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A mathematical model of variable inclination continuous transverse stub (VICTS) antenna for low sidelobe design is proposed in this paper. VICTS antenna is an antenna with continuous transverse stubs on the parallel-plate waveguide and additional branches attached to the transverse stubs to generate radiation. The antenna using this technique has high aperture efficiency and keeps a significant solution for high-gain antenna. However, the sidelobe level (SLL) of this antenna is relatively high and increases continuously as the pitch angle decreases. This paper presents a fast calculation model for the SLL of VICTS antennas using leaky-wave theory and antenna array theory. The full-wave simulation results and model calculation results are in good agreement, so this model can be used for SLL suppression of VICTS antennas in different frequency bands. By controlling the aperture field distribution to be tapered, the SLL is suppressed to − 23.7 dB using this mathematical model.
With the characteristics of full autonomy and no accumulated errors, polarisation navigation shows tremendous prospects in underwater scenarios. In this paper, inspired by the polarisation vision of aquatic organisms, a novel point-source polarisation sensor with high spectral adaptability (400 nm–760 nm) is designed for underwater orientation. To enhance the environmental applicability of the underwater polarisation sensor, a novel sensor model based on the underwater light intensity attenuation coefficient and optical coupling coefficient is established. In addition, concerned with the influence of light intensity uncertainty on sensor performance underwater, an antagonistic polarisation algorithm is adopted for the first time, to improve the accuracy of angle of polarisation and degree of polarisation in the low signal-to-noise ratio environment underwater. Finally, indoor and outdoor experiments are carried out to evaluate the performance of the designed polarisation sensor. The results show that the designed point-source polarisation sensor can acquire polarised light and be used for heading determination underwater.
This study explored the clinical effect of employing breast milk oral care for infants who underwent surgical correction of ventricular septal defect.
A prospective randomised controlled study was conducted in a provincial hospital between January, 2020 and July, 2020 in China. Patients were randomly divided into an intervention group (breast milk oral care, n = 28) and a control group (physiological saline oral care, n = 28). The intervention group was given oral nursing using breast milk for infants in the early post-operative period, and the control group was given oral nursing using physiological saline. Related clinical data were recorded and analysed.
There were no significant differences in age, gender, weight, operation time, cardiopulmonary bypass time, or aortic cross-clamping time between the two groups. Compared with the physiological saline oral care group, the mechanical ventilation duration, the length of ICU stay in the breast milk oral care group were significantly shorter. The time of start feeding and total enteral nutrition were significantly earlier in the intervention group than those in the control group. The incidence of post-operative pneumonia in the breast milk oral care group was 3.6%, which was significantly lower than that of the physiological saline oral care group.
The use of breast milk for oral care in infants who underwent surgical correction of VSD can reduce the incidence of post-operative pneumonia and promote the recovery of gastrointestinal function.
Pulmonary arterial hypertension symptoms in systemic lupus erythematosus patients are non-specific and early diagnosis and intervention are challenging. It remains essential to explore risk factors for pulmonary arterial hypertension in systemic lupus erythematosus patients to identify high risk patients and allow intensive monitoring.
From January 2010 to December 2018, 84 patients with systemic lupus erythematosus and pulmonary arterial hypertension and 160 patients with systemic lupus erythematosus but without pulmonary arterial hypertension were enrolled. Clinical manifestations and laboratory test results were compared between the two groups to identify predictors of pulmonary arterial hypertension. Candidate pulmonary arterial hypertension risk factors were further compared among systemic lupus erythematosus-pulmonary arterial hypertension patients with different characteristics.
Among collected patient characteristics, Raynaud’s phenomenon (OR 2.32, 95% CI: 1.17–4.61), digital vasculitis (OR 4.12, 95% CI: 1.48–11.49), pericardial effusion, pulmonary interstitial lesions, positive anti-u1 ribonucleoprotein antibodies, and positive anticardiolipin antibodies immunoglobulin G were associated with significantly higher risk of pulmonary arterial hypertension in systemic lupus erythematosus patients. Among these candidate risk factors, positive anti-u1 ribonucleoprotein antibody was independently associated with severe pulmonary arterial hypertension and more active disease. Digital vasculitis was independently associated with systemic lupus erythematosus alleviation, while pericardial effusion was associated with systemic lupus erythematosus deterioration. Pericardial effusion was associated with longer pulmonary arterial hypertension duration.
The significant association between studied clinical and laboratory indicators and risk of pulmonary arterial hypertension, pulmonary arterial hypertension and systemic lupus erythematosus characteristics suggested that these factors can be used to identify patients at higher risk of pulmonary arterial hypertension and adverse outcomes. Close monitoring may be indicated in patients with these risk factors, especially with more than one risk factor.
