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Entangled microwave signal is a new quantum information resource generated in recent years. We present that entangled microwave signals can be used as the medium to realize quantum information transmission. Focusing on the divergent problem of propagation, a partial detection model based on beam splitter is established to investigate the detection efficiency and influence factors of entangled microwave signals. We analyze the relation between the entanglement degree of partial detection and detection ratio and discuss the reason that causes the reduction of entanglement degree. We give ameliorative designs of microwave signal generator and transmitter to increase the operating distance and pave the way for the application of entangled microwave signals. Keywords: Entangled microwave signals, Partial detection, Beam splitter, Entanglement degree

Pine wilt disease (PWD) is a global devastating threat to forest ecosystems. Therefore, a feasible and effective approach to precisely monitor PWD infection is indispensable, especially at the early stages. However, a precise definition of “early stage” and a rapid and high-efficiency method to detect PWD infection have not been well established. In this study, we systematically divided the PWD infection into green, early, middle, and late stages based on the needle color, the resin secretion, and whether the pine wood nematode (PWN) was carried. Simultaneously, an unmanned aerial vehicle (UAV) equipped with multispectral cameras was used to obtain images. Two target detection algorithms (Faster R-CNN and YOLOv4) and two traditional machine learning algorithms based on feature extraction (random forest and support vector machine) were employed to realize the recognition of infected pine trees. Moreover, we took into consideration of the influence of green broad-leaved trees on the identification of pine trees at the early stage of PWD infection. We obtained the following results: (1) the accuracy of Faster R-CNN (60.98–66.7%) was higher than that of YOLOv4 (57.07–63.55%), but YOLOv4 outperformed in terms of model size, processing speed, training time, and testing time; (2) although the traditional machine learning models had higher accuracy (73.28–79.64%), they were not able to directly identify the object from the images; (3) the accuracy of early detection of PWD infection showed an increase of 3.72–4.29%, from 42.36–44.59% to 46.08–48.88%, when broad-leaved trees were considered. In this study, the combination of UAV-based multispectral images and target detection algorithms allowed us to monitor the occurrence of PWD and obtain the distribution of infected trees at an early stage, which can provide technical support for the prevention and control of PWD.

Animal and imaging study evidence favors early reperfusion for acute myocardial infarction. However, in clinical trials, the effect of symptom-onset-to-balloon (S2B) time on clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI) has been inconsistent. Moreover, there are few data regarding the ischemic time in China. A total of 3,877 consecutive patients with STEMI with available S2B time undergoing pPCI from January 2013 to September 2014 at 108 hospitals that participated in the China Acute Myocardial Infarction registry were included and stratified into 3 S2B groups:6 hours, 6 to 12 hours,12 hours S2B time was tested in multivariate logistic regression analyses as an independent risk factor of mortality (primary outcome), major adverse cardiovascular and cerebrovascular events (MACCE), and impaired myocardial perfusion (secondary outcomes). The median S2B time was 5.5 (3.75 to 8.50) hours. Longer S2B time was associated with higher in-hospital mortality (6 hours: 2.7%; 6 to 12 hours: 3.4%;12 hours: 4.9%; p = 0.047) and ST-segment resolution50% (6 hours: 16.7%; 6 to 12 hours: 19.2%;12 hours: 24.3%; p = 0.002) but not MACCE. In multivariate-adjusted analysis, S2B12 hours remained associated with ST-segment resolution50% (odds ratio 1.53, 95% confidence interval 1.16 to 2.01, p = 0.002) but not with in-hospital mortality (odds ratio 1.673, 95% confidence interval 0.95 to 2.94, p = 0.073). In conclusion, median S2B time in patients with STEMI undergoing pPCI was longer than that in registry studies from other countries. Longer S2B time was associated with impaired myocardial perfusion but not with in-hospital mortality or MACCE.

Background: Permanent polymer drug eluting stents (PP-DES) may induce inflammation of the vessel wall due to the existence of the polymer, which may delay intimal healing. Polymer-free DES (PF-DES) that eliminate the polymeric carrier may potentially lead to safer DES. However, the safety and efficacy of PF-DES remains controversial. Methods: Randomized controlled trials comparing PF-DES with PP-DES were searched in online database including MEDLINE, Excerpta Medica Database (EMBASE) and Cochrane Library. Studies reporting late lumen loss (LLL), all-cause death, myocardial infarction (MI), target lesion revascularization (TLR) and late stent thrombosis (LST) were enrolled and quantitatively analyzed. Results: Ten studies enrolling 6575 patients were included in this meta-analysis. The PF-DES showed a benefit in reducing all-cause death (ORÂ =Â 0.77, 95% CI: 0.61 to 0.98, PÂ =Â 0.03) and long-term LLL (weighted mean difference (WMD) â0.16Â mm, 95% CI: â0.22 to â0.11Â mm, PÂ

We discuss the relationship between the photon frequency used to produce a continuous variable entangled microwave signal and the signal frequency used for its measurement. We analyze the bandwidth of the continuous variable entangled microwave signal and characterize quantum fluctuations using a quantum sideband representation. The quantum fluctuations of entangled microwave signal follow a true random distribution that is similar to noise. And entangled information is reflected by quantum fluctuations. We conclude that the frequency of generated photons corresponds to the center frequency obtained after performing a Fourier transform on the measured signal, whereas the bandwidth of entangled microwave signal is infinite. Due to the high precision of the measurement from its ultra-wideband behavior, as well as the security afforded by the true randomness and non-localized quantum correlation, these entangled microwaves show significant advantages and potential application value in various fields. Keywords: Entangled microwave signal, Photon frequency, Signal frequency, Signal bandwidth