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Hormone-sensitive lipase is one of the rate-determining enzymes in the hydrolysis of triglyceride, playing a crucial role in lipid metabolism. However, the role of HSL-mediated lipolysis in systemic nutrient homeostasis has not been intensively understood. Therefore, we used CRISPR/Cas9 technique and Hsl inhibitor (HSL-IN-1) to establish hsla-deficient (hsla-/-) and Hsl-inhibited zebrafish models, respectively. As a result, the hsla-/- zebrafish showed retarded growth and reduced oxygen consumption rate, accompanied with higher mRNA expression of the genes related to inflammation and apoptosis in liver and muscle. Furthermore, hsla-/- and HSL-IN-1 treated zebrafish both exhibited severe fat deposition, whereas their expressions of the genes related to lipolysis and fatty acid oxidation were markedly reduced. The thin layer chromatography results also showed that the dysfunction of Hsl changed the whole body lipid profile, including increasing the content of TG and decreasing the proportion of PL. In addition, the systemic metabolic pattern was remodeled in hsla-/- and HSL-IN-1 treated zebrafish. The dysfunction of Hsl lowered the glycogen content in liver and muscle, enhanced the utilization of glucose plus the expressions of glucose transporter and glycolysis genes. Besides, the whole-body protein content had significantly decreased in the hsla-/- and HSL-IN-1 treated zebrafish, accompanied with the lower activation of the mTOR pathway and enhanced protein and amino acid catabolism. Taken together, Hsl plays an essential role in energy homeostasis, and its dysfunction would cause the disturbance of lipid catabolism but enhanced breakdown of glycogen and protein for energy compensation.
Turbulence amplification and the large-scale coherent structures in shock wave/turbulent boundary layer interaction flows have been studied at length in previous research, while the direct association between these two flow features is still lacking. In the present study, the transport equation of turbulent kinetic energy spectra is derived and utilized to analyse the scale-by-scale energy budget across the interaction zone, enabling us to reveal the association between the genesis of the large-scale motions and the turbulence amplification. For the presently considered flow with incipient shock-induced separation, we identified in turbulent kinetic energy spectra distribution that the most energetic motions are converted from the near-wall small-scale motions to large-scale motions consisting of velocity streaks and cross-stream circulations as they go through the interaction zone. The amplification of streamwise velocity fluctuation is triggered first, resulting in the emergence of large-scale velocity streaks, which is attributed to the adverse pressure gradient, as indicated by the spectra of the production term. The energy carried by large-scale velocity streaks is transferred to other velocity components by the pressure-strain term, producing large-scale cross-stream circulations. When large-scale motions are convected downstream, their energy is transferred via turbulent cascade to smaller scales and dissipated by viscosity. The spanwise uniform fluctuations, reminiscent of the unsteadiness of the separation bubble, are contributed primarily by the inter-scale energy transfer from the finite spanwise scale motions.
To investigate spiritual care perceptions, spiritual well-being, and empathy, examine the correlations among spiritual care perceptions, spiritual well-being, and empathy, and explore the mediating role of spiritual well-being between other two variables of Chinese nursing students.
A cross-sectional design was implemented, and the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Checklist was used to ensure quality reporting of the study. A cluster sample of 2,718 nursing students was selected from 7 universities and colleges in China. The demographic characteristics questionnaire, the Chinese Version of the Spiritual Care-Giving Scale (C-SCGS), the Spiritual Health Scale Short Form (SHS-SF), and the Jefferson Scale of Physician Empathy-Nursing Student (JSPE-NS) were used. Descriptive statistics, correlation, and process plug-in mediation effect analyses were used to analyze the data.
The total score of spiritual care perceptions, spiritual well-being, and empathy were 173.83 ± 25.62, 98.74 ± 12.87, and 105.04 ± 21.34, respectively. Spiritual care perceptions were positively correlated with spiritual well-being (r = 0.617, p < 0.01) and empathy (r = 0.528, p < 0.01). And spiritual well-being played a partial mediating role between the other two variables (accounting for 28.1%).
