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The Palaeo-Mesozoic geodynamic evolution of the Tangjia–Sumdo accretionary complex belt, which separates the North and South Lhasa Terrane, remains controversial. Moreover, the lack of geological records restricts the understanding of the evolution of the Sumdo Palaeo-Tethys Ocean from the middle Permian until the middle Triassic. Here we present zircon U–Pb geochronology, whole-rock geochemistry and Sr–Nd–Hf isotopic compositions of the Yeqing gabbro. Zircon U–Pb geochronology yields ages from 254 ± 1 to 249 ± 1 Ma. In situ Hf isotopic analyses yield ϵHf(t) values of −0.2 to +6.3. These samples have high TiO2 (3.69 wt %) and P2O5 (0.78 wt %) contents, with typical patterns like ocean island basalt (OIB). Besides, they are classified as high-Nb basalts (HNBs) based on the high content of Nb (45.3–113.5 ppm). Whole-rock Sr–Nd isotopic compositions are similar to OIB, with initial 87Sr/86Sr of 0.7047–0.7054, 143Nd/144Nd of 0.512526–0.512647 and ϵNd(t) of 0.3–2.7. These signatures suggest that the Yeqing gabbro is mainly derived from low-degree melting of the garnet lherzolite mantle. Based on field observations of HNBs intruding into the continental margin and their geochemical characteristics, we infer that the Yeqing gabbro was generated in a subduction environment. Combined with the regional geology of the subduction environment and the evolution of oceanic islands in the Sumdo Palaeo-Tethys Ocean, we propose that the Yeqing gabbro may represent a product of the asthenosphere upwelling through a slab window produced by subduction of seismic ridge in the Sumdo Palaeo-Tethys Ocean, called plume – subduction-zone interaction, during the late Permian to early Triassic.
Instrument delivery is critical part in vascular intervention surgery. Due to the soft-body structure of instruments, the relationship between manipulation commands and instrument motion is non-linear, making instrument delivery challenging and time-consuming. Reinforcement learning has the potential to learn manipulation skills and automate instrument delivery with enhanced success rates and reduced workload of physicians. However, due to the sample inefficiency when using high-dimensional images, existing reinforcement learning algorithms are limited on realistic vascular robotic systems. To alleviate this problem, this paper proposes discrete soft actor-critic with auto-encoder (DSAC-AE) that augments SAC-discrete with an auxiliary reconstruction task. The algorithm is applied with distributed sample collection and parameter update in a robot-assisted preclinical environment. Experimental results indicate that guidewire delivery can be automatically implemented after 50k sampling steps in less than 15 h, demonstrating the proposed algorithm has the great potential to learn manipulation skill for vascular robotic systems.
With the rapid development of the national economy, the demand for electricity is also growing. Thermal power generation accounts for the highest proportion of power generation, and coal is the most commonly used combustion material. The massive combustion of coal has led to serious environmental pollution. It is significant to improve energy conversion efficiency and reduce pollutant emissions effectively. In this paper, an extreme learning machine model based on improved Kalman particle swarm optimization (ELM-IKPSO) is proposed to establish the boiler combustion model. The proposed modeling method is applied to the combustion modeling process of a 300 MWe pulverized coal boiler. The simulation results show that compared with the same type of modeling method, ELM-IKPSO can better predict the boiler thermal efficiency and NOx emission concentration and also show better generalization performance. Finally, multi-objective optimization is carried out on the established model, and a set of mutually non-dominated boiler combustion solutions is obtained.
To investigate the association between folate levels and the risk of gestational diabetes mellitus (GDM) risk during the whole pregnancy.
Design:
In this retrospective cohort study of pregnant women, serum folate levels were measured before 24 gestational weeks (GW). GDM was diagnosed between 24th and 28th GW based on the criteria of the International Association of Diabetes and Pregnancy Study Groups. General linear models were performed to examine the association of serum folate with plasma glucose (i.e. linear regressions) and risk of GDM (i.e. log-binomial regressions) after controlling for confounders. Restricted cubic spline regression was conducted to test the dosage–response relationship between serum folate and the risk of GDM.
Setting:
A sigle, urban hospital in Shanghai, China.
Participants:
A total of 42 478 women who received antenatal care from April 2013 to March 2017 were included.
