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Between 838 and 1403 CE, there was a six-century lapse in diplomatic relations between present day China and Japan. This hiatus in what is known as the tribute system has led to an assumption that there was little contact between the two countries in this period. Yiwen Li debunks this assumption, arguing instead that a vibrant Sino-Japanese trade network flourished in this period as Buddhist monks and merchants fostered connections across maritime East Asia. Based on a close examination of sources in multiple languages, including poems and letters, transmitted images and objects, and archaeological discoveries, Li presents a vivid and dynamic picture of the East Asian maritime world. She shows how this Buddhist trade network operated outside of the framework of the tribute system and, through novel interpretations of Buddhist records, provides a new understanding of the relationship between Buddhism and commerce.
Age-of-information (AoI) is used to characterize the freshness of information, and is critical for information monitoring, tracking, and control, which is typically required in many network applications, such as autonomous vehicles, virtual/augmented reality, and Internet-of-Things (IoT). Both inter-arrival times and delays of packets affect AoI performance, and thus traditional delay-efficient algorithms do not necessarily exhibit low AoI performance. This calls for “age-efficient” algorithm design in communication networks, which forms the focus of this chapter. In particular, we first discuss the recent advances in the age-efficient algorithm design for three different types of common network traffic: (i) elastic traffic (cf. Section 1.1): packets are allowed to be delivered without any specific deadline constraints; (ii) inelastic traffic (cf. Section 1.2): packets will be dropped if they are not delivered within a specific deadline; (iii) heterogeneous traffic (cf. Section 1.3): different packets may have different size. To facilitate our discussions, we explicitly consider the discrete-time model and emphasize the difference between age-efficient and delay-efficient algorithm design paradigms. Then, we examine “fresh” scheduling design for remote estimation with the goal of optimally balancing the trade-of between the estimation accuracy and the communication cost (cf. Section 1.4).
This study aimed to explore the mediation effects of one-carbon metabolism (OCM) related nutrients on the association between MTHFR rs1801133 polymorphism and gestational diabetes mellitus (GDM). Folate, vitamin B12 (B12), and homocysteine (Hcy) were measured in the serum of 1254 pregnant women. Linear and logistic regressions were used to estimate the associations of OCM nutrients and MTHFR rs1801133 polymorphism with blood glucose levels and GDM risk. Mediation analysis was applied to test the mediation effects of folate, B12, and Hcy on the association of MTHFR rs1801133 polymorphism with blood glucose concentrations and GDM. Pregnant women with MTHFR rs1801133 CC genotype had higher serum folate (10.75 vs. 8.90 and 9.40 ng/mL) and lower serum Hcy (4.84 vs. 4.93 and 5.20 μmol/L) than those with CT and TT genotypes. Folate concentrations were positively associated with fasting plasma glucose (FPG), 1-h plasma glucose (1-h PG), 2-h plasma glucose (2-h PG), and GDM risk. B12 levels were negatively correlated with FPG and GDM. Although no direct association was found between MTHFR rs1801133 genotypes and GDM, there were significant indirect effects of MTHFR rs1801133 CC genotype on FPG (β: 0.005; 95% CI: 0.001, 0.013), 1-h PG (β: 0.006; 95% CI: 0.001, 0.014), 2-h PG (β: 0.007; 95% CI: 0.001, 0.015), and GDM (β: 0.006; 95% CI: 0.001, 0.014) via folate. In conclusion, serum folate mediates the effect of MTHFR rs1801133 on blood glucose levels and GDM. Our findings potentially provide a feasible GDM prevention strategy via individualized folate supplementation according to the MTHFR genotypes.
