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Following indirect-drive experiments which demonstrated promising performance for low convergence ratios (below 17), previous direct-drive simulations identified a fusion-relevant regime which is expected to be robust to hydrodynamic instability growth. This paper expands these results with simulated implosions at lower energies of 100 and 270 kJ, and ‘hydrodynamic equivalent’ capsules which demonstrate comparable convergence ratio, implosion velocity and in-flight aspect ratio without the need for cryogenic cooling, which would allow the assumptions of one-dimensional-like performance to be tested on current facilities. A range of techniques to improve performance within this regime are then investigated, including the use of two-colour and deep ultraviolet laser pulses. Finally, further simulations demonstrate that the deposition of electron energy into the hotspot of a low convergence ratio implosion through auxiliary heating also leads to significant increases in yield. Results include break even for 1.1 MJ of total energy input (including an estimated 370 kJ of short-pulse laser energy to produce electron beams for the auxiliary heating), but are found to be highly dependent upon the efficiency with which electron beams can be created and transported to the hotspot to drive the heating mechanism.
The vortex dynamics in a stratified environment is of fundamental importance in various flow systems, however, the mechanism of successive vortex–interface interactions remains not fully understood. This study investigates synthetic jet vortex rings impinging on a water–oil interface by experiment and numerical simulation. Two cases in the laminar and transitional regimes are concerned with the Froude number (Fr) of 0.35 and 0.82, respectively. The vortex rings for the two cases follow a similar evolution with three distinct stages, including vortex free-travel, vortex–interface interaction and vortex stretching. As products of the vortex–interface interaction, the secondary vortex rings are baroclinically generated in both water and oil followed by the formation of hairpin vortices through azimuthal deformation. Distinguished from an isolated vortex–interface interaction, complex interactions occur between the primary vortex ring and hairpin vortices, which can enhance the vortex ring instability in existence of the stratification for the laminar case. However, the vortex ring instability for the transitional case can develop earlier due to nonlinear effects with increasing Reynolds number. The spatio-temporal properties of the interface deformation and interfacial waves are analysed. The maximum penetration height of vortex rings scales with Fr2 as that for the isolated situation. Particularly, the transitional case is found to produce destabilization of the interfacial waves at a further radial location. The mechanism is revealed by connecting the dynamics of the vortex and the interface, which can be attributed to the radial development of perturbances stemming from the vortex ring instability under strong vortex–interface interaction.
Low molecular weight glutenin subunits (LWM-GSs) play a crucial role in determining wheat flour processing quality. In this work, 35 novel LMW-GS genes (32 active and three pseudogenes) from three Aegilops umbellulata (2n = 2x = 14, UU) accessions were amplified by allelic-specific PCR. We found that all LMW-GS genes had the same primary structure shared by other known LMW-GSs. Thirty-two active genes encode 31 typical LMW-m-type subunits. The MZ424050 possessed nine cysteine residues with an extra cysteine residue located in the last amino acid residue of the conserved C-terminal III, which could benefit the formation of larger glutenin polymers, and therefore may have positive effects on dough properties. We have found extensive variations which were mainly resulted from single-nucleotide polymorphisms (SNPs) and insertions and deletions (InDels) among the LMW-GS genes in Ae. umbellulata. Our results demonstrated that Ae. umbellulata is an important source of LMW-GS variants and the potential value of the novel LMW-GS alleles for wheat quality improvement.
Recently, the nature of viscoelastic drag-reducing turbulence (DRT), especially the maximum drag reduction (MDR) state, has become a focus of controversy. It has long been regarded as polymer-modulated inertial turbulence (IT), but is challenged by the newly proposed concept of elasto-inertial turbulence (EIT). This study is to repicture DRT in parallel plane channels by introducing dynamics of EIT through statistical, structural and budget analysis for a series of flow regimes from the onset of drag reduction to EIT. Some underlying mechanistic links between DRT and EIT are revealed. Energy conversion between velocity fluctuations and polymers as well as pressure redistribution effects are of particular concern, based on which a new energy self-sustaining process (SSP) of DRT is repictured. The numerical results indicate that at low Reynolds number ($Re$), weak IT flow is replaced by a laminar regime before the barrier of EIT dynamics is established with the increase of elasticity, whereas, at moderate $Re$, EIT-related SSP can get involved and survive from being relaminarized. This further explains the reason why relaminarization phenomenon is observed for low $Re$ while the flow directly enters MDR and EIT at moderate $Re$. Moreover, with the proposed energy picture, the newly discovered phenomenon that streamwise velocity fluctuations lag behind those in the wall-normal direction can be well explained. The repictured SSP certainly justifies the conjecture that IT nature is gradually replaced by that of EIT in DRT with the increase of elasticity.