Results:
Consistent positive associations were observed between serum folate and plasma glucose levels (fasting, 1-h, 2-h). The adjusted relative risks (RR) and 95 % CI of GDM across serum folate quartiles were 1·00 (reference), 1·15 (95 % CI (1·04, 1·26)), 1·40 (95 % CI (1·27, 1·54)) and 1·54 (95 % CI (1·40, 1·69)), respectively (P-for-trend < 0·001). The positive association between serum folate and GDM remained when stratified by vitamin B12 (adequate v. deficient groups) and the GW of serum folate measurement (≤13 GW v. >13 GWs)
Conclusions:
The findings of this study may provide important evidence for the public health and clinical guidelines of pregnancy folate supplementation in terms of GDM prevention.
Investigations illustrate that the Internet of Things (IoT) can save costs, increase efficiency, improve quality, and provide data-driven preventative maintenance services. Intelligent sensors, dependable connectivity, and complete integration are essential for gathering real-time information. IoT develops home appliances for improved customer satisfaction, personalization, and enhanced big data analytics as a crucial Industry 4.0 enabler. Because the product design process is an important part of controlling manufacturing, there are constant attempts to improve and minimize product design time. Utilizing a hybrid algorithm, this research provides a novel method to schedule design products in production management systems to optimize energy usage and design time (combined particle optimization algorithm and shuffled frog leaping algorithm). The issue with particle optimization algorithms is that they might become stuck in local optimization and take a long time to converge to global optimization. The strength of the combined frog leaping algorithm local searching has been exploited to solve these difficulties. The MATLAB programming tool is used to simulate the suggested technique. The simulation findings were examined from three perspectives: energy usage, manufacturing time, and product design time. According to the findings, the recommended strategy performed better in minimizing energy use and product design time. These findings also suggest that the proposed strategy has a higher degree of convergence when discovering optimal solutions.
This study aimed to evaluate the efficacy and safety of high-frequency oscillation ventilation combined with intermittent mandatory ventilation in infants with acute respiratory distress syndrome after congenital heart surgery.
Methods:
We retrospectively analysed the clinical data of 32 infants who were ventilated due to acute respiratory distress syndrome after congenital heart surgery between January, 2020 and January, 2022. We adopted high-frequency oscillation ventilation combined with intermittent mandatory ventilation as the rescue ventilation mode for infants who were failing conventional mechanical ventilation.
Results:
After rescue high-frequency oscillation ventilation combined with intermittent mandatory ventilation, the dynamic compliance (Cdyn), PaO2 and PaO2/FiO2 ratio of the infants improved compared with conventional mechanical ventilation (p < 0.05). Moreover, high-frequency oscillation ventilation combined with intermittent mandatory ventilation resulted in a significant decrease in arterial-alveolar oxygen difference (AaDO2), FiO2, and oxygenation index (p < 0.05). No significant effect on haemodynamic parameters was observed. Moreover, no serious complications occurred in the two groups.
Conclusion:
Rescue high-frequency oscillation ventilation combined with intermittent mandatory ventilation significantly improved oxygenation in infants who failed conventional mechanical ventilation for acute respiratory distress syndrome after congenital heart surgery. Thus, this strategy is considered safe and feasible. However, further studies must be conducted to confirm the efficacy and safety of high-frequency oscillation ventilation combined with intermittent mandatory ventilation as a rescue perioperative respiratory support strategy for CHD.
Late Palaeozoic igneous rock associations in response to subduction, accretion, and final closure of the eastern Palaeo-Asian Ocean play a significant role in understanding the geodynamic evolution of the southeastern Central Asian Orogenic Belt. Previous studies have identified a Permian arc magmatic belt associated with the southward-dipping subduction of the eastern Palaeo-Asian Ocean along the Solonker–Changchun suture zone. The genetic mechanism and associated geodynamic settings are of great importance in deciphering the evolution of the eastern Palaeo-Asian Ocean. This paper presents zircon U–Pb–Hf isotope and whole-rock geochemical analyses for a suite of magmatic rocks including the early Permian diorite porphyrites (ca. 281.0 Ma), andesites (ca. 276 Ma) and rhyolites (ca. 275 Ma) in the Kulun region. The diorite porphyrites and andesites have high SiO2 and total alkali contents, and low MgO contents and Mg no. values, with enrichments in large ion lithophile elements and depletions in high-field-strength elements. These geochemical characteristics, together with low-Sr and high-Yb contents, a weak concave-upward shape of middle rare earth elements and negative Eu anomalies, suggest that these intermediate igneous rocks were generated by partial melting of amphibolitic lower crust at a crustal depth of 30–40 km. The rhyolites have heterogeneous isotopic compositions, with ϵHf(t) values and TDM2 ages of –20.8 to +0.5 and 3578∼1494 Ma, implying that they were likely derived from partial melting of a mixed source dominated by recycled ancient crust with minor juvenile crustal materials. The rhyolites show potassic affinity with relatively high K2O and very low Na2O, which was attributed to liquid immiscibility of felsic magma and subsequent limited fractional crystallization of plagioclase. The regional igneous associations, metamorphic events, and coeval sedimentary rocks along the Solonker–Changchun suture zone indicate that the early Permian igneous rocks were formed in an active continental arc environment in response to southward subduction of the eastern Palaeo-Asian Ocean.