The TanDEM-X DEM is a valuable data source for estimating glacier mass balance. However, the accuracy of TanDEM-X elevation over glaciers can be affected by microwave penetration and phase decorrelation. To investigate the bias of TanDEM-X DEMs of glaciers on the Tibetan Plateau, these DEMs were subtracted from SPOT-6 DEMs obtained around the same time at two study sites. The average bias over the studied glacier areas in West Kunlun (175.0 km2) was 2.106 ± 0.012 m in April 2014, and it was 1.523 ± 0.011 m in Geladandong (228.8 km2) in October 2013. By combining backscatter coefficients and interferometric coherence maps, we found surface decorrelation and baseline decorrelation can cause obvious bias in addition to microwave penetration. If the optical/laser data and winter TanDEM-X data were used as new and historic elevation sources for mass-balance measurements over an arbitrary observation period of 10 years, the glacier mass loss rates in West Kunlun and Geladandong would be potentially underestimated by 0.218 ± 0.016 and 0.158 ± 0.011 m w.e. a−1, respectively. The impact is therefore significant, and users should carefully treat the bias of TanDEM-X DEMs when retrieving a geodetic glacier mass balance.
The research was to introduce the experience of doubly committed subarterial ventricular septal defect (DCVSD) repaired through tricuspid approach.
From January, 2015 to September, 2019, 86 consecutive DCVSD paediatrics underwent repair via right subaxillary vertical incision (RAVI) through tricuspid approach. Perioperative and follow-up data were collected.
The age and weight at operation were 28.1 ± 18.5 (range: 7–101) months and 12.2 ± 4.2 (6–26.5) kg. There were two patients combined with discrete subaortic membrane, two patients with patent ductus arteriosus, one patient with atrial septal defect, and two patients with abnormal muscle bundle in right ventricular outflow tract. The mean size of ventricular septal defect was 7.0 ± 2.4 (3–13) mm. The defect was repaired with a piece of Dacron patch in 68 patients or directly with 1–2 pledgetted polypropylene sutures in 18 patients. The cardiopulmonary bypass time and aortic cross-clamp time were 46.2 ± 13.3 (23–101) minutes and 29.2 ± 11.5 (12–84) minutes. After 3.1 ± 2.4 (0–14) hours’ ventilator assist and 23.2 ± 32.1 (0–264) hours’ ICU stay, all patients were discharged safely. At the latest follow-up (27.9 ± 14.6 months), echocardiography showed trivial residual shunt in two patients. There was no malignant arrhythmia occurred and there was no chest deformity or asymmetrical development of the breast was found.
DCVSD repaired via right subaxillary vertical incision through tricuspid approach was safe and feasible, providing a feasible alternative to median sternotomy, and it can be performed with favourable cosmetic results.
Preferential flow that leads to non-uniform displacement, especially in heterogeneous porous media, is usually unwelcome in most practical processes. We propose a self-adaptive preferential flow control mechanism by using dispersed polymers, which is supported strongly by experimental and numerical evidence. Our experiments are performed on a microchip with heterogeneous porous structures where oil is displaced by dispersed polymer microsphere particles. Even though the size of the particles is much smaller than the pore-throat size, the diversion effect by the dispersed microspheres is still proved. Therefore, the plugging effect is not the major mechanism for preferential flow control by dispersed polymers. The mechanisms are further investigated by pore-scale modelling, which indicates that the dispersed polymers exhibit an adaption ability to pressure and resistance in the porous flow field. In such an intelligent way, the displacing fluid with dispersed polymers smartly controls the preferential flow by inducing pressure fluctuations, and demonstrates better performance in both efficiency and economic aspects than the traditional method by simply increasing the viscosity. These insights can be applied to improve techniques in the field, such as enhanced oil recovery and soil wetting.
Mesanophrys sp. is a newly identified parasitic ciliate infecting farmed swimming crab. To demonstrate the correlation between parasite development and environmental conditions, this study aimed to investigate the effect of temperature, salinity, pH and frequency of passage of parasite on survival, growth and body size of Mesanophrys sp. in vitro. The results revealed that survival, population density and growth rate of the parasite were highest at 12°C and decreased with increasing temperature from 16 to 26°C. In addition, the survival, population density and growth rate of Mesanophrys sp. were high at 20‰. When salinity was adjusted to levels lower (0–10‰) and higher (40–60‰) than 20‰, the parasite's survival and growth rate gradually declined. The optimal pH for parasite survival was 8.0, whereas its survival was inhibited at <4.5 or >9.5. Our result also showed that parasite body proportions (length:width) were significantly smaller at the highest temperature compared to the lower temperature, whereas different salinities had no significant effect. Furthermore, we introduced dynamic parasite culture systems in vitro where Mesanophrys sp. was cultured in medium-containing culture plates through continually reducing and halving the old medium into fresh. Application of this optimized dilution timing technique with fresh medium and sub-cultured enabled a continuous culture of parasites. Under this optimized condition, the highest population density and exponential growth rate of the parasite were achieved than that of a control group. This study will help to understand the ciliated parasite infection dynamics and provides new possibilities for in vitro parasite-associated studies.