In this paper, we propose a sparse point-plane odometry used in structured environments. Compared to a point-based odometry, we add additional planar constraints into the process of optimization, making the results more reliable. A novel grid-based plane detection algorithm is proposed to cluster sparse points in the same planes. Then, the planes are parameterized by inverse normal and take part in the windowed optimization. By reducing the size of Hessian Matrix, the process of optimization converges faster. Compared to the original point-based odometry, the proposed method performs better on both robustness and efficiency in structured environments.
This study investigates the dynamics of low-viscosity nanodroplets impacting surfaces with static contact angles from θ = 73° to 180° via molecular dynamics (MD) simulations. Two typical morphologies of impacting nanodroplets are observed at the maximum spreading state, a Hertz-ball-like in a low-Weber-number range and a thin-film-like in a high-Weber-number range. Only inertial and capillary forces dominate the impact for the former, whereas viscous force also becomes dominant for the latter. Regardless of morphologies at the maximum spreading state, the ratio of spreading time to contact time always remains constant on an ideal superhydrophobic surface with θ = 180°. With the help of different kinematic approximations of the spreading time and scaling laws of the contact time, scaling laws of the maximum spreading factor ${\beta _{max}}\sim W{e^{1/5}}$ in the low-Weber-number range (capillary regime) and ${\beta _{max}}\sim W{e^{2/3}}R{e^{ - 1/3}}$ (or ${\beta _{max}}\sim W{e^{1/2}}O{h^{1/3}}$) in the high-Weber-number range (cross-over regime) are obtained. Here, We, Re, and Oh are the Weber number, Reynolds number, and Ohnesorge number, respectively. Although the scaling laws are proposed only for the ideal superhydrophobic surface, they are tested valid for θ over 73° owing to the ignorable zero-velocity spreading effect. Furthermore, combining the two scaling laws leads to an impact number, $W{e^{3/10}}O{h^{1/3}} = 2.1$. This impact number can be used to determine whether viscous force is ignorable for impacting nanodroplets, thereby distinguishing the capillary regime from the cross-over regime.
Gut microbiome and dietary patterns have been suggested to be associated with depression/anxiety. However, limited effort has been made to explore the effects of possible interactions between diet and microbiome on the risks of depression and anxiety.
Methods
Using the latest genome-wide association studies findings in gut microbiome and dietary habits, polygenic risk scores (PRSs) analysis of gut microbiome and dietary habits was conducted in the UK Biobank cohort. Logistic/linear regression models were applied for evaluating the associations for gut microbiome-PRS, dietary habits-PRS, and their interactions with depression/anxiety status and Patient Health Questionnaire (PHQ-9)/Generalized Anxiety Disorder-7 (GAD-7) score by R software.
Results
We observed 51 common diet–gut microbiome interactions shared by both PHQ score and depression status, such as overall beef intake × genus Sporobacter [hurdle binary (HB)] (PPHQ = 7.88 × 10−4, Pdepression status = 5.86 × 10−4); carbohydrate × genus Lactococcus (HB) (PPHQ = 0.0295, Pdepression status = 0.0150). We detected 41 common diet–gut microbiome interactions shared by GAD score and anxiety status, such as sugar × genus Parasutterella (rank normal transformed) (PGAD = 5.15 × 10−3, Panxiety status = 0.0347); tablespoons of raw vegetables per day × family Coriobacteriaceae (HB) (PGAD = 6.02 × 10−4, Panxiety status = 0.0345). Some common significant interactions shared by depression and anxiety were identified, such as overall beef intake × genus Sporobacter (HB).
Conclusions
Our study results expanded our understanding of how to comprehensively consider the relationships for dietary habits–gut microbiome interactions with depression and anxiety.
Green development has gradually become the trend in today’s world. Because of the past development situation, China attaches great importance to green development in recent years. In this chapter, we first present China’s green development model, which is based on the ecological environment and resource carrying capacity constraints, with green economy, resource conservation, environmental friendliness, and social harmony as the main contents, and green innovation is the basic approach to sustainable economic growth. The main objectives are maximization of resource utilization efficiency, optimization of environmental protection, and optimal allocation of social welfare. Then the course of green development in China is historically summarized. Furthermore, this research introduces a series of laws and regulations for promoting green development in the Chinese economic system, resources, and society. In addition, the chapter presents the current status of green development, the current range of issues and challenges it faces, and corresponding suggestions for countermeasures and suggestions proposed based on an evaluation index system under construction. Finally, a future action plan for green development in China is proposed.