This paper investigates the impact of the abolition of the civil service exam on local governance in early twentieth-century China. Before the abolition, local elites collected surtaxes that financed local public goods, but they were supervised by the state and could lose candidacy for higher status if they engaged in corrupt behavior. This prospect of upward mobility (POUM) gave them incentives to behave well, which the abolition of the exam removed. Using anti-elite protests as a proxy for the deterioration of local governance, we find that prefectures with a higher POUM experienced more incidents of anti-elite protests after the abolition.
We report a laboratory study on the scattering, energy dissipation and mean flow induced by internal gravity waves incident upon slopes with varying surface roughness. The experiment was performed in a rectangular box filled with thermally stratified water. The roughness of the slope surface, $\lambda$, defined as the height of a roughness element over its base width, and the off-criticality $\gamma =(\alpha -\beta )/\beta$, with $\alpha$ and $\beta$ being the angles of the incident wave and the slope, are used as two control parameters. The distribution of energy dissipation in the direction normal to the slope is found to be more uniform in the rough surface cases. Counter-intuitively, both the maximum value in the dissipation profile and the total energy dissipation near the slope are reduced by surface roughness under most circumstances. The measured peak width (the full width at half-maximum of the peaks) of the dissipation profile is found to be broadened significantly in the rough surface cases. We also observed that there exists a non-zero optimal off-criticality ($\gamma =0.17$ for the present measurement resolution) for the normalized average dissipation and total dissipation, which may be due to the strongest wave energy near the slope at this $\gamma$. Unlike surface roughness, the off-criticality has a small effect on the distribution of energy dissipation. Moreover, surface roughness is also found to change the structure of the scattering-induced mean flow and enhance its strength. The present study provides new perspectives on how the surface roughness on topographic features influences energy dissipation.
Accumulating evidence suggests that supplementation of omega-3 polyunsaturated fatty acids (ω−3 PUFAs) was associated with reduction in risk of major cardiovascular events. This meta-analysis was to systematically evaluate whether daily supplementation and accumulated intake of ω−3 PUFAs is associated with improved left ventricular (LV) remodeling in patients with chronic heart failure (CHF). Articles were obtained from Pubmed, Clinical key and Web of Science from inception to January 1 in 2021, and a total of 12 trials involving 2162 participants were eligible for inclusion. The sources of study heterogeneity were explained by I2 statistic and subgroup analysis. Compared with placebo groups, ω−3 PUFAs supplementation improved LV ejection fraction (LVEF) (11 trials, 2112 participants, WMD=2.52, 95%CI 1.25 to 3.80, I2=87.8%) and decreased LV end-systolic volume (LVESV) (5 studies, 905 participants, WMD=−3.22, 95%CI −3.67 to −2.77, I2=0.0%) by using the continuous variables analysis. Notably, the high accumulated ω−3 PUFAs dosage groups (≥600g) presented a prominent improvement in LVEF, while the low and middle accumulated dosage (≤300g and 300-600g) showed no effects on LVEF. In addition, ω−3 PUFAs supplementation decreased the levels of pro-inflammatory mediators including tumor necrosis factor−α (TNF-α), interleukin-6 (IL-6) and hypersensitive-c-reactive protein (Hs-CRP). Therefore, the present meta-analysis demonstrated that ω−3 PUFAs consumption was associated with a substantial improvement of LV function and remodeling in patients subjected to CHF. The accumulated dosage of ω-3 PUFAs intake is vital for its cardiac protective role.
