions through fiber and constructing a feedback loop to compensate the propagation delay at the remote end of the link. This paper proposes an analog-digital hybrid proportional integral derivative (PID) control compensation system based on the time-frequency phase-locked loop (TF-PLL). The system is designed to keep the merits of wide servo bandwidth, servo accuracy, and a large dynamic delay compensation range up to 1 s, which is much greater than that reported in previous studies. For proving the validity of this proposed scheme, a self-developed optical fiber time synchronization equipment based on the delay compensation system is applied. The delay compensation system is used on a 1100-km long laboratory optical fiber, and the results show that the time synchronization stability in terms of time deviation (TDEV) is less than 5.92 ps/1 s and 2.56 ps/10,000 s. After successful laboratory evaluation, the proposed system is installed on a real 988.48-km line between the Xi’an Lintong branch of the National Time Service Center (NTSC) and Linfen City, Shanxi Province, realizing the time synchronization of 10 stations along the optical fiber link. The experimental results in the 988.48-km link illustrate that the measured time difference with a peak-to-peak value of 176 ps, the standard deviation of 19.3 ps, and a TDEV of less than 10.49 ps/1 s and 2.31 ps/40,000 s is achieved. The high-precision time delay compensation system proposed in this paper is simple, reliable, and accurate; has a wide range of compensation; and opens up a feasible scheme for providing synchronized time signals to multiple users over the long-distance field optical fiber networks