This study explored the effects of condition notification based on virtual reality technology on the anxiety levels of parents of children with simple CHD.
Methods:
The subjects of the study were the parents of 60 children with simple CHD who were treated in our centre. The state anxiety scale was used to assess the anxiety status of the parents of the children before and after the condition notification in different ways (based on virtual reality explanations and written explanations).
Results:
In this study, a total of 55 parents of children with CHD successfully completed the survey. At the time of admission, there was no significant difference in the state anxiety scale scores of the parents between the two groups. The anxiety status of the virtual reality group was relieved after the condition notification assisted by virtual reality technology, and there was a significant difference compared with the control group.
Conclusion:
Condition notification based on virtual reality technology can effectively alleviate the anxiety of parents of children with simple CHD, which is worthy of clinical application.
Schizophrenia is a severely debilitating psychiatric disorder with high heritability and polygenic architecture. A higher polygenic risk score for schizophrenia (SzPRS) has been associated with smaller gray matter volume, lower activation, and decreased functional connectivity (FC). However, the effect of polygenic inheritance on the brain white matter microstructure has only been sparsely reported.
Methods
Eighty-four patients with first-episode schizophrenia (FES) patients and ninety-three healthy controls (HC) with genetics, diffusion tensor imaging (DTI), and resting-state functional magnetic resonance imaging (rs-fMRI) data were included in our study. We investigated impaired white matter integrity as measured by fractional anisotropy (FA) in the FES group, further examined the effect of SzPRS on white matter FA and FC in the regions connected by SzPRS-related white matter tracts.
Results
Decreased FA was observed in FES in many commonly identified regions. Among these regions, we observed that in the FES group, but not the HC group, SzPRS was negatively associated with the mean FA in the genu and body of corpus callosum, right anterior corona radiata, and right superior corona radiata. Higher SzPRS was also associated with lower FCs between the left inferior frontal gyrus (IFG)–left inferior temporal gyrus (ITG), right IFG–left ITG, right IFG–left middle frontal gyrus (MFG), and right IFG–right MFG in the FES group.
Conclusion
Higher polygenic risks are linked with disrupted white matter integrity and FC in patients with schizophrenia. These correlations are strongly driven by the interhemispheric callosal fibers and the connections between frontotemporal regions.
The joint effects of stimulus quality and semantic context in visual word recognition were examined with event-related potential (ERP) recordings. In one-character Chinese word recognition, we manipulated stimulus quality at two degradation levels (highly vs. slightly degraded) and semantic context at two priming levels (semantically related vs. unrelated). In a prime–target–probe trial flow, ERPs were recorded to the target character which was presented in either high or slight degradation and which was preceded by either a semantically related or unrelated prime character. The target character was then followed by a probe character which was either identical to or different from the target character. Subjects were instructed to make target–probe matching judgments. The ERP results demonstrated a degradation by priming interaction, with larger N400 semantic priming effects for slightly degraded targets. Moreover, the degradation effects were observed on the P200, N250, and N400. These findings provided evidence for the cascaded model of visual word recognition such that the visual processing cascaded into the semantic stage and thus interacted on the N400 amplitude. The results were compared to an earlier study with a null ERP degradation by priming interaction. The ramifications of these results for models of visual word recognition are discussed.
During the first postnatal week in rodents, cholinergic retinal waves initiate in starburst amacrine cells (SACs), propagating to retinal ganglion cells (RGCs) and visual centers, essential for visual circuit refinement. By modulating exocytosis in SACs, dynamic changes in the protein kinase A (PKA) activity can regulate the spatiotemporal patterns of cholinergic waves. Previously, cysteine string protein-α (CSPα) is found to interact with the core exocytotic machinery by PKA-mediated phosphorylation at serine 10 (S10). However, whether PKA-mediated CSPα phosphorylation may regulate cholinergic waves via SACs remains unknown. Here, we examined how CSPα phosphorylation in SACs regulates cholinergic waves. First, we identified that CSPα1 is the major isoform in developing rat SACs and the inner plexiform layer during the first postnatal week. Using SAC-specific expression, we found that the CSPα1-PKA-phosphodeficient mutant (CSP-S10A) decreased wave frequency, but did not alter the wave spatial correlation compared to control, wild-type CSPα1 (CSP-WT), or two PKA-phosphomimetic mutants (CSP-S10D and CSP-S10E). These suggest that CSPα-S10 phosphodeficiency in SACs dampens the frequency of cholinergic waves. Moreover, the level of phospho-PKA substrates was significantly reduced in SACs overexpressing CSP-S10A compared to control or CSP-WT, suggesting that the dampened wave frequency is correlated with the decreased PKA activity. Further, compared to control or CSP-WT, CSP-S10A in SACs reduced the periodicity of wave-associated postsynaptic currents (PSCs) in neighboring RGCs, suggesting that these RGCs received the weakened synaptic inputs from SACs overexpressing CSP-S10A. Finally, CSP-S10A in SACs decreased the PSC amplitude and the slope to peak PSC compared to control or CSP-WT, suggesting that CSPα-S10 phosphodeficiency may dampen the speed of the SAC-RGC transmission. Thus, via PKA-mediated phosphorylation, CSPα in SACs may facilitate the SAC-RGC transmission, contributing to the robust frequency of cholinergic waves.