We aimed to investigate the coronavirus disease 2019 (COVID-19)-related knowledge and practices of cancer patients and to assess their anxiety- and depression-related to COVID-19 during the early surge phase of the pandemic.
Methods:
An online questionnaire survey of cancer patients was conducted from February 10-29, 2020. Knowledge and practices related to COVID-19 were assessed using a custom-made questionnaire. The Hospital Anxiety and Depression Scale was used to assess the presence of anxiety and depression, with scores beyond 7 indicating anxiety or depressive disorder. Univariate and multiple linear regression analyses were used to identify the high-risk groups according to the level of knowledge, practices, anxiety, and depression scores.
Results:
A total of 341 patients were included. The rate of lower level of knowledge and practices was 49.9% and 18.8%, respectively. Education level of junior high school degree or lower showed a significant association with lower knowledge score (β: −3.503; P < 0.001) and lower practices score (β: −2.210; P < 0.001) compared to the education level of college degree and above. The prevalence of anxiety and depression among the respondents was 17.6% and 23.2%, respectively. A higher depression score was associated with older age, marital status of the widowed, and lower level of education, knowledge score, and practices score (P < 0.05).
Conclusions:
Targeted COVID-19-related education interventions are required for cancer patients with a lower level of knowledge to help improve their practices. Interventions are also required to address the anxiety and depression of cancer patients.
We present a numerical study on how tidal force and topography influence flow dynamics, transport and mixing in horizontal convection. Our results show that local energy dissipation near topography will be enhanced when the tide is sufficiently strong. Such enhancement is related to the height of the topography and increases as the tidal frequency $\omega$ decreases. The global dissipation is found to be less sensitive to the changes in $\omega$ when the latter becomes small and asymptotically approaches a constant value. We interpret the behaviour of the dissipation as a result of the competition among the dominant forces in the system. According to which mechanism prevails, the flow state of the system can be divided into three regimes, which are the buoyancy-, tide- and drag-control regimes. We show that the mixing efficiency $\eta$ for different tidal energy and topography height can be well described by a universal function $\eta \approx \eta _{HC}/(1+\mathcal {R})$, where $\eta _{HC}$ is the mixing efficiency in the absence of tide and $\mathcal {R}$ is the ratio between tidal and available potential energy inputs. With this, one can also determine the dominant mechanism at a certain ocean region. We further derive a power law relationship connecting the mixing coefficient and the tidal Reynolds number.
Wood vinegar, a product of pyrolysis, can induce phytotoxicity on plants when applied at an adequate rate and concentration. The objective of this research was to investigate wood vinegar obtained from the pyrolysis of apple tree branches for weed control in dormant zoysiagrass. In environment-controlled growth chambers, white clover visual injury and shoot mass reduction were evaluated and compared to the nontreated control after wood vinegar application at 1,000, 2,000, or 4,000 L ha−1 under 10 C or 30 C temperature conditions. Averaged across rates, wood vinegar rapidly desiccated white clover and caused 83% and 71% visual injury at 10 C and 30 C, respectively, at 1 d after treatment (DAT). Averaged across temperatures, wood vinegar at 1,000, 2,000, and 4,000 L ha−1 reduced white clover shoot mass by 56%, 81%, and 98% from the nontreated control at 10 DAT, respectively. In field experiments, weed control increased as wood vinegar rates increased from 1,000 to 5,000 L ha−1 in dormant zoysiagrass. The effective application dose of wood vinegar required to provide 90% control (ED90) of annual fleabane, Persian speedwell, and white clover was determined to be 2,450, 2,300, and 4,020 L ha−1, respectively, at 2 wk after treatment. Turf quality did not differ among the wood vinegar treatments and the nontreated control when zoysiagrass completely recovered from dormancy. Overall, results illustrate that wood vinegar resulting from the pyrolysis of apple tree branches can be used as a nonselective herbicide in dormant turfgrass, offering a new nonsynthetic herbicide option for weed control in managed turf.
Noncompressible torso hemorrhage (NCTH) is a major challenge in prehospital bleeding control and is associated with high mortality. This study was performed to estimate medical knowledge and the perceived barriers to information acquisition among health-care workers (HCWs) regarding NCTH in China.
Methods:
A self-administered and validated questionnaire was distributed among 11 WeChat groups consisting of HCWs engaged in trauma, emergency, and disaster rescue.
