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Pneumonia is one of the diseases that seriously endangers human health, and it is also the leading cause of death of children under the age of five in China. The most commonly used imaging examination method for radiologists is mainly based on chest X-ray images. Still, imaging errors often result during imaging examinations due to objective factors such as visual fatigue and lack of experience. Therefore, this paper proposes a feature fusion model, FC-VGG, based on the fusion of texture features (local binary pattern LBP and directional gradient histogram HOG) and depth features. The model improves model performance by adding detailed information in texture features to the convolutional neural network while making the model more suitable for clinical use. We input the X-ray image with texture features into the modified VGG16 model, C-VGG, and then add the Add fusion method to C-VGG for feature fusion so that FC-VGG is obtained, so FC-VGG has texture features detailed information and abstract information of deep features. Through experiments, our model has achieved 92.19% accuracy in recognizing children’s pneumonia images, 93.44% average precision, 92.19% average recall, and 92.81% average F1 coefficient, and the model performance exceeds existing deep learning models and traditional feature recognition algorithms.

Background Coronavirus disease 2019 (COVID‐19) has reached a pandemic level. Cardiac injury is not uncommon among COVID‐19 patients. We sought to describe the electrocardiographic characteristics and to identify the prognostic significance of electrocardiography (ECG) findings of patients with COVID‐19. Hypothesis ECG abnormality was associated with higher risk of death. Methods Consecutive patients with laboratory‐confirmed COVID‐19 and definite in‐hospital outcome were retrospectively included. Demographic characteristics and clinical data were extracted from medical record. Initial ECGs at admission or during hospitalization were reviewed. A point‐based scoring system of abnormal ECG findings was formed, in which 1 point each was assigned for the presence of axis deviation, arrhythmias, atrioventricular block, conduction tissue disease, QTc interval prolongation, pathological Q wave, ST‐segment change, and T‐wave change. The association between abnormal ECG scores and in‐hospital mortality was assessed in multivariable Cox regression models. Results A total of 306 patients (mean 62.84 ± 14.69 years old, 48.0% male) were included. T‐wave change (31.7%), QTc interval prolongation (30.1%), and arrhythmias (16.3%) were three most common found ECG abnormalities. 30 (9.80%) patients died during hospitalization. Abnormal ECG scores were significantly higher among non‐survivors (median 2 points vs 1 point, p

BackgroundSince December 2019, a cluster of coronavirus disease 2019 (COVID-19) occurred in Wuhan, Hubei Province, China and spread rapidly from China to other countries. In-hospital mortality are high in severe cases and cardiac injury characterized by elevated cardiac troponin are common among them. The mechanism of cardiac injury and the relationship between cardiac injury and in-hospital mortality remained unclear. Studies focused on cardiac injury in COVID-19 patients are scarce.ObjectivesTo investigate the association between cardiac injury and in-hospital mortality of patients with confirmed or suspected COVID-19.MethodsDemographic, clinical, treatment, and laboratory data of consecutive confirmed or suspected COVID-19 patients admitted in Wuhan No.1 Hospital from 25thDecember, 2019 to 15thFebruary, 2020 were extracted from electronic medical records and were retrospectively reviewed and analyzed. Univariate and multivariate Cox regression analysis were used to explore the risk factors associated with in-hospital death.ResultsA total of 110 patients with confirmed (n=80) or suspected (n=30) COVID-19 were screened and 48 patients (female 31.3%, mean age 70.58±13.38 year old) among them with high-sensitivity cardiac troponin I (hs-cTnI) test within 48 hours after admission were included, of whom 17 (17/48, 35.4%) died in hospital while 31 (31/48, 64.6%) were discharged or transferred to other hospital. High-sensitivity cardiac troponin I was elevated in 13 (13/48, 27.1%) patents. Multivariate Cox regression analysis showed pulse oximetry of oxygen saturation (SpO2) on admission (HR 0.704, 95% CI 0.546-0.909, per 1% decrease, p=0.007), elevated hs-cTnI (HR 10.902, 95% 1.279-92.927, p=0.029) and elevated d-dimer (HR 1.103, 95%CI 1.034-1.176, per 1mg/L increase, p=0.003) on admission were independently associated with in-hospital mortality.ConclusionsCardiac injury defined by hs-cTnI elevation and elevated d-dimer on admission were risk factors for in-hospital death, while higher SpO2could be seen as a protective factor, which could help clinicians to identify patients with adverse outcome at the early stage of COVID-19.