Paravulvus zhongshanensis sp. nov., isolated from soil in a location at Jiangsu Province, China, is described and illustrated based on morphological, morphometric and molecular characterizations. The new species is characterized by its body 1.17–1.53 mm long, lip region offset by marked constriction and 12.1–13.8 μm broad, mural tooth deltoid and 9.6–11.7 μm long, neck 278–360 μm long, pharyngeal expansion 164–208 μm long or occupying more than one-half (54–62%) of total neck length, uterus 32.5–35.3 μm long or 1.0–1.1 times the corresponding body diameter, V = 47.8–53.4, paravulvae absent, female tail subcylindrical conoid (30.5–39.5 μm, c = 36.0–45.5, c′ = 1.7–2.2) with widely rounded end, and male unknown. The new species was compared with six known species of the genus including Paravulvus acuticaudatus, Paravulvus confusus, Paravulvus hartingii, Paravulvus iranicus, Paravulvus loofi and Paravulvus microdontus mainly by similarities in having conical tail and c′ value larger than 1.3. The rRNA and mitochondrial cytochrome oxidase subunit 1 genes of the new species were obtained and were used for reconstructing the phylogenetic relationships of the new species.
In order to decrease the influence of system parameters and load on the dynamic performance of permanent magnet synchronous motor (PMSM) in cooperative robot joint modules, a practical model-based robust control method was proposed. It inherits the traditional proportional-integral-derivative (PID) control and robust control based on error and model-based control. We first set up the nominal controller using the dynamics model. In order to limit the influence of uncertainty on dynamic performance, a robust controller is established based on Lyapunov method. The control can be regarded as an improved PID control or a redesigned robust control. Compared with the traditional control method, it is simple to implement and has practical effects. It is proved by theoretical analysis that the controller can guarantee the uniform boundedness and uniform final boundedness of the system. In addition, the prototype of fast controller cSPACE is built on the experiment platform, which averts long-time programming and debugging. It offers immense convenience for practical operation. Finally, numerical simulation and real-time experiment results are presented. Based on cSPACE and a PMSM in the joint module of a practical cooperative robot, the availability of the control design and the achievable control performance are verified.
Attention-deficit/hyperactivity disorder (ADHD) is a clinically heterogeneous neurodevelopmental disorder defined by characteristic behavioral and cognitive features. Abnormal brain dynamic functional connectivity (dFC) has been associated with the disorder. The full spectrum of ADHD-related variation of brain dynamics and its association with behavioral and cognitive features remain to be established.
Methods
We sought to identify patterns of brain dynamics linked to specific behavioral and cognitive dimensions using sparse canonical correlation analysis across a cohort of children with and without ADHD (122 children in total, 63 with ADHD). Then, using mediation analysis, we tested the hypothesis that cognitive deficits mediate the relationship between brain dynamics and ADHD-associated behaviors.
Results
We identified four distinct patterns of dFC, each corresponding to a specific dimension of behavioral or cognitive function (r = 0.811–0.879). Specifically, the inattention/hyperactivity dimension was positively associated with dFC within the default mode network (DMN) and negatively associated with dFC between DMN and the sensorimotor network (SMN); the somatization dimension was positively associated with dFC within DMN and SMN; the inhibition and flexibility dimension and fluency and memory dimensions were both positively associated with dFC within DMN and between DMN and SMN, and negatively associated with dFC between DMN and the fronto-parietal network. Furthermore, we observed that cognitive functions of inhibition and flexibility mediated the relationship between brain dynamics and behavioral manifestations of inattention and hyperactivity.
Conclusions
These findings document the importance of distinct patterns of dynamic functional brain activity for different cardinal behavioral and cognitive features related to ADHD.
We prove that if a solvable group A acts coprimely on a solvable group G, then A has a relatively ‘large’ orbit in its corresponding action on the set of ordinary complex irreducible characters of G. This improves an earlier result of Keller and Yang [‘Orbits of finite solvable groups on characters’, Israel J. Math.199 (2014), 933–940].
Human-centered intelligent human–robot interaction can transcend the traditional keyboard and mouse and have the capacity to understand human communicative intentions by actively mining implicit human clues (e.g., identity information and emotional information) to meet individuals’ needs. Gait is a unique biometric feature that can provide reliable information to recognize emotions even when viewed from a distance. However, the insufficient amount and diversity of training data annotated with emotions severely hinder the application of gait emotion recognition. In this paper, we propose an adversarial learning framework for emotional gait dataset augmentation, with which a two-stage model can be trained to generate a number of synthetic emotional samples by separating identity and emotion representations from gait trajectories. To our knowledge, this is the first work to realize the mutual transformation between natural gait and emotional gait. Experimental results reveal that the synthetic gait samples generated by the proposed networks are rich in emotional information. As a result, the emotion classifier trained on the augmented dataset is competitive with state-of-the-art gait emotion recognition works.