Results:
A total of 575 HCWs participated in this study. In the knowledge section, the majority (87.1%) denied that successful hemostasis could be obtained by external compression. Regarding attitudes, the vast majority of HCWs exhibited positive attitudes toward the important role of NCTH in reducing prehospital preventable death (90.4%) and enthusiasm for continuous learning (99.7%). For practice, fewer than half of HCWs (45.7%) had heard of NCTH beforehand, only a minority (14.3%) confirmed they had attended relevant continuing education, and 16.3% HCWs had no access to updated medical information. The most predominant barrier to information acquisition was the lack of continuing training (79.8%).
Conclusions:
Knowledge and practice deficiencies do exist among HCWs. Obstacles to update medical information warrant further attention. Furthermore, education program redesign is also needed.
Chronic inflammation exerts pleiotropic effects in the aetiology and progression of chronic obstructive pulmonary disease (COPD). Glucosamine is widely used in many countries and may have anti-inflammatory properties. We aimed to prospectively evaluate the association of regular glucosamine use with incident COPD risk and explore whether such association could be modified by smoking in the UK Biobank cohort, which recruited more than half a million participants aged 40–69 years from across the UK between 2006 and 2010. Cox proportional hazards models with adjustment for potential confounding factors were used to calculate hazard ratios (HR) as well as 95 % CI for the risk of incident COPD. During a median follow-up of 8·96 years (interquartile range 8·29–9·53 years), 9016 new-onset events of COPD were documented. We found that the regular use of glucosamine was associated with a significantly lower risk of incident COPD with multivariable adjusted HR of 0·80 (95 % CI, 0·75, 0·85; P < 0·001). When subgroup analyses were performed by smoking status, the adjusted HR for the association of regular glucosamine use with incident COPD were 0·84 (0·73, 0·96), 0·84 (0·77, 0·92) and 0·71 (0·62, 0·80) among never smokers, former smokers and current smokers, respectively. No significant interaction was observed between glucosamine use and smoking status (Pfor interaction = 0·078). Incident COPD could be reduced by 14 % to 84 % through a combination of regular glucosamine use and smoking cessation.
Prolonged sitting in a fixed or constrained position exposes aircraft passengers to long-term static loading of their bodies, which has deleterious effects on passengers’ comfort throughout the duration of the flight. The previous studies focused primarily on office and driving sitting postures and few studies, however, focused on the sitting postures of passengers in aircraft. Consequently, the aim of the present study is to detect and recognize the sitting postures of aircraft passengers in relation to sitting discomfort. A total of 24 subjects were recruited for the experiment, which lasted for 2 h. Furthermore, a total of 489 sitting postures were extracted and the pressure data between subjects and seat was collected from the experiment. After the detection of sitting postures, eight types of sitting postures were classified based on key parts (trunk, back, and legs) of the human bodies. Thereafter, the eight types of sitting postures were recognized with the aid of pressure data of seat pan and backrest employing several machine learning methods. The best classification rate of 89.26% was obtained from the support vector machine (SVM) with radial basis function (RBF) kernel. The detection and recognition of the eight types of sitting postures of aircraft passengers in this study provided an insight into aircraft passengers’ discomfort and seat design.
We conducted the first detailed mineral magnetic investigation of more than nine loess–paleosol couplets of the composite Titel-Stari Slankamen loess section in Serbia, which provides one of the longest and most complete terrestrial record of paleoclimatic changes in Europe since ~1.0 Ma. The results show that the ferrimagnetic mineral assemblage of the loess units is dominated by partially oxidized multidomain (MD) and pseudo-single domain (PSD) magnetite; however, with an increasing degree of pedogenesis, the eolian contribution is gradually masked by pedogenic superparamagnetic(SP) and single-domain (SD) ferrimagnets (mainly maghemite). The overall consistency of ferrimagnetic grain-size parameters indicates an absence of dissolution of the fine-grained ferrimagnetic fraction despite changes in climate regime over the past 1.0 Ma. The variations of normalized dJ/dT@120K and normalized χheating@530°C reflect a long-term stepwise increase in aridity during glacials with a major step at ~0.6–0.5 Ma, over the last 1.0 Ma. Overall, the results provide an improved basis for the future use of the magnetic properties of Serbian loess deposits for paleoclimatic reconstruction.