Usually the settlement monitoring system was mainly applied in buildings, roads and so on in the city, which cannot meet the requirements of complex environments. While the train rail vibration monitoring, wind power platform settlement monitoring，etc are facing severe environmental interference. In order to ensure that rail, power tower platform and other field facilities to long-term and stable operation, there is a set of real-time monitoring system to monitor the settlement of the platform is particularly important. This paper proposes a new kind of high precision and micro displacement measurement technology based on laser and CCD devices, with the help of FPGA and MCU, we can complete the function of high-speed data acquisition and real-time monitoring easily. Compared with some traditional methods, this technology of measurement take great advantages in high-speed data acquisition, real-time performance, high-precision measurement and strong adaptability to complex environment, etc.

Background/purpose: The effect of aspirin on bone regeneration remains controversial. This study aimed to determine the effect of various concentrations of aspirin on cell viability, osteogenic differentiation, cell cycle, and apoptosis on ST2 cells to find an effective range of aspirin for bone regeneration induction. Materials and methods: Cell viability was measured with MTT assay after being stimulated with aspirin for 1 day, 2 days, 3 days, 5 days, and 7 days. Alkaline phosphatase (ALP) activity was measured after cells were treated for 1 day, 3 days, and 7 days. Expression of runt-related transcription factor 2 (Runx-2) was evaluated using Western-blot analysis at 3 days and 7 days. Flow cytometry was used for cell cycle and apoptosis measurement after cells were treated for 48 hours. Results: Lower concentrations of aspirin (1μΜ and 10μM) promoted cell growth and increased ALP levels and Runx-2 expression, while higher concentrations (100μΜ and 1000μΜ) inhibited cell growth (P

The aims of our study were to determine whether prenatal mercury levels are associated with the risk of preterm birth (PTB) and whether high maternal serum zinc (Zn) levels alleviate any negative effects of maternal mercury (Hg) exposure regarding PTB.Serum concentrations of Zn and Hg were measured in 3025 pregnant women from the Ma'anshan Birth Cohort. Before the collection of blood samples, they underwent examinations via the completion of questionnaires. The delivery records of the women were obtained from a series of medical records. We divided the study population into tertiles according to the participants' Hg levels: the low-Hg group (the first tertile,0.30 μg/L), the medium-Hg group (the second tertile, 0.30-0.43 μg/L) and the high-Hg group (the third tertile, ≥0.43 μg/L). The associations of Hg exposure with both the risk of PTB and gestational age (weeks) at birth were estimated using a binary logistic regression model and multivariable linear regression analysis, respectively. Afterwards, we conducted a repeated analyses test after the participants were stratified according to their Zn levels, using the 75th percentile division method.Overall, the medians and the interquartile ranges of Hg and Zn in the second trimester were 0.36 (0.27, 0.48) μg/L and 812.34 (731.26, 896.59) μg/L, respectively. Hg levels were associated with PTB [adjusted odds ratio (OR) and 95% confidence interval (95% CI): 1.91 (1.17, 3.12) for the third tertile vs. the first tertile of the serum Hg levels]. In the stratification analysis of the participants in the low-Zn group, the high-Hg group exhibited a significant odds ratio of PTB [adjusted OR (95% CI): 1.87 (1.08, 3.24)], compared to the low-Hg group. However, in the participants from the high-Zn group, the high-Hg group exhibited a non-significant OR of PTB [adjusted OR (95% CI): 2.32 (0.73, 7.42)]. In the multivariate linear regression analysis, gestational age (weeks) at delivery was significantly and inversely associated with the ln-transformed Hg concentrations [adjusted β (95% CI): -0.16 (-0.26, -0.06)]. Similarly, after the stratification analysis in the high-Zn group, there were no significant associations between PTB and the Hg levels [adjusted β (95% CI): -0.12 (-0.33, 0.09)].Prenatal Hg exposure adversely affected PTB, and high Zn levels alleviate this effect, which indicates that a more stringent control of Hg and a sufficient intake of Zn are necessary to help birth outcomes.