To meet the increasing communication demands, the satellites need to be equipped with the high-accuracy and large-aperture antennas. One of the effective methods to construct the modular antennas with ultra-high accuracy and ultra-large aperture is on-orbit assembly technology. During the on-orbit assembly missions, the assembly error is a key factor to affect the surface accuracy of the modular antennas. This paper studies the node design of each module and the assembly error analysis of the modular antennas. A design method of the module nodes is presented with consideration of the assembly gap between two modules. Meanwhile, a soft connection mechanism is designed to ensure the mobility among the assembly modules. To investigate the transmission law of the assembly errors, an analytical model of assembly error is derived based on the exponential product method. In order to establish the deformation surface with rotation and displacement assembly errors, an error ball concept is proposed by the analytical model. To decrease the assembly errors, the actuators are installed among some modules. Moreover, an adjustment method is proposed to obtain the adjustment amounts of actuators. Finally, the correctness of analytical model and the effectiveness of the adjustment method are demonstrated by the numerical simulations.
Overall diet quality during pregnancy has played an important role on maternal glucose metabolism. However, evidence based on the adherence to the dietary guideline is limited, especially for Asian populations. We aimed to examine the association between adherence to the Chinese dietary guideline measured by the diet balance index for pregnancy (DBI-P) and maternal glucose metabolism, including gestational diabetes mellitus (GDM) status, fasting and 2-hour plasma glucose. Data were obtained from the baseline survey of the Yuexiu birth cohort. We recruited 942 pregnant women at 20-28 weeks of gestation in 2017-2018. Dietary intakes during the past month were collected using a validated semi-quantitative food frequency questionnaire. The scores of DBI-P were calculated to assess dietary quality. Lower absolute values of the scores indicate higher adherence to the Chinese dietary guidelines. All participants underwent a 75g oral glucose tolerance test (OGTT). Multiple linear regression and logistic regression were conducted. The Benjamini-Hochberg (BH) method was used to adjust multiple comparisons across DBI-P food components. The value of high bound score indicator, reflecting excessive total food intake, was positively associated with OGTT-2h glucose levels (β=0.037, P=0.029). After adjustment for multiple comparisons, the score of animal food intake was positively associated with OGTT-2h glucose levels (β=0.045, P=0.045) and risk of GDM (OR=1.105, P=0.030). In conclusion, excessive total food intake was associated with higher postprandial glucose in pregnant women. Lower compliance with the dietary guideline for animal food was associated with both higher postprandial glucose and increased risk of GDM during pregnancy.
Glacial quarrying stems from the fracturing of subglacial bedrock. Much evidence shows that subcritical crack propagation of bedrock is closely related to subglacial water pressure fluctuations. Here we employ a model that assesses the impact of subglacial water pressure fluctuation on cavity length and subcritical crack propagation, while analyzing the effect of a pre-existing crack location using a phase-field model (PFM). Our results indicate that the cavity length is reduced during diurnal fluctuations in water pressure. There are two patterns of subcritical crack propagation on the corner of the step. The first stems from a rapid drop in water pressure. The second occurs after the water pressure recovers from the fluctuation to the initial steady state. This pattern is a consequence of enhanced stress concentration on the step since the modeled cavity length exceeds its steady value and has higher efficiency in promoting subcritical crack propagation. Additionally, based on the PFM results, we speculate that the subcritical crack initiation and propagation happen on a broader scale, including the ice-bed contact region and its adjacent region. Our findings imply that the duration of subcritical crack propagation is short and typically ceases once the cavity length adjusts to reduced water pressure levels.