The recent scientific progress has shown the promising effect of the vaccine in immunotherapy of cancer, which relies on the antigen processing/presentation capability of dendritic cells (DCs). As a result, cancer vaccines targeting DC, which also named as DC vaccine, was a hot-spot in vaccine development. Herein, a nanostructured lipid carrier (NLC) was employed to load chlorin e6 (Ce6) to serve as a potential in situ DC vaccine (NLC/Ce6) for effective immunotherapy of gastric cancer. Taking advantage of the photodynamic effect of Ce6 to generate reactive oxygen species (ROS) under laser irradiation, the NLC/Ce6 was able to trigger cell death and expose tumor-associated antigen (TAA). Moreover, mimicking the natural inflammatory response, the ROS can also recruit the DC for the effective processing/presentation of the in situ exposed TAA. As expected, we observed strong capability DC vaccination efficacy of this platform to effectively inhibit the growth of both primary and distant gastric tumors.
Mainland China has not adopted the UN Commission on International Trade Law (UNCITRAL) Model Law, nor has it permitted ad hoc arbitration. Yet, arbitration in China is developing rapidly. According to the data released by the Ministry of Justice on March 2019, at the end of 2018 there were 255 arbitration commissions established with more than 60,000 staff members in mainland China.1 The caseload of 2018 is 540,000, which was a 127 percent increase compared to that in 2017.2 The stakes involved in 2018 are around 700 billion RMB.3 Since the promulgation of the Chinese Arbitration Law (CAL) in 1994, domestic arbitral commissions have handled over 2.6 million cases involving more than seventy countries/regions.4 Additionally, judicial review of arbitration in China has undergone changes over the last decades. The Chinese Arbitration Law has gone through heated discussions of amendment, and the Supreme People’s Court’s (SPC) judicial interpretations have contributed significantly to the development of Chinese arbitration. With the acceleration of open-up policy and the implementation of the Belt and Road Initiative (BRI), China endeavors to elevate its international image by providing fair, transparent, and efficient judicial services for international dispute resolution. Judicial attitude toward arbitration becomes more open minded than ever before. In earlier days, foreign investors had little information on the prospects of enforceability of arbitral awards in mainland China. The uncertainty inevitably affected their decisions on whether to choose arbitration as a dispute resolution mechanism when doing business with Chinese counterparts.
The potential relationship between service demands and remanufacturing services (RMS) is essential to make the decision of a RMS plan accurately and improve the efficiency and benefit. In the traditional association rule mining methods, a large number of candidate sets affect the mining efficiency, and the results are not easy for customers to understand. Therefore, a mining method based on binary particle swarm optimization ant colony algorithm to discover service demands and remanufacture services association rules is proposed. This method preprocesses the RMS records, converts them into a binary matrix, and uses the improved ant colony algorithm to mine the maximum frequent itemset. Because the particle swarm algorithm determines the initial pheromone concentration of the ant colony, it avoids the blindness of the ant colony, effectively enhances the searchability of the algorithm, and makes association rule mining faster and more accurate. Finally, a set of historical RMS record data of straightening machine is used to test the validity and feasibility of this method by extracting valid association rules to guide the design of RMS scheme for straightening machine parts.
In order to elucidate the physical connection between the propulsive performance and the unsteadiness of jet flow, the transient development of the impulse and thrust of laminar starting jets with finite fluid discharged is investigated numerically for cases with different velocity programmes and jet stroke ratios. The simulation quantitatively demonstrates that the impulse and thrust generated are highly sensitive to the jet kinematics and its near-wake dynamics. The momentum flux contribution to the jet impulse is found to be significant and is associated closely with the jet kinematics. On the other hand, although the over pressure effect at the jet initiation stage has been identified previously as the main reason for the enhanced propulsive performance of the starting jet, the current results indicate that its contribution is in fact weakened by the negative local pressure, induced by the formation of the leading vortex ring as well as jet development during the deceleration stage. Contrary to the effects of the leading vortex ring, the stopping vortex formed near the nozzle exit plane during the jet deceleration stage is found to contribute positively to the pressure impulse production, albeit it is relatively small. By augmenting the over pressure effect and mitigating the negative-pressure effect, the cases with the fast acceleration and slow deceleration velocity programme is capable of producing the maximum pressure impulse, leading to additional impulse production over what would be expected from the jet momentum flux alone.
The Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a public health emergency of international concern. The current study aims to explore whether the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are associated with the development of death in patients with COVID-19. A total of 131 patients diagnosed with COVID-19 from 13 February 2020 to 14 March 2020 in a hospital in Wuhan designated for treating COVID-19 were enrolled in the current study. These 131 patients had a median age of 64 years old (interquartile range: 56–71 years old). Furthermore, among these patients, 111 (91.8%) patients were discharged and 12 (9.2%) patients died in the hospital. The pooled analysis revealed that the NLR at admission was significantly elevated for non-survivors, when compared to survivors (P < 0.001). The NLR of 3.338 was associated with all-cause mortality, with a sensitivity of 100.0% and a specificity of 84.0% (area under the curve (AUC): 0.963, 95% confidence interval (CI) 0.911–1.000; P < 0.001). In view of the small number of deaths (n = 12) in the current study, NLR of 2.306 might have potential value for helping clinicians to identify patients with severe COVID-19, with a sensitivity of 100.0% and a specificity of 56.7% (AUC: 0.729, 95% CI 0.563–0.892; P = 0.063). The NLR was significantly associated with the development of death in patients with COVID-19. Hence, NLR is a useful biomarker to predict the all-cause mortality of COVID-19.
Fat-soluble vitamins during pregnancy are important for fetal growth and development. The present study aimed at exploring the association between vitamin A, E and D status during pregnancy and birth weight. A total of 19 640 women with singleton deliveries from a retrospective study were included. Data were collected by the hospital electronic information system. Maternal serum vitamin A, E and D concentrations were measured during pregnancy. Logistic regression was performed to estimate the association between the vitamin status and low birth weight (LBW) or macrosomia. Women with excessive vitamin E were more likely to have macrosomia (OR 1·30, 95 % CI 1·07, 1·59) compared with adequate concentration. When focusing on Z scores, there was a positive association between vitamin E and macrosomia in the first (OR 1·07, 95 % CI 1·00, 1·14), second (OR 1·27, 95 % CI 1·11, 1·46) and third (OR 1·28, 95 % CI 1·06, 1·54) trimesters; vitamin A was positively associated with LBW in the first (OR 1·14, 95 % CI 1·01, 1·29), second (OR 1·31, 95 % CI 1·05, 1·63) and third (OR 2·00, 95 % CI 1·45, 2·74) trimesters and negatively associated with macrosomia in the second (OR 0·79, 95 % CI 0·70, 0·89) and third (OR 0·77, 95 % CI 0·62, 0·95) trimesters. The study identified that high concentrations of vitamin E are associated with macrosomia. Maintaining a moderate concentration of vitamin A during pregnancy might be beneficial to achieve optimal birth weight. Further studies to explore the mechanism of above associations are warranted.
Increased intake of vegetables and fruits has been associated with reduced risk of tuberculosis infection. Vegetables and fruits exert immunoregulatory effects; however, it is not clear whether vegetables and fruits have an adjuvant treatment effect on tuberculosis. Between 2009 and 2013, a hospital-based cohort study was conducted in Linyi, Shandong Province, China. Treatment outcome was ascertained by sputum smear and chest computerised tomography, and dietary intake was assessed by a semi-quantitative FFQ. The dietary questionnaire was conducted at the end of month 2 of treatment initiation. Participants recalled their dietary intake of the previous 2 months. A total of 2309 patients were enrolled in this study. After 6 months of treatment, 2099 patients were successfully treated and 210 were uncured. In multivariate models, higher intake of total vegetables and fruits (OR 0·70; 95 % CI 0·49, 0·99), total vegetables (OR 0·68; 95 % CI 0·48, 0·97), dark-coloured vegetables (OR 0·61; 95 % CI 0·43, 0·86) and light-coloured vegetables (OR 0·67; 95 % CI 0·48, 0·95) were associated with reduced failure rate of tuberculosis treatment. No association was found between total fruit intake and reduced failure rate of tuberculosis treatment (OR 0·98; 95 % CI 0·70, 1·37). High intake of total vegetables and fruits, especially vegetables, is associated with lower risk of failure of tuberculosis treatment in pulmonary tuberculosis patients. The results provide important information for dietary guidelines during tuberculosis treatment.