This paper studies the problem of joint allocation of subchannel, transmission power, and phase duration in the relay-enhanced bidirectional orthogonal frequency-division multiple access time division duplex systems. The challenges of this resource allocation problem arise from the complication of multiple-phase assignments within a subchannel since the relay station can provide an additional signal path from the base station to the user equipments (UEs). Existing research work does not fully consider all the influential factors to achieve feasible resource allocation for the relay-based networks. Since energy consumption is one of the principal issues, the energy minimization resource allocation (EMRA) schemes are proposed in this paper to design the allocation of subchannel, power, and phase duration for the UEs with the consideration of UE's quality-of-service (QoS) requirements. Both the four-phase and two-phase bidirectional relaying assignments and the network coding technique are adopted to obtain the suboptimal solutions for the proposed EMRA schemes. Different weights are designed for the UEs to achieve the minimization of weighted system energy for the relay-enhanced networks. Simulation results show that the proposed EMRA schemes can provide comparably better energy conservation and outage performance with QoS support.

To investigate the relationship between the changes of neural oscillations and the drug-seeking motivation,record the telemetric local field potentials (LFPs) of the prelimbic cortex (PrL) in the latency of drug-seeking behavior of conditioned place preference (CPP) rats induced by heroin.The recording electrode was stereotactically implanted intothe PrL cortex of rats. The animals were then randomly divided into operation-only control and heroin-induced CPP groups, respectively. A CPP video system in combination with awireless telemetry device was used for recording LFPs when the rats shuttled between black-white chamber for drug-seeking. The LFPs were analyzed by fast Fourier transform (FFT) and wavelet packet extraction.Compared with operation-only control group, the LFPs recorded in PrL area of heroin-induced CPP group of rat during black-white chamber shuttling showed that the percentage of θ rhythm were increased in right and left PrL, the percentage of γ3 rhythm was increased in left PrL, the phase-amplitude coupling of θ and γ3 was increased in left PrL. After MK-801 Maleate micro injection to PrL area,drug-seeking behavior of rat was markedly reduced and the percentage of θ oscillation was depressed,the phase-amplitude coupling of θ and γ3 was depressed in left PrL compared with operation-only control group.These results suggest that increase of θ oscillations of PrL area may be related to the drug-seeking motivation and behavior launching in heroin-induced CPP groups of rat. The changes of θ oscillations also have close relationship with glutamatergic neuron and the receptor of it on PrL area.

To investigate the changes of shock avoidance response in Y maze and the real-time local field potentials (LFPs) on hippocampal CA3 region in adolescent rats with high fat feeding.The juvenile rats of weaning 1 week were fed separately on basic feed (BF) and high fat diet (HFD) for 4 weeks until the puberty. Using the electric shock avoidance training method, the relevant parameters of reaching the learning standard of two groups of rats were recorded, and the LFPs of CA3 region in hippocampus were explored simultaneously by wireless telemetry.Compared with the BF group, the body weight of HFD rats were increased significantly(From juvenile to adolescent with HFD intake, the adolescent rat gained an increase significantly in weight,but the ability of shock avoidance and the function of hippocampus-dependent spatial cognition in Y maze had not be expected decline.