Significance of results
Spiritual care perceptions, spiritual well-being, and empathy were quite moderate, which need in improving. It is suggested that nursing educators pay attention to the spiritual care education of nursing students, perfect the spiritual care education system, and take targeted measures according to nursing students’ individual personality traits and differences, improve their spiritual well-being and empathy in multiple ways, so as to improve their spiritual care perceptions and competence.
The codling moth Cydia pomonella is a major pest of global significance impacting pome fruits and walnuts. It threatens the apple industry in the Loess Plateau and Bohai Bay in China. Sterile insect technique (SIT) could overcome the limitations set by environmentally compatible area-wide integrated pest management (AW-IPM) approaches such as mating disruption and attract-kill that are difficult to suppress in a high-density pest population, as well as the development of insecticide resistance. In this study, we investigated the effects of X-ray irradiation (183, 366, 549 Gy) on the fecundity and fertility of a laboratory strain of C. pomonella, using a newly developed irradiator, to evaluate the possibility of X-rays as a replacement for Cobalt60 (60Co-γ) and the expanded future role of this approach in codling moth control. Results show that the 8th-day is the optimal age for irradiation of male pupae. The fecundity decreased significantly as the dosage of radiation increased. The mating ratio and mating number were not influenced. However, treated females were sub-sterile at a radiation dose of 183 Gy (20.93%), and were almost 100% sterile at a radiation dose of 366 Gy or higher. Although exposure to a radiation dose of 366 Gy resulted in a significant reduction in the mating competitiveness of male moths, our radiation biology results suggest that this new generation of X-ray irradiator has potential applications in SIT programs for future codling moth control.
Robot-assisted minimally invasive surgery (MIS) has shown tremendous advances over the traditional technique. A crucial challenge for developing a MIS robot is the kinematic design of the remote center-of-motion (RCM) mechanism. In this paper, a class of spatial RCM mechanism is analyzed. They are obtained by generating virtual parallelograms. The main process is to construct a line that passes through a fixed point under the mechanical constraint. The axis of the surgical tool is then constrained to parallel with that line. Hence, due to the geometrical feature of the parallel lines, the axis of the surgical tool will always pass through a fixed point, i.e., the RCM point. Due to the specially designed structure, the fixed point does not need to be physically belonging to the mechanism. The geometrical analysis method is employed to obtain the closed-form solution of the forward kinematics of the proposed mechanisms. Due to the high load capacity of parallel mechanism, the robots based on the proposed RCM mechanisms have promising applications as an external positioner to be used in robotic single-port surgeries.
This study evaluated the association between inflammatory diets as measured by the Dietary Inflammatory index (DII), inflammation biomarkers and the development of preeclampsia among the Chinese population. We followed the reporting guidelines of the Strengthening the Reporting of Observational Studies in Epidemiology statement for observational studies. A total of 466 preeclampsia cases aged over 18 years were recruited between March 2016 and June 2019, and 466 healthy controls were 1:1 ratio matched by age (±3 years), week of gestation (±1 week) and gestational diabetes mellitus. The energy-adjusted DII (E-DII) was computed based on dietary intake assessed using a seventy-nine item semiquantitative FFQ. Inflammatory biomarkers were analysed by ELISA kits. The mean E-DII scores were −0·65 ± 1·58 for cases and −1·19 ± 1·47 for controls (P value < 0·001). E-DII scores positively correlated with interferon-γ (rs = 0·194, P value = 0·001) and IL-4 (rs = 0·135, P value = 0·021). After multivariable adjustment, E-DII scores were positively related to preeclampsia risk (Ptrend < 0·001). The highest tertile of E-DII was 2·18 times the lowest tertiles (95 % CI = 1·52, 3·13). The odds of preeclampsia increased by 30 % (95 % CI = 18 %, 43 %, P value < 0·001) for each E-DII score increase. The preeclampsia risk was positively associated with IL-2 (OR = 1·07, 95 % CI = 1·03, 1·11), IL-4 (OR = 1·26, 95 % CI = 1·03, 1·54) and transforming growth factor beta (TGF-β) (OR = 1·17, 95 % CI = 1·06, 1·29). Therefore, proinflammatory diets, corresponding to higher IL-2, IL-4 and TGF-β levels, were associated with increased preeclampsia risk.