Considering the polishing requirements for high-precision aspherical optical mirrors, a hybrid polishing robot composed of a serial–parallel manipulator and a dual rotor grinding system is proposed. Firstly, based on the kinematics of serial components, the equivalent load model for the parallel manipulator is established. Then, the elastodynamic model of kinematic branched-chains of the parallel manipulator is established by using the spatial beam element, and the rigid–flexible coupling dynamic model of the polishing robot is obtained with Kineto-elasto dynamics theory. Further, considering the dynamic properties of the joint clearance, the rigid–flexible coupling dynamic model with the joint clearance for the polishing robot is established. Finally, the equivalent load distribution of the parallel manipulator is analyzed, and the effect of the branched-chain elasticity and joint clearance on the motion error of the polishing robot is studied. This article provides a theoretical basis for improving the motion accuracy and dynamic performance of the hybrid polishing robot.
Informal care provision is an integral part of the long-term care system. However, it has been shown to have negative effects on the carers’ economic activity, and understanding the mechanisms behind this is crucial for social policy design. This study provides new insight into mid-life carers’ decisions to reduce their economic activity through a convergent mixed-methods design. Quantitative analysis of a sample of 2,233 carers aged fifty from the National Child Development Study (NCDS) Wave 8 with follow up at age fifty-five, and qualitative analysis of in-depth interviews of forty-eight carers between 2008-2010, were used. The combined results indicate that being female, single never married, having financial issues, being an employee, and frequently meeting a parent are associated with economic activity reduction; the carers’ own perspectives further elucidate key factors, such as their value and identity, family structure, life course events, and care intensity, which affect their decisions.
Laser–plasma accelerators (LPAs) have great potential to realize a compact X-ray free-electron laser (FEL), which is limited by the beam properties currently. Two-color high-intensity X-ray FEL provides a powerful tool for probing ultrafast dynamic systems. In this paper, we present a simple and feasible method to generate a two-color X-ray FEL pulse based on an LPA beam. In this scheme, time-dependent mismatch along the bunch is generated and manipulated by the designed lattice system, enabling FEL lasing at different wavelength within two undulator sections. The time separation between the two pulses can be precisely adjusted by varying the time-delay chicane. Numerical simulations show that two-color soft X-ray FELs with gigawatt-level peak power and femtosecond duration can be generated, which confirm the validity and feasibility of the scheme.
This study aimed to explore the effects of eye masks on the sleep quality and pain of school-age children with CHD after surgery.
Methods:
Forty school-age children with CHD who underwent open-heart surgery in the Cardiac Surgery Department of a provincial hospital in China from January 2020 to December 2020 were selected. The children were randomly divided into the experimental group (n = 20) and the control group (n = 20). Children in the control group were given routine sleep care, and the children in the experimental group were given a sleep intervention with eye masks for three nights following the removal of tracheal intubation. The Pittsburgh Sleep Quality Index was used to evaluate the sleep quality of the children. The Children’s Pain Behaviour Scale was used to evaluate the pain of the children.
Results:
After three nights of receiving the eye masks intervention, the sleep quality scores of the children in the experimental group were significantly lower than those of the control group, the difference was statistically significant (p < 0.05) and the sleep quality of the children in the experimental group was higher. The pain scores of the children in the experimental group were significantly lower than those of the children in the control group, the difference was statistically significant (p < 0.05), and the children in the experimental group suffered less post-operative pain.
Conclusion:
Eye masks are a simple, safe and economical intervention, that is beneficial for improving the post-operative sleep quality and relieving post-operative pain in school-age children with congenital heart disease.