This study aimed to examine the same-sex matching effect of posttraumatic stress disorder (PTSD) symptoms from parents to children and the mediating role of children’ sense of security and catastrophization. Longitudinal data from 447 parent–child dyads were acquired using self-report scales. Parents (77.0% mothers; Mage = 40.15 years old) reported their PTSD symptoms 3 months after Super Typhoon Lekima, and children (55.9% girls; Mage = 13.40 years old) reported their PTSD symptoms, sense of security, and catastrophization 3 months and 15 months after the typhoon. Results showed that intrusion in mothers predicated intrusion, avoidance, and hyperarousal symptoms in daughters, while avoidance and hyperarousal in mothers predicted the same symptoms in daughters. This was not observed in any other parent–child dyads. Moreover, mothers’ intrusion positively predicted daughters’ PTSD symptoms via daughters’ sense of security and then catastrophization, while mothers’ hyperarousal showed the opposite prediction. These findings suggest that a same-sex matching effect occurs from mothers to daughters in terms of intrusion, avoidance, and hyperarousal symptoms of PTSD. Thus, clinical interventions that target daughters’ PTSD symptoms should also consider mothers’ intrusion and avoidance symptoms. Moreover, it may be possible to develop interventions to improve daughters’ sense of security.
We assessed the efficacy of a culturally competent outreach model with promotoras in raising the coronavirus disease 2019 (COVID-19) first-dose vaccination rates in Chicago’s at-risk ZIP codes from February through May 2021. Utilizing community members from within target communities may reduce barriers, increase vaccination rates, and enhance COVID-19 prevention.
We experimentally investigate the evaporation of very volatile liquid droplets (Novec 7000 Engineered Fluid, chemical name hydrofluoroethers HFE-7000) in a turbulent spray. Droplets with diameters of the order of a few micrometres are produced by a spray nozzle and then injected into a purpose-built enclosed dodecahedral chamber filled with air containing various amounts of water vapour. The ambient temperature and relative humidity in the chamber are carefully controlled. We observe water condensation on the rapidly evaporating droplet, both for the spray and for a single acoustically levitated millimetric Novec 7000 droplet. We further examine the effect of humidity, and reveal that a more humid environment leads to faster evaporation of the volatile liquid, as well as more water condensation. This is explained by the much larger latent heat of water as compared with that of Novec 7000. We extend an analytical model based on Fick's law to quantitatively account for the data.
We show that a complete, two-sided, stable immersed anisotropic minimal hypersurface in
$\mathbf {R}^4$
has intrinsic cubic volume growth, provided the parametric elliptic integral is
$C^2$
-close to the area functional. We also obtain an interior volume upper bound for stable anisotropic minimal hypersurfaces in the unit ball. We can estimate the constants explicitly in all of our results. In particular, this paper gives an alternative proof of our recent stable Bernstein theorem for minimal hypersurfaces in
$\mathbf {R}^4$
. The new proof is more closely related to techniques from the study of strictly positive scalar curvature.
Many studies suggest that both psychotherapy and drug therapy are effective in the treatment of bipolar disorders (BDs). However, the pathophysiology of both types of intervention has not been established definitively.
Methods
An activation likelihood estimation meta-analysis was performed to identify the distinct brain activity alterations between psychotherapy and drug therapy for the treatment of BDs. Articles were identified by searching databases including PubMed, Embase, Cochrane Library, and Web of Science databases. Eligible studies on BDs were published up until 10 June 2021.
Results
21 studies were included and we conducted a meta-analysis for different therapies and imaging tasks. After receiving psychotherapy, BD patients showed increased activation in the inferior frontal gyrus (IFG) and superior temporal gyrus. While after taking drug therapy, BD patients displayed increased activation in the anterior cingulate cortex, medial frontal gyrus, IFG, and decreased activation in the posterior cingulate cortex. The regions of brain activity changes caused by psychotherapy were mostly focused on the frontal areas, while drug therapy mainly impacted on the limbic areas. Different type of tasks also affected brain regions which were activated.
Conclusions
Our comprehensive meta-analysis indicates that these two treatments might have effect on BD in their own therapeutic modes. Psychotherapy might have a top-down effect, while drug therapy might have a bottom-up effect. This study may contribute to differential diagnosis of BDs and would be helpful to finding more accurate neuroimaging biomarkers for BD treatment.