Little is known about the effects of dietary patterns on prevalent pre-eclampsia in Chinese population. This study aimed to investigate the associations between dietary patterns and the odds of pre-eclampsia among Chinese pregnant women. A 1:1 age- and gestational week-matched case–control study was conducted between March 2016 and February 2019. A total of 440 pairs of pre-eclampsia cases and healthy controls were included. Dietary intakes were assessed by a seventy-nine-item FFQ and subsequently grouped into twenty-eight distinct groups. Factor analysis using the principal component method was adopted to derive the dietary patterns. Conditional logistic regression was used to analyse the associations of dietary patterns with prevalent pre-eclampsia. We identified four distinct dietary patterns: high fruit-vegetable, high protein, high fat-grain and high salt-sugar. We found that high fruit-vegetable dietary pattern (quartile (Q)4 v. Q1, OR 0·71, 95 % CI 0·55, 0·92, Ptrend = 0·013) and high protein dietary pattern (Q4 v. Q1, OR 0·72, 95 % CI 0·54, 0·95, Ptrend = 0·011) were associated with a decreased odds of pre-eclampsia in Chinese pregnant women. Whereas high fat-grain dietary pattern showed a U-shaped association with pre-eclampsia, the lowest OR was observed in the third quartile (Q3 v. Q1, OR 0·75, 95 % CI 0·57, 0·98, Ptrend = 0·111). No significant association was observed for high salt-sugar dietary pattern. In conclusion, pregnancy dietary pattern characterised by high fruit-vegetable or high protein was found to be associated with a reduced odds of pre-eclampsia in Chinese pregnant women.
As one of the research hotspots in the field of rehabilitation robotics, the upper limb exoskeleton robot has been widely used in the field of rehabilitation. However, the existing methods cannot comprehensively and accurately reflect the motion state of patients, which may lead to overtraining and secondary injury of patients in the process of rehabilitation training. In this paper, an upper limb exoskeleton control method based on mixed perception model of motion intention and intensity is proposed, which is based on the 6 degree-of-freedom upper limb rehabilitation exoskeleton in the laboratory. First, the kinematic information and heart rate information in the rehabilitation process of patients are collected, corresponding to patients’ motion intention and motion intensity, and fused to obtain the mixed perception vector. Second, the motion perception model based on long short-term memory neural network is established to realize the prediction of upper limb motion trajectory of patients and compared with back-propagation neural network to prove its effectiveness. Finally, the control system is built, and both offline and online test of the control method proposed are implemented. The experimental results show that the method can achieve comprehensive motion state perception of patients, realize real-time and accurate prediction trajectory according to human motion intention and intensity. The average prediction accuracy is 95.3%, and predicted joint angle error is less than 5 degrees. Therefore, the control method based on mixed perception model has good robustness and universality, which provides a new method for the active control of upper limb exoskeleton.
This paper proposes an iterative algorithm to solve the inverse displacement for a hyper-redundant elephant’s trunk robot (HRETR). In this algorithm, each parallel module is regarded as a geometric line segment and point model. According to the forward approximation and inverse pose adjustment principles, the iteration process can be divided into forward and backward iteration. This iterative algorithm transforms the inverse displacement problem of the HRETR into the parallel module’s inverse displacement problem. Considering the mechanical joint constraints, multiple iterations are carried out to ensure that the robot satisfies the required position error. Simulation results show that the algorithm is effective in solving the inverse displacement problem of HRETR.