Frequent freezing injury greatly influences winter wheat production; thus, effective prevention and a command of agricultural production are vital. The freezing injury monitoring method integrated with ‘3S’ (geographic information systems (GIS), global positioning system (GPS) and remote sensing (RS)) technology has an unparalleled advantage. Using HuanJing (HJ)-1A/1B satellite images of a winter wheat field in Shanxi Province, China plus a field survey, crop types and winter wheat planting area were identified through repeated visual interpretations of image information and spatial analyses conducted in GIS. Six vegetation indices were extracted from processed HJ-1A/1B satellite images to determine whether the winter wheat suffered from freezing injury and its degree of severity and recovery, using change vector analysis (CVA), the freeze injury representative vegetation index and the combination of the two methods, respectively. Accuracy of the freezing damage classification results was verified by determining the impact of freezing damage on yield and quantitative analysis. The CVA and the change of normalized difference vegetation index (ΔNDVI) monitoring results were different so a comprehensive analysis of the combination of CVA and ΔNDVI was performed. The area with serious freezing injury covered 0.9% of the total study area, followed by the area of no freezing injury (3.5%), moderate freezing injury (10.2%) and light freezing injury (85.4%). Of the moderate and serious freezing injury areas, 0.2% did not recover; 1.2% of the no freezing injury and light freezing injury areas showed optimal recovery, 15.6% of the light freezing injury and moderate freezing injury areas showed poor recovery, and the remaining areas exhibited general recovery.
Based on hubs of neural circuits associated with addiction and their degree centrality (DC), this study aimed to construct the addiction-related brain networks for patients diagnosed with heroin dependence undertaking stable methadone maintenance treatment (MMT) and further prospectively identify the ones at high risk for relapse with cluster analysis.
Methods
Sixty-two male MMT patients and 30 matched healthy controls (HC) underwent brain resting-state functional MRI data acquisition. The patients received 26-month follow-up for the monthly illegal-drug-use information. Ten addiction-related hubs were chosen to construct a user-defined network for the patients. Then the networks were discriminated with K-means-clustering-algorithm into different groups and followed by comparative analysis to the groups and HC. Regression analysis was used to investigate the brain regions significantly contributed to relapse.
Results
Sixty MMT patients were classified into two groups according to their brain-network patterns calculated by the best clustering-number-K. The two groups had no difference in the demographic, psychological indicators and clinical information except relapse rate and total heroin consumption. The group with high-relapse had a wider range of DC changes in the cortical−striatal−thalamic circuit relative to HC and a reduced DC in the mesocorticolimbic circuit relative to the low-relapse group. DC activity in NAc, vACC, hippocampus and amygdala were closely related with relapse.
Conclusion
MMT patients can be identified and classified into two subgroups with significantly different relapse rates by defining distinct brain-network patterns even if we are blind to their relapse outcomes in advance. This may provide a new strategy to optimize MMT.
Bypass transition in flow over a flat plate triggered by a pair of dielectric-barrier-discharge plasma actuators mounted on the plate surface and aligned in the streamwise direction is investigated. A four-species plasma–fluid model is used to model the electrohydrodynamic force generated by the plasma actuation. A pair of counter-rotating streamwise vortices is created downstream of the actuators, leading to the formation of a high-speed streak in the centre and two low-speed streaks on each side. As the length of actuators increases, more momentum is added to the boundary layer and eventually a turbulent wedge is generated at an almost fixed location. With large spanwise distance between the actuators (wide layout), direct numerical simulations indicate that the low-speed streaks on both sides lose secondary stability via an inclined varicose-like mode simultaneously, leaving a symmetric perturbation pattern with respect to the centre of the actuators. Further downstream, the perturbations are tilted by the mean shear of the high- and low-speed streaks and consequently a ‘W’-shaped pattern is observed. When the pair of plasma actuators is placed closer (narrow layout) in the spanwise direction, the mean shear in the centre becomes stronger and secondary instability first occurs on the high-speed streak with an asymmetric pattern. Inclined varicose-like and sinuous-like instabilities coexist in the following breakdown of the negative streaks on the side and the perturbations remain asymmetric with respect to the centre. Here the tilting of disturbances is dominated by the mean shear in the centre and the perturbations display a ‘V’ shape. Linear analysis techniques, including biglobal stability and transient growth, are performed to further examine the fluid physics; the aforementioned phenomena at narrow and wide layouts, such as the secondary instabilities, the ‘V’ and ‘W’ shapes, and the symmetric and asymmetric breakdown, are all observed.