The present study investigated the influence of berberine (BBR) supplementation in normal and high-lipid (HL) diets on lipid metabolism and accumulation in black sea bream (Acanthopagrus schlegelii). BBR was supplemented at 50 mg/kg to control (Con, 11·1 % crude lipid) and high-lipid (HL, 20·2 % crude lipid) diets and named as ConB and HLB, respectively. After the 8-week feeding trial, fish body length and specific growth rate were significantly reduced by HL diets (P < 0·05). Muscle and whole-body crude lipid contents were significantly influenced by both BBR supplementation and dietary lipid level. Fish fed the HLB diet had significantly lower serum TAG, LDL-cholesterol contents and alanine aminotransferase activity compared with the HL group. The HL group presented vast lipid accumulation in the liver, and hypertrophied hepatocytes along with large lipid droplets, and translocation of nuclear to the cell periphery. These abnormalities in black sea bream were alleviated in the HLB group. BBR supplementation in the HL diet significantly down-regulated the hepatic expression levels of acetyl-CoA carboxylase α, sterol regulatory element-binding protein-1, 6-phosphogluconate dehydrogenase, glucose 6-phosphate dehydrogenase and pparγ, whereas the lipoprotein lipase, hormone-sensitive lipase and carnitine palmitoyltransferase 1a expression levels were significantly up-regulated. However, the expression levels of these genes showed opposite trends in muscle (except for pparγ). In conclusion, dietary BBR supplementation in the HL diet reduced hepatic lipid accumulation by down-regulating lipogenesis gene expression and up-regulating lipolysis gene expression, and it increased muscle lipid contents with opposite trends of the mechanism observed in the liver.
Three-dimensional flow fields of a rectangular synthetic jet with aspect ratio of 3 and its interaction with a laminar cross-flow are measured using time-resolved tomographic particle image velocimetry. The synthetic-jet to free-stream velocity ratio is fixed at 1, and two orifice orientations, normal to (spanwise configuration) and aligned with (streamwise configuration) the cross-flow direction, respectively, are investigated. The flow scenarios are composed of a tilted vortex ring, a secondary trailing vortex and a tertiary near-wall vortex. Compared to previous results for circular cases, the legs of the trailing structures are found to be jointed in the spanwise direction by two shear-layer vortices at different wall-normal heights. In addition, the near-wall vortex is a crescent-shaped spanwise vortex. For the first time, as the peculiar process of non-circular vortex rings in quiescent condition, axis switching is validated to exist in the cross-flow. Associated with axis switching, the spanwise case exhibits interaction between the leeward vortex of the vortex ring and the downstream shear-layer vortex, which causes slower penetration and recovery of vortex ring tilting, but faster jet transition. Furthermore, the trailing structures and vortex ring are weakened, leading to lower peaks of the velocity deficit and overshoot in the jet region than those for the streamwise case. On the other hand, the spanwise case can induce a stronger near-wall vortex, which transfers more momentum and initial disturbance into the boundary layer. Consequently, the spanwise case yields larger velocity gradient and velocity fluctuation peak inside the boundary layer with a lower shape factor, suggesting greater efficiency of promoting boundary-layer transition.
A 6-week growth trial was conducted to evaluate the influences of dietary valine (Val) levels on growth, protein utilisation, immunity, antioxidant status and gut micromorphology of juvenile hybrid groupers. Seven isoenergetic, isoproteic and isolipidic diets were formulated to contain graded Val levels (1·21, 1·32, 1·45, 1·58, 1·69, 1·82 and 1·94 %, DM basis). Each experimental diet was hand-fed to triplicate groups of twelve hybrid grouper juveniles. Results showed that weight gain percentage (WG%), protein productive value, protein efficiency ratio, and feed efficiency were increased as dietary Val level increased, reaching a peak value at 1·58 % dietary Val. The quadratic regression analysis of WG% against dietary Val levels indicated that the optimum dietary Val requirement for hybrid groupers was estimated to be 1·56 %. Gut micromorphology and expression of growth hormone in pituitary, insulin-like growth factor 1, target of rapamycin and S6 kinase 1 in liver were significantly affected by dietary Val levels. In serum, fish fed 1·58 % dietary Val had higher superoxide dismutase, catalase, lysozyme activities and IgM concentrations than fish fed other dietary Val levels. Fish fed 1·58 % dietary Val had higher expression of NF-E2-related factor 2 in head kidney than fish fed other dietary Val levels. Generally, the optimum dietary Val requirement for maximal growth of hybrid groupers was estimated to be 1·56 % of DM, corresponding to 3·16 % of dietary protein, and dietary Val levels affected growth, protein utilisation, immunity and antioxidant status in hybrid groupers.