Evidence of couples’ BMI and its influence on birth weight is limited and contradictory. Therefore, this study aims to assess the association between couple’s preconception BMI and the risk of small for gestational age (SGA)/large for gestational age (LGA) infant, among over 4·7 million couples in a retrospective cohort study based on the National Free Pre-pregnancy Checkups Project (NFPCP) between December 1, 2013 and November 30, 2016 in China. Among the live births, 256,718 (5·44%) SGA events and 506,495 (10·73%) LGA events were documented, respectively. After adjusting for confounders, underweight men had significantly higher risk [OR 1·17 95%CI (1·15-1·19)] of SGA infants compared with men with normal BMI, while a significant and increased risk of LGA infants was obtained for overweight and obese men [OR 1·08 (95% CI: 1·06-1·09); OR 1·19 (95%CI 1·17-1·20)] respectively. The restricted cubic spline (RCS) result revealed a non-linearly decreasing dose-response relationship of paternal BMI (less than 22·64) with SGA. Meanwhile, a non-linearly increasing dose-response relationship of paternal BMI (more than 22·92) with LGA infants was observed. Moreover, similar results about the association between maternal preconception BMI and SGA/LGA infants were obtained. Abnormal preconception BMIs in either women or men were associated with increased risk of SGA/LGA infants, respectively. Overall, couple’s abnormal weight before pregnancy may be an important preventable risk factor for SGA/LGA infants.
Since the outbreak of coronavirus disease 2019 (COVID-19) in late 2019, it has evolved into a global pandemic that has become a substantial public health concern. COVID-19 is still causing a large number of deaths in several countries around the world because of the lack of effective treatment.
To systematically compare the outcomes of COVID-19 patients treated with integrated Chinese with western (ICW) medicine versus western medicine (WM) alone by pooling the data of published literature, and to determine if ICW treatment of COVID-19 patients has better clinical outcomes.
We searched PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), China Clinical Trial Registry, Chinese Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI) and Wanfang databases using keywords related to COVID-19, traditional Chinese medicine (TCM) and treatment effect. The search deadline was until 10 February 2021. All randomised controlled (RC) and non-randomised controlled (NRC) clinical trials of the ICW or WM treatment of COVID-19 patients were included. We analysed the effective rate, cure rate, exacerbation rate, turning negative rate of viral nucleic acid, remission rate and remission time of symptoms such as fever, cough, feebleness and chest computed tomography (CT) and the number of white blood cells (WBCs) and lymphocytes (LYM) of the COVID-19 patients. For qualitative and quantitative data, the ratio risk (RR) and weighted mean difference (WMD) were used as the indexes of the statistical analysis, respectively. RevMan 5.4 was used to perform meta-analyses and forest plots with the fixed-effects and random-effects models. Cochrane risk of bias tool (RoB 2.0) was used to assess the risk of bias in the included RC trials, whereas risk of bias in non-randomised studies of interventions was used to assess the risk of bias in NRC trials.