Population control of the house mouse (Mus musculus), Norway rat (Rattus norvegicus) and black rat (Rattus rattus) is common practice worldwide. Our objective was to assess the impact on animal welfare of lethal and non-lethal control methods, including three dispatch methods. We used the Sharp and Saunders welfare assessment model with eight experts scoring eleven control methods and three dispatch methods used on the three species. We presumed the methods were performed as prescribed, only taking into account the effect on the target animal (and not, for example, on non-target catches). We did not assess population control efficacy of the methods. Methods considered to induce the least suffering to the target animal were captive-bolt traps, electrocution traps and cervical dislocation, while those with the greatest impact were anticoagulants, cholecalciferol and deprivation. Experts indicated considerable uncertainty regarding their evaluation of certain methods, which emphasises the need for further scientific research. In particular, the impact of hydrogen cyanide, chloralose and aluminium phosphide on animal welfare ought to be investigated. The experts also stressed the need to improve Standard Operating Procedures and to incorporate animal welfare assessments in Integrated Pest Management (IPM). The results of our study can help laypeople, professionals, regulatory agencies and legislators making well-informed decisions as to which methods to use when controlling commensal rodents.
In this paper, the acoustic resonance mechanism for different axisymmetric screech modes of the underexpanded jets that impinge on an inclined plate is investigated experimentally. The ideally expanded Mach number of jets ($M_j$) ranges from 1.05 to 1.56. The nozzle-to-plate distance at the jet axis and the impingement angle are respectively set as 5.0$D$ and $30^{\circ }$, where $D$ is the nozzle exit diameter. The acoustic results show that the $M_j$ range for the A2 screech mode of impinging jets is broader than that of underexpanded free jets, and a new axisymmetric screech mode A3 appears. With the increase of $M_j$, the effect of the impinging plate on the shock cell structures of jets becomes obvious gradually, and the second suboptimal peaks are evident in the axial wavenumber spectra of mean shock structures. The coherent flow structures at screech frequencies are extracted from time-resolved schlieren images via the spectral proper orthogonal decomposition (SPOD). The axial wavenumber spectra of the selected SPOD modes suggest that the A1, A2 and A3 screech modes are respectively closed by the guided jet modes that are energized by the interactions between the Kelvin–Helmholtz wavepacket and the first three shock wavenumber peaks. The upstream- and downstream-propagating waves that constitute the screech feedback loop are analysed by applying wavenumber filters to the wavenumber spectra of SPOD modes. The frequencies of these three screech modes can be predicted by the phase constraints between the nozzle exit and the rear edge of the third shock cell. For the A3 mode, the inclined plate invades the third shock cell with the increase of $M_j$, and the phase constraint cannot be satisfied at the lower side of the jets, which leads the A3 mode to fade away. The present results suggest that external boundaries can modulate the frequency and mode of jet screech by changing the axial spacings of shock cells.
Direct numerical simulations were performed to characterize fully developed supersonic turbulent channel flows over isothermal rough walls. The effect of roughness was incorporated using a level-set/volume-of-fluid immersed boundary method. Turbulence statistics of five channel flows are compared, including one reference case with both walls smooth and four cases with smooth top walls and bottom walls with two-dimensional (2-D) and three-dimensional (3-D) sinusoidal roughnesses. Results reveal a strong dependence of the turbulence on the roughness topography and the associated shock patterns. Specifically, the 2-D geometries generate strong oblique shock waves that propagate across the channel and are reflected back to the rough-wall side. These strong shocks are absent in the smooth-wall channel and are significantly weaker in cases with 3-D roughness geometries, replaced by weak shocklets. At the impingement locations of the shocks on the top wall in the 2-D roughness cases, localized augmentations of turbulence shear production are observed. Such regions of augmented production also exist for the 3-D cases, at a much weaker level. The oblique shock waves are thought to be responsible for a more significant entropy generation for cases with 2-D surfaces than those with 3-D ones, leading to a higher irreversible heat generation and consequently higher temperature values in 2-D roughness cases. In the present supersonic channels, the effects of roughness extend beyond the near-wall layer due to the shocks. This suggests that outer layer similarity may not fully apply to a rough-wall supersonic turbulent flow.