Consider the effect of spray droplets and foams on the radar altimeter, an improved algorithm of retrieving oceanic surface wind speed is proposed in this study. Firstly, a four-layer medium model is established in order to simulate accurately the air–sea interface. Secondly, the microwave reflectivity of the established model is computed at 13.5 GHz. The computed results show that the effect of spray droplets and foams plays an important role in the reflectivity of the air–sea surface and causes it to decline from 0.6 to 0.23. Thirdly, the computed results are applied to retrieve the sea surface wind speed and an improved algorithm of retrieving wind speed is proposed. At low wind speeds, the improved algorithm is in good agreements with those reported results, and at high wind speeds is also in good agreements with some empirical algorithms presented by Brown, Young and so on. Finally, the improved algorithm can improve the sea surface wind speed retrieval more effectively and also is closer to the actual situation of the sea surface than those algorithms based on the three-layer medium model.

At high sea states strong winds make the sea surface broken, and become a multilayer-rough sea surface made of a large number of foams and droplets. Similarly, if the sea surface covered by oil and other dirts will also belong to the mutilayer rough sea surfaces of various medium properties. In this paper, applying the Kirchhoff Approximation (KA) and the electromagnetic theory of stratified media, electromagnetic scattering characteristics from a multilayer rough medium surface are calculated. Firstly, a detailed analysis of electromagnetic reflection from multilayer parallel interfaces under different incident angles is carried out. Secondly, combining the preceding two results and courses, electromagnetic scattering from the multilayer random rough surfaces is studied. The computed results are in good agreement with those by using the method of moments (MOM) and reported by some experts. Finally, the random rough sea surface covered by spilling oil or droplets and foams is calculated in detail. Compared with MOM, the new approximate analysis method in the paper can avoid a large matrix inversion, and thus greatly reduce the computation time and improve the computational efficiency.

Considering about the effect of whitecaps and foams on pulse-limited Radar Altimeters, an improved algorithm of retrieving sea surface wind speed is proposed in this paper. Firstly, a four-layer dielectric model is established in order to simulate an air-sea interface. Secondly, the microwave reflectivity of a sea surface covered by spray droplets and foams at 13.5 GHz is computed based on the established model. These computed results show that the effect of spray droplets and foams in high sea state conditions shall not be negligible on retrieving sea surface wind speed. Finally, compared with the analytical algorithms proposed by Zhao and some calculated results based on a three-layer dielectric model, an improved algorithm of retrieving sea surface wind speed is presented. At a high wind speed, the improved algorithm is in a better accord with some empirical algorithms such as Brown, Young ones and et al., and also in a good agreement with ZT and other algorithms at low wind speed. This new improved algorithm will be suitable not only for low wind speed retrieval, but also for high wind speed retrieval. Better accuracy and effectiveness of wind speed retrieval can also be obtained.

To study the correlation between EEG characteristics of medial prefrontal cortex (mPFC) and drug-seeking behavior of rats with morphine dependent place preference under shuttling condition.Forty rats were randomly divided into four groups (n = 10): morphine PL group, NS PL group, morphine IL group and NS IL group. After embeding the electrode in prelimbic (PL) or infralimbic (IL) cortex of each group by brain stereotaxic operation, the model of morphine dependent conditioned place preference (CPP) in rats was established. The differences of EEG wave percentage in mPFC were telemetered and analyzed when rats shuttled before and after the model.After the model, the withdrawal symptoms were evident in morphine PL and IL group, and the activity time and distance in white box were increased obviously. Compared with control group, after the model, the EEG in morphine PL group showed that: when the rats shuttled to white box, 8 wave decreased obviously, P wave increased obviously. When the rats shuttled to black box, brain waves showed opposite changes. The EEG in morphine IL group showed that: when the rats shuttled to white box, a wave increased obviously, P and a wave decreased obviously. When the rats shuttled to black box, the brain wave had no significant differences compared with control group.The EEG changes are different in PL and IL cortex of morphine CPP rats under shuttling condition, and the EEG changes are also different when rats shuttling to white or black box. There is possibly different mechanism, when different drug-seeking environmental cues caused EEG changes in different regions of mPFC.