This research includes 16 studies with 1645 valid confirmed COVID-19 patients, among which 895 patients of the experimental group received ICW treatment whereas 750 patients of the control group received WM treatment. The outcomes were assessed in three aspects, that is, overall indicator, symptoms indicator and blood indicator, respectively, and the results showed that the ICW group had better treatment outcomes compared with the WM. Among the overall indicators, the ICW group displayed a higher effective rate (RR = 1.24, 95% confidence interval (CI): 1.16–1.33), clinical cure rate (RR = 1.27, 95% CI: 1.03–1.56) and lower exacerbation rate (RR = 0.36, 95% CI: 0.25–0.52), but no statistical difference was observed in the turning negative rate of viral nucleic acid (RR = 1.20, 95% CI: 0.78–1.85). Among the symptom indicators, the ICW group had a higher fever remission rate (RR = 1.24, 95% CI: 1.09–1.42), less fever remission time (WMD = −1.49, 95% CI: −1.85 to −1.12), a higher cough remission rate (RR = 1.38, 95% CI: 1.10–1.73) and a feebleness remission rate (RR = 1.45, 95% CI: 1.18–1.77), less cough remission time (WMD = −1.61, 95% CI: −2.35 to −0.87) and feebleness remission time (WMD = −1.50, 95% CI: −2.38 to −0.61) and better improvement in chest CT (RR = 1.19, 95% CI: 1.11–1.28). For blood indicator, the number of WBCs in the blood of patients of ICW group rebounded significantly (WMD = 0.35, 95% CI: 0.16–0.54), and the recovery of LYM in the blood was more obvious (WMD = 0.23, 95% CI: 0.06–0.40).
The results of this study show that the outcomes in COVID-19 patients treated by the ICW is better than those treated by the WM treatment alone, suggesting that WM and TCM can be complementary in the treatment of COVID-19.
This paper develops the conceptual design and error analysis of a cable-driven parallel robot (CDPR). The earlier error analysis of CDPRs generally regarded the cable around the pulley as a center point and neglected the radius of the pulleys. In this paper, the conceptual design of a CDPR with pulleys on its base platform is performed, and an error mapping model considering the influence of radius of the pulleys for the CDPR is established through kinematics analysis and a full matrix complete differential method. Monte Carlo simulation is adopted to deal with the sensitivity analysis, which can directly describe the contribution of each error component to the total orientation error of the CDPR by virtue of the error modeling. The results show that the sensitivity coefficients of pulleys’ geometric errors and geometric errors of the cables are relatively larger, which confirms that the cable length errors and pulleys’ geometric errors should be given higher priority in design and processing.
To investigate the association between the Metabolic Score for Visceral Fat (METS-VF) and risk of type 2 diabetes mellitus (T2DM) and compare the predictive value of the METS-VF for T2DM incidence with other obesity indices in Chinese people. A total of 12 237 non-T2DM participants aged over 18 years from the Rural Chinese Cohort Study of 2007–2008 were included at baseline and followed up during 2013–2014. The cox proportional hazards regression was used to calculate hazard ratios (HR) and 95 % CI for the association between baseline METS-VF and T2DM risk. Restricted cubic splines were used to model the association between METS-VF and T2DM risk. Area under the receiver operating characteristic curve (AUC) analysis was used to evaluate the ability of METS-VF to predict T2DM incidence. During a median follow-up of 6·01 (95 % CI 5·09, 6·06) years, 837 cases developed T2DM. After adjusting for potential confounding factors, the adjusted HR for the highest v. lowest METS-VF quartile was 5·97 (95 % CI 4·28, 8·32), with a per 1-sd increase in METS-VF positively associated with T2DM risk. Positive associations were also found in the sensitivity and subgroup analyses, respectively. A significant nonlinear dose–response association was observed between METS-VF and T2DM risk for all participants (Pnonlinearity = 0·0347). Finally, the AUC value of METS-VF for predicting T2DM was largest among six indices. The METS-VF may be a reliable and applicable predictor of T2DM incidence in Chinese people regardless of sex, age or BMI.
The effect of vitamin D (VD) on the risk of preeclampsia (PE) is uncertain. Few of previous studies focused on the relationship between dietary VD intake and PE risk. Therefore, we conducted this 1:1 matched case–control study to explore the association of dietary VD intake and serum VD concentrations with PE risk in Chinese pregnant women. A total of 440 pairs of participants were recruited during March 2016 to June 2019. Dietary information was obtained using a seventy-eight-item semi-quantitative FFQ. Serum concentrations of 25(OH)D2 and 25(OH)D3 were measured by liquid chromatography–tandem MS. Multivariate conditional logistic regression was used to estimate OR and 95 % CI. Restricted cubic splines (RCS) were plotted to evaluate the dose–response relationship of dietary VD intake and serum VD concentrations with PE risk. Compared with the lowest quartile, the OR of the highest quartile were 0·45 (95 % CI 0·29, 0·71, Ptrend = 0·001) for VD dietary intake and 0·26 (95 % CI 0·11, 0·60, Ptrend = 0·003) for serum levels after adjusting for confounders. In addition, the RCS analysis suggested a reverse J-shaped relationship between dietary VD intake and PE risk (P-nonlinearity = 0·02). A similar association was also found between serum concentrations of total 25(OH)D and PE risk (P-nonlinearity = 0·02). In conclusion, this study provides evidence that higher dietary intake and serum levels of VD are associated with the lower risk of PE in Chinese pregnant women.
This paper investigates the design and development of bio-inspired suture pins that would reduce the insertion force and thereby reducing the pain in the patients. Inspired by kingfisher's beak and porcupine quills, the conceptual design of the suture pin is developed by using a unique ideation methodology that is proposed in this research. The methodology is named as Domain Integrated Design, which involves in classifying bio-inspired structures into various domains. There is little work done on such bio-inspired multifunctional aspect. In this research we have categorized the vast biological functionalities into domains namely, cellular structures, shapes, cross-sections, and surfaces. Multi-functional bio-inspired structures are designed by combining different domains. In this research, the hypothesis is verified by simulating the total deformation of tissue and the needle at the moment of puncture. The results show that the bio-inspired suture pin has a low deformation on the tissue at higher velocities at the puncture point and low deformation in its own structure when an axial force (reaction force) is applied to its tip. This makes the design stiff and thus require less force of insertion.
The particle–particle (PP) model has a growing number of applications in plasma simulations, because of its high accuracy of solving Coulomb collisions. One of the main issues restricting the practical use of the PP model is its large computational cost, which is now becoming acceptable thanks to state-of-art parallel computing techniques. Another issue is the singularity that occurs when two particles are too close. The most effective approach of avoiding the singularity would be to simulate particles with only like charges plus a neutralizing field, such that the short-range collisions are equivalent to those of using unlike charges. In this paper, we introduce a way of adding the neutralizing field by using the analytical solution of the electric field in the domain filled with uniformly distributed charges, for applications with homogeneous and quasi-neutral plasmas under a reflective boundary condition. Two most common Cartesian domain geometries, cubic and spherical, are considered. The model is verified by comparing simulation results with an analytical solution of an electron–ion temperature relaxation problem, and a corresponding simulation using unlike charges. In addition, it is found that a PP simulation using like charges can achieve a significant speed-up of 100 compared with a corresponding simulation using unlike charges, due to the capability of using larger time steps while maintaining the same energy conservation.
A single-layer ultra-wideband (UWB) stop-band frequency selective surface (FSS) has several advantages in wireless systems, including a simple design, low debugging complexity, and an appropriate thickness. This study proposes a miniaturized UWB stop-band FSS design. The proposed FSS structure consists of a square-loop and metalized vias that are arranged on a single layer substrate; it has an excellent angle and polarization-independent characteristics. At an incident angle of 60°, the polarization response frequencies of the transverse electric and magnetic modes only shifted by 0.003 f0 and 0.007 f0, respectively. The equivalent circuit models of the square-loop and metallized vias structure are analysed and the accuracy of the calculation is evaluated by comparing the electromagnetic simulation. The 20 × 20 array constitutes an FSS reflector with a unit size of 4.2 mm × 4.2 mm (less than one-twentieth of the wavelength of 3 GHz), which realizes an UWB quasi-constant gain enhancement (in-band flatness is <0.5 dB). Finally, the simulation results were verified through sample processing and measurement; consistent results were obtained. The FSS miniaturization design method proposed in this study could be applied to the design of passband FSS (complementary structure), antennas and filters, among other applications.