To determine the effect of aspirin on cell proliferation, alkaline phosphatase (ALP) activity, cell cycle and apoptosis in murine bone marrow stromal cells, so as to explore an appropriate dose range to improve bone regeneration in periodontal treatment.ST2 cells were stimulated with aspirin (concentrations of 1, 10, 100 and 1 000 μmol/L) for 1, 2, 3, 5 and 7 d. Cell proliferation was measured by methyl thiazolyl tetrazolium (MTT) assay. After ST2 cells were treated for 1, 3 and 7 d, ALP activity was measured by ALP kit, cell cycle and apoptosis were measured by flow cytometry (FCM) after treated for 48 h.MTT assays showed that various doses of aspirin have different effects on the cell growth. Briefly, lower concentrations (1, 10 μmol/L) of aspirin promoted the cell growth, the A value of 0, 1 and 10 μmol/L aspirin 7-day-treated cells were 0.313±0.012, 0.413±0.010 and 0.387±0.017 respectively (P0.01 vs control), and so did the ALP level ([4.3±0.9], [6.0±0.3] and [7.7±0.4] μmol·min(-1)·g(-1), P0.05 vs control), while higher concentrations, especially 1000 μmol/L of aspirin might inhibit the cell growth with time going, A value and ALP level were 0.267±0.016, (4.3±1.3) μmol·min(-1)·g(-1) respectively (P0.05 vs control). Cell cycle analysis revealed no changes in comparison to control cells after treatment with 1 or 10 μmol/L aspirin, but it was observed that cell mitosis from S phase to G2/M phase proceeded at higher concentrations of 100 μmol/L aspirin, and the cell cycle in phase G0/G1 arrested at 1000 μmol/L. Parallel apoptosis/necrosis studies showed that the percentage of cells in apoptosis decreased dramatically at all doses of aspirin, the apoptosis rates of ST2 cells responded to 0, 1, 10, 100 and 1000 μmol/L aspirin were (11.50±0.90)%, (5.30±0.10)%, (5.50±0.10)%, (4.90±0.90)% and (7.95±0.25)% respectively (P0.05 vs control).This study demonstrated that lower dosage of aspirin can promote ST2 cells growth, osteogenic activity and inhibit its apoptosis. Aspirin maybe used for the bone reconstruction with a proper concentration.

The purpose of the present study is to explore the relationship of spatial learning ability and specific electrical activities of neural oscillations in the rat. The fast and general avoidance response groups were selected on the basis of the animals' responses to the electric shock in Y type maze, and their local field potentials (LFPs) of hippocampal CA3 area were recorded by wireless telemetry before and after shock avoidance training, respectively. The components of neural oscillations related to spatial identifying and learning ability were analyzed. The results showed that, compared with the general avoidance response group, the fast avoidance response group did not show any differences of LFPs in hippocampal CA3 area before electric shock avoidance trial, but showed significantly increased percentages of 0-10 Hz and 30-40 Hz rhythm in right hippocampal CA3 area after the shock avoidance training (P0.01 or P0.05). Fast Fourier transform showed that percentage increase of 0-10 Hz band occurred mainly in θ (3-7 Hz) frequency, and 30-40 Hz frequency change was equivalent to the γ1 band. Furthermore, compared with those before training, only the percentages of β, β2 (20-30 Hz) and γ1 rhythm increased (P0.01 or P0.05) in fast avoidance response rats after training, while the θ rhythm percentage remained unchanged. In contrast, θ rhythm percentage and the large amplitude (intensity: +2.5 - -2.5 db) θ waves in right CA3 area of general avoidance response rats were significantly reduced after training (P0.01). These results suggest that the increased percentages of β2 and γ1 rhythm and high-level (unchanged) percentage of θ rhythm in the right hippocampus CA3 area might be related to strong spatial cognition ability of fast avoidance response rats.